JP7398990B2 - ultrasonic probe - Google Patents

Description

The present disclosure relates to ultrasound probes.

Ultrasonic probes are used as ultrasound transmitters and receivers in medical ultrasound diagnostic equipment. Recently, an ultrasound probe has been loaded into a catheter, and ultrasound diagnosis has been carried out with the catheter inserted into the body.

Patent Document 1 discloses an active transducer element having a top main surface and a bottom main surface, a top electrode formed on the top main surface, a bottom electrode formed on the bottom main surface, and a direct electrical connection to the top electrode. An ultrasound probe is disclosed that includes a first lead connected to a bottom electrode and a second lead electrically connected to a bottom electrode through a conductive housing, a conductive bed, and a conductive backing element. .

Japanese Patent Application Publication No. 2006-198425

There is a strong demand for miniaturization of ultrasound probes loaded into catheters in order to reduce the burden on patients and to improve insertability into smaller diameter body cavities such as deep blood vessels.

The ultrasonic probe can be downsized by downsizing an ultrasonic transducer including a piezoelectric element including a piezoelectric body and a pair of electrodes. However, when the ultrasonic transducer is made smaller, the piezoelectric element also becomes smaller. Therefore, the electrodes of the piezoelectric element also become smaller, making it difficult to connect an electric signal line connecting the piezoelectric element and an external power source to the electrode of the piezoelectric element.

An object of the present disclosure is to provide an ultrasonic probe in which it is easy to connect an electric signal line to a piezoelectric element.

An ultrasonic probe as a first aspect of the present disclosure includes an ultrasonic transducer, a housing that supports the ultrasonic transducer, a first electric signal line, and a second electric signal line. The ultrasonic transducer includes: a flat piezoelectric body; a first electrode laminated on at least one side of the piezoelectric body in the thickness direction of the piezoelectric body; a second electrode laminated on at least the other side of the piezoelectric body in the thickness direction of the piezoelectric body, the housing being connected to the first electric signal line and connected to the first electrode; The device includes a first conductive member connected to the second electric signal line, and a second conductive member connected to the second electric signal line and the second electrode.

As one embodiment of the present disclosure, the first conductive member includes a first electrode terminal facing the first electrode, and the second conductive member includes a second electrode terminal facing the second electrode. Equipped with.

In one embodiment of the present disclosure, the first electrode includes a front electrode layer located on the one side in the thickness direction of the piezoelectric body, and a back electrode layer located on the other side in the thickness direction of the piezoelectric body. layer, and an interlayer conduction portion that conducts the front electrode layer and the back electrode layer.

As one embodiment of the present disclosure, the first electrode terminal is connected to the first electrode on the other side of the piezoelectric body in the thickness direction, and the second electrode terminal is connected to the first electrode on the other side of the piezoelectric body in the thickness direction. The other side in the thickness direction is connected to the second electrode.

In one embodiment of the present disclosure, the housing includes an insulating housing body that holds the first conductive member and the second conductive member.

In one embodiment of the present disclosure, the housing includes a first recess having a bottom surface formed by the first electrode terminal and an inner circumferential surface formed by the housing body, and a first recess formed by the second electrode terminal. a second recessed portion having a bottom surface formed therein and an inner circumferential surface formed by the housing body.

In one embodiment of the present disclosure, the first conductive member includes a first electric signal line terminal connected to the first electric signal line, and the second conductive member connects to the second electric signal line. A terminal for a second electric signal line to be connected is provided.

In one embodiment of the present disclosure, a first connector conductive member is connected to the first electrical signal line and contacts the first electrical signal line terminal, and a first connector conductive member is connected to the second electrical signal line and contacts the first electrical signal line terminal. The connector includes a second connector conductive member that contacts the second electrical signal line terminal.

One embodiment of the present disclosure includes a drive shaft that accommodates the first electrical signal line and the second electrical signal line, and the housing has an inner circumferential surface connected to an outer circumferential surface of the drive shaft. A connecting portion is provided.

In one embodiment of the present disclosure, the drive shaft and the shaft connection are made of metal.

According to the present disclosure, it is possible to provide an ultrasonic probe in which it is easy to connect an electric signal line to a piezoelectric element.

1 is a diagram illustrating a state in which an image diagnosis catheter including an ultrasound probe according to an embodiment of the present disclosure is connected to an external device; FIG. FIG. 2 is a cross-sectional view showing a cross section parallel to the longitudinal direction of the distal end portion of the diagnostic imaging catheter shown in FIG. 1. FIG. 3 is a sectional view showing a cross section parallel to the longitudinal direction of the ultrasound probe shown in FIG. 2. FIG. 3 is a perspective view showing the ultrasound probe shown in FIG. 2. FIG. 3 is a perspective view showing the housing of the ultrasound probe shown in FIG. 2. FIG. 6 is a perspective view showing the housing when viewed from a different direction from FIG. 5. FIG. 3 is a perspective view showing an ultrasound transducer of the ultrasound probe shown in FIG. 2. FIG. 8 is a perspective view showing a piezoelectric element of the ultrasonic transducer shown in FIG. 7. FIG. FIG. 3 is an exploded perspective view of the drive shaft assembly of the ultrasound probe shown in FIG. 2; FIG. 3 is a perspective view of the drive shaft assembly of the ultrasound probe shown in FIG. 2 in an assembled state. FIG. 1 is a cross-sectional view showing a portion of an imaging catheter including an ultrasound probe as an embodiment of the present disclosure.

Hereinafter, embodiments of an ultrasonic transducer according to the present disclosure will be described with reference to the drawings. Common members and parts in each figure are designated by the same reference numerals.

First, an example of an image diagnostic apparatus to which the ultrasound probe according to the present disclosure can be applied will be described. FIG. 1 is a diagram showing an image diagnostic apparatus 100 including an ultrasound probe 10 (see FIG. 2) as an embodiment.

