GB2256494A

GB2256494A - Weighing apparatus for livestock

Info

Publication number: GB2256494A
Application number: GB9210818A
Authority: GB
Inventors: Kenneth Edwin Wood
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-06-05
Filing date: 1992-05-21
Publication date: 1992-12-09
Also published as: GB9210818D0

Abstract

A weighing apparatus comprises an outer frame (11) and an inner frame (30) mounted in the outer frame (11), there being load sensing means (70, 70a) to detect movement of the inner frame (30) relative to the outer frame (11) when an item to be weighed is received by the inner frame (11), the mounting for the inner frame on the outer frame comprising ramp means having a first elongate part (50) secured to the inner (30) or outer (11) frame which extends at an angle to the horizontal and vertical and a second runner part (55) secured to the outer (11) or inner (30) frame respectively which is adapted to ride in or on the first part (50). The load sensing means may be a load cell or a spring balance. The construction prevents instability when the apparatus is used to weigh livestock. Portability is ensured by a retractable wheel arrangement 70, 72, 73, 76. <IMAGE>

Description

Title: Weighing Apparatus.

Description of Invention This invention relates to a weighing apparatus and more particularly, but not exclusively, to a weighing apparatus for weighing livestock such as pigs, cattle, or sheep.

Weighing apparatus for this purpose are known, which comprise a suspended frame, with some load sensing means provided in the suspension to sense the weight of the animal being weighed.

Because the frame is suspended, the frame is relatively unstable and in particular, can swing which tends to disturb an animal being weighed.

In accordance with the invention I provide a weighing apparatus comprising an outer frame adapted to be supported on the ground and an inner frame mounted in the outer frame, there being load sensing means to detect movement of the inner frame relative to the outer frame when an item to be weighed is received by the inner frame, the mounting for the inner frame on the outer frame comprising ramp means having a first elongate part secured to the inner or outer frame which extends transverse to the horizontal and vertical and a second runner part secured to the outer or inner frame respectively which is adapted to ride in or on the ramp means.

The outer frame may comprise a framework providing a substantially box-like structure, and the inner frame may too comprise a framework providing a substantially box-like structure.

The inner frame may include a weigh platform on which the item to be weighed is placed. The inner frame may further comprise wall and gate members to confine the article in the inner frame during weighing.

The load sensing means may comprise means to sense movement of the inner frame in the outer frame caused by an item being received by the inner frame.

For example, the load sensing means may comprise a load cell located between framework elements of the inner and outer frames, or alternatively the load sensing means may comprise a proximity sensor to sense relative movement between framework elements of the inner and outer frames, or other suitable load sensing means.

A pair of ramp means may be provided at either side of the weighing apparatus.

Each of the first elongate parts of the ramp means may comprise a reentrant channel section part having an opening in which the respective second part may ride. In one example, the first elongate part of the guide means extends at about 45" to the horizontal and vertical and is rigidly secured to the outer frame. The second runner part of the or each ramp means may also be elongate and may be rigidly secured to the inner frame.

Where a pair of ramp means are provided, the channel section first parts and the second, runner, parts may extend upwardly outwardly of one end of the respective inner and outer frame, the extensions of the first elongate parts being interconnected by a first cross brace framework element and the extensions of the second runner parts being interconnected by a second cross brace framework element.

Friction reducing means may be provided between the first and second parts of the or each ramp means.

The friction reducing means may in one example comprise rollers located in the or each of the channel section first parts in or on which the second parts ride.

The weighing apparatus may comprise a mechanism to enable the apparatus easily to be moved from place to place manually.

The mechanism may comprise a pair of lifting members pivotally secured to and extending outwardly of one end of the outer frame of the weighing apparatus, the lifting members having wheels provided on the outwardly extending parts, and there being a linkage from each of the lifting members to a respective lifting lever which is pivoted to the outer frame such that the lifting levers may be raised to lift the lifting members to cause the wheels carried thereby to be brought into contact with the ground.

The invention will now be described with reference to the accompanying drawings in which: FIGURE 1 is a side perspective illustrative view of a weighing apparatus in accordance with the invention.

