Hydraulic power pack with load sensing variable displacement pump and constant displacement pump
8.2
Function
The hydraulic power pack is suitable for all basic experiments in mobile hydraulics. Both pumps are
powered by a single electric motor. The controllable axial piston pump has a load-sensing pump controller.
The constant displacement pump is protected by a pressure relief valve. The motor-pump unit is located on
top of the tank. There's a return filter in the return line to the tank. The tank vent is also filtered. The oil level
can be read at the sight glass with temperature indicator.
The motor is switched on and off with an on/off switch. The motor is protected against overloading and is
secured against restart after power failure.
The electric motor (14) is mounted to the top of the tank (29). The pumps are screwed onto the motor via the
bellhousing. The axial piston pump (18) is equipped with a drive shaft in order to be able to power the
downstream gear pump (6) as well.
The pumps draw in oil from the tank (3) via intake pipes.
The axial piston pump is equipped with a load-sensing pump controller (11).
The gear pump is protected by a pressure relief valve (9). In the event that pressure relief is required,
hydraulic oil flows back to the tank via the tank line (4).
The pressure of the delivered hydraulic oil is indicated at the pressure gauge (5).
The leakage oil line (10) for the vane pump is transparent so that air bubbles can be seen.
The return flow from the consuming device is connected to the collecting block via the connection fitting
(22). The blue coupling sockets (23) are intended for the connection of pressure-free return lines. The blue
coupling sockets (23) are not for the connection of compressed air! The oil flows from the collection block
back to the tank via the return filter (25).
Two additional connections (21) are included directly on the tank which are used to connect the discharge
measurement container.
The fill-level and hydraulic oil temperature can be read at the sight glass (2).
The vent filter (20) equalizes air pressure in the reservoir in the event of a fluctuating hydraulic oil level. Air
passing through the filer is filtered at the same time.
In order to fill the power pack, either the filter cover (24) is unscrewed and the filter cartridge is removed, or
the vent filter (20) is removed. The hydraulic oil in the tank can be drained via the tank drain plug (1).
21
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