DEVICE FOR MEASURING THE PRESSURE AND TEMPERATURE OF A FLUID

Abstract

The invention relates to a device (20) for measuring the pressure and temperature of a fluid, comprising: - a single-piece measuring assembly (20') comprising: - a support (24) comprising: a flat plate (39), and a conduit (40) centered on the longitudinal axis (X) and extending longitudinally from the plate (39) to the outside of the retaining body (23), the conduit (40) having at least one opening (44) opposite the plate (39) for the passage of the fluid (F) into the conduit (40), - a pressure sensor (46) arranged in the annular housing (37) of the retaining body (23), and - a temperature sensor (47) comprising at least one electrical conductor (45) extending along the conduit (40), the electrical conductor (45) being integrated into the support (24), which is formed in one piece with the electrical conductor (45). (Shorthand figure: Figure 3)

Description

Title of the invention: DEVICE FOR MEASURING THE PRESSURE AND TEMPERATURE OF A FLUID Technical field of the invention

[0001] The invention relates to the field of devices for measuring the pressure and temperature of a fluid, in particular for motor vehicles.

[0002] The invention relates in particular to the field of pressure and temperature measuring devices comprising a pressure sensor and a temperature sensor. Technical background

[0003] Motor vehicles are equipped with an air conditioning system comprising a refrigerant circuit. In some motor vehicles, particularly electric vehicles, the air conditioning system is also implemented as a heat pump or for the thermal management of various components of the motor vehicle, such as the electric battery, the electric motor or the power system.

[0004] Typically, the refrigeration circuit includes pipes for circulating a refrigerant fluid from one component to another. During the overall thermal management of the vehicle, the temperature and pressure of the refrigeration circuit can vary, and it is necessary to control these parameters to ensure optimal thermal management of the vehicle.

[0005] In order to control the temperature and pressure of this fluid, it has been proposed to equip the refrigeration circuits with a device for measuring the pressure and temperature of the fluid.

[0006] A pressure and temperature measuring device typically has a longitudinal axis and extends longitudinally between a first end and a second opposite end which is connected to one of the pipes of the refrigerant circuit.

[0007] The pressure and temperature measuring device further includes a temperature sensor which includes a fluid temperature-sensitive element and a pressure sensor which includes a fluid pressure-sensitive element.

[0008] Furthermore, in order to limit leaks and allow for accurate measurement of the various parameters, the pressure and temperature measuring device must be sealed. To achieve this seal, it has been proposed to arrange a sealing gasket and an adhesive layer between the measuring device and the pipe. Several sealing gaskets or adhesive layers are also added to the measuring device to reinforce its seal.

[0009] The pressure and temperature measuring device further includes electrical connections enabling the conditioning and transmission of the signals of the measured quantities.

[0010] Although it allows for the measurement of both fluid pressure and temperature through a single measuring device, this device is not entirely satisfactory. Indeed, the temperature must be measured directly in the pipe, which presents a challenge with regard to the sealing of the temperature sensor.

[0011] Furthermore, the sealing solutions of the measuring device are not optimal. The combination of the sealing gasket and adhesive layers for each sensor complicates the assembly of the pressure and temperature measuring device. Also, the increased number of sealing gaskets and adhesive layers increases the device's overall size.

[0012] Therefore, there is a need to provide a device for measuring the pressure and temperature of a fluid, which is robust, accurate and leak-proof while being simple and compact. Summary of the invention

[0013] To this end, the invention proposes a device for measuring the pressure and temperature of a fluid, the measuring device having a longitudinal axis.

[0014] The measuring device is remarkable in that it comprises:

[0015] - an annular retaining body extending around the longitudinal axis and comprising an annular housing and a central passage centered on the longitudinal axis,

[0016] - a single-piece measuring assembly comprising:

[0017] - a support comprising:

[0018] a flat plate disposed in the annular housing of the retaining body, the plate having a central orifice centered on the longitudinal axis for the passage of the fluid, and

[0019] a conduit centered on the longitudinal axis and extending longitudinally from the plate to the outside of the retaining body, the conduit having at least one opening opposite the plate for the passage of the fluid into the conduit,

[0020] - a pressure sensor arranged in the annular housing of the retaining body, the pressure sensor including:

[0021] a support layer comprising a first face having a first electrical track and a second opposite face, and

[0022] a deformable membrane disposed between the plate and the support layer,

[0023] - a temperature sensor comprising:

[0024] a thermistor located outside the conduit on the opening side, and

[0025] at least one electrical conductor extending along the conduit and connecting the thermistor to the first electrical track, the electrical conductor being integrated into the support which is formed in one piece with the electrical conductor.

