US3664085A

US3664085A - Packaging machine

Info

Publication number: US3664085A
Application number: US879338A
Authority: US
Inventors: Roy S Rousseau; Raymond J Keating; Gary L Steinke
Original assignee: Kartridg Pak Co
Current assignee: Kartridg Pak Co
Priority date: 1969-11-24
Filing date: 1969-11-24
Publication date: 1972-05-23
Anticipated expiration: 1989-05-23

Abstract

Apparatus and method are disclosed for vacuum packaging of a product in a two element package consisting of a preformed rigid base element and a preformed rigid cover element. The apparatus preferably includes a plurality of platens carried on a conveyor through a number of operating stations where the package is assembled with the base element disposed downwardly. The loosely assembled package is moved into sealing station where a concave housing placed over the package elements forms a vacuum chamber with the platen. The chamber is vacuumized, and an annular sealing member carried within the concavity of the housing moves downwardly to press the peripheral portions of the package elements together while a vacuum is maintained within the chamber.

Description

United States Patent Rousseau et al.

[451 May 23, 1972 Primary ExaminerTravis S. McGehee Attorney-Pendleton, Neuman, Williams & Anderson [57] ABSTRACT Apparatus and method are disclosed for vacuum packaging of a product in a two element package consisting of a preformed rigid base element and a preformed rigid cover element. The apparatus preferably includes a plurality of platens carried on a conveyor through a number of operating stations where the package is assembled with the base element disposed downwardly. The loosely assembled package is moved into sealing station where a concave housing placed over the package elements forms a vacuum chamber with the platen. The chamber is vacuumized, and an annular sealing member carried within the concavity of the housing moves downwardly to press the peripheral portions of the package elements together while a vacuum is maintained within the chamber.

25 Claims, 19 Drawing Figures [54] PACKAGING MACHINE [72] Inventors: Roy S. Rousseau; Raymond J. Keating,

both of Bettendorf; Gary L. Steinke,

Davenport, all of Iowa [73] Assignee: The Kartridge-Pak Co., Davenport, Iowa [22] Filed: Nov. 24, 1969 [21] Appl. No.: 879,338

[52] U.S.Cl ..53/ll2R, 99/171 [51] Int. Cl ..B65b 31/02 [58] FieldofSearch ..53/ll2 R, 112A [56] References Cited UNITED STATES PATENTS 3,283,469 11/1966 McBracly et al ..53/1 12 A X 3,247,643 4/1066 Bartelt ....53/1 12 A 3,340,668 9/1967 Bofinger ..53/1 12 X l I L il llhv l illh-ruu 1 5 I [F i m%\ 8 Sheets-Sheet 1 t Patented I May 23, 1972 Patented May 123, 1972 3,664,085

8 Sheets-Sheet 2 Patented May 23, 1972 8 Sheets-Shout 4 Patented May 23, 1972 s Shets-Sheet 6,015,319 y) 6568 wee 0Q mmw %W\ ew %\W W Gm N0\ \mW\ Patented 'May 23, 1972 '8 Sheets-Sheet '7 Rhw NMN whw RN 3 wNN y Patented May 23,1972 I 3,664,085

8 Sheets-Sheet 8 PACKAGING MACHINE BACKGROUND OF THE INVENTION This invention relates to an apparatus and method for vacuum packaging of a product such as luncheon meat, cheese, frankfurters, or the like within a hermetically sealed, self-supporting container. The method and apparatus are particularly adapted to assemble the two element container or package illustrated and described in Tigner U.S. Pat. No. 3,454,158. This package consists of a preformed, relatively fiat, rigid base element and a preformed inwardly concave rigid cover element. As employed herein the term rigid is intended to mean that the package element maintains'its own shape without internal or external supports and thus is distinguishable from the types of packages wherein one or both of the package elements is merely a thin pliable film. As described herein the package elements or parts are adhesively joined together in the manner described in the Tigner patent, although it will be appreciated that under certain conditions heat sealing equipment could be incorporated into or employed in conjunction with the disclosed apparatus. In the preferred embodiment no thermal forming or heat sealing equipment is needed, since the parts are preformed and the adhesive applied before the parts are handled by the machine.

The method and apparatus of the present invention feature a novel lid or base down assembly technique which permits the product to be aligned on the base and, thus, assures a uniformly neat package. Moreover, by aligning the product on the base prior to the positioning of the cover or shell, the danger of the product coming into contact with the peripheral edge of the shell is greatly minimized thereby assuring a clean surface for contact with the adhesive and providing a strong hermetic seal between the package parts.

SUMMARY OF THE INVENTION The apparatus vacuum packages a product such as sliced luncheon meat in a two element package consisting of a preformed rigid base element and a preformed rigid cover element. In accordance with one embodiment of the invention the apparatus includes a plurality of platens and means, such as conveyor chains, for moving the platens through a plurality of operating stations. Each of the platens has a package element holding means or nest thereon adapted to receive and hold the package elements in substantially aligned superposed relation on a predetermined portion of the platen. There are preferably two or more such holding means on each platen. At the first operating station of the apparatus there is means for placing a base element on each package element holding means, and at the second station there is means for guiding the product into position on the base element.

After the product has been placed on the base element and before the cover element is positioned, it is preferred that there be means at a third station for aligning the product on the base element. This product alignment means is intended to assure that the product, particularly if it is a stacked sliced product such as sliced meat or cheese, will be packaged neatly and that the product will not contact the peripheral or sealing edge of the cover element before that edge engages the adhesive which preferably has been deposited in a peripheral mating groove on the base element.

At the third operating station of the apparatus there is means for placing a cover element over the product and base, and, finally, there is a sealing station wherein a concave housing is moved into sealing engagement with the platen surrounding the package element holding means. The cavity within the housing and the platen define a package-accommodating vacuum chamber, and means is provided for applying a vacuum to this chamber. An annular sealing member, which is carried by the housing within the cavity, is normally held in an upwardly disposed or retracted position. Power means is provided for moving the sealing member downwardly toward the platen while the housing is in sealing engagement with the platen, thereby forcing the peripheral or sealing portions of the package element into sealing engagement while the vacuum is maintained within the chamber.

Means is preferably provided for removing the sealed package from the platen after the platen has been moved from the sealing station. This means may be in the nature of a suction transfer device which transfers the sealed package from one conveyor to another.

