Device and method for loosening soil

Abstract

A device and method for loosening compacted soil, a plurality of tubular devices made from a resiliently compressible material having a hollow hub with a series of radially and circumferentially curving blades extending from the hub, a plurality of devices arranged in an array in soil to cause loosening of the soil as it seasonally expands and contracts and causes compression and subsequent expansion of the devices which in turn loosens the soil sufficiently to aerate the soil.

Claims

1. A ground soil loosening device including an elongated tubular hub having a series of circumferentially spaced apart blades extending all around said tubular hub, each blade in said series having an inner end affixed to said hub and extending along the length of said hub and projecting radially out from a perimeter of said hub, each of said blades having an outer portion continuously curving circumferentially in the same direction towards an outer portion of a next adjacent blade in said series, said blades formed from a resiliently deflectable material so that said outer portion of each of said blades is resiliently deflected radially inwardly by a seasonal increase of ground soil pressure exterted thereon when said device is buried in said ground soil to cause said outer portions of said blades to be moved radially inwardly and to thereafter move back radially out when said ground soil pressure decreases.

2. The ground soil loosening device according to claim 1 wherein said hub has a lengthwise slot extending through a tubular wall of said hub defining said perimeter thereof to allow said tubular wall of said hub to also be resiliently moved radially inwardly by an increase in ground soil pressure.

3. The ground soil loosening device according to claim 1 wherein said resiliently bendable material comprises polyethylene plastic.

4. The ground soil loosening device according to claim 1 wherein a cap is installed closing off said hub and blades of said device at a top end of said device.

5. The ground soil loosening device according to claim 2 wherein said blades are thinner than said wall of said hub.

6. The ground soil loosening device according to claim 1 wherein said devices are approximately 43 cm long.

7. The ground soil loosening device according to claim 1 wherein there are a total of eighteen of said curved blades projecting from said perimeter of said hub.

8. The ground soil loosening device according to claim 1 wherein said outer portions of each blade extends circumferentially past said inner end of a next adjacent blade in said series of blades.

9. A method of loosening compacted ground soil comprising installing a plurality of ground soil loosening devices according to claim 1 into ground soil to be loosened by forming an array of vertically extending holes formed in the ground soil to be loosened and inserting each of said devices in a respective hole and thereafter completely covering an upper end of each device.

10. The method of claim 9 wherein said array is in a grid form with said ground soil loosening devices arranged in rows.

11. The method according to claim 9 wherein said ground soil loosening devices are spaced apart a distance of approximately 51 cm.

12. The method according to claim 9 wherein each of said ground soil loosening devices are about 43 cm long.

13. The method according to claim 9 including providing a total of eighteen of said curved blades in each ground soil loosening device.

14. The method according to claim 9 including capping a top end of each ground soil loosening device.

Description

DESCRIPTION OF THE DRAWING FIGURES

(1) FIG. 1 is a sectional view of soil located below the surface of the ground to a substantial depth, and having a plurality of devices according to the invention installed into a respective hole formed in the soil.

(2) FIG. 2 is a diagrammatic plan view of an array of soil loosening devices according to the invention, with the direction of soil loosening movement of the action produced by the devices in the array represented by broken lines.

(3) FIG. 3 is an enlarged fragmented perspective view from the top of a device according to the present invention.

(4) FIG. 3A is an enlarged fragmented perspective view taken from below of a device according to the invention so as to show the bottom end thereof.

(5) FIG. 4 is an enlarged fragmented side view of a device according to the invention.

(6) FIG. 5 is an enlarged bottom end view of the device shown in FIGS. 3, 3A and 4 in an uncompressed state.

(7) FIG. 5A is an enlarged bottom end view of a device according to the invention in a compressed state.

DETAILED DESCRIPTION

(8) In the following detailed description, certain specific terminology will be employed for the sake of clarity and a particular embodiment described in accordance with the requirements of 35 USC 112, but it is to be understood that the same is not intended to be limiting and should not be so construed inasmuch as the invention is capable of taking many forms and variations within the scope of the appended claims.

(9) Referring to the drawings and particularly FIG. 1, a series of elongated generally tubular devices 10 according to the invention is shown, which are each inserted into a respective vertical hole drilled or otherwise formed in the soil.

(10) The soil at the level in which the devices are installed is represented as being in a loosened condition due to the activity of the devices 10 compared to the soil below the level of the bottom of the devices 10 which remains tightly compacted.

(11) The devices 10 may be of a relatively small diameter (i.e., approximately in diameter) and preferably of a short length, i.e., approximately 17 inches long and may be spaced approximately 20 inches apart in the grid array shown in FIG. 2.

(12) The devices 10 have an inner tubular hub 12 from which radially extend a series of identical curved blades 14. The blades 14 are of a thickness and stiffness which allows them to be resiliently compressed as shown in FIG. 5A, preferably integrally formed with the hub 12 and to act to loosen the soil when the soil compression lessens. A thickness of 0.040 inches and radial length of about 0.420 inches has been successfully used. The blades 14 are curved to progressively extend increasingly circumferentially in the same direction as well as decreasingly less radial at the outer ends thereof. The devices 10 may be made from an extruded durable plastic material such as polyethylene plastic which is resiliently compressible and able to withstand being buried in soil for long periods while still able to expand when the soil pressure decreases sufficiently.

(13) The top end of each device 10 is provided with a cap 16 preferably integrally formed together with the other portions of the devices 10 to close off the top so as to prevent soil packing between the blades 14.

(14) The hub 12 wall is thicker than the blades 14 but has a lengthwise extending radially slot 18 extending completely through the wall of the hub 12 in order to allow radial compaction of the hub 12 to increase the overall resilient compaction of the devices 10.

(15) As noted above, the curved blades 14 extend radially and also circumferentially in the same direction. Preferably there is an equal spacing between successive blades 14 as best seen in FIGS. 5 and 5A except that, a blade 14 is absent at the location of the slot 18.

(16) FIG. 5 depicts a bottom view greatly enlarged of a device 10 in its relaxed condition assumed when the surrounding soil is in a reduced compression state.

(17) FIG. 5A shows a device 10 in a compressed state which occurs when the surrounding soil is in a seasonal compressed state.

(18) The curved blades 14 are thereby compressed in both radial and circumferential directions as shown. The hub 12 is also compressed since the slot 18 allows circumferential movement together of the hub 12 wall on either side of a slot 18 as shown in FIG. 5A.

(19) When the soil pressure decreases, the devices 10 will again expand with the blades 14 moving radially out and retracting circumferentially, the hub 12 also expanding slightly due to the slot 18 as seen in FIG. 5.

(20) This expansion of the blades 14 and hub 12 acts on the surrounding soil to loosen the same sufficiently to allow air to infiltrate into the soil

(21) As will be better understood by reference to FIG. 2, the result of the devices 10 being arranged in a grid array creates a varying expansion of the soil in different directions by each device 10. This effect creates a loosening up of the soil which persists during the season when the compression of soil declines enabling atmospheric air to aerate the soil.