DRAW PRESS WITH A FIXED DRAW PUNCH AND A FLOATING DRAW PUNCH

Abstract

A machine is disclosed for producing a deep drawn part and a shallow drawn part from sheet metal blanks in a single action draw press. A floating draw punch and a fixed draw punch are provided. The first draw die forms a part that is drawn over the fixed draw punch while the second blank does not begin forming the second part until the floating draw punch bottoms out on the bed of the press. The floating draw punch moves with the binder ring until the additional draw depth required to form the deep drawn part is essentially equal to the draw depth of a shallow drawn part. A process for producing multiple unattached sheet metal parts in a single action draw press is also disclosed wherein a first sheet metal part has a draw depth D1 and a second sheet metal part has a draw depth D2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a die set for a single-action draw press that has two stations for forming two different parts in the same draw operation;

FIG. 2 is a diagrammatic cross-sectional view showing a portion of a single-action draw press for forming a deep drawn part and a shallow drawn part wherein the deep drawn part has a fixed punch, while the shallow drawn part has a floating punch, wherein the apparatus is shown with the draw dies engaging blanks that are supported by the binder ring and punches;

FIG. 3 is a view similar to FIG. 2, but showing the deep drawn part being formed by the fixed punch while the floating punch used to form the shallow drawn part is shifted toward the press bed;

FIG. 4 is a view similar to FIGS. 2 and 3, but showing the deep drawn part being more fully formed and the floating punch bottomed on the bed of the press;

FIG. 5 is a view similar to FIGS. 2-4 showing the deep drawn part and the shallow drawn part being nearly completely formed with the punch for the shallow drawn part drawing one of the blanks to a lesser extent than the fixed punch of the deep drawn part; and

FIG. 6 is a view similar to FIGS. 2-5 showing the deep drawn part and shallow drawn part completely formed in the die cavity.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Referring to FIG. 1, a die set 10 is shown in its closed position with the upper die shoe 12 in engagement with the lower die shoe 14.

Referring to FIG. 2, a first draw die 18 and a second draw die 20 are connected to the ram 22 of a single action draw press. A first draw punch 24 and a second draw punch 26 are shown in conjunction with the bed 28 of the single action draw press. The first draw punch 24 is fixedly secured to the bed 28. The second draw punch 26 is initially movable relative to the bed 28. A first binder ring 30 and a second binder ring 32 are moveably connected to the bed 28 by press cushion pins 36. The press cushion pins 36 may be cylindrical bars that are supported on the press cushion 37 that guide the upward and downward movement of the first and second binder rings 30 and 32 relative to the bed 28 of the press. Floating draw punch press cushion pins 38 moveably support the second draw punch 26 on the press cushion for movement relative to the bed 28 of the press. A bottoming surface 40 is provided on the second draw punch 26 that engages the bed 28 of the press when the forming operation of the second draw punch 26 commences, as will be described more fully below.

A first blank 42 is loaded between the first draw die 18 and the first draw punch 24 that is encompassed by the first binder ring 30. A second blank 44 is loaded between the second draw die 20 and second draw punch 26 that is encompassed by the second binder ring 32. When the first blank 42 is loaded into the die set 10, it is supported on the first draw punch 24 and the first binder ring 30 so that it does not sag prior to the forming operation. Likewise, the second blank 44 is supported by the second draw punch 26 and second binder ring 32. The second draw punch 26 may also be referred to as a floating draw punch.

In the position shown in FIG. 2, the first and second draw dies 18 and 20 are shown engaging in the first and second blanks 42 and 44 to hold them against the first and second binder rings 30 and 32. The central portion of the first and second blanks 42 and 44 are supported by the first draw punch 24 and the second draw punch 26, respectively. As shown in FIG. 2, the bottoming surface 40 of the second draw punch is spaced from the bed 28. Draw depth D₁ for the first draw die 18 and draw depth D₂ of the second draw die 20 are also indicated in FIG. 2.

