Multi-purpose vehicle for use underground

Abstract

A self-propelled vehicle having independently steerable and suspended wheel assemblies for use in underground excavations. The vehicle includes means for temporarily supporting the roof of an excavation, drilling holes in the roof, and inserting bolts therein. The vehicle also includes scoops mounted at each end with a conveyor joining the scoops, thus giving the machine a self-loading capacity. The application also discloses a method for systematically installing roof bolts.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This is a division of U.S. application Ser. No. 299,354, filed Oct. 20, 1972, now U.S. Pat. No. 3,811,290

FIG. 9A is a sectional view taken along line IX--IX of FIG. 9;

At the inboard end of the top portion of trunion 92 is mounted a lower spring housing 200. Lower spring housing 200 is adapted to engage and hold suspension spring 201. A pair of oppositely facing L-shaped rail members 202 are transversely mounted to horizontal support member 205 and extend, preferably, between plate 102 and the outboard side of motor 116. Horizontal support member 205 is, in turn, supported by a pair of upstanding support members 206 which are mounted to frame 6. This particular supporting arrangement for horizontal support member 205 is made necessary by the fact that body 28 and its associated body sections 30 are movable and thus not suitable for supporting the suspension assembly for wheel 106. An upper spring housing 203 is secured to a spring mounting plate 204. Upper spring housing 203 preferably has an interior diameter slightly larger than the outer diameter of housing 200 to permit housing 200 to move within the upper housing 203 during flexing of spring 201. At its upper end, spring 201 is mounted to plate 204. Plate 204 includes a pair of lands for engaging the horizontally inwardly extending lands of rails 202 to permit the upper spring assembly to transversely move along rails 202. This permits the wheel assembly 12 to pivot about pin 96 as described above and yet retain a suspension mounting.

At the outboard end of trunion 92 and along its vertical center line are mounted upper and lower female bearing members 100. A vertical motor mounting plate 102 having a pair of upper and lower male bearing members 104 engaging, respectively, female bearing members 100 is positioned within trunion 92. Plate 102 is, therefore, adapted to pivot about the vertical center line of the respective bearings. Since the wheel 106 is mounted to plate 102, it will also pivot with the plate about a vertical axis.

Each wheel 106 is independently steerable through a total angle of 45°, 22.5° on either side of the transverse axis passing through the center of the wheel. Steering is provided by a pair of hydraulic steering cylinders 108 each pivotally mounted at one end to a mounting bracket 110 affixed to A-frame 88 and at the other end to motor mounting plate 102. Actuation of steering cylinders 108 cause wheel 106 to pivot about a vertical axis within the 45° range indicated by dashed lines in FIG. 8. Suitable hydraulic control valves (not shown) allow for lengthening and shortening of cylinders 108 as wheel 106 moves vertically about its pivotal mounting to frame 4.

Mounting plate 102 is provided with an opening 114. A hydraulic motor 116 is mounted at the inboard side of plate 102. Motor 116 is preferably a low speed, high torque hydraulic motor having s stationary housing or rotating shaft. Motor 116 includes a shaft 118 which passes through opening 114. Wheel 106 includes an annular support hub 120 mounted to shaft 118 by means of bolt 122. Support hub 120 includes an annular land 124 at the inboard end which is adapted to support and position brake disc 126. Support hub 120 also includes an outboard extension to which is mounted a circular wheel mounting member 128. Member 128 is mounted so as to provide the hub with an annular land 130 between the mounting member 128 and the outboard end of the hub. A wheel member 132 having a circumferential rim member 133 is bolted to mounting member 128 by means of bolt 134; wheel member 132 is adapted to be nested upon land 130. A tire 136 is mounted in a conventional manner on rim member 133. Unlike most rubber-tired vehicles used at present in underground mines, tire 136 may be solid rather than pneumatic because the wheel suspension system just described absorbs the forces normally transmitted by solid tires.

Referring now to FIGS. 10-14, chuck assemblies 44 will be described in detail. Chuck assemblies 44 serve a dual purpose in the operation of machine 2; they grip the drill bits necessary to drill holes in the mine roof and they hold the heads of the roof bolts for insertion into the drilled holes. Thus, the chuck itself (shown diagrammatically in FIG. 11 and designated by the reference numeral 138) must be readily adaptable to grip the shank of a drill bit and securely hold the head of a bolt. Chuck 138 is secured to a square horizontal mounting plate 140. Mounted to the bottom of plate 140 by means of bolts 142 is drive means 144 which imparts rotation to chuck 138 through a shaft 146. Drive means 144 may take the form of a hydraulic motor and includes a conventional torque limiting device. Pivotally mounted on the top surface of plate 140 by means of pins 147 are dogs 148. The free end of each dog 148 has a semi-circular slot 150 adapted to embrace a portion of the shank of a workpiece, either a drill bit or roof bolt. As shown in FIG. 10, two dogs 148 are positioned on opposite sides of chuck 138 and when pivoted into place their slots frictionally hold the shank of a workpiece 152 in the vertical position. Additional dogs 148 may be mounted on plate 140 if desired.

