Pneumatic circuit for supplying air to at least one discharge valve and to at least one device for depressurizing an oil enclosure in a turbine engine

Patent metadata

Field	Value
Publication number	US-10890930-B2
Application number	US-201816217675-A
Country	US
Kind code	B2
Filing date	Dec 12, 2018
Priority date	Dec 19, 2017
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

The invention provides a pneumatic circuit for supplying air to at least one discharge valve that is pneumatically actuated and to at least one depressurizing device for depressurizing an oil enclosure in a turbine engine, the pneumatic circuit comprising: a pneumatic control unit having at least one solenoid valve supplying compressed air to a discharge valve of a compressor of the turbine engine; at least one depressurizing device for depressurizing an oil enclosure of the turbine engine, the device including a compressed air ejector for depressurizing the oil enclosure; and a pneumatic bistable member that is supplied with air by different first and second compressed air sources and that is suitable for supplying the pneumatic control unit and the depressurizing device with air coming from the first or the second compressed air source as a function of the operating speed of the turbine engine.

First claim

The invention claimed is:

1. A pneumatic circuit for supplying air to at least one discharge valve that is pneumatically actuated and to at least one depressurizing device for depressurizing an oil enclosure in a turbine engine, the pneumatic circuit comprising:
a pneumatic control unit having at least one solenoid valve supplying compressed air to a discharge valve of a compressor of the turbine engine; and
at least one depressurizing device for depressurizing an oil enclosure of the turbine engine, the device including
a compressed air ejector for depressurizing the oil enclosure; wherein
the pneumatic circuit further comprises a pneumatic bistable member that is supplied with compressed air by different first and second compressed air sources and that is suitable for supplying the pneumatic control unit and the depressurizing device with the compressed air coming from the first or the second compressed air source as a function of an operating speed of the turbine engine.

2. The circuit according to claim 1 , wherein the pneumatic bistable member comprises an actuator for supplying the pneumatic control unit and the depressurizing device with the compressed air coming from the first or the second compressed air source depending on the operating speed of the turbine engine, and a selector for selecting the source of the compressed air supplied by the actuator as a function of a pressure level of the first compressed air source.

3. The circuit according to claim 2 , wherein:
the selector of the pneumatic bistable member comprises:
a selector piston separating two selector chambers in leaktight manner, one of the selector chambers being supplied with ambient air at ambient pressure and the other selector chamber being supplied with the compressed air coming from the first compressed air source, which air is at a pressure higher than the ambient pressure at all operating speeds of the turbine engine; and
the actuator of the pneumatic bistable member comprises:
an actuator piston that separates two actuator chambers in leaktight manner, one of the actuator chambers being supplied with the ambient air at ambient pressure coming from the selector, and the other actuator chamber being supplied with the compressed air coming from the second compressed air source; and
a valve member having two seats and secured to the actuator piston, thereby forming a two-way selector valve for causing an outlet of the actuator to communicate selectively either with the actuator chamber supplied with the compressed air coming from the second compressed air source, or else with an inlet connected to the first compressed air source.

4. The circuit according to claim 3 , wherein the selector piston of the selector of the pneumatic bistable member includes a return spring that is rated by a predetermined pressure defining a changeover threshold for the pneumatic bistable member.

5. The circuit according to claim 4 , wherein the pressure defining the changeover threshold of the pneumatic bistable member is predetermined to enable the pneumatic bistable member to supply the pneumatic control unit and the depressurizing device with compressed air coming from the first compressed air source at low speeds of operation of the turbine engine and coming from the second compressed air source at high speeds of operation of the turbine engine.

6. The circuit according to claim 5 , wherein the first compressed air source is a high-pressure stage of a high-pressure compressor of the turbine engine and the second compressed air source is an intermediate stage of the high-pressure compressor.

7. The circuit according to claim 1 , wherein the pneumatic circuit does not include an air/air heat exchanger upstream from the pneumatic control unit.

8. The circuit according to claim 1 , wherein the depressurizing device does not include an internal flow rate selection valve for upstream from the ejector.

9. A turbine engine including a pneumatic circuit according to claim 1 .

Assignees

• Safran Aircraft Engines

Inventors

• Angevin Thomas Roger Jacques

Classifications

• F02C9/18 Primary

  by bleeding, bypassing or acting on variable working fluid interconnections between turbines or compressors or their stages {(F02C3/113 takes precedence)} · CPC title

• F01D25/183

  Sealing means · CPC title

• F05D2260/601

  using an ejector or a jet pump · CPC title

• F05D2270/65

  Pneumatic actuators · CPC title

• F02C7/06

  Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) · CPC title