GB2186012A - A tunnelling machine - Google Patents

Abstract

A tunnelling machine (2) comprises a drum cutter (13) having a vertically adjustable cutting drum (14). The drum cutter (13) is movable across the width of the tunnel road on a vertically adjustable guide frame (22) extending transversely to the road length and is mounted together with the guide frame (22) on endless track assemblies (3) movable lengthwise of the road. The guide frame (22) is supported on a tilting frame (20) and overhangs the track assemblies (3) at the front end. The tilting frame (20) can pivot about a transverse pivot (21) positioned at the rear end of the machine above the tracks (3) and is so arranged that it can be lowered between the tracks. Double-acting fluid pressure rams (23) act between the machine chassis (4) and the tilting frame (20) at a distance from the pivot (21) and provide for vertical adjustment of the frame. Scraper chain conveyors (5) for spoil removal are similarly positioned below the frame (20) and can also pivot downwards between the two tracks <IMAGE>

Description

SPECIFICATION Atunnelling machine This invention relatestoatunnelling machine of the type having a drum cutter which has a verticallyadjustable cutting drum and is movable across the width ofthetunnel or road being excavated on avertically adjustable guide frame which extends transversely across the road length and is mountedtogetherwith the frame on caterpillar tracks movable lengthwise of the road.

Existing machines of this type suffer from a number of limitations and disadvantages. For example, some such machines are of use more particularlyfor cutting thin seams or driving relatively smali tunnel roads and cannot be used effectively in thick seams orto drive wide roads. It is an object of the invention to provide an improved tunnelling machine of the stated type which will be of wider use and application.

Broadly stated, the invention consists in a tunnelling machine comprising a drum cutterwhich is movable across the width of the tunnel road being excavated on a vertically adjustable guide frame extending transversely across the road and mounted on caterpillar (R.T.M) track assemblies movable lengthwise of the road, and a cutter drum arranged to engage the heading face and mounted on a pivoted support arm whose pivotal axis extends parallel with the drum axis towards the face, and in which the guide frame has atop guide bar and a bottom toothed rackwhich support, guide and provide for movement of the drum cutter, and the guide frame is positioned at the front end of a tilting frame whose rear end is pivotally supported on the machine chas sisbya pivotwhich extendstransverselyacrossthe road length and is spaced above the road floor by not morethantheradiusofthedrum.

Thetilting frame enablesthe guideframe and the cutter to be adjusted over a relatively wide vertical range. Consequently, a machine of this kind can be used if necessary to drive relatively wide-section roads and thus has a wide range of possible uses going beyond those which can be provided by drum cutters suitable onlyfor use in thin seams orfordriving narrow-section roads. A noteworthyfeature is the ability of the machine to drive curved road crosssections even in relatively hard mineral, sincethe drum cutter can provide the driving power necessary forthis purpose, and can guide the cutting drum arcuately on the roof of the road.Also, the construction ofthe apparatus according to the invention is such as to permit the use of a standard seriesproduced drum cutter such as is used,forexample, to drive a large-rise heading.

According to a preferred feature of the invention the machine includes a scraper chain conveyor for spoil removal resting on a ramp plate between the two caterpillartrack assemblies, the plate being mounted below the tilting frame with its end remote from the heading face supported on a transverse pivot, the opposite end of the ramp plate being connected to double-acting pressure cylinders which provide for vertical adjustment thereof. This arrangement improves the mobility of the machine particularly when it needs to be transported to a different workplace, and also enables the spoil-receiving con veyorto adapt its level in the dirt-pick up zone to the pattern of the road floor.

The invention may be performed in various ways and one specific embodiment will now be described by way of example with reference to the accompanying drawings, in which: Figure lisa diagrammatic side elevation of a tunnelling machine according to the invention, and Figure2 is a plan view of the machine.

In this illustrated example a tunnelling machine 2 is opening up a road 1. The machine 2 comprises two caterpillartrack assemblies 3 interconnected by a running frame 4. Two scraper chain conveyors 5,6 positioned below the frame 4 rise upwards on an incline towards the rear. Immediately in front of the heading face 7 the conveyors 5,6 bend at right- angles in opposite directions to one another and extend to the respective side wall of the road. The two conveyors 5,6are mounted on a ramp plate8which is located between the two caterpillar assemblies 3.

