JP5480988B1 - Ultrasonic probe - Google Patents

Abstract

An ultrasonic probe for effectively exhausting heat from an internal unit to a probe head case is provided.
An internal unit (internal assembly) includes a vibrator unit, a relay board, an electronic circuit board, and a backing member. An exhaust heat sheet is bonded to the peripheral area on the back surface of the electronic circuit board 24. The waste heat sheet has a main body portion and a plurality of wings extending outward therefrom. Among the plurality of wings, a right wing 50 and a left wing 52 are included. Wings 50 and 52 are inserted into two slits 16 </ b> A formed in the probe head case (heat radiating shell) 16, and their end portions are bonded while being accommodated in two concave portions 16 </ b> B formed on the outer surface of the probe head case 16. Is done. Thereby, the heat generated inside the probe head case 16 can be directly transmitted to the outer surface of the probe head case 16.
[Selection] Figure 2

Description

  The present invention relates to an ultrasonic probe, and more particularly, to an intracavity ultrasonic probe having a two-dimensional array transducer.

  Ultrasound diagnostic apparatuses are used in the medical field. The ultrasonic diagnostic apparatus is an apparatus that transmits / receives ultrasonic waves to / from a living body and forms an ultrasonic image based on a reception signal obtained thereby. Ultrasonic wave transmission / reception is executed by an ultrasonic probe (probe). Various probes have been put into practical use, including an intracorporeal probe. The intracorporeal probe is inserted into the esophagus, rectum, vagina, etc., and transmits and receives ultrasonic waves in the body. Among them, the transesophageal probe is a probe inserted into the esophagus, and more specifically, a probe for transmitting and receiving ultrasonic waves to and from the heart in the esophagus.

  Recently, three-dimensional ultrasound diagnosis is becoming popular. This technology acquires volume data by transmitting and receiving ultrasonic waves to and from a three-dimensional space in a living body, and represents a three-dimensional image representing a three-dimensional space and an arbitrary cross section of the three-dimensional space based on the volume data. A two-dimensional tomographic image or the like is formed. In order to transmit and receive ultrasonic waves to and from the three-dimensional space, a two-dimensional array transducer is generally provided in the probe head. The two-dimensional array transducer is constituted by a plurality of vibration elements (for example, thousands of vibration elements) arranged two-dimensionally.

  Japanese Patent Application Laid-Open No. H10-228561 discloses a transphasic probe for three-dimensional ultrasonic diagnosis. A transducer unit is arranged in the head of the feeding probe, and the transducer unit is arranged in order from the living tissue side, a two-dimensional array transducer, an interface layer, an electronic circuit (integrated circuit), a backing A layer, a heat sink and the like. The electronic circuit is a circuit that performs channel reduction, that is, a circuit for reducing the number of signal lines. A heat sink is a circuit that takes away heat generated in an electronic circuit.

Japanese translation of PCT publication No. 2005-507581

  When an electronic circuit board is provided in the probe head, considerable heat is generated there, and exhaust heat from the electronic circuit board becomes a problem. That is, when the heat generated in the electronic circuit board is transmitted to the two-dimensional array transducer, the two-dimensional array transducer becomes high temperature, causing a problem of deterioration thereof, and a problem of increasing the temperature of the transmission / reception surface. Therefore, in order to prevent the heat generated in the electronic circuit board from being transmitted to the two-dimensional array transducer as much as possible, it is necessary to release the heat from the electronic circuit to another member.

  However, in the eclipse probe described in Patent Document 1, since the heat sink is provided on the back side of the electronic circuit board via the backing layer, it is difficult to increase the heat conduction efficiency from the electronic circuit board to the heat sink. The problem can be pointed out.

  An object of the present invention is to effectively release heat generated in the internal unit to other members.

  An ultrasonic probe according to the present invention includes an array transducer having a plurality of transducer elements and an electronic circuit provided on the back side of the array transducer and electrically connected to the plurality of transducer elements. An internal unit having an electronic circuit board; and a heat exhaust sheet for transferring heat from the electronic circuit board; and a probe head case containing the internal unit, wherein the heat exhaust sheet is from the electronic circuit board. A main body part that receives heat from the main body part, and a wing that extends heat from the main body part, the probe head case having an opening structure, and the wing The probe head case is joined to the opening structure while being inserted into the opening structure.

  According to the above configuration, the heat generated on the electronic circuit board in the internal unit (for example, the internal assembly or the internal laminate) can be transmitted to the probe head case via the heat exhaust sheet. The waste heat sheet has a main body portion and at least one wing, and heat received by the main body portion is transmitted to the wing, and further transmitted from the wing to the probe head case joined thereto. An opening structure is formed in the probe head case, and the opening structure has an opening communicating with at least the inside of the probe head case. A wing is inserted into the opening. The end of the wing is desirably pulled out to the outside of the probe head case, joined to the outer surface of the probe head case, or inserted into a gap formed inside the probe head case, that is, embedded. In general, in the probe head case containing the heating element, the temperature of the outer surface is lower than the inner surface thereof, so if the above-described heat exhaust sheet is used, the temperature is not passed through the inner surface of the probe head case. It is possible to transfer heat directly to the exterior or interior. That is, the temperature gradient can be positively utilized in exhaust heat. Of course, in addition to the above heat conduction, heat from the internal unit may be transmitted to the inner surface of the probe head case. Of the plurality of wings, some of the wings can be joined to the inner surface of the probe head. In any case, effective heat conduction to the portion having a lower temperature can effectively exhaust the electronic circuit board.

  The waste heat sheet is desirably joined directly or indirectly to the back surface of the electronic circuit board. In that case, it is desirable to form an opening through which a part of the backing member passes through the exhaust heat sheet so as to ensure the ultrasonic wave propagation from the electronic circuit board to the backing member. It is also possible to arrange the exhaust heat sheet on the front side (wave transmission / reception side) of the electronic circuit board. In any case, it is desirable to use a waste heat sheet having as good a thermal conductivity as possible.

