Valve block having a valve assembly

• US 9,874,884 B2
• Filed: 10/15/2014
• Issued: 01/23/2018
• Est. Priority Date: 10/15/2013
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Knapper, Steffen
• Primary Examiner(s): Lopez, F. Daniel
• Assistant Examiner(s): Nguyen, Dustin T
• Application Number:
  US14/515,099
• Publication Number:
  US 20150101676A1
• Time in Patent Office: 1,196 Days
• Field of Search: 60452, 60422, 60468, 60420, 91446, 91448
• CPC Class Codes: F15B 11/165 for adjusting the pump output or bypass in response to demand
• CPC Class Codes: F15B 13/0417 Load sensing elements; Internal fluid connections therefor; Anti-saturation or pressure-compensation valves
• CPC Class Codes: F15B 13/0817 Multiblock manifolds
• CPC Class Codes: F15B 2211/20546 variable capacity
• CPC Class Codes: F15B 2211/30535 the pressure compensating valve is arranged between pressure source and directional control valve
• CPC Class Codes: F15B 2211/3127 Floating position connecting the working ports and the return line
• CPC Class Codes: F15B 2211/6051 having valve means between output member and the load sensing circuit
• CPC Class Codes: F15B 2211/6054 using shuttle valves
• CPC Class Codes: F15B 2211/6055 using pressure relief valves
• CPC Class Codes: F15B 2211/654 the load sensing pressure being lower than the load pressure
• CPC Class Codes: F15B 2211/7142 the output members being arranged in multiple groups
• CPC Class Codes: G05D 16/106 Sleeve-like sensing elements; Sensing elements surrounded by the flow path
• CPC Class Codes: Y10T 137/2544 Supply and exhaust type

Abstract

A valve block includes a plurality of control valve disks that form a first block part and a second block part. A supply pressure for the control valve disks of the first block part is limited by a common pressure-limiting valve. The common pressure-limiting valve is arranged such that a prevailing load pressure registered by the control valve disks does not exceed a specific value. The supply pressure for the control valve disks of the second block part is not limited.

Claims

1. A valve assembly, comprising:

a plurality of control valves, each control valve including a control piston configured to control a direction and speed of a respective consumer connected to the valve assembly, the control piston forming a metering orifice, and the plurality of control valves separated into a first subset of control valves and a second subset of control valves;

a respective pressure compensator assigned to each control valve such that a pressure upstream of the metering orifice and a pressure downstream of the metering orifice of each control valve is signaled to the respective pressure compensator,

each pressure compensator configured to regulate a pressure gradient at the metering orifice of the assigned control valve toward a constant value irrespective of a load of the respective consumer, and

the pressure downstream of the metering orifice of each control valve registered, in each case, to the respective pressure compensator by a respective load-sensing flow path;

a shuttle valve that includes an outlet connection, and that is configured to connect the respective load-sensing flow path of the first subset of control valves having a highest pressure to the outlet connection of the shuttle valve;

a pressure-limiting valve disposed downstream of the outlet connection of the shuttle valve, and configured to limit the highest pressure of the load-sensing flow paths of the first subset of control valves, the second subset of control valves disposed downstream of the pressure-limiting valve such that the pressure limiting valve is disposed between the first subset and the second subset; and

a restrictor disposed in a fluid connection parallel to the pressure-limiting valve.

2. The valve assembly according to claim 1, further comprising a respective restrictor configured to register the pressure downstream of the metering orifice of each control valve.

3. The valve assembly according to claim 1, wherein:

the shuttle valve includes a plurality of shuttle valve units corresponding to the control valves in the first subset of control valves, each shuttle valve unit having a first inlet connection connected to the respective load sensing path of a corresponding control valve;

the shuttle valve units are connected to each other to form a shuttle valve cascade, whereby a second inlet connection of each succeeding shuttle valve unit is connected to an outlet of a preceding shuttle valve unit; and

the outlet of the last shuttle valve unit in the shuttle valve cascade forms the outlet connection of the shuttle valve, and is configured to connect to a variable-capacity pump configured to sense the highest pressure of the load-sensing flow paths of the first subset of control valves.

4. A valve block, comprising:

a valve assembly including;

a plurality of control valve disks, a first subset of the control valve disks forming a first block part and a second subset of the control valve disks forming a second block part downstream of the first block part, each control valve disk having;

a respective control valve with a control piston configured to control a direction and speed of a respective consumer connected to the control valve disk, the control piston forming a metering orifice of the respective control valve; and

a respective pressure compensator assigned to the respective control valve such that a pressure upstream of the metering orifice and a pressure downstream of the metering orifice of the respective control valve is signaled to the respective pressure compensator,

each pressure compensator configured to regulate a pressure gradient at the metering orifice of the assigned control valve toward a constant value irrespective of a load of the respective consumer, and

the pressure downstream of the metering orifice of the respective control valve registered, in each case, to the respective pressure compensator by a respective load-sensing flow path;

a shuttle valve that includes an outlet connection, and that is configured to connect the respective load-sensing flow path of the control valve disks in the first block part having a highest pressure to the outlet connection of the shuttle valve; and

a pressure limiting valve disk positioned between the first block part and the second block part;

the pressure limiting valve disk having a pressure-limiting valve disposed downstream of the outlet connection of the shuttle valve, and configured to limit the highest pressure of the load-sensing flow paths of the control disks in the first block part.

5. The valve block according to claim 4, further comprising a pump part connected to the second block part or the pressure-limiting valve disk.

6. The valve block according to claim 4, further comprising an end piece connected to the first block part.

7. The valve block according to claim 4, wherein the shuttle valve includes a plurality of shuttle valve units such that each control valve disk in the first block part includes a respective shuttle valve unit;

the respective shuttle valve unit of each control valve disk in the first block part having a first inlet connection connected to the respective load-sensing flow path of the respective control valve, a second inlet connection connected to a respective first connection side of the control valve disk, and an outlet connection connected to a second connection side of the control valve disk.

8. The valve block according to claim 7, further comprising:

a pump part connected to the second block part or the pressure-limiting valve disk;

wherein the pressure-limiting valve disk includes a passage extending between a first connection side of the pressure-limiting valve disk and a second connection side of the pressure-limiting valve disk and forming a fluid connection between (i) the outlet connection of the shuttle valve unit of an outer-most control valve disk of the control valve disks in the first block part and (ii) an adjacent control valve disk of the second block part or the pump part.

9. The valve block according to claim 4, wherein each of the control valve disks are of identical configuration.

10. The valve block according to claim 4, wherein the control valve disks and the pressure-limiting valve disk form a common inlet port, a common outlet port, a common control fluid inlet port, and a common control fluid outlet port.

11. The valve block according to claim 4, wherein each of the control valve disks includes two working connections that are connected to the respective control valve via a feed port and a return port.

12. The valve assembly of claim 4, wherein the pressure limiting valve disk further includes a restrictor disposed in a fluid connection parallel to the pressure-limiting valve.

13. The valve assembly of claim 4, wherein each control valve disk further has a respective restrictor configured to register the pressure downstream of the metering orifice of the respective control valve.

14. A valve assembly, comprising:

a plurality of control valve disks, each control valve disk configured to connect to a respective consumer and including;

a control piston configured to control a direction and speed of the respective consumer;

a pressure compensator configured to regulate a pressure gradient for the respective consumer toward a constant value irrespective of a load of the respective consumer; and

a shuttle valve connected to the pressure compensator and configured such that, in a configuration whereat multiple control valve disks are positioned in a stack, the shuttle valve of a control valve disk at a bottom of the stack outputs a highest pressure of the pressure compensators of the control valve disks in the stack; and

a pressure limiting valve disk that includes a pressure limiting valve configured such that, in a configuration whereat the pressure limiting valve disk is positioned within a stack of control valve disks, the pressure limiting valve;

limits a maximum pressure for the highest pressure of the pressure compensators for control valve disks positioned above the pressure limiting valve disk in the stack, and

does not limit pressures of pressure compensators of control valve disks positioned below the pressure limiting valve disk in the stack.

15. The valve assembly of claim 14, further comprising:

a valve block configured to interchangeably receive the plurality of control valve disks and the pressure limiting valve disk in different stacked orders.