JPH01221134A - Curving device for endoscope - Google Patents

Abstract

PURPOSE:To make it possible to insert the inserting part of an endoscope into a complicated shape canal to be inspected with no strong pressing force being applied to the wall surface of the canal, by computing signals obtained from position detecting elements, in a computing section, by delivering distance signals to a curve control means so as to drive a drive means for an insertion part curving means so that the insertion part is held away from the wall surface of the canal by a predetermined distance. CONSTITUTION:Infrared light radiated from LEDs 7, 7 in an insertion section 1 and reflected by the wall surface of a canal is received by position detecting elements 10 grouped with the LEDs 7. The reflected light is converted into electrical signals which are amplified by amplifiers 12, 12 and are delivered to a distance computing circuit 13 through a signal processing circuit 11 so as to compute the distance between the position detecting elements 10 and the wall surface of the canal at two positions. A distance signal is delivered to a control circuit 14 for the insertion part curving means. The control circuit 14 controls the insertion part curving means so as to make the two distance signals obtained by the position detecting elements 10, 10 equal to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscope bending device used for medical and industrial purposes.

[Prior Art] As is well known, in endoscopes used in medical treatment, the insertion section is inserted through the oral cavity or anus, and an image guide fiber or CCD (fixed imaging cord) built into the insertion section is used to navigate inside the body cavity. The patient is observed using an image transmission means, and depending on the results, a treatment instrument is inserted into the insertion section to perform treatment. Furthermore, in industrial applications, an insertion section is inserted into a site that cannot be visually observed, for example, into a tube, and an image transmission means similar to that used in medical treatment is used to determine the condition inside the tube.

[Problems to be Solved by the Invention] By the way, when using such an endoscope, there are problems regarding insertion of the insertion section, particularly in the medical field.

That is, for example, the large intestine has a complicated shape. For this reason,
Inserting an endoscope into the large intestine for diagnostic purposes requires a certain degree of skill for the endoscope operator, but due to the complex shape of the large intestine, the tip of the insertion tube presses against the wall of the large intestine. It can cause considerable pain to the patient.

This is because the means for bending the endoscope according to the will of the endoscope operator is provided only at the distal end of the insertion section.
Due to its structure, it is impossible to reduce the force exerted on the intestinal wall during insertion.

Regarding this, a method disclosed in Japanese Patent Publication No. 61-55095 has been proposed, but it cannot be applied to complex-shaped conduits such as the large intestine.

That is, in Japanese Patent Publication No. 61-55095, an observation window for the sensor is provided in the insertion part, and the end faces of the optical fiber bundle for light output and the optical fiber bundle for light input are lined up inside the observation window through lenses, respectively. The distance to the wall and the orientation can be determined by reflecting the output light from the east end of the optical fiber for light output onto the wall surface of the object to be inspected, and by detecting changes in the position of the reflected light entering the east end of the optical fiber for light input. What has been made known is disclosed.

The wall surface is observed at an appropriate position while measuring the distance to the wall surface, but a structure in which the distance can be determined only by changes in the light input position with respect to the east end surface of the light input optical fiber is difficult to achieve in a pipe with a simple shape. However, if the wall inside the tube is sloped or meandering, the light may enter at a different position than the center of the end face of the optical fiber bundle. , the endoscope cannot be guided to the center correctly.

The present invention was made in view of these circumstances, and provides an endoscope bending device that allows the insertion portion to be inserted into a complex-shaped lumen without applying strong pressing force to the wall surface. The purpose is to

[Means for solving the problem of communication] In order to achieve the above object, a plurality of infrared light irradiation means are provided along the circumferential direction at least on the outer periphery of the distal end of the insertion section of the endoscope, and the infrared light irradiation means and A pair of position detection elements that receive reflected light from the infrared light irradiation means are provided in the insertion portion. Then, an arithmetic processing section is provided which processes the signal from the position detection element to measure the distance between the insertion section and the wall surface of the lumen to be inspected based on triangulation, and at least an insertion section bending means is provided in the insertion section. and a curvature control means for controlling the driving means of the insertion section curving means in response to a signal from the arithmetic processing section, so that the insertion section is inserted into the center of the wall surface of the lumen to be inspected.

