Pressure-temperature sensor

Abstract

To provide a pressure-temperature sensor that can accurately measure pressure.SOLUTION: A pressure-temperature sensor comprises: a sensor body 15; a diaphragm 21 that defines a storage space R with the sensor body 15; and a transmission body S that is filled into the storage space R. A pressure measuring body 16 and a temperature measuring body 17 are arranged in the storage space R. A buffer member 20 is formed with a first through hole 202 in the radial center of the buffer member 20. The pressure measuring body 16 and the temperature measuring body 17 are arranged opposite to each other across the axis of the first through hole 202. A diaphragm cover 22 is formed with a second through hole 22a that penetrates the diaphragm cover 22 in the axial direction at a position separate from the radical center of the diaphragm cover 22.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a pressure temperature sensor capable of measuring the pressure and temperature of a fluid to be measured.

Background Art

[0002] In various fields, pressure and temperature are used for equipment operation, maintenance, etc. In many cases, both pressure and temperature are used. To meet the requirement of obtaining both pressure and temperature simultaneously, a pressure temperature sensor is used. The pressure temperature sensor includes a pressure measuring body that outputs a pressure signal corresponding to the pressure of the fluid to be measured, and a temperature measuring body that outputs a temperature signal corresponding to the temperature of the fluid to be measured, and can transmit the pressure signal and the temperature signal to an external device.

[0003] In such a pressure temperature sensor, the pressure measuring body and the temperature measuring body are arranged in the fluid to be measured and may be damaged by chemical and mechanical influences from the fluid to be measured. Therefore, an isolation type pressure temperature sensor in which the pressure measuring body and the temperature measuring body are indirectly in contact with the fluid to be measured is widely used.

[0004] In the isolation type pressure temperature sensor, for example, the pressure measuring body and the temperature measuring body are arranged in an accommodation space defined by a sensor body and a diaphragm, and the accommodation space is filled with a transmission body. The pressure measuring body outputs a pressure signal corresponding to the pressure of the transmission body that has received the pressure of the fluid to be measured via the diaphragm. The temperature measuring body outputs a temperature signal corresponding to the temperature of the transmission body that has received the temperature of the fluid to be measured via the diaphragm. Thereafter, the pressure signal and the temperature signal are converted into a pressure measurement value and a temperature measurement value by an integrated circuit provided on a substrate or the like.

[0005] The pressure and temperature sensor shown in Patent Document 1, which is an example of a pressure and temperature sensor with such an isolation method, has a sensor chip that integrally includes a pressure measurement body and a temperature measurement body disposed in an accommodation space filled with a transmission medium such as silicone oil. The sensor chip is of a semiconductor diaphragm type equipped with a bridge circuit. When pressure is applied to the sensor chip, the intermediate voltage of the bridge circuit that functions as a pressure measurement body changes, and the sensor chip outputs a pressure signal corresponding to this change. Also, when the temperature of the sensor chip changes, the voltage across the bridge circuit that functions as a temperature measurement body changes, and the sensor chip outputs a temperature signal corresponding to this change.

[0006] Thus, in the case of a pressure and temperature sensor such as that of Patent Document 1, pressure and temperature can be measured by a sensor chip that integrally includes a pressure measurement body and a temperature measurement body. Therefore, it is possible to miniaturize. However, since two types of measured values are measured with an integrated sensor chip, the structure of the pressure and temperature sensor such as that of Patent Document 1 is limited. Furthermore, the pressure change of the transmission medium affects the temperature measurement body. Similarly, the temperature change of the transmission medium affects the pressure measurement body. Due to these, the pressure and temperature sensors such as that of Patent Document 1 could not measure accurate values with each measurement body.

[0007] Therefore, for a pressure and temperature sensor such as that of Patent Document 1, it is difficult to correct, for example, the influence of temperature on pressure measurement according to the temperature signal. From this, the measured pressure measurement value and temperature measurement value lacked accuracy. Incidentally, it is also possible to obtain accurate pressure measurement values and temperature measurement values by previously obtaining the relationship between these pressures and temperatures through calibration. However, since the sensor chip is manufactured using a semiconductor process, the variation between production lots is very large. Therefore, since the sensor chip requires calibration for pressure and temperature for each solid, there is also the problem that it is very time-consuming.

