US1303797A

US1303797A - Mining machine

Info

Publication number: US1303797A
Authority: US
Publication date: 1919-05-13
Anticipated expiration: 1936-05-13

Description

M. P. HOLMES.

MINING MACHINE.

APPucATIoN flLzo Aumal. 1914,

Patnd May 13, 1 919.

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M. P. HOLMES.

MINING MACHINE.

APPucATmN man wem. 1914.

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M. P. HOLMES.

MINING MACHINE.

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APPLICATION HLED AUG-31. |914,

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M. P. HOLMES. MINING MACHINE. APPucArlou mtu Ausm. 19u.

ww .r.,&.y ma e V2M. mm eamo mm mpx@ m Imm WR.. M MH, @fm .a m wwf/.2@ e a UNITED STATES PATENT OFFICE- MORRIS 1', HOLMES, 0F .CLABEMON T, NEW HAMPSHIRE, ASSIGNOB '.lO SULLIVAN MACHINERY COMPANY, F CLABEMONT, NEW HAMPSHIRE, A CORPORATION 0F MASSAGHUSETTS.

HIN'ING-MACHIN E.

Patented May 13, 191e.

` Contlnuationplnrpm of application Serial No. 833,782, tiled pril 22, 1914. This application tiled August 31,

`Be it known that I, Mouais PfHoLMEs, a.

fcitizen of the United States, and a resident of'Claremont, county of Sullivan, and State of 'NewHanipshirm have invented an Improvement in Mining-Machines, of which the followingdescri tion, in connection with the accoi'npaiiyiig l rawi'ngs. is aspecificatiom.

j" like' e'ha'i'ahfrs on they drawings representmme paas his invention relates to mining machines,

and moreV particularly, though not exclusively, to machines of the chain cutter type,

'and will be best understood by reference to the followiii specification, when taken in connection with the accompanyin drawings of one specific embodiment thereo while its scope will be more particularly pointed out inthe appended claims.

In the drawings: p

Figure 1 is a plan of one form of mining machine embodyingmyu. invention with the cover removed;

'-Fig.- 2 is aside elevation of the same;

' VFig. 3 is a sectional view on line 3-3 of "Fig-.1; ig. 3l 1s a central longitudinal section A- operating the cutter bars;

Fig. 5 is a detail, sectional view on an enlarged scale on line 5--5 of Fig. 1;

Fg. 6 is a detail, plan section on an enlaiged scale on line 6 6 of Fig. 2;

ig. 7 is a detail sectional view on line 7--7 of Fig. 4;

^ Fig. 8 is a detailelevation of ran enlarged scale on one of the friction clutches;

Fig. 9 is a detail plan of the parts shown in Fig. 8;

Fig. 10 is a, plan illustrating diagrammatically one mode of operation of the machine; and

Fig. 11 is a similar plan illustrating diaygrammatically another mode of operation of the machine.

Referring to the drawings, and to the eni-A bodiment of my invention which I have selected for illustration, I have there shown a mining machinecomprising,r a main portable support or bod) 12, the Yme herein 1914. Serial N0. 859,280.

comprising longitudinal supportin bars 13 and 14, the latter extending the fu l length of the machine and havingsecured to their upper faces fiat guide plates 15 and 16, on which a machine franie rests, and is adapted to slide, as will be described presenti The bed may be supported at its l orward end upon a suitable Vtruck frame 17,and atits rear end on a. similar truck frame 18, the former being journaled on

axles

19 and 20, provided .with wheels 21 and 2'2, while the rear-truck frame is journaled on axles 23 and 24, having secured thereto .

wheels

25 and 26. The wheels are adapted to travel upon rails of a suitable trackway 27, which will `be laid adjacentthe coal face or rib to be cut, either parallel with the same or at right angles thereto, or in any other desired .relation, as conditions may require.

The machine frame carrying theprincipal working pants, and which is adapted to have a longitudinal sliding movement along the bed, comprises a motor casing 28 at the rear end thereof, a housing 29 for the head hereinafter described which carries the cutting appliances, and an intermediate casing 30, the latter carrying the principal transmission gear parts. These three casings are rigidly bolted together to form a continuous machine frame. and are rovided on their under faces each with guideways and suitable gib plates, which fit the guide plates 15 and 16, wherebv the entire machine frame is accurately guided as a unit to travel longitudinally of the bed.

