JP3119147B2 - Ultrasound diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus which is inserted into a body cavity to acquire information on a tomographic tissue in a body.

[0002]

2. Description of the Related Art An ultrasonic diagnostic apparatus to be inserted into a body has an operation section provided with an insertion section having a small diameter, and an ultrasonic transducer is provided at the tip of the insertion section. The insertion portion is inserted into the patient's body, and guides the tip end thereof to a predetermined ultrasonic inspection target portion, activates the ultrasonic vibrator, and performs ultrasonic scanning over a predetermined range. . Here, ultrasonic scanning includes linear scanning in which scanning is performed in a linear direction, radial scanning and sector scanning in which scanning is performed in a rotating direction, and a method in which mechanical scanning in which ultrasonic transducers are mechanically moved is performed. There is also an electronic scanning type in which ultrasonic transducers are arranged in a predetermined direction and these are sequentially operated.

When performing mechanical scanning in the rotation direction, an ultrasonic vibrator disposed at the distal end of the insertion section is mounted on a rotating member, and the rotating member is driven to rotate. The rotating shaft is driven to rotate by a rotation driving means such as a motor.However, since the rotation driving means cannot be provided in the insertion section which needs to be reduced in diameter, the rotation driving means is provided in the operating section, and Flexible rotation transmitting means is interposed between the rotating member and the rotating member. As the rotation transmitting means, a flexible shaft, for example, a metal wire wound in a tight coil shape is suitably used. here,
In an ultrasonic diagnostic apparatus that performs mechanical scanning in the direction of rotation, the rotational axis of the ultrasonic transducer is usually in the axial direction of the insertion section, and therefore, as an ultrasonic scanning surface, It becomes a plane orthogonal to this.

By the way, there is an ultrasonic endoscope in which an ultrasonic diagnostic apparatus and an endoscope are combined. In this ultrasonic endoscope, the observation field of the endoscope is directed forward of the insertion section. Therefore, if the scanning plane of the ultrasonic transducer is in a direction orthogonal to the axis of the insertion section, ultrasonic observation of a part in the field of view of the endoscope cannot be performed. When the affected part is found as a result of the diagnosis using ultrasonic waves, a treatment such as injecting an injection solution or performing suction is performed by inserting a puncture treatment tool into the body. In this case, it is necessary to confirm the position of the puncture device in the body by ultrasonic observation. However, if the scanning surface of the ultrasonic transducer is in a direction perpendicular to the axis of the insertion section, the puncture treatment tool must also be led out in a direction perpendicular to the axis of the insertion section. In order to insert the puncture device into the body, at least a certain length of the distal end portion of the puncture device needs to have rigidity. Therefore, the puncture device is led out so as to be sharply bent near the distal end of the insertion portion. It is extremely difficult.

In consideration of the above points, when scanning the ultrasonic transducer in the rotational direction, the rotational axis is set to a direction substantially orthogonal to the axis of the insertion portion, so that the ultrasonic scanning by the ultrasonic transducer is performed. One in which the surface is made substantially coincident with the axial direction of the insertion portion is disclosed in, for example, Japanese Utility Model Publication No. 7-30010. In this known ultrasonic diagnostic apparatus,
A rotating shaft is provided at one end of a rotating member to which the ultrasonic vibrator is attached, and a flexible shaft is connected to the rotating shaft,
The direction of the flexible shaft is changed by bending the flexible shaft by approximately 90 ° so as to be in the axial direction of the insertion portion. 90 ° flexible shaft consisting of close-coil
Even if the direction is changed, it is possible to transmit the rotation.
Then, in order to suppress the flexible shaft from vibrating at the direction changing portion, a part of the direction changing portion is inserted into a hard pipe.

[0006]

In order to perform ultrasonic diagnosis with the ultrasonic diagnostic apparatus having the above configuration, the ultrasonic vibrator is rotated, and the ultrasonic vibrator is directed toward the body at a predetermined angle during the rotation. Transmit the sound pulse and receive the reflected echo. The reflected echo signal is transmitted to the ultrasonic observation apparatus, and the signal processing unit of the ultrasonic observation apparatus performs signal processing. The signal processing unit has a scan converter, and a reflected echo signal for each predetermined angle is taken into the memory of the scan converter. When the ultrasonic vibrator makes one rotation, an ultrasonic image signal for one frame is stored in the memory. . Therefore, the ultrasonic image signal generated each time the ultrasonic transducer makes one rotation is read from the scan converter memory, and the ultrasonic image is displayed on the monitor. The ultrasonic image displayed on the monitor includes a radial ultrasonic image having a scanning range of 360 ° or a sector-shaped sector ultrasonic image in which the scanning range is limited to a predetermined angle range.

[0007] Regardless of whether a radial ultrasonic image is displayed or a sector ultrasonic image is displayed, when performing ultrasonic scanning, the angular position of the ultrasonic transducer must be detected. Further, it is necessary to set not only the relative angular position of the ultrasonic transducer but also the scanning origin position. And
An ultrasonic image for one frame is generated from the ultrasonic reflected echo signals acquired over a range of 360 ° from the scanning origin position (in the case of radial scanning) or a predetermined angle range (in the case of sector scanning) from the scanning origin position. You.

In order to detect the angular position of the ultrasonic transducer and the position of the scanning origin, the ultrasonic diagnostic apparatus is provided with a rotation angle detecting means. As the rotation angle detecting means, a rotary encoder is used. Used. Here, there are absolute encoders and incremental encoders as encoders.If an absolute encoder is used, the absolute position of the ultrasonic vibrator can be detected.If an incremental encoder is used, the absolute position of the ultrasonic vibrator is Although this type of encoder cannot be detected, this type of encoder has a reference position, and therefore, it is sufficient to match this reference position with the scanning origin position. In many cases, small incremental encoders with excellent angular resolution are used.However, regardless of which type of encoder is used, it is necessary to place this encoder at the tip of the insertion section and directly detect the rotation angle of the ultrasonic transducer. For example, the rotation angle of the ultrasonic transducer can be accurately detected.However, in order to reduce the diameter of the insertion section inserted into the body cavity, an encoder is arranged at the tip of the insertion section provided with the ultrasonic transducer. It cannot be set up. Therefore,
The rotation angle of the base end of the flexible shaft that rotationally drives the ultrasonic transducer is detected, and the rotation angle of the ultrasonic transducer is estimated based on the detection signal.

As described above, the flexible shaft is made of a close-coil coil. Therefore, even when the flexible shaft is bent to some extent, it is possible to accurately transmit the rotational force from the base end to the tip. However, when the flexible shaft composed of the close contact coil starts to be driven to rotate on the base end side, a slight delay occurs when the rotational force is transmitted to the distal end by the action of a load such as sliding resistance. In particular, when the flexible shaft is bent, the degree of transmission delay of the rotational force increases. However,
After the rotational force reaches the distal end, the rotational force is transmitted accurately unless the load fluctuates by bending the flexible shaft or the like. Therefore, in the rated rotation state, the flexible shaft rotates while maintaining the state in which the phase is shifted by the amount corresponding to the rotation transmission delay between the base end and the distal end.

In particular, when the rotation axis of the ultrasonic transducer is in a direction substantially orthogonal to the axis of the insertion portion as in the above-described prior art, the flexible shaft is bent 90 ° in the middle. Therefore, the transmission delay of the rotation becomes considerably large. And the flexible shaft is 90
° Immediately after being bent, it passes through the angle part, and this angle part is bent, and depending on the degree of this bending operation, the flexible shaft is bent complicatedly, and sliding resistance etc. Is significantly increased, and the transmission delay of rotation becomes remarkable.

When the rotation of the base end of the flexible shaft is detected, the reference position of the encoder is used as the scanning origin position of the ultrasonic image displayed on the monitor. If the deviation becomes remarkable, the phase between the actual position in the body and the position on the ultrasonic image is shifted when performing the radial scanning and the sector scanning. When such a phase shift occurs, it is not only undeniable that a discomfort occurs when performing ultrasonic observation,
There is a mismatch between the data created on the ultrasound observation device side and the ultrasound image data. For example, when the puncture treatment tool is inserted into the body, a puncture line serving as an index is displayed on the ultrasonic image. The puncture line generates a character signal on the ultrasonic observation apparatus side based on the scanning origin position and the opening position and direction of the lead-out section of the puncture treatment tool. If there is a phase shift between the position and the position, the puncture line indicates a direction different from the actual insertion direction of the puncture treatment tool by the amount of the phase shift.

The present invention has been made in view of the above points, and an object of the present invention is to provide a rotation angle detecting means provided at a base end of a flexible shaft. An object of the present invention is to enable a rotation angle of a sound wave transducer to be accurately detected.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, according to the present invention, a flexible shaft composed of a close-contact coil is connected to both sides of a rotating member equipped with an ultrasonic vibrator. A rotation transmission means that changes its direction from a direction substantially orthogonal to the axis of the insertion portion to the axial direction and is taken out of the insertion portion, and is connected to the end of one of the two flexible shafts. Rotation driving means, rotation angle detection means connected to ends of both flexible shafts, and detection signals of both rotation angle detection means are taken in, and the ultrasonic wave is detected based on a difference between the detection signals of both rotation angle detection means. It is characterized by comprising a rotation delay detecting means for detecting a rotation delay of the vibrator.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In order to scan an ultrasonic vibrator in a rotating direction, the ultrasonic vibrator is mounted on a rotating member, and the rotation axis of the rotating member is directed in a direction substantially orthogonal to the axis of the insertion portion. . As a result, the scanning surface of the ultrasonic transducer is oriented in the axial direction of the insertion section, and when configured as an ultrasonic endoscope, the position of the center or near the center of the endoscope observation field of view is measured by ultrasonic observation. It can be a field of view, and when using a puncture device, the state of insertion into the body can be put into the ultrasonic observation field even if the puncture device is led out in the axial direction of the insertion portion. become. The rotating shaft extends on both sides of the ultrasonic transducer, and a flexible shaft is connected to each end. These two flexible shafts are turned around 90 ° from the connection to the rotating shaft, extend in the axial direction of the insertion portion, and are taken out of the insertion portion. Then, these two flexible shafts are inserted through the insertion section into the operation section or into a cable drawn from the operation section, and extend to the ultrasonic observation apparatus.

FIG. 1 shows the basic structure of the ultrasonic transducer and its rotation drive mechanism. In FIG. 1, reference numeral 1 denotes an ultrasonic vibrator, which is mounted on a rotating member 2 and performs ultrasonic scanning by rotating the rotating member 2 about its rotation axis A. It has been made like that. In order to rotate and drive the ultrasonic vibrator 1 by remote control, a flexible shaft 3 composed of a close contact coil is used. The flexible shaft 3 is connected to a rotation shaft 4 at a base end side, and is driven by the rotation shaft 4. Gear 5 is attached. The driven gear 5 is meshed with a drive gear 7 connected to a rotating shaft of a motor 6. The flexible shaft 3 is connected to one side of the rotating member 2, and another flexible shaft 8 is connected to the other side. The flexible shaft 3 is a driving-side flexible shaft that is driven to rotate around an axis by a motor 6, whereas another flexible shaft 8 is provided.
Is not connected to the driving means, and serves as a driven-side flexible shaft to which rotation from the driving-side flexible shaft 3 is transmitted via the rotating member 2.

These two flexible shafts 3, 8
Are of the same structure with the same wire diameter and outer diameter, and have the same length. And these two flexible shafts 3, 8
Are rotated by approximately 90 ° and are arranged so as to be line-symmetric with respect to a center line N-N in a direction orthogonal to the rotation axis A of the rotation member 2. And the driven-side flexible shaft 8
A rotary shaft 9 is also connected to a base end of the rotary shaft 4. A driven gear 5 provided on the rotary shaft 4 of the drive-side flexible shaft 3 has an input attached to an input shaft of a rotary encoder 10 as a rotation angle detecting means. Gear 11 is meshed with the transmission gear 12 and the transmission gear 12 is also attached to the rotating shaft 9.
The input gear 14 of another encoder 13 is also meshed with 2.

In the above arrangement, the ultrasonic transducer 1 is rotationally driven by rotating the drive-side flexible shaft 3 of the two flexible shafts with the motor 6. In this manner, by rotating the driving-side flexible shaft 3, the rotating member 2 rotates around its rotation axis A. However, the drive-side flexible shaft 3 is turned 90 ° in the vicinity of the distal end, and when the drive-side flexible shaft 3 rotates, various loads such as sliding resistance act on the drive-side flexible shaft 3, so that a delay in rotation transmission occurs. . Since the encoder 10 is connected to the base end of the drive-side flexible shaft 3, a deviation occurs between the reference position of the encoder 10 and the scanning origin position of the ultrasonic transducer 1.

Since the driven side flexible shaft 8 is connected to the rotating member 2, the rotating member 2
Following the rotation, the driven-side flexible shaft 8 also rotates around the axis. The transmission of the rotational force also has a delay from the connection of the driven flexible shaft 8 to the rotating member 2 to the base end to which the encoder 13 is connected. In addition, since the driven flexible shaft 8 has the same structure and the same load acting upon its rotation as the drive flexible shaft 3, the condition of the rotation delay is substantially equal to the rotation delay of the drive flexible shaft. Be the same. Therefore, the detection angle of the encoder 13 has a delay with respect to the detection angle of the encoder 10, and this delay is substantially twice the rotation delay of the rotating member 2.

As described above, the function of detecting the rotation angle of the ultrasonic vibrator 1 is provided to the encoder 10 on the drive-side flexible shaft 3 side, and half of the delay in the detection signal between the encoders 10 and 13 is reduced by the rotation delay. By detecting this by the detection means and correcting the delay with respect to the detection angle signal of the encoder 10, even if a load is applied to the rotation of the drive-side flexible shaft 3, the ultrasonic vibrator is almost accurately 1 can be detected. Therefore, the reference position of the encoder 10 and the scanning origin position of the ultrasonic transducer 1 can be accurately matched. When the encoder 13 of the driven-side flexible shaft 8 is used to detect the rotation angle of the ultrasonic vibrator 1, it suffices to have a half of the difference in the detection signal between the encoders 10 and 13.

In addition, during the ultrasonic observation, if the load fluctuates due to, for example, bending the angle portion, the transmission delay amount of the rotational force changes accordingly. However, when the rotation angle of the driven flexible shaft 3 is detected by the encoder 10, the rotation angle of the driven flexible shaft 8 is always detected by the encoder 13 and the correction is performed. During the operation of 1, the reference position of the encoder 10 and the scanning origin position of the ultrasonic transducer 1 do not shift.

As described above, if the drive-side flexible shaft and the driven-side flexible shaft are under exactly the same conditions, the ultrasonic vibrator rotates with a rotation delay of half the rotation delay at both ends. As long as the condition that a certain relation is established for the rotation delay between the driving-side flexible shaft and the driven-side flexible shaft is satisfied, it is not always necessary to make both flexible shafts the same condition, and the rotation delay depends on the degree of the rotation delay. What is necessary is just to make it have a correction coefficient.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings. Note that, in the following description, a configuration configured as an ultrasonic endoscope will be described.
The present invention is not limited to this, and may not include an endoscope observation mechanism.

First, FIG. 2 shows the overall configuration of the ultrasonic endoscope. In the figure, 20 is an ultrasonic endoscope main body, 21 is an endoscope observation device unit, and 22 is an ultrasonic observation device unit. The ultrasonic endoscope 20 includes an insertion portion 23 inserted into a body cavity, a main body operation portion 24 connected to a base end of the insertion portion 23, and a universal cord 25 pulled out from the main body operation portion 24. Be composed. Insertion part 23
Is a flexible portion 23a that bends in an arbitrary direction following the insertion path for most of the length from the side of the portion connected to the main body operation portion 24, and the distal end of the flexible portion 23a has an angle A portion 23b and a tip body 23c are sequentially provided at the tip of the angle portion 23b. The distal end body 23c is provided with an endoscope observation mechanism and an ultrasonic observation mechanism, which will be described later.
In order to turn c in an arbitrary direction, an angle operation is possible.

The distal end of the universal cord 25 is branched into three, one of which is detachably connected to the light source section of the light source / processor section 21a constituting the endoscope observation device unit 21. The light source connector 25a is provided. Another one is a light source / processor unit 21a.
And an electrical connector 25b detachably connected to the processor unit of the ultrasonic observation apparatus unit 22, and an ultrasonic connector 25c detachably connected to the signal processing unit 22a of the ultrasonic observation apparatus unit 22. . Then, the endoscope observation device unit 21 and the ultrasonic observation device unit 22
Has monitors 21b and 22b for displaying an endoscope image and an ultrasonic image.

FIGS. 3 and 4 show the distal end surface of the distal end body 23c and its cross section. As is apparent from FIG. 3, an endoscope observation mechanism is provided on an upper side of the distal end surface of the distal end portion main body 23c, and an ultrasonic observation mechanism is provided on a lower side thereof.

The endoscope observation mechanism is provided with an illumination window 26 for irradiating illumination light toward the inside of the body and an observation window 27 for observing the inside of the body under this illumination. A light guide faces the illumination lens. An objective lens is mounted on the observation window 27, and the incident end of the solid-state imaging device or the image guide faces the image forming position of the objective lens. Further, in addition to the illumination window 26 and the observation window 27, a treatment tool deriving unit 28 for deriving the treatment tool is provided.

Reference numeral 30 denotes an ultrasonic observation mechanism. The ultrasonic observation mechanism 30 has a housing 31 projecting forward from the distal end main body 23c, and an ultrasonic vibrator 32 is provided in the housing 31. The ultrasonic vibrator 32 is mounted on a rotating member 33. Rotating member 3
3 has rotating shafts 33a and 33b at both ends thereof, and these rotating shafts 33a and 33b extend in a direction substantially orthogonal to the axis of the insertion portion 23, and partition the interior of the housing 31 into three chambers 31a to 31c. The partition walls 34a and 34b to be formed are rotatably mounted via bearings 35. Partition wall 34
The ultrasonic vibrator 32 is disposed in a chamber 31b between a and b, and the chamber 31b becomes a closed ultrasonic vibrator storage room. And at least the chamber 31b
The inside is filled with an ultrasonic transmission medium such as liquid paraffin in order to transmit and receive ultrasonic signals by the ultrasonic transducer 32 without loss. Therefore, the portion of the chamber 31b in the housing 31 is
Function as

Chambers 31 on both sides in housing 31
a, a rotating shaft 33a, 33b extending into the inside 31c, a flexible shaft 37 constituting a rotation transmitting means.
a and 37b are connected to each other. The flexible shafts 37a and 37b are respectively provided in the chamber 3
1a and 31c, the direction is changed by approximately 90 °, and the insertion portion 23
In the axial direction. Insertion passages 38a, 38b are formed in the distal end body 23c, and the flexible shafts 37a, 37b are connected to the insertion passages 38a, 38b.
38b. Flexible shaft 37
Reference numerals a and 37b denote an end portion main body 23c of the insertion portion 23, an angle portion 23b and a flexible portion 23a connected thereto.
, And extends into the main body operation section 24, but is inserted through the flexible sleeves 39a and 39b in the angle section 23b and the soft section 23a. In addition,
40a and 40b are connection pipes for connecting the flexible sleeves 39a and 39b to the insertion passages 38a and 38b.

The flexible shafts 37a and 37b are
It is formed by winding a metal wire in the form of a contact coil. When rotating in only one direction, it may be formed with a single contact coil. On the contrary, it can be provided in multiple layers, formed in multiple strips by winding a plurality of metal wires at the same time, or can be formed in multiple strips. Here, since the flexible shafts 37a and 37b scan in the rotation direction, and there is no need to change the rotation direction, the flexible shafts 37a and 37b are formed by a single contact coil to reduce the diameter of the flexible shafts 37a and 37b. Is preferred.

Since signals are transmitted and received to the ultrasonic transducer 32, two signal transmission paths, ie, a path for transmitting a drive signal and a path for transmitting an ultrasonic reception signal, are connected. The transmission path is the ultrasonic observation device unit 22
To the signal processing unit 22a. The flexible shafts 37a and 37b are hollow members, and the signal cable 41a for the drive signal and the signal cable 41b for transmitting the ultrasonic reception signal are respectively connected to the flexible shaft 3a.
7a and 37b. The flexible shafts 37a and 37b are internally provided with the signal cable 41.
a, 41b are inserted, and a flexible sleeve 39 is provided on the outside.
5 and 6, with the a and 39b covered, they extend into the main body operation unit 24 and are mounted on the mounting plate 42. The flexible sleeves 39a and 39b are fixed to connecting pipes 43a and 43b attached to the mounting plate 42, and the flexible shafts 37a and
Reference numeral 7b is connected to rotating shafts 44a and 44b provided through the mounting plate 42 so as to be rotatable.

A motor 45 is provided on the mounting plate 42 on the side opposite to the side where the flexible shafts 37a and 37b are connected.
Is connected to a drive gear 46. Also, the rotating shaft 44
A driven gear 47a is attached to a. And
The drive gear 46 meshes with the driven gear 47a, and therefore, of the two flexible shafts 37a and 37b, the flexible shaft 37a is a drive-side flexible shaft that is driven to rotate by the motor 45. The driving force is not supplied to the other flexible shaft 37b, and the driving-side flexible shaft 37a
The transmission gear 47b is attached to the rotating shaft 44b connected to the driven flexible shaft. The driven gear 47a provided on the rotating shaft 44a meshes with the input gear 48a of the first encoder 48 in addition to the driving gear 46 described above, and the transmission gear 47b provided on the rotating shaft 44b has a second gear. Encoder 4
9, the input gear 49a is meshed.

Here, the two flexible shafts 37a and 37b have the same structure and the same length. In addition, these two flexible shafts 37a, 3
7b is arranged so as to be substantially symmetrical with respect to the axial center line of the insertion portion 23. Thereby, the rotation condition of the drive side flexible shaft 37a and the rotation condition of the driven side flexible shaft 37b become substantially the same.

The signal cables 41a and 41b are led out from the flexible shafts 37a and 37b,
They are connected to rod-like electrodes 50a, 50b inserted into 4a, 44b. Therefore, the rotating shafts 44a and 44b are formed of an electrically insulating member, or the driven gear 47a and the transmission gear 47b are formed of an electrically insulating member. And the electrode 50
a and 50b are in contact with brush electrodes 52a and 52b connected to the cables 51a and 51b. by this,
Electrodes 50a, 50 rotating with rotating shafts 44a, 44b
b and the cables 51a and 51b are electrically connected.

The ultrasonic observation mechanism 30 is configured as described above. Next, referring to FIG.
2 shows a circuit configuration of a signal processing unit 22a.

In the figure, reference numeral 53 denotes a transmission / reception circuit. The ultrasonic transmission / reception circuit 53 includes cables 51a and 51b and signal cables 41a and 41 connected to the ultrasonic vibrator 32.
b, a drive signal is supplied to the ultrasonic vibrator 32, and after supplying this drive signal, the mode is switched to the reception mode for a predetermined time and the reflected echo signal received by the ultrasonic vibrator 32 And processes the received signal of the ultrasonic reflected echo. 54 is an A / D converter, 55 is a scanning control circuit, 56 is a memory, 57 is a D / A
Converters, which enable the scan converter 58
Is configured.

The rotation angle position of the ultrasonic transducer 32 is input to the scan control circuit 55 of the scan converter 58. The rotation angle signal of the ultrasonic transducer 32 is supplied to the drive-side flexible shaft 37a. A control signal is sent to a servo circuit 59 of a motor 45 for rotationally driving the motor 45, so that the rotation speed of the drive flexible shaft 37a by the motor 45 is controlled to be constant. Further, based on the rotation angle position signal of the ultrasonic transducer 32,
The switching of the transmission / reception mode of the ultrasonic transmission / reception circuit 53 is performed, and further, the signal is stored in the memory 56 as a signal related to the position of the ultrasonic image displayed on the monitor 22b.
It is also taken in.

As described above, the rotation angle of the ultrasonic vibrator 32 is detected primarily by the first encoder 48 for detecting the rotation of the drive-side flexible shaft 37a.
It is. The supply of the control signal to the servo circuit 59 and the switching control signal to the ultrasonic transmission / reception circuit 53 are as follows:
This is performed only with the detection signal from the first encoder 48.
As the position signal of the ultrasonic image data in the memory 56 of the scan converter 58, not only the angle signal of the ultrasonic transducer 32 but also the scanning origin signal is required. Since the drive-side flexible shaft 37a is made of a close-contact coil, the base end portion, that is, the connection portion to the first encoder 48, and the front end portion, that is, the ultrasonic vibrator 32
A phase shift occurs between the connection portion and the connection portion. Therefore, a rotation delay detection / correction circuit 6 for correcting the phase shift is provided.
0 is provided.

The rotation delay detection / correction circuit 60 calculates the difference between the first encoder 48 connected to the driving side flexible shaft 37a and the second encoder 48 connected to the driven side flexible shaft 37b. The half of the difference is taken as the rotation delay at the tip end of the first flexible shaft 37a, and a signal obtained by correcting the rotation delay in the output signal of the first encoder 48 is loaded into the memory 56. Thus, regardless of the state of the insertion portion 23, the drive-side flexible shaft 37a
, The phase shift at both ends is corrected, and an accurate ultrasonic image can be displayed.

Now, both flexible shafts 37a, 37
Considering b as one flexible shaft, when one end is rotated and a rotational force is transmitted to the other end, a rotation delay occurs according to the load. The ultrasonic vibrator 32 is provided at the intermediate position, and the part before and after the part where the ultrasonic vibrator 32 is provided rotates under substantially the same conditions. Therefore, the ultrasonic transducer 32 has a rotation delay of half the rotation delay generated between both ends. The rotation delay detection / correction circuit 60 calculates a difference corresponding to の of the difference between the signals of the first and second encoders 48 and 49, thereby obtaining the ultrasonic vibrator 32.
It becomes possible to detect the rotation delay of the portion provided with the sine-thickness almost accurately. In addition, since the delay is constantly corrected by the rotation delay detection / correction circuit 60, the insertion section 23 is moved while the ultrasonic scanning is being performed.
Even if the bending operation of b is performed, there is no possibility that the scanning origin position on the ultrasonic image is shifted.

The present embodiment is configured as described above. Next, a case will be described in which the ultrasonic endoscope 1 performs various inspections using an endoscope and ultrasonic waves in a patient's body. The operation will be described.

First, the insertion section 23 of the ultrasonic endoscope 20 is inserted into a body cavity of a patient, and is guided to a predetermined examination target section.
Here, an angle portion 23b is continuously provided to the distal end portion main body 23c at the distal end of the insertion portion 23, and the angle portion 23b can be bent in a desired direction by an angle operation. The distal end can be oriented in a desired direction, and an image of the inside of the body cavity by the endoscope observation mechanism 20 provided on the distal end portion main body 23c is projected on the monitor 2b of the endoscope observation device unit 21 while checking with the monitor 2b. By inserting the insertion portion 23, it is possible to easily and surely lead to the inspection target portion. Of course, the insertion path in the body cavity is bent in various directions, but the flexible portion 23a follows the insertion path and bends in any direction.

When the distal end main body 23c is guided to the portion to be inspected, the condition inside the body is inspected via the endoscope observation mechanism. What can be inspected by the endoscope observation mechanism is the state of the surface of the wall of the body cavity and the like. Therefore, when information on the body tissue is required, the ultrasonic observation mechanism 30 is operated. here,
The ultrasonic observation field of view by the ultrasonic observation mechanism 30 is the insertion section 2
3, the distal end body 23 of the insertion portion 23
By orienting c in an arbitrary direction, various visual field ranges can be obtained. For example, the pancreatic bile duct is put into the ultrasonic observation field from the inside of the stomach. Can be in range.

When a site suspected of a lesion is found based on the observation by the endoscope observation mechanism 20, for example, an ultrasonic wave is transmitted / received to / from the site, thereby obtaining an ultra-sound related to the tissue tomography in the body. The sound wave image is displayed on the monitor 3b of the ultrasonic observation device unit 22. Here, since the center of the ultrasonic observation field of view is hardly different from the center of the endoscope observation field of view, the position where the ultrasonic observation is performed is positioned at the center of the endoscope observation field of view, so that it is almost accurate. The ultrasonic observation of the necessary place can be performed.

In performing the ultrasonic observation, the drive-side flexible shaft 37a is rotationally driven by a motor 45 provided in the main body operation unit 24, and is connected to the tip of the drive-side flexible shaft 37a, so that the ultrasonic wave is transmitted. The rotating member 33 provided with the vibrator 32 is rotated. Then, every time the ultrasonic vibrator 32 rotates by a predetermined angle, an ultrasonic pulse is transmitted toward the body and a reflected echo is received. The ultrasonic reception signal is transmitted to the ultrasonic observation device 22.
Transmitted to the signal processing unit 22a of the
After the predetermined signal processing is performed in step 3, the data is stored in the memory 56 of the scan converter 58, and when the ultrasonic reception signal for one frame is stored in the memory 56, the data stored from the memory 56 is deleted. Read and monitor 22b
Is displayed as an ultrasonic image.

The drive-side flexible shaft 37a is made of a close-contact coil, and is turned by approximately 90 ° from a portion connected to the rotating member 33, so that the resistance is large when rotating, and the resistance is also obtained by bending the angle portion 23b. Is changed, and a phase difference is generated between the base end portion and the front end portion of the drive-side flexible shaft 37a, and the ultrasonic vibrator 32 driven to rotate at the front end portion has a rotation delay. However,
The rotating member 33 includes a driven flexible shaft 3 that rotates under the same rotation conditions as the driving flexible shaft 37a.
7b, the output signal from the first encoder 48 connected to the drive-side flexible shaft 37a is corrected by the output signal from the second encoder 49 provided on the driven-side flexible shaft 37b. There is no inconvenience such as a change in the scanning origin position depending on the state of the insertion section.

[0046]

As described above, according to the present invention, when a rotating member provided with an ultrasonic vibrator is driven to rotate by a flexible shaft composed of a contact coil, another flexible shaft is connected to the rotating member. Then, both of these flexible shafts are turned in the direction of the axis from a direction substantially perpendicular to the axis of the insertion portion, taken out of the insertion portion,
Since the rotation angle detecting means is connected to the ends of the two flexible shafts, and the rotation delay of the ultrasonic transducer is detected based on the difference between the detection signals of the two rotation angle detecting means, the flexible shaft is provided. The rotation angle of the ultrasonic transducer provided at the distal end of the flexible shaft can always be accurately detected by the rotation angle detection means provided at the base end of the flexible shaft, regardless of the posture and state of the insertion portion. And so on.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view of a rotation detecting mechanism of an ultrasonic transducer in an ultrasonic diagnostic apparatus of the present invention.

FIG. 2 is an overall configuration diagram of an ultrasonic endoscope as an ultrasonic diagnostic apparatus according to an embodiment of the present invention.

FIG. 3 is an external perspective view of a distal end surface of an insertion section.

FIG. 4 is a sectional view taken along line XX of FIG. 2;

FIG. 5 is an explanatory diagram of a configuration of a rotation drive mechanism of the ultrasonic transducer.

FIG. 6 is an operation explanatory view showing a state in which the puncture treatment tool is mounted on the ultrasonic endoscope.

FIG. 7 is a circuit configuration diagram of a signal processing unit of the ultrasonic observation apparatus.

[Explanation of symbols]

 1,32 Ultrasonic vibrator 2,33 Rotating member 3,37a Driving side flexible shaft 4,33a Rotating shaft 6,45 Motor 10,13 Encoder 20 Ultrasonic endoscope 22 Ultrasonic observation device unit 23 Insertion section 48 First Encoder 49 second encoder 53 ultrasonic transmission / reception circuit 58 scan converter 60 rotation delay detection / correction circuit

Claims (2)

(57) [Claims] 1. A rotary member having a rotation axis in a direction substantially orthogonal to the axis of the insertion portion is provided at a tip of the insertion portion, and an ultrasonic vibrator is attached to the rotation member and provided. In an ultrasonic diagnostic apparatus configured to scan a child in a rotational direction, flexible shafts each formed of a close-contact coil are connected to both sides of the rotating member, and these flexible shafts are connected to the axis from a direction substantially orthogonal to the axis of the insertion portion. The direction of rotation is changed, the rotation transmitting means to be taken out of the insertion portion, of these two flexible shafts, the rotation driving means connected to the end of one of the flexible shaft, the end of both flexible shafts Detection signals of the rotation angle detection means and the rotation angle detection means connected to each other are taken in, and based on a difference between the detection signals of the rotation angle detection means, An ultrasonic diagnostic apparatus comprising: a rotation delay detecting unit configured to detect a rotation delay of an ultrasonic transducer. 2. The two flexible shafts have the same length as a close contact coil having the same structure, and are arranged so as to be substantially line-symmetric with respect to the axial center line of the insertion portion. Of the two rotation angle detection means, the detection signal from one rotation angle detection means is used as the rotation angle detection signal of the ultrasonic vibrator, and the rotation angle detection signal includes the detection signal of the two rotation angle detection means. 2. The ultrasonic diagnostic apparatus according to claim 1, wherein a delay of half of the difference is set as a rotation delay of the ultrasonic transducer, and the rotation angle detection signal is corrected.