CN109154534B - Pressure detection device and biological information measurement system - Google Patents
Pressure detection device and biological information measurement system Download PDFInfo
- Publication number
- CN109154534B CN109154534B CN201780017225.XA CN201780017225A CN109154534B CN 109154534 B CN109154534 B CN 109154534B CN 201780017225 A CN201780017225 A CN 201780017225A CN 109154534 B CN109154534 B CN 109154534B
- Authority
- CN
- China
- Prior art keywords
- piezoelectric element
- pressure
- end wall
- hollow body
- chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/103—Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
- A61B5/11—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/103—Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
- A61B5/11—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb
- A61B5/113—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb occurring during breathing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/02—Measuring force or stress, in general by hydraulic or pneumatic means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Dentistry (AREA)
- Biophysics (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Physiology (AREA)
- Heart & Thoracic Surgery (AREA)
- Medical Informatics (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Measuring Fluid Pressure (AREA)
- Measuring And Recording Apparatus For Diagnosis (AREA)
- Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)
- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
Abstract
The pressure detection device includes: a piezoelectric element; a hollow body provided with an input chamber having the piezoelectric element as a part of a wall surface; and an introduction portion that is provided in the hollow body and communicates with the input chamber, the introduction portion introducing air into the input chamber in a direction inclined with respect to the piezoelectric element.
Description
Technical Field
The present invention relates to a pressure detection device and a biological information measurement system.
The present application claims priority based on patent application 2016-.
Background
Conventionally, as a biometric information measurement system, a configuration described in patent document 1 below is known. The biological information measurement system includes a pressure receiving portion and a pressure detection device. When the pressure receiving portion receives pressure, the pressure receiving portion sends air under pressure (send pressure) to the pressure detecting device.
Documents of the prior art
Patent document
Patent document 1: japanese patent laid-open publication No. 2005-110969
Problems to be solved by the invention
In a system for measuring minute pressure fluctuations (for example, respiratory rate, heart rate, and the like of an animal (human, livestock), etc.) generated in a measurement target body, such as a biological information measurement system, it is conceivable to adopt a structure including a piezoelectric element as a pressure detection device. In this configuration, the piezoelectric element receives the pressure of the air pressure-fed from the pressure receiving portion and converts the pressure into a voltage. At this time, the pressure receiving portion receives a pressure as large as the expected metering range, and when the pressure of the air pressure-fed from the pressure receiving portion to the pressure detection device is too high, the voltage converted by the piezoelectric element is also too high. As a result, the measurement accuracy of minute pressure fluctuations generated in the object to be measured may temporarily decrease.
Disclosure of Invention
The present invention has been made in view of the above problems, and an object thereof is to measure minute pressure fluctuations generated in a measurement target body with high accuracy.
Means for solving the problems
In order to solve the above problems, the present invention proposes the following means.
(1) The pressure detection device of the present invention includes a piezoelectric element; a hollow body provided with an input chamber having the piezoelectric element as a part of a wall surface; and an introduction portion that is provided in the hollow body and communicates with the input chamber, the introduction portion introducing air into the input chamber in a direction inclined with respect to the piezoelectric element.
The inclined direction includes a direction parallel to the piezoelectric element and does not include a perpendicular direction of the piezoelectric element.
In this case, the introduction portion introduces air into the input chamber toward the inclined direction. Therefore, for example, the pressure directly received by the piezoelectric element from the air introduced into the input chamber through the introduction portion can be suppressed to be smaller than in the case where the introduction portion introduces the air into the input chamber in the direction of the perpendicular line.
In addition, as described above, when the introduction portion introduces air into the input chamber in the direction of the perpendicular line, it is also possible to separate the piezoelectric element from the introduction portion in order to reduce the pressure directly received by the piezoelectric element from the air. In contrast, when the introduction portion introduces air into the input chamber in the inclined direction, the pressure can be suppressed to be small while the piezoelectric element is brought close to the introduction portion.
As described above, according to the pressure detection device, it is possible to measure minute pressure fluctuations generated in the measurement target body with high accuracy while achieving a small size.
(2) In the pressure detection device according to the above (1), a configuration may be adopted in which: the piezoelectric element is housed in the hollow body, and a reference chamber is formed in the hollow body on the opposite side of the input chamber with the piezoelectric element therebetween.
In this case, the piezoelectric element forms a reference chamber in the hollow body on the opposite side of the input chamber with the piezoelectric element sandwiched therebetween. Therefore, when air is introduced into the input chamber through the introduction portion, the piezoelectric element can be deformed based on the pressure difference between the input chamber and the reference chamber. This makes it possible to measure minute pressure fluctuations generated in the body to be measured with higher accuracy.
