US3405975A - Load dividing drive for single trimmer chain for boring miner - Google Patents

Description

Oct. 15,- 1968 E. F. BRILL LOAD DIVIDING DRIVE FOR SINGLE TRIMMER CHAIN FOR BORING MINER Filed June 22, 1966 l I I L w 3 Sheets-Sheet 1 INVENTOR. [om/.420 F5/LL Oct. 15, 1968 E. F. BRILL 3,405,975

LOAD DIVIDING DRIVE FOR SINGLE TRIMMER CHAIN FOR BORING MINER Filed June 22, 1966 5 Sheets-Sheet 2 INVENTOR.

fan 420 F 52/4L Oct. 15, 1968 E. F. BRILL 3,405,975

LOAD DIVIDING DRIVE FOR SINGLE TRIMMER CHAIN FOR BORING MINER Filed June 22, 1966 5 Sheets-Sheet 5 INVENTOR.

United States Patent 3,405,975 LOAD DIVIDING DRIVE FOR SINGLE TRHMMER CHAIN FOR BORING MINER Edward F. Brill, Uconomowoc, Wis., assignor to Westinghouse Air Brake Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed June 22, 1966, Ser. No. 559,614 3 Claims. (Cl. 299-59) ABSTRACT OF THE DISCLGSURE Load dividing drive for the single trimmer chain of a boring type continuous mining machine. The chain is trained inwardly of opposite ends of upper and lower trimmer bars trimming the floor and roof of the mine toward the center of the machine into a generally hourglass form about drive sprockets disposed midway between the trimmer bars and inwardly of the hubs of the boring heads. Each drive sprocket has its own tensioning roller and the two drive sprockets are positively driven at the same rates of speed by the drive gearing driving the rotary boring heads.

Background of the invention In continuous mining machines of the boring type in which two rotary boring heads mine contiguous bores in a mine face and the cusps between the boring heads, depending from the mine roof and extending upwardly from the mine floor, are trimmed by a single trimmer chain guided in vertically spaced rectilinear chain guides adjustable to extend along the roof and floor of the mine, the trimmer chain has usually been driven by a single sprocket and in training of the chain to pass from the lower to the upper trimmer bar and back to the lower trimmer bar and about its drive and idler sprockets, the chain has over 1000 degrees of direction changes. This adds to the friction which must be overcome by the drive, which is particularly serious as the machines become larger for mining thicker seams of coal or other minerals.

Summary and objects of the invention A principal object of the present invention is to remedy the foregoing difficulties by splitting up the loads on the trimmer chain and providing substantially equal tension on what would normally be the slack and tension runs of the chain.

Another object of the invention is to provide an improved drive for the trimmer chain of a continuous mining machine having a pair of contiguous boring heads and a Single trimmer chain guided to cut along the roof and floor of a mine and having spaced vertical runs guided to clear the boring heads of the machine, in which individul drive sprockets are provided for each vertical run, and tension means are provided for taking up tension on the chains at the outgoing sides of the drive sprockets to maintain substantially equal tension on the chain on the incoming and outgoing sides of the drive sprockets therefor.

A still further object of the invention is to provide an improved drive for the trimmer chain of a continuous mining machine guided for movement along vertically spaced trimmer bars positioned adjacent the floor and roof of a mine and having vertical runs guided by direction changing sprockets to extend inwardly and vertically of the ends of the trimmer bars, in which the direction changing sprockets are each drive sprockets and in which hydraulic tensioning means are provided in association with each drive sprocket at the outgoing side thereof for maintaining substantially equal tension on the chain on the incoming and outgoing sides of the drive sprockets therefor.

Still another object of the invention is to improve upon the drive to the trimmer chain of a continuous mining machine by so dividing the drive loads on the chain as to evenly divide the drive loads on the drive gearing for the chain, and to thereby impose one-half as much load on any given point on the chain, than in former drives for such chains.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawings wherein:

FIGURE 1 is a view in side elevation of a continuous boring miner constructed in accordance with the principles of the present invention;

FIGURE 2 is a front end view of the miner shown in FIGURE 1;

FIGURE 3 is a fragmentary horizontal sectional view taken through the drive to one of the trimmer chains; and

FIGURE 4 is a detail fragmentary partial front end view of the machine with certain parts broken away in order to show certain details of the tensioning means for the trimmer chain of the machine.

