US3724901A

US3724901A - Cutter chain having increased conveying ability

Info

Publication number: US3724901A
Application number: US00149263A
Authority: US
Inventors: L Rollins
Original assignee: Individual
Current assignee: Joy Manufacturing Co; Citibank NA; Joy Technologies Inc
Priority date: 1971-06-02
Filing date: 1971-06-02
Publication date: 1973-04-03
Anticipated expiration: 1990-04-03

Abstract

A cutter chain and support means therefor and more particularly a mining apparatus cutter chain having a plurality of lug portions integral with links of such a cutter chain for substantially increasing the conveying ability of the chain over the natural conveying ability thereof.

Description

United States Patent 1 Rollins sl l 3,724,901

45| Apr. 3, I973 [54] CUTTER CHAIN HAVING INCREASED CONVEYING ABILITY [76] Inventor: Lester G. Rollins, 650 Forest Lane,

Franklin, Pa. 16323 221 Filed: June 2,1971

[21] Appl. No.: 149,263

Related US. Application Data [63] Continuation-impart of Ser. No. 786,649, June 24,

1968, abandoned.

[52] US. Cl ..299/84, 299/67 [51] Int. Cl. ..E2lc 25/34, E210 35/20 [58] Field of Search ..299/67, 82-84 [56] References Cited UNITED sTATEs PATENTS 7 1,410,503 3/1922 Porter ..299/67 Joy ..299 s3 Joy ..299 83 Primary Examiner-Ernest R. Purser Attorney-E. Wallace Breisch [57] ABSTRACT A cutter chain and support means therefor and more particularly a mining apparatus cutter chain having a plurality of lug portions integral with links of such a cutter. chain for substantially increasing the conveying ability of the chain over the natural conveying ability thereof.

10 Claims, 9 Drawing Figures PATENTEUAPRB 1m 3,724,901 I SHEET 1 OF 3 av VEN r'on LESTER 6. ROLL/NS PATENTEDAPR 3 I975 sum 3 BF 3 D D Qmw sum mum w INVENTOR. LESTER 6. ROLL/NS CUTTER CHAIN HAVING INCREASED CONVEYING ABILITY This application is a continuation-in-part of my copending application Ser. No. 786,649 filed June 24, I968 and now abandoned.

In a mining apparatus which incorporates the principles of this invention a disintegrating head mechanism is used to dislodge mineral from amine vein and is operable to provide mine passageway or room into which the apparatus advances as mining progresses. The disintegrating head mechanism is. pivotally mounted on a mobile base to swing in a vertical plane between the mine roof and floor and includes a rotary drum cutting head assembly which comprises end portions and a centrally located cutter chain spaced between such end' portions. The apparatus also ineludes a conventional loading head for gathering the loose mineral on the mine floor and moving it rearwardly and inwardly toward the forward receiving portion of the conveying means of the apparatus.

The present invention contemplates improvement of such known type of mining apparatus, for examplez-an improved cutter chain aids in removing dislodged mineral from the face shelf during the sumping and shearing phase of a mining operation; and an improved cutter chain drive sprocket structure for superior supporting of the cutter chain.

These and other objects and advantages of this invention will become more readily apparent from the following description and drawings in which:

FIG. 1 is a perspective view partially schematic of a mining machine embodying the principles of this invention;

FIG. 2 is an enlarged view, partly in section, taken on line 2-2 of FIG. 1 and showing the cutter head assembly;

FIG. 3 is an enlarged side view of an alternative cutter chain drive sprocket structure of this invention;

7 FIG. 4 is an enlarged view, partly in section, taken on line 4-4 of FIG. 3;

FIG. 5 is an enlarged plan view of a portion of the cutter chain of this invention;

FIG. '6 is a side view of the portion of the cutter chain illustrated in FIG. 1;

FIG. 7 is a cross-sectional view taken on line 7-7 of FIG. 5;

FIG. 8 is a cross-sectional view taken on line 88 of FIG. 5; and

FIG. 9 is a partial schematic plan view of a portion of another embodiment of a cutter chain embodying the principlesof this invention.

