GB1588403A

GB1588403A - Machine for crushing bulk material

Info

Publication number: GB1588403A
Application number: GB16296/78A
Authority: GB
Original assignee: BOHMTER MASCHF
Current assignee: BOHMTER MASCHF
Priority date: 1977-05-06
Filing date: 1978-04-25
Publication date: 1981-04-23
Also published as: DD136707A5; DE7714343U1; SE7804672L; CA1104107A; CH628529A5; FR2389412B1; ATA284278A; FR2389412A1; AT353581B; JPS53140667A; JPS6053660B2; AU3566678A

Abstract

The machine which contains the cutting mechanism and is used in particular for comminuting waste consisting of sheet metal, plastic, glass, wood, textiles and the like has two shafts (5) which are driven in opposite directions at the same speed of rotation and bear cutting bodies of the cutting mechanism which intermesh in pairs. The said cutting bodies have cams (1) and indentations (2) which are distributed uniformly over the circumference and have sharp outer edges. The cams (1) and indentations (2) of the cutting bodies, which are opposite one another in pairs, intersect slightly during operation. In the planar end faces (3) of the cutting bodies, a circulating depression (4) which is matched to the external contour of the said bodies is arranged, the outer limits of the depression being located in the region of the edge zones of the cutting bodies which intersect one another during the operation of the machine. When wear of the edge zones of the cutting bodies has occurred, this permits simple readjustment of the said bodies in the axial direction. <IMAGE>

Description

(54) MACHINE FOR CRUSHING BULK MATERIAL (71) We, BOHMTER MASCHINENFABRIK GmbH & Co. KG., a German Company, of Brockstrape, 4508 Bohmte, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a machine for crushing bulk material such as scrap metal sheet, plastics, glass, wood, textiles and the like.

British patent No. 1,310,057 discloses a machine for crushing bulk material, in particular scrap of metal sheet, plastics, glass, wood, textiles and the like, wherein cutting members which co-operate in pairs are arranged on two shafts which are driven in opposite directions at the same speed of rotation, each of the cutting members having a respective flat end face with projections which are uniformly distributed on the periphery thereof and with recesses provided between the projections, wherein the projections and the recesses are so shaped and the shafts carrying the cutting members are arranged at such a spacing from each other that the sharp outside edges of the projections and recesses of the respectively cooperating cutting members, which sharp outside edges delimit the flat end faces, slightly overlap, in each phase of a revolution, between the two shafts.

It has now been found that the marginal portions of the flat cutting member end faces, which portions overlap in operation of such machines, are subject to a higher degree of wear than the inner regions of such faces, so that it is no longer certain that material fed to the machines is reliably crushed, after the machine has been in service over a prolonged period. Adjustment of the sets of cutting members in the axial direction, on or with their shafts, is possible only within limits, as the cutting edges of the cutting members then engage the end faces of the cutting members which co-operate thereon and which are arranged on the other shaft, and they necessarily become rounded off. When that happens, it is either necessary to surface grind the end faces again, or even to replace the cutting members.

The invention is therefore based on the problem of constructing the cutting members for crushing machines of the kind mentioned above, in such a way that a severe degree of wear of the cutting member marginal portions which overlap in operation of the machine cannot have a disadvantageous effect on the function of the machine.

Accordingly the present invention provides a machine for crushing bulk material such as scrap metal sheet, plastics, glass, wood, textiles and the like, wherein at least two cutting members which co-operate are arranged on two shafts which are drivable in opposite directions at the same rotational speed, each of the cutting members having a respective flat end face with at least two projections which are uniformly distributed on the periphery thereof and with recesses provided between the projections, wherein the projections and the recesses are so shaped and the shafts carrying the cutting members are arranged at such a spacing from each other that sharp outside edges of the projections and recesses of the respectively cooperating cutting members, which sharp outside edges delimit the flat end faces, slightly overlap, in each phase of a revolution, between the two shafts, a respective depression which extends around the respective cutting member in the flat end face thereof and which is adapted to the outside configuration of that cutting member being provided in the flat end face of each cutting member, and the outer boundaries of the depressions being disposed in the region of the cutting member marginal portions which overlap in operation of the machine.

Because of these depressions, the outer marginal portions of the cutting member end faces, which outer marginal portions are disposed outside the depressions, appear in the form of projecting edges. After wear has occurred, these edges of each two co-operating cutting members can be adjusted again for cutting by a simple operation of adjustment in the axial direction, without the cutting edges of the cutting members engag ing in the end faces of the co-operating .members. In this way, by simple axial adjustment, the cutting members can be used until the marginal portions of the cutting member end faces, which marginal portions lie outside the depressions, no longer project relative to the depressions.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompany drawing, in which: Figure 1 is an end view of a cutting member of the machine of the invention, and Figure 2 is a view in cross-section taken along line II II of Figure 1.

A machine of the invention, for crushing bulk material such as scrap metal sheet, plastics, glass, wood, textiles and the like, has at least two cutting members, and advantageously more, arranged in pairs, on two shafts which are drivable in opposite directions at the same rotational speed. Each of these cutting members, as shown in the drawing, has a respective flat end face 3, at least two, and in this case, three projections 1 which are distributed uniformly around its periphery, and recesses 2 which are disposed -between the projections 1. Provided in the end face 3 of the -cutting member is a shallow depression 4 which extends around the cutting member, the inner and outer boundaries of the depression 4 being shown in broken lines in Figure 1.

The outer boundary 41 of the depression 4 extends in the region of the marginal portion of the cutting member, which is arranged on a first of the two shafts and which in -operation of the machine is overlapped, in each phase of a revolution, by the marginal portion of a cutting member arranged on the second of the two cutting mechanism shafts.

The projections 1 and the recesses 2 thus are so shaped and the shafts carrying the cutting members are arranged at such a spacing from each other that sharp outside cutting edges of the projections 1 and recesses 2 of the respectively co-operating cutting members, -which sharp outside edges delimit the flat end faces 3 of the cutting members, slightly overlap, in each phase of a revolution, between the two shafts.

The inner boundary 42 of the depression 4 on the other hand extends approximately in the form of a triangle at a certain spacing from a centre bore 5 and blind holes 6 and 7 which are arranged at uniform spacings from each other in the two end faces 3 of the cutting member on a common pitch circle disposed concentrically with respect to the centre bore 5. The blind holes 6 and 7 are provided for receiving connecting pins (not shown) for the respective adjacent cutting members which are arranged on the same shaft. The holes 7 are displaced at from about 8 to 10" relative to the holes 6, corresponding to the relative displacement of the adjacent cutting members on their shafts.

WHAT WE CLAIM IS: 1. A machine for crushing bulk material such as scrap metal sheet, plastics, glass, wood, textiles and the like, wherein at least two cutting members which co-operate are arranged on two shafts which are drivable in opposite directions at the same rotational speed, each of the cutting members having a respective flat end face with at least two projections which are uniformly distributed on the periphery thereof and with recesses provided between the projections, wherein the projections and the recesses are so shaped and the shafts carrying the cutting members are arranged at such a spacing from each other that sharp outside edges of the projections and recesses of the respectively cooperating cutting members, which sharp outside edges delimit the flat end faces, slightly overlap, in each phase of a revolution, between the two shafts, a respective depression which extends around the respective cutting member in the flat end face thereof and which is adapted to the outside configuration of that cutting member being provided in the flat end face of each cutting member, and the outer boundaries of the depressions being disposed in the region of the cutting member marginal portions which overlap in operation of the machine.

2. A machine according to claim 1, wherein blind holes for receiving cutting member connecting pins are arranged in both end faces of the cutting members on a common pitch circle which extends concentrically with respect to centre bore in each cutting member, the blind holes being uniformly spaced from each other.

3. A machine according to claim 2, wherein the blind holes of one cutting member end face are displaced at from about 8" to 10 relative to the blind holes of the other cutting member end face.

4. A machine according to claim 2 or claim 3, wherein an inner boundary of the depression of each cutting member extends at a certain distance from the centre bore and the blind holes provided in the cutting member end face.

5. A machine according to any one of claims 1 to 4, wherein each cutting member has three projections.

6. A machine for crushing bulk material according to claim 1, substantially as hereinbefore described with reference to the accompanying drawing.

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ing in the end faces of the co-operating .members. In this way, by simple axial adjustment, the cutting members can be used until the marginal portions of the cutting member end faces, which marginal portions lie outside the depressions, no longer project relative to the depressions. For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompany drawing, in which: Figure 1 is an end view of a cutting member of the machine of the invention, and Figure 2 is a view in cross-section taken along line II II of Figure 1. A machine of the invention, for crushing bulk material such as scrap metal sheet, plastics, glass, wood, textiles and the like, has at least two cutting members, and advantageously more, arranged in pairs, on two shafts which are drivable in opposite directions at the same rotational speed. Each of these cutting members, as shown in the drawing, has a respective flat end face 3, at least two, and in this case, three projections 1 which are distributed uniformly around its periphery, and recesses 2 which are disposed -between the projections 1. Provided in the end face 3 of the -cutting member is a shallow depression 4 which extends around the cutting member, the inner and outer boundaries of the depression 4 being shown in broken lines in Figure 1. The outer boundary 41 of the depression 4 extends in the region of the marginal portion of the cutting member, which is arranged on a first of the two shafts and which in -operation of the machine is overlapped, in each phase of a revolution, by the marginal portion of a cutting member arranged on the second of the two cutting mechanism shafts. The projections 1 and the recesses 2 thus are so shaped and the shafts carrying the cutting members are arranged at such a spacing from each other that sharp outside cutting edges of the projections 1 and recesses 2 of the respectively co-operating cutting members, -which sharp outside edges delimit the flat end faces 3 of the cutting members, slightly overlap, in each phase of a revolution, between the two shafts. The inner boundary 42 of the depression 4 on the other hand extends approximately in the form of a triangle at a certain spacing from a centre bore 5 and blind holes 6 and 7 which are arranged at uniform spacings from each other in the two end faces 3 of the cutting member on a common pitch circle disposed concentrically with respect to the centre bore 5. The blind holes 6 and 7 are provided for receiving connecting pins (not shown) for the respective adjacent cutting members which are arranged on the same shaft. The holes 7 are displaced at from about 8 to 10" relative to the holes 6, corresponding to the relative displacement of the adjacent cutting members on their shafts. WHAT WE CLAIM IS:

1. A machine for crushing bulk material such as scrap metal sheet, plastics, glass, wood, textiles and the like, wherein at least two cutting members which co-operate are arranged on two shafts which are drivable in opposite directions at the same rotational speed, each of the cutting members having a respective flat end face with at least two projections which are uniformly distributed on the periphery thereof and with recesses provided between the projections, wherein the projections and the recesses are so shaped and the shafts carrying the cutting members are arranged at such a spacing from each other that sharp outside edges of the projections and recesses of the respectively cooperating cutting members, which sharp outside edges delimit the flat end faces, slightly overlap, in each phase of a revolution, between the two shafts, a respective depression which extends around the respective cutting member in the flat end face thereof and which is adapted to the outside configuration of that cutting member being provided in the flat end face of each cutting member, and the outer boundaries of the depressions being disposed in the region of the cutting member marginal portions which overlap in operation of the machine.