Valve arrangement

1. A valve system for activating a piston of a piston-cylinder arrangement, the piston being configured to activate a movable contact piece of a high-voltage power switch, the valve system comprising:

a pilot control valve including 3/2-way valve; and

a main valve arrangement including a first main valve and a second main valve,

wherein the first and second main valves include 2/2-way valves,

wherein in a first position the pilot-control valve is configured to move the first main valve into an open position so as to direct a path for a high pressure fluid to a space above the piston,

wherein in a second position the pilot-control valve is configured to connect the space to a low-pressure tank so as to relieve a pressure in the space above the piston via the second main valve,

wherein the pilot-control valve is configured to open the second main valve and configured to close the first main valve,

wherein the first and the second main valves each include

a valve body,

a slide, which is displaceably arranged within the valve body, and

a plurality of control faces, wherein each control face comprises one or more annular surfaces,

wherein a pressurized fluid is configured to be applied to the plurality of control faces,

wherein the plurality of control faces include a first control face and a second control face acting on the slide in one direction and a third control face acting on the slide in another direction, such that a sum of a force from the first control face and a force from the second control face is equal to a force from the third control face, and

wherein the first control face of the second main valve includes a first and a second end face and is connected to the low-pressure tank.

2. The valve system as recited in claim 1 , wherein each of the plurality of control faces correspond to an actuation element, such that a surface area ratio of the third control face to the second control face of the second main valve is always greater than a surface area ratio of the third control face to the first control face of the first main valve.

3. The valve system as recited in claim 1 , wherein the second control face of the second main valve is formed by an annular face disposed on the slide and connected to the pilot-control valve.

4. The valve system as recited in claim 1 , wherein the high-pressure fluid is configured to be applied alternately to the first and third control faces of the first main valve via the pilot-control valve, and

wherein the high-pressure fluid is configured to be applied alternately to the first and third control faces of the second main valve via the pilot-control valve.

5. The valve system as recited in claim 1 , wherein the first control face of the first main valve is continuously connected to a high pressure via a high-pressure feed line, and

wherein the first control face of the second main valve is continuously connected to a low pressure.

6. The valve system as recited in claim 1 , wherein a high pressure is configured to be applied to the second control faces of the first and the second main valves when the first main valve is opened and the second main valve is closed, and

wherein a low pressure is configured to be applied to the second control faces of the first and the second main valves when the first main valve is closed and the second main valve is opened.

7. The valve system as recited in claim 1 , wherein each of the first and the second main valves contain a helical compression spring acting on the slide in a closing direction.

8. The valve system as recited in claim 1 , wherein the slide of the second main valve includes a longitudinal bore passing completely through the slide such that a space accommodating the helical spring is connected to the first end face and to the low-pressure tank.

9. The valve system as recited in claim 1 , wherein the slide of the first main valve has a longitudinal bore passing partially through the slide and connecting a space accommodating the helical compression spring to a duct in an interior of the first main valve, wherein the duct is connected to the piston-cylinder arrangement.

10. The valve system as recited in claim 1 , wherein each of the plurality of control faces are formed by at least one of a radially extending annular face and a radially extending end face disposed on the slide.

11. The valve system as recited in claim 10 , wherein the third control face of the first main valve is formed by a first end face and is connected to the pilot-control valve.

12. The valve system as recited in claim 10 , wherein the first and second control faces of the first main valve are formed by a plurality of annular faces integrally formed on the slide and by the end face.

13. A valve system for activating a piston of a piston-cylinder arrangement for a hydraulic or fluid device, the valve system comprising:

a pilot control valve including a 3/2-way valve; and

a main valve arrangement including a first main valve and a second main valve,

wherein the first and second main valves include 2/2-way valves,

wherein in a first position the pilot-control valve is configured to move the first main valve into an open position so as to direct a path for a high pressure fluid to a space above the piston,

wherein in a second position the pilot-control valve is configured to connect the space to a low-pressure tank so as to relieve a pressure in the space above the piston via the second main valve,

wherein the pilot-control valve is configured to open the second main valve and configured to close the first main valve,

wherein the first and the second main valves each include

a valve body,

a slide, which is displaceably arranged within the valve body, and

a plurality of control faces,

wherein each control face comprises one or more annular surfaces,

wherein a pressurized fluid is configured to be applied to the plurality of control faces,

wherein the plurality of control faces include a first control face and a second control face acting on the slide in one direction and a third control face acting on the slide in another direction, such that a sum of a force from the first control face and a force from the second control face is equal to a force from the third control face, and

wherein each of the plurality of control faces correspond to an actuation element, such that a surface area ratio of the third control face to the second control face of the second main valve is always greater than a surface area ratio of the third control face to the first control face if the first main valve.

14. The valve system as recited in claim 13 , wherein the second control face of the second main valve is formed by an annular face disposed on the slide and connected to the pilot control valve.

15. The valve system as recited in claim 13 , wherein the first control face of the second main valve includes a first and a second end face and is connected to the low-pressure tank.

16. The valve system as recited in claim 13 , wherein the high-pressure fluid is configured to be applied alternately to the first and third control faces of the first main valve via the pilot-control valve, and

wherein the high-pressure fluid is configured to be applied alternately to the first and third control faces of the second main valve via the pilot-control valve.

17. The valve system as recited in claim 13 , wherein the first control face of the first main valve is continuously connected to a high pressure via a high-pressure feed line, and

wherein the first control face of the second main valve is continuously connected to a low pressure.

18. The valve system as recited in claim 13 , wherein each of the plurality of control faces are formed by at least one of a radially extending annular face and a-radially extending end face disposed on the slide.

19. The valve system as recited in claim 18 , wherein the third control face of the first main valve is formed by a first end face and is connected to the pilot-control valve.

20. The valve system as recited in claim 18 , wherein the first and second control faces of the first main valve are formed by a plurality of annular faces integrally formed on the slide and by the end face.