US3668941A

US3668941A - Retrieval apparatus for die casting equipment

Info

Publication number: US3668941A
Application number: US51528A
Authority: US
Inventors: Herman M Canner
Original assignee: Sterling Detroit Co
Current assignee: Sterling Detroit Co
Priority date: 1970-07-01
Filing date: 1970-07-01
Publication date: 1972-06-13
Anticipated expiration: 1989-06-13

Abstract

A retrieval apparatus for die casting equipment which includes an extension tube for reaching into a die casting machine carrying an extension bar for increasing the range of the reach, there being pick-up jaws on the extension bar for clamping an ejected casting and returning it to a drop position over a quench tank, the jaws being movable to change the position of the casting so that it will orient properly with the quench tank and thus reduce the spacing required for the assembly. A mechanism for actuating the jaws from a release position to a pick-up position and again back to a release position together with a locking means for the jaws is incorporated to operate automatically during the extension and retraction motion of the slide tube and slide bar, and safety release mounting means are provided for the assembly to avoid damage due to possible malfunction.

Description

United States Patent Canner I 1 June 13, 1972 [54] RETRIEVAL APPARATUS FOR DIE 3,586,176 6/1971 Rackman et al ..2l4/l B CASTING EQUIPMENT Primary Examiner-William F. ODea [72] Inventor: Herman M. Canner, Detroit, Mich. Assismm Examine, wes|ey R tliff Jr. [73] Assignee: Sterling Detroit Company, Detroit, Mich. A"0mey Bames' Ra'sch Choate [22] Filed: July 1, 1970 [57] ABSTRACT [21] Appl.No.: 51,528 A retrieval apparatus for die casting equipment which includes an extension tube for reaching into a die casting 52 us. (:1. ....74/s9.17, 214/1 BB, 214/1 CM machine carrying i increasing [51] Int Cl F16]! 27/02 the reach, there being pick-up aws on the extension bar for 58 Field of Search .....21 1/1 B, 1 13B, 1 ET, 1 CM; clamping ejected and rimming a dmp over a quench tank, the aws being movable to change the 74/89.l7

position of the casting so that It will orient properly with the quench tank and thus reduce the spacing required for the as- [56] References Cited sembly. A mechanism for actuating the jaws from a release UNITED STATES PATENTS position to a pick-up position and again back to a release position together with a locking means for the jaws is incorporated Chambers t at a tomati ally during the extension and retraction 3,033,059 5/ 1962 Melton et -214/1CM motion of the slide tube and slide bar, and safety release 3,107,402 10/1963 Hunter ..2l4/l BB mounting means are provided f the assembly to avoid 3,262,593 7/1966 Hamer... ..214/1 CM damage due to possiue lf i 3,303,941 2/1967 Hanes ..2l4/1 B 3,482,71 1 12/1969 Bohme et a1 ..2l4/1 CM 5 Claims, 16 Drawing Figures .PATENTEnJumi'sin 3.668841 sum 10F 9 FIG. 1

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SHEET 9 OF 9 INVENTOR MFR/MAN m. ("ANA/[R ATTO R N EYS This invention relates toRetrieval Apparatus for Die Casting Equipment and more particularly to an apparatus for retrieving completed castings which are ejected from the molds of an automatic die casting machine.

The apparatus eliminates the necessity for an operator reaching in to retrieve the casting from the mold as it is ejected and thus prevents the hazards that are incident to an operator extending his hands andarms into the area where moving parts might cause injury.

In order to simulate the actions of an operator and also provide safety vehicles which prevent damage to the machine, that is, either the retrieval apparatus for the casting machine, it is necessary to have certain safety controls and a construc tion which prevents damage in the event of a maladjustment or accidental'cycling.

In a casting machine, the die consists of two parts which close during thecasting and which open after the casting has cooled sufficiently that it may be ejected by standard ejection equipment. In order that the cycle may continue as rapidly as possible, it is necessary that the retrieval apparatus synchronize with the motion of the dies to the extent that it may follow this motion and, in a sense, pick up the casting as the dies are opening and remove it rapidly so that the-dies may move into the next cycle without undue interruption.

It is, therefore, an object of the present invention to provide a machine which will perform this function and move synchronously with the die opening action, pick up the casting and move it out of the die area with proper acceleration and deceleration motion which will prevent damage to the casting or the possibility of accidental dislodgment.

