JP4988034B2 - Pulse detection device and ultrasonic diagnostic device - Google Patents

Description

  The present invention relates to a pulse detection apparatus using a piezoelectric element as a detection element and an ultrasonic diagnostic apparatus using the piezoelectric element.

  The vital pulse contains important information that can be applied to the diagnosis of disease. Therefore, in recent years, a system in which a portable pulse detection device is attached to the patient's arm, the patient's pulse detection data transmitted from the portable pulse detection device is received, and the patient's state is grasped is a hospital or the like. It is being considered in medical facilities. It is effective to use a piezoelectric element in order to reduce the size and weight of the pulse detection device, and development of a pulse detection device using a piezoelectric element is being promoted in consideration of application to the above-described system. Similarly, an ultrasonic diagnostic apparatus that obtains information on a living body or an object using ultrasonic waves is well known. This ultrasonic diagnostic apparatus irradiates (transmits) ultrasonic waves to a diagnostic part of a subject or a diagnostic object, detects a reflected wave reflected at the diagnostic part, and acquires information about the diagnostic part based on the detection result To do.

  A conventional pulse detection device 100 using a piezoelectric element is shown in FIG. As shown in the figure, the pulse detecting device 100 is obtained by embedding and fixing two piezoelectric elements 110 and 120 in a resin (or gel) 130. Here, metallic electrodes are formed on both surfaces of the piezoelectric elements 110 and 120 in the thickness direction (not shown). In addition, a drive voltage application probe (terminal, lead wire, etc.) is connected to both electrodes of the piezoelectric element 110, and a voltage signal output probe (terminal, lead wire, etc.) is connected to both electrodes of the piezoelectric element 120. Are connected (not shown).

  Further, for example, in an ultrasonic pulse wave detection device, an ultrasonic wave is transmitted toward the subject's radial artery, and a pulse wave waveform and a pulse rate are acquired from changes in the amplitude and frequency of the reflected wave.

  The patient's pulse is detected using this pulse detection device 100 at the time of medical examination. Specifically, when a driving voltage is applied to both electrodes of the piezoelectric element 110, the piezoelectric element 110 is excited to generate an ultrasonic wave, and the ultrasonic wave is transmitted into the living body via the resin 130. The ultrasonic wave transmitted into the living body is reflected by the blood flow of the living body, and the reflected ultrasonic wave is received by the piezoelectric element 120 through the resin 130. At this time, a frequency change occurs in the ultrasonic wave transmitted by the piezoelectric element 110 and the ultrasonic wave received by the piezoelectric element 120 due to the Doppler effect of blood flow. Further, since the blood flow velocity changes in synchronization with the pulse, the biological pulse is detected by the frequency change of the ultrasonic wave.

  By the way, in the above-described pulse detection device using a piezoelectric element, the ultrasonic transmission piezoelectric element 110 and the ultrasonic reception piezoelectric element 120 are accurately arranged in order to improve the ultrasonic reception sensitivity. There is a need to.

  However, since the pulse detecting device 100 described above is manufactured by pouring the resin 130 after the two piezoelectric elements 110 and 120 are arranged at predetermined positions, the arrangement position and the arrangement angle of these piezoelectric elements are different when the resin is poured. There has been a problem that there is a possibility of displacement and it is difficult to accurately arrange the piezoelectric elements.

  Therefore, the conventional pulse detection device 100 may have quality variations.

  In view of the above, an object of the present invention is to provide a pulse detecting device in which quality variation is less likely to occur by accurately arranging a piezoelectric element for ultrasonic transmission and a piezoelectric element for ultrasonic reception, and a method for manufacturing the same. And Another object of the present invention is to improve pulse detection sensitivity in the pulse detection device.

  In general, in a pulse detection device using a piezoelectric element, it is necessary to accurately arrange an ultrasonic transmission piezoelectric element and an ultrasonic reception piezoelectric element in order to improve ultrasonic reception sensitivity. In addition, if the ultrasonic wave is transmitted through the substrate and directly received by the receiving piezoelectric element, it causes noise, and the intensity of the transmitted wave and the received wave to the bloodstream, which is originally necessary for measuring the pulse, is increased. As a result, the pulse detection sensitivity decreases. Therefore, in order to improve the pulse detection sensitivity, it is necessary to have a structure in which the ultrasonic waves are not easily received by the receiving piezoelectric element through the substrate. Further, the thicker the resin 130, the lower the intensity of the ultrasonic wave transmitted to the bloodstream in the living body.

However, since the pulse detecting device 100 described above is manufactured by pouring the resin 130 after arranging the two piezoelectric elements 110 and 120 at predetermined positions, there are the following problems.
(1) When the resin is poured, there is a possibility that the arrangement position and the arrangement angle of these piezoelectric elements are shifted, and it is difficult to arrange the piezoelectric elements with high accuracy, and there may be variations in quality.
(2) The pulse detection sensitivity is limited because the ultrasonic wave is easily received by the receiving piezoelectric element through the resin.
(3) Since it is difficult to manufacture the resin 130 with a small thickness, the pulse detection sensitivity is limited.

  In view of this, the present invention provides a pulse detecting device in which quality variation is unlikely to occur, and a pulse having a structure for improving sensitivity, by accurately arranging a piezoelectric element for ultrasonic transmission and a piezoelectric element for ultrasonic reception. An object is to provide a detection device.

  Also, the ultrasonic diagnostic apparatus has the same problems as the pulse detection apparatus described above. Therefore, the present invention provides an ultrasonic diagnostic apparatus in which quality variation is unlikely to occur by accurately arranging a piezoelectric element for ultrasonic transmission and a piezoelectric element for ultrasonic reception, and a structure for improving sensitivity and An object of the present invention is to provide an ultrasonic diagnostic apparatus of the manufacturing method.

  In order to solve the above-described problems, a pulse detecting device according to the present invention includes a transmitting piezoelectric element (a piezoelectric element that transmits ultrasonic waves into a living body in accordance with an input drive signal) and a receiving piezoelectric element (an ultrasonic wave is transmitted from At least one of the piezoelectric elements that receives the reflected wave reflected by the blood flow is fixed on the substrate by a power feeding unit that applies a drive signal to the piezoelectric elements. According to this configuration, since at least one of the transmitting piezoelectric element and the receiving piezoelectric element is mounted and fixed on the substrate, these piezoelectric elements can be accurately arranged as designed.

  Therefore, according to the configuration of the present invention, it is possible to provide a pulse detector that is unlikely to cause variations in quality. In addition, since the piezoelectric element and the substrate are fixed not by the entire surface of the substrate but by the power feeding unit, the ultrasonic wave does not easily propagate to the substrate, noise can be reduced, and sensitivity can be improved.

  Furthermore, a gap was formed between the substrate and the piezoelectric element. According to such a configuration, it is difficult for ultrasonic waves to be transmitted from the transmitting piezoelectric element to the substrate, and the possibility that the ultrasonic waves are transmitted through the substrate and directly received by the receiving piezoelectric element is reduced, thereby reducing noise. And the sensitivity can be improved.

  Furthermore, by using a structure in which the power supply part protrudes from the piezoelectric element, a structure in which the piezoelectric element protrudes from the power supply part, or a porous substrate, the ultrasonic wave is further transmitted through the substrate for reception. Since the structure is unlikely to be directly received by the piezoelectric element, noise can be reduced and sensitivity can be improved.

  Further, a groove is provided in a part of the substrate, and the transmitting piezoelectric element and the receiving piezoelectric element are arranged with the groove interposed therebetween. According to this configuration, since the ultrasonic wave generated by the transmitting piezoelectric element is reflected and attenuated by the groove between the transmitting piezoelectric element and the receiving piezoelectric element on the substrate, the ultrasonic wave is transmitted through the substrate. The possibility of being directly received by the receiving piezoelectric element is further reduced. For this reason, the sensitivity of the pulse detector can be improved.

  Alternatively, the substrate may be divided, the transmitting piezoelectric element may be disposed on one of the divided substrates, and the receiving piezoelectric element may be disposed on the other substrate. In this case, the ultrasonic wave generated by the transmitting piezoelectric element is more difficult to be transmitted directly to the receiving piezoelectric element. Therefore, the sensitivity of the pulse detector can be improved.

  In addition, by providing a resin layer on the piezoelectric element installation surface of the substrate, ultrasonic waves are effectively transmitted into the living body. In addition, since the piezoelectric element is arranged on the substrate, the resin layer can be easily arranged with a constant thickness. The resin layer is divided between the transmitting piezoelectric element and the receiving piezoelectric element, and the ultrasonic wave generated by the transmitting piezoelectric element is not easily transmitted directly to the receiving piezoelectric element through the resin layer. did.

  Further, by providing the support substrate, the strength and handleability of the pulse detection device against an external impact are improved.

  Moreover, it is good also as a structure provided with the display part which displays the pulse detected by the detection part. By adopting a configuration including a belt for mounting the pulse detection device on the wrist, the living body can easily carry the pulse detection device.

  In order to solve the above problems, a pulse detecting device according to the present invention supports a transmitting / receiving board in which a transmitting piezoelectric element and a receiving piezoelectric element are fixedly mounted on one surface and the other surface is in contact with a living body, and the transmitting / receiving substrate is supported. In addition, a supporting portion that does not contact the transmitting piezoelectric element and the receiving piezoelectric element is provided. According to such a configuration, since both the transmitting piezoelectric element and the receiving piezoelectric element are mounted and fixed on the transmission / reception substrate, these piezoelectric elements can be accurately arranged as designed. In addition, the ultrasonic waves generated by the transmitting piezoelectric element are transmitted into the living body via the transmission / reception board, and the reflected wave due to the blood flow of the living body is also transmitted from the living body to the receiving piezoelectric element via the transmission / reception board. There is no functional problem.

