US2349311A

US2349311A - Mining machine

Info

Publication number: US2349311A
Application number: US389016A
Authority: US
Inventors: Leon E Simmons
Original assignee: Sullivan Machinery Co
Current assignee: Sullivan Machinery Co
Priority date: 1941-04-17
Filing date: 1941-04-17
Publication date: 1944-05-23
Anticipated expiration: 1961-05-23

Description

y 1944- L. a. SIMMONS 2,349,311

MINING MACHINE Filed April 17, 1941 4 Sheets-Sheet 1 75 69 zo g' "W "u i n 87 i wnior: [/4 2/ [/5 I ain 'zmmans. He 0 34 AMI-mm- 3 5 (lug).

MINING MACHINE Filed April 17, 1941 4 Sheets-Sheet 2 o o E? Q o s any.

May 23, 1944. l... E. SlMMONS mama moamn Filed April 17, 1941 4 Sheets-Sheet 3 63 [n uenbr: g W i; leonES'unmana.

67 A'Mbuvh any May 23, 1944.

L. E. SIMMONS MINING MACHINE Filed April 17, 1941 4 Sheets-Sheet 4 107 g t'o HIM Inve nfor: leanl'zd't'vnmona'.

Patented May 23, 1944 MINING MACHINE Leon E. Simmons, Ciaremont, N. H., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application April 17, 1941, Serial No. 389,016

11 Claims.

This invention relates to mining machines, and more particularly, but not exclusively, to improvements in coal mining machines of the flexibly fed, room and pillar type.

An object of the present invention is to provide an improved coal mining machine of a relatively simple, rugged and compact construction. Another object is to provide an improved and novel motor arrangement whereby the vertical dimensions of the machine may be kept at a minimum. A further object is to provide an improved coal mining machine having improved kerf cutting mechanism. Yet another object is to provide animproved arrangement of the machine motor with respect to the cutter bar of the kerf cutting mechanism wherein a portion of the motor is recessed within the cutter bar to reduce the overall height of the machine. A still further object is to provide an improved cutter bar construction for a coal mining machine. Another object is to provide an improved coal mining machine 01 the room and pillar type wherein the cutter bar projects horizontally beneath the machine motor to enable discharge of the cuttings from the rear of the machine and is constructed withthe view of keep e tical dimensions of the, machine as low as p ssible. Another object. is to provide an improved motor and cutter bar construction wherein guides for the cutter chain are secured to the motor casing, and t he bottom portion of the latter is recessed Within the cutter bar. Other objects and advantages of the invention will,.however, hereinafter more fuflrappem as the description pro ds. Y

, In the accompanying drawing there is shown for purposes 01 illustratio none form which the invention may assumeinpractice.

In these drawings Fig. l is. a plan view of vaco al miningmachlnc constructed in accordance with an illustrative embodiment oithe inventi n.

Fig. 2. is a sidejelelvational view of th mining machine shown inFie.

Fig. 3 is a rear end elevational, view of the mining. machine. v v L h Fig. 4 is an. enlarged view in. ,longitudinalverttcal section taken substantially, on line 4-4 of Fig. l.

Fig. 5 is a cross sectional tially on line 5-5 of 4,.

Fig. 6 is a horizontal sectional view taken substantially on line 6-6 at 4. v

Fig. 7 is a detail sectional view taken on line 1-1 01 6.

view taken substan- Fig. 8 is a horizontal sectional view taken substantially on line B8 of Fig. 4.

Fig. 9 is a fragmentary cross sectional view taken on line 9-9 of Fig. 4.

Fig. 10 is a perspective view of the rearward portion of the cutter bar.

Fig. 11 is a fragmentary perspective view of the bottom portion of the motor casing.

In this illustrative embodiment of the invention there is shown a coal mining machine of the flexibly fed, room and pillar type adapted to rest upon and slide in any direction over the mine floor. It will be evident, however, that various features of the invention, without de parting from its spirit, may be incorporated in coal mining machines of various other types.

In this illustrative construction, the mining machine comprises a main frame I mountedon a hottomskid plate 2 which slideson the mine floor. Extending longitudinally through the bottom of the main frame is a horizontal chamber 3 having arranged and supported therein the rearward portion of a cutter bar 4 of an improved design. The cutter bar projects forward- 1y of the main frame and has an endless cutter chain 5 movable thereabout in an orbital path. A motor 6 is mounted within the forward portion of the main frame and has its casing .1 integral with the main frame, and the. motor casing has its lower portion recessed within the cutter bar in a novel manner to. be later fully explained. The rearward portion of themain frame is formed to provide a chamber ii within which elements ofthe keri cutting mechanism andthe machine feeding means are arranged, as will also be described. 1

The motor 6 is herein an electric motor and has an armature 9 keyed to an armatur shaft 49. The motor haseompound wound field coil assemblies II, and arranged between these coils are commutating pole and coil assemblies i2. The lower one of the field. coil assemblies II is arranged in part below a horizontal plane in which the top surface of the cutter-bar lies and within the orbit of the endless cutter chain. The armature shaft H] of the motor is horizontally disposed and extends longitudinally of the machine with its axis of rotation lying in the central longitudinal vertical plane of the machine. and is suitably journaled within the motor casing.

Now referring to the cutter chain driving means, it will be noted thatsecuredjto the rear end of the motor armature shaft. I0 is a bevel pinion l3 meshing. with a large horizontal bevel gear I 4 havin its hub keyed to a vertical hollow shaft l5. Extending through the hollow shaft I5 is a vertical shaft l5, and the shaft I5 is Journaled on ball bearings supported by the shaft 15, in the manner shown in Fig. 4. Formed on the upper portion of the hollow shaft l5 are clutch teeth I1 connectible by a sliding clutch member ii to the teeth of a clutch member I! keyed to the upper end of the shaft I5. ,The upper end of the shaft I6 is iournaled through the hub of the member is in a ball bearing supported by the detac able top cover plate of the main frame, nhaft I6 is Journaled near its lower end wit all bearings supported by a detachable bottom plate 2|. Keyed to the lower end of the shaft I5 and driven'thereby and arranged in the chamber 8 is a chain sprocket 22 which engages and drives the endless cutter chain 5. It will thus be seen that when the clutch member I8 is connected the cutter chain may be driven from the motor through the bevel gears II, l4, hollow shaft [5, the vertical shaft IB and the cutter chain sprocketffl. The operating means for the clutch member l8 comprises a shipper yoke 23 pivotaliy mounted at 24 within ther'nain frame and having its rearward portion engaged by a crank 25. This crank is formed on "an operating shaft 25 suitably Journaled within the rear wall of the main frame and has secured thereto an operating handle 21.

The flexible feeding means comprises a feed drum 3| and a controlling or retarding drum 32, thesed'ruins being arranged rearwardly of the motor at the opposite sides of the main frame on horizontal" axes extending transversely of the machine. Respectively wound on these drums aregfeeding and, controlling

cables

33 and 84. These cable winding drums are respectively

journaled'on'stub shafts

85 and 86 projecting laterallyfrom

detachable brackets

31 and 88 secured to theopposite sides of the main frame, andarranged between the drum hubs and the stub shafts are eccentric bushings whereby the drums may be freed from their driving gearlngs, in a manner fully described in Patent No. 2,131,178 idtihi'li' I am coinventor. As ,these eccentric bushing drum releasedevices do not per Se enter into this invention, further description thereof is unnecessary.

Thedrum driving means, in this instance, commists aworrii 35 formed on the vertical hollow shaft I5 and meshing with a worm wheel u havingitshub keyed to a horizontal shaft 41. This snsreextencs transversely of the main frame inwardly of the shaft l5 and is suitably journaled within ball bearings supported within hearing brackets 42. Secured to the'shaft II is a spur pinion meshing with an internal gear 44 having its hub journaled 'on a ball bearing supported By'a stub shaft 45,"'the latter having a pressed fit within a bore in the adjacent bracket 42. Alined with-the stub shaft 45 is a shaft 45 Journaledfgit its inner end on a roller bearing supportedby the stub'shaft 45 and at its outer end within a'balljbearing supporting by the adjacent drum-bracket, 51. The internal gear 44 is connectible it the shaft as by a conventional multiple disc clutch 41; and the shaft has keyed thereto and drives a spur ear 48 meshing with an interhal gear 49 on thg feed drum 3!. Also secured tothe shaft 4| is aspur gear 50 meshing with a spur gear 5| journal'ed on a ball bearing supported by astub' shaft 52. This stub shaft has a pressed fit within a bore in the adjacent bracket 42,- in a manner similar to the stub shaft 45. Alined with this stub shaft is a shaft 53 journaled at its inner end on a roller bearing supported by the stub shaft 52 and at its outer end within a ball bearing supported within the adjacent bracket 38. The gear 51 is connectible to the shaft 53 by a conventional multiple disc clutch 54. The shaft 52 has keyed thereto and drives a spur gear 55 meshing with an internal gear 55 ontthe controlling drum 32. Coaxial with the clutch 54 is a brake 51'for retarding rotation of the controlling drum 32 when the friction clutch is released, in the manner to be later explained. This brake comprises a sleeve 58 keyed to the shaft 53, and connected to this sleeve is a series of friction plates which are interleaved with a series of friction plates connected to a sleevelike member 59 rigidly secured to the adjacentdrum bracket 38.

The clutches 41 and 54 and the brake 51 have operating means including shipper rings 54 and GI slidable relative to the shafts 4B and 53, respectively, and have projecting fingers engageable with the end pressure plates o'fthe clutches and brake. Since the actuating means for the shipper rings are identical, a description of the actuating means for the shipperrir'ig 6| w'ill sufflee for both; Engaged in an annular groove on the shipper ring 5| is a shipper yoke 82 pivotally mounted on a vertical shaft 53 secured within the machine frame. The shipper yoke has an integral lever arm 54 provided with a guide slot extending radially with respect to the yoke pivot axis, and engaged in this guide slot is a ball bearing thrust roll 86 carried by a crank 61 integralwith a vertical operating shaft 5B. This shaft is suitably Journaled within a bearing bracket integral with the cover plate 20 and has an operating handle 59 extending rearwardly over the top of the main frame. This operating lever has a grasping portion 10 conveniently located at the rear, end of the machine. When the clutch levers are swung inwardly, the shipper rings 6|], 5| are moved toward one another, thereby to effect application of the disc clutches 41 and 54, and when the levers are swung outwardly the clutches are released, Further outward movement of the lever controlling the clutch shipper ring Bl eil'ects loading of the discs of the brake 51. It is accordingly evident that the feed drum ,3! may be driven in cablewinding direction at a relatively low feeding" speed through the worm gearing 89, 40, pinion 43, internal gear 44, the clutch 41, shaft 45 and the gear 48 meshing with the internal gear 49 on the feed drum, under the control of the disc clutch. The controlling or retarding drum 32 may be driven in cable winding direction at a relatively high speed through the worm gearing 59, 40, spur gearing 50, 5|, clutch 54, shaft 53, and the gear 55 meshing with the internal gear 55 on the drum, under the control of the disc clutch 54. Also, rotation of the controlling drum 32 in cable unwinding direction may be frictionally resisted by the dis'cbrake 51. By adiustingthe eccentric bushings for the drum hubs relative to the stub shafts, the drums may be moved eccentrically to throw out the drum gears from meshing engagement with their driving gears, thereby to obtain free drum rotation. This feature, which is well known in the art, permits easy winding of the cables on the drums by hand.

The feeding and controlling drums 3| and 32 and their driving gearings maybe transposed to the opposite sides of the main frame so that the machine may operate from right to left instead of from left to right as shown. Upon such transposition of parts, it is necessary to provide new drum brackets, but otherwise no additional parts are needed. It is accordingly evident that. by but slight modification the machine may be readily transformed into a left to right machine. This is highly desirable since some mines operate the coal mining machine in one direction under certain conditions and in the other direction under other conditions. The feed mechanism just described as well as the truck drive means hereinafter described, are described and claimed in my copending application Serial No. 414,721 which is a division of this application.

Provision is made whereby the machine motor may effect drive of the propelling means of a transport truck, and this truck driving means comprises, as shown most clearly in Fig. 6, a spur gear I2 keyed to and driven by the shaft 4|. This gear meshes with a spur gear I3 secured to a parallel shaft I4 suitably journaled within a housing I5 attached to the rear end of the main frame. Keyed to and driven by this shaft is a spur gear I6 meshing with a spur gear 11 having its hub keyed to a sleevelike member I8 journaled within the housing I5. This sleevelike member is connectible by a conventional multiple disc clutch I9 to a coaxial shaft 80 likewise suitably journaled within the housing. Keyed to and driven by this shaft is a chain sprocket 3| adapted to engage an endless drive chain (not shown) of the truck propelling means. This clutch is operable by a clutch-applying member 82 having a rodlike portion 83 slidably guided in a bushing 84 supported within the housin I5. This member 82 has fingers engageable with the end pressure plate of the clutch. Interposed between a flange on a member! ladjustably secured to the rodlike portion 83 of the clutchapplying member) and the housing, is a coil spring 86 for yieldingly urging the clutch-applying member towards its released position. Pivotally mounted on the housing is a lever 81 having a projection 88 engageable with the member 85. It will thus be seen that the truck ropelling means may be driven from the machine motor through the bevel gears I3, [4, worm gears 39, 40, spur gears I2, I3 and spur gears 16, ll under the control of the disc clutch 19.

Now referring to the improved structure of the cutter bar 4. is will be noted that secured. in a suitable manner, as by rivets, to parallel side bars 90. 90 are top and bottom plates ill and 92. These plates cooperate with the s de bars to provide a guideway 93 about the mar in of the cutter bar. and in this euidewav the end ess cutter chain 5 may be circulated for orbital movem nt. This cutter chain extends about the cutter cha n euideways through the chamber 3 w thin the lower part of the main frame and a ound the cutter chain driving sprocket in the manner clearly shown in Fig. 8. and the s de ba s of the cutter bar are laterally inwardly inclined at M to direct the cutter chain into proper re ation with the cutter chain sprocket. Suitab y secured, as by rivets, to the bottom sk d plate 2 and extending longitudinally within the chamber 3 in a position midway between the sides of the main. frame is a bottom step plate 95 having on its upper surface a centrally located longitudinal roove or slot 96. and the casino. 1' of the motor has a rectangular bottom projection 91 fitted within this groove or slot and suitably rigidly secured, as by screws 93, to the step plate 95. The upper sides of the rearward portions of the side bars 90, 90 are relatively inwardly inclined or converge inwardly at 99, and the surfaces of these inclined portions engage complemental inclined surfaces I00, I00 on the bottom portion of the motor casing I, in the manner clearly shown in Fig. 5. These rearward portions of the side bars extend longitudinally along the opposite sides of the bottom motor projection 91. Suitably detachably secured, as by screws H, to bottom plane surfaces I02 on the motor casing are liners I03, and similar liners HM are suitably secured, as by rivets, to the side flanges of the step plate, and these liners cooperate to provide the side guiding surfaces for the cutter chain, so that when the chain leaves the guide surfaces of the top and bottom plates SH, 92 it moves between and is guided by these liners on the motor casing and step plate. The lower bar plate 82 is centrally slotted at I06, and bar hanger Hi! suitably secured, as by rivets, to the bottom skid plate, has a portion H18 fitted within this slot between the side bars 98, 9D, in the manner shown in Fig. 8. This bar hanger provides guideways along which the cut.- ter bar is slidably guided, so that the bar may be adjusted by conventional means (not shown) to tighten the cutter chain. During her adjustment the surfaces of the rearward side bar projections slidingly engage the complemental surfaces on the motor casing and bottom step plate. in an obvious manner.

To maintain the proper power characteristics of the motor and to conserve in its height the bottom field coil assembly II of the motor is recessed within the cutter bar. in the manner above explained. thereby to reduce the eifective height of the machine. Thus. the motor casing is constructed so that a portion thereof is beneath and is intersected by a horizontal plane. indicated constructively at P in Fig. 5, in which plane is the line traced by the cutting po nts of the uppermost bits; and the outermost limits of the orbit of the cutter chain lie outside the vertical projection of the lateral boundar es of the motor casing. A. horizontal plane parallel A with and below the plane P intersects the cutter hain, the cutter bar and the depending portion of the motor casing, and the depending. motor casing portion extends below a horizontal plane n which the bottom surface of the cutter bar lies. Also, as above explained, the motor casing provides a support for one of the guiding elemcnts for the cutter chain and also provides an extremely stable support for the rearward portion of the cutter bar. Furthermore, the lowest portions of the lowest field pole, and indeed of the lowest field coil, extend below the horizontal plane at the top of the cutter bar.

As shown in Fig. 4, the rearward portions of the top and bottom plates SI and 92 of the cutter bar terminate within a recess IID beneath a detachable front head III of the motor, and the bar hanger I0! is, in part, located within this recess. Also, as illustrated. the rear ends of the side bars 90, 90 of the cutter bar terminate at po nts slightly rearwardly of the bottom step plate 95 in the space between the rear end of the latter and the chain sprocket 22. It is evident that as the cutter chain is circulated in its orbit about the margin of the cutter bar. the cuttings created by the cutter of the chain are moved through the bottom chamber 3 to discharge at the rear end of the machine and the opposite runs of the cutter chain move through the chamber along the opposite sides of the bottom portion of the motor casing. The horizontal plane P, indicated diagrammatically in Fig. 5, lies at the top of the cutter chain orbit and intersects the bottom field coil assembly H and the bottom of the motor casing, in the manner shown. By the construction provided, the motor and cutter bar are rendered extremely vertically compact, and by utilizing a part of the motor casing as a support for guiding elements for the cutter chain, the structure is simplified and made more rugged.

The general mode of operation of a coal mining machine of the type disclosed is well known to those skilled in the art, and, therefore, a detailed description thereof is considered unnecessary. The machine is provided, in a usual mannor, with a number of suitably located rear guide sheaves H2, H3, H4, H5 and H6 and a pair of front guide sheaves I H, I I8, and the feeding and controlling

cables

33, 34 may be extended from their respective drums in various directions around these guide sheaves, in a well known manner, and the free ends of the cables may be anchored at remote points near the ribs 01 the room at the opposite sides of the coal face. The machine may be fed forwardly in an endwise direction near one rib to sump the cutter bar beneath the coal. Thereafter the machine may be fed laterally to move the cutter bar transversely across the coal face, and finally the machine may be angled with respect to the other rib and moved rearwardly to withdraw the cutter bar from beneath the coal to complete the cut. During the various operations of the machine, the feed drum 3i may be rotated at a relatively low cutting speed under the control of the disc clutch 51 in a direction to wind in the feed cable 33, and the controlling drum 32 may be rotated in cable unwinding direction under the control of the brake 51. If desired, the controlling drum 32 may be driven at a relatively high speed in cable winding direction under the control of the disc clutch 54. When the cutter chain drive clutch member I8 is connected, the cutter chain may be rapidly circulated within its guideways along the bottom of the main frame and about the margin of the cutter bar, and when this clutch member is released the cutter chain may remain idle durin running of the motor. The propelling means of the machine transport truck may be driven from the machine motor under the control of the disc clutch 18.

As a result of this invention it will be noted that an improved coal mining machine of relatively simple, rugged and compact construction is provided having an improved and novel motor and cutter bar arrangement whereby the vertical dimensions of the machine are rendered extremely compact. It will also be noted that by recessing the motor within the cutter bar and by providing guides for the cutter chain on the bottom of the motor casing, the motor is not only rendered extremely low in height but also the cutter chain is guided in an improved manner. Other uses and advantages of the improved mining machine will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that i this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a mining machine, the combination comprising a main frame, a horizontal motor having a motor casing, a horizontal plane cutter bar having a cutter chain movable in an orbit about its margin, said motor casing having its bottom portion lying within the cutter chain orbit, and said main frame and motor casing providing guideways for slidingly receiving and supporting the rearward portion of said cutter bar.

2. In a mining machine, the combination comprising a horizontal plane cutter bar having an endless cutter chain movable in an orbit about its margin, said bar having spaced apart parallel rearward projections, and a horizontal motor for driving said cutter chain having a motor casing a bottom portion of which projects downwardly between said parallel bar projections, and said bar projections having inwardly inclined upper surfaces in supported engagement with complemental inclined surfaces on the bottom of said motor casing.

3. In a mining machine, the combination comprising a horizontal plane cutter bar having spaced apart parallel rearward portions, a cutter chain movable in an orbit about the margin of said cutter bar, and a horizontal motor for driving said cutter chain having a motor casing provided with a bottom projection, and a bottom step plate, the rearward bar portions extending along the opposite sides of said motor casing projection and engaging surfaces on said step plate and the bottom of said motor casing, said motor casing projection extending downwardly below a horizontal plane in which the bottom surfaces of said rearward bar portions lie.