In the embodiment of the invention illustrated in the drawings, I have shown in FIGURE 1, a continuous mining machine of the multiple boring type having a mobile base or main frame 10 forming a support for a main supporting housing 11 extending in advance of said main frame. The main supporting housing forms a bearing support for a pair of laterally spaced rotary boring heads 12 supported in advance of said main supporting housing for rotation about parallel horizontal axes on opposite sides of the longitudinal center of said main frame and perpendicular to the working face of a mine. The main supporting housing also forms a housing and bearing support for gear trains (not shown) for driving said rotary boring heads at the same rates of speed, and a support for motors 14, 14 projecting from the rear end of said housing adjacent opposite sides thereof and forming a drive means for the gear trains drivng said boring heads.

The rotary boring heads 12 may be of conventional forms and are no part of the present invention except as to the cooperation of atrimrner chain 13 with said boring heads, so need not herein be shown or described further.

The main frame 10 is supported on laterally spaced continuous traction tread devices 15 (FIGURE 1), which serve to tram the machine from working place to working place and to feed the boring heads 12 into a mine face. The continuous traction tread devices 15 may be driven from indivdual motors and speed reducers (not shown) in a conventional manner, so herein not shown or described further.

The main supporting housing 11 also forms a support for an upper trimmer or cutter bar 16 extending across the forward end of said housing, in rearwardly spaced relation with respect to the boring heads 12, and forming a generally horizontal rectilinear guide for the trimmer chain 13, guiding said trimmer chain to trim the cusps depending from the mine roof and left between the boring heads 12 as said boring heads progress into the mine face. The trimmer bar 16 is mounted for adjustable movement with respect to the main supporting housing 11 on the usual hydraulic jacks 17, mounted at the forward end of the main supporting housing 11 in laterally spaced relation with respect to each other and extending vertically of said main supporting housing.

A lower trimmer bar 18 is disposed beneath and extends in parallel relation with respect to the ground or mine floor, in vertical alignment with the upper trimmer bar 16 and forms a rectilinear guide for the lower run of the trimmer chain 13, guiding said trimmer chain to trim the cusps left between the rotary boring heads 12 and projecting upwardly of the mine floor, in a conventional manner. The lower trimmer bar 18 is suspended from the main supporting housing 11 on a pair of laterally spaced vertically extending hydraulic jacks 19, and is held in fixed relation with respect to the ground by said jacks and vertically adjusted to be elevated above the ground during tramming, and to adjust the trimmer bar 18 to guide the trimmer chain 13 to out along the ground.

The main supporting housing 11 is adjustably supported on the forward end of the main frame to extend in advance thereof on fluid pressure jacks 21, secured to the rear end portion of the main supporting housing 11 at opposite sides thereof and supported on pivotal support members 22 of a conventional form. Control arms 23 extend rearwardly of the main supporting housing inwardly of motors 14 and may be mounted on the main frame 10 at their rear ends for universal movement, as shown in Patent No. 3,208,797 dated Sept. 28, 1965 and no part of the present invention so not herein shown or described further.

The drive gearing journalled within the main supporting housing 11 and driven by the two motors 14 is tied together to drive both of said rotary boring heads together at the same rate of speed. As shown in FIGURE 3 the drive gearing includes an individual spur gear 26, for driving each rotary boring head. Each spur gear 26 meshes with and drives a pinion 27 keyed or otherwise secured to a sprocket drive shaft 29 spaced inwardly of the axis of rotation of the rotary boring head and intermediate the upper and lower trimmer bars 16 and 18. Each drive shaft 29 extends along and coaxially of a sleeve 30, extending through and outwardly of a front wall 31 of the main supporting housing 11. The sleeve 30 has an intermediate radial flange 32 extending radially outwardly thereof and partially recessed in the front wall 31 (FIGURE 3). The radial flange 32 forms an annular projection for cap or machine screws 33, securing said sleeve to the wall 31 to extend forwardly therefrom in fixed relation with respect thereto. As shown in FIGURE 3, one machine screw 33 extends through an eccentric flange 35, extending radially of a collar 36, extending about the sleeve 30 for holding said collar from rotatable movement about the sleeve 30.

