JP4489461B2 - Ultrasonic probe and ultrasonic diagnostic apparatus - Google Patents

Description

  The present invention relates to an ultrasonic probe and an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic probe having a configuration in which a plurality of piezoelectric elements are arranged.

  An ultrasound diagnostic apparatus obtains in-vivo image information and the like by transmitting and receiving ultrasound to and from a living body using an ultrasound probe, and is used in various medical fields. The standard that the temperature of the contact surface with the living body must be maintained at 41 ° C. or lower is set for the ultrasonic probe used in the ultrasonic diagnostic apparatus. The surface temperature of an ultrasonic probe is generally proportional to the voltage applied to the probe. Therefore, in order to avoid an excessive temperature rise on the surface of the ultrasonic probe, the applied voltage is adjusted to be a specific value or less. However, when the applied voltage is reduced, the ultrasonic energy emitted from the probe is also reduced, so that the ultrasonic wave does not sufficiently reach the deep part in the living body, and the diagnostic ability of the deep part of the living body may be lowered.

Therefore, in order to keep the surface temperature of the ultrasonic probe within the standard without degrading the diagnostic ability of the deep part of the living body, it has been proposed to take measures against the ultrasonic probe (for example, Patent Document 1). ). FIG. 10 is a schematic diagram showing the configuration of a conventional ultrasonic probe in which such heat countermeasures are taken. The ultrasonic probe 1 includes a piezoelectric element 2 that transmits and receives ultrasonic waves, a ground electrode 3 provided on one surface of the piezoelectric element 2, and a signal electrode 4 provided on the other surface of the piezoelectric element 2. A signal electrical terminal 5 connected to the signal electrode 4, a ground electrode electrical terminal 6 connected to the ground electrode 3, and a back load material 7 provided on the back surface of the piezoelectric element 2. . The back load material 7 mechanically holds the piezoelectric element 2 and has a function of absorbing and dissipating heat of the piezoelectric element 2 in addition to a function of attenuating unnecessary ultrasonic signals. In such an ultrasonic probe, the heat generated from the piezoelectric element 2 and the heat generated by the multiple reflection of ultrasonic waves are absorbed by the back load material 7 and dissipated, so that the ultrasonic probe Suppresses excessive rise in surface temperature.
JP 2000-165959 A

  In such an ultrasonic probe, in order to further improve the diagnostic ability of the deep part of the living body while maintaining the surface temperature of the ultrasonic probe in an appropriate temperature range, further against heat generated from the piezoelectric element, etc. There is a need for improved heat dissipation.

  Therefore, an object of the present invention is to provide an ultrasonic probe with improved heat dissipation against heat generated from a piezoelectric element, and an ultrasonic diagnostic apparatus using the ultrasonic probe.

In order to achieve the above object, an ultrasonic probe according to the present invention performs ultrasonic transmission / reception with respect to a living body, converts the received wave into an electric signal, and transmits the electric signal to an ultrasonic diagnostic apparatus body. A piezoelectric element group in which a plurality of piezoelectric elements that transmit and receive ultrasonic waves are arranged with a gap therebetween, and a thermally conductive inter-piezoelectric element filling material that is filled in a gap between the piezoelectric elements; the have a piezoelectric element group thermal conductivity of the surrounding filler material disposed around the periphery filler, characterized in that it have a high hardness than the inter piezoelectric element filling material.

According to such a configuration, the heat generated from the piezoelectric elements can be absorbed by the inter-piezoelectric element filler filled between the piezoelectric elements and can be dissipated. As a result, the temperature rise of the contact surface of the ultrasonic probe with the living body can be suppressed. Further, since the mechanical strength of the element portion is improved by the presence of the filler between the piezoelectric elements, it is possible to suppress damage to the piezoelectric element due to external impact or the like.
Furthermore, since the heat generated from the piezoelectric elements can be absorbed by the filler between the piezoelectric elements and the surrounding filling portion, the temperature rise of the contact surface with the living body can be further suppressed.

  In the ultrasonic probe, it is preferable that the filler between the piezoelectric elements includes a polymer substance and an inorganic filler. In this case, it is preferable that the polymer substance includes at least one selected from the group consisting of epoxy resin, silicone rubber, and urethane rubber. The inorganic filler is preferably at least one selected from the group consisting of copper, silver, boron nitride, graphite, alumina, silica, aluminum nitride, silicon carbide and silicon nitride.

