US20100170318A1

US20100170318A1 - Elbow formation apparatus

Info

Publication number: US20100170318A1
Application number: US12/683,552
Authority: US
Inventors: Matthew Lawler
Original assignee: Formtek Inc
Current assignee: Formtek Inc
Priority date: 2009-01-08
Filing date: 2010-01-07
Publication date: 2010-07-08

Abstract

An apparatus for forming and rotating interconnected sections of a cylindrical sheet metal workpiece to provide an elbow. The apparatus includes a frame, a head rotatably arranged within the frame and a tool ring mounted to the frame, the head and tool ring being co-operable for sectioning and joining segments of the workpiece. The apparatus also includes a drive drum mounted within the frame for gripping and rotating the segments, and a control module for selectively activating the head, the ring, and the drive drum to form an elbow.

Description

CROSS-REFERENCE OF RELATED APPLICATION

WO This application claims the benefit of U.S. Provisional Application Ser. No. 61/143253, filed on Jan. 8, 2009, and herein incorporated by reference in its entirety.

FIELD OF THE INVENTION

This invention relates, in general, to a formation and rotation apparatus for use in forming and rotating interconnected sections of a cylindrical workpiece, and deals more particular with a formation and rotation apparatus that will automatically form and turn each section of cylindrical workpiece to its proper orientation even in the cases of large diameter elbow workpieces.

BACKGROUND OF THE INVENTION

Elbow sections of ductwork are typically formed as straight pieces of cylindrical ductwork prior to being manipulated into a finished elbow having a substantial bend attributed thereto. This manipulation has traditionally been accomplished by hand.
While the known hand manipulation of elbow workpieces is effective to a certain degree, such a process is manually difficult and time consuming, as well as oftentimes resulting in the formation of finished elbows having slightly non-uniform characteristics.
Additional complications arise when large diameter elbow workpieces are utilized.
With the forgoing problems and concerns in mind, it is the general object of the present invention to provide a dual head elbow rotator apparatus that will automatically form and rotate large diameter sections of an elbow workpiece to form the finished elbow.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an elbow rotator that will automatically turn each section of an elbow duct to their proper orientations.
It is another object of the present invention to provide an elbow rotator that will automatically turn each section of an elbow duct to their proper orientations while being incorporated into an elbow formation apparatus.
It is another object of the present invention to provide an elbow rotator that will automatically turn each section of an elbow duct to their proper orientations while serving as a stand-alone apparatus.
It is another object of the present invention to provide an elbow rotator that will simultaneously rotate each integrally formed section of an elbow workpiece.
It is another object of the present invention to provide a dual head elbow rotator apparatus.
It is another object of the present invention to provide a dual head elbow rotator apparatus, which can balance the forces incident upon the elbow workpieces during formation.
It is therefore an important aspect of the present invention to propose a formation and rotation apparatus for use in forming and rotating interconnected sections of a cylindrical sheet metal workpiece, including a frame, a head rotatably arranged within the frame, the head carrying at least one cutting wheel and at least one beading wheel, a tool ring mounted to the frame and carrying rollers operable with the wheels for sectioning and joining segments of the workpiece, a drive drum mounted within the frame for gripping and rotating the segments, and a control module for selectively activating the head, the ring, and the drive drum to form an elbow.
These and other objectives of the present invention, and their preferred embodiments, shall become clear by consideration of the specification, claims and drawings taken as a whole.
Another alternative embodiment relates, in general, to an elbow rotator apparatus, and deals more particularly with an elbow rotator apparatus which is capable of handling workpieces of varying diameters, sectioning these workpieces, and rotating them into finished elbow units, or the like.
Elbow sections of ductwork are typically formed as straight pieces of cylindrical ductwork prior to being manipulated into a finished elbow having a substantial bend attributed thereto. This manipulation has traditionally been accomplished by hand.
While the known hand manipulation of elbow workpieces is effective to a certain degree, such a process is manually difficult and time consuming, as well as oftentimes resulting in the formation of finished elbows having slightly non-uniform characteristics.
Automated systems have also been proposed to accomplish the rotation of the individual elbow sections of a workpiece; however, these proposed systems cannot perform their operation over a wide range of elbow workpieces that may vary in diameter.
With the forgoing problems and concerns in mind, it is the general object of the present invention to provide an elbow rotator that will automatically form and rotate individual sections of an elbow workpiece, regardless of the diameter of the elbow workpiece, or the difference in diameter between subsequent processes.
It is an object of the present invention to provide an elbow rotator that will automatically form and turn each section of an elbow duct to their proper orientations.
It is another object of the present invention to provide an elbow rotator that will automatically turn each section of an elbow duct to their proper orientations while being incorporated into an elbow formation apparatus.
It is another object of the present invention to provide an elbow rotator that will automatically turn each section of an elbow duct to their proper orientations while serving as a stand alone apparatus.
It is another object of the present invention to provide an elbow rotator that is capable of accommodating elbow workpieces of varying diameters.
These and other objectives of the present invention, and their preferred embodiments, shall become clear by consideration of the specification, claims and drawings taken as a whole.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a straight elbow section of ductwork, or elbow workpiece, having a plurality of integrally formed sections.

FIG. 2 illustrates a finished elbow section of ductwork.

FIG. 3 is partial cross-sectional view of an elbow machine having an elbow rotator, wherein the elbow workpiece is in a first position, according to one embodiment of the present invention.

FIG. 4 is partial cross-sectional view of an elbow machine having an elbow rotator, wherein the elbow workpiece is in a second position, according to one embodiment of the present invention.

FIG. 5 is partial cross-sectional view of an elbow machine having an elbow rotator, wherein the elbow workpiece is in a finished position, according to one embodiment of the present invention.

FIG. 6 is partial cross-sectional view of an elbow machine having an elbow rotator, wherein the elbow rotator is tilted back to permit removal of the finished elbow unit, according to one embodiment of the present invention.

FIG. 7 is a front, partial cross-sectional view of the elbow rotator of the present invention.

FIG. 8 is a top, partial cross-sectional view of the elbow rotator of the present invention.

FIG. 9 is a side, partial cross-sectional view of the elbow rotator of the present invention.

FIG. 10 is partial cross-sectional side view of a freestanding elbow rotator, according to another embodiment of the present invention.

FIG. 11 is a partial cross-sectional end view of a gripping arm of the freestanding elbow rotator in its ‘up’ position.

FIG. 12 is a partial cross-sectional top view of the gripping arms of the free standing elbow rotator in their ‘down’ position and secured about their respective sections of the elbow workpiece.

FIG. 13 is a partial cross-sectional side view of the gripping arms of the free standing elbow rotator after rotation back to their ‘up’ position, thereby forming a completed elbow.

FIG. 14 is a partial cross-sectional end view of a gripping arm of the freestanding elbow rotator.

FIG. 15 illustrate the gripping arm of FIG. 14 as it accommodates elbow workpieces of differing diameters.

FIG. 16 is a partial cross-sectional end view of the gripping arms of the free standing elbow rotator in both its ‘up’ and ‘down’ positions.

FIG. 17 illustrates a dual-slide block cutting and beading apparatus, in accordance with another embodiment of the present invention.

FIG. 18 illustrates a side view of a dual slide-block head utilized in the dual-slide block cutting and beading apparatus of FIG. 17, in accordance with one embodiment of the present invention.

FIG. 19 illustrates a partial cross-sectional top view of a dual slide-block head shown in FIG. 18.

FIGS. 20-23 illustrate various perspective views of a fully-assembled top-loading elbow cutter and rotator according to a further embodiment of the present invention.

FIGS. 24-27 illustrate various casing-removed perspective views of the elbow cutter and rotator shown in FIGS. 20-23.

FIG. 28 illustrates an assembled view of a tool ring subassembly of the elbow cutter and rotator shown in FIGS. 20-27.

FIG. 29 illustrates an exploded assembly view of an improved bead/lock shoe or slide block head for use in the elbow cutter and rotator shown in FIGS. 20-27.

FIG. 30 illustrates an exploded assembly view of a drum drive subassembly of the elbow cutter and rotator shown in FIGS. 20-27.

FIG. 31 illustrates a perspective view of an arbor head and arbor column of the elbow cutter and rotator shown in FIGS. 20-27.

FIG. 32 illustrates an exploded assembly view of an arbor head of the elbow cutter and rotator shown in FIGS. 20-27.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates a section of an elbow ductwork 10 prior to the elbow 10 being rotated into its final form. As can be seen in FIG. 1, the elbow 10 includes several sections 12 that have been formed by bending a sheet-metal workpiece, or the like, into a cylindrical shape about a common seam 14. Each of the sections 12 are separated from one another by an elbow joint 16 which has been cut and formed in the elbow 10 in a manner well known in the art. As will be appreciated, each of the section 12 of the elbow 10 shown in FIG. 1 must be turned with respect to one another in order to form the finished elbow 18, shown in FIG. 2.
As illustrated in FIG. 2, and in contrast to the elbow workpiece shown in FIG. 1, the seam 14 is no longer continuous along the length of the finished elbow 18 due to the individual rotation of the sections 12. During rotation, it is typical that each of the sections 12 experience an approximately 180° rotation with respect to adjacent sections in order to provide the ‘bend’, typically approximately 90°, to the finished elbow (as shown in FIG. 2). The present invention provides a heretofore-unknown apparatus having the ability to automate the rotation of the individual sections 12 of an elbow workpiece.
It should be noted that while a rotation of approximately 180° has been described, other angles of rotation may also be accomplished without departing from the broader aspects of the present invention.
FIG. 3 illustrates an elbow machine 20 equipped with an elbow rotator 22 of the present invention. As shown in FIG. 3, an elbow workpiece 24 is mounted within the elbow machine 20 after the elbow workpiece 24 has been formed by the elbow machine 20 in accordance with a known process. A first section 26 of the elbow workpiece 24 is then rotated by the elbow rotator 22, as shown in FIG. 3, in a manner to be explained shortly. FIGS. 4 and 5 illustrate the subsequent rotation, and corresponding re-orientation, of additional sections of the elbow workpiece 24 by the elbow rotator 22. FIG. 6 illustrates the finished elbow workpiece 24 and, in phantom, a new elbow workpiece 28 being mounted for similar processing.
The elbow rotator 22 is preferably mounted on an inclined work surface 30 of the elbow machine 20 so as to accept and automatically manipulate each section of the elbow workpiece 24 as each joint of the elbow workpiece 24 is formed by the elbow machine 20. FIG. 7 is a front, partial cross sectional view of the elbow rotator 22. As shown in FIG. 7, the elbow rotator 22 includes a pair of gripping arms 32 having flexible, resilient pads 34 disposed on the ends thereof. A hydraulic cylinder 36, or the like, is utilized to close the gripping arms 32 about a lead section of the elbow workpiece 24. As will be appreciated, the gripping arms 32 will grip the elbow workpiece 24 with a force commensurate with the hydraulic pressure applied to the cylinder 36. Moreover, the cylinder 36 is disposed between the gripping arms 32 and does not control the position of the gripping arms 32, which will center themselves about and on the elbow workpiece 24 as the elbow workpiece is being rotated. As is also shown in FIG. 7, a frame 38 is rotatably mounted on the inclined work surface 30 about pivot joints 40 and substantially supports elbow rotator 22.
It will be readily appreciated that while hydraulic cylinders have been discussed in connection with the present invention, other alternative designs, such as but not limited to pneumatic systems, may be utilized without departing from the broader aspects of the present invention.
FIG. 8 illustrates a top, partial cross-sectional view of the elbow rotator 22. As seen in FIG. 8, the gripping arms 32 are mounted to a gripping frame 42, which selectively pivots about an axis A that is substantially perpendicular to the plane of the joint and is centered on the axis of the joint. The gripping frame 42 is rotated by a roller chain 44 driven by a rotary actuator 46. The rotary actuator 46 will selectively cause the frame 42 and gripping arms 32 to rotate approximately 180°. A sprocket 48 is located on the rotary actuator 46 includes more teeth than a similar sprocket 50 located on the frame 42 in order to provide rotation of more than 180°, should such a rotation be desired. Stroke limiters are utilized on the rotary actuator 46 to adjust the amount of rotation that is produced. Moreover, an adjustable torque limiter 52 is utilized in conjunction with the rotary actuator 46 to limit the available torque that will rotate the elbow workpiece 24.
In operation, each section 12 of the elbow workpiece 24 is sequentially gripped by the gripping arms 32 and rotated approximately 180° under the direction of the rotary actuator 46. After each section 12 of the elbow workpiece 24 has been rotated, the rotary actuator 46 is returned to its home position. The gripper frame 42 rotates back by only the amount over 180° that a given section 12 of the elbow workpiece 24 may have been rotated. In such instances, the gripper frame 42 is stopped by a ratchet and pawl wheel assembly 54 (seen in FIG. 9) at the 180° position, while torque limiter 52 slips to allow the rotary actuator 46 to continue rotating to its home position. In this manner, each successive section 12 of the elbow workpiece 24 may be rotated in the same direction and, moreover, the direction of rotation may be easily reversed by changing the configuration of the ratchet and pawl assembly 54 and reversing the home position of the rotary actuator 46. In this regard, there is a preferred direction to rotate the sections 12 of the elbow workpiece 24 depending on which direction the seam 14 is lapped so that the seam 14 will not catch. In order to achieve proper positioning, it may also be necessary to rotate the first section 12 of the elbow workpiece 24 more than 180°, as the first section 12 of the elbow workpiece 24 may have been slightly rotated during formation of the joints 16.
FIG. 9 illustrates a side, partial cross-sectional view of the elbow rotator 22. As seen in FIG. 9, the elbow rotator 22 includes a hydraulic positioning cylinder 56, which selectively causes the elbow rotator 22 to pivot about pivot joints 40. Indeed, as best seen with reference to FIGS. 9 and 6, the frame 38 along with the gripping arms 32 and rotary actuator 46 may be selectively tipped back at the conclusion of each elbow production cycle (the position illustrated in FIG. 6) so as to provide enough clearance to remove the finished elbow from the elbow machine 20 and insert the new elbow workpiece 28. The frame 38 would then be tilted back to its operative position to ready for the next elbow production cycle.
It will be readily appreciated that the elbow rotator 22 of the present invention may automatically and sequentially rotate differing sections of a formed elbow workpiece to their proper orientation without the need for manual manipulation of the same. The production of finished elbow units may therefore be substantially increased as compared to manual production methods currently in use. Moreover, given that the elbow rotator 22 resets to a known ‘home position’ prior to each rotation, and further, that the elbow rotator 22 may even compensate for the slight rotation of the first section of the elbow workpiece, the present invention is capable of repetitively producing finished elbow units having substantially uniform characteristics and mechanical tolerances.
While FIGS. 3-9 illustrate the elbow rotator 22 being integrated with the elbow formation machine 20, the present invention is not limited in this regard. Indeed, the present invention contemplates a free standing elbow rotator apparatus that is not integrated with another device or apparatus, rather it may be a wholly separate unit for accomplishing the same general task as the elbow rotator 22, discussed above.
FIG. 10 illustrates a partial cross-sectional side view of a freestanding elbow rotator 60, in accordance with another embodiment of the present invention. As shown in FIG. 10, the freestanding elbow rotator includes a housing 62 and an inclined work surface 64 contained therein.
As discussed previously, adjustable elbow workpieces are initially manufactured as straight tubes having a series of integrated sections. After an elbow machine has finished making the joints in an elbow workpiece 24, it is still in a straight shape (as seen in FIG. 1). The elbow workpiece must then be rotated into its angled configuration and joined together with other elbows to form a “donut”. This donut arrangement is the preferred method of shipping elbows for many manufacturers.
A 90-degree elbow 24 consists of four sections 12, such as shown in FIG. 2. As mentioned previously, each section 12 must be rotated approximately 180 degrees relative to the adjacent sections 12 to position the elbow in its 90-degree shape. There are other elbow configurations that have fewer sections and may result in different angles of the rotated elbow, but all typically require the 180 degree rotation of the adjacent sections in order to produce a finished, or completed, elbow configuration.
Returning to FIG. 10, the freestanding elbow rotator 60 further includes a pair of gripping arms 66 and 68. Each of the gripping arms supports several pairs of gripping fingers 70 and is oriented for selective rotation about rotational axis R. In operation, the gripping fingers of the gripping arms will selectively secure about each section 12 of the elbow workpiece and rotate them to their finished orientation, as will be described in more detail hereinafter. While the free standing elbow rotator has been described as having several pairs of gripping fingers for each of the gripping arms, the present invention is not limited in this regard as the gripping arms may alternatively support any number of pairs of gripping fingers, inclusive of a single pair, without departing from the broader aspects of the present invention.
It is therefore an important aspect of the present invention that one pair of the gripping fingers 70 will rotate each of the sections 12 so that all of the sections 12 can be turned at the same time. In this manner, the freestanding elbow rotator 60 of the present invention serves to significantly reduce the manufacturing time of elbow workpieces, especially as contrasted with the previously known manual rotation of the sections of the elbow workpiece 24.
As further shown in FIG. 10, and with the gripping arms 66 and 68 in their ‘up’ position, an operator will load a straight elbow workpiece 72 into the free standing elbow rotator 60, from the front and substantially in a direction L. The straight elbow workpiece is preferably loaded so as to ensure that the seam 14 is up and the crimped end out.
Once a start button is pushed, the straight elbow workpiece 72 is swung up to re-position the straight elbow workpiece at a second, inclined position 74 within the free standing elbow rotator 60. Thus, the longitudinal axis of the straight elbow workpiece will be arranged substantially parallel with, and preferably concentrically aligned with, the rotational axis R of the gripping arms 66 and 68. FIG. 11 is a partial cross-sectional view of the straight elbow workpiece as it is arranged within the free standing elbow rotator with the gripping arms, and gripping fingers 70, in their ‘up’ position.
A cam and roller arrangement permits each of the gripping arms 66 and 68 to pivot as they rotate down. As each of the gripping arms reach their ‘down’ position, each of the gripping fingers 70 will contact an adjustable stop 76 to arrest each of the gripping fingers in the proper starting position to grip the sections 12. The stops are manually adjustable to produce the correct amount of rotation to each of the sections.
With the gripping arms 66 and 68 in their ‘down’ position, the gripping arms 70 are caused to close about each section 12 of the elbow workpiece 74. As shown in FIG. 12, the gripping fingers contacting adjacent sections are alternately connected to gripping arms 66 and 68. That is, on a four-section elbow workpiece, the first and third section gripping fingers are mounted on one gripping arm, and the second and fourth section gripping fingers are mounted on the other gripping arm. FIG. 12 illustrates the free standing elbow rotator 60 when the gripping arms are in their ‘down’ position, and the gripping fingers are each secured about their respective sections of the elbow workpiece.
After gripping each of the sections 12, one gripping arm 66 or 68 rotates ninety (90) degrees clockwise while the other gripping arm 68 or 66 rotates approximately ninety (90) degrees counterclockwise. As the arms rotate, they swing out approximately fifteen (15) degrees to follow the arching movement caused by rotating the angled joints 16 of the elbow workpiece 74. Each set of the gripping fingers 70 is mounted to the gripping arms by a pivoted joint so the gripping fingers may twist with each section of the elbow workpiece as it is rotated. The rotations of the two gripping arms are synchronized by a chain and sprocket assembly operatively connected to two shafts 78 that are geared together, as shown in FIG. 12. The rotation of the gripping arms thereby causes the individual sections of the elbow workpiece to rotate to their final position and thus define a completed elbow 60. FIG. 13 illustrates a side, partial cross-sectional view of the completed elbow workpiece 80 once the gripping arms 66 and 68 have completed their upwards rotation.
Once the gripping arms 66 and 68 have been fully rotated to occupy once again their ‘up’ position, as shown in FIG. 13, the gripping fingers 70 release the completed elbow 80. The completed elbow is then pivoted, in opposition to the direction in which it was initially loaded, for subsequent removal from the housing 62 of the freestanding elbow rotator 60.
FIG. 14 illustrates an end view of one set of the gripping fingers 70 attached to one of the gripping arms 66 or 68. As shown in FIG. 14, the distal ends of the gripping fingers are each equipped with a resilient and elastic cushioning bumper 82, such as but not limited to a urethane bumper or the like, for protecting the body of the elbow workpiece 74 during operation of the free standing elbow rotator 60. A pneumatic cylinder 84, or the like, is utilized to selective cause the gripping fingers to alternatively expand and constrict about the body of the elbow workpiece.
Moreover, as shown in FIG. 15, the gripping fingers 70 of the gripping arms 66 and 68 may be selectively configured to match elbow workpieces 72/74 of differing diameters. That is, by changing the attachment points 86 of the gripping fingers to the gripping arms, as well as by changing the attachment points 88 of the gripping fingers to the cylinder 84 itself, it is thus possible to accurately accommodate elbow workpieces of differing diameters. As discussed hereinafter, at least one of the gripping arms also includes a sliding bar 90 which may be selectively positioned, via friction bolts or the like, to extend a predetermined distance, thus selectively abutting adjustable stop 76 and arresting thereby the rotation of the gripping arms during its downward rotation, as illustrated in FIG. 16.
It will be readily appreciated that when the elbow joints 16 (shown in FIG. 1) are formed in an elbow machine, the sections 12 are usually rotated slightly out of alignment with respect to one another. Each section 12 must therefore be rotated a different amount to have the proper alignment at the end of the rotation. As discussed above, the present invention envisions that one pair of gripping fingers 70 on each gripping arm 66 or 68 is mounted on a sliding bar 90 so that it may be stopped before the gripping arm is fully rotated down. When the gripping arm is rotated down, it is stopped at a different starting position to match the starting position of its respective elbow section. The gripping arm is therefore stopped at the position for the sliding gripping fingers to match the starting position of its respective elbow section. As the gripping arm rotates up, only those sections gripped by the fixed gripping fingers are initially rotated, until the gripping arm reaches the position that the sliding gripping fingers was stopped. As the rotation continues, the sliding gripping fingers, along with the fixed gripping fingers, now also rotate their respective sections through the rest of the rotation. At the end of the arm rotation each section is therefore in its proper, final position.
It will therefore be appreciated that the present invention provides a rotator for elbow workpieces which automatically performs the rotation of respective sections of the elbow workpiece, thereby automating what has traditionally been a laborious, difficult and time consuming process. Moreover, the present invention has envisioned that the elbow rotator may be provided in conjunction with an elbow forming machine, thus rotating each section of the elbow workpiece as it is formed, or alternatively, that a free standing elbow rotator may be utilized for simultaneously accomplishing rotation of all of the sections of an elbow workpiece after it has been formed.
While rotation apparatuses for automatically rotating interconnected sections of pre-formed cylindrical workpieces has been described in connection with FIGS. 1-16, another embodiment of the present invention involves the utilization of dual cut and bead slide blocks, as depicted in FIGS. 17-19.
Prior art elbow formation methods rely upon the manual manufacture of elbow sections for large diameter workpieces. Indeed, for workpieces larger than approximately 18″, each section of the elbow must be made separately and manually, and then manually joined together to form the finished elbow section of duct. Thus, the manipulation of larger-diameter cylindrical workpieces during the formation of the interconnected sections is oftentimes cumbersome, owing to the increased diameter of the workpiece, and must be preformed manually.
In general, and as discussed previously in conjunction with FIGS. 1-16, automatic elbow machines process straight tubes, that is, cylindrical workpieces, into segmented adjustable elbows. A cylindrical workpiece is inserted into the elbow machine around a center arbor and is clamped in a set of dies around the outside diameter. These known apparatuses utilize a revolving head mounted on top of the center arbor. A single slide block is mounted in a slot in the head, and rotates with the head. This single slide block is used to cut and form the interlocking elbow joints or sections. As known in the art, the slide block typically has a cutting wheel disposed at one distal end and a beading wheel disposed at the other distal end. As the revolving head rotates, the slide block is extended out in one direction to cut through the tube and then out in the other direction to bead the sections together.
When the slide block is extended out in either working position, the head is unbalanced, and this is only more of a concern on larger-diameter workpieces where the single slide block is inherently longer and heavier. That is, as the cutting and/or beading wheels are working the material, the cylindrical workpiece is pulled toward the slide where the slide block is either cutting or forming the material of the workpiece. Thus, the performance of known single-slide block forming apparatuses oftentimes suffers accordingly.
The present invention therefore proposes using a head having two identical and complimentary slide blocks, in order to better balance the forces exerted upon the workpiece during cutting and bead-formation operation. FIG. 17 illustrates a side view of a dual-slide block cutting and beading apparatus 100, according to one embodiment of the present invention. The dual-slide block cutting and beading apparatus 100 includes a frame 102, within which is supported an elevating assembly 104 for selectively moving a cylindrical workpiece along a vertical axis V. A dual slide-block head 106 is arranged adjacent an inclined work surface 108 of the frame 102, and operates in the manner to be discussed hereafter to cut and form interconnected section of the cylindrical workpiece.
It will be readily appreciated that the frame 102 and the elevating assembly 104 of the dual-slide block cutting and beading apparatus 100 perform substantially akin to those devices already known in the art, and so further detailed discussion as to their specific components and operation will be committed to the knowledge of those of such skill in the art. Suffice to say that the elevating assembly 104 may accept and index a portion of a cylindrical workpiece disposed within the dual-slide block cutting and beading apparatus 100, so as to present the cylindrical workpiece to the dual slide-block head 106 of the present invention.
FIGS. 18 and 19 illustrate a side and a partial cross-sectional top view, respectively, of the dual slide-block head 106, in accordance with one embodiment of the present invention. As shown in FIGS. 18 and 19, the dual slide-block head 106 includes a first and a second slide blocks, 110 and 112, disposed within matching slots 114 of the head 106.
Each of the slide blocks 110 and 112 will have a cutting wheel 116 disposed at one distal end, and a beading wheel 118 disposed at the other distal end thereof. The slide blocks 110 and 112 are mounted side by side in the head 106 and are positioned adjacent the inclined work surface 108. As best shown in FIG. 19, the slide blocks 110 and 112 will be oriented such that the cutting wheel-end 116 (and the beading wheel-end 118) of each slide block is disposed on opposite sides of the head.
That is, it is an important aspect of the present invention that the cutting wheel 116 of the first slide block 110 is oriented such that it is disposed on one lateral side of a drive gear assembly 120, while the cutting wheel 116 of the second slide block 112 is disposed on the other lateral side of the drive gear assembly 120. The beading wheel of the slide blocks 110 and 112 are also disposed on alternate lateral sides of the drive gear assembly 120, as shown in FIG. 19.
With the configuration as shown in FIG. 19, the dual slide-block head 106 effectively balances the forces incident upon a cylindrical workpiece as the slide blocks 110 and 112 are extended in opposite directions to cut and to bead the material of the cylindrical workpiece. A drive shaft 122 is located in the center of the dual slide-block head 106 and operates the drive gear assembly 120 in order to selectively drive matching gears 124 under each of the slide blocks 110 and 112. The gears 124 located under the slide blocks 110 and 112 will have a pin that is located at a distance from the center that will drive the slide blocks 110 and 112 back and forth in the head as it turns, thus alternatively forming both a cut in the material of the cylindrical workpiece, and also the bead that retains one cut portion to another, in a manner well known in the art.
As discussed generally above, using the two slide blocks 110 and 112 moving in opposite directions will keep the head 106 balanced and will contact the cylindrical workpiece on opposing sides to keep the cylindrical workpiece centered. Each wheel 116 and 118 of each of the slide blocks 110 and 112 will be doing half of the cutting or forming work, so each slide block 110 and 112 can therefore be extended and retracted faster to reduce the overall cycle time. Moreover, it has been discovered that he head 106 can also be rotated faster with the balanced weight of the two slide blocks 110 and 112 extended on opposite sides. In the end, a cut and seamed cylindrical workpiece, such as shown in FIG. 1, may be produced in less time, and with greater mechanical precision and within greater tolerances than would otherwise be capable with the known single-slide blocks typically employed in such machines.
Thus, the dual head elbow rotator apparatus shown in FIGS. 17-19 not only permits the automated manufacture of elbow sections of duct from a straight workpiece, but does so in a manner that balances the forces incident upon the workpiece during the formation process. In this manner, the manipulation of larger diameter cylindrical workpieces may be automated, while also meeting more exacting mechanical specifications.
Still further, the dual slide block 106 of the dual-slide block cutting and beading apparatus 100 produces less vibration, thus resulting in a reduced chance of producing slivers, as well as producing a faster cut and reduced total cycle time.
Still yet another embodiment of the present invention resides in equipping a elbow rotator apparatus that includes four (4) or more opposing cutting and beading slide blocks, preferably disposed every 90°, or the like.
It will of course be recognized that the automatic rotational assemblies described in connection with FIGS. 3-16 may be stand-alone devices, or may be advantageously combined with the dual slide block apparatuses discussed in connection with FIGS. 17-19. When so combined, the resultant assembly may quickly and efficiently form the interconnected sections of a cylindrical workpiece, while subsequently rotating these interconnected sections so as to form a desired configuration, such as an elbow configuration.
Referring now to FIGS. 20-32, the present invention may be embodied in a top-loading elbow cutter and rotator 1000 for working an elbow workpiece 24. The top-loading elbow cutter and rotator comprises a barstock frame 1001 supporting a lower casing 1012 defining a vertical axis and supporting an upper casing 1014 defining a tube axis. The elbow cutter and rotator also includes a top plate 1002 mounted to the upper casing. As can be seen by reference to FIG. 20, the tube axis defined by the upper casing is tilted at a tube angle about thirty (30) degrees “forward” from the vertical axis defined by the lower casing. The top plate includes a substantially circular through-hole 1021, which defines a cut axis, for receiving the elbow workpiece. As can best be seen by reference to FIG. 23, the cut axis defined by the top plate is further tilted at a cut angle of about fifteen (15) degrees forward from the tube axis defined by the upper casing 1014, for an overall tilt of about forty five (45) degrees between the cut axis and the vertical axis. The elbow cutter and rotator also includes a multi-diameter tool ring subassembly 1003 mounted on the top plate coaxial with the through-hole, a quick-change bead/lock shoe 1004 slidably connected to the tool ring, a mounted drum drive subassembly 1005 mounted within the frame coaxial with the tool ring subassembly, a baseplate 1016 mounted within the frame below the drum drive, an arbor column 1006 mounted on the baseplate and extending perpendicularly upward from the baseplate approximately to the center of through-hole in the top plate (and thereby being angled at about fifteen (15) degrees from the cut axis defined by the through-hole), a fifteen (15) degree arbor head subassembly 1007 rotatably mounted at the upper end of the arbor column within the through-hole (with the plane of the arbor head being parallel with the plane of the top plate), a quick-change slide block 1008 radially slidably mounted on the arbor head, and a control module 1015 for coordinating operations of the tool ring, the drum drive, the arbor column, and the arbor head. The tool ring, the drum drive, the arbor column, the arbor head, and the slide block cooperate to cut the elbow workpiece into angled sections, to bead the section edges, and to rotate the sections to form an “elbow”, “bent leg”, or partial “donut” of ductwork including a plurality of bends ranging from zero (0) to thirty (30) degrees.
Preferably, the tool ring 1003 is adapted to receive one of several quick-change bead/lock shoes 1004, the drum drive 1005 includes diametrically adjustable components, and the arbor head subassembly 1007 is adapted to receive one of several interchangeable slide blocks 1008, for handling, cutting, and forming several different diameters of elbow workpieces (seamed sheet metal tubes or thin-walled seamless metal pipes). For example, the tool ring 1003 and the drum drive 1005 can be adjustable for cylinder diameters from four (4) to seven (7) inches, while interchangeable bead/lock shoes 1004 and slide blocks 1008 can be provided at half-inch (0.5″) diameter increments.
Referring to FIG. 28, the multi-diameter tool ring subassembly 1003 includes a base ring 1301, a plurality of mounting brackets 1302 extending outward from the base ring for mounting the base ring to the upper plate 1002, a slotted ring 1303 rotatably mounted within the base ring, a ring motor 1304 drivingly connecting the slotted ring to the base ring via a right-angle worm-and-pinion 1305 and a curved rack 1306, and at least one bead/lock shoe 1004 radially slidingly mounted on the base ring and operatively connected to a spiral slot of the slotted ring. The tool ring subassembly 1003 is designed to handle a range of OD part (for example, 4″ thru 7″ OD elbows) with quick tool changeover. For example the spiral slots of the slotted ring 1303 can be angled to shift each bead/lock shoe 1004 from a 4″ OD position to a 7″ OD position by a ninety (90) degree clockwise rotation of the slotted ring. The slotted disc design allows for high load carrying in both the lock shoe tools and the lock part tools by simple rotation of a disc as to move the set of tools to the location necessary to perform their function.
Referring to FIG. 29, alternatively, a sequence of interchangeable bead/lock shoes 1004 can be provided in sequential base OD dimensions of 4″, 5″, and 6″, with the slots of the slotted ring being angled to accommodate a range of incremental bead/lock shoe positions from, for example, −0.1″ OD to +1.1″ OD. Thus a combination of bead/lock shoe and slot position can be selected to accommodate any elbow workpiece size ranging from 4″ to 7″ OD. Each of the interchangeable bead/lock shoes 1004 includes a tracked plate 1401 supporting a slotted block 1402. The slotted block is covered by a cover plate 1403 and is housed between grooved sideplates 1404 a and 1404 b. The slotted block is engaged by a pin (not shown) to the spiral slot of the slotted ring 1303 of the tool ring assembly 1003, where the slot is so tapered as to retract and extend each shoe when desired by the rotation of the slotted disc. Each bead/lock shoe includes a beading roller head 1405 a and a cutting roller head 1405 b holding beading roller 1406 and a cutting roller 1407, respectively. The roller heads are adjustable within the bead/lock shoe with reference to the slotted block by shims (not shown) independently of the fixed offset slider. The bead/cutter tool set has been simplified, where most components other then the “slide spacer” and “slide base” are common regardless of OD part sizes, reducing the overall cost of a multi OD machine setup.
Referring to FIG. 30, the drum drive assembly 1005 includes a support flange 1501, three slide bearings 1502 and lockrings 1521 mounted at corners of the support flange, an irising clamp assembly 1503 mounted within the support flange, a multi-size locking drum assembly 1504 mounted coaxially with the irising clamp assembly below the support flange, a pulley drivetrain 1505 connecting the locking drum 1504 to a drum motor (not shown) mounted on a motor bracket 1506. The irising clamp assembly includes an outer ring 1531 held to the support flange 1501 by clamps 1532, an inner ring 1533 driven within the outer ring by the locking drum assembly 1504, and a plurality of clamp heads 1534 mounted to the outer ring and slidable in spiral tracks of the inner ring. The multi-diameter part retainer drum 1504 includes a plurality of various sized rings 1541 that are movable by the driven sprocket 1551 of the pulley drivetrain, the uppermost ring being connected to the omni-directional irising clamp assembly 1503 and the lowest ring being connected to the driven sprocket. The drum drive is designed to rotate continuously in either direction. This allows the drum drive to be used as a secondary rotation device, rather than having to mount a second motor outside the machine for pre-bending elbows. The inner and outer rings and the spiral tracks of the irising clamp assembly 1503 are arranged so that, as the locking drum assembly 1504 rotates in one direction, the clamp heads expand from a minimal diameter toward a maximal diameter, and then back toward the minimal diameter, as the part retainer drum assembly 1504 is rotated continuously in either direction by the pulley drive; reversing the part retainer drum rotation causes the irising clamp to expand from its present diameter, then contract again. This radial oscillating motion eliminates having to dismantle any tooling within the body of the machine to change elbow workpiece part diameter. Since the drum drive 1005 includes a multi-size locking drum assembly 1504, the only tool changeouts for changing elbow sizes are the bead/lock shoe mounted onto the tool ring subassembly and the slide block 1008 mounted onto the arbor head 1007.
Referring to FIG. 31, the arbor column 1006 is mounted through and substantially perpendicular to the baseplate 1016. As can best be seen by referring back to FIG. 24, the baseplate 1016 is substantially perpendicular to the tube axis, that is, angled at about fifteen (15) degrees from the top plate 1002 and the tool ring 1003. Consequently the arbor column 1006 is disposed substantially parallel with the tube axis, angled at about fifteen (15) degrees from the cut axis defined by the through-hole 1021. The arbor column serves as a locating post for the elbow workpiece 24, which is inserted into the through-hole over the arbor column. Referring again to FIG. 31, the arbor column also supports and houses the arbor head 1007 and the associated drive train components, as further discussed below with reference to FIG. 32.
Referring to FIG. 32, the arbor head 1007 is designed to have a fifteen (15) degree tilt upper surface with a jointless drive train extending slantwise across the arbor axis defined by the arbor head subassembly. This is by contrast to previous implementations where universal joints were used and resulted in significant vibrations due to continual slow-and-go accelerations. The jointless drive train provides much less vibration and thereby reduces the creation of slivers, enhancing safety and finished elbow quality. The fifteen (15) degree tilt upper surface is substantially parallel with the tool ring 1003. The arbor head includes an outer shell 1701, upper and lower drive train portions 1702 a, 1702 b respectively, a pinhead 1704, a split support block 1705. The outer shell includes a ring bushing 1711 for enhanced rotation of the split support block relative to the outer shell, a sequence of bushings 1712, 1713, 1714 for locating the upper drivetrain 1702 a, at least one side groove 1715, an offset hole 1716, a bottom plate 1717. The upper drive train 1702 a includes a top shaft 1721 protruding through the split support block, a midshaft 1722, assembly components 1723, and a lower shaft 1726. The pinhead is mounted to the upper end of the top shaft and rests on the split support block. The top shaft extends downward from the pin head parallel with the midshaft and at a fifteen (15) degree angle from the centerline of the outer shell and the arbor column 1006. The top shaft defines an arbor axis substantially coincident with the cut axis defined by the through-hole 1021; the pinhead rotates about the arbor axis. The midshaft is offset across the centerline of the arbor column from the top shaft and at its upper end is operatively connected to the top shaft by a first offset gear pair 1724 and 1725 carried on the top shaft and on the midshaft, respectively. The midshaft at its lower end is operatively connected to the lower shaft by a second offset gearset 1727 carried on the midshaft and on the lower shaft, respectively, so that the lower shaft also is offset from the midshaft across the centerline of the outer shell and is doubly offset from the top shaft. Like the top shaft and the midshaft the lower shaft extends at a fifteen (15) degree angle across the centerline of the arbor column 1006 and the lower end of the lower shaft protrudes through the shell of the arbor column. The lower shaft carries a beveled pinion 1726 at its lower end. The beveled pinion is beveled at a fifteen (15) degree angle so that the flanks of the pinion teeth extend substantially parallel with the centerline of the arbor column. The beveled pinion is driven by a straight-flanked (zero bevel) ring or bull gear also having tooth flanks extending substantially parallel with the centerline of the arbor column, thus permitting slight axial adjustments of the arbor column 1006 to compensate for varying thicknesses of sheet metal being worked without disengagement of the arbor head drivetrain. The ring gear or bull gear can be powered directly or indirectly by an electric motor. As will be appreciated by those of ordinary skill, the beveled teeth of the pinion mean that upward adjustment of the arbor head for thinner sheet metal consequently will result in slightly faster rotation of the pinhead, while downward adjustments for thicker sheet metal will result in slightly slower rotation of the pinhead. This “fine tone” linear travel of the arbor column 1006 adjusts the cutter disc of the slide block 1008 to a defined gap (based on part wall thickness) from the cutter blade of the bead/lock shoe 1004. This adjustment allows for different wall thicknesses regardless of OD, as to reduce all “metal shaving”. The split support block permits rapid change-out of the quick-change slide block 1008 so that the arbor head can be used for different sizes of sheet metal cylinders, eliminating previously complex retooling of an entire arbor head required in order to changeover to a different part size.
Referring back to FIG. 29, the bead/lock shoes 1004 can be made interchangeable with the slide blocks 1008 for use on the arbor head 1007. The slide block includes first and second tool shoes 1805 a, 1805 b, having a cutting wheel 1806 in one shoe and a beading wheel 1807 in the other shoe. With the slide block mounted on the pinhead 1704, the wheels 1806 and 1807 are disposed substantially coplanar with their corresponding rollers 1406 and 1407. The offset pin 1741 on the pinhead 1704 drives the slide block 1008 back and forth to provide cutting and beading steps successively, with each of the wheels 1806, 1807 being successively exposed to perform these operations as the pinhead rotates. Alternatively, the dual slide block head 106 (shown in FIGS. 18 and 19) can be used as the slide block 1008. In either embodiment, the top shaft 1721 of the upper drivetrain 1702 is positioned to extend through the support block 1705 and is coupled to the pinhead 1704 for driving the slide block. To cut and preform the workpiece 24, the offset pin 1741 is initially centered within the slot of the slide block, and the cutting wheel is then moved out into engagement with the interior of the work piece, and cooperates with the cutting roller 1406 of the tool shoe 1004 to cut the work piece. To couple the cut portions, the slide block moves to expose the beading wheel after the cut pieces of the tube are positioned in overlapping relationship. In cooperation with the beading roller 1407, the bead coupling is formed between adjacent cut sections.
While the invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various obvious changes may be made, and equivalents may be substituted for elements thereof, without departing from the essential scope of the present invention. For example, although three distinct embodiments have been shown and described, aspects of the three embodiments can be combined in various ways without undue experimentation. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention includes all embodiments falling within the scope of the appended claims.

