GB2158420A - Waste transfer packer - Google Patents

Abstract

A waste transfer packer for delivering and compressing material such as domestic refuse into a transfer container 10 has a horizontally reciprocable ram 4 operating in a delivery spigot 8. An intermediate, upwardly directed, channel 16 is located between the feed or hopper 1 and the front face of the spigot, into which the less dense material can move so as to fall in front of the ram on its next stroke. The cross sectional area of the channel is one quarter to one half that of the chute. A deflector 13 may be provided in the chute to cause some of the less dense material to move up its slope as the ram moves forwards and thus circulated back into the stream of material moving into the path of the ram. <IMAGE>

Description

SPECIFICATION Waste transfer packers This invention is concerned with transfer apparatus in which domestic or other waste is loaded, having been delivered to a transfer location by collecting vehicles, into larger transfer containers for transit to a distant site.

Such transfer apparatus employs a so-called packer which has a feed chute or hopper in which waste descends by gravity on to the top of a horizontally reciprocable ram operating to eject the waste under pressure through a hollow spigot or register which is arranged to enter an aperture in a wall of the transfer container. The ram has to have considerable clearance in the spigot on its upper side to prevent blockages by permitting large articles that project upwards beyond the margin of the ram to pass through.

A difficulty that has been experienced in the operation of such apparatus is that there is a tendency for lighter and dryer portions of the waste to be carried forward on top of the ram and then to rise inside the container forming an upper layer of low density so that less than optimum use is made of the container capacity.

According to the invention a transfer packer has a feed chute or hopper for delivering waste to the front of a reciprocable ram in its withdrawn or rearwards position, a hollow delivery spigot into which the ram moves forward to compress and deliver waste into a container through a wall of which the spigot projects, and an upwardly directed channel between the feed chute or hopper and the spigot. The effect of providing this channel is to permit material, during the forward stroke of the ram, to move up into it relatively freely, so that it takes this path in preference to continuing through to the container on the top surface of the ram, and so that on the next stroke of the ram it can fall back into the path of the ram so as to be subject to the full compressive effect.

According to a further feature of the invention the bottom of the chute is provided with a rearwardly directed deflector plate, and the opposite face of the chute is preferably also directed rearwardly in a matching manner.

This encourages the recirculation of some of the lighter material in the area above the deflector plate which also contributes to its ultimate positioning in front of the ram, rather than on top of it.

An example of the invention is shown in the accompanying drawing in which is shown a sectional side elevation, schematically represented, of the relevant parts of a packer and a vehicle container.

In the drawing a feed chute 1 is arranged below the upper delivery point of an elevating conveyor 2 which carries waste from a discharge point (not shown) where collecting vehicles can discharge waste. The cross section of the chute 1 is typically 1.5 m square for a domestic waste transfer operation. The chute discharges into a chamber 3 in which a rectangular-faced ram 4 can be reciprocated horizontally by a hydraulic actuator 5. The ram 4 has a rear apron 6 flush with its upper edge. The forward stroke of the ram commences with its forward face in line with the rear wall 7 of the chamber 3.The front of the chamber 3 terminates in a spigot 8 which can extend into a lower loading opening in the rear door 9 of a container 1 0. The loading opening may be closeable by doors of the form described in our co-pending application No. 8228126 which are opened automatically by the entry of the spigot. As the ram 4 moves forward it carries with it waste material that has dropped down in front of it and forces this material into the container 10 along its floor. Continued reciprocation of the ram 4 gradually fills the container and the force exerted by the ram is increased as the container becomes full so that a dense load is obtained to optimise the utilisation of the container and its carrying vehicle.

There is a space left above the ram 4, between it and the upper margin or breaker bar of the spigot 8. This space is necessary on account of the diversity of size and nature of the make-up of the waste material, which, even though pre-sorted to some extent, may contain anything from tea-leaves to old bicycles. It is inevitable, therefore, that a portion of the waste material will be carried through on the top surface of the ram 4 constituted by the apron 6 which is provided to prevent waste getting behind the ram. This portion of the waste material will be substantially unaffected by the compressive action of the ram, and while the denser parts of it will not create much problem, the lighter parts will tend to rise inside the container and form a loose rear wall 1 2 of the material therein.This has the disadvantage that the container cannot be filled to its optimum capacity and it can also interfere with the proper operation of the doors of the container.

The invention provides at the bottom of the chute 1 a deflector 1 3 which slopes upwardly and forwardly to meet the front chute wall, and in addition the rear wall of the chute may be curved rearwardly as shown at 14. Then when the ram 4 is operated some at least of the lighter material will be caused, as the ram moves forward, to move back up the slope of the deflector 1 3 and gradually to circulate back into the stream of waste material moving down into the path of the ram.

The deflector 1 3 may be hinged along its top edge and adjustably supported by a strut 1 5 which may be in the form of a hydraulic cylinder. The strut may incorporate a resilient connection so that the deflector can move somewhat in response to impact to solid articles.

In addition to the deflector 1 3 there is provided between the chute 1 and the spigot 8 an upwardly directed channel 1 6. This is conveniently of about a quarter or a half of the cross sectional area of the chute 1. Thus it may be about 1.5 m wide (it is preferably the same width as the chute) and between 0.38 and 0.75 from front to back. This provides a path of low resistance for material carried forward on the top of the ram. Where such material is of low density it will flow up into this channel, on the forward stroke of the ram, where it will remain until the ram is withdrawn, when it will drop into position in front of the ram ready for the next charging and compacting stroke. Any material that is too heavy to flow upwards into the channel 1 6 may be carried through into the container 10 but since it is of high density it is unlikely to create a problem because it will take up a low position in the container and be subject to subsequent compacting strokes of the ram.

Although the invention is specially suited to operation in conjunction with container doors that are opened automatically by contact with the packer spigot, as described in our copending application No. 8228126, it is also useful in connection with manually opened doors, since it results in the creation of a more compact and predictable shape of the rear wall of waste within the container, so that even without the automatic doors, the quantity of spillage that occurs when the container moves away from the packer is much reduced.

Claims (5)

1. A transfer packer having a feed chute or hopper for delivering waste material to the front of a horizontally reciprocable ram in its withdrawn or rearwards position, and a hollow delivery spigot into which the ram moves forward to compress and deliver waste into a container through a wall of which the spigot is adapted to project, characterised by the provision of an upwardly directed channel between the feed chute or hopper and the forward face of the spigot.

2. A packer according to claim 1 wherein the forwardly located wall of the chute or hopper terminates in a rearwardly directed deflector plate.

3. A packer according to claim 2 wherein the angle to the vertical of the deflector plate is adjustable.

4. A packer according to claim 2 or claim 3 wherein the lower portion of the corresponding rear wall of the chute or hopper is rearwardly directed.

5. A packer substantially as herein described with reference to the drawing.