GB2035418A

GB2035418A - Coal cutter picks and pick boxes

Info

Publication number: GB2035418A
Application number: GB7940795A
Authority: GB
Original assignee: Tungsten Carbide Developments Ltd
Current assignee: Tungsten Carbide Developments Ltd
Priority date: 1978-11-30
Filing date: 1979-11-26
Publication date: 1980-06-18

Abstract

A coal cutter pick box (16) having an aperture (14) for the reception of the shank (12) of a coal cutter pick (10) the pick box having aligned slots (20) at opposite sides of the entry end of the aperture said slots having flared mouths tapering down to restricted openings into circular locations (22) for the opposite ends of a cylindrical pin (18) extending through a transverse hole in the shank (12) of the pick and projecting outwards from its opposite sides. The cylindrical pin (18) may be formed by a "roll spring". <IMAGE>

Description

SPECIFICATION An improvement in or relating to coal cutter picks and pick boxes.

The invention relates to coal cutter picks and pick boxes therefor and has for its object to provide an improvement therein.

Various ways have previously been proposed for retaining coal cutter picks in pick boxes, for example retaining means including plungers urged by resilient means into engagement with grooves formed in the shanks of the picks which they are to retain in position. However, such retaining means require to be made with relatively high precision so that the picks are safely retained in position without danger of inadvertent release and so that a substantially pre-determined force is required to secure a pick in its pick box and to release it therefrom.

The object of the invention is to provide a retaining means which inherently is effected very little if at all, by slight dimensional variations between the picks which are to be retained in position thereby.

According to one aspect of the invention, there is provided a coal cutter pick box for the reception of the shank of a coal cutter pick, the pick box having an aperture for the reception of the shank of the pick and having aligned slots at opposite sides of the entry end of the aperture said slots having flared mouths tapering down to restricted openings into circular locations for the opposite ends of a cylindrical pin extending through a transverse hole in the shank of the pick and projecting outwards from its opposite sides.

According to a further aspect of the invention, there is provided a coal cutter pick adapted to be retained in a pick box as described above, that is to say having a shank which can be entered into the aperture in the pick box, the shank having a cylindrical pin extending through a transverse hole in said shank and projecting outwards from the opposite sides thereof, the arrangement being such that when the shank of the pick is entered into the aperture in the pick box the opposite ends of the pin enter the flared mouths of the slots at the opposite sides of the entry end of the aperture. The cylindrical pin extending through the transverse hole in the shank of the pick may be formed by a so-called "roll spring".

In order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a part-sectional side view of a pick and pick box combination embodying the invention, Figure 2 is a sectional view on the line 2-2 in Figure 1,and Figure 3 is a sectional view on the line 3-3 in Figure 1.

Referring now to the drawings, the coal cutter pick 10 there illustrated is shown to be provided with a shank 12 of rectangular cross section which is received in an aperture 14 of complementary shape in a pick box 16.

A cylindrical pin 18, formed by a so-called "roll spring", extends transversely through the shank 12 of the pick, and when the pick is located in position in the pick box the opposite ends of the pin are engaged in aligned slits 20 which are formed at opposite sides of the entry end of the aperture 14 of the pick box. The slots 20 each have a flared mouth tapering down to a restricted opening into a circular location 22 for the cylindrical pin, the arrangement being such that when the shank of the pick has been entered into the aperture of the pick box it can be forced into its fully engaged position so that the opposite ends of the pin are engaged in the circular locations to retain the pick in its working position.

It will be seen that the pick retaining means are of very simple form and it has been found that this form of retaining means is very effective yet relatively cheap to produce and trouble free in use. It will be understood that the fact that the cylindrical pin 18 is formed by a so-called "roll spring" allows a relatively wide degree of tolerance in the various dimensions of the pick and pick box. That is to say, the resilience of the roll spring would allow for the slots 20 not being aligned exactly with the centre line of the aperture 14, and would allowforthe hole through which the roll spring extends not exactly coinciding with the centre line of the pick shank.

1. A coal cutter pick box for the reception of the shank of a coal cutter pick, the pick box having an aperture for the reception of the shank of the pick and having aligned slots at opposite sides of the entry end of the aperture said slots having flared mouths tapering down to restricted openings into circular locations for the opposite ends of a cylindrical pin extending through a transverse hole in the shank of the pick and projecting outwards from its opposite sides.

