GB2230475A - Mineral crusher with access door - Google Patents

Abstract

A crusher (7) comprises a framework (3) having an interior (9) constituting a crusher chamber, and at least one access door (10) which carries at least a portion of the crusher screens or plates and is attached to the framework (3) by two pairs of link arms (16, 17) with one pair at each side of the door, the link arms (16, 17) of each pair being mutually spaced apart and each link arm (16, 17) being pivotted at one end to the door (10) and at the other end to the framework, with a force producing means e.g. turnbuckle (18) extending between the framework (3) and either the adjacent door side or the adjacent link (16) of a pair, whereby activation of turnbuckle (18) in a first direction displaces the associated door (10) from a closed position to an open position, and activation of the force producing means (18) in a second, opposite direction displaces the associated door (10) to a closed position, with the link geometry being such that the door is displaceable generally horizontally. <IMAGE>

Description

MINERAL ETC. CRUSHER This invention relates to a crusher or hammermill (hereinafter referred to as a Crusher) for the crushing/reduction/sizing etc. of minerals or other materials requiring f ragmentization.

A conventional crusher comprises a framework defining a crushing chamber within which chamber is a rotor and a Co- operating crusher screen(s) or plate(s), which together define an infeed nip or throat for the infeed of mineral to be crushed, with such mineral usually fed from overhead conveyors and chutework. Clearly, the crusher requires periodic internal inspection, maintenance and/or replacement of wear parts, and for this purpose at least one access door is conventionally provided.

According to the present invention, there is provided a crusher comprising a framework having an interior constituting a crushing chamber, and at least one access door attached to the framework by two pairs of link arms with one pair at each side of the door, the link arms of each pair being mutually spaced apart and each link arm being pivotted at one end to the door and at the other end to the framework, with a force producing means located at each side of the door and extending between the framework and either the adjacent door side or the adjacent link of a pair, whereby activation of the force producing means in a first direction displaces the associated door from a closed position to an open position, and activation of the force producing means in a second, opposite direction displaces the associated door to a closed position, with the link geometry being such that the door is displaceable generally horizontally.

The generally horizontal door opening and closing displacement enables associated feed conveyors and chuting to be installed in optimum feed locations, as there is no longer a need to cater for any, or any significant, vertical door movement.

According to another aspect of the invention of independent significance, the access door(s) carries the crusher screen(s) or plate(s), or a portion(s) of such screen(s) or plate, such that upon opening of the door(s) the screen(s) or plate(s) or portion(s) thereof is simultaneously withdrawn from the crushing chamber, for inspection, maintenance, replacement etc., and upon closing of the door(s) is simultaneously relocated within the crushing chamber.

This last mentioned aspect provides for easier inspection/manhandling/craning of the screen(s) or plate (s) or portion(s) thereof.

The crusher is conveniently provided with two access doors located at opposite sides of the crusher. In detail, each access door may be in the form of a fabricated door assembly, constituted by modular designed sideframes and endframes bolted together to form the access door(s). Each side of each door is preferably provided with a bracket whereby one end of each link arm may be pivotted to the side of each door via a pivot pin and the bracket, and the other end of each link arm may be fastened to a lower portion of the framework, again via a pivot pin and a bracket. The link arms of each pair of links are set at a predetermined distance apart to provide lemniscate geometry and operate in tandem in parallel motion. Conveniently, the force producing means is pivotally attached to the inner link arm of each pair, i.e.

the link arm that is nearer to the crushing chamber. The force producing means may take the form of a manually operable, or motorized, turnbuckle, or an hydraulic piston and cylinder unit. Preferably, the conventionallyprovided screen support members in the lower half of the crusher chamber are connected to the access door(s) by means of a quadrant shaped structure which supports the conventionally provided crusher screens in the lower section of the crusher chamber.There can be any number of such quadrant shaped support members dependent upon the width of the crusher, but there are always a minimum of two, i.e. one on each side, to provide the advantage referred to above in that when the door(s) is displaced to its open position, the screen assembly is simultaneously and automatically withdrawn from the crusher chamber to a location clear of the crusher chamber for easy inspection, maintenance and screen changes.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawing, in which: Figure l is a side view of a crusher in accordance with the invention; and Figure 2 is a view of another portion of Figure 1.

A crusher 7 comprises a rigid, fabricated framework 3 having an interior 9 constituting a crusher chamber, within which is the operative part of a rotor 4 rotatable about an axis 5, the rotor, in use, cooperating with a generally semicircular, concave crusher screen to crush/reduce/size mineral fed into the crusher 7 by a chute and conveyor system (not shown). The screen is defined by two replaceable screen halves 6, each being concave over approximately 9o, and each carried on a correspondingly concave support member 8.

