US2993458A - Method of and means for making wheel covers - Google Patents

Description

July 25, 1961 G. A. LYON 2,993,458

METHOD OF AND MEANS FOR MAKING WHEEL COVERS Filed Dec. 7, 1956 2 Sheets-Sheet 1 F: qf July 25, 1961 LYON 2,993,458

METHOD OF AND MEANS FOR MAKING WHEEL COVERS 5 45 Eg.7 A l 44 I United States Patent 2,993,458 METHOD OF AND MEANS FOR MAKING WHEEL COVERS George Albert Lyon, 13881 W. Chicago Blvd., Detroit 28, Mich. Filed Dec. 7, 1956, Ser. No. 626,938 7 Claims. (Cl. 113116) The present invention relates to improvements in the making of wheel covers for disposition at the outer sides of vehicle wheels, and more particularly to the making of wheel covers from thin cold workable sheet metal and equipped with self-retaining spring fingers integrally in one piece therewith.

An important problem confronting the maker of sheet metal wheel covers provided with marginal cover retaining spring fingers is to so construct the cover economically by mass production methods as to afford low production costs and yet have the cover equipped with concealed retaining finger structure. In die pressing or drawing the metal blank to provide the cover, the retaining finger structure must initially be located in an exposed peripheral relation about the perimeter of the blank. According to one desirable and highly practical commercial method of ultimately getting the fingers into a concealed relation behind the margin of the cover, the blank is first drawn to provide an upstanding or axially outwardly projecting annular rib in line with the outer wall of which are the retaining fingers and on a diameter that is substantially less than the ultimately desired cover perimeter. Then the rib is collapsed and radially outwardly bent over into concealing relation to the fingers and to the ultimately desired diameter of the cover perimeter. This method is disclosed and covered in my Patent 2,707,449 dated May 3, 1955.

However, under certain circumstances such as design characteristics, or otherwise, it may be desirable to accomplish substantially the same general result without bending the margin of the cover over, but to bend the retaining fingers in under the margin of the cover. It is to the latter mode of accomplishing the result that the present invention is directed.

It is accordingly an important object of the present invention to provide improvements in the making of sheet metal wheel covers wherein marginal cover retaining fingers are initially shaped on substantially the ultimate perimeter of the cover and are then relocated in concealed relation behind the margin of the cover.

Another object of the invention is to provide an improved method of making wheel covers with marginal integral spring retaining fingers.

A further object of the invention is to provide novel means for shaping the retaining fingers in the making of sheet metal wheel covers.

Still another object of the invention is to provide a new and improved method of making sheet metal wheel covers according to which integral marginal retaining fingers of a cover blank are turned under behind the cover margin in a novel manner.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of a preferred embodiment thereof taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is an outer side elevational view of a wheel structure embodying features of the invention;

FIGURE 2 is a fragmentary enlarged radial sectional detail View taken substantially on the line III[ of FIG- URE 1;

FIGURE 3 is a fragmentary edge elevational view of the cover of FIGURES l and 2; V

' FIGURE 4 is a fragmentary radial sectional detail ice view through a wheel structure similar to FIGURE 2 but showing a modified form of the cover;

FIGURE 5 is a fragmentary radial vertical sectional detail view through die apparatus for shaping the retaining finger structure of a cover blank;

FIGURE 6 is a view similar to FIGURE 5 but showing the apparatus at the conclusion of a finger-forming stroke;

FIGURE 7 is a fragmentary radial sectional detail view through the cover after the retaining fingers have been completed;

FIGURE 8 is a fragmentary radial sectional detail view showning a cover of the type disclosed in FIGURE 4 but in a preliminary stage of formation of the retaining finger structure thereof;

FIGURE 9 is a view similar to FIGURE 8 but showing the retaining finger structure after being turned under; and

FIGURE 10 is a view similar to FIGURES 8 and 9 showing the retaining finger structure after completion.