The preferred method of the invention includes the steps of placing a relatively flat rigid base element onto an imperforate platen, placing a product in proper alignment on the base element, loosely applying the concave rigid cover element over the product with the peripheral portions of the cover element in close proximity with the peripheral portions of the base element, placing a concave housing over the cover and base elements with the portions thereof surrounding said elements being in sealing engagement with the platen to form with the platen a vacuum chamber surrounding the loosely assembled package elements, drawing a vacuum within the chamber, and while the vacuum is being held, forcing the peripheral portions of the cover element downwardly into sealing engagement with the peripheral portions of the base element and then raising the pressure within the chamber to ambient.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of an apparatus constructed in accordance with this invention, schematically showing the various mechanisms and operating stations of the apparatus;

FIG. 2 is a top plan view of the apparatus illustrated in FIG. 1 showing the platens on which the package elements are assembled and sealed;

FIG. 3 is a exploded view of the package element holding means, the two element package and the product, showing the manner in which these are assembled;

FIG. 4 is a sectional elevational view of a portion of a package assembled by means of the apparatus and method of this invention;

FIG. 5 is a sectional elevational view taken substantially along line 55 of FIG. 1 showing the construction of the platens, the platen guide means and the conveyor;

FIG. 6 is a top plan view of the platen illustrated in FIG. 5;

FIG. 7 is an end elevational view partially in section showing a portion of the mechanism for loading base elements onto the platens at the first station;

FIG. 8 is a side elevational view of the base element loading mechanism, a portion of which has been broken away to show the manner in which the mechanism operates to place a base element onto the package element holding means of each platen;

FIG. 9 is a side elevational view of the product alignment mechanism showing the position of the parts thereof as a platen is being moved into position at this station;

FIG. 10 is an enlarged end elevational view of the product alignment mechanism looking toward the front of the apparatus in the direction opposite the movement of the platens;

FIG. 10A is an enlarged sectional view taken substantially along line l0A-l0A of FIG. 10.

FIG. 1 l is a top plan of the product alignment mechanism;

FIG. 12 is an end elevational view of the product alignment mechanism looking in the same direction as in FIG. 10 and showing the position of the parts as the mechanism engages the product to effect alignment thereof;

FIG. 13 is a sectional view taken substantially along line 13-13 of FIG. 1 and showing the vacuum sealing mechanism;

FIG. 14 is a sectional view taken substantially along line 14-14 of FIG. 13 showing the sealing member carried by the housing within the cavity and the elements carried by the sealing member for engaging and centering the cover element with respect to the base element as the sealing member is moved downwardly toward the platen;

FIG. 15 is a perspective view of the sealing member;

FIG. 16 is a top plan view of the package unloading mechanism which removes the sealed packages from the apparatus;

FIG. 17 is a side elevational view of the package unloading mechanism; and

FIG. 18 is an enlarged sectional view taken substantially along line 18-18 of FIG. 17.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of this invention is particularly adapted to be carried out on the apparatus illustrated in FIGS. 1 and 2 of the drawings. This apparatus operates to vacuum package a product 12 in a two element package 14 of the type disclosed in the Tigner US. Pat. No. 3,454,158 and illustrated in FIGS. 3 and 4 of the drawings herein. The product 12 may, for example, be sliced luncheon meat or sliced cheese, although it will be understood that the package is adapted to hold a number of other products including such food products as, for example, frankfurters and chili.

The package 14 is a two element package consisting of a preformed, relatively flat, rigid, i.e., self-supporting, base element 16 and a preformed, inwardly concave, rigid, i.e., selfsupporting, cover element 18. The base element 16 is preferably formed of a polystyrene foam sheeting with a lamination of barrier film. The base element 16 has a generally flat portion 20 adapted to receive and support the product 12 and a marginal groove 22 adapted to securely receive the cover element 18. An integral extension panel 23 may be provided as a convenient place for printing the date code or the like. An aperture 23a in this panel provides a convenient means for hanging the sealed package for consumer display, and this aperture also facilitates alignment of the base element on the apparatus 10 as will be described herein.

The cover element 18 is preferably formed of a plastic web material by usual pressure-forming techniques, the plastic being of a thickness and of a nature to form a moistureproof and gastight barrier. The cover element 18 may be transparent to allow viewing and inspection of the product 12, and this cover includes a top 24 and a peripheral side wall 26 integral with the top and depending downwardly and outwardly therefrom to engage the marginal groove 22 of the base element 16. It is preferred that a soft tack adhesive be placed in the marginal groove 22 of the base element 16 so that when the bottom edge of the side wall 26 of the cover element comes into contact therewith, the two package elements will be hermetically sealed.

An integral extension flange may be provided, this flange corresponding in size and shape to the extension panel 23 of the base element. This provides a convenient location for a label and a means for grasping of the cover by the consumer when opening the adhesively sealed package. An aperture 25a in this flange aligns with the aperture 23a in the base element when the elements are assembled.

In accordance with this invention the method for packaging the product 12 in the two element package 14 comprises the steps of placing the relatively flat rigid base element 16 onto an imperforate surface such as the platen 28 of the apparatus 10, placing the product onto the base element, aligning the product on the base element, loosely applying the concave cover element 18 over the product 12 so that the peripheral portions are in close proximity with the corresponding peripheral portions of the base element 16, forming with the platen a vacuum chamber surrounding the loosely assembled package elements, drawing a vacuum within the chamber, and while the vacuum condition exists forcing the peripheral portions of the cover element downwardly into sealing engagement with the peripheral portions of the base element. Thereafter, the pressure within the chamber is raised to atmospheric whereby the package will be sealed by a combination of the reduced pressure within the package and the adhesive between the package elements.

As best illustrated in FIGS. 1 and 2 the apparatus 10 of this invention has a frame 30 on which is mounted an endless conveyor 32. The conveyor 32 may, for example, include a pair of spaced, parallel chains 32a and 32b, illustrated in cross section in FIG. 5. The chains are driven by a suitable electric motor 32c and commercially available index drive unit 32a. The motor also drives a cam timer 33. Extending between the chains 32a and 3211 are a plurality of platens 28. At the top portion of the chain run the platens 28 ride upon and are guided by means of horizontal rails 36 and 37 affixed to the frame 30. Each platen carries three rollers 38, two of which engage and roll along the rail 37 and the other roller of which engages and rolls along the rail 36. The three roller contact on the rails 36 and 37 provides a nonrocking movement of the platen along the upper run of the conveyor. Each platen 28 may also be guided in its movement along a rectilinear path by means of a bottom roller 39 which rides within a longitudinal track 40 affixed to the frame 30.

Carried on the top surface of each of the platens 28 are two package-holding

elements

42 and 44. These package-holding elements are identically constructed, each having a base plate 46, the top surface of which is covered with a resilient rubberlike cushion 48 having a raised central portion 480 and a recessed peripheral portion 48b. The cushion 48 is thus shaped to accommodate the bottom of the package base element 16. The recessed peripheral portion of the cushion 48 is adapted to receive the marginal groove 22 of the base element, and the central portion may include recesses 48c in order to accommodate stacking or anti-jamming lugs molded on the bottom side of package base element 16. A longitudinally extending central groove 48d is also preferably provided in the central portion 48a to assure quick separation of the base element 16 from the central portion of the holding element after vacuum sealing.

In order to maintain the base element 16 in proper position on the cushioned package-holding

element

42 or 44, as the case may be, a plurality of upstanding peripheral members or tabs 50 are provided. These tabs are high enough not only to position the base element 16 but also the cover element 18. In the preferred embodiment these tabs are disposed along three sides of the base plate at one end thereof. At the other end of the package-holding element is an upstanding tapered protuberance or spike 52. The spike 52 is adapted to engage in the holes 23a and 25a, respectively, of the base element extension 23 and cover flange 25.

