GB2065195A

GB2065195A - Improvements in or relating to trench-digging machines

Info

Publication number: GB2065195A
Application number: GB7943750A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-04-24
Filing date: 1979-12-19
Publication date: 1981-06-24
Also published as: GB2065195B; AU5404279A; NL7908843A; IT7983499A0; BE880907A; SE7910676L; CH634718A5; IT1126165B; BR7908574A; DE2950009A1; CA1128558A

Abstract

This invention relates to trench- digging machines for draining and irrigating soils. The machine has a chassis 2 on which are mounted transmission means 5 and 6 driven by the motive power of a tractor. The chassis has a horizontal ski 31 mounted therebeneath to regulate the depth of the trench dug by a vertical rotating disc 15 which carries cutters 17 and if desired shovels 18 on its circumference. This disc 15 throws the earth on to a curved vertical deflector 37 and two small surfacing discs are rotatably mounted at the rear of the chassis for movement of the vertical plane. <IMAGE>

Description

SPECIFICATION Improvements in or relating to trench-digging machines The present invention relates to simple, light machines for digging trenches in order to drain and dry soils, and more particularly agricultural land.

In order to save crops sown on low-lying land, farmers usually have to dig trenches in order to dry the land, thus preventing the said seeds from rotting.

The same action is necessary to prevent torrential rains from gullying sloping land.

These trenches are dug either with pick-axes - which makes for really hard work - or with a plough, but the latter builds up a heap of earth on one side, which more often than not covers up the sown furrow lying next to the trench. Trenches dug in this way are irregular and tend to fill rapidly in bad weather.

It is an object of the invention to obviate or minimise these drawbacks, and accordingly consists in a trench-digging machine for draining and irrigating soils, having a chassis on which are mounted transmission gears driven by the motive power of a tractor, said chassis having a horizontal ski mounted therebeneath to regularize the depth of the trench dug by a vertical rotating disc bearing cutters and, in appropriate cases, shovels mounted on its circumference, said large disc throwing the earth on to a curved vertical deflector, and two small surfacing discs being rotatably mounted at the rear of the chassis for movement in a vertical plane.

Machines according to the invention are capable of digging deep, narrow trenches between two sown furrows without building up any parallel heap of earth. Furthermore, such machines do not damage surrounding crops, and provide the trenches with firm sides enabling them to last out a whole season without further work.

The machine may have a chassis borne by the three attachment points of a tractor and on which are mounted all the transmission gears. These gears, driven by the motive power of the tractor, convey a rotary motion to a vertical tracingcutting-shovelling disc. The latter rotates in a contrary motion to the tractor's wheels, throwing the earth and stones on to a deflector which breaks up the earth into small fragments and deflects it, thus causing it to spread over a minimum width of two metres. The depth of the trench is controlled by a ski mounted lengthwise along the tracing-shovelling disc.

A pulley is preferably provided to tighten the belts driving the rotary axle of the tracing disc. The pressure of the pulley is maintained by means of a spring which allows the belts to slip when the tracing disc comes across a stone or a root.

In another embodiment of the invention, the machine may have a second ski mounted parallel to the first.

In another preferred embodiment of the invention, the machine could have a second tracing disc with a deflector mounted on the other side of the chasis, in order to dig two trenches simultaneously.

Various other characteristics and advantages of the present invention will be apparent from the following description taken in connection with the accompanying drawings, which illustrate, by way of example, one possible embodiment of the machine, and in which Fig. 1 is a plan view of the whole machine without its protective casing, Fig. 2 is a side elevation of the machine taken from the side of the gears, Fig. 3 is a side elevation of the machine taken from the side of the disc and deflector, Fig. 4 shows the detail of a cutter attachment on the disc, Fig. 5 shows the detail of a shovel attachment on the tracing disc, Fig. 6 shows a preferred embodiment of the disc cutters, Fig. 7 shows the positions of the cutters drawn on Fig. 6 along the rim of the large tracing disc, and Fig. 8 shows a side view of a cutter on the tracing disc as it rotates in the direction shown by arrow B on Fig. 7, Fig. 9 is a sectional view taken along line A-A of Fig. 10, and Fig. 10 shows a mode of assembly of the small surfacing discs with their driving gear on the chassis of the machine.

With reference to the accompanying drawings, the machine comprises a rectangular chassis 2 borne by the three attachment points 1 of the tractor, the motive power 3 of the latter drives the series assembly made up of a cardan joint 6, which drives a bevel gear protected by a casing 7.

The bevel gear drives a transverse shaft 8 which is mounted on the chassis by means of bearings 9, shaft 8 bears a two- or three-groove pulley 10 driving belts 11 which transmit the rotary motion to a shaft 12, parallel to shaft 8, by means of a pulley 13. Shaft 12 is kept in position on the chassis by means of bearings 14 and its two extremities extend beyond the sides of the chassis, one of them bearing the tracing-shovelling disc 1 5, the other one a regulating fly-wheel 1 6. The latter counteracts the inertia of the shovelling disc and spreads the loads on bearings 14, thus minimising wear of the roller bearings. The tracing-shovelling disc carries four cutters 1 7 and four shovels 1 8 spaced alternately at regular intervals along the circumference of the disc.

