US3834212A

US3834212A - Apparatus for forming metal wheels

Info

Publication number: US3834212A
Application number: US00425976A
Authority: US
Inventors: R Roper
Original assignee: Wallance Expanding Machines Inc
Current assignee: WALLACE ACQUISITION Corp N/K/A WALLACE EXPANDING MACHINES Inc; Wallance Expanding Machines Inc
Priority date: 1972-12-11
Filing date: 1973-12-19
Publication date: 1974-09-10
Anticipated expiration: 1991-09-10

Abstract

A method and apparatus for forming metal wheel assemblies having a rim and attached spider. A pair of outer dies complementary to the final radial form of the wheel rim are moved together to enclose an annular metal workpiece. A pair of opposed conical dies are then moved interiorly of the outer dies and annular workpiece. Each conical die has an annular stuffing ledge which contacts the edge of the workpiece. Force is then exerted against the workpiece edges so as to plastically regenerate the workpiece between the conical dies and outer dies; thus, providing thickening of the material in desired areas. A spider extending across the workpiece is axially loaded with the conical dies causing plastic deformation of the spider. A center rod mounted to and projecting from one of the conical dies is concentric with the conical dies and extends through the spider as the spider plastically deforms therearound. A groove formed in one of the conical dies forms a seating ridge in the spider which is defined by a plane perpendicular to the longitudinal axis of the wheel rim. A plurality of seating bosses are formed into the spider by the conical dies.

Description

[ Sept. 10, 1974 APPARATUS FOR FORMING METAL WHEELS [75] lnventor: Ralph E. Roper, Indianapolis, Ind.

[73] Assignee: Wallance Expanding Machines, Inc., Indianapolis, Ind.

221 Filed: Dec.19,1973

21 Appl. No.: 425,976

Related US. Application Data [60] Continuation-impart of Ser. No. 314,121, Dec, 11, 1972, abandoned, which is a division of Ser. No. 144,155, May 17, 1971, Pat. No. 3,729,795.

Primary Examiner-Charles W. Lanham Assistant Examiner-V. A. Dipalma Attorney, Agent, or FirmWoodward, Weikart, Emhardt & Naughton [5 7] ABSTRACT A method and apparatus for forming metal wheel assemblies having a rim and attached spider. A pair of outer dies complementary to the final radial form of the wheel rim are moved together to enclose an annular metal workpiece. A pair of opposed conical dies are then moved interiorly of the outer dies and annular workpiece. Each conical die has an annular stuffing ledge which contacts the edge of the workpiece. Force is then exerted against the workpiece edges so as to plastically regenerate the workpiece between the conical dies and outer dies; thus, providing thickening of the material in desired areas. A spider extending across the workpiece is axially loaded with the conical dies causing plastic deformation of the spider. A center rod mounted to and projecting from one of the conical dies'is concentric with the conical dies and extends through the spider as the spider plastically deforms therearound. A groove formed in one of the conical dies forms a seating ridge in the spider which is defined by a plane perpendicular to the longitudinal axis of the wheel rim. A plurality of seating bosses are formed into the spider by the conical dies.

11 Claims, 11 Drawing Figures PAIENTEBSEP 1 0191+ v m1 "1' or 9' Fig.1

PAIENTED SE? 1 01974 sum not 9 w 75 A, I

Fig.5

mxmw PATENIEDSEPIOIHH Y V 3.834.212

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APPARATUS FOR FORMING METAL mars CROSS REFERENCE TO RELATED APPLICATION This is a continuation-in-part of my prior application Ser. No. 314,121, filed Dec. 1 l, 1972, now abandoned, which is a divisional of my prior application Ser. No. 144,155, filed May 17, 1971, now US. Pat. No. 3,729,795.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to methods and devices for forming wheels.

2. Description of the Prior Art In my US. Pat. No. 3,263,477 entitled Apparatus for Forming Metallic Ring Members", there is disclosed an apparatus for forming a wheel rim by use of dies employing my stuffing ledge technique. The stuffing technique is also disclosed in my US. Pat. No. 3,584,366 entitled Process for Manufacture of Shadow Mask Frames. Disclosed herein is an apparatus for forming a wheel rim which has a spider web for mounting the rim to a rotatable carrier. The stufiing ledge technique is utilized in the subject apparatus. My US. Pat. No. 3,729,795 entitled Method for Fonning Metal Wheels" discloses the method accomplished by the subject apparatus.

