US2307966A - Mining machine - Google Patents

Description

Jan. 12, 1943. w. w. sLoANE MINING MACHINE 4 Sheets-Sheet 1 Filed Oct. 3, 1941 T N p E W 3 QM m w m M Y B Kali n U n w JQ 4 b F h I n. H/ v v "1 i n ||L \VQMV. QQV N, W

, ATTOlNEY Jan. 12, 1943.

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, 1941 4 SheerLs-Sheet 2 IN V EN TOR. WLllwn )4. 810mm pusg ATTORNEY Jan.- 12, 1943. w; w SLQAQNE I 2,30 7, 66

MINING, MACHINE Filed Oct. 3, 1941 4 Sheets-Sheet 3 INVENTOR.

WilZmm )1! Sloane ATTORNEY Patented Jan. 12, 1943 UNITED STATES PATENT OFFICE MINING MACHINE Application October 3, 1941, Serial No. 413,397

2 Claims.

This invention relates to improvements in min ing machines wherein a kerf-cutting element is adjustably mounted on a base frame having rubber tired wheels affording traction and steering means for the machine.

One of the principal diiiiculties which are encountered with machines of the character above described is that of maintaining the base frame in a uniform cutting plane when the cutter bar is swung at an angle toward one side of the machine or the other. Unbalancing of the machine in this manner has a tendency to depress the pneumatic tires on the side toward which the cutter bar is swung, with the result that said outter bar is likely to become wedged in the'kerf while cutting across the front of the machine. Accordingly, it has commonly been found necessary .to limit the degree of lateral swing of the cutter bar to relatively small angles which, for instance, are much smaller than a full 180 cutting arc, which is wholly practical when machines of substantially the same types are supported on track wheels. Obviously, such limitation of cutting angle greatly reduces the inherent efficiency of a kerf-cutting machine when mounted on rubber tires.

In carrying out my invention, I provide an improved and simple form of tilting and equalizing mechanism for the front supporting wheels of the vehicle, including a pair of hydraulic jack devices for counterbalancing any lateral tipping effect on the machine frame due to excessive depression of the tires. Said jack devices have selective control means conveniently arranged for manipulation by the operator, as may be required under varying cutting conditions.

The invention may best be understood by reference to the accompanying drawings, in which:

Figure 1 is a plan view of a kerf-cutting machine constructed in accordance with my invention, with parts broken away to show certain structural details;

Figure 2 is a side view of the machine shown in Figure 1, with parts shown in section;

Figure 3 is an enlarged front view showing the chassis of the machine and the front supporting wheels, with certain parts in section;

Figure 4 is a detail plan view of the front end of the chassis and the front supporting wheels, with the wheel axle and differential drive mechanism shown in horizontal section;

Figure 5 is a section taken generally on line 5-5 of Figure 4;

Figure 6 is an enlarged detail section of the steering mechanism, taken generally on line 5-6 of Figure l, but with the steering wheels swung at an angle of Figure 7 is a detail section of the steering mechanism, taken on line 1-1 of Figure 1.

Referring now to details of the embodiment of my invention illustrated in the several figures of the drawings, the same is shown as applied to a mounted kerf-cutting machine of a conventional form which has heretofore been mounted on track wheels for propulsion and guiding along track wheels. Such machines are well known so a detailed description thereof need not be made herein, excepting to point out the principal elements, and particularly those parts which are involved in the application of my invention thereto.

The machine shown in the drawings includes a base frame 10, having a turntable ll mounted at its forward end, having a plurality of upright supports I2, l2 thereon, between which is mounted, as usual, a supporting frame l3 arranged for vertical adjustment as by rack and pinion devices I4, M. The supporting frame I 3 has a chain carrying cutter bar l5 of the usual form projecting from its forward end, driven through the usual intermediate reduction gearing by a motor l6 mounted on its rear end. The rack and pinion devices I4, M are also driven by the motor [6.

The turntable H is rotated by a motor I"! mounted on a rear platform I8 of the base frame, said motor being operatively connected to said turntable as usual through a train of gears disposed rearwardly of the latter. The motor I! also provides power for driving the front wheels of the machine, as will presently be described.

Referring now to the rubber tired mounting for the machine, said mounting consists essentially of two wheel structures 20, 26 disposed at opposite sides of the main frame at the extreme front end thereof, and a single wheel structure 2| arranged for swivelling on a vertical axis at the rear end of the machine.