[0026] The pressure and temperature measuring device according to the invention thus comprises a single-piece measuring assembly which includes a support, a pressure sensor and a temperature sensor.

[0027] The pressure and temperature sensors are therefore integrated into the support, thus forming the one-piece measuring assembly.

[0028] Thanks to such a configuration, the pressure and temperature measuring device is sealed and ensures accurate measurement of pressure and temperature parameters.

[0029] The invention may comprise one or more of the following features, taken individually or in combination with each other:

[0030] — the electrical conductor extends into the conduit,

[0031] - the deformable membrane is connected to the plate by an adhesive layer,

[0032] - the adhesive layer includes an annular opening centered on the axis longitudinal,

[0033] - the pressure sensor includes a bonding layer arranged between the layer of support and deformable membrane,

[0034] - the bonding layer and / or the adhesive layer comprises a polymer material chosen from epoxy or silicate,

[0035] - the deformable membrane has first and second opposite faces, the the second side being positioned on the plate and the first side having a third electrical track connected to the first electrical track,

[0036] - the electrical conductor has a first portion embedded in the plate and a first end connected to the first electric track and the first section,

[0037] - the support layer comprises a ceramic material such as a silicon oxide, or glass or a polymeric material,

[0038] - a sleeve connected to one end of the conduit, the thermistor being located in the sleeve,

[0039] - an insert mounted in the retaining body and around the conduit, the insert and the body of retaining wall forming a single unit

[0040] - a first annular seal is mounted between the plate and the insert,

[0041] - a second annular seal is mounted around the insert, outside the retaining body. Brief description of the figures

[0042] Other features and advantages will become apparent from the following description of non-limiting embodiments of the invention with reference to the accompanying drawings in which:

[0043] [Fig. 1] is a schematic longitudinal cross-sectional representation of a fluid circuit comprising a measuring device according to the invention,

[0044] [Fig.2] is a perspective view of the measuring device according to one embodiment of the invention,

[0045] [Fig.3] is a longitudinal cross-sectional view of the measuring device of [Fig.2],

[0046] [Fig. 4] is a top view of the hood that can be fitted to the measuring device the invention,

[0047] [Fig. 5] is a perspective view of the retaining body equipping the measuring device of the invention,

[0048] Figure 6 is a longitudinal cross-sectional view of a portion of the measuring device according to one embodiment of the invention.

[0049] [Fig.7] is a perspective view of the support according to the invention carrying the temperature sensor,

[0050] [Fig. 7a] is a perspective view of the one-piece measuring assembly according to the invention, comprising the support of [Fig. 7] and the pressure and temperature sensors,

[0051] [Fig.8] is a top view of the support of [Fig.7],

[0052] [Fig. 9] is a top view of the retaining body in which the sensitive components of the sensor

[0053] [Fig. 10] is a perspective view of the temperature sensor,

[0054] [Fig. 1 1] is a cross-sectional diagram of the pressure and temperature sensor according to a example of implementation,

[0055] [Fig. 12] is a perspective view of a threaded insert that can be fitted to the measuring device of the invention. Detailed description of the invention

[0056] Fig. 1 illustrates, for example, in a very schematic way, a refrigerant circuit 10 to which the invention can be applied.

[0057] The refrigerant circuit is for example intended for a vehicle 12, in particular an electric motor vehicle, equipped with a heat pump for example.

[0058] The refrigerant circuit 10 includes, for example, a source of refrigerant fluid F.

[0059] The refrigerant circuit 10 further comprises at least one pipe 14 for the Fluid passage F. Pipeline 14 extends along a longitudinal axis Y. It comprises a polymeric or metallic material. Pipeline 14 includes an internal passage 16 for the circulation of fluid F. Pipeline 14 is, for example, formed from a plurality of interconnected conduits or from a single section.