(3) In the pressure detection device described in the above (2), a configuration may be adopted in which: the hollow body includes a first end wall portion and a second end wall portion that are opposed to each other, and a peripheral wall portion that connects the first end wall portion and the second end wall portion, the piezoelectric element being inclined with respect to the first end wall portion.
In this case, the hollow body includes both end wall portions and a peripheral wall portion. This makes it possible to easily grip the hollow body or easily install the hollow body, and to improve the operability of the pressure detection device.
In addition, the piezoelectric element is inclined with respect to the first end wall portion. Therefore, for example, a larger piezoelectric element can be arranged in the hollow body than in the case where the piezoelectric element is arranged parallel to the first end wall portion. This makes it possible to easily improve the sensitivity of the piezoelectric element and to measure the minute pressure fluctuations generated in the object to be measured with higher accuracy.
(4) In the pressure detection device described in the above (3), a configuration may be adopted in which: the piezoelectric element is housed in a hollow body and connected to the piezoelectric element, the input chamber is formed between the piezoelectric element and the first end wall portion, and the substrate is disposed between the piezoelectric element and the second end wall portion in the hollow body and extends along the first end wall portion.
In this case, the piezoelectric element is inclined with respect to the first end wall portion. That is, in the piezoelectric element, one end wall of the pair of end portions located on both sides in the oblique direction is closer to the first end wall portion than the other end portion. This ensures a large space between the one end portion and the substrate. Here, the base plate 20 extends along the first end wall portion. Therefore, by disposing the projection (for example, an electronic component for arithmetic processing) disposed on the substrate in the wide space, the substrate can be brought close to the second end wall portion. Thus, although the substrate is disposed in the hollow body, the distance between the both end wall portions can be shortened, and the pressure detection device can be reliably downsized.
(5) In the pressure detection device described in the above (3) or (4), a configuration may be adopted in which: the introduction portion is provided in the peripheral wall portion.
In this case, the introduction portion is provided in the peripheral wall portion. Therefore, when the hollow body is gripped so as to sandwich the both end wall portions, or the first end wall portion or the second end wall portion is provided on the installation surface, it is possible to suppress the introduction portion from being disturbed. This can further improve the operability of the pressure detection device.
(6) In the pressure detection device according to any one of the above (2) to (5), a configuration may be adopted in which: further comprising a chamber member received within the hollow body and forming the reference chamber between the chamber member and the piezoelectric element.
In this case, since the reference chamber is formed between the piezoelectric element and the chamber member, the degree of freedom in designing the reference chamber can be increased relatively easily.
(7) In the pressure detection device according to any one of the above (2) to (6), a configuration may be adopted in which: further comprising a communication portion capable of communicating the inside of the reference chamber with the outside of the hollow body.
Depending on the environment in which the pressure detection device is used, the pressure (external pressure) outside the hollow body may fluctuate. For example, in the case of using a pressure detection device in a tightly closed room, slight fluctuation may be generated in external pressure due to closing of a door or the like. In this case, the input chamber may be affected by external pressure fluctuations through the introduction portion. In this case, when the reference chamber is not affected the same from the fluctuation of the external pressure, it may cause a decrease in the metering accuracy.
In the pressure detection device, the inside of the reference chamber and the outside of the hollow body can be communicated through the communication portion. Therefore, when the input chamber is affected by external pressure fluctuations, the communication portion communicates the inside of the reference chamber with the outside of the hollow body, and the reference chamber can be affected by the same through the communication portion. As a result, the in-phase component of the pressure fluctuation can be eliminated. On the other hand, in the case where the input chamber is not affected by the fluctuation of the external pressure, the communication between the inside of the reference chamber passing through the communication portion and the outside of the hollow body can be cut off so that the reference chamber is not affected. Thus, the minute pressure fluctuation generated in the object to be measured can be measured with high accuracy regardless of the influence on the input chamber caused by the external pressure fluctuation.
(8) In the pressure detection device according to any one of the above (1) to (7), a configuration may be adopted in which: the introduction portion introduces air into the input chamber toward a central portion of the piezoelectric element.
In this case, since the introduction portion introduces air into the input chamber toward the central portion of the piezoelectric element, minute pressure fluctuations generated in the body to be measured can be measured with high accuracy, and the measurement sensitivity can be ensured satisfactorily.
(9) The biometric information measuring system of the present invention includes: a pressure receiving portion that receives a pressure from a subject to be measured; and the pressure detection device according to any one of the above (1) to (8), wherein the pressure receiving portion sends air pressure to the introduction portion when the pressure receiving portion receives pressure.
In this case, since the biological information measuring system includes the pressure detecting means, minute pressure fluctuations generated in the measured body can be measured with high accuracy.
According to the present invention, minute pressure fluctuations generated in a measurement target can be measured with high accuracy.
Drawings
Fig. 1 is a sectional view of a part of a biometric information measurement system according to an embodiment of the present invention.
Fig. 2 is a plan view of a first divided body of a pressure detection device constituting the biometric information measuring system shown in fig. 1.
Fig. 3 is a perspective view showing a state in which a chamber member constituting the pressure detection device of the biological information measuring system shown in fig. 1 is turned upside down.
Detailed Description
The biometric information measurement system 10 according to an embodiment of the present invention will be described below with reference to fig. 1 to 3.
The biometric information measurement system 10 can be used for the purpose of nursing care and sleep management in the medical field and the nursing care field. The biometric information measurement system 10 can also be used in the field of livestock farming for the purpose of managing the heart rate, the number of ruminants, and physical activities of livestock.
The biological information measurement system 10 measures minute pressure fluctuations (for example, respiratory rate, heart rate, and the like) generated by a measurement target (for example, an animal such as a human or a livestock) as biological information. In addition, the biological information measuring system 10 can measure, as the biological information, pressure fluctuations (for example, physical activity or the like) having an amplitude larger than the minute pressure fluctuations, not only the minute pressure fluctuations.
For example, in the medical field and the nursing field, in the case where the biometric information measurement system 10 is used for a bed device (bed), the biometric information measurement system 10 can measure the respiratory rate, heart rate, physical activity, getting on the bed, and getting off the bed of a person in the bed. When the biometric information measurement system 10 is used in a toilet or a wheelchair, the biometric information measurement system 10 can measure the respiratory rate and the heart rate of a person sitting on the toilet or the wheelchair, and whether or not a person is sitting on the toilet or the wheelchair.
The biological information measuring system 10 is applied to the bed device, the toilet, and the wheelchair described above, and can measure biological information of a subject without restriction. The biometric information measurement system 10 detects a signal in a low frequency region (for example, a frequency of 0.1Hz to 200 Hz). The measurement result of the biometric information measurement system 10 is transmitted to an external information processing apparatus not shown. The information processing device displays the measurement result on a display unit, or stores the measurement result in a storage unit, for example.
The biometric information measurement system 10 includes a pressure receiving portion 11, a pressure detection device 12, and a connection pipe 13.
The pressure receiving portion 11 receives pressure from the object. In the present embodiment, the pressure receiving portion 11 is an elastically deformable hollow air cushion. When the pressure receiving portion 11 receives pressure, the pressure receiving portion 11 is compressed and deformed, and the air inside the pressure receiving portion 11 is pressure-fed to the pressure detection device 12. In this case, in the present embodiment, the air itself functions as a damper, and in fact, pressure fluctuations due to vibrations in the sound range (having a high frequency, for example, a frequency of about 300Hz to 4 kHz) are not transmitted to the pressure detection device 12.
The pressure detection device 12 detects the pressure received by the pressure receiving portion 11. The pressure detection device 12 includes a hollow body 15, a chamber member 16, a piezoelectric element 17, a communication portion 18, a blocking portion 19, a substrate 20, and an introduction portion 21.
The first end wall portion 22 and the second end wall portion 23 are opposed to each other. The both end wall portions 22 and 23 are formed in the same shape and the same size. The both end wall portions 22 and 23 have a rectangular shape in plan view. Hereinafter, the longitudinal direction of the rectangle is referred to as a longitudinal direction X, and the short-side direction is referred to as a short-side direction Y. The direction in which the first end wall 22 and the second end wall 23 face each other is referred to as a facing direction Z.
The peripheral wall 24 connects the end walls 22 and 23. The peripheral wall portion 24 is disposed between the both end wall portions 22, 23, and is formed in a rectangular frame shape in plan view. The peripheral wall portion 24 includes a pair of long-side wall portions 25 and a pair of short-side wall portions 26. Each of the long-side wall portions 25 extends in the longitudinal direction X. Each of the short-side wall portions 26 extends in the short-side direction Y. The end portions of the long-side wall portions 25 and the end portions of the short-side wall portions 26 are connected to each other to form corner portions of the peripheral wall portion 24.
The hollow body 15 is provided with a substrate base portion 27 and an element base portion 28.
The board base portion 27 includes four column portions 29. Each of the pillar portions 29 is disposed at a corner of the peripheral wall portion 24. Each pillar portion 29 extends from the first end wall portion 22 toward the second end wall portion 23. Each of the column parts 29 is formed in the same shape and the same size.
The element base portion 28 is raised from the first end wall portion 22 toward the second end wall portion 23. The dimension (height from the first end wall portion 22) of the element base portion 28 in the opposing direction Z gradually decreases from the first side X1 toward the second side X2 in the longitudinal direction X. The element base portion 28 is smaller than the pillar portion 29 in the opposing direction Z. In the element base portion 28, a surface opposite to the second end wall portion 23 is inclined with respect to the first end wall portion 22. The surface is an inclined surface inclined in the long side direction X.
The end portion of the first side X1 of the element base portion 28 is coupled to one of the short side wall portions 26 (hereinafter referred to as "coupled side wall portion 26 a"). The end portion of the second side X2 of the element base portion 28 is separated from the other short-side wall portion 26 in the longitudinal direction X. The end portion is formed in a curved shape protruding on the second side X2 in a plan view of the element base portion 28.
The element base portion 28 has ends in the short direction Y connected to a pair of long-side wall portions 25.
The element base portion 28 is raised from the first end wall portion 22 in a cylindrical shape and has an internal space. The inner peripheral surface of the element base portion 28 is formed into a circular shape (perfect circular shape) in a plan view of the element base portion 28. An annular step portion 30 is formed on an inner peripheral portion of the surface of the element base portion 28.
The hollow body 15 is divided into two parts in the opposite direction Z. The hollow body 15 is formed with an annular dividing portion 31 (dividing line). The dividing portion 31 divides the hollow body 15 into a first divided body 32 on the first end wall portion 22 side and a second divided body 33 on the second end wall portion 23 side. The divided portion 31 is located closer to the second end wall portion 23 than the substrate base portion 27 and the element base portion 28.
The cell member 16 is housed in the hollow body 15. The cell member 16 is formed in a flat, topped tubular shape that opens toward the first end wall portion 22. Cell member 16 is formed in a circular shape (perfect circular shape) in a plan view of cell member 16. The open end of the cell member 16 is disposed in the stepped portion 30 and fixed to the element base portion 28.
The piezoelectric element 17 converts the pressure into a voltage. The piezoelectric element 17 converts the pressure received by the pressure receiving surface 17a into a voltage. The piezoelectric element 17 is disposed in the hollow body 15, and in the present embodiment, is housed in the hollow body 15. The piezoelectric element 17 is formed in a circular thin plate shape (film shape) with a surface facing the first end wall portion 22, and in the present embodiment, the surface is a pressure receiving surface 17 a. The diameter of the piezoelectric element 17 is, for example, about 15 mm.
The piezoelectric element 17 is mounted on the chamber member 16. The piezoelectric element 17 is disposed in the chamber member 16. In the present embodiment, the outer peripheral edge of the piezoelectric element 17 is fixed to the inner peripheral edge of the opening end of the chamber member 16 over the entire circumference. The piezoelectric element 17 is inclined with respect to the first end wall portion 22. The piezoelectric element 17 extends in parallel along the surface of the element base portion 28, and is inclined with respect to the longitudinal direction X.
The piezoelectric element 17 closes the internal space of the element base portion 28 from the second end wall portion 23 side. The pressure receiving surface 17a faces the first end wall portion 22 through the inside of the element base portion 28.
The piezoelectric element 17 forms, inside the hollow body 15, an input chamber 35 and a reference chamber 36. The piezoelectric element 17 divides the air chamber 34 into an input chamber 35 and a reference chamber 36.
The input chamber 35 and the reference chamber 36 are sealed, respectively. In the input chamber 35, communication toward the outside is blocked by the pressure receiving surface 17a of the piezoelectric element 17 and the element base portion 28. In the reference chamber 36, communication toward the outside is blocked by the outer peripheral edge of the piezoelectric element 17 and the inner peripheral edge of the chamber member 16.
The input chamber 35 has the piezoelectric element 17 (pressure receiving surface 17a) as a part of the wall surface. The input chamber 35 is configured such that the inside of the element base portion 28 is closed by the piezoelectric element 17. The input chamber 35 is formed between the piezoelectric element 17 and the first end wall portion 22.
The reference chamber 36 is provided in the hollow body 15 on the opposite side of the input chamber 35 sandwiching the piezoelectric element 17. A reference chamber 36 is formed between the piezoelectric element 17 and the chamber member 16.
The substrate 20 is housed in the hollow body 15. The piezoelectric element 17 is connected to the substrate 20. In the present embodiment, a lead wire, not shown, extending from the piezoelectric element 17 is connected to the substrate 20. The substrate 20 is disposed between the piezoelectric element 17 and the second end wall portion 23 in the hollow body 15. The base plate 20 extends along a first endwall portion 22. The base plate 20 is parallel to the first end wall portion 22 and the second end wall portion 23.
The substrate 20 is provided with a projection 37. In the present embodiment, the substrate 20 is a circuit board, and the projections 37 are, for example, electronic components for arithmetic processing. The protrusion 37 protrudes from the base plate 20 toward the first end wall portion 22 side. A plurality of projections 37 are provided along the longitudinal direction X. The amount of projection of the plurality of projections 37 increases from the first side X1 toward the second side X2.
The substrate 20 (circuit board) forms an arithmetic processing unit 38. The arithmetic processing unit 38 converts the voltage from the piezoelectric element 17 into an electric signal, and sends the electric signal as a measurement result to the information processing apparatus. The substrate 20 is connected to the information processing apparatus via a cable not shown. The cable passes through a part of the circumferential direction of the divided portion 31 and extends from the inside to the outside of the hollow body 15.
The arithmetic processing unit 38 may filter noise in the voltage converted by the piezoelectric element 17. The noise is a voltage based on vibration of a certain frequency region input to the pressure receiving portion 11. The predetermined frequency range may be a high frequency range of 300Hz or more.
Such noise may be generated by rubbing the surface of the pressure receiving portion 11, for example.
In addition, instead of the above-described circuit board having the arithmetic processing unit 38, a connector board not having the arithmetic processing unit 38 may be used as the board 20. In this case, a circuit board (arithmetic processing unit 38) may be separately provided outside, and the piezoelectric element 17 may be connected to an external circuit board via a connector substrate. At this time, the connector substrate and the circuit board can be connected via the shield wire. In this case, the protrusion 37 is, for example, a connector or the like.
The communication portion 18 can communicate the inside of the reference chamber 36 with the outside of the hollow body 15. The communication portion 18 can open the sealed reference chamber 36 to the outside. The communication portion 18 includes a first communication portion 39, a second communication portion 40, and a third communication portion not shown.
The first communicating portion 39 is provided in the chamber member 16. The first communicating portion 39 is a through hole that penetrates the chamber member 16. The first communicating portion 39 is disposed in the center of the top wall of the chamber member 16.
The second communicating portion 40 is provided inside the hollow body 15. The second communicating portion 40 is formed by a space between the element base portion 28, the first end wall portion 22, the peripheral wall portion 24, and the second end wall portion 23. The substrate 20 is disposed in the second communicating portion 40.
The third communicating portion is provided between the first and second divided bodies 32 and 33. The third communicating portion is provided in a portion of the divided portion 31 through which the cable passes. Said third communication is formed by a gap provided between the hollow body 15 and said cable.
The blocking portion 19 blocks communication between the inside of the reference chamber 36 of the communicating portion 18 and the outside of the hollow body 15. The blocking portion 19 closes the first communicating portion 39. The blocking portion 19 is a film adhered to the cell member 16. The blocking portion 19 adheres to the chamber member 16 from the opposite side (the second communicating portion 40 side) of the reference chamber 36.
The introduction portion 21 is provided in the hollow body 15 and communicates with the inside of the inlet chamber 35. The introduction portion 21 can open the sealed input chamber 35 to the outside. The introduction portion 21 introduces air into the input chamber 35 in a direction inclined with respect to the piezoelectric element 17 (pressure receiving surface 17 a). In the oblique direction, the direction parallel to the piezoelectric element 17 (pressure receiving surface 17a) is included, and the direction of the perpendicular line P of the piezoelectric element 17 (pressure receiving surface 17a) is not included. In the illustrated example, the introduction portion 21 introduces air into the input chamber 35 in the inclined direction (except for the direction parallel to the piezoelectric element 17).
The introduction portion 21 is provided in the peripheral wall portion 24. The introduction portion 21 penetrates the hollow body 15. The introduction portion 21 introduces air into the input chamber 35 toward the center portion of the piezoelectric element 17. The introduction portion 21 is formed of a member separate from the hollow body 15. The introduction portion 21 is a pipe body.
The axis O of the introduction portion 21 extends in the longitudinal direction X, and in the illustrated example, extends parallel to the first end wall portion 22. The axis O passes through the center of the pressure receiving surface 17a and is inclined with respect to the pressure receiving surface 17a and the perpendicular line P. In a cross-sectional view taken along both the longitudinal direction X and the opposing direction Z, the inclination angle θ between the axis O and the pressure receiving surface 17a is, for example, 45 ° or less. The inclination angle θ is greater than 0 ° and 45 ° or less, for example, 10 ° or more and 20 ° or less.
The introduction portion 21 integrally penetrates the coupling side wall portion 26a and the end portion of the first side X1 of the element base portion 28. The end of the first side X1 of the introduction portion 21 protrudes from the hollow body 15 toward the first side X1. The end of the second side X2 of the introduction portion 21 does not protrude into the input chamber 35. The end face of the second side X2 of the introduction portion 21 is arranged at the same position as the inner peripheral surface (inner surface of the input chamber 35) of the element base portion 28 in the longitudinal direction X.
The connection pipe 13 connects the pressure receiving portion 11 and the introduction portion 21. The connection pipe 13 guides the air from the pressure receiving portion 11 to the introduction portion 21. The inner diameter of the introduction portion 21 and the inner diameter of the connection pipe 13 are each 2mm or less, for example.
In the biological information measuring system 10, when the pressure receiving portion 11 receives pressure, the pressure receiving portion 11 sends air under pressure (send pressure) to the introduction portion 21. In the present embodiment, the pressure receiving portion 11 is not deformed by fluctuations in the pressure (external pressure) outside the hollow body 15, and the pressure receiving portion 11 is not substantially affected by the fluctuations in the external pressure. Thus, the input chamber 35 is also virtually unaffected by fluctuations in external pressure.
As described above, according to the pressure detection device 12 and the biological information measuring system 10 of the present embodiment, the introduction unit 21 introduces air into the input chamber 35 in the inclined direction. Therefore, for example, the pressure directly received by the piezoelectric element 17 from the air introduced into the input chamber 35 through the introduction portion 21 can be suppressed to be smaller than in the case where the introduction portion 21 introduces air into the input chamber 35 in the direction of the perpendicular line P.
In addition, as described above, when the introduction portion 21 introduces air into the input chamber 35 in the direction of the perpendicular line P, it is also conceivable to separate the piezoelectric element 17 from the introduction portion 21 in order to reduce the pressure directly received by the piezoelectric element 17 from the air. In contrast, when the introduction portion 21 introduces air into the input chamber 35 in the above-described oblique direction, the pressure can be suppressed to be small while the piezoelectric element 17 and the introduction portion 21 are brought close to each other.
As described above, according to the pressure detection device 12, it is possible to measure minute pressure fluctuations generated in the measurement target body with high accuracy while achieving a small size.
Further, since the introduction portion 21 introduces air into the input chamber 35 toward the central portion of the piezoelectric element 17, minute pressure fluctuations generated in the body to be measured can be measured with high accuracy, and the measurement sensitivity can be ensured satisfactorily.
In the piezoelectric element 17, a reference chamber 36 is formed in the hollow body 15 on the opposite side of the input chamber 35 with the piezoelectric element 17 therebetween. Therefore, when air is introduced into the input chamber 35 through the introduction portion 21, the piezoelectric element 17 can be deformed based on the pressure difference between the input chamber 35 and the reference chamber 36. This makes it possible to measure minute pressure fluctuations generated in the body to be measured with higher accuracy.
Further, since the reference chamber 36 is formed between the piezoelectric element 17 and the chamber member 16, the degree of freedom in designing the reference chamber 36 can be increased relatively easily.
The hollow body 15 includes two end wall portions 22 and 23 and a peripheral wall portion 24. This makes it possible to easily grip the hollow body 15, to easily provide the hollow body 15, and to improve the operability of the pressure detection device 12.
In addition, the piezoelectric element 17 is inclined with respect to the first end wall portion 22. Therefore, for example, the piezoelectric element 17 can be arranged in the hollow body 15 in a larger size than in the case where the piezoelectric element 17 is arranged parallel to the first end wall portion 22. This makes it possible to easily improve the sensitivity of the piezoelectric element 17 and to measure the minute pressure fluctuations generated in the object to be measured with higher accuracy
In addition, the piezoelectric element 17 is inclined with respect to the first end wall portion 22. In the present embodiment, the end of the second side X2 of the piezoelectric element 17 is closer to the first end wall portion 22 than the end of the first side X1. This ensures a large space between the end of the second side X2 of the piezoelectric element 17 and the substrate 20. Here, the base plate 20 extends along the first end wall portion 22. Therefore, by disposing the protrusion 37 disposed on the substrate 20 in the wide space, the substrate 20 and the second end wall portion 23 can be brought close to each other. Thus, although the substrate 20 is disposed in the hollow body 15, the distance between the both end wall portions 22 and 23 can be shortened, and the pressure detection device 12 can be reliably downsized.
Further, since the introduction portion 21 is provided in the peripheral wall portion 24, when the hollow body 15 is gripped so as to sandwich the both end wall portions 22 and 23, or the first end wall portion 22 or the second end wall portion 23 is provided on the installation surface, it is possible to suppress the introduction portion 21 from being disturbed. This can further improve the operability of the pressure detection device 12.
However, depending on the environment in which the pressure detection device 12 is used, the pressure (external pressure) outside the hollow body 15 may fluctuate. For example, in the case where the pressure detection device 12 is used in a tightly closed room, slight fluctuation may occur in external pressure due to closing of a door or the like. At this time, the input chamber 35 may be affected by external pressure fluctuations through the introduction portion 21. In this case, when the reference chamber 36 is not affected the same from the fluctuation of the external pressure, it may cause a decrease in the metering accuracy.