[0008] In the pressure temperature sensor shown in Patent Document 2, which is another example of a pressure temperature sensor, the pressure measuring body and the temperature measuring body are separate bodies. Specifically, the pressure measuring body is disposed in an accommodation space filled with a transmission body. The temperature measuring body is disposed so as to protrude from the center of the diaphragm toward the fluid to be measured. A thermistor disposed in a cap-shaped storage portion is filled and fixed with a resin having a high thermal conductivity, thereby constituting the temperature measuring body.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0010] In a pressure temperature sensor such as that of Patent Document 2 as described above, the pressure measuring body and the temperature measuring body are separate bodies and can output a pressure signal or a temperature signal individually. Therefore, in a pressure temperature sensor such as that of Patent Document 2, the influence of temperature on the pressure measuring body can be corrected according to the temperature signal. By the way, while a part of the temperature measuring body is disposed so as to be exposed to the fluid to be measured, the pressure measuring body is disposed in the transmission body. Therefore, when the temperature of the fluid to be measured changes, the temperature change transmitted to the pressure measuring body occurs with a delay compared to the temperature change transmitted to the temperature measuring body, and there has been a case where the measured value of the pressure cannot be accurately obtained even when the above-described correction is performed.

[0011] The present invention has been made paying attention to such problems, and an object thereof is to provide a pressure temperature sensor capable of accurately measuring pressure.

Means for Solving the Problems

[0012] In order to solve the above problems, the pressure temperature sensor of the present invention a sensor body, a diaphragm that defines an accommodation space together with the sensor body, and a transmission medium filled in the accommodation space. A pressure measuring element and a temperature measuring element are arranged in the accommodation space. According to this, even if the temperature of the fluid to be sealed changes, for example, the pressure-temperature sensor can correct the pressure value measured by the pressure measuring element with the accurate temperature measured by the temperature measuring element. Thereby, the pressure-temperature sensor can accurately measure the pressure.

[0013] The pressure measuring element and the temperature measuring element may be arranged on the sensor body side. According to this, the measuring element is installed on the stationary side. Therefore, the physical change applied to the measuring element is small.

[0014] It includes a bonding wire electrically connected to the pressure measuring element or the temperature measuring element, and a buffer member that buffers the transmission medium may be arranged in the accommodation space between the diaphragm, the pressure measuring element, the temperature measuring element, and the bonding wire. According to this, even if a high pressure acts on the diaphragm from the fluid to be measured in a short time, the diaphragm does not deform significantly. Thereby, a large force does not act on the pressure measuring element, the temperature measuring element, and the bonding wire itself from the transmission medium. Therefore, the connection between the pressure measuring element, the temperature measuring element, each bonding wire and the bonding wire, and the connection between the temperature measuring element and the bonding wire are protected.

[0015] The buffer member may be arranged closer to the diaphragm than the pressure measuring element and the temperature measuring element. According to this, the space between the diaphragm and the buffer member becomes narrow. Thereby, even if a high pressure acts on the transmission medium in the space where the pressure measuring element and the temperature measuring element are accommodated from the fluid to be measured in a short time, a large pressure does not act.

[0016] The buffer member may be formed with a through hole. According to this, the through hole functions as an orifice. Therefore, the configuration of the buffer member is simple.

[0017] The buffer member may be formed such that the axis of the through hole is offset from the pressure measuring body and the temperature measuring body. According to this, it becomes difficult for the transmission body moving through the through hole to directly act on the pressure measuring body and the temperature measuring body. Thereby, the pressure measuring body and the temperature measuring body are protected.

[0018] The temperature measuring body may be a resistance temperature detector. According to this, the influence of the pressure acting on the temperature measuring body is reduced. Therefore, the pressure temperature sensor can measure temperature and pressure more simply and accurately.

[0019] The pressure measuring body and the temperature measuring body may be separate bodies. According to this, the separate pressure measuring body and temperature measuring body are arranged in a common accommodation space. Thereby, the pressure temperature sensor can adopt a measuring body suitable for each measured value and can have a structure with little influence from the other measured value.

[0020] The pressure temperature sensor may correct the measured value of the pressure measuring body and the measured value of the temperature measuring body with each other. According to this, the pressure temperature sensor can accurately measure pressure and temperature.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Best Mode for Carrying Out the Invention

[0022] The mode for carrying out the pressure-temperature sensor according to the present invention will be described below based on examples.

Example

[0023] The pressure-temperature sensor according to the example will be described with reference to FIGS. 1 to 4. Hereinafter, the upper, lower, left, and right sides as viewed from the front side of FIG. 2 will be described as the upper and lower sides of the pressure-temperature sensor. Specifically, the upper side of the paper surface where the connector 11 is arranged will be described as the upper side of the pressure-temperature sensor, and the lower side of the paper surface where the diaphragm cover 22 is arranged will be described as the lower side of the pressure-temperature sensor.

[0024] As shown in FIG. 1, the pressure-temperature sensor 1 of the present invention is configured to be able to detect the pressure of the measurement object and uses a battery (not shown) as a power source. Further, the pressure-temperature sensor 1 is fixed to an installation part such as a pipe, duct, or tank (not shown), and detects the pressure and temperature of the measurement object inside the installation part. The measurement object is a fluid to be measured such as a liquid or a gas.

[0025] As shown in FIG. 1, the pressure-temperature sensor 1 is mainly composed of a power supply unit 2 and a sensor unit 10. For example, by screwing the screw portion 2a formed at the lower end of the power supply unit 2 into the mounting port of a pipe (not shown), the pressure-temperature sensor 1 is fixed to the pipe (not shown) and used.

[0026] As shown in FIG. 2, the sensor unit 10 mainly includes, in order from the upper side, a connector 11, a substrate 12, a signal processing circuit 13, a plurality of electrode pins 14, a sensor body 15, a pressure measuring body 16, a temperature measuring body 17, a plurality of bonding wires 18, a spacer 19, an indoor cover 20 as a buffer member, a diaphragm 21, and a diaphragm cover 22.

[0027] Connector 11 is electrically connected to the power supply unit 2. The connector 11, the signal processing circuit 13, and the plurality of electrode pins 14 are electrically connected to the substrate 12. The sensor body 15 is formed of a metal material or a resin material.

[0028] The pressure measuring body 16 and the temperature measuring body 17 are disposed in the recess 150 of the sensor body 15. The plurality of bonding wires 18 are electrically connected to the electrode pin 14 and the pressure measuring body 16 or the electrode pin 14 and the temperature measuring body 17.

[0029] The spacer 19 is disposed in the recess 150. The diaphragm 21 is formed of a metal material or a resin material. The diaphragm cover 22 is formed of a metal material or a resin material. Further, the accommodation space R defined by the sensor body 15 and the diaphragm 21 is filled with silicone oil S as a transmission medium.

[0030] The sensor body 15 is formed in a bottomed cylindrical shape. The sensor body 15 is formed with a recess 150, a plurality of communication holes 151, and a communication path 152. The recess 150 is recessed axially upward from the lower end of the sensor body 15. The communication hole 151 penetrates axially from the outer diameter side end of the bottom surface 150a of the recess 150. The communication path 152 penetrates axially on the outer diameter side of one communication hole 151 of the bottom surface 150a.

[0031] The communication holes 151 are arranged substantially equally in the circumferential direction. Each communication hole 151 is sealed by a hermetic seal 23 with an electrode pin 14 inserted therethrough one by one.

[0032] In the recess 150, the upper end surfaces of the pressure measuring body 16 and the temperature measuring body 17 are adhered to the central portion of the bottom surface 150a by an adhesive.

[0033] The pressure measuring body 16 is a MEMS (Micro Electro Mechanical Systems) device. The sensing surface 16a, which is the lower surface of the pressure measuring body 16, is disposed opposite to the diaphragm 21. When the pressure acting on the sensing surface 16a changes, the resistance value of a strain gauge (not shown) changes. Utilizing this, the pressure measuring body 16 outputs a voltage corresponding to the pressure as a pressure signal, i.e., a measured value.

