GB2102379A - Improvements in refuse collection vehicle bodies - Google Patents

Abstract

A refuse collection vehicle body 16 has a tailgate 20 incorporating a charging mechanism hinged to its roof at 24 and is raisable by rams 112. Refuse deposited through the mouth of a hopper 46 is charged into the body by the downward movement of a pivotally-mounted barrier plate 48 operated by a ram 58 acting through a rack and pinion mechanism 56, 54 which simultaneously lifts a sliding gate 86. A shutter 100 closes the mouth 46 during the charging stroke. Alternatively the plate 48 and gate 86 are arranged to operate in reverse directions and the plate 40 to pivot upwardly with the barrier plate 48 until it closes the mouth 46. <IMAGE>

Description

SPECIFICATION Improvements in refuse collection vehicle bodies This invention relates to a charging mechanism for the introduction of refuse into the body of a vehicle intended primarily for the collection of light refuse such as leaves and the contents of litter bins installed in public places, for example parks.

The invention also relates to a refuse collection vehicle fitted with such a charging mechanism.

According to the present invention there is provided a charging mechanism for the introduction of refuse into the body of a refuse collection vehicle, the mechanism comprising a hopper communicating with the interior of said body and having a wall thereof swept by the distal edge of a barrier pivotal between a first and a second position; the volume swept by the barrier constituting a receptacle for reception of refuse, and drive means arranged to drive the barrier in a charging stroke from the first to the second position to advance refuse into said interior.

Preferably the barrier has the form of a plate mounted on an axis extending transversely of the vehicle body and is mounted such that in its first position it extends upwardly and defines the inner boundary of the hopper mouth. Although any suitable drive means may be used, for example an electrical or hydraulic motor, the drive means preferably comprise a double-acting hydraulic ram, the piston of which is arranged to reciprocate a rack engaging a pinion coupled to said plate.

Refuse which has been charged into the vehicle body may tend to work back into the bottom of the hopper because of motion of the vehicle, for example when starting off uphill, and to prevent this the charging mechanism preferably comprises gate means moveable between a retention position for retaining refuse in the vehicle body and a retracted position which allows refuse to be charged into the body. The gate means may comprise a series of depending, vertical stakes arranged for reciprocation between the retention and retracted positions. Conveniently the gate means are mechanically linked to the drive means so that the gate means are in the retention position when the barrier is in the first position and in the retracted position when the barrier is in the second position.

As a safety measure the charging mechanism should incorporate closure means which are moveable to a closed position in which they restrict access to the mouth of the hopper, especially during movement of the barrier. To guard against human error or laziness it is desirable that the barrier should not be operable unless the shutter is in the closed position. A convenient form of shutter is part-cylindrical so that it may lie against said concave inner surface of the hopper when in a retracted position.

In an alternative arrangement the barrier is arranged to extend vertically downwards from its horizontal axis to form the forward wall of the hopper, the rear wall and the swept, rear portion of the hopper wall to pivot upwardly within the plate during the charging stroke until it closes the mouth of the hopper, which enables a separate shutter to be dispensed with. After the movement of the wall portion its internal surface is swept by the continued movement of the barrier during the remainder of its charging stroke. The location of the gate means is also reversed so that the stakes extend upwardly.

Usually the charging mechanism according to the present invention is incorporated in the tailgate of the refuse collection vehicle body. If the body is of the tipping type, the tailgate may be pivotally mounted on the top of the vehicle body so that, when the forward end of the body is raised, the tailgate retains its vertical position leaving a gap between the lower edge of the body and the tailgate through which the contents of the body are discharged. In order to widen the gap the tailgate is preferably provided with forwardly extending arms so that it may be hinged at a position forward of the rear edge of the vehicle body.Moreover, to ensure that the tailgate is fully open for the discharge of refuse and is not fouled by discharged refuse, especially on uneven ground, the charging mechanism preferably comprises actuating means for pivotting the tailgate away from the vehicle body.

While discharge solely under the influence of gravity is often quite adequate it is sometimes found that, where the refuse tends to stick to the inside of the body or the ground slopes forwardly, it is preferable to have an ejector mechanism for positively discharging refuse through the gap between the vehicle body and tailgate; such an ejector mechanism also prevents a pile of already discharged refuse from blocking the discharge of refuse still remaining in the body.

The mechanism according to the present invention thus provides a simple, effective and economical means of charging and compacting light refuse into the body of refuse collection vehicle, thus achieving the great benefits of spacesaving that are possible by compaction of this type of refuse.