In the pressure detection device 12, the inside of the reference chamber 36 and the outside of the hollow body 15 can communicate with each other through the communication portion 18. Therefore, unlike the present embodiment, when the input chamber 35 (pressure receiving portion 11) is affected by external pressure fluctuations, the communication portion 18 communicates the inside of the reference chamber 36 with the outside of the hollow body 15 except for the blocking portion 19, and the communication portion 18 can also affect the reference chamber 36. As a result, the in-phase component of the pressure fluctuation can be eliminated. On the other hand, as in the present embodiment, when the input chamber 35 (pressure receiving portion 11) is not affected by external pressure fluctuations, the communication between the inside of the reference chamber 36 passing through the communication portion 18 and the outside of the hollow body 15 can be blocked by the structure such as the blocking portion 19, so that the reference chamber 36 is not affected by the above. Thus, the minute pressure fluctuation generated in the object to be measured can be accurately measured even if the external pressure fluctuation has an influence on the input chamber 35.
The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the technical spirit of the present invention.
The pressure receiving portion 11 may have a structure different from that of the air cushion. For example, the pressure receiving portion 11 may be configured to include a vibrating plate as in a portion of a stethoscope that directly contacts the skin.
The introduction portion 21 may introduce air into the input chamber 35 without going toward the center of the piezoelectric element 17. The introduction portion 21 may introduce air into the input chamber 35 toward the outer periphery of the piezoelectric element 17, or may not introduce air toward the piezoelectric element 17. The axis O may or may not pass through the outer peripheral edge of the pressure receiving surface 17 a.
The introduction portion 21 may not be a pipe. For example, the introduction portion 21 may be a passage formed in the hollow body 15.
The introduction portion 21 may be provided in the first end wall 22 and the second end wall 23. The substrate 20 may not be housed in the hollow body 15.
The blocking portion 19 and the communicating portion 18 may be omitted.
In addition, the components in the above embodiments may be replaced with well-known components as appropriate, and the above modifications may be combined as appropriate, without departing from the scope of the present invention.
Industrial applicability of the invention
According to the present invention, since minute pressure fluctuations generated in a measurement target can be measured with high accuracy, the present invention has high industrial applicability.
Description of the symbols
10 biometric information metering system
11 pressure receiving part
12 pressure detection device
15 hollow body
16 cell member
17 piezoelectric element
18 connecting part
20 base plate
21 introduction part
22 first end wall portion
23 second endwall portion
24 peripheral wall part
35 input chamber
36 reference chamber
Claims (9)
1. A pressure detection device, comprising:
a piezoelectric element;
a hollow body provided with an input chamber having the piezoelectric element as a part of a wall surface and a sealed reference chamber provided on an opposite side of the input chamber with the piezoelectric element interposed therebetween; and
an introduction portion provided in the hollow body and communicating with the input chamber, the introduction portion introducing air into the input chamber in a direction inclined with respect to the piezoelectric element.
2. The pressure detecting device according to claim 1,
a through hole is provided in a chamber member constituting the reference chamber.
3. The pressure detecting device according to claim 1 or 2,
the hollow body includes a first end wall portion and a second end wall portion opposed to each other, and a peripheral wall portion joining the first end wall portion and the second end wall portion,
the piezoelectric element is inclined with respect to the first end wall portion.
4. The pressure detecting device according to claim 3,
further comprising a substrate housed in the hollow body and connected to the piezoelectric element,
the input chamber is formed between the piezoelectric element and the first end wall portion,
the substrate is disposed between the piezoelectric element and the second end wall portion in the hollow body, and extends along the first end wall portion.
5. The pressure detecting device according to claim 3,
the introduction portion is provided in the peripheral wall portion.
6. The pressure detecting device according to claim 2,
the chamber member is housed within the hollow body, and the reference chamber is formed between the chamber member and the piezoelectric element.
7. The pressure detecting device according to claim 1 or 2,
further comprising a communication portion capable of communicating the inside of the reference chamber with the outside of the hollow body.
8. The pressure detecting device according to claim 1 or 2,
the introduction portion introduces air into the input chamber toward a central portion of the piezoelectric element.
