A mining machine and a method for rock excavation

Abstract

A mining machine (102) for rock excavation, comprising: a rotatable cutting head (104) having cutting elements (108); a holder (110) for holding the cutting head (104); a movable thrust unit (112) attached to the holder (110); a machine body (114) attached to the thrust unit (112); a thrust apparatus (118) for moving the thrust unit (112) between retracted and extended positions and for pushing the thrust unit (112) forward, thereby pushing the cutting elements (108) into a rock formation; a hydraulic pump (122); a hydraulic consumer (125); and a hydraulic line system (126) for connecting the hydraulic pump (122) to the hydraulic consumer (125). The hydraulic line system (126) comprises first hydraulic lines (126a) attached to the machine body (114), second hydraulic lines (126b) attached to the thrust unit (112), and two telescopic hydraulic line units (128). Each telescopic hydraulic line unit (128) connects one (126a) of the first hydraulic lines (126a) to one (126b) of the second hydraulic lines (126b). The telescopic hydraulic line unit (128) is retracted and extended with the movement of the thrust unit (112).

1 . A mining machine for rock excavation, the mining machine comprising a machine body, a rotatable cutting head, a holder for holding the rotatable cutting head, a thrust unit attached to the holder, and a thrust apparatus for moving the thrust unit in relation to the machine body; the mining machine further comprising:
 a hydraulic pump, one or more hydraulic consumers, and   a hydraulic line system for hydraulically connecting the hydraulic pump to the hydraulic consumer, wherein the hydraulic line system comprises two telescopic hydraulic line units, wherein each telescopic hydraulic line unit hydraulically connects one of first hydraulic lines attached to the machine body to one of second hydraulic lines attached to the thrust unit,   
       characterized in,
 that each telescopic hydraulic line unit comprises a first tube and a second tube movable in relation to one another, wherein the first tube is configured to telescope into the second tube, and wherein one of the first and second tubes is attached to the machine body and the other one of the first and second tubes is attached to the thrust unit, and 
 that the mining machine is configured to move the thrust unit and the cutting head back and forth in cutting strokes to cut the rock formation, thereby retracting and extending the telescopic hydraulic line unit with the movement of the thrust unit. 
 
     
     
         2 . A mining machine according to  claim 1 ,
 the mining machine being configured to rotate the cutting head in relation to the holder,   the holder being configured to hold the cutting head between the machine body and a rock formation to be excavated,   the rotatable cutting head having an outer circumferential surface and with a plurality of rock-engaging cutting elements distributed on the outer circumferential surface, the outer circumferential surface having a width which constitutes the rock cutting width of the cutting head, and   the thrust unit being movable in relation to the machine body between a retracted position and an extended position, the thrust apparatus being configured to push the thrust unit in a forward direction, thereby pushing the cutting elements into the rock formation.   
     
     
         3 . A mining machine according  claim 2 , wherein each telescopic hydraulic line unit forms a hydraulic channel, wherein each hydraulic channel is hydraulically connected to the one of first hydraulic lines by means of a first hydraulic block having hydraulic channels, and wherein each hydraulic channel is hydraulically connected to the one of second hydraulic lines by means of a second hydraulic block having hydraulic channels. 
     
     
         4 . A mining machine according to  claim 1 , wherein the mining machine comprises one or more propelling units for propelling the mining machine, and wherein the propelling unit is configured to rest on a floor of a tunnel during the rock excavation. 
     
     
         5 . A mining machine according to  claim 1 , wherein the mining machine comprises one or more first stabilizing units movable in relation to the machine body, and wherein the first stabilizing unit is configured to engage a roof of the tunnel to secure the mining machine and counteract forces created during the rock excavation. 
     
     
         6 . A mining machine according  claim 5 , wherein the mining machine comprises one or more second stabilizing units movable in relation to the machine body and configured to engage a floor of the tunnel to secure the mining machine and counteract forces created during the rock excavation. 
     
     
         7 . A mining machine according to  claim 5 , wherein at least one of the first stabilizing unit and the second stabilizing unit is attached to the machine body. 
     
     
         8 . A mining machine according to  claim 1 , wherein the hydraulic consumer or one of the hydraulic consumers is attached to the cutting head. 
     
     
         9 . A mining machine according to  claim 1 , wherein the hydraulic consumer or one of the hydraulic consumers is attached to the holder. 
     
     
         10 . A mining machine according to  claim 1 , wherein the mining machine comprises one or more hydraulic motors for rotating the cutting head in relation to the holder, the hydraulic motor comprising the hydraulic consumer or one of the hydraulic consumers. 
     
     
         11 . A mining machine according to  claim 1 , wherein the hydraulic consumer or one of the hydraulic consumers is attached to the thrust unit. 
     
