Patent ID: 6138564
Filing Date: 2000-10-31
Classification: B65H,G01D,G03G,G05D

Abstract:
A system for regulating pressure in a pressure chamber of a pneumatic brake apparatus for a recording medium within a recording device, comprising:a rotary valve for setting an actual pressure in the pressure chamber dependent on an actual angle of rotation;an angle sensor for acquiring the actual angle of rotation;a pressure sensor for acquiring the actual pressure;a controller for predetermining a target pressure and a corresponding target angle of rotation dependent on at least one of characteristics of the recording medium and operating parameters during recording, the controller determining a pressure deviation between the actual pressure and the target pressure, as well as an angle of rotation deviation between the actual angle of rotation and the target angle of rotation of the rotary valve;an adjustment unit connected for drive from the controller for setting the valve angle of rotation dependent both on the angle of rotation deviation and also on the pressure deviation;said angle of rotation sensor comprising a magnetic unit for producing a magnetic field, a magnetic field sensor for producing an electrical signal and a magnetic reference sensor for producing a reference signal when the magnetic field acts in a predetermined reference angle region so that when the angle of rotation is displaced, a relative rotation occurs between the magnetic field and the magnetic field sensor; andthe adjustment unit setting the angle of rotation at the rotary valve dependent first on the angle of rotation deviation and then dependent on the pressure deviation.