US2359422A

US2359422A - Mechanism for removing cuttings from the kerf cutter of mining machines

Info

Publication number: US2359422A
Application number: US468398A
Authority: US
Inventors: Florence H C Jeffrey
Original assignee: Jeffrey Manufacturing Co
Current assignee: Jeffrey Manufacturing Co
Priority date: 1942-12-09
Filing date: 1942-12-09
Publication date: 1944-10-03
Anticipated expiration: 1961-10-03

Description

1944- -R. K. JEFFREY MECHANISM FOR REMOVING CUTTINGS FROM THE KERF CUTTER OF MINING MACHINES Filed Dec. 9, 1942 4 Sheets-Sheet 1 In a 5 O .7

a Q Q 2 E5 0 5| JA/V/EA/TOEL' ROBEQT K. JEFFREY, DECf/JSED.

BY FLOQENQE HQJEFFEEN:

inseam/x.

Oct, 3, 1944. -R. K. JEFFREY MECHANISM FOR REMOVING CUTTINGS FROM THE Filed Dec. 9, 1942 KERF CUTTER OF MINING MACHINES i/lll Y x .,=L..,X I 923 w m m A TEEFW NJEEE. V

m. w H

0 Y H B Y 8 -R. K. JEFFREY 2,359,422

MECHANISM FOR REMOVING CUTTINGS FROM THE KERF CUTTER OF MINING MACHINES Filed Dec. 9. 1942 4 Sheets-Sheet 4 Oct. 3, 1944.

f/VVf/VTOQ, BERT KJEFFREY, DECEASED, BY FLORENCE H.C.JEFF2EY.

ExEcum/x.

q ATT'Y Patented Oct. 3, 1944 MECHANISM FOR REMOVING CUTTINGS FROM THE KERF CUTTER. OF MINING MACHINES Robert K. Jeffrey, deceased, late of Bexley, Ohio, by Florence H. C. Jeifrey, executrix, Bexley, Ohio, as'signor to The Jeffrey Manufacturing Company, a corporation of Ohio Application December 9, 1942, Serial No. 468,398

16 Claims. (Cl. 262-30) invention is the provision of improved and eflicient means for removal of the cuttings away from the kerf cutter and depositing the cuttings away from the feeding path of travel of the mining machine.

Another object of the invention is the provision of a rotatable abutment drum having flights rotatable therewith and adapted to reciprocate in planes extendingthrough the drum axis of rotation in positions where the projected and retracted flights will be efiective to sweep cuttings from the kerf cutter of a mining machine and deposit them where they will not be moved back toward the kerf cutter.

A further object of the invention is the provision of an improved and eilicient slip clutch in combination with flight means for removing cuttings from the kerf cutter of a mining machine.

Another object of the invention is to provide a deflector adjacent the kerf cutter of a mining machine to direct cuttings therefrom to cuttings removal mechanism connected to and movable bodily with the mining machine as it is being fed along a coal face.

A further object of the invention is the provision of a closed guard plate on the advancing side of cuttings removal mechanism connected to a kerf cutter mining machine to deflect any piled up material from being received by the supporting frame of the removal mechanism and to prevent cuttings from being thrown out from said advancing side or confining the ejection of the cuttings from the trailing side of the cuttingsremoval mechanism.

More particularly it is the object of the present invention to provide in cuttings removal mechanism associated with the kerf cutter of a mining machine, a. stationary cam in position to be engaged by flights to slide the latter along guides in the periphery of a rotary drum to effect reciprocation of such flights in planes extending through the axis of rotation of said drum, to secure maximum eiiective working area of each end of each flight when adjacent the kerf cutter and zero working area when remote from the kerf cutter, thereby enabling the flights to move the cuttings away from the kerf cutter and deposit the cuttings where they will not be moved back toward the kerf cutter.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings,

Fig. 1 is a side elevation of a shortwall mining machine with improvements embodied therein for removal of the cuttings produced thereby;

Fig. 2 is a rear end elevation of the structure shown in Fig. 1;

Fig. 3 is a plan view of the mining machine shown in Fig. 1;

Fig. 4 is a sectional plan view of the cuttings removal mechanism associated with the chain kerf cutter of the mining machine;

Fig. 5 is an enlarged sectional elevation taken transversely of the advancing portion of the mining machine shown in Fig. 3, Fig. 5 showing the mechanism for operating the rope feeding drum on the advancing side of the machine;

Fig. 6 is an enlarged sectional elevation taken longitudinally of the. central left-hand portion of Fig. 3 to show the mechanism for driving the cutting and removal mechanism from the kerf cutter operating mechanism of the mining machine;

Fig. '7 is a perspective view of the flights of the cuttings removal mechanism and their relation to other parts, part of the operating drum being broken away to show the flight reciprocating cam more clearly;

Fig. 8 is a perspective view of the guard plate mechanism; and

Fig. 9 is a perspective view of one of the dehector plates welded to the mining machine frame as shown in Fig. 4.

' Referring to the accompanying drawings, it should be noted that the cuttings removal mechanism is a unit ill which is adapted to be detachably connected by means of cap screws II to the main frame i i of the mining machine which includes the chain kerf cutter I2. 'In Fig. 5 the supporting frame of the cuttings removal mechanism is designated I0 and this frame may be welded to the extension it which is adapted to fit against the bottom plate I I, being held there by the cap screw it extending through the depending bracket l5 and threaded into the extension l3. The frame In may be thus detachably secured to the plate II at a plurality of spacedapart points.

The cutter bar I 6 is provided with the conventional endless cutter chain ll provided with picks or bits i8, which cutter chain I1 is driven from an electric motor carried by the main frame ll of the mining machin under the cover plate I9 shown in Fig. 3. As indicated in this view, the armature shaft of the electric motor is connected to the pinion which meshes with the gear 2| secured to a shaft carrying the worm 22. This worm 22 meshes with a worm gear 23 which, as shown in Fig. 5, is mounted on the roller bearing 24 concentric with the vertical shaft 25 to the upper end of which is secured the clutch gear element 26.

Secured to the upper side of the worm gear 23 is a spur gear 21 which meshes with the vertically sliding clutch gear element 28; the latter has an annular groove 29 to which is connected the shipper 30. By means of the shipper 30 the clutch gear element 28 may be slid upwardly into mesh with the gear element 28 and when this occurs the worm gear 23 will be brought into driving relation with the vertical shaft 25, the lower end of which carries the sprocket 3| meshing with the cutter chain l'l.

As shown in Fig. 5, the vertical shaft 25 is journaled by means of the

roller thrust bearings

32 and 33 to the tubular support 34 which is secured to the frame ll of the mining machine by means of the

cap screws

35, 35. A retaining ring 36 is secured to the tubular support 84 by means of cap screws as shown in Fig. 5 to hold the

thrust bearings

32, 33 in adjusted positions.

The shaft 3! (Fig.5) which carries the worm 22 is connected to a hydraulic pump 38 (Fig. 3) for supplying hydraulic pressure to the hydraulic motors 39 and 40. The hydraulic motor 39 is connected to a shaft 4| carrying a worm 42 which meshes with a worm wheel 43 as shown in Fig. 5. The worm wheel 43 is keyed to a shaft 44 mounted in Journal bearings and secured to a pinion 45 which meshes with an inner annular gear 46 of a rope drum 41. Ina similar manner, the rope drum 48 on the opposite side of the machine, as shown in Fig. 3, is connected through worm gearing 49 to the hydraulic motor 46 for operation thereby. For normal feeding operation of the kerf cutter transversely of itself, a rope 50 is connected to and wound on the drum 41 to extend therefrom around the guide pulley 5| and the rope 52 is connected to and wound on the drum 48 to extend therefrom over the

direction pulleys

53, 54. The ends of the ropes are connected to anchorages in the mine and as rope 52 is wound up the other rope 66 is paid out, under control of the hydraulic motors 39 and 46. For haulage purposes when the mining machine is to be moved from place to place in the mine without effecting any feeding operation, the rope 65. Keyed to the upper portion of the shaft 65 is a quill shaft or sleeve 61, the lower end of which is provided with a circular or annular extension 68 having on the bottom thereof and near the periphery, a series of circularly arranged recesses 69 for receiving the

balls

16, 16. These

balls

10, 10 extend through a series of circularly arranged openings in the upper horizontal portion of the gear 64 and contact with the top of the ring H which is iournaled on the hub I2 of the gear 64, as shown in Fig. 6. The ring H is supported by means of the ball bearing 13 on the annular support 14 which extends upwardly from the annular member 15. By means of a series of circumferentially spaced cap screws 18, the annular member 15 is secured rigidly to the frame H of the mining machine.

The upper end of the shaft-65 has a reduced extension 11 journaled by means of the ball bearing 18 in the horizontal upper plate 19 of the mining machine frame. Lubricating means 88 may be provided at the upper end of the shaft extension 11.

Journaled on the shaft extension 11 and resting on the annular shoulder 8| is a ring shaped cap 82 for receiving the upper end of the spiral spring 83, the lower end of which rests in an annular recess on top of the member 68.

The lower end of the vertical shaft 65 is provided with a circular plate 84 which fits into the ring 85. Between the lower end of the shaft 85 at the top of the plate 84 and th supporting ring 15 is a ball bearing 86. A circular lubricant sealing ring 81 intervenes the upper central portion of the plate 84 and the ring 15.

The ring 85 has welded thereto at 88 a cylinder 89, the lower end of which is open and located closely adjacent the inner upper surface of the plate l6 forming a part of the supporting frame of the cuttings removing mechanism. By

59 may be extended around the direction pulleys 55 and 56 and its free end anchored in the mine distant from the machine. When the pulley 56 is not in use, its supporting arm 51 may be moved to the vertical position shown in Fig. 6 and held there by the pivoted latch 58.

Keyed to the vertical shaft 25 is a spur gear 59 as shown in Fig. 5. This spur gear 59 meshes with a larger spur gear 60 which is journaled on a vertical bearing 6| as shown in Fig. 6. The gear 60 in turn meshes with a gear 62 journaled on the bearing 63, and the gear 62 meshes with the gear 64 which is concentric with the vertical shaft 65. The

gears

59, 60, 62 and 64 are all preferably in the same horizontal plane as shown in Fig. 6.

The spur gear 84 is journaled loosely on the means of cap screws 90, 98 extending through the ring sections 9|, 9| and threaded into the circular plate 84, the ring is supported at the annular recess 92. Inother words, the inner annular recess in the ring 85 at 92 co-operates with the periphery of the ring 84 to form a groove for receiving the annular upwardly extending extensions from the ring sections IL-as shown in Figs. 6 and 7.

The cylinder 89 and the mechanism for supporting the same constitutes a drum closed at the top by the plate 84 which rotates therewith and closed at-its bottom by the relatively station ary plate It). The cylinder 89 is provided with four vertical slots spaced apart 90 from each other. Extending through these vertical slots are

flights

93 and 94. The flight 93 is provided with an elongated opening of sufllcient length to have extended therethrough the other flight 94 when held in a horizontal position. The flight 94 has a central portion 94 adapted to move freely back and forth through the opening 95 when the flight 94 is vertical. 8

Riveted to the bottom plate I 0', as shown in Fig. 6, is a cam 96 having the approximately elliptical shape shown in Fig. 4.

Each of the

flights

93 and 94 is provided with cut-away portions to provide inner opposing curved edges for engaging the periphery of the cam 96. The flight plate 93 is provided with the lower opposing curved engaging edges 91 and 98 for engaging opposite sides of the cam 96, as shown in Fig. 4. The flight 94 is provided with lower inner oppositely facing curved edges 99 bushing 66 which is secured to the vertical shaft 75 nd NW for engaging opposite faces of the cam 98. At the slots in the periphery of the cylinder 89 of the drum are located guiding plates IOI, IOI for one end portion of the flight 93, and guide plates I02, I02 for the other end portion of the flight 93. In a similar manner, guide plates I03, I03 are provided for one end portion of the flight 94, and plates I04, I04 for the other end portion of the flight 94. Each of the guide plates may be welded at their outer vertical edges to the edges of the vertical slots in the cylinder 89, and these guide plates may be wider at their upper ends than at their lower ends, as indicated in Fig. 6.

By referring to Fig. 4, it will be seen that the flights 93 and '84 are so associated with the cam 98 that when a flight rotates in a clockwise direction as indicated by the arrows in the broken line circle I08, the flight will be projected farther out from the cylinder 89 of the drum as such flight approaches closer to the kerf cutting chain cutter I2. The cuttings produced by the kerf cutter are swept by the bits I8 in the direction of the arrows on the broken line I08.

It should be particularly noted that as the cylinder 88 rotates, the curved edges 91, 98 always remain in contact with the periphery of the cam 98 and likewise the curved surfaces 99, I always remain in contact with the periphery of the cam 98. The distance between the cam points of contact will always be the distance between the curved edges of each flight, and a vertical plane through these points of contact of each flight always extends throughthe center of rotationof the cylinder 89. Considering the cam 98 as elliptical its foci are in fixed triangular relation to the center of rotation of the cylinder 89 and are offset from such center with each of the foci and said center of rotation stationary relative to the cam and relative to the plate III. However, the periphery of the cam 98 preferably varies from a true ellipse slightly to secure maintenance of contact of both curved surfaces 91,98 of the flight 93 and of both curved surfaces 99, I08 of the flight 94 with the cam 96 at all times during rotation of the cylinder 89.

Furthermore, the distance between the curved surfaces 91, 98 of the flight 93 equals the distance between the curved surfaces 99, I00 of the flight 94. As the curved surface of each flight rides along the cam surface away from the center of rotation of the cylinder 89, such curved surface acts as the advancing one while the other curved surface of that flight follows as the trailing curved surface. Each curved surface therefore alternates in advancing and trailing.

A vertical deflector plate I01 welded to the frame of the mining machine has the shape of a segment of a cylinder and extends from the bot-- tom plate III to a position close to the path of travel of the outer end of each of the flights. Consequently the flight is extended to a maximum extent when closest to the chain cutter. As each flight continues to rotate in a clockwise direction, it acts positively on the cuttings to sweep them rearwardly and off the bottom plate I0. At the same time each flight recedes into the drum as it approaches the abutment I08, the inner surface of which at I09, as shown in Fig. '7, has the shape of a segment of a cylinder concentric with the cylinder 89 or the axis of rotation of the drum. It will thus be seen that the periphery of the cylinder 89 may be located in close proximity to the inner surface I09 of the abutment I08. The height of the abutment I08 is approximately co-extensive with the height of each of the

flights

93 and 94. Consequently practically no cutting will be carried past the abutment I08 back toward the kerf cutter. Further- -more, the vertical edge IIO of the abutment I08 may be sufliciently sharp to scrape from the outer surface of the cylinder 89 such material as may be clinging thereto. Moreover, the flights may have a suflicient fit between the plates along which they slide that such material as may cling to the outer surfaces of the flights may be wiped off when the flights recede into the drum.

It should be particularly noted that when the kerf cutter is fed in a direction transversely of itself and toward the anchorage to which the' free end of the rope 52 is connected, the

flights

93, 94 will exert a positive action on the cuttings to move them out from the rear side of the cuttings removing mechanism and entirely away from where the mining machine rest on and slides over the mine bottom. The bottom plate I0 of the supporting frame for the cuttings removing mechanism is also in position to rest on and slide over the mine bottom as the kerf cutter i fed transversely of itself.

When the kerf cut is relatively wide so that considerable cuttings are produced, the flight extensions by their positive actions on the cuttings will push the newly produced cuttings into the accumulated pile of cuttings with substantially no production of dust in the air adjacent the mining machine or the cuttings removing a mechanism. However, this continual pushing action of the coal cuttings as soon as produced, into the accumulated pile of coal cuttings tends to cause the cuttings to accumulate in advance of the plate I0 and I have therefore provided an upright deflector plate III the lower edge of which may have attached thereto a clip II2 adapted to fit into an opening II3 near the outer edge of the plate I0. One end of the deflector plate I II may flt against the advancing end of the abutment I08, and the other end of the deflector plate II I may flt between clips H4, H4 at the rear end of the mining machine frame, as shown in Fig. 4.

When the feed of the mining machine is reversed from that indicated in Fig. 3 by rearrangement of therope 50 at the guide pulleys 53' and 54, and reversal of the cutter bits I8, the rotation of the drum and the flights may be correspondingly reversed and in that event the upright guard plate III is mounted on the other side of the machine, with one end between the clips H4, H4 and the other end against the other end of the abutment I08. In that event also the deflector I01 will be brought into play for directing the cutting from the kerf cutter into the sweeping paths of the

flights

93 and 94.

Reverting to the ball clutch mechanism shown in Fig. 6 it will be evident that if either

flight

93 or 94 should meet an obstruction which might cause part of the mechanism to break, the spring 83 will be compressed intermittently as the plate 68 travels over the balls I0, I0 and gives the signal by the noise produced that the operation of the machine should be discontinued and the obstruction removed.

It should be particularly noted that by reason of the

flights

93 and 94 being projected from diametrically opposite sides of the drum cylinder 89, the rapidity of the sweeping of the cuttings is suflicient to render the cuttings removing mechanism so efficient that during each half rotation of the drum the cuttings are removed and deposited where the tendency is reduced to a minimum for the coal cuttings to be moved back toward the kerf cutter. Thatis to say, instead of having each flight extend outwardly to a maximum extent once during each rotation of the I drum, it is extended out from thedrum to a maximum extent twice during each rotation of the drum. By referring to Fig. 4 it can be seen that while the right-hand end of the flight 93 is moving through 180", the other end is at the same time moving trough only 180 to reach its maximum projection from the drum. Thus the capacity for removing cuttings is increased twofold by having the opposite ends of each flight project from the drum and each acting to take the place of the other during each 180 of rotation of the drum cylinder 89.

The

flights

93 and 94 may rest by gravity partly on the upper surface of the plate l and partly on the upper surface of the cam plate 96 but it is preferred to space those portions of the

flights

93, 94 that overhang the cam 99 slightly from the upper surface of the plate 19' and have the flights rest by gravity on the upper surface of the cam 96 since the latter is always inside the cylinder 89 and therefore relatively free from cuttings or foreign material. The

flights

93 and 94 are therefore supported on the upper surface of the cam 99 and can slide freely thereon when rotated since such upper surface is much cleaner than the upper surface of the plate l0.

However, the lower edge of the cylinder is in close proximity to the plate l9 and the flights 98, 94 fit closely in the slots in the cylinder 89. The cylinder constitutes a cylindrical abutment, or the drum above referred to may be considered the rotating abutment, whereas the abutment I99 is stationary. However, should any dust accumulate within the cylinder 89, it may be eliminated by passage through the openings 5, H shown in Figs. 4 and '1.

It should be particularly noted that if the

flights

93, 94 become worn they may readily be renewed after detaching the plate Hi from the frame of the mining machine, by removing the plurality of cap screws one of which is shown at l4 in Fi 5.

Since the slots in which the

flights

93, 94 are slidable are open at their lower ends, these flights can readily be permitted to drop out from the drum cylinder 99 without removing the cap screws 99, 90,, When the flights have been removed they may be taken apart by rotating one 90 relatively to the other so that the flight 94 may be moved out of the opening 95. When assembling a new pair of flights they are flrst placed at right angles to each other and then moved upwardly into the slots in the cylinder 89 and the cam 96 replaced by securing the plate III to the mining machine frame. The flights are then again interlocked by the slots in the cylinder 99 and each flight may be reciprocated freely in its own plane without interference from the other, on account of the narrow portion 94' of flight 94 extending through the elongated or rectangular opening 95 in the flight 93.

Reverting to the ball clutch shown in Fig. 6, it should be noted that the downward thrust of the spring 93 is exerted through the clutch balls 19 and ball bearing 13 onto the ring 15 that is secured rigidly to the frame of the mining machine. The gear 64 is thus relieved of the thrust from the spring 83 and when the gear 64 rotates the ball clutch mechanism rotates therewith as a unit with the ball bearing 13 at the lower end of such unit and the ball bearing 18 at the upper end thereof.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended, and it is therefore desired not to be restricted to the precise construction herein disclosd.

Having thus described and shown an embodiment; of the invention, which is desired to be secured by Letters Patent of the United States is:

1. In mining apparatus, the combination with a mining machine having a. kerf cutter, of a cuttings cleaner adjacent said kerf cutter comprising a horizontal ground engaging base plate, a rotating blade, a cylindrical member through which said blade projects, means for rotating said cylindrical member relatively to said base plate horizontally and thereby effect rotation of said blade to sweep cuttings along said base plate, and a. non-circular stationary device engaged by said blade to effect reciprocation thereof to successively project and retract the same relatively to said cylindrical member as the latter is rotated.

2. In mining apparatus, the combination with a mining machine having a chain kerf-cutter, of a support comprising a base plate connected to said mining machine, a rotary member mounted on said support to rotate relatively to said base plate on an upright axis, a flight mounted to rotate with said rotary member and to project from diametrically opposite sides thereof, means for rotating said rotary member to effect rotation of said flight, and flat cam mechanism on said base plate in position to be engaged by said flight during the rotation of said rotary member to effect reciprocation of said flight relatively to said rotary member to successively project the opposite ends of said flight from said rotary member, each end to a maximum extent when adjacent said kerf-cutter and then to recede as the flight sweeps the cuttings away from said kerf-cutter.

3. In mining apparatus, the combination with a motor driven mining machine adapted to rest on and slide over a mine bottom andincluding a chain kerf cutter, of a supporting frame having a horizontal bottom in sliding contact with such mine bottom, means connecting said supporting frame to the mining machine to slide over the mine bottom therewith, a drum mounted on said supporting frame to rotate relatively thereto on a vertical axis, a cuttings scraping device associated with said drum to rotate therewith and to reciprocate radially through said vertical axis, means operable from the motor of the mining machine to the top of the drum to secure rotation of the latter and rotation of said scraping device on said vertical axis, and a stationary device on said supporting frame stationary relative thereto in position to be engaged by said scraping device to effect scraping of the cuttings away from said mining machine by such radial reciprocation relatively to said drum when the latter is rotated.

4. In mining apparatus, the combination with a mining machine having a kerf cutter, of a supporting frame connected to said mining machine to move bodily therewith, a drum having an outer cylindrical surface and mounted on said frame to rotate relatively thereto on a vertical axis, an abutment mounted on said frame remote from said kerf cutter and in close proximity to said outer cylindrical surface of said drum, a plane flight extending entirely through said drum so that both ends may project from the drum at the same time and so that said flight may recipro cate relatively to'the drum, means for rotating said drum to rotate theflight, and means comprising a cam engaged by said flight intermediate the ends thereof for effecting such reciprocation of said flight that when one end is adjacent the kerf cutter projected to a maximum extent the other end is adjacent said abutment at the surface of the drum with zero projection.

5. A cuttings ,.cleaner for a kerf-cutting mining machine comprising the combination with a frame adapted to be detachably connected to such mining machine, of a rotatable drum having a plurality of vertical slots in its periphery with each slot open at its lower end, a plurality of flights insertable into said slots from below when said frame is detached as aforesaid, a cam,

fixed to said frame in position to be engaged by said flights when said frame is attached to the mining machine, and means for rotating said drum to effect reciprocation of each of said flights.

6. In mining apparatus, the combination with a mining machine having a chain kerf-cutter, of a cuttings removal unit comprising rotary flight means mounted on a supporting frame adapted to rest on and slide over the mine floor, an abutment in close proximity to said rotary flight means, an upright guard plate in advance of the said rotary flight means at' the leading edge of said supporting frame, the space back of said rotary flight means above the trailing edge of said frame being open for free and unobstructed mine floor back of said frame and rearwardly of said rotary flight means, and an upright curved deflector extending from the advancing side of vice, and means comprising a non-rotatable cam secured to said base plate and associated with the lower edge of said flight intermediate the ends of the latter to vary the'effective working area of the flight from a maximum to a minimum during each rotation of said device.

8. In mining apparatus, the combination with a mining machine having a chain kerf-cutter, of a supporting frame connected to said mining machine to move bodily therewith, an abutment mounted on said supporting frame for rotation relatively thereto, a plurality of blades associated with said rotary abutment for reciprocation relatively thereto in planes extending radially through the axis of rotation of said abutment, said blades each being adapted to have its op-' posite ends project from said abutment on diametrically opposite sides thereof, an approximately elliptical cam secured to said supporting frame, spaced-apart wiping faces on each flight in position to engage the periphery of said cam, and mechanism connecting said supporting frame to said mining machine in position for said blades to sweep the coal cuttings from the kerf-cutter by positive action.

9. In mining apparatus, the combination with passage of cuttings from said kerf-cutter to the a mining machine comprising a kerf-cutter, of a positive action cuttings remover adjacent said kerf-cutter, said cuttings remover comprising a rotary flight, a non-rotatable cam, wiping faces on said flight in position to engage the periphery of said non-rotatable cam, means on said flight for supporting the latter on said cam, means for effecting rotation of said flight while supported on said cam, and mechanism co-acting with the engagement of said wiping faces of said flight with the periphery of said cam to effect reciprocation of said flight and variation of the effective working area of the flight from a maximum to a minimum.

10. In mining apparatus, the combination with a short-wall mining machine comprising a chain kerf-cutter connected to a frame adapted to rest on and slide over a mine floor when the machine is fed transversely of the kerf-cutter, of a cuttings removal unit attached to said mining machine in position to receive cuttings from said kerfcutter and .sweeping them in a direction away from the mining machine, said cuttings removal unit comprising a supplemental frame having a base plate movable bodily with the mining machine frame over the mine floor, and a removable deflector at the advancing edge of said base plate and inclined rearwardly from the advancing side of the mining machine frame in a direction away from the kerf-cutter, means for driving said outtings removal unit from said mining machine including bodily feed in accordance with the direction of feed of the mining machine, and a pair of spaced-apart symmetrically arranged upright curved deflectors mounted adjacent one end of the chain cutter, one of said pair of deflectors acting to direct the cuttings to said unit when the mining machine is fed in one direction and the other deflector acting to direct the cuttings to said unit when the mining machine is fed in,

the opposite direction, the said inclined deflector being adapted to be connected to whichever edge of the base plate is the advancing edge depending upon the direction of feed of the mining machine transversely of said chain cutter and transversely of said base plate.

11. In mining apparatus, the combination with a mining machine having a chain kerf-cutter, of a support comprising a horizontal ground engaging base plate connected to said mining machine, a cylindrical member mounted on said support abovesaid horizontal ground engaging base plate to rotate relatively to the latter on a vertical axis, a flight adapted to project at both ends from said cylindrical member, means for rotating said cylindrical member relatively to said horizontal ground engaging base plate to effect rotation of saidflight, and means secured to said base plate and engaged by said flight to effect reciprocation thereof to vary the projections of its I ends from said cylindrical member.

12. In mining apparatus, the combination with a mining machine having a chain kerf-cutter,

of a horizontal ground engaging support connected to said mining machine so as to be nonrotatable relatively thereto, a rotary member mounted on said support to rotate relatively thereto on a vertical axis, a flight connected to said rotary member to reciprocate radially thereof and alternately project from diametrically opposite sides of said rotary member, both ends of said flight being adapted to be projected from said rotary member one after the other, means for rotating said rotary member on its vertical axis relatively to said horizontal ground engaging support to effect rotation of said flight, and means secured to said horizontal support in position to be engaged by said flight during its rotation to effect reciprocation thereof and alternate projections of the ends of said flight from diametrically opposite sides of said rotary memher to effect maximum projection of such flight when adjacent said kerf-cutter and minimum projection of said flight when remote from said kerf-cutter.

