GB1579411A

GB1579411A - Trailers

Info

Publication number: GB1579411A
Application number: GB737278A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-02-23
Filing date: 1978-02-23
Publication date: 1980-11-19

Description

(54) TRAILERS (71) I BARRY PRICE of Plantation Mill, Flip Road, Haslingden, in the county of Lancaster, a British Subject, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to trailers.

The invention provides a trailer comprising an elongate body having a load carrying platform, the front end of the body being arranged for attachment to a towing vehicle and the rear end having a wheeled suspension unit for supporting the trailer, the suspension unit having at least two wheeled axles spaced apart in the direction of the longitudinal axis of the body, the suspension unit being releasably secured to the rear end of the body such that after the suspension unit has been released from the rear end of the body, the trailer body may be moved backwardly over the suspension unit, the body tilting progressively downwardly towards the rear end as the suspension unit approaches the front of the body, until the angle of tilt is such that the load carrying platform is accessible from ground level at the rear end of the body.

Preferably each axle is slung over a spring of the suspension unit, to reduce the height of the suspension unit.

The springs are preferably leaf springs.

The front of the elongate body preferably comprises a continuation of the load carrying platform, which, in use, will extend over the rear end of the towing vehicle, the underside of the continuation having a coupling projecting downwardly therefrom, for connection to the towing vehicle.

Preferably the trailer body is arranged to slide over the suspension unit.

The trailer body may have a pair of elongate parallel support members, each sliding in a channel on the suspension unit.

There may be a set of rollers arranged in the bottom of each of the channels to facilitate sliding of the elongate support members.

The channels may each be formed by welding said plates to an elongate member of the suspension unit.

Preferably the rollers are removable for replacement or repair.

The suspension unit may be releasably secured to the rear end of the trailer body by one or more locking pins.

There may be a locking pin at each side of the trailer body, the pins being interconnected by a lever and linkage arranged to provide simultaneous movement of the pins.

There may be at least one spigot and socket interconnection between the suspension unit and the rear end of the trailer body, the axis of the spigot and socket extending longitudinally of the trailer to restrain relative movement between the trailer body and the suspension unit in the vertical direction when the suspension unit is secured to the rear end of the trailer body, the spigot entering the socket as the suspension unit approaches the rear end of the trailer.

Preferably there is a spigot at each side of the suspension unit and a co-operating socket member arranged at each side of the rear end of the trailer body.

There may be one or more support wheels or rollers on the underside of the rear end of the trailer body to support the rear end of the trailer body when it is lowered by backward movement of the trailer body over the suspension unit.

The trailer may have a hinged tail-board which, when the rear end of the trailer body has been lowered, can be used as a ramp to enable a vehicle to drive up the tailboard and on to the load carrying platform.

The trailer may have one or more support legs at the rear end of the trailer body, which legs can be lowered into contact with the ground.

By way of example, a specific embodiment of trailer according to the invention will now be described, with reference to the accompanying drawings, in which: Figure 1 is a side view of an embodiment of trailer according to the invention, with the suspension unit arranged at the rear end of the trailer; Figure 2 is a side view of the trailer showing the suspension unit at the front end of the trailer, with the body of the trailer tilted downwarldly towards the rear end of the trailer; Figure 3 is a side view of the suspension unit, with the wheels of the suspension unit removed for the sake of clarity; Figure 4 is a plan view of the suspension unit shown in Figure 3; Figure 5 is an end view of the suspension unit shown in Figure 3; and Figure 6 is a cross-section through one of the rollers of the suspension unit.

The trailer shown in Figures 1 and 2 has an elongate body 10, the upper surface of which provides a flat load carrying platform 11. At the front end of the trailer there is arranged a conventional device 12 for coupling the trailer to a towing vehicle, and there are also arranged a pair of extendable support legs 13 for use in supporting the front end of the trailer when the trailer is parked without the towing vehicle in position.

The trailer is supported by a suspension unit 14 which has a pair of parallel axes 15 (see Figures 3 to 5) spaced apart in the direction of the longitudinal axis of the body, there being a road wheel 16 arranged at each end of each axle.

When the trailer is being utilised normally, the suspension unit 14 is secured to the body of the trailer at the rear end of the trailer, as shown in Figure 1, and the trailer operates in a conventional manner.

If however it is desired to gain access to the load platform 11 from the ground level 17, the suspension unit 14 can be disconnected from the trailer body 10. Air hoses (not shown) connected to the brakes (not shown) of the suspension unit 14 are also disconnected, and this causes the brakes automatically to lock on. The suspension unit 14 therefore remains stationary but the towing vehicle can be used to reverse the trailer so that the trailer rolls backwardly over the suspension unit 14, until the suspension unit reaches the front end of the trailer as shown in Figure 2. Displacement of the suspension unit from underneath the rear end of the trailer causes the trailer to tilt progressively towards the rear end and when the position shown in Figure 2 is reached, the rear end of the load platform 11 is readily accessible from ground level.

Conventional trailers only have a crash bar at the rear end but the rear end of the trailer body 10 has a hinged tail-board 18 which not only fulfills the function of a crash bar but can also be swung into a position in which it bridges the slight gap between ground level 17 and the load platform 11 forming a ramp so that a vehicle can drive on to the load platform 11. This means that not only can other vehicles such as forklift trucks be used to load goods on to the load platform, but it also means that the trailer piggyback manner. In fact a trailer similar can be used to carry other vehicles in a in length to that shown in Figures 1 and 2, together with its towing vehicle, can be accommodated on top of the trailer shown in Figures 1 and 2. The ability to load one vehicle on top of another very rapidly at any location represents a considerable improvement over existing arrangements, where it is necessary for vehicles to travel to a location where there is a loading ramp of appropriate dimensions, before one vehicle can drive on to the load platform of another vehicle.

The details of the suspension unit will now be described with reference to Figures 3 to 6. The suspension unit has a generally rectangular upper part comprising two elongate side members 19 and 20, between which are welded two end members 21 and 22.

To each end of each side member 20 a pair of vertically extending plates 23 are welded.

The lower ends of these plates are provided with supports for one end of each of a set of suspension springs 24. The upper ends of the plate 23 define a channel 25 as best shown in Figure 5.

The other ends of the springs 24 are supported by trunnion plates 26 welded to each side of the central portion of each side member 19 and 20. The upper ends of the trunnion plates 26 project above the members 19 and 20 to assist in defining the channels 25. Each of the axles 15 is slung over one of the springs 24. The suspension unit has a conventional brake air tank and conventional brakes for the wheels, but as these parts are conventional and are not inventive in themselves, they will not be described in detail.

In each of the channels 25 lies a set of six rollers 27. The rollers have parallel axes which extend across the channels, and the rollers are spaced apart along the length of the channels.

Each of the side members 19 and 20 comprises a channel member having upstanding side walls, and each roller is secured in position by a bolt 28 which passes through one of the walls of the channel, then through the roller, then through the other wall of the channel, and is then sec ured in position by a nut 29.

Figure 6 is a cross-section, to a larger scale, through one of the rollers 27. Each roller is of steel, lined with a brass bush 30.

The shank of the bolt 28 is also of steel.

At the rear end of each of the side members 19 and 20 there is a spigot 31 having a tapered nose.

The trailer body 10 has a pair of elongate support members 32 on its underside.

Each of these support members comprises a metal girder, the dimensions being such that each girder fits into one of the channels 25 and rests on one of the sets of rollers 27. Welded to the underside of each support member 32 at the rear end of the trailer, is a socket member 33. Each socket member co-operates with one of the spigots 31 and the socket members are shown in Figures 3 and 4. The spigots 31 extend parallel to the longitudinal axis of the vehicle and each socket 34 of the socket members 33 is aligned with the associated spigot so that when the suspension unit moves towards the rear of the trailer body the spigots 31 engage in the sockets 34 to prevent relative vertical movement between the suspension unit and the trailer.

At the front end of each support member 32 a block 35 is welded to limit the forward movement of the suspension unit 14 with respect to the trailer body. The limit of forward movement is reached when the front ends of the side members 19 and 20 butt against the blocks 35.

When the suspension unit is in the position shown in Figure 1, it can be releasably secured to the trailer body by a pair of locking pins (not shown), which pass through holes 36 in the front plates 23 and into holes in the support members 32 of the trailer body. If desired, to facilitate rapid operation of these pins, each pin may be connected by a link to a lever pivoted on the member 22. The two pins are connected to the lever on opposite sides of its pivot respectively, so that pivotal movement of the lever in one direction causes simultaneous withdrawal of the locking pins and pivotal movement in the opposite direction causes simultaneous insertion of the pins. The lever may be connected to a single operating handle and there may be means to lock the handle in the position in which the locking pins are inserted.

