Compact dosing device for an injector with two fuel circuits for an aircraft turbomachine

Patent metadata

Field	Value
Publication number	US-2016017808-A1
Application number	US-201414772924-A
Country	US
Kind code	A1
Filing date	Mar 5, 2014
Priority date	Mar 5, 2013
Publication date	Jan 21, 2016
Grant date	—

Abstract

A fuel dosing device for a fuel injector of an aircraft turbomachine, including an opening, a movable member for sealing the opening, and elastic return, with the member able to be displaced under the effect of the fuel pressure. The device includes a first outlet communicating with a primary circuit of the injector as well as a second outlet communicating with a secondary circuit. In addition, it is designed such that up to a defined level of displacement of the sealing member, the latter allows the fuel coming from the opening to reach the first outlet and, only beyond the defined level of displacement, the member allows the fuel coming from the opening to reach the second outlet.

First claim

1 - 9 . (canceled)

10 . A fuel metering device for a fuel injector of an aircraft turbomachine, the device comprising an opening for the fuel intake, a movable sealing member for sealing the opening, as well as elastic return means configured to urge the movable sealing member in the direction of a closed position in which the member seals off said opening, the movable sealing member being configured to be displaced from its closed position under the effect of the fuel pressure that is applied on this member,
wherein said metering device comprises a first outlet intended to communicate with a primary circuit of the injector as well as a second outlet intended to communicate with a secondary circuit of the injector, wherein the metering device is configured in such a way that up to a defined level of displacement of the movable sealing member in the direction of a maximum open position, the sealing member allows the fuel coming from said opening to reach said first outlet, and wherein the movable sealing member allows the fuel coming from said opening to reach said second outlet, only beyond said defined level of displacement of the movable sealing member, wherein the metering device comprises: a hollow outer body; a hollow intermediate body housed in the outer body, said opening being made in said intermediate body provided with a seat for receiving the sealing member; said movable sealing member housed slidably movable in said intermediate body; a fuel flow space provided between the intermediate and outer bodies, the intermediate body being provided with orifices for the fuel to pass from the inside of this intermediate body to said fuel flow space, said flow space communicating with said first outlet; a secondary opening for the fuel to pass, provided on the intermediate body, the secondary opening being configured to be sealed by the movable sealing member provided the sealing member has not reached said defined level of displacement, and configured to be released when the movable sealing member is between the defined level of displacement and its maximum opening position, said secondary opening communicating with said second outlet.

11 . The device according to claim 10 , wherein beyond said defined level of displacement of the movable sealing member, the movable sealing member allows the fuel coming from said opening to reach said second outlet and said first outlet.

12 . The device according to claim 10 , wherein said elastic return means comprise at least one first spring and a second spring, with said second spring being arranged in such a way as to not be solicited by the movable sealing member over at least a portion of the travel of the movable sealing member from its closed position, and wherein said first and second springs are arranged in such a way as to each be solicited by the movable sealing member when the movable sealing member is at said defined level of displacement.

13 . The device according to claim 12 , wherein said first and second springs are arranged in parallel.

14 . The device according to claim 12 , wherein said second spring is provided between a stop of the intermediate body and a support part, and wherein the movable sealing member has an additional support part configured to contact said support part only starting from and beyond said defined level of displacement, in the direction of its maximum open position.

15 . The device according to claim 12 , wherein said second spring is provided between a fixed stop of the device and a support part of the movable sealing member, and wherein the movable sealing member has an engaging element configured to engage the support part only starting from and beyond said defined level of displacement in the direction of the maximum open position of the movable sealing member.

16 . The device according to claim 10 , wherein the movable sealing member defines a cavity inside of which the fuel is intended to transit in order to reach said second outlet.

17 . A fuel injector for aircraft turbomachine comprising at least a fuel metering device for a fuel injector of an aircraft turbomachine,
wherein the device comprises an opening for the fuel intake, a movable sealing member for sealing the opening, as well as elastic return means configured to urge the movable sealing member in the direction of a closed position in which the member seals off said opening, the movable sealing member being configured to be displaced from its closed position under the effect of the fuel pressure that is applied on this member, wherein said metering device comprises a first outlet intended to communicate with a primary circuit of the injector as well as a second outlet intended to communicate with a secondary circuit of the injector, wherein the metering device is configured in such a way that up to a defined level of displacement of the movable sealing member in the direction of a maximum open position, the sealing member allows the fuel coming from said opening to reach said first outlet, and wherein the movable sealing member allows the fuel coming from said opening to reach said second outlet, only beyond said defined level of displacement of the movable sealing member, wherein the metering device comprises: a hollow outer body; a hollow intermediate body housed in the outer body, said opening being made in said intermediate body provided with a seat for receiving the sealing member; said movable sealing member housed slidably movable in said intermediate body; a fuel flow space provided between the intermediate and outer bodies, the intermediate body being provided with orifices for the fuel to pass from the inside of this intermediate body to said fuel flow space, said flow space communicating with said first outlet; a secondary opening for the fuel to pass, provided on the intermediate body, the secondary opening being configured to be sealed by the movable sealing member provided the sealing member has not reached said defined level of displacement, and configured to be released when the movable sealing member is between the defined level of displacement and its maximum opening position, said secondary opening communicating with said second outlet, said first outlet communicating with a primary circuit of the injector, and the second outlet communicating with a secondary circuit of this injector.

18 . An aircraft turbomachine combustion chamber comprising a plurality of fuel injectors according to claim 17 .

19 . An aircraft turbomachine comprising a combustion chamber according to claim 18 .

Assignees

• Snecma

Inventors

• Chabaille Christophe
• Loval Sebastien

Classifications

• F23N2235/24

  Valve details · CPC title

• F23N2235/16

  variable flow or proportional valves · CPC title

• F02C7/232 Primary

  Fuel valves {(control of fuel supply by means of fuel metering valves F02C9/263)}; Draining valves or systems (valves in general F16K) · CPC title

• F23R3/36

  Supply of different fuels · CPC title

• F16K11/0716

  with fluid passages through the valve member (F16K11/0704, F16K11/0708, F16K11/0712 take precedence) · CPC title