     
         12 . A mining machine according to  claim 1 , wherein the mining machine comprises one or more guide apparatuses for guiding the thrust unit in relation to the machine body between the retracted position and the extended position, each guide apparatus comprising a guide. 
     
     
         13 . A mining machine according to  claim 12 , wherein the guide is substantially linear, and wherein the guide apparatus is configured to linearly move the thrust unit in relation to the machine body between the retracted position and the extended position. 
     
     
         14 . A mining machine according to  claim 1 , wherein the holder is movable in relation to the thrust unit, wherein the mining machine comprises a positioning apparatus for moving and positioning the holder and the cutting head in relation to the thrust unit in a horizontal direction and/or a vertical direction when the propelling unit rests on the floor of the tunnel. 
     
     
         15 . A mining machine according to  claim 1 , wherein each cutting element comprises a disc-shaped cutter, wherein the cutting head comprises a cutting head frame having a cutter seat for each cutter, and wherein the cutter is seated in the cutter seat and is rotatable in relation to the cutting head frame. 
     
     
         16 . A mining machine according to  claim 1 , wherein the cutting head has a first side between the outer circumferential surface and an axis of rotation of the cutting head and a second side between the outer circumferential surface and the axis of rotation of the cutting head, wherein the holder comprises a first arm extending at least partly along the first side and holding the cutting head, whereas the second side of the cutting head is without any such arm. 
     
     
         17 . A mining machine according to  claim 1 , wherein the hydraulic pump is attached to the machine body. 
     
     
         18 . A mining machine according to  claim 1 , wherein the mining machine comprises a first part and a second part, wherein the first part comprises the cutting head, the holder, the thrust unit and the machine body, wherein the second part comprises the hydraulic pump, and wherein the first and second parts are connectable to one another. 
     
     
         19 . A mining machine according to  claim 18 , wherein at least one of the first and second the stabilizing units is configured to secure the first part to counteract forces on the first part created during the rock excavation. 
     
     
         20 . A mining machine according to  claim 18 , wherein the second part comprises control equipment for controlling the mining machine. 
     
     
         21 . A mining machine according to  claim 18 , wherein the mining machine comprises an operator cabin attached to the second part of the mining machine, and wherein the mining machine is controllable from the operator cabin. 
     
     
         22 . A mining machine according to  claim 1 , wherein the mining machine is controllable from a remote location. 
     
     
         23 . A mining machine according to  claim 1 , wherein the mining machine is configured to operate at least partly autonomously. 
     
     
         24 . A method for conveying hydraulic fluid to and from a hydraulic consumer with the aid of a mining machine comprising a machine body, a rotatable cutting head, a holder for holding the rotatable cutting head, a thrust unit attached to the holder, a thrust apparatus for moving the thrust unit in relation to the machine body, wherein a hydraulic line system comprising two telescopic hydraulic line units is comprised in the mining machine, of which each telescopic hydraulic line unit hydraulically connects one of first hydraulic lines attached to the machine body to one of second hydraulic lines attached to the thrust unit and wherein each telescopic hydraulic line unit comprises a first tube and a second tube movable in relation to one another, wherein the first tube is configured to telescope into the second tube, wherein the method comprises:
 conveying hydraulic fluid from a hydraulic pump to the hydraulic consumer by means of the hydraulic line system and the telescopic hydraulic line units; and   conveying hydraulic fluid from the hydraulic consumer to the hydraulic pump by means of the hydraulic line system and the telescopic hydraulic line units.   
     
     
         25 . A method for rock excavation with the aid of a mining machine comprising: a machine body, a rotatable cutting head, a holder for holding the rotatable cutting head, a thrust unit attached to the holder, a thrust apparatus for moving the thrust unit in relation to the machine body, wherein a hydraulic line system comprising two telescopic hydraulic line units is comprised in the mining machine, of which each telescopic hydraulic line unit hydraulically connects one of first hydraulic lines attached to the machine body to one of second hydraulic lines attached to the thrust unit and wherein each telescopic hydraulic line unit comprises a first tube and a second tube movable in relation to one another, wherein the first tube is configured to telescope into the second tube, wherein the method comprises:
 pushing the thrust unit in a forward direction by means of the thrust apparatus, thereby pushing cutting elements of a cutting head into the rock formation;   conveying hydraulic fluid from a hydraulic pump to a hydraulic consumer of the mining machine, which hydraulic consumer is a hydraulic motor for rotating the cutting head in relation to the holder, by means of the hydraulic line system and the telescopic hydraulic line units;   conveying hydraulic fluid from the hydraulic consumer to the hydraulic pump by means of the hydraulic line system and the telescopic hydraulic line units; and   rotating the cutting head by means of the hydraulic motor.