  Desirably, at least the wing in the exhaust heat sheet has flexibility. According to this configuration, the assembly workability can be improved, and the wing can be easily adhered to the probe head case. When fixing the wing, it is desirable to use an adhesive having good thermal conductivity. Other fixing methods such as fitting, screwing, and welding may be employed.

  Preferably, the exhaust heat sheet has a right wing and a left wing extending from the main body portion to the right and left sides, the probe head case has a right opening structure and a left opening structure, and the right wing is the right opening. The left wing is fixed while being inserted into the left opening structure. According to this structure, since heat conduction can be performed using a plurality of wings, exhaust heat efficiency can be increased. In particular, since heat can be exhausted on both sides of the internal unit, the temperature rise of the electronic circuit board as a whole can be effectively suppressed. Normally, the width in the left-right direction is not so large inside the probe head case, so if heat is exhausted on the right and left sides of the electronic circuit board, the heat conduction distance from the electronic circuit board to the probe head case (outer surface or inside) Can be reduced.

  Preferably, the right side opening structure and the left side opening structure are a right side slit and a left side slit connected to the inside and the outside of the probe head case, and the right side wing is inserted into the right side slit and the outer surface of the probe head case The left wing is inserted into the left slit and fixed to the outer surface of the probe head case. According to this configuration, heat from the electronic circuit board is transmitted to the outer surface of the probe head through the right wing and the left wing, that is, through the right slit and the left slit. In the probe head case, the temperature of the outer surface is generally lower than the temperature of the inner surface facing the heating element, so heat can be released directly to such a low temperature portion, and the exhaust heat efficiency can be improved.

  Preferably, the outer surface of the probe head case is formed with a right recess connected to the right slit, the end of the right wing is accommodated in the right recess, and the outer surface of the probe head case is A left-side recess that is continuous with the left-side slit is formed, and an end of the left-side wing is accommodated in the left-side recess. According to this configuration, it is possible to eliminate or reduce the problem that the end portions of the probe head are greatly raised on the outer surface of the probe head and disturb the smoothness of the outer shape of the probe head. In particular, in an intracavity ultrasonic probe, it is strongly desired to smooth the shape of the probe head. However, according to the above configuration, such a request can be satisfied.

  Preferably, the wing is a first portion having a lateral width that can pass through the opening structure, and a deployable portion that is continuous with the first portion, and has a greater lateral width than the first portion in the deployed state. And a second portion fixed to the outer surface of the probe head case in the deployed state. According to this configuration, since the second portion is configured as a deployable portion, the second portion in the folded state is inserted into the opening structure, and then the second portion is set in the expanded state. The two parts can be fixed to the outer surface of the probe head. That is, the size (contact area) of the portion of the wing that contacts the outer surface of the probe head case can be increased regardless of the size of the opening structure.

  Preferably, the probe head case includes a first case portion and a second case portion, and the opening structure has a gap formed between the first case portion and the second case portion, and the wing Is inserted into the gap. According to this structure, it is possible to use both surfaces of a wing as a heat conductive surface. Further, it is possible to sandwich and fix the wing when the first case portion and the second case portion are joined.

  The above electronic circuit constitutes at least one of the transmission signal processing circuit and the reception signal processing circuit, and preferably constitutes both. The electronic circuit is preferably a channel reduction circuit. The channel reduction circuit generates a plurality of transmission drive signals from one transmission trigger signal in a whole unit or a predetermined unit at the time of transmission, and one group reception signal from a plurality of reception signals at a predetermined unit at the time of reception. Is generated. Preferably, the electronic circuit board is a semiconductor substrate that does not have a thick package with electronic circuits formed on the surface. Such an electronic circuit board may be directly bonded to the back side of the array transducer, but preferably the electronic circuit substrate is connected to the array transducer via a relay substrate. A relay board having a wiring conversion function or the like may be used. When the thermal conductivity of the exhaust heat member such as the exhaust heat sheet is higher than the thermal conductivity of the relay substrate, it is possible to more positively move the heat generated in the electronic circuit to the exhaust heat member. The array transducer is generally made of a piezoelectric material, but a so-called MUT (Micro-Machined Ultrasonic Transuducer) may be used. Preferably, the probe head case is a radiant body as well as a skeleton body of the probe head. It is composed of a member having a large surface area and good thermal conductivity. If such a heat dissipation structure is used, the temperature rise of the electronic circuit board can be suppressed without causing a local temperature rise by radiating heat from the whole to the surroundings. The ultrasonic probe is preferably an intracorporeal probe, and particularly preferably a food probe having a 2D array transducer.

According to the present invention, it is possible to effectively escape gas heat generated by the internal unit to another member. Thereby, the temperature rise in the array transducer can be suppressed.

It is XZ sectional drawing which shows suitable embodiment of the body cavity insertion type probe which concerns on this invention. It is YZ sectional drawing of the probe shown in FIG. It is a perspective view which shows the thermal radiation shell which comprises a probe head case. It is a figure which shows an example of a vibrator | oscillator unit. It is a figure which shows the structural example of a transmission / reception circuit. It is a flowchart which shows an example of the probe manufacturing method which concerns on this invention. It is a figure for demonstrating adhesion | attachment of the waste heat sheet to a main laminated body. It is a figure for demonstrating backing and adhesion | attachment of a case. It is a figure which shows the convex part provided in backing. It is a figure for demonstrating bending and adhesion | attachment of the front-back wing. It is a figure for demonstrating the bending of a front side flexible substrate. It is a figure which shows the backing and heat exhaust member which concern on other embodiment. It is a figure which shows the relationship between a transmission / reception area | region and a backing member joining area | region. It is a figure which shows the 2nd example of the wing fixing method. It is a figure which shows the 3rd example of the wing fixing method.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 shows a preferred embodiment of an ultrasonic probe according to the present invention, and FIG. 1 is a sectional view (XZ sectional view) thereof. This ultrasonic probe is a body cavity insertion type probe, in particular, a transphasic probe.

