GB2365395A

GB2365395A - Adjustable vehicle spare wheel suspension assembly

Info

Publication number: GB2365395A
Application number: GB0018894A
Authority: GB
Inventors: Leigh Platts
Original assignee: Dura Automotive Ltd
Current assignee: Dura Automotive Ltd
Priority date: 2000-08-02
Filing date: 2000-08-02
Publication date: 2002-02-20
Anticipated expiration: 2020-08-02
Also published as: GB0018894D0; GB2365395B

Abstract

The assembly (21) includes two tubes (240, 245) interconnected to form a telescopic arrangement. The two tubes (240, 245) are interconnected by a spring (247) acting between the flanges (240c, 245a) which tends to shorten the assembly. This arrangement allows adjustment of the length of the assembly to accommodate wheels of varying width. The assembly also includes a cable (214) connected to a winch mechanism at one end and resiliently connected by spring (217) to tube (240) at the other. In use a wheel engaging member (248) includes a spigot (250) which passes though the centre hole of the wheel to be suspended. The spigot (250) has a bayonet (256) which cooperates with slot (255) in the outer tube (245) to form a releasable connection. The winch mechanism is operated until the wheel contacts the underside of the vehicle and spring (247) is compressed sufficiently to accommodate the width of the wheel and to allow engagement of a safety catch with the mushroom shaped washer (219). The safety catch restrains the wheel in the event of a failure of cable (214).

Description

<Desc/Clms Page number 1> ADJUSTABLE VEHICLE WHEEL SUSPENSION ASSEMBLY This invention relates to a vehicle wheel suspension assembly for use with a winching mechanism, in which the assembly includes a winch cable for suspending a vehicle spare wheel; and a size adjustment feature.

EP-A-0 612 653 discloses a winch comprising a winching mechanism and a safety catch in a common housing. A winch cable is provided for suspending a vehicle spare wheel in a stowed position under a vehicle chassis. The safety catch operates to prevent the wheel from lowering to the ground in the event that the suspension by the cable fails, e.g. by breaking. In order to do this, the catch is normally in an operative position to prevent lowering of the wheel to the ground. When it is desired purposely to lower the wheel from the stowed position, a tool is inserted into a socket and over a hub of the winching mechanism and rotated in order to apply a drive force to the winching mechanism to cause unwinding of the cable. Insertion of the tool in the socket automatically moves the safety catch from the operative position to a retracted position in which the catch does not prevent lowering of the wheel to the ground.

GB 2 306 936 A discloses another kind of winch, in which the suspension cable biases a safety catch to a disengaged position. In the event of the cable breaking the biasing of the safety catch relaxes with. the result that the catch engages a cup- or mushroom-shaped washer to prevent the vehicle wheel from falling more than a short distance below the underside of the vehicle carrying it.

Hitherto, vehicle wheel suspension assemblies such as those shown in EP-A-0 612 653 and GB-A-2 306 936 have had to be specifically designed and manufactured to accommodate a single width of wheel/tyre

combination (ie. that of the spare wheel of a particular vehicle). It has not been possible to devise a width adjustable suspension assembly, primarily because the location at which the safety catch engages the mushroom- shaped washer must be substantially invariant in order to assure catching of the suspension assembly by the safety catch in the event of winching cable failure.

According to the invention there is provided a vehicle wheel suspension assembly as defined in Claim 1.

The use of first and second members that are moveable one relative to the other, to define the body of the suspension assembly, means that the length of the suspension assembly can be adjusted to accommodate wheels of varying widths without affecting the position of the mushroom-shaped washer. Therefore the location at which the safety catch and mushroom- shaped washer engage one another with be substantially invariant, regardless of the width of wheel carried on the suspension assembly.

The use of biasing means (that preferably are resilient) to urge the first and second members to shorten the suspender permit the effective supporting of both narrow and wide vehicle wheels.

Investigations to date indicate that the arrangement of the invention can readily accommodate vehicle wheel widths at least in the range 114mm - 139mm.

In a prefer-red embodiment the assembly is as defined in Claim 2.

The use of a hollow cylinder as one of the first and second members, encircling and slideably retaining the other of the said members, confers

compactness on the suspender forming part of the invention.

The use of a hollow cylinder also advantageously permits the construction of the formations as annular flanges that prevent separation of the first and second members from one another.

Conveniently the biasing means act as defined in Claim 3. This arrangement also conveniently suits the use of annular flanges in a pair of "nested" cylinders.

Conveniently the biasing means is as defined in Claim 4, although of course another resilient biasing means such as a rubber block or leaf spring may of course be employed within the scope of the invention.

Preferably the third member is releasably securable to the second member, as defined in Claim 5.

This permits the third member to pass through an aperture in a vehicle wheel, before attaching of the third member to the second member.

This feature facilitates removal and replacement of a wheel carried by the assembly.