  In addition, the vibration of the transmitting piezoelectric element vibrates in all directions in the resin, but since the back side of the transmitting piezoelectric element is a space, the vibration is transmitted only to the substrate side without waste. Therefore, according to the configuration of the present invention, it is possible to provide a pulse detection device that is unlikely to cause variations in quality, and it is possible to improve pulse detection sensitivity.

  Furthermore, the acoustic impedance of the transmission / reception board is set to a value between the acoustic impedance of each piezoelectric element and the acoustic impedance of the living body. In this way, by setting the acoustic impedance of the transmission / reception board, the ultrasonic waves generated by the transmitting piezoelectric element can be efficiently transmitted to the living body without being reflected at the interface between the transmission / reception board and the living body. The reflected wave due to the pulse can be received by the receiving piezoelectric element with high sensitivity without being reflected at the interface.

  Furthermore, by making the thickness of the transmission / reception substrate about one quarter of the wavelength of the ultrasonic wave generated by the transmitting piezoelectric element, it is possible to reduce the reflection of ultrasonic waves at the interface between the substrate and the living body. The ultrasonic wave is efficiently transmitted into the body, and the reflected wave can be received with high sensitivity by the receiving piezoelectric element.

  Furthermore, it was set as the structure provided with the resin layer in the surface which contact | connects a biological body. By providing the resin layer, the characteristics of the surface in contact with the living body can be optimally adjusted according to the application. For example, by using a silicon-based resin for the resin layer, the adhesion between the transmission / reception substrate and the living body is improved. Accordingly, since the mixing of air is reduced at the interface between the transmission / reception substrate and the living body, the attenuation of the vibration of the ultrasonic wave is reduced, and the ultrasonic wave can be propagated efficiently. In addition, the silicon-based resin has good compatibility with a living body and has little influence even when it is brought into close contact with the skin of the living body.

  Alternatively, the transmission / reception board may be divided, a transmission piezoelectric element may be arranged on one of the divided transmission / reception boards, and a reception piezoelectric element may be arranged on the other transmission / reception board. In this case, the ultrasonic wave generated by the transmitting piezoelectric element is not directly transmitted to the receiving piezoelectric element. Therefore, noise can be reduced and the reliability of the pulse detection device can be improved.

  Further, the other surface of the transmission / reception substrate was formed obliquely with respect to the one surface. For example, the other surface and one surface of the transmission / reception substrate are not parallel surfaces, that is, tapered. Thereby, the Doppler effect of the blood flow of the living body is increased, and the frequency change between the ultrasonic wave generated by the transmitting piezoelectric element and the reflected wave received by the receiving piezoelectric element is increased. Therefore, the pulse detection intensity in the pulse detector is improved.

  Further, the strength of the pulse detecting device against an external impact is improved and the durability is improved by the supporting portion that supports the transmitting piezoelectric element and the receiving piezoelectric element positioned on the transmitting / receiving substrate.

  Moreover, it is good also as a structure provided with the display part which displays the pulse detected by the detection part. Moreover, the living body can easily carry the pulse detecting device by providing the wrist with a belt for mounting the pulse detecting device on the wrist.

  Furthermore, in order to solve the above-described problem, an ultrasonic diagnostic apparatus according to the present invention includes a piezoelectric element (hereinafter referred to as a transmitting piezoelectric element) that transmits ultrasonic waves in a living body in accordance with an input drive signal, and an ultrasonic wave that is a diagnostic site. A piezoelectric element that receives the reflected wave reflected by the laser (hereinafter referred to as a receiving piezoelectric element), a substrate on which the piezoelectric element is provided on one surface, a detection unit that detects a diagnostic site from the reflected wave, and the piezoelectric element The power supply unit for applying the drive signal is provided on the substrate, and the substrate and the piezoelectric element are fixed by the power supply unit.

  According to this configuration, since both the transmitting piezoelectric element and the receiving piezoelectric element are mounted and fixed on the substrate, these piezoelectric elements can be accurately arranged as designed.

  Therefore, according to the configuration of the present invention, it is possible to provide a pulse wave detection device that hardly causes variations in quality. In addition, since the piezoelectric element and the substrate are fixed not by the entire surface of the substrate but by the power feeding unit, the ultrasonic wave does not easily propagate to the substrate, noise can be reduced, and sensitivity can be improved.

  Further, a gap is provided between the substrate and the piezoelectric element. According to this configuration, it is difficult for ultrasonic waves to be transmitted from the transmitting piezoelectric element to the substrate, and the possibility that the ultrasonic waves are transmitted through the substrate and directly received by the receiving piezoelectric element is reduced, thereby reducing noise. And the sensitivity can be improved.

  By using a structure in which the power feeding part protrudes from the piezoelectric element, a structure in which the piezoelectric element faces the power feeding part, or a porous substrate, the ultrasonic wave is further transmitted through the substrate for reception. Since the structure is unlikely to be directly received by the piezoelectric element, noise can be reduced and sensitivity can be improved.

  Further, a groove is provided in a part of the substrate, and the transmitting piezoelectric element and the receiving piezoelectric element are arranged with the groove interposed therebetween. According to this configuration, since the ultrasonic wave generated by the transmitting piezoelectric element is reflected and attenuated by the groove between the transmitting piezoelectric element and the receiving piezoelectric element on the substrate, the ultrasonic wave is transmitted through the substrate. The possibility of being directly received by the receiving piezoelectric element is further reduced. For this reason, detection sensitivity can be improved.

  Alternatively, the substrate may be divided, the transmitting piezoelectric element may be disposed on one of the divided substrates, and the receiving piezoelectric element may be disposed on the other substrate. In this case, the ultrasonic wave generated by the transmitting piezoelectric element is more difficult to be transmitted directly to the receiving piezoelectric element. Therefore, detection sensitivity can be improved.

  In addition, by providing a resin layer on the piezoelectric element installation surface of the substrate, ultrasonic waves are effectively transmitted into the living body. In addition, since the piezoelectric element is arranged on the substrate, the resin layer can be easily arranged with a constant thickness. The resin layer is divided between the transmitting piezoelectric element and the receiving piezoelectric element, and the ultrasonic wave generated by the transmitting piezoelectric element is not easily transmitted directly to the receiving piezoelectric element through the resin layer. did.

  In addition, by providing the support, the strength and handleability of the pulse wave detection device against an external impact are improved.

  In addition, by setting the thickness of the air gap to be equal to or greater than the wavelength λ of the ultrasonic wave, the attenuation is improved, and the ultrasonic wave generated by the transmitting piezoelectric element is less likely to be directly transmitted to the receiving piezoelectric element, thereby improving detection sensitivity. Can be made.

  As described above, according to the pulse detecting device of the present invention, the transmitting piezoelectric element and the receiving piezoelectric element can be accurately arranged as designed on the substrate, so that the pulse detecting device is unlikely to vary in quality. And the pulse detection sensitivity can be improved.

It is an external view which shows the structure of the pulse-wave detection apparatus to which this invention is applied. It is an external view which shows the state which mounted | wore the biological body (arm) with the pulse-wave detection apparatus of this invention. It is a block diagram which shows the internal structure of a process part, and the connection state with a measurement part. It is a figure which shows the structure of the measurement part of the pulse-wave detection apparatus by this invention. It is a top view of a measurement part. It is a figure which shows the state which the measurement part contact | abutted to the biological body. It is a side view which shows the structure of the measurement part which provided the resin layer in the board | substrate. It is a figure which shows the structure which formed the groove | channel in the board | substrate and embedded the piezoelectric element in the groove | channel. It is a figure which shows the structure which joined the board | substrate and the piezoelectric element with the bump. It is a figure which shows the structure of the measurement part which has a board | substrate with which the space | gap was formed by the groove | channel. It is a figure which shows the structure of the measurement part which has a board | substrate with which the projection part was formed. It is a figure which shows the structure of the measurement part which has a surface-treated substrate. It is a figure which shows the structure of the measurement part which has a piezoelectric element in which the space | gap was formed by the groove | channel. It is a figure which shows the structure of the measurement part which has a board | substrate with which the groove | channel was formed. It is a figure which shows the structure of the measurement part which has the divided | segmented board | substrate and a support part. It is a figure which shows the structure of the measurement part which has the divided | segmented board | substrate and a support part. It is a figure which shows the structure of the measurement part which has the divided | segmented board | substrate and a support part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the support part. It is a figure which shows one Example of the support part. It is a figure which shows one Example of the support part. It is a figure which shows one Example of the support part. It is a figure which shows one Example of the support part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the measurement part. It is a figure which shows one Example of the measurement part. It is a figure which shows the state which the measurement part contact | abutted to the biological body. It is a figure which shows the ultrasonic diagnostic apparatus using the conventional piezoelectric element.

  The configuration of the pulse detecting device of the present invention includes a piezoelectric element that transmits an ultrasonic wave into a living body according to an input drive signal, a piezoelectric element that receives a reflected wave reflected by the blood flow of the living body, and these A piezoelectric element is provided on one surface of the substrate, a detection unit for detecting a pulse from the reflected wave, and a power supply unit provided on the substrate for applying a drive signal to the piezoelectric element. It was set as the structure by which the element was fixed by the electric power feeding part. According to this configuration, since both the transmitting piezoelectric element and the receiving piezoelectric element are mounted and fixed on the substrate, these piezoelectric elements can be accurately arranged as designed.

  In addition, since it is fixed only by the power supply unit necessary for inputting the drive signal, the vibration from the transmitting piezoelectric element is difficult to propagate to the entire substrate, so that the ultrasonic wave is transmitted through the substrate and the receiving piezoelectric element. Therefore, it is possible to reduce noise and improve pulse detection sensitivity.

