GB2139770A

GB2139770A - Weighbridge stop

Info

Publication number: GB2139770A
Application number: GB08412027A
Authority: GB
Inventors: Christopher Edwin Watt
Original assignee: Shering & Co Ltd E
Current assignee: Shering & Co Ltd E
Priority date: 1983-05-13
Filing date: 1984-05-11
Publication date: 1984-11-14
Also published as: GB2139770B; GB8412027D0

Abstract

A weighbridge has a load platform provided with horizontal-displacement resistance means comprising at least one vertically extending leg 9 having a lower end portion 14 anchorable in use to a base 16 on which the weighbridge is mounted, and a lateral support portion 11 slidably disposed within a low-friction bush 10 in the load platform. <IMAGE>

Description

SPECIFICATION Weighbridge stop This invention relates to a weighbridge suitable for use in checking the weight of a vehicle.

In order to achieve the necessary high standard of accuracy required in a weighbridge it is important to ensure that the weighbridge be able to move completely freely in a vertical direction without the interference of any laterally acting e.g. frictional interference forces. On the other hand it will be appreciated that when a heavy vehicle is driven onto a weigh bridge even quite slowly, the latter will be subjected to substantial longitudinal displacement forces.

In orderto overcome this problem there have previously been used more or less complicated linkages and/or buffers to restrain the weighbridge against such longitudinal displacement. Such known arrangements are however of limited efficacy and/or require special installation procedures. They may also limit the overall reliability of the system.

It is an object of the present invention to avoid one or more of the above disadvantages.

The present invention provides a weighbridge having a load platform structure provided with a horizontal displacement resistance means, wherein said resistance means comprises at least one downwardly extending leg having a lower end portion anchorable in use to a base on which said weighbridge is mounted, and a lateral support portion slidably disposed within a low-friction bush means in said load platform structure.

Desirably at least two such legs are provided in horizontally spaced apart disposition to prevent rotation of the platform in the horizontal plane where the leg(s) is(are) of a rounded section, the bush means for one of said legs being formed and arranged for substantially preventing relative longitudinal or transverse horizontal movement between the platform and said one leg, the bush means for the other legs being formed and arranged for permitting relative movement, due to thermal expansion and contraction, between the parts of the platform at said other legs and the platform in the vicinity of said one leg, in use of the weighbridge.

The horizontal displacement resistance means of the present invention are of simple and economic construction and easy to install. Moreover their relative simplicity of construction contributes to the overall reliability of the weigh bridge.

Further preferred features and advantages of the present invention will appear from the following detailed description given by way of example of a preferred embodiment illustrated with reference to the accompanying drawings in which: Figure 1 is a schematic plan view of a weighbridge ofthe invention; and Figure 2 is detail sectionai side elevation showing one horizontal displacement resistance leg of the weighbridge of Figure 1.

Figure 1 shows a weighbridge 1 comprising a platform 2 supported on a framework of longitudinal and transverse girders 3,4 supported in turn on 6 laterally and longitudinally spaced apart load cells 5 along opposite sides 6, of the platform 2.

Along its central longitudinal axis X-X the weighbridge is provided in respective support members 7 with three spaced apart apertures 8 through which extend respective legs 9. As may be seen more clearly in Figure 2, the support members 7 are secured to the transverse girders 4 and a low-friction bush 10 is provided in each aperture 8 in which the leg 9 is a sliding fit. The bush 10 may be of any suitable material including for example metal or plastic, but preferably an inert low expansion low friction material such as polyteltrafluoroethylene (P.T.F.E.) or Tufnol (Trade Mark) available from Tufnol Ltd. of Birmingham, England is used.

At its upper end 11 the leg 9 has a head 12 which is held above the upper end 13 of the bush 10. The lower end 14 of the leg 9 extends downwardly into a recess 15 in the foundation 16 on which the weighbridge 1 is supported via the load cells 5, in which recess the leg is firmly secured in position with grouting material 17.