[0060] The pipeline 14 further includes a measuring port 18 which opens into the internal passage 16. The measuring port 18 has an axis for example perpendicular to the longitudinal axis Y of the pipeline 14.

[0061] The fluid F is, for example, a liquid, such as a coolant, an oil, water, or a gas, such as a refrigerant gas. The fluid has a temperature, for example, between -40°C and 150°C and a relative pressure, for example, between 0 bar and 120 bar, preferably between 0 bar and 35 bar.

[0062] The refrigerant circuit 10 further includes a measuring device 20 for the pressure and temperature of the fluid F. The measuring device 20 is arranged in the measuring port 18. The measuring device 20 is connected to the pipe 14. It is connected to the pipe 14 by welding, brazing, or mechanical connection. Welding can be carried out by vibration, rotation, or laser when the pipe 14 comprises a polymer material, or, for example, by brazing when the pipe 14 comprises a metallic material. The mechanical connection can be made by screwing or clipping.

[0063] The measuring device 20 extends into the internal passage 16.

[0064] With reference to [Fig.2], the measuring device 20 has a longitudinal axis X. The longitudinal axis X extends, for example, perpendicularly to the longitudinal axis Y of the pipeline 14. The longitudinal axis X also extends parallel to the axis of the measuring port 18.

[0065] In the following description, the terms "longitudinal", "longitudinally", "radially", "radially", are understood with respect to the longitudinal axis X of the measuring device 20.

[0066] The terms "exterior", "externally", "external", "interior", "internally", "internal", are understood relative to the distance of the longitudinal axis X along a radial axis to the longitudinal axis X.

[0067] The measuring device 20 extends longitudinally between a first end 21a and a second opposite end 21b. The second end 21b is located in the internal passage 16.

[0068] With reference to figures 2 and 3, the measuring device 20 advantageously comprises a hood 22, a retaining body 23 advantageously connected to the hood 22 and a monobloc measuring assembly 20' comprising a support 24 carried by the retaining body 23, a pressure sensor 46 and a temperature sensor 47.

[0069] The hood 22 is centered on the longitudinal axis X. Preferably, the hood 22 is monolithic or formed from a single piece of material. It comprises a first part 25 and a second part 26 connected to the first part 25. The first part 25 is substantially tubular and has a substantially rectangular cross-section. The first part 25 is hollow and has an internal housing 25a. The internal housing 25a can receive electrical connections. The second part 26 is annular and centered on the longitudinal axis X. It has an internal annular housing 26a.

[0070] The first and second parts 25, 26 comprise a polymeric material. The first and second parts 25, 26 are preferably transparent at a given wavelength. The wavelength is, for example, between 500 nm and 2000 nm. This characteristic of the hood 22 allows it to be joined, for example, by laser welding to the retaining body 23.

[0071] The hood 22 further comprises connecting arms 27, for example at least two radially opposed connecting arms 27. Each connecting arm 27 extends axially from the second part 26 to the second end 21b of the measuring device 20. Each connecting arm 27 has a slot 27a. The hood 22 may comprise more than two connecting arms 27.

[0072] The hood 22 may further include a transverse wall 28 which separates the internal housings 25a, 26a from the first and second parts 25, 26.

[0073] As more clearly seen in [Fig. 4], the cover 22 further comprises at least one electrically conductive tab 30 and advantageously a plurality of electrically conductive tabs 30. Each electrically conductive tab 30 extends longitudinally into the internal recesses 25a, 26a of the first and second parts 25, 26, passing through the transverse wall 28. The electrically conductive tabs 30 are regularly distributed along the transverse wall 28. Preferably, the cover 22 comprises two, three, or four electrically conductive tabs 30.

[0074] The electrically conductive tabs 30 are for example overmolded with the first and second parts 25, 26 of the hood 22 or are mechanically integrated into these first and second parts 25, 26.

[0075] Each electrically conductive tab 30 preferably comprises an electrically conductive material, in particular a metallic material.