  In FIG. 1, a probe 10 includes a probe head 12, an insertion tube 13, an operation unit, a probe cable, and the like. In this embodiment, the probe head 12 is a part that is inserted into an esophagus in a living body and transmits and receives ultrasonic waves in the esophagus. The probe head 12 is positioned so that the test site in the heart is taken into the three-dimensional space as the ultrasonic wave transmission / reception region.

  The interior of the probe head 12 is a cavity in which an internal assembly 14 is disposed. You may make it fill the inside with fillers, such as resin. The internal assembly 14 transmits and receives ultrasonic waves in the Z direction, that is, downward in FIG. Incidentally, the X direction is the central axis direction of the probe head 12, the Z direction is the transmission / reception direction, and the Y direction is defined as a direction orthogonal to the X direction and the Z direction. Specifically, the internal assembly 14 is disposed inside the heat dissipation shell 16. The heat radiating shell 16 is a hollow hard container made of a heat conducting member such as copper, which constitutes a probe head case. In other words, the heat radiating shell 16 constitutes an exoskeleton or a structure in the probe head 12. A relatively soft outer skin 18 is provided outside the heat radiating shell 16, and the outer skin 18 is made of an insulating resin or the like. An opening 16 </ b> D is formed on the living tissue side of the heat radiating shell 16, and a part of the inner assembly 14 protrudes outside the heat radiating shell 16 through the opening 16 </ b> D. The internal assembly 14 includes a vibrator unit 20, a relay board 22, an electronic circuit board 24, a backing member 26, a heat exhaust sheet having a plurality of wings, a backing case 33, and the like, as will be described below. Below, those members are explained in full detail.

  As will be described later with reference to FIG. 4, the array transducer is composed of a plurality of vibration elements arranged in the X direction and the Y direction, and specifically includes thousands of vibration elements. An ultrasonic beam is formed by such an array transducer, and the ultrasonic beam is electronically scanned. As an electronic scanning method, an electronic sector scanning method or the like is known. In this embodiment, an ultrasonic beam can be scanned in a two-dimensional direction, and a three-dimensional space is configured by such scanning. It is possible to form a three-dimensional ultrasonic image or the like representing the three-dimensional space by processing the volume data acquired from the three-dimensional space. As shown in FIG. 1, an opening 18A is formed on the living body side of the outer skin 18, and a part of the vibrator unit 20 on the living body side swells from the opening 18A to the living body side. When performing the ultrasonic diagnosis, a state is formed in which the living body side surface of the transducer unit 20, that is, the wave transmitting / receiving surface is in close contact with the inner surface of the esophagus as the living tissue surface.

  A relay substrate 22 is provided on the back side of the vibration unit 20, that is, on the upper side in FIG. 1. The relay substrate 22 has a function of electrically connecting the array transducer and the electronic circuit formed on the electronic circuit substrate 24. In the present embodiment, the relay substrate 22 is configured by a multilayer substrate and has a lead array 40. The lead array 40 electrically connects a plurality of vibration elements and a plurality of terminals on the electronic circuit. The relay substrate 22 may be an interposer having an array conversion function. That is, the electrode arrangement on the array transducer side and the electrode arrangement on the electronic circuit side can be different. In this embodiment, the relay board 22 also has a function of connecting the flexible boards 36 and 38 to be described later and an electronic circuit. For this purpose, connection line groups 42 and 44 are provided in the relay board 22. ing. As shown in FIG. 1, the relay substrate 22 is installed in an opening 16 </ b> D formed in the heat dissipation shell 16. The base material of the relay substrate 22 is, for example, an insulating ceramic.

  An electronic circuit board 24 is provided on the back side of the relay board 22, that is, on the upper side in FIG. The electronic circuit board 24 includes an electronic circuit for channel reduction. That is, at the time of transmission, the electronic circuit generates a plurality of transmission drive signals based on the transmission trigger signal sent from the apparatus main body side in the whole array vibrator or in a predetermined unit, and supplies them to the array vibrator. In addition, at the time of reception, the circuit generates a group reception signal by performing phasing addition processing on a plurality of reception signals in element group units. By providing such a channel reduction circuit, the number of signal lines connected to the probe head can be greatly reduced. For example, it is possible to process signals of all the vibration elements by simply connecting about 100 signal lines to thousands of vibration elements. In the present embodiment, the electronic circuit board 24 is constituted by a substantially bare semiconductor substrate having an electronic circuit formed on the surface thereof. That is, no package as an exterior is provided, and the entire semiconductor substrate is protected by a thin protective layer. A plurality of electrodes corresponding to the plurality of vibration elements are formed on the living body side surface 24 </ b> A of the electronic circuit board 24. The lead array 40 described above is connected to them. The thickness of the electronic circuit board 24 in the Z direction is, for example, about 0.6 mm. Incidentally, the thickness of the relay board 22 in the Z direction is about 1 mm, for example.

  On the back surface 24B of the electronic circuit board 24, an ultrasonic wave propagation region as a central region and a heat exhaust region as a peripheral region are set. A backing member 26 is bonded to the ultrasonic wave propagation region. Specifically, the backing member 26 is configured by a block-shaped main body 48 and a convex portion 46 provided on the living body side thereof, and the living body side surface of the convex portion 46 is joined to the ultrasonic wave propagation region. An exhaust heat sheet is bonded to the peripheral area as will be described in detail later. More specifically, the exhaust heat sheet has an opening, and the convex portion 46 is joined to the central portion on the back side of the electronic circuit board 24 through the opening, thereby the periphery of the main body 48 of the backing member 26 and the electronic circuit board 24. An exhaust heat sheet is sandwiched between the exhaust heat area as an area. The waste heat sheet has a rear wing 30 and a front wing 32 shown in FIG. In addition, it has a right wing and a left wing, which are not shown in FIG. The backing member 26 scatters and attenuates unnecessary ultrasonic waves radiated to the back side. For example, the acoustic attenuation characteristic of the backing member 26 is about 6 to 15 dB / cm MHz.