The package-holding

elements

42 and 44 are adapted to hold the package elements in position as the assembly operations are carried out by the apparatus 10. The conveyor 32 indexes the platens 28 through a number of operating stations, the platen remaining in each station a sufficient length of time for the assembly operation at that station to be carried out. In the illustrated embodiment of the apparatus 10 a base element loading mechanism 54 loads the package base elements 16 onto the package-holding

elements

42 and 44 of the platens at the first operating station. At the second station a coding mechanism 56 stamps a suitable code on the base element. At the third station a product guide 58 guides the product into position on the base elements, In the fourth station a product alignment mechanism 60 aligns the product on the base ele ments 16. At the fifth station a cover element loading mechanism 62 places a cover element over the aligned product in such a manner that the package elements are loosely assembled. At the sixth station a sealing mechanism evacuates the package and seals it, and at the seventh and final station an unloading mechanism 66 unloads the assembled package with the product therein from the package-holding elements of the platens, and preferably places this package on a take-off conveyor 68 or the like.

In the drawings the direction of platen movement is indicated by the arrows and is from left to right as viewed in FIGS. 1 and 2. For purposes of description the left-hand end of the apparatus 10 is called the forward or front end of the machine, and the right-hand end is called the rearward or discharge end of the machine. Directions described as upstream and downstream are given with respect to the direction of platen movement.

The structure of the base element loading mechanism 54 is best illustrated in FIGS. 7 and 8 of the drawings. The base element loading mechanism 54 includes a support structure 70 connected to the frame 30 of the apparatus. The support structure includes two upstanding side members 70:: and 70b and a top cross member 700. Connected to and extending upwardly from the cross member 700 of the support structure are two

hoppers

72 and 74 of substantially rectangular cross section adapted to accommodate a stack of package base elements 16 The

hoppers

72 and 74 are open along one side, preferably their downstream side, with the tops of the hoppers being tilted upstream or away from the open side. Thus, a stack of base elements 16 may be inserted easily into each of the hoppers as shown in FIGS. 7 and 8, and there will be no tendency for them to fall through the open side.

Below the hopper 72 at the cross member 700 are mounted a pair of grippers 76 and 78, and a similar pair of grippers 80 and 82 are mounted beneath the hopper 74. The grippers are merely plates having a small inwardly disposed flange 83 along the bottom edge thereof. The

grippers

76 and 80 are fixedly connected to the top cross member 70c of the support structure 70. However, the grippers 78 and 82 are movable. The gripper 78 is movable inwardly toward and away from gripper 76, this movement being effected by means of an air cylinder 84. A second air cylinder 86 (see FIG. 1) is provided for moving the gripper 82 toward and away from the fixed gripper 80 beneath the hopper 74. Pivotally mounted between the upstanding members 700 and 70b of the support structure 70 is a bar 88 at the center of which is affixed an air cylinder 90. At the end of the operating shaft (piston arm) 90a of the cylinder 90 is affixed a crosshead 92 carrying a pair of

resilient suction cups

94 and 96. These

suction cups

94 and 96 are operatively connected to a vacuum source 98 (see FIG. 1) by means of flexible conduits 94a and 96a, respectively.

The bar 88 is rotated by means of a fluid operated rotary actuator 100, which may be an air cylinder, the normal linear reciprocal output motion of the piston of which is converted to rotary motion through a rack and pinion arrangement. Operation of the rotary actuator 100 will thus result in the rotation of the bar 88 and of the apparatus carried thereby including the crosshead 92 and the

suction cups

94 and 96. The

cylinders

84, 86 and 90 and the rotary actuator 100 are operated from a source of fluid pressure such as an air compression unit 102, schematically illustrated in FIG. 1. The timing of the operation of these cylinders and the actuator may be controlled by means of the timing mechanism 33, also schematically illustrated in FIG. 1.

The grippers 76 and 78 below the hopper 72 and the grippers 80 and 82 below the hopper 74 are normally disposed inwardly toward each other just sufficiently to prevent the stack of base elements 16 stored therein from falling through the bottom. When a platen 28 has moved into the first station the timing mechanism 33 actuates the air piston cylinders 84 and 86 to move the movable grippers apart so that the stack of base elements will move downwardly and rest on the

resilient suction cups

94 and 96 carried by the crosshead 92. At this time a vacuum or suction is applied to the cups through the conduits 94a and 96a causing the cups to attach by suction to the lowermost base element in the stack. At this point the air cylinders 84 and 86 are again actuated to move the movable grippers 78 and 82 toward the fixed

grippers

76 and 80, gripping the edges of the package base elements in the two

hoppers

72 and 74.

The air cylinder 90 then is actuated (reversed) to retract the operating arm 90a, drawing the crosshead 92 and the

suction cups

94 and 96 downwardly with the lowermost base elements 16 in the two

stacks

72 and 74 attached thereto. Thus, the lowermost base elements will be stripped from the stack, and the rest of the base elements in the stack will be held in position by means of the grippers. At this point the bar 88 is rotated by means of the rotary actuator 100 moving the two base elements to a position above the package-holding

elements

42 and 44 on the platen in the first station. This position is illustrated by broken lines in FIG. 8. The cylinder 90 is then actuated to extend the operating arm outwardly and position the base elements 16 on the package-holding elements of the platens, and at this time the vacuum in the

cups

94 and 96 is released by suitable valving mechanisms (not shown). In fact, a slight positive pressure may be applied to the conduits 94a and 96a in order to assure separation of the base elements from the suction cups. The cylinder is then reversed to retract the arm 90a and crosshead 92. The rotary actuator is reversed to return the bar 88 and the crosshead 92 to its original position illustrated in FIGS. 7 and 8, and the cylinder 90 is operated to extend the crosshead and cups 94 and 96 upwardly into position for attaching to the next base elements in the

hoppers

72 and 74. The platen 28 with the two base elements 16 being carried thereon is then indexed to the next station.

At the next station there may be a coding mechanism 56, although this is optional with the user of the machine. Frequently it is desirable to stamp on the package a code indicating perhaps the date or other identification of the packaging run. The illustrated coding mechanism shown in FIG. 1 includes two standard endless band stamping devices 104 such as are commonly used in offices for stamping dates. The handle of each stamping device is operatively connected to the operating rod 105 of an air cylinder 106, the air cylinder being mounted on a support 107 attached to the apparatus frame 30. The cylinder 106 and stamping devices 104 may be operated by means of the timing mechanism 33. The platen 28 with the stamped elements 16 carried thereon is then indexed to the next station.

The next station is preferably the product loading station where a product guide 58 is positioned for guiding the product onto the base element 16. If desired, an automatic mechanism may be utilized for placing the stack of meat or other product which is being packaged onto the base element 16 of the package. However, in the illustrated embodiment this is done manually as best illustrated in FIG. 2. Two

auxiliary conveyors

108 and 109 may be employed for this purpose, these auxiliary conveyors being located on opposite sides of the apparatus 10. The platen 28 with the two base elements thereon is indexed to and comes to rest in the loading station in underlying alignment with a product guide 58. The product guide 58 includes two identically constructed sections 580 and 5812. Each guide section may be formed of sheet metal having three integral vertically extending sides including a pair of spaced, parallel,longitudinally extending

sides

110 and 112 and a transverse side 111 which extends between and interconnects the

sides

110 and 112. Each guide section is thus open along its top, bottom and downstream sides. A web 113 connects the side 110 of each guide section to the apparatus frame 30. The spacing between the

sides

110 and 112 of each product guide section is just sufficient to accommodate the product which in this case is a stacked meat product. The operator simply inserts the meat stack into the guide section and onto the underlying base element 16. The two product guide sections 58a and 58b are shown in transverse alignment; however, if desired these may be positioned in longitudinally staggered relation, in which case there would be two consecutive product loading stations, one for one side of the platen 28 and the other station for the other side of the platen. Whether staggered or aligned the sections may be interconnected if desired, although in the illustrated embodiment they are separate.