[0034] The temperature measuring body 17 has its sensing surface 17a, which is the lower surface thereof, disposed opposite to the diaphragm 21. When the temperature acting on the sensing surface 17a changes, the electrical resistance value changes. Utilizing this, the temperature measuring body 17 outputs a voltage corresponding to the temperature as a temperature signal, i.e., a measured value. Incidentally, the temperature measuring body 17 is preferably a platinum resistance thermometer, and may be other resistance thermometers other than the platinum resistance thermometer, such as a copper resistance thermometer or a nickel resistance thermometer.

[0035] Further, a spacer 19 formed in a cylindrical shape along a peripheral surface 150b substantially orthogonal to the bottom surface 150a is fitted into the concave portion 150. Also, the upper end surface of the spacer 19 is adhered to the outer diameter side end portion of the bottom surface 150a with an adhesive.

[0036] Referring to FIGS. 2 and 3, the spacer 19 is formed of aluminum. Also, the axial dimensions of the spacer 19 are formed to be substantially the same. The radial dimensions of the spacer 19 are formed to be substantially the same except that a thick-width portion 190 bulging toward the inner diameter side is partially formed. A communication passage 191 penetrating in the axial direction is formed in the thick-width portion 190. This communication passage 191 is formed in alignment with the communication passage 152 of the sensor body 15. A through-flow passage 24 communicating with the accommodation space R is formed by these communication passages 152 and 191.

[0037] Referring to FIG. 2, the through-flow passage 24 is a passage used when filling the accommodation space R with silicone oil S. After the silicone oil S is filled, an oil plug 25 is fitted to the upper end portion thereof and the through-flow passage 24 is sealed.

[0038] Further, an indoor cover 20 formed in a disk shape along the peripheral surface 150b is fitted into the concave portion 150. The upper end surface of the indoor cover 20 is adhered to the lower end surface of the spacer 19 with an adhesive.

[0039] Referring to FIGS. 2 and 4, the indoor cover 20 is formed of aluminum. The indoor cover 20 has a base portion 200 and a peripheral wall 201. The base portion 200 has a round flat plate shape. The peripheral wall 201 is annular and extends axially upward from the outer peripheral side end portion of the base portion 200. A through hole 202 penetrating axially is formed at the center of the base portion 200.

[0040] Further, the peripheral wall 201 of the indoor cover 20 is formed with substantially the same axial dimension. The radial dimension of the peripheral wall 201 is formed substantially the same except that a thin width portion 201a in which a part on the inner diameter side is recessed toward the outer diameter side is formed. This thin width portion 201a is formed in alignment with the thick width portion 190 of the spacer 19.

[0041] Further, a diaphragm 21 is fixed to the lower end of the sensor body 15 by welding or an adhesive. The accommodation space R formed between the concave portion 150 of the sensor body 15 and the diaphragm 21 is isolated from the fluid to be measured.

[0042] Regarding the accommodation space R in more detail, it is partitioned into a space R1 and a space R3. The space R1 is defined by the bottom surface 150a of the concave portion 150, the spacer 19, and the indoor cover 20. The space R3 is defined by the indoor cover 20, the peripheral surface 150b of the concave portion 150, and the diaphragm 21. The space R1 and the space R3 are communicated by the through hole 202 of the indoor cover 20.

[0043] Further, the space defined by the lower end surface of the thick width portion 190 of the spacer 19, the inner peripheral surface of the thin width portion 201a of the indoor cover 20, and the upper end surface of the base portion 200 inside the space R1 is called the space R2.

[0044] Also, referring to FIG. 2, the height dimension of the peripheral wall 201 of the indoor cover 20, more specifically, the dimension from the upper end surface of the base 200 to the upper end surface of the peripheral wall 201, is shorter than the thickness dimension of the base 200. As a result, the height dimension of the space R2 is also shorter than the thickness dimension of the base 200. Thus, the space R2 is a very narrow space within the space R1.

[0045] Further, at the lower end of the diaphragm 21, a diaphragm cover 22 formed in a dish shape is fixed by welding or an adhesive. Also, a plurality of communication passages 22a penetrating in the axial direction are formed at the bottom of the diaphragm cover 22.

