GB2243857A

GB2243857A - A cutting appliance for mounting on an arm of a cutting machine

Info

Publication number: GB2243857A
Application number: GB9108549A
Authority: GB
Inventors: Willi Klingbeil; Hans Gunter Follert
Original assignee: Gewerkschaft Eisenhutte Westfalia GmbH
Current assignee: Gewerkschaft Eisenhutte Westfalia GmbH
Priority date: 1990-05-08
Filing date: 1991-04-22
Publication date: 1991-11-13
Anticipated expiration: 2011-04-22
Also published as: ITGE910062A0; ATA75291A; GB9108549D0; IT1248795B; GB2243857B; ITGE910062A1; AT399201B; DE4014752A1; DE4014752C2

Abstract

A cutting appliance for fitment to a ranging arm (1) of a partial cutting machine employs a rotating cutting head (6) connected to a sleeve (15) surrounding a stationary hollow support (2) with bearings (16, 17) locating between the support (2) and the sleeve (15). A drive shaft (7) extends through the support (2) and is rotatably coupled to the head (6) and to drive moans (5) within the arm (1). A helical-flight conveyor (24), surrounds the sleeve and is rotatable with the sleeve (15) and the cutting head (6). <IMAGE>

Description

1 A CUTTING APPLIANCE FOR MOUNTING ON AN ARM OF A CUTTING MACHINE The

present invention relates to a cutting appliance for use with partial cutting machines used for tunnelling and mining. As is known, such machines employ a longitudinal arm which ranges up and down and from side to side. A cutting head at the free end of the arm is then used to detach material from a working face. The cutting head can extend transversely or longitudinally of the arm. (See Gluckauf 1981 p. 284-287 and Gluckauf 1984 p. 15341539. It is also known to use a helical-flight conveyor to transfer or load material detached ftom the working face. In some cases the conveyor helix is mounted on the longitudinal cutter head in such a way as to form an extension of the latter towards the rear. (See Gluckauf, 1983, p. 501-508).

Known longitudinal cutting arms usually have an integrated cutter head drive. This generally involves a motor mounted inside the cutting arm and a drive shaft which passes through a cutting arm carrier screwed onto the head of the cutting arm and mounted in roller bearings in the carrier. As the cutter head when in use is subjected to considerable working forces and loading, the resultant forces have to be transmitted as transversal forces to the shaft and dissipated in its bearings. These bearings thus need to be made very strong. If the rearward prolongation of the cutter head takes the form of 2 a conveyor helix rotating with the latter and surrounding its carrier, the unilateral loads on the cutter head may cause the latter to tilt so that the end of the base of the helix which is next to the machine slides along one side only of the cutter head carrier, moving so far away from its'other side that the gap between conveyor helix and cutter head carrier is no longer reliably sealed.

An object of the invention is to provide an improved cutting appliance.

According to the invention there is provided a cutting appliance for mounting on an arm of a cutting machine; said appliance comprising a drive shaft, a cutting head rotatably coupled to the drive shaft, the drive shaft being adapted to be driven by drive means within the arm of the cutting machine, an elongate support for fixing to the arm, the support surrounding the drive shaft, and a sleeve mounted for rotation with the cutting head on bearings carried by the support.

Operating forces can be reliably absorbed by the bearings serving for the mounting of the cutter head. The support now constitutes the free end of the cutting arm and is preferably formed by a component detachably affixed to the cutting arm directly or indirectly as a prolongation thereof, for preference by means of a screw connection.

In accordance with the invention, the drive shaft of the cutter head does not have to be mounted directly on 3 shaft bearings provided in the cutting arm or in a cutting head carrier. On the contrary, the cutter head together with the drive shaft is mounted by means of bearings, preferably rolling-element, e.g. roller bearings, which are situated apart from the cutting arm or cutter head and between the support and the aforementioned rotary sleeve of the cutter head. Such bearings, with accordingly increased diameters, are more capable of absorbing the operating forces. The drive shaft is no longer subjected to any unfavourable transversal forces or bending stresses. Instead, the cutter head is supported and mounted by means of the robust rotary sleeve which surrounds the cutter head support. An appliance in accordance with the invention also renders the externally situated bearings more easily accessible for insertion or removal and replacement. The sleeve can also serve as a support for a helical-flight conveyor. Such a conveyor can comprise a cylindrical base part carrying a helical flight. The conveyor is advantageously connected to the cutter head by its cylindrical carrier or base tube surrounding the rotary sleeve and by a positively locking joint e.g. composed of axial projections and apertures.

The cylindrical carrier of the conveyor can engage an annular recess on the exterior surface of the cutter head which is preferably frusto-conical and on a shoulder of the sleeve.

4 The appliance can be so arranged that the rotary sleeve is detachably connected with the cutter head, e.g. by a screw connection, preferably with the use of studs passing axially through the cutter head. This latter and the rotary sleeve are thus detachably interconnected and can be separated from each other, so that the assembly and dismantling of the parts is thus made easier.