The product alignment mechanism 60 located at the next operating station of the platen is shown in detail in FIGS. 9 through 12. In the illustrated embodiment the product alignment mechanism 60 includes a mechanism frame 116 comprising a rectangular support structure 118 and two pairs of depending

posts

119 and 120 which are fixed to the apparatus frame 30. The rectangular support structure 118 includes a pair of

transverse members

122 and 124 which are interconnected by means of longitudinal members 126 and 128, the longitudinal members being supported on the post pairs 119 and 120, respectively. Mounted atop the support structure 118 between the

transverse members

122 and 124 is a plate 130 on which is mounted an air cylinder 132. The operating shaft or piston rod 134 of the cylinder 132 extends downwardly through the plate 130, and a subframe 136 is affixed to this shaft, so that the cylinder 132 may be operated in one direction to raise the subframe 136, and in the other direction to lower the subframe.

Attached to and depending from the subframe 136 are two

guide boxes

138 and 140 which support the guide two

product alignment devices

142 and 144 of the product alignment mechanism 60. Two alignment devices are required for the lilustrated embodiment of the invention in view of the fact that two packages are being'assembled on each platen 28 simultaneously. The two

product alignment devices

142 and 144 are identically constructed. Each device includes a first pair of spaced, parallel, vertically disposed, relatively movable product-engaging plates 146 and 148 and a second pair of spaced, vertically disposed, relatively movable product-engaging

plates

150 and 152 which are parallel to each other and are perpendicular to the first pair of plates. Since the illustrated product 12 is a rectangular stack having two pairs of parallel vertical sides, the product-engaging plates in each pair of

plates

146 and 148, and 150 and 152, are also parallel. If the product 12 were round, the plates could be arcuate and perhaps only one pair of plates would be required for alignment. As a practical matter, however, the plates do not have to conform to the shape of the product. All that is necessary is that they conform to the size of the product, and this is a matter of simple adjustment as will be described. Thus the present arrangement of plates will handle both round and rectangular shaped products.

The plate 146 of the first pair of plates is connected to a horizontal bar 154 by means of the vertical arms 155, and the plate 148 is connected to a horizontal bar 156 by the vertical arms 157. The bars 154 and 156 are parallel to each other. In like manner, plate 150 of the second pair of product-engaging plates is connected to a bar 158 by means of vertical arms 160, and the product-engaging plate 152 is connected to the bar 162 by means of the depending arms 163. Each of the

product alignment devices

142 and 144 is operated by a pair of

air cylinders

164 and 166. The air cylinder 164 is connected to the bar 156 from which the product-engaging plate 148 depends, and the air cylinder 166 is connected to the bar 158 from which the product-engaging plate 150 depends.

The interconnection of the bars from which the pairs of product-engaging plates depend is best illustrated in FIG. A. The guide box 138 which is illustrated in FIG. 10A has

side portions

138a, 138b, 1380 and 138d. As previously stated the air cylinder 166 connected to the bar 158 has a piston rod 168 which extends through an aperture 158' in the bar. The piston rod also extends throughan aperture 138a in the side 138a of the guide box, and through an aperture 138C in the opposite wall 138: of the guide box. The end of the operating arm 168 is connected to the bar 162. A pair of guide rods 170 and 172 are also provided. The guide rod 170 is affixed to the bar 162 and extends through and is disposed for sliding movement within apertures in the side walls 1380 and 138a of the guide box and an aperture in the bar 158. In like manner the guide rod 172 affixed to the bar 158 extends through and is disposed for sliding movement within apertures in the side walls 138a and 138a of the guide box and an aperture in the bar 162.

The transverse parallel sides 13812 and 138d of the guide box 138 are similarly apertured for slidingly accommodating the piston rod 174 of the cylinder 164 and the guide rods 176 and 178. The air cylinder 164 is connected to the rod 156, and the piston rod 174 of that cylinder is connected to the rod 154. The guide rods 176 and 178 are respectively connected to the rods 154 and 156.

Each of the operating rods and guide rods carries a stop which may be in the form of a turned shoulder and which is larger in diameter than the apertures in the guide box side walls. Thus the stop 180 is carried on the piston rod 168, the stop 18] is carried on the guide rod 170, and the stop 182 is carried on the guide rod 172. In like manner the stop 184 is carried on the piston rod 174 of the air cylinder 164, the stop 185 is carried on the guide rod 176, and the stop 186 is carried on the guide rod 178. The location of the stops on the rods governs the position of the movable members in their open and closed positions. The stops and 184 on the piston rods of the

air cylinders

166 and 164 govern the position of the

bars

158 and 162 and the bars 156 and 154 in their closed positions illustrated in FIG. 12, where the product-engaging plates are in engagement with the product 12 on the package base plate 16. In similar manner the stops 181 and 182 on the guide rods 170 and 172 and the stops and 186 on the guide rods 176 and 178 will govern the position of the bars and the productengaging plates in the open position illustrated in FIG. 10. While these stops can be made to be adjustable it is preferred that any adjustment be made by means of spacer elements 188 between the product-engaging plates and their vertical arms. The location of the stops is preferably such that when the product-engaging plates are in their open position, they will align with the outer extremity of the marginal groove 22 in the package base element 16, and when these plates are in their closed position they will just slightly compress the product 12.

As previously stated the subframe 136 which carries the two

alignment devices

152 and 144 is moved upwardly and downwardly on the piston rod 134 of the cylinder 132. Affixed to and extending vertically upward from the movable subframe 136 in spaced parallel relationship with the piston rod 134 of the cylinder 132 is a rod 190. The rod 190 extends through an aperture in a plate 192 affixed to the mechanism frame 116 above the subframe 136. The sliding movement of the vertical rod 190 in the aperture of the plate 192 thus serves to guide the vertical movement of the subframe.

Means is preferably provided on the alignment mechanism 60 for pressing the base element 16 flat on the package-

hold ing elements

42 and 44 while the product is being centered or aligned. Afiixed to the subframe 136 are two extension plates 194 and 196. Affixed to and depending from the plate 194 is a bar 198 (see FIG. 9), and at the lower end of this bar is a coil spring 200. The bar 198 and coil spring 200 are vertically aligned with the spike 52 on the package-holding element 44. In like manner a bar 202 is affixed to and depends downwardly from the extension plate 196 and carries a coil spring 204 at its lower end. The bar 202 and coil spring are vertically aligned with the spike 52 on the package-holding element 42. The coil springs 200 and 204 are adapted to be moved over the spikes 52 and to resiliently press the flanges 23 of the base elements 16 flat on the package-holding

elements

42 and 44 when the subframe is moved dovmwardly to its lowered position as illustrated in FIG. 12. This insures proper placement of the two package base elements 16 while the two products are being centered thereon by the mechanism 60.