Plate 140 has a pair of aligned lugs 154 extending from opposite sides of plate 140 along a centerline thereof. Lugs 154 fit into trunions (not shown) mounted on a square gimbal member 156 positioned in planar relationship with plate 140 and equidistant from its edges. In turn, gimbal member 156 has a pair of aligned lugs 158 extending from opposite sides of gimbal member 156 on a center line of plate 140 which is perpendicular to the center line of lugs 154. Lugs 158 fit into trunions (not shown) mounted on an outer chuck support member 160 also positioned in planar relationship with plate 140 and gimbal member 156 and equidistant from the edges of gimbal member 156. The effect of these two gimbal mountings is to permit mounting plate 140 (and thus chuck 138) to seek the true horizontal regardless of the orientation of chuck support member 160. In this way, a workpiece held in chuck 138 will always assume a vertical position. Chuck assembly 44 is provided with suitable means (not shown) to automatically lock the gimbal mountings when drive means 144 is energized.

Chuck support member 160 is supported by a pair of vertical hydraulic lift cylinders 162 and secured to the piston rods thereof by means of bolts 164. Lift cylinders 162 are of the conventional single-acting type and are secured at their lower ends by means of bolts 165 to brackets 166 depending from body sections 30 on either side of chuck assemblies 44.

Lift cylinders 162 are adapted to raise chuck assembly 44 above the top surface of body 28. To assure smooth upward movement of chuck assembly 44 when lift cylinders 162 are actuated, a pair of vertical guide posts 168 are provided to extend between the bottom of chuck support member 160 and brackets 166 which support lift cylinders 162. Each guide post 168 includes a first L-shaped member 170 depending from its point of attachment at one corner of chuck support member 160 and a second L-shaped member 172 dimensioned to receive first L-shaped member 170 and secured at its lower portion to bracket 166.

As shown in FIG. 1, machine 2 is provided with an electric motor 174 suitably mounted on frame 4. Motor 174 may receive its power from a trailing cable or a battery. In certain instances, it may be preferable to omit electric motor 174 and substitute therefor a diesel engine. Electric motor 174 is used to drive a hydraulic pump 176 by means of a rotating shaft 178. Pump 176 furnishes hydraulic fluid under pressure to drive hydraulic motors 116 and 76.

Referring now to FIGS. 15-20, the operation of machine 2 within an underground coal mine will now be described: As stated above, when the continuous miner withdraws from the face of the mine, it leaves an expanse of unsupported roof above. If the roof is of such composition as to make it particularly susceptible to collapse, vertical timbers may be wedged between the roof and the floor to provide temperaory support while the continuous miner is operating. In any event, government regulations prevent workmen from moving into a room under an unsupported roof to install roof bolts. Accordingly, the machine of the present invention is brought into position at the threshold of the room.

The machine 2 is fitted with four chuck assemblies located in two rows spaced 4 feet apart, with 4 feet between assemblies in each row. The purpose of this arrangement is to comply with the usual government regulation that roof bolts be placed at spaced intervals of 4 feet both longitudinally and transversely. A greater or lesser number of chuck assemblies than four may be employed to suit local conditions.

Government regulations also require that roof bolts be installed within a specified distance from the longitudinal walls of the room. Thus, the first position of machine 2 within the unsupported room will generally be closely adjacent a side wall as shown in FIG. 15. Position 1 shown in the Figure is reached by tramming the machine by remote control into the room, the machine operator being safely situated to the rear under a supported roof. If timbers have been erected, the machine will simply knock them down as it advances; the displaced timbers will be removed after the roof is supported.

Prior to advancing machine 2 into Position 1, lift cylinders 26 and 162 are placed in their retracted (lowermost) positions and drill bits are installed in chuck assemblies 44. As the machine advances to Position 1, the operator remotely actuates the forward scoop 54 to place its lip on the mine floor (see FIG. 16) so that any coal debris in the machine's path is gathered up by the scoop. At the same time, the rear scoop 54 is placed in a raised position. Conveyor 62 is also actuated so that when the coal debris gathered by the forward scoop is pushed rearwardly by the advance of machine 2, it falls onto conveyor 62 and is carried to rear scoop 54 and deposited therein. Thus, the combination of the two scoops and the conveyor serves to make machine 2 self-loading and capable of carrying a payload far in excess of a conventional front scoop loading machine. It may be desirable to link the drive means of conveyor 62 with the drive means of the machine to take advantage of the low speed, high torque motor operation provided for in the machine drive means.

