TRAILING ARM LEAF-SPRING WHEEL SUSPENSION

Abstract: A wheel assembly for a yoke or u-shaped chassis (1) having a trailing arm (7) pivotally connected at one end to the chassis (1). The other end of the trailing arm (7) connected by two pivotally connected brackets (15 and 16) to a leaf spring (14), which is connected at each of its ends to the chassis (1). One end of the leaf spring (14) being pivotally connected to a bracket (18) which is pivotally connected to the chassis (1). A shock absorber (19) is connected between the bracket (16) and the chassis (1) near the bracket (18).

Description: TRAILING ARM LEAF-SPRING WHEEL SUSPENSION The present invention relates to an improved self powered or non powered vehicle having a bed which is moveable between a transport position and a ground engaging loading position and in particular to a wheel assembly for such a vehicle. In one broad form the invention comprises a wheel assembly adapted for connection to a yoke or u-shaped chassis comprising: a trailing arm pivotally suspended from a first end to one arm of the chassis; a wheel stub axle mounting located at or adjacent the free end of the trailing arm; a connection means located on said trailing arm adjacent said wheel stub axle mounting; a first bracket pivotally connected to said connection means of said trailing arm; a leaf spring connected at or adjacent its middle to said bracket ; a second bracket having one end pivotally connected to the chassis on one side of said first bracket and having its other end pivotally connected to one end of leaf spring, with the other end of said leaf spring being connected to the chassis on the other side of said first bracket; and a shock absorber being connected between the first bracket and the chassis adjacent the said second bracket. The invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a plan view of the rear chassis according to one embodiment of the present invention; Figure 2 shows a side elevation of the chassis shown in figure 1 ; Figure 3 shows plan view of a tray according to one embodiment of the present invention; Figure 4 shows a side elevation of the tray shown in figure 3; Figure 5 shows a schematic view of a wheel assembly according to one embodiment of the present invention; Figure 6 shows a section view the connection of the trailing arm connection to the chassis taken in the direction of arrows vi in figure 5; Figure 7 shows a detail view of the connection of the leaf spring to the trailing arm as shown in figure 5; Figure 8 shows a sectional view of the connection of the leaf spring to the trailing arm taken in the direction of the arrows viii in figure 7; and Figure 9 shows an elevation of the trailing arm. The present invention is an modification of the invention described in PCT International patent application no. PCT/AU95/00162, which is incorporated herein by way of reference. The present invention utilises a yoke or u-shaped rear chassis (1 ), as shown in figures 1 and 2, the front of which is attached to the rear of the vehicle cabin (not shown). The chassis (1) comprises two arms (22), extending from end rail (23). Each arm (22) comprises a lower member (24), which has a step (25) intermediate its ends. The lower member (24) being connected to a top rail (26) by stays (27). The end stays (4) being hollow. A tray (2), as shown in figures 3 & 4, comprises a rigid reinforced bed (28) with a suitable floor covering (29), and side walls (30). Located adjacent the corners of tray (2) are guide rods (3). The tray (2) is located between the arms (22) of the chassis (1 ) and is supported thereby in like manner as described in the PCT/AU95/.00162, with the guide rods (3) of the tray (2) telescopically engaging with the end stays (4) of the chassis (1 ). Any suitable raising and lowering means such as hydraulics, cables or worm drives can be used. The chassis can be incorporated to form an open back pick up van or utility, or an enclosed van wherein as shown in figures 3 & 4, the tray (2) has pivotally connected thereto, a short ramp (5), with no tailgate. The rear door being on the body of the chassis. The telescoping connection between the guide rods (3) and the end stays (4) enhances the rigidity of the chassis (1 ). This is also applicable if the guide rods were on the chassis and the stays were on the tray. Further the end stays (4) could incorporate a worm drive motor with the guide rods (3) suitably threaded to be driven by the worm drive motor to move the tray (2) between the ground engaging loading position and the raised transportation position. Similarly the drive means could be a rack located on either the tray or the chassis with a toothed wheel located on the other, whereby rotation of the geared wheel along the rack raises and lowers the tray. A wheel assembly (6) is shown in figure 5 according to one embodiment of the present invention. A trailing arm (7) is pivotally connected to the chassis (1), as shown in figure 6 on a shaft (8) whose outer end passes through a sheath (9) into the annular section (10) of the support plate (11 ). The support plate (11 ) being attached to the chassis brace (12) to transfer the loading of the trailing arm (7) back to the chassis(1 ). Mounted on the free end (13) of the trailing arm (7) is stub axial mounting (20), to which is bolted the stub axial (21 ). The free end (13) of the trailing arm (7) is pivotally connected to the centre of the leaf spring (14) through the member (15) and the spring holder (16), which in this case is supported on a bush (17) on the member (15). One end of the leaf spring (14) is connected to the chassis (1 ) , while the other end is pivotally connected to the member (18), which is pivotally connected to the chassis (1 ). A shock absorber (19) extends from the leaf spring holder (16) to the chassis (1 ) adjacent the member (18). This particular configuration provides a robust suspension system. As is shown in figure 5, the stub axle mounting is positioned behind the step (25) so as to provide adequate room for movement of the components, during use. While as shown in figure 9, the trailing arm (7) is tapered from the stub axle mount end to the other end. It should be obvious that alterations and modifications could be made to the above described embodiment without departing from the scope and spirit of the present invention.

