JPS6227913A - Ultrasonic endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an ultrasonic endoscope, and more particularly to an improvement in a mechanism for rotating an ultrasonic transducer in an ultrasonic endoscope.

[Background of the invention]

Ultrasonic endoscopes are generally equipped with an ultrasonic transmitter/receiver device at the tip of an optical endoscope, and can not only optically observe the affected area but also obtain ultrasound images of the affected area. It looks like this.

The ultrasonic transmitting/receiving device includes a case having a space for accommodating an ultrasonic medium, a rotating shaft that is partially located within the accommodating space and rotatably held in the case, and a rotating shaft for preventing leakage of the ultrasonic medium. The apparatus includes a shaft sealing material provided between the case and the rotating shaft, and an ultrasonic vibrator supported by a portion of the rotating shaft within the accommodation space. The rotation of the ultrasonic transducer is achieved by connecting the rigid tip part with the rotary shaft of the electric motor in the operation part through a flexible tube, and causing the electric motor to rotate the rotary shaft. It is done by

In an endoscope, the rigid distal end needs to be miniaturized in order to facilitate insertion into a subject. However, it is difficult to miniaturize the shaft sealing material, so it is currently not possible to achieve sufficient size.

If the shaft sealing material is made smaller, its sealing performance will deteriorate, so the gap between the rotating shaft and the pole piece must be made smaller. In addition, in order to rotate the rotating shaft smoothly, it is necessary to connect the rotating shaft and the pole piece with n! It is necessary to provide a large gap. Therefore, in conventional ultrasonic endoscopes, bearings are disposed outside the surface of the shaft sealing material, the rotating shaft is held by these bearings, and the pole piece is released from holding the rotating shaft. However, even if the diameter of the rigid tip becomes smaller, the length of the rigid tip increases, so there still remains a problem in inserting the rigid tip into the object to be inspected.

[Object of the Invention] The present invention provides an improved ultrasonic endoscope in which the diameter and length of the rigid tip portion can be made smaller, and the insertion into a subject can be easily and painlessly performed. Our goal is to provide the following.

[Summary of the invention]

In the ultrasonic endoscope of the present invention, a sliding bearing for holding the rotating shaft is formed in a part of the mating hole of the pole piece constituting the shaft sealing material, and a sliding bearing for holding the rotating shaft is formed in a part of the pole piece. The remaining part seals the rotating shaft, and the bearing that holds the rotating shaft in conventional endoscopes is omitted, achieving downsizing and ensuring the necessary sealing performance. It is something.

Embodiments of the ultrasonic endoscope of the present invention will be described below with reference to the accompanying drawings.

[Embodiments of the invention]

FIG. 1 shows details of the rigid tip portion of this ultrasonic endoscope.

The case 11 is made of a material that transmits ultrasonic waves.

The rotating shaft 12 is held in the case 11 by a shaft sealing material 13. A sound wave absorber 15 made of rubber or the like is fixed to the end of the rotating shaft 12. The ultrasonic transducer 16 is disposed on a sound wave absorber and can rotate together with the rotating shaft 12.

The electrical connection between the ultrasonic transducer and the transmitter/receiver is provided by the contact plate 1.
7 and a contact block 18.

The contact plate 17 is engaged with and fixed to the rotating shaft 12.

The contact base 18 is made of spring steel, is positioned between the partition plate 19 and the contact plate 17, is fitted onto the rotating shaft 12, and is fixed to the partition plate 19 with machine screws 24.

The ultrasonic transducer 16 is connected to the contact plate 1 by wires 25, 26.
The transmitter/receiver connected to 7 and transmitting and receiving ultrasonic waves to and from the transducer 16 is connected to the contact block 18 on the partition plate, and is electrically connected to each other through the contacts on the contact block 18 and the contacts on the contact plate 17. I'm forced to.

An ultrasonic medium 21 is filled in a chamber 22 formed in the case 11 by the shaft sealing material 13, and the ultrasonic transducer is rotated within this ultrasonic medium.

In order to fill the medium, the member 23 holding the rotating shaft 12 is screwed into a screw hole in the end wall of the case 11 with a gasket 24' interposed.

As clearly shown in FIG. 2, the shaft sealing material 13 is
It is equipped with two pole pieces 25 and 26.

Each pole piece is formed in the form of a thick disc with a central hole. Among these, the hole of the pole piece 25 has two hole portions 27. which have different diameters and are coaxially arranged.
28, and the hole in the pole piece 26 is separated by a groove 29 and has two coaxially arranged hole portions 31.
．． It consists of 32.