[0046] Next, a method for outputting the measured pressure and temperature values by the pressure and temperature sensor 1 will be described. The pressure and temperature sensor 1 fixed to the attachment port of the pipe has the fluid to be measured flowing into the space between the diaphragm 21 and the diaphragm cover 22 through the communication passage 22a. The pressure and temperature are transmitted from this fluid to be measured to the silicone oil S through the diaphragm 21. Therefore, a voltage corresponding to the pressure of the silicone oil S can be obtained from the pressure measuring body 16. Also, a voltage corresponding to the temperature of the silicone oil S can be obtained from the temperature measuring body 17.

[0047] Each voltage obtained from the pressure measuring body 16 or the temperature measuring body 17 is an analog signal. Each analog signal is amplified by an amplification circuit (not shown) provided on the substrate 12, then input to the signal processing circuit 13, converted into a digital signal by the A / D conversion unit, and then corrected by the correction unit. Incidentally, the amplification circuit may or may not be provided in the pressure measuring body 16 and the temperature measuring body 17.

[0048] Digital signals are less affected by external factors such as noise than analog signals. From this, compared with a configuration in which A / D conversion is performed in the power supply unit 2, external devices, etc., the pressure and temperature sensor 1 of the present embodiment can output accurate measured pressure and temperature values to external devices.

[0049] The correction in the signal processing circuit 13 described above will be explained. In the correction unit, the digitized temperature data is compared with the reference data, and the digitized pressure data is corrected according to this difference. Thereby, the pressure temperature sensor 1 can accurately measure the pressure and the temperature.

[0050] Note that in the correction unit, the digitized pressure data may be compared with the reference data, and the digitized temperature data may be corrected according to this difference. Further, in the correction unit, the pressure data and the temperature data may be corrected mutually.

[0051] Furthermore, although the example in which the correction unit corrects the data after digital conversion has been described, it may correct the analog data and then convert it in the A / D converter unit.

[0052] As described above, the pressure temperature sensor 1 of the present embodiment can correct the value of the pressure measured by the pressure measuring body 16 at the accurate temperature measured by the temperature measuring body 17 even when the temperature of the sealed fluid changes, for example. Thereby, the pressure temperature sensor 1 can accurately measure the pressure.

[0053] Also, the pressure and the temperature act on the pressure measuring body 16 and the temperature measuring body 17 through the common silicone oil S. Thereby, the signal processing circuit 13 can correct the influence of the temperature on the pressure measuring body 16 without delay in time even when the temperature of the sealed fluid changes. Therefore, the pressure temperature sensor 1 can accurately measure the pressure.

[0054] Also, the pressure measuring body 16 and the temperature measuring body 17 are arranged on the sensor body 15 that does not operate due to pressure changes or temperature changes. Therefore, the physical changes applied to the pressure measuring body 16 and the temperature measuring body 17 are small.

[0055] Further, the pressure measuring element 16 and the temperature measuring element 17 are both arranged such that the sensing surfaces 16a and 17a face the diaphragm 21. In other words, the sensing surfaces 16a and 17a are arranged facing the same direction. Therefore, the time difference between the temperature acting on the temperature measuring element 17 and the temperature acting on the pressure measuring element 16 is smaller.

[0056] Also, when a shock wave or the like occurs in the fluid to be measured and a high pressure acts on the diaphragm 21 in a short time, the diaphragm 21 is recessed toward the space R3. At this time, the through hole 202 of the indoor cover 20 functions as an orifice that restricts the flow rate of the silicone oil S flowing from the space R3 to the space R1. As a result, the diaphragm 21 does not deform significantly. Therefore, no large force acts on the pressure measuring element 16, the temperature measuring element 17, and each bonding wire 18 from the silicone oil S.

[0057] In particular, since the pressure measuring element 16 is a MEMS with an outer dimension of around several millimeters and a thin portion less than 1 mm, it is difficult to have durability against external forces. Also, the connection points of each bonding wire 18 connected thereto are minute and may be peeled off by external forces. Therefore, in the pressure and temperature sensor 1 of the present embodiment, as described above, the connection between the pressure measuring element 16 and the bonding wire 18 and the connection between the temperature measuring element 17 and the bonding wire 18 are protected by the indoor cover 20. Incidentally, the bonding wire 18 is formed of a metal such as gold or aluminum, but other materials may be used as long as they can transfer the measurement signal.

