Mine Tool Adapter

Abstract

An adapter for mounting a mine tool cutting bit and its holding block on a powered head or chain driven by a mining machine, including a block adapter having a base portion adapted to be affixed to the holding block and a projection extending substantially perpendicularly therefrom. A receptacle portion adapted to be affixed to the powered head or chain of the mining machine has a recess adapted to closely receive the projection extending from the base portion of the block adapter and a shoulder portion upon which the base portion surrounding the projection rests.

Description

BACKGROUND OF THE INVENTION

In the mining of minerals, a variety of mining machines are employed to power beads or chains carrying cutting bits and holders therefor. It is well known to those skilled in the art that mining operations require the frequent replacement of cutting bits and often, the holding blocks as well. These bits and blocks are subjected to excessive wear, abrasion and vibration in the course of cutting the minerals to be extracted from the mine. While there are now available a variety of quick-change bits facilitating the necessary and frequent replacement thereof, the conventional means of attaching the bit holder to the powered head or chain is by welding the holder thereto. Thus, if a bit is permitted to overwear to the point that the holder is also damaged, or due to the excessive vibration and abrasion in the cutting operation, a holder is damaged or split, a considerable effort must be expended to remove the welded block from the powered head or chain for replacement. The replacement of the holding blocks is further complicated by the mine environment of the machinery. The likelihood of the presence of explosive gases and dust within the mine cavities prohibits the utilization of open-flame torches and welding equipment to accomplish the removal of existing blocks and the replacement thereof. Thus, to effect the replacement of a block, the machinery must be removed from the hazardous area which further increases the downtime of the equipment and the expenditure of man hours to effect the necessary repairs.

SUMMARY OF THE INVENTION

Apparatus for attaching a block holding a cutting bit for mining operations to the powered head or chain permitting quick, on site, replacement of the blocks and bits. The adapter includes a base portion to which the cutting block or blocks is affixed and from which a projection extends. The block adapter containing the base and projection are adapted to be received in a receptacle portion having a recess therein adapted to closely receive the projection of the block adapter. The end surface of the receptacle portion is machined to closely engage the base portion around the projection. In the preferred embodiments, the projection and recess are rectangular to restrain any tendency of the block adapter to rotate relative to the receptacle portion, however, other cross sections, such as an oval, may be employed. Further, in the preferred embodiment, a resilient knock-out pin is inserted in a bore drilled through the receptacle portion and the aligned engaged projection, to hold the block adapter within the receptacle portion when the adapter assembly takes an unusual attitude.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of the holding-block adapter and recess portion of the invention.

FIG. 2 illustrates the location of the adapters on a powered wheel or drum of a mining machine.

FIG. 3 illustrates the assembly of FIG. 1.

FIG. 4 shows an alternate embodiment of the invention adapted for use with powered chain mining machinery.

FIG. 5 illustrates the assembly of FIG. 1 with the block adapter and receptacle combination being inverted.

FIG. 6 illustrates the location of the inverted adapters on a powered wheel or drum of a mining machine.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings and FIGS. 1, 2 and 3 in particular, reference numeral 2 indicates a block for holding a cutting bit 4. The block 2 is affixed to a block adapter 6 having base portion 8. Block 2 may be affixed to base 8 by welding, or other methods well known in the art which provide a joint of adequate strength. Affixed to base portion 8 is projection 10 which may be attached by welding or other suitable fastening means, such as bolting. Projection 10 may also be integral with base 8 having been machined out of a larger mass. In the preferred embodiment, projection 10 is substantially centered on base portion 8 such that a surface 12 on the lower side of the base portion surrounds projection 10. Surface 12 is machined flat in the preferred embodiment, though other interlocking mating surfaces might be employed.

A receptacle portion 13 having a recess 14 of a cross section similar to projection 10 is adapted to be mounted on a powered drum 16 such as shown in FIG. 2. The preferred means illustrated for affixing receptacle 13 to drum 16 is by welding, however, it will be readily apparent to those skilled in the art, that drum 16 might be manufactured with receptacles 13 as an integral part thereof. Receptacle 13 exhibits a bearing surface 18 on the mating end thereof which is machined flat to engage surface 12 of base portion 8. In the preferred embodiment, both projection 10 and receptacle 13 contain bores 20, extending laterally therethrough which receive retaining pins 22. Preferably, retaining pin 22 may be a resilient material, for example plastic (e.g. urethane), or a coiled spring of steel or other metal of a diameter slightly larger than bore 20 to provide a slight force fit. Such an arrangement permits rapid removal of pin 22 at time of replacement. It will be noted that a bolt and nut might also be used, however such would destroy some of the "quick-change" feature.

