Switching methods for hydraulic pumps
circuits ). Series circuit : Pump 1 leads to pump 2. This circuit is used to improve the filling of a high-pressure pump or to reach a higher output pressure at pump 2 (e.g. in the case of some internal
Two edge control
1. Hydraulic resistance control for a displacement chamber with a type A hydraulic half bridge (adjustable input and output resistance); use of both control edges of a continuously adjustable 3/2-way [...] bridge D), the two edge control enables movement control. One example is the copier system in ( Figure Z 15 ). However, the maximum useful cylinder force is only the rod surface area. In this form, the two-edge [...] another. However, it does not achieve the force gain and accuracy of a valve control with four edges . 2. Hydraulic resistance control for an actuator with two displacement chambers by two hydraulic half bridges
Flip flop
Fast, bistable memory element for saving 1 bit. A number of flip flops connected in series are used as a shift register.
Hydraulic motor
the rotation speed n 2 is only dependent on the flow rate Q 1 introduced and the displacement V 2: while the torque M 2 is determined by the load pressure p L and the displacement V 2: In general, all pumps
Hydraulic bridge rectifier
1. Arrangement whereby a combination of two half bridges results in a full (Wheatstone) bridge. This is the case, for example, with the control edges of continuously adjustable valves whereby deflecting [...] spool creates two adjustable orifices between which the motor (cylinder) is located (Figure H 15) . 2. Arrangement whereby the four are arranged in a kind of rectifier circuit in such a way, for example
DC solenoid
primarily operate with 24 V, a transformer and rectifier are required. It is possible to accelerate the increase in current by means of fast excitation or by means of over-excitation (Figure G 19) . In relation [...] initially increases more slowly, and it therefore switches more slowly than the AC solenoid (Figure G 18) . Advantages : Given corresponding design, very high switching figures are also possible, The armature [...] section for reasons related to the magnetic flux. The armature axis does not need to be sealed (Figure G 20) . This design is primarily used these days.
Stiction of seals
Friction of seals to be overcome at the start of a movement (Figure H 1) . It is dependent on both the form of the seal (preload) and the seal material and on the service life of the seal: during longer [...] inactivity, the oil film under the seal is squeezed away allowing dry friction to predominate (Figure H 2) . Stiction of seals is particularly evident during stick-slip movements and during oscillating movements
Response sensitivity
stated in mA or in % of the nominal current (DIN 24 311). The term can best be explained using digital technology: A five-stage digital valve has 25—1 = 31 steps between zero and maximum, i.e. a resolution
Arithmetic mean, average
arithmetic mean or the average of a series of measurements with n independent individual values x, 1 ... x n, termed x̄ for short, is defined by (VDI-VDE 2600).
HL oils
subjected to a high thermal load. Viscosity index 95 to 105. (requirement standard DIN 51 524, Part 1).