CA1153347A

CA1153347A - Mineral breakers

Info

Publication number: CA1153347A
Application number: CA000365533A
Authority: CA
Inventors: Alan Potts
Original assignee: MMD Design and Consultancy Ltd
Current assignee: MMD Design and Consultancy Ltd
Priority date: 1980-11-26
Filing date: 1980-11-26
Publication date: 1983-09-06

Abstract

ALAN POTTS

ABSTRACT
MINERAL BREAKERS
A mineral breaker having a pair of side by side breaker drums which are spaced laterally from one another and arranged to rotate in opposite directions, each drum having a plurality of breaker teeth arranged in circum-ferentially extending groups of teeth spaced along each drum with the groups of teeth on one drum being positioned so as to extend between the groups of teeth on the other drum.

Description

~15~.~3~';' MI~ERAL BREAKERS
Tne present invention relates to miner31 break~r~
in particularlv, to miner~l breakers for use in coal mi~in;
for ensuring maximum sizing of coal, According to the present invention there is provided a mineral breaker having a pair of side by side brea'~er drums which are spaced laterally from one another and arranged to rotate in opposite directions, each drum having a plurality of breaker teeth arranged in circumferentially extending groups of teeth spaced along each drum with the i groups of teeth on one drum being positioned so as to extend between the groups of teeth on the other drum.
Reference is now made to the accompanying drawings, I
in which: !
Figure 1 is a plan view, partly in section, of a mineral breaker according to the present invention;
Figure 2 is a side view of th'e mineral breaker shown in Figure l;
Figure 3 is a sectional view taken along line III~
20 in Figure 2;
Figure 4 is a similar view to that of Figure 3 of a different embodiment according to the present invention;
Referring initially to Figures 1 to 3, a mineral breaker 10 includes a main frame 11, which in use is 25 capable of being sited over a conveyor for depositing t sized material onto the conveyor which then transports the sized mineral away. The frame 11 houses a pair of breaker drums 14 which are located within a chamber lla defined by side walls llb of the housing and end support walls 50,51. Each of the drums 14 is fixedly mounted on shafts 15 and 16 respectively. Each drum is provided with a plurality of breaker teeth 17 which are arranged in cir-cumferentially extending groups of teeth, with the groups on one drum being positioned so as to extend between the groups on the other drum.
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Both shafts 15,16 are ro-tatably supported at each end in bearing assemblies 19,20 respectively. Each pair of bearing assemblies 19,20 are respec-tively moun-ted wi-thin bearing seats 52,53 formed in end suppor-t walls 50,51 respectively. The end support walls 50,51 are each composed of two separate halves 50a, 50_ and 51_,51_ respectively, ` each half being secured to the side walls of the housing by bolts 54. Thus by separating adjoined halves it is possible to remove the respective bearing assemblies from the end support walls.
Shaft 15 is drivingly connected via a drive coupling 28 to an electric motor and reduction gear box assembly 30 which is bolted to an end plate 58 of the housing 11. Prefer-ably the drive coupling 28 is of similar cons-truction to that disclosed in U.K. Patent application 40511/78 published on May 21, 1980 under Publication No. 2033538.
Shafts 15 and 16 are drivingly connected to one another by means of a pair of meshing gears 35 so that the drums 14 , rotate in opposite directions. -As shown in ~igure 3 the angular position of the teeth on one drum in relation to those on the ;- other drum is preferably arranged so that teeth on one drum extend between the circumferential spacing between teeth on the other drum. This relative angular posi-tion is maintained during operation by the meshing gears 35. It will be appreciated that the relative angular position between teeth on the drums may be adjusted as desired by changing the relative angular position of meshing gears 35. By changing the relative angular positions of the teeth on the drums 14 it is possible to adjust the breaker so as to produce sized material of a predetermined ` 30 size.

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3~'7 The breaker teeth 17 are of a robus-t construc-tion, as seen in Figures 3 and 4, and are cons-tructed so a~ to be~
capable of breaking minera] which -the breaker is in-l:ended -I:o , size. According, due to the interrelationship of -the : breaker teeth 17 all oversized mineral passin~ be-tween -the 2a -, ,~,'"
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- , 1~53347 breaker drums 14 is brqken to ~rovide sized mineral w~i_h is of a predetermined maximum size.
The shape of the breaker teeth 17 facilitates breaking of the oversized mineral in that a recess 59 ls provi~ed between adjacent rear faces 60 of teeth 17, the rear face of each tooth 17 being defined by a ridqe 61 which in cross-section is arcuate as shown in Figures ~ and 4.
The width of rid~e 61 is chosen bearing in mind the working conditions of the breaker. Accordingly oversized material ~
10 will initially be seated across the ridges 61 of one or '?"
more adjacent teeth 17 on one drum and then on rotation of the drums, the front face 62 of teeth 17 on the other drum will engage the oversized material seated on the ridges 61. The oversized mineral will therefore be subjected to opposed loadings along its length thus causing it to fracture.
As seen in Figures 3 and 4, the front face 62 of , .
each tooth 17 is inclined so as to define with an acute enclosed angled~ with the tangent to the circumference ~ of the drum at the point of intersection of the face 62 ; 20 with the periphery of the drum. It will be appreciated that angle oL may be varied as desired to suit working - conditions of the mineral breaker.
In the embodiment of Figures 1 to 3, the teeth 17 on each drum 14 are formed separately to the drum 14.
Thus sets of teeth 17 are cast together to form an elong-ate toothed strip 17a which includes a body portion 17b and teeth 17 projecting therefrom. The body portion 17b is provided with a rib 17c which extends longitudinally along same side of the body portion 17b as that from which the front faces 62 of teeth 17 are located.
, Each drum 14 is provided with longitudinally extending channels 70 spaced circumferentially from one another. Each channel 70 has a bottom wall 70a against which the bottom face 17d of the body portion 17b abuts in use. Each channel also has a groove 71 for housing rib 17c as seen in Figure 3. Each drum 14 is provided ' ~ ,. 1 .
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with bolt stud~ 75 which are anchore~ i~ the dr~ and project outwards into channel 7a. The strips 17a are provided with apertures 80 and nut accomodating recess~s 81 for securing each strip to the drum. For the sake o~
simplici~ty, apertures 80 and recesses 81 have ~een omitted from Figure 2, t~eir locati~on being ~dentified by crosses A. As seen ~n Figure 2 ! two str~ps 17a are provided ~n eac~ channel 70. It ~ e appreciated that toothed drums of vary~ng lengths may easily be constructed using one or more strips 17a per channel 70.
The method of securing the strip 17a to the drums 14 described above is particularly advantageous since removal l;
of the strips is relatively simple ~y removal of nuts 76 whilst, in use, loadingsapplied to the front faces S2 of p t~e teeth are transmitted to the drum via ribs 17c and co-operating grooves 71 and the bottom face 17d of the body portion 17b and the bottom wald 70a of channel 70.
Thus in use, bolt studs 75 and nuts 76 are not loaded by the breaking operation of the drums.
It is to be noted that in Figure 3 all teeth 17 are formed on strips 17_ and that for the sake of simplicity only one strip 17a is shown.
In the embodiment of Figure 4, all parts of the breaker are the same as those described in respect of the embodiment of Figures 1 to 3 apart from the drum construc-tion. Thus, in Figure 4, teeth 17 are formed integrally ; with drums 14 instead of being formed on strips 17a.
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Claims

I CLAIM:

1. A mineral breaker having a pair of side by side breaker drums which are spaced laterally from one another and arranged to rotate in opposite directions, each drum having a plurality of breaker teeth arranged in circumferen-tially extending groups of teeth spaced along each drum with the groups of teeth on one drum being positioned so as to extend between the groups of teeth on the other drum, the angular position of teeth on one drum in relation to those on the other drum is arranged so that teeth on one drum extend between the circumferential spacing between the groups on the other drum, the teeth on one drum cooperating with teeth on the other drum to place oversized mineral under tensile loadings to effect breakage of the oversized mineral.

2. A mineral breaker according to claim 1, wherein each tooth on each drum is provided with a ridge projecting rearwardly, in the direction of rotation.

3. A mineral breaker according to claim 2, wherein the ridge of each tooth is arcuate in cross-section.

4. A mineral breaker according to claim 1, 2 or 3, wherein the leading face of each tooth on each drum is sub-stantially planar.

5. A mineral breaker according to claim 1, 2 or 3, wherein the teeth on each drum are integrally formed therewith.

6. A mineral breaker according to claim 1, wherein the teeth on each drum are releasably connected to the drum.

7. A mineral breaker according to claim 6, wherein the teeth are formed as part of elongate toothed strips, the strips being releasably connected to a respective drum so as to extend along the length of the drum.

8. A mineral breaker according to claim 7, wherein each strip has a body portion from which said teeth project and a rib projecting from the leading side of the body portion, the drum having longitudinally extending channels for receiving the body portion and a recess formed in the lead-ing side wall of each channel for accommodating said rib.