US2945686A

US2945686A - Mining machine having means for cutting side wall holes for roof timbers

Info

Publication number: US2945686A
Application number: US623915A
Authority: US
Inventors: Sterling C Moon
Original assignee: Jeffrey Manufacturing Co
Current assignee: Jeffrey Manufacturing Co
Priority date: 1956-11-23
Filing date: 1956-11-23
Publication date: 1960-07-19
Anticipated expiration: 1977-07-19

Description

July 19, 1960 s. c. MOON MINING MACHINE HAVING MEANS FOR CUTTING SIDE WALL HOLES FOR ROOF TIMBERS 4 Sheets-Sheet 1 Filed Nov. 23, 1956 NW 1 NE INVENTOR,

sTERLiNG C. MOON, BY

HTT'Y July 19, 1960 s. c. MOON 2,

- MINING MACHINE HAVING MEANS FOR CUTTING SIDE WALL HOLES FOR ROOF TIMBERS Filed Nov. 23, 1956 4 Sheets-Sheet 2 INVENTOR, '5TERUNG C. MOON, 55

W El 8 3 55 Q H-r'rx July 19, 1960 C. MOON MINING MACHINE HAVING MEANS FOR CUTTING v SIDE WALL HOLES FOR ROOF TIMBERS Filed Nov. 25. 1956 4 Sheets-Sheet ,3

w mo M C m G m L R E T 5 July 19, 1960 s. c. MOON mums MACHINE mwmc MEANS FOR cumuc SIDE WALL HOLES FOR ROOF TIMBERS Filed NOV. 25, 1956 4 Sheets-Sheet 4 INVENTOR, sTElQLJNG C. MOON, w M

. fiTT Y United States Patent MINING MACHINE HAVING MEANS FOR CUT- TING SIDE WALL HOLES FOR ROOF TIMBERS Sterling C. Moon, Dublin, Ohio, assignor to The Jeffrey Manufacturing Company, a corporation of Ohio Filed Nov. 23, 1956, Ser. No. 623,915

10 Claims. (Cl. 262-7) This invention relates to mining machines, and more particularly to a mining machine which includes laterally directed cutting means for cutting into the side walls of the mine to form holes therein for the reception of timbers which span the roof of the mine and support the roof to prevent the collapse thereof.

It is the prime object of the instant invention to provide an improved mining machine which includes laterally directed cutting means adapted to be fed into the side walls of the mine for cutting holes therein, for the placement of roof supporting timbers which span the roof of the mine.

It is a further object of the instant invention to provide an improved mining machine which includes laterally directed cutting means adapted to=be progressively fed into the side walls of the mine as the machine continuously advances during the mining operation, to form holes in the side walls for the reception of roof supporting timbers spanning the mine roof.

It is another object of the instant invention to provide an improved mining machine including a digging head at the front end of the machine, which is vertically adjustable and provides a support for a laterally directed cutting means which is thereby adjusted with the coal digging head, and in which the laterally directed cutting means is adapted to cut into the side walls of the mine adjacent the roof to provide holes in the side walls for the reception of roof supporting timbers.

Still another object of the instant invention is to provide an improved mining machine which includes a digging head at the front end of the machine provided with digging means adapted to cut into the mine face in an area extending beyond the sectional perimeter of the machine to form a tunnel substantially larger than the machine, and further includes laterally directed cutting means supported on the digging head within the perimeter of the machine with means for vertically adjusting the laterally directed cutting means and for feeding the laterally, directed cutting means beyond the perimeter of the machine, to form holes in the side walls of the mine immediately below the roof thereof for the reception of roof supporting timbers which span the mine room.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings:

Fig. l is a side elevational view of a mining machine embodying the instant invention;

Fig. 2 is a top plan View of the mining machine illustrated in Fig. 1;

Fig. 3 is an enlarged side elevational view of the front end of the mining machine shown in Fig. 1;

Fig. 4 is an enlarged top plan view of the front end of the mining machine shown in Fig. 1;

Fig. 5 is a partial plan view in section of certain oper- "ice ating elements of the laterally directed cutting means of this invention;

Fig. 6 is an elevational view partially in section of the laterally directed cutting means of this invention, with the cutting means shown in elevated position; and

Fig. 7 is a sectional view taken on the line 7-7 in Fig. 6.

