JP2003159251A - Ultrasonic endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic endoscope which allows the reduction in the size of a distal end while having an ultrasonic transducer, a slip ring, a motor reducer, a motor, and an encoder in the distal end. <P>SOLUTION: The ultrasonic endoscope, which is equipped with the ultrasonic transducer 21, the slip ring 22, the motor reducer 32, the motor 33, and the encoder 34 and scans a celom by rotating the ultrasonic transducer 21 mechanically, is provided with output shafts 33a, 33b at both ends of the motor 33, respectively, and has the ultrasonic transducer 21, the slip ring 22, the motor reducer 32, the motor 33, and the encoder 34 placed in series in this order from the tip in the distal end. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic endoscope having an ultrasonic transducer at the tip of an insertion section.

[0002]

2. Description of the Related Art In recent years, an ultrasonic endoscope which mechanically rotates ultrasonic vibrations oscillated from an ultrasonic transducer to scan the inside of a body cavity and diagnose a lesion or the like in the body cavity by an ultrasonic tomographic image. Various ultrasonic vibration devices such as an ultrasonic probe and an ultrasonic probe have been proposed. For example, as an example of an ultrasonic endoscope generally known in the past, there is one shown in FIGS.

FIG. 15 is an overall view of a conventional ultrasonic endoscope, FIG. 16 is a longitudinal sectional view of a sub operation portion of the ultrasonic endoscope, and FIG.
16 is a sectional view taken along line XVII-XVII in FIG. 16, and FIG. 18 is a longitudinal sectional view of the distal end portion of the ultrasonic endoscope.

As shown in FIG. 15, the ultrasonic endoscope 101 includes an insertion portion 102 to be inserted into a body cavity, and an operation portion 105 and a sub-operation portion 106 provided at the rear end of the insertion portion 102. A universal cord 107 configured to be connected to a light source device (not shown) from the operation unit 105, and an ultrasonic cord connected to an ultrasonic observation device (not shown) from the sub-operation unit 106. 108 extend respectively.

Further, the insertion portion 102 is provided with a bending tube 103 and a tip portion 104 at its tip, and the bending tube 103 can operate a bending knob 109 provided in the operation portion 105. Is formed to be bendable.

As shown in FIGS. 16 and 17, a drive device 110 is arranged inside the sub operation unit 106. The driving device 110 includes a flexible shaft 120.
A motor 111 for rotating the motor, an encoder 112 for detecting the rotational position of the motor 111, and a slip ring 113.
It is mainly composed of and.

The rotation of the motor 111 is performed by the timing belt 114 by the encoder 112 and the slip ring 1.
13 and the rotation in the radial direction perpendicular to the insertion direction of the insertion portion 102 is transmitted to the distal end portion 104 via the flexible shaft 120.

As shown in FIG. 18, the tip portion 104 includes a tip body 121, a tip cap 122, and
The ultrasonic transducer 123 is mainly included.

The tip body 121 has a structure in which the tip is covered with the tip cap 122, and the region surrounded by the tip body 121 and the tip cap 122 is filled with an ultrasonic transmission medium 124. Has been done.

The tip body 121 and the tip cap 12
An ultrasonic transducer 123 is fixedly provided by a transducer holding member 125 in a region surrounded by 2 and. Further, the vibrator holding member 125 is rotatably supported by the tip end main body 121 so as to be rotatable in a radial direction coaxial with the flexible shaft 120 and perpendicular to the insertion direction of the insertion section 102.

Further, a through hole 121a is provided in the tip body 121, and the vibrator holding member 125 and the flexible shaft 120 are connected in the through hole 121a of the tip body 121. . That is, the ultrasonic oscillator 123 is connected to the flexible shaft 120 via the oscillator holding member 125.

The inside of the flexible shaft 120 is hollow. Inside the flexible shaft 120, a coaxial cable (not shown) whose distal end side is connected to the ultrasonic transducer 123 is inserted, and the proximal end side of this coaxial cable is connected to the slip ring 113. ing.

In addition, paragraph 12 is provided on the tip body 121.
1b is formed, and a ball bearing 126 for stably rotating the vibrator holding member 125 is arranged in this paragraph 121b.