Each shaft 29 has a drive sprocket 45 on its outer end and is journalled at the forward end of the sleeve 30, on spaced anti-friction bearings 39, herein shown as being tapered roller radial thrust bearings. A drive disk is shown as being keyed to each shaft 29 at the forward end of the sleeve 30' and as having drive connection with an abutting drive disk 41, as by drive pins 43. The drive disk 41 in turn is bolted to an associated sprocket 45 by bolts 46, to form a drive member for said sprocket, and to accommodate ready removal of said sprocket from the drive shaft 29.

As herein shown, each sprocket 45 is a double toothed sprocket, having parallel spaced rows of teeth meshing between links 47 of the trimmer chain 13 and extending along opposite sides of connecting blocks 48 of said trimmer chain, for driving the trimmer chain in a conventional manner. The sprocket 45 is shown as being mounted on its shaft 29 on a bearing sleeve 49. An end cap 50 is secured to the end of the shaft 29 as by machine screws 51 and extends along the front end of the sprocket 45 and retains the associated sprocket 4-5 and drive disks 40 and 41 to said shaft.

As shown in FIGURES 1 and 2 of the drawings, the trimmer chain 13 passes about corner sprockets 53 at opposite ends of the trimmer bar 16 and changing the direction of a vertical incoming run of said trimmer chain to enter the trimmer bar at the end thereof, shown in FIGURE 2 as being the right hand end thereof, when looking toward the front of the machine, and changing the direction of said trimmer chain at the op osite end of said trimmer bar to pass angularly downwardly and inwardly to and about a drive sprocket 45. From the drive sprocket 45 the chain passes over a tension idler 55 and angularly outwardly and downwardly therefrom. about a corner sprocket 56 at the incoming end of the lower trimmer bar 18, to pass therealong, in a direction which in FIGURE 2, is shown as being from left to right. A corner sprocket 56 is provided at the outgoing end of the trimmer bar 18, and changes the direction of the trimmer chain 13 to pass vertically and angularly inwardly of the outgoing end of the trimmer bar 18 to and around an opposite drive sprocket 45. A tension idler 55 takes up tension on the outgoing side of the vertical run of the trimmer chain 13 as it passes from the drive sprocket 45 to the corner sprocket 53, at the incoming end of the trimmer bar 16.

The sprockets 45 thus drive the two vertical runs of the trimmer chain 13 as it passes from the trimmer bar 16 and into the trimmer bar 18 and passes from the trimmer bar 18 to be guided to pass along the upper trimmer bar 16, and the tension idlers 55 maintain substantially uniform tension on the chain at the incoming and outgoing sides of the drive sprockets therefor.

The two drive sprockets 45 thus drive each vertical run of the trimmer chain 13 and split up the loads on the chain so that the loads on the drive gearing are reduced in half and the loads on any given point on the chain are reduced in half.

As shown in FIGURE 3 each tension idler 55 is journalled on a pin 60 extending axially forwardly of the outer end of a tension arm 61, on anti-friction bearings 62. The tension arm 61 extends radially and angularly forwardly of a hub 63 mounted on a reduced end portion 64 of the sleeve 30 for pivotal movement with respect thereto. The hub 63 on one side of the machine has a bifurcated ear 65 depending therefrom. A piston rod 66 extensible from a fluid pressure cylinder 67 extends between the furcations of the bifurcated ear 65 and is pivotally connected thereto, as by a pivot pin 69. The cylinder 67 has a bifurcated connector 70 extending from its head end and extending along opposite sides of an ear 71 extending radially of the sleeve 36, and is pivotally connected to said car as by a pivot pin 72.