Some embodiments of the invention will now be described by way of example, with reference to the accompanying drawings in which Figure 1 is a diagrammatic side elevation of a refuse collection vehicle having a body fitted with a charging mechanism according to the present invention, the body being shown in the normal, horizontal position for the collection of refuse; Figure 2 is an elevation, similar to that of Fig. 1 with the vehicle body in the tipped, discharge position; Figure 3 is a side elevation, on an enlarged scale and partly broken away, of the charging mechanism shown in the earlier figures in the Fig.

1 position; Figure 4 is a circuit diagram of the hydraulic system associated with the vehicle body; and, Figure 5 is a circuit diagram of the electrical system.

As shown in Figs. 1 and 2 a refuse collection vehicle 10 comprises a chassis 12 on the rear of which is pivotally mounted at 14 a body 16; the front end of the body 1 6 may be raised by means of a hydraulic ram 1 8. A tailgate 20 incorporating a charging mechanism is hinged to the roof of the body 1 6 at a position inset from the rear and side edges thereof. As shown in Fig. 4 the tailgate 20 is supported by two arms 22 which project forwardly over the roof of the body 1 6 to which they are each connected by a hinge pin 24 mounted on the roof.To the rear end of each arm 20 is attached a side plate 26 inset from the side of the body 1 6 and secured at its forward edge to a bulkhead 27; at the top the side plates 26 are bridged by a valance 28 and at the bottom by three plates; a bottom plate 30, intermediate plate 32 and cill plate 34, the upper edge of which is secured to a square section transverse member 36 surmounted by a rubber buffer strip 38. The three plates 30, 32, 34 are faced on their inner sides by a fixed part-cylindrical plate 40 also secured at its upper edge to a square-section member 42 similarly surmounted by a buffer strip 44. There is thus defined between the buffer strips 38, 44 and the lower edge of the valance 28 the mouth of a hopper 46 which opens at its lower and inner end onto the floor of the body 16.

Extending between the side plates 26 is a double-walled compression plate 48 pivotally mounted on two pins 50 each projecting from a lower corner thereof and capable of movement through a 1 800 arc between an upright position as shown in Fig. 3 in which it defines the rear of the upper portion of the hopper 46 and allows refuse to be deposited into the mouth thereof and a vertically downward position. A rubber strip 51 is received in a channel at the distal edge of the plate 48.

Each pin 50 is solid at its outer end with a double-walled, obovate pinion 52, between the semi-circular marginal edge portions of which extend a series of pins 54 and between the pointed ends of which extends a link pivot pin 55 for a purpose to be described later. The pinions 52 may be rotated through half a revolution by virtue of the engagement of their respective sets of pins 54 with the teeth of a corresponding nylon rack 56. Movement is imparted to each of the racks 56 by means of a double-acting hydraulic ram 58 positioned outside each side plate 26 in the following manner. A bracket 60 mounted on a framework 62 projecting rearwardly from each bulkhead 27 supports the upper ends of two channels 64 having their mouths facing each other, the lower ends of the channels 64 being supported by a similar bracket 66.The upper end of the barrel 68 of the ram 58 has two pins 70 projecting therefrom, each pin 70 being received in a hole bored through the top of each channel 64. The piston 72 of the ram 58 carries a transverse pin 74 which terminates at each end in a nylon block 76 which is slidably received in a respective channel 64. Also mounted on the pin 74 is a lower rack shoe bracket 78 supporting the lower end of a rack shoe 80, the upper end of which is mounted on an upper rack shoe bracket 82 having a pair of nylon blocks 84, each slidably received in a respective one of the channels 64.

Positioned forwardly of the compaction plate 48 when in its upright position is a sliding gate 86 consisting of a series of vertical forks 88 extending across the rear of the body 1 6 and tied at their upper ends by an upper tie bar Y0 and at an intermediate position by a lower tie bar 92. The forks 88 are retained for limited sliding movement in a vertical direction by a lower transverse bracket 94 and an upper bracket (not shown) extending between the side plates 26. At each lower corner thereof the gate 86 is pivotally connected to one end of a link arm 96, the other end of which receives the pin 55 on the pinion 52.

Each side plate 26 has a semi-circular channel 98 on the inside thereof between which is slidably received an arcuate section shutter 100. The upper edge of the shutter 100 is protected by a rubber strip 102 and around each side edge thereof is positioned a chain 104 engaged by a sprocket 106 driven by a hydraulic motor 108 through a gear chain 110.

The tailgate 20 may be pivoted upwardly by means of two single-acting hydraulic rams 112, the barrels of which are pivotally connected to a respective side of the body 1 6 at 114 and the pistons of which are connected to a respective one of the arms 22 at 116.

