Dust suppression spray valve control for longwall mining

Claim 2

A spray control unit for use in connection with a mining machine travelling along a face, said control unit comprising a housing having inlet and outlet ports; a rotary valve mounted in said housing for angular movement about an axis from a neutral position into second positions disposed one on each side of the neutral position, said valve blocking fluid flow between said inlet and outlet ports when said valve is in its neutral position and permitting such flow when said valve is in either of its second positions; means biasing the valve towards its neutral position; means for delaying the movement of the valve under the action of the biasing means; and an elongate feeler operatively connected with the valve and being swingable about the valve axis, the feeler being adapted to project into the path of the mining machine for deflection thereby in one or other direction depending upon the direction of movement of the mining machine along the face, and to displace the valve during such deflection into one of said second positions.

Claim 3

A unit as claimed in claim 1, wherein said feeler is provided with a spray nozzle, and a duct extends through said feeler from the spray nozzle and is connected with the outlet port.

Claim 4

A unit as claimed in claim 1, wherein the feeler is resiliently deformable.

Claim 5

A unit as claimed in claim 3, wherein the feeler has an outer sleeve consisting of a tightly coiled helical spring.

Claim 6

A unit as claimed in claim 1, wherein the biasing means comprises a spring means and the delay means comprises a brake.

Claim 7

A unit as claimed in claim 5, wherein the spring means is a spiral spring means and means is provided for adjusting the tension in the said spiral spring means.

Claim 8

A unit as claimed in claim 1, wherein the valve is operatively connected to a rotor which is disposed eccentrically with respect to a chamber filled with brake fluid and in which said rotor is housed, the rotor being provided with sliding vanes which divide the cavity remaining in the chamber into two spaces, the housing including a passage interconnecting the two spaces, fluid flow through said passage being constricted.

Claim 9

A unit as claimed in claim 1, wherein the valve is operatively connected to a rotor disposed within a chamber containing a brake fluid, the rotor dividing the brake chamber into two spaces, the housing including a passage which interconnects the two spaces, the passage being constricted by an adjustable throttle member.

Claim 10

A unit as claimed in claim 8, wherein the brake fluid is a fluid such as glycerin, a highly viscous silicon fluid, and the like.

Claim 11

A unit as claimed in claim 8, including a common housing for the valve, the spring and the rotor; the valve, rotor and feeler being directly interconnected.

Claim 12

A unit as claimed in claim 10, wherein the valve and rotor are integral with a shaft on which the feeler is mounted.

Claim 13

A spray control unit for use in connection with a mining machine travelling along a mineral face, said control unit comprising: a. a housing within which is defined a bore forming a valve chamber and a piston chamber, and inlet and outlet ports opening into said valve chamber on opposite sides of a valve seat; b. a valve assembly slidable within said bore, said assembly comprising a valve member for cooperation with said valve seat, a piston chamber, and a follower portion, said valve member being biased towards said seat by pressure of fluid in said piston chamber; c. a shaft mounted for rotaTion in said housing about an axis substantially perpendicular to the axis of the said bore, said shaft being provided with a cam surface for contact with said follower; d. a feeler carried by said shaft, said feeler being adapted to extend in the direction normal of said shaft axis into the path of the mining machine, and means biasing the feeler to that position; and e. said housing having a constricted passage way leading from said piston chamber to a point upstream of said valve seat.

Claim 14

A spray control unit for use in connection with a mining machine travelling along a mineral face, said control unit comprising: a. a housing within which is defined a bore forming a valve chamber and a piston chamber, and inlet and outlet ports opening into said valve chamber on opposite sides of a valve seat; b. a valve assembly slidable within said bore, said assembly comprising a valve member for cooperation with said valve seat, a piston chamber, and a follower portion, said valve member being biased towards said seat by pressure of fluid in said piston chamber; c. a shaft mounted for rotaTion in said housing about an axis substantially perpendicular to the axis of the said bore, said shaft being provided with a cam surface for contact with said follower; d. a feeler carried by said shaft, said feeler being adapted to extend in the direction normal of said shaft axis into the path of the mining machine, and means biasing the feeler to that position; and e. said housing having a constricted passage way leading from said piston chamber to a point upstream of said valve seat.

Claim 15

A unit as claimed in claim 12, wherein the follower has a rounded head and the cam has a recess in which the head is disposed when the valve member is on its seat.

Claim 16

A unit as claimed in claim 13, wherein the recess in the cam is in line with the axis of the valve assembly.

Claim 17

A unit as claimed in claim 13, wherein a clearance exists between the head and cam when the valve member is on its seat.

Claim 18

In a spray control unit for use in mining, said control unit having a housing formed with inlet and outlet ports, and a valve member slidable axially between a first position in which the valve member blocks flow of a fluid between said ports and a second position in which such flow is permitted, the improvement comprising a follower carried by the valve member, a control cam having a recess in which said follower is normally received, a piston slidable in a piston chamber and operative on being displaced by pressure of fluid therein to move said valve member to the said first position, a passage extending through the housing from a position upstream of the valve member to the piston chamber, and adjustable means throttling said passage.