[0076] With reference to [Fig.5], the retaining body 23 is annular and centered on the longitudinal axis X. It includes a central passage 31 centered on the longitudinal axis X. The retaining body 23 further includes a circular portion 32 connected to a polygonal portion 33.

[0077] The circular portion 32 comprises a transverse wall 34 extending around the central passage 31 and an annular longitudinal wall 35 extending longitudinally from the transverse wall 34. The retaining body 23 further comprises internal ribs 36 connecting the transverse wall 34 to the longitudinal wall 35. The internal ribs 36 are regularly distributed in pairs around the longitudinal axis X.

[0078] The retaining body 23 further includes an annular housing 37 delimited by the circular portion 32. In particular, the annular housing 37 is delimited radially by the longitudinal wall 35 and axially by the transverse wall 34.

[0079] The retaining body 23 further comprises fastening tabs 38, preferably two radially opposed fastening tabs 38. The fastening tabs 38 are located on the circular portion 32 outside the annular housing 37.

[0080] The retaining body 23 is located inside the hood 22. In particular, the circular portion 32 is engaged inside the hood 22. For example, the longitudinal wall 35 of the circular portion 32 is located inside the second part 26 of the hood 22.

[0081] The retaining tabs 38 cooperate with the connecting arms 27. In particular, each retaining tab 38 is respectively engaged in the slot 27a of the connecting arms 27. Such cooperation of the cover 22 and the retaining body 23 allows positioning and retention of the retaining body 23 in the cover 22 in order to facilitate welding of the cover 22 around the retaining body 23.

[0082] With reference to Figures 7 and 8, the support 24 of the monobloc measuring assembly 20' comprises a plate 39 and a conduit 40. The plate 39 extends in a plane perpendicular to the longitudinal axis X. It has, for example, a polygonal shape, preferably rectangular or square. The plate 39 thus has four vertices 39a connected by sides 39b.

[0083] The plate 39 includes a central orifice 41 which is centered on the longitudinal axis X. The central orifice 41 has a substantially circular or oblong shape. It is through-hole.

[0084] In addition, the plate 39 may advantageously include a notch 42. The notch 42 is for example formed on one of the vertices 39a of the plate 39. It has a shape for example semi-circular.

[0085] The plate 39 is located in the housing 37 of the retaining body 23. In particular, the plate 39 rests on the transverse wall 34 of the retaining body 23. The plate 39 is positioned in the retaining body 23 by means of the internal ribs 36.

[0086] The conduit 40 extends longitudinally from the plate 39 to the outside of the retaining body 23. The conduit 40 is centered on the longitudinal axis X. The conduit 40 extends from the plate 39 to an end, for example a closed end, located outside the retaining body 23. The conduit 40 has at least one opening 44 located on the side of the closed end and is thus axially opposite to the plate 39. The opening 44 allows the fluid F to enter the conduit 40. The opening 44 is formed on an annular lateral wall of the conduit 40. The opening 44 thus has an axis that extends radially with respect to the longitudinal axis X. The opening 44 may have an elongated shape, for example, a roughly rectangular one. Advantageously, the duct 40 has two radially opposed openings. The duct 40 has a cross-section, for example, circular.

[0087] The conduit 40 has an internal passage communicating with the central orifice 41 of the plate 39. The fluid F can thus flow through the conduit 40 to the plate 39 via the central orifice 4L

[0088] The support 24 comprises, for example, a polymer material.

[0089] The support 24 forms a single unit. Indeed, the plate 39 and the conduit 40 are formed from a single piece.

[0090] As more clearly seen in [Fig.7a], the monobloc measuring assembly 20' further comprises at least one electrical conductor 45, a pressure sensor 46, and a temperature sensor 47.

[0091] Advantageously, the one-piece measuring assembly 20' comprises two electrical conductors 45. Each electrical conductor 45 extends along the conduit 40 and, for example, within the conduit 40, extending beyond the end opposite the plate 39. Each electrical conductor 45 extends longitudinally between first and second ends 45a, 45b located outside the conduit 40. The first end 45a is located opposite the closed end of the conduit 40 on the side of the opening 44. In one embodiment, this first end 45a may have an angled shape. The second end 45b is opposite the plate 39. It is located outside the conduit 40.

[0092] Each electrical conductor 45 can be in several parts or formed in one piece.