  The backing member is configured, for example, as a mixture of tungsten, a tungsten compound, or the like with respect to the resin. In this case, examples of the resin include thermoplastic resins such as nylon, polyethylene, polypropylene, and polystyrene, and also include thermosetting resins such as epoxy resins, phenol resins, urea resins, and melanin resins. Furthermore, various rubbers can be mentioned. In the production, an appropriate amount of powder of tungsten, tungsten compound, or the like is mixed into the resin in order to realize a desired acoustic impedance and desired acoustic attenuation characteristics. Of course, other materials may be mixed.

  The exhaust heat sheet described above is constituted by, for example, a carbon sheet, a graphite sheet, a sheet made of a metal such as copper, or the like, and in any case, is constituted by a material having a good thermal conductivity. The thickness of the backing member 26 in the Z direction is, for example, about 3 mm.

  The backing member 26 is wrapped by a backing case 33 except for the living body side end. That is, the main body 48 of the backing member 26 is accommodated in the backing case 33. The backing case 33 functions as a heat conduction member and a jig. In the present embodiment, the rear wing 30 and the front wing 32 of the exhaust heat sheet are bent along the outer surface of the backing case 33 and bonded to the outer surface of the backing case 33. Therefore, heat moves from the back side of the electronic circuit board 24 to the backing case 33 via the rear wing 30 and the front wing 32. The backing case 33 is bonded and fixed to the heat radiating shell 16 as shown in FIG. 2 below, and heat conduction occurs from the backing case 33 to the heat radiating shell 16. At the same time, the backing case 33 is held and fixed in the probe head 12 by the heat radiating shell 16. In addition to the above, heat is transferred from the back side of the electronic circuit board 24 to the heat radiating shell 16 through the right wing and the left wing of the heat exhaust sheet as will be described in detail later.

  Flexible substrates 36 and 38 are connected to both ends of the back side of the relay substrate 22, that is, the non-biological side. Each of the flexible boards 36 and 38 is made of FPC and has a wiring pattern. A plurality of signal lines are connected to the ends of the flexible substrates 36 and 38 on the apparatus main body side. However, those signal lines are not shown in FIG. A plurality of signal lines may be connected to the flexible boards 36 and 38 using a connector. As shown in FIG. 2, in the heat radiating shell 16, slits 16 </ b> A are formed on both side surfaces in the Y direction. A right wing and a left wing described later are inserted into the two slits 16A. In the present embodiment, the flexible substrate 38 is provided in addition to the flexible substrate 36 in order to ensure connection to a large number of signal lines. As shown in FIG. 1, the flexible board 38 extends upward from the front end edge of the relay board 22 and passes through the back side of the internal assembly 14, that is, the upper side in FIG. 1, and is then drawn out to the apparatus main body side. . Of course, as long as the connection of a plurality of signal lines can be reliably performed, the flexible substrate 38 can be omitted.

  FIG. 2 shows a cross section in the direction indicated by II in FIG. 1, that is, a YZ cross section. As already described, the probe head 12 has the heat dissipation shell 16. The heat radiating shell 16 functions as a heat conductor, that is, a heat radiating body, and also functions as a probe head case. The heat radiating shell 16 is covered with an outer skin 18. An internal assembly 14 is provided inside the probe head 12. The internal assembly 14 includes the transducer unit 20, the relay board 22, the electronic circuit board 24, the backing member 26, and the backing case 33 that are provided in order from the living body side. have. An exhaust heat sheet is sandwiched between the electronic circuit board 24 and the backing member 26. The waste heat sheet is composed of a main body portion 77 as a heat receiving portion and a plurality of wings connected thereto. Specifically, the plurality of wings include the above-described rear wing and front wing, and the right wing 50 and the left wing 52 shown in FIG. The right wing 50 and the left wing 52 are inserted into a pair of slits 16 </ b> A formed on the left and right side walls of the heat dissipation shell 16. Each slit 16A is a through groove extending in the X direction. The main body portion 77 in the heat exhaust sheet is a portion sandwiched between the electronic circuit board 24 and the backing member 26, and the front surface of the main body portion 77 is joined to a peripheral region on the back surface of the electronic circuit board 24. The right wing 50 and the left wing 52 are configured by first portions 50a and 52a that are connected to the main body portion 77 and pass through the slit 16A, and second portions 50b and 52b that are connected to the main portion 77 and vertically rise. The second portions 50 b and 52 b are bent and bonded onto the outer surface of the heat dissipation shell 16. Specifically, a pair of recesses 16B are formed on the outer wall surface of the heat dissipation shell 16, and a pair of second portions 50b and 52b are accommodated and fixed therein. Therefore, the heat generated in the electronic circuit board 24 is directly transmitted to the outer surface of the heat radiating shell 16 through the right wing 50 and the left wing 52. The depth of each recess 16B corresponds to the sum of the thickness of each wing 50, 52 and the thickness of the adhesive. In a state where the second portions 50b and 52b are accommodated in the concave portions 16B, a flush state is formed. It should be noted that an adhesive mixed with a heat conductive filler may be used in order to improve the heat conductivity when bonding the members. Or you may make it apply | coat the grease with heat conductivity with respect to a joint surface.

  A pair of recesses 16C are formed on both sides in the Y direction on the inner surface of the heat dissipation shell 16, and both ends of the backing case 33 are inserted into the recesses 16C. That is, the backing case 33 is held and fixed by the heat radiating shell 16. Since the backing case 33 is fixed by the heat radiating shell 16 and the right wing 50 and the left wing 52 are fixed to the heat radiating shell 16, the internal assembly 14 is securely fixed to the heat radiating shell 16. . As described above, the exhaust heat sheet has the rear wing 30 and the front wing 32, which are joined and fixed to the backing case 33, which also exerts the fixing action of the internal assembly 14.

