Introduction

This invention relates to a composter.

Background of the invention

Composting is an environmentally friendly way of disposing of waste organic material. Generally in order to provide good compost, it is desirable that the material aerobically decomposes. By providing the right environment for aerobic decomposition, the material can quickly decompose and the quality of the compost is improved . It is also desirable to collect leachate which drains from the compositing material for separate use or to dispose of rather than to allow the leachate simply to drain to the ground. Composting containers may come in many shapes and sizes for both domestic and commercial use.

In our earlier patent application WO 2006/037152 we describe a composting apparatus that comprises a plastics container formed of a plurality of segments. The container includes a centrally positioned aerator that allows air from the exterior of the container to

distribute into the compositing mass within the

container. The container also includes a base which included a leachate chamber for collecting leachate that drains from the composting mass during composting.

This apparatus has proved quite successful but it is considered that there is an opportunity to introduce additional air into the container to improve the aerobic compost decomposition. It is this issue that has brought about the present invention .

Summary of the invention

According to one aspect of the present invention there is provided a composter comprising a container for receiving material to be composted, an aerator within the container and at least one opening for allowing air to pass from the aerator into the container, a base

structure defining a floor on which the composting material sits above a leachate tank located under the floor, an air flow path through the base structure for providing air from outside the composter to the aerator and to openings located in the floor above the leachate tank to facilitate aerobic decomposition of the

composting material .

Preferably, the base structure includes a plurality of spaced pillars that support the underside of the floor, the pillars facilitating air flow through the floor. Preferably, the pillars extend upwardly from the base of the leachate tank. In a preferred embodiment each pillar has a cut out in its wall facilitating air flow into the leachate tank.

Description of the drawings

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a composter,

Figure 2 is an exploded perspective view of the composter,

Figure 3 is a cross sectional view of a composter taken through the base of side walls and the lid showing the components slightly separated,

Figure 4 is a plan view of the base with a base plate fitted, Figure 5 is a plan view of the base with the base plate removed, and

Figure 6 is an underside view of the base. Description of the preferred embodiment

The composter 10 shown in the accompanying drawings is in many respects very similar to the composter that is the subject of our co-depending patent application

WO 2006/037152. More particularly, the composter is similar to the embodiment illustrated in Figures 13 and 14 of that application, the disclosure of which is incorporated herein by reference .

The composter 10 shown in Figures 1 and 2

essentially comprises a rectangular container 10 having side walls 11, 12, 13 and 14, a base 30 and a lid 16. The join between the side walls includes an inclined joining panel 17 which gives the composter a more rounded configuration. Mounted centrally of the base 30 is an aerator 20 that extends upwardly into the composting enclosure 19 defined by the container. The side walls and lid of the container are moulded in plastics to define a twin walled hollow configuration as shown in Figure 2 and 3. The container 10, side walls 11-14, lid 16, and aerator 20 are substantially similar to the components disclosed in WO 2006/037152.

This invention relates to the design of the base 30 which is described in greater detail hereunder.

The base 30 as shown in the cross-sectional view of Figure 1 comprises a leachate tank 31 and a leachate tank support structure 32 that is moulded in plastics. The moulding defines a peripheral outer wall 33, an inwardly spaced leachate tank 31 having a peripheral wall 34 spaced inwardly from the outer wall 33 of the base structure 30 and terminated on a level slightly below the 30. The leachate tank 31 has a substantially horizontal base 38 that includes eight equally spaced upstanding pillars 40 that extend upwardly from the base 38. The centre of the tank includes an upwardly projecting frustoconical spigot 45 that in use supports the stem 46 of the aerator 20. The underside of the leachate tank 31 has downwardly projecting feet in the form of an inner ring 51 underneath the aerator and eight annular feet 52 underneath each pillar 40. The top of the base structure 30 between the outer wall 33 and the wall 34 of the tank 31 includes a raised peripheral rib 43 that, in use, engages an external clamping ring 44 that holds the base structure to the base of the wall structure. The join between the top of the base structure and the external rib in the base of the wall structure is shown exploded in Figure 3.

The top of the tank 31 is covered by a substantially planar floor 60 that has a central cut out 61 to

accommodate the frustoconical spigot 45. The floor 60 has a series of perforations 62 allowing air to escape from the tank 31 into the chamber of the composter. As shown in Figure 3 the floor locates on a ledge 64 formed at the top of the outer wall 34 of the tank 31 and an annular shoulder 65 formed on the frustoconical spigot 45. The floor 60 is removable, but serves to separate the composting waste from the leachate tank 31. The floor 60 is also supported by the upper ends of the pillars 40 and four supports 42. The pillars 40 include cut outs 41 in the wall structure allowing air to flow out into the leachate tank 31 above the liquid level to then flow through apertures 62 in the floor 60 into the base of the composting chamber 19. The floor 60 has four outwardly extending webs 66 having spaced parallel slots 68 to allow the leachate to drain onto the tank 31.

The underside of the base 38 of the leachate tank 31 includes a pair of diagonal channels 68, 69 that extend from opposite corners across the centre of the composter. These channels 68, 69 allow air to flow from the exterior of the composter 10 along the channels 66, 67 air into the central aerator 20 as shown in Figure 3. The base of the tank is designed so that there is sufficient ground engaging wall structures to support the structure whilst at the same time facilitate the ready transfer of air for both the aerator and the top of the leachate tank so that it can filter through the base into the bottom of the compositing material.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention