US2795408A

US2795408A - Continuous mining machine with cutter speed control responsive to cutter position

Info

Publication number: US2795408A
Application number: US516356A
Authority: US
Inventors: Goodrich Ross Harry
Original assignee: Joy Manufacturing Co
Current assignee: Joy Manufacturing Co
Priority date: 1955-06-20
Filing date: 1955-06-20
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

June 11, 1957 `R. H. GooDRlcH 2,795,408

CONTINUOUS MINING MACHINE wITH CUTTER SPEED coNTRoI. RESPONSIVE To CUTTER PosI'rIoN W-L-Fw June 11, 1957 R. H. GooDRlcH 2,795,403

CONTINUOUS MINING MACHINE WITH CUTTER SPEED CONTROL RESPONSIVE TO CUTTER POSITION Original Filed Sept. 27, 19494 2 Sheets-Sheet-Z F15. il. I

AI' 1E.

fas@ il 60'0 037262Z.

@MEM- United States Patent CONTINUOUS MINING MACHINE WITH CU'ITER SEIED CONTROL RESPONSIVE TO CU I"I ER PO- S T ON Ross Harry Goodrich, Claremont, N. H., assignor to Joy Manufacturing Company, Pittsburgh, Pa., a corporation of Pennsylvania Continuation of application Serial No. 117,979, September 27, 1949. This application June 20, 1955, Seria No. 516,356

14 Claims. (Cl. 262-28) In mining apparatus of the general type wherein mineral attacking elements are movably supported on a vein attacking instrument and the latter is provided with means for causing it to undergo a sumping movement generally longitudinally thereof followed by movement generally transverse to its directionof longitudinal movement, such movements generally being in a consecutive series of parallel planes, it has been found that if during the sumping movement of the vein-attacking instrument the velocity of the material attacking elements is at a higher rate than the velocity of these elements during its said transverse direction of movement, the resulting effect of the material attaching elements is primarily a cutting operation rather than a tearing operation, with the production of essentially completely tine mineral, while if during the aforementioned transverse movement of the vein-attacking instrument the velocity of the material attacking elements is decreased, an increased tearing action results with the production of less tine mineral.

In Serial No. 47,422 led September 2, 1948 by John R, Sibley and assigned to the assignee of this invention, and now abandoned, there is disclosed a mining machine having a vein-attacking instrument mounted on a slidable support which goes through a cycle of operation cornprising the steps of sumping-in, up-swing retracting, and down-swing and which is well adapted for the present invention. However, it will be appreciated that the present invention is equally as applicable to other types of mining apparatus.

It is an object of the present invention to provide mining apparatus in which the velocity of the material attacking elements is varied as the apparatus undergoes transition from a sumping movement to a shearing movement and then bring the velocity of the mineral attacking elements to sumping velocity at least as sumping is resumed. More particularly it is an object of the invention to provide means for decreasing the velocity of the attacking elements as the apparatus undergoes transition from a sumping action to a shearing action and also provide means for increasing the velocity of the attacking elements to the sumping velocity at least as sumping is again resumed. This and other objects are accomplished by controlling means which are automatically coordinated with the movement of the apparatus through its cycle of operation.

In the drawings:

Fig. 1 is a top plan view of the forward end of a machine of the type described, being substantially Fig. 1 of the above identied application of Sibley, but modified to show this invention.

Fig. 2 is a circuit diagram showing the electric circuit of a preferred embodiment of the invention.

Fig. 3 is a partial view of the circuit shown in Fig. 2 but showing the parts in another operating position.

Figs. 4, 5 and 6 are circuit diagrams similar to Fig. 2 but showing modications in the circuit diagram of the preferred embodiment shown in Fig. 2.

The embodiment of the invention shown in the draw- Patented June 11, 1957 ings consists of a mining machine having a mobile base 2 and a support 4 slidably mounted thereon. Support 4 is not necessarily mounted directly on the mobile base 2 but is preferably mounted on an intermediate base which is mounted for swinging movement about a substantially vertical axis. The details of this portion of the machine are adequately disclosed in the above identied application to Sibley and will not be set forth herein.

A vein-attacking instrument indicated generally at 6 is mounted on support 4 for swinging movement about a substantially horizontal axis, as is clearly disclosed in the Sibley application identied above. Disintegrating elements 8 are mounted in blocks 10 of continuous chains which move in prescribed paths on the framework of the vein-attacking instrument. Thus the disintegrating elements 8 move in orbital paths about the vein-attacking instrument, as will be understood by those skilled in the art.

Two electric motors 12 are mounted on the intermediate base and are connected by a telescoping shaft drive mechanism through a suitable gearing to drive the chains, including the blocks 10, thus effecting drive -of the disintegrating elements 8 in said orbital paths.

As is best seen in Fig. 2, the electric motors 12 are preferably compound-wound direct current motors. Fig. 2 shows a circuit diagram of one such motor in which the armature 14 and the series field 16 are connected in series across the power line, and a shunt field, consisting of a resistance 18 and a coil 2i), is connected across the line in parallel with the armature.

As is clearly disclosed in the above identified Sibley application, the motors 12 swing from side to side with the vein-attacking instrument 6, but do not advance and retract with said instrument. As is best seen in Fig. 1, a normally-open push-button switch 22 is mounted on a bracket 24 beside the lefthand motor 12. A second pushbutton switch 26, which is normally closed, may be mounted on the rst switch 22. A switch actuator 28 is mounted on the slidable support 4 for movement forward and backward therewith. Switch actuator mechanism 28 includes an elongated cam portion 30 having a short inclined surface 32 positioned to engage the button of switch 22 to close the normally open contacts thereof, and a projection 34 substantially at right angles to the elongated cam 3i) to engage the button of normally closed switch 26. The elongated cam 30 has a surface 36 which intersects with the inclined surface 32 and is substantially parallel to the axis of forward and rearward movement of the slidable support 4 and serves to hold the switch 22 closed after it is closed by the inclined surface 32.

According to the present invention means are provided for automatically varying the rate of orbital movement for the mineral attacking elements upon the transition from a sumping action to a shearing action and means are also provided for bringing the velocity of the attacking elements back to their surnping rate at least as sumping is again resumed. In a preferred ernbodiment of the invention this is accomplished by varying the field strength of the motor and preferably by varying the strength of the shunt field by, in the form of the invention shown, shunting out the resistance 18. To that end, there is provided a shunt circuit 38 which comprises a conductor 4t) tapped into the field between resistance 18 and coil 20 at 42, a conductor 44 connected to the other end of resistance 18, a stationary contact 46 connected to conductor 44, a stationary contact 4S connected to conductor 40 and a bridging contact 50 positioned to complete a circuit between the

contacts

46 and 48.

Bridging contact 50 is the moving contact of a normally-closed relay 52 having an energizing coil 54. One end of coil 54 is connected to one side of the line by a conductor 56, and the other end of coil 54 is connected to a stationary contact 58 of switch 22 by a conductor 60. Another stationary contact 62 or" switch 22 is positioned adjacent contact 58 in position to be connected therewith by bridging contact 64 actuated by the pushbutton of the normally-open switch 22. A conductor 66 connects the contact 62 with stationary contact 68 of switch 26. A stationary Contact 70 of switch 26 is positioned adjacent contact 68 to be connected therewith by a bridging contact 72 which is actuated by the pushbutton of the normally-closed switch 26. A conductor 74 connects the contact 70 with the other side of the line.

Although Fig. l shows two

motors

12, 12, only one such motor is shown in Fig. 2. It will be understood by those skilled in the art that a second motor can be controlled by relay 52 simply by providing the relay with another set of contacts similar to contacts 46, 43, and 5t), the second set of

contacts

46, 48 being in the shunt circuit for that portion of the eld circuit of the second motor which is to be shunted out.

Operation As the vein-attacking instrument is advanced in the sumping-in step of a cycle of operation, the inclined surface 32 of the switch actuator 28 closes the normally open switch 22, energizing the coil 54.0f relay 52 through conductor 56, coil 54, conductor 60, stationary contact 58, bridging contact 64, stationary contact 62, conductor 66, stationary contact 68, bridging contact 72, stationary contact 70, and conductor 74. With the relay 52 thus energized, the normally closed contacts of the relay are opened by the bridging contact 50, and the resistance 18 is placed in series with coil 20, reducing the voltage across the coil and thus reducing the field strength. With the motor ield reduced, the motor 12 runs at a substantially higher speed.

This increased speed of motor 12 is maintained throughout the sumping-in step until the vein-attacking instrument nears the end of its forward movement, at which time the projection 34 engages the button of normally-closed push-button switch 26 and moves the bridging contact 72 out of engagement with stationary contacts 68 and 70, as is best seen in Fig. 3. This movement breaks the energizing circuit of the relay 52, allowing the contactor to drop in and thus closing the circuit 38 and thus again shorting out resistance 18 of the shunt iield circuit and putting full voltage on coil 20. With the increased tield thus provided, the motor again runs at a decreased speed and maintains that decreased speed as long as switch 26 is held open by the projection 34. This condition will normally obtain throughout the up-swing of the vein-attacking instrument:

When the up-swing step of the cycle of operation is completed, the vein-attacking instrument 6 is retracted to clean up the roof. As the retraction portion of the step is begun, the contacts of switch 26 are closed, thus again energizing the relay 52 to put the resistance 18 of the shunt iield circuit back in the circuit. The motor then again runs at an increased speed and continues to do so until the vein-attacking instrument has reached a point near its fully retracted position, at which time the switch 22 opens again and the relay 52 is once more (le-energized. With the vein-attacking instrument in the fully retracted position, the instrument is moved down through the down-swing step of the cycle of operation and the vein-attacking instrument is ready to he swung about its vertical axis, for the width of said instrument, putting it in position for another cycle of sumping-in, tip-swing, retracting and down-swing.

lt will, of course, be understood by those skilled in the art that the push-button switches 22 and 26 and the relay 52 are shown schematically only and that appropriate switches for the intended use will be provided.

This will, of course, include the use of suitable explosion-proof switches where such are required.

It will be evident to those skilled in the art that there is here provided a continuous mining machine with fully automatic controls for providing high-speed operation of the disintegrating elements during the sumpingin and retracting steps of the cycle of operation and lowspeed drive of the disintegrating elements for the upswing and down-swing step of the cycle of operation.

It will further be evident to those skilled in the art that modiiications of the invention may be effected without departing from the spirit of the invention. For example, the drive motors 12', 12 for the disintegrating elements could each be provided with two shunt fields, and the circuit of `one of these could be opened to provide the desired reduction in eld strength; see Figs. 4 and 6. As an example of still another modification, the actuator 28 could be provided at its back end with another inclined surface 32' similar to the incline 32, in which case switch 26 could be eliminated because switch 22 would serve to close the circuit of relay 52 at the beginning of sumping-in and to open it at the end of that step; see Figs. 5 and 6. Other modifications to accomplish the invention will be evident to those skilled in the art.

The present application is a continuation of my copending application Serial No. 117,979 led September 27, 1949, now abandoned.

What I claim is:

1. In a mining apparatus having a vein-attacking instrument supported for movement selectively generally longitudinally thereof and generally transversely to its direction of longitudinal movement and having means for causing it to undergo such movements, mineral attacking elements movably supported on said instrument, means including a motor for driving said attacking elements during both of said movements and at a materially higher speed during one of the same than during the other thereof, and means, including controlling means for said driving means automatically coordinated with at least one of said movements of said vein-attacking instrument for causing said elements to be driven during at least the major portion of said movement transversely to said direction of longitudinal movement, at a slower speed than during said movement generally longitudinal thereof.

2. In a mining apparatus having a vein-attacking instrument supported for a sumping movement followed by a shearing movement and having means for causing said instrument to undergo such sumping and shearing movements, mineral attacking elements movably supported on said instrument, motor operated means for driving said attacking elements during each of said movements and at different speeds respectively during sumping movement and during shearing movement, and controlling means for automatically conforming the rate of drive of said elements to the movements of the instrument, including controlling means automatically coordinated with at least one of said movements of said instrument causing the elements to be driven during at least the major portion of said shearing movement more slowly than during the major portion kof said sumping movement.

3. In a mining apparatus having a vein-attacking instrument supported for a sumping movement followed by a shearing movement and having means for causing said instrument to undergo such sumping and shearing movements, mineral attacking elements movably supported on said instrument, motor means for driving said attacking elements during each of said movements and at different speeds respectively during sumping and shearing and having controlling means for effecting drive selectively at said different speeds, means controlled by movement of said instrument for positioning said controlling means at least substantially throughout sumping to cause said motor means to drive said elements at said higher speed, and to reposition said controlling means for causing said motor means to drive said elements at said lower speed during shearing,

4. In a mining apparatus having a Vein-attacking instrument supported for a sumping movement followed by a shearing movement and having means for causing said instrument to undergo such sumping and shearing movements, mineral attacking elements supported on said instlument for travel in an orbital path, motor means for driving said attacking elements during each of said movements and at different speeds respectively during sumping and shearing and having controlling means for effecting drive selectively at said different speeds, means responsive to the initiation of sumping to actuate said controlling means to effect drive of said elements by said motor means at a higher speed and means responsive to the completion of sumping to reduce the speed of drive of said elements by said motor means.

5. In a mining apparatus having a vein-attacking instrument mounted for movement through a cycle including at least sumping-in and up-swing and having means for causing said instrument to undergo such sumping-in and up-swing, in combination: material attacking elements supported on said instrument for travel in an orbital path, means to drive the attacking elements at a given speed during sumping-in and at a lower speed during up-swing, means responsive Vto the starting of sumping-in to bring said drive means to said given speed as the sumping-in step is begun, and means responsive to the completion of sumping-in to bring the drive means to said lower speed at least approximately as the attacking instrument reaches the end of its sumping-in stroke and initiates up-swing.

6. In a mining apparatus having a vein-attacking instrument mounted for movement through a cycle involving the steps of sumping-in, up-swing, retracting, and down-swing, and vein disintegrating elements mounted on the instrument for movement in orbital paths, and having means for moving said instrument through said cycles, in combination: means to drive said elements in said paths at a given speed during the down-swing and up-swing of said attacking instrument, means responsive to the starting of sumping-in and responsive to the starting of retracting movement to drive said elements at a greater speed during said sumping-in and retracting, said last means being responsive to the completion of the sumping-in and responsive to the completion of retracting movement to restore the drive means to said given speed.

7. In a mining apparatus having a vein-attacking instrument, means to move the instrument through a cycle of steps comprising at least sumping and shearing, and material attacking elements movably mounted on said instrument, in combination: an electric motor having a eld and connected to drive the attacking elements, means to vary the strength of the motor field, the last-named means including a relay, means to energize the relay, and operating means responsive to changes in position of said instrument for the relay energizing means to drive said motor at a given speed during the shearing movement of said instrument and at a higher speed during the sumping movement of said instrument.

8. A mining machine according to claim 7, in which the means to vary the iield strength consists of a shunt for a portion of the field circuit, and the recited relay connected to open or close the shunt circuit.

9. A mining machine according to claim 8, in which the means to energize the relay includes electric switch means; the recited operating means being mounted for movement responsive to sumping movement of the veinattacking instrument.

10, A mining machine according to claim 7, in which the means to energize the relay includes electric switch means; the recited operating means being mounted for movement responsive to sumping movement of the veinattacking instrument.

11. In a mining machine having a mobile base and a support slidable thereon, a vein-attacking instrument mounted on the slidable support and including material attacking elements, and `means including the support to move the instrument through a cycle of steps comprising at least sumping and shearing, in combination: an electric motor having a iield circuit and connected to drive the attacking elements, a shunt circuit for a portion of the eld circuit, a relay having contacts in the shunt circuit, a circuit connected to energize the relay, switch means in the last-named circuit, and switch operator means mounted for movement with the slidable support to effect the closing of the relay energizing circuit for at least substantially the entire sumping movement of said instrument and to effect an opening of that circuit for at least ysubstantially the entire shearing movement of said instrument.

12. A mining machine according to claim 11, in which the switch means consists of a normally open switch and a normally closed switch in series, the switch operator means including a cam positioned to close the normally open switch when the sumping step begins and a projection positioned to open the normally closed switch as the sumping step approaches completion.

13. A mining machine according to claim 11, in which the motor eid circuit comprises a coil and a resistance in series, the resistance being connected to be shunted out by the recited shunt circuit.

14. In a mining machine having a mobile base and a support slidable thereon, a vein-attacking instrument mounted on the slidable support and including material attacking elements, and means including the support to move the instrument through a cycle of steps comprising snmping-in, upswing, retracting, and down-swing, in combination: an electric motor having a shunt eld circuit comprising a resistance and a coil in series and connected to drive the material attacking elements, a 'shunt circuit for the resistance, a relay having contacts in the shunt circuit, a circuit connected to energize the relay, switch means in the last-named circuit, and switch operator means mounted for movement with the slidable support to eiect a closing of the relay energizing circuit for at least substantially the entire sumping-in and retracting movements of said instrument and to eect an opening of that circuit for at least substantially the entire up-swing and down-swing of said instrument.

References Cited in the file of this patent UNITED STATES PATENTS 1,008,593 Fish Nov. 14, 1911 1,588,564 Wilson .lune 15, 1926 1,950,544 Driehaus Mar. 13, 1934 2,269,781 Osgood Jan. 13, 1942 2,415,217 Osgood Feb. 4, 1947 2,424,138 Barr July 15, 1947 2,469,594 Danforth May 10, 1949