  Furthermore, by providing a gap between the substrate and the piezoelectric element, the possibility that the ultrasonic wave is transmitted through the substrate and directly received by the receiving piezoelectric element is further reduced, so that the sensitivity can be improved.

  In addition, by using a structure in which the power feeding portion protrudes from the piezoelectric element, a structure in which the piezoelectric element protrudes from the power feeding portion, or a porous substrate, ultrasonic waves are transmitted through the substrate to receive the piezoelectric element. Therefore, the sensitivity can be improved.

  Further, by providing a support substrate that supports the substrate, strength and handleability can be improved. Details are described in the examples below.

In addition, the pulse detection device according to the present invention is a piezoelectric element that transmits an ultrasonic wave into a living body according to an input drive electrical signal, or a piezoelectric element that receives a reflected wave reflected by the blood flow of the living body. However, it is provided on one surface of the support portion or the substrate, and a space is formed on the opposite side of the living body with the piezoelectric element as the center.
According to the pulse detecting device having such a configuration, since the piezoelectric elements are placed and fixed on the support portion or the substrate, these piezoelectric elements can be accurately arranged as designed. Therefore, according to the configuration of the present invention, the quality hardly varies and the pulse detection sensitivity can be improved.

  Furthermore, the acoustic impedance of the substrate was set to a value between the acoustic impedance of the piezoelectric element and the acoustic impedance of the living body. Further, the thickness of the substrate was set to about one quarter of the wavelength of the ultrasonic wave generated by the piezoelectric element. In addition, a resin layer is provided on the surface in contact with the living body. Details are described in the examples below.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Example 1
With reference to FIGS. 1-6, the pulse detection apparatus by Example 1 of this invention is demonstrated in detail. First, the external appearance of the pulse detection device 1 will be described with reference to FIGS.

  FIG. 1 is a side view showing an external configuration of a pulse detection device 1 to which the present invention is applied, and FIG. 2 shows a state where the pulse detection device 1 shown in FIG. 1 is attached to a living body 2 (arm). FIG.

  As shown in FIG. 1, the pulse detection device 1 is roughly configured by a processing unit 3, a measurement unit 4, a band 5, and a fastener 6, and as shown in FIG. 2, the pulse detection device 1 includes a living body 2. It can be always carried by attaching to. Here, the processing unit 3 and the measurement unit 4 are attached to the band 5, and are attached to the living body 2 (broken line portion in the figure) by the band 5 and the fastener 6. At this time, the measuring unit 4 is brought into contact with the radial artery or the vicinity of the ulnar artery (not shown) of the living body 2. Although not shown, the processing unit 3 and the measuring unit 4 are connected by a conductive wire, and a voltage signal measured by the measuring unit 4 is input from the processing unit 3 to the measuring unit 4 via this conductive wire. A signal is input to the processing unit 3.

  Next, the processing unit 3 of the pulse detection device 1 will be described with reference to FIG. FIG. 3 is a block diagram illustrating an internal configuration of the processing unit 3 and a connection state between the processing unit 3 and the measurement unit 4. As shown in FIG. 3, the processing unit 3 is schematically configured by a processing calculation unit 31, a drive circuit 32, and a display unit 33.

  The processing calculation unit 31 executes various processings related to pulse detection by executing processing programs stored in a storage area (not shown) provided therein, and displays the processing results on the display unit 33.

  The processing calculation unit 31 causes the transmission piezoelectric element 41 (described later in detail) of the measurement unit 4 to output a specific drive voltage signal from the drive circuit 32 during pulse measurement.

  The processing calculation unit 31 compares the frequency of the ultrasonic wave emitted from the transmitting piezoelectric element 41 with the frequency of the ultrasonic wave received by the receiving piezoelectric element 42 and changed by the Doppler effect of blood flow. Is detected.

  The drive circuit 32 outputs a specific drive voltage signal to the transmission piezoelectric element 41 of the measurement unit 4 in accordance with an instruction from the processing calculation unit 31.

  The display unit 33 is configured by a liquid crystal display screen or the like, and displays a pulse detection result or the like input from the processing calculation unit 31.

  Next, the measurement unit 4 of the pulse detection device 1 will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic diagram illustrating the configuration of the measurement unit 4, and FIG. 5 is a diagram viewed from the upper surface of the measurement unit 4.

  As shown in FIG. 4, the measuring unit 4 is roughly configured by a transmitting piezoelectric element 41, a receiving piezoelectric element 42, and a substrate 43. Here, electrodes 45a and 45b and electrodes 46a and 46b are formed on both surfaces in the thickness direction of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42, respectively. Electrodes 47 a and 47 b and upper surface electrodes 60 a and 60 b are formed on one surface 43 a of the substrate 43, and the electrodes 45 a and 46 a and the upper surface electrodes 60 a and 60 b are electrically connected by a wiring 61. As a material of the substrate 43, a material that is difficult to transmit ultrasonic waves is suitable, but in this embodiment, glass is used. Here, the electrodes 45a, 45b, 46a, 46b, 47a, 47b, 48a, 48b, 60a, 60b are metal films such as Au and Pt, and are formed by a method such as vapor deposition. The wiring 61 is formed by wire bonding such as Au wire.

  Then, as shown in FIG. 5, the transmitting piezoelectric element 41 is placed and fixed on one surface 43a of the substrate 43 so as to overlap the electrode 47a and the fixing portion 62, and the receiving piezoelectric element 42 is fixed by the electrode 47b and the fixing portion 62. It is placed and fixed so as to overlap.

  The same piezoelectric element may be used for the transmitting piezoelectric element 41 and the receiving piezoelectric element 42. Further, the shapes of the piezoelectric elements 41 and 42 are arbitrary, and piezoelectric elements having different shapes for transmission and reception may be used. Further, a plurality of transmission piezoelectric elements and reception piezoelectric elements are provided. You may do it.

  In this example, PZT having a thickness of 0.2 mm (resonance frequency: 9.6 MHz) and an outer shape of 2 × 4 mm is used as a transmitting piezoelectric element and a receiving piezoelectric element, and the substrate 43 has a thickness of 0.5 mm and an outer diameter of 10 mm and 11 mm. A glass substrate was used.

  In addition, the transmitting piezoelectric element 41 has both electrodes 45a and 45b connected to the drive circuit 32 of the processing unit 3 through conductive wires via the electrodes 47a and 60a. When a specific drive voltage signal is applied from the drive circuit 32 to both the electrodes 45a and 45b of the transmission piezoelectric element 41, the transmission piezoelectric element 41 is excited to generate an ultrasonic wave having a specific frequency. (See 2 in FIG. 6). In this embodiment, excitation was performed at 9.6 MHz. In the receiving piezoelectric element 42, both electrodes 46a and 46b are connected to the processing operation unit 31 of the processing unit 3 via conductive wires via the electrodes 47b and 60b. When receiving the ultrasonic wave from the living body, the receiving piezoelectric element 42 converts the ultrasonic wave into a voltage signal and outputs the voltage signal to the processing calculation unit 31 of the processing unit 3.

  Next, operations of the processing unit 3 and the measurement unit 4 in the pulse detection device 1 will be described with reference to FIGS. 3 and 6. FIG. 6 shows the positional relationship between the measurement unit 4 and the living body 2 of the pulse detection device according to this embodiment, and the electrodes 45a, 45b, 46a, 46b, 60a, 60b, and the wiring 61 are omitted.

  First, when the pulse detection device 1 is attached to a living body, as shown in FIG. 6, the measuring unit 4 is brought into contact with the living body 2 (in the vicinity of the radial artery or the ulnar artery). When the pulse is detected, the processing calculation unit 31 shown in FIG. 3 causes the drive circuit 32 to output a specific drive voltage signal to both electrodes 45a and 45b (see FIG. 5) of the transmission piezoelectric element 41.

  The transmitting piezoelectric element 41 is excited according to the drive voltage signal input to both electrodes 45a and 45b to generate an ultrasonic wave, and transmits the ultrasonic wave into the living body 2 (see FIG. 6). The ultrasonic wave transmitted into the living body 2 is reflected by the blood flow 2 a and received by the receiving piezoelectric element 42 of the measuring unit 4. The receiving piezoelectric element 42 converts the received ultrasonic wave into a voltage signal, and outputs the voltage signal to the processing calculation unit 31 from both electrodes 46 and 46 (see FIG. 5).

  Next, the processing operation unit 31 compares the frequency of the ultrasonic wave transmitted from the transmitting piezoelectric element 41 with the frequency of the ultrasonic wave received by the receiving piezoelectric element 42 and changed due to the Doppler effect of blood flow. Detects the pulse of a living body. Then, the processing calculation unit 31 displays the pulse detection result on the display unit 33.

  In this way, the pulse detection device 1 measures and displays the pulse of the living body.

  Next, a method for manufacturing the measuring unit 4 of the pulse detecting device according to this embodiment will be described. The transmitting piezoelectric element 41 and the receiving piezoelectric element 42 form electrodes 45a, 45b, 46a, 46b by vacuum deposition of a metal such as aluminum or Au, and cut the outer shape by dicing or the like. For the substrate 43, electrodes such as aluminum and Au are formed on the surface 43a by vacuum deposition, and electrodes 47a, 47b, 60a and 60b are formed on the one surface 43a by a thin film process such as etching.

  The transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are fixed to the substrate 43 by fixing the electrodes 45 b and 45 b and the electrodes 47 a and 47 b with a conductive adhesive or the like in the fixing portion 62.

  Further, the electrodes 47 a and 60 a are connected to the drive circuit 32 of the processing unit 3 in FIG. 3 by wiring not shown, and the electrodes 47 b and 60 b are connected to the processing circuit 31.