As a further advantageous development of the invention the drive shaft can be insertable from the end nearer to the cutter head into the elongate support and has an inner end which can be coupled fast in rotation with a drive coupling of the cutter head drive on the sliding coupling principle. The shaft and drive coupling may have inter- engageable splines or teeth to achieve the sliding coupling. The drive shaft can thus be pushed into the cutter head carrier from the front, with the cutter head detached, and connected fast in rotation with the cutter head drive or withdrawn therefrom.

The appliance is advantageously designed in such a way that the drive shaft also has an end which is nearer to the cutter head and which has an axial series of splines or teeth or the like, which engage an internal boring in the cutter head and which is axially toothed in a corresponding manner. Between the cutter head and that part of the drive shaft which faces towards it a spring device can be mounted in the cutter head to act on the shaft. This offers the advantage of preventing displacement of the driving shaft in the axial direction.

With a view to the simplification of the assembly and dismantling of the cutter head and of the associated parts, it is of advantage if the rotary sleeve is attachable from the cutter head side to the support and is held by means of the screw connection in the position in which it has been installed. The bearings are advantageously secured in their axial spaced location by annular shoulders provided on the cutter head support and on the rotary sleeve and also by a detachable securing plate provided on the end of the cutter head support.

It is also desirable to provide one or more seals or packings which seal the annular gap between the rear end of the rotary sleeve and the cutter head support. Further seals or packings are cylindrical base of the which the The conveyor is invention preferably provided between the conveyor and the rotary sleeve on supported.

may be understood more readily, and various other.aspects and features of the invention may become apparent, from consideration of the following description.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawing, wherein:

Figure 1 is a longitudinal sectional side view of part of a cutting appliance constructed in accordance with 6 the invention; and Figure 2 is a sectional detail view of part of the cutting appliance depicted in Figure 1.

As represented in the drawing, a cutting appliance is associated with a longitudinal arm I which is only partly shown. The: arm 1 is supported in known manner on a carrier, such as a partial-cutting machine, of a machine which can cause the arm I to swing up and down and from side to side to cause the appliance to sweep over a working face.

The front end of the arm 1, nearest a cutting head 6, is detachably coupled to a hollow elongate support 2 with the aid of a cup-shaped connection piece 4. Screws.3 (some of which are merely indicated as chain- dotted lines) are used to fix the connection piece 4 to the arm 1 and to the support 2. The arm 1 contains drive means 5 for driving the cutter head 6 and the drive means 5 can take the form of a drive motor, a clutch and gearing. The drive means 5 is coupled to the head 6 with the aid of a drive shaft 7 which passes through the support 2. The shaft 7 is designed to be installed into the support 2 from the end nearest the cutting head 6 and has an inner end region 8 which drivably locks with a coupling 9 of the drive means 5. The coupling 9 can take the form of an internally splined or toothed component into which the similarly constructed toothed or splined end region 8 of the shaft 7 engages. The opposite end region 10 of the 7 shaft 7 is likewise provided with external teeth or splines which fit into an internally toothed or splined bore 11 of the cutting head 6. The cutting head is of frusto-conical configuration equipped in the usual way with cutter bits 12 fitted into holders. A blind bore 13 in the cutter head 6 contains a spring 14 which engages on the drive shaft 7 and urges the shaft 7 rearwardly to maintain the drive via the drive connection 8,9.

The shaft 7 does not contact the support 2 and there are no bearings between these components. Instead, a robust sleeve 15, which rotates with the cutting head 6, surrounds the support 2 and rolling-element bearings 16, 17 are provided between the sleeve 15 and the support 2. The sleeve 15 is detachably connected to the head 6 with the aid of screws 18 merely shown as chain-dotted lines. The cutting head 6 and the sleeve 15 thus rotate as a unit on the bearings 16, 17 carried by the support 2 which forms a prolongation of the arm 1. The inner ring of the bearing 16 abuts on an annular shoulder 19 of the support 2 and the outer ring of the bearing 16 abuts on an annular shoulder 20 of the sleeve 15. The other bearing 16 has its outer ring abutting on an annular shoulder 21 of the sleeve 15, whilst its inner ring abuts on a disc or plate 22 detachably secured to the support 2, with the aid of a lock nut 22 screwed on a threaded portion of the support 2.

The sleeve 15 carries a helical conveyor 24 composed 1 8 of a continuous helical flight 28 on a cylindrical base part 25 which engages at zones 26,27 on the sleeve 15. The cylindrical part 25 is connected to the cutting head 6 and for this purpose the part 25 has a reinforced attachment 29 which engages in a recess 30 in the head 6. As shown in Figure 2, the attachment 29 has axial toothlike projections 31 distributed around its periphery and engaging in apertures 32 in the base of the recess 30 to provide a positive drive connection between the conveyor 24 and the head 6. The part 25 of the conveyer 24 can be placed over the sleeve 15 to locate on an abutment shoulder 33 of the sleeve 15 to thereby ensure that when the head 6 is mounted the conveyor 24 is fixed axially as well as for rotation with the sleeve 15 and the cutting head 6.

