• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    This pressure and temperature determining device comprises a membrane (2) having a contact face (4) with the fluid (F), a pressure determining element (6), a temperature determining element (10) and a support for supporting the temperature determining element (10). The support has an implantation face which is opposite to the contact face (4). The temperature determining element (10) is disposed on the implantation face (12).
    公开号:FR3032272A1
    申请号:FR1550795
    申请日:2015-02-02
    公开日:2016-08-05
    发明作者:Hammouda Chokri Ben；Marc Novellani
    申请人:MGI Coutier SA；
    IPC主号:
    专利说明:

    [0001] The present invention relates to a device for determining pressure and temperature for determining the pressures and temperatures of a fluid flowing for example in a motor vehicle. In addition, the present invention relates to a pressure and temperature sensor comprising such a device for determining pressure and temperature. Furthermore, the present invention relates to a method of manufacturing such a device for determining pressure and temperature. The present invention applies in particular to the field of motor vehicles, in particular commercial vehicles, passenger vehicles and trucks, in order to determine and measure the pressures and temperatures of different fluids flowing in such a vehicle, such as a fuel, oil, an aqueous urea solution (SCR) or air flowing into the air intake circuit. EP0893676A2 illustrates a pressure and temperature sensor comprising a pressure and temperature determining device, which comprises a membrane in contact with the fluid, a temperature determining element and a capacitive type pressure determining element. Since the temperature determining element is immersed in the fluid, the temperature determining element has a very short response time. However, such an arrangement reduces the service life of the pressure and temperature determining device because the temperature determining element is exposed to corrosive fluids, such as a fuel. It is possible to encapsulate the temperature determining element to protect it against the fluid, but this considerably increases the manufacturing cost and increases the response time. In addition, such an assembly requires drilling several passages in the membrane, so as to pass the electrical connection tabs of the temperature determining element, which may weaken the membrane and pollute the pressure determination device and temperature. The present invention is intended in particular to solve, in whole or in part, the problems mentioned above.
    [0002] For this purpose, the subject of the invention is a device for determining pressure and temperature, intended to determine the pressures and temperatures of a fluid, flowing for example in a motor vehicle, the device for determining the pressure and temperature sensor comprising at least: - a membrane having a contact face intended to be in contact with the fluid, - a pressure determining element integral with the membrane and comprising at least one piezoresistive pressure-sensitive track, - an element of temperature determination which is temperature sensitive, and - a support integral with the membrane and configured to support the temperature determining element; the pressure and temperature determining device being characterized in that the support has an implantation face which is opposed to the contact face, the temperature determining element being disposed on the implantation face. Thus, such an assembly of the temperature determining element makes it unnecessary to pierce passages in the membrane, which maintains the mechanical strength of the membrane and which avoids polluting the pressure and temperature determination device. In addition, such mounting of the temperature determining element increases the service life of the pressure and temperature determining device, since the temperature determining element is isolated from the corrosive fluid, such as a fuel. In the present application, the term "determine" and its derivatives means to generate a signal representative of a physical quantity. Thus, a pressure determining element generates signals representative of the pressure, and a temperature determining element generates signals representative of the temperature. A piezoresistive track can form a pressure determining element because, under the effect of a pressure exerted by the fluid on the contact face, the piezoresistive track undergoes an imbalance proportional to this pressure, thus generating a voltage representative of this pressure. Indeed, a piezoresistive component has an electrical resistance that changes as a function of mechanical stress (pressure) experienced by this component.
    [0003] An electronic signal unit can then condition the signals generated by the temperature determining element and the pressure determining element. Depending on the intended application for the pressure and temperature determining device, the electronic unit may provide an analog response or a digital response. According to one variant, the temperature determination element may be arranged indirectly on the implantation face of the support. For example, a layer may be interposed between the implantation face and the temperature determination element, for example a thermally conductive material. According to an advantageous variant, the distance between the implantation face and the temperature determination element is less than 0.2 mm.
    [0004] According to a variant, the face facing the membrane is generally parallel to the contact face. According to a variant, the face facing the membrane completely or partially covers the contact face. According to one variant, the membrane is composed of a ceramic, preferably comprising at least 95% of alumina, the membrane preferably having a thickness of between 0.1 mm and 0.5 mm, that is to say between 100 pm and 500 pm. Thus, such a ceramic allows the membrane to deform rapidly under the effect of the pressure exerted by the fluid, so that the or each piezoresistive track can determine the pressure of the fluid. In addition, such a ceramic allows rapid and precise deposition of piezoresistive (s) and thermistante (s). According to one variant, the membrane is generally flat. Thus, such a membrane has a flat face, which simplifies the deposition of the or each piezoresistive track.
    [0005] According to a variant, the membrane may have a generally elliptical shape, for example circular, or a generally rectangular shape, for example square. According to one variant, the support also supports at least one electronic component, for example an integrated circuit.