The instant invention is illustrated in the drawings as embodied in a continuous mining machine 10, which includes a main frame 11 serving as a support for the various operating elements of the machine. Endless traction means 12 of a conventional form are provided on either side of the machine and serve to propel the machine during the transportation thereof and during the mining operation. At the front end of the mining machine 10 there is provided digging means 13, which will be described in greater detail hereinafter. Immediately below the digging means 13 there is a dozer blade 14, which is placed on the floor of the mine and is adapted to scrape therealong, and also forms a slide for the mined material to move up on to the endless chain conveyor 15, which extends longitudinally of the mining machine 10 from immediately below the digging means 13 to a boom 16 at the rear of the machine from which the coal, or other material that is mined, is discharged to shuttle cars, a conveyor belt or other means for removing the material from the mining site.

The main frame 11 is provided with a forwardly extending support frame 17 which is pivotally mounted on the forward end of the main frame 11 by pivot means 18. The support frame 17 carries the dozer blade 14 at its forwardmost end and also forms a support for the endless chain conveyor 15 which is entrained on the support frame 17. The support frame 17 also supports the digging means 13, which is pivotally secured thereto by pins 19.

v The digging means 13 comprises a lower digging head 22 and an upper digging head 23, placed one directly above the other. Each of the digging heads includes a plurality of forwardly extending shafts 24 each of which carries, at its forward end, a radially extending digging arm 25 extending to one side of the shaft so as to be eccentrically mounted thereon. Each of the digging arms 25 is provided with sets of forwardly directed cutting bits 26 which, during the rotation of the shafts 24 and the digging arms 25, cut into the mine face to dig the coal or other material therefrom.

Since the digging arms 25 extend to only one side of the shafts 24, the cutting bits 26, carried by the digging arms 25, will operate eccentrically and those cutting bits 26 located adjacent the perimeter of the mining machine 10 will cut on an area of the mineface that extends a substantial distance beyond the sectional perimeter of the mining machine 10. The digging means 13 thereby cuts a tunnel in the mine which is substantially larger thanthe sectional dimensions of the mining machine 10, thereby permitting free passage of the mining machine 10 in the tunnel thus cut. At such time as the mining machine 10 is merely traveling in the tunnel formed by the digging means 1 3 without performing any mining operation, the digging arms 25 are rotated to such positions that they are placed within the sectional perimeter of the machine 10 out of contact with the walls of the tunnel. Referring to Figs. I and 2, it is seen that the cutting bits 26 on the digging head 23 extend substantially above the top of the mining machine 10, and that the cutting bits 26 at the sides of the machine 10 extend substantially beyond the sides to achieve the aforementioned result of cutting a tunnel in the mine that is substantially larger than the sectional dimensions of the machine. 7

The upper and

lower digging heads

22, 23 are driven from a pair of motors 27, supported on the main frame 11 behind the

digging heads

22, 23. The armature shafts of the motors 27 connect to gearing contained within a gear casing 28 from which there extends a pair of shafts 29. These shafts 29 are connected to drive shafts 30 by universal joint means 31. The drive shafts 30 are inclined downwardly from the gear casing 28 and are connected at their lower ends to driven shafts 32 through universal joints 33. Each of the drive shafts 30 includes a shear pin coupling 34 which yields when the drive shaft 30 is subjected to an excessive load, and a telescoping section 35 which may be extended or contracted when the

digging heads

22, 23 are adjusted as described hereinafter. Each of the digging heads has secured to the rear wall thereof a gear box 36 to which the driven shaft 32 is connected and it is from the gearing contained within the gear boxes 36 that the digging means 13 is driven. It will be understood that the gearing rotates the digging arms 25 in a predetermined order so that they will always clear one another in the course of their rotation. Since the digging arms 25 on the upper digging head 23 are set back behind the digging arms 25 on the lower digging head 22, it is merely necessary that the rotation of the digging arms 25 in each of the digging heads, be coordinated with the rotation of the digging arms 25 in that digging head, without regard to the digging arms in the other digging head. Accordingly, the drives to the

digging heads

22, 23 are 'mutually independent.