Other objects and features of the invention include a double projection arm with harmonic motion which provides power acceleration-deceleration characteristics, a swivel jaw which can change the part position as it returns to a dump-quench position, anautomatic lock which insures proper jaw position during pick up and a lock-release actuated duringretraction, and a mechanism for relating the arm,.jaws, and lock for interaction in proper sequence. j

Other objects and features of the invention will be apparent in thefollowing description and claims in which the principles of the invention are disclosed together with the manner of use in connection with the best mode presently contemplated for the invention.

Drawings accompany the disclosure and the various views thereof may be briefly described as:

FIG. I, perspective view of the overall machine showing the relationship of the parts.

FIG. 2, a sectional view on line 2-2 of FIG. 1.

FIG. 3, a view on line 3-3 of FIG. 2.

FIG. 4, a sectional view on line 44 of FIG. 3.

FIG. 5, a segmental view of the machine showing a drive mechanism for the fore and aft thrust arm.

FIG. 6, a top view of the drive taken on line 6-6 of FIG. 5.

FIG. 7, an enlarged view of the gripping jaw and the actuating mechanism.

FIG. 8, a sectional view on line 8-8 of FIG. 7.

FIG. 9, a sectional view on line 9-9 of FIG. 8.

FIG. 10, a view on the outer end of the arm projection mechanism taken on line 10-10 of FIG. 7.

FIG. 11, a view of a portion of the mechanism of FIG. 10 showing certain parts in elevation.

FIG. 12, a sectional view on line 12-12 ofFIG. 11.

FIG. 13, a sectional view on line 13-13 of FIG. 10.

FIG. 14, a view similar to FIG. 13 showing the parts in a different relationship.

FIG. 15, a detail of a control mechanism within the extension arm.

FIG. 16, a detail of the jaw control of the mechanism.

REF ERRING TO THE DRAWINGS:

A machine base has suitable railmounts 22 to permit the retrieval apparatus to be mounted adjacent a molding machine. Generally, there is a quench tank between the base 20 and the molding or casting machine so that the part may be removed from the molds, pulled away from the machine, and then dropped into a quench tank where it can be conveyed to the next manufacturing operation.

A suitable control control box 24 is provided for controls which can be electrical and hydraulic and follow standard conventional practice. Two

parallel mount bars

26 and 28, see FIG. 2, are mounted on the base 20 and transversely of these bars are

cross bars

30 and 32 suitably anchored to the mount bars and connected by

cylindrical guide rods

34 and 36 forming horizontal ways. On these rods are

cylindrical slides

38 and 40, each of which carries, respectively, an upright 42 and 44 connected by a cross mount plate 46.

This plate serves as an anchor for an adjustable piston rod 48 extending from a piston cylinder assembly 50 mounted on the cross plate 32. On'the top of the upright 42 is a swivel block 52 suitably pivoted for swinging on a vertical axis, there being a rigid relatively large bearing post anchored in upright 42 for carrying the swivel block 52, FIG. 3. On a cantilever bar 54 are mounted suitable solenoid valves 56 and other controls which can be utilized for actuating the machine.

The vertically disposed swivel plate 60 is rigidly mounted on the swivel block -52, this plate serving as an arm mount to carry the retrieval arm and the mechanism for the pick-up of a molded part. This plate 60 is associated with the other upright 44 in a manner illustrated especially in FIGS. 3, 4 and 5.

The top of the pillar 44 has a ride plate 62 which supports the bottom edge of plate 60, this edge being apertured at 64 to receive an eye-bolt 66 held in place by a bolt 68. The eye-bolt passes through a housing 70 and is affixed by a threaded connection to an arm 72 around which is mounted a compression spring 74. At the end of the arm 72 is a spring retainer 76,

- FIG. 2, held in place by nuts 78. Thus, it will be seen that plate 60 is pivotally mounted on the the upright 42 by the swivel block 52 held in place on post 53 by a disc and the plate 60 is also supported on the ride plate 62 but may move on this plate by reason of the pivot post 53 on which the swivel block is mounted so that the entire plate may shift around the pivot axis restrained by the spring 74. The purpose of this swivel mount is to allow some motion of the entire mount for the retrieval arm in the event of a malfunction or improper timing in the retrieval action.

Looking now at the top of the plate 60 there is found the mount for a large rectangular tube 90, this being held in place by two

rectangulan brackets

92 and 94 having depending extensions 96 and 98 which are suitably welded or bolted to the plate 60. These rectangular brackets or

blocks

92 and 94 are designed to carry suitable roller mounts for the slide tube 100 as shown in the sectional view in FIG. 8.