As may be seen from the drawing the form and arrangement of the particular leg shown (the central one in fact) permits full freedom of movement of the weighbridge in the vertical direction whilst at the same time preventing transverse displacement of the platform either longitudinally (under the influence of vehicle travel) or laterally (e.g. under the influence of cross-winds acting on the vehicle). It will however be apparent that with a circular section leg as used the weighbridge could still tend to rotate if only one leg were used. Accordingly two additional legs are used. In order though to allow for expansion movement of the platform at the other legs relative to the centre, the apertures 18 at the other legs are made elongate, their axes aligning with the central longitudinal axis of the bridge.

It will be apparent to those skilled in the art that various modifications may be made to the abovedescribed structure without departing from the scope of the present invention. Thus for example polygonal-section leg(s) could be used as also could different spatial position(s) and/or distributions thereof, not to mention of the load cells also. Also the legs could be bolted or otherwise secured to the foundation or suitable support elements anchored thereto. With regard to the legs it should be noted that it is important that the heads be disposed above the bushes and support members with sufficient clearance to ensure avoidance of contact therewith even if there is any bowing of the platform due to uneven vehicle weight distribution thereon.

It will also be appreciated that the present invention extends to other weighing apparatus of similar construction such as for example platform scales, where it is desired to limit horizontal displacement of the weighing platform.

1. Aweighbridge having a load platform structure provided with a horizontal displacement resistance means, wherein said resistance means comprises at least one downwardly extending leg having

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Weighbridge stop This invention relates to a weighbridge suitable for use in checking the weight of a vehicle. In order to achieve the necessary high standard of accuracy required in a weighbridge it is important to ensure that the weighbridge be able to move completely freely in a vertical direction without the interference of any laterally acting e.g. frictional interference forces. On the other hand it will be appreciated that when a heavy vehicle is driven onto a weigh bridge even quite slowly, the latter will be subjected to substantial longitudinal displacement forces. In orderto overcome this problem there have previously been used more or less complicated linkages and/or buffers to restrain the weighbridge against such longitudinal displacement. Such known arrangements are however of limited efficacy and/or require special installation procedures. They may also limit the overall reliability of the system. It is an object of the present invention to avoid one or more of the above disadvantages. The present invention provides a weighbridge having a load platform structure provided with a horizontal displacement resistance means, wherein said resistance means comprises at least one downwardly extending leg having a lower end portion anchorable in use to a base on which said weighbridge is mounted, and a lateral support portion slidably disposed within a low-friction bush means in said load platform structure. Desirably at least two such legs are provided in horizontally spaced apart disposition to prevent rotation of the platform in the horizontal plane where the leg(s) is(are) of a rounded section, the bush means for one of said legs being formed and arranged for substantially preventing relative longitudinal or transverse horizontal movement between the platform and said one leg, the bush means for the other legs being formed and arranged for permitting relative movement, due to thermal expansion and contraction, between the parts of the platform at said other legs and the platform in the vicinity of said one leg, in use of the weighbridge. The horizontal displacement resistance means of the present invention are of simple and economic construction and easy to install. Moreover their relative simplicity of construction contributes to the overall reliability of the weigh bridge. Further preferred features and advantages of the present invention will appear from the following detailed description given by way of example of a preferred embodiment illustrated with reference to the accompanying drawings in which: Figure 1 is a schematic plan view of a weighbridge ofthe invention; and Figure 2 is detail sectionai side elevation showing one horizontal displacement resistance leg of the weighbridge of Figure 1. Figure 1 shows a weighbridge 1 comprising a platform 2 supported on a framework of longitudinal and transverse girders 3,4 supported in turn on 6 laterally and longitudinally spaced apart load cells 5 along opposite sides 6, of the platform 2. Along its central longitudinal axis X-X the weighbridge is provided in respective support members 7 with three spaced apart apertures 8 through which extend respective legs 9. As may be seen more clearly in Figure 2, the support members 7 are secured to the transverse girders 4 and a low-friction bush 10 is provided in each aperture 8 in which the leg 9 is a sliding fit. The bush 10 may be of any suitable material including for example metal or plastic, but preferably an inert low expansion low friction material such as polyteltrafluoroethylene (P.T.F.E.) or Tufnol (Trade Mark) available from Tufnol Ltd. of Birmingham, England is used. At its upper end 11 the leg 9 has a head 12 which is held above the upper end 13 of the bush 10. The lower end 14 of the leg 9 extends downwardly into a recess 15 in the foundation 16 on which the weighbridge 1 is supported via the load cells 5, in which recess the leg is firmly secured in position with grouting material 17. As may be seen from the drawing the form and arrangement of the particular leg shown (the central one in fact) permits full freedom of movement of the weighbridge in the vertical direction whilst at the same time preventing transverse displacement of the platform either longitudinally (under the influence of vehicle travel) or laterally (e.g. under the influence of cross-winds acting on the vehicle). It will however be apparent that with a circular section leg as used the weighbridge could still tend to rotate if only one leg were used. Accordingly two additional legs are used. In order though to allow for expansion movement of the platform at the other legs relative to the centre, the apertures 18 at the other legs are made elongate, their axes aligning with the central longitudinal axis of the bridge. It will be apparent to those skilled in the art that various modifications may be made to the abovedescribed structure without departing from the scope of the present invention. Thus for example polygonal-section leg(s) could be used as also could different spatial position(s) and/or distributions thereof, not to mention of the load cells also. Also the legs could be bolted or otherwise secured to the foundation or suitable support elements anchored thereto. With regard to the legs it should be noted that it is important that the heads be disposed above the bushes and support members with sufficient clearance to ensure avoidance of contact therewith even if there is any bowing of the platform due to uneven vehicle weight distribution thereon. It will also be appreciated that the present invention extends to other weighing apparatus of similar construction such as for example platform scales, where it is desired to limit horizontal displacement of the weighing platform. CLAIMS