The

digging heads

22, 23 are mounted as a unit on the support frame 17, being connected thereto by pivot pins 19. The

digging heads

22, 23 may be tilted forwardly on the pivot pins 19 to the position 40 in Fig. 3. A hydraulic cylinder and piston mechanism 41 is provided one at each side of the machine for the purpose of tilting the

digging heads

22, 23 forwardly, and the cylinder and piston mechanism 41 is connected to the main frame 11 by a pin 42 and is connected to the

digging heads

22, 23 by a pin 43. Suitable hydraulic control means are provided for expanding and contracting the cylinder and piston 41 to tilt the

digging heads

22, 23 as desired. Forward tilting of

thedigging heads

22, 23 causes the cutting bits 26 on the digging arms 25 to cut downwardly whereby the mining machine 10 will follow a descending path.

The support frame 17, which is attached to the main frame 11 on the pivot means 18, may also be vertically adjusted, and for this purpose there is provided cylinder and piston mechanism 44, one at each side of the machine 10, connected to the main frame by pin 45 and connected to the support frame 17 by pin 46. Suitable hydraulic control means is provided for operating the cylinder and piston mechanism 44 to swing the support frame 17 on its pivot 18 between the

positions

47, 47 as shown in Fig. 3. Adjustment of the support frame 17 also adjusts the position of the

digging heads

22, 23 since these are supported by and carried on the support frame 17. The

digging heads

22, 23 may be adjusted relatively to the support frame 17 to maintain the cutting bits 26 in a vertical plane.

As a further adjustment of the digging means 13 the upper digging head 23 is mounted on the lower digging head 22 for vertical adjustment relatively to the latter to dig on an area of the mine face having a greater height. The upper digging head 23 is provided with a vertical track 48 at each side thereof, which receives a mating guide 49 which is engaged in the track 48 at each side of the

digging heads

22, 23. The upper digging head 23 may be vertically adjusted with respect to the lower digging head 22 by sliding the upper digging head 23 along the guide 49, the vertical tracks 48 in the upper digging head 23 serving to maintain the two digging heads in proper alignment, and the guide 49 guiding the vertical movement of the upper digging head 23. A cylinder and piston mechanism 50 is provided for adjusting the upper digging head 23 with respect to the lower digging head 22, and is connected at its lower end by a pin 51 to the lower digging head 22 and at its upper end by a pin 52 to the upper digging head 23. Suitable hydraulic control means is provided for expanding the cylinder and piston 50 to raise the upper digging head 23 with respect to the lower digging head 22.

Immediately behind the digging heads 22, 23 there is provided a laterally directed cutting means 55 adapted to be fed transversely of the mining machine 10 into the side walls of the mine .to' cut holes therein for the reception of transversely extending timbers or beams, which are placed immediately below the mine roof for the purpose of supporting the roof and preventing its collapse. In Figs. 1 and 2 it is seen that the laterally directed cutting means 55 is located within the sectional perimeter of the machine, and when it is desired to cut the holes in the side walls of the mine the laterally directed cutting means 55 is fed out laterally of the mining machine 10 to either side thereof.

The laterally directed cutting means 55 is carried on the upper digging head 23 and is raised vertically therewith when the upper digging head 23 is adjusted with respect to the lower digging head 22. As seen in Figs. 1 and 2, the digging arms 25 and the. cutting bits 26 cut a substantial distance beyond the laterally directed cutting means in vertical and lateral directions. Accordingly, the roof of the mine will be formed a substantial distance above the laterally directed cutting means 55 and, in order to cut the holes in the side walls of the mine immediately below the roof, it becomes necessary to elevate the laterally directed cutting means 55 to the level of the uppermost cutting bits 26, which will place the cutting means 55 in a position immediately below the roof of the mine. The mechanism for accomplishing this purpose is described hereinafter. When the laterally directed cutting means 55 has been elevated to a position immediately below the roof of the mine, it is then fed laterally into the side Walls to cut the holes therein for the reception of the roof supporting timbers.

The laterally directed cutting means 55 is mounted on the upper digging head 23 by means of a slide frame 56. One such slide frame 56 is provided at either side of the upper digging head 23, and each slide frame 56 independently supports a laterally directed cutting means 55, there being one such laterally directed cutting means 55 on each side of the mining machine 10. In the normal course of operation the laterally directed cutting means 55 on the opposite sides of the machine are both advanced simultaneously in opposite directions to cut holes in the side walls of the mine, in corresponding positions opposite each other for the purpose of placing a timber across the mine roof for supporting the latter.

