GB2223045A

GB2223045A - Tool holder

Info

Publication number: GB2223045A
Application number: GB8920249A
Authority: GB
Inventors: David Alexander Mccloskey
Original assignee: Sandvik Australia Pty Ltd
Current assignee: Sandvik Australia Pty Ltd
Priority date: 1988-09-07
Filing date: 1989-09-07
Publication date: 1990-03-28
Also published as: GB8920249D0

Abstract

A tool holder apparatus which comprises a cutting tool support (2) which either has a cutting edge or is adapted to support a cutting tool, and a block (6) to releasably retain the cutting tool support. The releasable retaining means includes a tapered wedge (8) compatible with a portion of the tool support and also includes an adjustable means (10-12) to draw the wedge and tool support into secure engagement. <IMAGE>

Description

TOOL HOLDER This invention relates to long wall shearers and road headers and, in particular, to tool holders used therein.

The invention has been developed primarily for use with longwall shearers, and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use.

Longwall shearers and road headers employ a rotating shearer drum which supports a plurality of point attack picks. Each pick is located in a tool support which, in turn, is secured to a block or holder integral with the drum.

Previously known securing means have included a resilient transverse pin. However, this permits relative movement between the tool support and the block. This relative movement causes wear in the components which, in turn, leads to increased relative movement and greater wear.

It is an object of the present invention to provide securing means which reduces wear between the respective components and which permits the take-up of any wear should it occur.

According to the invention, there is provided a tool holding apparatus for releasably retaining a cutting tool support, said apparatus including a tool support having a bottom shank portion and a top portion adapted for cutting or supporting a removable cutting tool, a block having a socket adapted for removably receiving said tool support shank portion, and retaining means whereby said tool support is releasably retained within said socket, said retaining means including a tapered wedge slidably engage able with said shank portion, and adjustable means for drawing said wedge into secure engagement with said shank portion.

Preferably, the tool support shank portion and the socket have complementary tapers.

Preferably, the tapered wedge has a thread engageable with a complementary nut to progressively draw the wedge into secure engagement with a slot in said shank portion.

Preferably also, the slot has a complementary taper adapted for sliding engagement with the tapered wedge.

A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a front elevation of a tool holding apparatus according to the invention.

Figure 2 is a side elevation of the tool support shown in Figure 1 but including a tool.

Figure 3 is a front elevation of the tool support of Figure 2.

Figure 4 is a side elevation of a tapered wedge and eccentric washer as shown in Figure 1.

Figure 5 is a front elevation of the tapered wedge of Figure 4.

Figure 6 is a front elevation of the eccentric washer of Figure 4.

Referring to the drawings, the tool holding apparatus 1 includes a tool support 2 having a bottom shank portion 3 and a top portion 4 supporting a cutting tool 5 which may be removable or formed integrally with the tool support.

The shank portion 3 of the tool support 2 is releasably retained within a socket 7 formed in a block 6 secured to the drum (not shown). The shank portion 3 and the socket 7 have respective complementary tapers 13 and 14.

The tool support is retained within the socket by a tapered wedge 8 which is slidably engageable with a slot 9 in the shank portion 3. The slot 9 and wedge 8 have respective complementary tapers 15 and 16. The tapered wedge 8 has a thread 10 engageable with a nut 11 which bears against an eccentric washer 12. As the nut 11 is engaged with the thread 10, the wedge is progressively drawn into secure engagement with the shank portion, and the tool support is drawn into close abutment with the block, substantially eliminating any relative movement.

Should any wear occur between the tool support and the block, the resulting clearance may be conveniently taken up by retightening the nut 11.

Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Claims

1. A tool holding apparatus for releasably retaining a cutting- tool support, said apparatus including a tool support having a bottom shank portion and a top portion adapted for cutting or supporting a removable cutting tool, a block having a socket adapted for removably receiving said tool support shank portion, and retaining means whereby said tool support is releasably retained within said socket, said retaining means including a tapered wedge slidably engageable with said shank portion, and adjustable means for drawing said wedge into secure engagement with said shank portion.

2. A tool holding apparatus according to Claim 1, wherein said tool support shank portion and the socket have complementary tapers.

3. A tool holding apparatus according to Claim 1 or 2, wherein said tapered wedge has a thread engageable with a complementary nut to progressively draw said wedge into secure engagement with a slot in said shank portion.

4. A tool holding apparatus according to Claim 3, wherein said slot has a complementary taper adapted for sliding engagement with said tapered wedge.

5. A tool holding apparatus substantially as hereinbefore described with reference to the accompanying drawings.