Each of the front Wheel structures 20 consist of a pair of wheels 22, 22 having pneumatic tires 23, 23 thereon, disposed side by side on a sleeve 24 forming in effect a common hub for both wheels. The two wheel hubs 24, 24 are rotatably mounted on opposite ends of a through axle 25 which is supported in journal . bearings 26, 26. Said journal bearings are of the box type, guided for vertical movement in depending pedestals 21, 21 fixed on and depending from horizontal frame members 28, 28 forming part of the base frame I0. Said journal bearings also have similar cylindrical portions 29, 29 extending outwardly therefrom through apertures 30, 30 in parallel, laterally spaced, equalizing levers 3 I], 3|.

The rear ends of equalizing levers 3|, 3| are pivoted on pins 3|a, 3|a carried on brackets 32, 32 depending from the'frame members 28, 28. The apertures 30, 30 in the equalizing levers are elongated longitudinally of said levers, as shown in Figure 5, so as to permit vertical movement of the front axle while the equalizing levers 3| move arcuately about their pivot pins 3 I a, 3 Ia.

The front ends of the equalizing levers have forwardly extending pins 33, 33 secured thereto, which have pivotal bearing near opposite ends of a cross bar 34 disposed below and spaced from a front end sill member 35, rigidly mounted at the front end of the base frame with its ends projecting laterally beyond the sides thereof, as shown in Figures 3, 4 and 5. A pair of jack devices 36, 36a, herein of the hydraulic type, are mounted in cylindrical recesses 31, 31 formed at opposite ends of the cross bar 34, with their extensible pistons 38, 38a normally in engagement with the ends of the end sill member 35. The jack devices 36, 33a are actuated individually by suitable manual control means, herein consisting of hand pumps 39, 39a mounted on the rear platform I8 of the machine in convenient position for manipulation by the operator (see Figures 1 and 2), and connected to the respective jack devices 36, 36a by flexible conduits 43, 40a.

With the tilting and equalizing mechanism above described, the front end of the base frame I0 is supported in a horizontal plane parallel to the front axle when the opposite ends of the sill member rest upon the tops of the pistons 38, 38a of the jack devices 33, 36a carried at the extreme ends of the cross bar 34, and said pistons are both in their normally retracted position, as shown in Figure 3. The equalizing levers 3|, 3| connected to the cross bar 34 will then be parallel to each other, and the wheel axle 25 will be parallel with the base frame. The machine will normally be propelled about the mine with the tilting and equalizing mechanism maintained in this position. However, when the cutter bar is swung laterally of the machine about the turntable axis, so as to throw more weight toward one side of the machine than the other, it will be understood that the loads on the two sets of front tires will become unequal so that one set of tires will be flattened 0n the ground more than the other. In order to overcome this unequal load or unbalancing of the front end of the machine, the operator manipulates that hand pump 39 or 39a which communicates with the jack device on the lower side of the frame, so as to extend the piston of said jack a suflicient distance to bring the base frame back to a plane substantially parallel with the mine floor. The cutter bar may then be sumped, as usual, by moving the entire machine forwardly toward the coal face with said cutter bar held in a stationary angular position. After the bar is sumped it may be swung as usual across the front of the machine to form an arcuate kerf. As the cutter bar approaches the longitudinal center line of the machine, its unbalancing effect will of course be gradually lessened. The operator compensates for this by gradually releasing pressure upon the proper hand pump. When-the cutter bar starts to swing towards the opposite sideof the machine the operator may then gradually increase the pressure upon the other hand pump as required to maintain the cutter bar in a substantially horizontal plane, to the end of the kerf.

From the above description it will be understood that it is advantageous to operate the two hand pumps independently of each other so as to meet varying cutting conditions as they may arise, and to allow for varying degrees of swinging movement of the cutter bar which may be employed for difierent cross cuts.

The drive connections to the front wheels includes drive sprockets 4|, 4|a mounted on the hub members 24, preferably between each pair of wheels, as shown in Figure 4. Said sprockets are connected respectively by chains 42, 42a. to sprockets 43, 43a at opposite ends of a differential drive structure indicated at 44.

The differential structure consists of an elongated hollow housing 45 secured in the brackets 32, 32 depending from the base frame. Said housing has a pair of anti-friction bearing members 46, 46 at opposite ends thereof providing rotatable support for opposite ends of a tubular differential casing 41. Said casing forms a driving member for the differential and has two aligned separate shafts 48, 4B rotatably mounted therein and operatively connected by a differential gear assembly of the usual form mounted within an enlarged centralportion 49 of said casing. Said gear assembly includes bevel gears 50, 50, fixed on the adjacent ends of the shafts 48, 48 and meshed with bevel gears 5|, 5| rotatably carried on the enlarged portion 49 of the differential casing.

