DIE ASSEMBLY FOR USE IN AN APPARATUS FOR FORMING A WORKPIECE
A die assembly for forming a workpiece includes a support clamp, a first clamp that is movable relative to the support clamp to engage a first portion of the workpiece, and a second clamp that is movable relative to the support clamp to engage a second portion of the workpiece. A forming punch is movable relative to the support clamp after the first clamp and the second clamp have been moved to form the workpiece.
This invention relates in general to an apparatus for forming a workpiece to have a desired shape. In particular, this invention relates to an improved die assembly for use in such an apparatus for forming a workpiece that prevents the formed workpiece from being undesirably retained on the die assembly.
A wide variety of apparatuses are known in the art for forming workpieces to have a desired shape. For example, mechanical presses are well known apparatuses that are commonly used to manufacture a wide variety of workpieces including, for example, relatively large or thick-walled workpieces such as side rails, cross members, and other components for vehicle frame assemblies. A typical mechanical press includes a stationary portion (typically referred to as a bed) having a first die section of a die assembly secured thereto, a movable portion (typically referred to as a ram) having a second die section of the die assembly secured thereto, and an actuating mechanism for selectively moving the ram toward and away from the bed. When the ram is moved toward the bed, the first and second die sections of the die assembly engage the workpiece and exert forces thereon to mechanically form it into a desired shape. When the ram is moved away from the bed, the first and second die sections are moved apart from one another to allow the formed workpiece to be removed and the next workpiece to be formed to be inserted.
It is often desirable to form workpieces to have relatively complex shapes that can include, for example, stiffening features or mounting bosses at various locations. These relatively complex shapes may, after formation, cause portions of the formed workpiece to be clamped or otherwise retained on portions of the die assembly. Such retention of the formed workpiece on the die assembly is usually undesirable because it can inhibit the removal of the formed workpiece from the die assembly, thereby increasing the amount of time and effort necessary to complete the forming cycle. Thus, it would be desirable to provide an improved die assembly for use in an apparatus for forming a workpiece that prevents the formed workpiece from being undesirably retained on the die assembly.
SUMMARY OF THE INVENTIONThis invention relates to an improved die assembly for use in an apparatus for forming a workpiece that prevents the formed workpiece from being undesirably retained on the die assembly. The die assembly includes a support clamp, a first clamp that is movable relative to the support clamp to engage a first portion of the workpiece, and a second clamp that is movable relative to the support clamp to engage a second portion of the workpiece. A forming punch is movable relative to the support clamp after the first clamp and the second clamp have been moved to form the workpiece.
Various aspects of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.
Referring now to the drawings, there is illustrated in
The illustrated workpiece 22 includes a first leg 24 having an uneven profile or complex geometry that includes a stiffening channel 24a or other protruding feature, boss, fin, rib, or structure. The illustrated workpiece 22 also includes a second leg 26, which is shown as an extending side from the first leg 24. As will be explained in detail below, the second leg 26 will be formed by the die assembly 10 to have a desired shape. The first leg 24 of the illustrated workpiece 22 has three locating apertures 28 formed therethrough, although any number of such locating apertures 28 (or none at all, if desired) may be provided.
The illustrated locating apertures 28 are adapted to be engaged by respective movable pin assemblies 30. Each of the movable pin assemblies 30 is supported on and extend beyond an upper surface of a support clamp 32. The structure and operation of the support clamp 32 and the movable pin assemblies 30 will be explained below.
The illustrated support clamp 32 is supported on the base 11 for lateral movement relative thereto for selective engagement with the second leg 26 of the workpiece 22. However, the support clamp 32 may be supported for any desired movement relative to the base 11. The illustrated support clamp 32 includes at least one pin slot 34 that engages the movable pin assembly 30. The illustrated pin slot 34 is an elongated slot that allows the support clamp 32 to move relative to the movable pin assembly 30. The relative fit between the pin slot 34 and the movable pin assembly 30 provides a sufficient locating tolerance to orient the workpiece 22 within the die assembly 10. The support clamp 32 may include a cam follower 36 that cooperates with a cam actuator 38 to effect the selective movement of the support clamp 32 relative to the base 11 in the manner described below. Alternatively, the support clamp 32 can be moved relative to the base 11 by any desired mechanism. For example, the support clamp 32 can be moved relative to the base 11 by means of a hydraulically driven ram, a reciprocating rod and clevis, an oscillating actuator, a linear motor, a rack and pinion drive, and the like.
A forming punch 40 is supported on the base 11 for movement relative thereto. The forming punch 40 may be moved by a cam assembly 42, which may be embodied as any device that can move the forming punch 40 in order to deform the workpiece 22 as desired. The cam assembly 42 may be similar to the clamping actuator examples mentioned above. The forming punch 40 includes a leading edge 44 that cooperates with a forming recess 46 provided in the support clamp 32. The cooperating leading edge 44 and the forming recess 46 are moved across the base 11 from an opened position, shown in
Initially, as shown in
In operation, the workpiece 22 is placed in the die assembly 10 by engaging the pin nose 50 through the locating aperture 28, as shown in
As the first clamp 12 is being brought into contact with the first leg 24 of the workpiece 22, the support clamp 32 is moved to the closed position illustrated in
Referring now to
The steps to release the finished part 64 from the die assembly 10 may be conducted in the reverse order from the clamping steps described above, though such is not required. Alternatively, the load applied by the first clamp 12 may be reduced prior to retracting the leading edge 44 from engagement with the forming recess 46. This may reduce the load required to move the leading edge 44 from engagement with the flange 62. Once the leading edge 44 is pulled past the flange 62, the second clamp 20 is moved away from the remainder of the second leg 26 of the finished workpiece 64. The first clamp 12 is further retracted from contact with the finished workpiece 64 so that the movable pin assemblies 30 can articulate from the pin slots 34 and push the finished workpiece 64 out of the die assembly 10. As the movable pin assemblies 30 eject the finished workpiece 64 from the die assembly 10, automated handling equipment may be used to move the finished workpiece 64 onto the next operation. The cycle is then ready to accept another workpiece 22 and restart the forming process.
The principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.
Claims
1. A die assembly for forming a single workpiece comprising:
- a support clamp;
- a first clamp that is movable relative to the support clamp to engage a first portion of a single workpiece;
- a second clamp that is movable relative to the support clamp to engage a second portion of the single workpiece; and
- a forming punch that is movable relative to the support clamp after the first clamp and the second clamp have been moved to form a flange on the end of the second portion of the single workpiece, the flange being folded inward of the single workpiece.
2. The die assembly of claim 1 wherein the support clamp includes a recess that cooperates with the forming punch to form the single workpiece.
3. The die assembly of claim 1 wherein the support clamp includes a pin slot disposed about a portion of a movable pin assembly, the support clamp being movable relative to the movable pin assembly.
4. The die assembly of claim 1 wherein the support clamp includes a cam follower that is selectively engaged by a cam driver to move the support clamp from an opened position to a closed position.
5. The die assembly of claim 1 wherein the support clamp includes a cam follower that is selectively engaged by a cam driver to move the support clamp from an opened position to a closed position and to support the support clamp against the movement of the forming punch.
6. The die assembly of claim 3 wherein the movable pin assembly is supported on a resilient member for biased movement.
7. The die assembly of claim 6 wherein the resilient member is a nitrogen charged spring.
8. The die assembly of claim 3 wherein the movable pin assembly is located above the support clamp surface such that the single workpiece does not engage the support clamp.
9. The die assembly of claim 1 wherein the first clamp assembly includes a resilient member that resiliently supports the floater clamp within the rigid clamp.
10. The die assembly of claim 9 wherein the resilient member is a nitrogen charged spring.
11. A die assembly for forming a feature onto a single component comprising:
- a base having at least one movable pin assembly that is biased in an extended position;
- a support clamp engaging the base for relative movement therewith;
- a first clamp assembly that is movable relative to the support clamp and having a rigid clamp and a floater clamp, the first clamp assembly further having a pin recess adapted to engage a portion of the movable pin assembly;
- a forming punch engaging the base for relative movement therewith and having a leading edge that cooperates with the support clamp to form a feature; and
- a second clamp that is movable relative to the forming punch, the second clamp cooperating with the support clamp to engage a portion of a single component therebetween, wherein the feature is a flange on the end of the portion of the single component, the flange being folded inward of the single component.
12. The die assembly of claim 11 wherein the support clamp includes a recess that cooperates with the forming punch to form the single component.
13. The die assembly of claim 11 wherein the support clamp includes a pin slot disposed about a portion of the movable pin assembly, the support clamp being movable relative to the movable pin assembly.
14. The die assembly of claim 11 wherein the support clamp includes a cam follower that is selectively engaged by a cam driver to move the support clamp from an opened position to a closed position.
15. The die assembly of claim 11 wherein the support clamp includes a cam follower that is selectively engaged by a earn driver to move the support clamp from an opened position to a closed position and to support the support clamp against the movement of the forming punch.
16. The die assembly of claim 11 wherein the movable pin assembly is supported on a resilient member for biased movement.
17. The die assembly of claim 16 wherein the resilient member is a nitrogen charged spring.
18. The die assembly of claim 11 wherein the movable pin assembly is located above the support clamp surface such that the single component does not engage the support clamp.
19. The die assembly of claim 11 wherein the first clamp assembly includes a resilient member that resiliently supports the floater clamp within the rigid clamp.
20. The die assembly of claim 19 wherein the resilient member is a nitrogen charged spring.
21. A die assembly for forming a flange onto a single workpiece comprising:
- a base having at least one movable pin assembly biased in an extended vertical position;
- a support clamp engaging the base for relative horizontal movement therewith;
- a first clamp assembly vertically movable relative to the support clamp and having a rigid clamp, a floater clamp, and a pin recess adapted to engage a pin nose of the vertically movable pin assembly;
- a forming punch engaging the base for relative horizontal movement therewith and having a leading edge; and
- a second clamp horizontally movable relative to the forming punch, the second clamp cooperating with the support clamp to engage a portion of a single workpiece therebetween and the leading edge cooperating with the support clamp to form a flange on the end of the single workpiece portion.
22. The die assembly of claim 21, wherein the flange is folded inward of the single workpiece.
Type: Application
Filed: Sep 1, 2008
Publication Date: Mar 4, 2010
Inventors: Rahul Kulkarni (Wyomissing, PA), Robert J. Mills, III (Womelsdorf, PA), Jan C. Turczynski (Hopkinsville, KY)
Application Number: 12/202,426
International Classification: B21D 22/22 (20060101); B21D 24/04 (20060101);