WO1981001527A1

WO1981001527A1 - Electric shredder

Info

Publication number: WO1981001527A1
Application number: PCT/AU1980/000103
Authority: WO
Inventors: D Green
Original assignee: Royer Mowers Aust Pty Ltd
Current assignee: Royer Mowers Aust Pty Ltd
Priority date: 1979-12-04
Filing date: 1980-12-01
Publication date: 1981-06-11
Anticipated expiration: 1982-06-04
Also published as: GB2079625A; FR2471132A1; JPS56501673A

Abstract

A shredding machine having a shredding chamber (10) includes two substantially flat parallel spaced apart walls forming the top (24) and bottom (2) walls respectively of the chamber. A shredder blade (27) assembly is supported on a vertical axle (25) rotatably supported and passing through the bottom wall of the chamber (2). A feed hopper (41) is mounted on the top wall (24) of the chamber and offset from the centre of the chamber and communicates with the interior of the chamber through a feed opening in the top wall (24). The bottom wall (2) of the chamber is provided with a discharge opening (9) which is offset from the centre of the bottom wall and offset from the feed opening.

Description

ELECTRIC SHREDDER

This invention relates to an improved shredding machine and whilst not limited thereto, the invention is particularly applicable for shredding garden clippings and refuse. Garden clippings and refuse can become extremely bulky. It is difficult to dispose and if left in the uncomminuted state it takes lengthy periods to decompose to the stage where it can be used for garden fertilisation purposes. The object of the present invention is to provide a comparatively lightweight shredding machine which has the capacity to shred and comminute normal garden clippings and garden refuse associated with most domestic homes.

The invention in its broadest aspect comprises a shredding machine having a shredding chamber which includes at least two substantially flat parallel spaced apart walls forming the top and bottom walls respectively of said chamber, a shredder blade assembly inside said chamber and supported on a vertical axle passing through at least the bottom wall thereof and driven by a motor mounted below said chamber, a feed hopper mounted on the top wall of said chamber offset from the centre thereof and communicating with said chamber through an opening in the top, wall thereof and a discharge opening in the bottom wall of said chamber offset from the centre thereof .and offset to said feeder opening. A preferred embodiment of the invention will now be described with reference to the accompanying drawings in which

Fig. 1 is a part exploded perspective view of the shredding machine according to the invention; Fig. 2 is a side elevation of the shredding machine; Fig. 3 is a plan view of Fig. 2;

Fig. 4 is a sectional view on line iv-iv of Fig. 1; Fig. 5 is a plan view of Fig. 4, and

Fig. 6 is a view of the machine housing showing the motor and its drive arrangement.

The shredder includes a housing designated generally by the reference 1, conveniently formed of metal e.g. aluminimum in a moulding operation.

The housing has a flat wall 2 with side walls 3, 4, 5 and 6 depending therefrom and the side wall 5 is merged into the side wall 6 by curved portion 7. The bottom edges of the walls 4 and 6 are angled upwardly and then downwardly to define the wall 8 spaced from the wall 5. The wall 8, the wall 5 and the end portions of the walls 4 and 6 form a discharge duct designated generally by the reference 9 (see Fig. 1).

The wall 2 extends across the top of the housing and has an opening 10 therein which is complementary in shape to and communicates with the discharge duct 9. Upstanding from wall 2 is a side wall member designated generally by the reference 11 having a curved portion 12 and straight side wall portions 13 and 14. Portions 13 and 14 are formed by extensions of the walls 4 and 5.

The housing is supported for movement on wheels to facilitate movement of the machine to different locations. To this end a handle comprising a "U" shaped member designated generally by the reference 15 is secured to the wall 5 by brackets 15a. The two limbs 16 and 17 of this member extend downwardly from the housing and are then bent forwardly. The ends of the limbs 16 and 17 are connected to the legs 18 and 19 as illustrated in Fig. 2. Brackets 20 fixed to the limbs 16 and 17 support an axle 21 on which wheels 22 and 23 are rotatably mounted.

The side wall member 11, the wall 2 and the cover member 24 constitute the shredding chamber with the cover 24 constituting the top wall thereof and the wall 2 constituting the bottom wall thereof. That portion of the housing below the wall 2 between the discharge duct 9 and the wall 3 constitutes a motor compartment.

A blade assembly is rotatable in the shredding chamber. This assembly includes an axle 25 rotatably supported in bearing member 26 and extends through the wall 2. The axle has a cutting blade 27 fixed thereto by a nut and washer 28 and the opposite end of the axle 25 has a pulley wheel 29 fixed thereto below the wall 2 and in the embodiment being described is driven by a belt 30 from a pulley 31 fixed to the drive shaft of an electric motor 32 mounted in the machinery compartment. Where an electric motor is used to power the shredder it is necessary that the pulley 31 be of heavyweight material to assist the inertia of the blade 27.