The image diagnosis apparatus 100 includes an image diagnosis catheter 110 and an external device 120. FIG. 1 shows a state in which the diagnostic imaging catheter 110 is connected to an external device 120. FIG. 2 is a cross-sectional view showing a cross section parallel to the longitudinal direction A at the distal end of the diagnostic imaging catheter 110. FIG. 3 is a sectional view showing a cross section of the ultrasound probe 10 shown in FIG. 2 parallel to the longitudinal direction. FIG. 4 is a perspective view showing the ultrasound probe 10 shown in FIG. 2. In FIG. 4, the drive shaft 13 is shown in a simplified manner. FIG. 5 is a perspective view showing the housing 12 of the ultrasound probe 10 shown in FIG. 2. FIG. 6 is a perspective view showing the housing 12 when viewed from a different direction from FIG. FIG. 7 is a perspective view showing the ultrasound transducer 11 of the ultrasound probe 10 shown in FIG. FIG. 8 is a perspective view showing the piezoelectric element 1 of the ultrasonic transducer 11 shown in FIG. 7. FIG. 9 is an exploded perspective view of the drive shaft assembly 17 of the ultrasound probe 10 shown in FIG. 2. As shown in FIG. FIG. 10 is a perspective view of the drive shaft assembly 17 of the ultrasound probe 10 shown in FIG. 2 in an assembled state. In FIG. 10, the drive shaft 13 is shown in a simplified manner.

<Image diagnosis catheter 110>
The diagnostic imaging catheter 110 is applied to intravascular ultrasound (abbreviated as "IVUS"). As shown in FIG. 1, the diagnostic imaging catheter 110 is driven by being connected to an external device 120. More specifically, the diagnostic imaging catheter 110 of this embodiment is connected to a drive unit 120a of an external device 120.

Hereinafter, for convenience of explanation, in the imaging diagnostic catheter 110, the side of the imaging diagnostic catheter 110 that is inserted into the living body in the longitudinal direction A will be referred to as the "distal side", and the opposite side will be referred to as the "proximal end side". do. Further, the direction from the proximal end to the distal end of the diagnostic imaging catheter 110 may be simply referred to as "insertion direction A1." Further, the direction from the distal end to the proximal end of the diagnostic imaging catheter 110 may be simply referred to as "removal direction A2."

As shown in FIG. 1, the diagnostic imaging catheter 110 includes an insertion section 110a and an operation section 110b. The insertion portion 110a is a part of the diagnostic imaging catheter 110 that is inserted into a living body and used. The operating section 110b is a part of the diagnostic imaging catheter 110 that is operated outside the living body while the insertion section 110a is inserted into the living body. In the diagnostic imaging catheter 110 of this embodiment, a portion on the distal side of a distal end connector 42, which will be described later, is an insertion portion 110a, and a portion on the proximal side of the distal end connector 42 is an operating portion 110b.

As shown in FIGS. 1 and 2, the insertion section 110a includes an ultrasound probe 10 and a sheath 20.

As shown in FIG. 1, the operating section 110b includes an inner tube member 30 and an outer tube member 40. The inner tube member 30 holds the proximal end of the ultrasound probe 10 . The outer tube member 40 holds the proximal end of the sheath 20. Although details will be described later, the ultrasound probe 10 can move in the longitudinal direction A within the sheath 20 by moving the inner tube member 30 in the outer tube member 40 in the central axis direction. Further, although the details will be described later, the drive shaft assembly 17, which is a part of the ultrasound probe 10, passes through the inside of the inner tube member 30 and the outer tube member 40 in the longitudinal direction A only in the region of the insertion portion 110a. First, it extends over the area of the operation section 110b. That is, the operating section 110b of this embodiment is partially configured by the ultrasound probe 10 in addition to the inner tube member 30 and the outer tube member 40.

[Ultrasonic probe 10]
As shown in FIGS. 2 to 4, the ultrasound probe 10 includes an ultrasound transducer 11, a housing 12, and a drive shaft assembly 17. Drive shaft assembly 17 includes drive shaft 13 , first electrical signal line 14 , second electrical signal line 15 , and connector 16 .

As shown in FIGS. 7 and 8, the ultrasonic transducer 11 includes a piezoelectric element 1 and an acoustic matching member 2. Specifically, the piezoelectric element 1 includes a flat piezoelectric body 3, a first electrode 4 laminated on at least one side of the piezoelectric body 3 in the thickness direction B, and at least the other side of the piezoelectric body 3 in the thickness direction B. and a second electrode 5 laminated on the side. Hereinafter, for convenience of explanation, one side of the piezoelectric body 3 in the thickness direction B, on which at least a part of the first electrode 4 is provided, will be referred to as "the surface side of the piezoelectric element 1." Further, for convenience of explanation, the other side of the piezoelectric body 3 in the thickness direction B, on which at least a part of the second electrode 5 is provided, will be referred to as "the back side of the piezoelectric element 1." The front side of the piezoelectric element 1 is the side on which ultrasonic waves are transmitted and received. Further, the back side of the piezoelectric element 1 is the side opposite to the side where ultrasonic waves are transmitted and received.

The piezoelectric body 3 of the piezoelectric element 1 is made of, for example, a piezoelectric ceramic sheet. Examples of the material of the piezoelectric ceramic sheet include piezoelectric ceramic materials such as lead zirconate titanate (PZT) and lithium niobate. The piezoelectric body 3 may be made of quartz instead of a piezoelectric ceramic material.

The first electrode 4 and the second electrode 5 of the piezoelectric element 1 are laminated as electrode layers on both sides of the piezoelectric body 3 in the thickness direction B by, for example, an ion plating method using a mask material, a vapor deposition method, or a sputtering method. It can be formed by Examples of materials for the first electrode 4 and the second electrode 5 include metals such as silver, chromium, copper, nickel, and gold, and laminates of these metals.

The second electrode 5 of this embodiment is formed only on the back surface side of the piezoelectric element 1.

