JP2006204622A - Ultrasonic probe and ultrasonic image device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic probe provided with high operatability, thermolysis property, quality and dependability. <P>SOLUTION: The probe is equipped with a case 10 to be gripped by an operator, a transducer 20 which is stored in the case and transmits and receives an ultrasonic wave from the end part of the case to a subject, a cable 50 which is connected to the proximal end part of the case and transmits and receives electric signals to the transducer, and a waterproof mold material 40 to fill the gap between the case and the proximal end part of the transducer. A hollow metal material 41 is mixed in the mold material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ultrasonic probe and an ultrasonic imaging apparatus that scan an inside of a subject with an ultrasonic wave to form an image of the internal state of the subject, and particularly, the case of the ultrasonic probe is filled. The present invention relates to a mold material for waterproofing.

  2. Description of the Related Art There is known an ultrasonic diagnostic apparatus that scans an inside of a subject with ultrasonic waves and images an internal state of the subject based on a reception signal generated from a reflected wave from the inside of the subject. This ultrasonic diagnostic device transmits ultrasonic waves from the ultrasonic probe into the subject, and receives the reflected waves generated by the mismatch of acoustic impedance inside the subject with the ultrasonic probe to generate a received signal. To do.

  When ultrasonic waves are transmitted and received from the ultrasonic probe, electrical energy and mechanical energy are exchanged in the piezoelectric vibrator. At this time, heat is generated from the piezoelectric vibrator, and the reliability is lowered due to the thermal deterioration of the material, or the quality is lowered due to the characteristic variation of the material.

  Further, the ultrasonic probe has a heat generation regulation [IEC 60601-2-37 (2001)], and if the output power is suppressed so as not to exceed the heat generation regulation, the original diagnostic ability may not be exhibited. .

  Therefore, in order to prevent deterioration of the reliability and quality of the ultrasonic probe and to make the ultrasonic probe exhibit its original diagnostic ability, the heat generated by the piezoelectric vibrator is detected by the ultrasonic probe. It is necessary to efficiently dissipate heat from the contact.

  By the way, in the ultrasonic probe, there is a technique of filling the internal space of the ultrasonic probe with a molding material in order to protect the internal structure from impact and water leakage. As the mold material, a low-density epoxy resin, foamed polyurethane, or the like is used so as not to impair the operability of the ultrasonic probe.

  However, low density materials such as epoxy resin and polyurethane foam generally have low thermal conductivity, and heat generated by the piezoelectric vibrator cannot be efficiently radiated from the backing material to the cable.

Therefore, in recent years, an ultrasonic probe in which a heat transfer wire is disposed between a back material and a cable has been proposed as a technique for efficiently radiating heat generated by a piezoelectric vibrator (see, for example, Patent Document 1). .
JP-A-5-244690

  However, the technique proposed in Patent Document 1 requires the arrangement of a heat transfer wire in the ultrasonic probe, and there are problems that the structure is complicated and that the operability is reduced due to an increase in weight. is there.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an ultrasonic probe and an ultrasonic imaging apparatus having high operability, heat dissipation, quality, and reliability. There is to do.

  In order to solve the problems and achieve the object, the ultrasonic probe and the ultrasonic imaging apparatus of the present invention are configured as follows.

(1) A case gripped by an operator, a transducer housed in the case and transmitting / receiving ultrasonic waves to / from a subject from a distal end portion of the case, connected to a proximal end portion of the case, and the transducer A cable for transmitting and receiving electrical signals, and a waterproof mold material filled between the case and the base end of the transducer, and a hollow metal material is mixed in the mold material Yes.

(2) In the ultrasonic probe described in (1), the hollow metal material is a carbon filler or a gold filler.

(3) In the ultrasonic probe described in (1), the hollow metal material is carbon fiber or gold fiber.

(4) In the ultrasonic probe described in (1), the molding material is in contact with the shield wire of the cable.

(5) In an ultrasonic imaging apparatus having an ultrasonic probe, the ultrasonic probe is accommodated in a case gripped by an operator, the case, and the subject from the tip of the case to the subject. A transducer for transmitting and receiving ultrasonic waves, a cable connected to the base end of the case and transmitting and receiving electrical signals to and from the transducer, and a waterproofing filling between the case and the base end of the transducer The mold material is mixed with a hollow metal material.

