ROTATIVE ACTION ALLHYDRAULIC DRIVE WITH VALVE DISTRIBUTION AND SPEED CONTROL Russian patent published in 2017 - IPC F15B11/04 

FIELD: engines and pumps.

SUBSTANCE: allhydraulic drive comprises a pump (9) with a discharge flow line (8) connected via a flow regulator (12) to the drain (tank), a reversible hydraulic motor (1) with a working lift flow line (14) and a lowering flow line (17), kinematically connected to an actuator (not shown) provided with a hydro-controlled brake. In the working lowering flow line (17) of the hydraulic motor (1), a retaining device (19) is installed, and in the working lift flow line (14) of the hydraulic motor (1) there is a retaining device (18). The retaining device (18) includes a retaining valve (2) connected by the inlet to the lift flow line (14) and to one of the hydraulic motor (1) cavities, and a check valve (4) connected to this hydraulic motor cavity by the outlet. The retaining device (19) includes a retaining valve (3) connected by the inlet to the lift flow line (17) and to one of the hydraulic motor (1) cavities, and a check valve (5) connected to this hydraulic motor cavity by the outlet. Retaining devices (18, 19) are interconnected via further check valve (25) and a hydraulic on off normally closed bilinear spring-loaded switch (24) by check valves inputs (4, 5) and the retaining valves (2, 3) outputs, the pumping (9) flow line (8) is connected to an input of each of the retaining devices (18, 19) check valves (4, 5) through one of two mounted in parallel electrically controlled three-way two-position spring-loaded valves (10, 11) each connected to the discharge flow line (8) and the input of the noted regulator (12) of consumption by its normally closed flow line. Each retaining device (18 and 19) is equipped with a throttle (6 or 7) respectively, connected in parallel with the check valve (4, 5) and the retaining valve (2, 3). The retaining device (18) in the lift flow line (14) is provided with a hydraulic lock (15) installed in series with the throttle (6) and a connected by control cavity (16) to the lowering flow line (17) and connected through the noted additional non-return valve (25) hydraulically controlled brake retraction chamber.

EFFECT: increased smoothness of the hydraulic motor operation when it is moving off from the rest and moving at a low speed, reducing the value of this minimum speed.

8 cl, 1 dwg