It will be appreciated that if desired a low horsepower internal combustion engine could replace the electric motor 32.

As previously stated the shredding chamber is closed by a cover member 24. The walls 4 and 6 have lugs 33 and 34 fixed thereto in which are secured upstanding screwed rods 35 and 36. The rods pass through corresponding bores in lugs 37 and 38 fixed to the cover member 24 whereby the cover may be detachably secured in position with the aid of wing nuts 39 and 40.

The cover member 34 has an opening therein which in the closed position of the cover is located above the wall 2 and remote from the discharge duct 9. Fixed to the upper surface of the cover member 24 and communicating with the shredding chamber via this opening is a feed hopper designated generally by the reference 41. The cover member 24 also has a domed portion 42 to accommodate the end of the shaft 25 when the cover is in the closed position. The hopper 41 includes angled wall members 43, 44, 45 and 46 and straight wall members 47, 48, 49 and 50. The respective wall members may be secured together as by welding or alternatively the entire hopper may be formed in a molding operation.

The hopper 41 is provided with a feed mechanism designated generally by the reference 51 which allows controlled feeding of the material to be shredded to the shredding chamber and at the same time it closes the opening in the hopper to the extent that it prevents the user from accidently contacting the cutting blade 27 with his hands. Additionally the feed mechanism prevents material from being ejected upwardly through the hopper from the shredding chamber during the operation of the machine.

The feed mechanism 51 comprises two rollers 52 and 53 fixed to shafts 54 and 55 rotatably supported in the wall members 47 and 49. The shaft 54 is provided with a handle 56 whereby the rollers 52 and 53 may be manually rotated in the manner to be described.

The rollers 52 and 53 are of such length and diameter that may substantially completely close the hopper with working clearance. Both rollers are provided with ribbed or fluted surfaces as indicated in Fig. 4 and the shaft 55 is supported in slots 57. Springs 58, are secured by one end to each end of the shaft 55 and the free ends of these springs are secured to anchor points 59 of the wall members 47 and 49.

As will be apparent the rollers 52 and 53 are urged into contact with each other by the springs 58 and the distance the rollers can be forced apart by material being fed therebetween is governed by the length of the slots 57 and so determines the size or bulk of the material which can be fed between. the rollers to the shredding chamber. This arrangement constitutes an effective overload control and ensures that only material which the machine is designed to shred is fed to it.

The exterior walls of the discharge duct 9 are provided with hooks 60 only one of which is shown in Fig. 1 whereby a refuse container (not shown) such as a bag may if desired be attached below the discharge duct to collect material shredded by the machine. A handle 61 is fixed to the wall 3 to facilitate the manipulation of the machine.

In use the motor is actuated. This causes the blade 27 to rotate in the shredding chamber. Material to be shredded is fed by hand into the hopper and the handle 56 rotated manually. This causes the rollers 52 and 53 to rotate towards each other and in so doing the material in the hopper is fed to the shredding chamber where it is reduced to fine particles and falls by gravity through the duct 9.

It will be appreciated that in the emodiment described the rollers are rotated manually by the handle 56. It is however within the scope of this invention that the rollers could be rotated mechanically by an appropriate drive arrangement as is well understood in the art from the motor 32.

Claims

CLAIMS 1. A shredding machine having a shredding chamber which includes at least two substantially flat parallel spaced apart walls forming the top and bottom walls respectively of said chamber, a shredder blade assembly inside said chamber and supported on a vertical axle passing through at least the bottom wall and driven by a motor mounted below said chamber, a feed hopper .mounted on the top wall of said chamber offset from the centre thereof and communicating with said chamber through an opening in said top wall and a discharge opening in the bottom wall of said compartment offset from the centre thereof and offset to said feed opening.

2. A shredding machine as claimed in claim 1 wherein said discharge opening communicates with a duct forming a unitary structure with said shredding compartment and wherein side walls of said compartment extend downwardly past said bottom wall to form an enclosure for said motor.

3. A shredding machine as claimed in claim 2 wherein said duct has means thereon to removably connect a receptacle thereto.

4. A shredding machine as claimed in any one of claims 1 to 3 wherein the motor is an electric motor connected by a belt drive to said axle.

5. A shredding machine as claimed in any one of the preceding claims wherein said top wall with said feed hopper is detachable from said chamber.

6. A shredding machine as claimed in any one of the preceding claims wherein said hopper has a pair of horizontally interacting feed rollers rotatably supported therein.

7. A shredding machine as claimed in claim 6 wherein the axis of said feed rollers are urged by springs against each other and are separable against said springs by a predetermined amount.

8. A shredding machine as claimed in claim 7 wherein one of the rollers is rotatable by a crank handle.

9. A shredding machine as claimed in any one of the preceding. claims wherein the machine is supported on a leg assembly incorporating at least two wheels.

10. A shredding machine substantially as hereinbefore described with reference to the accompanying drawings.