Flow channel built-in ultrasonic transducer

Abstract

To provide an ultrasonic vibrator having a flow path built in a vibration body, and a blood gas analysis device with the flow path built-in ultrasonic vibrator.SOLUTION: A flow path built-in ultrasonic vibrator includes: a vibration body having a flat circular bottom surface and a reflective surface located above the circular bottom surface and shrinking in diameter upward; and a circular plate-shaped piezoelectric element in contact with the bottom surface of the vibration body, provided with electrodes on its both surfaces, and having a thick vertical vibration mode, in which a processing flow path that penetrates the vibration body in an upper and lower direction along a center axis is provided in the center of the vibration body, ultrasonic waves are excited by applying an AC voltage of a predetermined frequency to the piezoelectric element, and the ultrasonic waves reflect on the reflective surface and head to the processing flow path.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an ultrasonic transducer that generates strong ultrasonic waves by focusing the ultrasonic waves, and more particularly to an ultrasonic transducer that incorporates a flow path through which an object passes. [Background technology]

[0002] 2. Description of the Related Art Ultrasonic waves have been used in various fields such as manufacturing, civil engineering, agriculture, forestry, fisheries, food, pharmaceuticals, and medicine, and Langevin type transducers are widely used as ultrasonic transducers. As shown in Patent Document 1, the Langevin transducer is composed of a ring-shaped piezoelectric element and an electrode sandwiched between two metal blocks, and the two metal blocks are fastened and fixed with a through bolt, and an AC voltage is applied to the piezoelectric element via the electrodes to excite minute vibrations, and ultrasonic waves are generated by increasing the amplitude by utilizing the resonant vibration in the longitudinal direction of the transducer. This Langevin transducer is used in many fields as a robust and high-output transducer, but the Langevin transducer has problems in that it can only obtain an output in a uniform frequency range depending on the length, material type, and shape of the metal block, and cannot be miniaturized, and therefore has limitations on its applications and functional expansion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-29758 A [Patent Document 2] Kang CHEN, Takasuke IRIE, Takashi IIJIMA and Takeshi MORITA, "Double-parabolic-reflectors acoustic waveguides for high-power medical ultrasound", Scientific Reports, vol. 9, 18493, 2019 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to solve the above problems, the inventors have developed a high-power ultrasonic transducer that includes a cylindrical vibrator having a first paraboloid of revolution at its top, a hemispherical convex portion that forms a second paraboloid of revolution protruding downward at the center of the bottom of the vibrator, a thin rod waveguide that extends in the opposite direction to the convex portion along the central axis of the vibrator, and reflects ultrasonic vibrations from the piezoelectric element in two stages at the first and second paraboloids of revolution, converts the ultrasonic vibrations into plane waves at the second paraboloid of revolution and focuses them on the thin rod waveguide, and outputs high-power ultrasonic waves from the tip of the thin rod waveguide (see Patent Document 2). This high-power ultrasonic transducer allows the device to be miniaturized and enables high-power ultrasonic waves to be output from the tip of the thin rod. After developing the above-mentioned high-power ultrasonic transducer, the inventors continued their research and came to invent an ultrasonic transducer with built-in flow channel that can apply high-power ultrasonic waves to a target object from within the transducer, rather than outputting high-power ultrasonic waves from the transducer to the outside. Furthermore, the inventors have focused on the application of the flow path built-in ultrasonic transducer to the crushing of blood cells in blood, and have invented a blood gas analyzer equipped with a flow path built-in ultrasonic transducer. An object of the present invention is to provide an ultrasonic transducer having a built-in flow path inside the transducer body, and a blood gas analyzer including the built-in flow path ultrasonic transducer. [Means for solving the problem]

[0005] In order to achieve the above-mentioned object, the flow-path-integrated ultrasonic transducer of the present invention comprises a vibrating body having a flat circular bottom surface and a reflecting surface located above the circular bottom surface and tapering in an upward direction, and a circular plate-shaped piezoelectric element having a thickness-extensional vibration mode in contact with the bottom surface of the vibrating body and having electrodes on both sides, a processing flow path is provided at the center of the vibrating body, which passes through the vibrating body in the vertical direction along the central axis, and ultrasonic waves are excited by applying an AC voltage of a predetermined frequency to the piezoelectric element, and the ultrasonic waves are reflected by the reflecting surface and directed toward the processing flow path. The reflective surface may be a paraboloid of revolution, the shape of which may be such that the focus point of ultrasound reflected thereby is located at a wall of the flow path, beyond the process flow path, or within the process flow path. The reflective surface may also comprise a conical surface, in which case ultrasonic waves reflected thereby may be focused at multiple points along the process flow path. Furthermore, the vibrating body may be made of an aluminum alloy, a titanium alloy, brass or stainless steel. Furthermore, the vibrating body can be configured to have an upper connector mounting hole and a lower connector mounting hole spaced apart from each other and facing each other along the central axis at its upper and lower central parts, as well as a through hole formed along the central axis between the upper connector mounting hole and the lower connector mounting hole, and the through hole can be configured to function as the processing flow path. In this case, the ultrasonic transducer may further have an upper connector and a lower connector that can be attached to the upper connector mounting hole and the lower connector mounting hole, and each connector may have a through hole formed along its central axis, and when the upper connector and the lower connector are attached to the upper connector mounting hole and the lower connector mounting hole, the through hole of the connector and the through hole of the vibrator communicate with each other to form a single flow path. Furthermore, in this case, a connection part may be formed at one end of the upper connector and the lower connector to which a tube or pipe that constitutes a supply circuit for a treatment object such as blood can be connected. The vibrating body may have a radially outwardly extending annular flange at its base. In addition, the flow-path-integrated ultrasonic transducer of the present invention comprises a vibrating body having a flat circular bottom surface and a reflecting surface located above the circular bottom surface and tapering in an upward direction, and a circular plate-shaped piezoelectric element having a thickness-extending vibration mode in contact with the bottom surface of the vibrating body and electrodes on both sides, and is characterized in that two flow-path-integrated ultrasonic transducer pieces having a processing flow path that passes through the vibrating body in the vertical direction along the central axis at the center of the vibrating body are stacked one on top of the other so that the piezoelectric elements face each other and the processing flow paths are connected, and ultrasonic waves are excited by applying an AC voltage of a predetermined frequency to each piezoelectric element, and the ultrasonic waves are reflected by each reflecting surface and directed toward the processing flow path. Furthermore, a blood gas analyzer equipped with an ultrasonic transducer with built-in flow path according to the present invention comprises a syringe mounting section to which a syringe containing blood can be attached, a suction nozzle which enters the inside of the syringe attached to the syringe mounting section and suctions the blood inside the syringe, a suction pump connected to the suction nozzle, a sensor for analyzing the components of the blood suctioned by the suction nozzle, a blood flow path leading from the suction nozzle via the sensor to a waste liquid section, and a control device which controls the operation of at least the suction pump, and is characterized in that the ultrasonic transducer with built-in flow path is disposed so that its flow path communicates with the blood flow path. Effect of the Invention

[0006] The flow path built-in ultrasonic transducer according to the present invention comprises a vibration body having a flat circular bottom surface and a reflecting surface located above the circular bottom surface and tapering toward the top, and a circular plate-shaped piezoelectric element having a thickness longitudinal vibration mode in contact with the bottom surface of the vibration body and having electrodes on both sides, and a processing flow path is provided at the center of the vibration body along the central axis line, and ultrasonic waves are excited by applying an AC voltage of a predetermined frequency to the piezoelectric element, and the ultrasonic waves are reflected at the reflecting surface and directed toward the processing flow path, so that the reflected ultrasonic waves are focused on the processing flow path formed inside the vibration body or near the processing flow path, and it is possible to obtain strong ultrasonic waves in the processing flow path. In this way, the flow path built-in ultrasonic transducer according to the present invention obtains strong ultrasonic waves by focusing ultrasonic waves using the reflection of ultrasonic waves at the reflecting surface, so that the vibration body can be made small, and as a result, the entire ultrasonic transducer can be made small. In addition, according to the ultrasonic transducer with built-in flow path of the present invention, the ultrasonic wave is focused by utilizing the reflection of the ultrasonic wave on the reflection surface to obtain a strong ultrasonic wave, so that the resonance frequency does not depend on the length of the vibrator as in the Langevin transducer, and therefore it is possible to obtain a strong ultrasonic wave in a wide band in the processing flow path by adjusting the frequency of the AC voltage applied to the piezoelectric element. Furthermore, it is also possible to adjust the waveform of the strong ultrasonic wave obtained in the processing flow path by adjusting the waveform of the AC voltage applied to the piezoelectric element or by synthesizing the waveform, so that it is possible to obtain a strong ultrasonic wave suited to various applications. Furthermore, a processing flow path passing through the inside of the vibrator is provided, and the ultrasonic wave is focused in the processing flow path or in the vicinity of the processing flow path inside the vibrator, so that it is possible to irradiate the processing object with a strong ultrasonic wave inside the ultrasonic transducer by passing the processing object through the processing flow path. By forming the reflecting surface in a paraboloid of revolution shape, a focal point can be provided on the wall surface of the processing flow path or within the processing flow path, making it possible to obtain strong ultrasonic waves at the focal point. Furthermore, by forming the reflecting surface into a paraboloid of revolution whose focal point is located beyond the processing flow path, it is possible to obtain strong ultrasonic waves over a wide range of the processing flow path. Furthermore, by forming the reflecting surface into a conical shape, the reflected ultrasonic waves are focused at a plurality of points along the treatment flow path, making it possible to obtain strong ultrasonic waves over an even wider range of the treatment flow path. In addition, the flow-path-integrated ultrasonic transducer of the present invention comprises a vibrating body having a flat circular bottom surface and a reflecting surface located above the circular bottom surface and tapering in an upward direction, and a circular plate-shaped piezoelectric element having a thickness-longitudinal vibration mode that is in contact with the bottom surface of the vibrating body and has electrodes on both sides. Two flow-path-integrated ultrasonic transducer pieces are arranged one above the other so that the piezoelectric elements face each other and the processing flow paths are connected, and an AC voltage of a predetermined frequency is applied to each piezoelectric element to excite ultrasonic waves, and the ultrasonic waves are reflected by each reflecting surface and directed toward the processing flow path, so that the processing flow path can be lengthened and the range in which powerful ultrasonic waves can be obtained can be expanded. In this case, by making the reflecting surface into a conical shape, ultrasonic waves are focused at multiple points along the long processing flow path, making it possible to obtain powerful ultrasonic waves over twice the range of a flow-path-integrated ultrasonic transducer composed of a single flow-path-integrated ultrasonic transducer piece. Furthermore, by making the reflecting surface into a rotating radiation surface shape and making its focus point the vertical center point of the processing flow path in a pair of flow-path-integrated ultrasonic transducer pieces, the ultrasonic waves excited by the piezoelectric element of one of the transducer pieces can be reflected by the reflecting surface, pass through the focus point, and then be reflected by the reflecting surface of the other transducer piece and returned to the piezoelectric element of the other transducer piece, thereby making it possible to form a resonant system and more efficiently obtain powerful ultrasonic waves at a constant voltage. A blood gas analyzer equipped with an ultrasonic transducer with built-in flow path according to the present invention includes a syringe mounting section to which a syringe with blood can be attached, a suction nozzle that enters the inside of the syringe mounted on the syringe mounting section to suction the blood inside the syringe, a suction pump connected to the suction nozzle, a sensor for analyzing the components of the blood suctioned by the suction nozzle, a blood flow path that connects the suction nozzle to a waste liquid section via the sensor, and a control device for controlling the operation of at least the suction pump. Since the ultrasonic transducer with built-in flow path is provided so that its flow path communicates with the blood flow path, it is possible to suction blood from the syringe without hemolyzing the blood in advance and hemolyze the blood in the analyzer. This makes it possible, for example, to hemolyze blood using the ultrasonic transducer with built-in flow path when measuring hemoglobin and send it to the sensor, and to send non-hemolyzed blood to the sensor when measuring other components without operating the ultrasonic transducer with built-in flow path. It is also possible to provide two flow paths in the blood gas analyzer and provide an ultrasonic transducer with built-in flow path in one of the flow paths. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic side view of an embodiment of a flow channel-integrated ultrasonic transducer according to the present invention; [Diagram 2] 2 is an exploded vertical cross-sectional view of the ultrasonic transducer shown in FIG. 1. [Diagram 3] 2 is a central longitudinal sectional view of the assembled ultrasonic transducer shown in FIG. 1. [Figure 4] 2 is a diagram showing a propagation state of ultrasonic waves in the ultrasonic transducer shown in FIG. 1. [Diagram 5] 11A and 11B are diagrams showing the propagation state of ultrasonic waves in a second embodiment of a flow-path-integrated ultrasonic transducer according to the present invention. [Figure 6] 13A to 13C are diagrams showing the propagation state of ultrasonic waves in a third embodiment of a flow channel-integrated ultrasonic transducer according to the present invention. [Figure 7] 13A to 13C are diagrams showing the propagation state of ultrasonic waves in a fourth embodiment of a flow-path-integrated ultrasonic transducer according to the present invention. [Figure 8]1A to 1C are diagrams showing the propagation state of ultrasonic waves in one embodiment of a flow-path built-in ultrasonic transducer having a pair of ultrasonic transducer pieces according to the present invention. [Figure 9] 11A and 11B are diagrams showing the propagation state of ultrasonic waves in a second embodiment of a flow-path built-in ultrasonic transducer having a pair of ultrasonic transducer pieces according to the present invention. [Figure 10] 1 is a schematic external view of a blood gas analyzer equipped with a built-in ultrasonic transducer according to the present invention. FIG. [Figure 11] FIG. 11 is a schematic diagram of the internal mechanism of the blood gas analyzer shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of a flow path built-in ultrasonic transducer and a blood gas analyzer including the flow path built-in ultrasonic transducer according to the present invention will be described with reference to several embodiments shown in the accompanying drawings. First, a first embodiment of a flow channel built-in ultrasonic transducer (hereinafter simply referred to as an "ultrasonic transducer") according to the present invention will be described. FIG. 1 is a schematic side view of an ultrasonic transducer, FIG. 2 is an exploded central vertical sectional view of the ultrasonic transducer shown in FIG. 1, and FIG. 3 is an assembled central vertical sectional view of the ultrasonic transducer shown in FIG. In the drawing, reference numeral 1 denotes the entire ultrasonic transducer, and this ultrasonic transducer 1 includes a vibrating body 2, a piezoelectric element 3, an upper connector 4, and a lower connector 5. The vibrating body 2 is made of a cylindrical body formed in a hemispherical shape with a paraboloid of revolution 2a at its upper part as a reflecting surface, and a circular plate-shaped piezoelectric element 3 is fixed to its bottom surface 2b. The vibrating body 2 has, at its central upper and lower parts, connector mounting holes 2c and 2d that are spaced apart from each other and extend along the central axis of the vibrating body 2 for mounting an upper connector 4 and a lower connector 5, and a through hole 2e that constitutes a flow path according to the present invention and extends along the central axis of the vibrating body is formed between the connector mounting holes 2c and 2d. The vibrating body 2 is formed of a material that is advantageous for the propagation of ultrasonic vibration excited by the piezoelectric element 3, such as an aluminum alloy, a titanium alloy, brass, or stainless steel. The material of the vibrating body 2 is not limited to an aluminum alloy, but may be any material that is advantageous for the propagation of ultrasonic vibration excited by the piezoelectric element 3. The reference symbol 2f indicates a flange formed on the lower part of the vibrating body 2 and extending radially outward, and the vibrating body 2 is fixed to any structure via this flange 2f. The piezoelectric element 3 is in the form of a circular ring plate having an inner diameter larger than the diameter of the lower connector mounting hole 2d, is made of piezoelectric ceramics having electrodes (not shown) on both sides, and has a thickness longitudinal vibration mode. The piezoelectric element 3 is fixed to the bottom surface of the vibrating body 2 by adhesive or the like, and excites ultrasonic waves by applying an AC voltage at a predetermined frequency via a control device (not shown). The upper connector 4 and the lower connector 5 each have mounting parts 4a and 5a at one end that are formed so as to be mountable to the connector mounting holes 2c and 2d, and at the other end are formed connection parts 4b and 5b to which a pipe or tube for carrying the material to be treated can be connected. The upper connector 4 and the lower connector 5 each have through holes 4c and 5c that extend along their central axes, and when the upper connector 4 and the lower connector 5 are mounted to the vibrating body 2, the through holes 4c and 5c of the upper connector 4 and the lower connector 5 communicate with the through hole 2d formed in the vibrating body 2 to form a single flow path. In this embodiment, the paraboloid of revolution 2a of the vibrating body 2 in the ultrasonic transducer 1 configured as described above focuses the ultrasonic waves excited by the piezoelectric element 3 onto a focus point P on any wall surface of the through hole 2e of the vibrating body 2 that forms the flow path. According to the ultrasonic transducer 1 configured as described above, an AC voltage is applied to the piezoelectric element 3 at a predetermined frequency via a control device (not shown) to excite ultrasonic waves parallel to the paraboloid of revolution 2a from the piezoelectric element 3, and the ultrasonic waves excited by the piezoelectric element 3 are reflected by the paraboloid of revolution 2a and focused at the focus point P, whereby a strong ultrasonic wave is obtained at the focus point P, and as a result, a strong sound wave is generated inside the processing flow path formed by the through-hole 2e (see FIG. 4). Note that FIGS. 1 to 4 are schematic diagrams for explaining the configuration of the ultrasonic transducer, and the shape of the paraboloid of revolution is not accurately depicted. The dimensions of the vibrating body 2 in the ultrasonic transducer 1 are a diameter of 40 mm and a height of 10 mm, and the material is an aluminum alloy (duralumin), and the dimensions of the piezoelectric element 3 are an inner diameter of 16 mm, an outer diameter of 40 mm, and a thickness of 1.1 mm. It was confirmed that by applying an AC voltage of 80 Vpp to the piezoelectric element 3 of the ultrasonic transducer 1 configured in this manner, a strong ultrasonic wave with a frequency of 1.2 MHz was obtained in the processing flow path. The dimensions of the vibrating body 2 and the piezoelectric element 3 are not limited to those in the above-mentioned embodiments. For example, the diameter of the vibrating body 2 may be 10 mm to 80 mm, the height may be 10 mm to 30 mm, and the inner diameter of the piezoelectric element 13 may be 5 mm to 30 mm, and the thickness may be 0.1 mm to 5 mm. Furthermore, the voltage applied to the piezoelectric element 3 may be an AC voltage having a frequency of 20 kHz to 20 MHz, and the frequency of the ultrasonic waves obtained at the focus point P may be 10 KHz to 20 MHz.

[0009] According to the ultrasonic transducer 1 configured as described above, the ultrasonic waves excited in the piezoelectric element 3 are focused using the paraboloid of revolution 2a to obtain powerful ultrasonic waves in the processing flow path, so that it is possible to miniaturize the vibrating body 2 and therefore the entire ultrasonic transducer 1. In addition, since the resonance frequency does not depend on the length of the vibrating body, as in the Langevin transducer, it is possible to obtain a wide band of powerful ultrasonic waves at the focus point P by adjusting the frequency of the AC voltage applied to the piezoelectric element 3. Furthermore, it is also possible to adjust the waveform of the powerful ultrasonic waves obtained at the focus point P by adjusting the waveform of the AC voltage applied to the piezoelectric element 3 or by synthesizing the waveforms, and thus it is possible to obtain powerful ultrasonic waves suited to various applications. Furthermore, a processing flow path passing through the inside of the vibrator 2 is provided, and a focus point P is provided in the processing flow path inside the vibrator 2, so that the processing object can be irradiated with strong ultrasonic waves inside the ultrasonic transducer 1 by flowing the processing object through the processing flow path. As a result, for example, by interposing the ultrasonic transducer 1 in a flow path through which blood flows, such as in a blood gas analyzer, the ultrasonic transducer 1 can be used for applications such as disintegrating blood cells in the blood flowing through the flow path using ultrasonic waves. Note that the application of the ultrasonic transducer 1 according to the present invention is not limited to blood gas analyzers, and can be applied to any device that flows the processing object through a processing flow path, and specifically, for example, it can be applied to a device that decomposes, disinfects, or sterilizes dioxins, an emulsification device, or a chemical reaction device that uses cavitation. Furthermore, the configuration for connecting the upper connector 4 and the lower connector 5 to the vibrating body 2 is not limited to this embodiment, and for example, the upper connector 4 and the lower connector 5 may be configured to be connected outside the radiation surface 2a and the bottom surface 2b of the vibrating body 2. In this way, the length of the flow path inside the vibrating body 2 can be secured to be long, so that the range of options for the position of the focus point P is expanded, and the options for the shape of the vibrating body 2 are expanded. Furthermore, the position of the focus point P is not limited to this embodiment, but can be any position that can generate strong sound waves in the processing flow path, and the focus point P does not necessarily have to be a single point. For example, by making the reflecting surface a conical surface rather than a paraboloid of revolution, it becomes possible to arrange multiple focus points P along the processing flow path.

[0010] 5 is a diagram showing the propagation state of ultrasonic waves in a second embodiment of the flow channel-integrated ultrasonic transducer according to the present invention. In this embodiment, the only difference from the first embodiment is the position of the focus point P, and the other configurations are the same as those of the ultrasonic transducer shown in the first embodiment, so that the same reference numerals as those in the first embodiment are given to the corresponding components and the duplicated explanations are omitted. As shown in the drawing, in this embodiment, the focus point P is located beyond the through-hole 2e that constitutes the processing flow path. In this manner, by configuring the focus point P so that it is focused at a position beyond the processing flow path after being reflected by the paraboloid of revolution 2a, it becomes possible to obtain powerful ultrasonic waves over a wide range of the processing flow path. Incidentally, the paraboloid of revolution in FIG. 5 is drawn to have the same shape as the paraboloid of revolution shown in FIG. 1, but FIG. 5 is a schematic diagram showing the configuration of an ultrasonic transducer according to the present invention, and the shape of the paraboloid of revolution is drawn only briefly. In reality, it goes without saying that the shape of the paraboloid of revolution in the second embodiment is different from that of the paraboloid of revolution in the first embodiment.

[0011] 6 is a diagram showing the propagation state of ultrasonic waves in a third embodiment of the flow channel type ultrasonic transducer according to the present invention. In this embodiment, the position of the focus point P is different from that of the first embodiment, and the other configurations are the same as those of the ultrasonic transducer shown in the first embodiment, so that the same reference numerals as those of the first embodiment are given to the corresponding components and the duplicated explanations are omitted. As shown in the drawing, in this embodiment, the focus point P is located at the center of a through-hole 2e that constitutes the processing flow path. In this way, by configuring the focal point P so that it is focused at the center of the processing flow path after being reflected by the paraboloid of revolution 2a, it becomes possible to obtain a strong ultrasonic wave within the processing flow path. Incidentally, the paraboloid of revolution in FIG. 6 is drawn to have the same shape as the paraboloid of revolution shown in FIG. 1 and FIG. 5, but FIG. 6 is a schematic diagram showing the configuration of an ultrasonic transducer according to the present invention, and the shape of the paraboloid of revolution is drawn only briefly. In reality, it goes without saying that the shape of the paraboloid of revolution in the third embodiment is different from that of the paraboloid of revolution in the first and second embodiments.

[0012] In the above embodiment, the reflecting surface is configured as a paraboloid of revolution, but the shape of the reflecting surface is not limited to that of this embodiment, and may be, for example, a conical shape. FIG. 7 is a diagram showing the propagation state of ultrasonic waves in a fourth embodiment of a flow-path built-in ultrasonic transducer according to the present invention. In this embodiment, the structure is the same as that of the first embodiment except that the vibrating body is conical, so the same reference numerals are used for the components corresponding to those of the first embodiment and duplicated explanations will be omitted. As shown in the drawing, the transducer 2 of the ultrasonic transducer according to this embodiment is cone-shaped, a piezoelectric element 3 is provided on its bottom surface 2b, and the reflecting surface is constituted by a conical surface 2a. According to the ultrasonic transducer configured as described above, an AC voltage is applied to the piezoelectric element 3 at a predetermined frequency via a control device (not shown) to excite ultrasonic waves from the piezoelectric element 3 in parallel toward the conical surface 2a, and the ultrasonic waves excited by the piezoelectric element 3 are reflected by the conical surface 2a and directed toward the through-hole 2e that constitutes the processing flow path. As a result, as shown in FIG. 7, the ultrasonic waves are focused at multiple points along the processing flow path, generating powerful sound waves over a wide range inside the processing flow path. By configuring in this way, the range in which powerful sound waves are generated in the processing flow path of the ultrasonic transducer can be expanded, and as a result, the processing range in the processing flow path can be expanded.

[0013] Next, referring to FIG. 8, the configuration of the flow-path-integrated ultrasonic transducer of the present invention will be described, which is configured by arranging two pairs of ultrasonic transducer pieces 10 and 20, each having the same configuration as the ultrasonic transducer 1 configured as described above, one above the other with the piezoelectric elements 13 and 23 facing each other. In the figure, reference numerals 10 and 20 denote ultrasonic transducer pieces. Each of the ultrasonic transducer pieces 10 and 20 has a vibrating body 12 and 22, and an annular piezoelectric element 13 and 23 having electrodes (not shown) on both sides is fixed to the bottom surface of the vibrating body 12 and 22. Each of the vibrating bodies 12 and 22 has a truncated cone shape and has a conical surface 12a and 22a as a reflecting surface. Each of the vibration bodies 12 and 22 has a cylindrical connecting flange 12b or 22b that protrudes outward in the axial direction from its bottom surface and has a size that allows them to be fitted together. Furthermore, each of the vibration bodies 12 and 22 has a through hole 12c or 22c formed along its central axis, and when the vibration bodies 12 and 22 are joined, the through holes 12c or 22c communicate with each other to form a processing passage. In the drawing, reference numerals 12d and 22d denote flanges projecting radially outward, reference numeral 14 denotes an upper connector, and reference numeral 24 denotes a lower connector. The two ultrasonic transducer pieces 10 and 20 constructed as described above are arranged one above the other and joined together so that the piezoelectric elements 13 and 23 face each other, and when joined, the connecting flanges 12b and 22 fit together to form a flow path-integrated ultrasonic transducer. According to the above-mentioned flow path built-in ultrasonic transducer, an AC voltage is applied to each piezoelectric element 13 and 23 at a predetermined frequency via a control device (not shown), so that ultrasonic waves are excited from the piezoelectric elements 13 and 23 in parallel toward the conical surfaces 12a and 22a as reflecting surfaces, and the ultrasonic waves excited by the piezoelectric elements 13 and 23 are reflected by the conical surfaces 12a and 22a and focused on the through holes 12c and 22c that constitute the processing flow path, thereby obtaining strong ultrasonic waves in the processing flow path. Note that FIG. 8 is a schematic diagram for explaining the configuration of the ultrasonic transducer, and the shape of the conical surface is not accurately depicted. In this way, by arranging two ultrasonic transducer pieces 10 and 20 having conical surfaces as reflecting surfaces one on top of the other so that their through holes 12c and 22c are connected to form a single processing flow path, the range of the processing flow path through which powerful ultrasonic waves can be obtained can be expanded. Specifically, the range of the processing flow path through which powerful ultrasonic waves can be obtained can be doubled compared to the range of the embodiment shown in FIG. 7. In addition, by arranging the ultrasonic transducer pieces in two stacked ones on top of each other in this manner, the sound waves spread (diffuse) during the focusing process, making it possible to focus ultrasonic waves particularly efficiently in the center of the entire ultrasonic transducer, making it possible to reduce the diameter of the vibrating body and piezoelectric element.

[0014] Further, with reference to FIG. 9, another embodiment of a built-in flow path type ultrasonic transducer having a pair of ultrasonic transducer pieces will be described. The configuration of each ultrasonic transducer piece in this embodiment has the same structure as that of the embodiment shown in FIG. 8 except for the shape of the transducer body, so corresponding components are given the same reference numerals and duplicated explanations are omitted. In this embodiment, the vibrating bodies 12 and 22 of the ultrasonic transducer pieces 10 and 20 are cylindrical bodies having paraboloids of revolution 12a and 22a on the upper part, respectively, and the paraboloids of revolution 12a and 22a are each formed so that their focus points P are located at the center point of the entire ultrasonic transducer, i.e., the center of the processing flow path formed by connecting holes 12c and 22c. According to the ultrasonic transducer configured as described above, ultrasonic waves output from the piezoelectric element 13 of one ultrasonic transducer piece 10 are reflected by the paraboloid of revolution 12a of that ultrasonic transducer piece 10, pass through the focus point P, and then are reflected by the paraboloid of revolution 22a of the other ultrasonic transducer piece 20 and return to the piezoelectric element 23 of the ultrasonic transducer piece 20, thereby forming a resonant system and making it possible to generate powerful ultrasonic waves at the focus point P more efficiently at a constant voltage.

[0015] Next, an embodiment of a blood gas analyzer including a flow path built-in ultrasonic transducer according to the present invention will be described with reference to Figs. FIG. 10 is a perspective view of one embodiment of a blood gas analyzer, and FIG. 11 is a schematic diagram showing the internal mechanism of the blood gas analyzer shown in FIG. In the figure, reference numeral 30 denotes the entire blood gas analyzer, reference numeral 31 denotes a casing of the blood gas analyzer 30, reference numeral 32 denotes a monitor which also functions as an operation panel, and reference numeral 33 denotes a printer for printing out the analysis results. A calibration liquid tank 35, a cleaning liquid tank 36 and a waste liquid tank 37 are detachably attached to the front surface of the casing 31. A syringe mounting portion 38 for mounting a syringe S is provided on the front upper surface of the casing 31. A syringe detection sensor 38a for detecting whether or not the syringe S is mounted is provided on the syringe mounting portion 38 (see FIG. 6). As shown in FIG. 11, the inside of the casing 31 is provided with: A suction nozzle 40 configured to be able to be inserted into and removed from the syringe S attached to the attachment portion 38; An actuator 41 for moving the suction nozzle 40; A suction circuit 42 connected to the suction nozzle 40; A pump 43 that generates a suction force in the suction nozzle 40 through the suction circuit 42; a flow sensor 44 arranged upstream of the pump 43 in the suction circuit 42; A flow path built-in ultrasonic transducer 45 disposed between the pump 43 and the flow sensor 44 in the suction circuit 42; an analytical sensor unit 46 disposed between the flow path built-in ultrasonic transducer 45 and the pump 43 in the suction circuit 42; A control device 47 for controlling each of the above-mentioned parts; is provided. 10 and 11, reference numeral 50 denotes a suction nozzle housing portion that houses the suction nozzle 40 so that the suction nozzle 40 can be moved into and out of the syringe S. As shown in FIG. 11, the suction nozzle 40 has a tip portion 40a having a diameter large enough to enter at least the inside of the syringe S, and a body portion 40b connected to the tip portion 40a and having a diameter smaller than that of at least the tip portion 40a. In the suction nozzle housing 50, a first valve 51 and a second valve 52 that can be closed by the tip 40a of the suction nozzle 40 are arranged at an interval along the moving direction of the suction nozzle 40. Between the two valves 51 and 52 in the suction nozzle housing 50, a cleaning liquid inlet 53 and a waste liquid outlet 54 are provided. When cleaning the suction nozzle 40 and the suction circuit 42, the tip 40a of the suction nozzle 40 is moved to a position where the first valve 51 and the second valve 52 are closed, and then a cleaning liquid is supplied from the cleaning liquid tank 36 to the space between the first valve 51 and the second valve 52 in the suction nozzle housing 50 through the cleaning liquid inlet 53 by a pump (or pump 43) not shown in the figure, the cleaning liquid is sucked by the suction nozzle 40 through the pump 43, and the cleaning liquid flows through the flow sensor 44, the ultrasonic vibrator 45, and the analytical sensor unit 46, and is discharged into the waste liquid tank 37. After cleaning, the cleaning liquid that has not been sucked by the suction nozzle 40 is discharged into the waste liquid tank 37 via the waste liquid port 54 by a pump (not shown) (or pump 43). The control device 47 receives signals from the syringe detection sensor 38a and the flow sensor 44, and controls the operations of the actuator 41 and the pump 43 based on these signals. Furthermore, the control device 47 performs blood component analysis based on the detection signal from the analytical sensor unit 46, and outputs the analysis results to the monitor 32 and the printer 33. The blood component analysis process based on the detection signal from the analytical sensor unit 46 is similar to that of known blood component analyzers, and therefore a detailed description thereof will be omitted in this specification. Furthermore, the control device 47 controls the operation of the flow path built-in ultrasonic transducer 45 based on signals from the syringe detection sensor 38 a and the flow sensor 44 . The configuration of the built-in flow path ultrasonic transducer 45 is the same as the structure of the built-in flow path ultrasonic transducer 1 described based on Figures 1 to 4, so here, the same symbols are used to describe the components corresponding to the embodiments of Figures 1 to 4. The flow path built-in ultrasonic transducer 45 is provided such that the suction circuit 42 is connected to the connection part 4b of the upper connector 4 and the connection part 5b of the lower connector 5, and blood flowing through the suction circuit 42 flows through the flow path of the flow path built-in ultrasonic transducer 45. When blood passes through the treatment flow path in the flow path built-in ultrasonic transducer 45 based on signals from the syringe detection sensor 38a and the flow sensor 44, the control device 47 applies an AC voltage of a predetermined frequency to the piezoelectric element 3 to excite ultrasonic waves, generating strong ultrasonic waves in the treatment flow path, and the strong ultrasonic waves destroy red blood cells in the blood to hemolyze the blood. In this embodiment, the dimensions of the vibrator 2 in the ultrasonic vibrator 25 are a diameter of 40 mm, a height of 10 mm, and the material is an aluminum alloy (duralumin), and the dimensions of the piezoelectric element 3 are an inner diameter of 16 mm, an outer diameter of 40 mm, and a thickness of 1.1 mm. Furthermore, the AC voltage applied to the piezoelectric element 3 by the control device 47 is 80 Vpp, the frequency of the high-intensity ultrasonic waves obtained in the processing flow path is 1.2 MHz, and it was confirmed that the high-intensity ultrasonic waves can destroy red blood cells in the blood. According to a blood gas analyzer equipped with an ultrasonic transducer with built-in flow path as described above, by providing the ultrasonic transducer with built-in flow path in the suction circuit of the blood gas analyzer, it is possible to suction blood from the syringe S without hemolyzing the blood beforehand and hemolyze the blood within the analyzer. This makes it possible to hemolyze blood using the ultrasonic transducer with built-in flow path as necessary when measuring hemoglobin and send it to analytical sensor unit 46, and to send non-hemolyzed blood to analytical sensor unit 46 without operating the ultrasonic transducer with built-in flow path when measuring other components. In the above embodiment, the voltage applied to the piezoelectric element 3 of the flow path built-in ultrasonic transducer 45 can be changed by the control device 47 to change the powerful ultrasonic waves obtained in the processing flow path, thereby enabling the ultrasonic cleaning function to be exerted in the processing flow path. In the above embodiment, the flow-path-integrated ultrasonic vibrator 45 is provided in one suction circuit 42, but this configuration is not limited to this embodiment. For example, the suction circuit 42 may be provided with two branched circuits, one of which may be provided with a hemoglobin measuring sensor and the other may be provided with a sensor for measuring a substance other than hemoglobin, and the flow-path-integrated ultrasonic vibrator 45 may be provided only in the circuit in which the hemoglobin measuring sensor is provided. Furthermore, in the above-mentioned embodiment, the blood gas analyzer is provided with an ultrasonic transducer with built-in flow path shown in Figs. 1 to 4, but this configuration is not limited to this embodiment, and it is of course possible to provide the ultrasonic transducer with built-in flow path shown in Figs. 5 to 9 in the suction circuit. [Explanation of symbols]

[0016] 1 Ultrasonic transducer 2. Vibration body 2a Paraboloid of revolution 2b Bottom 2c Upper connector mounting hole 2d Lower connector mounting hole 2e Through hole (processing flow path) 2f flange 2' Vibration body (fourth embodiment) 2a' Conical surface (fourth embodiment) 3. Piezoelectric element 4 Upper connector 4a Mounting part 4b Connection 4c through hole 5 Lower connector 5a Mounting part 5b Connection 5c through hole P Focus point 10 Ultrasonic transducer piece 12 Vibration body 12a Conical surface (embodiment of FIG. 8); Paraboloid of revolution (embodiment of FIG. 9) 12b Connecting flange 12c through hole 12d flange 13 Piezoelectric element 14 Upper connector 20 Ultrasonic transducer piece 22 Vibration body 22a Conical surface (embodiment of FIG. 8); Paraboloid of revolution (embodiment of FIG. 9) 22b Connecting flange 22c through hole 22d flange 23 Piezoelectric element 24 Lower connector P Focus point 30 Blood gas analyzer 31 Casing 32 Operation Panel 33 Printer 35 Calibration solution tank 36 Cleaning solution tank 37 Waste liquid tank 38 Syringe attachment part 38a Syringe detection sensor 40 Suction nozzle 40a Tip 40b Body part 41 Operating unit 42 Suction circuit 43 Pump 44 Flow Sensor 45 Ultrasonic transducer with built-in flow channel 46 Analytical sensor part 47 Control Device 50 Suction nozzle housing 51 First valve 52 Second valve 53 Cleaning solution inlet 54 Wastewater outlet S Syringe

Claims

1. A vibrating body having a flat circular bottom surface and a reflecting surface located above the circular bottom surface and tapering upward; A circular plate-shaped piezoelectric element having a thickness-extension vibration mode, contacting the bottom surface of the vibrating body and having electrodes on both sides. Equipped with A processing flow path is provided at the center of the oscillator so as to pass through the oscillator in the vertical direction along a central axis line, An AC voltage of a predetermined frequency is applied to the piezoelectric element to excite ultrasonic waves, and the ultrasonic waves are reflected by the reflecting surface and directed toward the processing flow path.

1. A flow path built-in ultrasonic transducer.

2. The reflecting surface is a paraboloid of revolution.

2. The ultrasonic transducer according to claim 1 .

3. The paraboloid of revolution is formed so that the focal point of the ultrasonic waves reflected by it is the wall surface of the processing flow path.

3. The ultrasonic transducer according to claim 2.

4. The paraboloid of revolution is shaped such that the focal point of ultrasound reflected thereby is beyond the process flow path.

3. The ultrasonic transducer according to claim 2.

5. The paraboloid of revolution is shaped such that a focal point of ultrasonic waves reflected thereby is located within the process flow path.

3. The ultrasonic transducer according to claim 2.

6. The reflecting surface is a conical surface.

2. The ultrasonic transducer according to claim 1 .

7. The diameter of the vibrating body is 10 mm to 80 mm, and the height is 10 mm to 30 mm.

7. The ultrasonic transducer according to claim 1, wherein the ultrasonic transducer is a piezoelectric element.

8. The inner diameter of the piezoelectric element is 5 mm to 30 mm, and the thickness is 0.1 mm to 5 mm.

8. The ultrasonic transducer according to claim 7.

9. The vibrating body is made of an aluminum alloy, a titanium alloy, brass, or stainless steel.

9. The ultrasonic transducer according to claim 1, wherein the ultrasonic transducer is a piezoelectric element.

10. the vibrating body has an upper connector mounting hole and a lower connector mounting hole spaced apart from each other and facing each other along a central axis at its upper and lower central portions, and a through hole formed along the central axis between the upper connector mounting hole and the lower connector mounting hole, The through-hole functions as the processing flow path.

10. The ultrasonic transducer according to claim 1, wherein the ultrasonic transducer is a piezoelectric element.

11. The ultrasonic transducer further includes an upper connector and a lower connector that can be attached to the upper connector attachment hole and the lower connector attachment hole, each connector having a through hole along its central axis, When the upper connector and the lower connector are attached to the upper connector attachment hole and the lower connector attachment hole, the through hole of the connector and the through hole of the vibrator communicate with each other to form one flow path.

11. The ultrasonic transducer according to claim 10.

12. The upper connector and the lower connector each have a connection part at one end to which a tube or a pipe can be connected.

12. The ultrasonic transducer according to claim 11.

13. The vibrating body has an annular flange extending radially outwardly from its bottom.

13. The ultrasonic transducer according to claim 1, wherein the ultrasonic transducer is a piezoelectric element.

14. A vibrating body having a flat circular bottom surface and a reflecting surface located above the circular bottom surface and tapering upward; A circular plate-shaped piezoelectric element having a thickness-extension vibration mode, contacting the bottom surface of the vibrating body and having electrodes on both sides. Equipped with Two flow-path-embedded ultrasonic transducer pieces, each having a processing flow path that passes through the transducer in the vertical direction along the central axis at the center of the transducer, are stacked vertically so that the piezoelectric elements face each other and the processing flow paths are connected to each other; An AC voltage of a predetermined frequency is applied to each of the piezoelectric elements to excite ultrasonic waves, which are reflected by each reflecting surface and directed toward the processing flow path.

1. A flow path built-in ultrasonic transducer.

15. a syringe attachment section to which a syringe containing blood can be attached; a suction nozzle that enters the syringe attached to the syringe attachment portion and aspirates blood from the syringe; a suction pump connected to the suction nozzle; a sensor for analyzing components of the blood aspirated by the aspirating nozzle; a blood flow path that is connected from the suction nozzle to a waste liquid section via the sensor; A control device for controlling at least the operation of the suction pump; A blood gas analyzer comprising: The flow path-integrated ultrasonic transducer according to any one of claims 1 to 14 is provided so that the processing flow path is in communication with the blood flow path. A blood gas analyzer comprising:

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