The opposite hub 63 has a bifurcated connector ear 65 extending upwardly therefrom, having the piston rod 66 of the opposite cylinder 67 connected thereto on a pivot pin 69. The cylinder is pivoted at its head end to an car 71 extending radially of the associated sleeve 36. The biasing connections for the two tension idlers 55 are thus the same so the same part numbers have been applied to each cylinder and its connectors. The cylinders 67 are supplied with fluid under pressure from the same source and may be connected in parallel relation to equalize the pressures of engagement of the tension idlers 55 with the trimmer chain 13 as it leaves the drive sprockets 45 to enter the trimmer bars 16 and 18 at the incoming ends thereof, and to thereby maintain substantially equal tension on each vertical run of the trimmer chain. It should he understood that while I have shown individual cylinders and pistons for taking up on the two vertical runs of the trimmer chain 13, that two cylinders need not necessarily be used but equal take up pressures on the idlers 55 may be attained by the use of a single cylinder, if desired.

Each take up arm 61 has a support plate 75 extending therefrom in a direction toward the incoming run of the trimmer chain and spaced axially inwardly of the outgoing run of said trimmer chain. The support plate 75 has a right angled support '76 extending forwardly therefrom and having a bearing pad 79 supported thereon in position to engage the incoming run of the trimmer chain 13 as it passes about its drive sprocket, in the extreme take up positions of the tension idler 65 to thereby prevent the fouling of the outgoing run of the trimmer chain with the inner ingoing run thereof under extreme take up conditions.

While I have herein shown and described one form in which the invention may be embodied, it may readily be understood that various variations and modifications in the invention may be attained without departing from the spirit and scope of the novel concepts thereof.

I claim as my invention:

1. In a boring type continuous mining machine having a mobile frame,

a main supporting housing supported on said mobile frame and extending in advance thereof,

a pair of transversely spaced rotary boring heads mounted on said main supporting housing on opposite sides of the longitudinal axis of said mobile frame for rotation about parallel axes extending longitudinally of the machine,

drive gearing within said main supporting housing for rotatably driving said rotary boring heads in timed relation with respect to each other,

parallel upper and lower trimmer bars mounted on said main supporting housing behind said rotary boring heads and positionable adjacent the roof and floor of the mine and having corner sprockets at opposite ends thereof disposed outwardly of the axes of rotation of said boring heads,

a single trimmer chain guided for movement along said trimmer bars and about said corner sprockets and positioned by said trimmer bars to trim the roof and fioor of a mine and having spaced vertically extending runs passing from one trimmer bar to the other,

a pair of laterally spaced drive sprockets disposed intermediate said upper and lower trimmer bars and inwardly of the axes of rotation of said boring heads and training said trimmer chain to extend angularly inwardly of said corner sprockets about said drive sprockets into a generally hourglass form and means driven by the drive gearing for driving said boring heads for driving said drive sprockets at the same rates of speed in timed relation with respect to rotation of said boring heads and driving said trimmer chain along said trimmer bars to trim the roof and floor of the mine and dividing the drive loads on said trimmer chain to exert pulling forces on said trimmer chain through each of said trimmer bars.

2. The structure of claim 1,

wherein individual take up arms are pivoted on said main supporting housing for movement about axes coaxial with the axes of rotation of said drive sprockets,

wherein a separate idler is mounted on the end of each take up arm for engagement with a vertical run of said trimmer chain on the outgoing side of the associated drive sprocket,

wherein individual fluid pressure operated cylinders and pistons are operatively connected between said main supporting housing and said arms, and

wherein said cylinders and pistons are connected with a common source of fluid under pressure to maintain equal tension on each vertical run of said trimmer chain.

3. The structure of claim 2,

wherein each take up arm has a bearing pad thereon, spaced from the associated tension idler and on the opposite side of the chain from the tension idler as the chain leaves its drive sprocket,

said bearing pads being engageable with the runs of the chain coming into the associated drive sprockets in extreme take up positions of said tension idlers, to prevent fouling of the outgoing run of the chain with the incoming run of the chain under extreme take up conditions.

References Cited UNITED STATES PATENTS 2,743,093 4/1956 Robbins 299-61 X 2,868,526 1/1959 Jamison et al 29961 X 3,062,519 11/1962 Osgood 29957 X 40 ERNEST R. PURSER, Primary Examiner.

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