Several US. Patents have issued for forming wheel rims. For example, the following US. Patents: US. Pat. No. 2,586,029 issued to Greenshields; US. Pat. No. 2,649,886 issued to Palmer; U.S. Pat. No. 2,826,161 issued to Palmer; and US. Pat. No. 3,509,755 issued to Bulgrin. All disclose devices for forming wheel rims. A more recent US. Pat. No. 3,530,717 issued to Gregg discloses a machine for rounding a wheel having a spider web attached to the wheel rim. The Gregg device has rounding dies to engage the rim periphery, which is preferably fonned oversize when the wheel is assembled for bringing the rim into axial and radial alignment. When the rim is held in its true position by the rounding dies, a machining or formingoperation is effected upon a locating opening in the spider web so that the rim will be true with respect to its axis of rotation as defined by this locating opening. It can be appreciated that when radially loading an oversized rim, the tendency will be for the spider web to spring back. Thus, the prior art devices, as disclosed on line 72 of page 6 of the Gregg patent, provide for allowance to reduce the springback. Although the center opening is located centrally of the rim, the desired mounting arrangement of the wheel will not be achieved in the event that the spider web is not exactly parallel with the periphery of the rim. It is therefore desirable to severely minimize the springback and to ensure that the mounting portion of the spider web is exactly perpendicular to the longitudinal axis of the rim. Disclosed herein is a method and apparatus for achieving this objective. The rim is axially loaded in lieu of being radially loaded so as to plastically deform the rim. Simultaneously with the plastic deformation of the rim, the spider is also plastically deformed so as to reclassify or coin the spindle mounting hole of the spider into near perfect relation with the wheel axis. As a result of the homogeneous rearrangement of the wheel rim and spider assembly, the dimensional tolerance of the finished wheel is better than the dimensional tolerance experienced in the utilization of the prior art machines. Also by correct spacing of the dies, the thickness of the rim may be controlled throughout the rim length. For ex ample, it may be desirable to increase the thickness in A high stress areas while decreasing the thickness in low stress areas. This thickness control will allow the use of relative thinner sheet material. The resulting material savings will provide a very significant cost savings.

SUMMARY OF THE INVENTION One embodiment of the present invention is an apparatus comprising a pair of coaxial generally conical dies pointing toward one another, first means for moving said dies together whereby said dies may be seated within the opposite ends of an annular workpiece, having a spider in engagement with the inner surface of the workpiece, a plurality of outer dies arranged in a pattern coaxial with said generally conical dies, means for moving said outer dies together wherein the inner surface of said outer dies engage the outer surface of said workpiece and cooperate with said generally conical dies to form the workpiece, said generally conical dies being provided with mutually facing stuffing ledges which cooperate with said outer dies to stuff the material of the workpiece between said outer dies and said generally conical dies wherein the improvement comprises: said generally conical dies have mutually facing surfaces with one of said facing surfaces having a rod projecting therefrom centrally of said stuffing ledges and concentric with said conical dies toward the other of said facing surfaces, said rod being positioned to extend axially through said spider; and, said stuffing ledges being spaced apart a distance less than the axial length of said workpiece and said conical dies being spaced from said outer dies a distance greater than the thickness of said workpiece when said outer dies and said conical dies are closed.

An object of the present invention is to provide a new and improved apparatus for forming a wheel.

It is also an object of the present invention to provide an apparatus for establishing a spindle hole of a wheel which is centrally positioned.

It is a further object of the present invention to provide an apparatus for plastically deforming a wheel so as to establish a true mounting plane perpendicular to the axis of rotation.

In addition, it is an object of the present invention to provide an apparatus for forming a wheel having accurately positioned mounting bosses.

Related objects and advantages of the present invention will be apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary vertical section through one embodiment of a wheel assembly forming apparatus embodying the present invention with the dies shown in the completely open position.

FIG. 2 is the same view as FIG. 1 only showing the outer dies in the closed position.

FIG. 3 is the same view as FIG. 2 only showing the conical dies in the partially closed position.

FIG. 4 is the same view as FIG. 3 only showing the conical dies in the completely closed position.

FIG. 5 is a cross-sectional view taken along the line 55 of FIG. 4 and viewed in the direction of the arrows.

FIG. 6 is an enlarged fragmentary view of the dies.

FIG. 7 is the same view as FIG. 6 only with less detail and with an alternate center pilot rod shown.

FIG. 8 is a schematic representation of a second embodiment of a wheel assembly forming apparatus embodying the present invention.

