US3700285A

US3700285A - Cutter chain support means

Info

Publication number: US3700285A
Application number: US140500A
Authority: US
Inventors: Lester G Rollins
Original assignee: Individual
Current assignee: Joy Manufacturing Co; Citibank NA; Joy Technologies Inc
Priority date: 1971-05-05
Filing date: 1971-05-05
Publication date: 1972-10-24
Anticipated expiration: 1989-10-24

Abstract

A cutter chain support means and more particularly a mining apparatus supporting a cutter chain for dislodging mineral from a solid mined vein.

Description

United States Patent Rollins Oct. 24, 1972 CUTTER CHAIN SUPPORT MEANS [56] References Cited Inventor: Lester G. Rollins, FOI'BSt Lane, P

Franklin, Pa. 16323 2 6 2 l 3 299/83 50,81 9 195 Joy [22] F11: May 1971 2,676,005 4/1954 16 ..299/83 [21] App]. N07: 140,500 3,305,273 2/ 1967 Kilboume ..299/76 X Related Application Data Primary Examiner-Ernest R. Purser [62] Division Of Ser. NO. 786,649, Dec. '24, 1968, Attorney-Eqwallace Brelsch abandoned.

[57] ABSTRACT [52] us. Cl ..299/s3, 299/67 A cutter chm-n Support means and more particularly a {51 1 1 c1 ..E21c 27/24 mining apparatus Supporting a cutter chain for [58] Field of Search ..74/243 247; dislodging mineral from a solid mined vein 7 6 11 Claims, 6 Drawing Figures 90 .95 75 //0 a4 99 m /00 92 /08 I06 I 0 6 Patented Oct. 24, 1972 2 Sheets-Sheet 1 CUTTER CHAIN SUPPORT MEANS This application is a division of application Ser. No. 786,649 filed Dec. 24, 1968 now abandoned and is filed pursuant to an examiners requirement for restric-.

cludes 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 example: an improved cutter chain drive sprocket structure for superior supporting of the cutter chain.

This 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 of a mining machine embodying the principles of this invention;

FIG. 2 is an enlarged view, partly in section, taken on line 22 of FIG. 1 and showing a portion of the cutter head assembly; I

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

FIG. 4 is an enlarged view, partly in section, taken on line 44of FIG. 3;

FIG. 5 is a fragmentary plan view of a portion of the drive sprocket of this invention taken substantially from lineS-S of FIG. 3;

FIG. 6 is a fragmentary sectional view of the portion of the cutter chain supports partly illustrated in FIG. 2, on a larger scale;

' 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 pivotably 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 thereof. Pivotably 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 jacks have one end thereof secured to the forward end of frame 16 and have the other end thereof secured to respective rearward lever ends of boom 18 and loading head 26. Motors 36, which are suitably rigidly secured by suitable brackets 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 Ser. No. 786,650, filed Dec. 3, 1968, andassigned 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 (see FIG. 2) 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 thecutter 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.

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 centerline of machine 10. Seats 108 extend under a portion of the outer edges of the links of the endless circulating cutter chain 76 (see FIG. 6) 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 rotational speeds of the cutter chain 76 and the seats 108 are equal and therefore there is no sliding 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.

A sprocket providing the cutter chain central support areas constructed according to the principles of this invention is shown in FIGS. 3 through 6 and comprises the cutter chain drive sprocket 82 having spaced arcuate shoulders 109 thereon at the flanks of teeth 84. There are no shoulders 109 at the tooth roots 110 and the shoulders 109 are so dimensioned that the diameters of the shoulder circles of the sprocket 82 are substantially greater than the diameter of the tooth root circle of sprocket 82.

