US3053210A - Pierce and flange die assembly - Google Patents

Description

Sept. 11, 1962 C. M. KOWALSKI PIERCE AND FLANGE DIE ASSEMBLY Filed July 15, 1959 4 Sheets-Sheet 1 Elm .717 1/5 11 In I" 6125561" M K mi d/J1 0' Sept. 11, 1962 c. M. KOWALSKI PIERCE AND FLANGE DIE ASSEMBLY 4 Sheets-Sheet 2 Filed July 15, 1959 Sept. 11, 1962 c. M. KOWALSKI 7 3,053,210

PIERCE AND FLANGE DIE ASSEMBLY Filed July 15, 1959 4 Sheets-Sheet 5 [21/ FE 1715 F flesh? Kaila/Z261;-

Sept. 11, 1962 c. M. KOWALSKI PIERCE AND FLANGE DIE ASSEMBLY 4 Sheets-Sheet 4 Filed July 15, 1959 [171 15 HIUF ()1 ejierMffou/alJ/i 0' @KA WHH 5 3,053,210 PIERCE AND FLANGE DIE ASSEWLY Chester M. Kowalski, Livonia, Mich., assignor to Lyon Incorporated, Detroit, Mich., a corporation of Delaware Filed July 15, 1959, Ser. No. 827,236 Claims. (Cl. 11342) The present invention relates broadly to the art of metal formation and is more particularly concerned with a new and improved die assembly efiective to sequentially pierce a metal part and form a flange about the pierced opening therein and having among its advantages a complete absence of burrs or sharp surfaces on the formed flange.

The production of automotive wheel covers, to which the instant invention particularly relates although not being so limited, requires as one step the formation of a valve stem opening and an annular flange thereabout radially inwardly of the wheel cover peripheral portion. It has heretofore been the practice to employ for this purpose a tubular piercing and flange forming punch in association with a tubular female die member backed by spring means having a high degree of resistance to compression. Accordingly, subsequent to the piercing step and upon entry of the punch flange forming surface into the mating portion of the die cavity, substantial resistance to flange formation was encountered and the metal forming the flange surrounding the pierced opening was smeared or wiped, with the result that sharp and dangerous burrs were formed on the flange. This condition is naturally a hazard to manufacturing personnel, and burr removal required an additional manufacturing step with associated increased cost.

It is therefore an important aim of the present invention to provide a piercing and flange forming method wherein a shearing action is employed and the metal surrounding the pierced opening is essentially smooth so that during flange formation no wiping action occurs with the production of objectionable burrs.

Another object of this invention lies in the provision of a die assembly for piercing and flange formation, and in which the female die member is held rigid with respect to the advancing punch member during piercing and is moved in the direction of punch movement and away therefrom during flange formation to effectively eliminate sharp surfaces on the formed flange.

A further object of the instant invention is to provide, in association with the described die assembly, a supporting member for a work piece of disc-like configuration and which is pivotally mounted for translatory movement to direct the work piece unto the die assembly during advancement of the punch assembly in contact with the work piece on the supporting member.

A still further object of this invention lies in the provision of a die assembly for piercing and flange forming operations upon a metal part, and which features a punch member having an active end provided with piercing and flange forming surfaces, a die member having a collar member provided with a contoured end and a sleeve member receivable within the collar member and having an end contoured to the end of the collar member to lie flush therewith during the piercing operation and to provide a cutting surface cooperating with the piercing surface on the punch member during said operation, and a support member receiving the opposite end of the sleeve member to restrain the same during piercing and resiliently urged in sliding contact with said end of the sleeve member during advancement of the punch member and subsequent to the piercing operation, to continuously 'move the sleeve member in the direction'of punch travel during flange formation to prevent a wiping of the flange by the punch and the formation of sharp burrs thereon.

Other objects and advantages of the invention will become more apparent during the course of the following description, particularly when taken in connection with the accompanying drawings.

in the drawings, wherein like numerals designate like parts throughout the same:

FIGURE 1 is a fragmentary vertical sectional ViGW,

with parts in elevation, showing a die assembly embodying the concepts of this invention and with the punch member spaced relative to the die member preparatory to the piercing and flange forming operations;

FIGURE 2 is a vertical sectional view of the die assembly with additional details thereof shown, and illustrating the piercing step;

FIGURE 3 is a view similar to FIGURE 2, and showing further advancement of the punch member and lowering of the die member sleeve during flange formation; and

FIGURE 4 is a plan view of the die member of the preceding views.

vThe die apparatus and method of this invention are of especial utility in the provision of valve openings and surrounding flanges located radially inwardly of the periphery of automobile wheel covers, and will accordingly be specifically described in this connection herein. It will be readily apparent, however, to those skilled in the metal working arts that the novel techniques of piercing and flange formation herein disclosed are not restricted to the wheel cover art. As for example, flat metal sheets, metal rims and articles of disc-like configuration can eflectively be processed in accordance with the steps of this method.

Referring now first to FIGURE 1 of the drawings, there is shown an illustrative form of wheel cover 10 having an annular inwardly turned peripheral flange portion 11 connecting with .an annular intermediate dished portion 12, and in which the valve hole and surrounding flange is conventionally provided. The other details of the wheel cover 10 do not bear upon this invention and accordingly are not specifically described, except to note that the annular dished portion 12 may connect with an annular raised portion 13, radially inwardly of which may be a second annular dished portion 14 ultimately connecting with a central portion 15 of generally domeshaped configuration.

To render unnecessary the hand manipulation of the wheel cover 10 for initiation of the piercing step, there is herein provided support means including a shelf portion 16 which accurately tilts or translates the wheel cover 10 to an accurately located position on the die member under action of the punch member, each of which will be described in detail hereinafter. The support means 16 may take the form of a relatively flat table engagea-ble on one side with the peripheral flange 11 of the wheel cover 10 and translatable in a generally clockwise direction by means of a rod member 17 rrounted by a flange 18 and pivotally receiving a shaped bracket 19 rigidly mounted at its opposite ends by die member base 20 through the use of screw means or the like 21. The bracket member 19 is apertured at 22 to receive therethrough bolt means 23 threaded into the support member shelf portion 16 through a rigid nut connection 24 which also provides bottoming means for a yieldable biasing spring means 25 encircling the bolt means 23. As will be described in detail later in connection with the steps of the instant method, the support means 16 with wheel cover 10 thereon are maintained in a substantially level and ready position prior-t0 the piercing step by the stop action provided by abutments of the bolt means 23 against the walls defining the bracket aperture 22, as shown in FIGURE 1. However, when the wheel cover and shelf portion 16 are tipped or translated during contacting advancement of the punch member, the bolt means 23 is generally in an intermediate or spaced relation with respect to the bracket opening 23, as indicated in FIGURES 2 and 3 of the drawings.

The die apparatus of this invention is designated in its entirety in FIGURE 2 by the legend A, and may be seen to comprise a die assembly 2% and punch assembly 26. The movable punch assembly 26 is provided with a head portion 27 supporting one or a pair of spaced upright members 28 carrying at their lower ends a block member 29 having tapered cam surfaces 2% and 2912, which cooperate with structure of the die assembly to lower one portion of said assembly during the flange forming operation.

The head portion or plate 27 of the movable punch assembly 26 additionally supports a mounting block 30 rigidly receiving a punch member 31, shown to be of stepped configuration and having a head portion 32 and a shank or active end portion 33 provided with an axially inclined flange forming surface 34 and an axially inclined piercing or cutting surface 35. The flange forming surface 34 and cutting surface 35 define therebetween a shank segment 33a which is preferably tubular, and as appears in the drawings, the outer diameter thereof is slightly less than the diameter of the upstream shank section 33b. The latter section may or may not be hollow. As also appears, the inclined flange forming surface 34 and piercing or cutting surface 35 are inclined to essentially the same extent and therefore lie generally parallel one with the other.

To provide a resilient cushioning action during piercing and flange formation, to prevent scratching of the wheel cover 10 by the punch 31, and to urge the wheel cover and support means shelf portion 16 tiltably downwardly during punch travel, the punch shank or active end 33 may mount thereabout a cushioning member 36, shown the FIGURE 1 prior to compression as having a generally tubular shape. The cushioning member 36 may have a tapered lower surface 36a which corresponds generally with the inclined cutting face 35 on the punch active end 33. The cushioning member 36 during the steps of the instant process is shown in FIGURES 1, 2 and 3, and the compression thereof will be described specifically hereinafter.

The die assembly 20 of the apparatus A of this invention comprises a base portion 37 apertured at 38 and 39, the former opening 38 receiving the leg member 28 of the punch assembly 26 during the flange forming operation, and the latter opening 39 being in the nature of a chute to direct cut pieces therethrough from the piercing step. The die base portion 37 preferably mounts upon its upper surface a block member 40 to guide the punch assembly upright 28 during its travel.