For normal operation the tailgate 20 is secured against the body 1 6 by means of two hooks 11 8, secured one at each end of a cross shaft 120 passing through the lower rear corner of the body 1 6. Each hook 11 8 is engagable with a pin 122 supported in a housing 1 24 projecting from the bottom of the bulkhead 27. Pivotal movement is imparted to the hooks 118 through a link arm 126 connected to a traveller 128 on a lead screw 130 which enables the hooks 11 8 to be locked in either an engaged or disengaged position.

The hydraulic circuit is shown in Fig. 4 and is supplied by a 1 2V DC power pack 1 32 or a pump driven by the vehicle power unit or any other means. The pack 132 is alternatively connectible through a direction ball valve 134 either to the body tipping ram 1 8 and the tailgate lifting rams 11 2 (each provided with a pressure-relief valve not shown) or to a circuit controlling the compaction plate 48 and the shutter 100. In this latter condition of the valve 134 the pack 132 is connected to a solenoid-operated detented direction valve 136 which is in turn connected to the hydraulic motor 108, two sequence valves 1 38, 140 and the double-acting compaction plate rams 58. A pressure switch 142 is incorporated between the switch 140 and the rams 58 and a tank 144 in the return to the valve 136.

The electrical circuit is shown in Fig. 5 and is supplied by a 1 2V battery 1 46 having its positive terminal earthed and its negative terminal connected to a circuit comprising a two-pole push switch 148; two solenoids 1 50, 1 52 controlling the directional hydraulic ball control valve 134; the hydraulically-operated pressure switch 142; a switch 1 54 operated by the shutter 100; an emergency stop switch 156; and an earthed motor start solenoid 158.

In operation, the body 1 6 of the vehicle 10 is used for collecting refuse when in its normal condition as shown in Figs. 1 and 3, with refuse being tipped into the mouth of the hopper 46.

When the hopper is full to the level of the top of the cill plate 34, the push switch 148 is operated which energies the motor start solenoid 1 58 to start the hydraulic pump 1 32 and the solenoid 150 to connect the pump 132 to the valve 136 and to the hydraulic motor 108. This causes the shutter 100, by virtue of the rotation of the sprockets 106 and their engagement with the respective chains 104, to move upwards to close off the mouth of the hopper 46.Closing of the shutter 100 is sensed by the pressure switch 142 and allows consequential downward and upward movement of the double-acting rams 58, these movements being controlled by the sequence valves 138, 140. Downward movement of the pistons 72 of the rams 58 carries the racks 56 downwardly and rotates the co-operating pinions 52 through 1 800. The compaction plate 48 is consequently rotated through a semi-circular arc until it extends vertically downwards, pushing refuse from the hopper into the body 1 6. When the body 1 6 is full of uncompacted refuse the downward movement of the compaction plate 48 serves to compact the contents as a further charge is driven in.The half-revolution performed by the pinions 52 which causes the downward movement of the plate 48 also serves to raise the gate 86 allowing passage of the refuse; the subsequent half-revolution in the opposite sense returning the forks to their lowered position in which they retain refuse in the body 1 6. After return movement of the compaction plate 48 to its Fig. 3 position, the shutter 100 is also returned to its Fig. 3 position.

After completion of the above-described sequence of operations the directional valve 134 is reverted manually to its other condition in which it supplies the body tipping ram 18 and the tailgate lifting rams 11 2. When the body 1 6 is full of compacted refuse or the desired amount of refuse has been collected the vehicle 10 is driven to the tipping site and the ram 1 8 extended to tip the body 1 6 about the pivot point 14; the rams 11 2 are next extended to open the tailgate 20 so that the vehicle body 1 6 assumes the Fig. 2 condition, allowing all the refuse to be discharged under the influence of gravity.Subsequent manual operation of the valves associated with the rams 18, 112 allows the vehicle 10 to revert to the Fig.

1 condition and be available for further refuse collection.

It will be appreciated that the above-described embodiment affords simple and efficient charging and compaction of refuse in the body 1 6 while safeguarding operatives against injury by operation of the compaction plate 48.

The above described embodiment is essentially a bottom-loading arrangement. While this is satisfactory for many types of refuse it has been found with certain types of refuse, particularly when wet, difficult to achieve sufficient forward movement and compaction with the compaction plate 48 acting against the bottom of the mass of refuse accumulated in the body 16. In such circumstances it is preferable to adopt an essentially top-loading charging mechanism.

In the top-loading mechanism the two pins 50 are replaced by a cross-shaft to which the distal edge of the compaction plate 48 is secured to form, in the normal, loading condition of the charging mechanism a barrier which extends vertically downwards to define the inner boundary of the hopper. The shutter 100 and its associated components such as the motor 108 are dispensed with and the part-cylindrical plate 40 rendered moveable by providing it at each side with sectorial side plates which are pivotally mounted on the cross-shaft, i.e. coaxially with, but independently of, the barrier. A hydraulic ram is provided at each side of the plate to move it from the normal loading position in which it forms the floor and rear wall of the hopper and an upper position in which its upper edge abuts the lower edge of the valance 28.

