Valve assembly for switching and/or regulating a medium flow of an aerospace engine and aerospace engine

1. A valve assembly configured to switch or regulate a medium flow of an aerospace engine, the valve assembly comprising:

a drive, which has one or more electrically actuatable actuators, which are configured to change their length in a direction of a longitudinal axis of the valve assembly when a control voltage is applied to the one or more electrically actuatable actuators;

a valve, which comprises a valve member and a valve piston configured to move back and forth along the longitudinal axis by the drive; and

a flexible separator element, which delimits a working space of the valve from the drive and hermetically separates the drive from the medium flowing through the valve or present in the working space,

wherein the piston plate of the valve piston is disposed in a housing shoulder extending in a direction of a drive housing and which is connected to the working space with its open end,

when the valve is opened the piston plate moves away from the working space in a direction of a shoulder plate,

a first spring is disposed between the shoulder plate and the piston plate, and

the first spring presses the valve member against a valve seat when a voltage is not applied to the one or more electrically actuatable actuators.

2. The valve assembly of claim 1 , wherein the flexible separator element surrounds the valve piston and is connected fluid-tight to the valve piston with a drive-sided end.

3. The valve assembly of claim 1 , wherein the valve piston has a piston plate, extending perpendicular to the longitudinal axis of the valve assembly in a plane, with the flexible separator element being connected to the piston plate with the drive-sided end.

4. The valve assembly of claim 1 , wherein the flexible separator element is connected to a housing component of the drive or to a housing component of the valve with a valve-sided end.

5. The valve assembly of claim 1 , wherein the flexible separator element is a metal bellows or a diaphragm.

6. The valve assembly of claim 1 , wherein the one or more electrically actuatable actuators is a piezo actuator configured to change its length when a voltage is applied to the one or more electrically actuatable actuators.

7. The valve assembly of claim 1 , wherein the one or more electrically actuatable actuators is supported at one end by a housing component, which is adjacent to the valve and is a part of the drive, or by a housing component of the valve.

8. A valve assembly configured to switch or regulate a medium flow of an aerospace engine, the valve assembly comprising:

a drive, which has one or more electrically actuatable actuators, which are configured to change their length in a direction of a longitudinal axis of the valve assembly when a control voltage is applied to the one or more electrically actuatable actuators;

a valve, which comprises a valve member and a valve piston configured to move back and forth along the longitudinal axis by the drive; and

a flexible separator element, which delimits a working space of the valve from the drive and hermetically separates the drive from the medium flowing through the valve or present in the working space,

wherein the one or more electrically actuatable actuators is supported at a second end by a head plate, which is biased by a second spring, wherein the second spring applies a spring bias to the one or more electrically actuatable actuators.

9. The valve assembly of claim 8 , wherein

a valve piston head engages with the head plate,

the valve piston is guided through a bore of the head plate, and

the valve piston head is connected to the valve piston on a side that is opposite the one or more electrically actuatable actuators.

10. The valve assembly of claim 1 , wherein the valve member is a ball.

11. The valve assembly of claim 1 , further comprising:

a device configured to determine an axial displacement of the valve piston, wherein the device outputs a determined stroke to control the one or more electrically actuatable actuators.

12. The valve assembly of claim 1 , wherein the one or more electrically actuatable actuators is arranged in such a way that when a voltage is applied to the one or more electrically actuatable actuators, the one or more electrically actuatable actuators causes the valve to open due to an elongation; and, when no voltage is applied to the one or more electrically actuatable actuators, the one or more electrically actuatable actuators closes the valve.

13. An aerospace engine, comprising:

at least one valve assembly configured to switch or regulate a medium flow of the aerospace engine, wherein the valve assembly comprises

a drive, which has one or more electrically actuatable actuators, which are configured to change their length in a direction of a longitudinal axis of the valve assembly when a control voltage is applied to the one or more electrically actuatable actuators;

a valve, which comprises a valve member and a valve piston configured to move back and forth along the longitudinal axis by the drive; and

a flexible separator element, which delimits a working space of the valve from the drive and hermetically separates the drive from the medium flowing through the valve or present in the working space,

wherein the one or more electrically actuatable actuators is supported at a second end by a head plate, which is biased by a second spring, wherein the second spring applies a spring bias to the one or more electrically actuatable actuators.

14. The aerospace engine of claim 13 , the valve assembly further comprising:

a valve piston head engages with the head plate,

the valve piston is guided through a bore of the head plate, and

the valve piston head is connected to the valve piston on a side that is opposite the one or more electrically actuatable actuators.

15. An aerospace engine, comprising:

at least one valve assembly configured to switch or regulate a medium flow of the aerospace engine, wherein the valve assembly comprises

a drive, which has one or more electrically actuatable actuators, which are configured to change their length in a direction of a longitudinal axis of the valve assembly when a control voltage is applied to the one or more electrically actuatable actuators;

a valve, which comprises a valve member and a valve piston configured to move back and forth along the longitudinal axis by the drive; and

a flexible separator element, which delimits a working space of the valve from the drive and hermetically separates the drive from the medium flowing through the valve or present in the working space,

wherein the piston plate of the valve piston is disposed in a housing shoulder extending in a direction of a drive housing and which is connected to the working space with its open end,

when the valve is opened the piston plate moves away from the working space in a direction of a shoulder plate,

a first spring is disposed between the shoulder plate and the piston plate, and

the first spring presses the valve member against a valve seat when a voltage is not applied to the one or more electrically actuatable actuators.