GB2042367A

GB2042367A - Roller crushing mill

Info

Publication number: GB2042367A
Application number: GB8004266A
Authority: GB
Original assignee: Gebr Pfeiffer AG
Current assignee: Gebr Pfeiffer AG
Priority date: 1979-02-09
Filing date: 1980-02-08
Publication date: 1980-09-24
Also published as: DE2905025A1; FR2448388A1; JPS55106550A

Abstract

This invention concerns a roller crushing mill comprising a grinding pan 3 Fig. 1 arranged in a mill housing 1 for rotation about a vertical axis 2 thereof, and crushing rollers 5, 6, 7 Fig. 2 for rolling and pressing on the pan 3. The rollers 5, 6, 7 are carried and guided by thrust members 8, 9, 10 which in turn are acted on by a thrust ring 11. The thrust members 8, 9, 10 are arranged inwardly of the rollers and towards the vertical central axis of the mill so that air flow through annular nozzle 13 for grading and delivering milled material upwardly to a sieve is undisturbed. Spring loading takes place against a central pillar 14 rotatable with the same peripheral speed as the thrust members. Alternatively a stationary central pillar can be used. <IMAGE>

Description

SPECIFICATION Roller crushing mill This invention relates to roller crushing mills.

Roller crushing mills usually have a grinding pan rotatable about a vertical axis arranged in a mill housing, and crushing rollers, fixed on thrust members for rolling on and pressing on the grinding pan.

In the known roller crushing mills of this type the crushing rollers are rotatably mounted on thrust members, which are acted on by a thrust ring, on which the bearing pressure is exerted through springs or hydras lically. These thrust members are located outwardly of the crushing rollers. This implies an additional roller requirement. In particular, however, the air current, delivered through a nozzle ring surrounding the grinding pan, which serves to deliver the milled goods upwardly through the mill housing to a sieve, is significantly disturbed, and this adversely affects the function of the air current.

This invention seeks to find ways and means of arranging the thrust members of the crushing rollers, with the greatest possible economy of space, so that the air flowing through the nozzle ring can flow as undisturbed as possible through the milled goods in suspension above the nozzle ring.

Accordingly this invention provides a roller crushing mill comprising a grinding pan arranged in a mill housing for rotation about a vertical axis thereof, and crushing rollers for rolling and pressing on the pan, said rollers being carried and guided by thrust members, wherein the thrust members are arranged inwardly of the rollers and towards the vertical central axis of the mill.

A functionally correct support of these inner located thrust members on the thrust ring is equally possible and ensured as with outer located thrust members. The air flowing into the mill housing from the nozzle ring surrounding the grinding pan no longer however meets any obstacles in the shape of these thrust members. The air current has an undisturbed access to the milled goods above the nozzle ring so that a better grading of the same results. The avoidance of disturbing influences on this air current leads at the same time to an appropriate economy of energy in the mill compressor. Finally the susceptibility to wear, at the sensitive positions of the thrust members, which are now carried from the air current is substantially reduced.

With the new arrangement of the thrust members inside the mill crushing rollers towards the centre of the mill there results likewise new possibilities for the spring-loading of the thrust members. This spring-loading can take place either as mutually opposing or also a spring-loading is possible against a rotating or stationary central pillar.

In each case the spring-loading is more constructionally simple and therefore a cheaper solution than having the thrust pieces located outwardly of the mill crushing rollers, viewed from the centre of the mill.

This invention will now be further described, by way of example only, with reference to the accompanying schematic drawings in which, Figure 1 is a vertical section through one embodiment of a roller crushing mill; and Figure 2 is a plan view along the line ll-ll of Fig. 1.

Referring to the drawings, a grinding pan 3 rotatable about a vertical central axis 2 is arranged in a mill housing 1, the pan being driven in any suitable and known manner.

Crushing rollers 5, 6 and 7 roll on the grinding bed 4 of the rotatable grinding pan 3 (wherein the crushing roller 6 in Fig. 1 is illustrated turned through 60 in the plane perpendicular to the plane of the drawing).

The crushing rollers 5, 6, 7, are held and guided by thrust members 8, 9 and 1 0.

These thrust members 8, 9 and 10 are acted upon by a thrust ring 11 which in turn can be acted upon by suitable pressure means, for example hydraulically. A traction rod 1 2 (see Fig. 1) of such hydraulic means.

A nozzle ring 1 3 encircles the grinding pan 3, through which ring an air current is supplied from under the mill housing 1, which current grades the material milled in the grinding bed 4 and delivers this upwardly through the mill housing 1 to a sieve (not shown) on the mill housing. The sieve may be of any suitable construction.

In accordance with the invention the thrust members 8, 9 and 10 for the crushing rollers 5, 6 and 7 are arranged inwardly of the crushing rollers towards the vertical central axis 2 of the mill. In addition to the advantage of the air current supplied through the ring 1 3 being able to reach the grinding bed 4 undisturbed, there is also the possibility of a simple spring-loading of the thrust members. Such a spring-loading can, for example, take place through the mutual opposition of thrust members 8, 9 and 10. In the embodiment illustrated the spring loading'takes place against a central pillar 1 4 rotatable with the same peripheral speed as the thrust members.

It is also envisaged that this can be achieved using a stationary central pillar.

1. A roller crushing mill comprising a grinding pan arranged in a mill housing for rotation about a vertical axis thereof, and crushing rollers for rolling and pressing on the pan, said rollers being carried and guided by thrust members, wherein the thrust members are arranged inwardly of the rollers and towards the vertical central axis of the mill.

2. A mill as claimed in claim 1, wherein

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Roller crushing mill This invention relates to roller crushing mills. Roller crushing mills usually have a grinding pan rotatable about a vertical axis arranged in a mill housing, and crushing rollers, fixed on thrust members for rolling on and pressing on the grinding pan. In the known roller crushing mills of this type the crushing rollers are rotatably mounted on thrust members, which are acted on by a thrust ring, on which the bearing pressure is exerted through springs or hydras lically. These thrust members are located outwardly of the crushing rollers. This implies an additional roller requirement. In particular, however, the air current, delivered through a nozzle ring surrounding the grinding pan, which serves to deliver the milled goods upwardly through the mill housing to a sieve, is significantly disturbed, and this adversely affects the function of the air current. This invention seeks to find ways and means of arranging the thrust members of the crushing rollers, with the greatest possible economy of space, so that the air flowing through the nozzle ring can flow as undisturbed as possible through the milled goods in suspension above the nozzle ring. Accordingly this invention provides a roller crushing mill comprising a grinding pan arranged in a mill housing for rotation about a vertical axis thereof, and crushing rollers for rolling and pressing on the pan, said rollers being carried and guided by thrust members, wherein the thrust members are arranged inwardly of the rollers and towards the vertical central axis of the mill. A functionally correct support of these inner located thrust members on the thrust ring is equally possible and ensured as with outer located thrust members. The air flowing into the mill housing from the nozzle ring surrounding the grinding pan no longer however meets any obstacles in the shape of these thrust members. The air current has an undisturbed access to the milled goods above the nozzle ring so that a better grading of the same results. The avoidance of disturbing influences on this air current leads at the same time to an appropriate economy of energy in the mill compressor. Finally the susceptibility to wear, at the sensitive positions of the thrust members, which are now carried from the air current is substantially reduced. With the new arrangement of the thrust members inside the mill crushing rollers towards the centre of the mill there results likewise new possibilities for the spring-loading of the thrust members. This spring-loading can take place either as mutually opposing or also a spring-loading is possible against a rotating or stationary central pillar. In each case the spring-loading is more constructionally simple and therefore a cheaper solution than having the thrust pieces located outwardly of the mill crushing rollers, viewed from the centre of the mill. This invention will now be further described, by way of example only, with reference to the accompanying schematic drawings in which, Figure 1 is a vertical section through one embodiment of a roller crushing mill; and Figure 2 is a plan view along the line ll-ll of Fig. 1. Referring to the drawings, a grinding pan 3 rotatable about a vertical central axis 2 is arranged in a mill housing 1, the pan being driven in any suitable and known manner. Crushing rollers 5, 6 and 7 roll on the grinding bed 4 of the rotatable grinding pan 3 (wherein the crushing roller 6 in Fig. 1 is illustrated turned through 60 in the plane perpendicular to the plane of the drawing). The crushing rollers 5, 6, 7, are held and guided by thrust members 8, 9 and 1 0. These thrust members 8, 9 and 10 are acted upon by a thrust ring 11 which in turn can be acted upon by suitable pressure means, for example hydraulically. A traction rod 1 2 (see Fig. 1) of such hydraulic means. A nozzle ring 1 3 encircles the grinding pan 3, through which ring an air current is supplied from under the mill housing 1, which current grades the material milled in the grinding bed 4 and delivers this upwardly through the mill housing 1 to a sieve (not shown) on the mill housing. The sieve may be of any suitable construction. In accordance with the invention the thrust members 8, 9 and 10 for the crushing rollers 5, 6 and 7 are arranged inwardly of the crushing rollers towards the vertical central axis 2 of the mill. In addition to the advantage of the air current supplied through the ring 1 3 being able to reach the grinding bed 4 undisturbed, there is also the possibility of a simple spring-loading of the thrust members. Such a spring-loading can, for example, take place through the mutual opposition of thrust members 8, 9 and 10. In the embodiment illustrated the spring loading'takes place against a central pillar 1 4 rotatable with the same peripheral speed as the thrust members. It is also envisaged that this can be achieved using a stationary central pillar. CLAIMS

2. A mill as claimed in claim 1, wherein the thrust members are spring-loaded.

3. A mill as claimed in claim 2, wherein the thrust members are mutually opposingly spring-loaded.

4. A mill as claimed in claim 2, wherein the thrust members are spring-loaded against a central pillar arranged in the vertical central axis of the mill.

5. A mill as claimed in claim 4, wherein the central pillar is rotatable.

6. A mill as claimed in claim 4, wherein the central pillar is stationary.

7. A roller crushing mill substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.