AU717575B2 - Concrete pulveriser - Google Patents

Description

Cd 1

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor: Address for Service: Invention Title: EPHEMERE PTY LTD 010 693 231) Norman John Smith CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

CONCRETE PULVERISER a a a a.

Details of Associated Provisional Applications: Nos. P00790 a The following statement is a full description of this invention, including the best method of performing it known to us 2 BACKGROUND OF THE INVENTION This invention relates to equipment for pulverising concrete, rock and other similar large aggregate material. The invention is particularly concerned with improvements in an excavator mounted tool which is commonly used for this purpose.

Excavator mounted pulverising tools of the type with which the invention is concerned, typically comprise hinged jaws having a multiplicity of conically shaped teeth projecting inwardly from the face of one jaw and a corresponding number of aligned openings for the teeth to mesh with in the face of the opposing jaw. Material to be pulverised is gripped between the jaws and crushed by the huge forces exerted by the jaws. Any steel reinforcement which may be present in the material, such as in reinforced concrete, is simultaneously cut by cutting blades adjacent the hinge end of the jaws.

Such pulverising tools are subject to a huge amount of wear and tear, and it is necessary to replace, 20 individually, the teeth of the one jaw at frequent o intervals and to weld plates onto the other jaw to patch the damage. Teeth can be replaced by the straightforward process of unbolting a threaded stem of the tooth which extends to the opposite side of the jaw, extracting 25 the tooth, and inserting a replacement. However the wear and tear which occurs to the opposing jaw having a gridwork of apertures cannot be so easily dealt with. It is necessary to cut and patch an array of different sized plates over the damaged regions. This is an extremely V 30 time consuming and unsatisfactory process which, moreover, does not provide a very long lasting or satisfactory result.

OBJECT OF THE INVENTION It is therefore an object of this invention to provide a quick and convenient method of fixing the apertured jaw of the hinged jaws of a pulverising tool which has become damaged during use.

SUMMARY OF THE INVENTION

AF

3 Accordingly, the present invention provides a pulverising tool having hinged jaws, one of said jaws including a multiplicity of pointed teeth extending from one face thereof, the other of said jaws including a corresponding number of apertures which align with the teeth when the jaws are brought together, said pulverising tool characterised by a plurality of shrouds which wrap around the sides which define the apertures in the one said jaw, said shrouds being attached to said sides by pins which can be removed when it is required to replace an individual shroud.

The provision of shrouds enables a quick and convenient method for replacing worn or damaged regions of the apertured jaw as it is only necessary to extract a holding pin and the worn or damaged shroud or shrouds can then be removed and replaced with a new shroud or shrouds.

DETAILED DESCRIPTION OF THE INVENTION The shrouds can be standardised in design so that only a minimal number of different designs of shroud are required. Preferably, the shroud will have a substantially U-shaped profile with the facing edge S"including a ridge which is honed at an angle of about 600 in order to increase the fracture forces on the material being pulverised. Aligned openings are formed in the wings of the shroud to enable a pin to be inserted therethrough into a corresponding hole in the jaw framework to retain the shroud in situ and to permit ready decoupling from the framework when replacement is 30 required.

Typically, there are five different shroud designs which fit together to make a rectangular grid covering the facing support wall components of the jaw.

The number of designs of the individual shrouds will, nevertheless, be determined by the particular pattern of openings and the overall configuration of the jaw.

The shrouds are preferably manufactured from wear resistant caste steel having a Brinell Hardness lying within the range of 300-550.

The invention also extends to the individual shrouds themselves.

Accordingly in this second aspect of the present invention there is provided a shroud which wraps around an inwardly facing edge of an apertured jaw of a pulverising tool having hinged jaws, said shroud comprising two parallel plates interconnected by a wear resisting tip, which plates and tip together have a substantially U-shaped profile.

DESCRIPTION OF THE DRAWINGS Figure 1 is a partial perspective of a grid of shrouds supported by a pulveriser according to one aspect of the present invention, Figure 2 is a front perspective view of a individual shroud shown in Figure 1, Figure 3 is a rear perspective view of the shroud shown in Figure 2, and 20 Figure 4 is a front perspective view of a pulverising tool in which the grid of Figure 1 is arranged.