The cutter chain drive sprocket 82 is dimensioned to provide arcuate shoulder surfaces 1 11 thereof which lie in approximately the same cylindrical surface as the contact surfaces of the spaced seats 108. With such surfaces 111 (see FIGS. 3 and 4) each link in the bight portion of chain 76 is supported at four areas, namely;

two end supports at the contact surfaces of the spaced seats 108; and two central supports at the shoulder surfaces 1 11 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, two or three 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 desirable for the construction of a chain wide enough for the purposes 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. A similar chain supporting arrangement but providing three point support is fully illustrated and shown in the hereinbefore mentioned U.S. application Ser. No. 786,650.

Well known screw type conveyor scrolls 118 are secured to the outer periphery of rotary drum cutting heads 78 and to well known scroll portion supporting sheaths 115 which are secured to the outer end portions of the rotary drum cutting head extensions 80 which are not receivable within cutting head 78 to support scroll portions 119 movable with the extensions 80. Such sheaths 115 allow the extension and retraction of head extensions 80 with scroll portions 119 thereon while still maintaining substantially continuous conveying surfaces with respect to the scrolls 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. 2 and 6 the cutter chain 76 comprises a plurality of links 90 which are hingedly connected together. Each link 90 comprises an elongated plate or body portion 92 having a plurality of elongated partially cylindrical hinge portions 91 axially spaced along the sides thereof. The hinge portions 91 of links 90 are formed integrally with the body portion 92 or rigidly secured thereto as by welding or the like. The hinge portions 91 form hinge notches 93 therebetween and in a well known manner are interfltted with hinge portions 91 of an adjacent link 90 and pivotally secured in such relationship by an elongated hinge pin (not shown). For further description of such a chain see U.S. application Ser. No. 786,649 of which this application is a division.

A centrally located drive sprocket opening 96 is provided in each body portion 92 through which a tooth 84 of cutter chain drive sprocket 82 extends to drive the cutter chain 76. Openings 96 may be of any suitable configuration which will permit suitable tooth engagement to drive chain 76. As shown opening 96 is a generally square opening symmetrically located with respect to the centerline of machine 10. The distance between centerlines of links sometimes referred to as the pitch length of the chain 76 is substantially equal to 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. 2) secured thereto in any suitable manner, for example welding around the peripheral edges of a bit holder 120 to join such holder to body portion 92. A cutter bit 122 is to be 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 10 and as such there is no requisite that each and every link 90 have a bit holder 120 thereon.

Cutter chain 76 additionally includes a plurality of conveyor flights generally indicated at 98 (only one of which is shown in FIG. 2) which extend transversely of cutter chain 76 between adjacent links 90. Flights 98 are formed from a plurality of aligned

lug portions

99 and 100 which project upwardly (in FIG. 6) from the working surface of chain 76.

Such lug portions are formed integrally with hinge portions 91 or are rigidly secured thereto as by welding or the like and include; lugs 99 which extend along substantially the entire length of a central hinge portion and project upwardly from the side of such hinge portions and lugs 100 which extend along substantially the entire length of short hinge portions 91 and project upwardly therefrom, as seen in FIG. 6.

Upon assembly of adjacent links 90 in a manner hereinbefore described,

lug portions

99 and 100 form conveyor flights 98 which are in spaced relationship to one another to deflne conveying pockets in cutter chain 76 between adjacent flights 98.

Referring particularly to FIG. 6 wherein there is shown a single link 90 in the condition to be found in those links 90 when making up part of the bight portion of the chain 76 at the forward end of the machine 10 in substantial alignment with the forward periphery of the cutter supporting scrolls 118 of the rotary head 78. It is to be seen that the bottom surface of each link body portion 92 is supported when in the bight portion of the chain 76 by left and right hand chain supporting seats 108 (as seen in FIG. 6) and in its central portion on both sides of the sprocket opening 96 is supported by the arcuate shoulder surfaces 111 of the sprocket 82. For this support function it is desired that the diameter of the seat 108 and the diameter of the shoulders 111 be substantially equal and that such surfaces be coaxial with each other. It is however not necessary that these values be exactly the same since. the purpose of the four-point support of this invention will be served by substantial alignment of the four surfaces at least within the limits imposed by the amount of bending the links 90 can undergo without exceeding the yield point of the material of the links 90.