FIG. 9 is a fragmentary vertical section through the wheel assembly forming apparatus depicted in FIG. 8 with the dies shown in the completely open position.

FIG. 10 is the same view as FIG. 9 only showing the outer dies in the closed position.

FIG. 11 is the same view as FIG. 10 only showing the conical dies in the closed position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawing and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby illustrated, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

Referring now more particularly to FIGS. 1 through 4, there is illustrated the first embodiment of the apparatus incorporating the present invention. Apparatus has a pair of horizontally opposed coaxial conical dies 21 and 22 movably mounted to engage and form a wheel 25 having a rim 26 with edges 27 and a spider 28 integrally joined to and extending across the rim. The center of the spider is provided with opening 29 with a plurality of lug receiving bosses 30 positioned equidistant around hole 29. A wheel such as wheel 25 may be found on various vehicles such as automobiles and trucks. A pair of outer dies 23 and 24 are arranged in a pattern coaxial with the generally conical dies and may be moved to engage the outer surface of the rim so as to cooperate with the conical dies 21 and 22 to final form the wheel. The top outer die 23 is vertically movable to and from the bottom die 24 which is mounted to a lower die retainer 34 fixedly secured to a support wall 33. Bottom die 24 does not move since retainer 34 and support wall 33 are fixedly secured to the bottom wall 31 (FIG. 5) of the apparatus. A plurality of upstanding members 32 secure wall 33 and retainer 34 to wall 31.

The apparatus is utilized to final form the wheel after the spider has been attached to the rim. A variety of methods, such as welding or riveting, may be utilized to attach the spider to the rim. Subsequent to the attaching of the spider to the rim, the wheel is inserted by a loading device to be described later in this specification so as to rest upon the bottom outer die 24 as shown in FIG. 1. The top outer die 23 is then moved vertically downward to engage the wheel as shown in FIG. 2. Next, the pair of conical dies 21 and 22 are moved toward the wheel in order that the stuffing ledges 52 and 53 (FIG. 6) of each die 21 and 22 will engage the edges 27 of the rim 26 as shown in FIG. 3.

Ledges

52 and 53 extend around the dies 21 and 22 and contact the rim edges completely around the circumference of the wheel. The mutually facing stuffing

ledges

52 and 53 cooperate with the outer dies 23 and 24 to stuff the maten'al of the rim between the outer dies and the generally conical dies as the conical dies are moved to the most inward position as shown in FIG. 4. Thus, the assembled wheel with spider is an annular workpiece which is final formed to the desired shape and configuration by the apparatus disclosed herein.

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 4 viewed in the direction of the arrows. Referring now to FIG. 5, a hydraulic cylinder motor 37 is mounted to the top wall 38 which is secured to the vertical walls of the apparatus. The piston rod 39 of the hydraulic cylinder motor is movable vertically therefrom and has a bottom end secured to the upper die retainer 35 which carries the top outer die 23. Retainer 35 is vertically movable within a pair of guides 36 positioned on either side of the retainer. Thus, by activation by hydraulic cylinder motor 37, the upper retainer 35 and top die 23 may be moved to and from wheel 25. A number of different structures may be utilized to mount the vertically movable retainer 35. For example, the retainer may have ribs which project into grooves formed in guides 36 or guides 36 may have ribs which project into complementary sized grooves provided in the retainer.

After the wheel has been formed by apparatus 20, the conical dies are moved apart and the top outer die 23 is moved upwardly. In certain instances, the final formed wheel may become lodged in the top outer die. Thus, a spring loaded rod 66 is slidable within hole 67 of die 23 and will move downwardly under the force of a spring means (not shown) thereby engaging the wheel and forcing the wheel from the die. Likewise, in certain instances, the wheel may become lodged with respect to the bottom outer die 24. Thus, a rod 44 is provided which will project from hole 45 of die 24 so as to free the final formed wheel from the bottom outer die 24. Rod 44 is moved upwardly by activating lever 48 operated by unloader 56. Lever 48 is pivotally mounted to a bracket 49 secured to wall 33. A spring 54 normally urges end 68 of lever 48 in the most downward position. End 68 receives a rod 46 slidable in hole 47 of retainer 34. Rods 44 and 46 are aligned and are in contact. A third rod 55 is slidable in retainer 34 and abuts the opposite end of lever 48. The top end of rod 55 projects through the top of retainer 34 and is depressed by pad 64 when unloader 56 pivots in the direction of arrow 59. Downward movement of rod 55 forces lever 48 to pivot thereby moving rods 46 and 44 upwardly and freeing the final formed wheel from the bottom die. A pair of contact pads 42 and 43 are provided on

retainers

34 and 35 with pads 43 being provided with holes to receive rod 55.

