AU633703B2

AU633703B2 - Pasture topping machine

Info

Publication number: AU633703B2
Application number: AU72645/91A
Authority: AU
Inventors: Christopher Grow
Original assignee: CHRIS GROW ENGINEERING Pty Ltd
Current assignee: CHRIS GROW ENGINEERING Pty Ltd
Priority date: 1990-03-08
Filing date: 1991-03-06
Publication date: 1993-02-04
Anticipated expiration: 2011-03-06
Also published as: AU7264591A

Description

r- L_ C- r rb ii 633703 Form COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952-62 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Application Number: Lodged: Class Int. Class Complete Specification Lodged: Accepted: Published: Prioity: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: Address of Applicant: Actuai Inventor: Address for Service: TO BE COMPLETED BY APPLICANT CHRIS GROW ENGINEERING PTY LTD Greenhill Road, Uraidla, South Australia, Australia CHRISTOPHER GROW care of R.K. MADDERN ASSOCIATES, 345 King William Street, Adelaide, South Australia, 5000 Complete Specification for the invention entitled: "PASTUE TOPPING MACHINE" The following statement is a full description of this invention, including the best method of performing it known to me. us.

i-i. This invention relates to a machine which is capable of reducing the height of pasture, and capable of operating at relatively high speed. The invention also relates to a method of topping pasture.

Although cattle eat longer grass than some other animals, nevertheless there is a requirement that the very long fibrous stalks of grass be severed to increase growth of more succulent grass closer to the ground which is more acceptable for cattle. Particularly if the cattle are utilised in the dairy industry, it is desirable to provide a pasture capable of producing milk having a protein/fat ratio within certain limits.

9 @0 "15"0 Rotary slashers are very well known and in common use, but a coco 94.: difficulty which is encountered if a rotary slasher type o machine is utilised for topping cf pasture is that the severed grass tends to bunch and be deposited in lumpy masses *o o which are unpalatable for cattle, and if left on the ground 27 d create areas where the buried pasture will die. It is known to be desirable to have the cut pasture distributed as an even but very thin mat over the pasture as a topping machine traverses the ground. The main object therefore of this Sinvention is to provide an even distribution of severed pasture, and in an embodiment of the invention there is provided a frame having a top plate and two side plates depending from respective side edges of the top plate, driven spindles depending from the top plate, scythe blades .O radiating from lower ends of the spindles and coupled for c eo drive thereto, characterised by a rear portion of the top plate extending upwardly by an amount sufficient to establish a low pressure zone behind the fr.,ie when the machine is mobile in a forward direction.

The method of the invention comprises moving a machine ad defined herein forwardly over pasture, severing the pasture with a scything action by driving said scythe blades rotationally while moving the machine forwardly creating a low air pressure zone rearwardly of the machine, and B14 ng -2-

I

severed pasture cuttings into said low pressure zone by air draft from said blades to effectively disperse the cuttings at the rear of the machine.

i 5 In another aspect of the invention, the topping machine comprises a top plate which slopes upwardly and rearwardly of the cutter blades.

With this invention it is found that a low pressure zone is created rearwardly of the machine and the pasture toppings removed by the machine can be caused to be blown upwardly, rearwardly and outwardly as a widely dispersed suspension in the outflowing air which can be made sufficiently turbulent that there is little likelihood of cohesion or adhesion of the pasture topping to the inner surfaces of the machine.

An embodiment of the invention is described hereunder with reference to and as illustrated in the accompanying sketches in which:p Fig. 1 is a rear elevational perspective of the machine, S Fig. 2 i8 a side elevational perspective of the machine, Fig. 3 is an orthographic side elevation, and Fig. 4 is a partly sectional diagrammatic plan of Fig. 3.

In this embodiment, a pasture topping machine 10 (omprises a 0K frame 11 and two longitudinally extending skid plate Sassemblies 12.

The frame 11 comprises a top plate 13 which has depending flanges 14 which are secured to side plates 15 of the skid plate assemblies 12 by means of bolts 16 which extend through vertically oriented slots 17 in the side plates 15. This provides a means whereby the top plate 13 can vary in height with respect to the skid plate assemblies 12. The rear portion of plate 13 slopes rearwardly and upwardly by an -3- ;~.iil amount sufficient to establish a low pressure zone behind the frame when the machine is mobile in a forward direction.

Each skid plate assembly 12 is provided with a respective skid 20 Which at both its front and rear ends is provided with an upwardly extending curved portion 21, the upper part of which has a much smaller radius of curvature than the lower part so that the portion 21 comprises two merging degrees of curvature. Each skid 20 is provided with a hard metal base, and fully supports the weight of the topping machine during use.