In contrast, the first electrode 4 of this embodiment is constituted by a folded electrode. Specifically, the first electrode 4 of this embodiment includes a front electrode layer 4a, a back electrode layer 4b, and an interlayer conductive portion 4c. The surface electrode layer 4a is located on the surface side of the piezoelectric element 1. The back electrode layer 4b is located on the back side of the piezoelectric element 1. The interlayer conductive portion 4c conducts the front electrode layer 4a and the back electrode layer 4b. In other words, the first electrode 4 of this embodiment is formed from the front side to the back side of the piezoelectric element 1. By making the first electrode 4 a folded electrode, the back electrode layer 4b of the first electrode 4 and the second electrode 5 can be placed together on the back side of the piezoelectric element 1. As a result, compared to the case where the first electrode 4 and the second electrode 5 are respectively arranged only on separate surfaces of the piezoelectric element 1, the first electric signal line 14 and the second electric signal line 15 and the first The connection work between the electrode 4 and the second electrode 5 can be performed only on one side of the piezoelectric element 1.

Although the piezoelectric element 1 includes a cutout portion 1c having an arcuate shape in the thickness direction B, and an interlayer conductive portion 4c is provided along the periphery of the cutout portion 1c, the structure is not limited to this. For example, the piezoelectric element 1 may not include the cutout portion 1c, and the interlayer conductive portion 4c may be provided along the outer peripheral surface of the piezoelectric element 1.

Furthermore, the piezoelectric element 1 includes a first portion 1a consisting of a portion where the first electrode 4 and the second electrode 5 overlap in the thickness direction B, and a second portion 1b excluding the first portion 1a.

The acoustic matching member 2 is laminated to cover a part of the surface side of the piezoelectric element 1. More specifically, the acoustic matching member 2 of this embodiment is laminated so as to cover only the entire surface side of the first portion 1a of the piezoelectric element 1; however, the structure is not limited to this, and for example, the acoustic matching member 2 of the piezoelectric element 1 may be laminated so as to cover the entire surface side of the piezoelectric element 1, or may be laminated so as to cover only a part of the surface side of the first portion 1a of the piezoelectric element 1.

By providing the acoustic matching member 2, the propagation efficiency of ultrasonic waves to the subject can be increased. In other words, the acoustic matching member 2 of this embodiment constitutes an acoustic matching layer that increases the propagation efficiency of ultrasonic waves.

The acoustic matching layer as the acoustic matching member 2 can be formed by pasting a sheet material forming the acoustic matching layer onto the piezoelectric element 1, by applying a liquid acoustic matching material forming the acoustic matching layer and curing it, etc. can be formed. Examples of the material for the acoustic matching member 2 include resin materials such as epoxy resin. Further, the acoustic matching member 2 may be formed of a laminate of resin layers made of a resin material.

As shown in FIGS. 3 and 4, the housing 12 supports the ultrasonic transducer 11. A proximal end of housing 12 is connected to drive shaft assembly 17 . The housing 12 has a hollow rod shape extending in the longitudinal direction A. An opening 12a having a rectangular shape when viewed in the thickness direction B is provided on the outer peripheral surface of the housing 12. The ultrasonic transducer 11 is housed in the opening 12a. The ultrasonic transducer 11 is arranged such that the second portion 1b of the piezoelectric element 1 is located in the extraction direction A2 more than the first portion 1a of the piezoelectric element 1. Further, the ultrasonic transducer 11 is arranged such that the surface side of the piezoelectric element 1 faces the outside of the opening 12a, that is, the outside of the housing 12 in the radial direction.

More specifically, the housing 12 of this embodiment includes a first conductive member 12b connected to the first electric signal line 14 and the first electrode 4 of the piezoelectric element 1, and a second electric signal line 15. A second conductive member 12c is connected to the second electrode 5 of the piezoelectric element 1. Examples of materials for the first conductive member 12b and the second conductive member 12c include metals such as copper, silver, gold, and nickel, and laminates of these metals. The housing 12 also includes an insulating housing main body 12d that holds the first conductive member 12b and the second conductive member 12c, and a metal shaft connecting portion 12e having an inner circumferential surface connected to the outer circumferential surface of the drive shaft 13. , is provided. The housing body 12d is made of, for example, insulating ceramics or resin. The housing 12 is formed using, for example, three-dimensional additive manufacturing (3D printer) technology. The outer diameter of the housing 12 is, for example, about 0.5 mm.

As shown in FIGS. 3 to 6, the first conductive member 12b includes a first electrode terminal 12f facing the first electrode 4. As shown in FIGS. The second conductive member 12c includes a second electrode terminal 12g facing the second electrode 5. The first electrode terminal 12f faces the back electrode layer 4b of the first electrode 4. Therefore, the first electrode terminal 12f is connected to the first electrode 4 on the back side of the piezoelectric element 1 (the other side in the thickness direction B), and the second electrode terminal 12g is connected to the back side of the piezoelectric element 1 (the other side in the thickness direction B). (the other side of B) is connected to the second electrode 5.

The housing 12 has a first recess 12h having a bottom surface formed by the first electrode terminal 12f and an inner peripheral surface formed by the housing body 12d, and a bottom surface formed by the second electrode terminal 12g and the housing body 12d. 2nd recessed part 12i which has an inner peripheral surface formed with. The first recess 12h and the second recess 12i are circular when viewed in the thickness direction B, but are not limited to this shape. Although the first recess 12h and the second recess 12i have the same shape, they are not limited to this. The first recess 12h and the second recess 12i are spaced apart from each other along the width direction C perpendicular to both the thickness direction B and the longitudinal direction A. Although the first recess 12h and the second recess 12i are arranged at the peripheral edge of the opening 12a, the present invention is not limited thereto. Shelf-like portions 12j projecting inward in the width direction C are provided on both edges of the opening 12a in the width direction C, respectively. Each shelf-shaped portion 12j has a large protruding amount inward in the width direction C at the base end side portion. A first recess 12h is provided at the proximal end of one shelf 12j, and a second recess 12i is provided at the proximal end of the other shelf 12j. The upper surfaces of both shelf-shaped portions 12j are formed flush with each other, and the ultrasonic transducer 11 is placed on the upper surface.

The conductive bonding material 18 is arranged in the first recess 12h and the second recess 12i. For example, a lump of solder, copper, or gold is placed in the first recess 12h and the second recess 12i as the conductive bonding material 18, and heated to connect the first electrode terminal 12f to the first electrode 4, and connect the first electrode terminal 12f to the first electrode 4. The second electrode terminal 12g can be connected to the second electrode 5. It is also possible to use a conductive adhesive as the conductive bonding material 18. The conductive bonding material 18 may be provided in advance on either or both of the first electrode 4 and the first electrode terminal 12f. The conductive bonding material 18 may be provided in advance on either or both of the second electrode 5 and the second electrode terminal 12g.

It is also possible to adopt a configuration in which the first recess 12h and the second recess 12i are not provided. In this case, for example, the first electrode 4 and the first electrode terminal 12f are brought into contact with each other, and while the first electrode 4 and the first electrode terminal 12f are kept in contact with each other, an adhesive such as an ultraviolet curable resin or the like is used. Alternatively, the ultrasonic transducer 11 may be fixed to the housing 12.

The housing main body 12d has a hollow rod shape extending in the longitudinal direction A. More specifically, the housing main body 12d includes a cylindrical peripheral wall 12k having an opening 12a, a partition wall 12l that separates the inside of the peripheral wall 12k into a distal end side and a proximal end side, and a rear surface of the ultrasonic transducer 11 from the partition wall 12l. A lattice portion 12m extending toward the distal end side along the lattice portion 12m is provided. A part of the first conductive member 12b and a part of the second conductive member 12c are embedded in the partition wall 12l.

The first conductive member 12b includes a first electrical signal line terminal 12n connected to the first electrical signal line 14. The second conductive member 12c includes a second electrical signal line terminal 12o connected to the second electrical signal line 15. The first electrical signal line terminal 12n and the second electrical signal line terminal 12o are exposed from the partition wall 12l to the base end side. The first electrical signal line terminal 12n and the second electrical signal line terminal 12o are configured as female connectors.

As shown in FIGS. 9 and 10, the connector 16 includes a first connector conductive member 16c connected to the first electrical signal line 14 and in contact with the first electrical signal line terminal 12n, and a second electrical signal line 15. and a second connector conductive member 16d that is connected to the second electrical signal line terminal 12o and contacts the second electrical signal line terminal 12o. The first connector conductive member 16c includes a first contact terminal 16e that contacts the first electrical signal line terminal 12n. The second connector conductive member 16d includes a second contact terminal 16f that contacts the second electrical signal line terminal 12o. The first connector conductive member 16c includes a first connection terminal 16g connected to the first electrical signal line 14. The second connector conductive member 16d includes a second connection terminal 16h connected to the second electrical signal line 15.

The first contact terminal 16e and the second contact terminal 16f are configured as male connectors. However, the configuration is not limited to this, and for example, the first contact terminal 16e and the second contact terminal 16f may be configured as female connectors, and the first electrical signal line terminal 12n and second electrical signal line terminal 12o may be configured as male connectors. It may also be configured as a type connector.

The connector 16 includes an insulative connector main body 16a that holds a first connector conductive member 16c and a second connector conductive member 16d, and an insulative connector lid portion 16b that fits into the connector main body 16a. The connector main body 16a and the connector lid portion 16b are made of, for example, insulating ceramics or resin. A portion of the first connector conductive member 16c and a portion of the second connector conductive member 16d are embedded in the connector body 16a. The first contact terminal 16e and the second contact terminal 16f are exposed from the connector main body 16a toward the tip side. The connector main body 16a and the connector lid portion 16b are formed using, for example, three-dimensional additive manufacturing (3D printer) technology.

By fitting the connector lid part 16b to the connector main body 16a, a disc-shaped part 16i and a truncated conical protrusion part 16j that projects from the disc-shaped part 16i toward the proximal end and whose diameter decreases toward the proximal end are formed. , is formed. The protruding portion 16j is fitted onto the inner circumferential surface of the distal end portion of the tubular drive shaft 13 by an interference fit.

The connector main body 16a is provided with a pair of grooves 16k extending from the protrusion 16j to the disk-shaped portion 16i. Each groove 16k opens at the proximal end surface of the protrusion 16j. The bottom surface at the tip of one groove 16k is formed by the first connection terminal 16g. The bottom surface at the tip of the other groove 16k is formed by a second connection terminal 16h. The tip of the first electric signal line 14 is arranged in one of the grooves 16k. The tip of the second electric signal line 15 is arranged in the other groove 16k. The tip of the first electric signal line 14 is fitted into one of the grooves 16k by interference fit. The tip of the second electric signal line 15 is fitted into the other groove 16k by tight fit. The tip of the first electrical signal line 14 includes a first connecting portion 14a made of a conductor exposed by removing the insulating covering material. The tip of the second electric signal line 15 includes a second connection portion 15a made of a conductor exposed by removing the insulating covering material.

The connector lid portion 16b includes a pair of protrusions 16l that fit into the pair of grooves 16k. One convex portion 16l is fitted into one groove 16k to press and connect the first connecting portion 14a to the first connecting terminal 16g. The other convex portion 16l presses and connects the second connecting portion 15a to the second connecting terminal 16h by fitting into the other groove 16k.

As shown in FIG. 3, the outer circumferential surface of the disc-shaped portion 16i is tightly fitted to the inner circumferential surface of the circumferential wall 12k of the housing main body 12d on the proximal end side of the partition wall 12l. A shaft connecting portion 12e is integrally provided at the base end of the peripheral wall 12k of the housing body 12d. The shaft connecting portion 12e is formed on the inner circumferential surface of the proximal end of the peripheral wall 12k and on the proximal end surface of the peripheral wall 12k. The housing 12 includes a positioning groove 12p extending in the longitudinal direction A on the shaft connecting portion 12e and the inner circumferential surface of the peripheral wall 12k on the proximal end side of the partition wall 12l. A positioning convex portion 16m is provided on the outer peripheral surface of the disk-shaped portion 16i of the connector 16. The positioning protrusion 16m fits into the positioning groove 12p. The first contact terminal 16e (see FIG. 9) of the connector 16 is tightly fitted into the first electrical signal line terminal 12n (see FIG. 4) of the first conductive member 12b. The second contact terminal 16f (see FIG. 9) of the connector 16 is tightly fitted into the second electrical signal line terminal 12o (see FIG. 4) of the second conductive member 12c.

In this way, the first electrical signal line 14 is connected to the first electrode 4 via the first connector conductive member 16c, the first conductive member 12b, and the conductive bonding material 18. Further, the second electrical signal line 15 is connected to the second electrode 5 via the second connector conductive member 16d, the second conductive member 12c, and the conductive bonding material 18. In this way, in this embodiment, the first electrical signal line 14 and the second electrical signal line 15 are connected to the piezoelectric element 1 via the first electrically conductive member 12b and the second electrically conductive member 12c provided in the housing 12. Therefore, the first electric signal line 14 and the second electric signal line 15 can be easily connected to the piezoelectric element 1. Further, in this embodiment, since the first recess 12h and the second recess 12i are provided, connection via the conductive bonding material 18 can be easily performed. Further, in this embodiment, since the connector 16 is provided, the first electrical signal line 14 and the second electrical signal line 15 can be easily connected to the first electrically conductive member 12b and the second electrically conductive member 12c.

The drive shaft 13 is made of a flexible tube. Inside the drive shaft 13, a first electric signal line 14 and a second electric signal line 15 connected to the ultrasonic transducer 11 are arranged. The drive shaft 13 is composed of two layers of metal coils wound in different directions around the axis. However, the configuration of the drive shaft 13 is not limited to this, and for example, the drive shaft 13 may be configured with three or more layers of coils. Examples of the material of the coil include stainless steel and Ni-Ti (nickel-titanium) alloy. By using such a drive shaft 13, even if the first electric signal line 14 and the second electric signal line 15 are configured with a double helical twisted pair cable, the shielding performance is improved and the first electric signal line 14 and the second electric signal line 15 are The influence of noise generated from the second electrical signal line 15 can be reduced.

The distal end of the metal drive shaft 13 is welded to the metal shaft connecting portion 12e, for example, via a metal bonding material. An example of the metal bonding material is solder. By welding the drive shaft 13 to the shaft connection portion 12e in this manner, the drive shaft assembly 17 can be firmly connected to the housing 12. However, the configuration is not limited to this, and for example, the fitting of the first contact terminal 16e and the second contact terminal 16f with the first electrical signal line terminal 12n and the second electrical signal line terminal 12o, and the disc-shaped portion The drive shaft assembly 17 may be configured to be securely connected to the housing 12 by a fit between the drive shaft assembly 16i and the peripheral wall 12k. In addition to these fits, the fit between the drive shaft 13 and the peripheral wall 12k may also be used to firmly connect the drive shaft assembly 17 to the housing 12.

The drive shaft 13 passes through the inner tube member 30 and the outer tube member 40 and extends to a hub 32, which will be described later, located at the proximal end of the inner tube member 30. That is, the drive shaft 13 extends in the longitudinal direction A from the distal end of the insertion section 110a to the proximal end of the operating section 110b.

As shown in FIG. 2, the first electric signal line 14 and the second electric signal line 15 extend inside the drive shaft 13 and electrically connect the ultrasonic transducer 11 and the external device 120. There is. That is, like the drive shaft 13, the first electrical signal line 14 and the second electrical signal line 15 extend in the longitudinal direction A from the distal end of the insertion section 110a to the proximal end of the operating section 110b. The first electrical signal line 14 and the second electrical signal line 15 may be flexible thin wire members having an outer diameter of more than 0 mm and less than or equal to 0.1 mm. The first electrical signal line 14 and the second electrical signal line 15 can be configured by, for example, a conducting wire with a diameter greater than 0 mm and less than or equal to 0.05 mm, and a covering material made of an insulating material and covering the periphery of the conducting wire.

As shown in FIGS. 3, 5, and 6, the lattice portion 12m includes a plurality of vertical lattices 12q that are perpendicular to the width direction C and extend in a direction along the back surface of the piezoelectric element 1, and a plurality of vertical lattices 12q that extend in the width direction C. and a horizontal lattice 12r that connects the tips of the plurality of vertical lattices 12q. Although the number of vertical grids 12q is 11 in this embodiment, it can be changed as appropriate. In FIGS. 5 and 6, only one vertical grid 12q is labeled. The base ends of the plurality of vertical lattices 12q are connected to the partition walls 12l. The plurality of vertical grids 12q are arranged at intervals in the width direction C. Each vertical lattice 12q has a tapered shape that gradually tapers toward the back surface of the piezoelectric element 1. A gap G is formed between the lattice portion 12m and the back surface of the piezoelectric element 1. The lattice portion 12m extends from the partition wall 12l to the tip end side of the piezoelectric element 1. The back surface of the lattice portion 12m is formed flush. In other words, the back surfaces of all the vertical grids 12q and the back surfaces of the horizontal grids 12r have shapes included in the same plane. The back shape and surface shape of the lattice portion 12m are not limited to these. The lattice portion 12m is not limited to a configuration having a plurality of vertical lattices 12q and horizontal lattices 12r. The range in which the lattice portions 12m are provided can be changed as appropriate. It is also possible to have a configuration in which the grid portion 12m is not provided.

A cavity H surrounded by the lattice part 12m and the peripheral wall 12k is formed on the back side of the lattice part 12m. A scattering portion 12t formed by a plurality of tapered convex portions 12s is provided in a portion of the peripheral wall 12k facing the cavity H. Although the number of tapered convex portions 12s is 11 in this embodiment, it can be changed as appropriate. In FIGS. 3 and 6, only one tapered convex portion 12s is labeled. Each tapered convex portion 12s extends in the longitudinal direction A. Each tapered convex portion 12s gradually tapers toward the radial inner side of the peripheral wall 12k. The scattering portion 12t extends from the partition wall 12l to the tip end side of the piezoelectric element 1. The shape of the scattering section 12t is not limited to this. The range in which the scattering portion 12t is provided can be changed as appropriate. It is also possible to have a configuration in which the scattering section 12t is not provided.

A tip opening 12u is provided at the tip of the housing body 12d. The tip opening 12u communicates with the cavity H and the gap G, respectively. The cavity H and the gap G are filled with an insulating adhesive 19. The adhesive 19 reaches the surface of the ultrasonic transducer 11, thereby firmly connecting the ultrasonic transducer 11 to the housing body 12d. For example, the adhesive 19 enters into the housing body 12d from the tip opening 12u, passes through the passage hole P provided between the upper part of the partition wall 12l and the base end of the ultrasonic transducer 11, and passes through the ultrasonic transducer 11. is introduced into the housing body 12d so as to reach the surface of the housing body 12d. It is preferable that the adhesive material 19 is filled into the cavity H and the gap G without any gaps. It is preferable that the adhesive 19 is made of a material having an ultrasonic attenuation function that attenuates the ultrasonic waves emitted from the back side of the piezoelectric element 1 . The adhesive 19 is made of, for example, an ultraviolet curable resin.

The grating portion 12m reflects and attenuates the ultrasonic waves emitted from the back side of the piezoelectric element 1, and allows the ultrasonic waves to enter the cavity H through between the plurality of vertical gratings 12q. The ultrasonic waves that have entered the cavity H are repeatedly reflected by the scattering section 12t and the back surface of the grating section 12m, and are attenuated within the cavity H. Therefore, it is possible to prevent the piezoelectric element 1 from receiving the ultrasonic waves emitted from the back side of the piezoelectric element 1 as a disturbance. The structure for attenuating ultrasonic waves on the back side of the piezoelectric element 1 is not limited to the structure using the grating section 12m, the scattering section 12t, and the adhesive 19 as described above. For example, instead of or in addition to such a structure, a backing material having an ultrasonic damping function may be provided on the back surface of the piezoelectric element 1. The backing material can be made of, for example, rubber or epoxy resin in which metal powder such as tungsten powder is dispersed.

[Sheath 20]
As shown in FIG. 2, the sheath 20 defines a first hollow section 21a and a second hollow section 21b. The ultrasonic probe 10 is accommodated in the first hollow part 21a. The ultrasound probe 10 can move forward and backward in the longitudinal direction A within the first hollow portion 21a. A guide wire W can be inserted into the second hollow portion 21b. In this embodiment, the tubular guide wire insertion part 20b that partitions the second hollow part 21b is parallel to the distal end of the tubular main body part 20a that partitions the first hollow part 21a. It is located in The main body portion 20a and the guide wire insertion portion 20b can be formed by joining different tube members by heat fusion or the like, but the formation method is not limited to this method.

As shown in FIG. 1, the main body portion 20a is provided with an X-ray contrast marker 22 made of a material that is opaque to X-rays. Furthermore, the guide wire insertion portion 20b is also provided with a marker 23 (see FIG. 2) having X-ray contrast properties. The markers 22 and 23 can be constructed of metal coils with high X-ray opacity, such as platinum, gold, iridium, tungsten, or the like.

As shown in FIG. 1, a window portion 24 is formed in the range in which the ultrasonic transducer 11 moves in the longitudinal direction A of the sheath 20, and the window portion 24 is formed to have higher ultrasound transmittance than other parts. . More specifically, the window portion 24 of this embodiment is formed in the main body portion 20a of the sheath 20.

The window portion 24 of the main body portion 20a and the guide wire insertion portion 20b are formed of a flexible material, and the material is not particularly limited. Examples of the constituent materials include various thermoplastic elastomers such as polyethylene, styrene, polyolefin, polyurethane, polyester, polyamide, polyimide, polybutadiene, transpolyisoprene, fluororubber, and chlorinated polyethylene. Alternatively, polymer alloys, polymer blends, laminates, etc. in which two or more types are combined can also be used.

The base end side of the main body portion 20a with respect to the window portion 24 has a reinforcing portion reinforced with a material having higher rigidity than the window portion 24. The reinforcing portion is formed by, for example, disposing a reinforcing material in which metal wires made of stainless steel or the like are braided into a mesh shape in a flexible tubular member such as resin. The tubular member is made of the same material as the window 24.

Preferably, a hydrophilic lubricating coating layer that exhibits lubricity when wet is disposed on the outer surface of the sheath 20.

As shown in FIG. 2, a communication hole 25 is formed at the distal end of the main body portion 20a of the sheath 20, which communicates the inside and outside of the first hollow portion 21a. During priming, the gas inside the main body portion 20a can be exhausted through the communication hole 25.

[Inner tube member 30 and outer tube member 40]
As shown in FIG. 1, the inner tube member 30 includes an inner tube 31 and a hub 32. The inner tube 31 is inserted into the outer tube member 40 so as to be movable forward and backward. The hub 32 is provided on the proximal end side of the inner tube 31.

As shown in FIG. 1, the outer tube member 40 includes an outer tube 41, a distal connector 42, and a proximal connector 43. The outer tube 41 is located outside the inner tube 31 in the radial direction, and the inner tube 31 moves forward and backward within the outer tube 41. The distal end connector 42 connects the proximal end of the main body 20a of the sheath 20 and the distal end of the outer tube 41. The proximal connector 43 is provided at the proximal end of the outer tube 41 and is configured to receive the inner tube 31 into the outer tube 41 .

The drive shaft 13, the first electric signal line 14, and the second electric signal line 15 of the ultrasound probe 10 described above are connected to the main body 20a of the sheath 20, and the outer tube member connected to the base end side of the main body 20a. 40 and extends to the hub 32 located at the proximal end of the inner tube member 30, which is partially inserted into the outer tube member 40.

