Control deviation
a control variable and the actual value of a reference variable. When using a regulator controller with a fixed set point, the control deviation describes the difference between the actual value and the
Slave piston principle
principle can also be of electrical design if the pilot element and the main control piston are connected with a double closed loop position control system (Figure F 31) .
Electrohydraulic torque amplifier
Hydraulic drive unit operated electrically using a stepper motor or DC motor with integrated control unit ( following control valve ) and integrated, mostly mechanical feedback . The following control
Thermodynamic measuring
Process to monitor the operating state of a hydraulic system or individual devices with the aid of temperature and pressure measurements . It uses the hydraulic fluid to carry the information and is based
Screw spindle pump
displacement areas between the housing and the spindles, the oil is pushed towards the pressure connection with almost no pulsation. This means that screw spindle pumps are very quiet. However, no volume adjustment
Barrier medium seal
seals ) are not suitable for gases due to their lower viscosity unless they are combined appropriately with a liquid as a barrier medium ( Figure S 73 ). Depending on the design, the pressure in the barrier
O-ring seal
Circular ring with an almost perfectly round cross section which is mainly used in fluids technology to seal machine parts when at rest ( Figure O 11 ). Its sealing action is achieved through axial or
Phase-frequency response
the sinusoidal input signal . In graphical terms, it is mainly represented as a Bode diagram along with the amplitude response based on the value, expressed in logarithmic terms, for the frequency f or
Positive displacement principle
connection). As there is no direct link between the two connections, pumps that operate in accordance with the positive displacement principle ( Displacement machine (displacement unit) ) are well suited to
Printed circuit board
components required or the integrated circuits (IC) are mounted and their wire connections are connected with the conductor tracks by means of dip soldering.