AU747653B2 - Improved waste compactor - Google Patents

Description

WO 00/05136 PCT/AU99/00592 -1- IMPROVED WASTE COMPACTOR INTRODUCTION TO INVENTION This invention relates to waste or garbage compacting devices and in particular, to compacting devices which are highly suited to residential or high density situations where large quantities of domestic type garbage must be processed utilizing minimal floor space.

BACKGROUND OF INVENTION Domestic waste disposal often involves the processing of quantities of low density material which necessarily exhibits a high volume to weight ratio. Such low density material introduces many inefficiencies into the waste disposal process; beginning with a high volume of raw material which necessitates the use of bulky high volume collecting receptacles. Secondly the bulky raw material must be transported for processing or disposal and the high volume of raw material necessitates high volume handling vehicles and if the raw material is to be buried then the high volume adds to landfall and environmental stress.

Many industrial situations which generate waste incorporate compactors as part of their waste disposal regime thereby reducing waste bulk and decreasing the cost of waste disposal. Such waste compactors are commonly used and come in a variety of designs which are readily adaptable to numerous industrial situations.

Industrial compactors are generally very heavy duty units of dedicated design, often bulky per se and adapted for specific waste types generated by the industry in question.

Domestic waste generation in contrast involves many individual contributors and a range of bulky low toxicity waste where only rarely would an individual generate enough waste to justify the cost of a waste compactor.

However, the totality of domestic waste makes a substantial contribution to community waste generation and in situations of residential high density living where many individuals live in close proximity and can share common services; for example high rise units, apartments etc, waste compactors represent an efficient means of reducing waste bulk.

WO 00/05136 PCT/AU99/00592 -2- Furthermore, large public events which can be held at stadiums etc also give rise to waste disposal problems of a similar nature where a high volume of people are located in a limited space. Such public events often exacerbate waste generation by the mass consumption of takeaway and pre-packaged goods and other products.

To date, compactors available for use in residential high density situations are either free standing units or units which co-operate with a buildings waste chute. The free standing units require double or triple handling of waste into and out of the compactor and whilst capable of handling and processing very large quantities of waste, such systems require dedicated interaction with the waste collectors to operate efficiently and are not ideal in all situations.

The chute integrated units are designed to receive bagged waste from a common chute and operate by a sliding action flat compacting blade which either compresses the waste directly into waste bins or within a compaction chamber.

The direct compaction method into waste bins is not desirable as it places high stress and load on the bins during compaction thereby increasing bin damage.

Many currently available chamber compaction units also suffer from disadvantages, in particular, the use of flat blades to compact waste encourages the build up of waste awaiting compaction against the blade and during compaction the flat bladed units do not efficiently shut off the input chute which may result in odour build up and projection back into the receiving chute and also increase the risk of fire in the chute in the event of heat generation or explosion during compacting. In addition the length of blade travel and chamber dimensions render such units bulky and costly to produce.

Furthermore, flat blade compactors often rely on the sides of the compaction chamber for guidance of the compaction blade and the necessary tolerances allow waste to bypass the side of the blade resulting in increased odour and hygiene problems as well as accelerated wear.

Accordingly, a need exists of a self-contained compact, safe and hygienic waste compactor adapted for use in high density residential or similar situations where a large quantity of people share a limited space.

PCT/AU99/00592 Received 14 April 2000 -3- STATEMENT OF INVENTION In one aspect, the invention provides a waste compactor including a compaction chamber adapted to co-operate with a waste receiving chute for directing loose waste into said chamber, an ejection door movable from a first closed position forming a floor to said chamber to a second position opening an ejection chute of said chamber and a compaction blade adapted to compact loose waste in said chamber wherein said compaction blade is further provided with an arcuate roof and is pivotally mounted and adapted for arcuate movement from a first withdrawn position to a second position such that the arcuate movement urges said loose waste against said closed ejection door so as to form a compacted waste plug as said blade approaches said second closed position and wherein the closing action of said blade occludes the receiving chute during compaction.

