GB2332930A

GB2332930A - Wheel chock device

Info

Publication number: GB2332930A
Application number: GB9823938A
Authority: GB
Inventors: Michael Allan Freeman
Original assignee: Turpins PLC
Current assignee: Turpins PLC
Priority date: 1997-11-04
Filing date: 1998-11-03
Publication date: 1999-07-07
Anticipated expiration: 2018-11-03
Also published as: GB9823938D0; GB9723153D0; GB2332930B

Abstract

A wheel chock device is constructed of three or more mutually hinged sections, each made up of spaced bars 10, 12, 14; 16, 18; 20, 22, 24. Adjustable tongues 32, 34 engage behind tube 36 to retain the device in its triangular configuration. Alternatively, the bars may be of channel-section, in which case, the ends of the bars 20, 22, 24 drop into the open-topped channels of bars 10, 12, 14 and lodge behind the tube 36. The chock device can be folded into a compact form for storage (Fig. 1) or for supporting a jack between lips (45, 47 Fig. 1), or can be stretched out in one plane to act as a sand ladder (Fig.4). The bars may be made of aluminium or stainless steel.

Description

WHEEL CHOCK DEVICE This invention relates to a wheel chock for chocking the wheels of a vehicle. Vehicle wheels have to be chocked in a number of different situations. For example, when one side of a car is jacked up to change a wheel, it is always recommended that one or both wheels on the opposite side be chocked to ensure that the vehicle does not roll forward or backwards whilst part of it is being supported other than on its wheels. Wheel chocking becomes even more important with the use of off-road vehicles, where it is often necessary to raise part of a vehicle off the ground in order to extricate the wheels from a place where they have no grip or to raise the vehicle sufficiently for it to pass over an obstacle or for an obstacle to passed underneath the vehicle.

Whilst a piece of brick or the like is generally adequate to chock the wheels of a car on a road or other level surface, an off-road vehicle travelling over rough terrain needs a much more substantial chock.

It has been common practice for off-road vehicles to carry around with them one or more chocks, against a situation when they will be needed. Such chocks are rigid triangular shaped bodies which are heavy and take up a lot of space. As a result, they are not always carried when they should be carried and this can lead to difficulties.

According to the invention, there is provided a wheel chock device for chocking the wheels of a vehicle, the device comprising at least three sections hinged to one another about spaced-apart parallel axes, each section being formed from a set of spaced bars, the sections being adapted to be turned about the parallel hinged axes to form a triangular body and means for securing the sect ions in the form of a triangular body.

The use of three hinged sections allows the device to be turned about the parallel hinged axes so as to take up a compact, folded configuration in which it can be readily stored without taking up excess space.

The use of three hinged sections also allows the device to have a secondary function, as a so-called sand ladder.

If the sections are laid out so that they lie end to end, an elongate surface is formed which can be laid over unstable ground, so that a vehicle wheel can ride over that unstable ground, on the surface of the device.

The spaced bars which form the chock device may be square section bars made of hollow bar stock, with the ends of each bar section being closed. One face of each bar section can be provided with surface irregularities, such as ribs, to provide grip when a vehicle wheel is in contact with that surface.

Alternatively the bars may be made from channel section stock, so that the bars have one open face. The surface irregularities can be formed by plunged holes in the outward facing face of the channel section. The holes may have raised rims.

The beams preferably are arranged parallel to one another and the beams in each section are spaced apart so that when the device is folded, beams of adjacent sections can lie between one another to reduce the overall size of the folded device.

The beams may be made from aluminium or steel (preferably stainless steel) channel or square section stock.

It is possible to have more than three sections, when a longer sand ladder is required. Normally however when the device is erected into its chocking configuration, only three sections are likely to take part, namely one section lying on the ground, one section forming the abutment surface for the vehicle wheel and one section bracing the abutment surface against the ground engaging surface.

The hinging between the sections is preferably accomplished by a round bar or tube which is fitted through aligned drilled holes through the ends of the adjoining and overlapping sections.

The device can have a third function, as a jacking base.

When folded, the device preferably has two opposite substantially parallel faces. One face preferably has a lip or lips around a support area which will accommodate the foot of a jack. The device can be placed on the ground at the place where the jack is to be used, the jack foot is placed in the support area, and the jack is operated to raise a load. Placing the jack foot on the device spreads the ground loading arising from jack operation over an area substantially larger than that of the jack foot.

When folded, the device preferably has one of its parallel faces substantially larger than the opposite face, and the smaller of the two faces carries the support area.