Having reference first to FIGURES l, 2 and 3, a wheel cover 15 made according to the method of the present invention is constructed and arranged to be applied in press-on, pry-off relation to the outer side of a vehicle wheel including a wheel body 17 and a tire rim 18 supported thereby and of the drop center, multi-flange type including an intermediate generally radially inwardly facing flange 19 merging with a generally radially and then axially outwardly turned terminal flange 19a on a juncture 20. The tire rim is adapted to support a pneumatic tire 21.

By preference, the cover 15 is made from suitable sheet material such as stainless steel or brass adapted to be shaped by cold pressing or drawing. A central portion 22 of the cover is adapted to overlie the wheel body 17 and is connected by an inwardly dished annular portion 23 to a generally radially and axially outwardly directed annular marginal portion 24 of generally oblique angularity and adapted to overlie the tire rim 18 and more particularly the intermediate flange 19 and the shoulder 20.

For retaining the cover 15 on the wheel, it is provided with means behind the outer marginal portion 24 for retainingly engaging the tire rim. To this end, the outer marginal portion 24 has integrally in one piece therewith and disposed in underturned relation therebebind a generally axially and radially inwardly turned annular continuous flange 25 providing at the edge of the cover a turned reinforcing and finishing juncture 27 with the marginal portion 24.

It will be observed in FIGURE 2 that the undertumed flange 25 provides a shoulder which is adapted to seat upon the rim shoulder 20 and since it is of generally frust-conical form coacts with the shoulder 22 to center and define the axially inner limit of the cover upon the wheel.

Extending generally axially inwardly from the inner terminus of the flange 25 is a plurality of cover retaining fingers 28 having angular junctures 29 with the flange 25 and being of substantial width but relatively short length (FIGS. 2 and 3), with side portions thereof flaring from the tips of the fingers into merging relation to the inner edge of the underturned flange 25. This provides side wing-like reinforcement portions 30 for the fingers and since the fingers are of substantial width they arcuately conform to the circumferential curvature of the cover and are thus of substantial resilient stiffness. At their inner extremities the retaining fingers are provided with short and stiff radially and axially outwardly oblique cover retaining terminals 31 which are retainingly engageable in gripping edgewise generally biting engage ment with the inner face defining the intermediate flange 19 of the wheel. By preference, the fingers 28 are notched out as at 32 in order to sub-divide the same into a plurality of individudal finger sections for enhancing the self-equalizing, wheel flange surface accommodating functioning of the fingers. Y

By preference, there are four of the retaining fingers 28 as indicated in dash, outline in FIGURE 1 and these can conveniently be derived from the material 'at four corners of an, initially square blank of material. Due to their short length, great width, arcuate curvature, flaring sides 30, substantial reinforcement by the juncture rib 29, and the short and stiff nature of the retaining terminals 31, strong resilient tensioned thrust of the tips of the retaining terminals 31 is generated against the intermediate flange 19 when the cover is pressed home onto the wheel and the retaining terminals 31 are cammed radially inwardly from a slightly larger diameter along the inner face of the intermediate flange 19, and as enabled by resilient flexure radially inwardly of the retaining fingers 28.

Since in the mounted relation of the cover on the wheel, it is desirable to have a valve stem 33 project through a registering aperture 34 in the intermediate cover portion 23, the retaining finger terminals 31 are preferably slightly notched out as at 35 in order to afiord a plurality of corner edges that will bite into the surface of the intermediate flange 19 and retain the cover against turning on the Wheel.

In the form of the invention shown in FIGURE 4, the wheel is the same and therefore the same reference numerals have been used to identify similar parts as in FIGURE 2, but a slightly modified cover 40 is provided which is adapted for retaining engagement with the terminal flange 19a of the tire rim. To this end, the cover 40 includes a central cover portion 41 joined by an intermediate inwardly dished annular portion 42 to a generally radially and axially outwardly oblique outer annular cover portion 43 providing a margin that overlies the tire rim inclusive of the terminal flange 19a. An underturned generally radially and axially inwardly oblique annular reinforcing flange 44 provides a finishing and reinforcing juncture 45 for the edge extremity of the cover. In this arrangement the underturned flange 44 serves as a bottoming seat for the cover margin engageable with the tip of the terminal flange 19a and with the edge extremity 45 preferably located radially inwardly from a continuation of the radially outermost face of the terminal flange if it were projected. This maintains the cover edge 45 clear of the associated tire side wall in the event of a fiat or soft tire. This furthermore facilitates application of a pry-off tool behind the edge of the cover.