The compaction blade is preferably formed as a scoop having generally sector shaped sides, a curved roof; and a concave face.

The blade may be pivotally mounted opposing the receiving chute and adjacent and preferably contiguous with the ejection door such that the closing action of the blade causes the blade roof to occlude the receiving chute during compaction thereby eliminating any escape of fumes up the receiving chute during compaction.

The blade may have a concave face to assist in the gathering of loose waste and the formation of stable waste plugs in addition to directing waste towards the center of the blade to effect higher compaction.

The ejection door may be slidable between the first and second positions while maintaining the contiguous relationship with the blade pivot region to assist in maintaining the sealing of the compaction chamber during the ejection cycle.

The compactor may include a sensor to detect the accumulation of loose waste in the compaction chamber such that when loose waste has filled the compaction chamber, the compaction cycle starts with the blade rotating about its pivot from the first withdrawn position to the second closed position, returning to the first position to allow more waste to be introduced.

AMENDFn QHF WO 00/05136 PCT/AU99/00592 -4- The compaction blade may be operated by a pair of rams acting on arms which may be external to the compactor or most preferably by a single ram acting on a member which may be internal to the compactor. The compactor may be associated with a bin conveyor or rotating feeder to automatically feed and process waste bins for receiving waste plugs.

The invention will be described in greater detail by reference to the following figures which detail one particularly preferred embodiment of the invention only with cross-sectional views of the compactor and associated receiving chute and bin during various stages of operation.

Figure 1 shows the compactor in a rest position receiving loose waste from the receiving chute.

Figure 2 shows the compaction cycle forming waste plugs.

Figure 3 shows the ejection cycle.

Figure 4 shows the end of the ejection cycle.

DETAILED DESCRIPTION OF INVENTION Figure 1 shows a cross-section side elevation of the improved waste compactor comprising a substantially self-contained compactor unit 14 adapted for positioning with respect to a receiving chute 2. The receiving chute 2 is the disposal route for loose waste 3 delivered by the user and provides a common waste conduit in apartment buildings, large collective residential situations or venues. The waste compactor includes a compaction chamber 1 positioned at one end of the waste compactor unit. The compaction chamber has an opening communicating directly with the receiving chute 2. The compaction chamber is further defined by an ejection door 4 which is positioned toward the bottom of the waste compactor and is moveable from a first closed position shown in Figure 1 forming a floor and therein defining the bottom of the compaction chamber to a second position drawn back from said compaction chamber so as to open an ejection chute 5. The compaction chamber is further defined by the scoop shaped compaction blade 6 which is pivotally mounted opposing the receiving chute opening 15 and contiguous with the slidable ejection door 4. The compaction blade is adapted for arcuate movement from a first withdrawn position defining WO 00/05136 PCT/AU99/00592 the open compaction chamber to a second closed position such that the arcuate movement urges the loose waste in the chamber against the closed ejection door thereby compacting the loose waste into a waste plug 13 (shown in Figure The compaction blade 6 is formed in the shape of a scoop having generally sector shaped sides 7 and a curved roof 8. The compaction blade face 16 is of concave configuration such that the compacting action of the blade serves to gather up the loose waste 3 toward the center of the blade and assist in the formation of a compact self-contained and stable waste plug 13. The junction of the blade face 16 and roof 8 forms a shear point 22 which can interact with a heavy duty plate 23 positioned at the chute opening so as to shear off any waste only partially inside the compaction chamber 1. The compactor blade 6 is pivotally mounted in a position opposing the receiving chute opening 15 such that the closing action of the blade causes the blade roof 8 to traverse the receiving chute opening 15 and thereby occlude the receiving chute during the compaction cycle so as to effect the complete closure and containment of the compaction chamber during the compaction cycle.