The dimensions of the parts of the alignment mechanism 60 and length of the stroke of the piston rod 134 are such that when the subframe is in its raised position (as in FIG. 10), the product-engaging plates will be above the level of the product 12 as the package base element 16 and the product are moved into the alignment station on the platen 28, and when the subframe is in its lowered position (as in FIG. 12) the plates will be spaced just above the package base element 16 so that all slices or portions of the product 12 will be engaged during alignment.

In operation, when the platen with the product such as a sliced meat or cheese on the package base element 16 is moved into position beneath the product alignment mechanism 60, this mechanism is actuated by the timer 33 which operates an air control unit 205 (such as a solenoid valve) operatively connected to the pressure tank 98 (see FIG. 1). The air control unit first actuates the cylinder 132 to move the piston rod 134 and the subframe 136 downwardly. As the product-engaging

plates

146, 148, 150 and 152 of each of the

product alignment devices

142 and 144 carried on the subframe 136 approach the platen 28, the

springs

200 and 204 will press the flanges of the base elements 16 over the spikes 52, flattening and assuring proper alignment of the base elements on the package-holding

elements

42 and 44. When the subframe reaches the position illustrated in FIG. 12, the

cylinders

164 and 166 of each of the

product alignment devices

142 and 144 are actuated (also by means of the timer 33 and control unit 205), causing the product-engaging plates to move inwardly toward each other to engage the product on the package base element 16.

It is preferred that the

cylinders

164 and 166 be cycled,

twice, that is, actuated in each direction twice, so that the product-engaging plates will engage the product twice, because it has been found that the best alignment of the product is accomplished in this manner. This is particularly true of a sliced meat or cheese product where it may not only be necessary to align a product on the base element 16, but it may also be necessary to make sure that all of the slices are aligned with one another. After the product-engaging plates have moved inwardly twice, the cylinder 132 is actuated in the opposite direction to raise the subframe and the

product alignment devices

142 and 144. The platen 28 is then indexed by the conveyor mechanism 32 to the next station which is the cover loading station.

The cover element loading mechanism 62, best shown in FIG. 1, is preferably constructed exactly like the base element loading mechanism 54 previously described and illustrated in FIGS. 7 and 8 of the drawings. Since, however, the configuration of the cover element 18 is slightly different from the base element, the stroke of the cylinder 206 will be slightly longer, and the hoppers and gripping elements may be slightly different to accommodate the difference in shape of the cover elements. The operation of the cover element loading mechanism 62 is by the timer 33; however, in addition to the timer it is preferred that photoelectric sensing units 208 be employed to detect the presence of product on the base elements 16 carried by the package-holding

elements

42 and 44 of the platen. Each sensing unit is of standard construction employing a light source and a photocell. If desired, two photoelectric units 208 may be employed for this purpose so that the cover element loading mechanism will only deposit one cover element 18 if there is only one product stack on the platen. Thus the suction lines to the suction cups could be individually controlled by a respective one of the photoelectric units. It also may be desired to employ vacuum switches 210 in the line to the suction cups to sense whether a cover is actually in contact with the vacuum cup. If no cover is transported by the cover element loading mechanism 62, then the vacuum switch would shut off the machine at the end of the cycle, and the platen would not index. In such case a suitable warning such as a bell, buzzer or light could be controlled by the vacuum switch 210. The same type of vacuum switch control may be employed with the base element loading mechanism 54 to signal when either or both of the vacuum cups 94 and 96 are not in contact with a base element 18 when the suction is applied through the lines 940 and 96a.

The cover element loading mechanism 62 is adapted to place a cover element 18 over the stacked and aligned product 12 on the base element 16 with the lower depending edges of the cover element in close proximity with the corresponding peripheral edges of the base element 16 as previously described. The cover element loading mechanism 62 loosely applies the cover so that there is no hermetic seal between the base and cover elements at this stage of the assembly operation.

Following delivery of the cover element by the cover element loading mechanism 62, the conveyor 32 is indexed to the next station which is the sealing station, and in passing from the cover element loading mechanism 62 to the sealing mechanism 64 at the sealing station, the loosely assembled package elements will pass in front of a second set of photoelectric detection units 209. Again, if desired, there may be more than one such unit 209 in order to detect the presence of the package on each of the package-holding

elements

42 and 44 of the platen.

The sealing mechanism 64 is illustrated schematically in FIG. 1 and in more detail in FIG. 13 with parts thereof being shown in FIGS. 14 and 15. This mechanism includes a pair of

vertical posts

211 and 212 fixed in sockets 214 and 216, respectively, the sockets 214 and 216 being welded or otherwise firmly anchored to the apparatus frame 30. Mounted for sliding vertical movement on the

posts

211 and 212 is a bell housing 218. In the illustrated embodiment the bell housing 218 is formed in two parts, a top part 218a and a lower part 21812, the two parts being joined together by means of suitable bolts or the like not shown in the drawings. The lower portion 2l8b of the housing is a rectangular annulus having slightly smaller dimensions than the platen 28. Thus the housing 218 is concave and adapted to fit over the central portion of the platen 28 where the package-holding

elements

42 and 44 are mounted. The lower edge of the lower portion 218b of the bell housing has a resilient seal 220 which when the bell housing is lowered onto the platen 28, will peripherally engage the platen and effect an airtight seal between the platen and the housing. When lowered into the position illustrated in FIG. 13 the bell housing 218 and the platen 28 form a vacuum chamber 222 surrounding the package-holding

elements

42 and 44, and the

package elements

16 and 18, and product 12 which has been placed therebetween.

The bell housing 218 is rigidly connected to a carriage plate 224 by means of suitable structure such as the vertical braces 226. The plate 224, in turn, is connected to the piston or operating rod 228 of a fluid cylinder 230 illustrated in FIG. 1. The fluid cylinder 230, in turn, is affixed to a stationary plate 231 which is attached to the

posts

211 and 212 near the tops thereof. Mounted atop the bell housing 218 between the bell housing and the carriage plate 224 are two

fluid cylinders

232 and 234. The piston rods 232a and 234a of these cylinders extend into the interior of the housing upper portion 218a through the

cylinder end portions

237 and 236, respectively. The seal between the respective

cylinder end portions

236 and 237 and the housing upper portion 218a is such that there is no passage of air therebetween even under conditions of relatively high vacuum within the concavity of the housing 218.

Within the concavity of the housing 218 are two sealing devices 238 and 239. The sealing device 238 is disposed to the left as viewed in FIG. 13 (looking upstream of the conveyor), this device being connected to the piston rod 234a of the cylinder 234. The sealing device 239 is disposed to the right in FIG. 13 and is connected to and operated by the piston rod 232a of the cylinder 232. The sealing device 238 includes a substantially rectangular ring holder 240 having a top portion 240a, a depending skirt portion 240b and a central concavity 240C. The ring holder 240 is operatively connected to the piston rod 234a of the fluid cylinder 234 by means of an attaching rod 242 having a head portion 244 and a shank portion 246. The rod shank portion 246 extends upwardly through the ring holder top 240a, a two-piece spherical selfaligning washer 248, and a tightening nut 249. The upper end of the rod 242 extends into and is locked in a connector 250 by means of a pin 252, the connector, in turn, being afiixed to the output shaft 234a of the hydraulic cylinder 234 by means of a pin 254.