Referring to FIG. 3, the first draw die 18 is shown as it begins to form the blank 42 over the first draw punch 24. The periphery of the blank 42 is clamped between the first draw die 18 and the first binder ring 30 as the central portion of the blank 42 is drawn over the first draw punch 24. At the same time, the second draw die 20 is shown in engagement with the second binder ring 32. The second binder ring 32 and the second draw punch 26 are supported on press cushion pins and the press cushion and are shifted downwardly towards the bed 28 of the press. No substantial forming of the second blank 44 occurs during this phase of the production cycle because the second draw punch 26 moves downwardly with the second binder ring 32 on the press cushion pins 38 and 36, respectively.

Referring to FIG. 4, the process is shown at the point at which the first draw die 18 has traveled a distance corresponding to the difference between draw depth D₁ and draw depth D₂. At this point, the bottoming surface 40 initially engages the bed 28 of the press. The floating draw punch 26 stops moving while the second binder ring 32 remains free to continue moving downwardly with the second draw die 20 relative to the second, or floating, draw punch 26.

Referring to FIG. 5, the first and second draw dies 18 and 20 are shown having been moved to a point that is near the bottom of the press cycle. Both of the blanks 42 and 44 have been substantially formed with a small degree of formation still remaining. The first and second draw dies 18 and 20 and the first and second binder rings 30 and 32 are shifted downwardly relative to the first and second draw punches 24 and 26 resulting in the simultaneous drawing of the two parts.

Referring to FIG. 6, the process is shown at the point at which the first draw die 18 and the second draw die 20 have traveled a distance corresponding to drawn depth D₁. The first and second blanks 42 and 44 are shown fully formed with the first blank being formed in a deep draw cavity 48 defined by the first draw die 18. The second blank 44 is shown fully formed in the shallow draw cavity 50 of the second draw die 20. The binder rings 30 and 32 and floating draw punch 26 are shown in their fully closed position with the parts having been formed from the first and second blanks 42 and 44. The press begins to open and return to its initial position with the first and second draw dies 18 and 20 being spaced from the first and second binder rings 30 and 32 and the draw punches 24 and 26 to permit unloading the formed parts and loading of a new set of blanks. The cycle is then repeated to form additional parts.

While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.

Claims

1. A machine for producing a deep drawn part and a shallow drawn part from first and second sheet metal blanks in a single action draw press, comprising: first and second draw dies secured to a ram of the draw press, wherein each of the draw dies have different draw depths;a first draw punch is secured to a bed of the draw press, a second draw punch is movably supported on a first set of press cushion pins, wherein the first and second draw punches each engage one of the blanks and draw one of the blanks to the draw depth of one of the draw dies;first and second binder rings are movably supported on a second set of press cushion pins, wherein each of the binder rings is disposed around one of the first and second draw punches; andwherein the second draw punch is moveable relative to the first draw punch and to the bed of the draw press until the second draw punch bottoms out on the bed.

2. The machine of claim 1 wherein the first draw punch further comprises a deep draw punch and the second draw punch comprises a shallow draw punch, wherein the shallow draw punch is not as deep as the deep drawn punch.

3. The machine of claim 1 wherein the first draw punch further comprises a fixed draw punch and the second draw punch comprises a floating draw punch.

4. The machine of claim 3 wherein the fixed draw punch is fixedly connected to the bed of the press while the first binder ring moves relative to the fixed draw punch, and wherein the floating draw punch and the second binder ring move until an additional draw depth required to form a deep drawn part is essentially equal to a draw depth of the floating draw punch, whereupon the floating draw punch bottoms out and the ram continues forming the deep drawn part and begins forming the shallow drawn part.

5. The machine of claim 4 wherein the fixed punch is fixedly attached to the bed of the draw press.

6. The machine of claim 1 wherein the first and second binder rings are engaged by the draw dies that move the binder rings downwardly on the second set of press cushion pins.

7. The machine of claim 1 wherein the draw punches and the two binder rings support the two blanks after the blanks are loaded into the draw press.