The annular gap between the sleeve 15 and the support 2 at the end of the arm 1 is sealed with a packing 34 preferably a labyrinth seal and/or a soft metal ring. At the opposite end the annular gap between the sleeve 15 and the support 2 is sealed with a gasket 35 fitted between the plate 22 and the sleeve 2. Further seals 36, 37 are provided between the cylindrical part 25 of the conveyor 24 and the sleeve 15.

The construction as described provides a comparatively simple and rapid means for assembly and dismantling of the cutting head 6 and the drive shaft 7.

9 The assembly steps involve the location of the packing 34 and the bearing 16 on the support 2 and the sleeve 15 with its bearing 17 is then fitted over the support 2 from the cutter head end. The plate 22 is then mounted to fix the sleeve 15 in place axially with the locking nut 23. The seals 35, 36, 37 are then placed in position and the drive shaft 7 is slid into the support 2 from the cutter head end to bring its inner end region 8 into engagement with the drive coupling 9. The cylindrical part 25 of the conveyor 24 is next fitted onto the sleeve 15 to abut on the shoulder 33 and the part 25 is then properly supported on the sleeve 15. Finally, the cutting head 6 is mounted onto the shaft 7 to engage the drive connection 10,11. The head 6 is connected to the sleeve 15 with the screws 18 and the projections 31 of the cylindrical part 25 engage in the apertures 32 in the head 6. The spring 14 between the head 6 and the shaft 7 prevents undue displacement of the shaft 7 axially. The conveyor 24 has a certain limited freedom of axial displacement between the shoulder 33 and the apertures 32.

To dismount the assembly, a reverse sequence from that described can be adopted.

In a modified appliance, the connection piece 4 is omitted and an equivalent integral portion can be provided on the support 2. The support 2 is then simply fixed to the free end of the arm I with a flanged end and the screws 3.

Claims

1. A cutting appliance for mounting on an arm of a cutting machine; said appliance comprising a drive shaft, a cutting head rotatably coupled to the drive shaft, the drive shaft being adapted to be driven by drive means within the arm of the cutting machine, an elongate support for fixing to the arm, the support surrounding the drive shaft, and a sleeve mounted for rotation with the cutting head on bearings carried by the support.

2. A cutting appliance according to claim 1, wherein the sleeve is surrounded by a helical conveyor.

3. A cutting appliance according to claim 2, wherein the conveyor has a helical flight on a cylindrical part surrounding the sleeve.

4. A cutting appliance according to claim 2 or 3 wherein connection means rotatably connects the conveyor to the cutting head.

5. A cutting appliance according to claim 4 wherein the connection meLns takes the form of axial projections on the cylindrical part of the conveyor fitting in apertures in the cutting head or vice versa.

6. A cutting appliance according to claim 3, 4 or 5 wherein the cylindrical part of the conveyor engages on a shoulder of the sleeve.

7. A cutting appliance according to Claim 3 or Claim 4, 5 or 6 when appended to Claim 3 and further comprising one 1 11 or more seals or packings for sealing between the cylindrical part of the conveyor and the sleeve.

8. A cutting appliance according to any one of the preceding claims wherein the support is detachably secured to the arm.

9. A cutting appliance according to any one of the preceding claims wherein the sleeve is detachably secured to the cutting head.

10. A cutting appliance according to any one of the preceding claims wherein the drive shaft is separable and adapted to be inserted into the support and the shaft has an inner end portion relative to the cutting head for engaging with a drive coupling of the drive means.

11. A cutting appliance according to claim 10, wherein the shaft has an outer end portion relative to the cutting head which engages with a drive coupling of the cutting head.

12. A cutting appliance according to claim 9 or 10 wherein the inner or outer end portions of the shaft or both said portions have splines or teeth which mate with similar splines or teeth of the associated drive coupling.

13. A cutting appliance according to claim 9, 10 or 11, wherein a spring device operates between the cutting head and the drive shaft to urge the shaft towards the drive coupling of the drive means.

14. A cutting appliance according to any one of the preceding claims wherein the sleeve is engageable over the I 12 support from the end at which the cutting head is disposed and the sleeve is detachably held in place by means of a securing device fitted to the support.

15. A cutting appliance according to claim 14, wherein the securing device is a plate which abuts on one of the bearings and a locking ring which engages on the plate and is in screw-threaded engagement with the support.

16. A cutting appliance according to claim 15, wherein the plate engages the inner ring of said one bearing and the outer ring of said one bearing engages on a shoulder of the sleeve, and wherein another bearing has its inner and outer rings engaging on shoulders of the support and the sleeve respectively.

17. A cutting appliance according to any one of the preceding claims and further comprising one or more seals or packings for sealing an annular gap between the sleeve and the support.

18. A cutting appliance substantially as described, with reference to and as illustrated in, the accompanying drawing.

19. A partial-cutting machine with a displaceable arm equipped with a cutting appliance according to any one of the preceding claims.

I- Published 1991 at The Patent Office. Concept House, Cardiff Road, Newport, Gwent NP9 111H. Further copies may be obtained from Sales Branch. Unit 6. Nine Mile Point, Cwrafelinfach. Cross Keys. Newport. NP1 7HZ. Printed by Multiplex techniques lid. St Mary Cray. Kent.