FIGURE 2 is a cross section along the lines 2-2 of Figure 1, and, FIGURE 3 is a fragmentary side section taken along the lines 3-3 of Figure 1.

FIGURE 4 is a fragmentary perspective view of part of a modified weighing apparatus.

Referring to figures 1 to 3 of the drawings, there is shown a weighing apparatus 10 for weighing livestock, the apparatus 10 comprising an outer frame 11 having upright bars 12 to 17 and horizontal bars 19 to 25 welded or otherwise secured together to provide a substantially box-like structure which is adapted to be supported on the ground.

Mounted within the outer frame 11 is an inner frame 30 which comprises upright bars 31-36 and horizontal bars 37-44 again welded or otherwise secured together to provide a substantially box-like structure slightly smaller in width, but slightly greater in length, than the outer frame 11.

The inner frame 30 comprises a weigh platform 46 on which in use livestock to be weighed may stand, and mesh side walls 47 and 48. Gates would be provided on the inner frame 30 as necessary at each end of the inner frame 30 to enable livestock standing on weigh platform 46 to be confined. A mesh roof may be provided on the inner frame 30 if necessary.

The inner frame 30 is mounted with respect to the outer frame by a pair of ramp means each comprising a re-entrant elongate channel shaped part 50 which extends at an angle of 45" to the horizontal and vertical and is secured to the outer frame 11 at three positions, each being the positions where the parts 50 cross respective uprights 12,13,14, or 15,16,17.

The parts 50 extend upwardly at 51,52, outwardly of the uprights 12,15, and the extensions 51,52, are interconnected by a first cross brace 54.

Received within each of the re-entrant channels of the channel shaped parts 50, are runner parts 55 which are secured, for example by welding, to the respective uprights 31,32,33, or 34,35,36, of the inner frame 30 and also extend at 45" to the horizontal and vertical. The runners 55 extend upwardly at 57,58, outwardly of the uprights 31,36, and the extensions 57,58, are interconnected by a second cross brace 56.

Referring particularly to figure 2, it can be seen that the runner parts 55 are supported in the channel shaped parts 50 by rollers 60, although preferably a maximum of only three sets of rollers (the rollers are provided in pairs) provided throughout the length of the runner parts 55.

Referring particularly to figure 3, within extensions 51,52, of the channel section parts 50, coil springs 61 are provided, which together are sufficiently strong to support the weight of the inner frame 30 in a position relative to the outer frame such that there is a datum distance d between cross braces 54 and 56.

Also, when the distance d between the cross braces 54 and 56 changes, as described hereinafter, the springs 61 together provide sufficient restoring force to move the cross brace 56 and hence inner frame 30 back to the datum position shown.

The coil springs 61 need to be sufficiently strong both to restore the cross brace 56 to its starting position once the item is removed from the inner frame 30, and to ensure that the distance d does not decrease more than a predetermined amount, for a maximum expected weight to be received by the inner frame 30.

It will be appreciated that any weight placed on the weigh platform 46 will cause the inner frame 30 to move downwardly relative to the outer frame 11 at an angle of 45" by virtue of being constrained by the runner parts 55 and channel shaped parts 50. This movement will cause the distance d between the cross braces 54 and 56 to decrease. However, by virtue of the construction of the ramp means, the weigh platform 46 will always remain substantially horizontal.

The decrease in distance d between the cross braces 54 and 56 is detected by a load sensing means 70 which comprises, for example, a load cell 71 which gives an input to an electronic reader 72. By suitable calibration of the sensing means 70, any movement of cross brace 56 towards the cross brace 54 can be translated into a measure of the weight placed on the weigh platform 46.

The construction of load sensing means such as indicated at 70 is well known and further detailed description is not considered necessary. In place of a load cell 71, a proximity sensor could be used or any other sensing means to detect a change in distance between the cross braces 54 and 56 caused by movement of the inner frame 30 relative to the outer frame 11.

It will be appreciated by those skilled in the art of weighing apparatus that the apparatus 10 described has certain intrinsic inaccuracies arising from its construction. Particularly, the entire weight of an item placed on the weigh platform 46 will not be transmitted through the load cell 71 or other sensing means, by virtue of the channel shaped parts 50 and runner parts 55 being transverse at 450 to the vertical.