  According to the present invention, the operability, heat dissipation, quality, and reliability of the ultrasound probe and the ultrasound imaging apparatus are improved.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Configuration of ultrasonic diagnostic equipment)
FIG. 1 is a schematic view of an ultrasonic diagnostic apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the ultrasonic diagnostic apparatus (ultrasonic image apparatus) according to the present embodiment images an internal state of a subject using ultrasonic waves. The ultrasonic diagnostic apparatus main body 2 is comprised.

  FIG. 2 is a configuration diagram of the ultrasound probe 1 according to the embodiment.

  As shown in FIG. 2, the ultrasonic probe 1 includes a case 10 held by an operator, and a transducer 20 that is disposed in the case 10 and transmits / receives ultrasonic waves to / from a subject from the distal end portion of the case 10. And a flexible printed circuit (hereinafter referred to as “FPC”) 30 that is disposed in the case 10 and transmits and receives electrical signals to and from the transducer 20, and is filled between the transducer 20 and the base end of the case 10. Embedded in the molding material 40, which is connected to the base material of the case 10 and prevents the infiltration of moisture into the case 10, and is connected to the FPC 30 and the ultrasonic diagnostic apparatus main body 2. A shield plate 60 is provided to protect the FPC 30 from noise.

  Next, each component will be described in detail. In the following description, the distal end side of the case 10 is the upper side, and the proximal end side of the case 10 is the lower side.

[Case 10]
As shown in FIG. 2, the case 10 includes an opening 11 at the upper end and an insertion hole 12 at the lower end. The transducer 20 (actually the acoustic lens 26) is exposed from the opening 11, and the cable 50 is inserted into the insertion hole 12.

[Transducer 20]
FIG. 3 is a perspective view of the transducer 20 according to the embodiment.

  As shown in FIG. 3, the transducer 20 includes a piezoelectric vibrator 21, an acoustic matching layer 22, a back material 23, and an acoustic lens 24.

  The piezoelectric vibrator 21 substantially transmits and receives ultrasonic waves. The piezoelectric vibrator 21 includes a large number of piezoelectric elements 211. These piezoelectric elements 211 have a strip shape and are arranged at predetermined intervals in a direction substantially perpendicular to the axial center line of the case 10.

  As a material of the piezoelectric element 211, a two-component or three-component piezoelectric ceramic or the like is used. Hereinafter, the arrangement direction of the piezoelectric elements 211 is defined as an array direction, and a direction substantially perpendicular to the array direction and the vertical direction is defined as a lens direction.

  A groove portion of the piezoelectric vibrator 21, that is, a gap between the piezoelectric elements 211 and 211, is filled with a resin material (not shown) for ensuring the mechanical strength of the piezoelectric vibrator 21. An epoxy resin or the like is used as the material for the resin material.

  Each piezoelectric element 211 includes a GND electrode 211a on the upper end surface and a signal electrode 211b on the lower end surface. By applying an electric signal between these electrodes 211a and 211b, the piezoelectric element 211 has an axial direction, that is, an upper and lower direction. An ultrasonic wave can be generated in the direction.

  A common electrode 212 for electrically sharing the GND electrode 211a of each piezoelectric element 211 is joined to one side surface of the piezoelectric vibrator 21 in the lens direction over the entire region in the array direction. The GND wiring 31 of the FPC 30 described above is connected to each GND electrode 211a via the common electrode 212, and the signal wiring 32 of the FPC 30 is connected to each signal electrode 211b.

  The acoustic matching layer 22 matches the acoustic impedance between the piezoelectric vibrator 21 and the subject. The acoustic matching layer 22 is disposed on the upper side of the piezoelectric vibrator 21 and includes a large number of acoustic matching elements 221.

  These acoustic matching elements 221 have a strip shape and are arranged at equal pitch intervals as the piezoelectric elements 211 in the array direction and the lens direction.

  A groove portion of the acoustic matching layer 22, that is, a gap between the acoustic matching element 221 and the acoustic matching element 221 is filled with a resin material (not shown) for ensuring the mechanical strength of the acoustic matching layer 22. An epoxy resin or the like is used as the material for the resin material.

  The backing material 23 attenuates ultrasonic waves propagating to the lower side of the ultrasonic waves generated by the piezoelectric vibrator 21, that is, the operator's hand side. The back material 23 is disposed below the piezoelectric vibrator 21. As the material for the back member 23, rubber having a high damping action is used.

