RE 30011-B, Edition 10.2021, Bosch Rexroth AG
Product description |
Pressure and flow control system SYDFE1 series 2X, 3X
17/96
are processed in the control electronics and compared with the given command
values. A minimum value comparator ensures that automatically only the controller
assigned to the desired working point is active. In this process, one system
variable (pressure, swivel angle or - optionally - power) is exactly corrected, the
other two system variables are below the given command value. The output signal
of the minimum value comparator becomes the command value for the valve
control loop.
The actual value of the valve spool position is sensed using an inductive position
transducer (
6
). The output value of the valve position controller determines via the
amplifier output stage the current through the proportional solenoid (
8
). As soon
as the working point is reached the control spool (
9
) of the proportional valve is
held in the centered position.
When the higher-level controllers demand an increase in the swivel angle (increase
in flow), the valve spool (
9
) must be moved away from the central position
(connection of the actuating piston (
4
) A → T) until the swivel angle has reached
the required value. The movement of the valve spool against the force of the spring
(
10
) is achieved by a corresponding increase in the electrical current through the
proportional solenoid (
8
).
A reduction of the swivel angle (reduction in flow) is achieved by connecting the
actuating piston (
4
) from P → A.
Since the introduction of A10VSO, series 32, a so-called pre-compression volume
(
14
) PCV has been available as an optional extra. This variant (feature “32” in the
ordering code for the design of the subplate) is an integral part of the subplate
and cannot be retrofitted.
The PCV reduces pressure pulsation and can contribute to an improvement in
the generation of noise and render secondary measures for pulsation reduction
unnecessary. This technology is, however, not employed in the subplate variant
without PCV (feature “22” in the ordering code).
The actuating system of the pump can be supplied with pilot oil in three different
ways:
1.
Internal, without pre-load valve (only possible for operating pressures
>12...20 bar, see chapter 5.5.1 “Internal/external pilot oil“ on page 25).
2.
Internally, with pre-load valve (operating pressure 0…100 %).
3.
External supply via a shuttle valve - automatic changeover between internal/
external via a shuttle valve sandwich plate (see “External pilot oil supply“ on
page 26).
Pre-compression volume
PCV
Actuating system supply