The present type of machine` as thus far described, is, or may be, similar to that foriningr the subject mutter of my pending application for mining machines, `filed April 22nd, 1914, Serial No. 833,782, wherein the inaehine frame is adapted to he traversed under power bach and forth on the hed. while the cutting` appliances are beingr operated, and wherein t e hed itself may be traversed on its trucks longitudinally of the trackway, under the, power of the machine.

It is deemed unnecessarir herein to show, or to describe in detail, the mechanism for effecting the traversingr of the machine upon its bed, although the mechanism for propelling the truck or hed along the tincku'ay will he hereinafter further referred to.

Referring now to the cutting appliances,

and the lsupport therefor, I have herein illustiated my invention as applied ,to a machine of the chain cutter type, .the saine being pro vided with a plurality of cutter bars, herein two, designated by the numerals 31 and 32, respectively, of common and usual construction, carrying cutter chains 33 and 3i, provided, respectively with cutter-

like bits

35 and 36. Preferably, the cuttei's of one set are arranged in staggered relation with the cutters of the other set, and extend toward the spaces therebetween. Preferably, also, the cutters of one set iii-c arr-.inged to actually enter into the spaces between the cutters of the other Set, So that -they actually overlap. The advantages securedz: by this ar rangement will presently appear.

In order to 'impart a cuttin movement to the chains, While maintaining the described relative arrangement, of the two sets of cutters, the cutter bars are so mounted and the chains so driven, that a definitely timed relation between the chains is insured, regardless of the Swingin motion of the cutter bars. To this end, t e cutter bars 31 and are provided respectively with hubs 37 and 38, swiveled in

bearings

39 and 40 in a vertically movable cuttencarrying head 41, the latter being provided with guides in the form of

tongues

42 and 43, mounted to slide` in

vertical guideways

44 and 4,5, respectively, in the cutter head housing 29. The cutter chain 33 is herein driven by a sprocket wheel 46, and the cutter chain 34 is driven by a sprocket wheel 47 in the customary and wellknown annex'. These sprocket Wheels are herein rmed on or secured to

sleeves

48 and 49, respectively, the lat-ter being coaxially arranged with respect to the hubs 37 and 38, constituting the pivots of the cutter lbars. Spur gears 50 and 5l, secured to the

sleeves

48 and 49, respectively, and of equal diameters, mesh with each other, and thereby cause the cutter chains to be driven in Unicom-that to say, in definitel y timed relation with each other, so tha-t as the cutter bars are swung to and fro, and :is they approacheach other, there shall be no interference between the two sets of cut ters, but ea'cli shall enter into the spaces between the cutters of the other set.

The sleeve 48 is herein driven by a shaft 52, and since the sleeve is carried vertically by the cuttencarrying head 41, it is necessary to provide a driving connection between the sleeve and shaft, permitting such movenient. To this end, the shaft may be rovided with one or more, herein three, eys 53, sliding freely in keyways 54 provided in the sleeve, thus providing a splined connection between the shaft and sleeve, whereby lthe latter may be raised or lowered, without disturbing the -driving connection, the shaft remaining in fixed position vertically.

