Position/time diagram
Of a cylinder : Qualitative illustration of the movement process of a cylinder , starting with the acceleration phase and the different working movements over the holding phase to the reflux ( Figure W
Concentrates
Elements to be mixed in with pressurised water ( HWBF ) to give the water lubricity and corrosion protection. They usually make up 2 to 5% of a hydraulic fluid. A distinction is made between three groups:
Hydrostatic traction drive
Hydrostatic transmission for a stepless vehicle drive which generally operates in a closed circuit with primary control (pump control) or primary and secondary control (pump and motor control). If a suitable
Resolution
change at the measuring device . For variable throttles : The ratio of the change in cross-section (and with it the flow) to the throttle adjustment travel ΔA/Δh.
Digital measured signal
With a digital measured signal the unlimited number of values of the measured variable faces the limited number of values of the measured signal . A value range for the measured variable is therefore assigned
Velocity of sound pressure waves
mineral oil it is dependent on its air content. In pure oil it is approx. 1 500 m/s and drops rapidly with undissolved air in the oil. For this reason an average value of 1 300 m/s is used in the majority
Pilot control behaviour
Provides information on the behaviour of the controlled variable with a changing reference variable , but constant disturbance variable . The controlled variable responds to external effects on the control
Annular area
area of the piston rod Ar St: When performing an accurate force measurement of a hydraulic cylinder with a dual effect and a piston rod on one side ( differential cylinder ) the pressure which may be acting
Variable pump, variable motor
case ( pump control , primary control ). Variable motors are needed for hydrostatic transmissions with secondary adjustment or primary-secondary adjustment as well as for secondary control .
Double acting cylinder
type can be found in almost all fields of application. Double acting cylinders are mostly equipped with a piston rod ( differential cylinder ). However, two piston rods are also fitted ( synchronizing cylinder