S"DESCRIPTION OF PREFERRED EMBODIMENTS Preferred embodiments of the invention will now 25 be described with reference to the drawings.

In all of the drawings, like reference numerals refer to like parts.

Referring firstly to Figure 1, there are illustrated, in part, five differently configured shrouds 10, 11, 12, 13, 14 supported in a rectangular grid formation on an open jaw of a pulverising tool (see Figure 4 for a full view of the tool) Each shroud is connected to a rigid support framework of the jaw by means of a hardened steel pin (not shown) which extends through an associated opening, for instance see referenced items 15, 16, 17, 18, 19, formed in each wing of the shroud. The pin itself may be retained by a spring circlip or the like, or may be screw-threaded into the shroud.

The shrouds are designed so that they can be individually removed, by extracting the pin, as they become worn or damaged, and replaced by a similar configured shroud.

A typical shroud 11 is illustrated in Figures 2 and 3 to which reference is now made. This shroud comprises two substantially parallel plates 20, 21 separated by a tip hardened and strengthened connecting piece 22 having an outwardly facing ridge 23 which is honed at an angle of approximately 450. The top and bottom edges 24, 25 of the shroud are flared to give greater strength to the shroud which is fabricated from wear resisting caste steel having a Brinell Hardness of approximately 500.

Aligned openings 26, 27 extend through the side plates of the shroud to enable a fixing pin to be inserted therethrough so as to connect with the supporting framework of the pulverising tool.

Figure 4 shows how the shrouds are arranged on the pulveriser tool which consists of two hinged jaws oo.* 31. Jaw 31 contains a plurality of conically shaped pointed teeth 32 arrayed in such a manner as to be aligned with corresponding openings 33 in jaw 30. The 25 openings in jaw 30 are defined by a framework in which the shroud elements 10, 11, 12, 13, 14 are arranged as previously described.

The provision of shrouds according to the oo present invention enables any damaged or worn shrouds on the pulverising tool to be quickly and effectively replaced with minimal downtime for the equipment, thence leading to increased productivity and minimal cost outlays.

Whilst the above has been given by way of illustrative example of the invention, many modifications and variation may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth.

Claims (5)

1. A pulverising tool having hinged jaws, one of said jaws including a multiplicity of pointed teeth projecting inwardly from one face thereof, the other of said jaws including a number of corresponding apertures which align with the teeth when the jaws are brought together, said pulverising tool characterised by a plurality of shroud elements which wrap around the sides which define the apertures in the one jaw, said shrouds being attached to said sides by removable pins.

2. A pulverising tool as claimed in claim i, wherein at least some of the shroud elements have a substantially U-shaped profile.

3. A pulverising tool as claimed in claim 2, wherein each shroud element has aligned openings in its wings for accommodating a removable pin which connects the shroud element to the jaw.

4. A pulverising tool as claimed in claim 2 or claim 3, wherein the facing edge of each U-shaped shroud 20 element comprises a ridge which is honed at an angle of o o

30-60 5. A pulverising tool as claimed in any one of the S"preceding claims, wherein the shroud is manufactured from wear resistant caste steel having a Brinell Hardness of 25 300-550. 6. A shroud which is adapted to wrap around a facing edge of an apertured jaw of a pulverising tool having a pair of hinged jaws, said shroud comprising two parallel plate sections separated by a wear resisting tip, which plate sections and tip together form a S"substantially U-shaped profile. 7. A shroud as claimed in claim 6 which includes an aligned opening in each of its plate sections for housing a connecting pin. 8. A shroud as claimed in claim 6 or claim 7, wherein the wear resisting tip is wedge-shaped and is honed at an angle of 30-600. 9. A shroud as claimed in any one of claims 6-8, which is manufactured from wear resistant caste-steel having a Brinell Hardness of 300-550. A pulverising tool substantially as herein described with reference to Figure 4 of the accompanying drawings. 11. A shroud substantially as herein described with reference to Figures 2 and 3 of the accompanying drawings. DATED this 3rd day of July 1997 EPHEMERE PTY LTD 010 693 231) By their Patent Attorneys CULLEN CO.