Claims: Claims 1. A wheel assembly adapted for connection to a yoke or u-shaped chassis comprising: a trailing arm pivotally suspended from a first end to one arm of the chassis; a wheel stub axle mounting located at or adjacent the free end of the trailing arm; a connection means located on said trailing arm adjacent said wheel stub axle mounting; a first bracket pivotally connected to said connection means of said trailing arm; a leaf spring connected at or adjacent its middle to said first bracket ; a second bracket having one end pivotally connected to the chassis on one side of said first bracket and having its other end pivotally connected to one end of leaf spring, with the other end of said leaf spring being connected to the chassis on the other side of said first bracket; and a shock absorber being connected between the first bracket and the chassis adjacent the said second bracket. 2. A wheel assembly according to claim 1 , wherein the trailing arm is pivoted on a shaft connected to the arm of the chassis, and the free end of the shaft is engaged and supported by a support plate, which is fixedly attached to a reinforcing strut extending from the chassis arm. 3. A vehicle comprising a tray having posts parallel to each other extending from the tray; a yoke or u-shaped chassis having side walls extending substantially normal to the plane of the chassis; parallel elongated members located in said side walls and telescopingly engaging with said parallel posts of said tray so as to enhance the rigidity of the chassis and to maintain the tray in a substantially the same orientation during the movement of the tray from a raised transport position to a ground engaging loading position; drive means to move said tray between said transport position and said loading position; and a wheel assembly located on each arm of the chassis, comprising: a trailing arm pivotally suspended from a first end to one ami of the chassis; a wheel stub axle mounting located at or adjacent the free end of the trailing arm; a connection means located on said trailing arm adjacent said wheel stub axle mounting; a first bracket pivotally connected to said connection means of said trailing arm; a leaf spring connected at or adjacent its middle to said first bracket ; a second bracket having one end pivotally connected to the arm of the chassis on one side of said first bracket and having its other end pivotally connected to one end of leaf spring, with the other end of said leaf spring being connected to the arm of the chassis on the other side of said first bracket; and a shock absorber being connected between the first bracket and the arm of the chassis adjacent the said second bracket. 4. A vehicle according to claim 3 wherein each arm of the chassis is stepped to form a lower front portion and a higher back portion, with the first end of the trailing arm being pivotally connected to the lower front portion of the arm of the chassis, and the second bracket is connected to the higher back portion of the arm of the chassis. 5. A vehicle according to claim 4, wherein the trailing arm is pivoted on a shaft connected to the lower portion of the arm of the chassis, and the free end of the shaft is engaged and supported by a support plate, which is fixedly attached to a reinforcing strut extending from the lower portion of the chassis arm. 6. A vehicle according to claim 5, wherein the chassis comprises two opposed side walls and an end wall, each of which include a top and bottom rail, joined by reinforcing struts, and the drive means is located adjacent the four corners of the chassis. 7. A vehicle according to any one of claims 3 to 6, wherein the drive means comprises a worm drive. 8. A vehicle according to any one of claims 3 to 6, wherein the drive means comprises four hydraulic cylinders, each located adjacent a respective corner of the chassis and having their cylinder rod passing through the respective bottom rails of the chassis. 9. A Wheel assembly substantially as herein before described with reference to figures 5 to 9 of the accompanying drawings. 10. A vehicle substantially as herein before described with reference to the accompanying drawings.

Inventors: SOBINA ROMAN, SOBINA, ROMAN
Applicants: SOBINA ROMAN, THANKSMATE PTY LTD, SOBINA, ROMAN, THANKSMATE PTY. LTD.
Application year: 1995
Main classification: B60G3
IPC codes: B60G3, B60G11, B60G15