Control system for a paper or board machine

Claim 2

A control system for regulating a transverse profile of a web in a paper or board machine, having a sensor for detecting the web transverse property profile and producing feedback information, said control system comprising: a plurality of intelligent actuator controllers, each independently executing a predetermined control algorithm and being responsive to an actuator control parameter received as a set value controller signal from a control bus and producing an actuator control signal; a plurality of controllable displacement actuators arranged at profile adjustment points across the width of the web, each being responsive to said actuator control signal from a corresponding one of said plurality of intelligent actuator controllers, each of said plurality of controllable displacement actuators being effective to adjust a transverse property of the web at a corresponding profile adjustment point, said plurality of controllable displacement actuators together being effective to regulate the web transverse property profile, a process controller, having as an output said set value controller signal transmitted as said actuator control parameter for each intelligent actuator controller and receiving as an input the feedback information from the sensor; said data bus being common to said plurality of intelligent actuator controllers and being arranged for data communications between said process controller and said plurality of intelligent actuator controllers, said data bus comprising a serial bus, and said intelligent actuator controllers generating controller information; and a network server connected between said data bus and said process controller for transferring said set value controller signal from said process controller to said plurality of actuator controllers and for communicating said controller information from said intelligent actuator controllers to said process controller.

Claim 3

The control system according to claim 1, wherein each of said plurality of actuator controllers comprises a substantially identical electronic module.

Claim 4

The control system according to claim 1, wherein each of said intelligent actuator controllers comprises an electronic circuit having a processor, memory, serial communication port for communicating with said process controller, actuator control port for controlling said corresponding arc of said actuators, and converter for receiving the output of an actuator movement detector.

Claim 5

The control system according to claim 3, wherein said data bus comprises a serial bus and said memory stores a predetermined program for said processor for control of said serial communication port to control communications with said serial bus.

Claim 6

The control system according to claim 1, wherein said plurality of actuators comprise adjusting spindles of a profile bar of a headbox of a paper machine, each having an angle gear and a stepping motor.

Claim 7

The control system according to claim 1, wherein said plurality of actuators comprise coating blade actuators of a paper-web coating device.

Claim 8

The control system according to claim 1, wherein said plurality of actuators comprise steam box actuators fitted in proximity of the web.

Claim 9

The control system according to claim 1, wherein said plurality of actuators regulate a profile of linear loads in a press nip of a paper machine.

Claim 10

The control system according to claim 1, wherein said plurality of actuators regulate a profile of linear loads in a calendaring nip in an on-line calendar of a paper machine.

Claim 11

The control system according to claim 9, wherein said plurality of actuators comprise inductive profiling devices for controlling said profile of linear loads in said calendaring nip.

Claim 14

The method according to claim 11, wherein said actuators comprise stepping motors, comprising tile further step of: regulating the function of said one of said actuators by said associated one of said actuator controllers by means of feedback received from a linear variable differential transformer displacement detector associated with said one of said actuator, to provide a closed loop servo-regulation of a stepping motor, to control displacement of said one of said actuators.

Claim 15

The method according to claim 11, comprising the further steps of: storing a parameter in one of said actuation controllers relating to a response of an associated one of said actuators to said control signal; and modifying said control signal produced in response to the correction based on said stored parameter.

Claim 16

The method according to claim 11, comprising tile further step of: transmitting a reply from said one of said actuator controllers to said common communication medium after receiving address information to which said one of said actuator controllers is responsive.

Claim 17

A control system for regulating a transverse property profile of a web in a paper or board machine, having a sensor for detecting the web transverse property profile and producing feedback information, said control system comprising: a plurality of intelligent actuator controllers, each executing a predetermined control algorithm and being responsive to an actuator control parameter received as a controller signal from a control bus and producing an actuator control signal; a plurality of controllable displacement actuators arranged at profile adjustment points across the width of the web, each being responsive to said actuator control signal from a corresponding one of said plurality of intelligent actuator controllers, each of said plurality of controllable displacement actuators being effective to adjust a a transverse property of the web at a corresponding profile adjustment point, said plurality of controllable displacement actuators together being effective to regulate the web transverse property profile; and a process controller, having as an output said controller signal transmitted as said actuator control parameter for each intelligent actuator controller and receiving as an input the feedback information from the sensor, said data bus being common to said plurality of intelligent actuator controllers and being arranged for data communications between said process controller and said plurality of intelligent actuator controllers, each of said intelligent actuator controllers comprising an electronic circuit having a processor, memory, serial communication port for communicating with said process controller, actuator control port for controlling said corresponding arc of said actuators, and a converter for receiving the output of an actuator movement detector, each of said intelligent actuator controllers further comprising an input for receiving at least one parameter corresponding to a measurement selected from the group consisting of an operating temperature, a mechanical property and a precision adjustment, an error condition output indicative of a substantial change in at least one parameter outside a normal limit, and an output providing an actuator control signal to said corresponding one of said actuators, produced in accordance with an algorithm for calculating a correction, provided said at least one parameter is within a normal limit, and discontinuing said algorithm if said at least one parameter is not within a normal limit.

Claim 18

A control system for regulating a transverse property profile of a web in a paper or board machine, having a sensor for detecting the web transverse property profile and producing feedback information, said control system comprising: a plurality of intelligent actuator controllers, each executing a predetermined control algorithm and being responsive to an actuator control parameter received as a controller signal from a control bus and producing an actuator control signal; a plurality of controllable displacement actuators arranged at profile adjustment points across the width of the web, each being responsive to said actuator control signal from a corresponding one of said plurality of intelligent actuator controllers, each of said plurality of controllable displacement actuators being effective to adjust a a transverse property of the web at a corresponding profile adjustment point, said plurality of controllable displacement actuators together being effective to regulate the web transverse property profile; and a process controller, having as an output said controller signal transmitted as said actuator control parameter for each intelligent actuator controller and receiving as an input the feedback information from the sensor, said data bus being common to said plurality of intelligent actuator controllers and being arranged for data communications between said process controller and said plurality of intelligent actuator controllers, each of said intelligent actuator controllers comprising an electronic circuit having a processor, memory, serial communication port for communicating with said process controller, actuator control port for controlling said corresponding arc of said actuators, and a converter for receiving the output of an actuator movement detector, each of said intelligent actuator controllers further comprising an input for receiving at least one parameter corresponding to a measurement selected from the group consisting of an operating temperature, a mechanical property and a precision adjustment, an error condition output indicative of a substantial change in at least one parameter outside a normal limit, and an output providing an actuator control signal to said corresponding one of said actuators, produced in accordance with an algorithm for calculating a correction, provided said at least one parameter is within a normal limit, and discontinuing said algorithm if said at least one parameter is not within a normal limit.