Referring to Figure 2, the compaction cycle of the waste compactor is shown where the compaction blade 6 has moved from the first to the second position, compacting the loose waste into a bolus shaped waste plug 13. The curved blade roof 8 can be seen to fully occlude the receiving chute opening and with a combined action of the roof 8, the blade face 16 and the ejection door 4, forming a completely closed compaction chamber 1. The complete closing of the compaction chamber during the compaction cycle ensures that any fumes, gasses or in the case of explosion, fire; are prevented from escaping back up the receiving chute (or into the compactor) and are fully contained within the waste compactor chamber.

Referring now to Figure 3, the ejection cycle of the waste compactor is shown with the retraction of the ejection door 4 by the action of the retraction ram 17. Once the ejection door is slid from underneath the compaction blade 6, the waste plug 13 falls through the ejection chute 5 and into an awaiting waste bin Once the waste plug has fallen from the ejection chute, the ejection door 4 returns WO 00/05136 PCT/AU99/00592 -6to the first position closing the ejection chute and with the return of the compaction blade to the first withdrawn position the receiving chute opening 15 is again opened and any accumulated loose waste can fall into the compaction chamber. The curved blade roof 8 which has occluded the opening 15, allows the accumulation of loose waste during the compaction cycle, if this were to occur, such that withdrawal of the compaction blade does not interfere with the loose waste accumulated which subsequently tumbles into the opened compaction chamber.

In use, the waste compactor would be permanently fitted to the opening of the receiving chute of a residential building or venue probably in the basement or like region thereof and fitted into a position raised above the ground under which could be placed a waste bin 20 or possibly a plurality of waste bins fitted on a bin conveyor 18 or rotary feeder. The waste compactor is designed for fully automated use and would begin its cycle in a rest position shown in Figure 1 with the compaction blade in a first withdrawn position, thereby exposing the chute opening 15 allowing direct communication from the receiving chute 2 to the compaction chamber 1. As loose waste is dropped into the compaction chamber 1, it will gradually build up to a level requiring compaction and this can be detected by the use of photocell or other sensor 19. The sensor could be placed either in the compaction chamber or at the end of the receiving chute 3, such that upon the waste accumulating to a set level, the sensor would be activated causing the compaction blade 6 to begin its arcuate rotation around the blade pivot 9 by the action of the compaction ram 10. The compaction ram is fitted to a member 11 which cooperates with the blade pivot 9. The compaction ram could be fitted internal or external to said waste compactor 14 with the blade pivot 9 acting as an axle to the compaction blade 6. The activation of the compaction blade can be followed through to Figure 2 where the arcuate rotation of the compaction blade and in particular, the concave configuration of the blade face 16, effectively gathers up the loose waste 3 encouraging the formation of a compact and stable waste plug 13. The compaction blade draws the waste across the opening which is occluded as the blade moves from the first position to the second position WO 00/05136 PCT/AU99/00592 -7and draws the loose waste 3 directly against the closed ejection door 4. The compaction blade is pivoted at a position adjacent and contiguous to the ejection door so as to form an effective seal against the door and in combination with the occlusion effect with the curved blade roof, maintains a seal for the whole compaction chamber. The first compaction cycle would be repeated a number of times with the withdrawal of the compaction blade and the further filling of the compaction chamber with more loose waste until the sensor 19 is again activated where the compaction cycle would be repeated. The compaction cycle is repeated until a waste plug of maximum size is formed and no more loose waste can effectively be compacted and then by reference to Figure 3, the ejection door 4 will slide open by the action of the retraction ram 17, thereby allowing the waste plug 13 to fall through the open ejection chute 5 into an awaiting bin 20. Once the waste plug 13 has cleared the ejection chute 5, the ejection door returns to the closed position which can be seen with reference to Figure 4 and the compaction blade again returns to its first withdrawn position.

The automated action of the waste compactor can take full advantage of bin conveyancing via a conveyor 18 or rotary feeder and with suitable sensors, a plurality of bins can be made to traverse the waste compactor automatically accumulating the optimum amount of waste with the minimum of operator attention.