Claim 19

In a spray control unit for use in mining, said control unit having a housing formed with inlet and outlet ports, and a valve member slidable axially between a first position in which the valve member blocks flow of a fluid between said ports and a second position in which such flow is permitted, the improvement comprising a follower carried by the valve member, a control cam having a recess in which said follower is normally received, a piston slidable in a piston chamber and operative on being displaced by pressure of fluid therein to move said valve member to the said first position, a passage extending through the housing from a position upstream of the valve member to the piston chamber, and adjustable means throttling said passage.

Claim 20

In a spray control unit for use in mining, said control unit having a housing formed with a valve chamber and inlet and outlet ports controlled by a valve in the chamber, the improvement comprising a control shaft supported in the housing for angular displacement about an axis, movement of said shaft controlling the position of the valve, a feeler carried on the shaft and adapted to project into the path of the mining machine for deflection thereby about said axis, means biasing the control shaft towards a neutral position, said means comprising a bush closely surrounding the shaft, a sleeve surrounding the bush, a spiral spring interposed between the bush and sleeve and having one end connected to the sleeve and the other end connected to the bush, means for connecting the bush to the shaft for rotation therewith during rotation of the shaft in a first direction, means for connecting the sleeve to the shaft for rotation therewith during rotation of the shaft in a second direction, means for restraining the bush against movement in the second direction and means for restraining movement of the sleeve in the first direction.

Claim 21

In a spray control unit for use in mining, said control unit having a housing formed with a valve chamber and inlet and outlet ports controlled by a valve in the chamber, the improvement comprising a control shaft supported in the housing for angular displacement about an axis, movement of said shaft controlling the position of the valve, a feeler carried on the shaft and adapted to project into the path of the mining machine for deflection thereby about said axis, means biasing the control shaft towards a neutral position, said means comprising a bush closely surrounding the shaft, a sleeve surrounding the bush, a spiral spring interposed between the bush and sleeve and having one end connected to the sleeve and the other end connected to the bush, means for connecting the bush to the shaft for rotation therewith during rotation of the shaft in a first direction, means for connecting the sleeve to the shaft for rotation therewith during rotation of the shaft in a second direction, means for restraining the bush against movement in the second direction and means for restraining movement of the sleeve in the first direction.

Claim 22

A spray control unit for use in connection with a mining machine travelling along a face, said control unit comprising a housing having inlet and outlet ports, a valve movable to connect and disconnect the ports, a feeler for contact with the machine and operatively connected to the valve, a spring biasing the valve to its neutral position in which the valve disconnects the ports, and a brake means for delaying the return of the valve under the action of the spring means.

Claim 23

A spray control unit for use in connection with a mining machine travelling along a face, said control unit comprising a housing having inlet and outlet ports, a valve movable to connect and disconnect the ports, a feeler for contact with the machine and operatively connected to the valve, a spring biasing the valve to its neutral position in which the valve disconnects the ports, and a brake means for delaying the return of the valve under the action of the spring means.

Claim 24

A unit as claimed in claim 18, wherein the braking effect of said brake is adjustable.

Claim 25

A unit as claimed in claim 19, wherein means for adjusting the effect of said brake comprises a throttle member throttling a passage through which fluid is displaced during operation of the brake.

Claim 26

A unit as claimed in claim 18, wherein said brake comprises a brake member movable in a chamber containing a fluid, and a constricted passageway through which fluid is displaced by said brake member, said fluid resisting return of the brake member.

Claim 27

A spray control unit for use in connection with a mining machine travelling along a mineral face, said control unit comprising: a. a housing within which is defined a bore formIng a valve chamber, and inlet and outlet ports opening into said valve chamber on opposite sides of a valve seat; b. a valve assembly slidable within said bore, said assembly comprising a valve member for cooperation with said valve seat, a follower and means biasing said valve assembly to return said valve towards the valve seat, and means delaying the return of the valve member; c. a shaft mounted for rotation in said housing about an axis substantially perpendicular to the axis of said bore, said shaft being provided with a cam surface for contact with the follower; and d. a feeler carried by said shaft, said feeler being adapted to extend in the direction normal of said shaft axis into the path of the mining machine, and means biasing the feeler to that position.

Claim 28

A spray control unit for use in connection with a mining machine travelling along a mineral face, said control unit comprising: a. a housing within which is defined a bore formIng a valve chamber, and inlet and outlet ports opening into said valve chamber on opposite sides of a valve seat; b. a valve assembly slidable within said bore, said assembly comprising a valve member for cooperation with said valve seat, a follower and means biasing said valve assembly to return said valve towards the valve seat, and means delaying the return of the valve member; c. a shaft mounted for rotation in said housing about an axis substantially perpendicular to the axis of said bore, said shaft being provided with a cam surface for contact with the follower; and d. a feeler carried by said shaft, said feeler being adapted to extend in the direction normal of said shaft axis into the path of the mining machine, and means biasing the feeler to that position.

Claim 29

A unit as claimed in claim 22, wherein the means for biasing the valve member towards its valve seat comprises a piston slidable in a piston chamber and a duct for supplying fluid throttling the said duct.