Loader 62 has an arm which may be pivoted in the direction of arrow 63 so as to load the assembled wheel into the apparatus. The unloader 56 is similar in design and construction to loader 62 and thus the following description of unloader 56 will apply equally to loader 62. A hydraulic cylinder motor is mounted to bracket secured to member 32 of the apparatus. The piston rod 61 of hydraulic cylinder motor 60 is pivotally connected to an arm 58 which in turn is pivotally mounted to the apparatus. A gripping device 57 is provided at the end of the arm 58 to engage the final formed wheels when the arm is pivoted in the direction of arrow 59 by extending rod 61. Thus, the loader and unloader may be sequenced with the movement of the dies thereby providing for completely automatic operation.

Dies 21 and 22 (FIG. 4) are secured respectively to press

rams

50 and 75 by

fastening devices

69 and 70. The fastening devices are threaded bolts with the head 71 of fastener 70 projecting from die 22 and into hole 73 (FIG. 6) of die 21 when the dies are in the completely closed position. The head of fastener 69 is recessed so as to allow head 71 to enter hole 73. Dies 21 and 22 have mutually facing surfaces which are complementary in size and configuration. Head 71 projects through the mutually facing surfaces and is positioned centrally with respect to stuffing

ledges

52 and 53 being concentric therewith. In view of the concentricity of the stuffing ledges and head 71, the opening 29 of spider web 28 will be positioned centrally and concentrically with respect to the rim. In the event that opening 29 is smaller than head 71, then a portion of the spider surrounding the head will be pushed to the left as viewed in FIG. 4 thereby forming a flanged portion 74 (FIG. 6). The chamfered portion 72 of fastener 70 when inserted through the spider will form a slight countersink around the center spider opening.

Other wheel designs have spider spindle holes without a flange. FIG. 7 shows such a wheel which has a flat portion 74' around the spindle hole. The pilot rod 70' of desired finished diameter is entered through a slightly oversized pre-pierced hole in the spider. Shoulder 72' of rod70' coins a depression in the spider around the pilot 71' extended through the hole in the spider thereby packing the metal around pilot 71' and establishing an accurate hole size concentric with the wheel rim axis.

Automotive wheel assemblies typically have a plurality of lug receiving bosses spaced equidistant around the center spider opening. These bosses receive the lugs fixedly projecting from the wheel of the vehicle wheel hub with hexagonally shaped nuts being provided to secure the spider to the lugs. The mounting bosses of spider 28 are located at position 89 (FIG. 6) being spaced equidistant around opening 29. A plurality of seat forming bosses 89 are provided on die 22 being spaced equidistant around axis 84. Immediately outward and adjacent bosses 89, the spider is depressed forming a mounting ridge 92 which extends around opening 29. Ridge 92 is formed by protrusion 81 of die 21 being received in groove 80 of die 22. The innermost portion or vertex of groove 80 defines a plane 83 which is perpendicular to the longitudinal axis 84 extending centrally through dies 21 and 22 and wheel 25. Plane 83 is parallel with

ledges

52 and 53. Surface 82 of ridge 92 adjacent to the vertex of groove 80 forms a mounting surface parallel with plane 83 which abuts against the exterior surface of the hub receiving wheel 25. Bosses 89 each have a surface 90 nearest die 21 defining the plane 91 parallel with plane 83, perpendicular to axis 84 and parallel to stuffing

ledges

52 and 53.

Dies 21 and 22 are horizontally movable by a pair of hydraulic cylinder motors. Press rams 50 and 75 (FIG. 1) have cylindrical rod portions which are integrally joined to piston heads 76. Hydraulic pressure is applied to the back surface (not shown) of piston heads 76 to move the cylindrical portions inward. By placing a negative hydraulic pressure on the back surface of the piston, the rod portions may be moved outwardly. Each rod portion is surrounded by a locking ring. Locking ring 40 surrounds the cylindrical rod portion attached to die 21 whereas locking ring 41 surrounds the cylindrical rod portion attached to die 22. Each locking ring is horizontally slidable being mounted to guides 93 which are similar to guides 36 previously described and shown in FIG. 5. Locking ring 41 will now be described it being understood that a similar description applies to locking ring 40. Locking ring 41 has a cylindrical ring 94 fixedly attached thereto by fastening devices 96. The innermost side 95 of ring 94 is tapered so as to provide a camming surface when contacting tapered sides 97 of