When machine 2 reaches Position 1, the operator remotely actuates roof support cylinders 16 to cause them to extend into engagement with the roof and the floor as best shown in FIG. 18. Once roof support cylinders are positioned, the operator is free to move under the roof since it is now supported. With the drill bits already in place in chuck assemblies 44, the operator actuates lift cylinders 26. In unison, lift cylinders 26 extend their associated piston rods 27 upwardly and cause body 28 to lift from its points of support on frame 4. Smooth upward movement of body 28 is assured by the cooperative sliding action of slide posts 46.

As body 28 moves upwardly, it carries with it chuck assemblies 44 and their associated lift cylinders 162. The gimbal-mountings provided in chuck assemblies 44 enable the upwardly moving drill bits to seek the true vertical regardless of the orientation of frame 4. When the drill bits strike the roof, the operator actuates drive means 144 to rotate the drill bits; automatically, the gimbal-mountings on chuck assemblies 44 are locked. Dogs 148 firmly hold the drill bits in place, making any manual steadying or guiding of the drill bits by the operator unnecessary. Thus, the simultaneous drilling of four correctly spaced holes begins.

When piston rods 27 reach the limit of their travel (see FIG. 16), the operator actuates lift cylinders 162 to commence the upward movement of chuck assemblies 44, guided by guide posts 168. The piston rods 182 of lift cylinders 162 extend upwardly to permit the drilling operation to progress. If necessary, the operator can retract chuck assemblies 44 and insert drill bit extensions to obtain the necessary depth in the holes being drilled. One of the advantages of the drilling sequence just described is that it effectively denies the operator any occasion to place his hands near the chuck assemblies 44 during drilling and thereby reduces the possibility of accident and injury.

When holes of correct depth are drilled, chuck assemblies 44 are lowered by bleeding lift cylinders 162. Then body 28 is lowered onto its points of support by frame 4 by bleeding lift cylinders 26. The operator may then remove the drill bits and any extensions thereof from chuck assemblies 44.

The next step is the insertion of roof bolts into the drilled holes. Since the presence of machine 2 beneath the holes usually prevents insertion of straight bolts into the holes, the operator usually will have to bend each bolt manually, get it started into the hole, and bend it back so that the bolt head may be placed in a suitable socket in chuck assembly 44. This operation is shown diagrammatically in FIG. 19. When all bolts are in position and being held in chuck assemblies 44 by dogs 148, the operator again sequentially actuates the lift mechanisms as described above to drive the bolts home. A torque sensing mechanism in each drive means 144 permits the operator to automatically torque each bolt to the correct value.

When the bolts are secure, the operator lowers both lifting mechanisms and replaces the drill bits in chuck assemblies 44 in readiness for the next drilling operation. The operator next retracts roof support cylinders 16 to the position shown in FIG. 16. While standing under the newly supported roof, the operator actuates each pair of steering cylinders 108 on wheel assemblies 12 to cause each wheel to pivot approximately 22.5° to the left (see FIG. 15). The operator trams machine 2 into Position 2 shown in FIG. 15 while operating the scoop and conveyor as before. The entire drilling sequence just described is repeated and the operator then trams machine 2 in the direction indicated by the arrow in FIG. 15 to reach Position 3. For a machine configured with four chuck assemblies spaced on four foot centers, the distance between Position 2 and Position 3 will be 12.0 ft., assuming a 22.5° crab between Position 1 and Position 2. Further movements of machine 2 to complete the bolting pattern may be varied to suit local conditions.

When roof bolting has been completed, machine 2 may be used to complete the scooping up of debris from the room floor in the manner described above. The versatility of the present invention in this regard eliminates the need for a separate scoop machine, and the time required to withdraw a bolting machine and being in a scoop machine. The effect of the combination roof-bolter and scoop of the present invntion is therefore synergistic.

After scooping up debris and loading its rear scoop and conveyor to capacity, machine 2 may be moved to an unloading site at the rear of the mine without being turned around. The unloading of machine 2 usually may be accomplished by lowering the rear scoop into a bin and actuating conveyor 62. If necessary, however, the pair of roof support cylinders 16 at the front of the machine may be actuated sufficiently to tilt conveyor 62 toward the unloading bin as shown in FIG. 20.

Claims

1. A self-propelled vehicle for use in underground excavations having a floor and a ceiling, said vehicle comprising:

a frame;

wheel assemblies supporting said frame, said wheel assemblies being independently suspended and steerable;

a body supported on said frame;

first lifting means supported by said frame for raising said body above said frame;

a plurality of rotatable chuck assemblies disposed within said body and adapted to engage a workpiece for insertion into said ceiling;

second lifting means supported by said body and engaging said chuck assemblies for raising said chuck assemblies above said body;

a pair of movable scoop containers mounted on said frame at opposite ends thereof;

a reversible conveyor supported by said frame and positioned to transport material from one of said containers to the other; and

means mounted on said frame for contacting said ceiling above said vehicle and said floor below to support said ceiling against collapse.