Cutters 17 are mounted by means of a support 19, nuts 24 and bolts 25 on to the disc, alternately on its inner side 20 and its outer side 21. Cutters 1 7 are made up of a blade 22 in the shape of a 450 curve 23 towards circular disc 1 5.

Shovels 1 8 consist of a thick rectangular part 33 closely fitted round the rim of disc 1 5. Belts 11 have a tightening pulley 26 mounted on an axle 27 pivoting on its two extremities by means of roller bearings 28. Each roller bearing 28 is mounted at the upper end of a flat bar 29 whose lower end 34 pivots on chassis 2. A helical spring 30, connecting chassis 2 to axle 27, maintains pressure on belts 11. A ski 31 mounted lengthwise parallel to tracing disc 1 5 is situated under the machine, the front part being fixed by means of a rotary attachment 35 and the rear being fixed by means of a vertical flat bar 36 having several holes along it.These holes make it possible to regulate the depth of the trenches by bringing two holes of the flat bar into position in front of the holes provided for the purpose on the chassis, the whole being secured by a locking pin.

A deflector 37 mounted along side disc 15 and extending forward beyond it shifts the earth sideways. This deflector is curved outward at point 38. Two stabilizing feet 39, adjustable vertically, are provided on the opposite side to the tracing disc in order to balance the machine at rest.

For work on stony land the four cutters 17 and the four shovels 18 mounted on disc 15 do not make it possible to dig trenches; so the disc only tears improved cutters as shown in Figs. 6, 7 and 8.

Cutters 40 are mounted alternately on either side of the circumference of disc 1 5. A block 41, preferably of parallelepipedal form, is placed between disc 1 5 and cutter 40 in such a way that block 41 forms an angle 42 secant to the circumference of disc 1 5.

Thus, block 41 forms a constricted space between the side of angle 42 and the back part 44 of cutter 40. Disc 15, rotating in the direction indicated by arrow B ejects the earth caught in the constricted space of cutters 40 on to deflector 37.

Cutters 40 have a cutting edge 43 and a back part 44 forming a constricted space.

For the surfacing of the upper layer of the trench sides in crumbly soils, two small surfacing discs are mounted at the back of the chassis in a straight line with the large tracing disc.

As shown on Figs. 4 and 9, transverse axle 12 mounted on the sides 2 of the chassis drives the surfacing discs 45 from one of its extremities by means of transmission elements mounted in the following way: axle 12 drives a belt 46 which conveys the movement to an axle 47 by means of a pulley 48 and a cardan joint 49, and axle 47 conveys the movement to a shaft 50 bearing the two discs 45 through cardan joints 51. Shaft 50 is parallel to the back of the chassis and moves in the vertical plane thanks to an arm 52 mounted on chassis 2 at point 53 by means of any appropriate hinge-joint.

The small discs 45 carried by shaft 50 are opposed in such a way that their convex sides bear upon the sides of the trench and surface them; a spring 54 mounted on said shaft 50 keeps discs 45 apart. To enable the discs to move on the horizontal plane, they are provided with a central square opening slightly wider than the square section of shaft 50. A screw 55 mounted at the end of shaft 50 keeps discs 45 in position on the latter.

The machine disclosed in the present invention can be used to dig trenches across sown land and to irrigate crops.

It may also be used to dig narrow trenches along the roads.

Claims

1. A trench-digging machine for draining and irrigating soils, having a chassis on which are mounted transmission gears driven by the motive power of a tractor, said chassis having a horizontal ski mounted therebeneath to regularize the depth of the trench dug by a vertical rotating disc bearing cutters and, in appropriate cases, shovels mounted on its circumference, said large disc throwing the earth on to a curved vertical deflector, and two small surfacing discs being rotatably mounted at the rear of the chassis for movement in a vertical plane.

2. A trench-digging machine as claimed in claim 1, wherein a parallelelepipedal block is mounted between the disc and the cutter and forms a secant angle with the circumference.

3. A trench-digging machine as claimed in claim 1 or 2, wherein the curved front part of the cutter is further away from the disc than the back part thereof.

4. A trench-digging machine as claimed in claim 1 , wherein the shovels, consisting of a rectangular part, are closely fitted round the rim of the tracing disc.

5. A trench-digging machine as claimed in claim 1 , wherein the horizontal ski is supported in front by means of a rotatable attachment and at the back by means of a vertical iron bar provided with holes in order to control the depth of the trench.

6. A trench-digging machine as claimed in claim 1, wherein two surfacing discs are mounted on a shaft and opposed in such a way as to have their convex sides against the sides of the trench.

7. A trench-digging machine as claimed in claim 1 or 6, wherein a spring is mounted between the surfacing discs.

8. A trench-digging machine as claimed in claim 1, 6 or 7, the discs are actuated in the vertical plane by means of an axle pivoting on the chassis.

9. A trench-digging machine as claimed in claim 1, wherein the axle bearing the tracing disc receives a counteracting fly-wheel at the other end.

10. A trench-digging machine substantially as hereinbefore described with reference to the accompanying drawings.