GB2054007A

GB2054007A - Water directing means for a cutting machine

Info

Publication number: GB2054007A
Application number: GB7925458A
Authority: GB
Original assignee: RICH SERVICES Inc ROY
Current assignee: RICH SERVICES Inc ROY
Priority date: 1979-07-20
Filing date: 1979-07-20
Publication date: 1981-02-11

Abstract

In a cutting machine for use for example in the cutting of coal, a housing for water jet nozzle is releasably secured within a cylindrical bore (18) provided in the cutting drum. The housing (22) is preferably a sliding fit within the bore (18), and is conveniently retained in position by a staple connector (34). Preferably the housing (22) is capable of being rotated about an axis to enable the housing to be moved into a desired alignment, to ensure that water issuing from a nozzle secured to the housing is correctly directed. <IMAGE>

Description

SPECIFICATION Improvements relating to cutting machinery Description of the Invention: This invention is concerned with improvements relating to cutting machinery, particularly but not exclusively for cutting coal, in which context the invention will hereinafter be described.

A coal cutting machine, for example in the form of a conventional cutting drum, comprises a number of cutting tools in the form of picks extending generally radially from the drum body, the picks being moved one after the other into engagement with the coal face as the head is revolved. There are several different types of pick which attack the coal face in different ways.

Normally a cutting drum will utilise several different types of pick at different positions on its periphery, in accordance with the type of material being cut.

It is conventional practice to duct water through the drum, and direct it towards the cutting tool in the form of a fine spray. This considerably reduces the creation of dust in the operation of the machine.

Conventionally in the manufacture of a cutting drum, a number of slots or recesses are provided at spaced intervals in the vanes of the cutting drum to locate the pick boxes, and adjacent to each there is provided a slot or recess to locate a housing for a water jet nozzle. Conventionally, the housing for the water jet nozzle is located in position by abutment of two faces of the housing against surfaces of the cut out slot, and the housing is welded in position.

Difficulty is encountered in the latter operation, since it is necessary for the housing to be secured to the cutting drum vane in a correct orientation, to ensure that the spray of water issuing from the housing by way of the water jet nozzle is correctly directed in relation to the adjacent pick, Thus, where the slot is not aligned with the pick box with sufficient accuracy, it may be necessary to move the water jet housing from its strict abutment with one or other of the two adjacent surfaces of the vane.

This difficulty is exacerbated by the need to maintain alignment between a bore through which water is ducted outwardly through the cutting drum vane and a bore extending through the housing, and the difficulty of welding around the area of contact between the cutting drum vane and the housing, along a line extending in three dimensions.

According to this invention there is provided a cutting drum comprising a cutting tool and water directing means to direct a jet of water towards the cutting tool, wherein the cutting drum is provided with locating means adjacent to the cutting tool, and the water directing means comprises a housing having means to co-operate with the locating means to locate the housing on the cutting drum in a desired position relative to the cutting tool, retaining means being provided with co-operates with the drum and with the housing to retain the housing in said desired position in relation to the cutting tool.

In this manner, the housing may be mounted on the cutting drum without the requirement of a welding operation.

Preferably said means on the housing cooperates with the locating means in a manner such as to permit relative movement between the housing and the cutting tool whilst the cutting tool is in said desired position. Thus, after having been located in said desired position, relative movement of the housing may be effected, for example to exercise fine control over the direction of issue from the housing of the water jet, in the use of the cutting drum.

Advantageously said permitted relative movement is rotational movement of the housing about an axis, so that the water jet emitted from the housing may be directed accurately towards the adjacent cutting tool.

The retaining means may be operative to prevent such relative movement: thus, when the housing is located in the said desired position, and moved to a correct orientation, the retaining means may be utilised to prevent further movement between the housing and the cutting drum.

Preferably however the cutting drum comprises restraining means to restrain such relative movement between the housing and the cutting drum. Thus, when the housing is located in said desired position, and moved manually to a correct orientation, the restraining means may be effective to prevent or resist undesired or accidental relative movement between the housing and the cutting drum, albeit permitting manual re-adjustment of the housing position should this become necessary.

Conveniently the locating means is afforded by an aperture in the cutting drum, and the means of the housing is afforded by a projection adapted to be inserted into the aperture, both the aperture and the projection conveniently being of circular cross section.

Thus, the aperture may be afforded by, or may be in axial alignment with, a bore in the cutting drum through which, in the use thereof, water is ducted. In such a construction, the restraining means is conveniently afforded by a seal effective between the cutting drum and the housing.

Advantageously, the direction of issue of the water jet from the housing is transverse to the axis of the aperture, whereby the direction of issue of the water jet from the housing may be varied by rotation of the housing relative to the cutting drum. Such a construction is particularly advantageous, where the housing is used in conjunction with a water jet nozzle, which is removably received within an aperture of the housing.