Opposite ends of the rotor 4 are supported in bearings in spaced apart parallel walls 1, each of which is provided internally with an array of replaceable liner plates 2 described in greater detail in our copending GB Patent Application No. 8908883 (Agent's Ref. F289) filed simultaneously with the present Application. The walls 1 define opposite sides of the crusher 7 and fitting between the walls 1 are front and rear walls 18, each comprising an upper side frame 11, a lower side frame 12 and an end frame 19 bolted together. Each side of each door 18 is provided with a bracket 13, while a baseplate 14 of the framework 3 is provided with a bracket 15.By means of a pair of link arms, being an inner link arm 16 adjacent the crusher 7 and an outer link arm 17, each door 18 is pivotally attached to the framework 3. The link arm 16, 17, of each pair are parallel and spaced apart, and are pivotally attached at their upper ends to the bracket 13 and at their lower ends to the bracket 15. A force producing device in the form of a turnbuckle 18 is pivotally attached between the framework 3 and the inner link arm.

At the lefthand side of the Figure, the door 18 is shown in its closed position, while at the righthand side of the Figure the turnbuckle 1B has been activated to displace the door 1I11, virtually horizontally as a result of the geometry of the link arms 16, 17, to the open position. This not only provides access for inspection/maintenance of the crusher chamber, but it will be observed that one screen support member 8, and consequently one screen half 6, is carried by each door 1PI, so that the crusher in accordance with these aspects of the invention provides not only an advantageous, generally horizontal door opening/closing/or path, basically to provide maintenance etc. to the crusher interior, but also automatic withdrawl of the screen halves 6 from the crusher interior for easier inspection/manhandling/craning in their retracted, exposed position. It follows that reversal of this procedure closes up the crusher for reuse.

Claims (12)

1. A crusher comprising a framework having an interior constituting a crushing chamber, and at least one access door attached to the framework by two pairs of link arms with one pair at each side of the door, the link arms of each pair being mutually spaced apart and each link arm being pivotted at one end to the door and at the other end to the framework, with force producing means located at each side of the door and extending between the framework and either the adjacent door side or the adjacent link of a pair, whereby activation of the force producing means in a first direction displaces the associated door from a closed position to an open position, and activation of the force producing means in a second, opposite direction displaces the associated door to a closed position, with the link geometry being such that the door is displaceable generally horizontally.

2. A crusher comprising a framework having an interior constituting a crushing chamber, and at least one access door attached to the framework, wherein the access door(s) carries the crusher screen(s) or plate(s), or a portion (s) of such screen(s) or plate, such that upon opening of the door(s) the screen(s) or plate(s) or portion(s) thereof is simultaneously withdrawn from the crushing chamber, for inspection, maintenance, replacement etc., and upon closing of the door(s) is simultaneously relocated within the crushing chamber.

3. A crusher as claimed in Claim 1 or Claim 2, provided with two access doors located at opposite sides of the crusher.

4. A crusher as claimed in any preceding Claim, wherein the or each access door is in the form of a fabricated door assembly, constituted by modular designed sideframes and endframes bolted together to form the access door(s).

5. A crusher as claimed in Claim 4 when appendent to Claim 15 wherein each side of each door is provided with a bracket whereby one end of each link arm is pivoted to the side of each door via a pivot pin and the bracket, and the other end of each link arm is fastened to a lower portion of the framework, again via a pivot pin and a bracket.

6. A crusher as claimed in Claim 5, wherein the link arms of each pair of links are set at a predetermined distance apart to provide lemniscate geometry and operate in tandem in parallel motion.

7. A crusher as claimed in Claim 1, and any claim appendant thereto, wherein the force producing means is pivotally attached to the inner link arm of each pair.

8. A crusher as claimed in Claim 1, and any claim appendant thereto, wherein the force producing means takes the form of a manually operable, or motorized, turnbuckle, or an hydraulic piston and cylinder unit.

9. A crusher as claimed in Claim 1, and any claim appendant thereto, wherein the conventionally provided screen support members in the lower half of the crusher chamber are connected to the access doors by means of a quadrant shaped structure which supports the conventionally provided crusher screens in the lower section of the crusher chamber.

10. A crusher as claimed in Claim 9, wherein at least two quadrant shaped support members, one on each side are provided.

11. A crusher as claimed in Claim 1 and substantially as hereinbefore described with reference to the accompanying drawings.

12. A crusher as claimed in Claim 2, and substantially as hereinbefore described with reference to the accompanying drawings.