In operation, with receptacle 13 on position on drum 16, cutting bit 4 and holding block 2 may be mounted in the wheel through block adapter 6. Projection 10 in inserted in receptacle 13 being received in opening 14. In the single bit/block embodiment illustrated in FIG. 1, the outside of receptacle portion measures 6 inches by 2 inches, and recess 14 measures 1.005 +0.005 inches by 5.005+0.005 inches. Base 8 of cooperating block adapter 6 measures 6 inches by 2 inches with projection 10 measuring 0.995 +0.005 inches by 4.990 +0.005 inches. It may thus be seen that in this embodiment, the sideplay between projection 10 and receptacle 14 is 0.010 inches and between ends is 0.015 inches, demonstrating the close-fit between projection 10 and receptacle 13.

In the 2 block embodiment disclosed in FIGS. 1 and 3 the overall dimensions are decreased to 2 inches 31/4 inches and those of the projection and receptacle to approximately 1 inch by 2.5 inches, but the tolerances remain the same. When block adapter 6 is received in receptacle 13, pin 22 is inserted through bores 20 in receptacle 13 and projection 10 keeping block adapter 6 in receptacle 13 when the structure assumes an unusual attitude, such as inverted. It is to be noted that when pin 22 is of a resilient material such as hard rubber or plastic, it is incapable of absorbing and transmitting the cutting forces generated in bit 4. The cutting forces F generated at bit 4 are transferred through the block adapter 6 and receptacle 13 by mating surfaces 12 and 17 and the lateral surfaces of projection 10 and recess 14. It will be noted that in the embodiments illustrated, projection 10 has beveled corners and that the comparable corners of recess 14 are rounded. These features facilitate the insertion of block adapter into recess 14 but are not necessary. Likewise, the cross section of the projection 10 is and recess 14 is generally rectangular as illustrated in the figures. This, too, is considered illustrative in that any cross section which will prohibit turning of the adapter 6 within the recess 14 will suffice. Thus a cross section such as elipses, ovals, triangles and squares and considered equivalents.

FIG. 4 illustrates application of the invention in a chain link for operating in a mining machine. Reference to the figure shows similar block adapter structure 6' including a base portion 8' and a projection 10' similar to that described in FIGS. 1 and 2, is received in a recess receptacle portion 13' having a cooperating recess 14', also similar to that shown in FIGS. 1 and 3. In this embodiment receptacle 13' is mounted on a chain link 24 by any suitable means such as welding. It is to be noted here, as well as the embodiments described above, that the chain 24 may be manufactured with the receptacle 13' as an integral portion of the link rather than joined by separate operation.

The material utilized for construction of the adapter 6 and receptacle 12 in the disclosed embodiments was AISI-type 4140 alloy. This, too, is considered illustrative in that there are many other acceptable tool steels which may be employed so long as they meet the strength requirements of the application. It will also be apparent to those skilled in the art that the relative position of the receptacle portion and the base with projection may be reversed such that the receptacle 13 is affixed to the block 2 and the base 8 affixed to drum 16 or chain link 24, as shown in FIGS. 5 and 6.

Claims

I claim:

1. A mining machine comprised of: a cutter bit; a cutter bit holding block; a block adapter having a base affixed to said holding block and a projection extending substantially perpendicular from the central portion of said base; a receptacle having a recess adapted to receive said projection, said projection and said recess for receiving said projection having cross sections which prohibit relative rotational movement between them; means retaining said projection within said recess; and a driven mechanism united with said receptacle, force for cutting being transmitted from said driven mechanism to said holding block through said receptacle and said block adapter.

2. A mining machine according to claim 1 wherein said receptacle is welded to said driven mechanism.

3. A mining machine according to claim 1 wherein said block adapter is welded to said holding block.

4. A mining machine according to claim 1 wherein said receptacle and said driven mechanism are a unitary structure.

5. A mining machine according to claim 1 wherein said projection and said recess have substantially rectangular cross sections.

6. A mining machine according to claim 1 wherein said retaining means is comprised of a resilient pin extending through a bore in said receptacle and said projection.

7. A mining machine according to claim 6 wherein said resilient pin is of a material from the group consisting of hard rubber and plastic.

8. A mining machine according to claim 1 wherein said driven mechanism is a drum.

9. A mining machine according to claim 1 wherein said driven mechanism is a chain.

10. A mining machine according to claim 1 wherein said block adapter has a plurality of holding blocks affixed thereto.

11. A mining machine comprised of: a driven mechanism; a block adapter having a base affixed to said driven mechanism and a projection extending substantially perpendicular from the central portion of said base: a receptacle having a recess adapted to receive said projection. Said projection and said recess for receiving said projection having cross sections which prohibit relative rotational movement between them; means retaining said projection within said recess; a cutter bit holding block welded to said receptacle; and a cutter bit. Force for cutting being transmitted from said driven mechanism to said holding block through said block adapter and said receptacle.