GB2123879A

GB2123879A - Excavating machines

Info

Publication number: GB2123879A
Application number: GB08221342A
Authority: GB
Inventors: David Garner; Terence Oven
Original assignee: Coal Industry Patents Ltd
Current assignee: Coal Industry Patents Ltd
Priority date: 1982-07-23
Filing date: 1982-07-23
Publication date: 1984-02-08

Abstract

An excavating machine (1) for forming an underground roadway (2) comprises a mobile base (3) and an articulated boom assembly (10) pivotally mounted on the base. The main pivot shaft (14) for the boom assembly is supported in bearings (16, 17) provided on both sides of the boom assembly's connection with the pivot shaft. <IMAGE>

Description

SPECIFICATION Excavating machines The invention relates to excavating machines for forming underground roadways.

In particular, although not exclusively, the present invention relates to an excavating machine for forming underground roadways in an underground mine.

It is known for such excavating machines to comprise a mobile base and a forwardly extending rotary cutter carrying boom pivotally mounted on the base. Unfortunately, such known machineconstructionstend notto be suitable for excavating relatively hard rockfrom the working face.

It has been proposed to use a rigid boom mounted on the base for pivotal movement about a substantially horizontal axis. Unfortunately, such a machine tends not to be suitableforexcavating rock to form a flat mine floor across the roadway.

An object of the present invention is to provide an excavating machine which tends to overcome or reducethe above mentioned problems encountered with prior known machines.

According to the present invention an excavating machine for forming an underground roadway com- prises a mobile base and a cutter carrying boom assembly pivotally mounted on the base, the cutter carrying boom assembly comprising two articulatedly connected boom components, one boom component being drivably mounted on a main shaft provided with a drive for pivoting the shaft to and fro about an axis substantially parallel to the longitudinal axis ofthe roadway, the shaft being mounted in bearings mounted on the base and located on both sides of the said one connection of the said one boom component with the shaft, the other boom component being pivotally supported by said one boom componentfor rotary motion about an axis substantially parallel to the longitudinal axis of the roadway, said other boom component providing a rotary mounting meansfora cutter head, the rotary driveforthe cutter head extending via gearing supported by the boom assemblyfrom a drive motor mounted on the base.

Preferably, the rotary drive for the cutter head comprises a main drive shaft extending co-axially within said main shaft. and gearing mounted within the boom components.

Preferably, said other boom component is articulated with respect to said one boom component by drive gearing carried by the boom assembly.

Advantageously,the drive gearing for articulating the said other boom component comprises an externally mounted gearwheel and a hydraulic motor drivablyconnected to the externally mounted gear wheel via further gearing.

Conveniently, said further gearing is housed within a gearbox mounted externally of the boom components.

Preferably, an abutment pad is provided on the base for engagement by said other boom component.

By way of example, one embodiment ofthe present invention will be described with reference to the accompanying drawings, in which Figure lisa side elevation of an excavating machine constructed in accordance with the present invention; Figure 2 is a plan of Figure 1; and Figure 3 is an incomplete partiy sectioned view of a detail of Figure 1.

Figures 1 and 2 show the excavating machine 1 in an operational position situated in an elongate roadway 2 in an underground mine. The machine comprises a crawler track mounted base 3 provided with a conveyor4forconveying cut rock or mineral from the working face Sat the head ofthe roadway and control equipment6forcontrolling operation ofthe machine as discussed later in the specification.

The machine also comprises a rotary cutter carrying means comprising a boom assembly 10 pivotally mounted on the base and supporting a rotary cutter head 11 having cutter picks (not shown) for excavating rock in mineral from the working face to extend the roadway. In Figures 1 and 2 the rotary cutter head is shown sumped-in to the working face at mine floor level.

The boom assembly 10 comprises two articulatedly connected boom components 12 and 13, one component 12 ofwhich isdnvably mounted on a hollow, main shaft 14 (see particularly Figure 3) provided with a drive for pivoting the shaftto and fro about its axis 14 substantially co-axial with the roadway's longitudinal axis. The main shaft 14 is rotatably mounted in two bearings 16 and 17 mounted on the base 3. The bearings 16 and 17 are located on opposite sides of the boom component'sconnectionwiththeshafttending to provide a strong construction suitableforwithstanding re-action forces generated when the machine is excavating relatively hard rock.The main shaft 14 is drivably connected to a drive gearwheel 18 housed in a gearbox 19 and drivablyengaged buy a pair of gearwheels (not shown) drivably mounted on the output shafts oftwo hydraulic motors 20 and 21 (see particularly Figure 2). Simultaneous operation ofthe two drive motors causes the main shaft and thereby the boom component 12 to pivot about the axis 15 first in one direction and then in the opposite direction. In the construction shown in the accompanying Figures, the total maximum pivotal movementisabout 180 .

The end of the boom component 12 remote from the main shaft 14 is provided with a rotary mounting 22 for the other boom component 13, the rotary mounting defining a bell shaped housing carrying two bearings 23,24 for rotatably supporting a tapered tubular projection 25 fixedly connected to the boom component 13. The projection 25 is provided with an external drive gearwheel 26 drivably engaged by a gearwheel 27 mounted on the output shaft a hydraulic motor 28, the gearwheel 27 being housed in a gearbox 29 mounted externally ofthe boom components.

In use, the motor 28 drives the gearing 27,26 such thatthe boom component 13 is rotated through 360 in either direction of rotation about the axis 30 which is substantially parallel to the aforementioned axis 15 and to the longitudinal axis ofthe roadway.

The end ofthe boom component 13 remote from the pivotal mounting 22 is provided with an output drive shaft31 drivablysupporting the rotary cutter head 11.

As seen in Figure 3, the shaft 31 drivably connects with epicylic gearing 32 to reducethe rotational speed of the cutter head. The shaft 31 is driven by an electric motor 33 mounted on the base 3, the drive being transmitted via gears 34,35 and 36to a drive shaft 37 and hence via a flexible coupling 38 to shaft 39. The drive then is carried along and within the boom component 12through gearing 40to a connecting shaft41 drivably connected to further gearing 42 provided within the boom component 13, the gearing 42 being drivably connected to the cutter carrying shaft 31. Thus, the motor 33 drives the cutter head 11 independently ofthe respective positions of the boom components 12,13. The rotational speed of the cutter head can be varied by suitably changing the gear wheels 34,35.

The leading edge ofthe base 3 has an abutment pad 44 (see Figure 1) arranged to engage the rearface of the boom component 13tosupportthe boom component during the time the cutter head is being sumped into the working face i.e. into the position as indicated in Figures 1 and 2.

In operation, the machine is advanced along its mobile base until the cutter head is sumped fully into the working face, the articulated boom components being fully folded such that the cutter head is located adjacent to the mine floor and substantially in the centre of the roadway. With the cutter head in this position the boom component 13 is abutting the abutment pad 44. Thus during the sumping-in operation the re-action forces tending to push the rotating cutter head out ofthe working face substantially are taken bythe abutment pad. Once the cutter head is fullysumped into the working face the operator simultaneously controls the drive motors 20 and 28 such thatthe cutter head is traversed across the whole of the working face to extend the roadway.First the cutter is moved to and fro substantially horizontally across the working face to form the mine floor. Then with the cutter head located adjacent one corner of the minefloorthe motors 20 are activated to swing the cutterfully around the curved outer profile of the roadway. Finally the boom component 13 is articulated about the axis 30 underthe control ofthe motor 28to remove any remaining material.

An arch beam roof support then is set to support the newly exposed mine roof.

The machine is advanced until the cutter head is again sumped into the working face and the whole cutting operation repeated.

From the above description it will be appreciated thatthe present invention provides a robust and relatively simple machine capable of excavating the whole working face to extend an underground mine roadway.

In other embodiments of the invention the boom assembly is advanceable relatively to the base. In still other embodiments the pivotal mounting 22,25 including the shaft 41 is telescopic permitting the cutter head to be advanced relatively to the base.

Claims

1. An excavating machine for forming an underground roadway, comprises a mobile base and a cutter carrying boom assembly pivotally mounted on the base, the cutter carrying boom assembly comprising two articulatedly connected boom components, one boom component being drivably mounted on a main shaft provided with a drive for pivoting the shaft to and fro about an axis substantially parallel to the longitudinal axis of the roadway, the shaft being mounted in bearings mounted on the base and located on both sides of the connection ofthe said one boom componentwith the shaft, the other boom component being pivotally supported by said one boom componentforrotarymotion about an axis substantially parallel to the roadway's longitudinal axis, said other boom component providing a rotary mounting means for a cutter head, the rotary drive for the cutter head extending via gearing supported by the boom assembly from a drive motor mounted on the base.

2. A machine as claimed in claim 1, in which the rotary drive for the cutter head comprises a main drive shaft extending coaxiallywithin said main shaft, and gearing mounted within the boom components.

3. A machine as claimed in claim 1 or2,inwhich said other boom component is articulated with respecttosaid one boom component by drive gearing carried by the boom assembly.

4. A machine as claimed in claim 3, in which the drive gearing for articulating the said other boom component comprises an externally mounted gear wheel and a hydraulic motor drivably connected to the externally mounted gearwheel via further gearing.

5. A machine as claimed in claim 4, in which said further gearing is housed within a gearbox mounted externally ofthe boom components.

6. A machine as claimed in any one ofthe preceding claims, in which an abutment pad is provided on the base for engagement by said other boom component.

7. An excavating machine for forming an underground roadway, substantially as described herein and substantially as shown in the accompanying drawings.