GB2229988A - Improvements in waste disposal vehicles - Google Patents

Abstract

A waste disposal vehicle having a rear end loader equipped with a compacting means for transferring waste from the rear end loader into a tippable bulk container mounted on the vehicle chassis, and also having retractable lifting arms for small wheeled containers, wherein said lifting arms (18) have, respectively at different heights and distances from the rear end loader when the arms are extended, first hooking means (20) for engagement with one type of container and second hooking means (22) for an alternative type of container. To open a spring-loaded lid of a container, a retractable forked arm may be provided which can be manually moved into an operative position in the charge box (Fig. 3-5, not shown). <IMAGE>

Description

Improvements in Waste Disposal Vehicles This invention relates generally to waste disposal vehicles, and in particular to a waste disposal vehicle of the kind having a rear end loader which includes a compacting means for transferring waste from the rear end loader into the bulk container mounted on the chassis of the vehicle.

Waste disposal vehicles of the kind described are known wherein a pair of lifting arms are provided whereby, by use of chain attachments, a waste disposal skip can be picked up and tipped into the rear end loader. Additionally, and for alternative use, a pair of retractable lifting brackets may be provided for lifting a small wheeled container, such as a "Eurocart", and tipping its contents into the rear end loader.

The Eurocart has lifting bosses, as well,as a spring loaded lid which has to be automatically opened by suitable means in order to tip out its contents. Other small wheeled containers of steel, such as the Wimpey Wheelaway (Trade Mark), have lifting handles and manually openable lids, and are not capable of being handled by a vehicle adapted to handle E 1rocarts. These other small wheeled containers are referred to herein as alternative bins. A rear end loader can be adapted to handle alternative bins instead of Eurocarts, but there are problems involved in adapting a rear end loader te handle both types of small container in addition to large containers or skips.

A major difficulty which arises in trying to increase the versatility of a rear end loading waste disposal vehicle is that of avoiding fouling of all the movable parts, i.e. the skip lifting and tipping means, the small container lifting and tipping means, the automatic lid opening means in the case of emptying Eurocarts and the compacting means.

Conventional rear end loading waste disposal vehicles equipped with the above-described facilities are normally driven electro-pneumatically, and safety circuits are incorporated to prevent simultaneous operations which would give rise to fouling of moving parts and consequential damage. Advantageously, however, all the facilities would be hydraulically powered, and be capable of operation through tappings into the basic hydraulics of the vehicle.

According to the invention, therefore, there is provided a waste disposal vehicle of the kind described, wherein the rear end loader is equipped with retractable lifting brackets for small wheeled containers, said lifting brackets having, respectively at differing heights and differing distances from the rear end loader when the arms are extended rearwardly for picking up such containers, first hooking means for engagement with a Eurocart and second hooking means for engagement with an alternative bin.

The first hooking means is adapted to engage the lifting lugs provided for this purpose on opposite sides of a Eurocart, and the second hooking means, at the lower level and lesser distance in the rearward direction when the brackets are extended for lifting, is adapted to clasp the handles conventionally provided at opposite sides of an alternative bin to enable manual emptying thereof.

When a Eurocart is lifted, the container is also tipped and lugs associated with the spring loaded lid on opposite sides of the container are brought into engagement with a pair of spaced fork means mounted in the rear end loader, whereby continued movement of the lifting brackets causes the lid of the Eurocart to open. When an alternative bin is lifted and tipped, the fork means is not required, because the lid is opened manually in advance.

As is conventional, the compacting means preferably consists of a paddle blade pivotally mounted on a slider compaction blade. The paddle blade and the slider compaction blade are independently operable. In order to prevent fouling during subsequent operations, the abovedescribed fork means are most preferably linked together for retractable movement about a horizontal pivot axis, said linked fork means having a projecting limb which is engaged by the slider compaction blade on descent thereof when the compactor means is used, thereby to cause the fork means to retract to a safe position. Thus, after any container has been emptied into the rear end loader, immediately subsequent use of the compaction means ensures that the fork means is out of the way before the next container is lifted and tipped.A handle is provided for manually restoring the forks to the operative position, for use when the next container to be emptied is a Eurocart. However, if for example a waste disposal skip (large container) is next to be emptied, it is essential for the fork means to be retracted in order tc avoid damage.

