초록

A pulse width modulated pressure source wherein the path between a fixed pressure source and an output receiving port is interrupted periodically so that the receiving port receives a modulated pressure of a controlled value less than the predetermined pressure source.

대표청구항 ▼

A pressure source of a desired magnitude dependent upon the respective durations of pulse width modulated binary input signals comprising: pressure source means of predetermined magnitude having an output member to transmit pressure; receiving means having an input member to receive pressure; interr

A pressure source of a desired magnitude dependent upon the respective durations of pulse width modulated binary input signals comprising: pressure source means of predetermined magnitude having an output member to transmit pressure; receiving means having an input member to receive pressure; interruptable path means having an input to receive the binary input signals and operable upon receipt of signals of a first characteristic to fully open a flow path between the output member and the input member for a first pulse width modulated control period and upon receipt of signals of a second characteristic to completely close the flow path between the output member and the input member for a second pulse width modulated control period, the duration of the first pulse width modulated control period compared to the duration of the second pulse width modulated control period causing the pressure at the receiving means to be of the desired magnitude wherein said interruptable path means includes a valve having a rotatable shaft with first and second ports formed therein and a housing member around said rotatable shaft with first and second ports formed therein the second port of the housing means lying adjacent of the second port of the shaft during all positions of rotation of the shaft; means rotating the shaft between first and second positions, in the first position the first port of the housing means being aligned with the first port of the shaft and in the second position the first port of the housing means being non-aligned with the first port of the shaft.