GB1598697A

GB1598697A - Tipping vehicles

Info

Publication number: GB1598697A
Application number: GB1748477A
Authority: GB
Original assignee: TRIGG B
Current assignee: TRIGG B
Priority date: 1977-04-27
Filing date: 1977-04-27
Publication date: 1981-09-23
Also published as: FR2388695A1; DE2817637A1

Description

(54) IMPROVEMENTS IN OR RELATING TO TIPPING VEHICLES (71) I, BRIAN TRIGG, a British Subject, of Greenwood Falls Farm, Mill Lane, Huthwaite, Sutton-in-Ashfield, Nottinghamshire, 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 present invention concerns improvements in or relating to vehicles including a tipping load platform, especially, but not exlusively to tipping trailers.

Certain tipping vehicles are available wherein the load carrying platform is raised when it is tipped about an axis transverse to the longitudinal axis of the vehicle. In certain instances, especially with articulated vehicles or with trailers, this results in a "vertical jack-knifing" caused by the transference of load over or beyond the rear axle of the vehicle, this transference resulting in the front end of the vehicle tending to move upwardly.

Various means have been adopted in the past in an attempt to obviate this vertical jack-knifing, ranging from the crudest, which is simply a ground-engaging stop at the rear end of the vehicle, to complicated and expensive arrangements of hydraulic rams, linkages and the like.

A further disadvantage of certain high-lift tipping vehicles is that it is not possible to use them in a normal low tipping manner.

It is an object of the present invention to obviate or mitigate the disadvantages of previous tipping vehicles.

According to the present invention there is provided a vehicle including a chassis, ground engaging means carried by a frame pivotally mounted to and below the chassis about a transverse axis thereof at or near one end of the chassis, a load platform pivotally mounted about a transverse axis at one end of it's base to the chassis at or near said one end and operating means connected between said chassis and said frame and said chassis and said platform operable to pivot said frame and said platform about said axis, said frame being arranged such that movement of the ground engaging means thereon away from said chassis causes movement of the said means in the direction of the said one end of the chassis.

Preferably said operating means includes a linkage connected between said platform and said ground engaging means in such a manner that with the ends of certain links of said linkage optionally constrained to move in a fixed path relative to said chassis, when said platform pivots said frame pivots relative to the chassis.

Preferably said linkage is pivotally connected to said chassis at one point, to said load platform at another point, to said ground engaging means at a further point, and is capable of being constrained to move in a fixed path relative to said chassis at a still further point.

Preferably said linkage is a parallelogram linkage.

Preferably said means for constraining said further point to move in a fixed path relative .to said chassis comprises roller means on said still further linkage point engaged in a channel formed in or carried by said chassis.

Preferably actuating means are connected between said chassis and said still further linkage point.

Preferably a. steadying strut is pivotally mounted between said ground engaging means and said chassis to retain said groundengaging means in a fixed orientation irrespective of the orientation of the chassis.

Preferably said actuating means comprise a hydraulic ram.

In an alternative arrangement the two links of said linkage which meet at said still further point are independent of each other and are each independently constrainable relative to the chassis, actuating means, preferably in the form of a hydraulic ram, being associated with each of said links.

Preferably each link comprises a rigid framework extending transversely of the longitudinal axis of the chassis.

Preferably said ground engaging means comprise an axle carrying a wheel at each end but alternatively it may comprise a bogey including tandem axles each carrying at least one pair of wheels, or a bogey fitted with ground engaging skids or crawler tracks.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Fig. 1 shows diagrammatically a trailer with its load carrying platform in a high-lift tipped position; Fig. 2 is a more detailed and elevation of a component of the trailer of Fig. 1; Fig. 3 shows diagrammatically the trailer of Fig. 1 with the load carrying platform approaching its normal rest position; Fig. 4 shows the trailer of Fig. 1 being operated in a modified manner; and Figs. 5 and 6 show diagrammatically modified trailers in the high-lift tipped position.

Figs. 7 to 9, show in line diagrams further modified trailers.

A trailer comprises a chassis 10 fitted with a tow-bar 11 at its front for hitching to a tractor or the like and a load carrying platform 12, pivotally mounted on the chassis 10 about an axis 14 running transversely of the longitudinal axis of the chassis. The trailer is provided with a pair of ground engaging wheels 16, only one of which is shown.

A parellelogram linkage is connected with the platform 12, the chassis 10 and wheel carrying member 18, the linkage comprising three similar frames 20 (Fig. 2) each comprising two main members 22 and two cross struts 24. A first frame 20a is pivotally connected between the load platform 12 and a block 26, the block 26 having one end of a second frame 20b pivotally connected thereto, the other end of the frame 20b being pivotally connected to the wheel carrying member 18. A third frame 20c is pivotally connected to the wheel carrying member 18 and to the chassis 10. The fourth link of the parallelogram linkage is constituted by the load carrying platform 12.

Means, not shown, are provided for constraining the block 26 to move along the longitudinal direction of the chassis 10, said means comprising roller members on the block 26 accommodated in guideways fixed to the chassis.

A pair of telescopic hydraulic rams 27 are arranged in side-by-side relationship and are each attached at one end to the block 26 and at the other end to the chassis adjacent the front thereof.

To ensure that the wheel carrying member 18 maintains the same orientation during movement of the various components of the linkage, the chassis and the load carrying platform, a steady strut 30 is pivotally connected between the member 18 and the chassis 10.

Fig. 3 shows the trailer with the hydraulic ram 27 almost fully retracted and the load carrying platform just about to engage a support stop 32, fixed to the chassis 10. It should be noticed that in this condition the wheels 16 carried by the member 18 are positioned towards the front of the trailer, in other words close to the centre of gravity of the load.

When it is desired to tip the trailer hydraulic fluid is supplied to the rams 27 which extend and push the blocks 26 along the guideways in the chassis 10, this movement actuating the linkage and this in turn serving two purposes, firstly to pivot the platform 12 relative to the chassis 10 and secondly to move the wheels downwardly and rearwardly relative to the chassis until the position shown in Fig. 1 is reached, in practice the chassis being raised relative to the ground so that the tail gate of the load carrying platform is raised well above the ground, a position desired in several operations. It should be noticed that in the position the wheels 16 have moved towards the rear of the trailer, following the position of the line of action of the centre of gravity of the load.

As a result, at all stages during the tipping operation the wheels are positioned under or fairly close to the line of action of the centre of gravity of the load so that there is little or not turning moment about the wheels and the tendency to vertical Jack-knife is considerably reduced, if not eliminated.

In a first modification of the arrangement described above means are provided for disengaging the blocks 26 from the guideways on the chassis 10. When the blocks 26 are thus disengaged the trailer can be tipped in the normal manner as shown in Fig. 4, and on extension of the rams 27 the wheels remain in the same position relative to the chassis and the blocks 26 move upwardly away from the chassis.

Fig. 5 shows a further modified trailer in the tipped condition. The trailer shown in Fig. 5 includes most of the components of the trailer shown in Fig. 1 and these have been given similar reference numerals. The blocks 26 of the Fig. 1 embodiment are dispensed with however, and two blocks 26a and 26b are provided, each movable in its own guideway (not shown).

Each block 26a, 26b is provided with a ram 27a, 27b or pair of side-by-side rams and independent means are provided for controlling each ram or pair of rams 27a, 27b.

Thus it will be realised that, in operation, it is possible to move the blocks 26a, 26b relative to each other so that the rate of pivot of the platform relative to the chassis and the rate of downward and backward movement of the wheels relative to the chassis can be independently controlled, this giving rise to several distinct advantages, for example in awkward un-loading situations and where it is desired to shift the weight of the trailer from the rear wheels 16 to the tow-bar 11, for example when the trailer is on soft ground compared with the towing tractor.

Various other modification can be made without departing from the scope of the invention. For example, as shown in Fig. 5 the load platform can be provided with sides and a swinging tail gate.

