GB2111940A - Bin clamping mechanism - Google Patents

Abstract

A refuse collection vehicle has a foot (11) on which a bin can be supported and a clamp (12) for clamping the bin to the foot, preparatory to lifting and tipping the bin. For folding the foot when it is not required for lifting a bin, there is associated with the clamp a rack and there is associated with the foot a toothed sector (26). By means of a piston and cylinder unit (15) the clamp and foot can be moved towards each other until the sector and foot are pivoted by the rack until the foot is vertical. <IMAGE>

Description

SPECIFICATION Bin clamping mechanism This invention relates to a bin clamping mechanism for a refuse collection vehicle of a generally known type having a foot for insertion under a bin and a clamp spaced from and movable relative to the foot to clamp the top edge of the bin, the foot and clamp being mounted on a support member which, when the bin has been clamped, can be lifted and tipped to empty the contents of the bin into the vehicle.

Such vehicles are usually used for the collection of refuse from commercial cylindrical bins mounted on castors or support legs.

Because the foot of the bin clamping mechanism projects substantially away from the vehicle, it is necessary for safety reasons that the foot should be folded away after use.

It has been proposed to mount the foot on a pivot and to provide manual locking means to lock the foot in an inoperative upright condition.

It is an object of the present invention to provide a bin clamping mechanism in which the foot is automatically folded after use to an upright inoperative condition.

According to one aspect of the invention, there is provided a bin clamping mechanism for a refuse collection vehicle, the clamping mechanism comprising a support; a foot slidably mounted relative to the support; a clamp slidably mounted relative to the support; a piston and cylinder unit adapted to cause relative sliding movement of the foot and the clamp; the foot being pivotable between an operative generally horizontal condition and a generally upright parked condition and a parking mechanism for pivoting the foot from its operative condition to its parked condition whenever the separation between the foot and the clamp is reduced to a minimum value by the piston and cylinder unit, wherein the parking mechanism includes a first element which is movable relative to the support and relative to the foot and which, during pivoting of the foot from its operative condition to its inoperative condition, co-operates with a second element fixed with respect to the foot to cause said pivoting of the foot.

Pivoting of the foot may take place whilst the axis about which the foot pivots remains at the same height above the ground.

Preferably, said second element is provided with a curved row of teeth and is adjacent to the pivot of the foot. For co-operation with the toothed element, the first element may be a generally upright rack adapted to engage the teeth and to rotate the second element and foot together between the operative and parked conditions when the foot and the clamp are moved relative to each other at a separation less than a predetermined threshold separation.

Thus, when emptying of bins has been completed and it is required to fold the foot away, the bin lifting and clamping mechanism is actuated so as to move the foot and the clamp towards each other. In the absence of a bin to be clamped, the separation of the foot and the clamp reduces to such an extent that the rack engages the toothed element and rotates the foot to the upright parked condition.

According to a further aspect of the invention, there is provided a bin clamping mechanism for a refuse collection vehicle, the clamp ing mechanism comprising a support; a foot slidably mounted relative to the support; a clamp slidably mounted relative to the support; a piston and cylinder unit adapted to cause relative sliding movement of the foot and the clamp; the foot being pivotable between an operative generally horizontal condition and a generally upright parked condition; an element having a curved row of teeth provided on the foot adjacent to the pivot thereof; and a generally upright toothed rack, the rack being adapted to engage the teeth of said element and to rotate the foot between the operative and parked conditions when the foot and clamp are moved relative to each other at a separation less than a predetermined threshold separation.

In one embodiment of the invention, the rack is fixed to the support. In an alternative embodiment, the rack is associated with abutment means engageable by the clamp or by a member associated with the clamp, to move the rack to engage the arcuate toothed element and rotate the foot.

There may be a tension spring rigidly secured by its upper end to the support and associated at its lower end with the rack.

Alternatively, there may be a compression spring having a rigid central member secured to its upper end and having its lower end secured to the support, the lower end of the central member being associated with the rack whereby movement of the clamp towards the foot causes the central member and hence the rack to be pushed downwardly to rotate the foot.

The invention will now be described in more detail by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side elevational view of a bin clamping mechanism provided at the rear of a refuse collection vehicle; Figure 2 is an enlarged elevational view of part of the mechanism shown in Fig. 1.

Referring firstly to Fig. 1, a clamping mechanism generally indicated at 10 comprises a foot 11 adapted to be inserted under a bin to be lifted, and a clamp 1 2 in the form of a hook which is adapted to clamp over the top rim of a bin. The clamp 1 2 is associated with a guide chute 13, the function of which is to guide the refuse into a hopper of the vehicle when the bin is tipped.

The foot, the clamp and the chute are associated with a support member 1 4 which, during clamping of the bin, adopts the vertical condition shown. Once the bin has been clamped, the support member is tipped so as to tip the contents of the bin into a hopper of the vehicle (not shown).

Both the foot 11 and the clamp 1 2 are movable relative to the support member 14.

Movement of the foot 11 and clamp 1 2 is controlled by a piston and cylinder unit 1 5 which may be either pneumatic or hydraulic, and which is constructed so as not to be fixed to the support member 1 4 but to be connected at its top end at 1 6 with the hook and chute 1 2 and 13, and at its lower end 1 7 with the foot. Fluid fed to the piston and cylinder unit drives a pair of pistons disposed in the opposite end regions of the cylinder, so that movement of the clamp 1 2 and chute 1 3 will take place simultaneously with movement of the foot 11, unless some resistance is met by one or other of the parts.Where, for example, the foot 11 has reached the chain dotted line position and is prevented from rising further by the presence of a heavy bin to be lifted, the piston and cylinder assembly 1 5 will act preferentially on the clamp 12, bringing it downwardly to engage the bin.