The various features of the improved waste compactor provide for the efficient and safe processing of domestic non-toxic waste which are particularly adapted for use in high density residential situations or public events, large venues etc. where a large quantity of loose domestic waste requires processing. The waste compactor of the invention is totally self-contained, thereby minimising the potential for gas or odour escape and further minimising the possibility of fire or explosive damage and moreover, provides for totally contained compacting without exposing the waste bin to any form of pressure or undue physical forces.

Furthermore, the waste compactor of the invention is well adapted for full automation facilities including the use of automatic bin feed conveyors which can be easily monitored by counting the number of waste plugs falling into a given bin WO 00/05136 PCT/AU99/00592 -8and allowing efficient handling of waste bins. The particular configuration of the compactor blade minimises the build up of loose waste in the compaction chamber prior to formation of the waste plug as the waste will not sit beside the compaction blade awaiting compaction as is the case in the larger sliding blade units. In addition, the efficient operation of the waste compactor of the invention allows it to handle relatively small batches of loose waste with the formation of a quick succession of waste plugs without a need to provide a very large compaction chamber which is only sporadically activated thereby minimising the formation of odours. Furthermore, the waste compactor of the invention has a particular blade configuration and action which ensures that the unit always closes off the receiving chute so as to prevent the risk of any fire transfer or odour transmission up the receiving chute. The curved blade face is self-cleaning and the pivoting action minimises blade travel with a minimum of waste build up against the blade providing a highly efficient waste compacting unit which is readily adapted to vertical or horizontal access to receiving chutes. Furthermore, the pivotal action of the compaction blade minimises sideward forces on the walls of the compaction chamber thereby allowing the compactor to operate with smaller clearances. The greater precision available allows the compactor to minimise waste loss bypassing up the sides of the blade during compaction. Conventional slide blades run in the compaction chamber and use the side walls as a guide which requires greater working clearances which can trap waste. In addition, the shorter ram stroke required to operate the pivoted compaction blade of the invention requires less hydraulic oil flow and thereby reduces power requirements and costs.

Claims (8)

1. A waste compactor including a compaction chamber adapted to co-operate with a waste receiving chute for directing loose waste into said chamber, an ejection door movable from a first closed position forming a floor to said chamber to a second position opening an ejection chute of said chamber and a compaction blade adapted to compact loose waste in said chamber wherein said compaction blade is further provided with an arcuate roof and is pivotally mounted and adapted for arcuate movement from a first withdrawn position to a second position such that the arcuate movement urges said loose waste against said closed ejection door so as to form a compacted waste plug as said blade approaches said second closed position and wherein the closing action of said blade occludes the receiving chute during compaction.

2. A waste compactor according to claim 1 wherein said blade is pivoted coincident to and in a generally tangential plane to said concave blade face.

3. A waste compactor according to any one of claims 1 or 2 wherein said compaction blade is generally scoop shaped with sector shaped sides such that the arc of said sector is co-axial with the pivot of said blade.

4. A waste compactor according to any one of claims 1 to 3 wherein said blade is mounted opposite said receiving chute and adjacent said ejection door.

5. A waste compactor according to claim 4 wherein said blade is mounted contiguous to said ejection door.

6. A waste compactor according to any one of claims 1 to 5 wherein said ejection door is slidable between said first and second positions while maintaining the contiguous relationship with the blade.

7. A waste compactor according to any one of claims 1 to 6 further including a sensor to detect the accumulation of loose waste in said compaction chamber and activate a compaction cycle with said blade rotating about its pivot from the first withdrawn position to the second closed position and returning to the first position to allow more waste to be introduced with said compaction chamber.

8. A waste compactor according to any one of claims 1 to 9 substantially as hereinbefore described with particular reference to the examples. 11 AMENUD, :-EET IPE4Ai