4. In a mining machine, the combination comprising a horizontal plane cutter bar having spaced apart parallel rearward portions, a cutter chain movable in an orbit about the margin of said cutter bar, and a horizontal motor for driving said cutter chain having a motor casing provided with a bottom projection, a bottom step 7 plate, the rearward bar portions extending along the opposite sides of said motor casing projection and engaging surfaces on said step plate and the bottom of said motor casing, and a bar hanger secured to said step plate and having a portion projecting between said rearward bar portions and with which said cutter bar is slidingly enaged.

5. In a mining machine, the combination comprising a main frame, a horizontal motor having a motor casing, a horizontal plane cutter bar having a cutter chain movable in an orbit about its margin, said motor casing having a bottom portion thereof projecting downwardly within the cutter chain orbit, and said main frame and motor casing providing guideways extending longitudinally along the opposite sides of said downwardly projecting bottom portion of said motor casing for slidingly receivin and supporting the rearward portion of the cutter bar.

6. In a mining machine, the combination comprising a main frame, a horizontal motor having a motor casing, a horizontal plane cutter bar having a cutter chain movable in an orbit about its margin, said motor casing having a relatively narrow bottom portion lying within the cutter chain orbit, and said main frame and motor casing providing longitudinal guideways for slidingly receiving and supporting the rearward portion of said cutter bar, said guideways being so arranged that a horizontal plane passing through said bottom portion of said motor casing also passes through said guideways.

7. In a mining machine, the combination comprising a main frame, a horizontal motor having a motor casing, a horizontal plane cutter bar having a cutter chain movable in an orbit about its margin, said motor casing having a relatively narrow portion of its bottom projectin downwardly within the cutter chain orbit, said main frame and motor casing providing longitudinal guideways for slidingly receiving and supporting the rearward portion of said cutter bar, and said bottom portion of said motor casing projecting below a horizontal plane in which the top of the cutter chain orbit lies and said guideways being arranged below said horizontal plane.

8. In a mining machine, the combination comprising a main frame, a horizontal motor having a motor casing, a horizontal plane cutter bar having a cutter chain movable in an orbit about its margin, said motor casing having a portion of its bottom projecting downwardly within the cutter chain orbit, said main frame and motor casing providing longitudinal guideways for slidingly receiving and supporting the rearward portion of said cutter bar, and said bottom portion of said motor casing projecting below a horizontal plane in which the top of the cutter chain orbit lies and said guideways being arranged below said horizontal plane and being so arranged that a parallel plane below said plane passes through both said bottom portion and said guideways.

9. In a mining machine, the combination comprising a main frame, a horizontal motor having a motor casing, a horizontal plane cutter bar having a cutter chain movable in an orbit about its margin, said motor casing having a relatively narrow portion of its bottom projecting downwardly within the cutter chain orbit, said main frame and motor casing providing longitudinal guideways for slidingly receiving and supporting the rearward portion of said cutter bar, and said guideways and said downwardly projecting bottom portion being disposed below a horizontal plane in which the top boundary of the cutter chain orbit lies.

10. In a mining machine, the combination comprising a horizontal plane cutter bar having spaced apart parallel rearward portions, a cutter chain movable in an orbit about th margin of said cutter bar, a horizontal motor for driving said cutter chain having a motor casing which has its portion of greatest width disposed above said cutter bar and provided with a relatively narrow bottom projection of substantially less width than the width of said motor, and a bottom step plate, said rearward bar portions extending along the opposite sides of said bottom motor casing projection and engaging surfaces on said step plate and the bottom of said motor casing, and said motor and said cutter bar being so arranged and constructed that the motor extends down within the cutter bar thereby to maintain the vertical dimension of the machine at a minimum,

11. In a mining machine, the combination comprising a, main frame, a horizontal motor carried by said frame and having a motor casing, a horizontal plane cutter bar projecting from said frame and having a cutter chain movable in an orbit about its margin, said cutter bar being guided for adjustment longitudinally relative to said frame and said motor, said motor casing having its portion of greatest width disposed above said cutter bar and provided with a relatively narrow bottom portion lying within the cutter chain orbit, said motor and said cutter bar being so arranged and constructed that the motor extends down within the cutter bar thereby to maintain the vertical dimension of the machine at a minimum, and said bottom portion of said motor casing and said main frame cooperating to provide longitudinal guideways for slidingly receiving and supporting the rearward portion of said cutter bar.

LEON E. SIMMONS.