GB2337216A

GB2337216A - Soil sifting drum

Info

Publication number: GB2337216A
Application number: GB9810097A
Authority: GB
Inventors: Michael Corcoran
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-05-13
Filing date: 1998-05-13
Publication date: 1999-11-17
Also published as: EP0972435A3; EP0972435A2; GB9810097D0

Abstract

The soil sifting drum (trommel; Figure 1) comprises an inclined rotatable mesh cylinder, the upper end of which is open to be fed with soil, perhaps from a hopper. At its lower end the bottom plate B comprises a shallow helix of 450‹ which causes oversized rejects to be retained in the drum during normal rotation, but which permits said rejects to be discharged if the drum is rotated in the opposite direction. Optionally baffles are fitted inside the drum to increase residence time, and the meshes can be changed for different grading operations. The drum is mounted on a chassis with two wheels, and is driven either by a hand crank, or by a motor (electric or petrol).

Description

1 Soil sifting device The invention relates to a soil sifting device.

2337216 Gardeners would traditionally prepare the soil for cultivation by removing grass first and then turn over the earth breaking the compacted earth into smaller pieces.

The action of breaking these clods down allows the soil to be permeable to both air and water for healthy growth. As a finishing operation the gardener may use a garden riddle to remove stones and weeds. This riddle is a hand held tray made of wood and a perforated material that is shaken back and forth, this has the effect of loosening the soil, so the rocks and weeds are left in the tray. This is a back-breaking and labour intensive job.

According to the present invention the'soil siftacan process soil dug directly from the garden, separating the stones and vegetable matter as quickly as a man can feed the device with material.

The present invention comprises a fabricated mesh drum, a frame holding the drum at an inclined angle, an electric / petrol motor or hand crank, with a means of releasing sifted-out material and a mechanism to deliver sifted soil and debris separately to a barrow or other container.

The inclined drum with open end uppermost is loaded with garden material to be sifted. The bottom end of the drum is closed except for a labyrinth formed by way of a helical (thread like) surface whose ends overlap by a quarter turn. The gap is a result of the pitch of the helix (150 30Omm). On rotating the drum in one direction the soil 1 material is agitated and separated, allowing fine, broken soil to fall through the mesh walls of the drum, while the larger debris is retained.

By reversing the direction of rotation of the drum the helical back plate actively draws the debris out of the bottom end of the tube, delivering it directly into a barrow or similar container.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing:

Referring to the drawing 'fig 1'the 'soil sifta' comprises:

A. Rotating mesh drum.

C. Motor or Crank Handle. D. Frame.

E. Wheels.

Figure 2 illustrates the helical back plate B. B. Helical Back plate.

1..

Claims

Claims

A soil sifter comprising a rotating mesh drum supported on a frame at an inclined angle and driven round by an electric 1 petrol motor or hand crank.

2 A soil sifter as in Claim 1 wherein the upper end of the cylindrical mesh drum is open for insertion of 'rough' soil.

3 A soil sifter as in Claim 1 wherein the bottom end of the drum is closed except for an exit labyrinth formed by way of a helical (thread like) surface whose ends overlap by a quarter turn. The labyrinth is created by the pitch of the helix (150 - 30Omm).

4 The inclined mesh drum with open end uppermost is loaded with garden material to be sifted. On rotating the drum in one direction the soil / material is agitated and separated, allowing fine, broken soil to fall through the mesh walls of the drum, while the larger debris is retai ned.

By reversing the direction of rotation of the drum the helical back plate actively draws the debris out of the bottom end of the tube, delivering it directly into a barrow or similar container.

A soil sifter as in Claim 1 wherein the inside of the tube is fitted with blades to assist in the breaking up of clods of earth.

7 8 9 11 12 13 A soil sifter as in Claim 1 wherein the inside of the tube is fitted with baffles to prevent soil failing directly through the tube without being processed.

A soil sifter as in Claim 1 wherein the tube is angled to assist the soil to move down the tube.

A soil sifter as in Claim 1 where the speed of rotation is from 60 rpm to 100 rpm.

A soil sifter as in Claim 1 wherein the mesh size can be adjusted.

A soil sifter as in Claim 1 wherein the mesh tube has diffierent perforation size options.

A soil sifter as in Claim 1 where the operator can choose to allow the non sifted material to escape the tube.

A soil sifter as claimed in any preceding claims wherein the mechanism is fitted with a loading hopper.

A soil sifter as claimed in any preceding claims wherein the mechanism is fitted with a platform that holds the sifted soil.

2) 14 A soil sifter as claimed in any preceding claims wherein the mechanism is fitted with a shute that transports debris.

A soil sifter as claimed in any preceding claims wherein the mechanism is fitted with a shute that transports sifted soil.

16 A soil sifter as claimed in any preceding claims wherein the mechanism is manoeuvred by means of two wheels.

-114 Amendments to the claims have been filed as follows A soil sifter comprising a rotating mesh drum wherein the bottom end of the inclined drum is closed except for an exit labyrinth formed by way of a helical (thread like) surface the ends of which overlap by more than 4Y.

A soil sifter as in Claim 1 wherein the labyrinth is created by the pitch of the helix.

A soil sifter as in Claim 1 wherein the rotation of the drum in one direction agitates and separates allowing sifted soil to fall through the mesh walls of the drum. Reversal of the direction of rotation of the drum expels the debris from the lower end of the tube into a barrow or similar container.

A soil sifter as in claim 1 comprising a rotating mesh drum supported on a frame at an inclined angle and driven round by an electric / petrol motor or hand cranked ad either end.

A soil sifter as in Claim 1 wherein the upper end of the cylindrical mesh drum is open for insertion of soil & debris mixture.

6 A soil sifter as in Claim 1 wherein the inside of the tube is fitted with blades to assist in the breaking up of clods of earth.

7 A soil sifter as in Claim 1 wherein the tube axis is angled to assist the soil to move down the tube.

8 A soil sifter as in Claim 1 where the speed of rotation is from 10 rpm to 100 rpm.

9 A soil sifter as in Claim 1 wherein the mesh size can be adjusted.