More specifically, the attachment is as defined in Claims 6 to 8.

The features of these claims ensure ease of use of the third member, while preventing the vehicle wheel from swinging relative to the remainder of the assembly during winching operations.

The features of Claims 6 to 8 may if desired be employed in conjunction

with other suspension assemblies that omit the features of Claims I to 5. Such arrangements would lie within the scope of an aspect of the invention. There now follows a description of a preferred embodiment of the invention, by way of non-limiting example, with reference being made to the accompanying drawings in which: Figure I is a prior art winch having a safety catch in a retracted position, as disclosed in EP-A-0 612 653; Figure 2 shows detail of the safety catch of the winch of Figure 1, but in the operation position; Figure 3 shows a winch as disclosed in GB-A-2 306 936; Figure 4 shows a suspension assembly, according to the invention, that is capable of accommodating a range of vehicle wheel widths; and Figure 5 shows an example of use of the suspension assembly of Figure 4 in conjunction with a winch and safety catch assembly.

Referring to Figures I to 3, the prior art winch 10 comprises a wheel bracket 11, which is used in a conventional manner to bolt to a vehicle spare wheel (not shown), for stowing the wheel under a vehicle chassis (not shown). The winch comprises a winch cable device including a suspension device and a winch cable 14. The bracket I I is suspended by the suspension device. The winch 10 comprises a casing which includes an elongate, cylindrical housing 22 having a space 23. The winch cable device includes guide means in the form of a guide assembly 32, which has a cup- shaped plate 19 and is suspended from the cable 14 and extends across the space 23 to the housing wall 24. The winch cable is fastened to a self- locking winch mechanism 31 which is actuable by rotation of an actuating shaft 7 1.

A safety catch is provided comprising an arm 25 pivotally attached at a

pivot point 26 to the outside of the casing, the pivot point 26 being intermediate the ends 27, 28 of the arm 26. The arm 25 has a catch portion in the form of a hook 29 at one end 28.

In the prior art arrangement, as shown in Figures 1 and 2, the arm 25 is biased by a return spring 200 to an operable position in which the hook 29 projects through an opening 30 in the housing wall 24 and into the space 23. In use,, a tool (not shown) is engaged with a hexagonal hub 70 on the shaft and rotated, thereby rotating the actuating shaft, unwinding the winch cable 14 and lowering the bracket 11 from the vehicle chassis. The arm 25 is moved from the operable position to a retracted position (Figure 1) against the bias, when the tool is engaged on the hub 70. The tool engages the end part 27 of the arm to effect this movement. In the retracted position, the hook 29 is retracted from the opening 30, so that the hook is clear of the space 23 and the cup-shaped plate 19 is free to move past the opening 30 as the winch cable is unwound. The guide assembly 32 acts to guide longitudinal movement in the housing 22.

In the event of failure of the cable, the wheel bracket 11 moves away from the vehicle chassis and the cup-shaped plate 19 moves in the space 23 towards the hook 29 that occupies the space 23. Engagement of the hook 29 and the plate 19 limits further movement of the wheel bracket 11.

In Figure 3 a vehicle spare wheel 160 is shown suspended from the cable 114 by a bracket I I I in a manner similar to that of Figures I and 2.

The Figure 3 safety catch includes a cranked arm 125 pivotally mounted to the housing at a pivot point 126 and projecting through an opening 170 in the housing wall 124. A roller 127 is rotatably provided at an end part of

the arm 125 and the arm is formed into a hook 129 at the opposite end part of the arm. The roller engages the cable 114, and the hook 129 faces the cup-shaped plate 119.

A spring 140 biases the arm 125 to the position shown in phantom in Figure 3, in which the hook 129 is in a catch position, to catch a peripheral part of the cup-shaped plate 119. The arm is, however, held against the bias so that the hook 129 is in a retracted position. The tensioned cable 114 is engaged by the roller 127 to hold the arm against the bias in this retracted position, in which the hook 129 is free of the plate 119 (solid line in Figure 3).

If suspension of the wheel by the cable 114 fails because the cable breaks (phantom line in Figure 3) or becomes disconnected from the winching mechanism while the wheel 160 is stowed under the vehicle chassis, the tension on the cable 114 is released. The arm 125 is then no longer held against the bias, and the arm 125 automatically moves under the action of the spring 140 to the catch position in which the hook 129 can catch the plate 119 (phantom line in Figure 3), thereby acting as a safety catch to prevent the spare wheel from dropping to the ground.

Figures 4A to 4D show a modified form of suspension assembly that may form part of the arrangement of either Figures I and 2 or of Figure 3, and that permits the suspension of a range of vehicle wheel widths (presently between 114min and 139mm).

Figure 4A shows the suspension assembly, in cross section, in its retracted configuration. Figure 4B shows the external appearance of the assembly in Figure 4A, viewed at right angles to the Figure 4A view.

Figures 4C and 4D are views, corresponding to the Figures 4A and 4B

views, showing the assembly of the invention in its extended configuration. For clarity, Figure 4 omits the safety catches 25, 125; the housings 22, 122; and related components.

The vehicle wheel suspension assembly 210 of Figure 4 comprises a winch cable 214 and a suspender 212 for suspending a vehicle wheel from the cable 214.

The upper end of cable 214 (not visible in Figure 4) is connectable to a wincbing mechanism, such as those described in Figures I to 3, forming part of the winching and safety catch arrangement of the assembly. The purpose of the winching mechanism is to raise and lower the wheel to and from a stowed position.

Suspender 212 is connected to cable 214 by virtue of being securely received in the upper end of a threaded bolt 215 that protrudes downwardly at the top of the assembly 2 10.

The lower end of bolt 215 terminates in a nut 216 including an outwardly directed flange 216a that supports a compression spring 217 that is coiled about bolt 215 above nut 216.

Suspender 212 includes a first, bollow, cylindrical member 240 that extends vertically.

At its upper end, cylindrical member 240 terminates in an inwardly directed flange 240a having formed therein a central, circular aperture. Cylindrical member 240 encircles bolt 215, that passes through the aperture 240b.

Compression spring 217, that rests at its lower end on flange 216a, engages the underside of flange 240a, whereby member 240 is suspended relative to bolt 215 and cable 214.

The purpose of compression spring 217 is to damp the cable 214.

Suspender 212 also includes a second member 245 in the form of a second, hollow, cylindrical member of larger diameter than member 240.

Members 245 and 240 are slideably captive one relative to the other, whereby the overall length of suspender 212 is ad ustable.

Ii This is achieved by virtue of the upper end of cylinder 245 terminating in an inwardly directed flange 245a having formed therein a central, circular aperture 245b.

The diameter of aperture 245b is only slightly larger than the outer diameter of member 240, whereby second member 245 may slide along the length of the exterior of first member 240.

The lower end of first cylindrical member 240 terminates in an outwardly directed flange 240c, whose outer diameter is only slightly smaller than the inner diameter of second hollow cylindrical member 245.

The diameters of flange 240c and aperture 245b are such as to ensure that the members 240, 245 remain substantially coaxial with one another during sliding one relative to the other.

The presence and chosen diameters of the essentially juxtaposed flanges 245a and 240c mean that the second member 245 is captive relative to the

first member 240,, in the sense that member 245 cannot be slid downwardly off the lower end of member 240.

The suspension assembly 210 of the invention includes a biasing means, in the form of further compression spring 247, acting between the first and second members 240, 245.

In practice spring 247 occupies the annular space between the members 240 and 245, encircling the first member 240.

The lowermost end of compression spring 247 engages the upper surface of flange 240c; whereas the upper end of compression spring 247 engages the underside of flange 245a, whereby compression spring 247 biases suspender 212 towards its shortened configuration shown in Figures 4A and 4B.

Suspender 212 includes a third member 248 in the form of a carrier foot 250 and wheel seat 251 assembled together.

Third member 248 is releasably securable relative to second member 245 in a manner described in further detail below.

Suspension assembly 210 also includes a catch engager in the form of mushroom-shaped washer 219 secured immediately beneath the head of bolt 215.

Washer 219 terminates at its outer periphery in a downwardly directed flange 219a that is engageable by a safety catch such as catch 25 shown in Figures I and 2 or catch 125 shown in Figure 3.

Mushroom-shaped washer 219 is supported in position and spaced from the

suspender 212 by virtue of a spacer 252 that is in essence a hollow cylinder encircling bolt 215 along its length between the upper flange 216a of nut 216 and the underside of mushroom-shaped washer 219.

A short distance below its upper end, spacer 252 thickens to present a downwardly facing shoulder 253 that acts as a stop limiting upward movement of first member 240.

Spacer 252 preferably is formed from plastics material, although of course other materials are possible.

Carrier foot 250 is formed essentially as a downwardly extending, hollow, cylindrical member.

On opposite sides of the cylindrical body of carrier foot 250 there is formed an essentially J-shaped slot 255 that terminates in an open upper end at the free, upper end of carrier foot 250.

The J-shaped slots 255 on opposite sides of carrier foot 250 are respectively left and right handed, to permit insertion therein of a bayonet 256 in the form of a rigid pin extending diametrically across the interior of the lower end of second member 245.

Each J-shaped slot 255 is so positioned and shaped that, on upward movement of carrier foot 250 to insert the bayonet 256 into the slots 255, whereby the bayonet 256 reaches the bottoms of the slots the carrier foot 250 may be rotated to permit the carrier foot 250 subsequently to drop relative to bayonet 256. This causes the bayonet 256 to seat as shown in Figure 4A in the respective slots 255.

Opposed sides of bayonet 256 have formed thereon respective vertically extending flats 257.

The portion of each J-shaped slot 255 in which the bayonet seats is correspondingly shaped. Consequently, when bayonet 256 is seated as shown in Figure 4A in the ends of the respective J-shaped slots 255 the carrier foot 250 does not rotate about the longitudinal axis of bayonet 256. The carrier foot 250 therefore is suspended in a stable position relative to second member 245, The lowermost end of carrier foot 250 terminates in an outwardly directed flange that supports an annular wheel seat 251. Wheel seat 251 may if desired be shaped to suit the formations on a vehicle wheel to be supported on the apparatus.

In use of the suspension assembly of the invention, the third member 248 is first detached from second member 245, by a combination of liffing to disengage bayonet 256 from the ends of the slots 255; rotation of the carrier foot 250 and subsequent lowering of carrier foot 250 to free it completely from the lower end of second member 245, Carrier 250 is then passed through eg. the centre aperture of a vehicle wheel, whereby the wheel is supportable on wheel seat 25 1.

Carrier foot 250 is then reattached to second member 245, by re-engaging the bayonet 256 in the slot 255 following a reverse of the removal procedure.

The winch (not shown in Figure 4) is then operated until the tyre of the vehicle wheel contacts eg. the underside of the vehicle, with the

compression spring 247 during this process lengthening as necessary to accommodate the width of the wheel, As a final step a safety catch such as member 25 may be moved to a safety position, engaging the underside of mushroom-shaped washer 219, to restrain the vehicle wheel in the event of cable failure. This arrangement is shown in exemplary fashion in Figure 5, in which the winch and safety catch assembly is essentially of the kind shown in Figures I and 2.

In an alternative arrangement the safety catch may be as shown in Figure 3, whereby it only operates to engage mushroom-shaped member 219 in the event of cable failure.

Other forms of winch and safety catch may within the scope of the invention of course be used in substitution of those shown.

Removal of a vehicle wheel from the suspension assembly is, in essence, the reverse of the procedure for securing a vehicle wheel thereto.

Preferably the vehicle wheel is supported on the suspension assembly with its outermost face directed downwardly. For this reason the wheel seat 251 preferably is formed from a non-scratching material such as a plastics material.

The remainder of the components of the suspension assembly may be formed as appropriate eg. from various metals or plastics materials, as desired.

The choice of the diameters of the members 240 and 245 ensures that movement of the vehicle wheel relative to the remainder of the assembly is

substantially stable in both the axial and radial dimensions.

Since the cable 214 is flexible, as the suspension assembly 210 approaches the winch the location of the vehicle wheel is automatically centralised relative to the vehicle winch.

The provision of the third member 248 as a detachable item that passes through the centre bore of the vehicle wheel allows the wheel seat 251 to be of a large diameter, thereby providing a stable support that is larger than the centre bore of the wheel.

The fitting of the carrier foot 250 into the hollow, open, lower end of the second member 245 facilitates assembly of the device.

Claims

CLAIMS I. A vehicle wheel suspension assembly for use with a winching and safety catch arrangement, the assembly comprising a winch cable and a suspender for suspending a vehicle wheel from the cable, the cable being connectable to a winching mechanism, for raising the wheel to or lowering the wheel from a stowed position, the suspender including a first member connected to the cable; a second member, the first and second members being moveably captive one relative to the other whereby the length of the suspender is adjustable; a biasing means acting between the first and second members tending to shorten the suspender; a third member engageable with a said vehicle wheel; and a catch engager for engaging a safety catch.
2. An assembly according to Claim I wherein at least one of the first and second members is a hollow cylinder, the other of said first and second members being slideably received within the hollow cylinder and the first and second members respectively including formations limiting their movement one relative to the other whereby the first and second members are moveably captive one relative to the other.
3. An assembly according to Claim 2 wherein the biasing means acts between the respective formations of the first and second members.
4. An assembly according to Claim 3 wherein the biasing means is or includes a compression spring interconnecting respective formations of the first and second members.
5. An assembly according to any preceding claim wherein the third member is releasably securable, via an attachment means, to the second member.

<Desc/Clms Page number 15>
6. An assembly according to Claim 5 wherein the attachment means includes a bayonet rigidly protruding from the second member; and a socket, formed in the third member, with which the bayonet is selectively engageable.
7. An assembly according to Claim 5 wherein the socket is or includes an open ended, J-shaped slot formed in the third member, the bayonet being slideable along the slot to a wheel supporting position in which the third member is suspended from the second member.
8. An assembly according to Claim 7, wherein the bayonet and slot engage one another, when the bayonet occupies the said wheel supporting position, so as to limit or prevent rotation of the third member relative to the bayonet.
9. An assembly generally as herein described, with reference to and/or as illustrated in the accompanying drawings.