The shaft 52 is herein diven by a beveled gear 55, secured thereto and meshing with a beveled pinion 56, both arranged within a fixed housing 57, which latter holds the beveled gear against vertical movement. The beveled pinion 56 is herein secured to a main driving shaft 58, journaled at its forward end in the housing 29 (Fig. 3) and at its rear end in the casing 30 (Fig. 3*). Y i To turn the shaft 58 and supply power for .the other movements of the machine, a driving motor 160 in the motor casing 28 is employed. The motor 160 `may be of any suitable type, but is herein shown as an electric motor having an armature shaft 161 carried in bearings supported by the oasin 28, there being secured to the armature sha t near its forward end a driving pinion 162 meshing with a large driving gear 163, the latter arranged concentric with the axis of the main driving shaft 58. The gear 163 is splined to a sliding clutch sleeve 164 freely rotatable on the shaft 58, the sleeve having clutch teeth onone side adapted to engage with similar clutch teeth on a member 165 fixed to the shaft 58. At its opposite end, the clutch sleeve 161 has similar clutch teeth adapted to be engaged with and drive a sleeved member 166 mounted for free rota.- tion upon the end of lthe shaft 58 and carrying a bevel driving ear 167. A clutch lever (not shown) ina utilized to move the clutch sleeve 164 ongitudinally. In one position, said clutch sleeve engages the driving member 165 and causes motoi driven movement of the shaft 58. If moved in the op- Y posite direction, it engages the truck driving sleeve 166 and drives the gear 167, while turning loosely about the shaft 58. In the intermediate Vposition shown in Fig. 3* both the shaft 58 and the gear 167 are disconnected from the driving motor 160.

The gear 167 is employed to propel the truck, and for that purpose engages a bevel gear 168, the latter mounted to turn with a shaft 169 in bearin carried by the frame of the truck or porta le support 12. A bevel pinion 1701s provided to turn with the gear 168 and meshes with a bevel drive gear 171, the latter mounted upon a horizontal shaft 172 which carries a bevel pinion 173 meshing with a bevel gear 174 secured to the rear axle 24. Sprocket driving chains 175 (Figs. l and 2) impart driving movement from the rear axle 24 tothe forward axle 23 on the rear truck. When the clutch sleeve 164 is moved to its rear position, the motor is utilized to pro el the truck through the mechanism descri ed.

As a i'neais for raising and lowering the cutter-carrying head, in order toei'iable the cutter chains to enter the vein at the desired height, the cutter head is provided with an elevating and depressing mechanism preferably comprising a luralit of elevating

screws

59, 60, 61 andJ 62. hreaded onto these elevating screws are nuts 63, 64, 65

`cal movement of t and 66, all of which are shown in Fig. 4, but only the nut 66 is shown in vertical sec tion in Fig. V3. As a means for causing all of the elevating screws and nuts to act in unison, they arclicrein geared together, the nuts having appropriately formed upon cr secured thereto spur gears 67, G8, 69 and 70, respectively.V The gears 67 and 68 mesh with a driving inion 71, while the ears 69 and 70 mesh with a driving pinion 2, said pinions being loosely mounted on the

sleeves

48 and 49 respectively.

As a means for supplying power to drive the pinions 71 and 72, the latter are provided with jaw clutches 73 and 71, which may be engaged with and disenga ed from similar clutches formed on the hu s of the ars 50 and 51, respectively. It will now gg evident that when the gears 50 and 51 are driven in the proper direction, they may be caused 4to drive the pinions 71 and 72, and thereby drive the

gears

67, 68, 69 and 70,

Awhereby the nuts 63, 64, 65 and 60, are

driven in the proper direction to raise or lower the cutter-carrying head 41, as the circumstances may require. It must be evident that to accomplish this, the elevating screws must be held fixed in the base of the cutter head housing 29, while the nuts must travel vertically with the movable cutter: head, the latter to that end being provided .with suitable housings to receive the driving gears, that for the gear 70 being indicated at 75. The nuts are journaled in ap propriate bearings, that for the nut 06 belng indicated at 76, said nut being held against axial movement in its bearing by a collar 77 at its lower end, and by the ear 70 at its upper end, whereby rotation o the nut on the elevatin screw enforces a vertihe nut which causes the cutter-carrying head 41 -to move correspondingly.

As a means for engaging the driving pinions 71 and 72 with and disengaging them from the gears 50 and 51, respectively, said pinions are herein provided with annular ooves 78 and 79 to receive a gear-shifting yoke 80, the latter having a stem 81 having appropriately formed t ereon or secured thereto a rack 82, meshingl with a inion 83, by means of which the yo re may ie shifted vertically to the extent necessary to engage the jaw clutches with and discngage them from each other. The pinion 83 is secured to a shaft 84, mounted in bearings 85 appropriately formed on or secured to the vertica ly Ymovable cutter-carrying head 41, in order to' move therewith. The clutches may be shifted manually through the described connections by means of a grasping lever 86 secured to the shaft 84, and projecting up- Wardly through an opening 87 to a point where it may be readi y grasped by the operator.