The invention will now be further described by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a wheel chock device in accordance with the invention in its folded away configuration; Figure 2 shows the device of Figure 1 in its folded configuration as shown in Figure 1 but turned over; Figure 3 shows the device of Figures 1 and 2 erected to act as a chock; and Figure 4 shows the device unfolded and in use as a sand ladder lying on irregular ground.

Figure 1 shows a three-section chock device in a folded configuration. The first chock section is represented by bars 10,12 and 14; the second section is represented by bars 16 and 18 and the third section is represented by bars 20,22 and 24. The first section is hinged to the second section by a tube 26 which forms a hinge axis and the second section is hinged to the third section by a similar tube 28. A third tube 36 connects the free ends of the bars 10,12,14.

The bars shown are formed from square section stock. The bars can however alternatively be formed from channel section stock. Square section stock is preferred, because the device will usually be used in a dirty environment, and it is easier to clean and remove dirt from closed section bars than open section bars.

The bars 10,12,14,16,18,20,22 and 24 all carry external ribbed strips 39 on at least one face. These strips provided with ribs 40 are present to provide surface roughness to enhance the grip of a tyre on the bars and/or to enhance the grip of the device on the ground. Many different formations could be provided on the surfaces of the bars. Ribs may be formed by applying material to the surface of the bars as shown, or by deforming the bar surfaces as desired. In the embodiments shown, the strips 39 are riveted in place.

It is alternatively possible to pierce the bar walls and to locally raise the material of the wall to provide the surface roughness. This is particularly easy to do if the bars are formed from channel section but does have the disadvantage that dirt penetrates easily into the section and is then difficult to remove.

Figure 3 shows the device erected as a wheel chock and with the three sections forming a generally equilateral triangle. In this position, the first chock section 10,12,14 will be placed on the ground; the second section 16,18 will be placed in front of (or behind) a wheel to be chocked with the load on this section being applied in the direction of an arrow 30 and the third section 20,22,24 supports the top end of the second section against the ground and/or against the first section.

In order for the third section 20,22,24 to do this, it has a pair of tongues 32,34 which project beyond the ends of the bars 20,22,24, lodge behind the parts of the third tube 36 which are exposed between the ends of the bars 20,22,24 (as shown in Figure 3) and which are long enough to extend down below the bottom surface of the bars 10,12,14 so that they dig into the ground. As a result of this, when a force is applied to the second section as indicated by the arrow 30, the tongues will be pressed against the tube 36 and into the ground, and the bars 20,22,24 will be put into compression.

The extent to which the tongues 32,34 project beyond the ends of the bars 20,22,24 can be changed, depending on the nature of the ground on which the device is used. The tongues are secured to a cross member 33 (Figure 3) by bolts 37 which screw into tapped holes in the tongues 32,34. The tongues are provided with a range of tapped holes, as can be seen at 42 and the bolts 37 can be screwed into a selected set of these holes to determine the extent of projection of the tongues.

The cross bar 33 extends the full width of the device and fits through correspondingly shaped slots in the side walls of the bars 20,22,24.

The tubes 26,28 and 36 can be held in place by rivets 35 extending through the adjacent walls of the bars, as shown in Figure 3.

The tongues 32,34 can be of channel section material, to be strong enough to resist the wear and the bending loads to which they will be subjected.

Normally, the chock will be erected and positioned relative to a vehicle wheel with the ends of the tongues 32,34 sitting on the ground surface, As the weight of the vehicle is applied in the direction of arrow 30, a force will be applied through the bars 16,18 and the tube 28 to the bars 20,22,24 and to the tongues 32,34. This force will have a component acting on the tongues tending to dig them into the ground.

In an alternative construction which is not shown in the drawings, the bars could be of channel section, with the open faces of the bars facing inwards, so that the lower ends of the bars 20,22,24 could drop into the open-topped channels of the bars 10,12,and 14 so that they lodge behind the tube 36.

Figure 1 shows how the reverse side of the third section 20,22,24 provides a support area for the foot of a lifting jack. A dotted line indicates the area of a typical jack foot which can be placed on the device in the position shown, where it is retained by lips 45,47. The lips 45 are formed by upstanding parts of the tongues 32,34 and the lips 47 are formed by riveted-on plates 49. With the device in this orientation, the larger area first section of the device is in contact with the ground, to enlarge the load bearing area when the jack is in use. This helps to prevent the jack base from sinking into the ground, when under load.