Surprisingly however, it has been found that provided the rollers 60 are adequately friction reducing, the inaccuracy of the weighing apparatus can be reduced to as little as 2-3% Whereas such an apparatus may not therefore be acceptable for use in an application where greater accuracy is required, particularly for weighing livestock such inaccuracies are perfectly acceptable, particularly as in any case, livestock tends to move during weighing, thereby making a very accurate indication of the weight of the livestock in any event, nearly impossible.

It is envisaged that a weigh apparatus such as indicated at 10 in the drawings, would be of use to a stockman to determine with greater accuracy than mere estimation, the weight of an animal.

The apparatus incorporates means to enable the apparatus easily to be moved from one location to another.

Mounted with respect to the outer frame 11, at either side of the apparatus 10, is a lifting lever 70 which is pivotable about a pivot 71 relative to the outer frame 11. The lever 70 is of cranked configuration, and is pivotally connected to a linkage 72, which in turn is pivotally connected to a lifting bar 73.

The lifting bar 73 is pivotable relative to outer frame 11 about a pivot axis 74.

The lifting bar 73 has at its outermost end, a small wheel 76.

In the drawings, the lever 70 is shown in a folded condition such that the lifting bar 73 is generally parallel to the horizontal 24 of the outer frame 11 such that the wheel 76 is not in contact with the ground. Hence, the horizontals 20,21,24,25, of the outer frame 11 are firmly seated on the ground.

When the levers 70 are raised as indicated by the arrow "UP" the lifting bars 73 are pivoted about axis 74 to bring the wheels 76 into engagement with the ground.

Each linkage 72 is arranged to go over-centre with respect to its pivot P to the lifting lever 70 and hence the lifting lever 70 can be locked in its upper position.

With both lifting levers 70 locked in their upper positions, it will be appreciated that the weighing apparatus 10 conveniently may be wheeled from place to place by lifting the apparatus 10 using the levers 70 as handles.

Various modifications may be made without departing from the scope of the invention. For example, instead of the channel section parts 50 and runner parts 55 extending at an angle of 45" to the horizontal and vertical, the ramp means may extend at other angles. Obviously, the closer to the vertical position, the more accurate the weighing apparatus becomes, but the 45" angle chosen provides a good compromise between accuracy and convenience in that the height of the apparatus 10 overall can be kept to a convenient low height.

Also, the more vertical the ramp means are made, the less stable the inner frame 30 becomes relative to the outer frame 11.

The apparatus 10 could be made bigger or smaller than shown specifically to suit different kinds of livestock. The apparatus shown is particularly configured for weighing pigs.

The inner 30 and outer 11 frame arrangements could be altered to suit a particular application and thus need not be of the box-like configurations shown.

In another application, a weigh platform 46 as such may not be required, but an article to be weighed may otherwise be secured in or on the inner frame 30.

Referring to figure 4, part of a modified apparatus 10a is shown in which the load sensing means 70 as used in the figures 1 to 3 embodiment, is replaced by a mechanical weight sensing device 70a comprising a spring balance 71a. Secured to cross brace 54 of the outer frame 11 is a mounting member M which can be bolted or otherwise fastened, or welded or otherwise fixed to the cross brace 54 as desired. The mounting member M comprises a first part P1 which extends upwardly and outwardly of the outer frame 11 at approximately 450 to the vertical and horizontal beneath the cross brace 56 of the inner frame 30, and a second part P2 which is approximately perpendicular to the first part P1 and extends upwardly.

The balance 71a is located between the second part P2 of the mounting members M and the cross brace 56 of the inner frame 30, a first coupling C1 coupling the balance 71a to the second part P2 of the mounting member M, and a second coupling means C2 coupling the balance 71a to the cross brace 56.

Thus as an item is placed in the inner frame 30 and the distance d between cross braces 54 and 56 decreases, the coupling means C1,C2 will tend to be moved apart thus to cause the balance 71a to indicate the weight of the item.