  The acoustic lens 24 converges the ultrasonic beam by utilizing acoustic refraction, and improves the ultrasonic resolution. The acoustic lens 24 is arranged on the upper side of the acoustic matching layer 22 so as to cover all the acoustic matching elements 221.

  Silicone rubber or the like is used as a material for the acoustic lens 24. Further, the acoustic impedance of the acoustic lens 24 is set to a value close to the acoustic impedance of the subject in order to prevent reflection of ultrasonic waves at the contact surface between the subject and the acoustic lens 24.

[FPC30]
As shown in FIG. 2, the FPC 30 is disposed on one side of the transducer 20 in the lens direction, and mainly has a planar two-layer structure including a GND wiring 31 and a signal wiring 32. The GND wiring 31 and the signal wiring 32 are separated in the middle of the FPC 30, and are connected to the common electrode 212 and the signal electrode 211b at the respective leading ends.

[Mold material 40]
As shown in FIG. 2, the molding material 40 transfers the heat of the transducer 20, which is an important point of the present invention, from the back material 23 to the cable 50 side in addition to preventing moisture from entering the case 10. Have a role.

  FIG. 4 is an enlarged view of the molding material 40 according to the embodiment.

  As shown in FIG. 4, a spherical metal shell 41 having a high thermal conductivity is mixed in the molding material 40 for the purpose of increasing the thermal conductivity and decreasing the density. As the material of the mold material 40, in consideration of the operability of the ultrasonic probe 1, a low density epoxy resin, polyurethane foam, or the like is used. Moreover, as the hollow metal material 41, a carbon filler, a gold filler, or the like is used.

  The inventor experimented how the characteristics of the mold material 40 changed due to the mixing of the hollow metal material 41. In this experiment, an epoxy resin is used as the mold material 40, and a carbon filler having a diameter of 40 [nm] and a porosity of 60 [%] is used as the hollow metal material 41.

  The experimental results are shown below.

  FIG. 5 is a graph showing the relationship between the mixing ratio of the hollow metal material 41 and the thermal conductivity of the molding material 40 according to the embodiment.

  5 that the thermal conductivity of the molding material 40 increases as the mixing ratio of the carbon filler increases. Incidentally, the thermal conductivity of a general epoxy resin is about 0.2 [W / mK], but when the mixing ratio of the carbon filler is increased to about 50 [wt%], the thermal conductivity of the molding material 40 is about It has risen to 1.8 times.

  FIG. 6 is a graph showing the relationship between the mixing ratio of the hollow metal material 41 and the density of the molding material 40 according to the embodiment.

  It can be seen from FIG. 6 that the density of the molding material 40 decreases as the mixing ratio of the carbon filler increases.

  From this experiment, it was confirmed that the heat of the transducer 20 can be efficiently transferred from the backing material 23 to the cable 50 side and the weight of the ultrasonic probe 1 can be reduced by mixing the hollow metal material 41 into the mold material 40. It was done.

[Cable 50]
FIG. 7 is a cross-sectional view of the cable 50 according to the embodiment.

  As shown in FIG. 7, the cable 50 includes a plurality of signal lines 51, a resin material 52 that covers the periphery of the signal lines 51, a large number of shield wires 53 that are knitted annularly around the outer periphery of the resin material 52, and a shield The outer skin 54 covers the outside of the wire 53, and one end of the wire 53 enters the case 10 through the insertion hole 12 and enters the molding material 40.

  FIG. 8 is an enlarged view of a connection portion between the case 10 and the cable 50 according to the embodiment.

  As shown in FIG. 8, the shield wire 53 is exposed from the cable 50 and connected to a shield plate 60 embedded in the molding material 40. As a material for the shield wire 53, copper, aluminum, or the like having high conductivity is used.

[Shield plate 60]
As shown in FIG. 8, the shield plate 60 has a role of releasing the heat of the molding material 40 to the shield wire 53 of the cable 50 in addition to protecting the FPC 30 from noise. A plurality of holes 61 are formed in the shield plate 60 in order to increase the contact area with the molding material 40. As a material for the shield plate 60, copper, aluminum, or the like having high conductivity is used.

(Manufacturing process of ultrasonic probe)
Next, a manufacturing process of the ultrasonic probe 1 having the above configuration will be briefly described.

