Device for supplying hydraulic fluid to a ram and mechanism for controlling the pitch of the blades of a turbine engine propeller comprising the ram

Patent metadata

Field	Value
Publication number	US-2016207609-A1
Application number	US-201415023479-A
Country	US
Kind code	A1
Filing date	Sep 22, 2014
Priority date	Sep 24, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A hydraulic ram comprising a fixed support, a cylinder that is movable in translation relative to the support, a piston secured inside the cylinder delimiting two chambers with the cylinder and a device for supplying the chambers with hydraulic fluid upstream from the fixed support. The ram is characterised by the fact that the supply device comprises telescopic channels, each telescopic channel comprising two tubular elements sliding one into the other, a first tubular element being rigidly connected to the fixed support at one end and the second tubular element being rigidly connected to the cylinder at at least two points separated from each other along a generatrix of the cylinder. The invention is applicable to controlling the pitch of the blades of a turbine engine propeller.

First claim

1 . Hydraulic actuator comprising a support, a cylinder which is translatably movable relative to the support, a piston which is rigidly connected to the support inside the cylinder and delimits two chambers with the cylinder, and a device for supplying the chambers with hydraulic fluid upstream from the support, wherein the supply device comprises telescopic pipes each telescopic pipe comprising two tubular elements which slide one inside the other, a first tubular element being rigidly connected to the support at one end and the second tubular element being rigidly connected to the cylinder at at least two points which are remote from one another along a generatrix of the cylinder, one of said chambers being supplied with fluid via a first telescopic pipe on one portion of the travel of the cylinder and via a second telescopic pipe on the remaining portion of the travel of the cylinder.

2 . Hydraulic actuator according to claim 1 , wherein the first pipe comprises a first closure means which is arranged so as to close the pipe at the end of said travel portion and the second pipe comprises a second closure means which is arranged so as to keep the second pipe closed on said travel portion of the cylinder and open on said remaining travel portion of the cylinder.

3 . Actuator according to claim 2 , wherein the closure means of the first or the second pipe is formed by the first tubular element and the second tubular element of said pipe interacting, the second tubular element having a passage connecting the first tubular element to said chamber, and the first tubular element having openings which are uncovered by said passage.

4 . Actuator according to claim 3 , wherein the first tubular element is closed at its end opposite the collar and has said openings on the side, the second tubular element has a portion having such a diameter that said lateral openings are closed and a portion having a wider diameter so as to form said passage.

5 . Hydraulic actuator according to claim 1 , wherein the second pipe is connected to said chamber by a pipe which is arranged in parallel with the second pipe.

6 . Actuator according to claim 1 , wherein the first tubular elements of the pipes are connected to the support by a swan-neck-shaped portion.

7 . Mechanism for controlling the pitch of a variable-pitch propeller, comprising an actuator according to claim 1 , the actuator being rigidly connected to the stator portion of the propeller.

8 . Mechanism according to claim 7 , wherein the first pipe is a low-pitch pipe, and supplies said chamber with fluid over a pitch-setting range, and the second pipe is a pitch-inversion pipe, supplying said chamber with fluid over a thrust-inversion range of the propeller.

9 . Mechanism according to claim 7 , wherein the other chamber is supplied with fluid via a third telescopic pipe, which is a high-pitch pipe, having a first tubular element and which is rigidly connected to the stationary support and a second tubular element which communicates with said other chamber.

Assignees

• Snecma

Inventors

• Belmonte Olivier
• Curlier Augustin

Classifications

• F15B15/149

  Fluid interconnections, e.g. fluid connectors, passages · CPC title

• B64C11/38 Primary

  fluid, e.g. hydraulic · CPC title

• F15B15/14

  of the straight-cylinder type · CPC title

• B64C11/48

  Units of two or more coaxial propellers · CPC title

• B64D2027/005

  Aircraft with an unducted turbofan comprising contra-rotating rotors, e.g. contra-rotating open rotors [CROR] · CPC title