Control system for a multilayer headbox using an ultrasonic transducer
US4526653A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1982 |
| Grant date | Jul 2, 1985 |
| Priority date | — |
| Expiry date | Sep 28, 2002 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21G9/0027
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A control system for controlling a multilayer headbox for a paper machine, which headbox there are three channels converging in the direction of flow and through which stock is conducted from separate inlets to discharge slots at the slice opening for discharge of layer-forming stock jets. Each channel is connected by a feed pipeline for stock supply by means of a motor-driven pump, the speeds of which are controlled by individual speed regulator units. The control system includes a first controller, which emits an output signal as a function of a possible deviation of an actual value of the pressure of the stocks inside the headbox from a setpoint for the pressure, which output signal is transmitted to all speed regulator units in order to regulate the speeds of the motors synchronously and, by means of the pumps, to alter synchronously the stock supply to the channels. The control system additionally comprises ultrasonic transducer means arranged in proximity to the slice opening in order to obtain information about the distance between two channel-forming surfaces in respective channels, which distance information is transmitted to an electronic measuring unit connected to the t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.