For retaining the cover 40 on the wheel, the underturned reinforcing flange 44 is provided with return-bent generally radially and axially outwardly divergent retaining finger extensions 47 which are of a length to engage in retaining thrusting resilient edgewise relation against the radially inner side of the radially inwardly facing extremity portion of the terminal flange 19a.

In forming the wheel cover 15, a sheet metal blank of stainless steel, brass or the like is die stamped or pressed or drawn into the shape shown in FIGURE 5 wherein the central portion 22, the intermediate dished portion 23 and the radially outer slanted portion 24 are all drawn to shape. Also, the marginal flange is up to this point of preferably generally cylindrical shape extending axially rearwardly as shown and with the finger extensions 28 in line therewith, that is, extending generally axially in the same plane as the flange 25. By preference, the retaining terminal flanges 31 extend radially outwardly normal to the plane of the flange 25 and the body portions of the fingers 28.

In the apparatus of FIGURES 5 and 6, bending under of the flange 25 and at the same time positioning of the retaining fingers 28 in concealed relation behind the outer marginal. cover portion 24 is effected. To this end, the

die apparatus includes a central or anvil supporting die member 50 cntoured to fit within the central portion 22 of the cover and to receive the dished portion 23 and most of the outer annular portion 24 of the cover. At its radially outer perimeter, the die portion 50 is provided with a radially facing axially extending die surface 51 disposed on the diameter radially inwardly from the edge of the cover to which the inner faces of the retaining fingers 23 are to be displaced radially inwardly from the generally cylindrical initial formation of the retaining fingers.

Clamping-1y cooperable with the supporting anvil die member or portion 50 is an upper separably related die member or portion 52 having contours complementary to the upper or outer surface of the cover blank, inclusive of the entire outer marginal cover portion 24 and provided with an annular reentrant seat 54 for the edge rib 27 of the cover, there. being a radial overlying surface 55 of the die portion 52 extending radially outwardly beyond the seat 5 4.

For bending under the marginal flange 25 and radially inwardly shifting the retaining fingers 28, radially reciprocable die means are provided, herein comprising a series of segmental finger die members 57 reciprooably supported by die means which may comprise a die ring member 58 encircling the die member 50. If desired, the die elements 57 may be of the cam die type operable more or less on the order of the cam die arrangement disclosed in my Patent 2,744,426 issued May 8, 1956.

Normally, the cam die elements 57 are backed off clear of or radially outwardly beyond a recess 59 in the upper inner marginal portion of the die member 58 for clearing the depending retaining fingers 28 and partially formed up retaining terminal flanges 31 of the cover member.

In operation, the segmental flange bending and finger shifting die members 57 are driven radially inwardly until finger engaging nose portions 60 thereof engage thrustingly against the radially outer sides of the finger portions 28. It will be understood that the nose portion 60 of the die segments are conformed to engage the finger portions 28 substantially uniformly. The upper extremity of the finger-abutting nose faces or tips merge into a fulcrum shoulder 61 from which leads an oblique flange engaging surface 62 on the respective segment dies 57. As a result, upon continuation of the radially inwardly thrusting, forming movement of the die segments 57, the marginal flange 25 of the cover blank is progressively bent to swing generally radially inwardly about the marginal juncture 27. Since the retaining finger extensions 28 are of substantial width and curved in the circumference of the cover, they substantially resist the inwardly swinging or turning thereof, and this resistance is substantially enhanced by the reinforcement provided by the angular terminal flanges 31. Hence, bending occurs about the fulcrum shoulders 61 of the segment die members 57, with the retaining finger extensions 28 remaining substantially in their axially extending relation while being shifted radially inwardly as bending-under of the flange 25 takes place. At the end of the forming stroke of the segment die members 57, the retaining fingers 28 are sizingly clampingly thrust against the opposing die surface 51, and the underturned flange 25 is sizingly engaged by the oblique forming surfaces 62 of the die segment members. At the same time, a complementary sizing shoulder of groove-like form 63 at the upper, radially outer end of the forming surface 62 engages the radially outer portion of the edge rib 27 in sizing relation. This relationship is shown in FIGURE 6.