retainers

34 and 35. Piston 76 is moved to the left as viewed in FIGS. 1 through 5, by slide 41 contacting ring 100 in the direction of arrow 98 by means of two pistons not shown until the tapered side 95 of ring 94 contacts tapered side 97 of the closed retainer 35 and retainer 34 thereby together with locking ring 40 cooperatively locking dies 23 and 24 together. Ring 100 fits within portion 101 and contacts surface 102. Pressure is now applied to piston head 76 which completes inward travel of dies 21 and 22 thus forming the part 25. The pressure is released on piston head 76 and slide 41 is retracted in a direction opposite to arrow 98. Slide 41 contacts surface 99 and moves piston 76 at the same time. Piston moves in a similar manner. Die 23 may then be moved upwardly. The locking rings lock dies 23 and 24 together when dies 23 and 24 close but before dies 21 and 22 engage the wheel.

Dies 21 and 22 are arranged so as to provide for the regeneration and plasticization of the wheel rim and spider assembly. The distance (FIG. 4) between the stuffing

ledges

52 and 53 in the completely closed position is less than the axial length of the workpiece which of course is the assembled wheel prior to final forming. Thus, after the annular metal workpiece is enclosed by dies 23 and 24, the rim edges of the workpiece are contacted by the annular stufiing ledges and columnar force is then exerted axially against the rim edges with dies 21 and 22 to cause plastic deformation of the workpiece. Eventually, the mutually facing surfaces of dies 21 and 22 will contact the spider and axiallyload the spider to cause plastic deformation thereof. The plastic deformation of the spider occurs subsequent to the contacting of the rim edges by the stuffing ledges but occurs during the plastic deformation of the rim. The distance between the stuffing ledges 85 is shown in FIG. 4 with the dies in the completely closed position whereas the axial length of the workpiece prior to deformation is shown as distance 86 in FIG. 3. In addition, the rim thickness 87 (FIG. 3) of the rim prior to final forming is less than the distance 88 (FIG. 4) between the outer and inner dies when the dies are in the completely closed position. As a result, the axial length of the wheel is decreased with the thickness of the rim being increased during the final forming operation. The plasticization of the rim and spider prevents the springback problem discussed in the section entitled Description of the Prior Art. In addition, it is the stuffing action that creates the extreme close tolerance for radial perfection. The application of the stuffing ledge likewise perfects the lateral tolerance for the mounting flanges of the tire. The work for regenerating the rim and spider is accomplished solely by the driving force of dies 21 and 22 with the outer dies 23 and 24 providing a fixed precision retainer during the forming operation.

The method of forming the wheel rim through the utilization of apparatus provides for enclosing the continuous annular metal workpiece with the pair of outer dies complementary to the final radial form of the rim. As previously described, the rim edges are contacted with the annular stufiing ledges of the conical dies and then columnar force is exerted axially against the edges with the inner dies to cause plastic deformation of the workpiece. Eventually, the mutually facing surfaces of the conical dies axially load the spider to cause plastic deformation of the spider in desired local areas subsequent to the contacting step but during the plastic deformation of the rim. Due to the plasticization of the annular workpiece and spider and the cooperative extruding or coining around the center spider opening and the coining of the mounting pads, several important results occur. For example, the two outside edges of the rim are established parallel; the radial runout in the tire fit area is regenerated and burnished creating a small tolerance at this area, and the lateral runout measured in the wheel flange area where the tire abuts the side wall of the rim is compressed and formed against the outer die forming a highly compressed condition and retaining a small runout tolerance.

A center rod or head 71 is held centrally with respect to the stuffing ledges so as to project axially through the spider during the axial loading step defining a hole therethrough as the spider plastically deforms and repacks around the spider. As previously mentioned, the outer dies are held apart from the conical dies a distance greater than the thickness of the workpiece when the dies are in the completely closed position. Likewise, the stuffing ledges are held apart a distance less than the axial length of the workpiece when the dies are in the completely closed position. A ridge is formed around the center hole receiving head 71 during the plastic deformation of the spider so as to define a seating plane 83 perpendicular to the longitudinal axis 84 and parallel to the rim edges. The stepped and tapered cross section of the rim as shown in FIG. 1 provides for the burnishing of the rim edges when the conical dies are moved inwardly. The parallel mounting pads are formed into the spider equidistant from the outer dies during the plastic deformation of the spider with the pads being perpendicular to the longitudinal axis of the rim. Prior to inserting the assembled wheel into the apparatus 20, a continuous annular metal rim is formed with a spider being secured interiorly to and radially across the rim.