In this case, it is preferable that the surrounding filler includes a polymer substance and an inorganic filler. The polymer substance preferably includes at least one selected from the group consisting of epoxy resin, silicone rubber, and urethane rubber, and the inorganic filler includes copper, silver, boron nitride, graphite, alumina, silica, and aluminum nitride. , Preferably at least one selected from the group consisting of silicon carbide and silicon nitride .

  Moreover, it is preferable that the ultrasonic probe further includes a heat absorber that is thermally connected to the surrounding filler. This is because the temperature increase of the contact surface with the living body can be more reliably suppressed. In this case, the endothermic body preferably contains at least one of metal and carbon.

  In the ultrasonic probe, it is preferable that the piezoelectric elements are two-dimensionally arranged.

  An ultrasonic diagnostic apparatus of the present invention includes the ultrasonic probe of the present invention and an ultrasonic diagnostic apparatus main body electrically connected to the ultrasonic probe. According to such a configuration, since the probe in which the temperature rise of the contact surface with the living body is suppressed is used, the applied voltage of the ultrasonic probe is increased, and the energy of the transmitted ultrasonic wave is increased. can do. Therefore, it is possible to diagnose up to the deep part of the living body.

  According to the ultrasonic probe of the present invention, heat generated from the piezoelectric elements can be absorbed and radiated by the inter-piezoelectric element filler filled between the piezoelectric elements. As a result, the temperature rise of the contact surface of the ultrasonic probe with the living body can be suppressed. Further, since the mechanical strength of the element portion is improved by the presence of the filler between the piezoelectric elements, it is possible to suppress damage to the piezoelectric element due to external impact or the like.

  In addition, since the ultrasonic diagnostic apparatus using such an ultrasonic probe uses a probe in which the temperature rise of the contact surface with the living body is suppressed, the applied voltage of the ultrasonic probe is set. The energy of ultrasonic waves to be transmitted can be increased. Therefore, it is possible to diagnose up to the deep part of the living body.

  Hereinafter, an ultrasonic probe according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 9 is a schematic diagram showing an example of an ultrasonic diagnostic apparatus according to the present invention. This ultrasonic diagnostic apparatus drives an ultrasonic probe 1 that transmits / receives ultrasonic waves to / from a living body, and drives the ultrasonic probe 1 and receives a reception signal received by the ultrasonic probe 1. And an ultrasonic diagnostic apparatus main body 11 that displays a diagnostic image by performing signal processing. The ultrasonic probe 1 has a configuration as described below.

(First embodiment)
FIG. 1 is a perspective view showing an example of an ultrasonic probe according to the first embodiment of the present invention. The ultrasonic probe 1 includes a piezoelectric element group 2 that transmits / receives ultrasonic waves to / from a living body, and a back load material that mechanically holds the piezoelectric element group 2.

  The piezoelectric element group 2 includes a plurality of piezoelectric elements 2a arranged in a specific direction with a gap therebetween. The piezoelectric element 2a is made of, for example, a piezoelectric body such as piezoelectric ceramics, and includes electrodes (not shown) on the upper and lower surfaces thereof.

  The back surface load material 7 has a function of attenuating unnecessary ultrasonic signals, and the surface of the piezoelectric element 2a constituting the piezoelectric element group 2 opposite to the surface that transmits and receives ultrasonic waves (hereinafter referred to as “back surface”). "). The material constituting the back load material 7 is not particularly limited as long as it has ultrasonic attenuation characteristics, but preferably has thermal conductivity. Examples of such materials include main materials having ultrasonic attenuation characteristics such as nitrile rubber, butyl rubber and urethane rubber, metals such as copper and silver, inorganic oxides such as graphite, alumina and silica, and silicon carbide. Examples thereof include those filled with inorganic nitride inorganic fillers such as inorganic carbide, aluminum nitride, boron nitride and silicon nitride.

  Further, the ultrasonic probe 1 may include an acoustic matching layer, an acoustic lens, and the like on the ultrasonic transmission / reception surface of the piezoelectric element 2a in order to improve the ultrasonic transmission / reception efficiency.

