Pneumatic valve

1. A pneumatic valve, comprising:

an air chamber having a supply connector for supplying compressed air to the air chamber;

one or more discharge connectors for discharging compressed air from the air chamber;

there being provided in the pneumatic valve an actuator with a unitary closure element which, i) when the actuator is activated, is arranged in a blocking position in which the supply of compressed air via the supply connector is blocked by the unitary closure element, and ii) when the actuator is deactivated, is arranged in a free position in which the supply of compressed air via the supply connector is not blocked by the unitary closure element; and

a check valve with an elastic means arranged at the supply connector, the check valve comprising a separate closure component which is different from the unitary closure element and on which an elastic force of the elastic means acts;

wherein the elastic force of the elastic means in the free position of the unitary closure element acts on the separate closure component of the check valve to cause the separate closure component to block back-flow of compressed air from the air chamber into the supply connector when there is no supply of compressed air at the supply connector, and

wherein on deactivation of the actuator, a restoring force of the elastic means moves the unitary closure element into the free position.

2. The pneumatic valve as claimed in claim 1 , wherein the pneumatic valve comprises a first and a second discharge connector, wherein, in the free position of the unitary closure element when there is a supply of compressed air, the compressed air is allowed to flow through from the supply connector to the first discharge connector, and at the same time the second discharge connector is blocked, and wherein, in the blocking position of the unitary closure element, a connection is established between the first discharge connector and the second discharge connector via the air chamber.

3. The pneumatic valve as claimed in claim 1 , wherein the elastic means is a spring.

4. The pneumatic valve as claimed in claim 3 , wherein the spring is a helical spring.

5. The pneumatic valve as claimed in claim 1 , wherein at least one part of the elastic means is guided in at least one bore in the unitary closure element.

6. The pneumatic valve as claimed in claim 1 , wherein the pneumatic valve is a solenoid valve with an electromagnetic actuator, in which the unitary closure element in the form of an armature can be moved by energizing a coil.

7. The pneumatic valve as claimed in claim 1 , wherein a single sealing seat is provided at the supply connector, wherein in the blocking position the unitary closure element exerts, via the elastic means, a force on the separate closure component in order to thus press the separate closure component onto the single sealing seat and block the supply connector, and wherein in the free position the separate closure component, when there is no supply of compressed air at the supply connector, is pressed onto the single sealing seat by the elastic force of the elastic means.

8. The pneumatic valve as claimed in claim 1 , wherein the elastic means is arranged between a first stop on the unitary closure element and a second stop on the separate closure component.

9. The pneumatic valve as claimed in claim 1 , wherein the separate closure component is spherical or conical at an end facing the supply connector.

10. The pneumatic valve as claimed in claim 1 , wherein the separate closure component has a continuation which extends away from the supply connector and against which the unitary closure element presses in the blocking position in order to block the supply of compressed air via the supply connector.

11. The pneumatic valve as claimed in claim 10 , wherein the continuation is guided at least in part in a bore of the unitary closure element or the continuation extends at least in part through the elastic means.

12. A device for the pneumatic adjustment of a seat, comprising multiple air bladders the filling and emptying of which adjusts the seat, wherein each air bladder is assigned a separately switchable pneumatic valve as claimed in claim 1 , wherein all of the pneumatic valves are connected via their respective supply connector to a common compressed air supply, and each air bladder is connected to a discharge connector of its associated pneumatic valve.

13. The device as claimed in claim 12 , wherein each air bladder is assigned a pneumatic valve comprising a first and a second discharge connector, wherein, in the free position of the unitary closure element when there is a supply of compressed air, the compressed air is allowed to flow through from the supply connector to the first discharge connector, and at the same time the second discharge connector is blocked, and wherein, in the blocking position of the unitary closure element, a connection is established between the first discharge connector and the second discharge connector via the air chamber, wherein the first discharge connector is a working connector to which a respective air bladder is connected for filling with compressed air from the compressed air supply, and wherein the second discharge connector is a venting connector for venting the respective air bladder.

14. The device as claimed in claim 13 , wherein the actuator of each pneumatic valve is configured such that, in the blocking position of the unitary closure element, the actuator exerts on a feed air connector a pressure which is elevated, by the maximum permissible filling pressure of the air bladders, in comparison to the pressure on the feed air connector which the check valve exerts on the supply connector in the free position of the unitary closure element when there is no supply of compressed air at the supply connector.

15. A pneumatic valve, comprising:

an air chamber having a supply connector for supplying compressed air to the air chamber;

one or more discharge connectors for discharging compressed air from the air chamber;

there being provided in the pneumatic valve an actuator with a closure element which, i) when the actuator is activated, is arranged in a blocking position in which the supply of compressed air via the supply connector is blocked, and ii) when the actuator is deactivated, is arranged in a free position in which the supply of compressed air via the supply connector is permitted; and

a check valve with an elastic means arranged at the supply connector;

wherein the actuator is configured such that the closure element, on deactivation of the actuator, is moved by a restoring force into the free position,

wherein an elastic force of the elastic means in the free position of the closure element prevents back-flow of compressed air from the air chamber into the supply connector when there is no supply of compressed air at the supply connector,

wherein the restoring force for moving the closure element into the free position is generated by the elastic means of the check valve,

wherein the check valve comprises a separate closure component which is different from the closure element and on which the elastic force of the elastic means acts in order, in the free position of the closure element, to prevent a back-flow of compressed air from the air chamber into the supply connector when there is no supply of compressed air at the supply connector, and

wherein two separate sealing seats for the closure element and the check valve are provided at the supply connector, wherein in the blocking position a sealing face of the closure element is pressed onto the sealing seat for the closure element, and wherein in the free position the separate closure component, when there is no supply of compressed air at the supply connector, is pressed onto the sealing seat for the check valve by the elastic force of the elastic means.