  FIG. 3 is a perspective view of the heat dissipation shell 16 described above. The heat radiating shell 16 is divided into two in the left-right direction, that is, it is constituted by a right side portion 16-1 and a left side portion 16-2. As described above, the slit 16A is formed on the right side surface and the left side surface of the heat radiating shell 16, and the right wing and the left wing are inserted into each slit 16A, and they are fixed in a bent state. In FIG. 3, the second portion 52b in the left wing is shown. As shown in FIG. 3, the heat radiating shell 16 constitutes a structure as an exoskeleton, that is, it has a very large surface area. Therefore, if the heat generated in the electronic circuit is transmitted to the heat dissipation shell 16, the heat dissipation shell 16 as a whole can be effectively released to the outside. The external environment in that case includes the periphery of the probe head through the outer skin, and also includes an insertion tube and a large number of signal lines inserted through the inside thereof. With such a configuration, the temperature rise of the electronic circuit board can be effectively suppressed by absorbing the generated heat with a large member and releasing it with a large area while avoiding a local temperature rise. As a result, it is possible to effectively suppress the temperature rise of the array transducer and the transmission / reception surface. In particular, in this embodiment, the heat radiating shell 16 functions as a fixing member for the internal assembly 14, that is, the connecting structure for fixing can be used as the heat exhausting structure, so that an advantage is obtained from the viewpoint of the number of parts. It is done.

  FIG. 4 shows a specific example of the vibrator unit 20 shown in FIG. In FIG. 4, the upper side of the drawing is the living body side. The array transducer 54 includes a plurality of vibration elements 54a arranged in the X direction and the Y direction. The array vibrator 54 is made of, for example, a material such as PZT, crystal, zinc oxide, or a composite material containing such a piezoelectric material. The array transducer may be configured by a MUT. The thickness of each vibration element 54a in the Z direction is set to about ¼λ with respect to the center frequency of the ultrasonic wave.

  A conductive resonance layer 62 is provided on the back side of the array transducer 54. The conductive resonance layer 62 includes a plurality of conductive resonance elements 62a arranged in the X direction and the Y direction. The conductive resonance layer 62 assists ultrasonic wave transmission / reception in the array transducer 54. It is made of a conductive material, for example, a composite containing cobalt, zirconia, tungsten compound and the like. Of course, any of the materials listed herein is just an example. The acoustic impedance of the array transducer 54 is, for example, about 30 MRayls, whereas the acoustic impedance of the conductive resonance layer 62 is, for example, 70 to 100 MRayls. That is, in the present embodiment, the conductive resonance layer 62 constitutes a hard back layer, and the array transducer 54 and the conductive resonance layer 62 are integrated to transmit and receive ultrasonic waves. The conductive resonance layer 62 also exhibits an electrical connection effect between the array transducer 54 and the relay substrate. Incidentally, a thin metal foil constituting an electrode is provided on the upper surface and the lower surface of each vibration element 54a, which is made of, for example, gold or silver.

  For reference, the acoustic impedance of each member on the back side of the array transducer 54 will be described. The acoustic impedance of the relay board shown in FIG. 1 and the like is about 19 MRayls, for example, and the acoustic impedance of the electronic circuit board is, for example, It is about 17MRayls. That is, the relay board and the electronic circuit board have substantially the same acoustic impedance, and reflection of ultrasonic waves at the boundary surface between them is prevented as much as possible. The acoustic impedance of the backing member is, for example, 15 to 25 MRayls. With such a setting, reflection of ultrasonic waves at the interface between the electronic circuit board and the backing member is prevented as much as possible. As a result, the ultrasonic waves emitted from the back side of the array transducer and the conductive resonance layer naturally reach the backing member via the relay substrate and the electronic circuit board. Ultrasound is effectively attenuated and absorbed. Even if reflection occurs on the back surface of the backing member 26, the reflected wave is also effectively attenuated and absorbed in the backing member. Therefore, for example, when the ultrasonic probe is left in the air, it is possible to effectively prevent the problem of multiple reflection that occurs between the transmission / reception surface and the back surface of the backing member. Of course, even during normal ultrasonic diagnosis, it is possible to effectively absorb unnecessary ultrasonic waves emitted to the back side and improve image quality.

  Returning to FIG. 4, the first matching layer 56 and the second matching layer 58 are provided on the living body side of the array transducer 54. The first matching layer 56 is composed of a plurality of matching elements 56a arranged two-dimensionally, and the second matching layer 58 is composed of a plurality of matching elements 58a arranged two-dimensionally. A protective layer 60 is provided on the living body side of the second matching layer 58. The surface on the living body side constitutes the wave transmitting / receiving surface. Reference numeral 64 denotes a separation groove formed between adjacent elements, and the separation groove 64 may be an air layer, but in this embodiment, silicone rubber that exhibits acoustic insulation in the separation groove 64. Etc. are filled.

  FIG. 5 shows a configuration example of the electronic circuit 25 included in the electronic circuit board. The array transducer 54 is constituted by a plurality of vibration elements 54a arranged two-dimensionally as described above. In the present embodiment, a plurality of groups 66 are set for the array transducer 54, and each group 66 is constituted by a plurality of vibration elements that gather together with a predetermined shape. The electronic circuit 25 includes a transmission signal processing circuit 70 and a reception signal processing circuit 68. The transmission signal processing circuit 70 generates a plurality of transmission drive signals to be supplied to the plurality of vibration elements based on a transmission control signal (including a transmission trigger signal) from the apparatus main body side. One transmission signal processing circuit 70 may be provided for the entire array transducer 54, or a transmission signal processing circuit 70 may be provided for each group 66. In any case, the transmission signal processing circuit 70 generates a plurality of transmission drive signals from one transmission control signal, and realizes processing corresponding to channel reduction at the time of transmission.

  In the present embodiment, the reception signal processing circuit 68 includes a plurality of sub beam formers (SBFs) 72 corresponding to the plurality of groups 66. Each SBF 72 performs phasing addition processing (sub phasing addition processing) on a plurality of reception signals output from the corresponding group 66, thereby generating a group reception signal after phasing addition. . A plurality of group reception signals are generated by such processing, and main phasing addition processing is performed on them by the main beam former (MBF) 74, whereby beam data after phasing addition corresponding to the reception beam is performed. Is generated. Here, the MBF 74 is provided in the apparatus main body. Each SBF 72 performs channel reduction at the time of reception. In the present embodiment, for example, one group reception signal is generated by performing phasing addition processing on 16 reception signals.

  Since heat is generated in the process of transmitting / receiving signal processing as described above, the temperature of the electronic circuit board rises and the temperature of the array transducer and the transmission / reception surface rises accordingly unless the heat treatment is effectively performed. End up. On the other hand, in the present embodiment, heat is dissipated by the heat treatment described above, that is, by transferring heat from the electronic circuit board to the heat radiating shell via the heat radiating sheet (and the backing case), and the heat radiating shell as a whole. As a result, it is possible to effectively release the heat generated in the electronic circuit board to the outside.

  Next, an example of the operation of the probe shown in FIG. The probe head 12 shown in FIG. 1 is inserted into the esophagus from the mouth of the subject, and the probe head 12 is positioned at a predetermined position in the esophagus. Thereby, the transmission / reception surface of the probe head 12 is closely attached to the inner wall surface of the esophagus. By executing ultrasonic transmission / reception in that state, specifically, by executing a two-dimensional scan of the ultrasonic beam, a three-dimensional region including the measurement site in the heart is formed and corresponds to the three-dimensional region. Volume data to be obtained can be obtained. An ultrasonic three-dimensional image representing a three-dimensional space is formed based on such volume data, or an arbitrary tomographic image representing an arbitrary cross section in the three-dimensional space or a triplane image representing a plurality of predetermined cross sections is created. It will be.

  More specifically, at the time of transmission, a transmission signal is supplied from the apparatus main body side to the probe head 12 via a cable. The transmission signal is sent to the electronic circuit via the flexible board 36 or the flexible board 38 and also via the relay board 22. Then, a plurality of transmission drive signals are generated based on a single transmission signal by the transmission signal processing circuit in the electronic circuit, and these are supplied to the corresponding plurality of vibration elements. In that case, a plurality of transmission drive signals are sent to the array transducer via the lead array formed on the relay substrate described above. By supplying such a plurality of transmission driving signals, a transmission beam is formed in the array transducer. At that time, when unnecessary ultrasonic waves are emitted to the back side of the array transducer, such unnecessary ultrasonic waves are effectively absorbed and reduced by the backing member 26.

  On the other hand, when a reflected wave from the living body is received by the array transducer during reception, a plurality of received signals are sent from the array transducer to the electronic circuit via the lead array 40 in the relay substrate 22. . In the reception signal processing unit in the electronic circuit, sub phasing addition processing is performed on a plurality of reception signals for each group, thereby generating a group reception signal. The plurality of group reception signals thus generated are transmitted to the plurality of signal lines via the flexible substrate 36 and the flexible substrate 38, and further transmitted to the apparatus main body. In the apparatus main body, main phasing and addition processing is executed based on a plurality of group reception signals, thereby generating beam data corresponding to the reception beam. Incidentally, even if a reflected wave appears on the back side of the array transducer during reception, such unnecessary ultrasonic waves are effectively reduced at the backing member 26.

  Next, the thermal action will be described. Heat generated in the electronic circuit by transmission / reception signal processing or the like is transmitted to the heat radiating shell 16 through a heat exhaust sheet joined to the back side of the electronic circuit board 24. Specifically, the heat transmitted to the rear wing 30 and the front wing 32 in the exhaust heat sheet is transmitted to the heat radiating shell 16 via the backing case 33. On the other hand, the heat transmitted to the right wing and the left wing of the exhaust heat sheet is directly transmitted to the outer surface of the heat radiating shell 16. Thus, heat can be effectively transferred to the heat radiating shell 16 via the four wings, and the heat radiating shell 16 is configured as a member having a very large heat capacity, and its surface area is also large. Since it is very large, it is possible to effectively dissipate the transmitted heat to the outside, and it is possible to prevent local heat generation.

  In this embodiment, the thermal conductivity of the electronic circuit board 24 and the exhaust heat sheet is higher than the thermal conductivity of the relay board 22, and most of the heat generated in the electronic circuit board is exhausted. It will be transmitted to the heat sheet. Conversely, the relay substrate exhibits a kind of thermal isolation action, and even if there is heat conduction by the lead array 40, heat conduction to the array transducer via the relay substrate 22 is suppressed. .

  In the present embodiment, as described above, the backing member 26 is joined to the central portion of the back surface of the electronic circuit board 24, and the exhaust heat sheet is joined to the peripheral region on the back surface. As a result, it is possible to effectively absorb unnecessary ultrasonic waves by applying a backing action by the backing member to a part where ultrasonic waves are more likely to propagate. On the other hand, heat conduction similar to that in the central region occurs in the peripheral region, and heat can be effectively taken away from the peripheral region via the exhaust heat sheet. That is, it is possible to achieve both absorption of unnecessary ultrasonic waves and exhaust heat for suppressing heat generation on the back side of the electronic circuit board. In particular, in the above embodiment, the backing member 26 is accommodated by the backing case 33, and the backing case 33 is wrapped by the rear wing 30 and the front wing 32. An exoskeleton can be constructed and the entire internal assembly 14 can be secured by holding the backing member 26. As a result, it is not necessary to firmly hold the internal assembly 14 on the living body side. Of course, other holding methods may be employed as needed to hold the internal assembly 14.

  Next, a method for manufacturing the probe shown in FIG. 1 will be described with reference to FIGS.

  In S10 in FIG. 6, the main laminate 75 shown in FIG. 7 is manufactured. That is, the main laminate 75 including the vibrator unit 20, the relay substrate 22, and the electronic circuit substrate 24 is configured. Flexible boards 36 and 38 are attached to the relay board 22.