Claims

1. An apparatus for forming an elbow from a sheet metal tube with an outer diameter within a predetermined range of diameters, said apparatus comprising:

a frame defining a vertical axis and a tube axis offset from the vertical axis by a tube angle;

a top plate, mounted to the top of said frame, with a through-hole defining a cut axis offset from the tube axis by a cut angle;

a tool ring rotatably mounted to said top plate substantially coaxial with and surrounding the through-hole;

a tool shoe slidably mounted to said tool ring for radial motion toward and away from the cut axis across the through-hole, according to the diameter of said sheet metal tube, rotation of said tool ring within said top plate causing the radial motion of said tool shoe;

a baseplate supported within said frame below said top plate and substantially perpendicular to the tube axis;

a locking drum assembly supported within said frame between said top plate and said baseplate and substantially coaxial with the tube axis, said locking drum assembly including clamp heads for gripping said sheet metal tube, the clamp heads being radially movable within said locking drum assembly toward and away from the tube axis according to the diameter of said sheet metal tube, and the locking drum assembly being rotatably movable within said frame by means of a locking drum motor;

an arbor column mounted to said baseplate substantially parallel with the tube axis;

an arbor head mounted to said arbor column, said arbor head including a pinhead rotatable about an arbor axis substantially parallel with the cut axis;

a slide block slidably mounted on said arbor head, rotation of the pinhead causing radial motion of said slide block toward and away from the arbor axis; and

a jointless drivetrain extending from the pinhead of said arbor head through said arbor column, substantially parallel with the cut axis and to the arbor axis, and operatively connecting the pinhead to a motor.

2. The apparatus as claimed in claim 1, wherein the tube angle is about thirty (30) degrees.

3. The apparatus as claimed in claim 1, wherein the cut angle is about fifteen (15) degrees.

4. The apparatus as claimed in claim 1, wherein the cut angle is about twenty two and one half (22.5) degrees.

5. The apparatus as claimed in claim 1, wherein said tool shoe is selected from one of a plurality of tool shoes interchangeably connectable to said tool ring, according to the diameter of said sheet metal tube.

6. The apparatus as claimed in claim 1, wherein said locking drum assembly includes an irising clamp having an outer ring and an inner ring, the clamp heads being slidably connected to the outer ring and slidably pivotally connected to the inner ring for radially oscillating motion as said locking drum assembly rotates within said frame continuously in a single direction about the tube axis.

7. The apparatus as claimed in claim 1, wherein said jointless drivetrain includes a sequence of offset shafts extending substantially parallel with the cut axis operatively connected by offset gearsets, the lowest shaft of the sequence terminating in a beveled pinion gear having tooth flanks that are substantially parallel with the tube axis at a location where the beveled pinion gear meshes with a driving gear.

8. The apparatus as claimed in claim 1, wherein said tool ring includes an outer ring clamped to said top plate, a slotted ring having a spiral slot and rotatably mounted within the outer ring, and a motor operatively connecting the slotted ring to the outer ring, and said tool shoe is radially slidably mounted to the outer ring of said tool ring and is slidably engaged with the spiral slot of the slotted ring, so that rotation of the slotted ring within the outer ring causes inward or outward radial motion of said tool shoe.

9. The apparatus as claimed in claim 8, wherein said spiral slot provides for about one (1) inch radial motion of said tool shoe.

10. The apparatus as claimed in claim 8, comprising first, second and third tool shoes respectively engaged with first, second, and third spiral slots equally circumferentially spaced around the slotted ring of said tool ring.

11. The apparatus as claimed in claim 8, further comprising a control module operatively connected to selectively actuate the motor of said jointless drivetrain, the motor of said locking drum assembly, and the motor of said tool ring.

12. The apparatus as claimed in claim 11, wherein at least one of the motors is a hydraulic motor.

13. The apparatus as claimed in claim 11, wherein said control module is programmed to cut and bead three fifteen (15) degree joints at substantially equal spacings along said sheet metal tube, upon insertion of said tube through the through-hole of said top plate to contact said baseplate.

14. The apparatus as claimed in claim 13, wherein said control module is actuated to execute its program by contact of said tube against said baseplate.

15. The apparatus as claimed in claim 13, said arbor column further including a limit switch, wherein said control module is actuated to execute its program by actuation of the limit switch.

16. The apparatus as claimed in claim 1, wherein said arbor column is movable relative to said baseplate along the tube axis, said jointless drivetrain being driven by a beveled pinion gear having tooth flanks that are substantially parallel with the tube axis at a location where the beveled pinion gear meshes with a driving gear.

17. The apparatus as claimed in claim 1, wherein the tube angle is negligibly small such that the tube axis is parallel with the vertical axis.