Method and apparatus for controlling the drive of pressure-fluid actuated machine elements

Abstract

Abstract A METHOD AND APPARATUS FOR CONTROLLING THE OPERATION OF MACHINES ELEMENTS DRIVEN BY A FLUID UNDER PRESSURE. A PUMP CONTROLS THE FLOW OF FLUID UNDER PRESSURE AND IS ITSELF ADJUSTED BY A VALVE-CONTROLLED ADJUSTING UNIT. THE LATTER UNIT INCLUDES AN ELECTRICALLY OPERABLE VALVE CONNECTED INTO AN ELECTRICAL CIRCUIT WHICH INCLUDES PRIMARY CONTROL AND AT LEAST ONE SECONDARY CONTROL CONNECTED IN SERIES WITH THE PRIMARY CONTROL AND CONNECTED ELECTRICALLY WITH THIS UNIT FOR CONTROLLING THE LATTER. REFERENCE AND ACTUAL VALUES OF A PRIMARY CONTROL PARAMETER ARE TRANSMITTED BY SUITABLE TRANSMITTER DEVICES TO THE PRIMARY CONTROL WHILE AN ACTUAL VALUE OF A SECOND PARAMETER IS TRANSMITTED TO THE SECONDARY CONTROL TO BE COMBINED THERE WITH THE OUTPUT OF THE PRIMARY CONTROL. IN ADDITION A SIGNAL TRANSMITTER FOR TRANSMITTING A REFERENCE VALUE SIGNAL OF THE SECOND PARAMETER ID PROVIDED, AND THIS LATTER REFERENCE VALUE IS CONNECTED INTO THE CIRCUIT BY A LIMIT SWITCH CONNECTED TO THE OUTPUT OF THE PRIMARY CONTROL SO AS TO BE COMBINED WITH THIS OUTPUT BEFOR IT REACHES THE SECONDARY CONTROL.

Inventors

• 👤 Ludwig Maurer

Bibliographic Details