A continuous mining machine, generally designated at 10, which embodies the principles of this invention may assume various forms but for illustrative purposes,

herein comprises a crawler base 14 carrying a frame 16 on which a forwardly extending mining boom 18 is pivotally mounted at the forward end of frame 16 to swing up and down between a mine roof'and a mine floor. A cutting head assembly 24 extends transversely of boom 18 and is rotatably secured thereto at the forward end thereoffPivotally mounted at the forward end of frame 16 and extending forwardly therefrom beneath the boom 18 is a conventional loading head 26 having oscillatory gathering arms 28 for engaging mined mineral and moving such mineral rearwardly and inwardly toward a well known conveying means'30 of the mining machine 10. Conventional fluid jacks (not shown) serve to swing the boom 18 in a vertical plane about the pivot axis thereof and tilt the loading head 26 about the horizontal axis thereof. The fluid 5 jacks have one end thereof secured to the forward end of frame 16 and have the other end thereof secured to I respective rearward lever ends of boom 18 and loading head 26. Motors 36, which are suitable rigidly secured by brackets 38 to boom 18, drive the cutting head assembly 24 in any suitable manner.

As shown in FIG. 2, the cutting head assembly 24, which is rotatably driven by any suitable gearing arrangement, for example, that gearing arrangement shown and illustrated in U. S. Pat. application No. 786,650, filed Dec. 3, l968, and assigned to the same assignee as is this invention, comprises: an endless circulating belt type continuous hinge cutter chain 76 which is symmetrical with respect to the center line of machine 10; hollow cylindrical rotary drum cutting heads 78 which extend outwardly from respective sides of chain 76; and hollow cylindrical rotary drum cutting head extensions 80 which are slidably partially received within respective heads 78 and are selectively hydraulically extendable outwardly therefrom. A cutting head assembly drive shaft which is rotatably supported by a forward portion 74 of a gear casing 56 located at the forward end of boom 18, extends transversely through heads 78 and extensions 80 and rotatably drives the cutting head assembly 24. For a more detailed description of the structure and operation of cutting head assembly 24 and shaft 70 reference is made to the hereinabove mentioned U. S. application Ser. No. 786,650.

At the longitudinal centerline of machine 10 a cutter chain drive sprocket 82 is in splined engagement with shaft 70. Drive sprocket 82 has a plurality of teeth 84 around the outer periphery thereof which drivably engage the cutter chain 76 as hereinafter described. A suitable rear idler sprocket 86 which is rotatable on a shaft 88 which extends transversely of the boom 18 provides well known tensioning and motion reversing means for the cutter chain 76 to form a continuous orbital path therefor. f

Each rotary drum cutting head 78 has a radially outwardly extending flange 106 at the inner ends thereof and a reduced diameter portion thereof forms a chain end supporting seat 108 which extends axially from flange 106 toward the center line of machine 10. Seats 108 extend under a portion of the outer edges of the endless circulating cutter chain 76 and with such a location act to support the bight portion of the cutter chain 76 at the edges thereof where it is trained about the rotary drum cutting heads 78. The relative rotational speeds of the cutter chain 76 and the seats 108 are equal and therefore there is no movement of cutter chain 76 with respect to the seats 108 during the time chain 76 is supported by seats 108. Because of this lack of relative movement there is no wearing between the respective contact surfaces of seats 108 and chain 76.

The cutter chain drive sprocket 82 is dimensioned to provide a root surfaces 110 thereof which lies in approximately the same cylindrical surface as the contact surfaces of the spaced seats 108. With such root surfaces ll0, each link in the bight portion of chain 76 is supported at three areas namely; end supports at the contact surfaces of the spaced seats 108; and a central support at the root surface 110 of the drive sprocket 82. With such a support arrangement deflection of chain 76 is minimized and the maximum bending moment due to cutting loads is reduced over that deflection and bending moment which would develop under the same loading if the chain 76 had only one or two areas of support.