The top plate 13 carries on it a plurality of gear boxes 23, o all there being two such gear boxes in this embodiment but in o0I0.1 other embodiments there can be three or more. The gear boxes 09,00 bos; are arranged to be driven by a shaft assembly which includes o a longitudinally extending input shaft 24 which is, in use, o coupled to a power takeoff shaft of a tractor, and the 00O transversely extending shaft 25, and each output shaft 26 depends from a respective gear box 23 and terminates at its lower end in a plurality of radially extending cutter scythe blades 27, each scythe blade 27 sloping downwardly toward its 00. radially outer end, but each end having a portion 28 sloping upwardly to its trailing edge at 28 in a circumferential direction to its trailing edge. The blades are provided with :o hardened bushes (not shown) which pivot about depending spindlus. As shown in Fig. 4, the forward traverse of the blades 27 is rearward from the front edge of the top plate 13 S09. by a distance sufficient to reduce danger of the blades 9000.

impelling particulate material at sufficient elevation to impinge on a driver of a tractor, and the rearward traverse terminates beneath the rearwardly and upwardly sloping plate 13, so that the plate does not substantially interfere with the discharge of toppings. The forward traverse of each blade is outwardly towards its adjacent side plate.

The forward end of the top plate 13 is provided with a downward return double fold at 31 (Fig. 3) while the rear end is provided with an upper double fold 32, the folds -4functioning as plate stiffeners, and the fold at 31 also directing flow of incoming air downwardly from the front of the machine as best illustrated in Fig. 2. Both the forward and rear ends of the frame are open for air flow there through.

The rearwardly and upwardly sloping portion 21 of the top plate 13 is entirely, or almost entirely rearward of the axis of rotation of the cutter blades 27, and has a short but relatively steep forward portion 34 which, when the vehicle is travelling, assists in creating a low pressure zone r earwardly of the blades 27.

There are also provided a pair of cheek plates 35 hinged at 36 at their forward ends and converging rearwardly. The rearward convergence is adjusted by means of a locking bolt 37 which extends through a circumferential slot 38 near the rear end of top plate 13 as best seen in Fig. 4, and controls the degree of convergence of the cheek plates 35. The cheek plates 35 thus become deflector places which are very useful in controlling the flow of air together with toppings when the machine is in use. The object to be achieved is to maintain the toppinys relatively evenly distributed within the outflowing air.

~2S The forward traverse of rotation of the blades 27 is towards the side plates 15, and is such as to cause an updraught of air as shown in Fig, 3, which is drawn inwardly through the front of the machine, and it has been found that in use the 46 *i updraught is sufficient to lift grass which has been temporarily flattened by the passage over it of the tractor tyres which precede the machine in use, while the cut grass is maintained as an evenly distributed suspension and does not tend to form a windrow.

Typically in use, the machine can be drawn at a speed of about 15km per hour over grass to be topped, with the peripheral speed of the blades exceeding 3000 metres per minute. At that speed, and with the arrangement as r illustrated in the embodiment, the grass topping is extremely efficient and the cut grass is entrained in an outflow of air rearwardly of the machine with little or no build-up of grass toppings against the inner surfaces of the machine.

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Claims

1. A pasture topping machine comprising a frame having a top plate and two side plates depending from respective side edges of the top plate, driven spindles depending from the N top plate, scythe blades radiating from lower ends of the spindles and coupled for drive thereto, characterised by a S rear portion of the top plate extending upwardly by an amount sufficient to establish a low pressure zone behind the frame when tho machine is mobile in a forward direction.

2. A pasture topping machine according to claim 1 further characterised by fasteners operatively located between the side plates and top plate.

3. A pasture topping machine according to claim 1 or claim 2 further characterised by skid plates having upwardly sloping front and rear ends, and extending along lower edges of the side plates.

4. A pasture topping machine according to any preceding claim further characterised in that the rear portion of the top plate slopes upwardly and rearwardly from a front portion, all, or nearly all, the upwardly and rearwardly sloping portion being rear of the spindles.

A pasture topping machine according to any preceding claim further characterised that the forward transverse of the scythe blades is located a distance rearwardly of the front end of the frame.

6. A pasture topping machine according to any preceding claim further characterised in that each scythe blade slopes downwardly towaris its radially outer end, and each radially outer end slopes upwardly in a circumferential direction to its trailing edge.

7. A pasture topping machine further characterised by a pair of cheek plates each located inwardly of an inner surface of a respective said side plate and being adjustable to converge rearwardly towards the other.

8. A pasture topping machine according to claim 7 wherein each said cheek plate is hinged near its forward end to an inner surface of a respective said side plate, and secured near its rear end by a fastener to the top plate, the fastener extending through a slot in the top plate, thereby providing adjustment means for adjustment of conveyer of the side plates with respect to each other.

9. A method of topping pasture comprising moving a machine C' which is in accordance with any one of the preceding claims 00 '0 forwardly over pasture, severing the pasture with a scything 0 0 0!t action by driving said scythe blades rotationally while ~moving the machine forwardly creating a low air pressure zone :0 rearwardly of the machine, and blowing severed pasture 0 coo cuttings into said low pressure zone by air draft from said blades to effectively disperse the cuttings at the rear of the machine. 9 0 0

10. A pasture topping machine according to any one of the preceding claims with reference to and as illustrated in the 04(V accompanying drawings. a t

11. A method of topping pastures according to any one of the preceding claims with reference to and as illustrated in the accompanying drawings. Dated this 6th day of March 1991. CHRIS GROW ENGINEERING PTY LTD By its Patent Attorneys~ R K MADDERN ASSOCIATES