  As described above, in this embodiment, the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are arranged on the substrate 43.

  Therefore, since the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 can be accurately arranged on the substrate 43, it is possible to provide the pulse detecting device 1 in which the quality of the measuring unit 4 is stable and the quality does not vary. Moreover, since it is fixed to the substrate 43 only by the fixing portion 62 of FIG. 5, it is difficult for the ultrasonic wave to propagate directly to the substrate 43 and noise is reduced, so that the pulse detection sensitivity can be improved. In the case of the present embodiment, the size of the transmitting piezoelectric element and the receiving piezoelectric element is 2 × 4 mm, the substrate size is 10 × 11 mm, and the area of the fixed portion 62 is 0.5 mm × 0.5 mm.

  When the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are fixed to the substrate 43 with a conductive adhesive or the like on the entire surface, a ± 5 V, 9.5 MHz burst signal (sign of 5 waves) is applied to the transmitting piezoelectric element 41. When a pulse is input, a burst signal having an amplitude of 0.8% of the input is received by the receiving piezoelectric element 42 in a state where the pulse is not measured (non-measurement state). As described above, when only the fixing unit 62 was fixed, the amplitude of the burst signal detected by the receiving piezoelectric element was reduced to 0.02% of the input.

  Further, by using the measurement 4 of this embodiment, the reflection intensity of the ultrasonic wave to the Cu plate installed in the silicon oil (the ultrasonic wave transmitted from the transmission piezoelectric element 41 is reflected on the Cu plate and received by the piezoelectric element) When the entire surface was fixed to the substrate 43, the ratio was 0.2%. However, as in the present embodiment, the fixing portion 62 alone was fixed to 0.6%. As a result, the reflection intensity increased about three times, and as a result, the pulse detection sensitivity was improved.

  Further, since it is not embedded and fixed in resin as in the prior art, electrodes can be easily formed on both surfaces of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42, and the electrodes can be easily pulled out from each piezoelectric element.

  In addition, the pulse detection device of this embodiment normally measures and displays a pulse, but can also measure a pulse wave.

  Moreover, you may comprise as a module instead of making it the structure which left | separated the process part 3 and the measurement part 4 in the pulse detection apparatus 1 like a present Example. Thereby, the number of parts of the pulse detection device 1 is reduced, and the manufacturing cost can be suppressed. Furthermore, the wiring between the processing unit 3 and the measurement unit 4 can be simplified.

  In addition, a communication unit or the like may be provided in the processing unit 3 to transmit the pulse measurement result to a management system in the hospital, thereby constantly grasping the state of the patient wearing the pulse detection device 1. Can do.

  In addition, about the detailed part of a present Example, it is not limited to the content of the said Example, It can change suitably in the range which does not deviate from the summary of this invention. For example, in this embodiment, the excitation frequency of the piezoelectric element is 9.6 MHz, but there is no particular problem even if the excitation frequency is set to about 5 MHz using a piezoelectric element having a resonance frequency of about 5 MHz.

(Example 2)
A second embodiment of the pulse detecting device according to the present invention will be described with reference to FIGS. FIG. 7 is a side view of the measurement unit 4 related to the pulse detection device of this embodiment, and the electrodes 45a, 45b, 60a, 60b, 46a, 46b, 47a, 47b, and the wiring unit 61 are omitted. The processing part, band and stopper, piezoelectric element, substrate material and shape were the same as those in Example 1.

  FIG. 7 is a diagram illustrating a configuration of the measurement unit 4 in which the resin layer 49 is provided on the one surface 43 a of the substrate 43. As shown in FIG. 7, a resin layer 49 is formed on one surface 43 a of the substrate 43. Here, the resin layer 49 is made of an epoxy-based resin or a silicon-based resin, protects the transmitting piezoelectric element 41 and the receiving piezoelectric element 42, and provides electrodes 45a, 45b, 60a, 60b, 46a, 46b, 47a, 47b, and wiring. There is an effect of insulating the part 61 and an effect of efficiently transmitting ultrasonic waves between the living body and each of the piezoelectric elements 41 and 42.

  In order to efficiently propagate ultrasonic waves between the living body and each of the piezoelectric elements 41 and 42, the acoustic impedance of the resin layer 49 is set to a value between the acoustic impedance Zl of the living body and the acoustic impedance Zc of the piezoelectric element. There is a need. The acoustic impedance is a value indicating the ease of propagation of sound waves, and the value varies depending on the Young's modulus and density.

And in the measurement part 4 which has the structure shown in FIG. 7, the ideal acoustic impedance Zm of the board | substrate 43 is
Zm = (Zc × Zl) ^1/2 can be expressed by the equation (1). Substituting Zl = 1.5 M (N · sec / m ³ ) and Zc (using PZT) = 30 M (N · sec / m ³ ) into equation (1), Zm = approximately 6. 7M (N · sec / m ³ ).

Based on this calculated value, in the present embodiment, an epoxy resin having an acoustic impedance of about 3 M (N · sec / m ³ ) is used for the substrate 43.

  Further, the thickness of the resin layer 49 in the substrate thickness direction is preferably as small as possible, and in the configuration as in the present embodiment, 100 μm or less is appropriate. By applying the resin 49 onto the substrate 43 by spin coating or bar coating, and curing the resin 49 with heat or ultraviolet rays, the resin layer 49 can be uniformly arranged with a certain thickness.

  Note that an epoxy resin layer may be formed on one surface 43a of the substrate 43, and a silicon resin layer may be further formed thereon to form two resin layers. Attenuation can be prevented.

  When a silicon resin is used for the resin layer 49, since the silicon resin is soft, the resin layer 49 improves the adhesion between the substrate 43 and the living body. Therefore, an air layer existing between the living body and the substrate 43 can be reduced, and attenuation of ultrasonic vibrations by the air layer can be suppressed. In addition, the silicon-based resin has good compatibility with a living body and has little influence even when it is brought into close contact with the skin.

(Example 3)
A third embodiment of the measurement unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 8 is a side view of the measurement unit 4 related to the pulse detection device of the present invention, in which the wiring unit 61 and the electrodes 60a and 60b are omitted. The processing part, band and stopper, piezoelectric element, substrate material and shape were the same as those in Example 1. In the pulse detecting device of this embodiment, a groove is formed on the substrate 43, electrodes 47a and 47b are formed in the groove, the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are disposed in the groove, and the substrate A resin layer 49 is attached on 43. By embedding the piezoelectric element in the groove in this way, unevenness due to the piezoelectric element is not formed, and the resin layer 49 can be formed more uniformly.

Example 4
A fourth embodiment of the measurement unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 9 is a side view of the measurement unit 4 related to the pulse detection device of the present invention. The processing unit, band and stopper, piezoelectric element, substrate material and shape are the same as those in Example 1, and the electrode 60a is used. 60b and the wiring part 61 are omitted. In this embodiment, bumps 71 such as solder are formed on the electrodes 47a and 47b. The transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are fixed to the electrodes 47a and 47b by bumps 71, and a gap 70 is formed between the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 and the electrodes 47a and 47b. .

  In the present embodiment, the bump 71 is formed by solder, and the height of the bump 71 is 10 μm.

  The air layer has a very high attenuation rate of ultrasonic waves. For this reason, the presence of the air gap 70 as an air layer reduces the possibility that ultrasonic waves are transmitted through the substrate 43 and directly received by the receiving piezoelectric element 42, thereby preventing pulse measurement noise.

  In this embodiment, bumps are formed on both the transmitting piezoelectric element 41 and the receiving piezoelectric element 42, but the same effect can be obtained with either one. Further, a resin layer may be provided as in the second embodiment.

(Example 5)
Embodiment 5 of the measurement unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 10 is a side view of the measurement unit 4 related to the pulse detection device of this embodiment. The materials for the processing section, band, stopper, piezoelectric element, and substrate were the same as those in the first embodiment. The electrodes 60a and 60b and the wiring part 61 are omitted. The pulse detecting device of this embodiment has a configuration in which a gap 70 is provided between the substrate 43, the transmitting piezoelectric element 41 and the receiving piezoelectric element 42. A gap 70 is formed on the substrate 43, and the transmission piezoelectric element 41 and the electrode 47 a, and the reception piezoelectric element 42 and the electrode 47 b are arranged across the gap 70.

  Since the air layer has a very high attenuation rate with respect to the ultrasonic wave, the air gap 70 reduces the possibility that the ultrasonic wave is transmitted through the substrate 43 and directly received by the receiving piezoelectric element 42, thereby preventing pulse measurement noise. Can do. Furthermore, the detection sensitivity can be improved.

  The distance propagation characteristic of the ultrasonic wave is preferably an odd multiple of 1/4 of the wavelength λ corresponding to the antinode of the wave, and about 1/4 is particularly suitable. On the other hand, it is known that ultrasonic waves attenuate as the distance increases in gas, liquid, and solid. In the present embodiment, as the thickness (depth) of the gap 70, the ultrasonic wave is sufficiently attenuated when the ultrasonic wave has a wavelength λ or more, and good characteristics are obtained. For example, when 9.5 MHz ultrasonic waves are used, the thickness (depth) of the gap 70 is suitably 0.2 mm or more.

  In this embodiment, when a burst signal (sine wave for 5 waves) of ± 5 V and 9.5 MHz is input to the transmitting piezoelectric element 41, 0.02% of the signal is transmitted at the time of non-measurement. To the receiving piezoelectric element 42, and the reflection intensity of the ultrasonic wave to the Cu plate installed in the silicon oil (the ultrasonic wave transmitted from the transmitting piezoelectric element 41 is reflected on the Cu plate to receive the piezoelectric element). The ratio detected by 42) was measured to be 0.7%, and the reflection intensity was further improved.

