Patent Publication Number: US-2022220863-A1

Title: Porous regulator with integrated ventilation

Description:
TECHNICAL FIELD OF THE INVENTION 
     The invention relates to a regulator. In particular, the invention relates to a regulator for treating hot air carrying pneumatic power, for example to trigger a pneumatic actuator. Such a regulator can be used in an aircraft, in particular to regulate the air supplied to the pneumatic actuator of a valve of the aircraft, in particular a valve of an air bleed or air conditioning system. 
     TECHNICAL BACKGROUND 
     The regulator allows the treatment of hot air carrying pneumatic power by various treatment elements. Such a regulator can also be known as “servo control.” 
     When the regulator is used in a severe thermal environment such as an aircraft, it is subjected to strong thermal stresses which require special treatment. In particular, regulators comprise elements which are particularly temperature sensitive, such as solenoids for managing the air flow leaving the regulator, pressure regulating membranes, etc. More generally, the term “temperature-sensitive elements” is understood to mean elements which can in particular be deteriorated at high temperatures, or which have reduced performance at high temperatures. 
     Current solutions to protect these sensitive elements are for example:
         Offsetting sensitive elements in a protected region: this solution nevertheless requires the addition of pipes to communicate pressure information, which has a significant impact on the cost and complicates installation;   Adding ventilation to the region, either comprehensively over the entire region, or directed towards sensitive elements: this solution has limited effectiveness on sensitive elements because it is not sufficiently specific to these elements.       

     The inventors have sought a solution to avoid offsetting sensitive elements and to improve ventilation of sensitive elements of the regulator. 
     AIMS OF THE INVENTION 
     The invention thus aims to provide a regulator benefiting from improved cooling. 
     The invention aims in particular to provide a regulator that allows a valve to be regulated, thus making it possible to form a compact valve without having to offset temperature-sensitive elements in protected regions. 
     The invention also aims to provide a regulator particularly suitable for use in an aircraft. 
     DISCLOSURE OF THE INVENTION 
     To this end, the invention relates to a regulator, configured to receive a hot air flow carrying pneumatic power via an air inlet, to treat this hot air and to transmit the treated hot air to an air outlet configured to supply a pneumatic actuator, comprising at least one temperature-sensitive electrical or mechanical element and a regulator body, characterized in that the regulator body is composed of a heat-conducting hollow enclosure forming a cavity at least partially surrounding a duct for transporting the hot air flow, said cavity comprising a cooling air inlet and being at least partially filled with a structural reinforcing metal mesh that allows the cooling air to circulate from the cooling air inlet to a cooling air outlet, and in that the temperature-sensitive electrical and/or mechanical element is arranged in the cavity or in contact with the hollow enclosure of the regulator body so as to be cooled by the cooling air by thermal conduction. 
     A regulator according to the invention thus allows the hot air circulating in at least one of the channels thereof to be cooled in order to reduce the risks of physical degradation or degradation of the performance of temperature-sensitive elements of the regulator. 
     The regulator body supports the elements of the regulator, thus providing part of its structural strength. The regulator body is generally solid in the prior art. Using a metal mesh inside the regulator body helps maintain the structural strength of the body while allowing the passage of cooling air therein. The cooling air provides convection cooling. 
     The metal mesh can occupy all or part of the space formed by the cavity. Parts requiring structural strength can be reinforced by adding the metal mesh; other less critical parts can be left empty so that cooling air can circulate; and other very critical parts can remain solid as long as cooling air can flow through the regulator body. 
     Advantageously and according to the invention, the metal mesh is produced by additive manufacturing. 
     Additive manufacturing of the metal mesh makes it possible to form a metal mesh of the desired design, making it possible to best meet structural constraints as well as constraints in terms of passage of the cooling air. 
     Advantageously and according to the invention, the cooling air outlet is arranged on the regulator body opposite the cooling air inlet, so that the cooling air passes through the cavity of the regulator body. 
     According to this variant of the invention, the cooling air passes through a large 20 volume of the cavity of the regulator body so as to maximize the cooling of the channels and of the temperature-sensitive electrical or mechanical element(s), by being in contact with a larger part of the heat-conducting hollow enclosure. 
     Advantageously and according to the invention, each temperature-sensitive mechanical and/or electrical element is selected from the following list of elements:—a membrane,
         a membrane of a hot air expansion device carrying pneumatic power,   a solenoid,   a torque motor.       