. its clearly shown.

As a means for causing discontinuance of the raising or lowering of -the cutter-carrying head at a predetermined point 1n its travel, I have herein "provided means 'for automatically shiftingA the pinions 71A and 72 out of driving engagement with the. ears To this end, the shaft 84 is erein provided with oppositely-

extendingA arms

87 and 88, having jaws 89V and 90, (Fig. 7) respectively, to receive

pins

91 and 92 carried b collars 93 and' 94, respectively, the latter' ing mounted to slide vertically on

rods

95 and 96. `These rods terminate at their' lower ends, and are iixedly secured to the base of the fixed housing 29. Secured to the -rod 95 at an appropriatepoint thereon is a sto collar 97, adapted to be engaged by the sli ing collar 93 at a suitable 'point in theupward travel ofthe cutter carrying head 41, whereby the driving pnonsare shifted to discontinue the upward movement.

of the head, while in a simllar manner, there is secured to the rod 96 at an appropriate point thereon a stop collar 98, ada ted tobe engaged by the sliding collar 94 uring'the downward travel of the head, to cause a discontinuance of the downward movement of the head.

rIt will now be evident that the mechanism just described prevents accidental over,- travel of the head in either its upwardor downward movement. j

I will now desc1ibe`the mechanism` by means of which the cutter bars or either of their. may swivel to and fro.'

Secured to, and depending ffrom., the cutter bars are

internal gear segments

99 and 100, the latter meshin respectively with pinions 101 and 102. he'sepinions are secured to

shafts

103 and 104, respectively, the' latter being journals/d in

appropriate bearings

105 and 106, carried by the vertically movable cutter head 41. In Fig. 5, the bearing 106`is shown in vertical section, and its mode of support onthe cutter head Since the cutter head carries the

shafts

103 and 104 verticali ,it is necessary to provide some means for riving said shafts, while permitting such vertica movement. vIt will be unnecessary to describe b`oth sets of driving connections for these shafts, since they are substantially identical, and I shall therefore describe only the driving connections for the shaft 104. The latter is herein provided with one or more, herein three, keys 107, arranged to slide freely in correspondingkeyways in the sleeve 108, (Fig. 6) vthe latter being'journaled, but held against axial movement, in

iso

use of a-clutch member 113, adapted to slide axially thereon, but held against rotation with relation thereto by one or more, herein three, keys 114 on the sleeve, en aging corresponding keyways in the sli ing clutch member. The latter is provided with jaw clutch teeth 115 adapted to interengage with clutch teeth 116 on the ear 110, and is also provided with jaw clutc teeth 117, adapted to be engaged withy clutch teeth 118 on the gear 111. It 'will now be evident that by shifting the clutch member 113 into driving connection with one of the beveled gears, the shaft 103 may be mtated in one direction, While if the clutch member be shifted into engagement with the other gear, the shaft will be rotated in the opposite direction. As a means' for shifting the clutch member, the latter is herein provided with a circumferential groove 119, to receive a clutch-shifting yoke 120. This yoke is herein secured to a rockshaft 121, extending entirely across the housing 29, and through

appro riate bearings

122 and 123 at opposite si es of the latter. Hand levers 124 and 125, secured to opposite ends respectively of the shaft 121 may be utilized to rock the latter, thereby to shift the clutches. In order that either clutch may be shifted independently of the other, the clutch shifting yokes are loosely mounted on the rockshaft121,bnt may be cou led thereto by the use of a mannally shiftab e clutch. These clntchcsarc identical in construction, and therefore a de scription of that used in connection with thyoke 120 will suffice for both.

Referring now to Fig. 6, the hub of the yoke 120 is rovided with clutch teeth 126 adapted to )e engaged by corresponding clutch teeth 127, formed on n sliding collar 128, the latter being keyed to the rockshaft 21 by means of a key 129. As a means for shifting the collar 128, the same is herein provided with 'Y an annular groove 130, to receive a forked lever 131 having a grasping portion 132 projecting through the wall of the housing 29 to the exterior thereof, where it may be grasped by the hand of the opera- 'tor. It will now be apparent that by the use of the described clutches, either'of the cutter bars may be swung independently of the other, or both bars may be swung simultaneously in either direction.

The pinion 112 (see Fig. 5), is herein secured to a shaft 133, the latter being journaled in

bearings

134 and 135, and having secured thereto a worm gear 136 meshing with a worm 137. It should be remembered here that the mechanism just described is duplicated at the other side of the machine, and that therefore there is another worm similar in function to the worm 137 ust referred to. Both of these worms are secured to a shaft 138, the latter having also secured thereto u worm gear 139 meshing with a worm 140.

This worm is loosely mounted on a power shaft 58, but. may bc driven lhcreby through the use of appropriate connectingr devices, for example a friction clutch Hl herein comprising a clutch member 142 formcd on the hub o the worm 140. and n mating clutch member 113, the latter boing slidable axially on the shaft, but. keyed to rotate therewith by the se of the key 144.

As a means for causing driving engage ment of thcs(` clutch members with each other, there is herein provided a helical compression spring H5, encircling the shaft 58, disposed in a rcccss 140, and bearing at one end against thc inner end ot' said recess and at, the othcr cud against an adjustable abutment 147, appropriately secured to the shaft as by a screw thlread. This clutch provides a friclional driving connection ca.- pnblc of slipping when the swinging cutter )ars reach the limit of their travel in either direction. This driving connection may be manually intcrruptcd at will through the use of a clutch shifting lcvcr 14S, engaging n collar 149 located in n ammini' groove 150 in the shiftable clutch member 143.

The described form ot' machine may be used for a great variety of purposes, but thc specific en'ibcdiment herein shown has particular application to the cutting of kcrfs nt variable heights between the door and the roof of the mine. This is often required where a dirt seam extends across the face or rib of the coal near the roof, or intermediate the roof and the lioor, and it becomes necessary to cut out or remove this seam before the coal is broken down, or where for any other reason the kerf is requircd between the fioor and the roof.

The machine may be utilized for rib cut.- ting by laying the trackivay parallel with and closely adjacent the rib on either side of the machine, and the iropcr cutter bar may be swung laterally irom the position shown in Fig. 1 into thc face of the rib, until the cutter bar stands at right angles to the longitudinal dimension ot' the :nachine. whereupon the machine frame is moved longitudinally to cause the cut-ter bar to be fed in a path parallel with the face of the rib.

During this cutting operation, the bcd and trucks are held fixed by any suitable clamping means, such as a jack post similar lo the jack post 151 represented in Fig. 2.

lVhile the machine is capable of use for rib-cutting as just described, it has particular advantages in connection with entry cutting, and in Figs. 10 and 11. l have illustratcd .its application to this class of work, Fig. 10 showing one method of operation and Fig. 11 another. Herein, the trackway is laid upon the bottom of the mine near the mid-portion of the entr and the machine is brought up on the trac way with the forward end of bed close to the face of the coal. Vith the two cutter bars projecting forwardly parallel to each other-'and paral el to thelongitudinal median lineof the machine, the frame lmay be fed to the forward I imit of its movement upon the bed, then-clamped in position, after which power is supplied to swing thccutter bars laterally in opposite directions to `the proper extent, whereupon their outward movement is stop ed, and the machine bed retracted, until tie cutter bars are entilely'withdrawn from the work. The different successive positions-bccupied by the cutter bars during the foregoing operation are marked respectively A-A, B-B, CPC and D-D in Fig. 10. Another method of operation is illustrated in Fig. l1, in which it will be observed that'the cutter bars 4are first swung laterally inopposite directions to the proper extent, they are then held fixed in such position, after which the machine frame is fed forward to the limit of its movement upon the bed; the machine is then clamped in position, after which the cutter bars are swungr inwardly toward each other, thus completing the cut, after which anew cut may be commenced by simply swinging the cutter bars outwardl and advancing them as bcfore. The dili'erent successive positions occupied by the cutter bars during the foregoing operation are indicated respectively by the letters E-E, F-F, and G-G in Fig. 11. The latter mode of operation is'prcferred to the former, 'because of the saving of time due to the elimina-tion of one of the movements required in the former.