Since bending the marginal flange 25 under as described, involves actually reducing the diameter thereof progressively from the juncture 27 to the inner extremity of the flange, wrinkling or buckling is a hazard. However, I have found that by limiting the underturned oblique angle of the finished flange 25 to not substantially in excess of 45 from the cylindrical condition of the flange, such buckling or warping or distortion is substantially minimized. At least, any slight waviness or distortion from a true frustcrconical relation is not commercially undesirable since the flange is concealed behind the substantially accurately finished overlying cover portion 24.

After the marginal flange and finger structure has been shaped as described in the die structure of FIGURES 5 and 6, the segment cam die members 57 are backed ofi and the upper clamping and forming die member 52 is also backed off and the cover member removed from the die assembly. Then, the terminal flange portions 31 are bent up into the oblique radially and axially outward relationship wherein they are ready to be engaged with the tire rim of the wheel with which the cover may be assembled. This bending up is depicted in FIGURE 7.

Shaping of the cover 40 is adapted to be efliected in substantially the same manner, as shown in FIGURES 8, 9 and 10. Thus, initially the sheet metal blank from which the cover member 40 is made is drawn to provide the crown portion 41, the intermediate dished portion 42 and the oblique outer marginal portion 43. Also, the marginal flange 44 is preliminarily formed to extend generally axially and cylindrically from the juncture rib 45, with the retaining fingers extending generally radially outwardly. Then, the flange 44 is turned under, and since the fingers 47 in this instance extend angularly from the inner extremity of the flange 44, they swing inwardly and down as shown in FIGURE 9. It will be observed that the flange 44 is also bent under to not substantially in excess of 45 to the original cylindrical position thereof. Finally, the retaining fingers 47 are bent up into the oblique divergent relation as shown in FIGURE ready to be engaged with the rim flange of the wheel with which the cover may be assembled.

In shaping the underturned flange and finger structure of the cover 40 substantially similar die apparatus as shown in FIGURES 5 and 6 may be employed.

It will be understood that modifications and variations may be efiected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

1. In a method of making wheel covers from sheet metal, shaping a metal blank into a circular cover body having axially inner and axially outer faces and with a marginal circular portion provided with an annularly axially inwardly extending substantially cylindrical flange provided with axially inwardly projecting finger extensions, while retaining the cover including the cover marginal portion against distortion, pressing and bending said marginal flange radially inwardly about a fulcrum at junc ture of the fingers with the flange until the flange has attained an underturned oblique relation behind said cover marginal portion, during such pressing and bending of the flange maintaining said finger extensions substantially axially inwardly extending, and at completion of the bending of the flange subjecting the same to sizing pressure and also subjecting said finger extensions to sizing pressure.

2. In a method of making wheel covers from sheet metal, shaping a metal blank into a circular cover body having axially inner and axially outer faces and with a marginal circular portion provided with an annular axially inwardly extending substantially cylindrical flange provided with axially inwardly projecting finger extensions, retaining the cover including the cover marginal portion against distortion, pressing said marginal flange radially inwardly about a fulcrum at juncture of the fingers with the flange until the flange has attained an underturned oblique relation behind said cover marginal portion, while maintaining said finger extensions substantially axially inwardly extending, and at completion of the bending of the flange subjecting not only the flange but also juncture of the flange with the cover marginal portion and also said finger extensions to sizing pressure.

