Apparatus for attaching a flexible annular member to a rigid member

Apparatus is disclosed for attaching a flexible annular member to a rigid member using an annular tongue on an annular bead on one of the members that is engageable in an annular groove in an annular bead on the other member, and further using a preformed resilient lock ring that is split so as to have oppositely facing ends and has a C-shaped cross-section with a radially outwardly facing peripheral side so as to be mountable over and then clamp together and hold the beads on the members with their tongue and groove engaged.

TECHNICAL FIELD 
This invention relates to apparatus for attaching a flexible annular member 
to a rigid member and more particularly to apparatus for making the 
attachment using beads on the respective members that have a tongue and 
groove engagement and further using a split lock ring that captures and 
clamps the beads together to attach the members. 
BACKGROUND OF THE INVENTION 
In the attachment of a flexible annular member to a rigid member such as 
that of a so-called "flexible edge" to a wheel cover to make the wheel 
cover larger in diameter yet deflectable when the tire is severely 
distorted, it has been common practice to use intermittent attachment such 
as heat staked projections and a metal band where the rigid wheel cover is 
plastic and also various forms of clips. In the case of heat staked 
plastic projections, there are resulting sink marks in the wheel cover 
along with a substantial space limitation to make the attachment. 
Furthermore, such an attachment reduces the flex length in the flexible 
edge. And whether such heat staked projections or separate clips are used, 
the flexible edge is not attached securely therearound resulting in 
possible mismatch between the flex edge and the cover at the external or 
appearance surface. 
It is known in general that two rigid members may be attached together at 
an annular junction thereof by a resilient split ring or band that clamps 
together beads on these members but it has been found that there is 
substantial difficulty in actually carrying out such an assembly where one 
member is flexible because of the lack of inherent support in the latter 
member for such ring assembly and also because of interferences imposed by 
the members in the assembly to the application of suitable ring assembly 
apparatus. Moreover, this problem in assembly is made greater where a 
tongue and groove engagement between the members is desired to improve 
their relative locations. 
SUMMARY OF THE INVENTION 
The apparatus according to the present invention solves these problems and 
in a cost-effective manner with very simple componentry. The apparatus is 
particularly adapted to attaching a flexible annular member such as a 
flexible edge to a rigid member such as a wheel cover using an annular 
tongue on an annular bead on one of the members that is engageable in an 
annular groove in an annular bead on the other member and further using a 
preformed resilient lock ring that is split and is mountable over and then 
clamps together and holds the annular beads on the members with their 
tongue and groove engaged. The apparatus comprises a rotary table on which 
a plurality of support members are annularly arranged and guided for 
radial movement between a stop position and a radially inwardly located 
lock ring assembly position. Separate springs normally hold each support 
member in a stop position and resist radial inward movement to its lock 
ring assembly position. The flexible edge with the lock ring mounted on 
the bead thereon is supported on all of the support members while in their 
stop positions while a locator on each of the support members serves to 
locate the flexible edge concentric with the rotary table and hold same in 
a radially outwardly expanded condition so as to centrally receive the 
wheel cover with radial clearance. A positioning device provides for 
forcibly positioning the wheel cover so that its bead bears against the 
bead on the flexible edge while the latter is located and supported in 
expanded state on the support members. A roller mounted separate from and 
radially movable relative to the rotary table moves from a retracted 
position to an extended position operates to engage the lock ring near one 
of its ends and move same radially inward on the associated support 
members against their springs. This inward movement forces the one end of 
the lock ring to snap over the bead on the wheel cover and thus over the 
bead on both the flexible edge and the wheel cover while also snapping the 
tongue into the groove on the beads. A drive is then operated to rotate 
the rotary table while the roller is in its extended position engaging the 
lock ring to thereby cause the roller to roll along and force the lock 
ring into position about both the beads along their length to complete the 
attachment.

