Disc type refiner with automatic plate spacing control

Claim 2

A disc type refiner for the refining of paper pulp and the like comprising a base, a rotor mounted for rotation on said base, a motor for driving said rotor in rotation, a refining surface on said rotor, a non-rotating head on said base, a refining surface on said non-rotating head in juxtaposed relation to said rotor refining surface, means for axially adjusting the position of said non-rotating head to control the spacing of said juxtaposed refining surfaces, feed means for introducing materials to be refined between said refining surfaces, means for monitoring the flow rate of material through said feed means, and means for continuously adjusting the spacing of said refining surfaces in acCordance with the flow rate of material through said feed means to provide a constant work input to the material despite fluctuations in the material flow rate.

Claim 3

The invention as claimed in claim 1 wherein said feed means includes a drive motor and wherein said means for monitoring the flow rate through said feed means comprises means for monitoring the power consumed by said feed means drive motor.

Claim 4

The invention as claimed in claim 1 wherein said feed means comprises a screw conveyor, and an electric motor for driving said screw conveyor, said means for monitoring the flow rate of material through said feed means comprising means for monitoring the power consumed by said electric motor.

Claim 5

The invention as claimed in claim 3 wherein said means for axially adjusting the position of said non-rotating head comprises a hydraulic cylinder, a pressurized fluid source connected with said hydraulic cylinder, and electrically controlled valve means for controlling the flow of fluid from said source to said hydraulic cylinder.

Claim 6

A disc type refiner for the refining of paper pulp and the like comprising a base, a casing on said base, a rotor passing through said casing and mounted for rotation therewithin, said rotor being axially fixed with respect to said casing, a motor operatively connected to said rotor for driving said rotor in rotation, said rotor comprising a rotor disc extending radially therefrom, refining plates mounted on each axial face of said rotor disc, a non-rotating head mounted within said casing adjacent each axial face of said rotor disc, refining plates on each of said non-rotating heads juxtaposed said rotor refining plates, means for axially adjusting the position of each of said non-rotating heads to control the spacing of said juxtaposed refining plates, feed means for introducing materials to be refined between said refining plates, means for monitoring the flow rate of material passing through said feed means, and means for continuously adjusting the spacing of said refining plates in accordance with the flow rate of material through said feed means to provide a constant work input to the material despite fluctuations in the material flow rate.

Claim 7

A disc type refiner for the refining of paper pulp and the like comprising a base, a casing on said base, a rotor passing through said casing and mounted for rotation therewithin, said rotor being axially fixed with respect to said casing, a motor operatively connected to said rotor for driving said rotor in rotation, said rotor comprising a rotor disc extending radially therefrom, refining plates mounted on each axial face of said rotor disc, a non-rotating head mounted within said casing adjacent each axial face of said rotor disc, refining plates on each of said non-rotating heads juxtaposed said rotor refining plates, means for axially adjusting the position of each of said non-rotating heads to control the spacing of said juxtaposed refining plates, feed means for introducing materials to be refined between said refining plates, means for monitoring the flow rate of material passing through said feed means, and means for continuously adjusting the spacing of said refining plates in accordance with the flow rate of material through said feed means to provide a constant work input to the material despite fluctuations in the material flow rate.

Claim 8

A disc type refiner as claimed in claim 5 wherein said feed means for introducing materials between said refining plates comprises a screw conveyor adjacent each said nonrotating head, and an electric drive motor for each said screw conveyor, said means for monitoring the flow rate through said feed means comprising means for monitoring the power input to each said conveyor drive motor.

Claim 9

The invention as claimed in claim 6 wherein said means for axially adjusting the position of each of said nonrotating head comprises a hydraulic cylinder, a pressurized fluid source connected with said hydraulic cylinder, and electrically controlled valve means for controlling the flow of fluid from said source to said hydraulic cylinder.

Claim 10

The invention as claimed in claim 7 wherein said rotor includes a ribbon conveyor extending axially therealong at each side of said rotor disc for feeding material from said screw conveyors toward said disc and into the space between said refiner plates.

Claim 11

The invention as claimed in claim 7 wherein said rotor motor comprises an electric motor, means for monitoring the power input to said rotor motor, pressure sensing means associated with said hydraulic cylinders for sensing the cylinder pressure and hence the force generated by said cylinders, said means for continuously adjusting the spacing of said refiner plates comprising an electric control circuit connected with said pressure sensing means, said valve means, and with said means for monitoring the input power to said refiner motor and screw conveyor motors.

Claim 12

Control means for a refiner having opposed relatively rotatable refining plates, hydraulic means for adjusting the spacing of said plates, refiner motor means for driving said plates, feed means for feeding process material through said plates For refinement, and feed motor means for the feed means, comprising means for sensing power of the feed motor means and means for producing a signal T proportional thereto representative of tons of feed, means for sensing power of the refiner motor means and means for producing a signal HP proportional thereto representative of drive horsepower, and means sensing pressure P in the hydraulic means controllng spacing of the opposed plates and producing a signal P proportional thereto, means to combine said signals in accordance with the formula (HP.K1) (P.K2)/(T.K3), where K1, K2 and K3 are constants dependent upon individual refiner performance, and produce an output signal representative thereof, a setpoint controller for comparison of said output signal with a predetermined signal level, and adjust means for adjustment of the hydraulic means responsive to the setpoint controller to make correction of spacing of the plates of the refiner by the hydraulic means upon deviation from the setpoint by a predetermined amount.

Claim 13

Control means for a refiner having opposed relatively rotatable refining plates, hydraulic means for adjusting the spacing of said plates, refiner motor means for driving said plates, feed means for feeding process material through said plates For refinement, and feed motor means for the feed means, comprising means for sensing power of the feed motor means and means for producing a signal T proportional thereto representative of tons of feed, means for sensing power of the refiner motor means and means for producing a signal HP proportional thereto representative of drive horsepower, and means sensing pressure P in the hydraulic means controllng spacing of the opposed plates and producing a signal P proportional thereto, means to combine said signals in accordance with the formula (HP.K1) (P.K2)/(T.K3), where K1, K2 and K3 are constants dependent upon individual refiner performance, and produce an output signal representative thereof, a setpoint controller for comparison of said output signal with a predetermined signal level, and adjust means for adjustment of the hydraulic means responsive to the setpoint controller to make correction of spacing of the plates of the refiner by the hydraulic means upon deviation from the setpoint by a predetermined amount.

Claim 14

The control system of claim 10 in which the control of the hydraulic means includes a servo valve regulating flow to the hydraulic means and a servo amplifier controlling the valve in response to the control signal.

Claim 15

The control system of claim 11 wherein said hydraulic means comprises a hydraulic cylinder, means sensing the pressure on the opposite sides of said cylinder, a differential amplifier for receiving and comparing the signals from said latter pressure sensing means to generate a signal proportional to any difference in pressures, said servo valve and said differential amplifier providing feedback to said servo amplifier.

Claim 16

The control system of claim 10 in which said refiner comprises two pairs of opposed plates each adjustable relative to one another, and a pair of feed means, one for each pair of plates, and each having its own drive means, wherein the signals from the respective feed motors are summed, the outputs of the respective hydraulic cylinders are compared and the higher pressure used as the pressure signal.

Claim 17

The control system of claim 13 in which signals from feed motors are subtracted by differential amplifier means and are compared with a standard and an alarm is activated when the differential exceeds a predetermined amount.

Claim 18

The control system of claim 13 in which the pressure signals are applied to a differential amplifier and a difference signal derived such that, when the difference signal exceeds a predetermined amount, alarm means is activated.