The arrangement shown in the Figures provides for extremely rapid operation, enabling tilting of the load platform substantially to ground level without the need to uncouple the towing vehicle or utilise any complicated hydraulic or electrical jacking system. It is only necessary to release the locking pins and uncouple the brake hoses, operations which can be carried out in a matter of seconds, and then the towing vehicle is simply put into reverse for the necessary distance.

The invention is not restricted to the details of the foregoing embodiment. For instance a pair of small support wheels or a support roller may be provided on the underside of the support members 32 at the rear end of the trailer body, at the point indicated by the reference numeral 37, since under certain loading conditions this point of the trailer may tend to actually contact the ground when the suspension unit is at the front of the trailer. Similarly a pair of small wheels or a roller may be provided at the free edge 38 of the tail-board 18.

Alternatively, or in addition, a pair of adjustable support legs may be provided at the rear end of the trailer body.

Not only may completely new trailers be manufactured having the form of the above described embodiment, but existing trailers may also be converted into trailers according to the invention by removing their existing suspension unit, replacing it with a suspension unit as shown in Figures 3 to 6, and welding the socket members 33 and the blocks 35 to the support members 32 of the existing trailer.

WHAT WE CLAIM IS: 1. A trailer comprising an elongate body having a load carrying platform, the front end of the body being arranged for attachment to a towing vehicle and the rear end having a wheeled suspension unit for supporting the trailer, the suspension unit having at least two wheeled axles spaced apart in the direction of the longitudinal axis of the body, the suspension unit being releasably secured to the rear end of the body such that after the suspension unit has been released from the rear end of the body, the trailer body may be moved backwardly over the suspension unit, the body tilting progressively downwardly towards the rear end as the suspension unit approaches the front of the body, until the angle of tilt is such that the load carrying platform is accessible from ground level at the rear end of the body.

2. A trailer as claimed in Claim 1, in which each axle is slung over a spring of the suspension unit, to reduce the height of the suspension unit.

3. A trailer as claimed in Claim 2, in which the springs are leaf springs.

4. A trailer as claimed in any one of the preceding claims, in which the front end of the elongate body comprises a continuation of the load carrying platform, which, in use, extends over the towing vehicle, the underside of the continuation having a coupling projecting downwardly therefrom, for connection to the towing

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ured in position by a nut 29. Figure 6 is a cross-section, to a larger scale, through one of the rollers 27. Each roller is of steel, lined with a brass bush 30. The shank of the bolt 28 is also of steel. At the rear end of each of the side members 19 and 20 there is a spigot 31 having a tapered nose. The trailer body 10 has a pair of elongate support members 32 on its underside. Each of these support members comprises a metal girder, the dimensions being such that each girder fits into one of the channels 25 and rests on one of the sets of rollers 27. Welded to the underside of each support member 32 at the rear end of the trailer, is a socket member 33. Each socket member co-operates with one of the spigots 31 and the socket members are shown in Figures 3 and 4. The spigots 31 extend parallel to the longitudinal axis of the vehicle and each socket 34 of the socket members 33 is aligned with the associated spigot so that when the suspension unit moves towards the rear of the trailer body the spigots 31 engage in the sockets 34 to prevent relative vertical movement between the suspension unit and the trailer. At the front end of each support member 32 a block 35 is welded to limit the forward movement of the suspension unit 14 with respect to the trailer body. The limit of forward movement is reached when the front ends of the side members 19 and 20 butt against the blocks 35. When the suspension unit is in the position shown in Figure 1, it can be releasably secured to the trailer body by a pair of locking pins (not shown), which pass through holes 36 in the front plates 23 and into holes in the support members 32 of the trailer body. If desired, to facilitate rapid operation of these pins, each pin may be connected by a link to a lever pivoted on the member 22. The two pins are connected to the lever on opposite sides of its pivot respectively, so that pivotal movement of the lever in one direction causes simultaneous withdrawal of the locking pins and pivotal movement in the opposite direction causes simultaneous insertion of the pins. The lever may be connected to a single operating handle and there may be means to lock the handle in the position in which the locking pins are inserted. The arrangement shown in the Figures provides for extremely rapid operation, enabling tilting of the load platform substantially to ground level without the need to uncouple the towing vehicle or utilise any complicated hydraulic or electrical jacking system. It is only necessary to release the locking pins and uncouple the brake hoses, operations which can be carried out in a matter of seconds, and then the towing vehicle is simply put into reverse for the necessary distance. The invention is not restricted to the details of the foregoing embodiment. For instance a pair of small support wheels or a support roller may be provided on the underside of the support members 32 at the rear end of the trailer body, at the point indicated by the reference numeral 37, since under certain loading conditions this point of the trailer may tend to actually contact the ground when the suspension unit is at the front of the trailer. Similarly a pair of small wheels or a roller may be provided at the free edge 38 of the tail-board 18. Alternatively, or in addition, a pair of adjustable support legs may be provided at the rear end of the trailer body. Not only may completely new trailers be manufactured having the form of the above described embodiment, but existing trailers may also be converted into trailers according to the invention by removing their existing suspension unit, replacing it with a suspension unit as shown in Figures 3 to 6, and welding the socket members 33 and the blocks 35 to the support members 32 of the existing trailer. WHAT WE CLAIM IS:

1. A trailer comprising an elongate body having a load carrying platform, the front end of the body being arranged for attachment to a towing vehicle and the rear end having a wheeled suspension unit for supporting the trailer, the suspension unit having at least two wheeled axles spaced apart in the direction of the longitudinal axis of the body, the suspension unit being releasably secured to the rear end of the body such that after the suspension unit has been released from the rear end of the body, the trailer body may be moved backwardly over the suspension unit, the body tilting progressively downwardly towards the rear end as the suspension unit approaches the front of the body, until the angle of tilt is such that the load carrying platform is accessible from ground level at the rear end of the body.

3. A trailer as claimed in Claim 2, in which the springs are leaf springs.

vehicle.

5. A trailer as claimed in any one of the preceding claims, in which the trailer body is arranged to slide over the suspension unit.

6. A trailer as claimed in Claim 5, in which the trailer body has a pair of elongate parallel support members, each sliding in a channel on the suspension unit.

7. A trailer as claimed in Claim 6, in which there is a set of rollers arranged in the bottom of each of the channels, to facilitate sliding of the elongate support members in the channels.

8. A trailer as claimed in Claim 7, in which the channels are each formed by welding side plates to an elongate member of the suspension unit.

9. A trailer as claimed in Claim 7 or Claim 8, in which the rollers are removable for replacement or repair.

10. A trailer as claimed in any one of the preceding claims, in which the suspension unit is releasably secured to the rear end of the trailer body by one or more locking pins.

11. A trailer as claimed in Claim 10, in which there is a locking pin at each side of the trailer body, the pins being interconnected by a lever and linkage arranged to provide simultaneous movement of the pins.

12. A trailer as claimed in any one of the preceding claims, in which there is at least one spigot and socket interconnection between the suspension unit and the rear end of the trailer body, the axis of the spigot and socket extending longitudinally of the trailer to restrain relative movement between the trailer body and the suspension unit in the vertical direction when the suspension unit is secured to the rear end of the trailer body, the spigot entering the socket as the suspension unit approaches the rear end of the trailer.

13. A trailer as claimed in Claim 12, in which there is a spigot at each side of the suspension unit and a co-operating socket member arranged at each side of the rear end of the trailer body.

14. A trailer as claimed in any one of the preceding claims, in which there is one or more support wheels or rollers on the underside of the rear end of the trailer body to support the rear end of the trailer body when it is lowered by backward movement of the trailer body over the suspension unit.

15. A trailer as claimed in any one of the preceding claims, having a tail-board which is pivotally connected to the trailer body so that when the rear end of the trailer body is in the lowered position the tail-board can be arranged to bridge any gap between the ground and the load carrying platform to enable a vehicle to drive up the tail-board and on to the load carrying platform.

16. A trailer as claimed in any one of the preceding claims, having one or more support legs at the rear end of the trailer body, which legs can be lowered into contact with the ground.

17. A trailer constructed and arranged substantially as hereinbefore described, with reference to the accompanying drawings.