    [0006] According to one embodiment, the device for determining pressure and temperature comprises a base forming the support, the base having a first base face oriented towards the membrane and a second base face opposite to the membrane, the second base face forming the implantation face on which is disposed the temperature determining element.
    [0007] Thus, the distance between the fluid and the temperature determining element is limited to the thicknesses of the base and the membrane, which ensures a relatively short response time. According to a variant, the base and the membrane can be manufactured precisely according to the technique known in English as "membrane flush", in which the membrane can be attached to the base by means of a sealing glass or gasket. glass. According to a variant, the device for determining pressure and temperature further comprises a glass joint secured to the base and the membrane. Thus, such a glass gasket makes it possible to seal a chamber surrounding the pressure determining element. To make this glass joint, it is necessary to have a glass paste (silica) between the membrane and the base, then heat to the melting temperature of the glass. According to a variant, the base comprises at least 95% alumina, the base being configured to define a chamber around the pressure determining element. Thus, such a base defining the chamber makes it possible to measure relative or absolute pressure. According to a variant, the base has at least one venting hole opening on the one hand on the membrane and on the other hand on the outside of the device for determining pressure and temperature. Thus, such a venting hole makes it possible to measure relative pressures. Alternatively, the base is configured so that the chamber is sealed. In other words, the base has no vent hole. Thus, such a base makes it possible to measure absolute pressures. According to one embodiment, the pressure and temperature determining device comprises a printed circuit substrate forming the support, the printed circuit substrate having a first substrate face facing the membrane and a second substrate face opposite to the substrate. membrane, the second substrate face forming the implantation face on which is disposed the temperature determining element.
    [0008] Thus, the membrane can be manufactured according to the monolithic technique. Thus the membrane is integral with the base, so that the membrane and the base form a monolithic assembly lacking for example glass seal. Then, the printed circuit substrate is assembled to the monolithic membrane. In practice, the printed circuit substrate is sometimes referred to as an integrated circuit or electronic card or else designated by the English term "Printed Circuit Board" abbreviated as "PCB". According to one variant, the printed circuit substrate is flexible. Alternatively, the printed circuit substrate is rigid. According to one embodiment, the membrane forms the support, and the membrane further has a dry face which is opposite to the contact face, the dry face forming the implantation face. In this embodiment, the support is formed by the membrane itself. The contact face forms the other side of the support. Thus the membrane support has the contact face and the implantation face opposite to the contact face. Thus, the response time of the temperature determining element is very low, while the accuracy of the temperature determining element is very high. Indeed, the membrane has a small thickness, typically between 100 pm and 500 pm, which allows a rapid thermal transfer through the membrane. This thermal transfer is all the faster as there is no air or vacuum between the membrane and the temperature determination element. Alternatively, the temperature determining element may be attached indirectly to the implantation face of the membrane. For example, a layer may be interposed between the implantation face and the temperature determining element. According to one embodiment, the temperature determining element is located, in projection on a face of the membrane opposite to the contact face, substantially in line with a peripheral path delimiting the pressure determining element. In other words, the peripheral path delimits an active pressure measurement zone, which corresponds to a zone of the membrane which deforms significantly under the effect of the pressure of the fluid on the contact face.
    [0009] Thus, such an implantation of the temperature determination element makes it possible to maximize the accuracy of the temperature measurement, while minimizing the response time of the temperature determination element.
    [0010] In practice, when the device for determining pressure and temperature is incorporated in a pressure and temperature sensor comprising a seal, for example an O-ring, the peripheral pattern is included in a perimeter delimited by the internal edge of the seal. The inner edge of the seal defines the contour of a pressure measuring cavity in which the fluid contacts the membrane. According to a variant, the pressure determining element has dimensions of between 3 mm and 10 mm. In a variant where the pressure determining element has a generally circular perimeter, the diameter of the perimeter is between 3 mm and 10 mm. Alternatively, the determination element may have a generally rectangular-shaped perimeter, the long side of which is between 3 mm and 10 mm. According to a variant, the pressure determining element extends over an area of between 7 mm 2 and 100 mm 2, for example approximately equal to 38 mm 2.
    [0011] Advantageously, the distance between the temperature determination element and the peripheral path, measured in orthogonal projection on the implantation face, is less than 2 mm. According to one variant, the temperature determination element is disposed outside the peripheral path. Alternatively, for example as a function of implantation constraints, the temperature determining element is disposed within the peripheral path. According to one embodiment, a distance between the peripheral pattern and the projection of the geometric center of the temperature determining element on the face of the membrane opposite the contact face is between -25% and + 25% of the maximum dimension of the pressure determining element. The aforesaid distance is measured following or parallel to a direction carrying this maximum dimension. Thus, the temperature determining element is located substantially in line with the peripheral path, which increases the accuracy of the measurements made by the temperature determining element. Indeed, the area delimited by the peripheral path is part of the portion of the membrane that heats the fastest because it is directly in contact with the fluid. Moreover, this zone delimited by the peripheral path allows rapid conduction of the heat up to the temperature determining element, in particular by avoiding or bypassing the central region formed of air or vacuum, for example in so-called to "membrane flush". According to one embodiment, the temperature determining element is an electronic component, for example an electronic dipole. In this application, the term "electronic component" refers to an element intended to be assembled with other elements to form an electronic circuit. Thus, such an electronic component is inexpensive because it is widely available commercially. In addition, such an electronic component makes it possible to generate easily exploitable signals by a central unit of the motor vehicle. In other words, the signals generated by such an electronic component are compatible with the central units of the current motor vehicles. In addition, such an electronic component simplifies the commissioning of the pressure and temperature determining device, since the electronic component does not generally require calibration or calibration. According to one embodiment, the temperature determining element comprises a thermistor, preferably selected from the group consisting of a Negative Temperature Coefficient thermistor, a Positive Temperature Coefficient thermistor and a thermometer. platinum resistance. Thus, such a thermistor generates measurement signals which can be exploited by the existing central units in the current motor vehicles without specific treatment of these measurement signals. Alternatively, the platinum resistance thermometer may have a resistance of 100 ohms (Pt100) or 1000 ohms (Pt1000). Alternatively, the pressure and temperature determining device further comprises a thermally insulating material arranged to completely or partially cover the temperature determining element. The thermally insulating material may be a thermally insulating resin, for example an epoxy resin, mono- or bi-component. Thus, such a thermally insulating material makes it possible to minimize the thermal losses towards the air situated above the temperature determining element, which reduces the duration of the temperature measurement, since the temperature of the temperature determination element temperature is quickly stabilized. Thus, the temperature determining element can provide more accurate measurements because the thermally insulating material reduces the influence of the ambient temperature.
    [0012] According to a variant, the device for determining pressure and temperature further comprises a thermally conductive material disposed between the temperature determining element and the implantation face. Thus, such a thermally conductive material maximizes the amount of heat transmitted by the membrane to the temperature determining element, which reduces the temperature measurement time and increases the accuracy of the temperature determining element. According to one embodiment, the device for determining pressure and temperature further comprises a bonding product arranged to fix the temperature determining element on the implantation face, the joining product being selected from the group consisting of a solder paste, a solder metal and a solder metal. Thus, such a joining product makes it possible to fix the temperature determination element on the implantation face by gluing or by a surface mounting technique (sometimes referred to as "Surface Mount Technology" abbreviated as "SMT "). According to a variant, said at least one piezoresistive track is printed on the membrane, preferably by screen printing. Thus, the device 30 for determining pressure and temperature has a relatively low cost, because the piezoresistive tracks (s) are derived from prints, which allows to simply perform very precise printed tracks. According to a variant, said at least one piezoresistive track is composed of at least one material selected from the group consisting of 35 mineral matrices and organic polymer matrices. Thus, such a material makes it possible to confer on the piezoresistive track good pressure determination properties, especially in terms of the coefficient of measurement, linearity and hysteresis of the response curve, of the resolution, of the accuracy, of the response time. . For example, the or each piezoresistive track may be ruthenate (ruthenium oxide).
    [0013] According to a variant, said at least one piezoresistive track has a thickness of between 1 μm and 100 μm. According to a variant, said at least one piezoresistive track forms several pressure gauges distant from each other, the pressure and temperature determination device further comprising conductive tracks connecting the pressure gauges so as to form an electrical measuring circuit pressure, for example a Wheatstone bridge. Thus, such pressure gauges, coupled to such an electrical pressure measuring circuit can determine the pressure with high accuracy and a short response time. These conductive tracks may be composed of a silver-palladium alloy (Pd-Ag). In the present application, the terms "conduct", "connect", "connect" and their derivatives refer to electrical conduction. Furthermore, the present invention relates to a pressure and temperature sensor, for measuring pressures and temperatures of a fluid flowing for example in a motor vehicle, the pressure and temperature sensor comprising at least a device for determining pressure and temperature according to the invention, a connecting member configured to fluidically connect the contact face to a channel of the fluid, and an electronic unit configured to condition signals and connected to the pressure determining element. Thus, such a pressure and temperature sensor has an extended service life and generates measurement signals which can be operated by existing central units in current motor vehicles without specific treatment of these measurement signals. In addition, such a combined pressure and temperature sensor is reliable, accurate and compact compared to a combined pressure and temperature sensor of the prior art. In the present application, the term "sensor" refers to a set whose response, numerical or analog, is representative of the measurement of physical quantities, in this case of pressure and temperature. Alternatively, the electronic unit is further connected to the temperature determining element.
    [0014] According to one embodiment, the pressure and temperature sensor further comprises a seal, for example an O-ring, which is compressed between the contact face and the connection member, the connection member having a passage for the fluid having a similar section to the shape of the joint after compression of the seal.
    [0015] In one embodiment, the seal defines a perimeter surrounding the peripheral trace. Thus, such a seal may define a perimeter surrounding the peripheral pattern, and thus the pressure determining member, and within which the temperature determining member may be disposed. According to a variant, the seal is an O-ring and the passage for the fluid has a generally circular section whose diameter is substantially equal to the internal diameter of the O-ring after compression of the O-ring. According to a variant, the connection member has a passage for the fluid having dimensions of between 2 mm and 8 mm. Thus, such dimensions make it possible to minimize the temperature response time while maintaining a static pressure measurement. According to a variant, the passage for the fluid is arranged perpendicularly to the flow direction of the fluid in the conduit on which the sensor is mounted. Thus, it is possible to measure a static pressure. Alternatively, the passage for the fluid may be arranged obliquely, for example at 45 degrees, to the flow direction of the fluid in the conduit on which the sensor is mounted. Alternatively, the outer surface of the pressure and temperature sensor has a coating of electrically conductive material. Thus, such a conductive coating can form an electromagnetic shield, in order to meet the requirements of electromagnetic compatibility (EMC). Moreover, the subject of the present invention is a manufacturing method, for manufacturing a device for determining pressure and temperature according to the invention, the manufacturing method comprising the steps of: depositing conductive tracks on the membrane, preferably through a first screen printing screen, - depositing said at least one piezoresistive track, preferably through a second screen printing screen, so as to secure said at least one piezoresistive track to the membrane, - provide a support integral with the membrane , the support having an implantation face which is opposite to the contact face, and - arranging the temperature determining element on said implantation face. The order of the steps of this manufacturing process can be modified without departing from the scope of the present invention. According to a variant, after at least one of said deposition steps, the manufacturing method further comprises a step consisting in carrying out an oven drying and a heat treatment adapted to evaporate the solvents. Alternatively, the manufacturing method further comprises a step of adjusting said at least one piezoresistive track by laser adjustment (a technique known as "laser trimming"). Thus, such a laser setting makes it possible to define a pressure determining element with high accuracy, which increases the performance of the pressure and temperature determination device. Furthermore, the present invention relates to a motor vehicle comprising at least one such pressure sensor and temperature. The embodiments and variants mentioned above may be taken in isolation or in any technically permissible combination. The present invention will be well understood and its advantages will also emerge in the light of the description which follows, given solely by way of nonlimiting example and with reference to the appended figures, in which identical reference signs correspond to elements structurally and / or functionally similar. The attached figures are: FIG. 1 is a diagrammatic sectional view of a pressure and temperature determination device according to a first embodiment of the invention; FIG. 2 is a diagrammatic view from above, along arrow II in FIG. 1, of the pressure and temperature determination device of FIG. 1; - Figure 3 is a schematic sectional view of a pressure and temperature determination device according to a second embodiment of the invention; - Figure 4 is a schematic sectional view of a pressure and temperature determination device according to a third embodiment of the invention; FIG. 5 is a schematic sectional view of a pressure and temperature sensor comprising the pressure and temperature determination device of FIG. 1; and FIG. 6 is a logic diagram illustrating a manufacturing method according to the invention. Figures 1 and 2 illustrate a pressure and temperature determination device 1 according to a first embodiment of the invention. The device for determining pressure and temperature 1 belongs to a pressure and temperature sensor which is intended to equip a motor vehicle, not shown. The device for determining pressure and temperature 1 is intended to determine pressures, symbolized by the arrows P in FIG. 1, and to determine the temperatures of a fluid that flows into the motor vehicle and whose flow is through example symbolized by an arrow F.
    [0016] The device for determining pressure and temperature 1 comprises a membrane 2 which has, on the one hand, a contact face 4 intended to be in contact with the fluid F, and, on the other hand, a dry face 5, which is opposed to the contact face 4. In the example of Figure 1, the membrane 2 is composed of a ceramic comprising 96% alumina. The membrane 2 here has a generally flat shape. The membrane 2 here has a thickness of about 0.25 mm. The pressure and temperature determining device 1 further comprises a pressure determining element 6 which is sensitive to the pressure P and which is integral with the membrane 2. The pressure determining element 6 comprises piezoresistive tracks 8 .
    [0017] In this case, the piezoresistive tracks 8 are printed by screen printing on the dry face 5. The piezoresistive tracks 8 each have a thickness of about 10 μm. The membrane 2 has a certain flexibility, so as to transmit the pressure P to the piezoresistive tracks 8.
    [0018] The piezoresistive tracks 8 form pressure gauges distant from each other. The pressure and temperature determination device 1 further comprises unrepresented conductive tracks which connect these pressure gauges so as to form an electrical pressure measurement circuit, here formed in a Wheatstone bridge. This Wheatstone bridge operates in a conventional manner and is known per se. The pressure and temperature determining device 1 further comprises a temperature determining element 10. The temperature determining element 10 here comprises a Negative Temperature Coefficient (NTC) thermistor.
    [0019] In addition, the device for determining pressure and temperature 1 comprises a support integral with the membrane 2 and configured to support the temperature determining element 10. The support has an implantation face which is opposite to the contact face 4 and on which is disposed the temperature determining element 10. The distance between the implantation face 12 and the temperature determining element is here approximately equal to 0.05 mm. Alternatively, the temperature determining element may be in direct contact with the implantation face. In the example of FIG. 1, the device for determining pressure and temperature 1 comprises a base 14 which forms the support configured to support the temperature determining element 10. The support formed by the base 14 is integral with the membrane 2. The base 14 may further support electronic components, for example an integrated circuit 16 (sometimes referred to by the acronym ASIC of the English term "Application-Specific Integrated Circuit"). The base 14 may be composed of a ceramic, for example comprising 96% of alumina. The base 14 has, on the one hand, a first base face 14.1 which is oriented towards the membrane 2 and, on the other hand, a second base face 14.2 which is opposite the membrane 2. The second face 14.2 base forms the implantation face 12, on which is disposed the temperature determination element 10. The first base face 14.1 is generally parallel to the contact face 4. The first base face 14.1 covers partially here the contact face 4. In addition, the pressure and temperature determination device 1 comprises a glass seal 15 disposed between the membrane 2 and the base 14. To manufacture the glass gasket, it is possible for example to have a glass paste between the membrane 2 and the base 14, and then heat to the melting temperature of the glass. In use, when the fluid F is in contact with the contact face 4, the membrane 2 is brought to the temperature of the fluid and then transfers the heat of the fluid F to the base 14, which carries the temperature determining element 10 at a temperature representative of the fluid F. The temperature determining element 10 generates a signal, analog or digital, representative of the fluid temperature F. This analog or digital signal can be generated directly by the temperature determination element 10 or indirectly, for example via the integrated circuit 16. The pressure and temperature determining device 1 further comprises a securing product arranged to fix the temperature determining element 10 on the face of the device. implantation 12.
    [0020] In this case, the solidifying product is a solder paste. This solidarization product fixes the temperature determining element 10 on the implantation face 12 by a surface mounting technique (sometimes referred to as "Surface Mount Technology" abbreviated as "SMT"). As shown in Figure 2, the base 14 comprises one or more electronic components on the second base face 14.2, for example the ASIC integrated circuit 16. The base 14 is secured to the membrane 2. In addition, the base 14 is electrically connected to the membrane 2. Moreover, the temperature determination element 10 is located, in projection on the dry face 5, substantially in line with a peripheral path 20 which delimits the pressure determining element 6. In the example of FIGS. 1 and 2, the pressure determining element 6 occupies a space of substantially circular shape, so that the peripheral path 20 substantially forms a circle. This circle here has a diameter of approximately 5 mm.
    [0021] A distance D20 between the peripheral pattern 20 and the projection of the geometric center of the temperature determining element 10 on the face of the membrane opposite the contact face 4 is less than 25% of the maximum dimension of the element. pressure determination 6.
    [0022] When the pressure and temperature determination device 1 is assembled in a pressure and temperature sensor 51, visible in FIG. 5 and comprising a seal 22 compressed against the contact face 4, the seal 22 defines the portion of the membrane in contact with the fluid F. The inner edge 22.1 of the seal 22 defines a perimeter surrounding the peripheral pattern 20. In the example of Figure 1, the projection of the geometric center of the temperature determining element 10 on the face of the membrane opposite the contact face 4 is located between the peripheral pattern 20 and the perimeter defined by the inner edge 22.1 of the seal 22 in the compressed state, therefore after assembly of the pressure and temperature determination device 1. The FIG. 3 illustrates a device for determining pressure and temperature 1 according to a second embodiment of the invention. Insofar as the pressure and temperature determination device 1 of FIG. 3 is similar to the pressure and temperature determination device 1 of FIGS. 1 and 2, the description of the sensor 1 given above in relation to FIGS. 1 and 2 may be transposed to the pressure and temperature determining device 1 of FIG. 3, with the exception of the notable differences set forth below. The pressure and temperature determining device 1 of FIG. 3 differs from the pressure and temperature determining device 1 of FIGS. 1 and 2, since the pressure and temperature determining device 1 of FIG. circuit board 114 forming the support, and since the pressure and temperature determining device 1 of Figure 3 does not include a base. The printed circuit substrate 114 has, on the one hand, a first substrate face 114.1 which is oriented towards the membrane 2, and, on the other hand, a second substrate face 114.2 which is opposed to the membrane 2. second substrate face 114.2 forms the implantation face 12 on which the temperature determining element 10 is arranged.