2. A coal cutter pick adapted to be retained in a pick box as claimed in claim 1, that is to say having a shank which can be entered into the aperture in the pick box, the shank having a cylindrical pin extending through a transverse hole in said shank and projecting outwards from the opposite sides thereof, the arrangement being such that when the shank of the pick is entered into the aperture in the pick box the opposite ends of the pin enter the flared mouths of the slots at the opposite sides of the entry end of the aperture.

3. A coal cutter pick according to claim 2, in which the cylindrical pin extending through the transverse hole in the shank of the pick is formed by a so-called "roll spring".

4. In combination, a coal cutter pick box as claimed in claim 1 and a coal cutter pick according to either one of claims 2 and 3, the shank of the pick being retained in the aperture in the pick box by the opposite ends of the cylindrical pin extending through the shank being received in the circular locations in the pick box.

5. A coal cutter pick box constructed, arranged and adapted to be used to locate a coal cutter pick, substantially as hereinbefore described with referpence to and as illustrated by the accompanying

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION An improvement in or relating to coal cutter picks and pick boxes. The invention relates to coal cutter picks and pick boxes therefor and has for its object to provide an improvement therein. Various ways have previously been proposed for retaining coal cutter picks in pick boxes, for example retaining means including plungers urged by resilient means into engagement with grooves formed in the shanks of the picks which they are to retain in position. However, such retaining means require to be made with relatively high precision so that the picks are safely retained in position without danger of inadvertent release and so that a substantially pre-determined force is required to secure a pick in its pick box and to release it therefrom. The object of the invention is to provide a retaining means which inherently is effected very little if at all, by slight dimensional variations between the picks which are to be retained in position thereby. According to one aspect of the invention, there is provided a coal cutter pick box for the reception of the shank of a coal cutter pick, the pick box having an aperture for the reception of the shank of the pick and having aligned slots at opposite sides of the entry end of the aperture said slots having flared mouths tapering down to restricted openings into circular locations for the opposite ends of a cylindrical pin extending through a transverse hole in the shank of the pick and projecting outwards from its opposite sides. According to a further aspect of the invention, there is provided a coal cutter pick adapted to be retained in a pick box as described above, that is to say having a shank which can be entered into the aperture in the pick box, the shank having a cylindrical pin extending through a transverse hole in said shank and projecting outwards from the opposite sides thereof, the arrangement being such that when the shank of the pick is entered into the aperture in the pick box the opposite ends of the pin enter the flared mouths of the slots at the opposite sides of the entry end of the aperture. The cylindrical pin extending through the transverse hole in the shank of the pick may be formed by a so-called "roll spring". In order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a part-sectional side view of a pick and pick box combination embodying the invention, Figure 2 is a sectional view on the line 2-2 in Figure 1,and Figure 3 is a sectional view on the line 3-3 in Figure 1. Referring now to the drawings, the coal cutter pick 10 there illustrated is shown to be provided with a shank 12 of rectangular cross section which is received in an aperture 14 of complementary shape in a pick box 16. A cylindrical pin 18, formed by a so-called "roll spring", extends transversely through the shank 12 of the pick, and when the pick is located in position in the pick box the opposite ends of the pin are engaged in aligned slits 20 which are formed at opposite sides of the entry end of the aperture 14 of the pick box. The slots 20 each have a flared mouth tapering down to a restricted opening into a circular location 22 for the cylindrical pin, the arrangement being such that when the shank of the pick has been entered into the aperture of the pick box it can be forced into its fully engaged position so that the opposite ends of the pin are engaged in the circular locations to retain the pick in its working position. It will be seen that the pick retaining means are of very simple form and it has been found that this form of retaining means is very effective yet relatively cheap to produce and trouble free in use. It will be understood that the fact that the cylindrical pin 18 is formed by a so-called "roll spring" allows a relatively wide degree of tolerance in the various dimensions of the pick and pick box. That is to say, the resilience of the roll spring would allow for the slots 20 not being aligned exactly with the centre line of the aperture 14, and would allowforthe hole through which the roll spring extends not exactly coinciding with the centre line of the pick shank. CLAIMS

5. A coal cutter pick box constructed, arranged and adapted to be used to locate a coal cutter pick, substantially as hereinbefore described with referpence to and as illustrated by the accompanying drawings.

6. A coal cutter pick constructed, arranged and adapted to be located in a cutter pick box, substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.