The present invention relates to fluid distribution and control valves, in particular for an onboard system for delivering respiratory gas to a passenger.
Pilots of modern aircraft, in particular of fighter planes, are supplied with respiratory gas by systems which deliver pure oxygen or an oxygen-enriched mixture.
A control valve of the proportional type with one inlet and two outlets for an onboard system for delivering respiratory gas is described in EP-A-0 499 505 (Zapata et al.).
In current practice, an emergency oxygen source is provided as standard in order to deal with possible failure of the main oxygen source, and a selector element, activated automatically or manually, allows the user to switch the inlet of the control valve to the main source or, if this fails, to the emergency source.
The object of the present invention is to propose a novel architecture of a fluid distribution and control valve combining the function of selection between two sources of fluid and the function of conventional control, using a single mobile structure of greatly simplified and compact arrangement and of increased reliability.
To do this, according to one characteristic of the invention the fluid distribution and control valve comprises a valve body defining four internal zones which are each connectable to an external fluid circuit, and a mobile structure which can be moved into at least four positions in order to selectively establish a fluid communication between two of these zones and to isolate each of the two other zones, a first of these zones being connectable to a user fluid circuit and being able to be selectively brought into communication with each of the three other zones depending on the movement of the mobile structure.
According to other characteristics of the invention, the valve comprises:
The present invention also relates to an onboard system for delivering respiratory gas to a passenger, said system comprising such a valve, and the sources of pressurized fluid typically being a main oxygen source and an emergency oxygen source.
Other characteristics and advantages of the present invention will become clear from the following description of an embodiment given by way of example and not intended to be limiting. In the description, reference is made to the attached drawings, in which:
In the embodiment shown schematically in the figures, a fluid distribution and control valve according to the invention comprises a valve body 1, whose general configuration is advantageously cylindrical, and in which are formed a multiplicity of zones separated from one another by partition walls provided with through-orifices which can be selectively closed or opened by means of a valve slide designated generally by reference number 2.
More specifically, as is shown in
The zones 3 and 5 are separated, by partition walls 7 and 8, respectively, from a first intermediate chamber 9 and from a second intermediate chamber 10 which are themselves separated, respectively, by partition walls 11 and 12, from a second zone 13 provided with a fluid inlet/outlet passage 14, and from a third zone 15 provided with a fluid inlet/outlet passage 16.
The partition walls 7, 8, 11, 12 are mutually parallel and in each case comprise a through-opening such as those identified as 17, 18 and 19 in the figures, which through-openings are formed in alignment with one another and in which there slides the slide 2 of cylindrical shape provided locally with a thinner zone (20), advantageously of varying profile, making it possible, depending on the position of the slide, to allow fluid to pass through one of the openings, such as 17 to 19, and to control the flow of fluid thus passing from a zone to a chamber, and vice versa, in the body of the valve.
As can be seen from the figures, in the configuration according to
In the embodiment shown, the first zone 3 is in permanent communication with the intermediate chambers 9 and 10 via openings 21 and 22 formed, respectively, in the partition walls 7 and 8.
The slide 2 can be continuously positioned, between the end position in
The function of the valve in its application to an onboard system for delivery of oxygen to an aircraft pilot will now be described.
In such a system, the first zone 3 is connected via the passage 4 to a user circuit U supplying the pilot's mask M. The second zone 13 is connected via the passage 14 to a main source S1 of oxygen, for example an oxygen generator of the adsorption or permeation type, and the fluid passage 16 of the third zone 15 is connected to an emergency source S2 of gaseous or liquid oxygen. The fluid passage 6 of the fourth zone 5 is connected to a vent circuit 25 opening to outside the cockpit.
Although the present invention has been described with reference to a specific embodiment, it is not limited to the latter and is instead open to modifications and variations which will be obvious to the skilled person from the scope of the claims attached. In particular, the particular structure of the slide 2 and of the cooperating openings such as 17, 18 and 19 can be adapted with varying profiles, and the slide can be replaced by a rotary valve element opening into zones which are spaced angularly apart in the valve body and are separated by radial partition walls.
Number | Date | Country | Kind |
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02/12239 | Oct 2002 | FR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/FR03/50066 | 9/25/2003 | WO | 10/31/2005 |