With this structure, the ultrasonic endoscope 101 operates the driving device 110, and the ultrasonic transducer 123 is inserted through the flexible shaft 120.
The radial scanning is performed in a radial direction perpendicular to the inserting direction of 02 to take a tomographic image in a direction perpendicular to the inserting direction of the inserting section 102 to perform radial scanning.

However, in the conventional ultrasonic endoscope 101 configured as described above, the operator always operates the motor 111, the encoder 112, and the slip ring 113 during the examination.
Since it is necessary to continue to hold the sub-operation unit 106 in which the is built in, the operator's burden is heavy.

Further, since the ultrasonic transducer 123 is rotated through the flexible shaft 120, the flexible shaft is inserted while the endoscope is inserted into the body cavity for ultrasonic examination. When the twist occurs in 120, a phase shift occurs between the encoder 112 in the sub-operation unit 106 and the ultrasonic transducer 123 in the tip portion 104, causing a problem such as shaking or distortion on the ultrasonic image. Cause

Therefore, in Japanese Unexamined Patent Publication No. 2001-128981, as shown in FIG. 19, an ultrasonic transducer 131, a slip ring 132, and an encoder 133 are provided at the tip.
And the motor 134 with a decelerator are arranged in this order in series from the distal end side.

[0018]

By the way, the ultrasonic endoscope is required to have its tip as small as possible in order to reduce the burden on the patient during observation. However, the ultrasonic endoscope disclosed in JP 2001-128981 A has a problem in that it is difficult to reduce the size of the tip because the encoder cannot be made small.

That is, the encoder is selected to have a disk in which the same number of slits as the number of pulses to be detected are formed, the disk is attached to the rotating body, and the slit of the disk is read by the sensor to rotate the rotating body. It has a structure to detect the position. Therefore, the size of the encoder is determined by the size of the disk, that is, the number of slits formed in the disk.

In addition, by the encoder, 1 per rotation
A signal that is pulse-detected and gives direction information of the rotating body is Z
A signal, which is detected by a large number of pulses in one rotation in one phase and gives angular velocity information of the rotating body, is called A and B phases. Generally, it is necessary to detect about 300 pulses of A and B phases for ultrasonic image construction.

In the ultrasonic endoscope disclosed in Japanese Unexamined Patent Publication No. 2001-128981, the disk of the encoder 133 is attached to the output shaft of the motor 134 with a decelerator, and the slit of the disk is read by a sensor, whereby the decelerator with the decelerator is attached. The structure is such that the rotational position of the motor 134 is detected. Therefore, in the ultrasonic endoscope disclosed in Japanese Unexamined Patent Application Publication No. 2001-128981, the rotational position of the motor 134 with a decelerator must be detected by using the encoder 133 in which about 300 slits are formed on the disk.

Therefore, the above-mentioned Japanese Patent Laid-Open No. 2001-1289
Encoder 13 used in the ultrasonic endoscope disclosed in Japanese Patent No. 81
No. 3 has a size capable of forming about 300 slits on the disk, and the encoder 133 cannot be made small, so that it is difficult to miniaturize the tip of the ultrasonic endoscope.

The present invention provides an ultrasonic endoscope in which an ultrasonic transducer, a slip ring, a motor speed reducer, a motor and an encoder are arranged at the tip, but the tip can be miniaturized. With the goal.

[0024]

An ultrasonic endoscope according to the present invention is provided with an ultrasonic vibrator, a slip ring, a motor speed reducer, a motor and an encoder at a distal end thereof, and the ultrasonic vibrator is mechanically operated. An ultrasonic endoscope that scans the inside of a body cavity by rotating, wherein a hard tip portion provided at the distal end portion is provided with motors having output shafts at both ends thereof, The acoustic wave vibrator, the slip ring, the motor speed reducer, the motor, and the encoder are arranged in series in this order.

In the ultrasonic endoscope of the present invention, a motor having output shafts at both ends is provided in the distal end hard portion, and a motor speed reducer, a slip ring and an ultrasonic transducer are disposed at the distal end side of the motor. An encoder is arranged on the base end side opposite to the front end side.

That is, the ultrasonic endoscope of the present invention is configured to detect the rotation of the motor before being decelerated by the motor decelerator by the encoder. Therefore, the encoder used in the ultrasonic endoscope of the present invention can have a smaller number of slits in the disk than the encoder used in the conventional ultrasonic endoscope, and the disk can be made smaller.

Therefore, according to the ultrasonic endoscope of the present invention, the ultrasonic vibrator, the slip ring, the motor speed reducer, the motor, and the encoder are arranged at the tip, but the tip can be miniaturized. it can.

In the ultrasonic endoscope of the present invention, at least the ultrasonic transducer, the slip ring, the motor speed reducer, the motor and the encoder are integrated to form an ultrasonic scanning unit, and at the same time, the ultrasonic scanning unit is provided. It is preferable to provide a mechanism for correcting the provided ultrasonic transducer in a predetermined direction with respect to the hard tip portion.

[0029]

1 to 9 show a first embodiment of the present invention. FIG. 1 is an overall view of an ultrasonic endoscope, and FIG. 2 is a tip portion of the ultrasonic endoscope. 2 is a longitudinal sectional view of FIG.
3 is a sectional view taken along line III-III of FIG. 4, FIG. 4 is a longitudinal sectional view of the encoder, FIG. 5 is a sectional view taken along line VV of FIG. 4, and FIG. 6 is a longitudinal sectional view of the ultrasonic scanning unit and the distal end hard portion. , FIG. 7 is VI of FIG.
8 is a sectional view taken along line I-VII, FIG. 8 is a view showing a mechanism for uniquely determining the relative positional relationship between the ultrasonic transducer and the housing, and FIG. 9 is a sectional view taken along line IX-IX in FIG. Is.

As shown in FIG. 1, the ultrasonic endoscope 1 of this embodiment is composed of an insertion portion 2 to be inserted into a body cavity and an operation portion 5 provided at the rear end of the insertion portion 2. And
A universal cord 6 connected to the light source device and the ultrasonic measuring device (not shown) respectively extends from the operation section 5. A control device for controlling and driving an ultrasonic scanning unit 20 described later is provided in the ultrasonic measuring device.

The insertion section 2 is provided with a bending tube 3 and a tip section 4 at its tip, and the bending tube 3 is bent by operating a bending knob 7 provided on the operation section 5. It is formed freely.

Further, as shown in FIGS. 2 and 6, the tip end portion 4 is made of a hard material, and the tip end hard portion 1 is formed.
0 and an ultrasonic scanning unit 20 mounted on the tip hard portion 10.

An illumination optical system 11 and an observation optical system 12 are provided in the distal end hard portion 10 as an endoscope optical system in a diagonally forward direction.

The illumination optical system 11 comprises a light guide (not shown) for transmitting the illumination light and an illumination lens (not shown) for expanding and emitting the illumination light, and goes diagonally forward through the illumination lens. Illumination light is emitted to illuminate an object such as a lesion in the body cavity.

The observation optical system 12 has an objective lens 13 which forms an optical image of an illuminated object and an image guide 14 whose front end surface is located at an image forming position. The image guide 14 forms an optical image. Transmit to the rear end face.

Further, the tip end hard portion 10 is provided therein with an accommodation space for accommodating a motor unit 31 described later.

On the other hand, the ultrasonic scanning unit 20 includes an ultrasonic transducer 21, a slip ring 22, a motor speed reducer 32, a motor 33, an encoder 34, a connector 37a, a housing 23, and a tip cap 24. It is mainly composed of and.

The housing 23 has a structure in which its tip is covered with a tip cap 24.
The region surrounded by 3 and the tip cap 24 is filled with the ultrasonic transmission medium 27.

An ultrasonic transducer 21 is fixedly provided by a transducer holding member 25 and a transducer shaft 26 in a region surrounded by the housing 23 and the tip cap 24. Further, the vibrator shaft 26 is
Ball bearing 28 provided in the housing 23
Is rotatably supported in a radial direction perpendicular to the insertion direction of the insertion portion 2 and is watertightly secured by an O-ring 29.

In this way, the ultrasonic transducer 21 has a structure capable of performing radial scanning for taking a tomographic image in a direction perpendicular to the inserting direction of the inserting section 2.

Further, the slip ring 22 is also provided in the area surrounded by the housing 23 and the tip cap 24. The slip ring 22 is connected to the ultrasonic oscillator 21 via a coaxial cable 30, and signals from the ultrasonic oscillator 21 are transmitted through the coaxial cable 30, the slip ring 22, and a coaxial cable (not shown). It is transmitted through to the connector 37a.

Further, the motor decelerator 32 and the motor 33
The encoder 34 and the connector 35 are integrated to form a motor unit 31.

The motor 33 is a small motor having output shafts 33a and 33b at both ends. The output from the output shaft 33a on the front end side of the motor 33 is transmitted to the vibrator shaft 26 via the shaft 38 and the shaft coupling 39 after being decelerated by the motor speed reducer 32.
The ultrasonic transducer 21 is rotated in a radial direction perpendicular to the insertion direction of the insertion section 2.

The motor decelerator 32 is used to convert the rotational speed and the torque into appropriate values, since a small motor generally has a large rotational speed and a small torque.

The encoder 34 detects the rotational position of the motor 33, and is directly attached to the output shaft 33b on the base end side of the motor 33. Also, the signal from the encoder 34 enters the connector 37a.

The shaft 38 and the oscillator shaft 2
6 is connected via a joint shaft 39, and the motor unit 31 is mounted in the housing 23, whereby the ultrasonic transducer 21, the slip ring 22, and the motor speed reducer 32 are connected.
, Motor 33, encoder 34, and connector 37a
The housing 23 and the tip cap 24 are integrated with each other to form the ultrasonic scanning unit 20. Further, by accommodating the motor unit 31 of the transducer unit 20 in the accommodation space of the tip rigid portion 10 and detachably mounting the transducer unit 20 on the tip rigid portion 10, the ultrasonic endoscope of this embodiment is shown. The mirror 1 is formed.

The signal coaxial cable of the ultrasonic transducer, the signal cable of the encoder, and the power supply cable of the motor, which are not shown, are all connected to the connector 37a. Further, the tip rigid portion 10 is provided with a connector 37b, and the ultrasonic scanning unit 20 is attached to the tip rigid portion 10.
At the same time, the connector 37a contacts the connector 37b and is electrically connected. The connector 37b is connected to the cable 15, and the cable 15 is inserted through the insertion section 2, the operation section 5 and the universal cord 6 and connected to the ultrasonic observation apparatus.

Next, the encoder 34 will be described with reference to FIGS. The encoder 34 used in the ultrasonic endoscope of this embodiment is, for example, an encoder that detects the rotation of the motor 33 for one pulse during one rotation, and includes the disk 35 having the slit 35a and the sensor 3.
It consists of 6 and 6.

In the ultrasonic endoscope 1 of this embodiment, the disk 35 of the encoder 34 is attached to the output shaft 33b of the motor 33 on the base end side, and the slit 35a of the disk 35 is read by the sensor 36. By this, the rotational position of the motor 33 is detected.

That is, since the encoder 34 used in the ultrasonic endoscope 1 detects the rotation of the motor 33 before being decelerated by the motor decelerator 32, the encoder of the conventional ultrasonic endoscope is used. Compared with, the number of slits in the disk may be smaller, and the disk can be made smaller.

That is, as described in the section [Problems to be Solved by the Invention], it is necessary to detect about 300 pulses of A and B phases in constructing an ultrasonic image.

In the ultrasonic endoscope 1 of this embodiment, as described above, since the encoder 34 detects the rotation of the motor 33 before being decelerated by the motor decelerator 32, one pulse is generated during one rotation. Even if the encoder 34 that detects the degree of rotation is used, the motor speed reducer 3 having a reduction ratio of about 1/300
When combined with 2, the vibrator shaft 26
With respect to the above, angular velocity information equivalent to that in the case where an encoder capable of detecting rotation of about 300 pulses is connected to the motor with a decelerator is obtained.

Therefore, the encoder 34 used in the ultrasonic endoscope 1 of this embodiment can have a smaller disk than the encoder of the conventional ultrasonic endoscope.

The ultrasonic endoscope 1 of this embodiment is
Since the small encoder 34 that detects rotation of about 1 pulse per rotation is used, the A and B phases can be detected, but the Z phase cannot be obtained. That is, although the angle information regarding the rotation of the ultrasonic transducer 21 can be obtained, the orientation information of the ultrasonic transducer 21 cannot be obtained.

However, when constructing an ultrasonic image, in order to grasp the relative orientation relationship between the ultrasonic image obtained by the endoscope and the ultrasonic endoscope, the orientation information of the ultrasonic transducer 21 is obtained. Is essential. This is for the surgeon to understand what direction the ultrasonic image has in relation to the endoscopic image during the ultrasonic image diagnosis.

Therefore, the ultrasonic endoscope 1 is provided with a mechanism for correcting the ultrasonic transducer 21 provided in the ultrasonic scanning unit 20 in a predetermined direction with respect to the distal end hard portion 10.

A mechanism for correcting the ultrasonic transducer 21 provided in the ultrasonic scanning unit 20 in a predetermined direction with respect to the distal end hard portion 10 will be described below with reference to FIGS. 6 to 9.

In the ultrasonic endoscope 1 of this embodiment, for example, a mechanism for uniquely determining the relative positional relationship between the ultrasonic transducer 21 and the housing 23 is provided, and the housing 23 and the distal end hard portion 10 are provided. The ultrasonic transducer 21 is formed so as to correct the distal end hard portion 10 in a predetermined direction by providing a mechanism that uniquely determines the relative positional relationship with the ultrasonic transducer 21.

First, the ultrasonic transducer 21 and the housing 23
A mechanism for uniquely determining the relative positional relationship with will be described with reference to FIGS. 7 and 8.

As described above, the shaft 38 transmits the rotation of the motor 33 decelerated by the motor reducer 32 to the ultrasonic transducer 21, and the ultrasonic wave is transmitted via the shaft coupling 39 and the transducer shaft 26. It is connected to the oscillator 21.

Therefore, in this ultrasonic endoscope 1, the relative positional relationship between the ultrasonic transducer 21 and the housing 23 is determined by uniquely determining the relative positional relationship between the shaft 38 and the housing 23. Can be uniquely determined.

The cross section of the shaft 38 is
It is formed in a D shape with a part of the circle cut out, and a gear 38a is provided in the arc portion thereof.

In the housing 23, the insertion portion 2
The rack 40 orthogonal to the insertion direction of the
It is arranged so that it can be freely inserted into and removed from the inside of 3. The rack 40 is arranged at a position corresponding to the shaft 38, and a tooth portion 40a that meshes with a gear 38a of the shaft 38 is provided at the tip of the rack 40. The length of the tooth portion 40a of the rack 40 is substantially equal to the length of the arc portion of the shaft 38.

Therefore, when the rack 40 is inserted into the housing 23, the gear 38a of the shaft 38 meshes with the tooth portion 40a of the rack 40, and the shaft 38 rotates. Then, as shown in FIG. 8, when the tooth portion 40a of the rack 40 faces the flat portion of the shaft 38 (the portion where a part of the circle is omitted), the gear 38a of the shaft 38 and the tooth portion 40a of the rack 40. Will not mesh with each other, and the rotation of the shaft 38 will stop.

As described above, the relative positional relationship between the shaft 38 and the housing 23 is such that the rotation of the shaft 38 is stopped because the gear 38a of the shaft 38 and the tooth portion 40a of the rack 40 do not mesh with each other. Uniquely determined.

As shown in FIG. 8, when the rack 40 is completely inserted into the housing 23 and the transducer scanning unit 20 is attached to the distal end hard portion 10, the rack 40 has the housing 23 and the distal end hard portion. Since it is fixed by the portion 10, the rack 40 does not hinder the rotation of the shaft 38.

Next, regarding the mechanism for uniquely determining the relative positional relationship between the housing 23 and the distal end hard portion 10,
This will be described with reference to FIGS. 6 and 9.

The housing 23 is provided with a positioning pin 23a as shown in FIG. 6, and the distal end hard portion 10 is provided with the positioning pin 23 as shown in FIGS.
A groove 10a for fitting with a is provided.

Therefore, when the ultrasonic scanning unit 20 is attached to the hard tip 10, the positioning pin 23a and the groove 10a are fitted to each other, and the housing 23 and the hard tip 10 are fitted.
The relative positional relationship with is uniquely determined. The ultrasonic scanning unit 20 and the distal end hard portion 10 are detachable because they are fitted by fitting the positioning pin 23a and the groove 10a.

Further, in this ultrasonic endoscope 1, the relative orientation information of the ultrasonic transducer 21 with respect to the distal end hard portion 10 is stored in the ultrasonic endoscope 1 by a memory (not shown). Is formed in. Hereinafter, a method of grasping the relative orientation relationship between the ultrasonic image and the ultrasonic endoscope 1 will be described.

First, the ultrasonic transducer 2 after the ultrasonic transducer 21 is corrected in a predetermined direction with respect to the distal end hard portion 10 is described.
The relative orientation information of 1 is stored in the memory.

After that, every time the ultrasonic transducer 21 stops rotating, the memory stores the orientation information of the ultrasonic transducer 21 with respect to the distal end hard portion 10 at the time of stopping.

Then, when the rotation of the ultrasonic transducer 21 is started, the orientation information of the ultrasonic transducer 21 with respect to the distal end hard portion 10 at the time when the rotation of the ultrasonic transducer 21 is stopped last time is read from the memory. By doing so, the relative orientation relationship between the ultrasonic image and the ultrasonic endoscope 1 is grasped.

As described above, in the ultrasonic endoscope 1, the tip hard portion 10 provided on the tip portion 2 is provided with the motor 33 having output shafts 33a and 33b at both ends,
The ultrasonic transducer 21, the slip ring 22, the motor reducer 32, the motor 33, and the encoder 34 are arranged in series in this order from the tip side of the tip 4.

That is, in this ultrasonic endoscope 1, the motor speed reducer 32 and the slip ring 22 are provided on the tip side of the motor 33.
And the ultrasonic transducer 21 are arranged, and the motor 33
By arranging the encoder 34 on the proximal end side, the rotation of the motor 33 before being decelerated by the motor decelerator 32 by the encoder 34 is detected.

Therefore, the ultrasonic endoscope 1 of this embodiment is
The encoder 34 used in 1) can reduce the number of slits in the disk and can make the disk smaller than the encoder used in the conventional ultrasonic endoscope.

Therefore, according to the ultrasonic endoscope 1 of this embodiment, although the ultrasonic transducer 21, the slip ring 22, the motor speed reducer 32, the motor 33 and the encoder 34 are arranged at the tip, The tip can be miniaturized.

Further, the ultrasonic endoscope 1 of this embodiment is
The ultrasonic transducer 21, the slip ring 22, the motor speed reducer 32, the motor 33, the encoder 34, the connector 37a, the housing 23, and the tip cap 24 are integrated to form the ultrasonic scanning unit 20. In addition, since the mechanism for correcting the ultrasonic transducer 21 provided in the ultrasonic scanning unit 20 in the predetermined direction with respect to the distal end hard portion 20 is provided, the relative endoscopic image and ultrasonic image are compared. It is possible to easily grasp the specific orientation relationship.

10 to 14 show a second embodiment of the present invention, FIG. 10 is a side view of a motor unit of an ultrasonic endoscope, and FIG. 11 is a cross section taken along line XI-XI of FIG. Figure,
12 is a vertical sectional view before mounting the motor unit on the housing, FIG. 13 is a sectional view taken along line XIII-XIII in FIG. 12,
FIG. 14 is a vertical cross-sectional view of the motor unit mounted on the housing.

In the ultrasonic endoscope 1 of this embodiment, the ultrasonic transducer 21 and the housing 2 are determined by uniquely determining the relative positional relationship between the shaft coupling 39 and the housing 23.
It is intended to uniquely determine the relative positional relationship with respect to 3.

As shown in FIGS. 10 and 11, the shaft coupling 39 is provided with a D-shaped hole 39a and a groove 39b.

Further, as shown in FIGS. 12 and 13,
The oscillator shaft 26 is formed in a D-shape whose cross section is fitted in the hole 39a of the shaft coupling 39.

Further, as shown in FIG. 12, the housing 23 is provided with a positioning pin 23b which fits into the groove 39b of the shaft coupling 39. Since the other configurations are the same as those of the above-described first embodiment, the duplicate description will be omitted by giving the same reference numerals to the drawings.

In the ultrasonic endoscope 1 of this embodiment, the hole 39a of the shaft coupling 39 and the transducer shaft 26 are fitted together, and the groove 39b of the shaft coupling 39 and the positioning pin 23b of the housing 23 are fitted. 12 and 14, the motor unit 31 is attached to the housing 23 to form the transducer unit 20.

Further, the shaft coupling 39 is connected to the ultrasonic oscillator 21 via the oscillator shaft 26. Therefore, as described above, by uniquely determining the relative positional relationship between the shaft coupling 39 and the housing 23, the relative positional relationship between the ultrasonic transducer 21 and the housing 23 is uniquely determined. You can decide.

The vibrator scanning unit 2 is shown in FIG.
When 00 is completely attached to the distal end hard portion 10, the positioning pin 23b of the housing 23 penetrates the groove 39b of the joint shaft 39, so that the positioning pin 23b does not hinder the rotation of the shaft 38 and the joint shaft 39. There is no.

Therefore, in the ultrasonic endoscope 1 of this embodiment, the same effect as that of the first embodiment can be obtained.

In the first and second embodiments described above, an encoder that detects rotation of about one pulse during the rotation of the motor 331 is used as the encoder 34, and the motor reduction gear 32 has a reduction ratio of about 1/300. Although the speed reducer is used, the encoder 34 and the motor speed reducer 32 are not limited to this.

Further, the ultrasonic endoscope of the present invention controls the angle of the transducer shaft by using the angle information regarding the rotation of the ultrasonic transducer obtained by detecting the A and B phases by the encoder. It can also be applied to an ultrasonic endoscope configured to perform.

[0090]

As described above, according to the invention of claim 1, although the ultrasonic transducer, the slip ring, the motor reducer, the motor and the encoder are arranged at the tip, the tip is small. Can be converted.

According to the second aspect of the invention, it is possible to grasp the relative orientation relationship between the endoscopic image and the ultrasonic image.

[Brief description of drawings]

FIG. 1 is an overall view of an ultrasonic endoscope showing a first embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of the distal end portion of the ultrasonic endoscope according to the first embodiment.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a vertical cross-sectional view of the encoder according to the first embodiment.

5 is a cross-sectional view taken along the line VV of FIG.

FIG. 6 is a vertical cross-sectional view of the ultrasonic scanning unit according to the first embodiment and a hard tip portion.

7 is a sectional view taken along line VII-VII of FIG.

FIG. 8 is an explanatory diagram of a mechanism that uniquely determines the relative positional relationship between the ultrasonic transducer and the housing according to the first embodiment.

9 is a sectional view taken along the line IX-IX in FIG.

FIG. 10 is a side view of a motor unit of an ultrasonic endoscope showing a second embodiment of the present invention.

11 is a cross-sectional view taken along the line XI-XI of FIG.

FIG. 12 is a vertical cross-sectional view before mounting the motor unit of the second embodiment on a housing.

13 is a sectional view taken along line XIII-XIII in FIG.

FIG. 14 is a vertical cross-sectional view of the motor unit according to the second embodiment mounted on a housing.

FIG. 15 is an overall view of a conventional ultrasonic endoscope.

FIG. 16 is a vertical cross-sectional view of a sub operation unit of a conventional ultrasonic endoscope.

17 is a sectional view taken along line XVII-XVII in FIG.

FIG. 18 is a vertical cross-sectional view of a tip portion of a conventional ultrasonic endoscope.

FIG. 19 is a vertical cross-sectional view of the tip portion of another conventional ultrasonic endoscope.

[Explanation of symbols]

1. Ultrasound endoscope 2 ... insertion part 4 ... Tip 10 ... Hard end 20 ... Ultrasonic scanning unit 21 ... Ultrasonic transducer 22 ... Slip ring 23 ... Housing 31 ... Motor unit 32 ... Motor reducer 33 ... Motor 33a, 33b ... Output shaft 34 ... Encoder

Claims (2)

[Claims] 1. An ultrasonic endoscope in which an ultrasonic transducer, a slip ring, a motor speed reducer, a motor and an encoder are provided at a distal end portion, and the ultrasonic transducer mechanically rotates to scan the inside of a body cavity. The tip hard portion provided at the tip portion is provided with a motor having output shafts at both ends, and the ultrasonic transducer, the slip ring, the motor speed reducer, and the motor are provided from the tip end side of the tip portion. An ultrasonic endoscope in which the encoder and the encoder are arranged in series in this order. 2. An ultrasonic scanning unit is formed by integrating at least an ultrasonic vibrator, a slip ring, a motor speed reducer, a motor and an encoder, and an ultrasonic vibrator provided in the ultrasonic scanning unit. The ultrasonic endoscope according to claim 1, wherein a mechanism for correcting the distal end hard portion in a predetermined direction is provided.