3. In die apparatus for making wheel covers, a lower die structure for supporting a circular cover blank thereon with a depending substantially cylindrical marginal flange on the outer marginal portion of the cover blank, an upper die structure adapted to engage separably with the cover blank to clamp the same against the lower die structure and having a portion for engageably overlying the outer marginal portion of the cover blank, said lower die structure being of a substantially smaller diameter than said portion of the upper die structure so as to afford a substantial radial clearance from said flange of the cover blank, and die means about the lower die structure including reciprocable cam die members having generally upwardly facing and downwardly and inwardly sloping oblique forming surfaces adapted to engage with the marginal flange of the cover blank upon radially inward bending thrust thereagainst of the cam die members to swing and bend the marginal cover flange within said clearance into underlying oblique downwardly and inward relation to the cover margin, said lower die structure and said cam die members having below said generally upwardly facing forming surfaces cooperating opposing sizing die surfaces for engaging retaining finger extensions on said cover flange at the completion of the bending of the flange into said oblique relation.

4. In apparatus for making wheel covers, upper and lower die structures for engaging a circular cover member therebetween having axially inner and axially outer sides and with the lower die structure having a radially inward clearance for accommodating a generally axially inwardly directed marginal flange of the cover blank in spaced relation, and a plurality of reciprocable thrust die members for engaging and radially inwardly bending the cover marginal flange in under the marginal portion of the cover, said reciprocable die members and the upper die structure having opposing cover edge sizing surfaces cooperable to engage therebetween the juncture of the cover flange with the marginal portion of the cover at the conclusion of the bending stroke of the reciprocable die members.

5. In a method of making wheel covers from sheet metal, shaping a metal blank into a circular wheel cover body having axially inner and axially outer faces and including a circular radially outer marginal portion with a generally axially inwardly cylindrical turned marginal flange provided with retaining finger extensions incuding portions affording retaining terminals projecting generally radially outwardly from the flange and edge portions of the flange intervening between said finger extensions, while holding said outer marginal cover portion in a substantially fixed condition relative to the cover body, bending said flange obliquely behind the axially inner side of said outer marginal cover portion and moving said edge portions and said finger extensions inclusive of said portions which afford the retaining terminals into concealed relation behind said marginal portion, and then bending said retaining finger extension portions into oblique relation behind the oblique flange to project radially and axially outwardly and thereby completing the formation of the retaining fingers.

6. In a method of making wheel covers from sheet metal, shaping a metal blank into a circular cover body having axially inner and axially outer sides and having a radially outer marginal circular portion with a generally cylindrical axially inwardly extending marginal flange provided with edge portions from which project retaining finger extensions; forming at least portions of the finger extensions to project angularly radially outwardly relative to the flange; while holding said outer marginal cover portion in a substantially fixed condition relative to the cover body, bending in behind the axially inner side of said marginal portion said marginal flange while maintaining said retaining fingers in said angular relation thereto but moving said edge portions and said finger extensions into concealed relation behind said marginal portion; and after the flange has been bent in bending said portions of the marginal flange to project radially and axially outwardly and thereby completing the retaining fingers.

7. In a method of making wheel covers from sheet metal, shaping a metal blank into a circular cover body having axially inner and axially outer faces and with a marginal circular portion provided with an annular axially inwardly extending substantially cylindrical flange provided with axially inwardly projecting finger extensions, while retaining said cover marginal portion against distortion pressing and bending said marginal flange radially inwardly about a fulcrum at juncture of the fingers with the flange until the flange has attained an underturned oblique relation of not substantially over 45 from the original substantially cylindrical shape thereof behind said cover marginal portion, during such pressing and bending of the flange maintaining said finger extensions substantially axially inwardly extending, and at completion of 8 the bending of the flange subjecting the same to sizing pressure and also subjecting said finger extensions to sizing pressure."

References Cited the file of this patent UNITED STATES PATENTS 620,479 Mittinger Feb. 28, 1899 1,708,615 Groehn et a1 Apr. 9, 1929 1,774,809 Muhlbach Sept. 2, 1930 1,776,888 Clark Sept. 30, 1930 1,828,464 Harrison Oct. 20, 1931 2,271,107 Swangren Jan. 27, 1942 2,659,407 Kay Nov. 17, 1953 2,681,027 Boll June 15, 1954 2,707,449 7 Lyon May 3, 1955 FOREIGN PATENTS 469,279 Canada Nov. 14, 1950 471,604 Canada Feb. 20, 1951 471,721 Canada Feb. 27, 1951

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