In accordance with a most preferred feature of the invention, all the rear loader facilities, i.e. large container lift and tip, small container lift and tip, and the compaction means, are hydraulically driven. The use of hydraulic drives is facilitated when, as is preferred, the bulk storage container on the vehicle chassis is emptied by tipping said bulk storage container, dispensing with the requirement for an internal waste ejector means. As is usual, the rear end loader has to be lifted away from the rear end of the bulk storage container prior to emptying and, in the case of tipping to effect emptying, hydraulic drives for tipping and for lifting away the rear end loader are interlinked so that the rear end loader has to be lifted away prior to tipping, so that risk of damage to the rear end loader, which otherwise would strike the ground, is avoided.

As hydraulic controls and drives are preferably employed for the rear end loader facilities, a number of safety devices are most desirably incorporated.

First, in addition to the handle for moving the fork means for a Eurocart lid, which is wholly mechanical in operation, three control handles are provided for the rear end loader hydraulically operated facilities. The first is a two position handle which operates in conjunction with a diverter valve to enable operation of either the small container lift and tip or the pivotal movement of the paddle blade of the compacting means. Thus, operation of the small bin lift (one position of the first handle) and operation of the paddle blade (other position sf the first handle) are not possible simultaneously. The second handle is provided for operation of the slider compaction blade and the third handle is provided for operation of the large container lift.

In conjunction with these separate handles, a first dump valve is provided at the top of the path of movement of the slider compaction blade and a second dump valve is provided adjacent the small container lift bracket means. The first dump valve must be closed, i.e. the slider compaction blade must be in its top rest position, to enable the small container lift and tip to be used. If this first dump valve is open, the small container lift and tip drive is disabled. The second dump valve must be closed, i.e.

small container lift bracket means fully down, to enable use of the slider compaction blade. If this valve is open, the slider compaction blade drive is disabled. Thus, simultaneous operation of the small container lift and of the slider compaction blade is not possible. Inadvertent operation of the large container (skip) lift simultaneously with the slider compaction blade is less important, as the mechanisms do not foul one another.

The above-described handle controls and dump valves ensure, within practical limits, that the operator is unable to effect simultaneous operations, at the rear end loader, which could give rise to fouling of parts and consequential damage.

A preferred arrangement of waste disposal vehicle in accordance with the invention will now be described by way of example with reference to the accompanying drawings, in which:- Figure 1 is a rear elevational view of one side of the lower part of a rear end loader; Figure 2 is a view of the same part from the side; Figure 3 is a rear view of one side of the upper part of a rear end loader; Figure 4 shows detail of a fork arm from Figure 3; Figure 5 is a diagrammatic view of part of the rear end loader from the side; and Figure 6 shows an hydraulic drive control means.

The general form of a waste disposal vehicle with rear end loader is well known and accoringly will not be described in detail. Such a vehicle has a bulk storage container mounted on the vehicle chassis, said bulk container having a rear end loader depending from its rear end. The rear end loader can be lifted and separated from the bulk container for emptying of the latter. In the present case this emptying procedure is effected by tipping the bulk storage container, so that a waste material ejection means within said bulk container is not required.

The rear end loader is equipped, in a conventional manner, with lifting and tipping means for skips, referred to herein as large containers, and compacting means for transferring waste from the rear end loader into the bulk storage container. Additionally, the rear end loader in accordance with the invention has means for lifting and tipping small containers into the rear end loader, and can handle two types of such container, referred to herein as Eurocarts and alternative bins. The rear end loader facilities, in the preferred vehicle in accordance with the invention, are hydraulically operated, via circuits tapped into the main hydraulic power supply of the vehicle.

Referring to Figures 1 and 2, a rear end loader has a charge box 10. The main cross member at the lower rear end of this charge box is referenced 12. Welded between the main cross member 12 on the underside of the charge box and a lower cross member 13 are a pair of ram supporting brackets 14 spaced apart across the width of the charge box.