  First, the transducer 20 is manufactured. When the transducer 20 is completed, the transducer 20 is assembled into the case 10, and the molding material 41 is filled between the case 10 and the lower surface of the transducer 20 from a filling hole (not shown) of the case 10. Thus, the ultrasonic probe 1 is completed.

(Operation of ultrasonic probe and ultrasonic diagnostic equipment)
Next, operations of the ultrasonic probe and the ultrasonic diagnostic apparatus having the above-described configuration will be described.

  According to the ultrasonic probe having the above-described configuration, the hollow metal material 41 such as a carbon filler or a gold filler is mixed in the mold material 40 filled between the case 10 and the lower surface of the transducer 20.

  Therefore, it is possible to simultaneously realize a decrease in density of the molding material 40 and an increase in thermal conductivity. As a result, the weight of the ultrasonic probe 1 is reduced, the operability is improved, and the heat of the transducer 20 is efficiently radiated from the shield wire 53, and the temperature rise of the ultrasonic probe 1 is suppressed.

  Moreover, when the temperature rise of the ultrasonic probe 1 is suppressed, each material of the ultrasonic probe 1 becomes difficult to be thermally deteriorated, and it is possible to prevent a decrease in reliability and a decrease in quality. Furthermore, the transmission voltage that can be output within the range of the heat generation restriction becomes high, and a high-quality ultrasonic image with a good S / N ratio can be acquired. In addition, since it is only necessary to mix the hollow metal material 41 such as carbon filler or gold filler into the mold material 40, the structure of the ultrasonic probe 1 is not complicated.

  In the present embodiment, a spherical shell-like carbon filler, a gold filler, or the like is used as the hollow metal material 41. However, if the thermal conductivity is high and the hollow metal material 41 is hollow, a cylindrical shape as shown in FIG. Carbon fiber or gold fiber may be used.

  When carbon fiber, gold fiber, or the like is used as the hollow metal material 41, the mold material 40 does not flow into the hollow metal 41 if the inner diameter dimension is sufficiently small even if both ends thereof are open. Can contribute to lowering the density. Needless to say, the thermal conductivity.

  The application target of the present invention is not limited to a medical ultrasonic diagnostic apparatus, but may be applied to an ultrasonic flaw detection apparatus that images an internal state of a structure (subject) or the like.

  The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

1 is a schematic diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. The block diagram of the ultrasonic probe which concerns on the same embodiment. The perspective view of the transducer which concerns on the same embodiment. The enlarged view of the mold material which concerns on the same embodiment. The graph which shows the relationship between the mixing ratio of the hollow metal material which concerns on the same embodiment, and the thermal conductivity of a mold material. The graph which shows the relationship between the mixture ratio of the hollow metal material which concerns on the same embodiment, and the density of a mold material. Sectional drawing of the cable which concerns on the same embodiment. The enlarged view of the connection part of the case and cable which concern on the embodiment. The enlarged view of the mold material of the modification which concerns on the embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Ultrasonic probe, 2 ... Ultrasonic imaging device main body, 10 ... Case, 20 ... Transducer, 40 ... Mold material, 41 ... Hollow metal material, 50 ... Cable.

Claims (5)

A case gripped by an operator;
A transducer that is housed in the case and transmits / receives ultrasonic waves from the tip of the case to the subject; and
A cable connected to the base end of the case and transmitting and receiving electrical signals to and from the transducer;
Waterproof mold material filled between the case and the base end of the transducer;
Comprising
An ultrasonic probe, wherein a hollow metal material is mixed in the mold material.   The ultrasonic probe according to claim 1, wherein the hollow metal material is a carbon filler or a gold filler.   The ultrasonic probe according to claim 1, wherein the hollow metal material is carbon fiber or gold fiber.   The ultrasonic probe according to claim 1, wherein the mold material is in contact with a shield wire of the cable. In an ultrasonic imaging apparatus having an ultrasonic probe,
The ultrasonic probe is
A case gripped by an operator;
A transducer that is housed in the case and transmits / receives ultrasonic waves from the tip of the case to the subject; and
A cable connected to the base end of the case and transmitting and receiving electrical signals to and from the transducer;
Waterproof mold material filled between the case and the base end of the transducer;
Comprising
An ultrasonic imaging apparatus, wherein a hollow metal material is mixed in the mold material.

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