It will be appreciated that when no item is placed in the inner frame 30, the balance 71a may not read zero and that by virtue of the ramp means and the springs 61 resisting movement of the inner frame 30, the spring balance 71a needs to be especially calibrated for use in the apparatus 10a. A mechanical weighing device other than a spring balance 71a could be provided instead as desired.

The features disclosed in the foregoing description or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, or a class or group of substances or compositions, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A weighing apparatus comprising an outer frame and an inner frame mounted in the outer frame, there being load sensing means to detect movement of the inner frame relative to the outer frame when an item to be weighed is received by the inner frame, the mounting for the inner frame on the outer frame comprising ramp means having a first elongate part secured to the inner or outer frame which extends transverse to the horizontal and vertical and a second runner part secured to the outer or inner frame respectively which is adapted to ride in or on the first part.

2. An apparatus according to claim 1 wherein the outer frame comprises a framework providing a substantially box-like structure.

3. An apparatus according to claim 1 or claim 2 wherein the inner frame comprises a framework providing a substantially box-like structure.

4. An apparatus according to any one of claims 1 to 3 wherein the inner frame includes a weigh platform on which the item to be weighed is placed.

5. An apparatus according to any one of claims 1 to 4 wherein the inner frame further comprises wall and gate members to confine the article in the inner frame during weighing.

6. An apparatus according to any one of claims 1 to 5 wherein the load sensing means comprises means to sense movement of the inner frame in the outer frame caused by an item being received by the inner frame.

7. An apparatus according to claim 6 wherein the load sensing means comprises a load cell located between framework elements of the inner and outer frames.

8. An apparatus according to claim 6 wherein the load sensing means comprises a proximity sensor to sense relative movement between framework elements of the inner and outer frames.

9. An apparatus according to claim 6 wherein the load sensing means comprises a mechanical weight sensing device.

10. An apparatus according to claim 9 wherein the weighing device comprises a spring balance having a first coupling for coupling the balance relative to the outer frame and a second coupling for coupling the balance relative to the inner frame, movement of the inner frame relative to the outer frame caused as a result of an item being received by the inner frame, tending to move the first and second couplings relatively apart thus to cause the balance to indicate the weight of the item.

11. An apparatus according to any one of the preceding claims wherein a pair of ramp means are provided, one at either side of the weighing apparatus.

12. An apparatus according to claim 11 wherein each of the first elongate parts of the ramp means comprises a re-entrant channel section part having an opening in which the respective second part rides.

13. An apparatus according to claim 12 wherein the channel section first parts and the second, runner parts extend upwardly outwardly of one end of the respective inner and outer frame, the extensions of the first elongate parts being interconnected by a first cross brace framework element and the extensions of the second runner parts being interconnected by a second cross brace framework element.

14. An apparatus according to any one of the preceding claims wherein the first elongate part or parts of the guide means extend at about 450 to the horizontal and vertical and is or are rigidly secured to the outer frame.

15. An apparatus according to claim 14 wherein the second runner part or parts of the or each ramp means is also elongate and rigidly secured to the inner frame.

16. An apparatus according to any one of claims 12 to 14 wherein friction reducing means are provided between the first and second parts of the or each ramp means.

17. An apparatus according to claim 16 wherein the friction reducing means comprises rollers located in the or each of the channel section first parts in or on which the second parts ride.

18. An apparatus according to any one of the preceding claims wherein the weighing apparatus comprises a mechanism to enable the apparatus easily to be moved from place to place manually.

19. An apparatus according to claim 18 wherein the mechanism comprises a pair of lifting members pivotally secured to and extending outwardly of one end of the outer frame of the weighing apparatus, the lifting members having wheels provided on the outwardly extending parts, and there being a linkage from each of the lifting members to a respective lifting lever which is pivoted to the outer frame such that the lifting levers may be raised to lift the lifting members to cause the wheels carried thereby to be brought into contact with the ground.

20. A weighing apparatus substantially as hereinbefore described with reference to and as shown in figures 1 to 3 or figure 4 of the accompanying drawings.

21. Any novel feature or novel combination of features as herein disclosed and/or shown in the accompanying drawings.