13. In mining apparatus, the combination with a mining machine embodying a chain kerf-cutter, of a cleaning unit connected to said mining machine for operation thereby and comprising a non-rotatable base plate and a flight with a drum connected thereto to drive the same, an upright abutment provided with an inner surface having the shape of a segment of a cylinder concentric with said drum and in close proximity to the outer cylindrical surface thereof, and a cam secured to said base plate in position to be engaged by the flight for effecting projection of the latter from the drum when spaced from said abutment and the retraction of such flight when moving along said abutment, the flight being confined to a path concentric with the rotation of the drum.

14. In mining apparatus, the combination with a short-wall mining machine including a chain kerf-cutter bar connected to the front end of a frame adapted to rest on and slide over a mine floor when the machine is fed transversely of the kerf-cutter, a cutter chain on said kerf cutter extending along the bottom of said machine to a drive sprocket adjacent the rear end thereof, of cuttings removal mechanism at the rear end of said mining machine and rearwardly of said cutter chain and driving sprocket and in position to receive cuttings from said cutter chain and sweep them in a direction away from the mining machine while being positioned within the lateral confines of the mining machine frame, said outtings removal mechanism including a base plate, a drum mounted for rotation on an upright axis, sweeping blade means adapted to project and recede from said drum as they rotate therewith, and a pair of laterally spaced-apart symmetrically arranged upright curved deflectors mounted adjacent said cutter chain drive sprocket rearwardly thereof, one on each side thereof, one of said pair of deflectors acting to direct the cuttings from said chain to said removal mechanism when the mining machine is fed in one direction and the other deflector acting to direct the cut- -tings thereto when the mining machine is fed in the opposite direction.

15. In mining apparatus, the combination with a short-wall mining machine including a chain kerf-cutter bar connected to the front end of a frame adapted to rest on and slide overa mine floor when the machine is fed transversely of the kerf-cutter, a cutter chain on said kerf cutter extending along the bottom of said machine to a drive sprocket adjacent the rear end thereof, of cuttings removal mechanism at the rear end of said mining machine and rearwardly of said cutter chain and driving sprocket and in position to receive cuttings from said cutter chain and sweep them in a direction away from the mining machine, said cuttings removal mechanism including a base plate, a drum mounted for rotation on an upright axis, sweeping blade means adapted to project and recede from said drum as they rotate therewith, and a pair of laterally spaced-apart symmetrically arranged upright curved deflectors mounted adjacent said cutter chain drive sprocket rearwardly thereof, one on each side thereof, one of said pair of deflectors acting to direct the cuttings from said chain to said removal mechanism when the mining machine is fed in one direction and the other deflector acting to direct the cuttings thereto when the mining machine is fed in the opposite direction.

16. In mining apparatus, the combination with a short-wall mining machine including a main frame having a motorthereon .and a kerf cutter bar extending forwardly thereof, of a cutter chain mounted on said cutter bar and extending rearwardly along said main frame and below said motor and around a drive sprocket at the rear end, a driving connection between said motor and sprocket providing for reverse driving of said sprocket and cutter chain whereby said machine may cut kerfs while feeding said cutter bar laterally in opposite directions, and cuttings removing mechanism mounted within the lateral confines of said main frame and closely adjacent the rear run of said cutter chain and operative to receive cuttings carried rearwardly by said cutter chain and adapted to discharge them from said machine for reverse operation thereof and reverse travel of said cutter chain, said cuttings removing mechanism including a drum rotating on an upright axis and having flight means projecting therefrom and reciprocating relative to said drum during operation, the aforedescribed construction providing a compact short-wall type mining machine.

. FLORENCE H. C. JEFFREY,

Executrim of the Estate of Robert K. Jeflrey,

Deceased.