A double roller 102 at the bottom of FIG. 8 on a common axis shaft 104 is mounted in a journal block 106 to carry the bottom load of the tube 100. Similarly on the left hand side, a double roller 108'on a shaft 110 is mounted in a suitable bearing journal 112.

At the top of the mount is a double bearing roller 114 on a shaft 1 16 mounted in ajournal block 120. In this instance, the journal block is movable in a cavity 126 and its position is adjustable by a screw 128 which can be locked by a nut 130. The opening in the journal block for the shaft 116 is substantially larger than the shaft and is filled with a plurality of closely positioned rings 132 nestled adjacent each other across the shaft. The same construction is shown at the right-hand side of the mount in FIG. 8 where rollers 134 are mounted on a shaft 136 in a journal 138 which again carries the eye rings 140. On this side of the device, a screw 142 can adjust the block 138 and be locked by a nut 144. Thus, the journal block and the journal block 138 can be urged against the side walls of the tube 100 by a resilient pressure due to the resilience of the 0- rings which mount the bearing shafts.

It is very difficult without a great deal of expense to provide a projection tube which has a constant dimension throughout its length and which has perfectly straight lines on the side walls. The mount described in connection with FIG. 8 allows the tube 100 to pass through the bearings with a smooth, clean movement and the O-ring mount of the bearing shaft takes up the variation in the dimensions as the tube moves. This provides a very inexpensive compensating bearing mount which avoids the necessity for any springs in the unit. In the mounting block 92 a similar bearing arrangement is provided.

The actuation of the slide tube 100 is achieved through a double arm drive as illustrated in FIGS. 1 and 5. The tube has a depending stud 150 on which is pivotally mount an eye ring 152 which is adjustably connected with the end of a long arm 154 of a double arm drive. This arm extends to the left as viewed in FIG. and connects through an adjustable pivot block 156 to a short arm 158. This short arm is socketed in a pivot drive block 160 carried by a shaft 162 extending form a gear rack housing 164 in which is mounted a gear 166 on shaft 162, and a rack 168, the latter being driven by a piston rod 170 of a piston cylinder assembly 172, FIG. 6.

Thus, actuation of the piston in the cylinder 172 can cause retraction of the slide 100 to one position as shown in FIG. 5 and an extension of the slide tube by the dimension equal to twice the distance between the center of the shaft 162 and the center of the pivot block 156, this being adjustable. It will also be evident that this motion in both the forward and return action will be harmonic in the sense that it will start with a low acceleration and gradually increase in its acceleration and then after the arm 158 passes the 90 mark in its travel, it will decelerate to the end of the travel. Thus, a smooth movement of the slide tube 100 can be obtained by a suitable direction of pressure to one end or the other of the pressure cylinder combination 172. The motion will be declerating at the part pickup position and also at the part drop position.

A shown in FIG. 6, the housing 164 is mounted on plate 60 by a back wall 174 of the casting, this being bolted on at 176.

- On either side of the block 160 are stop blocks 178 which can contact plate 160 to limit the motion of the arm 158. If desired, these blocks may be capped with a resilient material to absorb shock.

The motion which is afforded by the swing of the arm 158 is not sufficicnt to reach over a quench trough and into the casting machine. Accordingly, there is mounted in the slide tube 100 a further extensible unit to complete the necessary extension. The timing of this extension can either be simultaneous or sequential.

The secondary extension arm comprises a solid shaft 180 of square cross section, actuated by a rod 182, extending from a piston cylinder assembly 184 at the rear end of the slide tube 100 (see FIG. 7). If the view of FIG. 1 is considered the front of the machine, the view of FIG. 7 is from the rear or opposite side. The stroke of the slide bar or shaft 180, therefore, is dependent on the length of the cylinder 184. The slide bar is suitably mounted and guided in the slide tube 100.

At the forward end of the extension bar 180, as viewed in FIG. 7, is a mount bar 186 for a jaw mechanism shown in detail in FIG. 16. This mechanism has a jaw 188 which cooperates with a second jaw 190, these being moved around mounting pivot pins 192 and 194 by

toggle links

196 and 198 actuated by a piston-cylinder combination 200 and an associated push-pull block 202. The entire jaw assembly is mounted on a pivot block 204 carried on a shaft 206 mounted in

bearings

208 and 210 in a housing 212 carried on the mount bar 186.