The sprockets 43, 43a connected to the two front wheel structures 20, 20, as previously described, are mounted on the ends of the shafts 48, 48, which project at the opposite ends of the differential casing 41. Brake drums 52, 52a are also fixed on the extreme outer ends of the shafts 48, 48 beyond their respective sprockets 43, 43a, for engagement by brake bands 53, 53a respectively, as will presently be described. The differential gearing is driven through a sprocket 54 fixed on one end of the tubular differential casing 47 where it projects beyond the outer housing 45, as shown in Figure 6. The sprocket 54 is connected by chain 55 to the drive motor I! of the machine, through any suitable gear reduction mechanism, such as has heretofore been employed for driving the flanged wheels of track-mounted mining machines.

With the differential drive above described, the front wheel structures 23, 25 may be driven differentially so as to facilitate the turning movements of the machine while steering. The brake bands 53, 53a on the two brake drums 52, 52a may also be actuated independently of each other through any suitable manual control levers (not shown) so as to assist in controlling the steering and cutting movements of the machine through the front wheels, when desired.

The rear steering wheel structure 2| is mounted below the rear end of the base frame platform l8. In the form shown herein, said platform has an elevated recess formed by an arched circular bearing plate 55 which spans an opening 51 in said platform, and which is detachably secured as by bolts 58 to the under side of a flanged ring 58, surrounding the opening 51. The bearing plate 55 has an integral centrally disposed hollow sleeve 60 depending therefrom. An upright bearing support 6| is rotatably mounted in the lower end of said sleeve as by an anti-friction thrust bearing 62. Said bearing support has a control shaft 63 fixed therein and extending upapproach each other quite closely at their bottom tread surfaces.

The control shaft 63 has a worm gear 69 keyed on its upper end, and is meshed with a worm 10 on a horizontally disposed worm shaft A bevel gear 12 is keyed on one end of shaft H and is meshed with a bevel gear 13 on an upright steering post 14, having a hand wheel 15 thereon. The worm shaft H and steering post 14 have suitable bearings in enclosed casings 16 and 11, respectively, mounted on the top of the bearing plate 56. Thus the two wheels 66, 66 may be swivelled for steering in opposite directions by manipulation of the hand wheel 15.

Among the novel features not already pointed out is the novel mounting of the floating front axle and its equalizing levers 3|, 3| so as to increase the stability of the machine against lateral tipping. This is particularly important where, as here, the machine is mounted on rubber tires which are subject to variation in peripheral depression as the cutter bar is swung from one side of the machine to the other during cutting. It will be noted that due to the provision of the dual wheels at opposite ends of the front axle, it is necessary to place the equalizing levers 3|, 3|, which support said axle, in relatively close proximity to each other. Nevertheless, the cross bar 34, which is pivotally connected to the front ends of the equalizing levers 3|, 3|, is extended substantially beyond the latter, and the jack devices 36, 36a are disposed at the extreme ends of said cross bar. Thus the effective supporting base for the frame is widened considerably, so as to insure the desired stability of the machine.

As a further advantage it will be observed that most of the side thrusts on the floating axle are taken by the pedestals 21, 21, depending from the under side of the main frame, rather than by the equalizing levers 3|, 3|. This relieves the equalizing levers of undesirable torsional stresses which otherwise might tend to affect its proper functioning.

While I have herein shown and described one form in which my invention may be embodied it will be understood that the construction thereof and the arrangement of the various parts may be altered without departing from the spirit and scope thereof. Furthermore, I do not wish to be construed as limiting my invention to the specific embodiment illustrated, excepting as it may be limited in the appended claims.

I claim as my invention:

1. In a kerf-cutting machine, a frame having a projecting cutter bar pivotally mounted for lateral cutting movement across the front end of said frame, ground supporting means at the front end of said frame including a floating transverse axle having ground wheels adjacent opposite ends thereof, a pair of laterally spaced upright pedestals on said frame, and journal bearings for said floating axle guided for vertical movement in said pedestals, a pair of laterally spaced levers having weight-sustaining engagement with said floating axle intermediate their ends, said levers being fulcrumed on said frame at one end, a cross bar having pivotal connection with the free ends of said levers, and means for tilting said frame relative to said floating axle comprising a pair of independently operable extensible devices disposed in laterally spaced relation between said frame and said cross bar.

2. In a kerf-cutting machine, a frame having a projecting cutter bar pivotally mounted for lateral cutting movement across the front end of said frame, ground supporting means at the front end of said frame including a floating transverse axle having ground wheels adjacent opposite ends thereof, a pair of laterally spaced upright pedestals on said frame, and journal bearings for said floating axle guided for vertical movement in said pedestals, a pair of laterally spaced levers having weight-sustaining engagement with said floating axle intermediate their ends and being fulcrumed on said frame at their ends, and independently operable extensible devices interposed between the free ends of said levers and said frame for tilting said frame relative to said floating axle.

WILLIAM W. SLOANE.

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