The slide frame 56 is formed with

guides

57, 58 each of which is received within a vertically extending track 59, 60 respectively, for guiding the movement of the slide frame 56 in a vertical direction relatively to the upper digging head 23. The

guides

57, 58 are formed at the forward ends of

plates

61, 62 respectively, which plates are disposed in vertical planes. To the rear of the

plates

61, 62 there is secured, as by welding or like means, a laterally extending guide 63. The guide 63 is formed with an upper track 64 and a corresponding lower track 65, both said

tracks

64, 65 being disposed horizontally and extending laterally of the mining machine 10. A support 66 for the laterally directed cutting means 55 extends in a lateral direction behind the guide 63, and is formed with guide lugs 67 which engage in the

tracks

64, 65 of the guide 63. four guide lugs 67, two of which engage with each of the

tracks

64, 65. It is thus seen that the support 66 is adapted to slide on the guide 63 from a position in which the support 66 and the cutting means 55 carried thereon is positioned within the perimeter of the mining machine 10 to a position in which the cutting means 55 is disposed in a position extending beyond the perimeter of the min,

The support 66 is formed with ing machine, whereby the cutting means 55 is operative to cut into the side wall of the mine.

The laterally directed cutting means 55 comprises a cutter bar 70 which is secured to the support 66 by a plurality of bolts 71, which in the present embodiment of the invention, number four. The cutter bar 70 provides a track 72 within which there is placed an endless cutter chain 73, the links of which comprise sockets 74 for the reception of cutting bits 75, each of which is secured within a socket 74 by means of a bolt 76. The cutting bits 75 and the various sockets 74 in the length of the endless cutter chain 73 are disposed at varying angles, so that the cut produced by the successive cutting bits 75 is wider than the cutter bar 70 permitting the latter to be easily withdrawn from the cut. In Fig. 6 the positions of the various cutting bits 75 in the endless chain 73 are shown in broken lines.

Behind the cutter bar 70 there is provided a driven sprocket 77 about which the endless cutting chain 73 is entrained, the endless cutting chain 73 being driven by the sprocket 77. As seen in Fig. 4, the cutter bar 70 is formed with four slots 78 for the reception of the bolts 71. Thus the position of the cutter bar 70 on the support 66 may be adjusted by loosening the bolts 71 and shifting the cutter bar 70 relatively to the support 66. Below the cutter bar there is provided a threaded pin 79 which is threaded into the threaded opening 80 in the support 66. The threaded pin 79 has a collar 81 secured thereto and abutting a shoulder 82 formed on the underside of the cutter bar 70. By loosening the bolts 71 and rotating the pin 79 by means of the collar 81 a force is applied to the shoulder 82 on the underside of the cutter bar 70, and the latter may be shifted in a direction tensioning the endless cutter chain 73. This adjustment may be made for the purpose of taking up wear in the parts of the cutting chain 73, or to adjust the tension in the endless cutting chain 73 according to the material thatis being cut.

The endless cutting chain 73 is driven by the sprocket 77 about which the cutting chain 73 is entrained. The sprocket 77 is mounted at the upper end of a vertical shaft 83, and this shaft projects downwardly below the support 66 where there is secured thereto a worm wheel 84. On the underside of the support 66 there is formed a gear casing 85 within which there is rotatably supported a worm 86 that is engaged with the teeth of the Worm wheel 84 to rotate the shaft 83 and thereby operate the endless cutting chain 73 through the sprocket 77. The worm 86 is driven by a hydraulic motor 87 which is secured to the support 66 below the cutter bar 70. Suitable piping connections are provided for the hydraulic motor 87 from the hydraulic system of the mining machine for the purpose of operating the motor 87 and controls are included for operating the motor as desired.