Slidable in the housing 212 is a slide rack 214 which cooperates with a rack gear 216 affixed to the shaft 206. Thus, the jaw assembly can be rotated on a vertical axis from the position shown in FIG. 16 to a position which is 90 away. When a casting is quite long, it is withdrawn when the jaws grab the central sprue and comes away from the casting machine in plane transverse to the general axis. If a quench tank is positioned between the casting machine and the retrieval apparatus, it would have to be quite wide to receive the casting cross-wise of the tank. The pivoting of the jaws moves the casting so that it can be dropped into the machine lengthwise making it possible to use a narrower quench tank and this saving floor space.

As shown in FIG. 10, the rack 214 has a stop dowel 218 fastened thereto and extending therefrom the outer end being controlled at the limits of movement by the ends of a groove 220 in a stop-plate 222. Thus, the rotating shaft 206 is limited to a rotation. Accordingly, when the jaws 188-190 have grasped the sprue plug 22 (FIGS. 7 and 16) and removed a casting, as viewed for example in FIG. 1, the jaws can be rotated 90 so the casting will be positioned in a plane transverse of the direction of movement of the arm 180 so that it may be dropped into a quenching trough or tank in the proper orientation.

The actuation of the jaws for closing and opening by the piston-cylinder assembly 200 can be controlled by suitable limit switches and solenoid-actuated valves as are commonly used in the industry.

The rotation of the jaws is accomplished at suitable times during the extension and retraction stroke of the extension bar 180 and there is provided suitable locking mechanisms to stabilize the jaws in the pick-up position during the out movement. An actuator rod 230 which parallels the bar 180, is fixed at the fore end to the rack block 214, FIGS. 10, 11 and at the aft end to a block 232 which rides on the trailing end of the bar 180, FIGS. 8, 15. A bracket 234 within the tube surrounds the bar as illustrated in FIG. 8, and this bracket carries a plunger 236 backed by a spring 238. The travel of the plunger is limited by a cross-pin 240 and a notch 242. The length of the rod 230 relative to the stroke of the extension bar is such that the heel block 232 of the rod 230 will be against the plunger compressing the spring when the bar is fully extended. This will retract the rack bar 214 and move the jaws to the grab" position, the rack in the retraced position being shown in FIG. 11.

A latch 250 for the rack which locks the swivel head is shown in FIGS. 10 to 14. This latch 250 slides up and down in block 212. In the down" position, it locks the rack 214 in the grab position of the jaws. See FIG. 13. In the up" position, FIG. 14, the rack can move to pivot the jaws to a release" position. The latch block is actuated to an up position by a stationary finger 252, FIG. 7, which has a beveled end 254 to cooperate with an overhang projection 256 on the latch block, FIGS. 12,13,14.

The finger 252 is mounted on a bracket 258 carried by the forward end of the extension tube 100. It will be noted that as the block 212 retracts, the tapered end 254 of the finger 252 will enter below the overhang 256 and lift the entire latch block. In FIG. 13, the latch block is shown in the lock position wherein a projection 260 on the latch block enters a notch 262 in the rack 214 to prevent the rack from shifting. In FIG. 14, t latch 250 is shown in the lifted position wherein the projection 260 is lifted out of the opening in the gear rack slide 214.

Thus, to review the general operation of the jaws and projection bar 180, when the arm 180 is projected outwardly from the tube 100, the finger 252 will slide out from under the latch 250. This will allow the latch to drop so that the projection 260 can ride on the top of the rack 214. As the arm 180 moves outwardly, the heel block 232 is stopped by the plunger 236 and the continued motion of the arm 180 will draw back the gear rack bar 214 to the position shown in FIG. 11. In this position, the latch 250 can drop to the locking position shown in FIG. 13. Thus, the jaws will be locked in the position shown in FIG. 7 and will move out to grab the sprue 224. Then upon the return of the jaws to the position shown in FIG. 7, the nose 254 will have entered under the projection 256 to lift the locking block or latch so that further retraction of the extension bar 180 will cause an abutment of the rear end of the gear rack against the forward end of the extension tube 100 moving the gear rack into the position shown in FIG. 10.

This movement willswing the jaws 188-190 to a position 90 away from that shown in FIG. 7. After this motion of the jaws, the jaws can be released by contact, for example, of a roller 270 on a bracket 272 with an arm 274 of a limit switch 276 causing an actuation of a proper valve for the appropriate movement of the jaw-actuating piston-cylinder 200 to the release position. While all of the piping for the cylinders has not been shown, there are two

pipes

280 and 282 which are mounted on a vertical bracket 284 on the forward end of the extension tube 100 to carry a control fluid to the pistoncylinder combination 200 (see FIG. 7).