[0058] Further, the indoor cover 20 is arranged closer to the diaphragm 21 than the pressure measuring element 16 and the temperature measuring element 17. Considering the difference between the diameter of the space R1 and the diameter of the space R3, the space R3 is narrower than the space R1. Therefore, even when a shock wave or the like occurs in the fluid to be measured and a high pressure acts on the diaphragm 21 in a short time, the amount of the silicone oil S moving from the space R3 to the space R1 is small. In other words, no large pressure acts on the silicone oil S in the space R1 where the pressure measuring element 16 and the temperature measuring element 17 are accommodated.

[0059] Also, as described above, the through-hole 202 serves as an orifice function. Therefore, the indoor cover 20 that can buffer the silicone oil S has a simple configuration.

[0060] Further, the through-hole 202 of the indoor cover 20 is arranged so that the axis P indicated by the dashed line passes between the pressure measuring body 16 and the temperature measuring body 17 disposed in the recess 150. Therefore, it is difficult for the silicone oil S moving through the through-hole 202 to directly act on the pressure measuring body 16 and the temperature measuring body 17. Thereby, the pressure measuring body 16 and the temperature measuring body 17 are protected.

[0061] In addition, each electrode pin 14 is arranged on the outer diameter side of the pressure measuring body 16 and the temperature measuring body 17. Therefore, the connection of each electrode pin 14 and each bonding wire 18, the connection of the pressure measuring body 16 and the bonding wire 18, and the connection of the temperature measuring body 17 and the bonding wire 18 are preferably protected.

[0062] Also, the plurality of electrode pins 14 are all arranged on the outer diameter side of the pressure measuring body 16 and the temperature measuring body 17. Therefore, compared with the configuration in which the electrode pins 14 are arranged between the pressure measuring body 16 and the temperature measuring body 17, the pressure measuring body 16 and the temperature measuring body 17 can be arranged closer to each other. Thereby, the time difference required until the temperature and pressure act on the pressure measuring body 16 or the temperature measuring body 17 is further reduced.

[0063] Also, the space R2 is a very narrow space within the space R1. Also, the space R2 is relatively separated from the through-hole 202 of the indoor cover 20. Thereby, it is difficult for the pressure and temperature of the fluid to be measured to affect the through-flow path 24 from the space R2.

[0064] Also, the through-flow path 24 communicates with the space R2 at the outer diameter end of the space R1. For example, compared with a configuration where the axis of the through-flow path 24 is located between the pressure measuring body 16 and the temperature measuring body 17, the pressure and temperature of the fluid to be measured are more easily transmitted to the space within the space R1 excluding the space R2. Thereby, the pressure-temperature sensor 1 can accurately measure the pressure and temperature of the fluid to be measured in a short time.

[0065] Also, the temperature measuring body 17 is a resistance temperature detector. From this, the influence of the pressure acting on the temperature measuring body 17 is reduced. Therefore, the pressure-temperature sensor 1 can measure temperature and pressure more simply and accurately.

[0066] Also, the separate pressure measuring body 16 and temperature measuring body 17 are arranged in a common accommodation space R filled with silicone oil S. Thereby, the pressure-temperature sensor 1 can adopt the measuring bodies 16 and 17 suitable for each measured value, and can have a structure with less influence received from the other measured value.

[0067] Also, it is difficult for foreign matters and the like to enter the space between the diaphragm cover 22 and the diaphragm 21 through its communication path 22a. Therefore, the diaphragm cover 22 can protect the diaphragm 21.

[0068] Also, the space R2 is composed of the thick-width portion 190 of the spacer 19 and the thin-width portion 201a of the indoor cover 20, which are separate from each other. The communication path 191 communicating with the space R2 is formed in the spacer 19. Thereby, compared with a mode in which the space R2 and the communication path 191 are integrally configured, the space R2 and the communication path 191 of the present embodiment can be simply configured.

