Round sealing rings
Collective term for seals with a round or almost round cross section. The most important is the O-ring. Another is the Quad-ring along with others within this group ( Figure R 40 ).
Impressed flow
The flow rate in a hydraulic system with a variable pump and appropriate adjustment corresponds to the requirements in accordance with which the adjustment functions. The term impressed, i.e. pre-defined [...] term " constant flow system " often used is not correct here, as the flow is not constant. The system with impressed flow is also termed a "(constant) flow source".
Oil hydraulics
Area of hydraulics which works with mineral oil or oil-like hydraulic fluids whose key characteristics are sufficient viscosity coupled with good lubricating performance. All devices used in oil hydraulics [...] these two characteristics. Above all, they favour the widespread use of gap seals , including those with short seal lengths, which means the components used in oil hydraulics can be designed to be relatively
Secondary adjustment of hydrostatic transmissions
A hydrostatic transmission with secondary adjustment works with an impressed flow ( constant current network ) and has a constant pump and a variable motor, which performs the torque setting itself. This [...] an increasing rotation speed and –– theoretically –– a constant output (this should not be confused with secondary control !) ( Figure S 44 ).
Pressure independent flow control
throttle function ( throttle valve , continuous directional valve) with a (control throttle) that provides a load pressure independent flow rate with a magnitude defined by the throttle position.
Constant pressure system
really the case with: controls with throttles whereby constant pressure is maintained by allowing any oil flow not required to flow away via the pressure-limiting valve ; variable pump with pressure controller [...] controller which adjusts its delivery flow in line with consumption so the pressure in the system is kept constant. Systems with hydraulic accumulators are also referred to as constant pressure systems, although [...] (Figure K 29) , although they offer the advantage that loads connected in parallel can also be operated with one pump at the same time (e.g. parallel circuit ). In the field of electro-hydraulic control technology
Leakage, leak
in spite of seals , particularly in systems with purely metallic seals, without contributing any useful work. Apart from the geometric variables associated with the site of the leak, the size of any leakage [...] as well as the viscosity of the medium escaping. With leakage from an eccentric ring gap (flow within gaps) of the kind associated, for example, with piston pumps and valve control spools, the following [...] pressure line to the return line where sealed working lines are involved. With continuously adjustable directional valves, it changes with the input signal and reaches its highest level at hydraulic zero (see
Position measurement process
either with coded rulers or with ultrasound. For processes with rulers (e.g. graded glass rulers) a distinction is made between incremental and digital absolute systems. For cylinder drives with position [...] processes ( Figure W 6 ). In analogue position measurement processes, the resistance position measurement (with potentiometer) is commonly used for lengths of up to around 1 m and inductive position measurement
Analogue control
signals in the signal processing and that also uses with progressive function elements. An example is the analogue position control shown in (Figure A 17) with absolute measuring procedure (inductive position
Technical cybernetics
Deals with the theoretical observation of the dynamic behaviour of technical systems in the broadest sense. For example, as a technical system with a certain dynamic performance, which is highly non-linear [...] state changes. However, cybernetics deals not only with system theory, but also the control and feedback control characteristics of these processes, i.e. with their internal transfer and processing of information