Valve arrangement
The invention concerns a valve arrangement ( 1 ) with a high-pressure connection (P), a low-pressure connection (T), at least one control valve ( 2 to 5 ), which is accommodated in a control valve module and has at least one working connection (A, B) for a hydraulic consumer ( 7 to 10 ), and a safety valve ( 6 ), which is accommodated in a safety valve module, and which releases or blocks a passage between the high-pressure connection (P) and the control valves ( 2 to 5 ), the control valve module ( 2 to 5 ) and the safety valve module ( 6 ) being connected to one component group. It is endeavoured to provide a valve arrangement with a high safety level. For this purpose, it is ensured that each control valve ( 2 to 5, 2 ′ to 5 ′) has an error detection device ( 19 ), that the safety valve module ( 6 ) has a safety switch device ( 21 ) and that the component group has a connection ( 20 ) between the safety switch device ( 21 ) and the error detection device ( 19 ).
1. A valve arrangement with a high-pressure connection, a low-pressure connection, at least one control valve, which is accommodated in a control valve module and has at least one working connection for a hydraulic consumer, and a safety valve, which is accommodated in a safety valve module, and which releases or blocks a passage between the high-pressure connection and the control valves, the control valve module and the safety valve module being connected to one component group, wherein each control valve has an error detection device, that the safety valve module has a safety switch device and that the component group has a connection between the safety switch device and the error detection device.
2. The valve arrangement according to claim 1 , wherein the connection has a connection (F) that is led to the outside.
3. The valve arrangement according to claim 1 , wherein the connection is a signal transmission wire, which is looped through from one control valve to the other and to the safety valve.
4. The valve arrangement according to claim 1 , wherein a self-test device is provided, which tests the connection on the occurrence of a predetermined event.
5. The valve arrangement according to claim 4 , wherein the predetermined event is the beginning of a supply with electrical energy.
6. The valve arrangement according to claim 4 , wherein the self-test device tests the error detection device and/or the safety switch device.
7. The valve arrangement according to claim 4 , wherein the self-test device is located in the safety valve module.
8. The valve arrangement according to claim 4 , wherein in the error-free case each control valve provides a test signal with additional information.
9. The valve arrangement according to claim 8 , wherein the additional information is formed by a prolongation of an impulse.
10. The valve arrangement according to claim 1 , wherein the connection is formed in a cable, which is led along the outside of the component group.
11. The valve arrangement according to claim 1 , wherein the error detection device has a position sensor, which determines the position of a valve element, and a comparator, which compares the determined position with a desired value, a predetermined deviation causing the generation of an error signal.
12. The valve arrangement according to claim 11 , wherein the error detection device generates a neutral position signal, when the valve element is in its neutral position, and the safety valve doses the passage from the high-pressure connection (P) to the control valves, when all valve elements are in the neutral position.