Associated with each ram supporting bracket 14 is a pivot support bracket 16. Pivotally mounted on the respective brackets 16 are a pair of bracket arms 18 having first hook means 20 and second hook means 22. Figures 1 and 2 show the bracket arms 18 extending rearwardly away from the charge box, ready for use, but the arms can be folded back about the pivot axis 24 to extend laterally across the vehicle below the charge box, when said bracket arms are not required. In the rearwardly extending condition, the pair of bracket arms 18 can be pivotted upwardly, to lift and tip a small container, by means of a pair of hydraulic rams 26 pivotally mounted at one end to the ram supporting brackets 16.Torque tube 28 extends across the vehicle to interconnect the two bracket arms 18, thus ensuring synchronism of operation of the rams 26, which connect with the torque tube 28 by means of ram support plates 29.

The first hook means 20 is adapted to engage the lifting lugs conventionally provided on opposite sides of a Eurocart, and is equipped with a spring loaded hook closure 30.

Second hook means 22, nearer the rear end of the charge box and lower down, is adapted to engage the shallow U-shaped handles of an alternative bin, and is equipped with a spring loaded hook closure 32. When either one of such small containers is lifted, a resilient buffer 34 on the torque tube is brought into engagement with the container to cause tipping thereof.

In Figures 1 and 2, reference 36 indicates the large container (skip) lift guide and reference 38 the skip tipping yoke, which are substantially conventional.

When a Eurocart is lifted and tipped, its spring loaded lid must be opened automatically, and the means provided for this purpose is shown in Figures 3 and 4.

Reference 40 denotes the side wall of the charge box, where the track 42 for the slider compaction blade of the compacting means is provided in a conventional manner.

Carried by this wall, and likewise on the other side of the vehicle, is an arm assembly 44 carrying a forked arm 46 shown in enlargement and from the side in Figure 4.

The two arm assemblies 44 are interconnected by cross member 48, so that a single cranked handle 50, interconnected through a pivotal mounting 49 with the arm assembly 44 on one side (the illustrated side) of the vehicle, can be manually operated to move the forked arms 46 into an operative position or retract them to an inoperative safe position.

In the operative position of the forked arms 46, when a Eurocart is lifted, lugs provided for the purpose on opposite sides of the container are brought into engagement with the forks, so that continued lifting and tipping of the Eurocart causes its lid to open for emptying purposes.

Normally, the charge box will be emptied by use of the compacting means, which comprises the conventional independently operable paddle and slider compaction blade on which the paddle blade is mounted, each time a container is emptied into it, and this provides a convenient means of ensuring that the forked arms 46 are retracted to the safe position before the next container, which may be a large container, is lifted and tipped.

Thus, referring to Figure 5, the slider compaction blade is referenced 52 and the paddle blade 54. A projecting lug 56 is provided on the slider compaction blade whereby, as this blade descends during a charge box emptying procedure, the lug engages a part of the forked arm assembly, generally referenced 58 in Figure 5, to cause this assembly to be retracted into the inoperative safe position.

Like the small container lift and tip bracket arms, in the above-described arrangement the large container lift and tip means, the paddle blade and the slider compaction blade are all operable by individual hydraulic drives tapped into the main vehicle hydraulics. In order to avoid misuse of the rear end loader facilities, as far as is practicable, the hydraulic drives are controllable in the manner described below, wherein reference is made to Figure 5 and Figure 6.

The paddle blade and small container lift and tip drives are controllable by a first handle 60. This handle 60 has two positions 62 and 64, respectively for on/off control of the hydraulic drive circuit to the bracket arm rams shown in Figures 1 and 2 and for control of the hydraulic drive circuit to the paddle blade shown in Figure 5. For this purpose, the handle 60 controls diverter valve 65.

Simultaneous operation of both drives, which could cause damage, is thereby prevented. Second and third handles 66 and 68 respectively control the hydraulic drive circuits for the slider compaction blade 52 shown in Figure 5 and the large skip tip and lift, which is substantially conventional except for operation by hydraulic power.

