JPH11235343A - Ultrasonic probe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire an ultrasonogram of a deep site at high sensitivity and enhance transmission and reception performance by providing a rotor with a mounting part to which a connecting member is connected, connecting an ultrasonic transducer to the connecting member, and placing the ultrasonic transducer in a wide space inside a housing. SOLUTION: A rotor 20 connected to the flexible shaft 14 of a flexible cord 1b is provided with a circular part 20b, and a mounting part 22 having an axially extended flat surface is provided in a position away from the rotation axis of the circular part 20b. A connecting member 19 is connected to the mounting part 22. The back of backing 18 constituting an ultrasonic transducer 12 is secured to the connecting member 19, and the backing 18 is rotated integrally with the connecting member 19 to effect radial ultrasonic scans.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe which is inserted into a body cavity or the like and performs ultrasonic scanning in a rotational direction.

[0002]

2. Description of the Related Art As an ultrasonic probe for examining a tissue state in a body, a probe inserted into a body cavity has been widely used. This type of ultrasonic probe is composed of an ultrasonic scanning unit having a shaft connected thereto, and the shaft is formed of a flexible cord having flexibility. The ultrasonic probe may be inserted directly into the body cavity, or may be inserted into the body cavity via a guide means such as an endoscope. Since the endoscope is provided with a treatment instrument insertion channel for inserting a treatment instrument such as forceps, the treatment instrument insertion channel is generally used as an insertion path of the ultrasonic probe into the body cavity.

In a so-called ultrasonic probe for inserting an endoscope, which is inserted using a treatment tool insertion channel of an endoscope as a guide, an ultrasonic scanning unit has an ultrasonic transducer having a single-plate ultrasonic transducer. The diameter is reduced by providing a transducer. Scanning is performed over a predetermined range by the ultrasonic transducer, and there is a type that performs radial scanning by driving the ultrasonic transducer in a rotational direction. In the case of performing the radial scanning, means for driving the ultrasonic transducer to rotate is required. When the rotation driving means is provided at the distal end of the insertion portion, the diameter becomes large, so that the ultrasonic transducer is rotationally driven by remote control. For this purpose, the flexible cord forming the shaft connected to the ultrasonic scanning unit is formed by inserting a flexible shaft made of a close contact coil or the like into a flexible tube, Connect the connector part to the base end of. The connector section includes a fixed section connected to the tube and a rotating shaft connected to the flexible shaft, and is detachably connected to the scanning drive unit. The scanning drive unit is provided with a means for rotationally driving the rotating shaft of the connector portion, and thereby, by rotating the flexible shaft around the axis in the tube, the rotational force is transmitted to the ultrasonic transducer.

The ultrasonic probe having the above configuration is incorporated in a treatment tool insertion channel of an endoscope, and a connector provided on a proximal end thereof is connected to an ultrasonic operation section, and an insertion section of the endoscope is provided. Is inserted into the body cavity, and the ultrasonic scanning unit is arranged at a position in the body cavity where an ultrasonic inspection is to be performed. When ultrasonic pulses are transmitted into the body at predetermined angles during rotation of the ultrasonic transducer, a reflected echo is obtained from a tomographic portion of the body tissue, and the reflected echo is converted into an electric signal by the ultrasonic transducer. , And this signal is taken out. Then, an ultrasonic image is obtained by taking the reflected echo signal into an ultrasonic observation device and performing a predetermined process.

In an ultrasonic probe for performing radial ultrasonic scanning, a tip cap as a housing for accommodating an ultrasonic transducer in an ultrasonic scanning section is formed in a cylindrical shape, and the tip cap is made of a resin material or the like having excellent acoustic characteristics. And, at least the tip cap is filled with an ultrasonic transmission medium. Here, if the transmitting / receiving surface of the ultrasonic transducer constituting the ultrasonic transducer is widened, the focus point of the ultrasonic wave can be set farther, so that information of a deeper part can be obtained and the transmission / reception sensitivity can be improved.
When the thickness of the ultrasonic transducer is increased, the thickness of the backing material can be increased, so that the transmission and reception performance can be improved.

Here, in order to widen the transmitting / receiving surface or increase the thickness of the ultrasonic vibrator, it is necessary to widen the inside of the tip cap provided with the ultrasonic transducer. Even with an ultrasonic probe inserted through the treatment instrument insertion channel, the outer diameter of the ultrasonic scanning unit can be made larger than the inner diameter of the treatment instrument insertion channel. In this case, the flexible cord and the connector are made thinner than the inner diameter of the treatment instrument insertion channel, and the connector is inserted into the endoscope from the distal end side of the treatment instrument insertion channel. Therefore, the ultrasonic probe is incorporated in the treatment instrument insertion channel in advance before the insertion section of the endoscope is inserted into the body cavity.

[0007]

By the way, the connection between the ultrasonic transducer and the flexible shaft is
A rotating member is connected to and provided at the tip of the flexible shaft, and the rotating member is directly extended into a tip cap constituting the ultrasonic scanning unit, and the ultrasonic transducer is supported by the rotating member. Then, a flat surface is formed in a portion of the rotating member located in the tip cap, and the flat surface is used as a mounting portion of the ultrasonic transducer. Therefore, inside the tip cap, in a cross section orthogonal to the axis of the tip cap, the rotating member is located at the center thereof, and the portion where the ultrasonic transducer is mounted is a semicircle in the cross section of the tip cap. It will be a much smaller space. As a result, even if the diameter of the tip cap is increased, it is not always possible to effectively utilize the space, and there is a limit to increasing the surface area of the ultrasonic vibrator or increasing the thickness of the backing material. was there.

The present invention has been made in view of the above points, and an object of the present invention is to provide a large-sized ultrasonic transducer by effectively utilizing a space in a housing constituting an ultrasonic scanning unit. And the thickness of the backing material can be increased.

[0009]

In order to achieve the above-mentioned object, the present invention provides a cylindrical housing at the tip,
An ultrasonic transducer having an ultrasonic vibrator is mounted in the housing, the ultrasonic transducer is connected to a rotating body, and an ultrasonic wave is configured to perform ultrasonic scanning by driving the rotating body to rotate. In the probe, the rotating body is provided with a mounting portion at a position deviated from the rotation center axis to the housing inner surface side,
A connecting member is provided extending from the mounting portion in a direction parallel to the rotation center axis, and the ultrasonic transducer is connected to the connecting member.

Here, when the ultrasonic transducer is connected to the connecting member and its transmitting / receiving surface is disposed so as to face a plane substantially including the rotation center axis, the surface area of the ultrasonic transducer can be increased. If the transmitting / receiving surface is extended from the connection position of the connection member to a position beyond the rotation center axis, the thickness of the ultrasonic transducer can be increased. Further, a cable may be connected to the connecting member, and the connecting member may be electrically connected to the ultrasonic transducer via the connecting member. In this case, the connecting member also serves as a relay board.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. Here, in the embodiment described below, a description will be given of a configuration in which a treatment tool insertion channel of an endoscope is configured as an ultrasonic probe that is inserted into a body cavity as a guide means. The present invention can also be applied to the ultrasonic probe. Further, although the ultrasonic scanning section has a larger diameter than the flexible cord connected to the ultrasonic scanning section, the present invention can also be applied to an ultrasonic scanning section having the same outer diameter as the flexible cord.

First, FIG. 1 shows an overall configuration of an ultrasonic inspection apparatus. This ultrasonic inspection apparatus includes an ultrasonic probe 1, a scanning drive unit 2, an ultrasonic observation device 3, and a monitor 4 thereof.
It is composed of The ultrasonic probe 1 is inserted into a body cavity via the endoscope 5, and specifically, is provided in the main body operation section 5a of the endoscope 5, and is used for inserting forceps and other treatment tools. It is inserted from the treatment instrument introduction section 6 and is guided into the body cavity through the treatment instrument insertion channel 7 formed to penetrate the insertion section 5b from the main body operation section 5a. Here, the scanning drive unit 2 is attached to a movable arm 9 extending from a rack 8 on which the ultrasonic observation device 3 and the monitor 4 are mounted, and the cord 2a is detachably attached to the ultrasonic observation device 3. It is connected. The movable arm 9 bends in an arbitrary direction with a light load.

The ultrasonic probe 1 comprises an ultrasonic scanning section 1a, a flexible cord 1b, and a connector section 1c from the tip side. The outer diameter of the ultrasonic scanning section 1a is the largest, and the flexible cord 1b and the connector section 1c are thinner. The outer diameter of the flexible cord 1b and the connector 1c is smaller than the inner diameter of the treatment instrument insertion channel 7. 2 and 3, the ultrasonic scanning section 1a has a distal end cap 10 as a housing, and the distal end cap 10 is made of a material having a good ultrasonic transmission property, for example, a silicone resin. , Made of polyethylene or other synthetic resin, and made of a thin material. A flexible cord 1b is connected to the ultrasonic scanning unit 1a. To improve the shape retention of the tip cap 10 and to improve the connection strength with the flexible cord 1b, the tip cap 10 Is connected to a metal cap holding member 11. Here, the cap holding member 11
Has one end connected to the large-diameter tip cap 10 and the other end connected to the small-diameter flexible cord 1b.
It is composed of a large-diameter cap-side connecting portion 11a and a small-diameter cord-side connecting portion 11b.

An ultrasonic transducer 12 is provided in the distal end cap 10, and the ultrasonic transducer 12 is driven to rotate by remote control.
The flexible cord 1b is for transmitting rotation to the ultrasonic transducer 12, and the flexible cord 1b is a flexible tube 13 in which a flexible shaft 14 composed of a close-contact coil is inserted. And the cable 15 connected to the ultrasonic transducer 12
It is inserted into the flexible shaft 14. Therefore, the proximal end of the flexible shaft 14 is
Rotation about the axis within 3 will extend to the tip. Further, the cable 15 rotates together with the flexible shaft 14 and the ultrasonic transducer 12.

As shown in FIGS. 4 and 5, the ultrasonic transducer 12 has an ultrasonic vibrator 16 made of, for example, a ceramic piezoelectric element. A matching layer 17 is laminated,
A backing material 18 is provided on the back surface side, and has a substantially columnar shape as a whole. A concave portion 18a is formed on the opposite side of the transmitting / receiving surface of the ultrasonic transducer 12, that is, on the back surface of the backing material 18, and a connecting member 19 is fixed to the concave portion 18a by bonding or the like. In addition, chamfered portions 18b, 18b which are notched obliquely are formed at portions on the left and right sides of the backing material 18 where the connecting member 19 is fixed.
On the other hand, a rotating body 20 is connected to the tip of the flexible shaft 14 on the rotation transmitting side. The rotating body 20 has a cylindrical portion 20a and a circular portion 20b, and the distal end of the flexible shaft 14 is inserted into the cylindrical portion 20a and fixed by means such as spot welding. This cylindrical portion 20
a is located inside the cord-side connecting portion 11b of the cap holding member 11 for connecting the distal end cap 11 to the tube 13.

The cylindrical portion 20a of the rotating body 20 has a thicker portion at the transition from the cord-side connecting portion 11b to the cap-side connecting portion 11a of the cap holding member 11, and has a thicker portion between the cap holding member 11 and the cap. It is rotatably supported by interposing a bearing 21. Also, the cylindrical portion 20a
Is extended in the space of the ultrasonic scanning unit 1a. Here, the portion where the circular portion 20b is located is the cap-side connecting portion 11a of the cap holding member 11.
Inside.

The mounting portion 22 having a flat surface extending in the axial direction is provided at the outer peripheral portion of the circular portion 20b of the rotating body 20, that is, at a position away from the rotation center axis of the rotating body 20.
Are connected to each other, and the connecting member 19 is connected to the mounting portion 22. The connection between the connecting member 19 and the mounting portion 22 is performed using a connecting pin 23. For this reason, the mounting portion 22
Is provided with a pin insertion hole 22a, and a pin insertion hole 19a is also formed at a position corresponding to the pin insertion hole 22a of the mounting portion 22 of the connecting member 19. Therefore,
The connecting member 19 is incorporated in a state where the pin insertion hole 19a is aligned with the pin insertion hole 22a in the mounting portion 22,
The connecting pin 23 is inserted through the pin insertion holes 22a and 19a, and is fixed by means such as bonding or caulking.

As schematically shown in FIG. 5, the ultrasonic transducer 16 constituting the ultrasonic transducer 12 is provided with electrodes on both front and back surfaces thereof, and a cable 15 is connected to the electrodes. The cable 15 is connected to the connector 1
From c, it passes through the inside of the flexible shaft 14 composed of the close contact coil constituting the flexible cord 1b, passes through the inside of the rotating body 20, and is connected to the connecting member 19. Wiring from electrodes provided on both front and back surfaces of the ultrasonic vibrator 16 is connected to the connecting member 19, and a coil 24 is mounted as an electronic component, for example. Therefore, the connecting member 1
A predetermined wiring pattern and the like are formed on the surface of 9.
The connecting member 19 also functions as a relay board that connects the ultrasonic vibrator 16 and the cable 15. The connecting portion of the wiring from the ultrasonic transducer 16 and the connecting portion of the cable 15 in the connecting member 19 are connected to the ultrasonic transducer 12.
Is a portion between the joint portion with the ultrasonic transducer 12 and the joint portion with the mounting portion 22.

In the drawing, reference numeral 25 denotes an ultrasonic transmission medium supply passage for supplying an ultrasonic transmission medium to the inside of the distal end cap 10, and the ultrasonic transmission medium supply passage 25 is provided with a plug member. 26 allows it to be closed. Reference numeral 27 denotes a thread spool for fixing the tube 13 of the flexible cord 1b to a state in which the tube 13 is fitted to the cord-side connecting portion 11b of the cap holding member 11.

As described above, the ultrasonic transducer 12 including the ultrasonic vibrator 16 has the connecting member 1 on its back surface.
The connecting member 19 is connected to a mounting portion 22 provided on the outer peripheral portion of the rotating body 20.
Therefore, the connecting member 19 can be disposed at a position close to the inner surface of the tip cap 10 on condition that it does not interfere with the inner surface. As a result, in a cross section orthogonal to the axis of the tip cap 10, a wide space including the rotation center axis A is secured, and the ultrasonic transducer 12 can be mounted in this wide space. Moreover, the width of the connecting member 19 is reduced, and the ultrasonic transducer 1
2 is mounted in a concave portion 18a formed in the backing material 18, and the back surface of the backing material 18 and the surface of the connecting member 19 are at substantially the same height. Further, both sides of the connecting portion of the backing material 18 with the connecting member 19 are chamfered portions 18b. Therefore, even if the connecting member 19 is disposed at a position very close to the inner surface of the tip cap 10,
To perform ultrasonic scanning, the ultrasonic transducer 12
During rotation, the connecting member 19 and the like
It does not touch the inner surface of the zero. As a result, when the flexible shaft 14 is driven to rotate, the rotation is
0 to the connecting member 19, the ultrasonic transducer 12 rotates smoothly and radial scanning is performed, and there is no possibility that the connecting member 19 and the like slide on the inner surface of the distal end cap 10 during that time.

Here, the transmitting / receiving surface of the ultrasonic transducer 12 is arranged in parallel with the plate surface of the connecting member 19. Therefore, as described above, by disposing the connecting member 19 at a position close to the inner surface of the tip cap 10, as shown in FIG. 6, this transmitting / receiving surface substantially faces the surface including the center position of the tip cap 10. As a result, the surface area of the ultrasonic transducer 16 constituting the ultrasonic transducer 12 can be increased. As a result, the focus point of the transmitted ultrasonic wave can be set farther, an ultrasonic tomographic image of a deep part in the body can be obtained, and the transmission / reception sensitivity is improved.

On the other hand, as shown in FIG. 7, the transmitting / receiving surface of the ultrasonic transducer 12 may be extended to a position beyond the center position of the tip cap 10. As a result, the thickness of the ultrasonic transducer 12 as a whole increases, and therefore, the thickness of the ultrasonic transducer 16 can be increased. As a result, the thickness of the backing material 18 can be increased, and transmission / reception performance is improved.

The cable 15 connected to the ultrasonic vibrator 16 is generally a coaxial cable in the flexible shaft 14, but the resonance characteristics are eliminated by eliminating the influence of the distributed capacity of the coaxial cable. In order to stabilize the coil, the coil 2 is placed between the ultrasonic vibrator 16 and the cable 15.
For example, it is necessary to install an electronic component or the like at a position near the ultrasonic vibrator 16, for example, by providing the ultrasonic transducer 4. By providing the coil 24 in this manner, the transmission and reception impedance of the ultrasonic wave is increased,
There are advantages such as improved transmission / reception efficiency and improved S / N ratio. Since the connecting member 19 has a function as a relay board, these electronic components can be easily mounted on the connecting member 19. Further, when performing repair or the like, it may be necessary to separate the ultrasonic vibrator 16 and the cable 15. However, if the connection wiring of the cable 15 to the connecting member 19 is cut, separation can be easily performed. . When the repair or the like is completed, reconnection can be easily performed by soldering or the like.

[0024]

As described above, according to the present invention, the mounting portion is provided at a position deviated to the inner surface side of the housing, and the connecting member is provided extending from the mounting portion in a direction parallel to the rotation center axis. Since the ultrasonic transducer is connected to this connecting member, the ultrasonic transducer can be disposed in a large space inside the housing. It is possible to obtain an image or to increase the thickness of the backing material to improve transmission / reception performance.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an ultrasonic inspection apparatus according to an embodiment of the present invention, together with an endoscope provided to guide the ultrasonic probe.

FIG. 2 is a sectional view of a distal end portion of the ultrasonic probe.

FIG. 3 is a sectional view taken along line XX of FIG. 2;

FIG. 4 is an exploded perspective view showing a mounting structure of the ultrasonic transducer.

FIG. 5 is an external view of a state where the ultrasonic transducer is mounted on a mounting portion.

FIG. 6 is a sectional view taken along line YY of FIG. 2;

FIG. 7 is a sectional view similar to FIG. 6, showing a state where an ultrasonic transducer having another structure is mounted.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 1a Ultrasonic scanning part 1b Flexible cord 1c Connector part 10 Tip cap 11 Cap holding member 12 Ultrasonic transducer 13 Tube 14 Flexible shaft 15 Cable 16 Ultrasonic transducer 17 Acoustic matching layer 18 Backing material 19 Connecting member Reference Signs List 20 Rotating body 22 Mounting part 24 Coil

Claims (6)

[Claims] 1. A cylindrical housing is provided at a tip, an ultrasonic transducer having an ultrasonic vibrator is mounted in the housing, the ultrasonic transducer is connected to a rotating body, and the rotating body is rotationally driven. In the ultrasonic probe configured to perform ultrasonic scanning, the rotating body is provided with a mounting portion at a position deviated from the rotation center axis to the housing inner surface side, and the rotation center is rotated from the mounting portion. An ultrasonic probe, wherein a connecting member is provided to extend in a direction parallel to an axis, and the ultrasonic transducer is connected to the connecting member. 2. The ultrasonic probe according to claim 1, wherein a transmitting / receiving surface of the ultrasonic transducer is connected to the rotation transmitting member so as to face a plane substantially including a rotation center axis. 3. An ultrasonic wave according to claim 1, wherein a transmitting / receiving surface of said ultrasonic transducer is arranged at a position beyond a position of said rotation center axis from a connecting portion to said connecting member. probe. 4. The ultrasonic probe according to claim 1, wherein the connecting member is a relay board that connects an ultrasonic transducer of the ultrasonic transducer and a cable. 5. The ultrasonic probe according to claim 1, wherein a concave portion is formed on the back side of the backing material of the ultrasonic transducer, and the connecting member is fixed in the concave portion. 6. The ultrasonic probe according to claim 5, wherein the backing material has a configuration in which tapered surfaces are formed by cutting obliquely downward portions on both sides of the fixing portion of the connecting member.