Afi'rxed to the skirt portion 240!) of the ring holder 240 and extending downwardly therefrom is a pressure ring 256. Attached to the inside of the pressure ring 256 are four cover

element centering plates

257, 258, 259, and 260 shown in HG. 14 of the drawings. The pressure ring 256 is illustrated in FIG. 15 of the drawings.

The pressure ring holder 240 carries a roller 262 disposed within the guideway 264 of the I-shaped guide member 266 as shown in FIG. 13. Disposed within the central concavity 2406 of the ring holder 240 is a knockout member 268 which is affixed to the upper portion 218a of the bell housing by suitable fasteners 270 and spacers 272 which extend downwardly from the upper portion of the bell housing 218a into the concavity defined by the rectangular annular lower portion 218b of the bell housing. The knockout 268 which is thus fixed to the housing 218 has a top recess 268a for accommodating the head portion 244 of the ring holder attaching rod 242 which is attached to and reciprocates with the piston rod 234a of the cylinder 234.

On the right-hand side of the bell housing cavity 222 (as viewed in FIG. 13), the sealing device 239 is connected to and carried by the piston rod 232a of the cylinder 232. The corresponding parts have been given prime numbers corresponding to the parts of the sealing device 238 just described. Thus, for the sealing device 238 the ring holder 240 is connected to the output shaft 232a by means of an attaching rod 242 having a head portion 244 and a shank portion 246 which extends through the ring holder top portion 240a, through a two-piece self-aligning washer 248', a tightening nut 249 and into a connector 250'. A pin 252' locks the upper end of the rod 242' within the connector 250', and a pin 254 locks the connector 250 to the piston rod 232a of the cylinder 232. The ring holder 240 has a depending skirt portion 240b which carries a pressure ring 256 and a set of centering plates (only plates 257 and 259' being shown in FIG. 13). A roller 262 attached to the ring holder 240' is disposed within the vertical guideway 264 of the I-shaped guide member 266.

In the upper portion 218a of the housing is a manifold 274 to which a conduit 276 is connected The conduit 276, in turn, is connected to a valve 278 controlled by the timer 33 (see FIG. 1). In one position of actuation the valve 278 connects the conduit to the vacuum tank 102, and in the other position of actuation the valve connects the conduit to the pressure tank 98. If desired, two separate valves may be employed, a vacuum valve for controlling air evacuation from the chamber and an air vent valve for controlling restoration of pressure within the chamber.

From the foregoing it will be apparent that the housing 218 with the sealing devices 238 and 239 carried therewithin is raised and lowered by actuation of the fluid cylinder 230 which raises and lowers the carriage plate 224 rigidly connected to the housing. The sealing devices 238 and 239 within the housing cavity are operated by means of the

cylinders

234 and 232, respectively.

It is preferred that the photoelectric detection units 209, located just upstream from the sealing mechanism 64, be utilized in conjunction with the timer 33 to control the operation of the

cylinders

232 and 234 of the sealing mechanism.

When the housing 218 is first lowered into sealing engagement with the platen 28, both sealing devices 238 and 239 will be in their vacuum or raised positions. The housing is lowered just sufficiently to obtain a face seal between the resilient peripheral seal 220 and the platen 28. When the vacuum is drawn, the platen 28 will actually be raised slightly, increasing the seal at the periphery of the housing and removing the loading on rollers 38. If the unit 209 has detected a package on only one of the package element holding means 42 or 44, only the particular sealing device 238 or 239 as the case may be will be lowered to effect sealing of the package elements.

In the illustrated embodiment there are package elements on the holding means 44, but there is not package on the holding means 42. Consequently, the sealing unit 239 has remained in its raised or vacuum position while the sealing unit 238 has been lowered to its sealing position to effect sealing of the package elements.

As was previously described the package base element 16 has a marginal groove 22, and it is preferred that there be a deposit of pressure-sensitive adhesive in this groove. It is the function of the pressure ring 256 to force the side wall of the I package cover element 18 downwardly into engagement with the inside of the package which is being formed. Thus, the sealing units 238 and 239 are in the raised or vacuum position when the vacuum is first drawn. After the vacuum has been drawn, if the detection means 209 has detected the presence of a package on both of the package element holding means 42 and 44, then both of the sealing devices will be actuated to move the pressure rings 256 and 256 downwardly and force the bottom of the side wall 26 of each of the two cover elements 18 into the marginal groove 22 of their respective base elements 16, thereby effecting a hermetic seal under vacuum conditions.

As the pressure ring 256 is moved downwardly the centering plates 257-260, which will just accommodate the cover element 18, assure that the cover element is precisely aligned with the pressure ring 256 and with the package element holding means 42 and 44. The centering plates are slightly tapered at their leading edge, and should the cover be off-center slightly, the leading edge will engage the cover element 18 and cam it into a precisely centered position, thereby assuring the alignment of the side wall 26 of the cover element with the marginal groove 22 of the base element and assuring proper sealing of the two elements when the pressure ring is in its lowered position. Precise alignment between the package base element 16 and the package cover element 18 is accomplished by a combination of the holding means 42 and 44 (which position the base element 16) and the centering plates 257-260 (which align the cover element 18).

As has been stated, the pressure ring 256 is brought downwardly as a vacuum condition is maintained within the chamber 222. Once the package has been sealed the sealing devices 238 and 239 are returned to their raised position, and the vacuum is released within the chamber 222 to bring the pressure within the chamber at least to ambient. This vacuum release may be accomplished by venting the interior of the chamber to the atmosphere, but in order to speed the operation of the machine it is preferred that this be pressure vented by connecting the conduit 276 to the air pressure tank 98 through the valve 278 or a separate air vent valve. The venting of the chamber to restore ambient pressure may be done immediately after sealing the package elements without waiting for the sealing devices to be raised.

If desired, the system may employ a gas flush by providing for the injection of, for example, an inert gas into the chamber 222 after the vacuum has been drawn and before sealing the package elements. Thus, in effect, the chamber and the package are flushed with the inert gas. This may be desirable for some products including certain food products, and for greatest efficiency a separate gas inlet could be provided in the housing 218.

After the pressure ring has been moved downwardly to effect sealing of the package elements as has been described there may be a tendency in view of the rather tight fit between the centering plates 257-260 and the cover element 18 for the package to retract with the sealing device 238 and be lifted off of the package element holding means 44. However, this is prevented by the knockout device 268 which remains stationary and prevents the package from moving upwardly into the cavity when the pressure ring and sealing plates are raised to their initial retracted position. The knockout 268, in effect, strips the package from the pressure ring and centering plates, and the package thus remains on the package element holding means 44.

When the chamber 222 has been brought at least to ambient and preferably slightly pressurized the housing 218 may be raised by actuation of the cylinder 230. The conveyor with the sealed package or packages thereon is then moved to the final operating station which is the unloading station.