  In this embodiment, the gap 70 is formed by dicing the substrate 43, but other processing methods may be used, and the depth of the gap 70 is about 0.2 mm. Further, a resin layer may be provided as in the second embodiment.

(Example 6)
A sixth embodiment of the measurement unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 11 is a side view of the measurement unit 4 related to the pulse detection device of this embodiment, and the electrodes 47a and 47b, the electrodes 60a and 60b, and the wiring unit 61 are omitted. The same materials as in Example 1 were used for the processing section, band, stopper, piezoelectric element, and substrate.

  In the pulse detecting device according to the present embodiment, a protrusion 72 is provided on the substrate 43 with respect to the transmitting piezoelectric element 41 and the receiving piezoelectric element 42. Since the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are fixed only at the protrusions 72, the ultrasonic waves emitted by the transmitting piezoelectric element 41 are difficult to be transmitted directly to the receiving piezoelectric element 42, and thus pulse measurement noise. Can be prevented.

  In this embodiment, the protrusion 72 is formed by plating a metal such as copper on the substrate 43. However, the protrusion 72 may be formed on the substrate 43 by dicing or the like. Further, a resin layer may be provided as in the second embodiment.

(Example 7)
A seventh embodiment of the measuring unit 4 of the pulse detecting device 1 according to the present invention will be described with reference to FIG. FIG. 12 is a side view of the measurement unit 4 related to the pulse detection device of this embodiment, and the electrodes 60a and 60b and the wiring unit 61 are omitted. The same materials as in Example 1 were used for the band, stopper, processing section, piezoelectric element, and substrate.

  In the pulse detecting device according to this embodiment, the surface 43a of the substrate 43 is surface-treated with a certain roughness by grinding or the like. An electrode (not shown) is provided on one surface 43a of the substrate 43, and surface treatment is performed with a certain roughness by grinding or the like, and the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are placed on the one surface 43a with a conductive adhesive or the like. Fixed. As a result, the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 come into contact with the substrate 43 via the electrodes 45b and 46b in a very limited area, and the ultrasonic waves generated by the transmitting piezoelectric element 41 are transmitted. Since it is difficult to transmit directly to the receiving piezoelectric element 42, pulse measurement noise can be prevented. Furthermore, the detection sensitivity can be improved.

(Example 8)
An embodiment of the measurement unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 13 is a side view of the measurement unit 4 related to the pulse detection device according to the eighth embodiment of the present invention, in which the electrodes 60a and 60b and the wiring unit 61 are omitted. The material, shape of the band, processing part, stopper, and substrate were the same as in Example 1.

  In the pulse detecting device according to the present embodiment, grooves are formed on the electrodes 45 b and 46 b side of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42, and are fixed via the electrodes 47 a and 47 b and the gap 70. The gap 70 was created by forming grooves on the electrode 45b and electrode 46b sides of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 by dicing.

  The air layer has an extremely high attenuation rate with respect to ultrasonic waves, and the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are fixed via the gap 70, so that the ultrasonic waves are attenuated in the gap 70 and emitted by the transmitting piezoelectric element 41. Since the transmitted ultrasonic wave is not easily transmitted directly to the receiving piezoelectric element 42, it is possible to prevent pulse measurement noise. Further, a resin layer may be provided as in the second embodiment.

  Further, a resin layer may be provided as in the second embodiment. Further, only the portion corresponding to the gap 70 of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 may be subjected to polarization processing in the thickness direction of the piezoelectric element. In this case, the above effect can be further improved.

Example 9
Embodiment 9 of the measuring unit 4 of the pulse detecting device 1 according to the present invention will be described with reference to FIG. FIG. 14 is a side view of the measurement unit 4, and the electrodes 60 a and 60 b and the wiring unit 61 are omitted. The material and shape of the piezoelectric element and the substrate were the same as those in Example 1.

  In the pulse detecting device according to this embodiment, a groove 50a is formed on the substrate 43, and the electrode 45b, the electrode 46b, the electrode 47a, and the electrode 47b of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are fixed through the groove 50a. This is the configuration. Therefore, the ultrasonic wave emitted by the transmitting piezoelectric element 41 at the time of detecting the pulse is reflected and attenuated by the groove portion 50a of the substrate 43, so that the ultrasonic wave is transmitted through the transmitting / receiving substrate 50 and received by the receiving piezoelectric element 42. The possibility of direct reception is reduced, and pulse measurement noise can be prevented.

  In this embodiment, the groove 50a is processed into the substrate 43 by dicing. Further, a resin layer may be provided as in the second embodiment.

(Example 10)
An embodiment 10 of the measuring unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 15 is a perspective view illustrating a schematic configuration of the measurement unit 4 related to the pulse detection device of the present embodiment. The same band, stopper, processing section, and piezoelectric element as in Example 1 were used.

  In the pulse detection device according to this embodiment, the substrate 43 is divided into the transmitting piezoelectric element 41 side and the receiving piezoelectric element 42 side, and a support body 81 is attached to the other surface of the substrate 43. As shown in FIG. 15, the support body 81 has a concave shape, and a gap 80 is formed between the substrate 43 and the support body 81. Even if the substrate 43 is divided as shown in FIG. 15, the substrate 43 can be easily and accurately installed. Also, it is possible to improve the transmission and reception intensity of ultrasonic waves.

  When the area of the opening of the recess 82 of the support 81 (L × M in FIG. 22) is smaller than the areas of the transmission piezoelectric element 41 and the reception piezoelectric element, the ultrasonic wave is transmitted through the side wall 83 of the support 81. End up. Therefore, it is desirable that the area of the recess 82 is larger than the total area of the transmitting piezoelectric element 41 and the receiving piezoelectric element 42.

  When a ± 5 V, 9.5 MHz burst signal (5 sine waves) is inputted to the transmitting piezoelectric element 41, in this embodiment, the amplitude of the burst signal detected by the receiving piezoelectric element is 0 of the input. Reduced to 0.01%. Furthermore, using the measuring unit 4 according to the present embodiment, the reflection intensity of the ultrasonic wave to the Cu plate installed in the silicon oil (the ultrasonic wave transmitted from the transmitting piezoelectric element 41 is reflected by the Cu plate and received by the receiving piezoelectric element). The ratio detected by 42) was measured and improved to 1.0%.

  Even if the ultrasonic wave transmitted from the transmitting piezoelectric element 41 is transmitted to the substrate 43, the ultrasonic wave is attenuated and does not propagate to the support 81 because there is a gap 80 between the substrate 43 and the support 81. This makes it difficult for the ultrasonic waves generated by the transmitting piezoelectric element 41 to be directly transmitted to the receiving piezoelectric element 42, thereby preventing pulse measurement noise. Furthermore, the detection sensitivity can be improved.

  In this embodiment, acrylic is used as the support 81. However, when the support 81 is formed of a porous body that easily attenuates the ultrasonic wave, the ultrasonic wave emitted from the transmission piezoelectric element 41 is further directly received by the piezoelectric element. Since it becomes difficult to transmit to 42, the noise of pulse measurement can be prevented. Further, a resin layer may be provided as in the second embodiment.

(Example 11)
Embodiment 11 of the measuring unit 4 of the pulse detecting device 1 according to the present invention will be described with reference to FIG. FIG. 16 is a perspective view showing a schematic configuration of the measurement unit 4 related to the pulse detection device of the present embodiment. The same materials as in Example 1 were used for the band, processing section, stopper, piezoelectric element, and substrate.

  In the measurement unit of the pulse detecting device according to the present embodiment, the substrate 43 is divided into the transmitting piezoelectric element 41 side and the receiving piezoelectric element 42 side, and a support 89 is provided on the other surface of the substrate 43 via a column 83. It is an attached configuration. Even if the substrate 43 is divided as shown in FIG. 16, the substrate 43 can be easily and accurately installed, and the transmission and reception intensity of ultrasonic waves can be improved.

  As shown in FIG. 16, the support 89 is attached to the substrate 43 via the support column 83. Even if the ultrasonic wave transmitted from the transmitting piezoelectric element 41 is transmitted to the substrate 43, the ultrasonic wave is attenuated and does not propagate to the support 89 because there is a gap 80 between the substrate 43 and the support 89. . For this reason, the ultrasonic waves emitted from the transmitting piezoelectric element 41 are not easily transmitted directly to the receiving piezoelectric element 42, so that pulse measurement noise can be prevented. Furthermore, the detection sensitivity can be improved.

  In this embodiment, acrylic is used for the support 89. However, if the support 89 is made of a porous material that easily attenuates the ultrasonic wave, the ultrasonic wave emitted by the transmission piezoelectric element 41 is directly applied to the reception piezoelectric element 42. Since it becomes difficult to transmit, pulse measurement noise can be prevented. Further, a resin layer may be provided as in the second embodiment.

(Example 12)
Embodiment 12 of the measurement unit 4 of the pulse detection device 1 according to the present invention will be described with reference to FIG. FIG. 17 is a side view of the measurement unit 4 related to the pulse detection device of this embodiment. The same materials as in Example 1 were used for the band, processing section, stopper, piezoelectric element, and substrate. The electrodes 45a, 45b, 46a, 46b, 60a, 60b, and the wiring part 61 are omitted.

  In the measurement unit of the pulse detecting device according to the present embodiment, the substrate 43 is divided into the transmitting piezoelectric element 41 side and the receiving piezoelectric element 42 side, a support 89 is attached to the other surface of the substrate 43, and a resin layer Reference numeral 49 denotes a configuration in which the transmission piezoelectric element 41 side and the reception piezoelectric element 42 side are separately provided. By dividing the resin layer on the substrate 43, ultrasonic waves received from the transmitting piezoelectric element 42 without being propagated from the transmitting piezoelectric element 41 through the resin layer 49 into the living body can be reduced. There is an effect of improving the detection sensitivity. The support 81 is made of a porous material such as ceramic, or a material that easily attenuates ultrasonic waves, such as rubber, so that the support 81 is propagated from the transmitting piezoelectric element 41 to the receiving piezoelectric element 42. Can be prevented from propagating.