A further difficulty encountered in conventional cutting drums is that, in use, the housing may be struck by pieces of mineral cut from the face being worked, which may cause damage to the housing to an extent where replacement of the housing is necessitated. For example, in constructions of housing utilising a separable water jet nozzle, the housing may be damaged to an extent such that the nozzle is not readily separable from the housing. Replacement of the housing in conventional constructions is a difficult and time consuming operation, and there is a tendency, where such damage is sustained to continue using the cutting drum, notwithstanding the dangers inherent in the reduction in the dust suppression efficiency of the machine.

in accordance with this invention, the retaining means is preferably readily removable, to permit easy removal of the housing from the cutting drum.

For example, the retaining means may be afforded by a staple connector, arms of which are in use inserted through apertures in the cutting drum and which co-operate with the housing to prevent separative movement of the housing from the cutting drum.

Where the facility for relative movement between the housing and the cutting tool whilst the cutting tool is in said desired position is required, conveniently the arms of the staple connector extend in co-operation with a circumferential groove or annular shoulder provided by the housing. However, where this facility is not required, the arms of the staple connector conveniently extend through apertures afforded in the housing, to restrain any significant movement between the housing and the cutting tool when the housing is in its desired position.

There will now be given detailed descriptions, to be read with reference to the accompanying drawings, of two cutting drums which are preferred embodiments of this invention, and which have been selected to illustrate the invention by way of example.

In the accompanying drawings: FIGURE 1 is a schematic sectional view of part of a cutting drum vane comprising conventional water directing means; FIGURE 2 is a schematic sectional view of part of a vane of the cutting drum which is the first embodiment of this invention; FIGURE 3 is a cross sectional view, taken on the lines Ill-Ill of Figure 2; and FIGURE 4 is an exploded perspective view of part of the vane of the cutting drum which is the second embodiment of this invention.

In the conventional system illustrated in Figure 1, a housing 6 for a water jet nozzle 8 is secured in a slot or recess 10 provided in the periphery of a helical vane 12 of the cutting drum. The correct position of the housing 6 is determined by abutting engagement of two mutually perpendicular faces of the housing 6 with corresponding faces of the aperture 10, and the housing is secured in position by welding around the area of contact therebetween. This involves welding along three lines lying in the plane A-B and along three lines lying in the plane C-D.

During the welding operation, the housing 6 is required to be maintained in a correct orientation such that a bore 14 extending in the housing lines up with a feed bore 1 6 extending radially through the vane 12, and maintaining the inclination and angular orientation of the housing 6 such that water issuing from the nozzle 8 is correctly directed towards the adjacent cutting tool.

In the construction which is the first embodiment of this invention, shown in Figures 2 and 3, the vane 12 is provided with a cylindrical bore 18, which extends coaxially with the duct 1 6, and extending transversely through the vane 12 are two parallel bores 20, 20 which extend generally tangential to the cross sectional plane of the bore 18.

The housing 22 is similarly circular in cross section, and is a sliding fit within the bore 18, the housing comprising a projection 24 in the form of a cylindrical stem which is adapted to be received as a sliding fit within the duct 1 6.

Extending through the stem 24 is a bore 26, which opens into a stepped cavity 28, also of circular cross section, extending into the housing 22, the longitudinal axis of the cavity 28 being inclined to the longitudinal axis of the bore 26. The cavity 28 is adapted to receive a water jet nozzle, which may be of conventional form, or may be of the construction described and illustrated in our co-pending application No. 7911979.

The housing 22 is also provided with a circumferential groove 30 which, when the housing is inserted fully into the cavity 18, is in alignment with the two bores 20. Thus, when in this position, the arms 32, 32 of a staple connector 34 may be inserted into the bores 20, 20, restraining the housing against retractive movement from the bore 1 8 by virtue of engagement of said arms 20 with an interior shoulder afforded by the circumferential groove 30.

Located between the housing 22 and the vane 12, in particular in that space bounded by a circumferential chamfer between the bore 1 8 and duct 16, and extending around the stem 24, is a sealing member afforded by a rubber washer 36.

When the housing 22 is fully inserted into the cavity 18, the sealing member 36 is compressed, and retained in its compressed state by the presence of the staple connector 34. The sealing member 36 not only prevents the flow of water from the duct 16 other than through the bore 26 (for example preventing the flow of water between the walls down in the cavity 1 8 and the housing 22) but also restrains rotational movement of the housing 22, for example about the longitudinal axis of the bore 26. Thus, should such angular movement of the housing 22 be required (for example to facilitate small adjustment of the direction of issuance of the jet of water therefrom) this may be effected manually, but accidental movement of the housing 22 from its desired position is restrained by frictional engagement between the housing and the sealing member 36.

In the embodiment illustrated in Figures 2 and 3, should the housing 22 be damaged, for example by being struck with cut mineral material, the staple connected 34 may be withdrawn (for example by a screw driver or the like instrument) and the housing 22 removed from the cavity 18, to be replaced by a similar housing 22.

Additionally, should it be required to change the housing 22 for a different reason (for example if it becomes desirable to change the cutting tools on the cutting drum, and hence necessitates a redirecting of the water jet issuing from the water directing means) this may be accomplished relatively easily.