The use of the duplicate arrangement of Y the cutter bars has certain other distinct advantages in entry cutting, among them being the rapidity of the cutting operation, and absence of lateral thrust, the latter being due to the fact that the thrust of one cutter bar equalizes that of the other. This makes ity possible to operate the machine without the use of ,any jacks to receive lateral thrust. The vertical adjustment ofthe cutting appliances can be performed without disturblng the position or relation of the other working parts of the machine, and the ver tical location of the hert in the face or in the rib may be changed quieklyand easily at, any time, as may be required to suit the particular conditions met.

lVhile. I have herein shown and described one specific fprm or embodiment of my invention for illustrative purposes, and have disclosed and discussed in detail the construction and arrangement incidental to one specific application thereof. it is to be understood that the invention' is limited, neither to the merc details or relative arrangement of parts, nor to its specific embodiment herein shown, but that extensive deviations from the illustrated form or embodiment of the invention may be made, without departin r from the principles thereof.

Illaving thus described my invention, what Iclaim and desire by Letters Patent to procure is:

1. In a mining machine, a support movabletoward and from the work, and a pair of cutting devices on said support and movable between a separated position and a. position of adjacent arallelism'in-which the cuts made there joined.

2. In a mining machine, a 'support movable toward and from the work, and a pair of swinging cutting devices movable thereon between a diver-ging position and a position of adjacent parallelism in which the cuts made thereby are substantially joined.

y are substantially"` 3. In a mining machine, a. pair of cutting devices, means whereby said cutting devices may be moved toward and from the Work, and means for moving said cutting devices between a separated positron and a position of adjacent parallelism in which the cuts made thereby are substantially joined.

4. In a mining machine, a pair of swingingr4 cutting devices, means whereb said cutting devices may be moved towar and from the work, and means for moving said cutting devices between a diverging position and a position of adjacent` parallelism in which the cuts made ythereby are substantially joined.`

5. In a mining machine, a frame, a. pair of cutter bars mov-ably mounted on Said frame, movable cutter chains on said bars,

means whereby said frame may be moved toward and from the work, and means for moving said cutters bars between a separated osition and a position of adjacent paralliilism in which the cuts made thereby are substantially joined.

G. In' a mining-machine, a frame, a pair of swinging cutter bars pivoted thereon, movable cutter chains on said bars, means whereby said frame may be moved toward and from the work, and means for moving said cutter' bars between a diverging position and a position of adjacent parallelism in which the cuts made thereby are substantially joined.

7. In a mining machine, a pair of cutting devices, means for operating said cutting devices, means whereby said cutting devices may be moved toward and from the work while in ojwration, means for moving said 8. In a mining machine, a truck provided with ways, a vframe movable on said ways, a pair of cuttin devices on said frame, means for operating said cutting devices, and means for moving said cutting devices on said frame between a separated position and a iosition of adjacent parallelism in which t e cuts made thereby are substantially joined while continuing their operation.

9. In a. minin machine, a support movable toward an from the work, a second support movable on said first named support in a direction longitudinal to the movement thereof, and a pair of cutting devices on said second suplliort and movable thereon between a separate jacent parallelism in which the cuts made thereb are substantiall joined.

10. n a mining machine, the combination of a pair of cutting devices each provided with a set of spaced cutters, the cutters of one set being arranged to enter into the spaces between the cutters of the other set; means for moving said cutting devices one toward and from the other; and means for imparting a cutting movement to said devices while insuring the continuance. of the relative arrangement of the cutters of the two sets so that the cutters of one set shall enter into the spaces between the cutters of the other set when said devices are movedone toward the other.

11. In a mining machine, the combination of a pair of cutter bars; a pair `of cutter chains carried thereby and provided each with a set of spaced cutters, thcpcutters of one set being arranged to enter into the spaces between the cutters of the other set; means for moving said cutter bars one toward and from the other; and means for driving said cutter chainswhile insuringr a definitely timed relatiolitherebetween so that the cutters of one set shall' enter into the spaces between the cutters of the other set when said bars are moved' one toward the other.