(Example 13)
Hereinafter, embodiments of a pulse detection device according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a side view showing an external configuration of the pulse detection device 1 according to the present invention. Moreover, the state which mounted | wore the biological body 2 (arm) with the pulse detection apparatus 1 shown in FIG. 1 is shown in FIG.

  As shown in FIG. 1, the pulse detection device 1 is roughly configured by a processing unit 3, a measurement unit 4, a band 5, and a fastener 6. As shown in FIG. 2, the pulse detection device 1 can be always carried by being attached to the living body 2. The processing unit 3 and the measurement unit 4 are attached to a band 5 and are attached to the living body 2 (broken line portion in FIG. 1) by the band 5 and the fastener 6. At this time, the measuring unit 4 is brought into contact with the radial artery or the vicinity of the ulnar artery (not shown) of the living body 2. Although not shown, the processing unit 3 and the measuring unit 4 are connected by a conductive wire, and a voltage signal measured by the measuring unit 4 is input from the processing unit 3 to the measuring unit 4 via this conductive wire. A signal is input to the processing unit 3.

  FIG. 3 is a block diagram showing an internal configuration of the processing unit 3 of the pulse detection device 1 and a connection state between the processing unit 3 and the measuring unit 4. As shown in the drawing, the processing unit 3 is schematically configured by a processing calculation unit 31, a drive circuit 32, and a display unit 33.

  The processing calculation unit 31 executes various processings related to pulse detection by executing processing programs stored in a storage area (not shown) provided therein, and displays the processing results on the display unit 33. Further, the processing calculation unit 31 causes the drive circuit 32 to output a specific drive voltage signal to the transmission piezoelectric element 41 (details will be described later) of the measurement unit 4 during pulse measurement. The processing calculation unit 31 detects the pulse by comparing the frequency of the ultrasonic wave emitted from the transmitting piezoelectric element 41 with the frequency of the ultrasonic wave received by the receiving piezoelectric element 42 and changed by the Doppler effect of blood flow. To do.

  The drive circuit 32 outputs a specific drive voltage signal to the transmission piezoelectric element 41 of the measurement unit 4 in accordance with an instruction from the processing calculation unit 31.

  The display unit 33 is configured by a liquid crystal display screen or the like, and displays a pulse detection result or the like input from the processing calculation unit 31.

  Next, a cross-sectional view of the measuring unit 4 of the pulse detection device 1 is shown in FIG. The transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are bonded to a transmitting / receiving substrate 44, and the transmitting / receiving substrate 44 is held by a support portion 81. With this configuration, a space 80 is formed on one surface of each piezoelectric element, and the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 can transmit only in the direction in which ultrasonic waves are transmitted and received.

  There are a method using various adhesives and a method using diffusion bonding or eutectic bonding for joining the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 to the transmitting / receiving substrate 44. Diffusion bonding is a method in which two metals are pressurized and heated in contact with each other, thereby causing thermal diffusion of metal atoms to occur between the mutual metals and bonding. Eutectic bonding is a method in which two metals are pressed and heated in contact with each other to melt each other's metals and then cooled to form an alloy between the two metals, thereby joining them. . The advantage of using diffusion bonding and eutectic bonding when bonding the transmitting / receiving substrate 44 and the transmitting piezoelectric element 41 or the receiving piezoelectric element 42 is that an adhesive layer is not formed at the bonding interface, and ultrasonic waves at the bonding interface are not formed. The vibration attenuation can be reduced. The shapes of the piezoelectric elements 41 and 42 are arbitrary, and piezoelectric elements having different shapes for transmission and reception may be used.

  Further, the transmitting piezoelectric element 41 is electrically connected to the drive circuit 32 of the processing unit 3 through a conductive wire. When a specific drive voltage signal is applied to the transmission piezoelectric element 41 from the drive circuit 32, the transmission piezoelectric element 41 is excited to generate an ultrasonic wave having a specific frequency, and the living body (2 in FIG. 31). Send to.

  The receiving piezoelectric element 42 is electrically connected to the processing calculation unit 31 of the processing unit 3 by a conductive wire. When receiving the ultrasonic wave from the living body, the receiving piezoelectric element 42 converts the ultrasonic wave into a voltage signal and outputs the voltage signal to the processing calculation unit 31 of the processing unit 3.

  The transmission / reception substrate 44 has a transmission piezoelectric element 41 and a reception piezoelectric element 42 disposed on one surface 43a, and the other surface 43b is a glass substrate that is in contact with a living body.

  Here, in order to efficiently transmit ultrasonic waves between the living body and each of the piezoelectric elements 41 and 42 via the transmission / reception substrate 44, the acoustic impedance of the transmission / reception substrate 44 is set to the acoustic impedance Zl of the living body and the acoustic of the piezoelectric element. It is necessary to set a value between the impedance Zc. The acoustic impedance is a value indicating the ease of propagation of sound waves, and the value varies depending on the Young's modulus and density.

And in the measurement part 4 which has the structure shown in FIG. 18, the ideal acoustic impedance Zm of the transmission / reception board | substrate 44 can be shown by Zm = (Zc * Zl) ^1/2 Formula (1).

Then, when Zl = 1.5M (N · sec / m ³ ), which is well-known in the above formula (1), and Zc = 30M (N · sec / m ³ ) when PZT is used, Zm is about It becomes 6.7M (N · sec / m ³ ).

Based on this calculated value, in the present embodiment, a glass substrate having an acoustic impedance of about 10 M (N · sec / m ³ ) is used as the transmission / reception substrate 44.

  Further, the thickness of the transmission / reception substrate 44 is also an important factor with respect to the propagation of ultrasonic waves. When the thickness of the transmission / reception substrate 44 is inappropriate, reflection of ultrasonic waves occurs in the transmission / reception substrate 44 as in the above-described acoustic impedance, and the ultrasonic waves do not propagate efficiently. Therefore, the thickness of the transmission / reception substrate 44 is preferably about ¼ of the wavelength at the frequency of the ultrasonic wave that the transmission / reception substrate 44 propagates. Specifically, when the ultrasonic frequency is 9 MHz (usually 2.3 to 10 MHz ultrasonic waves are used) and the speed of sound on the transmission / reception substrate (glass substrate) is about 5000 m / sec, the thickness of the transmission / reception substrate 44 is It is about 140 μm.

  Further, a resin layer 48 is formed on the surface of the transmitting / receiving substrate 44 opposite to the surface on which the piezoelectric elements are formed, that is, the surface in contact with the living body. Here, the resin layer 48 is made of an epoxy-based resin or a silicon-based resin, and the nature of the contact surface (other surface 43b) with the living body of the transmission / reception substrate 44 varies depending on the type of resin used.

  For example, when an epoxy resin is used for the resin layer 48, the acoustic impedance of the epoxy resin is a value between the acoustic impedance of the transmission / reception board 44 and the acoustic impedance of the living body. The ultrasonic reflection that occurs can be further reduced. Therefore, it is possible to efficiently propagate ultrasonic waves between the living body and the transmission / reception substrate 44. Here, the ideal acoustic impedance of the resin layer 48 is calculated by the same formula as the formula (1) described above.

  Further, when a silicon resin is used for the resin layer 48, the silicon resin is soft, so that the adhesion between the transmission / reception substrate 44 and the living body is improved by the resin layer 48. Therefore, an air layer existing between the living body and the transmission / reception substrate 44 can be reduced, and attenuation of ultrasonic vibration by the air layer can be suppressed. In addition, the silicon-based resin has good compatibility with a living body and has little influence even when it is brought into close contact with the skin.

  Note that an epoxy resin layer may be formed on the other surface of the transmission / reception substrate 44, and a silicon resin layer may be further formed thereon to form two resin layers, thereby reflecting the ultrasonic wave. Can prevent attenuation.

  Next, operations of the processing unit 3 and the measurement unit 4 in the pulse detection device 1 will be described with reference to FIGS. 3 and 31.

  First, when the pulse detection device 1 is attached to a living body, as shown in FIG. 31, the measuring unit 4 is brought into contact with the living body 2 (near the radial artery or the ulnar artery). When the pulse is detected, the processing calculation unit 31 illustrated in FIG. 3 causes the transmission piezoelectric element 41 to output a specific drive voltage signal from the drive circuit 32.

  The transmission piezoelectric element 41 generates an ultrasonic wave based on the input drive voltage signal, and transmits the ultrasonic wave into the living body 2 via the transmission / reception substrate 44. The ultrasonic wave transmitted into the living body 2 is reflected by the blood flow 2 a and received by the receiving piezoelectric element 42 of the measuring unit 4. The reception piezoelectric element 42 converts the received ultrasonic wave into a voltage signal and outputs the voltage signal to the processing calculation unit 31.

  Next, the processing calculation unit 31 compares the ultrasonic frequency transmitted from the transmitting piezoelectric element 41 with the ultrasonic frequency received by the receiving piezoelectric element 42 and changed by the Doppler effect of blood flow. Detect pulse. Then, the processing calculation unit 31 displays the pulse detection result on the display unit 33. In this way, the pulse detection device 1 measures and displays the pulse of the living body.

  Therefore, since the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 can be accurately arranged on the transmission / reception substrate 44, the pulse detecting device 1 in which the quality of the measuring unit 4 is stable and the quality does not vary is provided. In addition, the pulse detection sensitivity can be improved.

  Moreover, by providing the pulse detection device 1 with the support portion, the strength of the pulse detection device 1 is improved, and the durability of the pulse detection device 1 is improved.

  Further, the pulse detection device 1 of the present embodiment normally measures and displays a pulse, but can also measure a pulse wave.

In addition, about the detailed part of the pulse detection apparatus of this invention, it is not limited to the content of the said Example, It can change suitably in the range which does not deviate from the summary of this invention. For example, in this embodiment, the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are joined to each other on the transmission / reception substrate 44 by metal-to-metal bonding, but may be joined by hydrogen bonding. Here, the hydrogen bonds, with the ion source of water ionized hydroxide ions OH ^- generate, the hydroxide ion OH ^- after irradiation with on reception substrate 44 includes a transceiver substrate 44 each In this method, the piezoelectric elements 41 and 42 are joined by pressure contact. Alternatively, a hydrophilic group may be formed on the transmission / reception substrate 44, and the transmission / reception substrate and each of the piezoelectric elements 41 and 42 may be joined by hydrogen bonding using the hydrophilic group.

  Further, as in the present embodiment, the processing unit 3 and the measurement unit 4 of the pulse detection device 1 may be configured as one module instead of being separated from each other. Thereby, the number of parts of the pulse detection device 1 is reduced, and the manufacturing cost can be suppressed. Furthermore, the wiring between the processing unit 3 and the measurement unit 4 can be simplified.

  In addition, a communication unit or the like may be provided in the processing unit 3 to transmit the pulse measurement result to a management system in the hospital, thereby constantly grasping the state of the patient wearing the pulse detection device 1. Can do.

(Example 14)
Moreover, the modification of the structure of the measurement part 4 shown in FIG. 18 is demonstrated with reference to FIGS. In the following description, the same components as those of the measurement unit 4 shown in FIG. 18 are denoted by the same reference numerals, and description thereof is omitted here.

  FIG. 19 is a diagram illustrating a configuration of the measurement unit 4 in which the transmission piezoelectric element 41 and the reception piezoelectric element 42 are arranged with a groove 43c formed on the transmission / reception substrate 44 interposed therebetween.

  As shown in FIG. 19, a groove 43c is formed on the transmission / reception substrate 44, and the transmission piezoelectric element 41 and the reception piezoelectric element 42 are arranged with the groove 43c interposed therebetween.

  Therefore, since the ultrasonic wave emitted by the transmitting piezoelectric element 41 at the time of detecting the pulse is reflected and attenuated by the groove 43c of the transmitting / receiving substrate 44, the ultrasonic wave is transmitted through the transmitting / receiving substrate 44 and received piezoelectrically. The possibility of being directly received by the element 42 is reduced, and pulse measurement noise can be prevented. Furthermore, the detection sensitivity can be improved.

  In addition, about the shape of the groove part 43c, it is arbitrary, for example, the cross-sectional shape of the groove part 43c may be an inverted triangle.

(Example 15)
FIG. 20 is a diagram illustrating a configuration of the measurement unit 4 in which the transmission piezoelectric element 41 and the reception piezoelectric element 42 are respectively arranged on the divided transmission / reception boards 44 and 45. As shown in FIG. 20, the measurement unit 4 divides the transmission / reception board 44 (FIG. 18) into two transmission / reception boards 44 and 45, arranges the transmission piezoelectric element 41 on the transmission board 44, and receives the reception board 45. The receiving piezoelectric element 42 is disposed on the surface.

  Therefore, since the ultrasonic wave generated by the transmitting piezoelectric element 41 during pulse detection is not directly transmitted to the receiving piezoelectric element 42, pulse measurement noise can be prevented.

(Example 16)
FIG. 21 is a diagram illustrating a configuration of the measurement unit 4 having a tapered shape on each of the divided transmission substrate 44 and reception substrate 45. As shown in FIG. 21, the measurement unit 4 divides the transmission / reception substrate 44 (FIG. 18) into two transmission / reception substrates 44 and 45, and arranges the transmission piezoelectric element 41 on one surface 44 a of the transmission substrate 44. The receiving piezoelectric element 42 is disposed on the one surface 45 a of the receiving substrate 45. And the other surface 44b of the transmission / reception board | substrate 44 and the other surface 45b of the transmission / reception board | substrate 45 were made into the taper shape. Here, these tapered shapes are formed along the blood flow direction of the living body, and are formed such that the outer thickness is larger than the inner thickness of each of the transmission / reception substrates 44 and 45. This makes it easier to focus the ultrasonic wave emitted from the transmitting piezoelectric element 41 in the vicinity of the blood flow of the living body, and allows the receiving piezoelectric element 42 to efficiently receive the ultrasonic wave reflected by the blood flow of the living body. .

  Further, the structure of the support portion 81 is not limited to the concave shape as illustrated in FIGS. 18 to 21 (FIG. 22), and the case shape illustrated in FIG. 23 may be used. By using the configuration shown in FIG. 23, a pulse detector with higher durability can be obtained.

  Further, as shown in FIG. 24, by making the support portion 81 comb-like, the area for holding the substrate is reduced, ultrasonic waves do not leak from the transmission side to the reception side, noise is reduced, and higher A high-performance pulse detector can be created. As shown in FIG. 25, when the tip of the comb-like shape has an acute angle, the pulse detecting device has a smaller noise.

  As the material of the support portion 81, any one of a metal material, an organic material, an inorganic material, or a composite material thereof is used. If ceramics are used for the support, the strength of the pulse detector increases because the ceramics are hard. If plastic is used for the support part, it is suitable for mass production and the cost is reduced. In particular, when plastic is used, the cost is reduced without sticking to the shape by injection molding or the like. If a metal is used for the support part 81, the support part can be processed precisely. Therefore, when the plastic 46b and the metal 46a are used for the support portion as shown in FIG. 26, a pulse detecting device with low cost and low noise can be obtained. In addition, when a porous material such as ceramics or sponge is used, since ultrasonic waves are not transmitted, noise is reduced and performance is improved.

(Example 17)
An embodiment of a pulse wave detection device 1 as an example of the ultrasonic diagnostic apparatus of the present invention will be described with reference to FIG. FIG. 27 is a side view of the measurement unit 4 related to the pulse wave detection device of the present embodiment, and the electrodes 60a and 60b and the wiring unit 61 are omitted. The same materials as those in Embodiment 1 were used for the band, stopper, processing section, piezoelectric element, and substrate.

  FIG. 27 is a diagram in which conductive rubber is disposed as the ultrasonic attenuation layer 73 between the electrodes 47a and 47b, the transmitting piezoelectric element 41, and the receiving piezoelectric element.

  The ultrasonic diagnostic apparatus of the present invention uses a frequency of about 1 MHz to 10 MHz as an ultrasonic wave to be used. Generally, an elastic material such as rubber has a high attenuation rate in the frequency band, and has an ultrasonic attenuation property. It can be used as a material. Therefore, as in the present embodiment, by placing conductive rubber between the electrodes 47a and 47b and the transmitting piezoelectric element 41 and the receiving piezoelectric element 42, the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are provided. A desired electric signal can be applied, and the possibility that ultrasonic waves are transmitted through the substrate 43 and directly received by the receiving piezoelectric element 42 can be reduced. As a result, the intensity of the ultrasonic wave transmitted into the living body is improved, so that the detection sensitivity can be improved.

  The ultrasonic wave 73 needs to be divided between the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 as shown in FIG. When not divided, the ultrasonic wave easily propagates from the transmitting piezoelectric element 41 to the receiving piezoelectric element 42 via the ultrasonic attenuation layer 73, resulting in a decrease in detection sensitivity.

(Example 18)
One embodiment of a pulse wave detection device 1 as an example of the ultrasonic diagnostic apparatus of the present invention will be described with reference to FIG. FIG. 28 is a side view of the measurement unit 4 related to the pulse wave detection device of the present embodiment. The materials for the band, processing section, stopper, piezoelectric element, and substrate were the same as those in the first embodiment. The electrodes 45a, 45b, 46a, 46b, 60a, 60b and the wiring part 61 are omitted.

  FIG. 28 is a diagram showing a configuration in which the transmitting piezoelectric element 41 and the receiving piezoelectric element 42 are arranged on a divided substrate 43 and the substrate is fixed to a support 81 via an ultrasonic attenuation layer 75.

  As the material of the ultrasonic attenuation layer 75, as described in the third embodiment, an epoxy resin containing tungsten powder, a porous material made of a porous material, and a conductive or insulating rubber described later are suitable. ing.

(Example 19)
One embodiment of a pulse wave detector 1 as an example of the ultrasonic diagnostic apparatus of the present invention will be described with reference to FIG. FIG. 29 is a side view of the measurement unit 4 related to the pulse wave detection device of the present embodiment. The materials for the band, processing section, stopper, piezoelectric element, and substrate were the same as those in the first embodiment. The electrodes 45a, 45b, 46a, 46b, 60a, 60b and the wiring part 61 are omitted.

  FIG. 29 is a diagram showing a configuration in which the support 81 and the substrate 43 are fixed via the ultrasonic attenuation layer 75. With the structure as shown in FIG. 29, the possibility that the ultrasonic wave is directly received by the receiving piezoelectric element 42 is further reduced, and as a result, the detection sensitivity can be improved.

(Example 20)
An embodiment of a pulse wave detection device 1 as an example of the ultrasonic diagnostic apparatus of the present invention will be described with reference to FIG. FIG. 30 is a side view of the measurement unit 4 related to the pulse wave detection device of the present embodiment. The materials for the band, processing section, stopper, piezoelectric element, and substrate were the same as those in the first embodiment. The electrodes 45a, 45b, 46a, 46b, 60a, 60b and the wiring part 61 are omitted.