it is to be realized that one of the advantages of the four-point support design resides in the relative ease of machining the arcuate surfaces 111 to the desired accuracy rather than having to form the root surfaces 110 between the teeth to that same accuracy to provide the proper support of the links 90. Another advantage of the four-point support design of this invention resides in avoiding the imposition of support stress along the central line of the links 90 where the material is approximately half cut away by the presence of the sprocket openings 96. Thus, the location at which support stress is applied, determined by the presence of the arcuate surfaces 111 is, in the structure according to this invention, shown to be the solid portion of .the link where the strength is much greater than in the half cut away central portion.

To mine mineral from a mineral face, the operator of machine 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 (i.e., the transverse shelf area which exists between the old forward face and the newly partially formed mined forward face, upon which shelf 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 demand and slower cutting rate and, additionally, an inordinate amount of undesirable mineral fines is produced.

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 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:

1. A cutter head for a mining machine consisting of a pair of axially elongated cutter carrying coaxial drum elements mounted on a common head shaft in axially spaced relationship; a single cutter chain drive sprocket drivingly mounted centrally of said shaft intermediate said drum elements, said sprocket being adapted to drive a cutter chain; said drive sprocket having tooth portions thereon separated by root surfaces therebetween; adjacent end portions of said drum elements having arcuate chain support contact surfaces thereon; and said sprocket having arcuate shoulder surfaces on each flank of each tooth with said shoulder surfaces lying in approximately the same cylindrical surface as said contact surfaces on said drum elements to provide laterally spaced four point support for such a chain.

2. A cutter assembly for a mining machine comprising the cutter head specified in claim 1 combined with an endless orbitable cutter chain supported on said four point support and having a chain width to pitch ratio of at least 4 to 1.

3. The cutter assembly as specified in claim 2 wherein said cutter chain is formed of hingedly connected links and each link in turn is simultaneously supported at said laterally spaced four points through a portion of the orbit of said chains.

4. A cutter assembly as specified in claim 2 additionally comprising an idler sprocket rotatable on an axis laterally spaced from and parallel to the axis of rotation of said drive sprocket, said chain being trained about both of said sprockets in a substantially elliptical shape.

5. The cutter assembly as specified in claim 4 wherein said cutter chain drive sprocket is powered to drive said cutter chain in a substantially elliptical orbit having respective bi'ght shaped end portions about said sprocket and each link of said chain supported at said four points simultaneously through at least a major portion of one of said bight portions of said orbit.

6. The cutter assembly as specified in claim 3 wherein each of said links comprises a plurality of hinge portions separated by a plurality of hinge notches therebetween with said hinge portions so located that the hinge portions of one of said links fit into the hinge notches of the adjacent ones of said links between the hinge portions thereof.

7. The cutter assembly as specified in claim 6 wherein said hinge portions of said adjacent links are pivotally connected together by a single hinge pin extending through the interfitted hinge portions between each pair of said links across substantially the full width of said chain. V

8. A mining machine cutter chain comprising; a plurality of hingedly connected links, each of said links being elongated laterally from the longitudinal centerline of said chain and having a chain width to pitch length ratio of at least four to one, each link comprising a body portion having a centrally located generally square drive sprocket opening therethrough, each link has four relatively aligned substantially coplanar areas upon the undersurface thereof, two of said areas being end portions of the body undersurface and the other two of said areas being body undersurface portions laterally adjacent said drive sprocket opening with respect to said longitudinal centerline.