This support arrangement allows the use of cutter chains having a greater chain width to pitch length ratio than previously permitted, for example a chain width to pitch length ratio of four to one, or more. A width to pitch length ratio of no less than four to one is necessary for the construction of a chain width large enough for thepurposes of this invention as hereinafter set forth while maintaining a sufficient flexibility to avoid unreasonably large sprocket diameters. If the chain width to pitch length ratio is less than four to one, the required chain .width would yield a pitch length requiring sprockets too large to be used in a cutter head such as hereinbefore described. The above chain supporting arrangement is fully illustrated and shown in the hereinbefore mentioned U. S. application Ser. No. 786,650.

An alternative cutter chain central support area constructed according to the principles of this invention is shown in FIGS. 3 and 4 and comprises a cutter chain drive sprocket 82 having spaced shoulders 109 thereon at the flanks of teeth 84'. There are no shoulders 109 at the tooth root 110 and the shoulders 109 areso dimensioned that the diameter of the shoulder circles is substantially greater than the diameter of the tooth root circle. With such an arrangement as illustrated in FIGS. 3 and 4, each link in the bight portion of chain 76 is supported at four areas namely; end supports at the contact surfaces of the spaced shoulders 109. With such a four area support arrangement the advantages of the hereinbefore discussed three area support are maintained, however, thefour area support arrangement has additional advantages such as superior wearing ability and reduced breakage compared to the wearing and breakage tendencies present with a three area support arrangement.

Well known screw type continuous conveyor scrolls 118 are secured to the outer periphery of rotary drum cutting heads 78 and to well known supporting sheaths 115 which are secured to the outer end portions of the rotary drum cutting head extensions 80 which is not selectively receivable within cutting head 78. Such sheaths 11S allow the extension and retraction of head extensions 80 while still maintaining a substantially continuous conveying scroll 118 with respect to the scroll 118 on heads 78. Scrolls 118 and the cutting chain 76 have a plurality of suitable bit holders 120 secured adjacent the outer peripheral edges thereof in a suitable spaced orientation to one another. A cutter bit 122 is inserted in each bit holder 120. Cutter bits 122 may be of any suitable type and as shown are plumb bob deep penetrating point attack conical bits. The scrolls 118 are suitably arranged to convey a portion of mineral mined by bits 122 inwardly from such bit location toward the cutting chain 76. End cutter caps 124 are suitably secured to the outer ends of head extensions 80. Bit holders 120 and cutter bits 122 are secured to caps 124 in a suitable spaced orientation to one another.

Referring to FIGS. 5 through 8 the cutter chain 76 comprises a plurality of links 200 which are hingedly connected by means of a continuous hinge generally designated at 202. Hinges 202 are elongated transversely of cutter chain 76 between adjacent links 200 and comprise interfitting hinge portions as hereinafter described in detail which make up a substantially continuous bore 204 through the respective hinges 202 for insertion of elongated cylindrical hinge pins 206 therein.

Each link 200 comprises an elongated plate or body portion 208 having a plurality of elongated partially cylindrical hinge portions axially spaced along the sides thereof. For purposes of description the uppermost side surface of the body portion 208 as viewed in FIG. 5 is designated 214 and the lowermost side surface thereof is designated 216. In addition, inward and outward as used hereinafter shall refer, respectively, to toward and away from the centerline of machine 10.

The hinge portions of links 200 are formed integrally with the body portion 208 or rigidly secured thereto as by welding or the like. Side 214 includes hinge portions 218, 22 0 and 222 extending therealong such that: portions 218 have the outer ends thereof in transverse alignment with the two outer ends of main body 208; portions 220 are spaced inwardly from portions 218 respectively a distance slightly greater than the axial length of portion 218; and portions 222 are similarly spaced inwardly from respective portions 220. Sides 216 include

hinge portions

224, 226 and 228 extending therealong such that: portions 224 are spaced inwardly from the two outer ends of body portion 208 a distance slightly greater than the axial length of portions 218; portions 226 are spaced inwardly from portions 224 a distance slightly greater than the axial length of portions 220; and a longer center portion 228 is symmetrical with respect to the centerline of cutter chain 76 and has the axial endsthereof spaced from adjacent portions 226 a distance slightly greater than the axial length of portions 222. The axial length and cross-sectional configuration of portions 218-222, 224 and 226 I are substantially equal. The cross-sectional configuration of portions 228 is substantially equivalent to the portions hereinabove mentioned and the axial length thereof is greater than the axial length of such portions.