FIGS. 8 through 11 show a second embodiment of the wheel assembly forming apparatus. Apparatus 130, shown in the exploded fragmented view of FIG. 8, has a pair of vertically opposed coaxial conical dies 131 and 132 movably mounted to engage and form wheel 25. A pair of outer dies 133 and 134 are arranged in a pattern coaxial with the generally conical dies 131 and 132 and may be moved to engage the outer surface of the rim so as to cooperate with the conical dies 131 and 132 to final form the wheel. Apparatus 130 is similar to apparatus 20 with the exception that the conical dies 13] and 132 of apparatus 130 are vertically movable together as contrasted to the horizontally movable conical dies 21 and 22 of apparatus 20. Likewise, outer dies 133 and 134 are horizontally moved together as contrasted to outer dies 23 and 24 which are movable vertically together in apparatus 20.

Conical die 131 (FIG. 9) is stationary and is mounted atop riser 135 secured to lower shoe 136. The upper conical die 132 is mounted by support 137 to the upper shoe 138 movable downward by press 139. Dies 131 and 132 are configured identical to dies 21 and 22 for final forming wheel 25 which includes a rim and spider secured together. Thus, conical dies 131 and 132 are provided with stuffing ledges identical to the stuffing ledges described for dies 21 and 22.

Outer dies 133 and 134 are respectively mounted to

slides

140 and 141 each having cam surfaces 142 engageable by cam surfaces 143 of upper pad 144. Outer dies 133 and 134 are configured identical to outer dies 23 and 24 (FIG. 1) for holding wheel assembly 25 during the final forming thereof. The outer dies and conical dies are shown in the completely open position in FIG. 9. Downward movement of upper pad 144 in the direction of arrow 145 causes slides 140 and 141 to move radially inward respectively in the direction of

arrows

146 and 147 thereby engaging the assembled wheel 25 as shown in FIG. 10. A plurality of locator bars 148 are fixedly mounted to the lower pad 146 with each locator bar having an inner end 149 for locating and holding assembled wheel 25. The inner end 149 of each locator bar 148 is spring loaded by springs 150 so as to project radially inward to releasably hold the annular workpiece as the outer dies 133 and 134 move together eventually securing the annular workpiece.

Outer dies 133 and 134 are shown in FIG. 10 in the closed position and are locked in place by the dwell of the cams mounted to upper pad 144. The upper die 132 is then forced downwardly as shown in FIG. 11 so as to bottom out on wheel 25 and together with dies 131, 133 and 134 to final form and plasticize the assembled wheel.

The upper pad 144 is spaced apart by distance 145 (FIG. 11) from the lower pad 146 thereby allowing the assembled wheel and the outer dies 133 and 134 to vertically float to the correct position about dies 131 and 132. Pad 146 is supported by pneumatic cylinders 147 (FIG. 11) mounted atop shoe 136 allowing dies 133 and 134 to float vertically. Likewise, pneumatic cylinders 151 are mounted atop pad 144 supporting shoe 138.

Cylinders

147 and 151 are fully extended with dies 131 and 132 apart; however,

cylinders

147 and 151 contract as die 132 forces wheel 25 against die 131 thereby allowing dies 133 and 134 to seek the appropriate vertical position to hold wheel 25.

Wheel assemblies 25 are moved towards apparatus 130 by input conveyor 149 and are moved outward from the apparatus by exit conveyor 150. A suitable device is provided for orienting the assembled wheels and for lubricating and inserting the wheels into apparatus 130. Likewise, a suitable device is provided for removing the final formed assembled wheels from the apparatus. The second embodiment nt of the apparatus shown in FIGS. 8 through 11 is particularly advantageous over the first embodiment since the axis of the wheel is allowed to remain vertical as delivered from a previous welding operation prior to the final sizing operation provided by apparatus 130. Excellent results have been obtained by utilizing a one thousand ton hydraulic press for moving the conical dies and outer dies of apparatus 130 together.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. The two embodiments of the apparatus are different in that in one embodiment the conical dies move vertical whereas in the other embodiment the conical dies move horizontal. In both embodiments, the stuffing ledges are spaced apart a distance less than the axial length of the workpiece with the conical dies spaced from the outer dies a distance greater than the thickness of the workpiece when the conical dies and the outer dies are closed.