  In S <b> 12 of FIG. 6, as shown in FIG. 7, the exhaust heat sheet 76 is bonded to the main laminate 75. The exhaust heat sheet 76 includes a main body portion 77 having an opening 78 and a plurality of wings connected thereto. The plurality of wings includes a rear wing 30 and a front wing 32 arranged in the X direction, and a right wing 50 and a left wing 52 arranged in the Y direction. Reference numeral 77A denotes an area corresponding to a peripheral region on the back surface of the electronic circuit board 24. Of course, the form of the exhaust heat sheet 76 is not limited to that shown in FIG.

  In S <b> 14 in FIG. 6, the backing member and the backing case are bonded to the main laminate after the exhaust heat sheet is bonded. Specifically, as shown in FIG. 8, the joined body 80 is joined onto the heat exhaust sheet 76. The combined body 80 includes the backing member 26 and a backing case 33 that accommodates the backing member 26. FIG. 9 shows a state in which the combined body 80 is turned over, and a convex portion 46 is formed at the living body side central portion of the backing member 26. The combined body is bonded onto the heat removal sheet so that the convex portion 46 fits into the opening 78 shown in FIG.

  In S16 shown in FIG. 6, as shown in FIG. 10, the rear wing 30 and the front wing 32 are bent and fixed to the back side of the backing case 33, that is, the upper side in FIG. Thereby, the backing case 33 and the exhaust heat sheet 76 are integrated.

  In S20 of FIG. 6, as shown in FIG. 11, the front flexible substrate 38 is bent. Specifically, the front flexible substrate 38 is bent so as to pass the non-living side of the backing case 33.

  In S22 of FIG. 6, the assembly shown in FIG. 11 is disposed in the heat dissipation shell. Specifically, the heat radiating shell is assembled so that the right wing and the left wing come out from the pair of slits at the same time so that the backing case is sandwiched between the two divided parts, and the internal assembly is placed inside the shell at the same time. Is done. And in S24 of FIG. 6, the part which protruded from the slit in a right wing and a left wing is bend | folded, and the part is adhere | attached and fixed with respect to the thermal radiation shell. In S26 of FIG. 6, the wiring process, the formation of the outer skin on the outer side of the heat radiating shell, and the like are carried out, thereby forming the probe shown in FIG.

  As is clear from the above description, the rear wing and the front wing of the exhaust heat sheet exert a fixing action of the backing case, that is, the backing member, and the right wing and the left wing of the exhaust heat sheet sandwich the backing case. The heat wrapping shell is further wrapping from the outside. As a result of such multiple wrapping action, the internal assembly is firmly fixed to the heat radiating shell. A reliable heat conduction route to will be established.

  FIG. 12 shows another embodiment. In the example shown in FIG. 12, the heat removal member 82 is configured as a block-shaped member, and an opening 84 is formed at the center thereof. A backing member 86 is inserted and fixed in the opening 84. Such a composite is bonded to the back side of the electronic circuit board.

  Also in such an embodiment, the backing member 86 can be bonded to the central portion on the back side of the electronic circuit board, that is, the portion where ultrasonic wave propagation is most likely to occur, and the heat exhaust member 82 is bonded to the peripheral portion thereof. Therefore, sufficient heat absorption can be performed by the exhaust heat member 82. That is, according to this configuration, it is possible to achieve both the absorption of ultrasonic waves and the exhaust heat action.

  FIG. 13 shows a two-dimensional region 88 corresponding to the array transducer. Reference numeral 90 denotes an effective area that is actually used for transmission and reception, which is a circular area. In setting the region to which the backing member is joined, it is desirable that the region is 50% or more of the entire region of the array transducer, specifically, the central region. In particular, as shown in FIG. 13, it is desirable to set the backing area as an area 92 that is inscribed in or equivalent to the effective area 90 that is actually used in transmission and reception. According to such a configuration, it is possible to obtain a backing action almost uniformly over the entire array transducer.

  Although the probe in the above-described embodiment is a phagocytic probe, the above-described configuration can be applied to other intra-body-cavity insertion-type probes, and can also be applied to probes other than the intra-body-cavity insertion-type probes. Is possible.

  In the above embodiment, the heat generated in the electronic circuit board can be directly transmitted to the outer surface of the probe head case via the heat exhaust sheet. Since the heating element is present in the probe head case, the temperature of the outer surface is lower than the temperature of the inner surface. Therefore, if heat is exhausted to such an outer surface, the heat gradient can be fully utilized and the heat exhaust efficiency can be increased. Thereby, the temperature rise of the array transducer can be prevented or alleviated.

  14 and 15 show a second example and a third example of the wing fixing method. In the second and third examples, similar to the first example shown in FIG. 2, the heat generated in the electronic circuit board is released to the probe head case as a heat radiating shell using a heat exhaust sheet.

  FIG. 14 shows a second example of the wing fixing method. In the second example, an internal unit 202 as an internal assembly is accommodated in a hollow probe head case 200. The internal unit 202 is a laminate including an array vibrator, an electronic circuit board, a heat exhaust sheet, and the like. The waste heat sheet is composed of a main body portion joined to the back surface of the electronic circuit board and a plurality of wings drawn from the main body portion. The plurality of wings include a left wing 204 and a right wing not shown. Since the right wing has the same shape as the left wing 204 and is fixed in the same manner as the left wing 204, the configuration and the fixing method thereof will be described below by taking the left wing 204 as a representative.