The permanent magnet 33 is disk-shaped and has a hole in the center with a diameter larger than that of the hole portion 28.31, and the pole pieces 25 and 2
6 and are arranged with their central axes aligned with each other,
It is integrated with these pole pieces by adhesive or the like.

In this laminate, the hole portion 27 is fitted to the large diameter portion of the rotating shaft 12, and the hole portions 28, 31, 32 are fitted to the small diameter portion of the rotating shaft 12. The hole portion 27.32 of the pole piece is the rotation axis 1
2, and the rotating shaft 12 is held by these sliding bearings. but,
A gap between the hole portion 28.31 and the rotating shaft 12 is wider than that of the plain bearing.

Magnetic 1 No 1 Fluid 34. :(5 is disposed in the gap between the hole portion 28.3+ and the rotating shaft 12. The magnetic fluid itself is made of metal magnetic fluid, and the magnetic fluid flows from the N pole of the magnet 33 to the pole piece 25, the rotation III 112, pole piece 2
6 to the magnet 33(7) 14j
By means of the hole portion 28. :(It is held in the gap between l and the rotating shaft 12, and seals these gaps.

The rigid tip portion having such a shaft sealing material can itself be configured extremely compactly. That is, since the axis of rotation 12 is supported by a plain bearing formed by the bore part 28.31, that is, the axis of rotation 12 is supported by the pole piece 25.26 and the bearing can be moved to the pole like in a conventional endoscope. This is because since there is no need to add it to the outside of the piece, not only the diameter of the rigid tip portion but also the overall length can be configured to be short.

Furthermore, these edge bearings are connected to the pole pieces 25, 2
6 and permanent magnet: (After gluing 3, the hole part 27° 3
2 can be formed by adding 1- with the hole portions 28 and 31, so manufacturing can be done with precision and ease, and there is no misalignment of the bearings in conventional endoscopes. , the ultrasonic transducer 16 can be rotated stably.

Furthermore, the gap between the rotating shaft 12 and the hole portion 28.31 of the pole piece 25.26, that is, the gap filled with the magnetic fluid 34. Since the size can be selected to maximize performance, it can have excellent sealing performance.

Is this Φ mountain sealing material suitable? Yes, pole piece 25.26
The surface of the hole portion 27.32 that holds the rotating shaft 12 in is provided with a layer made of a material having a low coefficient of friction with the rotating shaft 12, so that the rotating shaft 12 can rotate 1φ1 in a more stable state. be able to. This is, for example,
The surfaces of the hole portions 27 and 32 are coated with polytetrafluoroethylene resin to form a bearing layer for the rotating shaft 12, or bushings made of such resin are fitted and fixed in these hole portions. This is accomplished by interposing these bearing layers or bushes to hold the rotating shaft on the pole piece.

This rigid distal end portion constitutes an endoscope as shown in FIG. In the figure, the entire tip rigid part is numbered 4.
1, it is connected to a flexible tube 43 via a member 42 fixed to the case 11, and connected to an operating section 44 by this flexible tube. The operation knob 45 has a rigid tip portion 4
1 and the flexible tube 43, and by rotating the knob, the rigid distal end portion can be bent from the curved portion 46. The main body 47 has a built-in transmitter/receiver that allows the transducer to transmit and receive ultrasonic waves, a cathode ray tube that displays ultrasonic images, etc., and the ultrasonic transducer in the rigid tip part 42 is connected to the cable 48 and the wire passing through the flexible tube. It is connected to the.

The observation window 49 of the optical observation device is connected to the window 31 in the member 4 by an optical fiber passing through the flexible tube 4:3 and the operating part 44.

The rotating shaft 12 supporting the ultrasonic transducer is rotated by an electric motor 5I built into the operating section 44. For this purpose, a flexible shirt 1-52 is passed through the inside of the flexible tube 43, as shown in FIG. This flexible shaft 52 has both ends connected to the rotating shaft 12 and the rotating shaft of the electric motor 51.

In this endoscope, the flexible shaft 52 is connected to the operating section 4.
4 and the rigid tip portion 41, a flexible tube 5 is provided to protect the wire etc. from rotation of the flexible shaft.
It is arranged so as to penetrate the inside of 3. The flexible tube 53 is provided with a support 55 between it and the flexible shirt 1 52. These supports are
The hollow holes of the flexible tube 53 have an annular shape with a substantially triangular cross section arranged at equal intervals along the longitudinal direction of the hollow hole, and are formed integrally with the flexible tube 53. The flexible shaft 52 is rotatably held by these supports 55. For this reason, the flexible shaft 52 is free from lateral vibrations that occur during rotation.
In other words, the vibration in the direction perpendicular to the central axis = 10- of the flexible shaft 52 becomes extremely small, allowing the ultrasonic transducer 16 to rotate smoothly at a constant angular velocity.

These supports may, on the contrary, be fixed to the flexible shaft. In this case, the support is formed by, for example, wrapping a ribbon or tape made of a heat-shrinkable synthetic resin around the flexible shaft until the diameter is approximately equal to the diameter of the hollow hole of the flexible tube, and fixing the ribbon or tape to the flexible shaft. Such supports are provided along the flexible shaft at regular intervals, and the flexible shaft is supported on the flexible tube by these supports so as to rotate together with the supports within the flexible tube. It will be done.

Diagnosis using this ultrasound endoscope is, for example, for diagnosis of the stomach.
The rigid tip portion 41 is bent from the curved portion 46 by the knob 45, the rigid tip portion 41 is inserted into the mouth of the subject, and the optical m
This is done by finding the diagnostic site through the detection window 49 and displaying an image of the diagnostic site using ultrasound on a cathode ray tube in the main body 47.

Observation using ultrasonic waves is performed by rotating the electric motor 51. When the electric motor 51 is rotated, the rotating shaft 1
2 is rotated inside the case 11 by a flexible shaft 52, and the ultrasonic transducer 16 is electrically connected to the transceiver via the contact plate 17 and the contact base 18, and transmits and receives ultrasonic waves. , the ultrasonic image is displayed on the display device in the main body 47. The timing of transmitting and receiving ultrasonic waves is determined by the rotation angle detector in the case 11.
This is done by outputting a signal by detecting the rotation angle of 2.

In this diagnosis, the ultrasonic endoscope according to the present invention has a small diameter and length of the rigid distal end as described above, so it is possible to perform this diagnosis without causing pain to the subject. can be inserted into the object to be inspected. Further, since lateral vibration of the flexible shaft is prevented and the ultrasonic transducer can rotate smoothly with a constant angular velocity, it is possible to obtain an ultrasonic image without blur.

〔Effect of the invention〕

11- As described above, in the ultrasonic endoscope of the present invention, the rotating shaft that supports the ultrasonic transducer is supported by a flat bearing formed by the hole of the pole piece. Since there is no need to add a bearing to the outside of the pole piece as in conventional endoscopes, the rigid tip can be configured extremely compactly, making it easy to insert the rigid tip into the object to be inspected. It can be done quickly and without causing any pain. In addition, the sliding bearing can be machined together with the hole that holds the magnetic fluid when machining the pole piece, making it not only easy to manufacture, but also highly accurate, allowing ultrasonic vibration The child can be rotated stably, and stable ultrasound images without distortion can be obtained.

[Brief explanation of the drawing]

The drawing shows an embodiment of the ultrasonic endoscope of the present invention,
Figure 1 is a sectional view of the rigid tip part, Figure 2 is an enlarged sectional view of the shaft sealing material incorporated in the rigid tip part, Figure 3 is a front view showing the overall configuration of the ultrasonic endoscope, and Figure 4. is a sectional view of the flexible shaft. DESCRIPTION OF SYMBOLS 11... Case, 12... Rotating shaft, 13... Shaft sealing material, 16... Ultrasonic vibrator, 21... Ultrasonic medium, 22... Accommodation space for ultrasonic medium, 25. 26...
Pole piece, 27.32...Sliding bearing, 33...
・Magnet, 34.35...Magnetic fluid, 41...Hard tip part. Patent applicant Hitachi Medical Co., Ltd. Patent attorney
Autumn Masamoto Actual Figure 1 Knee'' -, --- □--7 Figure 2 M9 Figure 3

Claims (1)

[Claims] 1. A case having a space in which the rigid tip portion to be inserted into the object to be inspected accommodates an ultrasonic medium, and a rotating shaft that is partially located within the accommodation space and rotatably held in the case; The apparatus includes a shaft sealing material provided between the case and the rotating shaft to prevent leakage of the ultrasonic medium, and an ultrasonic vibrator supported by a portion of the rotating shaft within the housing space. In an ultrasonic endoscope, the shaft sealing material applies a magnetic field to at least two pole pieces that are mated with the rotating shaft with a gap formed between them, and the gap between the rotating shaft and the pole pieces. A magnet is disposed between the pole pieces to form a magnet, and a magnetic fluid is disposed in each gap between the pole piece and the rotating shaft. An ultrasonic endoscope characterized by forming a sliding bearing that holds a rotating shaft.