Once the bin has been clamped, the lifting and tipping mechanism can be operated.

When no further bins are to be emptied, the foot 11 is raised so as to adopt the chain dotted position indicated at 1 8 in Fig. 1, which is the parked condition in which the foot is disposed generally upright adjacent the support member 1 4.

The operation of the parking mechanism will be described in more detail with reference to Fig. 2.

A helical coiled spring 1 9 is secured at its upper end to a fixed abutment 20 on the support member 14. The lower end of the spring 19 is secured to a bolt 21 which passes through an open side of a generally channel section member 22, and is secured within the channel section to a rod 23. The lower end of the rod 23 is formed as a toothed rack 24, the teeth of which project through the slotted front of the channel section member 22.

The foot 11 is pivoted at 25 to a member slidably mounted on the support member 1 4.

An arcuate toothed element 26 is rigidly secured to the foot at the pivot 25 so as to be engageable by the toothed rack 24 to rotate the foot from the position 11 to the upright parked position 1 8.

In normal operation of the clamping mechanism 1 0, the arcuate toothed element 26 does not reach the position of the toothed rack 24. Thus, the foot remains in the horizontal operative condition.

When the piston and cylinder assembly 1 5 moves the foot 11 and clamp 1 2 towards each other, beyond a predetermined separation, the clamp 1 2 with its associated chute 1 3 moves downwardly to contact a projecting abutment 27 which is associated with the rod 23 disposed within the channel section 22.

When the clamp and chute meet the projecting abutment 27, further movement is resisted by the strong coil spring 19, since its lower end is secured at the bolt 21 to the rod 23. The piston and cylinder assembly therefore preferentially acts to raise the foot 11 relative to the support member 1 4.

A heel portion 28 of the foot moves upwardly until it meets the lower edge 29 of the support member 1 4. At this point, further movement is prevented. Continued operation of the piston and cylinder assembly 1 5 can then only act to move the clamp 1 2 and chute 1 3 downwardly against the force of the coiled tension spring 1 9. The clamp in turn forces downwardly the rod 23 from the position shown in Fig. 2, so that the teeth of the rack 24 meet with the teeth of the arcuate element 26 and rotate the foot to its upright parked condition 1 8.

When the vehicle has moved to a position where further bins are to be lifted and emptied, the piston and cylinder assembly is operated to reverse the sequence of events described above.

In the embodiment described, a coiled tension spring is used to control the lifting of the foot until a pivot axis of the foot reaches a predetermined height, at which it remains during pivoting. However, a coiled compression spring could also be used. In this case, which is not illustrated, the coiled compression spring could be mounted about a rigid central member secured to the upper end of the spring. The lower end of the spring would be secured to the support member in such a manner that the central member passed through the lower end of the spring and could be pushed downwardly by descent of the clamp 1 2 and chute 1 3. At the extreme lower end of the rigid central member, the rack would be provided.

In operation, the clamp and the foot would move towards each other until the descending clamp met the resistance of the compression spring. The foot would then continue to rise until it came into abutment with the lower edge 29 of the support member 14. The piston and cylinder assembly would then continue to operate to force the clamp 1 2 and chute 1 3 downwardly against the rigid central member and hence would compress the spring and force the rack downwardly to rotate the foot by engagement with the arcuate toothed element.

It will be appreciated that in either of the embodiments described, the movement of the foot between the parked and operative conditions and vice versa is positive, being controlled by the engagement of the teeth of the members 24 and 26, and is also damped by the interposition of the coiled tension spring 1 9 or compression spring referred to. It will also be seen that no special steps need to be taken to park or to lower the foot other than merely to operate the normal raising or lowering mechanism. When no bin is present, the parking and lowering pivotal movement of the foot can take place.

Claims (7)

1. A bin clamping mechanism for a refuse collection vehicle, the clamping mechanism comprising a support, a foot slidably mounted relative to the support, a clamp slidably mounted relative to the support, a piston and cylinder unit adapted to cause relative sliding movement of the foot and the clamp, the foot being pivotable between an operative generally horizontal condition and a generally upright parked condition, and a parking mechanism for pivoting the foot from its operative condition to its inoperative condition whenever the separation between the foot and the clamp is reduced to a minimum value by the piston and cylinder unit, wherein the parking mechanism includes a first element which is movable relative to the support and relative to the foot and which during pivoting of the foot from its operative condition to its inoperative condition, co-operates with a second element fixed with respect to the foot to cause said pivoting of the foot.

2. A clamping mechanism according to Claim 1 wherein the parking mechanism operates to pivot the foot about an axis which, during pivoting of the foot, remains stationary relative to a part of the bin clamping mechanism which is fixed with respect to a chassis of the vehicle in use.

3. A clamping mechanism according to Claim 1 or Claim 2 wherein said second element is an arcuate toothed member and said first element is a generally upright toothed rack, the rack being adapted to engage the arcuate toothed member and to rotate the foot between the operative and parked conditions when the foot and the clamp are moved relative to each other at a separation less than a predetermined threshold separation.

4. A clamping mechanism according to Claim 3 wherein the rack is fixed to the support member.

5. A clamping mechanism according to Claim 3 wherein the rack is associated with abutment means engageable by the clamp or by a member associated with the clamp, to move the rack to engage the arcuate toothed member and rotate the foot.

6. A bin clamping mechanism substantially as herein described with reference to and as shown in the accompanying drawings.

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