     The membrane is for example a valve membrane or a membrane of an expansion device and allows, for example, the pressure of the hot air flow to be compared with a reference pressure. More generally, the membrane can be any membrane that allows two pressures exerted on either side thereof to be compared. 
     The solenoid allows in particular the air flow leaving the regulator to be managed, by opening or closing a valve allowing the quantity of air necessary for the activation of the pneumatic actuator to be released at the desired time. 
     Other electromechanical, electrical or electronic components can also form the temperature-sensitive elements. 
     Advantageously and according to the invention, the cooling air is flow air drawn from a turbomachine. 
     According to this aspect of the invention, the flow air of the turbomachine (also called fan air) forms particularly advantageous cooling air in an aircraft because it is the source of air among the coldest available in the aircraft. 
     The flow air is air set in motion by the turbomachine. When the turbomachine is a turbojet, the flow air used and the flow air forming the secondary flow are set in motion by the fan of the turbojet. 
     The flow air is also pressurized at the outlet of the turbomachine, which allows ventilation of the regulator body without requiring any particular device to set the flow air in motion. 
     The invention also relates to a valve actuated by a pneumatic actuator, 25 characterized in that said valve comprises a regulator according to the invention configured to supply said pneumatic actuator. 
     By equipping a valve with a regulator according to the invention, it is possible to form a compact valve in which all the elements of the valve are arranged close to one another, without the need to offset some of the elements of the valve, in particular 
     the temperature-sensitive elements of the regulator. 
     The valve can for example be used in an air bleed or air conditioning system of an aircraft. 
     The invention also relates to an aircraft comprising at least one turbomachine, characterized in that said aircraft comprises a regulator according to the invention, and channels for conducting flow air from the turbomachine to the cooling air inlet of the regulator, the flow air from the turbomachine thus forming the cooling air of the regulator. 
     The invention also relates to a regulator, a valve and an aircraft which are characterized in combination by all or some of the features mentioned above or below. 
    
    
     