With such an arrangement, as hereinbefore described, of hinge portions 218-228 along

respective sides

214 and 216, a continuous hinge 202 can be formed by aligning the side 216 of an upper link 200 with the side 214 of. a lower adjacent link 200. The position of hinge portions on

sides

214 and 216 of adjacent links 200 are spaced as previously described to allow the respective hinge portions of the upper link 200 to be received in the spaces between the hinge portions of the lower link 200. After such aligning and receiving'of respective hinge portions within the spaces between hinge portions of adjacent links 200, the hinge pin 206 is inserted within the substantially continuous bore 204. Pins 206 are confined within bores 204 by any suitable means, for example keeper pins 231 positioned in bores 204 inwardly adjacent the outer end of link 200.

A centrally located drive sprocket opening 230 is provided in body portion 208 through which a tooth 84 of cutter chain drive sprocket 82 extends to drive the cutter chain 76. Openings 230 may be of any suitable configuration which will permit suitable tooth engagement to drive chain 76. As shown opening 230 is a generally square opening symmetrically located with respect to the centerline of machine 10. The distance between centerlines of links 200 sometimes referred to as the pitch of the chain equals the pitch distance of the teeth 84 of drive sprocket 82.

Cutter chain 76 has a plurality of suitable bit holders 120 (only one of which is shown in FIG. 5) secured thereto in any suitable manner,-for example welding around the peripheral edges of a bit holder l20to join such holder to body portion 208. A cutter bit 122 is inserted in each bit holder 120. The bit holders are positioned in a suitable spaced orientation to one another to mine mineral forwardly of machine and as such there is no requisite that each and every link 200 have a bit holder 120 thereon.

Cutter chain 76 additionally includes a plurality of conveyor flights generally indicated at 232 (only one of which is shown in FIG. 5) which extend transversely of cutter chain 76 between adjacent links 200. Flights 232 are formed from a plurality of aligned lug portions which project upwardly (to the left in FIGS. 6-8) from the working surface of chain 76.

Such lug portions are formed integrally with hinge portions 218-228 or are rigidly secured thereto as by welding or the like and include; lugs 234 which extend along substantially the entire length of

hinge portions

218 and 220 and project upwardly from the side of

such portions

218 and 220 which is nearer to the body portion 208; lugs 236 which extend along substantially the entire length of

hinge portions

224 and 226 and project upwardly from the side of

such hinge portions

224 and 226 which are farther from the body portion 208; lug 238 which extends along substantially the entire length of hinge portion 228 and projects upwardly from the side of hinge portion 228 which is nearer to the body portion 208; and lugs 240 which extends along substantially the entire length of hinge portions 222 and the length intermediate such portions 222. Each lug 240 has the outer ends thereof projecting upwardly from the sides of hinge portions 222 which are nearer the body portion 208 and a portion 242 thereof intermediate the outer ends projecting upwardly from the side 214 of body portion 208. Such portion 242 has the side thereof which is further from body portion 208 concaved radially inwardly at a radius substantially equal to the radius of hinge portion 228. Such a concaved surface of portion 242 cooperates with hinge portion 228 to facilitate the flexibility of cutter chain 76.

Upon assembly of adjacent links 200 in a manner hereinbefore described, lug portions 234 to 240 form conveyor flights 232 which are in spaced relationship to one another to define conveying pockets 233 in cutter chain 76 between adjacent flights 232.