Referring to FIGS. 1 and 4, there is shown a wheel cover 10 of rigid 
plastic and circular shape to which a flex edge 12 of flexible plastic and 
annular shape is attached to the periphery thereof prior to the assembly 
of the wheel cover on a motor vehicle wheel 14. The purpose of the flex 
edge is to make the wheel cover appear larger in diameter yet be 
deflectable when the tire 16 that is mounted on the wheel is severely 
distorted such as by encountering bumps on cornering maneuvers. The wheel 
cover with the flex edge mounted thereon is attached to the wheel by a 
plurality of circumferentially spaced clip devices. These devices, as best 
seen in FIG. 4, include a metal spring 17 having barbs 18 that engage in a 
radially inwardly facing annular recess 20 in the exterior of the wheel 
rim to retain the cover on the wheel. 
The flex edge is attached to the wheel cover by a split lock ring 22 of 
metal and C-shaped cross-section that must be received over and then 
clamps together an annular bead 24 on the wheel cover and a similar 
annular bead 26 on the flexible edge extending about the back side 
thereof. In addition, the flex edge has an inner diameter 28 that is 
received against a shoulder 30 on the wheel cover and in addition has a 
back side portion 32 that is received against a radially extending 
shoulder 34 on the wheel cover so as to align the front face of the flex 
edge with that of the wheel cover and in particularly make them flush at 
their juncture. Moreover, the flex edge bead 26 has an annular tongue 36 
that must engage in an annular groove 38 in the bead on the wheel cover to 
further provide proper location of the flex edge on the wheel cover. 
Apparatus according to the present invention for attaching the flexible 
annular member or edge to the rigid wheel cover member comprises a rotary 
table 40 that is driven about its axis 41 through a suitable drive train 
42 by a motor 44. A plurality of support members 46 are annularly arranged 
on the table and each have a rectangularly-shaped guide portion 48 that is 
received in a complementaryly-shaped radial slot 50 in the top of the 
table so as to be guided thereby for radial movement on the table between 
a stop position shown in FIG. 2 and a lock ring assembly position shown in 
FIG. 3 as will be described in more detail later. A coil spring 52 is 
mounted in concentric counter bores 54 and 56 in the table and each 
support member respectively and operates to separately normally hold each 
support member in its stop position and resist radially inward movement to 
its lock ring assembly position. In addition, each support member has a 
flat support surface 57 on the top side thereof that is adapted to support 
the flexible annular member 12 with the lock ring 22 having been 
previously mounted thereon as shown in FIG. 2. Moreover, each of the 
support members has an upstanding locator 58 in the form of a thin 
upwardly axially extending shoulder against which the inner diameter 28 of 
the flex edge is stretched radially outward to fit against to thus locate 
the flex edge concentric with the rotary table and provide radial 
clearance 59 on the backside of the locators relative to the periphery of 
the wheel cover while the support members are all held in their stop 
position. And positioning means 60 such as an air cylinder is provided 
that is movable axially as shown by the double-headed arrow in FIG. 2 from 
a retracted position to the extended position shown to position the wheel 
cover 10 so that its bead 24 forcibly bears on its groove side against the 
tongue side of the bead 26 on the flex edge just radially inward of the 
location of the associated edge 61 of the lock ring as shown in FIG. 2. 
A roller 64 is mounted on an arm 66 of an actuator 68 such as an air 
cylinder separate from the rotary table and is arranged so as to be 
radially movable relative to the rotary table as shown by the 
double-headed arrow in FIG. 1. The roller is movable from a retracted 
position (FIG. 2) to an extended position (see FIGS. 1 and 3) so as to 
slide along the back side of the flexible edge and engage the lock ring 
near one of the ends 69 thereof on the radially outwardly facing 
peripheral side (backside) of the lock ring and then move same radially 
inward on the associated support members against the associated springs. 
With such movement, this end of the lock ring is caused to snap over the 
bead on the wheel cover and thus over the bead on both the wheel cover and 
the flexible edge while also snapping the tongue 36 into the groove 38. 
The drive motor 44 is then activated to rotate the table in the direction 
of the arrow in FIG. 1 while the roller means is in its extended position 
engaging the lock ring to thereby cause the roller to roll along and 
thereby force the lock ring into position about both the beads along their 
length to complete such attachment. After the assembly the been completed, 
the wheel cover positioner and the lock ring roller are retracted to 
permit removal of the wheel cover with the flex edge thus attached by 
lifting same vertically upward off the locators 58. On removal, the flex 
edge returns to its original molded shape and the support members are 
returned under their spring load to their normal position shown in FIG. 2 
in readiness to repeat the operation. 
While the apparatus is shown as adapted to assemble a flex edge to a wheel 
cover, it will be understood by those skilled in the art that the 
apparatus is also adaptable to attaching other forms of flexible annular 
members and rigid members together using a similar lock ring and with or 
without an annular tongue and groove engagement between the beads clamped 
by the lock ring. 
The above described preferred embodiment is thus intended to be 
illustrative of the invention which may be modified within the scope of 
the appended claims.