The invention claimed is:

1. A forming apparatus comprising a pair of coaxial generally conical dies pointing toward one another, first means for moving said dies together whereby said dies may be seated within the opposite ends of an annular workpiece having a spider in engagement with the inner surface of the workpiece, a plurality of outer dies arranged in a pattern coaxial with said generally conical dies, means for moving said outer dies together wherein the inner surface of said outer dies engage the outer surface of said workpiece and cooperate with said generally conical dies to form the workpiece, said generally conical dies being provided with mutually facing stuffing ledges which cooperate with said outer dies to stuff the material of the workpiece between said outer dies and said generally conical dies wherein the improvement comprises:

said generally conical dies having mutually facing surfaces with one of said facing surfaces having a rod projecting therefrom centrally of said stuffing ledges and concentric with said conical dies toward the other of said facing surfaces, said rod being positioned to extend axially through said spider; and,

said stuffing ledges being spaced apart a distance less than the axial length of said workpiece and said conical dies being spaced from said outer dies a distance greater than the thickness of said workpiece when said outer dies and said conical dies are closed.

2. The apparatus of claim 1 wherein:

one of said facing surfaces has a plurality of seat forming bosses spaced equidistant around the longitudinal axis of said conical dies with the surfaces of said bosses nearest the other of said facing surfaces defining a plane perpendicular to said axis and parallel with said stufling ledges 3. The apparatus of claim 2 wherein:

said die with said forming bosses has a groove formed therein outwardly of and adjacent to said forming bosses, said groove has a vertex defining a second plane perpendicular to said axis, said rod has a decreasing diameter at the location where said rod projects through said mutually facing surfaces.

4. A forming apparatus comprising:

a pair of coaxial generally conical dies pointing toward one another, first means for moving said dies together whereby said dies may be seated within the opposite ends of an annular workpiece having a spider in engagement with the inner surface of the workpiece, a plurality of outer dies arranged in a pattern coaxial with said generally conical dies, means for moving said outer dies together wherein the inner surface of said outer dies engage the outer surface of said workpiece and cooperate with said generally conical dies to form the workpiece, said generally conical dies being provided with mutually facing stuffing ledges which cooperate with said outer dies to stuff the material of the workpiece between said outer dies and said generally conical dies wherein the improvement comprises:

one of said facing surfaces has a plurality of seat fonning bosses spaced equidistant around the longitudinal axis of said conical dies with the surfaces of said bosses nearest the other of said facing surfaces defining a plane perpendicular to said axis and parallel with said stuffing ledges.

5. The apparatus of claim 4 wherein:

one of said facing surfaces has a groove formed therein around the longitudinal axis of the conical dies with the vertex of said groove defining a plane perpendicular to said axis and parallel to said stuffing ledges.

6. The apparatus of claim 5 additionally comprising:

inserting means operable to insert said workpiece onto one of said outer dies; and,

removal means operable to remove said workpiece from said one outer die.

7. The apparatus of claim 6 additionally comprising:

first and second carriers horizontally movable by said first means, each of said carriers having one of said conical dies fixedly mounted thereto;

locking cams movable with said carriers engaging and locking said outer dies together when said outer dies are closed and before said conical dies are engaged; and,

a center rod threadedly securing one of said conical dies to one of said carriers, said rod being concentric with respect to the horizontally extending conical dies and having a tapered head received by the other of said outer dies when said dies are closed.

8. The apparatus of claim 7 wherein:

said one outer die is stationary and the other of said outer dies is movable, said one outer die has means operable by said removal means to dislodge said workpiece from said one outer die.

9. The apparatus of claim 4 wherein:

said conical dies include a stationary bottom punch and an upper punch vertically movable downward toward said lower punch; and,

said outer dies are horizontally movable together to hold said annular workpiece formed by said bottom punch and said upper punch.

10. The apparatus of claim 9 and further comprising:

a plurality of locator bars mounted horizontally in said outer dies and being spring biased radially inward to releasably hold and locate said annular workpiece as said outer dies move together.

11. The apparatus of claim 10 and further comprisa lower pad having said outer dies mounted thereon and surrounding said lower punch; and,

supporting means having said lower pad mounted thereon and being operable to normally position said outer dies above said lower punch for holding said annular workpiece above said lower punch but being yieldable to lower said outer dies positioning said annular workpiece on said lower punch as downward pressure is applied to said lower pad.