    [0023] Moreover, the pressure and temperature determining device 1 of FIG. 3 differs from the pressure and temperature determination device 1 of FIGS. 1 and 2, since the projection of the geometric center of the temperature determining element 10 over the face of the membrane opposite the contact face 4 is located at the right of the seal 22. Furthermore, the pressure and temperature determination device 1 of FIG. 3 differs from the pressure and temperature determination device 1 of the figures 1 and 2, because the membrane 2 has a peripheral wall 2.1 which extends around a central portion 2.2 of flat shape, while the membrane 2 of Figures 1 and 2 is generally flat without peripheral wall. The peripheral wall 2.1 serves in particular to position and block the seal 22. As in the first embodiment illustrated in FIGS. 1 and 2, the pressure determining element 6 occupies a substantially circular shaped space 15, as shown in FIG. Figure 3, so that the peripheral pattern 20 substantially forms a circle. As in the first embodiment illustrated in FIGS. 1 and 2, a distance D20 between the peripheral pattern 20 and the projection of the geometric center of the temperature determining element 10 on the face of the membrane opposite to the contact face , is less than 25% of the maximum dimension of the pressure determining element 6. The projection of the geometric center of the temperature determining element 10 is here outside the peripheral path 20. FIG. a pressure and temperature determining device 1 according to a third embodiment of the invention. Insofar as the pressure and temperature determination device 1 of FIG. 4 is similar to the pressure and temperature determination device 1 of FIGS. 1 and 2, the description of the sensor 1 given above in relation to FIGS. 1 and 2 may be transposed to the pressure and temperature determination device 1 of FIG. 4, with the exception of the notable differences set forth below. The pressure and temperature determining device 1 of FIG. 4 differs from the pressure and temperature determining device 1 of FIGS. 1 and 2 essentially because the membrane 2 forms the support, while the support is formed by the base 14 in the embodiment of Figures 1 and 2.
    [0024] In addition, the membrane 2 has a dry face 5 which is opposite to the contact face 4 and which forms the implantation face on which the temperature determination element 10 is arranged. As in the example of FIG. 1, the piezoresistive tracks 8 are printed by screen printing on the dry face 5 in order to form the pressure determining element 6. FIG. 5 illustrates a pressure and temperature sensor 51 intended to measure pressures P and temperatures of a fluid F flowing for example in a motor vehicle.
    [0025] The pressure and temperature sensor 51 comprises the pressure and temperature determination device 1 of FIG. 4, as well as a connection member 52 configured to fluidically connect the contact face 4 to a line 58 of the fluid F. Line 58 serves to transfer the fluid F between two components of the motor vehicle. In addition, the pressure and temperature sensor 51 comprises an electronic unit 54 configured to condition signals generated by the pressure determining element 6 and, if necessary, by the temperature determining element 10. The electronic unit 54 is connected on the one hand to the pressure determining element 6 and on the other hand to the temperature determining element 10. In the example of FIG. 5, the electronic unit 54 is formed on a circuit printed which is reported in hybrid technology on the base 4. The electronic unit 54 may comprise a not shown signal amplifier. The electronic unit 54 can deliver an analog or digital response on the output terminals of a connector 56. The pressure and temperature sensor 51 further comprises the seal 22, here an O-ring, which is compressed between the contact face 4 and the connecting member 52, the connecting member having a passage 57 for the fluid F having a section similar to the shape of the seal 22 after compression of the seal 22. The inner edge 22.1 of the seal 22 defines the contour of a pressure measuring cavity in which the fluid F comes into contact with the membrane 2. The passage 57 of the connecting member 52 here has a generally circular section 35, whose diameter is substantially equal to the internal diameter of the seal 22 after its compression, which avoids or limits the appearance of fluid stagnation zones F. The diameter of the passage 57 is here about 5.5 mm. In use, the fluid F flows from the pipe 58 through the passage 57 and up to the contact face 4. Moreover, as shown in FIG. 5, the pipe 58 is of the "fir-fitting" type, because it has annular ribs for fastening a not shown flexible hose through which the fluid flows. The connecting member 52 is configured to be connected transversely, here perpendicularly, to the flow direction of the fluid F in the pipe 58 belonging to the vehicle 10 automobile. Thus, the pressure and temperature sensor disturbs as little as possible the flow of the fluid F. The connecting member 52 and the connector 56 are here composed of a polyamide (PA). The connecting member 52 is here charged with a conductive material such as a charge of carbon nanotubes, carbon black or other electrically conductive charge, which avoids the accumulation of electrostatic charges. The outer surface of the pressure and temperature sensor 51 may include a coating of electrically conductive material, which forms an electromagnetic shield. FIG. 6 illustrates a manufacturing method 500, for manufacturing the device for determining pressure and temperature 1. This manufacturing method 500 comprises the steps: - 502) depositing on the membrane conductive tracks, preferably through a first screen-printing screen, - 504) depositing said at least one piezoresistive track 8, preferably through a second screen printing screen, so as to secure said at least one piezoresistive track 8 to the membrane 2, - 505) to provide a solidarity support with the membrane 2, the support having an implantation face 12 which is opposite to the contact face 4, and 30 - 506) arranging the temperature determining element 10 on said implantation face 12. The manufacturing method 500 further comprises assembling steps of securing the membrane 2 and the glass seal 15 on the base 14.