A first dump valve 70 (Figure 5) is located at the top of the path of movement of the slider compaction blade, and is connected in the hydraulic drive circuit to the small container lift bracket arms. Thus, a small container cannot be lifted and tipped unless the slider compaction blade is in its uppermost rest position. A second dump valve 72 (Figure 5) is located adjacent the bracket arm lifting means for small containers, generally referenced 74 in this figure, and is connected in the hydraulic drive circuit for the slider compaction blade 52, whereby the slider compaction blade cannot be operated if the small container lift is in operation. This ensures that damage cannot be caused by simultaneous operation of the small container lift and tip means and of the slider compaction blade. In this respect, the large container (skip) lift and tip means does not give rise to any problem provided, as above-described, it is ensured that the lid opening forks for Eurocart emptying are retracted.

Various modifications of the above-described arrangement are possible within the scope of the invention hereinbefore defined.

Claims (12)

Claims

1. A waste disposal vehicle of the kind described, wherein the rear end loader is equipped with retractable lifting brackets for small wheeled containers, said lifting brackets having, respectively at differing heights and differing distances from the rear end loader when the arms are extended rearwardly for picking up such containers, first hooking means for engagement with a Eurocart and second hooking means for engagement with an alternative bin.

2. A vehicle according to claim 1, wherein the first hooking means is adapted to engage the lifting lugs provided for this purpose on opposite sides of a Eurocart, and the second hooking means, at the lower level and lesser distance in the rearward direction when the brackets are extended for lifting, is adapted to clasp the handles conventionally provided at opposite sides of an alternative bin to enable manual emptying thereof.

3. A vehicle according to claim 2, wherein, when a Eurocart is lifted, the container is also tipped and lugs associated with the spring loaded lid on opposite sides of the container are brought into engagement with a pair of spaced fork means mounted in the rear end loader, whereby continued movement of the lifting brackets causes the lid of the Eurocart to open.

4. A vehicle according to claim 1 or claim 2 or claim 3, wherein the compacting means consists of a paddle blade pivotally mounted on a slider compaction blade, the paddle blade and the slider compaction blade being independently operable.

5. A vehicle according to claim 4 when appendant to claim 3, wherein, in order to prevent fouling during subsequent operations, the fork means are linked together for retractable movement about a horizontal pivot axis, said linked fork means having a projecting limb which is engaged by the slider compaction blade on descent thereof when the compactor means is used, thereby to cause the fork means to retract to a safe position.

6. A vehicle according to claim 5, wherein a handle is provided for manually restoring the forks to the operative position, for use when the next container to be emptied is a Eurocart.

7. A vehicle in accordance with any of claims 1 to 6, wherein all the rear loader facilities, i.e. large container lift and tip, small container lift and tip, and the compaction means, are hydraulically driven.

8. A vehicle in accordance with claim 7, wherein the bulk storage container on the vehicle chassis is emptied by tipping said bulk storage container.

9. A vehicle according to claim 8, wherein hydraulic drives for tipping and for lifting away the rear end loader are interlinked so that the rear end loader has to be lifted away prior to tipping, so that risk of damage to the rear end loader, which otherwise would strike the ground, is avoided.

10. A vehicle in accordance with claim 7 or claim 8 or claim 9, wherein three control handles are provided for the rear end loader hydraulically operated facilities, the first being a two position handle which operates in con junction with a diverter valve to enable operation of either the small container lift ana tip or pivotal movement of the paddle blade of the compacting means, the second being for operation of the slider compaction blade and the third being for operation cf a large container lift.

11. A vehicle in accordance with claim 10, wherein a first dump valve is provided at the top of the path of movement of the slider compaction blade and a second dump valve is provided adjacent the small container lift bracket means, it being necessary for the first dump valve to be closed, i.e. the slider compaction blade must be in its top rest position, to enable the small container lift and tip to be used, and for the second dump valve to be closed, i.e.

small container lift bracket means fully retracted, to enable use of the slider compaction blade.

12. A waste disposal vehicle substantially as hereinbefore described with reference to the accompanying drawings.