No lock or latch mechanism is required; the erect condition of the chock will automatically hold itself in position when a force is applied, whether or not the tongues 32,34 dig into the ground. It will be noted that the bars 10,12,14 extend in the direction from which the force 30 is being applied, beyond the position of the hinge tube 26. This allows a vehicle wheel to first apply a downward force on the device before acting against the bars 16,18 so that the device does not skid away in front of the vehicle wheel.

Figure 4 shows the device laid out along an uneven surface, with the hinges at 26 and 28 allowing the sections to follow the surface contours. In this configuration, the chock has its second application, to provide a firm surface for a vehicle wheel to obtain sufficient traction to drive out of a patch of loose ground.

In use, the device will be stored in a vehicle in its compact folded down condition as shown in Figures 1 and 2.

When a wheel of the vehicle is to be chocked, the chock will be unfolded by lifting and turning anticlockwise the third section 20,22,24 about the hinge 28. In so doing the second section will also be turned (clockwise) about the hinge 26. The references to clockwise and anticlockwise are referred to the specific orientation of the chock as shown in Figure 1. The tongues 32, 34 will be inserted between the bars 10,12,14 to retain the chock in a triangular configuration, and tle chock can then be positioned against a wheel of the vehicle and used to prevent the vehicle moving. After use, the chock can be easily refolded to the configuration shown in Figure 1.

If the vehicle becomes stuck, for example in loose sand, or on snow or ice, the device can be used in another configuration. The sections will be laid out in line on the ground in front of a driven wheel of the vehicle, and once the wheel achieves frictional contact with the top surface of the first of the sections, it can be driven over the whole length of the device, with the friction between the device and the ground being sufficient to ensure that the device does not move relative to the ground while the vehicle moves relative to the device.

As the vehicle moves over the device, the sections will hinge relative to one another in accordance with the degree of support provided by the ground, and this will allow the device to follow the ground contours. It is a disadvantage of conventional rigid sand ladders that they tend to take up a bowed shape after use, because they cannot flex to follow the contours over which they are being used.

The invention thus provides a multi-purpose device for use with motor vehicles, particularly off-road vehicles, which in addition to its multi-purpose nature has advantages over both existing chocks and existing sand ladders as a result of its hinged sections.

By making the bars from hollow light weight material, such as aluminium or an alloy of aluminium or small section steel, the device can have a low overall weight whilst being able to fold up into a small space.

Claims

Claims 1. A wheel chock device for chocking the wheels of a vehicle, the device comprising at least three sections hinged to one another about spaced-apart parallel axes, each section being formed from a set of spaced bars, the sections being adapted to be turned about the parallel hinged axes to form a triangular body and means for securing the sections in the form of a triangular body.
2. A device as claimed in Claim 1, which has a secondary function, as a so-called 'sand ladder'.
3. A device as claimed in Claim 1 or Claim 2, which has a tertiary function, as a so-called 'jacking base'.
4. A device as claimed in any preceding claim, wherein the spaced bars which form the chock device are square section bars made of hollow bar stock.
5. A device as claimed in Claim 3, wherein the ends of each bar are closed.
6. A device as claimed in any preceding claim, wherein at least one face of each bar is provided with surface irregularities to provide grip when a vehicle wheel is in contact with that surface or when the surface is in contact with another surface.
7. A device as claimed in any preceding claim, wherein the bars are arranged parallel to one another and the bars in each section are spaced apart so that when the device is folded, bars of adjacent sections can lie between one another to reduce the overall size of the folded device.
8. A device as claimed in Claim 6, wherein the bars forming one section are provided with a through hole, the bars forming another section are also provided with a through hole, the ends of the bars of two adjacent sections are introduced between each other so that their through holes line up, a round bar or tube is fitted through the through holes and is secured in place to form a hinge axis about which the sections can be relatively rotated.
9. A device as claimed in any preceding claim, wherein the bars are made from aluminium or an aluminium alloy.
10. A device as claimed in any preceding claim, wherein the means for securing the sections in the form of a triangular body comprises tongues extending from the nonhinged end of one of the sections and adapted to pass between the bars of the other non-hinged end, and a crossbar at said other non-hinged end extending between the section bars to locate the tongues within the triangular body.
11. A device as claimed in Claim 10, wherein the said non-hinged end has bars which make contact with the bars of the other non-hinged end, and the length of the tongues is such that they extend beyond the triangular form of the device, when there is contact between the section bars of the non-hinged ends.
12. A device as claimed in Claim 10 or Claim 11, wherein the extent by which the tongues extend from the non-hinged end can be adjusted.
13. A device as claimed in any preceding claim wherein there are more than three sections.
14. A chocking device substantially as herein described with reference to the accompanying drawings.