Since the digging arms 25 on the upper digging head 23 cut an area of the mine face which extends above the top of the mining machine 10 and above the top of the upper cutting head 23 it is apparent that the roof of the mine is formed at a distance above the upper digging head '23 and the mining machine 10. Accordingly, the laterally directed cutting means 55 must be elevated above the top of the upper digging head 23 to form the holes in the side walls of the mine for the reception of timbers to be placed immediately below the roof of the mine to support the same. For this purpose there is provided a hydraulic cylinder and piston mechanism 88 which is interposed between the upper digging head 23 and the slide frame 56. The cylinder and piston mechanism 88 is secured to the upper digging head 23 by a pin 89, and is secured to the slide frame 56 through the medium of an L-shaped arm 90, which is welded to the slide frame 56, and to which the cylinder and piston mechanism 88 is secured by a pin 91. The cylinder and piston mechanism 88 is normally expanded, and to elevate the laterally directed cutting means 55 with respect to the upper digging head-23 the cylinder and piston mechanism is contracted. Conventional hydraulic control means is provided for operating the cylinder and piston mechanism 88, and this is connected to the control station of the mining machine 10. The

guides

57, 58 on the slide frame 56, ride in the vertical tracks 59, 60 respectively, and guide the vertical movement of the laterally directed cutting means. The upward limit of adjustment of the cutting means 55 is determined by the dimensions of the cylinder and pistonmechanism 88. In Fig. 3 there is illustrated the uppermost adjusted position 92 of the upper digging head 23 with respect to the lower digging head 22, and the uppermost adjusted position 93 of the cutting means 55 with respect to the upper digging head 23.

When the cutting means 55 has been positioned vertically, as above described, to place the cutter bar 70 and the endless cutting chain 73 immediately below the roof of the mine, the cutting means 55 may then be fed laterally of the machine 10 into the side wall of the mine to cut a hole therein for the reception of a transverse roof supporting timber. In Fig. 4 there is illustrated the forward end of the mining machine 10 and the two laterally directed cutting means 55 are shown, one in normal retracted position disposed within the perimeter of the machine 10, and the other in projected position wherein it extends beyond the perimeter of the mining machine 10 into the side wall of the mine.

- As previously described, the support 66, which carries the cutter bar 70, is mounted by means of lugs 67 on the horizontal transversely extending guide 63, which is a part of the slide frame 56. it will be apparent that the support 66, with the cutter bar 70, is adapted to move relatively to the guide 63 in a direction transversely of the mining machine 10. Hydraulic cylinder and piston mechanism 95 is utilized to feed the cutting means 55 laterally of the mining machine 10. The hydraulic cylinder and piston mechanism 95 is secured at one end by a pin 96 to the end of the guide 63, and at its other end is secured by a pin 97 to the support 66. As seen in Fig. 5, cylinder and piston mechanism 95 is normally ex tended, and to feed the support 66 laterally of the mining machine 10 the cylinder and piston mechanism 95 is contracted. Suitable hydraulic connections are provided for the cylinder and piston mechanism 95 for the purpose of operating the same, these being controlled by conventional devices from the control station of the mining machine 10. e 1

At the rear of the slide frame 56 there is secured by welding or equivalent means, a pair of fearwardly extending cars 98 between which there is rotatably mounted a roller 99. The roller 99 is adapted to ride on the upwardly facing surface 100 of a stop plate 101 that is secured to the main frame 11 of the mining machine. The surface 100 of the stop plate 101 and the roller 99 cooperate to define the lower limit of movement of the laterally directed cutting means 55. Thus, when the support frame 17 is lowered by means of the hydraulic cylinder and piston mechanism 44 to its lowermost position, as shown by the broken lines in Fig. 3, it will be understood that the digging heads 22, 23 will also be lowered since they are secured to the support frame 17 by the pin 19. However, it is desired that the slide frame 56 and the laterally directed cutting means 55 not drop below the position shown in Fig. 3, in order to prevent these parts from interfering with other parts of the mining .machine 10. In this event the roller 99 rides on the surface 100 of the stop plate 101 and, since the latter is a fixed element, operates to maintain the slide frame 56 and the cutting means 55 in a fixed vertical position.