9. A biometric information measurement system, comprising:
a pressure receiving portion that receives a pressure from a subject to be measured; and
the pressure detecting device according to any one of the preceding claims 1 to 8,
when the pressure receiving portion receives pressure, the pressure receiving portion sends air pressure to the introduction portion.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016111911A JP6612682B2 (en) | 2016-06-03 | 2016-06-03 | Pressure detecting device and biological information measuring system |
| JP2016-111911 | 2016-06-03 | ||
| PCT/JP2017/020430 WO2017209239A1 (en) | 2016-06-03 | 2017-06-01 | Pressure detection device and biological information measuring system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109154534A CN109154534A (en) | 2019-01-04 |
| CN109154534B true CN109154534B (en) | 2020-07-14 |
Family
ID=60478657
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201780017225.XA Active CN109154534B (en) | 2016-06-03 | 2017-06-01 | Pressure detection device and biological information measurement system |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP6612682B2 (en) |
| CN (1) | CN109154534B (en) |
| WO (1) | WO2017209239A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022138609A1 (en) * | 2020-12-25 | 2022-06-30 | 株式会社リキッド・デザイン・システムズ | Pressure sensor, and biometric information measuring device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62121530U (en) * | 1986-01-23 | 1987-08-01 | ||
| JPH09229801A (en) * | 1996-02-26 | 1997-09-05 | Matsushita Electric Works Ltd | Semiconductor pressure sensor |
| JPH10332512A (en) * | 1997-06-03 | 1998-12-18 | Osaka Gas Co Ltd | Differential pressure sensor and instrument and method for measuring flow rate |
| JP2005110969A (en) * | 2003-10-08 | 2005-04-28 | Yamatake Corp | Biological information measuring device |
| CN104458112A (en) * | 2013-09-18 | 2015-03-25 | 阿尔卑斯电气株式会社 | Pressure detection device and intake pressure measurement apparatus using the same |
| CN105190272A (en) * | 2013-02-28 | 2015-12-23 | Mks仪器公司 | Pressure sensor with real time health monitoring and compensation |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4389375B2 (en) * | 2000-01-18 | 2009-12-24 | 株式会社デンソー | Pressure sensor |
| JP4141219B2 (en) * | 2002-09-27 | 2008-08-27 | 株式会社タニタ | Biological signal detection device and sleep measurement device using the same |
| US8672853B2 (en) * | 2010-06-15 | 2014-03-18 | Bam Labs, Inc. | Pressure sensor for monitoring a subject and pressure sensor with inflatable bladder |
-
2016
- 2016-06-03 JP JP2016111911A patent/JP6612682B2/en active Active
-
2017
- 2017-06-01 WO PCT/JP2017/020430 patent/WO2017209239A1/en active Application Filing
- 2017-06-01 CN CN201780017225.XA patent/CN109154534B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62121530U (en) * | 1986-01-23 | 1987-08-01 | ||
| JPH09229801A (en) * | 1996-02-26 | 1997-09-05 | Matsushita Electric Works Ltd | Semiconductor pressure sensor |
| JPH10332512A (en) * | 1997-06-03 | 1998-12-18 | Osaka Gas Co Ltd | Differential pressure sensor and instrument and method for measuring flow rate |
| JP2005110969A (en) * | 2003-10-08 | 2005-04-28 | Yamatake Corp | Biological information measuring device |
| CN105190272A (en) * | 2013-02-28 | 2015-12-23 | Mks仪器公司 | Pressure sensor with real time health monitoring and compensation |
| CN104458112A (en) * | 2013-09-18 | 2015-03-25 | 阿尔卑斯电气株式会社 | Pressure detection device and intake pressure measurement apparatus using the same |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109154534A (en) | 2019-01-04 |
| JP2017219341A (en) | 2017-12-14 |
| JP6612682B2 (en) | 2019-11-27 |
| WO2017209239A1 (en) | 2017-12-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20180177482A1 (en) | Biological sound measurement apparatus | |
| US11857760B2 (en) | Fluid sensor | |
| WO2017187710A1 (en) | Vibration waveform sensor and pulse wave detector | |
| EP2503304A1 (en) | Ultrasonic flowmeter | |
| US7714482B2 (en) | Ultrasonic sensor | |
| US8483399B2 (en) | Condenser microphone, microphone unit, and blood pressure gauge | |
| US20200029907A1 (en) | Seating sensor, seat, and waveform analysis apparatus | |
| EP1519165A2 (en) | Piezoelectric vibration sensor | |
| CN109154534B (en) | Pressure detection device and biological information measurement system | |
| US11045093B2 (en) | Sensor unit | |
| US11311238B2 (en) | Attachable sensing pod comprising a piezoelectric unit | |
| US5954669A (en) | Hand-held hearing screener apparatus | |
| US20230019623A1 (en) | Wheeze detection device | |
| JP5103882B2 (en) | Heart rate detector | |
| WO2019159502A1 (en) | Fluid control device | |
| US20210268256A1 (en) | Connection member, injection device and pump casing equipped with connection member, and liquid verification method using connection member | |
| JP6721467B2 (en) | Microphone | |
| JP7431293B2 (en) | Vibrometers, electronics, and electronic systems | |
| US20210330282A1 (en) | Biological sound measurement device | |
| JPWO2019159502A1 (en) | Fluid control device | |
| US20210204812A1 (en) | Biosensor | |
| CN116724216A (en) | Gyroscope-type vibrating meter, electronic equipment and electronic system | |
| WO2019163515A1 (en) | Biological sensor | |
| JP2024027704A (en) | Ultrasonic device | |
| KR20020080830A (en) | Sensor structure for portable pulsimeter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |