JP6840642B2 - Ultrasonic probe - Google Patents

Description

The present invention relates to an ultrasonic probe, particularly an intrabody cavity insertion type ultrasonic probe.

Ultrasonic diagnostic equipment is used in the medical field. An ultrasonic diagnostic apparatus is generally composed of an apparatus main body and an ultrasonic probe. As the ultrasonic probe, a body surface contact type ultrasonic probe and an intrabody cavity insertion type ultrasonic probe are known. Examples of the latter include a transvaginal probe, a transrectal probe, a transesophageal probe, and the like. When acquiring volume data (three-dimensional data) in the body cavity, for example, a mechanical scanning type 3D probe is used.

The mechanical scanning type 3D probe has a tip portion accommodating an oscillator unit and a scanning mechanism, an intermediate portion extending from the tip portion, and an operating portion connected to the intermediate portion. The tip portion and the intermediate portion form an insertion portion, and the insertion portion is inserted into the body cavity. The tip is usually filled with an acoustic medium. In order to mechanically scan the oscillator unit in the acoustic medium, it is necessary to provide a drive source in the 3D probe that generates a corresponding driving force.

Patent Document 1-3 discloses an ultrasonic probe. In the ultrasonic probe, the motor is arranged in a grip having a relatively large space. The driving force generated by the motor is transmitted to the scanning mechanism in the tip portion via a driving force transmitting member such as a shaft inserted in the intermediate portion. Patent Documents 1-3 do not disclose a detailed structure inside the tip portion, particularly a detailed structure of the vibrator portion.

Japanese Unexamined Patent Publication No. 2-167150 Japanese Unexamined Patent Publication No. 2-55050 Japanese Unexamined Patent Publication No. 2005-168614

In a mechanical scanning type ultrasonic probe having a tip portion to be inserted into the body cavity of a subject, miniaturization of the tip portion is required in order to reduce the burden on the subject. Further, in order to reduce the size of the drive source, it is also required to reduce the resistance that the vibrator unit receives from the acoustic propagation medium during mechanical scanning.

An object of the present invention is to reduce the size or weight of the tip of a mechanical scanning ultrasonic probe having a tip to be inserted into a body cavity. Alternatively, the object is to reduce the resistance received from the acoustic propagation medium by the vibrator portion that is mechanically scanned in the tip portion.

The ultrasonic probe according to the embodiment includes a tip portion to be inserted into a body cavity, and the tip portions are provided in a tip portion case and a plurality of portions provided in the tip portion case and arranged in an arcuate electron scanning direction. A vibrator portion having a vibrating element of the above, and a scanning mechanism provided in the tip case and swinging the vibrator portion in an arcuate mechanical scanning direction orthogonal to the electron scanning direction. A recess is formed on the back surface side of the vibrator portion, the scanning mechanism has a shaft member for swinging the vibrator portion, and at least a part of the shaft member is inserted into the recess. And.

According to the above configuration, an ultrasonic beam is formed by the vibrator portion, and the ultrasonic beam is electronically scanned. The scanning mechanism mechanically scans the vibrator portion around the central axis of the shaft member. A recess is formed on the back surface side of the vibrator portion (the side opposite to the ultrasonic wave emitting side). When a plurality of vibrating elements are arranged in an arc shape, a reductionable portion is generated on the back surface side of the vibrator portion (between one end and the other end in the electron scanning direction of the vibrator portion). A recess is formed using that portion.

In the above configuration, at least a part of the shaft member is inserted in the recess. In the embodiment, the entire shaft member is embedded in the recess. By forming the recess, the physical quantity of the vibrator can be reduced. If at least a part of the shaft member is inserted in the recess, the rotating shaft approaches the vibrator portion, so that the amount of the member for connecting the two can be reduced. As a result, the tip can be made smaller or lighter. When the vibrator portion swings in the acoustic propagation medium, it is possible to reduce the load caused by the collision with the acoustic propagation medium. This makes it possible to reduce the size of the drive source. The shaft member may be configured as a rotating body, and the vibrator portion may rotate integrally with the rotating body. The shaft member may be configured as a non-rotating body, and the vibrator portion may rotate around the shaft member.

In an embodiment, the scanning mechanism has a holding member that holds the shaft member, and at least a part of the holding member is inserted into the recess. According to this configuration, the space inside the recess can be more utilized.

In an embodiment, the shaft member has a central shaft, and the holding member has a bifurcated portion having a first bearing and a second bearing separated in the direction of the central shaft, the first bearing and the said. The second bearing rotatably holds the shaft member. According to this configuration, since the shaft member is held at at least two places, the shaft member can be stably held. The first bearing and the second bearing may be connected to each other, but the shaft member can be held more stably when they are separated from each other.

In the embodiment, the mechanical scanning mechanism has a driving gear, and the vibrator portion has a driven gear which is a gear fixed to the shaft member and receives a driving force from the driving gear, and has the second bearing. The first bearing is provided on one side, and the driven gear is provided on the other side of the second bearing. According to this configuration, the driving force can be transmitted to the shaft member by utilizing the vacant space while holding the shaft member at at least two places.

In an embodiment, the recess has a rectangular back opening, the back opening having one edge corresponding to one end in the electron scanning direction and the other edge corresponding to the other end in the electron scanning direction. The total length of the shaft member is shorter than the opening length between the one edge and the other edge. According to this configuration, since the total length of the shaft member is shorter than the opening length of the back opening, the shaft member can be easily arranged in the recess.

In an embodiment, the recess has one side opening and the other side opening that are connected to the back opening. According to this configuration, it is possible to reduce the area that collides with the acoustic propagation medium during mechanical scanning of the vibrator unit.

According to the present invention, in a mechanical scanning type ultrasonic probe having a tip portion inserted into a body cavity, the tip portion can be miniaturized or lightened. Alternatively, the resistance received from the acoustic propagation medium by the vibrator portion mechanically scanned in the tip portion can be reduced.

It is a side view which shows the ultrasonic probe which concerns on embodiment. It is a perspective view which shows the tip part and the neck part. It is a perspective view which shows the motor arranged in the intermediate part. It is a perspective view which shows the structure in the tip part. It is sectional drawing which shows the yz cross section of the ultrasonic probe which concerns on embodiment. It is sectional drawing which shows the xz cross section of the ultrasonic probe which concerns on embodiment. It is sectional drawing which shows the vibrator part and a part of a scanning mechanism in an enlarged manner. It is a schematic diagram which shows a vibrator part and a shaft member. It is a side view which shows the cross-sectional position. It is sectional drawing corresponding to the sectional position shown in FIG. It is a figure which shows the sheet bundle for wiring.

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

FIG. 1 shows the ultrasonic probe 10 according to the embodiment. The ultrasonic probe 10 is an intra-body cavity insertion type and mechanical scanning type 3D probe. Examples of body cavities include vagina, rectum, esophagus and the like. In the configuration example shown in FIG. 1, the puncture adapter 12 is attached to the ultrasonic probe 10. The puncture adapter 12 is an instrument for holding or guiding the puncture needle 14. When puncturing is performed, the puncturing adapter 12 is attached to the ultrasonic probe 10, and when puncturing is not performed, the puncturing adapter 12 is removed from the ultrasonic probe 10.

The ultrasonic probe 10 has a main body 16, a cable 18, and a connector (not shown). The connector of the ultrasonic probe 10 is physically and electrically connected to the connector of the ultrasonic diagnostic apparatus main body (not shown). The main body 16 is roughly divided into an insertion unit 20 and an operation unit 22. The insertion portion 20 is a portion that can be inserted into the body cavity. The insertion portion 20 has a form extending in the z direction, which is the insertion direction. The operation unit 22 is a portion gripped by a user (doctor or the like). The operation unit 22 also has a form extending in the z direction. However, the central axis (center line) 36 of the operation unit 22 is shifted to the positive side in the y direction with respect to the central axis 32 of the axial portion 30, which will be described later. The front side of the operation unit 22 is a transition portion 44, and the central shaft 34 thereof is inclined while straddling between the central shaft 32 and the central shaft 36. As a result, the main body 16 has a crank shape.

A gap 42 is formed above the rod-shaped grip portion of the operation unit 22. With such a configuration, and because the tip portion 24 is hardly enlarged upward, the puncture needle 14 can be brought closer to the main body 16.

The insertion portion 20 is composed of a tip portion 24 and an intermediate portion 26 connected thereto. The tip portion 24 is a head portion, and a vibrator portion and a scanning mechanism are provided inside the tip portion 24. Specifically, a medium chamber is formed in the tip portion 24, and the vibrator portion is mechanically scanned in the medium chamber. The tip 24 has a central axis 38. The central axis 38 is shifted from the central axis 32 of the axial portion 30 to the positive side in the y direction. The shift amount is indicated by reference numeral 40. The tip portion 24 is enlarged in the shift direction.

The intermediate portion 26 has a rod-shaped or columnar shaft-shaped portion 30 and a neck portion 28 connected to the front side thereof. The neck portion 28 has a form in which it gradually enlarges from the axial portion 30 side to the tip portion 24 side. The tip portion 24 is larger than the shaft-shaped portion 30. The tip portion 24 and the neck portion 28 can be said to be an enlarged portion 41 when viewed from the shaft-shaped portion 30.

In the ultrasonic probe 10 according to the embodiment, as described below, a motor as a drive source is arranged inside the front side portion 26A of the intermediate portion 26. The driving force generated there is transmitted to the scanning mechanism, and the vibrator is mechanically scanned by the scanning mechanism. Further, in the ultrasonic probe 10 according to the embodiment, as described below, as the internal structure of the tip portion 24, a structure capable of reducing the size and weight is adopted.

FIG. 2 shows the inside of the tip portion 24 and the intermediate portion 26. In addition, in FIG. 1, the y direction was directed downward, but in FIG. 2, the y direction is directed upward.

The tip portion 24 has a case (tip portion case) 52, and an airtight medium chamber 58 is formed inside the case 52. The medium chamber 58 is filled with an acoustic propagation medium such as oil having an insulating property. Inside the medium chamber 58, the vibrator portion 62 is mechanically scanned by the scanning mechanism 60. Specifically, the vibrator portion 62 swings around the rotation axis (central axis) 64 of the shaft member described later. The rotation axis 64 is parallel to the y direction.

In FIG. 2, the arc-shaped electron scanning direction is shown as the θ direction, and the arc-shaped mechanical scanning direction is shown as the φ direction. The midpoint in each scanning direction is on the central axis of the tip 24 (see reference numeral 38 in FIG. 1). The vibrator unit 62 has a vibrating element array composed of, for example, a hundred and several tens of vibrating elements arranged in the θ direction. While repeating the electron scanning of the ultrasonic beam, the vibrator portion 62 is repeatedly mechanically scanned in one direction and the other direction. As a result, the three-dimensional echo data acquisition region is repeatedly formed. In the ultrasonic diagnostic apparatus main body (not shown), an ultrasonic image is formed based on the volume data acquired from the three-dimensional echo data acquisition region.

A structure 56 that functions as a skeleton or a base is provided in the tip portion 24. The structure 56 is made of metal. The scanning mechanism 60 is directly held by the structure 56, and the vibrator portion 62 is indirectly held by the structure 56. The structure 56, together with the case 52, also functions as a partition wall defining the medium chamber 58.

The intermediate portion 26 has a tubular case (intermediate portion case) 50 forming the outer skin of the shaft-shaped portion 30 and the neck portion 28. Both the case 50 and the case 52 are made of an insulating resin. At least the ultrasonic wave transmitting portion in the case 52 is made of a material having an acoustic impedance close to the acoustic impedance of a living body.

As described above, the motor 54 as a drive source is arranged inside the front portion of the intermediate portion 26. The tip portion of the motor 54 is held in a cantilever manner by a holding member (holder described later) in the neck portion 28. The motor 54 is arranged on the central axis of the shaft-shaped portion 30 (see reference numeral 32 in FIG. 1) and has an elongated shape extending along the central axis. Specifically, the motor 54 has a columnar shape. The motor 54 is, for example, a brushless motor. Other types of motors may be utilized. A drive source other than the motor may be used.

FIG. 3 is a perspective view of the intermediate portion, in which the motor 54 appears. As described above, the intermediate portion is composed of the shaft-shaped portion 30 and the neck portion 28. The case 50 is a hollow tubular member. A holder 66 having a tubular shape is arranged inside the neck portion 28. The holder 66 is composed of a first portion 66A and a second portion 66B, and in the illustrated configuration, the first portion 66A holds the tip portion 54A of the motor 54. The holding method is a cantilever method, and the rear end portion 54B of the motor 54 is in a non-holding state. By adopting the cantilever method, the number of parts can be reduced and the assembling property can be improved. Incidentally, the coupling 67 is rotatably arranged inside the second portion 66B. The coupling 67 is a member that connects the motor shaft and the shaft for transmitting the driving force.

The holder 66 is connected to a structure in the tip portion (see reference numeral 56 in FIG. 2). After all, the structure indirectly holds the motor 54. More specifically, a ring-shaped gap 55 is formed around the motor 54 between the motor 54 and a metal pipe described later. The wiring member passes through the gap 55. A sensor for detecting the rotation angle of the motor 54 is provided, but the sensor is not shown. Since there is more space inside the neck portion 28 than inside the shaft-shaped portion 30, a holder 66 for holding the tip portion of the motor 54 with respect to the internal space of the neck portion 28 is provided. However, the tip portion of the motor 54 may be directly held by the structure in the tip portion. An empty space (the space on the left side of the holder 66 in FIG. 3) generated adjacent to the holder 66 inside the neck portion 28 is used as a space for passing the wiring member.

FIG. 4 shows the structure inside the tip portion. The structure 56 is composed of a base portion 56A as a circular pedestal and a support portion 56B forming a frame. The base portion 56A and the support portion 56B may be integrated. The support portion 56B has a hollow structure, and an intermediate shaft member, a plurality of gears, and the like are housed inside the support portion 56B. As described above, the medium chamber 58 as an airtight chamber is formed in the tip portion, and the scanning mechanism 60 and the vibrator portion 62 as a movable body are arranged in the medium chamber 58.

The scanning mechanism 60 includes a bearing member 70, a shaft member 76, and a transmission mechanism 80. The shaft member 76 is a member for swinging the vibrator portion 62. The vibrator portion 62 rotates around the central axis (center line) of the shaft member 76. The transmission mechanism will be described later.

The bearing member 70 has a mounting end portion 71, an intermediate portion 72, a first bearing end portion (first bearing) 74A, and a second bearing end portion (second bearing) 74B. The mounting end portion 71 has an enlarged plate-like shape, and the mounting end portion 71 is fixed on the mounting surface of the support portion 56B. The intermediate portion 72 connected to the mounting end portion 71 extends along the shaft member 76. The first bearing end 74A is connected to the first position on the mounting end 71 side of the intermediate portion 72, and the second bearing end 74B is located at the second position away from the mounting end 71 of the intermediate 72. It is connected. Each of the bearing ends 74A and 74B has a ring shape and has a bearing. The first position is a position through which the central axis of the tip portion passes or a position in the vicinity thereof. On the rotation axis, the second position is set on one side of the first position, and the third position is set on the other side of the first position. A spur gear 90, which will be described later, is provided at the third position.

The middle portion 72 and the two bearing end portions 74A and 74B as a whole form a bifurcated shape. The shaft member 76 is rotatably held by the two bearing ends 74A and 74B at two positions on the rotation shaft that are separated from each other. As a result, the holding state of the shaft member 76 is stabilized. Bearings or bearing ends may be further provided at other positions. In the present embodiment, the shaft member 76 rotates together with the vibrator portion 62, but it is also conceivable to configure the shaft member 76 as a non-rotating shaft. In the embodiment, a short shaft member 76 is used, and not both end portions of the shaft member 76 but the central portion and one end portion thereof are held. As a result, it is possible to provide a member for transmitting the driving force to the other end of the shaft member 76.

The vibrator portion 62 has a curved body 78 that is curved in an arc shape or a semicircle shape. The curved body 78 is also a laminated body composed of a plurality of layers. The laminated structure of the curved body 78 covers almost the entire bending direction (electron scanning direction). In the embodiment, the curved body 78 is not provided with a structure for holding the shaft member 76 at both ends.

Specifically, the curved body 78 has a vibrating element array composed of a plurality of vibrating elements arranged in an arcuate electron scanning direction. In the curved body 78, one or a plurality of matching layers are provided on the front side (ultrasonic wave emitting side) of the vibrating element array, and an acoustic lens is provided on the front side of the one or a plurality of matching layers. The surface of the acoustic lens faces the inner surface of the tip case. In the curved body 78, a backing is provided on the rear side, that is, the back side (the side opposite to the ultrasonic wave emitting side) of the vibrating element array. The backing is composed of a material that absorbs or scatters unwanted ultrasonic waves.

The curved body 78 is attached to a movable base 81 that functions as a pedestal or a skeleton. The movable base 81 is made of a metal material such as aluminum. The movable base 81 includes a central portion and a pair of pinnate portions. The central part has a shape like the lower part of a ship. A pair of pinnate portions extend from both ends of the central portion while being curved. The movable base 81 has a cylindrical front surface that is joined to the rear surface (back surface) of the backing, and also has a flat mounting surface on which the movable frame 82 is mounted. Since the mounting surface is formed, the movable frame 82 can be easily mounted on the movable base 81, and can be firmly mounted.

The movable frame 82 is a connecting member for attaching the vibrator portion 62 to the shaft member 76. Specifically, the movable frame is made of, for example, a metal member such as aluminum. The movable frame 82 has a pair of fixing portions 86, 88 fixed to the rotating shaft while holding the rotating shaft. Further, the movable frame 82 has a spur gear 90 that forms a part of the transmission mechanism 80. The spur gear 90 is a driven gear. From the above-mentioned functions of the movable frame 82, it is natural to understand the movable frame 82 as a member belonging to the scanning mechanism 60.

A recess 75 is formed on the back surface side of the vibrator portion 62 as an internal space formed inside the movable base 81. The recess 75 has a rectangular parallelepiped shape when viewed roughly. The recess 75 has a back opening and two side openings. At least a part of the scanning mechanism 60 is inserted in the recess 75, and in the embodiment, the entire shaft member 76 in the scanning mechanism 60 is inserted. However, a configuration may be adopted in which only a part of the shaft member 76 enters the recess 75. In the embodiment, the first bearing end portion 74A, the second bearing end portion 74B, and the main portion of the movable frame 82 are also arranged in the recess 75. However, a part of them may protrude from the recess 75. By the way, even if the movable frame 82 is regarded as a part of the vibrator portion 62, a part of the scanning mechanism is still inserted in the recess as the recess opened on the back side.

It is possible to adopt a semi-cylindrical form (having no recess) as the vibrator portion 62, but in such a case, a substantially non-functional portion is generated on the rear side of the semi-cylindrical portion. In the present embodiment, the recess 75 is formed in the whole or a part of the portion.

According to the embodiment, since the recess 75 is formed in the vibrator portion 62, the weight of the vibrator portion 62 is reduced by that amount. Further, the resistance received from the acoustic propagation medium in the vibrator unit 62 is reduced. Further, according to the embodiment, since the shaft member 76 is provided inside the recess 75, the shaft member 76 is brought closer to the vibrator portion 62. As a result, the internal structure of the tip portion can be miniaturized. Further, since the amount of the member for connecting the shaft member 76 and the vibrator portion 62 can be reduced, the weight can be reduced by that amount, and at the same time, the resistance received by the movable body from the acoustic propagation medium can be reduced. .. As a result, the tip portion can be made smaller and lighter. Further, since the resistance generated by the vibrator unit 62 and the scanning mechanism 60 is reduced, the driving force required for mechanical scanning can be reduced, that is, the motor can be miniaturized. In other words, it is possible to arrange the motor inside the middle part without making it thicker.

The detailed structure of the tip portion 24, the neck portion 28, and the shaft-shaped portion 30 will be described with reference to FIGS. 5 and 6. FIG. 5 shows a yz cross section, and FIG. 6 shows an xz cross section.

In FIG. 5, the motor 54 is arranged (on the front side portion in the intermediate portion) across the neck portion 28 and the shaft-shaped portion 30. In the intermediate portion, a pipe 104 made of a hard material, specifically a metal, is arranged in a hollow case 50 made of an insulating material. The pipe 104 functions as an exoskeleton body, that is, exerts an action of increasing the strength of the insertion portion. At the same time, it exerts an electromagnetic wave shielding action. The outer surface of the pipe 104 is in close contact with the inner surface of the case 50. The pipe 104 is made of a metal such as stainless steel. The tip portion of the pipe 104 is connected to a holder 66 that holds the tip portion of the motor 54. A slit-shaped opening 104A is formed on the front end portion of the pipe 104 and on the side surface thereof. The wiring member 106 has entered the inside of the pipe 104 through the opening 104A. A ring-shaped gap 55 is formed between the pipe 104 and the motor 54, and the wiring member 106 passes through the gap 55. The wiring member 106 is configured as a laminated body (sheet bundle) composed of a plurality of sheets, and the wiring member 106 passes through the gap 55 in the state of the sheet bundle. However, a plurality of dispersed sheets may be passed through the gap 55. In FIG. 5, the wiring member that comes out of the vibrator portion 62 is not shown in the tip portion 24.

The shaft of the motor 54 is connected to the shaft 92 by a coupling 67. The motor 54 and the shaft 92 are arranged side by side on the central axis of the shaft-shaped portion 30. A bevel gear 94 is formed at the tip of the shaft 92. On the other hand, the bevel gear 96 is provided on the intermediate shaft member 100 that is rotatably provided. The bevel gear 94 and the bevel gear 96 are meshed with each other, and the drive rotation of the former causes the latter to drive and rotate. The intermediate shaft member 100 is rotatably held by a pair of bearings 102. The pair of bearings 102 and the bearing member 70 described above are held by the structure 56.

A spur gear 98 is fixed to the intermediate shaft member 100, and the spur gear 98 meshes with the spur gear 90 on the vibrator portion 62 side. When the spur gear 98 is driven and rotated, the spur gear 90 is driven and rotated. As a result, the vibrator portion 62 rotates around the rotation axis (central axis) of the shaft member 76. Specifically, when the motor 54 rotates in one direction, the vibrator portion 62 swings to one side in the machine scanning direction, and when the motor 54 rotates in the other direction, the vibrator portion 62 moves to the other side in the machine scanning direction. It swings in the direction.

The scanning mechanism 60 has a transmission mechanism 80, and in the embodiment, the transmission mechanism 80 includes a shaft 92, a bevel gear 94 as an end portion of the shaft 92, an intermediate shaft member 100, a spur gear 98, a spur gear 90, and the like. Have. The scanning mechanism 60 includes a bearing member 70, a shaft member 76, and the like in addition to the transmission mechanism 80. However, the concrete configuration shown is only an example. The intermediate shaft member may be excluded so that the rotational force of the shaft 92 is directly transmitted to the vibrator portion 62. The rotation speed may be adjusted by the action of a plurality of gears. Although a part of the shaft exists in the neck portion 28, since the main portion of the scanning mechanism 60 is arranged in the tip portion 24, the scanning mechanism 60 is a mechanism arranged in the tip portion 24. Can be said. However, the shaft 92 may be understood as an element other than the scanning mechanism 60.

In FIG. 5, one end in the electron scanning direction is represented as + θ1, and the other end in the electron scanning direction is represented as −θ1. The angle range in which the electron scanning is performed is, for example, a range from −90 ° to + 90 °. The midpoint (and origin) in the electron scanning direction is located on the central axis 38 of the tip portion 24. The case 52 is connected to the case 50. The hemispherical portion in the case 52 is the biological contact portion 52A.

In FIG. 6, the motor 54 and the shaft 92 are arranged on the central shaft 32 of the shaft-shaped portion. The intermediate shaft member 100 is rotatably held by a pair of bearings fixed to the support portion 56B. A spur gear 98 is fixed to the intermediate shaft member 100, and it meshes with the spur gear 90 on the vibrator portion 62 side. They form part of the transmission mechanism 80. In FIG. 6, one end in the machine scanning direction is represented by + φ1, and the other end in the machine scanning direction is represented by −φ1. The angle range in which the machine scan is performed is, for example, a range from −75 ° to + 75 °. The midpoint (and origin) in the machine scanning direction is located on the central axis 38 of the tip portion 24.

In FIG. 7, a part of the tip portion is shown as an enlarged cross-sectional view. The scanning mechanism 60 has a shaft member 76. The shaft member 76 is rotatably held by the first and second bearing end portions 74A and 74B. On the other hand, the vibrator portion 62 has a curved body 78 and a movable base 81. The curved portion indicated by reference numeral 108 corresponds to the vibrating element array or one or a plurality of matching layers. An acoustic lens 110 is provided on the front side of the portion 108, and a backing 107 is provided on the rear side, that is, the back side of the portion 108. The curved body 78 is fixed to the movable base 81. A recess 75 is formed inside the movable base 81. In the embodiment, the entire shaft member 76 is housed in the recess 75, and the main parts of the first and second bearing end portions 74A and 74B are housed. Further, a movable frame 82 forming a part of the scanning mechanism 60 is also housed.

With such a configuration, the tip portion is made smaller and lighter. Further, by reducing the load generated during the swinging motion of the vibrator portion 62, the size of the motor as a drive source is reduced. Each of the above advantages can be obtained by allowing at least a part of the shaft member to enter the recess 75.

In FIG. 8, a part of the tip portion is shown as a schematic view. (A) shows the yz plane, and (B) shows the xy plane. When the recess 75 is viewed as a wide groove, the y direction is the groove width direction, the x direction is the groove center line direction, and the z direction is the groove depth direction. In the recess 75, the y direction is the longitudinal direction and the x direction is the lateral direction. Reference numeral 64 indicates a central axis, that is, a rotation axis of the shaft member 76.

In the yz plane shown in (A), the movable base 81 is provided on the back surface side of the curved body 78. The inner space on the back side of the movable base 81 is the recess 75. The recess has a rectangular back opening 202 whose position in the z direction is indicated by reference numeral 112. The positions at both ends of the shaft member 76 in the z direction are indicated by reference numerals 204 and 206. The position of the bottom of the recess in the z direction is indicated by reference numeral 208. In the z direction, the positions 204 and 206 at both ends of the shaft member are both on the front side (positive side in the z direction) of the position 112 of the back opening 202. That is, in the yz plane, all of the shaft members 76 are housed in the recess 75.

In the xy plane shown in (B), the back opening 202 of the recess 75 is between the one end 78A and the other end 78B in the electron scanning direction of the curved body 78. The back opening 202 has one edge 202A in contact with one end 78A and the other edge 202B in contact with the other end 78B. The opening length 212 is between one edge 202A and the other edge 202B. The total length 210 of the shaft member in the y direction is shorter than the opening length 212. That is, even in the xy plane, the entire shaft member 76 is housed in the recess 75. Both ends of the shaft member 76 are in a non-contact state with the curved body 78. In other words, in the embodiment, a short shaft member 76 is used.

The recess 75 has a back opening 202 and a pair of side openings 75A, 75B. The pair of side openings 75A and 75B reduces the area of the vibrator portion that collides with the acoustic propagation medium. However, a configuration in which the pair of side openings 75A and 75B are closed may be adopted. For example, a streamlined bulge may be provided on the vibrator portion.

The thickness of the central portion of the movable base 81 may be made thinner, and the depth of the recess 75 may be made deeper. When the total length of the curved body 78 in the electron scanning direction is short, only a part of the shaft member 76 may be put in the recess 75. The shaft member may be arranged so as to connect one end 78A and the other end 78B of the curved body 78. In that case, the shaft member can be held between the one end 78A and the other end 78B. Due to the miniaturization of the tip inserted into the body cavity, it is difficult to install the bearing structure on the outside of the curved body. Therefore, it is desirable to adopt a configuration in which the shaft member is held not at both ends of the shaft member but at an intermediate portion excluding both ends thereof. As a modification, a mode in which a part of the configuration for holding the shaft member (for example, a plurality of bearings) enters the recess can be considered.

FIG. 9 shows the AA cross-sectional position of the neck portion 28. A cross-sectional view corresponding to that position is shown in FIG. In FIG. 10, a case 50 in the middle portion and a case 52 in the tip portion appear. A motor 54 is arranged in the pipe 104. An opening 104A is formed on the lower side (positive side in the y direction) of the pipe 104. A wiring member (not shown) is inserted into the pipe 104 from the space 113 in the neck portion through the opening 104A.

FIG. 11 illustrates a wiring member. The illustrated wiring member 116 is composed of a plurality of laminated wiring sheets 118, which constitute a sheet bundle. A plurality of wiring sheets 118 are pulled out from one side surface of the vibrator portion, and they are appropriately folded to form a sheet bundle. The sheet bundle passes through the structure (bulkhead) from the medium chamber, enters the internal space of the neck portion, and is pulled out to the operation portion through the internal space of the pipe.

In each sheet 118, at least the portion near the motor has a structure schematically shown on the right side of FIG. The sheet 118 includes a wiring sheet 120 and a ground tape 122. In the illustrated example, the wiring sheet 120 has a sheet body 134 made of an insulating material, and a ground layer 126 as a surface electrode and an insulating layer (coating layer) 128 are formed on one side thereof. On the other side of the sheet body 134, a signal line train 130 and an insulating layer 132 as wiring patterns are formed. The ground tape 122 has an adhesive layer 142, an insulating layer 138, a ground layer 135 as a surface electrode, and an insulating layer 140 from a side closer to the wiring sheet 120 to a side farther from the wiring sheet 120.

Since the signal line train 130 is sandwiched between the pair of ground layers 126 and 135, the entry of electromagnetic noise into the signal line train 130 is effectively suppressed. In particular, when the motor becomes a noise source, it is desirable to adopt the configuration shown in FIG. In the tip portion, it is desirable that each sheet is composed of the wiring sheet 120 alone. According to such a configuration, the load at the time of mechanical scanning of the vibrator can be reduced.

According to the above embodiment, since the concave portion is formed in the vibrator portion, the weight of the vibrator portion can be reduced, and the load generated by the vibrator portion colliding with the acoustic propagation medium can be reduced. Since the shaft member for the swing shaft member of the vibrator portion is arranged in the recess, the vibrator portion and the shaft member can be brought close to each other, and the scanning mechanism can be simplified and reduced in weight. In addition, the load generated by the scanning mechanism colliding with the acoustic propagation medium can be reduced. Therefore, the tip portion can be made smaller and lighter, and a small motor can be used as a drive source. As a result, the motor can be arranged inside the intermediate portion. The configuration provides the advantage of further weight reduction of the ultrasonic probe, and also provides a degree of freedom in the shape of the operating portion.

The above configuration can be applied to intrabody cavity insertion type probes such as a transvaginal probe, a transrectal probe, and a transesophageal probe. The internal structure of the tip can be applied to a body surface contact type probe as well as an intrabody cavity insertion type probe.

10 Ultrasonic probe, 16 body, 20 insertion part, 22 operation part, 24 tip part, 26 middle part, 28 neck part, 30 axial part, 41 enlarged part, 54 motor, 56 structure, 58 medium chamber, 60 scans Mechanism, 62 oscillator, 66 holder, 70 bearing member, 75 recess, 76 shaft member, 78 curved body, 80 transmission mechanism, 81 movable base.

Claims (3)

Including the tip that is inserted into the body cavity
The tip is
Tip case and
A vibrator portion provided in the tip case and having a plurality of vibrating elements arranged in an arcuate electron scanning direction, and a vibrator portion.
A mechanism provided in the tip case for swinging the vibrator in an arcuate mechanical scanning direction orthogonal to the electron scanning direction, and a shaft member for swinging the vibrator. And a scanning mechanism having a holding member for holding the shaft member, and
Including
Recess is formed on the back side of the front Symbol vibrator unit,
At least a portion of at least a portion and said retaining member of said shaft member is penetrated into the recess,
The shaft member has a central shaft and has a central shaft.
The holding member has a bifurcated portion having a first bearing and a second bearing separated in the direction of the central axis.
The first bearing and the second bearing rotatably hold the shaft member,
The scanning mechanism has a drive gear and
A driven gear, which is a gear fixed to the shaft member and receives a driving force from the driving gear, is provided.
The first bearing is provided on one side of the second bearing in the direction of the central axis.
The driven gear is provided on the other side of the second bearing in the direction of the central axis.
An ultrasonic probe characterized by that. In the ultrasonic probe according to claim 1,
The recess has a rectangular back opening
The back opening has one edge corresponding to one end in the electron scanning direction and the other edge corresponding to the other end in the electron scanning direction.
The total length of the shaft member is shorter than the opening length between the one edge and the other edge.
An ultrasonic probe characterized by that. In the ultrasonic probe according to claim 2,
The recess has one side opening and the other side opening that are connected to the back opening.
An ultrasonic probe characterized by that.