These is a constant danger in a mine of roof breakdowns and for this purpose it is customary to place timbers acros the roof and to wedge the timbers against the roof for the purpose of supporting it and preventing the hazardous breakdown. The laterally directed cutting means 55, described herein, is operative to cut into the side walls of the mine immediately below the roof for the purpose of forming holes therein within which transversely extending timbers may be placed for the purpose of providing support for the roof. The transversely directed cutting means 55 may be operated in the normal course of the continuous mining operation without interruption of the latter. This is accomplished by a progressive' feed and withdrawal of the laterally directed cuting means 55 into the side walls of the mine as the mining machine 10 advances. Such operation of the laterally directed cutting means 55 does not produce a parallel sided hole in the side walls, but rather produces an opening therein that is triangular in plan sectional view,'t-his being so for the reason that the cutting means 55 is progressively fed into the side wall and progressively withdrawn from the side wall simultaneously with the feed of the mining machine 10 forwardly into the mine face during the normal mining operation. It will be apparent to those skilled in the art that, in the use of the mining machine constructed in accordance with the instant invention the formation of holes in the side walls for the reception of transversely extending roof supporting timbers is accomplished concurrently with the mining operation and thus avoids a separate procedure requiring the use of additional miners. With the holes being formed in the side walls of the mine as described herein, it then becomes a simple matter to place the roof supporting timbers after the mining machine 10 has passed beyond the 'holes in the mine side walls.

Obviously those skilled in the art may make various changes in'the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended, and applicant therefore wishes not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of the invention, what it is desired to secure by Letters Patent of the United States is:

1. In a mobile mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, said digging head including digging means projecting forwardly therefrom, traction means for propelling the mining machine to feed the digging means into the face of a mine, means mounting the digging head on the main frame for vertical adjustment, a laterally directed cutting means disposed behind and adjacent the dlgglng head in an orbit having a portion thereof disposed tangentially to a mine side wall, a slide frame mounting the lat erally directed cutting means behind the digging head, track means on the digging head guiding the slide frame for vertical movement relatively thereto, said slide frame including a laterally extending track for guiding the cutting means, and means to reciprocate the cutting means laterally of the mining machine on the laterally extending track simultaneously with the advance of the mining machine to feed the laterally directed cutting means into a side wall of a mine to progressively cut into the mine side wall as the digging head continuously removes material from the mine face.

2. In a mining machine having a mainframe, a digging head on the main frame at the front end of the machine for digging material from a mine face, means mounting the digging head on the main frame for vertical adjustment, laterally directed cutting means disposed hehind and adjacent the digging head in an orbit having a portion thereof disposed tangentially to a mine side wall, said cutting means comprising a cutter bar and an endless cutting chain carried by the cutter bar, means for driving the cutting chain, a slide frame mounting the laterally directed cutting means behind the digging head, track means on the digging head guiding the slide frame for vertical movement relatively thereto, said slide frame including a laterally extending track for guiding the cutting means, and means to advance the cutting means on the last said track laterally of the mining machine to progressively cut into the mine side wall as the digging head continuously removes material from the mine face. 3. In a mining machine having a main frame, a dig ging head on the main frame at the front end of the machine for digging material from a mine face, means mounting the digging head on the main frame for vertical adjustment, laterally directed cutting means disposed behind and adjacent the digging head, said cutting means comprising a cutter bar and an endless cutting chain carried by the cutter bar in an orbit having a portion thereof disposed tangentially to a mine side wall, a driving sprocket on the cutting means engaged with the cutting chain and means for driving the sprocket, a slide frame mounting the laterally directed cutting means hehind the digging head, the cutter bar being adjustably secured to the slide frame, means to adjust the position of the cutter bar on the slide frame, track means on the digging head guiding the slide frame for vertical movement relatively thereto, said slide frame including a laterally extending track for guiding the cutting means, and means to advance the cutting means on the last said track laterally of the mining machine to progressively cut into the mine side wall as the digging head continuously removes material from the mine face. v 4. In a mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, said digging head including digging means projecting forwardly therefrom, means mounting the digging head on the mining machine for vertical adjustment relatively thereto, said digging means comprising digging arms adapted to dig beyond the top of the mining machine to form a roof in the mine which 'is spaced above the mining machine, laterally directed cutting means carried on the digging head, means for vertically adjusting the laterally directed cutting means relatively to the digging head to a position adjacent the mine roof, means for advancing the laterally directed cutting means laterally of the main frame adjacent the roof to cut into a side wall of the mine at the level of the roof, and stop means disposed between the main frame and the cutting means to fix the lowermost position of the cutting means.

5. In a mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, means mount ing the digging head on the main frame for vertical adjustment, laterally directed cutting means disposed behind and adjacent the digging head, a slide frame mounting the laterally directed cutting means behind the digging head, track means on the digging head guiding the slide frame for vertical movement relatively thereto, means for vertical adjusting the slide frame on the digging head, said slide frame including a laterally extending track for guiding the cutting means, means to advance the cutting means laterally of the mining machine, a stop plate on the main frame, means on the slide frame adapted to engage with the stop plate to fix the lowermost position of the slide frame relatively to the main frame.