Claims

1. A forming apparatus comprising a pair of coaxial generally conical dies pointing toward one another, first means for moving said dies together whereby said dies may be seated within the opposite ends of an annular workpiece having a spider in engagement with the inner surface of the workpiece, a plurality of outer dies arranged in a pattern coaxial with said generally conical dies, means for moving said outer dies together wherein the inner surface of said outer dies engage the outer surface of said workpiece and cooperate with said generally conical dies to form the workpiece, said generally conical dies being provided with mutually facing stuffing ledges which cooperate with said outer dies to stuff the material of the workpiece between said outer dies and said generally conical dies wherein the improvement comprises: said generally conical dies having mutually facing surfaces with one of said facing surfaces having a rod projecting therefrom centrally of said stuffing ledges and concentric with said conical dies toward the other of said facing surfaces, said rod being positioned to extend axially through said spider; and, said stuffing ledges being spaced apart a distance less than the axial length of said workpiece and said conical dies being spaced from said outer dies a distance greater than the thickness of said workpiece when said outer dies and said conical dies are closed.

2. The apparatus of claim 1 wherein: one of said facing surfaces has a plurality of seat forming bosses spaced equidistant around the longitudinal axis of said conical dies with the surfaces of said bosses nearest the other of said facing surfaces defining a plane perpendicular to said axis and parallel with sAid stuffing ledges.

3. The apparatus of claim 2 wherein: said die with said forming bosses has a groove formed therein outwardly of and adjacent to said forming bosses, said groove has a vertex defining a second plane perpendicular to said axis, said rod has a decreasing diameter at the location where said rod projects through said mutually facing surfaces.

4. A forming apparatus comprising: a pair of coaxial generally conical dies pointing toward one another, first means for moving said dies together whereby said dies may be seated within the opposite ends of an annular workpiece having a spider in engagement with the inner surface of the workpiece, a plurality of outer dies arranged in a pattern coaxial with said generally conical dies, means for moving said outer dies together wherein the inner surface of said outer dies engage the outer surface of said workpiece and cooperate with said generally conical dies to form the workpiece, said generally conical dies being provided with mutually facing stuffing ledges which cooperate with said outer dies to stuff the material of the workpiece between said outer dies and said generally conical dies wherein the improvement comprises: one of said facing surfaces has a plurality of seat forming bosses spaced equidistant around the longitudinal axis of said conical dies with the surfaces of said bosses nearest the other of said facing surfaces defining a plane perpendicular to said axis and parallel with said stuffing ledges.

5. The apparatus of claim 4 wherein: one of said facing surfaces has a groove formed therein around the longitudinal axis of the conical dies with the vertex of said groove defining a plane perpendicular to said axis and parallel to said stuffing ledges.

6. The apparatus of claim 5 additionally comprising: inserting means operable to insert said workpiece onto one of said outer dies; and, removal means operable to remove said workpiece from said one outer die.

7. The apparatus of claim 6 additionally comprising: first and second carriers horizontally movable by said first means, each of said carriers having one of said conical dies fixedly mounted thereto; locking cams movable with said carriers engaging and locking said outer dies together when said outer dies are closed and before said conical dies are engaged; and, a center rod threadedly securing one of said conical dies to one of said carriers, said rod being concentric with respect to the horizontally extending conical dies and having a tapered head received by the other of said outer dies when said dies are closed.

8. The apparatus of claim 7 wherein: said one outer die is stationary and the other of said outer dies is movable, said one outer die has means operable by said removal means to dislodge said workpiece from said one outer die.

9. The apparatus of claim 4 wherein: said conical dies include a stationary bottom punch and an upper punch vertically movable downward toward said lower punch; and, said outer dies are horizontally movable together to hold said annular workpiece formed by said bottom punch and said upper punch.

10. The apparatus of claim 9 and further comprising: a plurality of locator bars mounted horizontally in said outer dies and being spring biased radially inward to releasably hold and locate said annular workpiece as said outer dies move together.

11. The apparatus of claim 10 and further comprising: a lower pad having said outer dies mounted thereon and surrounding said lower punch; and, supporting means having said lower pad mounted thereon and being operable to normally position said outer dies above said lower punch for holding said annular workpiece above said lower punch but being yieldable to lower said outer dies positioning said annular workpiece on said lower punch as downward pressure is applied to said lower pad.