Also mounted upon the upper surface of the die base 37 is a die supporting member 41, shown in FIGURE 4 to be of general T-shape in plan. The die supporting member 41 may be secured to the die base portion 37 by screw means or the like 42, and the die support 41 has a stepped bore 43 extending partially therethrough and receiving a die collar member 44. The die collar member 44 may be seen to be provided generally centrally of its axial length with a radial flange 45 seated in the stepped bore 43 in the die support 41 and through which may pass screw means or the like 46 to attach the collar member 44 to the die support member 41. Additional attaching means may take the form of horizontally extending screw means or similar devices 47.

It may be noted from the drawings that the upper surface of the collar member flange 45 lies generally flush with the upper surface of the die support member 41, and upwardly therefrom the collar member 44 is provided with an annular neck portion 48. The inner and outer diameters of the neck portion 48 may be seen to be non-concentric, and at the upstream end of said neck portion there is provided an axially inclined or flaring mouth portion 49. As best shown in FIGURE 1, the inclined mouth portion 49 has a relatively wide upper surface 49a against which bears the wheel cover support shelf 16, an arcuate surface 49b which supports the wheel cover annular dished portion 12 during piercing or cutting, a straight or axial portion 49c which cooperates with the punch flange forming surface 34 to turn a portion of the metal in the wheel cover dished portion 12 to provide the flange surrounding the pierced opening, and a downstream upper surface 49d also supporting the wheel cover dished portion during piercing and flange formation.

The die collar 44 slidably receives a die sleeve member or tubular shearing member 50 provided with an arcuately inclined mouth portion 51 having a shearing surface 52. The tubular shearing member 50 has a stepped bore 53 therethrough forming at the upstream end thereof a shoulder 54 which defines generally the extent of axial travel of the punch reduced diameter portion 3312 within the sleeve member '50. In other words the maximum distance from the shoulder 54 outwardly therefrom to the highest point on the arcuately inclined mouth 51 of the sleeve member 50 corresponds generally to the axial length of the punch reduced diameter portion 331:, whereby entry of the punch within the sleeve member is stopped by abutment of the punch flange forming surface 34 against upstream end surface 55 on said sleeve member.

The opposite end of the shearing tube is tapered as at 56 and said tapered end at all times bears against an inclined surface 57 on leg portion 58 connecting with an arm portion 59 of a horizontally slidable generally T- shaped member 60. The member 60 is supported for horizontally slidable movement upon the upper surface of the die base plate 37, and in FIGURES 2 and 3 it will be noted that the arm portion 59 of said member 60 has tapering cam surfaces 60a and 60b formed thereon. The arrangement of parts prior to the flanging operation is shown in FIGURE 2, and at this time the arm portion 59 of the slidable T-shaped member 60 is held rigid by the bar member 29 on the punch assembly depending leg 28, to provide a firm support for the slidable sleeve member 50 during the shearing operation. However, subsequent to shearing and during flange forming the sleeve member 50 slides downwardly along the inclined surface 57 of the T member leg portion 58, by reason of the release of abutting contact between the T member arm portion 59 and the bar portion 29 on the punch assembly leg 28, as shown in FIGURE 3.

To slidably withdraw the T-shaped member 60 during descent of the punch assembly 26, and specifically when the leg portion 28 thereof proceeds vertically downwardly from the position of FIGURE 2 to that of FIGURE 3, the arm portion 59 of the T-shaped member 60 mounts resilient means in the manner of FIGURE 4. At opposite ends of the arm portion 59 there is received a pair of pin means 61 in openings 62 provided in said ann portion. The openings 62 each have a relatively large diameter portion 63 at one end of which there is bottomed spring means 64 encircling the pin means 61 and bottoming at its opposite end against surface 65 formed on the die support 41. It may be noted that the die support member 41 further has a tapered surface 66 under which may slide the similarly shaped surface 57 on the leg portion 58 of the T-shaped member 60. It may now be seen that the spring means 64 resiliently urges the T-shaped member 60 rearwardly or to the right as viewed in FIGURES 2 and 3, slidably lowering the shearing sleeve 50 along its inclined bottom surface 56 on the inclined surface 57 gf the leg portion 58 forming a part of the T-shaped mem- The relative position of the parts of the die apparatus A prior to piercing and flange formation, and the location of the wheel cover 10 with respect thereto, are shown in FIGURE 1. It may be noted therefrom that the adjacent portion of the table support shelf 16 with wheel cover thereon is disposed at a higher elevation than the surface 49a of the die collar member 44. When lowering motion is imparted to the punch assembly 26, the wheel cover annular dished portion 12 is contacted by the annular cushion 36 surrounding the punch shank 33 to tilt or pivot the table support shelf portion 16 in a generally clockwise direction in opposition to the bias of the spring to lower the wheel cover 10 to essentially the position shown in FIGURE 2.