       LIST OF FIGURES 
       Further aims, features and advantages of the invention will become apparent upon reading the following description, which is provided solely by way of a non-limiting example, and which refers to the accompanying figures, in which: 
         FIG. 1  is a schematic cross-sectional view of a regulator according to one embodiment of the invention. 
         FIG. 2  is a schematic cross-sectional view of a regulator body according to one embodiment of the invention. 
         FIG. 3  is a simplified schematic view of an air conditioning system according to one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF ONE EMBODIMENT OF THE INVENTION 
     For the sake of illustration and clarity, scales and proportions are not strictly adhered to in the figures. 
     Moreover, identical, similar or analogous elements are denoted using the same reference signs throughout the figures. 
       FIG. 1  schematically illustrates in cross-section a regulator  10  according to one embodiment of the invention. 
     The regulator  10  is configured to receive a hot air flow carrying pneumatic power via an air inlet  12 , to treat this hot air and to transmit the treated hot air to an air outlet  14  configured to supply a pneumatic actuator  16 . 
     The air inlet  12  of the regulator is at a first mechanical interface  18  and the air outlet  14  is at a second mechanical interface  20 . The first and second mechanical interfaces are for example air treatment devices such as an expansion device, a flow control valve, etc. These mechanical interfaces comprise temperature-sensitive mechanical or electrical elements  36  such as a membrane of the expansion device, or a solenoid for activating the valve. 
     Temperature-sensitive mechanical or electrical elements  37  may also be arranged on the regulator body. 
     The hot air flow passing through the first mechanical interface  18  enters a duct  22  via a duct inlet  24  and leaves said duct via a duct outlet  26  to reach the second mechanical interface  20 . 
     According to other embodiments, the regulator can comprise more ducts interconnecting at least three mechanical interfaces. 
     In the prior art, such a duct would be either in the open air or surrounded by a solid regulator body forming a solid enclosure around the duct. 
     In this embodiment of the invention, the regulator comprises a regulator body composed of a hollow enclosure  28  forming a cavity  30  at least partially, in this case entirely, surrounding the duct  22 . 
     The regulator body comprises a cooling air inlet  32  and a cooling air outlet  34  that allows the cooling air to circulate inside the cavity  30 . The cooling air inlet  32  is for example a nipple to which a duct supplying cooling air to the regulator can be connected. The cooling air outlet  34  can for example be connected to the ambient air. 
     The use of a completely hollow cavity would create structural risks for the regulator, the regulator body having a support function in the prior art. Thus, in this embodiment of the invention, the cavity is at least partially, in this case fully, filled with a metal mesh produced by additive manufacturing that allows the cooling air to circulate while guaranteeing its structural resistance. 
     The metal mesh is a good compromise between a solid regulator body which would not allow the passage of cooling air and an empty regulator body which does not guarantee the structural resistance of the regulator body. To allow specific structural reinforcements at critical locations, the regulator  10  may also comprise, in other embodiments, solid parts as long as they do not obstruct the cooling air flow between the cooling air inlet  32  and the cooling air outlet  34 . 
     The circulation of the cooling air through the metal mesh makes it possible to cool the hot air circulating in the duct  22 . 
     In addition, the metal mesh and the hollow enclosure  28  are heat conductors, which makes it possible to cool, by thermal conduction, the temperature-sensitive elements  36 ,  37 , for example located in the mechanical interfaces which are directly or thermally connected to the metal mesh via the duct  22  and/or the hollow enclosure  28 , the duct inlet  24 , the duct outlet  26 , etc. 
       FIG. 2  schematically illustrates in cross-section a regulator body  100  according to a second embodiment of the invention. 
     The regulator body  100  comprises a hollow enclosure forming a cavity surrounding two ducts: a first duct  122   a  and a second duct  122   b.    
     The regulator body comprises parts  140  forming the periphery of the enclosure and which can be used to reinforce the structure at sensitive points. The cavity is formed of hollow parts, in particular a completely hollow recess  142 , as well as of metal mesh  144  and of a transient part  144 ′ filled with metal mesh directly connected to the recess  142  and the metal mesh  144 . 
     The cooling air enters through a cooling air inlet  132  formed by a nipple, enters the recess  142  through an orifice  146 , reaches the transient part  144  and circulates in the metal mesh  144 . Cooling air leaves the regulator body  100  through a cooling air outlet  134 . 
     The regulator body can be shaped to match the mechanical interfaces of the regulator, for example it can comprise a location  148  in which the regulator expansion device can be arranged. 
     The metal mesh is represented in  FIGS. 1 and 2  by a plurality of circles joined together for illustrative purposes, but can take different forms. 
       FIG. 3  schematically and in a simplified manner represents an air conditioning system according to one embodiment of the invention, installed in an aircraft and comprising a regulator according to one of the embodiments described above. 
     The aircraft comprises a turbomachine, in particular a turbojet  200 , shown in a simplified manner, comprising a fan  202  allowing the formation of two air flows: a primary air flow  204  intended to be compressed and then injected into a combustion chamber  206 , and a secondary air flow  208  circulating around the part of the turbojet  200  treating the primary air flow  204 . 
     This secondary air flow, which is cold because it comes from the outside air entering the turbojet and has a dynamic pressure generated by the fan  202 , forms flow air, also called fan air because it is set in motion by the fan, which is drawn via a duct  210  leading to the regulator  10 . The flow air thus drawn can be led to the cooling air inlet, making it possible to cool and ventilate the cavity of the regulator body and thus the temperature-sensitive elements, such as the membrane of the expansion device, the solenoid and/or any electrical or mechanical element sensitive to the desired temperature. 
     The regulator  10  is advantageously integrated into an air treatment system  212  intended, for example, to condition the air in the cabin  214  of the aircraft. The regulator 
       10  can, for example, control a pneumatic actuator making it possible to ensure pressure regulation.