About this product 19/60
RE 92801-01-B/11.2018, A15VSO/A15VLO Series 11,
Bosch Rexroth AG
5.2.2 Functional description
Torque and rotational speed are applied to the drive shaft (
) by a drive motor. The
drive shaft is connected to the cylinder (
) by splines, causing the cylinder to rotate.
With every revolution, the pistons (
) perform a stroke in the cylinder bores, the
size of which depends on the pitch of the cradle (
) are held
on with the pistons and guided along the glide surface of the cradle by the retaining
plate (
2
). The pitch of the swashplate during a revolution causes each piston to move
over the bottom and top dead centers and back to its initial position. Hydraulic fluid
is fed into and out through two control slots in the control plate (
) according
to displacement. Hydraulic fluid flows into the piston chamber as the piston recedes
on the suction side (
). At the same time, the hydraulic fluid is pushed out
of the cylinder chamber into the hydraulic system by the pistons on the high-
pressure side (
).
The swivel angle of the cradle (
) is infinitely variable. Controlling the swashplate
swivel angle changes the piston stroke and, therefore, the displacement. The swivel
angle is controlled hydraulically by means of the stroking piston. The cradle
is mounted in swivel bearings for smooth operation, and it is kept in balance
by the opposed piston (not illustrated). Increasing the swivel angle increases the
displacement; reducing the angle reduces displacement accordingly.
Various control devices are available depending on requirements. Information
about this can be found in data sheet 92801.
The axial piston unit A15VLO is equipped with a charge pump (
). The charge pump
(impeller) is a centrifugal pump with which the pump is filled and can be operated
at higher rotational speeds. This also simplifies cold starting at low temperatures
and high viscosity of the hydraulic fluid. Externally increasing the inlet pressure
is therefore unnecessary in most cases. Charging the reservoir with compressed air
is not permissible.
M
A
A P
V
g min
V
g max
S
M
T
2
T
3
T
1
4
Fig. 3: Circuit diagram A15VLO with charge pump
Pump function
Control
Charge pump (optional)