When so lowered, the shelf portion 16 for the wheel cover 10 occupies the position more or less rearwardly of the die collar member 44, and particularly, to the rear of the neck portion 48 thereof. The wheel cover 10 is deposited upon the arcuately inclined mouth portion 49 of the die collar neck portion 48 and closely spaced from the arcuately inclined mouth 51 of the shearing sleeve 56. Essentially simultaneously, the shearing surface on the punch active end 33 penetrates the wheel cover dished portion 12 and effects a rapid and clean shearing action in cooperation with the shearing surface 52 of the sleeve member 50. A round slug 12a is removed therefrom, and this is shown in FIGURE 2 descending through the sleeve member from which it will pass into and through an elongated slot 67 in the leg portion 58 of the T-shaped member 60.

It is to be noted that at this time the sleeve member 50 is firmly supported along its inclined bottom surface 56 upon the similarly shaped surface 57 on the leg portion 58 of the T-shaped member 60. In other words, only a minor amount of movement of the punch assembly upright 28 occurs relative to punch movement, so that as piercing or shearing action occurs the mating surfaces on the arm portion 59 of the member 60 and on the bar portion 29 remain in contacting relation and no movement of the T-shaped member 60 takes place. It is to be further observed that during piercing the annular cushioning member 36 is substantially compressed to a bulbous shape as shown in FIGURE 2, thereby applying a relatively great force area against the wheel dished portion 12 to hold the same firmly against any substantial movement.

After piercing has taken place as described, and upon continued descent of the punch assembly 26, the bar por tion or cam member 29 on the assembly upright 28 rides downwardly on the mating surface of the arm portion 59 of the T-shaped member 6! until said surfaces are essentially completely out of contact. As this sliding contact takes place, the spring means 64 expand to resiliently impart horizontal slidable movement to the T-shaped member 60, whereupon the shearing sleeve 50 slides downwardly upon the inclined surface 57 on the leg 58 of the T-shaped member 60. This horizontal sliding movement of the T-shaped member 60 occurs simultaneously with flange formation, as shown in FIGURE 3. The flange formed is designated therein as 12b, and it will be observed that the flange is formed by cooperating action of the surface 490 on the die collar neck portion 48 and the flange forming surface 34 and relatively greater diameter portion 33b on the punch shank 33. It is important to note that when flange formation is being effected, the shearing sleeve 50 has advanced to a downstream location, as shown in FIGURE 3, and accordingly provides no resistance to flange formation, nor does it in any Way smear or wipe the flange 12b to provide relatively sharp burrs thereon in the manner of the prior art method.

Thus, by providing slidable movement of the shearing tube 50 relative to the die collar 44 subsequent to the shearing or piercing step, and by the provision of punch and die surfaces as illustrated and described, the shearing sleeve 50 has no resistive action during flange formation, and the shaping of the Wheel cover dished portion surrounding the pierced opening is effected only by the die collar surface 49c and the flange forming surface 34 and relatively larger diameter portion 33b on the punch 6 shank 33. The flange 12b is accordingly formed without wiping thereon by the die tube 50, and it now may be seen that burrs or other sharp surfaces are not produced. As a result, injuries to workman are removed from this source, and the necessity of a finishing operation is further removed.

It is of course appreciated that various changes and modifications may be made in the method and apparatus herein disclosed without departing from the novel concepts of the present invention.

I claim as my invention:

1. Apparatus for metal piercing and flange operations upon wheel covers and the like, comprising a punch member having an active end provided with piercing and flange forming surfaces, a die base, a supporting member rigidly mounted on said base and having a collar portion and a sleeve portion slidably received in said collar portion and provided respectively at one end with flange forming and cutting surfaces cooperating with the flange forming and piercing surfaces on the punch member, the opposite end of the sleeve portion being provided with an inclined surface thereon, and a member provided with an inclined surface seating thereon the inclined end of the sleeve portion and being at all times spaced from the active end of the punch member and away from engagement therewith, said member with the inclined surface being essentially stationary during piercing to restrain the sleeve portion during said piercing and being slidable upon the die base to move the sleeve portion inclined surface along the inclined surface of said member with inclined surface, thereby moving the sleeve portion relative to the collar portion and in the direction of punch member travel during flange formation to prevent a wiping action by said sleeve portion and the production of relatively sharp burrs on the flange.