In the embodiment illustrated in Figure 4, in which the same numerals but with the suffix a have been used for similar parts, the housing 22a is provided with a stem portion 24a, which is provided with circumferential grooves 30a and 37a. This stem portion 24a is adapted to be a tight sliding fit in a counterbore 1 6a/ of the bore 1 6a.

Annular shoulders of the counterbore, and of the stem portion, are of matching frusto-conical shape. Provided in the drum vane 1 2a, so as to extend tangential to the counterbore 1 6a/, are parallel bores 20a.

In the assembly of the embodiment illustrated in Figure 4, an annular seal 42a is positioned on the stem portion 24a so as to engage an underneath surface 23a of the housing 22a. A rubber 0 ring 36a is then mounted in the annular groove 37a, and the housing is inserted into the cylindrical bore 1 8a with the stem portion 24a extending into the counterbore 1 6a. When the frusto-conical base surface of the stem portion 24a seats against the corresponding frusto conical shoulders between the bore 1 6a and the counterbore 1 6a/, the arms of the staple 34a are inserted through the bores 20a, extending generally tangentially into engagement with the annular channel 30a, to restrain movement of the housing 22a from the cutting drum vane.

A water jet nozzle such as that indicated by the numeral 44a in Figure 4 may then be screwed into the stepped cavity 28a.

In the construction illustrated in Figure 4, the seal afforded by the 0 ring 36a is effective to prevent leakage of water from the duct 1 6a around the outside of the stem portion 24a, and through the parallel bores 20a.

However, the seal 42a, whilst also being effective as a seal against flow of water, serves an additional purpose.

On insertion of the housing 22a, into the bore 18a, to an extent such that the channel 30a is in alignment with the parallel bores 20a, the seal 42a must be compressed slightly. Thus, after the staple 34a has been inserted into engagement with the channel 30a, the seal 42a exerts an upward force on the housing 22a, causing the lower face of the channel 30a to be urged into engagement with the arms of the staple 34a. This engagement, together with the compressive engagement between the shampered corner between the bore 1 8a and the counterbore 1 6a/, and with the underside 23a of the housing 22a, is effective to restrain rotation of the housing 22a within the cavity 1 8a. Thus, whereas the housing may be rotated against these forces manually, the housing is unlikely to turn from its desired orientation accidentally.

Claims

1. A cutting drum comprising a cutting tool and water directing means to direct a spray of water towards the cutting tool, wherein the cutting drum is provided with locating means adjacent to the cutting tool, and the water directing means comprises a housing having means to co-operate with the locating means to locate the housing on the cutting drum in a desired position relative to the cutting tool, retaining means being provided which co-operates with the drum and with the housing to retain the housing in said desired position in relation to the cutting tool.

2. A cutting drum according to claim 1 wherein said means on the housing co-operates with the locating means in a manner such as to permit relative movement between the housing and the cutting tool whilst the housing is in said desired position.

3. A cutting drum according to claim 2 wherein said permitted relative movement is rotational movement of the housing about an axis.

4. A cutting drum according to one of claims 2 and 3 wherein the retaining means is operative to prevent such relative movement between the housing and the cutting tool when the housing is in its desired position.

5. A cutting drum according to one of claims 2 and 3 comprising restraining means to restrain such relative movement between the housing and the cutting drum.

6. A cutting drum according to any one of the preceding claims wherein the locating means is afforded by an aperture in the cutting drum, and said means of the housing is afforded by a projection adapted to be inserted into the aperture.

7. A cutting drum according to claim 6 wherein the aperture in the cutting drum and the projection of the housing are of circular cross section.

8. A cutting drum according to claim 7 wherein the aperture is afforded ty. or is axially in alignment with, a bore in the cutting drum through which in the use of the cutting drum water is ducted.

9. A cutting drum according to claim 5, or to any one of claims 6, 7 and 8 as appendant to claim 5, wherein said restraining means is afforded by a seal effective between the cutting drum and the housing.

10. A cutting drum according to any one of claims 6, 7 and 8, or claim 9 as appendant to claim 6, wherein the direction of issue of the water jet from the housing is transverse to the axis of the aperture, whereby the direction of issue of the water jet from the housing may be varied by rotation of the housing relative to the aperture.

11. A cutting drum according to any one of the preceding claims wherein the retaining means is readily removable, to permit removal of the housing from the cutting drum.

12. A cutting drum according to claim 11 wherein the retaining means is afforded by a staple connector, arms of which are in use inserted through apertures in the cutting drum which co-operate with a shoulder or shoulders on the housing to prevent separative movement of the housing from the cutting drum.

13. A cutting drum according to claim 12 wherein the arms of the staple connector extend in co-operation with a circumferential groove or annular shoulder provided by the housing.

14. A cutting drum comprising a cutting tool and water directing means to direct a spray of water towards the cutting tool, constructed and arranged substantially as hereinbefore described with reference to Figures (a) 2 and 3, or (b) Figure 4 of the accompanying drawings.