The unloading mechanism 66 is best illustrated in FIGS. 16, 17 and 18. This mechanism includes a horizontal shaft 280 journaled in two

supports

282 and 283 having bases 282a and 283a which are adjustably connected to the frame 30 of the apparatus by means of suitable threaded connectors or bolts 284. One end of the horizontal shaft 280 is connected to a fluid operated rotary actuator 286.

Adjacent the rotary actuator 286 the horizontal shaft 280 carries a first or inner collar 288 fixed to the shaft by means of a set screw 290 (see FIG. 18). The collar carries a pin 202. Surrounding the inner collar 288 is a second or outer collar 294 having a slot 295 therein. The fit between the inner collar 288 and the outer collar 294 is such that free rotation is permitted between these with the pin 292 carried by the inner collar 288 disposed within the slot 295 of the outer collar 294. This, in effect, is a lost motion connection between these two collars. Affixed to the outer collar 294 is an arm 296 which extends upwardly between two

resilient abutments

298 and 299 affixed to the support 283. From this it is apparent that the rotation of the shaft 280 is limited by the length of the slot 295 in the outer collar 294. It will be noted that the slot 295 extends approximately 180 so that the shaft 280 will be permitted to rotate approximately 180. The

resilient abutments

298 and 299 serve as cushions to absorb the shock when the shaft 280 is stopped at the end of the 180 swing.

Mounted on the horizontal shaft 280 are two telescopingly adjustable arms 300 and 302. The end 300a of the arm 300 is locked in its adjustment position by means of a lock nut 300b, and the end 302a of the arm 302 is locked in its position of telescoping adjustment by means of a lock nut 302b. Journaled in the ends 300a and 3020 of the arms 300 and 302 is a bar 304 which carries a pair of

suction cups

306 and 308. The suction cups are connected by means of suction lines 306a and 308a to the vacuum tank 102 illustrated in FIG. 1. Keyed to the end of the bar 304 is a pulley 310, and a similar pulley 312 of the same diameter is affixed to the support 282 as illustrated in FIGS. 16 and 17. Extending around the

pulleys

310 and 312 is a wire 314. As the bar 304 is swung in the counterclockwise direction from the dotted line position to the solid line position, as illustrated in FIG. 17, the pulley 312 will remain stationary while the pulley 310 and the bar 304 will be rotated at the same rate in the clockwise direction. Thus the bar 304 will maintain its orientation with respect to the horizontal, and the

suction cups

306 and 308 will remain vertically disposed. This arrangement assures that the packages 14 will remain horizontally disposed as they are lifted from the platen 28 and swung onto the auxiliary or take-off conveyor 68. The operation of the rotary actuator 286 and of the

suction cups

306 and 308 is preferably controlled by means of suitable valves such as the valve mechanism 278 which in turn is controlled by the timer 33. v

In operation, when the platen is moved to its final station as illustrated in dotted lines in FIG. 17, the

suction cups

306 and 308 are moved downwardly to engage the cover tops 24 of the two packages 14 which have just been assembled and sealed. A suction is then applied through the lines 306a and 308a (see FIG. 6), and the fluid operated rotary actuator 286 is actuated for counterclockwise rotation as viewed in FIG. 17 so that the arm 304 moves in the direction of the arrows in that figure. The arm is swung from the dotted line position to the solid line position as shown in FIG. 17, the package and the suction cups maintaining the same orientation throughout this swinging movement as previously described. When the arm 296 engages the right-hand adjustable abutment 298 the package 14 will be just above the take-off conveyor 68 as illustrated in FIG. 17. At this point the suction is released either by valving the lines 306a and 308a to the atmosphere or connecting them to the pressure tank 98 through a valve such as valve 278, thereby releasing the package onto the take-ofi conveyor 68. The apparatus is thus adapted to package a product quickly, easily and efficiently in a preformed two element package.

It is to be understood that the present disclosure has been made only by way of example and that many modifications and changes in various details may be readily apparent to those skilled in the art. For example, the operation of the various cooperating mechanisms is preferably accomplished by air cylinders as has been described. It would, however, be entirely within the scope of the invention if the power were supplied hydraulically or in some instances even electrically by means of solenoids. Additional changes in the structural details and arrangement of parts may be resorted to without departing from the invention.

What is claimed is:

1. An apparatus for vacuum packaging of a product in a two element package consisting of a preformed rigid base element and a preformed rigid cover element, said apparatus comprising at least one platen, means on said platen for holding the package elements in substantially aligned superposed relation on a predetermined portion of said platen, said holding means including a plurality of upstanding members spaced to engage peripheral portions of the package elements to restrict the lateral movement of the package elements with respect to said platen, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said holding means, whereby said housing concavity and said platen define a package-accommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing member carried by said housing within said concavity, said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.

2. The apparatus of claim 1 wherein said holding means further includes a protuberance positioned to extend through a correspondingly positioned aperture in at least one of the package elements.

3. The apparatus of claim 1 wherein said holding means further includes a plate affixed to said platen, and a resilient cushion on said plate.

4. The apparatus of claim 3 wherein said cushion has a raised central portion and recessed peripheral portions for accommodating the peripheral portions of said package elements when they are forced downwardly by said sealing member.

5. The apparatus of claim 1 wherein there are a plurality of platens, and means is provided for moving said platens sequentially into and through a plurality of operating stations including a sealing station in which each platen is positioned for sealing engagement with said housing.

6. The apparatus of claim 1 and further including means for supplying gas to the vacuum chamber at greater than atmospheric pressure after the peripheral portion of the package elements have been forced into sealing engagement by said sealing member.

7. The apparatus of claim 1 wherein said sealing member carries a plurality of tapered inwardly disposed elements for engaging and centering the cover element with respect to the base element as said sealing member is moved downwardly toward said platen.

8. The apparatus of claim 1 and further including means disposed interiorly of said sealing member and connected to said housing for dislodging the package elements from said sealing member when said sealing member is returned to its retracted position.

9. The apparatus of claim 5 wherein horizontal guide means is provided for maintaining said platens in a substantially horizontal orientation as they are moved into and through said operating stations, and vertical guide means is provided for guiding said platens along a substantially straight path.

10. The apparatus of claim 1 wherein on each platen there are a plurality of means for holding the package elements, whereby a plurality of packages may be assembled and sealed on each platen simultaneously.

11. An apparatus for vacuum packaging of a product in a two element package consisting of a preformed relatively flat rigid base element and a preformed inwardly concave rigid cover element, one of said package elements carrying an adhesive whereby when the package elements are pressed together an hermetic seal will be formed therebetween; said apparatus comprising a plurality of platens, means adapted to move said platens sequentially along a predetermined path through a plurality of operating stations, each of said platens having package element holding means thereon adapted to receive and hold the package elements in substantially aligned superposed relation on a predetermined portion of the platen, first package element placement means for placing a base element on said package element holding means at a first station, means for guiding the product into position on the base element at a second station, second package element placement means for placing a cover element over the product and base at a third station, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said package element holding means at a fourth station, whereby said housing cavity and said platen define a packageaccommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing member carried by said housing within said concavity, said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.

12. The apparatus of claim 1 l and further including product alignment means intermediate said product guiding means and said cover placing means for aligning the product on the base element.

