GB2142675A

GB2142675A - Drum assembly

Info

Publication number: GB2142675A
Application number: GB08317045A
Authority: GB
Inventors: Alan Potts
Original assignee: MMD Design and Consultancy Ltd
Current assignee: MMD Design and Consultancy Ltd
Priority date: 1983-06-23
Filing date: 1983-06-23
Publication date: 1985-01-23
Also published as: GB8317045D0; GB2142675B

Abstract

A breaker drum assembly fore mineral breaker, the drum assembly including a drum 10 having a plurality of longitudinally extending slots 24 spaced about its periphery so as to define a plurality of circumferentially spaced longitudinally extending projections 26, and a series of shroud segments 12 received on each projection, the shroud segments and respective projections having co- operating formations to enable the shroud segments to be slidably received on a respective projection. <IMAGE>

Description

SPECIFICATION Drum assembly The present invention relates to a drum assembly for a mineral breaker, and also a mineral breaker including one or more such drum assemblies.

Various aspects of the present invention are hereinafter described with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional view through a drum assembly according to the present invention; Figure 2 is an axial section through the drum assembly shown in Figure 1 with all teeth segments removed; Figure 3 is an end view ofthe drum assembly as shown in Figure 2; Figure 4 is a plan view of an individual tooth segment.

The drum assembly according to the present invention basically comprises a drum 10 and shroud segments 1 2 which are removably attached to the periphery of the drum 10.

The drum 10 is conveniently a single casting from a suitable metal and has a pair of annular end portions 14, 1 5 containing aligned bores 16, 17 respectively which in use are keyed to a supporting shaft (not shown) for rotatably supporting the drum in a mineral breaker.

The interior of the drum 10 between annular end portions 14, 15 preferably defines a hollow portion 18 so as to reduce material and weight of the drum.

The outer periphery of the drum is provided with a series of longitudinally extending slots 24 which are equally spaced about the periphery of the drum. The slots 24, in cross-section are of a dovetail shape in order to define between adjacent slots longitudinally extending projections 26 having inwardly inclined side walls 27. The projections 26, therefore, may also be considered to be generally of a dovetail shape in crosssection. The shroud segment 1 2 are preferably cvase from a hard wearing, abrasive resistant metal such as a manganese steel and are shaped to have a shroud portion 28 and depending lugs 29, 30 having internal walls defining a recess which is complimentary to the cross-sectional shape of projections 26.

Accordingly, shroud segments 12 can be slid onto one end of a projection 26 and slid axially along the drum. In use, a plurality of shroud segments 12 are slid onto each projection 26 so that each projection is totally shrouded by the shroud segments received thereon. The lugs 29, 30 are provided with end faces 31,32 respectively which co-operate so as to provide a contiguous peripheral surface between abutting shroud segments located on adjacent projections 26.

Preferably at one end of the drum 10, the slots 24 are provided with stops 33 against which end shroud segments abut and thereby are prevented from sliding axially off that end of the drum. At the opposite end of the drum the shroud segments are preferably prevented from sliding off the drum by means of arcuate segments (not shown) removably attached to the end of each projection.

Each arcuate segment is preferably attached to its associated projection 26 by a pair of through bolts (not shown) each of which is screw threadedly received in a removable bobbin 35, the bolt communicating with the bobbin through a clearance bore 36.

Accordingly in the event of a bolt seizing it is possible to drill the bolt out and replace the bobbin 35 to give a new threaded bore to receive the new bolt.

Each shroud segment 1 2 is preferably provided with radially projecting breaker teeth 40 which are preferably cast integrally with the shroud portion 28.

In the drawing faces 31,32 are similar and radially extending of the drum. It is envisaged that they may be inclined to the radial direction so as to prevent a shroud segment being slid onto a projection with its teeth pointing in the wrong direction.

When the above drum assembly is mounted in a mineral breaker, an end wall of the housing of the mineral breaker is preferably provided with a closable window through which access may be had to the arcuate segments. On removal of an arcuate segment from an associated projection 26 the shroud segments 12 on that projection may then be removed from the drum for replacement following wear or breakage of the breaker teeth.

Apart from the advantage of providing a simple system of tooth replacement, the shroud segments provide a positive anchorage for the teeth in both directions of rotation of the drum as well as radially due to the interaction of the lugs 29, 30 and side walls 27 of projections 26.

Additionally it is possible with the design of shroud segment to reduce the wall thickness of the shroud portion 28 to a minimum thereby providing a significant saving in material.

It will be appreciated that the number of teeth 40 and shape thereof projectiung from each segment 12 may be varied as desired.

1. A breaker drum assembly for a mineral breaker, the dmm assembly including a drum having a plurality of longitudinally extending slots spaced about its periphery so as to define a plurality of circumferentially spaced longitudinally extending projections, and a series of shroud segments received on each projection, the shroud segments and respective projections having co-operating formations to enable the shroud segments to be slidably received on a respective projection.

2. A drum assembly according to Claim 1 wherein the side walls defining said slots are inclined so that, in cross-section, the projections are of dove-tail shape.

3. A drum assembly according to Claim 1 or 2 wherein the end walls of a series of shrouds abut against the end walls of shrouds of a neighbouring series of shrouds.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Drum assembly The present invention relates to a drum assembly for a mineral breaker, and also a mineral breaker including one or more such drum assemblies. Various aspects of the present invention are hereinafter described with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional view through a drum assembly according to the present invention; Figure 2 is an axial section through the drum assembly shown in Figure 1 with all teeth segments removed; Figure 3 is an end view ofthe drum assembly as shown in Figure 2; Figure 4 is a plan view of an individual tooth segment. The drum assembly according to the present invention basically comprises a drum 10 and shroud segments 1 2 which are removably attached to the periphery of the drum 10. The drum 10 is conveniently a single casting from a suitable metal and has a pair of annular end portions 14, 1 5 containing aligned bores 16, 17 respectively which in use are keyed to a supporting shaft (not shown) for rotatably supporting the drum in a mineral breaker. The interior of the drum 10 between annular end portions 14, 15 preferably defines a hollow portion 18 so as to reduce material and weight of the drum. The outer periphery of the drum is provided with a series of longitudinally extending slots 24 which are equally spaced about the periphery of the drum. The slots 24, in cross-section are of a dovetail shape in order to define between adjacent slots longitudinally extending projections 26 having inwardly inclined side walls 27. The projections 26, therefore, may also be considered to be generally of a dovetail shape in crosssection. The shroud segment 1 2 are preferably cvase from a hard wearing, abrasive resistant metal such as a manganese steel and are shaped to have a shroud portion 28 and depending lugs 29, 30 having internal walls defining a recess which is complimentary to the cross-sectional shape of projections 26. Accordingly, shroud segments 12 can be slid onto one end of a projection 26 and slid axially along the drum. In use, a plurality of shroud segments 12 are slid onto each projection 26 so that each projection is totally shrouded by the shroud segments received thereon. The lugs 29, 30 are provided with end faces 31,32 respectively which co-operate so as to provide a contiguous peripheral surface between abutting shroud segments located on adjacent projections 26. Preferably at one end of the drum 10, the slots 24 are provided with stops 33 against which end shroud segments abut and thereby are prevented from sliding axially off that end of the drum. At the opposite end of the drum the shroud segments are preferably prevented from sliding off the drum by means of arcuate segments (not shown) removably attached to the end of each projection. Each arcuate segment is preferably attached to its associated projection 26 by a pair of through bolts (not shown) each of which is screw threadedly received in a removable bobbin 35, the bolt communicating with the bobbin through a clearance bore 36. Accordingly in the event of a bolt seizing it is possible to drill the bolt out and replace the bobbin 35 to give a new threaded bore to receive the new bolt. Each shroud segment 1 2 is preferably provided with radially projecting breaker teeth 40 which are preferably cast integrally with the shroud portion 28. In the drawing faces 31,32 are similar and radially extending of the drum. It is envisaged that they may be inclined to the radial direction so as to prevent a shroud segment being slid onto a projection with its teeth pointing in the wrong direction. When the above drum assembly is mounted in a mineral breaker, an end wall of the housing of the mineral breaker is preferably provided with a closable window through which access may be had to the arcuate segments. On removal of an arcuate segment from an associated projection 26 the shroud segments 12 on that projection may then be removed from the drum for replacement following wear or breakage of the breaker teeth. Apart from the advantage of providing a simple system of tooth replacement, the shroud segments provide a positive anchorage for the teeth in both directions of rotation of the drum as well as radially due to the interaction of the lugs 29, 30 and side walls 27 of projections 26. Additionally it is possible with the design of shroud segment to reduce the wall thickness of the shroud portion 28 to a minimum thereby providing a significant saving in material. It will be appreciated that the number of teeth 40 and shape thereof projectiung from each segment 12 may be varied as desired. CLAIMS

4. A drum assembly according to Claim 1 2 or 3 wherein each series of segments is prevented from longitudinal movement by stops provided at one end of the slots and removable stops located at the opposite end of the drum, the removable stops being detachably secured to a respective projection.

5. A drum assembly according to any preceding claim wherein the drum is cast in one piece so as to have a pair of annular end portions containing aligned bores for receiving a shaft and a hollow central portion extending between the annular end portions.

6. A breaker drum assembly substantially as described with reference to and as illustrated in the accompanying drawings.

7. A mineral breaker including a breaker drum assembly according to any preceding claim.