Hydraulic drive device with load-dependent pressure distributor

Patent metadata

Field	Value
Publication number	US-10359058-B2
Application number	US-201715426515-A
Country	US
Kind code	B2
Filing date	Feb 7, 2017
Priority date	Feb 10, 2016
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

A hydraulic drive device includes a pump, a hydraulic machine, and a tank. The hydraulic machine is connected fluidically to first and second fluid lines, which are configured to be connected fluidically to the tank or the pump via an adjustable main valve. The device further includes a first valve with a continuously adjustable first orifice. Pressure fluid is configured to be conducted out of the second fluid line via the first orifice and into the tank. The first valve is acted upon in the closing direction of the first orifice by a first spring and acted upon in the opposite direction by the pressure at a control point. The control point is connected fluidically to the tank via a first throttle device, connected via a second throttle device to the first fluid line, and connected to the first fluid line via a third throttle device and a second valve.

First claim

What is claimed is:

1. A hydraulic drive device, comprising:
a pump;
a tank;
a hydraulic machine directly connected fluidically to a first fluid line and a second fluid line;
an adjustable main valve configured optionally to fluidically connect the first and second fluid lines to the tank or the pump; and
a first valve having a continuously adjustable first orifice,
wherein pressure fluid is configured to be conducted out of the second fluid line via the first orifice into the tank,
wherein the first valve is (i) acted upon in a closing direction of the first orifice by a first spring and (ii) acted upon in a direction opposite the closing direction by the pressure at a control point, and
wherein the control point is (i) connected fluidically to the tank via a first throttle device and independent of the main valve, (ii) fluidically connected directly via a second throttle device to the first fluid line, and (iii) fluidically connected to the first fluid line via a third throttle device and a second valve.

2. The hydraulic drive device according to claim 1 , wherein the second valve has an adjustable second orifice, the second valve acted upon by the pressure in the second fluid line in a closing direction of the second orifice.

3. The hydraulic drive device according to claim 2 , wherein the second valve is acted upon by a second spring in an opening direction of the second orifice.

4. The hydraulic drive device according to claim 1 , wherein the third throttle device and the second valve are connected in series.

5. The hydraulic drive device according claim 1 , wherein the first valve is acted upon in the closing direction of the first orifice exclusively by the first spring.

6. The hydraulic drive device according to claim 1 , wherein a flow resistance of one or more of the second throttle device and the third throttle device is dependent on the direction with which the pressure fluid flows through the respective throttle device.

7. The hydraulic drive device according to claim 6 , wherein the flow resistance of the one or more of the second throttle device and the third throttle device from the first fluid line towards the control point is smaller than the flow resistance in the opposite direction.

8. The hydraulic drive device according to claim 6 , wherein the one or more of the second throttle device and the third throttle device in each case comprise two throttle check valves that are connected in series in the opposite direction.

9. The hydraulic drive device according to claim 1 , wherein the first throttle device has a fixed flow resistance.

10. The hydraulic drive device according to claim 1 , wherein:
a first check valve is arranged in the second fluid line, the first check valve exclusively allowing a fluid flow from the main valve to the hydraulic machine, and
the first valve is connected between the first check valve and the hydraulic machine to the second fluid line.

11. The hydraulic drive device according to claim 1 , wherein the hydraulic machine is connected in terms of rotational drive to a cable winch.

Assignees

• Bosch Gmbh Robert

Inventors

• Schuette Michael
• Loewe Peter

Classifications

• F15B2211/761

  Control of a negative load, i.e. of a load generating hydraulic energy · CPC title

• F15B2211/6355

  having valve means · CPC title

• F15B2211/528

  actuated by fluid pressure · CPC title

• F15B2211/5159

  being connected to an output member and a return line · CPC title

• F15B2211/50581

  using counterbalance valves · CPC title