    [0026] The manufacturing method 500 further comprises a step 508) of adjusting the piezoresistive tracks 8 by laser adjustment (a technique known as "laser trimming"). After each of the deposition steps 502), 504) and 506, the manufacturing method 500 further comprises steps which respectively consist in carrying out a baking and a heat treatment adapted to evaporate the solvents used during the deposition steps 502) , 504) and 506). After manufacturing the pressure and temperature determining device, it can be assembled in the pressure and temperature sensor 51, for example by means of laser welds. In use, as shown in FIG. 5, fluid F flows into line 58. In use, fluid F flows from line 58 through passage 57 to contact face 4. After the fluid F has come into contact with the contact face 4, the membrane 2 transmits the fluid pressure F to the piezoresistive tracks 8 and the temperature determining element 10 is raised to the temperature of the membrane 2, which is representative of the temperature of the fluid F. The pressure and temperature determination device 1 thus determines the pressure P and the temperature of the fluid F. Then, the electronic unit 54 collects and processes the signals emitted by the determination device This processing 20 may consist in amplifying these signals by means of an application-specific integrated circuit (ASIC). After this treatment, the electronic unit 54 generates the response of the pressure and temperature sensor 51. This response, analog or digital, can be read by a central unit of the motor vehicle, in order to know the pressure P and the temperature of the vehicle. F. Of course, the invention is not limited to the particular examples described in the present application. Other embodiments within the scope of those skilled in the art can also be envisaged without departing from the scope of the invention defined by the claims below.
    权利要求:
    Claims (13)
    [0001]
    REVENDICATIONS1. A pressure and temperature determination device (1) for determining pressures (P) and temperatures of a fluid (F) flowing for example in a motor vehicle, the pressure and temperature determining device (1) comprising at least: - a membrane (2) having a contact face (4) intended to be in contact with the fluid (F), - a pressure determining element (6) integral with the membrane (2). ) and comprising at least one piezoresistive piezoresistive track (8) responsive to pressure (P), a temperature sensing element (10) which is temperature sensitive, and a support integral with the diaphragm (2) and configured to Supporting the temperature determining element (10); the pressure and temperature determining device (1) being characterized in that the support has an implantation face which is opposite to the contact face (4), the temperature determining element (10) being arranged on the implantation face (12). 20
    [0002]
    2. Device for determining pressure and temperature (1) according to claim 1, comprising a base (14) forming the support, the base (14) having a first base face (14.1) facing the membrane (2). ) and a second base face (14.2) opposite the diaphragm (2), the second base face (14.2) forming the implantation face (12) on which the temperature determining element ( 10).
    [0003]
    A pressure and temperature determining device (1) according to claim 1, comprising a printed circuit substrate (114) forming the support, the printed circuit substrate (114) having a first substrate face (114.1) oriented to the diaphragm (2) and a second substrate face (114.2) opposite the diaphragm (2), the second substrate face (114.2) forming the implantation face (12) on which the temperature (10).
    [0004]
    4. Pressure and temperature determination device (1) according to claim 1, wherein the membrane forms the support, and in which the membrane further has a dry face which is opposite to the contact face, the dry face forming the implantation face.
    [0005]
    Pressure and temperature determining device (1) according to any one of the preceding claims, wherein the temperature determining element (10) is located, in projection on a face of the membrane (2) opposite to the contact face (4), substantially in line with a peripheral path (20) delimiting the pressure determining element (10).
    [0006]
    The pressure and temperature determining device (1) according to claim 5, wherein a distance (D20) between the peripheral pattern (20) and the projection of the geometric center of the temperature determining element (10) on the face of the membrane (2) opposite to the contact face (4) is between -25% and + 25% of the maximum dimension of the pressure determining element (6).
    [0007]
    The pressure and temperature determining device (1) according to any one of the preceding claims, wherein the temperature determining element (10) is an electronic component, for example an electronic dipole.
    [0008]
    The pressure and temperature determining device (1) according to claim 7, wherein the temperature determining element (10) comprises a thermistor, preferably selected from the group consisting of a Negative Temperature Coefficient thermistor. , a Positive Temperature Coefficient thermistor and a platinum resistance thermometer.
    [0009]
    9. A pressure and temperature determination device (1) according to any one of the preceding claims, further comprising a securing product arranged to fix the temperature determining element on the implantation face, the product bonding member being selected from the group consisting of a solder paste, a solder metal and a solder metal.
    [0010]
    10. Pressure and temperature sensor (51) for measuring pressures (P) and temperatures of a fluid (F) flowing for example in a motor vehicle, the pressure and temperature sensor (51) comprising at least: a pressure and temperature determining device (1) according to any one of the preceding claims, - a connecting member (52) configured to fluidically connect the contact face (4) to a pipe of the fluid ( F), and - an electronic unit (54) configured to condition signals and connected to the pressure determining element (6).
