GB2169818A - Crushers - Google Patents

Abstract

The invention relates to crushers, particularly of the rotating hammer type, in which blocking of the crusher by conglomerated dirt and fines is obviated by a construction comprising hammers 6 rotatably mounted within a casing 4, at least one hammer having an outer transverse edge 14 adapted to wipe the inside face of the circular periphery of the casing, and side edges 15 adapted to wipe the inner faces of the side plates of the casing. <IMAGE>

Description

SPECIFICATION Crushers This invention relates to crushers. and is particularly concerned with crushers of the rotating-hammer type.

In many applications for which rotating-hammer type crushers are suited, the material fed to the crushers has a relatively high water content. This inevitably has the result of conglomerating dirt entrained with the material to be crushed and fines generated during the crushing action. Such conglomerated material tends to remain within the crusher, frequently blocking it and causing an unacceptably high down-time to allow cleaning to take place.

The object of the invention is to provide a rotating-hammer type crusher able to accept wet material with the substantial elimination of any blocking of the crusher by conglomerated dirt or fines.

According to the present invention a rotating-hammer type crusher comprises hammers rotatably mounted within a casing, at least one hammer having an outer transverse edge adapted to wipe the inside face of the circular periphery of the casing and side edges adapted to wipe the inner faces of the side plates of the casing.

In a preferred form, the means of feeding material comprises a ribbon-type screw located within a tube, to feed material to the eye of the rotating hammer assembly. In this form of construction, it is preferred to provide an inner transverse edge on at least one hammer adapted to wipe the outer face of the tube during rotation of the hammers.

Whilst one such hammer may be formed as defined above, it is preferable to form each hammer of the hammer assembly in this way.

By continuously wiping the inside faces of the casing and the outside face of the feed tube, any conglomerated dirt and fines is prevented from building-up to an extent sufficient to block the crusher, but is returned to the crushed material and fed out of the hammer along with the crushed material.

One embodiment of the invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a schematic, sectional side elevation of a rotating-hammer type crusher according to the invention; and Fig. 2 is a sectional end elevation on the line 2-2 of Fig. 1.

In the drawings, a ribbon flight conveyor 1 is held in position by two bearings 2 and driven by a motorised gearbox unit 3. The ribbon flight conveyor 1 is housed in a tubular casing 4 which incorporates an inlet 5 through which the feed material is to be fed. The ribbon flight conveyor housing is positioned centrally inside the rotary fixed hammer assembly 6, the central shaft 7 of which is mounted on taper roller bearings 8 in a steel casing 9.

The casing also incorporates the liner plates 10 and grid plates 11 and the crushed material outlet chute 12. The rotating hammer assembly 6 is driven from its central shaft 7 by any conventional type of drive e.g. vee ropes or directly through a gearbox.

Working operation of the crusher/screw assembly is basically as follows. Material is fed to the ribbon flight conveyor 1 through the inlet 5 in the ribbon flight conveyor housing 4.

The ribbon flight conveyor is reversible. When engaged in the forward direction the material is fed into the hammer assembly 6. On entering, the material comes into contact with the rotating hammers 6. Crushing action is assisted by liner plates 10 and grid plates 11 which control the size of the crushed material.

After crushing the crushed material falls through the grid plates 11 and is discharged via the outlet chute 12.

By-passing of the crusher can be achieved by reversing the ribbon flight conveyor 1, the feed material then being conveyed to the discharge opening 13 at that opposite end of the unit.

Each hammer 6 has an outer transverse edge 14 lying in close spaced relationship with the inside face of circular periphery of the casing, and side edges 15 in equally close spaced relationship with the side plates of the casing, more particularly the liner plates 10.

Additionally, each hammer has an inner transverse edge 16 lying in close proximity to the outside face of the feed tube 4. Thus, as the hammers are rotated the inside faces of the casing and the outside face of the feed tube are continuously wiped to prevent any build-up of conglomerated dirt and fines.

1. A rotating-hammer type crusher comprising hammers rotatably mounted within a casing, at least one hammer having an outer transverse edge adapted to wipe the inside face of the circular periphery of the casing, and side edges adapted to wipe the inner faces of the side plates of the casing.

2. A rotating-hammer crusher as in Claim 1, wherein the means of feeding material comprises a ribbon-type screw located within a tube, to feed material to the eye of the rotating hammer assembly, there being provided an inner transverse edge on at least one hammer adapted to wipe the outer face of the tube during rotation of the hammers.

3. A rotating-hammer type crusher substantially as hereinbefore described with reference to the accompanying drawings.

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

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Crushers This invention relates to crushers. and is particularly concerned with crushers of the rotating-hammer type. In many applications for which rotating-hammer type crushers are suited, the material fed to the crushers has a relatively high water content. This inevitably has the result of conglomerating dirt entrained with the material to be crushed and fines generated during the crushing action. Such conglomerated material tends to remain within the crusher, frequently blocking it and causing an unacceptably high down-time to allow cleaning to take place. The object of the invention is to provide a rotating-hammer type crusher able to accept wet material with the substantial elimination of any blocking of the crusher by conglomerated dirt or fines. According to the present invention a rotating-hammer type crusher comprises hammers rotatably mounted within a casing, at least one hammer having an outer transverse edge adapted to wipe the inside face of the circular periphery of the casing and side edges adapted to wipe the inner faces of the side plates of the casing. In a preferred form, the means of feeding material comprises a ribbon-type screw located within a tube, to feed material to the eye of the rotating hammer assembly. In this form of construction, it is preferred to provide an inner transverse edge on at least one hammer adapted to wipe the outer face of the tube during rotation of the hammers. Whilst one such hammer may be formed as defined above, it is preferable to form each hammer of the hammer assembly in this way. By continuously wiping the inside faces of the casing and the outside face of the feed tube, any conglomerated dirt and fines is prevented from building-up to an extent sufficient to block the crusher, but is returned to the crushed material and fed out of the hammer along with the crushed material. One embodiment of the invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a schematic, sectional side elevation of a rotating-hammer type crusher according to the invention; and Fig. 2 is a sectional end elevation on the line 2-2 of Fig. 1. In the drawings, a ribbon flight conveyor 1 is held in position by two bearings 2 and driven by a motorised gearbox unit 3. The ribbon flight conveyor 1 is housed in a tubular casing 4 which incorporates an inlet 5 through which the feed material is to be fed. The ribbon flight conveyor housing is positioned centrally inside the rotary fixed hammer assembly 6, the central shaft 7 of which is mounted on taper roller bearings 8 in a steel casing 9. The casing also incorporates the liner plates 10 and grid plates 11 and the crushed material outlet chute 12. The rotating hammer assembly 6 is driven from its central shaft 7 by any conventional type of drive e.g. vee ropes or directly through a gearbox. Working operation of the crusher/screw assembly is basically as follows. Material is fed to the ribbon flight conveyor 1 through the inlet 5 in the ribbon flight conveyor housing 4. The ribbon flight conveyor is reversible. When engaged in the forward direction the material is fed into the hammer assembly 6. On entering, the material comes into contact with the rotating hammers 6. Crushing action is assisted by liner plates 10 and grid plates 11 which control the size of the crushed material. After crushing the crushed material falls through the grid plates 11 and is discharged via the outlet chute 12. By-passing of the crusher can be achieved by reversing the ribbon flight conveyor 1, the feed material then being conveyed to the discharge opening 13 at that opposite end of the unit. Each hammer 6 has an outer transverse edge 14 lying in close spaced relationship with the inside face of circular periphery of the casing, and side edges 15 in equally close spaced relationship with the side plates of the casing, more particularly the liner plates 10. Additionally, each hammer has an inner transverse edge 16 lying in close proximity to the outside face of the feed tube 4. Thus, as the hammers are rotated the inside faces of the casing and the outside face of the feed tube are continuously wiped to prevent any build-up of conglomerated dirt and fines. CLAIMS

1. A rotating-hammer type crusher comprising hammers rotatably mounted within a casing, at least one hammer having an outer transverse edge adapted to wipe the inside face of the circular periphery of the casing, and side edges adapted to wipe the inner faces of the side plates of the casing.

2. A rotating-hammer crusher as in Claim 1, wherein the means of feeding material comprises a ribbon-type screw located within a tube, to feed material to the eye of the rotating hammer assembly, there being provided an inner transverse edge on at least one hammer adapted to wipe the outer face of the tube during rotation of the hammers.

3. A rotating-hammer type crusher substantially as hereinbefore described with reference to the accompanying drawings.