Hydraulic steering arrangement
A hydraulic steering arrangement ( 1 ) is described comprising a supply port arrangement (P, T) having a pressure port (P) and a tank port (T), a working port arrangement having two working ports (L, R), a main flow path ( 2 ) having a main orifice (A 1 ), at least one further orifice (A 2 , A 3 , A 4 ) downstream the main orifice (A 1 ), and a measuring motor ( 3 ), the main flow path ( 2 ) being arranged between the pressure port (P) and the working port arrangement (L, R), a return flow path ( 4 ) arranged between the working port arrangement (L, R) and the tank port (T), an amplification flow path ( 6 ) having an amplification orifice (A U ) and being arranged between the pressure port (P) and the working port arrangement (L, R), and an adjustable pressure source ( 9 ) connected to the pressure port (P) and having a load sensing port ( 18 ), wherein a main drain orifice (A md ) is connected between the main flow path ( 2 ) downstream the main orifice (A 1 ) and the return flow path ( 4 ). It should be possible to operate such a steering arrangement with a dynamic flow. To this end a flow divider ( 19 ) connects the load sensing port ( 18 ) with the main flow path ( 2 ) downstream the main orifice (A 1 ) and the amplification flow path ( 6 ) downstream the amplification orifice (A U ).
1. A hydraulic steering arrangement comprising a supply port arrangement (P, T) having a pressure port (P) and a tank port (T), a working port arrangement having two working ports (L, R), a main flow path having a main orifice (A 1 ), at least one further orifice (A 2 , A 3 , A 4 ) downstream the main orifice (A 1 ), and a measuring motor, the main flow path being arranged between the pressure port (P) and the working port arrangement (L, R), a return flow path arranged between the working port arrangement (L, R) and the tank port (T), an amplification flow path having an amplification orifice (A U ) and being arranged between the pressure port (P) and the working port arrangement (L, R), and an adjustable pressure source connected to the pressure port (P) and having a load sensing port, wherein a main drain orifice (A md ) is connected between the main flow path downstream the main orifice (A 1 ) and the return flow path, wherein a flow divider connects the load sensing port with the main flow path downstream the main orifice (A 1 ) and the amplification flow path downstream the amplification orifice (A U ).
2. The steering arrangement according to claim 1 , wherein the flow divider is connected to a point between the main orifice (A 1 ) and the main drain orifice (A md ).
3. The steering arrangement according to claim 1 , wherein an amplification drain orifice (A ad ) is connected between the flow divider and the tank.
4. The steering arrangement according to claim 3 , wherein a relation of opening behaviour of the main drain orifice (A md ) and the amplification drain orifice (A ad ) corresponds to a relation of the opening behaviour of the main orifice (A 1 ) and the amplification orifice (A U ).
5. The steering arrangement according to claim 1 , wherein a check valve is arranged in a connection between the flow divider and the main flow path, the check valve opening in a direction away from the flow divider.
6. The steering arrangement according to claim 1 , wherein the main drain orifice (A md ) and the amplification drain orifice (A ad ) start throttling before the main orifice (A 1 ) and the amplification orifice (A U ) start opening.
7. The steering arrangement according to claim 1 , wherein a safety valve is arranged in the amplification flow path, said safety valve being loaded in closing direction by a pressure in the main flow path upstream the measuring motor and downstream the main orifice (A 1 ).
8. The steering arrangement according to claim 2 , wherein an amplification drain orifice (A ad ) is connected between the flow divider and the tank.
9. The steering arrangement according to claim 2 , wherein a check valve is arranged in a connection between the flow divider and the main flow path, the check valve opening in a direction away from the flow divider.
10. The steering arrangement according to claim 3 , wherein a check valve is arranged in a connection between the flow divider and the main flow path, the check valve opening in a direction away from the flow divider.
11. The steering arrangement according to claim 4 , wherein a check valve is arranged in a connection between the flow divider and the main flow path, the check valve opening in a direction away from the flow divider.
12. The steering arrangement according to claim 2 , wherein the main drain orifice (A md ) and the amplification drain orifice (A ad ) start throttling before the main orifice (A 1 ) and the amplification orifice (A U ) start opening.
13. The steering arrangement according to claim 3 , wherein the main drain orifice (A md ) and the amplification drain orifice (A ad ) start throttling before the main orifice (A 1 ) and the amplification orifice (A U ) start opening.
14. The steering arrangement according to claim 4 , wherein the main drain orifice (A md ) and the amplification drain orifice (A ad ) start throttling before the main orifice (A 1 ) and the amplification orifice (A U ) start opening.
15. The steering arrangement according to claim 5 , wherein the main drain orifice (A md ) and the amplification drain orifice (A ad ) start throttling before the main orifice (A 1 ) and the amplification orifice (A U ) start opening.
16. The steering arrangement according to claim 2 , wherein a safety valve is arranged in the amplification flow path, said safety valve being loaded in closing direction by a pressure in the main flow path upstream the measuring motor and downstream the main orifice (A 1 ).
17. The steering arrangement according to claim 3 , wherein a safety valve is arranged in the amplification flow path, said safety valve being loaded in closing direction by a pressure in the main flow path upstream the measuring motor and downstream the main orifice (A 1 ).
18. The steering arrangement according to claim 4 , wherein a safety valve is arranged in the amplification flow path, said safety valve being loaded in closing direction by a pressure in the main flow path upstream the measuring motor and downstream the main orifice (A 1 ).
19. The steering arrangement according to claim 5 , wherein a safety valve is arranged in the amplification flow path, said safety valve being loaded in closing direction by a pressure in the main flow path upstream the measuring motor and downstream the main orifice (A 1 ).
20. The steering arrangement according to claim 6 , wherein a safety valve is arranged in the amplification flow path, said safety valve being loaded in closing direction by a pressure in the main flow path upstream the measuring motor and downstream the main orifice (A 1 ).