2. Apparatus for metal piercing and flange operations upon wheel covers and the like, comprising a punch member having an active end provided with piercing and flange forming surfaces, a die base, a supporting member rigidly mounted on said base and having a collar portion and a sleeve portion slidably received in said collar portion and provided respectively at one end with flange forming and cutting surfaces cooperating with the flange forming and piercing surfaces on the punch member, a member slidably mounted on the die base and seating the opposite end of the sleeve portion and being at all times spaced from the active end of the punch member and away from engagement therewith and a cam member contacting the slidably mounted member during piercing and maintaining the slidably mounted member essentially stationary during piercing to restrain said sleeve portion against movement, said cam member being movable with the punch member to release the slidably mounted member for slidable movement along the die base, causing the sleeve portion to move within the collar portion and in the direction of punch member travel during flange formation to prevent a wiping action by said sleeve portion and the production of relatively sharp burrs on the flange.

3. Apparatus for metal piercing and flange operations upon wheel covers and the like, comprising a punch member having an active end provided with piercing and flange forming surfaces, a die base, a supporting member rigidly mounted on said base and having a collar portion and a sleeve portion slidably received in said collar portion and provided respectively at one end with flange forming and cutting surfaces cooperating with the flange forming and piercing surfaces on the punch member, a member slidably mounted on the die base and seating the opposite end of the sleeve portion and being at all times spaced from the active end of the punch member and away from engagement therewith, said slidably mounted member being provided with a cam surface, a cam member movable with the punch member and free of cammmg contact with the cam surface on the slidably mounted member during piercing, said cam member and cam surface sliding one upon the other during flange formation and the slidably mounted member sliding upon the die base during said formation, thereby moving the sleeve portion relative to the collar portion and in the direction of punch member travel during flange formation to prevent a wiping action by said sleeve portion and the production of relatively sharp burrs on the flange.

4. Apparatus for metal piercing and flange forming operations, comprising a punch head, a punch member mounted by said punch head and having an active end provided with shearing and flange forming surfaces, a die base member and a die support mounted by said base member and provided with a recess therein, a collar member seated in the die support recess and having an upstanding neck portion providing a flange forming surface cooperating with the punch member flange forming surface, a tubular shearing member received in the collar member and having a cutting surface at one end cooperating With the punch shearing surface, the opposite end of the shearing member being provided with an inclined seating surface, a generally T-shaped member slidable upon the die base member and having an arm portion provided with a cam surface and a leg portion connected to said arm portion and inclined at one end for seating thereon the inclined surface of the shearing member, a cam member connecting with the punch head and free of camming contact with the cam surface on the arm portion of the T-shaped member during shearing, and resilient means urging the cam surface on the arm portion and cam member in sliding camming contact to lower the shearing member by slidable movement of its inclined surface on the leg portion inclined surface to prevent a widening action by the shearing member against the flange during its formation and thereby preventing burrs from being produced thereon.

5. Apparatus for metal piercing and flange forming operations upon wheel covers and the like, comprising a punch member having an active end provided with shearing and flange forming surfaces, a die base, a supporting member rigidly mounted on said base and having a collar portion and a sleeve portion slidably received in said collar portion and provided respectively at one end with flange forming and shearing surfaces cooperating with the flange forming and shearing surfaces on the punch member, a member seating thereon the opposite end of the die sleeve portion and being at all times spaced from the active end of the punch member and away from engagement therewith, said slidable member being essentially stationary during shearing to restrain the sleeve por tion during said shearing and being slidable upon the die base to move the sleeve portion relative to the collar portion and in the direction of punch member travel during flange formation to prevent a wiping action by said sleeve portion with the production of relatively sharp burrs on the flange, and support means including a bracket portion connecting with the die base and a shelf portion movably connected to said bracket portion and having yieldable biasing means acting on said shelf portion for supporting the wheel cover thereon for translatory movement from a generally horizontal position at which the shelf portion and the cover are supported above the die member collar portion and through a substantially arcuate path at which the wheel cover is deposited on said collar portion and spaced above the sleeve portion.

References Cited in the file of this patent UNITED STATES PATENTS 155,110 Robinson Sept. 15, 1874 2,230,043 Moran Jan. 28, 1941 2,554,916 Miller May 29, 1951 2,878,767 Lyon Mar. 24, 1959 2,887,157 Rehdorf May 19, 1959

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