The ultrasonic probe 10 and the inner tube member 30 described above are connected to each other so as to move forward and backward in the longitudinal direction A, respectively. Therefore, for example, when the inner tube member 30 is pushed in the insertion direction A1, the inner tube member 30 is pushed into the outer tube member 40 in the insertion direction A1. When the inner tube member 30 is pushed into the outer tube member 40 in the insertion direction A1, the ultrasound probe 10 connected to the inner tube member 30 moves within the main body 20a of the sheath 20 in the insertion direction A1. do. Conversely, when the inner tube member 30 is pulled in the removal direction A2, the inner tube member 30 is pulled out from the outer tube member 40 in the removal direction A2. When the inner tube member 30 is pulled out from within the outer tube member 40 in the withdrawal direction A2, the ultrasound probe 10 connected to the inner tube member 30 moves within the main body portion 20a of the sheath 20 in the withdrawal direction A2.

When the inner tube member 30 is pushed the most in the insertion direction A1, the distal end portion of the inner tube member 30 reaches near the distal end side connector 42 of the outer tube member 40. At this time, the ultrasonic transducer 11 of the ultrasonic probe 10 is located near the tip of the main body portion 20a of the sheath 20.

At the distal end of the inner tube member 30, there is a structure that prevents the inner tube member 30 from protruding further toward the distal end than the outer tube member 40, and also prevents the inner tube member 30 from protruding further toward the distal end than the outer tube member 40, and when the inner tube member 30 is pulled most proximally, the outer tube member 40 A stopper portion is provided on the proximal end side of the tube to prevent it from falling off. The stopper portion is not particularly limited as long as it has a configuration that can realize the above function, and may be configured by, for example, a wall portion that abuts the outer tube member 40 in the longitudinal direction A at a predetermined position.

A connector portion that is mechanically and electrically connected to the external device 120 is provided at the base end of the hub 32 of the inner tube member 30 . That is, the diagnostic imaging catheter 110 is mechanically and electrically connected to the external device 120 through the connector section provided on the hub 32 of the inner tube member 30. More specifically, the first electrical signal line 14 and the second electrical signal line 15 of the ultrasound probe 10 extend from the ultrasound transducer 11 to the connector section of the hub 32. The ultrasonic transducer 11 and the external device 120 are electrically connected in a state where the ultrasonic transducer 11 is connected to the external device 120. The received signal at the ultrasound transducer 11 is transmitted to the external device 120 via the connector section of the hub 32, subjected to predetermined processing, and displayed as an image.

<External device 120>
As shown in FIG. 1, the external device 120 includes a motor 121 that is a power source for rotating the drive shaft 13, and a motor 122 that is a power source for moving the drive shaft 13 in the longitudinal direction A. . The rotational motion of the motor 122 is converted into axial motion by a ball screw 123 connected to the motor 122.

More specifically, the external device 120 of this embodiment includes a drive unit 120a, a control device 120b electrically connected to the drive unit 120a by wire or wirelessly, and this control device 120b connected to the image diagnosis catheter 110. and a monitor 120c capable of displaying an image generated based on the received signal received from the monitor 120c. The above-described motor 121, motor 122, and ball screw 123 of this embodiment are provided in the drive unit 120a. The operation of this drive unit 120a is controlled by a control device 120b. The control device 120b can be configured by a processor including a CPU and memory.

The external device 120 is not limited to the configuration shown in this embodiment, and may have a configuration that further includes an external input unit such as a keyboard, for example.

The ultrasonic transducer according to the present disclosure is not limited to the specific configuration specified in the embodiments described above, and various modifications and changes can be made without departing from the gist of the invention described in the claims. . In the ultrasonic transducer 11 of this embodiment, the first electrode 4 is constituted by a folded electrode, but both the first electrode 4 and the second electrode 5 are not folded electrodes, but are laminated on only one side. It may be a configuration. Further, instead of the first electrode 4, the second electrode 5 may be configured by a folded electrode. However, as in this embodiment, by configuring the first electrode 4 as a folded electrode, the first electrode 4 and the second electrode 5 of the piezoelectric element 1 are connected to the first electrode of the housing 12 on the back side of the piezoelectric element 1. It is connected to the electrode terminal 12f and the second electrode terminal 12g. Therefore, the structure of the housing 12 can be simplified, thereby increasing the reliability of the electrical connection for the piezoelectric element 1.

Further, in the ultrasonic probe 10 of the embodiment described above, the first electrical signal line 14 and the second electrical signal line 15 are connected to the first electrically conductive member 12b and the second electrically conductive member 12c of the housing 12 via the connector 16. However, a configuration in which the connectors 16 are directly connected without using the connector 16 may be used. In this case, for example, the first connection part 14a of the first electric signal line 14 and the second connection part 15a of the second electric signal line 15 are coated with solder or other conductive material, thereby increasing the hardness. The first connecting portion 14a and the second connecting portion 15a are directly fitted into the first electric signal line terminal 12n of the first conductive member 12b and the second electric signal line terminal 12o of the second conductive member 12c. It is also possible to have a configuration in which the connection is made by

Further, although the ultrasound probe 10 of the embodiment described above has a configuration including only the ultrasound transducer 11 that enables intravascular ultrasound diagnosis as an imaging core, the configuration is not limited to this configuration. The configuration may further include an optical transmitter/receiver that enables optical coherence tomography (abbreviated as "OCT"). FIG. 11 is a cross-sectional view showing a part of an image diagnostic catheter 410 including an ultrasound transducer 11 and an ultrasound probe 310 including an optical transmitter/receiver 301. An ultrasound probe 310 shown in FIG. 11 differs from the ultrasound probe 10 described above in that a configuration that enables optical coherence tomography diagnosis is added.

Specifically, in the ultrasonic probe 310 shown in FIG. 11, in addition to the ultrasonic transducer 11, an optical transmitter/receiver 301 is disposed within the housing 12. The optical transmitter/receiver 301 continuously transmits light (measurement light) transmitted from an optical fiber cable as an optical signal line 302 extending inside the drive shaft 13 into the living body lumen, and also transmits light (measurement light) into the living body lumen. continuously receives reflected light from living tissue. The optical transmitter/receiver 301 transmits the received reflected light to the external device 120 (see FIG. 1) through the optical signal line 302. The control device 120b (see FIG. 1) of the external device 120 generates interference light data by causing the reflected light obtained by measurement to interfere with the reference light obtained by separating the light from the light source. Furthermore, the control device 120b of the external device 120 generates an optical tomographic image based on the generated interference light data, and displays it on the monitor 120c (see FIG. 1).

As shown in FIG. 11, within the drive shaft 13, the first electrical signal line 14 and the second electrical signal line 15 are spirally wound around the optical signal line 302. The two electric signal lines 15 extend parallel to each other. More specifically, the first electrical signal line 14 and the second electrical signal line 15 shown in FIG. 11 extend in a double spiral around an optical fiber cable serving as an optical signal line 302 extending in the longitudinal direction A. are doing.

The present disclosure relates to ultrasound probes.

1: Piezoelectric element 1a: First portion 1b: Second portion 1c: Notch portion 2: Acoustic matching member 3: Piezoelectric body 4: First electrode 4a: Front electrode layer 4b: Back electrode layer 4c: Interlayer conductive portion 5: Second electrode 10, 310: Ultrasonic probe 11: Ultrasonic transducer 12: Housing 12a: Opening 12b: First conductive member 12c: Second conductive member 12d: Housing body 12e: Shaft connecting portion 12f: First Electrode terminal 12g: Second electrode terminal 12h: First recess 12i: Second recess 12j: Shelf portion 12k: Peripheral wall 12l: Partition wall 12m: Grid portion 12n: First electric signal line terminal 12o: Second electric signal Line terminal 12p: Positioning groove 12q: Vertical lattice 12r: Horizontal lattice 12s: Tapered convex portion 12t: Scattering portion 12u: Tip opening 13: Drive shaft 14: First electrical signal line 14a: First connection portion 15: Second electrical Signal line 15a: Second connection part 16: Connector 16a: Connector main body 16b: Connector lid part 16c: First connector conductive member 16d: Second connector conductive member 16e: First contact terminal 16f: Second contact terminal 16g: First Connection terminal 16h: Second connection terminal 16i: Disk-shaped portion 16j: Protrusion 16k: Groove 16l: Convex portion 16m: Positioning convex portion 17: Drive shaft assembly 18: Conductive bonding material 19: Adhesive material 20: Sheath 20a: Main body Part 20b: Guide wire insertion part 21a: First hollow part 21b: Second hollow part 22, 23: Marker 24: Window part 25: Communication hole 30: Inner tube member 31: Inner tube 32: Hub 40: Outer tube member 41 : Outer tube 42 : Distal connector 43 : Proximal connector 100 : Imaging diagnostic apparatus 110, 410 : Imaging diagnostic catheter 110 a : Insertion part 110 b : Operating part 120 : External device 120 a : Drive unit 120 b : Control device 120 c : Monitor 121: Motor 122: Motor 123: Ball screw 301: Optical transmitter/receiver 302: Optical signal line A: Longitudinal direction of the catheter for diagnostic imaging A1: Insertion direction A2: Removal direction B: Thickness direction of piezoelectric element C: Width direction G: Gap H: Cavity W: Guide wire

Claims (7)

An ultrasonic probe comprising an ultrasonic transducer, a housing that supports the ultrasonic transducer, a first electrical signal line, and a second electrical signal line,
The ultrasonic transducer includes:
A flat piezoelectric body,
a first electrode laminated on at least one side of the piezoelectric body in the thickness direction of the piezoelectric body;
a second electrode laminated on at least the other side of the piezoelectric body in the thickness direction of the piezoelectric body;
The housing includes:
a first conductive member connected to the first electrical signal line and connected to the first electrode;
a second conductive member connected to the second electrical signal line and the second electrode ;
The first conductive member includes a first electrode terminal facing the first electrode,
The second conductive member includes a second electrode terminal facing the second electrode,
The housing includes:
an insulating housing body that holds the first conductive member and the second conductive member;
a first recess having a bottom surface formed by the first electrode terminal and an inner peripheral surface formed by the housing body;
An ultrasonic probe comprising: a second recess having a bottom surface formed by the second electrode terminal and an inner peripheral surface formed by the housing main body . The first electrode is
a surface electrode layer located on the one side of the piezoelectric body in the thickness direction;
a back electrode layer located on the other side of the piezoelectric body in the thickness direction;
The ultrasonic probe according to claim 1 , further comprising an interlayer conduction section that conducts the front electrode layer and the back electrode layer. The first electrode terminal is connected to the first electrode on the other side of the piezoelectric body in the thickness direction,
The ultrasonic probe according to claim 1 or 2 , wherein the second electrode terminal is connected to the second electrode on the other side of the piezoelectric body in the thickness direction. The first electrically conductive member includes a first electrical signal line terminal connected to the first electrical signal line,
The ultrasound probe according to any one of claims 1 to 3 , wherein the second electrically conductive member includes a second electrical signal line terminal connected to the second electrical signal line. a first connector conductive member connected to the first electrical signal line and in contact with the first electrical signal line terminal;
The ultrasonic probe according to claim 4 , further comprising a connector having a second connector conductive member connected to the second electric signal line and in contact with the second electric signal line terminal. comprising a drive shaft that accommodates the first electrical signal line and the second electrical signal line,
The ultrasonic probe according to any one of claims 1 to 5 , wherein the housing includes a shaft connecting portion having an inner peripheral surface connected to an outer peripheral surface of the drive shaft. The ultrasonic probe according to claim 6 , wherein the drive shaft and the shaft connection portion are made of metal.

Images