Feeder crusher

Abstract

A mobile, low-profile feeder-crusher machine for receiving, crushing and feeding freshly mined coal to a stationary conveyor system includes a rigid frame supporting a rotary crusher shaft and supporting an endless conveyor for delivering coal to the crusher shaft and for removing crushed coal therefrom. The drive system for the crusher shaft is mounted on the frame and includes a hydraulic pump driven by an electric motor, a hydraulic motor driven by the pump, a planetary gear reduction driven by the hydraulic motor and having a carrier output driving the crusher shaft, and a flywheel rotatable with the input of the reduction gear assembly.

Description

as its major parts a receiving section 12, a crusher section 14 and a discharge section 16. The receiving section 12 is a hopper-like structure open at both ends and at the top and being formed of by side walls 18 and 20 and a bottom wall 22, the latter extending the length of the machine and thereby forming the bottom wall of the crusher section 14 and of the discharge section 16. The discharge section 16 includes side walls 24 and 26 and lateral support shelves 28 and 30 for supporting the components of the power system, such as an electric motor 32, hydraulic pumps 34 and a reservoir 36 for the hydraulic system. In the interest of simplicity the connections between the pumps 34, the various hydraulic motors and the reservoir 36 are not shown.

The three sections 12, 14 and 16 together with various frame members form a unitary rigid body which is supported from the ground by two transversely-spaced endless-thread crawler units 38. The connection between each crawler unit 38 and the body is a tube and shaft-like assembly 40 having a tubular end 42 which is fixed to the frame of the unit 38 and a shaft end 44 which is bolt-connected to the body at 46 for limited rotation about a transverse horizontal axis. A hydraulic piston and cylinder unit (not shown) connected between the body and the frame of the crawler unit determines the angular position of the body relative to the crawler units 38. The drive system for each crawler unit 38 includes a hydraulic motor 48 which receives pressure fluid from one of the pumps 34.

The crusher section 14 includes a rigid horizontal shaft 50 mounted transversely in the machine and provided with a plurality of radial breaker arms 42 or hammers. The circle 54 defined by the outer ends of the arms 52 during rotation of the shaft 50 lies slightly above the bottom wall 22 of the machine so that coal and rock will be crushed in passing through the space between the circle 54 and the wall 22. During operation of the machine coal and rock are urged into this space by a series of longitudinally spaced apart transverse flights 56 which are moved from left to right along the upper surface of the bottom wall 22 by means of a pair of spaced-apart endless chains the upper run of which is illustrated at 58. The chains 58 are looped over sprockets 60 and are driven by hydraulic motors 61 powered from one of the pumps 34. The crushed material is then carried by the flights 56 from the crusher section 14 to the right hand end of the machine.

All of the above is generally conventional in feeder-crusher machines. According to the present invention the The drive system for the crusher shaft 50 includes a planetary gear reduction unit 62 having a low speed output driving the crusher shaft 50 and having a high speed input carrying a flywheel 68. The input shaft 66 also carries a secondary input gear 70 which meshes with a primary input gear 72 carried by the shaft 73 of a hydraulic motor 74 driven by one of the pumps 34.

As seen in FIG. 3 the planetary gear unit 62 includes a sun gear 76 carried on the input shaft 66 and four planet gears 78 meshing with the sun gear 76 and with an internally toothed ring gear 80. An end 64 of the crusher shaft 50 is carried by a planet gear carrier 82. The ring gear 80 is fixed against rotation, preferably by being made unitary with the body and/or frame of the machine.

In use the machine is propelled into a low clearance mine area by means of the crawler units 38, under the control of an operator. Electric current for the motor 32 is supplied to the machine by a cable (not shown). The control valves for the various hydraulic motors are carried by the machine but are not shown inasmuch as they may be are conventional features of a feeder-crusher. When the machine has been properly located, the sprocket motors 61 and the crusher motor 74 are set in motion and coal is loaded into the receiving section 14. The moving flights 56 urge the uncrushed coal into the hammer circle 54 of the crusher and then urge the coal crushed by the breaker arms 52 into the discharge section 16.

The system of flights 56 and chains 58 can be designed and constructed to transport the uncrushed and crushed coal at essentially any practical rate and the ability of the crusher is therefore the limiting feature of the machine's throughput. As described earlier this limiting feature is overcome to a large extent by providing by connecting a flywheel 68 at to the high-speed input shaft of the speed reducer so that the torque applied available to the crusher shaft 50 is amplified by the rapidly rotating significantly increased for a given flywheel 68. The amplification increase is, of course, proportional to a function of the weight of and the square of the speed of rotation of the flywheel 68, and for a given crusher the weight of the flywheel to be used will be selected on the basis of the desired increase in torque, subject to the space available for the flywheel, the speed of rotation of the input and the ability of the crusher to withstand higher stresses. Preferably the flywheel should produce a minimum increase of 25% in the torque applied to available at the crusher shaft , over that which is available without the flywheel. The speed reducer is preferably of the planetary gear type because this type of construction is capable of absorbing the high stresses which will develop when the amplified torque applied to the crusher shaft 50 overcomes a resistance which would cause jamming of the crusher if the amplified torque was not present.

It will be understood that the term flywheel means a discrete body of revolution of greater diameter and mass than the shaft on which it is carried. The flywheel may have its mass concentrated, ring-like, near its periphery as shown, or it may be a disc of uniform thickness.

Claims

1. A feeder-crusher machine for use in low clearance mines comprising an elongated low-profile body supported from the ground on traction means so as to be movable along the ground longitudinally, said body having side walls and a bottom and including, in end-to-end relationship along the length of the machine, a receiving section, a crushing section and a discharge section; said crushing section including a rotary crusher shaft mounted transversely in said body and carrying a plurality of radial breaker arms the outer ends of which define a circle spaced from a wall of the machine; means for urging material residing on said bottom in said receiving section to the space between said circle and said wall so as to be crushed therein and for urging the resulting crushed material along the discharged section in a direction away from said crusher section; and drive means mounted on said body for rotating said crusher shaft, said drive means including a constant-speedmotor, a mechanical speed reduction unit having a high speed input driven by said motor, a low speed output driving said crusher shaft, a gear system connected between the input and the output for rotating the output at a speed proportional only to the speed of the input and a flywheel connected to rotate with said high speed input to said speed reduction unit whereby amplified torque produced by the high speed flywheel is transmitted through the gear connections in said reduction unit to the more slowly rotating crusher shaft.

2. A feeder-crusher as in claim 1 wherein said speed reduction unit includes a planetary gear set having a sun gear, another gear, planet gears meshing with said sun gear and said other gear and a planet carrier, said other gear being fixed to said body, said sun gear being driven by said motor and said carrier driving said low speed output. 3. In an impact-type crushing machine: a rotary crusher shaft carrying impact means; fixed means against which material is crushed by the action of the impact means on the material; a high speed motor; a planetary gear reduction unit having a sun gear, another gear, planet gears meshing with said sun gear and with said other gear and a planet carrier; means fixing said other gear against rotation; a first driving connection between said motor and said sun gear, said first driving connection including a flywheel which amplifies the torque supplied through said meshing gears to said crusher shaft. 4. A crusher maching having a crusher section; a movable breaker surface within the crusher section; a means for moving material to the crusher section; a rotating power source; and a means for driving the breaker surface from the rotating power source comprising: a rigid speed reduction system having a relatively high rotating speed input connected to be driven by the power source and a relatively low speed output connected to move the breaker surface, and a flywheel attached to rotate with the input whereby the inertial energy of rotation of said flywheel is transmitted through the reduction system to the breaker surface. 5. A crusher machine according to claim 4 wherein said machine is a feeder crusher machine. 6. A crusher machine according to claim 4 wherein said movable breaker surface is a rotating crusher shaft with breaker arms mounted on said shaft. 7. A crusher machine according to claim 4 wherein said speed reduction system comprises a planetary gear unit. 8. A crusher machine according to claim 7 wherein said machine has a frame and wherein said planetary gear unit has a ring fixedly attached to same frame. 9. A crusher machine having a crusher section; a movable breaker surface within the crusher section; a means for moving material to the crusher section; and a means for driving the breaker surface from a rotating power source comprising: a rigid speed reduction system having a relatively high rotating speed input adapted to be driven by a rotating power source, a relatively low speed output connected to drive the breaker surface, and a flywheel attached to rotate with the input whereby the inertial energy of rotation of said flywheel is transmitted through the reduction unit to the breaker surface. 10. A crusher machine according to claim 9 wherein said movable breaker surface is a rotating crusher shaft with breaker arms mounted on said shaft. 11. A crusher machine according to claim 9 wherein said speed reduction means comprises a planetary gear unit. 12. A crusher machine according to claim 11 wherein said machine has a frame supporting its parts and wherein said planetary gear unit has a ring gear fixedly attached to said frame. 13. A crusher machine having a crusher means for crushing material adapted to be driven by a rotating input; a means for moving material to the crusher means; a means for rigidly driving the crusher means at a relatively low rotating speed from a relatively high speed of rotating input: and a flywheel attached to rotate with the input. 14. A crusher machine according to claim 13 wherein said machine is a feeder crusher machine. 15. A crusher machine according to claim 13 wherein said crusher means comprises a rotating crusher shaft with breaker arms mounted on said shaft. 16. A crusher machine according to claim 13 wherein said means for driving comprises a planetary gear unit. 17. A crusher machine according to claim 16 wherein said machine has a main support frame and wherein said planetary gear unit has a ring gear fixedly attached to said frame. 18. A crusher machine having a crusher shaft, a power means for producing a rotating output, a speed reduction means connected to receive the rotating output for rigidly transmitting said rotating output to the crusher shaft at a reduced speed of rotation, and a flywheel having a selected mass connected to rotate with the rotating output to thereby provide energy.