12. In a miningr machine, the combination of a pair of cutter bars, movable toward and away from one another, a pair of cutter chains carried thereby and provided each with a set of spaced cutters, the cutters of one set being arranged in staggered relation with the cutters of the other set and extending toward the spaces therebetween; and means for drivingr said cutter chains while maintaining a definitely timed relation therebetween so that the cutters of one set shall be opposite the spaces between the lcutters of the other set when said cutter bars are moved one toward the other.

13, In a mining machine, a frame, a pair of swinging cutter bars pivoted thereon immediately adjacent to one another and movable. 'nto parallel relation, cutter chains on Vsaid bars having cutter bits brid'ging the position and a position of adgap between said bars when the same are in parallel relation, means for swinging said bars from diverging to parallel relation, and means for operating said cutter chains.

14. A mining machine comprising, in

tively, a single motor, and means for driving said cutter chains and swinging means from said motor.

15. A mining machine comprising, in combination, two pivoted cutter frames each provided with a cutter chain, and means for swinging said frames contemporaneously in opposite directions respectively and simultaneously operating said chains including a motor operatively connected both to one of said' frames and its chain. 85

1G. A mining machine comprising, in combination, two cutter frames each provided with its cutter chain, swinging means for swinging said cutter frames contemporaneously in opposite directions, a single motor, means for driving said cutter chains and swinging means therefroin, and disconnecting means for operatively -disconnecting one of said cutter frames from said motor.

17. In a mining machine, a truck, a plurality of pivotd cutter bars thereon, endless cutter chains carried on said bars, means for swinging said bars from diverging'relation in opposite directions toward one another, means for operating said chains, truck driving means, a single motor, and driving means operatively connected between each of said several means and said motor.

18. In a mining machine, a pair of cutting devices, means for operating said cutting devices, means whereby said cutting devices may be moved toward and from the work while in operation, means for bodily moving said cutting devicesl in opposite directions respectively and iu va direction transverse to their first named movement while continuing their operation` a motor, and connections between said motor and said cutter operating means and moving means for actuating both of said means.

19. In a mining machine, a pair of swinging cuttingdeviees. means for operating said cutting devices, means whereby said cutting devices m'ay be moved toward and from the work while in foperation, means for swinging said cutting devices toward and from each other while continuing their operation, a motor, and connections between said motor and said cutter operatin means and swinging means for actuating th of said means.

20. In a minin machine, a pair of pivoted cutterA bars, end ess chains on said cutter bars each provided with a set of cutter bits,-`

means for driving said chains in timed relation, means whereby said cutter bars may be moved toward and from the work while said chains are in operation, means for swinging said cutterbars on their pivots between 'a diverging position and a position of parallelism with the cutter bits of one set entering the spaces between the cutter bits ot' the other set while continuingthe operation of said chains, a motor, and driving connections between said motor and said chain driving and bar swinging means for actuating both of said means.

21'. In a mining machine, a truck irovided with ways, a frame movable on sait ways, a pair of cutting devices on said frame, means for operating said cutting devices, means for moving said cutting devices on said frame in opposite directionsl respectively while continuing their operation, and a singie motor and connections for actuating said cutter operating and moving means.

22. In a 4mining machine, a vertically movable support, means for raising and lowering it, a pair of cutting devices on said support, means for operating said cutting devices, means whereby said cutting devices vmay be moved toward and from the work while in operation, means for moving said cutting devices in opposite directions respectively and in a direction transverse to their 'pair of cutting devices on said frame, means for operating said cutting devices, and means ioi moving said cutting devices on said frana` in opposite directions, respcctivelyvwhile-continuing their operation.

24. in a mining machine, truck provided with ways, a frame horizontally movable. on

said ways, a support vertically movable on said frame, incaus for raising and lowering said support, a pair ot' `cutting devices on said support, means for operating said cutting devices, and means for moving said cutF ting devices on said support in opposite directions, respectively, while continuing their operation.

in testimony whereof 1 have signed my name to this speciiication in the presence of two subscribing witnesses.

MORRIS l. HOLMES. "itiiesscs 1l. C. Usooooy Tiinooonn B, JoiiaNNis.