  Further, in the ultrasonic probe 1, the inter-piezoelectric element filler 8 is filled in the gaps between the arranged piezoelectric elements 2 a. The inter-piezoelectric element filler 8 has a function of absorbing heat generated from the piezoelectric element 2a, and a material having thermal conductivity is used as the material thereof. The thermal conductivity of the inter-piezoelectric element filler 8 is not particularly limited, but the thermal conductivity of a polymer material such as a general epoxy resin or silicone rubber as a filler is about 0.3 W / mK, More than that, it is preferably 0.5 to 20 W / mK, and more preferably 2 to 20 W / mK. The inter-piezoelectric filler 8 is preferably made of a material that is small in deformation (expansion and contraction) due to temperature changes.

  As a material of such an inter-piezoelectric element filler 8, for example, a material obtained by dispersing an inorganic filler having a higher thermal conductivity than that of the main material in a polymer material as the main material can be used.

  For example, a resin such as an epoxy resin, a rubber such as a silicone rubber, a urethane rubber, or the like can be used as the polymer material as the main material. Examples of the inorganic filler include metals such as copper and silver, inorganic oxides such as graphite, alumina and silica, inorganic carbides such as silicon carbide, and inorganic nitrides such as aluminum nitride, boron nitride and silicon nitride. It is done.

  Further, the blending ratio of these components is preferably adjusted so as to obtain the thermal conductivity as described above. Such a compounding ratio is set according to the kind of the inorganic filler to be used and the like, but it is preferable to add the inorganic filler to the polymer substance in a weight ratio of 50% to 90%.

  The inter-piezoelectric element filling material 8 only needs to be filled in the gaps between the piezoelectric elements 2a. However, as shown in FIG. . According to such a configuration, the volume of the inter-piezoelectric element filler 8 is increased, and the contact area between the inter-piezoelectric element filler 8 and the back surface load material 7 is increased. For this reason, the heat capacity of the inter-piezoelectric filler 8 is increased, and the heat absorption is improved. In addition, the heat absorbed by the inter-piezoelectric filler 8 is easily transferred to the back surface load material 7. This is because the effect of reducing the temperature of the contact surface of the acoustic probe 1 with the living body is further enhanced.

  When an acoustic matching layer, an acoustic lens, or the like is disposed on the transmission / reception surface of the piezoelectric element 2a, it is preferable to dispose the inter-piezoelectric filler 8 so as to be in thermal contact with these members. This is because heat generated by the ultrasonic attenuation characteristics of the acoustic matching layer and the acoustic lens can also be absorbed by the inter-piezoelectric filler 8. As such a configuration, for example, a configuration in which the gap between the acoustic matching layers provided corresponding to each piezoelectric element 2a is filled with the inter-piezoelectric element filler 8 can be cited.

  Next, an example of a method for manufacturing the ultrasonic probe will be described.

  First, the back load material 7 is prepared, and a piezoelectric body is disposed thereon. Then, the piezoelectric element group 2 is formed by dividing the piezoelectric body into individual piezoelectric elements 2a by a dividing unit such as a dicing apparatus. At this time, a metal film such as gold or nickel is formed in advance on the upper and lower surfaces of the piezoelectric body by, for example, plating or sputtering, and divided into piezoelectric films 2a each having electrodes on the upper and lower surfaces. Can be formed.

  Thereafter, the filler formed in the grooves (that is, the gap between the piezoelectric elements) formed at the time of division is filled with the filler precursor.

  The filler precursor is adjusted by kneading a main material precursor capable of forming a polymer compound as a main material as described above by curing and an inorganic filler. In the case of forming an inter-piezoelectric element filler mainly composed of an epoxy resin, as a main material precursor, for example, a prepolymer such as a bisphenol A type epoxy resin or a bisphenol F type epoxy resin, a curing agent and an effect promotion as appropriate. A composition containing an additive such as an agent can be used. Moreover, the filler precursor may contain additives such as a coupling agent, a dispersing agent, a colorant, and a release agent as necessary. In addition, the filler precursor may contain a solvent that can be volatilized in a subsequent step in order to obtain a viscosity suitable for filling between the piezoelectric elements 2a.

  As a filling method of the filler precursor, for example, an appropriate amount of filler precursor is supplied onto the piezoelectric element group 2, and then the excess filler precursor is removed by a squeegee and the gap between the piezoelectric elements 2a is filled. A method of filling the material precursor can be employed. In addition, it is preferable to perform filling under reduced pressure, or to perform heat treatment under reduced pressure after filling so that the entire gap between the piezoelectric elements 2a can be filled reliably.

  Subsequently, the inter-piezoelectric element filler precursor is cured to form the inter-piezoelectric element filler 8. Furthermore, the ultrasonic probe 1 is manufactured by providing an acoustic matching layer, an acoustic lens, and the like on the surface opposite to the back load material 7 side of the piezoelectric element 2a as necessary.

  Next, the operation of the ultrasonic probe will be described. First, the ultrasonic probe 1 is brought into contact with the living body surface to be inspected. Then, an electrical signal (transmission signal) is transmitted from the ultrasonic diagnostic apparatus main body to the ultrasonic probe, and a voltage is applied between the electrodes of the piezoelectric element 2, whereby the electrical signal is converted into an ultrasonic signal in the piezoelectric element 2 a. And is transmitted to the living body. The ultrasonic signal transmitted to the living body is reflected by a test object (for example, an organ, a blood vessel, etc.) in the living body. This reflected wave is received by the piezoelectric element 2a, converted into an electrical signal (received signal), and transmitted to the ultrasonic diagnostic apparatus body. The received signal is subjected to signal processing in the ultrasonic diagnostic apparatus body, and a diagnostic image is constructed. By performing this operation while scanning the ultrasonic wave with the piezoelectric element, two-dimensional information of the test object can be obtained.

  According to the ultrasonic probe according to the present embodiment, the heat generated by the mechanical loss (elastic loss) and the electrical loss (dielectric loss) of the piezoelectric element 2a is caused by the inter-piezoelectric element filler 8 having high thermal conductivity. The heat is absorbed from the side surface of each piezoelectric element 2a. Then, this heat is radiated from the end face of the inter-piezoelectric filler 8 or is transferred from the inter-piezoelectric filler 8 to the back load material 7. As a result, the temperature rise of the contact surface of the ultrasonic probe with the living body, that is, the transmission / reception surface of the piezoelectric element 2a can be reduced.

(Second Embodiment)
FIG. 2 is a perspective view showing an example of an ultrasonic probe according to the second embodiment of the present invention. In this figure, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The ultrasonic probe according to this embodiment includes a piezoelectric element group 2 in which a plurality of piezoelectric elements are arranged, and a back load member 7 that mechanically holds the piezoelectric element group 2. A thermally conductive inter-piezoelectric filler 8 is disposed in the gap between the piezoelectric elements 2a.

  Further, a surrounding filling portion 9 is provided around the piezoelectric element group 2 so as to surround it. The surrounding filling portion 9 has a function of absorbing heat generated from the piezoelectric elements 2a, similarly to the filling material 8 between the piezoelectric elements, and a material having thermal conductivity is used as the material. The thermal conductivity of the surrounding filling portion 9 is not particularly limited, but the thermal conductivity of a polymer material such as a general epoxy resin or silicone rubber as a filler is about 0.3 W / mK, and more For example, it is 0.5 to 20 W / mK, and more preferably 2 to 20 W / mK. In addition, as a material of such a surrounding filling part 9, the material similar to what was illustrated as a material which comprises the filler 8 between piezoelectric elements in 1st Embodiment can be used, for example.

  Note that the ultrasound probe according to the present embodiment has the same configuration as that of the first embodiment except that a surrounding filling portion 9 is provided around the piezoelectric element group 2.

  The ultrasonic probe can be manufactured as follows, for example. First, a piezoelectric body is arranged on the back load material 7, and the piezoelectric body is divided into individual piezoelectric elements 2. This step can be performed in the same manner as in the first embodiment. Thereafter, a wall having a height equal to the thickness of the piezoelectric element group 2 is temporarily provided with an appropriate gap between the piezoelectric element group 2 and surrounding the piezoelectric element group 2. In this state, the filler precursor is filled between the groove formed during the division (the gap between the piezoelectric elements 2a) and the piezoelectric element group 2 and the temporary wall by the same operation as in the first embodiment. , Cure this. Thereby, the filling material 8 between piezoelectric elements and the surrounding filling part 9 can be formed in the state integrated with each other with the same material. Thereafter, the hypothetical wall is removed, and an acoustic matching layer, an acoustic lens, and the like are provided as necessary, whereby the ultrasonic probe is manufactured.

  Note that the operation of the ultrasound probe according to the present embodiment is the same as the operation of the first embodiment, and a description thereof will be omitted.

  According to the ultrasonic probe according to the present embodiment, the heat generated by the mechanical loss (elastic loss) and the electrical loss (dielectric loss) of the piezoelectric element 2a is caused by the inter-piezoelectric element filler 8 having high thermal conductivity. The heat is absorbed from all four side surfaces of each piezoelectric element 2. This heat is transmitted from the end face of the inter-piezoelectric filler 8 to the peripheral filling portion 9 and is radiated from the end face of the peripheral filling portion 9. Alternatively, heat is transferred from the inter-piezoelectric filler 8 and the surrounding filler 9 to the back load member 7. As a result, the temperature rise of the contact surface of the ultrasonic probe with the living body, that is, the transmission / reception surface of the piezoelectric element 2 can be reduced.

  In particular, since the end face of the peripheral filling portion 9 has a larger area than the end face of the inter-piezoelectric element filler 8 in the first embodiment, the heat dissipation effect is further enhanced. Furthermore, since the area where the surrounding filling part 9 and the back surface load material 7 contact is also added, the heat transfer effect to the back surface load material 7 is also enhanced. Further, since the amount of the whole filling material including the inter-piezoelectric filling material 8 and the surrounding filling portion 9 is large, the heat capacity increases. By these effects, the temperature rise of the biological contact surface of the ultrasonic probe can be further reduced.

  In the above description, the form in which the surrounding filling portion 9 surrounds the entire periphery of the piezoelectric element group 2 is exemplified, but the present invention is not limited to such a form. Even when the surrounding filling portion 9 is provided only in a part of the periphery of the piezoelectric element group 2, the above-described effect can be achieved.

  In the above description, the case where the inter-piezoelectric element filling material 8 and the surrounding filling portion 9 are all made of the same material has been exemplified, but the present invention is not limited to this. The surrounding filler 9 may be made of a material different from the inter-piezoelectric filler 8 as long as the filler has a thermal conductivity as described above.

  In this case, it is preferable that the surrounding filling portion 9 is made of a material having higher hardness than the inter-piezoelectric element filling material 8. This is because the mechanical strength of the probe can be further improved. As such a form, for example, a form in which the peripheral filling portion 9 is made of a material mainly made of epoxy resin and a filler between piezoelectric elements is made of a material mainly made of silicone rubber can be cited.

  As a manufacturing method in this case, the following method can be employed. After the piezoelectric element group 2 is formed, a wall is temporarily installed so as not to leave a gap between the piezoelectric element group 2 and surrounding the piezoelectric element group 2. Thereafter, only the gap between the piezoelectric elements 2a is filled with, for example, a filler precursor for forming silicone rubber, and cured to form the inter-piezoelectric filler 8. Then, after removing the temporary wall, a gap is formed between the piezoelectric element group 2 so as to surround the periphery of the piezoelectric element group 2, and the wall is temporarily installed, and then, for example, an epoxy resin is formed. The filler precursor is filled and cured to form the peripheral filling portion 9. And after removing the temporary wall, the said ultrasonic probe is produced by providing an acoustic matching layer, an acoustic lens, etc. suitably.

(Third embodiment)
FIG. 3 is a perspective view showing an example of an ultrasonic probe according to the third embodiment of the present invention. In this figure, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The ultrasonic probe according to this embodiment includes a piezoelectric element group 2 in which a plurality of piezoelectric elements 2 a are arranged, and a back load material 7 that mechanically holds the piezoelectric element group 2. A thermally conductive inter-piezoelectric filler 8 is disposed in the gap between the piezoelectric elements 2.

  Further, a heat absorber 10 is disposed so as to be in thermal contact with the inter-piezoelectric filler 8. For example, as shown in the figure, the heat absorber 10 can be disposed on the side surface of the back load material 7 in a state of being in contact with the end face of the inter-piezoelectric element filler 8. The heat absorbing body 10 is for further absorbing the heat absorbed by the inter-piezoelectric element filler 8, and a material having high thermal conductivity is used as the material. Examples of such a material include metals such as copper, silver, and aluminum, or graphite. Further, the shape of the heat absorber 10 is not particularly limited, but it is preferable that the volume and the surface area are large from the viewpoint of making the heat capacity and heat dissipation as high as possible. Examples of the shape of the endothermic body 10 include a sheet shape and a plate shape as illustrated.

  Further, the heat absorber 10 may be provided so as to be in thermal contact with only one end face side of the inter-piezoelectric filler 8, but is preferably provided so as to be in thermal contact with both end faces. In this case, it is possible to expect a heat countermeasure effect that is approximately twice that of the case where only one end face side of the inter-element filler 8 is provided.

  Note that the ultrasonic probe according to the present embodiment has the same configuration as that of the first embodiment except that the heat absorber is provided.

  The ultrasonic probe can be manufactured as follows, for example. First, the ultrasonic probe according to the first embodiment is manufactured by the method as described above. Thereafter, the heat absorbing body 10 is disposed on the side surface of the back load material 7 in a state where it is in contact with the end surface of the inter-piezoelectric filler 8. At this time, it is preferable to reduce the thermal resistance between the heat absorber 10 and the inter-piezoelectric element filler 8 by interposing an adhesive having high thermal conductivity such as a heat radiating silicone adhesive. .

  Note that the operation of the ultrasound probe according to the present embodiment is the same as the operation of the first embodiment, and a description thereof will be omitted.

  According to the ultrasonic probe of the present embodiment, the heat generated by the mechanical loss (elastic loss) and the electrical loss (dielectric loss) of the piezoelectric element 2a is caused by the inter-piezoelectric element filler 8 having a high thermal conductivity. Heat is absorbed from the side surface of each piezoelectric element 2a. This heat propagates from the end face of the inter-piezoelectric filler 8 to the heat absorber 10 and is absorbed by the heat absorber 10 or radiated from the heat absorber 10. As a result, the temperature rise of the contact surface of the ultrasonic probe with the living body, that is, the transmission / reception surface of the piezoelectric element 2a can be reduced.

  In the above description, the case where the heat absorber 10 is provided in contact with the inter-piezoelectric element filler 8 is illustrated, but the present invention is not limited to this. For example, in the configuration in which the surrounding filler 9 is arranged around the piezoelectric element group 2 as in the ultrasonic probe according to the second embodiment, the heat absorber 10 is brought into contact with the surrounding filler 9. It may be provided. According to such a form, the heat absorbed by the inter-piezoelectric filler 8 propagates from the end surface of the peripheral filling portion 9 to the heat absorbing body 10 via the peripheral filling portion 9 and is absorbed by the heat absorbing body 10. Or is dissipated from the endothermic body 10.

  FIG. 4 is a perspective view showing an example of such an ultrasonic probe. In such a configuration, the heat absorber 10 can be disposed on the side surface of the back load member 7 in a state of being in contact with the end surface of the surrounding filling portion 9 as shown in the figure, for example. At this time, it is preferable to reduce the thermal resistance between the heat absorbing body 10 and the surrounding filling portion 9 by interposing an adhesive having a high thermal conductivity such as a heat radiating silicone adhesive.

  Further, the heat absorber 10 may be provided so as to be in contact with at least one side surface of the peripheral filling portion 9, but as shown in the figure, the heat absorber 10 is provided on the two end surfaces of the peripheral filling portion 9 and further on all four side surfaces. It is preferable to provide it.

  Moreover, in the ultrasonic probe 1 shown in FIG. 4, although the case where the surrounding filling part 9 was given to the perimeter of the piezoelectric element group 2 arranged in multiple numbers is illustrated, the surrounding filling part 9 is a surrounding. It may be provided only in a part, and in that case, the heat absorber 10 may be provided in accordance with the location where the surrounding filling portion 9 is provided.

(Fourth embodiment)
FIG. 5 is a perspective view showing an example of an ultrasonic probe according to the fourth embodiment of the present invention. In this figure, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The ultrasonic probe according to this embodiment includes a piezoelectric element group 2 in which a plurality of piezoelectric elements 2 a are arranged, and a back load material 7 that mechanically holds the piezoelectric element group 2. A thermally conductive inter-piezoelectric filler 8 is disposed in the gap between the piezoelectric elements 2a.

  In the present embodiment, the piezoelectric element group 2 includes a plurality of piezoelectric elements 2a arranged in two specific directions with a gap therebetween. That is, the piezoelectric element group 2 has a configuration in which a plurality of piezoelectric elements 2a are two-dimensionally arranged.

  In addition, in this figure, although the form where the shape of each piezoelectric element 2a is a quadrangular prism is illustrated, it is not limited to this, It can also be set as other shapes, such as a cylinder. Moreover, in this figure, although the form in which the piezoelectric elements 2a are arranged in two directions orthogonal to each other is illustrated, the present invention is not limited to this, and any two-dimensional arrangement form can be used. Such an array form may be used.

  Note that the ultrasonic probe according to the present embodiment has the same configuration as that of the first embodiment except that the piezoelectric element group 2 arranged two-dimensionally as described above is used.

  The ultrasonic probe can be manufactured as follows, for example. A piezoelectric body is arranged on the back load material 7, and this is cut into a lattice shape by a dividing means such as a dicing device, for example, and a piezoelectric element group 2 is formed in which the piezoelectric elements 2a are two-dimensionally arranged. To do. At this time, in the same manner as in the first embodiment, a metal film is formed in advance on the upper and lower surfaces of the piezoelectric body, and by dividing it, the piezoelectric elements 2a each having electrodes on the upper and lower surfaces are formed. Can do.

  Thereafter, a filler precursor is filled into grooves formed at the time of division (that is, a gap between the piezoelectric elements 2 a), and this is cured to form the inter-piezoelectric filler 8. And the said ultrasonic probe is produced by providing an acoustic matching layer, an acoustic lens, etc. as needed. Note that these steps can be performed in the same manner as in the first embodiment.

  Note that the operation of the ultrasound probe according to the present embodiment is substantially the same as the operation of the first embodiment. In the present embodiment, by using a piezoelectric element group in which a plurality of piezoelectric elements are arranged two-dimensionally, three-dimensional information of a test object can be constructed in real time.

  According to the ultrasonic probe according to the present embodiment, as in the first embodiment, the heat generated from the piezoelectric elements 2a is transferred to the side surfaces of the piezoelectric elements 2 by the inter-piezoelectric element filler 8 having high thermal conductivity. The heat is absorbed from. Then, this heat is radiated from the end face of the inter-piezoelectric filler 8 or is transferred from the inter-piezoelectric filler 8 to the back load material 7. As a result, the temperature rise of the contact surface of the ultrasonic probe with the living body, that is, the transmission / reception surface of the piezoelectric element 2a can be reduced.

  In particular, in the present embodiment, since the piezoelectric elements 2a are two-dimensionally arranged, the volume ratio of the inter-piezoelectric filler 8 to the piezoelectric elements 2a is large, and at least the piezoelectric element group 2 is piezoelectric except for the outer peripheral portion. Heat is transmitted from the entire side surface of the element 2a to the filler 8 between piezoelectric elements. Therefore, the endothermic effect by the inter-piezoelectric element filler 8 is further increased as compared with the case where the piezoelectric elements 2a are arranged in one dimension, and the effect of lowering the surface temperature is high.

  In the present embodiment, it is also possible to adopt a configuration in which the surrounding filler 9 is arranged around the piezoelectric element group 2 as in the ultrasonic probe according to the second embodiment. FIG. 6 is a perspective view showing an example of such an ultrasonic probe. The ultrasonic probe having such a configuration can have the same configuration as that of the second embodiment except that the piezoelectric element group 2 in which the piezoelectric elements 2a are two-dimensionally arranged is used.

  In the present embodiment, as in the ultrasonic probe according to the third embodiment, the heat absorber 10 is further arranged so as to be in contact with the inter-piezoelectric filler 8 or the surrounding filler 9. It is also possible. 7 and 8 are perspective views showing an example of such an ultrasonic probe. The ultrasonic probe having such a configuration can have the same configuration as that of the third embodiment except that the piezoelectric element group 2 in which the piezoelectric elements 2a are two-dimensionally arranged in two is used.

  As described above, the ultrasonic probe according to the present invention reduces the temperature rise of the contact surface of the ultrasonic probe with the living body by absorbing the heat generated from the piezoelectric element by the filler between the piezoelectric elements. This makes it possible to perform ultrasound diagnosis with higher safety. Therefore, it is useful as a probe constituting an ultrasonic diagnostic apparatus utilized in various medical fields.

It is a perspective view which shows an example of the ultrasonic probe which concerns on the 1st Embodiment of this invention. It is a perspective view which shows an example of the ultrasonic probe which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows an example of the ultrasonic probe which concerns on the 3rd Embodiment of this invention. It is a perspective view which shows another example of the ultrasonic probe which concerns on the 3rd Embodiment of this invention. It is a perspective view which shows an example of the ultrasonic probe which concerns on the 4th Embodiment of this invention. It is a perspective view which shows another example of the ultrasonic probe which concerns on the 4th Embodiment of this invention. It is a perspective view which shows another example of the ultrasonic probe which concerns on the 4th Embodiment of this invention. It is a perspective view which shows another example of the ultrasonic probe which concerns on the 4th Embodiment of this invention. 1 is a schematic diagram illustrating an example of an ultrasonic diagnostic apparatus according to the present invention. It is sectional drawing which shows the conventional ultrasonic probe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 2 Piezoelectric element group 2a Piezoelectric element 3 Ground electrode 4 Signal electrode 5 Signal electrical terminal 6 Ground electrode electrical terminal 7 Back load material 8 Filler between piezoelectric elements 9 Surrounding filling part 10 Heat absorber 11 Super Ultrasonic diagnostic equipment

Claims (13)

An ultrasound probe that transmits and receives ultrasound to and from a living body, converts the received wave into an electrical signal, and transmits the electrical signal to the ultrasound diagnostic apparatus body,
A piezoelectric element group in which a plurality of piezoelectric elements that transmit and receive ultrasonic waves are arranged with a gap therebetween,
A thermally conductive filler between piezoelectric elements filled in a gap between the piezoelectric elements ; and
Possess a peripheral filler disposed thermal conductivity around the piezoelectric element group,
It said ambient filler, ultrasonic probe, characterized in that have a hardness greater than the inter piezoelectric element filling material.   The ultrasonic probe according to claim 1, wherein the inter-piezoelectric filler includes a polymer substance and an inorganic filler.   The ultrasonic probe according to claim 2, wherein the polymer substance includes at least one selected from the group consisting of epoxy resin, silicone rubber, and urethane rubber.   The ultrasonic probe according to claim 2, wherein the inorganic filler is at least one selected from the group consisting of copper, silver, boron nitride, graphite, alumina, silica, aluminum nitride, silicon carbide, and silicon nitride.   Furthermore, the ultrasonic probe in any one of Claims 1-4 containing the thermal absorption body thermally connected with the said filler between piezoelectric elements.   The ultrasonic probe according to claim 5, wherein the heat absorber includes at least one of metal and carbon. It said peripheral filler ultrasonic probe according to claim 1 further comprising a polymer material and an inorganic filler. The ultrasonic probe according to claim 7 , wherein the polymer substance includes at least one selected from the group consisting of epoxy resin, silicone rubber, and urethane rubber. The ultrasonic probe according to claim 7 , wherein the inorganic filler is at least one selected from the group consisting of copper, silver, boron nitride, graphite, alumina, silica, aluminum nitride, silicon carbide, and silicon nitride. Further, the ultrasonic probe according to any one of claims 1 to 9 including the surrounding filler and thermally connected heat absorbers. The ultrasonic probe according to claim 10 , wherein the heat absorber includes at least one of metal and carbon. An ultrasonic probe according to any one of claims 1 to 11, wherein the piezoelectric element is two-dimensionally arranged An ultrasonic diagnostic apparatus comprising: the ultrasonic probe according to any one of claims 1 to 12 ; and an ultrasonic diagnostic apparatus main body electrically connected to the ultrasonic probe.

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