[0069] In addition, the indoor cover 20 is formed of aluminum with high thermal conductivity. As a result, heat is easily transferred to the silicone oil S in the space R1. Therefore, the pressure temperature sensor 1 has good responsiveness in measuring pressure and temperature. Note that the indoor cover 20 may be formed of other metals or resins with high thermal conductivity and is not limited to aluminum.

[0070] In addition, both the spacer 19 and the indoor cover 20 are formed of aluminum. As a result, the influence of thermal expansion due to the temperature of the silicone oil S is substantially the same. Therefore, the spacer 19 and the indoor cover 20 are less likely to be damaged. Note that the spacer 19 and the indoor cover 20 are preferably formed of materials with the same coefficient of thermal expansion, but they may also be formed of materials with different coefficients of thermal expansion.

[0071] As described above, the embodiments of the present invention have been described with reference to the drawings. However, the specific configuration is not limited to these embodiments, and modifications and additions within the scope not departing from the gist of the present invention are also included in the present invention.

[0072] For example, in the above embodiment, the configuration has been described as measuring the absolute pressure to which atmospheric pressure does not act on the pressure measuring body. However, the present invention is not limited to this, and a configuration for measuring the gauge pressure by applying atmospheric pressure to the pressure measuring body may also be used.

[0073] In addition, the temperature measuring body has been described as being a resistance temperature detector. However, the present invention is not limited to this, and it may be a thermocouple, a thermistor, a resistance element, etc., and may be appropriately changed.

[0074] In addition, the pressure measuring body and the temperature measuring body have been described as being arranged on the bottom surface of the same recess. However, the present invention is not limited to this, and they may also be arranged on the peripheral surface of the recess.

[0075] In addition, the transmission medium has been described as being silicone oil. However, the present invention is not limited to this, and it may be water, air, oil, etc., and may be appropriately changed.

[0076] Also, although the spacer has been described as having a thick-width portion, it is not limited to this. The radial dimension of the peripheral wall, that is, the thickness dimension, may be relatively longer than the thickness dimension of the peripheral wall of the indoor cover and substantially the same over the circumferential direction. By adopting such a configuration, after fixing the spacer to the sensor body and forming the through-flow path, it becomes easy to form the through-flow path and the space communicating with the through-flow path.

Explanation of Signs

[0077] 1 Pressure-temperature sensor 10 Sensor unit 15 Sensor body 16 Pressure measurement body 16a Sensing surface 17 Temperature measurement body 17a Sensing surface 18 Bonding wire 20 Indoor cover 21 Diaphragm 202 Through-hole P Axis R Accommodation space S Silicon oil (transmitter)

Claims

1. A sensor body, a diaphragm that defines an accommodation space together with the sensor body, a transmission medium filled in the accommodation space, a diaphragm cover that sandwiches the diaphragm between the sensor body, comprising: in the accommodation space, a pressure measuring element and a temperature measuring element are arranged, further comprising a bonding wire electrically connected to the pressure measuring element or the temperature measuring element, a buffer member for buffering the transmission medium is arranged between the diaphragm, the pressure measuring element, the temperature measuring element and the bonding wire, a first through hole is formed at the radial center of the buffer member, the pressure measuring element and the temperature measuring element are arranged opposite to each other across the axis of the first through hole, a pressure and temperature sensor, wherein a second through hole that penetrates the diaphragm cover in the axial direction is formed at a position spaced from the radial center of the diaphragm cover.

2. The pressure and temperature sensor according to claim 1, wherein the pressure measuring element and the temperature measuring element are arranged on the sensor body side.

3. The pressure and temperature sensor according to claim 1 or 2, wherein the buffer member is arranged closer to the diaphragm than the pressure measuring element and the temperature measuring element.

4. The pressure and temperature sensor according to any one of claims 1 to 3, wherein the temperature measuring element is a resistance temperature detector.

5. The pressure and temperature sensor according to any one of claims 1 to 4, wherein the pressure measuring element and the temperature measuring element are separate bodies.

6. The pressure and temperature sensor according to any one of claims 1 to 5, wherein the measured value of the pressure measuring element and the measured value of the temperature measuring element are corrected with each other.

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