Furthermore, the hydraulic rams 27 (27a, 27b) can be replaced by other actuating means, for example, a screw threaded jack arrangement. Further the means for tipping the platform need not act on the linkage but can be connected directly between the chassis and the platform 12 in a conventional manner. It will be realised that in this modification, the platform will tip in the normal manner, however, owing to the constraint on the blocks 26 by the channels in the chassis 10, relative movement between the platform 12 and chassis 10 will, by virtue of the linkage cause the wheels to move relative to the chassis in the manner described above.

In the modification shown in Fig. 6 one ram 27c is provided between the chassis 10 and platform 12 and a further independently controlled ram 27d is provided between the chassis 10 and the member 18 carrying the wheels 16, this member being attached, as before, to the chassis 10 by the frame 20c and steady strut 30.

In further modifications shown diagrammatically in Figs 7 and 8 the pairs of rams 37a, 37b are connected between the chassis 10 and the ground engaging means 16 and the chassis 10 and the load platform 12, the connection point 36 on the chassis being either on the side of the blocks 26 towards the rear end of the trailer Fig. 7, or on the side of the blocks 26 towards the front end of the trailer, Fig. 8.

In a still further modification shown diagrammatically in Fig. 9 the frames 20a and 20b may be articulated and comprise two pivotally interconnected members 38a, 38b 38c, and 38d respectively, the hydraulic rams 27a, 27b being connected between the pivot points between the members and the chassis 10. In this modification sliding blocks 26 are unnecessary as the pivot point 40 of the members 38b, 38d is fixed.

Whereas the embodiment described relates to a trailer with wheels or the like near its rear and a tow hitch at its front, the trailer could be provided with steerable wheels at or near its front.

The arrangement of pivot axes may be modified for simplicity in construction, for example, referring to Fig. 1 the axes about which the load platform and the frame 20c pivot could be co-incident, and the axes on the member 18 about which the frames 20b and 20c pivot could be co-incident. In this latter case the strut 30 could be omitted.

WHAT I CLAIM IS: 1. A vehicle including a chassis, ground engaging means carried by a frame pivotally mounted to and below the chassis about a transverse axis thereof at or near one end of the chassis, a load platform pivotally mounted about a transverse axis at one end of its base to the chassis at or near said one end and operating means connected between said chassis and said frame and said chassis and said platform operable to pivot said frame and said platform about said axes, said frame being arranged such that movement of the ground engaging means thereon away from said chassis causes movement of the said means in the direction of a said one end of the chassis.

2. A vehicle as claimed in claim 1, in which said operating means includes a linkage connected between said platform and said ground engaging means in such a manner that with the ends of certain links of said linkage optionally constrained to move in a fixed path relative to said chassis, when said platform pivots said frame pivots relative to the chassis.

3. A vehicle as claimed in claim 2, in which one link of said linkage is pivotally connected to said load platform at one point and another link of the linkage is pivotally connected to said ground engaging means at a further point, and the ends of said links remote from said points are capable of being constrained to move in a fixed path relative to said chassis.

4. A vehicle as claimed in claim 2 or claim 3, in which said linkage, said frame carrying the ground engaging means and said platform form a parallelogram linkage arrangement.

5. A vehicle as claimed in claim 2, claim 3, or claim 4, in which said means for constraining said link ends to move in a fixed path relative to said chassis comprises roller means on said links engaged in a channel formed in or carried by said chassis.

6. A vehicle as claimed in claim 3, claim 4, or claim 5, in which said operating means includes also actuating means are connected between said chassis and said link ends.

7. A vehicle as claimed in claim 3, claim 4 or claim 5, in which said operating means are actuating means are connected between said chassis and said platform and/or said ground engaging means.

8. A vehicle as claimed in any one of the preceding claims, in which a steadying strut is pivotally mounted between said ground engaging means and said chassis to retain said ground engaging means in a fixed orientation irrespective of the orientation of the chassis.