  FIG. 30 is an explanatory diagram illustrating a configuration in which the attenuation layer 95 is provided between the divided substrates 43 in the measurement unit 4 in which the substrate 43 is divided and the support body 81 having the concave portions 82 is provided.

  When the measurement unit 4 is brought into contact with the skin at the time of measuring a pulse or the like, foreign matters such as sweat and dust are easily mixed between the divided substrates 43. At this time, if a foreign substance such as sweat or dust goes around the back surface 43b of the one surface 43a of the substrate 43, the ultrasonic wave generated from the transmitting piezoelectric element 41 through the foreign substance easily propagates directly to the receiving piezoelectric element 42. , Leading to a decrease in detection sensitivity.

  For this reason, if the attenuation layer 95 is provided between the divided substrates 43 as in the present embodiment, foreign matter is less likely to be mixed in, and detection sensitivity is not reduced.

  As the material of the attenuation layer 95, an acrylic or epoxy resin, on the contrary, the ultrasonic wave propagates through the resin. Therefore, it is desirable that the ultrasonic wave is difficult to propagate such as silicon rubber.

  In addition, the pulse detection apparatus shown in Examples 1 to 16 of the present invention can be used in an ultrasonic diagnostic apparatus as well. In addition, the ultrasonic diagnostic apparatus shown in Examples 17 to 20 can be used in the same manner for a pulse detection apparatus.

  In addition, by providing protrusions on the substrate, the transmitting piezoelectric element, or the receiving piezoelectric element, it is difficult for ultrasonic waves to propagate to the substrate, reducing pulse detection noise, and transmitting ultrasonic waves to the living body. It is possible to improve the reception intensity of the ultrasonic wave, which has the effect of improving the sensitivity of pulse detection.

  In addition, the resin layer provided on the substrate of the pulse detector allows the characteristics of the contact surface of the substrate with the living body to be optimally adjusted according to the application, and the resin layer is uniformly formed with an optimal thickness. Therefore, the pulse detection sensitivity can be further improved.

  In addition, by providing a transmitting piezoelectric element and a receiving piezoelectric element via a groove provided on the substrate, the receiving piezoelectric element does not directly receive the ultrasonic wave emitted by the transmitting piezoelectric element, thus reducing noise. And the reliability of the pulse detection device can be improved.

  Furthermore, by providing a support substrate for supporting the transmitting and receiving piezoelectric elements located on the substrate, the strength against external impact can be improved, and leakage of ultrasonic waves can be prevented.

  As described above, according to the pulse detecting device of the present invention, the transmitting piezoelectric element and the receiving piezoelectric element can be accurately arranged as designed on the transmission / reception substrate, so that the pulse detection hardly causes variations in quality. An apparatus can be provided, and pulse detection sensitivity can be improved.

  Furthermore, by controlling the acoustic impedance of the transmission / reception board or the thickness of the transmission / reception board, reflection of ultrasonic waves at the interface between the transmission / reception board and the living body can be reduced, and ultrasonic waves can be propagated efficiently.

  In addition, since the ultrasonic wave can be transmitted in one direction, the ultrasonic wave can efficiently propagate.

  Moreover, the characteristic of the contact surface with the biological body in a transmission / reception board | substrate can be optimally adjusted with the resin layer with which the transmission / reception board | substrate of the pulse detection apparatus was equipped according to the use.

  In addition, by using a silicon-based resin for the resin layer provided on the other side, the adhesion between the transmitting / receiving substrate and the living body is improved, so the air layer at the interface between the transmitting / receiving substrate and the living body is reduced, and the vibration of the ultrasonic waves Can be suppressed.

  In addition, since the transmitting piezoelectric element and the receiving piezoelectric element are provided via the groove provided in the transmitting / receiving substrate, the receiving piezoelectric element does not directly receive the ultrasonic wave generated by the transmitting piezoelectric element, so that noise is not generated. The reliability of the pulse detection device can be improved.

  Further, the other surface of the transmission / reception substrate is formed obliquely with respect to the one surface. That is, by making the other surface and one surface of the transmission / reception substrate not a parallel surface but a taper shape, the Doppler effect of blood flow is increased, and the pulse detection sensitivity can be improved.

  Furthermore, by providing a supporting substrate for supporting the transmitting piezoelectric element and the receiving piezoelectric element located on the transmitting / receiving substrate, the strength against an external impact can be improved and ultrasonic waves can be prevented.

  Further, the living body can grasp the pulse detection result by the display unit provided in the pulse detection device.

  Moreover, the pulse detecting device can be easily carried by providing a belt for mounting the pulse detecting device.

  In addition, the configuration in which the transmitting piezoelectric element or the receiving piezoelectric element and the transmission / reception substrate are joined by metal-to-metal bonding allows ultrasonic waves to propagate efficiently at the joining interface with little attenuation.

  As described above, according to the ultrasonic diagnostic apparatus of the present invention, the substrate and the piezoelectric element are fixed only by the power feeding unit, or the protrusion is provided on the substrate or the transmitting piezoelectric element or the receiving piezoelectric element to form a gap. By making the gap an ultrasonic attenuation layer or providing an ultrasonic attenuation layer such as a porous body, the ultrasonic wave is difficult to propagate from the transmitting piezoelectric element to the receiving piezoelectric element through the substrate. It is possible to efficiently transmit ultrasonic waves to the diagnosis site, and there is an effect that detection sensitivity can be improved. In addition, since the piezoelectric element is arranged on the substrate, the piezoelectric element can be placed with high accuracy, so that quality variations are unlikely to occur. In addition, by providing a support that supports the substrate, it is possible to improve strength against external impacts and handleability. In addition, by providing an ultrasonic attenuation layer between the support and the substrate, it is possible to efficiently transmit ultrasonic waves to the diagnosis site, and there is an effect of improving detection sensitivity.

  Further, by dividing the substrate and fixing it to the support, it becomes possible to efficiently transmit ultrasonic waves to the diagnostic site, and there is an effect of improving detection sensitivity.

  Also, by providing a member with ultrasonic attenuation such as rubber between the divided substrates, foreign matter such as sweat can be prevented from entering the back surface of the substrate and causing noise. This makes it possible to improve the detection stability.

  Furthermore, since the transmitting piezoelectric element and the receiving piezoelectric element can be accurately arranged on the substrate as designed, it is possible to provide an ultrasonic diagnostic apparatus that is less likely to cause variations in quality.

DESCRIPTION OF SYMBOLS 1 Pulse wave detection apparatus 2 Living body 2a Blood flow 3 Processing part 31 Processing calculating part 32 Drive circuit 33 Display part 4 Measuring part 5 Band 6 Fastening element 41 Transmission piezoelectric element 42 Reception piezoelectric element 45a, 45b, 46a, 46b Electrode 44 , 45 Transmission / reception substrate 44a One surface 44b One surface 45d One surface 43 Substrate 43a One surface 43c Groove 47a, 47b Electrode 50a Groove 49 Resin layer 61 Wiring 60a, 60b Electrode 62 Fixed portion 70 Gap 71 Bump 72 Protrusion 80 Gap 81 Support 81a Support body 82 Recessed part 83 Support column 89 Support body 95 Damping layer

Claims (14)

A piezoelectric element for transmission that transmits ultrasonic waves into the living body in accordance with the input drive signal;
A receiving piezoelectric element that receives the reflected wave reflected by the blood flow of the living body;
A substrate provided with the piezoelectric element for transmission and the piezoelectric element for reception;
A detector for detecting a pulse based on the ultrasonic wave transmitted by the transmitting piezoelectric element and the reflected wave;
The substrate is supported, and the support portion provided on the back surface of the surface of the substrate that faces the living body,
A separation portion in which at least a part of a surface of the substrate is separated;
Comprising the support and the gap formed by the substrate;
The transmitting piezoelectric element and the receiving piezoelectric element are disposed on the substrate with the spacing portion interposed therebetween,
The pulse wave detection device, wherein the gap is provided on a back surface of the substrate and is provided at a position facing the separation portion.     2. The transmitting piezoelectric element and the receiving piezoelectric element are fixedly mounted on separate substrates, respectively, and each of the substrates is configured on the same support portion. Pulse wave detector.     The pulse wave detection device according to claim 1, wherein the support portion is box-shaped.     The pulse wave detection device according to claim 1, wherein the support portion has a comb-teeth shape.     The pulse wave detection device according to any one of claims 1 to 4, wherein the support portion is ceramics.     The pulse wave detection device according to any one of claims 1 to 4, wherein the support portion is made of plastic.     The pulse wave detection device according to any one of claims 1 to 4, wherein the support portion is a metal.     The pulse wave detection device according to any one of claims 1 to 4, wherein the support portion is made of plastic and metal.     2. The pulse wave detection device according to claim 1, wherein the ultrasonic wave has a depth in the transmission / reception direction of the gap that is equal to or greater than a wavelength λ of the ultrasonic wave.     The pulse wave detection device according to any one of claims 1 to 9, wherein an area of the gap is larger than an area of an ultrasonic transmission / reception surface of the transmission piezoelectric element and the reception piezoelectric element.     11. The pulse wave detection device according to claim 1, wherein the transmitting piezoelectric element and the receiving piezoelectric element are provided in the gap portion. 11. The pulse wave according to any one of claims 1 to 11 , wherein an acoustic impedance of the substrate is between an acoustic impedance of the receiving piezoelectric element or the transmitting piezoelectric element and an acoustic impedance of a living body. Detection device. The pulse wave detection device according to any one of claims 1 to 12 , wherein the thickness of the substrate is about one-fourth of the wavelength of an ultrasonic wave generated by the transmitting piezoelectric element. An ultrasonic diagnostic apparatus comprising the pulse wave detection apparatus according to any one of claims 1 to 13 .

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