  FIG. 14 shows a fixed state of the left wing 204. The left wing 204 has a first portion 206 that passes through the slit 200A, and a second portion 208 that serves as a lead-out portion (or an end portion) connected to the first portion 206. The lateral width of the first portion 206 is smaller than the lateral width of the slit 200A. The second portion 208 can be deformed from the folded state to the expanded state. The second portion 208 includes a rectangular portion 208a and both end portions 208b provided at both ends thereof. Both end portions 208b are foldable portions. The lateral width of the rectangular portion 208 a is the same as the lateral width of the first portion 206. When the second portion 208 passes through the slit 200A, the second portion 208 is folded. As a result, the second portion 208 can easily pass through the slit 200A. After the second portion 208 passes through the slit 200A, the second portion 208 is in a deployed state. In such an unfolded state, the lateral width of the second portion 208 is larger than the lateral width of the slit 200A. The second portion 208 in the unfolded state is adhesively fixed to the outer surface of the probe head case. A concave portion may be formed on the outer surface of the probe head case according to the shape of the second portion 208. The second portion of the right wing can also change from the folded state to the expanded state, and the second portion is bonded and fixed on the outer surface of the probe head case in the expanded state. Reference numeral 210 denotes a fold line. Reference numeral 201 denotes an outer skin.

  According to the second example shown in FIG. 14, the joint portion to the probe head case in the wing can be made larger, so that the efficiency of heat conduction can be increased. In particular, there is an advantage that it is not necessary to unnecessarily increase the lateral width of the slit. Various shapes can be employed as the shape of the second portion 208. For example, you may make it comprise the 2nd part expand | deployed in the up-down both directions on the outer surface of a probe head case.

  FIG. 15 shows a third example of the wing fixing method. The probe head case 220 includes an upper case 222 and a lower case 224, which are combined in the vertical direction (Z direction). Opening structures 226 and 229 are formed on the right side and the left side across the upper case 222 and the lower case 224. Since the opening structures 226 and 229 have symmetrical structures, the opening structure 226 will be described below as a representative.

  The opening structure 226 includes a horizontal groove 227 that communicates with the inside of the probe head case 220 and a vertical groove 228 that communicates with the horizontal groove. The horizontal groove 227 has an entrance opening, and the back side forms a gap from the entrance opening. The internal unit 232 disposed in the probe head case 220 includes an array transducer, an electronic circuit board, a heat exhaust sheet 236, and the like. The heat exhaust sheet 236 has a main body portion and a plurality of wings drawn therefrom, and the plurality of wings include a right wing 238 and a left wing 240. They are flexible. In FIG. 15, the right wing 238 is inserted into the opening structure 226. The right wing 238 includes a first portion (horizontal portion) 238a continuous with the main body portion and a second portion (vertical portion) 238b continuous therewith. The first portion 238 a is inserted into the horizontal groove 227, and the second portion is inserted into the vertical groove 228. In such an inserted state, the right wing 238 is nipped and fixed by the upper case 222 and the lower case 224. Similarly, the left wing 240 is inserted into the opening structure 229, and is sandwiched and fixed by the upper case 222 and the lower case 224.

  According to the configuration shown in FIG. 15, heat generated in the electronic circuit board can be transferred to the inside of the probe head case 220 through the two wings inserted in the thickness of the probe head case 220. . In the probe head case 220, since a temperature drop is generally observed from the inner surface to the outer surface, it is preferable to conduct heat to a portion other than the inner surface than to conduct heat to the inner surface. According to the configuration shown in FIG. 15, heat conduction can be performed to the inside where a temperature decrease is expected from the inner surface. In addition, both sides of the wing can be brought into contact with the probe head case 220. Therefore, effective exhaust heat can be performed. Moreover, it is possible to sandwich the two wings when the upper case 222 and the lower case 224 are coupled, and the two wings can be fixed easily. But you may make it fix those wings using an adhesive agent etc. In FIG. 15, each wing is bent upward (non-biological side), but each wing may be bent downward (biological side). If heat is exhausted on the right and left sides of the internal unit, the distance from the heating element to the heat radiating body can be shortened, and the advantage that the efficiency of exhaust heat can be improved is obtained.

  10 probe, 12 probe head, 14 internal assembly, 16 heat dissipation shell, 18 outer skin, 20 transducer unit, 22 relay board, 24 electronic circuit board, 26 backing member, 30 rear wing, 32 front wing, 33 backing case, 50 right Wing, 52 Left wing.

Claims (7)

An electronic circuit board including an array vibrator having a plurality of vibration elements, an electronic circuit provided on a back side of the array vibrator and electrically connected to the plurality of vibration elements, and from the electronic circuit board An internal unit having an exhaust heat sheet for transferring heat;
A probe head case containing the internal unit;
Including
The waste heat sheet is
A body portion that receives heat from the electronic circuit board;
A portion through which heat from the main body portion is transmitted, the wing extending outward from the main body portion, and
The probe head case has an opening structure,
The wing was inserted into the opening structure and joined to the probe head case,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1,
At least the wing in the waste heat sheet has flexibility,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1,
The waste heat sheet has a right wing and a left wing extending from the main body part to the right and left sides,
The probe head case has a right side opening structure and a left side opening structure,
The right wing is fixed while being inserted into the right opening structure,
The left wing is fixed while being inserted into the left opening structure,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 3,
The right side opening structure and the left side opening structure are a right side slit and a left side slit connected to the inside and the outside of the probe head case,
The right wing is inserted into the right slit and fixed to the outer surface of the probe head case;
The left wing was inserted into the left slit and fixed to the outer surface of the probe head case;
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 4,
On the outer surface of the probe head case, a right concave portion connected to the right slit is formed, and an end portion of the right wing is accommodated in the right concave portion,
On the outer surface of the probe head case, a left-side recess connected to the left-side slit is formed, and an end of the left wing is accommodated in the left-side recess.
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1,
The wing is
A first portion having a lateral width capable of passing through the opening structure;
A deployable portion that is continuous with the first portion, and has a larger lateral width than the first portion in the deployed state, and is fixed to the outer surface of the probe head case in the deployed state;
Ultrasonic probe characterized by including. The ultrasonic probe according to claim 1,
The probe head case is composed of a first case portion and a second case portion,
The opening structure has a gap formed between the first case portion and the second case portion,
The wing was inserted into the gap,
An ultrasonic probe characterized by that.

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