Not only are the rest position and operation of the barrier reversed but also those of the gate 86 so that the forks 88 project vertically upwards instead of downwards and in their retractable position are slightly below the level of the crossshaft.

In the normal loading condition of the charging mechanism the barrier extends vertically downwards, the moveable part-cylindrical plate is in its lower position and the forks extend upwardly. After loading, the rams 58 are operated together with those actuating the part-cylindrical plate to cause the barrier and plate to pivot upwardly together lifting the refuse contained therebetween until the plate abuts the valance; the movement of the barrier continues however until it extends vertically upwards (the position in fact shown in Fig.3). Simultaneously the forks 88 have retracted in the manner previously described in relation to the first embodiment to allow the rubbish that has been carried upwardly to fall or be pushed forwardly into the body 16, depending on the amount of refuse that is already accumulated in the body. It will be appreciated that the barrier has to operate when pushing accumulated refuse forwardly only against that at the top of the heap, thus reducing the resistance encountered by the barrier and enabling the interior of the body to be charged throughout its length with compacted refuse.

Claims (22)

1. A charging mechanism for the introduction of refuse into the body of a refuse collection vehicle, the mechanism comprising a hopper communicating with the interior of said body and having a wall thereof swept by the distal edge of a barrier pivotable between a first and a second position, the volume swept by the barrier constituting a receptacle for reception of refuse, and drive means arranged to drive the barrier in a charging stroke from the first to the second position to advance refuse into said interior.

2. A mechanism as claimed in Claim 1, in which the barrier is arranged to perform the charging stroke in a generally downward direction.

3. A mechanism as claimed in Claim 1, in which the barrier is arranged to perform the charging stroke in a generally upward direction.

4. A mechanism as claimed in Claims 1, 2 or 3, in which said wall is fixed.

5. A mechanism as claimed in Claims 1,2 or 3, in which said wall is arranged to move with the barrier for an initial portion of the charging stroke.

6. A mechanism as claimed in Claim 5, in which said wall is mounted for pivotal movement coaxially with the barrier.

7. A mechanism as claimed in any preceding Claim, in which the drive means comprise a double-acting hydraulic ram, the piston of which is arranged to reciprocate a rack engaging a pinion coupled to said barrier.

8. A mechanism as claimed in any preceding Claim, and additionally comprising gate means moveable between a retention position for retaining refuse in said interior and a retracted position which allows refuse to be advanced into said interior.

9. A mechanism as claimed in Claim 8, in which the gate means comprise a series of stakes arranged for reciprocation between said retention position and said retracted pOsition.

10. A mechanism as claimed in Claims 8 or 9, in which the gate means are mechanically linked to said drive means such that the gate means are in said retention position when the barrier is in the first position and in the retracted position when the barrier is in said second position.

11. A mechanism as claimed in any preceding Claim, and additionally comprising closure means which are moveable from a withdrawn to a closure position to restrict access to said receptacle during the charging stroke.

12. A mechanism as claimed in Claim 11, in which the closure means comprise a shutter having a configuration corresponding to that of said wall and arranged to lie, when in said withdrawn position against the outside of said wall.

1 3. A mechanism as claimed in Claims 11 or 12, and additionally comprising closure drive means for driving the closure means between its withdrawn and closure positions.

14. A mechanism as claimed in Claim 13, in which the closure drive means comprise a pinion and co-operating engagement means mounted on an arcuate edge of the shutter.

1 5. A mechanism as claimed in any one of Claims 11 to 14, in which the barrier is arranged to perform its charging stroke only when the closure means are in the closure position.

16. A charging mechanism for the introduction of refuse into the body of a refuse collection vehicle, substantially as herein described with reference to the accompanying drawings.

1 7. A tippable refuse collection vehicle body having a tailgate comprising a mechanism as claimed in any one of the preceding Claims hingedly mounted to the top thereof such that the tailgate may be pivoted away therefrom to leave a gap between the rear of the body floor and the tailgate through which the refuse may be discharged.

1 8. A body mechanism as claimed in Claim 17, in which the tailgate is hinged at a point inset from the rear end of the body.

19. A mechanism as claimed in Claim 17 or 18 and additionally comprising hydraulic means for pivoting the tailgate relatively to the body.

20. A mechanism as claimed in Claim 17, 18 or 1 9 and additionally comprising locking means for locking the tailgate in the closed position.

21. A refuse collection vehicle body substantially as herein described with reference to the accompanying drawings.

22. The features as herein disclosed, or their equivalents, in any novel selection.