8. A process for producing multiple unattached sheet metal parts in a single action draw press having single ram that reciprocates relative to a press bed, wherein a first sheet metal part has a draw depth D1 and a second sheet metal part has a draw depth D2, wherein D1 is greater than D2 , the process comprising the steps of: loading a first blank and a second blank into the draw press with the first and second blanks each being disposed on top of a binder ring and above a draw punch, wherein the draw punch supporting the first blank is a fixed draw punch that is secured to a bed of the draw press and the draw punch supporting the second blank is a floating draw punch that is secured within a lower die shoe and is supported by a plurality of press cushion pins for movement relative to the bed of the draw press;lowering the ram that supports a draw die for each of the first part and second part that each engage one of the first and second blanks and clamp the blanks to one of the binder rings;partially drawing the first blank over the fixed draw punch and moving the binder supporting the first blank downwardly;shifting the binder and the floating draw punch supporting the second blank downwardly during the step of partially drawing the first part;bottoming the floating draw punch on the bed of the draw press;drawing the first part and the second part until both parts are fully drawn;returning the draw dies, the binders and the floating draw punch to the loading position; andunloading the first and second parts from the draw press.

9. The process of claim 8 wherein one of the draw dies forms a deep drawn part and the other draw die forms a shallow drawn part, wherein the shallow drawn part is not as deep as the deep drawn part.

10. (canceled)

11. The process of claim 8 wherein the floating draw punch moves with the binder ring until the added draw depth required to form a deep drawn part is essentially equal to the draw depth of a shallow drawn part, wherein the floating punch bottoms out on the bed of the press and the ram continues forming the deep drawn part and the shallow drawn part.

12. The process of claim 11 wherein the fixed punch is fixedly attached to the bed of the draw press.

13. The process of claim 8 wherein the two binder rings are engaged by the draw dies that move the binder rings downwardly.

14. The process of claim 8 wherein the draw punches and the binder rings support the two blanks as the blanks are loaded into the draw press.

15. A method of manufacturing a deep drawn sheet metal part and a shallow drawn sheet metal part that is not as deep as the deep drawn part at the same time in a draw press, the draw press being provided with at least two draw dies that are attached to a ram, the draw press being provided with a fixed draw punch that is fixedly attached to the bed of the draw press, and a floating draw punch that is initially supported on a first set of movable pins that are supported by a press cushion, and the draw press being provided with at least two binder rings that are attached to a second set of pins that are movable relative to the bed of the draw press, the method comprising: loading first and second blanks into the draw press with the blanks being disposed on top of the binder rings and above the draw punches;lowering the draw dies to engage both of the blanks and clamp the blanks to both of the binder rings;partially drawing the deep drawn part over the fixed draw punch and moving the draw die and the binder of the deep drawn part downwardly;shifting the binder of the floating draw punch and floating draw punch of the shallow drawn part downwardly during the step of partially drawing the deep drawn part;bottoming the floating draw punch on the bed of the draw press;drawing the deep drawn part and the shallow drawn part after the floating draw punch is bottomed on the die bed until both parts are fully drawn;returning the draw dies, the binders, and floating draw punch to the loading position; andunloading the parts from the draw press.

16. The method of manufacturing of claim 15 wherein the at least two draw dies further comprise a draw die for a deep drawn part and a draw die for a shallow drawn part.

17. The method of manufacturing of claim 15 wherein the floating draw punch initially moves relative to the bed of the draw press with the binder of the floating punch before bottoming on the bed of the draw press.

18. The method of manufacturing of claim 15 wherein the floating draw punch moves with the binder ring until a draw depth required to finish forming the deep drawn part is essentially equal to a draw depth of the shallow drawn part, wherein the floating punch bottoms out and the ram continues forming the deep drawn part and the shallow drawn part.

19. The method of manufacturing of claim 15 wherein the binder rings are engaged by one of the draw dies that move the binder rings downwardly.

20. The method of manufacturing of claim 15 wherein the draw punches and the two binder rings support two blanks after the blanks are loaded into the draw press.