6. In a mobile mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, said digging head including digging means projecting forwardly therefrom, traction means on the main frame to continuously advance the mining machine forwardly and feed the digging means into the face of the mine, laterally directed cutting means carried on the digging head for advancing the cutting means forwardly with the forward advance of the mining machine, said cutting means being disposed to operate in an orbit which is substantially tangential to a mine side wall, and means for advancing the laterally directed cutting means laterally of the main frame simultaneously with the forward advance of the cutting means by the mining machine to progressively cut into a side Wall of the mine in forward and lateral directions.

7. In a mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, means for continuously advancing the mining machine in a forward direction to feed the digging head into the mine face, laterally directed cutting means disposed behind and adjacent the digging head, a slide frame mounting the laterally directed cutting means behind the digging head for forward advance of the cutting means with the forward advance of the mining machine, track means on the digging head guiding the slide frame for vertical movement relatively thereto, said slide frame including a laterally extending track for guiding the cutting means, said cutting means being disposed'to operate in an orbit having a portion thereof dispose-d tangentially to a mine side wall, and means to advance the cutting means later-ally of the mining machine on the laterally extending track simultaneously with the forward advance of' the cutting means by the mining machine to progressively cut into the mine side wall in forward and lateral directions as the digging head continuously removes material from the mine face.

8. In a mobile mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, means on the main frame to continuously advance the mining machine forwardly and feed the digging head into the face of the mine, laterally directed cutting means carried on the digging head for advancing the cutting means forwardly with the forward advance of the'mining machine, means for guiding said cutting means in an orbit having a portion thereof disposed tangentially to a mine side wall, means for advancing the laterally directed cutting means laterally of the main frame simultaneously with the forward advance of the cutting means by the mining machine to progressively cut into a side wall of a mine in forward and lateral directions.

9. In a mining machine having a main frame, a digging head on thernain frame at the front end of the machine for digging material from a mine face, means on the main frame to continuously advance the mining machine forwardly to feed the digging head into the mine face, laterally directed cutting means disposed behind the digging head, said cutting means comprising a cutter bar and an endless cutting chain carried by the cutter bar in an orbit having a portion thereof disposed tangentially to a mine side wall, means for driving the cutting chain, a. slide frame mounting the laterally directed cutting means on the mining machine for forward advance of the cutting means with the forward advance of the mining machine, track means on the mining machine guiding the slide frame for vertical movement relatively thereto, said slide frame including a laterally extending track for guiding the cutting means in an orbit having a portion thereof disposed tangentially to a mine side wall, and means to advance the cutting means on the last said track laterally of the mining machine simultaneously with the forward advance of the cutting means by the mining machine to progressively cut into the mine side wall in for-ward and lateral directions as the digging head continuously removes material from the mine face.

10. In a mobile mining machine having a main frame, a digging head on the main frame at the front end of the machine for digging material from a mine face, means on the main frame to continuously advance the mining machine forwardly to feed the digging means into the face of the mine, laterally directed cutting means carried on the min'ing machine for forward advance of the cutting means with the forward advance of the mining machine, means for guiding said cutting means in an orbit having a portion thereof disposed tangentially to a mine side wall, means for advancing the laterally directed cutting means laterally of the main frame simultaneously with the forward advance of the cutting means by the mining machine to progressively cut into a side Wall of a mine in, forward and lateral directions.

References Cited in the file of this patent UNITED STATES PATENTS 1,480,733 Morgan Jan. 15, 1924 2,198,163 Gullick Apr. 23, 1940 2,548,952 Crossland 2.. Apr. 17, 1951 2,694,562 Snyder et al. Nov. 16, 1954 2,699,328 Alspaugh et a1 Jan. 11, 1955 2,770,448 Miller Nov. 13, 1956 FOREIGN PATENTS 595,019 Great Britain Nov. 25, 1947 OTHER REFERENCES Mining Congress Journal, July 1953, page 44.

Mechanical Loading of Coal Underground, by Ivan A. Given, McGra-w-Hill Book Co., Inc., N.Y.C., 194 3, pages 337339.