9. A mining machine cutter chain as specified in claim 8 in combination with a cutter head assembly additionally comprising; an elongated support member; an elongated mining head member mounted at the forward end of said support member for powered rotation about the central longitudinal axis of said head member; axially spaced portions of said head member being cutter carrying rotary elements; said chain is a continuous hinge cutter chain movable in an orbital path extending transversely to said longitudinal axis, said orbit end portion being generally aligned with a forward peripheral portion of said rotary elements and the width of said chain extending between said rotary elements and said chain is trained about, supported and driven by a single sprocket located intermediate between said rotary elements and. having a plurality of teeth thereon, the improvement further comprising: said support means being four supporting areas for each of said chain links made up of adjacent end portions of said rotary elements and a shoulder area on each flank of the tooth of said sprocket engaged with the respective link undersurface portions while sai link is part of said orbit end portion.

. 10. A mining machine as specified in claim 9 wherein the shoulder circle is of substantially greater diameter than the diameter of the tooth root circle of said sprocket.

11. A mining machine cutter chain as specified in claim 8 additionally comprising bit blocks mounted upon a surface of said body portion of at least some of said links opposite said undersurface.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,700,285 Dated October 24, 1972 lnven fl Lester G. Rollins It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 1, line 7 (col. 5, line 53) cancel "drive"; (2nd occurrence) lines 8 and 9 (col. 5, line 54 and 55) cancel "separated by root surfaces therebetween line 12 (col. 5, line 58) after "tooth" insert portion line 15 (col. 5, line 61) before "laterally" insert four same line cancel "four point I same line after "support insert surfaces Claim 2, line 4 (col. 5, line 67) cancel "point same line after "support insert surfaces Claim 3, line 4- (col. 6, line 4) before "laterally" insert four same line cancel "four points and substitute support surfaces Claim 5, line 6 (col. 6, line 17) cancel "points" and substitute support surfaces Claim 8, line 1 (col. 6, line 32) after "comprising" insert a cutter chain having I line 10 (col. 6, line 41) cancel "body" and substitute link I line 11 (col. 6, line 42) cancel "body" and substitute link Y v Claim 9, line 18 (col. 6, line 63) cancel "being and substitute having I I Claim 10, line 2 (col. 7, line 2) cancel "circle is of" and substitute surfaces have a I Claim ll, line 4 (col. 7, line 8) cancel "said" and substitute the link Signed and sealed this 22nd day of May 1973.

(SEAL) Attestz EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM PC4050 uscoMM-oc sows-P69 A UCS. GOVERNMENT PRINTING OFFICE I 1959 0355'334

Claims

5. The cutter assembly as specified in claim 4 wherein said cutter chain drive sprocket is powered to drive said cutter chain in a substantially elliptical orbit having respective bight shaped end portions about said sprocket and each link of said chain supported at said four points simultaneously through at least a major portion of one of said bight portions of said orbit.

7. The cutter assembly as specified in claim 6 wherein said hinge portions of said adjacent links are pivotally connected together by a single hinge pin extending through the interfitted hinge portions between each pair of said links across substantially the full width of said chain.

9. A mining machine cutter chain as specified in claim 8 in combination with a cutter head assembly additionally comprising; an elongated support member; an elongated mining head member mounted at the forward end of said support member for powered rotation about the central longitudinal axis oF said head member; axially spaced portions of said head member being cutter carrying rotary elements; said chain is a continuous hinge cutter chain movable in an orbital path extending transversely to said longitudinal axis, said orbit end portion being generally aligned with a forward peripheral portion of said rotary elements and the width of said chain extending between said rotary elements and said chain is trained about, supported and driven by a single sprocket located intermediate between said rotary elements and having a plurality of teeth thereon, the improvement further comprising: said support means being four supporting areas for each of said chain links made up of adjacent end portions of said rotary elements and a shoulder area on each flank of the tooth of said sprocket engaged with the respective link undersurface portions while said link is part of said orbit end portion.

10. A mining machine as specified in claim 9 wherein the shoulder circle is of substantially greater diameter than the diameter of the tooth root circle of said sprocket.