9. A vehicle as claimed in claim 6 or

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. is desired to shift the weight of the trailer from the rear wheels 16 to the tow-bar 11, for example when the trailer is on soft ground compared with the towing tractor. Various other modification can be made without departing from the scope of the invention. For example, as shown in Fig. 5 the load platform can be provided with sides and a swinging tail gate. Furthermore, the hydraulic rams 27 (27a, 27b) can be replaced by other actuating means, for example, a screw threaded jack arrangement. Further the means for tipping the platform need not act on the linkage but can be connected directly between the chassis and the platform 12 in a conventional manner. It will be realised that in this modification, the platform will tip in the normal manner, however, owing to the constraint on the blocks 26 by the channels in the chassis 10, relative movement between the platform 12 and chassis 10 will, by virtue of the linkage cause the wheels to move relative to the chassis in the manner described above. In the modification shown in Fig. 6 one ram 27c is provided between the chassis 10 and platform 12 and a further independently controlled ram 27d is provided between the chassis 10 and the member 18 carrying the wheels 16, this member being attached, as before, to the chassis 10 by the frame 20c and steady strut 30. In further modifications shown diagrammatically in Figs 7 and 8 the pairs of rams 37a, 37b are connected between the chassis 10 and the ground engaging means 16 and the chassis 10 and the load platform 12, the connection point 36 on the chassis being either on the side of the blocks 26 towards the rear end of the trailer Fig. 7, or on the side of the blocks 26 towards the front end of the trailer, Fig. 8. In a still further modification shown diagrammatically in Fig. 9 the frames 20a and 20b may be articulated and comprise two pivotally interconnected members 38a, 38b 38c, and 38d respectively, the hydraulic rams 27a, 27b being connected between the pivot points between the members and the chassis 10. In this modification sliding blocks 26 are unnecessary as the pivot point 40 of the members 38b, 38d is fixed. Whereas the embodiment described relates to a trailer with wheels or the like near its rear and a tow hitch at its front, the trailer could be provided with steerable wheels at or near its front. The arrangement of pivot axes may be modified for simplicity in construction, for example, referring to Fig. 1 the axes about which the load platform and the frame 20c pivot could be co-incident, and the axes on the member 18 about which the frames 20b and 20c pivot could be co-incident. In this latter case the strut 30 could be omitted. WHAT I CLAIM IS:

1. A vehicle including a chassis, ground engaging means carried by a frame pivotally mounted to and below the chassis about a transverse axis thereof at or near one end of the chassis, a load platform pivotally mounted about a transverse axis at one end of its base to the chassis at or near said one end and operating means connected between said chassis and said frame and said chassis and said platform operable to pivot said frame and said platform about said axes, said frame being arranged such that movement of the ground engaging means thereon away from said chassis causes movement of the said means in the direction of a said one end of the chassis.

9. A vehicle as claimed in claim 6 or

claim 7 or claim 8, in which said actuating means each comprises hydraulic ram.

10. A vehicle as claimed in any one of claims 2 to 9, in which means are provided for removing the optional constraint on the link ends.

11. A vehicle as claimed in claim 1 or claim 2, in which said ends of certain links of the linkage are each pivotally mounted to a separate block the blocks being each independently constrainable relative to the chassis and each connected with actuating means.

12. A vehicle as claimed in any one of claims 2 to 11, in which each link and the frame carrying the ground engaging means comprises a rigid framework extending tranversely of the longitudinal axis of the chassis.

13. A vehicle as claimed in any one of the preceding claims, in which said ground engaging means comprise an axle carrying a wheel at each end.

14. A vehicle as claimed in any one of claims 1 to 12 in which said ground engaging means comprises a bogey including tandem axles each carrying at least one pair of wheels, or a bogey fitted with ground engaging skids or crawler tracks.

15. A vehicle as claimed in claim 3, claim 4 or claim 5 in which said operating means comprises an hydraulic ram between said chassis and said load platform and a further hydraulic ram between said chassis and said ground engaging means.

16. A vehicle as claimed in claim 15, in which the connection between said rams and the chassis is intermediate the said one end of the chassis and the pivotal connection of the links to the chassis.

17. A vehicle as claimed in claim 2, in which said links are articulated and said actuating means are connected between the articulation point and said chassis.

18. A vehicle substantially as hereinbefore decribed with reference to Figs. 1 to 3, or Fig. 4, or Figs 5 and 6 of the accompanying drawings.