13. The apparatus of claim 11 wherein at least one of said package element placement means includes means above said conveyor at the associated station for holding a stack of package elements, an arm mounted for movement relative to said frame and carrying package element attachment means for engaging and releasably attaching to the lowermost package element in the stack, means for moving said arm first to effect removal of the attached package element from the stack and then to effect movement of the package element onto said package element holding means.

14. The apparatus of claim 13 wherein said arm is pivotally mounted on said frame and is movable first radially inwardly to effect removal of the attached package element, then is pivotally moved to a position above said holding means and then is moved radially outward to place the package element in said holding means.

15. The apparatus of claim 13 wherein said means carried by said arm for engaging and releasably attaching to the lowermost package element in the stack is a resilient cup, and means is provided for drawing a vacuum within said cup when said cup is in engagement with the lowermost package element in the stack and for releasing the vacuum when that package element has been moved onto said package element holding means.

16. The apparatus of claim 12 wherein said product alignment means includes a subframe, at least two product engaging members mounted on said subframe for limited movement toward and away from each other, and means for moving said subframe from a raised position above said package element holding means to a lowered position within said package element holding means whereby when said members are moved toward each other they will engage and align the product on the base element within said holding means.

17. The apparatus of claim 12 wherein there are two package element holding means on each platen, and said product alignment means includes a subframe, at least two sets of product alignment plates carried by said subframe, each set comprising two pairs of plates, the plates in each pair being substantially parallel and relatively movable with respect to one another, the pairs of plates in each set being disposed substantially perpendicular with respect to one another, means for moving said subframe from a raised position above said package element holding means to a lowered position, and means for moving the plates in each set toward each other to substantially simultaneously engage and align the products on the base elements within said two package element holding means.

18. The apparatus of claim 17 wherein said product alignment means includes two pairs of product engaging members, said pairs being mounted on said subframe for transverse movement with respect to each other, whereby the product may be aligned on four sides.

19. The apparatus of claim 11 and further including means for removing the sealed package from said platen after said platen has moved from the sealing station.

20. The apparatus of claim 19 wherein said means for removing the sealed package from said platen includes at least one suction cup, means for moving said suction cup between two locations, and means for applying a suction to said suction cup in one location and releasing it in the other location, whereby said suction cup may attach to the package in said one location and the package may be transported to and released in said other location.

21. The apparatus of claim 19 wherein said means for removing the sealed package from said platen includes a support, an arm mounted on said support for pivotalmovement about a horizontal axis, package attachment means mounted on said arm for rotational movement about a horizontal axis, and means for rotating said package attachment means relative to said arm at substantially the same angular rate and in the opposite direction as the pivotal movement of said arm with respect to said support, whereby said package attachment means will maintain substantially the same orientation with respect to the horizontal throughout the pivotal movement of said arm.

22. The apparatus of claim 20 wherein said means for rotating said package attachment means relative to said arm includes a first pulley afiixed to said support, a second pulley affixed to said package attachment means, and an endless band encircling said pulleys.

23. An apparatus for vacuum packaging of a product in a package consisting of two rigid package elements, said apparatus comprising a plurality of platens, means for moving said platens sequentially along a predetermined path through a plurality of operating stations, each of said platens having package element holding means thereon adapted to receive and hold the package elements in substantially aligned superposed relation on a predetermined portion of the platen, means for holding a supply stack of each of said preformed package elements and for sequentially transferring said elements from the supply stacks to said platens at predetermined operating stations, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said package element holding means after said package elements have been positioned thereon, whereby said housing cavity and said platen define a package-accommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing member carried by said housing within said concavity said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.

24. An apparatus for vacuum packaging of a product in a two element package consisting of a preformed relatively flat rigid base element and a preformed inwardly concave rigid cover element; said apparatus comprising a plurality of platens, means adapted to move said platens sequentially along a predetermined path through a plurality of operating stations, each of said platens having package element holding means thereon adapted to receive and hold the package elements in substantially aligned superposed relation on a predetermined portion of the platen, first package element placement means for placing one of said elements on said package element holding means at a first station, means for guiding the product into position with respect to said one element at a second station, second package element placement means for placing the other of said elements over the product and said one element at a third station, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said package element holding means at a fourth station, whereby said housing cavity and said platen define a package-accommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing member carried by said housing within said concavity, said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.

25. An apparatus for vacuum packaging of the product in a two element package consisting of a preformed rigid base element and a preformed rigid cover element, said apparatus comprising at least one platen, a plurality of means on said platen for holding the package elements in substantially aligned superposed relation on a predetermined portion of said platen, whereby a plurality of packages may be assembled and sealed on each platen simultaneously, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said holding means, whereby said housing concavity and said platen define a package-accommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing member carried by said housing within said concavity, said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.

Claims

11. An apparatus for vacuum packaging of a product in a two element package consisting of a preformed relatively flat rigid base element and a preformed inwardly concave rigid cover element, one of said package elements carrying an adhesive whereby when the package elements are pressed together an hermetic seal will be formed therebetween; said apparatus comprising a plurality of platens, means adapted to move said platens sequentially along a predetermined path through a plurality of operating stations, each of said platens having package element holding means thereon adapted to receive and hold the package elements in substantially aligned superposed relation on a predetermined portion of the platen, first package element placement means for placing a base element on said package element holding means at a first station, means for guiding the product into position on the base element at a second station, second package element placement means for placing a cover element over the product and base at a third station, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said package element holding means at a fourth station, whereby said housing cavity and said platen define a package-accommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing member carried by said housing within said concavity, said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.

12. The apparatus of claim 11 and further including product alignment means intermediate said product guiding means and said cover placing means for aligning the product on the base element.

21. The apparatus of claim 19 wherein said means for removing the sealed package from said platen includes a support, an arm mounted on said support for pivotal movement about a horizontal axis, package attachment means mounted on said arm for rotational movement about a horizontal axis, and means for rotating said package attachment means relative to said arm at substantially the same angular rate and in the opposite direction as the pivotal movement of said arm with respect to said support, whereby said package attachment means will maintain substantially the same orientation with respect to the horizontal throughout the pivotal movement of said arm.

22. The apparatus of claim 20 wherein said means for rotating said package attachment means relative to said arm includes a first pulley affixed to said support, a second pulley affixed to said package attachment means, and an endless band encircling said pulleys.

23. An apparatus for vacuum packaging of a product in a package consisting of two rigid package elements, said apparatus comprising a plurality of platens, means for moving said platens sequentially along a predetermined path through a plurality of operating stations, each of said platens having package element holding means thereon adapted to receive and hold the package elements in substantially aligned superposed relation on a predetermined portion of the platen, means for holding a supply stack of each of said preformed package elements and for sequentially transferring said elements from the supply stacks to said platens at predetermined operating stations, a concave housing, means for moving said housing into sealing engagement with said platen surrounding said package element holding means after said package elements have been positioned thereon, whereby said housing cavity and said platen define a package-accommodating vacuum chamber, means for applying a vacuum to said vacuum chamber, an annular sealing mEmber carried by said housing within said concavity, said sealing member being normally held in an upwardly disposed retracted position, and power means for moving said sealing member downwardly toward said platen while said housing is in sealing engagement with said platen, whereby the peripheral portions of said package elements may be forced into sealing engagement while a vacuum is being applied to said chamber.