[0093] Each electrical conductor 45 comprises an electrically conductive material. The electrically conductive material is, for example, a metal or a metal alloy.

[0094] Each electrical conductor 45 may further include an electrically insulating sheath comprising, for example, a polymer material such as an epoxy resin or a thermoplastic.

[0095] The electrical conductor(s) 45 form a single, monolithic piece with the support 24. Each electrical conductor 45 is integrated into the support 24, which is formed by overmolding. In particular, the support 24 is overmolded with each electrical conductor 45, thus forming a single, monolithic piece. This reduces the number of parts, facilitates assembly, and improves the sealing of the measuring device 20. Sintering can be performed as an alternative to overmolding.

[0096] Thus, each electrical conductor 45 is embedded in the support 24.

[0097] As more clearly seen in [Fig. 10], the temperature sensor 47 comprises a Thermistor 48. Thermistor 48 is, for example, connected to each conductor electrical 45 by electrical wires 49. The electrical wires 49 are for example soldered to the second end 45b of each electrical conductor 45. The thermistor 48 is for example a negative temperature coefficient thermistor, also known by the acronym NTC.

[0098] The pressure sensor 46 is of the capacitive or piezoresistive type. As can be seen more clearly in [Fig. 11], the pressure sensor 46 is of the multilayer type. It comprises a support layer 50, a deformable membrane 51 disposed between the plate 39 and the support layer 50, and advantageously a bonding layer 52 arranged between the support layer 50 and the deformable membrane 51.

[0099] The one-piece measuring assembly 20' is located in the annular housing 37. The support layer 50 has a polygonal shape, for example, square or rectangular. The support layer 50 has a thickness, for example, between 0.5 mm and 2 mm, in particular between 0.9 mm and 1.1 mm. Advantageously, the support layer 50 comprises a ceramic material such as alumina, silicon dioxide, or glass, or a polymeric material. The support layer 50 has first and second faces 50a, 50b that are axially opposed.

[0100] The bonding layer 52 connects the support layer 50 to the deformable membrane 51 while accommodating the differential thermal expansions between the support layer 50 and the deformable membrane 51 in order to improve the accuracy of the pressure measurement. The bonding layer 52 has a polygonal shape, for example, square or rectangular. The bonding layer 52 has a thickness, for example, between 10 µm and 50 µm. The thickness of the bonding layer 52 is less than the thickness of the support layer 50. Advantageously, the bonding layer 52 comprises a polymeric material, such as an epoxy polymer or a silicate.

[0101] The deformable membrane 51 extends over the plate 39 and is bonded to the plate by an adhesive layer 51'. The deformable membrane 51 has a polygonal shape, for example, square or rectangular. The deformable membrane 51 has a thickness, for example, between 0.1 mm and 0.5 mm, in particular between 0.2 mm and 0.3 mm. The thickness of the deformable membrane 51 is less than the thickness of the support layer 50 and / or the bonding layer 52. Advantageously, the deformable membrane 51 comprises a ceramic material, such as alumina, or a metallic material. The deformable membrane 51 is deformable under the effect of pressure exerted by the fluid F. This deformation is converted into an electrical signal, for example, by a Wheatstone bridge printed on the deformable membrane 51 or by electrodes, depending on the type of pressure sensor.

[0102] The deformable membrane 51 has first and second faces 51a, 51b that are axially opposed. The first face 51a is in contact with the bonding layer 52 and the second face 51b is in contact with the adhesive layer 51'.

[0103] The adhesive layer 51' is located between the plate 39 and the deformable membrane 51. It includes an annular opening 53 centered on the longitudinal axis X. This annular opening 53 is thus aligned with the central orifice 41 of the plate 39. It allows the passage of the fluid F to the deformable membrane 51. The adhesive layer 51' connects the pressure sensor 46 to the support 24 to form a single piece. The adhesive layer 51' comprises, for example, a polymer material such as an epoxy or a silicate.

[0104] The pressure sensor 46 further comprises first, second, and third electrical tracks 54, 55, 56 that are electrically connected to each other. The first electrical track 54 is located on the first face 50a of the support layer 50, and the second electrical track 55 can be located on the second face 50b of the support layer 50 or between the bonding layer 52 and the support layer 50. The third electrical track 56 is located on the first face 51a of the deformable membrane 51. The first, second, and third electrical tracks 54, 55, 56 are connected to each other by an electrical link 57 that extends through the bonding layer 52 and the support layer 50. The first, second, and third electrical tracks 54, 55, 56 can be printed directly onto the support layer 50 and the deformable membrane 51 and / or the bonding layer 52, respectively.

[0105] Each electrical track 54, 55, 56 is electrically conductive and can be in the form of an electrical point or an electrical strip.

[0106] Furthermore, according to the invention, the first electrical track 54 is connected to the thermistor 48 by the electrical conductor(s) 45.

[0107] Advantageously, according to a first embodiment, each electrical conductor 45 comprises a first portion 45' embedded in the plate 39 and extending in a plane substantially parallel to the first and second surfaces 51a, 51b of the deformable membrane 51 and a second portion 45” substantially curved which connects the first portion 45' to the second end 45b of the electrical conductor 45. The first portion 45' is connected to the first end 45a.

[0108] According to this example illustrated in [Fig.1 1] for example, the first end 45a of each electrical conductor 45 is bent and is connected to the first electrical track 54. The connection of the first end 45a to the first electrical track 54 can be direct or indirect via a spring for example (not illustrated).

[0109] Such an example makes it possible to avoid drilling in the support layer 50 for the passage of electrical conductors 45.

[0110] According to another example, the pressure sensor 46 may include at least one hole 58 and advantageously two holes 58. Each hole 58 is made, for example, by laser drilling. Each hole 58 extends longitudinally from the deformable diaphragm 51 to the first electrical track 54. Each electrical conductor 45 extends within a hole 58.

[0111] The measuring device 20 further comprises an electronic signal processing unit 59. The electronic unit 59 is located on the support layer 50. It enables the conditioning of the electrical signals of the measured pressure and temperature, the transmission of these signals, and the protection of these signals.

[0112] The measuring device 20 further includes electrical contacts 60 located on the support layer 50 and which are connected to the electrically conductive tabs 30.

[0113] According to a preferred embodiment, the measuring device 20 further comprises a protective sleeve 61 for the temperature sensor 47. The sleeve 61 is connected to the conduit 40 of the support 24. In particular, the sleeve 61 is connected to the end of the conduit 40. For example, the sleeve 61 is mounted around the closed end of the conduit 40 opposite the plate 39. The sleeve 61 is connected, for example, to the conduit 40 of the support 24 by welding, push-fitting, or screwing.

[0114] The sleeve 61 is centered on the longitudinal axis X. It has a cylindrical wall 62 which is, for example, perforated and hollow. This allows the passage of fluid F through the sleeve 61. The sleeve 61 comprises, for example, a polymeric material.

[0115] The sleeve 61 comprises, for example, a metallic or polymeric material.

[0116] The sleeve 61 can be received in a connector which is screwed into the pipeline 14.

[0117] The temperature sensor 47, and in particular the thermistor 48, is located in the sleeve 61. The second end 45b of each electrical conductor 45 is also located in the sleeve 61.

[0118] The measuring device 20 may further include an insert 63 centered on the longitudinal axis X and mounted between the retaining body 23 and the support 24. In particular, the insert 63 is mounted around the conduit 40 of the support 24 and inside the retaining body 23. The insert 63 is further located axially between the plate 39 of the support 24 and the sleeve 61.

[0119] Insert 63 is preferably threaded.

[0120] The insert 63 extends longitudinally between two ends 64a, 64b. The insert 63 has a central passage 65 extending longitudinally and opening at the ends 64a, 64b of the insert 63. The insert 63 further comprises first and second collars 66a, 66b delimiting between them a groove 67.

[0121] The insert 63 advantageously comprises a metallic material 63, such as aluminum. Such an insert 63 improves the seal between the measuring device 20 and the pipe 14.

[0122] The retaining body 23 cooperates with the insert 63 and together they form a single unit. The insert 63 is, for example, overmolded into the retaining body 23. The transverse wall 34 of the circular portion 32 of the retaining body 23 bears against the first flange 66a and the polygonal portion 33 is engaged in the groove 67.

[0123] To increase the sealing of the measuring device 20, the latter may include a first sealing gasket 68a and / or a second sealing gasket 68b. The first and second gaskets 68a, 68b are annular and centered on the longitudinal axis X.

[0124] The first seal 68a is located axially between the plate 39 and the insert 63. The first seal 68a bears axially on the first collar 66a of the insert 63 and is located inside the transverse wall 34 of the retaining body 23. The first seal 68a is advantageously compressed by the cover 22, which improves the sealing of the measuring device 20.

[0125] The second seal 68 is mounted around the insert 63 and outside the retaining body 23.

[0126] The measuring device 20 of the invention can be applied to any fluid transport pipeline that requires monitoring of parameters, particularly the pressure and temperature of that fluid. The measuring device 20 is thus also applicable to the aeronautical or underwater sectors, and to any sector using a fluid, particularly one under pressure.

Claims

Demands

1. A pressure and temperature measuring device (20) for a fluid (F), the measuring device (20) having a longitudinal axis (X), characterized in that the measuring device (20) comprises: - an annular retaining body (23) extending around the longitudinal axis (X) and comprising an annular housing (37) and a central passage (31) centered on the longitudinal axis (X), - a one-piece measuring assembly (20') comprising: - a support (24) comprising: a flat plate (39) disposed in the annular housing (37) of the retaining body (23), the plate (39) having a central orifice (41) centered on the longitudinal axis (X) for the passage of the fluid (F), and a conduit (40) centered on the longitudinal axis (X) and extending longitudinally from the plate (39) to the outside of the retaining body (23), the conduit (40) having at least one opening (44) opposite the plate (39) for the passage of the fluid (F) in the conduit (40),- a pressure sensor (46) arranged in the annular housing (37) of the retaining body (23), the pressure sensor (46) comprising: a support layer (50), the support layer (50) comprising a first face (50a) having a first electrical track (54) and a second opposite face (50b), and a deformable membrane (51) disposed between the plate (39) and the support layer (50), - a temperature sensor (47) comprising: a thermistor (48) located outside the conduit (40) on the side of the opening (44), and at least one electrical conductor (45) extending along the conduit (40) and connecting the thermistor (48) to the first electrical track (54), the electrical conductor (45) being integrated into the support (24) which is formed in one piece with the electrical conductor (45).

2. Device according to the preceding claim, characterized in that the deformable membrane (51) is connected to the plate (39) by an adhesive layer (51').

3. Device according to the preceding claim, characterized in that the adhesive layer (51') comprises an annular opening (53) centered on the longitudinal axis (X).

4. Device according to any one of the preceding claims, characterized in that the pressure sensor (46) comprises a bonding layer (52) arranged between the support layer (50) and the deformable membrane (51).

5. Device according to any one of claims 2 to 4, characterized in that the bonding layer (52) and / or the adhesive layer (51') comprises a polymer material selected from epoxy or a silicate.

6. Device according to any one of the preceding claims, characterized in that the deformable membrane (51) has first and second faces (51a, 51b) opposite, the second face (51b) being disposed on the plate (39) and the first face (51a) having a third electrical track (56) connected to the first electrical track (54).

7. Device according to any one of the preceding claims, characterized in that the electrical conductor (45) has a first portion (45') embedded in the plate (39) and a first end (45a) connected to the first electrical track (54) and to the first portion (45').

8. Device according to any one of the preceding claims, characterized in that the support layer (50) comprises a ceramic material such as a silicon oxide, or glass or a polymeric material.

9. Device according to any one of the preceding claims, characterized in that it comprises a sleeve (61) connected to one end of the conduit (40), the thermistor (48) being located in the sleeve (61).

10. Device according to any one of the preceding claims, characterized in that it comprises an insert (63) mounted in the retaining body (23) and around the conduit (40), the insert (63) and the retaining body (23) forming a single unit.

11. Device according to the preceding claim, characterized in that a first annular seal (68a) is mounted between the plate (39) and the insert (63).

12. Device according to the preceding claim, characterized in that a second annular seal (68b) is mounted around the insert (63), outside the retaining body (23).