1. Aweighbridge having a load platform structure provided with a horizontal displacement resistance means, wherein said resistance means comprises at least one downwardly extending leg having a lower end portion anchorable in use to a base on which said weighbridge is mounted, and a lateral support portion slidably disposed within a lowfriction bush means in said load platform structure.

2. Aweighbridge according to claim 1 wherein at least two said legs are provided in horizontally spaced apart disposition so as to prevent rotation of the platform in the horizontal plane where the leg(s) is (are) of a rounded section, the bush means for one of said legs being formed and arranged for substantially preventing relative longitudinal or transverse horizontal movement between the platform and said one leg, the bush means for the other leg(s) being formed and arranged for permitting relative movement, due to thermal expansion and contraction, between the parts of the platform at said other leg(s) and the platform in the vicinity of said one leg, in use of the weighbridge.

3. Aweighbridge according to claim 2 wherein are provided at least three said legs spaced apart alongthe central longitudinal axis ofthe load platform.

4. A weighbridge according to any one of claims 1 to 3 wherein said bush means are of metal or plastics.

5. Aweighbridge according to claim 4wherein said bush means is of polytetrafluorethylene.

6. A weighbridge according to any one of claims 1 to 5 wherein said leg is of circular cross-sectional shape.

7. A weigh bridge according to any one of claims 1 to 5 wherein at least one said leg is of polygonal cross-sectional shape.

8. Aweighbrigde according to any one of claims 1 to 7 wherein said leg(s) has (have) a head portion formed and arranged to be vertically spaced apart from the bush means so as to avoid interference with the latter in the event of any bowing of the load platform during normal use of the weighbridge.

9. Aweighbridge substantially as described hereinbefore with particular reference to Figures 1 and 2 ofthe accompanying drawings.