Slave piston principle
moving coil controller or on the rotary servo valve for a torque amplifier . The slave piston principle can also be of electrical design if the pilot element and the main control piston are connected with a
Variable delivery flow (control)
changes the delivery flow in accordance with an input variable. On the pump this is a distance s that can be specified in various ways (Figure F 29) . This process takes place in the function in a control
Throttle forms
each have a pre-defined bore. There are also adjustable throttles with a changing cross-section that can have different forms and therefore different pressure flow characteristics . In addition, the throttle
Digital control
controlled. They are therefore also called discontinuous controls. By selecting the step width they can, however, be adapted to almost all continuity and accuracy requirements.
Digital signals
parameter where each value range is assigned as a whole to a specific item of information. Digital signals can also have multiple parameters (DIN 19 226). In control technology digital signals are only used with
Thermodynamic measuring
balances. It does not depend on the performance variables of the system. Thermodynamic measurements can be used to calculate not only the total efficiency of hydraulic systems, but also offer the option
Jet pipe amplifier
servo valves , which is based on the conversion of kinetic energy to static energy. A jet pipe, which can be actuated by an electro-mechanical converter (e.g. torque motor), distributes (in rest position)
Electric-hydraulic analogy
technology, in particular the significance of hydraulic resistances (Table A 2) . These analogies can be used even on circuit diagrams and in some circumstances form the basis for bond graphs (Figure A
Stiction of seals
oscillating movements where the stroke remains within the height of the seal. No new lubricating film can develop during this kind of movement, which means the whole process is affected by dry friction.
Pitot-static tube
where the pressure difference is able to emerge. This difference between total and static pressure can be used to infer the flow velocity. The pitot-static tube is only slightly dependent on direction.