Thus, in full sequence, the carriage plate 160 as viewed in FIG. 1 can move, by actuation of piston-cylinder motor 50, on the carriage rods 34-36 in a manner to synchronize with the motion of the casting machine and also to effect the proper withdrawal of the completed casting from the machine. When,

the carriage plate 160 is in the proper position, the arm 100 will be projected forward in the harmonic motion provided by the

arms

154 and 158, this resulting from the action of the rack 168 and the piston-cylinder assembly 172. As the projection tube 100 moves to its outermost position, the pistoncylinder assembly 184 (FIG. 7) will come into play to move the projection bar 180 outwardly; as it reaches the end of its stroke, the heel block 232 will stop at the plunger 236 pulling the gear rack 214 rearwardly to swivel the jaws 188-190 to the proper pick-up position.

When this position is reached, the latch 250 will drop into the position illustrated in FIG. 13 and lock the jaws. The jaws can then pick up the casting from the casting machine and withdraw it to a drop position. When the tube 100 and bar 180 retract, this causes the finger 252 to enter the latch underneath the projection 256 and lift the latch to the unlocked position. At this time, further retraction of the bar 180 will cause the gear rack 214 to impact inwardly to swing the jaws to the release position which would be 90 away from the position of the jaw as viewed in FIG. 1. Thus, the carriage, the extension tube 100 and the extension bar 180, as well as the jaws, are all synchronized to'cooperate with a casting machine which is placed beside the assembly.

WHAT IS CLAIMED AS NEW IS:

1. A casting retrieval machine for use with automatic die casting machines of the type having horizontally separable dies which comprises:

a. a base,

b. horizontal ways on said base,

0. spaced slides supported on said ways,

d. cross mount means supported on and spanning said slides,

e. means to move said cross mount on said slides,

i. an arm mount on said cross mount means,

g. a slide tube slidably mounted in said arm mount,

h. means on said cross-mount means for moving said slide tube in a projection stroke transversely of said spaced slides in a harmonic motion with the lowest acceleration and deceleration at the ends of the stroke,

i. a slide bar slidably mounted in the end of said slide tube movable to project out of said tube in the same direction as the projection stroke of the tube, and

j. means carried by said tube to project said slide bar in a projection stroke beyond the end of said slide tube.

2. A casting retrieval machine as defined in claim 1 in which means is interposed between said cross mount and said arm mount to pivotally mount said arm mount on a vertical pivot post for movement in a horizontal plane and resilient means is disposed to resist said movement.

3. A casting retrieval machine as defined in claim 1 in which a vertical pivot post means is provided adjacent one of said slides to pivotally mount said arm mount means on said cross mount means, and means is provided adjacent the other of said slides to support said arm mount means in a swinging arc motion.

4. A casting retrieval machine as defined in claim 3 in which means is provided to resiliently bias said am mount against said swing arc motion.

5. A casting retrieval machine as defined 1n claim 1 in which slide bearings are provided in said arm mount for said slide tube comprising a bearing housing and two pairs of opposed rollers mounted in said housing to contact the outer walls of said tube, at least one roller of each pair being mounted on an axle, and a plurality of resilient O-rings surrounding said axle and lodged in a recess in said housing to provide a resilient mount for said axles and allow compensatory movement of said rollers as said tube slides in said arm mount.

Claims

1. A casting retrieval machine for use with automatic die casting machines of the type having horizontally separable dies which comprises: a. a base, b. horizontal ways on said base, c. spaced slides supported on said ways, d. cross mount means supported on and spanning said slides, e. means to move said cross mount on said slides, f. an arm mount on said cross mount means, g. a slide tube slidably mounted in said arm mount, h. means on said cross-mount means for moving said slide tube in a projection stroke transversely of said spaced slides in a harmonic motion with the lowest acceleration and deceleration at the ends of the stroke, i. a slide bar slidably mounted in the end of said slide tube movable to project out of said tube in the same direction as the projection stroke of the tube, and j. means carried by said tube to project said slide bar in a projection stroke beyond the end of said slide tube.

4. A casting retrieval machine as defined in claim 3 in which means is provided to resiliently bias said arm mount against said swing arc motion.

5. A casting retrieval machine as defined in claim 1 in which slide bearings are provided in said arm mount for said slide tube comprising a bearing housing and two pairs of opposed rollers mounted in said housing to contact the outer walls of said tube, at least one roller of each pair being mounted on an axle, and a plurality of resilient O-rings surrounding said axle and lodged in a recess in said housing to provide a resilient mount for said axles and allow compensatory movement of said rollers as said tube slides in said arm mount.