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About this product
Bosch Rexroth AG
, A4VG Series 40, RE 92004-01-B/05.2017
Actuation of the switching solenoid enables pilot pressure through-flow into the
control device of the pump. The pump can be swiveled out. When the solenoid is
de-energized, this connection is interrupted and at the same time the two stroking
chambers are connected to each other and relieved to the pump housing. This
ensures the pump is drive torque-free.
Switching off the control pressure and a bypass circuit for the two stroking
chambers does not ensure that the pump goes to the central position (neutral
position).
▶
Use an appropriate emergency-off device to ensure that the drive can be brought
to a safe position at any time. The machine or system manufacturer is responsible
for the installation of a proper emergency-off device.
The swivel angle of the cradle (
13
) is infinitely variable. Adjusting the swivel angle
changes the piston stroke and therefore, the displacement. Controlling the
swashplate through the neutral position will change the direction of flow (making
reversing operation possible). The swivel angle is controlled hydraulically by the
stroking piston
(
3
)
. The cradle is mounted in swivel bearings for easy motion and
the neutral position is spring-centered. Increasing the swivel angle increases the
displacement; reducing the angle results in a corresponding reduction in
displacement.
Various control devices are available depending on requirements. Information
about this can be found in data sheet 92004.
5.3 Bypass function
For vehicles with hydrostatic travel drive, as long as there is no downstream
mechanical interruption of the drive train (switch to idle/free running), the flow can
be altered using a bypass circuit in order to tow the vehicle out of the immediate
danger zone. Turning the corresponding screw allows the hydraulic fluid to flow
freely.
The bypass function must be deactivated again before restarting the machine.
neutral valve
(optional)
Control