To mine mineral from a mineral face, the operator of machine 10 initially pivots the boom 18 upwardly to a mine roof line. After such initial pivoting the cutter head assembly 24 is sumped forwardly to begin a cut in the mine face. After the sumping is completed the boom 18 is drawn downwardly toward the mine floor until the shear cut of the face is complete. During the sumping and shearing phase it is important that the mined mineral be quickly removed from the face ledge (Le, the transverse shelf area which exists between the old forward face and the newly mined 'forward face until the shear cut is complete upon which area the main mining action occurs). If the mineral is not quickly removed the efficiency of the cutter head assembly 24 is greatly reduced because of increased horsepower demandand slower cutting rate and, additionally, an inordinate'amount of undesirable mineral fines is produced.

To insure the removal of the mined mineral from the ledge and conveying such mineral away from the face, the conveying flights 232 must be constructed to a specific heighth. .The depth of the flights 232 (Le, that distance from the top of flights 232 down to the upper or working surface of body plate 208) determines the conveying capacity of the cutter chain 76. In other words the depth of the flight 232 times the width of the chain 76 times the pitch of the sprocket 82 (Le, the

width of a link 200) determines the maximum volume of mineral which can be conveyed off the shelf by any one link 200. Such a flight depth is arrived at by analytical means which consider: the type of cutter bit 122 used; the operating speed of the cutter head assembly 24; the maximum and minimum volume of mineral which will be dislodged by the cutter chain 76 during a given increment of time at various shear and sump speeds and with the use of different type bits 122; the pattern of bits 122 on the cutter chain 76; and the like. After an evaluation of the above factors an optimum arrangement of elements is decided upon and this arrangement plus the maximum usable operating speed decides the maximum volume of mineral which can be mined by the cutter chain 76 during a give increment of time. This maximum loose volume of mined mineral therefore determines the depth of the flights 232 for the flights must be capable of conveying at least this volume off the shelf in the same given increment of time, for example; a cutter chain 76 having a kerf width of 30 inches and operating at a shear speed of 1 inch per second on a 30 inch ledge will mine 900 cubic inches of mineral per second, therefore, the flights 232 must be so dimensioned as to develop a conveying capacity for chain 76 of at least 1,800 cubic inch per second (1,800 cubic inches is arrived at by doubling 900 cubic inches because the loose mineral volume is approximately twice the solid mineral volume). Chain 76 conveying capacity (cubic inches per second) is defined by the rate of chain travel (inches per second) times the width of chain 76 (inches) times the depth of a flight 232 (inches).

It is to be understood that all cutter chains have a natural conveying capacity without the presence of conveying elements thereon. Such a natural conveying capacity occurs because of: the physical relationship between the cutter chain and the shelf giving rise to a frictional force which develops on the mined mineral therebetween; and the frontal area of the cutter bits and bit holders convey mined mineral in the immediate vicinity thereof. Such a natural conveying capacity is often insufficient to insure the removal of mined mineral from the ledge and conveying of such mineral away from the face. In addition, if point attack conical bits are used as the cutting elements of a mining machine the use of conveying flights 232 is even more necessary for the efficient operation of the mining machine for such bits have a substantially larger cutting capacity in relation to their frontal area.

Preferred embodiments of this invention having been hereinbefore described and herewith illustrated it is to be realized that variations in the specific structure are envisioned and contemplated, such as: flights 232 can comprise lugs which are common to more than one hinge-portion; the lugs do not necessarily have to be in alignment across the width of cutter chain 76, but can be staggered and still ,perform substantially the same function as if they were aligned; the lugs can extend upwardly from the body plate 208 rather than upwardly from the hinge portions as is hereinbefore described; and the four areas of support for the bight portion of chain 76 can deviate from a common cylindrical surface by a substantial misalignment but not sufficient to result in stressing a link beyond the yield point thereof.

One of the variations discussed hereinabove is shown in FIG. 9 which schematically illustrates a portion of cutter chain 76' similar to the cutter chain 76 described hereinbefore with the primary distinction therebetweenv being that the flights 232' thereof are chevron shaped and are formed from staggered lugs 250 which project upwardly from-the body of the links 200'. As shown lugs 250 are located such that each flight 232{ extends the length of two adjacent links 200 and the staggering and length of the lugs 250 on adjacent links provides for flights 232 extending substantially continuously across the width of the cutter chain 76. A pair of adjacent flights 232 define conveying pockets 233' therebetween for conveying removed mineral away from the mine face. As shown, the width of conveying pocket 233' at any point therealong is substantially equal to the distance between adjacent hinges of chain 76; I

Preferred embodiments of this invention having been hereinbefore described and herewith illustrated it is to be realized that variations in the specific structure are envisioned and contemplated without departing from the scope of the invention, for example: flights can be arranged in manners other than as described hereinbefore; the lugs can extend upwardly from the body plate rather than upwardly from the hinge portions as is hereinbefore described; and the four areas of support for the bight portion of chain 76 can deviate from a common cylindrical surface by a substantial misalignment but not sufficient to result in stressing a link beyond the yield point thereof.

It is. therefore respectfully requested that this invention be interpreted-as broadly as possible and limited only by the scope of the appended claims.

What is claimed is:

l. A cutting chain comprising, a plurality of chain sections pivotally connected by parallel hinge pins to form a continuous chain of adjacent ones of said sections, having a transverse width to pitch length ratio greater than four to one, bit blocks carried by at least some of said sections; and said sections having material receiving portions for conveying material cut during movement of said continuous chain in a bedded deposit of material.

2 A cutting chain as specified in claim 1 wherein said conveying is at a rategreater than the loose volume rate of mineral production by said movement of said chain sections in a bedded deposit of mineral.

A cutting chain as specified in claim 1 wherein each of said chain sections connects two of said pins at a plurality of points spaced longitudinally of said ,pins and each of said pins extends the full width of said chain.

4. A cutting chain as specified in claim 1 wherein.

each of said chain sections has a plurality of conveying means spaced along said hinge pins to form said material receiving portions.

5. A cutting chain as specified in claim 4 wherein at least some of said bit blocks extend upwardly from said body portion and the height of said conveying means less than the height of said bit blocks.

6. In a cutting chain as specified in claim 4 the further improvement wherein said conveying means are located on interfitting portions of substantially continuous hinges.

7. An endless cutting chain comprising: a plurality of links, each of said links including a body portion having a transverse width greater than the length thereof, each of said body portions being hingedly connected to adjacent ones of said body portions along axes extending in the direction of said width, respectively; bit blocks carried by at least some of said links; each of said links having a plurality of members extending upwardly from said body portion and in said direction of said width, said members on a plurality of said links forming conveyor means extending substantially continuously in said direction of said width, respectively, and adjacent pairs of said conveyor means spaced laterally from each other to form material receiving portions of a volume to convey material cut during orbital movement of said links in a bedded deposit of material.

8. An endless cutting chain as specified in claim 7 wherein adjacent links have a width to pitch length ratio of at least four to one.

9. An endless cutting chain as specified in claim 7 wherein at least some of said bit blocks extend upwardly from said body portion and the height of said members is less than the height of said bit blocks.

10. In an endless cutting chain as specified in claim 7 wherein said volume has a conveying rate greater than the loose volume of mined mineral produced by said orbital movement of said links in a bedded deposit 0 mineral.

Claims

1. A cutting chain comprising, a plurality of chain sections pivotally connected by parallel hinge pins to form a continuous chain of adjacent ones of said sections, having a transverse width to pitch length ratio greater than four to one, bit blocks carried by at least some of said sections; and said sections having maTerial receiving portions for conveying material cut during movement of said continuous chain in a bedded deposit of material. CM,2Ting chain as specified in claim 1 wherein said conveying is at a rate greater than the loose volume rate of mineral production by said movement of said chain sections in a bedded deposit of mineral.

3. A cutting chain as specified in claim 1 wherein each of said chain sections connects two of said pins at a plurality of points spaced longitudinally of said pins and each of said pins extends the full width of said chain.

4. A cutting chain as specified in claim 1 wherein each of said chain sections has a plurality of conveying means spaced along said hinge pins to form said material receiving portions.

10. In an endless cutting chain as specified in claim 7 wherein said volume has a conveying rate greater than the loose volume of mined mineral produced by said orbital movement of said links in a bedded deposit of mineral.