    [0011]
    The pressure and temperature sensor (51) according to claim 10, further comprising a seal (22), for example an O-ring, which is compressed between the contact face (4) and the connecting member (52). ), the connecting member (52) having a passage (57) for the fluid (F) having a section similar to the shape of the seal (22) after compression of the seal (22).
    [0012]
    The pressure and temperature sensor (51) of claim 11, wherein the seal (22) defines a perimeter surrounding the peripheral pattern (20).
    [0013]
    13. Manufacturing method (500), for manufacturing a pressure and temperature determination device (1) according to any one of claims 1 to 9, the manufacturing method (200) comprising the steps of: - 502) depositing on the membrane (2) conductive tracks, preferably through a first screen screen, - 504) depositing said at least one piezoresistive track (8), preferably through a second screen screen, so as to secure said at least one piezoresistive track (8) to the membrane (2), - 505) to provide a support integral with the membrane (2), the support having an implantation face (12) which is opposite to the contact face (4) ), and 25 - 506) arranging the temperature determining element (10) on said implantation face (12).
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    同族专利:
    公开号 | 公开日
    CN105841737A|2016-08-10|
    CN105841737B|2020-02-07|
    US20160223378A1|2016-08-04|
    FR3032272B1|2020-06-05|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US4040297A|1974-12-02|1977-08-09|U.S. Philips Corporation|Pressure transducer|
    WO2008036705A2|2006-09-19|2008-03-27|Rosemount Aerospace Inc.|Transducer for use in harsh environments|
    FR3017211A1|2014-02-05|2015-08-07|Coutier Moulage Gen Ind|PRESSURE AND TEMPERATURE DETERMINATION DEVICE, PRESSURE AND TEMPERATURE SENSOR COMPRISING SUCH A DEVICE AND METHOD OF MANUFACTURING SUCH A DEVICE|
    US7152478B2|2000-07-20|2006-12-26|Entegris, Inc.|Sensor usable in ultra pure and highly corrosive environments|
    US6698294B2|2000-09-07|2004-03-02|Vega Grieshaber Kg|Pressure cell with temperature sensors and pressure measuring method|
    EP1946099A2|2005-09-02|2008-07-23|ABB, Inc.|Modular gas chromatograph|
    ITMI20120456A1|2012-03-23|2013-09-24|Microtel Tecnologie Elettroniche S P A|CERAMIC PRESSURE SENSOR AND RELATIVE PRODUCTION METHOD, AND TRANSDUCER THAT INCORPORATES A CERAMIC PRESSURE SENSOR|DE102014114764A1|2014-10-13|2016-04-14|Endress + Hauser Gmbh + Co. Kg|Ceramic pressure sensor and method for its manufacture|
    JP2020515360A|2016-12-22|2020-05-28|サンヴィタ メディカル エルエルシー|Continuous glucose measuring system and method|
    US10545064B2|2017-05-04|2020-01-28|Sensata Technologies, Inc.|Integrated pressure and temperature sensor|
    法律状态:
    2015-12-30| PLFP| Fee payment|Year of fee payment: 2 |
    2016-08-05| PLSC| Publication of the preliminary search report|Effective date: 20160805 |
    2017-01-25| PLFP| Fee payment|Year of fee payment: 3 |
    2018-01-25| PLFP| Fee payment|Year of fee payment: 4 |
    2020-01-27| PLFP| Fee payment|Year of fee payment: 6 |
    2020-05-01| CD| Change of name or company name|Owner name: AKWEL, FR Effective date: 20191127 |
    2021-01-26| PLFP| Fee payment|Year of fee payment: 7 |
    2022-01-25| PLFP| Fee payment|Year of fee payment: 8 |
    优先权:
    申请号 | 申请日 | 专利标题
    FR1550795|2015-02-02|
    FR1550795A|FR3032272B1|2015-02-02|2015-02-02|PRESSURE AND TEMPERATURE DETERMINATION DEVICE, PRESSURE AND TEMPERATURE SENSOR COMPRISING SUCH A DEVICE AND METHOD FOR MANUFACTURING SUCH A DEVICE|FR1550795A| FR3032272B1|2015-02-02|2015-02-02|PRESSURE AND TEMPERATURE DETERMINATION DEVICE, PRESSURE AND TEMPERATURE SENSOR COMPRISING SUCH A DEVICE AND METHOD FOR MANUFACTURING SUCH A DEVICE|
    US15/013,105| US20160223378A1|2015-02-02|2016-02-02|Pressure and temperature determining device, a pressure and temperature sensor comprising such a device and a method for manufacturing such a device|
    CN201610073656.5A| CN105841737B|2015-02-02|2016-02-02|Pressure and temperature determining device, pressure and temperature sensor comprising such a device, and method for manufacturing such a device|
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