The conveyors 5,6 are driven by a common drive (not shown) positioned near the discharge end of the conveyors. The two conveyors 5,6 can be vertically adjusted at their feed ends and if necessary lowered below the level ofthe road floor 11 by means ofthe plate 8, which is arranged to tilt between the two cat erpillar assemblies 3 on pivots 9 which extend transverse to the length of the road, as shown in Figure 1.

This vertical adjustment is effected by means oftwo double-acting pressure cylinders 10 positioned at the ends of the caterpillar assemblies 3 remote from the pivots 9. A ramp 12 attached to the forward end of the two conveyors 5,6 adjacent the face 7 extends overthewhole width of the road and helps to improve dirttake-up.

Thewinning partofthemachine2comprisesa drum cutter 13 incorporating a cutting drum 14 mounted for rotation at the end of an adjustable support arm 15. The drum 14 has on its peripherya number of helical "whorls" orflanges 16forfeeding material cut out by the cutting tools 17 onto one of the two conveyors 5, 6. The arm 15 is pivotable about a pivot 19 which extends parailel with the rotational axis 18 ofthe drum 14, is fixed with respect to the casing of the cutter 13 and extends lengthwise ofthe road. A driving motor (not shown) is mounted in the said casting and provides the driving motion for the drum 14. This motor also provides the powerfor advancing the cutter 13 and pivoting the arm 15, whose pivotal angle is at least 3600. The rotational axis 18 of the drum 14 and the pivot 19 of the arm 15 are spaced apart from one another by a distance approximately corresponding to drum radius. Consequently, the range of operation of the drum 14 is by its very nature limited. The limited range of operation is increased firstly in the horizontal direction by the distance the cutter 13 can travel across the road width and secondly, in the vertical direction, bytheframe 20 which is mounted at its rear end for pivotal move mentabouta pivot 21 on the frame 4, the pivot 21 extending transversely to road length.At its forward end near the face 7 the frame 20 carries a guide frame 22which acts to support and guide the cutter 13 and which can be adjusted vertically by means ofthe frame 20. The adjusting movement is controlled by two double-acting pressure cylinders 23 pivotally mounted on the running frame 4and having piston rods pivotally connected by horizontal pivots 24to lugs 25 on the frame 20 very close to the frame 22.

The guide frame 22 has at its lower edge a toothed bottom rack 26 whose teeth are engaged by a driving wheel (notshown) of the haulage box of the cutter 13. The cutter chassis rests on the rack 26 and is gui- ded for longitudinal movement by guide shoes 27 which engage around the rack cross-section. Atthe upper part ofthe cutter lugs 28 or the equivalenten- gage around a tubular guide bar or rail 29 positioned atthe top edge of a metal plate 30 forming part of the frame 22, the plate 30 being connected to the frame 20 and braced by ribs 31.

Claims (3)

1. Atunnelling machine comprising a drum cutterwhich is movable across the width of the tunnel road being excavated on a vertically adjustable guide frame extending transversely across the road and mounted on caterpillartrackassemblies movable lengthwise of the road, and a cutter drum arranged to engage the heading face and mounted on a pivoted support arm whose pivotal axis extends parallel with the drum axis towardsthe face, and in whichtheguideframe has atop guide bar and a bottom toothed rackwhich support, guide and provide for movement of the drum cutter, and the guide frame is positioned atthe front end of a tilting frame whose rear end is pivotally supported on the machine chassis buy a pivot which extends trans verselyacrossthe road length and is spaced above the road floor by not more than the radius of the drum.

2. A machine according to claim 1, including a scraper chain conveyor for spoil removal resting on a ramp plate between the two caterpillartrack assemblies the plate being mounted below the tilting frame with its end remote from the heading face supported on a transverse pivot, the opposite end of the ramp plate being connected to double-acting pressure cylinders which provideforvertical adjustment thereof.

3. Atunnelling machine substantially as described with reference to the accompanying drawings.