[Function] The signal obtained by the position detection element is calculated based on triangulation in the arithmetic processing section, and the obtained distance signal is input to the curvature control means, and the driving means of the insertion section curving means is controlled by the insertion section. It is driven so as to maintain a constant distance from the wall of the lumen to be inspected, so that the tip of the insertion portion does not press against the wall of the lumen.

[Example] The present invention will be described below based on a first example shown in FIGS. 1 to 5. FIG. 1 shows a bending device of an endoscope, and 1 is an insertion section of the endoscope.

The insertion section 1 is made of a bendable material, and an objective lens and a light projecting lens (both not shown) are provided at the distal end. And an image guide fiber for the objective lens.

An image transmission means 2 such as a CCD (solid-state image pickup device) is optically coupled, and an illumination light transmission means 3 such as a light guide fiber is connected to the projection lens to enable observation.

That is, the other end of the image guide fiber is optically coupled to an eyepiece (none of which is shown) of an eyepiece provided in the operating section at the proximal end of the insertion section, and the CC
At D, the signal transmission cable connected to the COD is connected to an external display device so that the observed image can be displayed on the display. The light guide fiber is connected to the end of a light guide cable (none of which is shown) that can be freely connected to the light source device, so that the illumination light from the light source device can be transmitted to the projection lens and illuminate the target area. I have to.

An insertion section bending means 4 is provided on the distal end side of the insertion section 1 of such an endoscope. The insertion portion bending means 4 includes a third
As shown in the figure, for example, a wire made of a shape memory alloy processed into a coil shape is used, and it has the ability to shrink when heated (due to the shape memory effect). These wire rods are housed in pairs (two wires) along the axial direction, for example, in opposing portions on the outer peripheral side of the distal end of the insertion portion 1. Further, each wire rod has both ends fixed to the parts constituting the insertion portion 1 so that the central portion is free, and the insertion portion 1 can be bent and displaced by contraction of the wire rod. These two wires are connected to a power supply section 6 (corresponding to a driving means) built into an endoscope bending unit 5 provided outside the endoscope, and each wire is energized from the power supply section 6. This allows the distal end side of the insertion portion 1 to be bent in the vertical (or horizontal) direction due to contraction of the wire. An insertion section bending means control circuit 14 (corresponding to a bending control means) is connected to each of these power supply units 6.degree.6.

Further, on the distal end side of the insertion section 1, for example, an insertion section bending means 4.
LEDs 7 (corresponding to infrared light irradiation means) for irradiating infrared light are provided on outer surface portions lined up with 4 in the circumferential direction, respectively. In detail, each LED 7.7
The irradiation section is arranged inside a light projecting lens 7a (only shown in FIG. 2) provided on the outer surface of the light emitting device. And this LE
An LED drive circuit 8 (shown only in FIG. 2) provided together with D7 is connected to the endoscope curvature outside the endoscope and an LED drive power source 9 built into the unit 5, and the LED drive power source 9 drives the LED 7. By energizing, infrared light can be emitted from the LED 7 toward the side of the insertion section 1.

A position detection element (PSD) 10 made of a semiconductor and paired with these LEDs 7 is provided at a position where it can receive the reflected light from the LEDs 7. In this embodiment, for example, a position detection element 10 is provided on the outer surface between the LED 7 and the insertion portion bending means 4, together with a light receiving lens 10a. Note that the insertion portion bending means 41 position detection element 10. Although the three LEDs 7 are arranged side by side, the dominant one may be arranged along the axial direction of the insertion section 1.

Using these position detection elements 10.10, it is possible to optically measure the distance between the insertion section 1 and the inner wall surface of the tube. That is, two signal processing circuits 11.11 built in the endoscope bending unit 5 are connected to each position detection element 10 via an amplifier 12.12, and the two signal processing circuits 11.11 that are output from the position detection element 10 are It is possible to process two signals. A distance calculation circuit 13 is connected to these two signal processing circuits 11 and 11, and calculates the distance between the insertion section 1 and the wall surface inside the tube based on the principle of triangulation (calculation processing section ). in particular,
As shown in the measurement principle diagram shown in FIG.
The distance calculation circuit 13 derives the distance to the object to be measured based on the light condensing position.

The distance calculation circuit 13 of such a measurement system is connected to the insertion portion bending means control circuit 14 for each system. and,
The insertion section curvature control means control concave passage 14 is defined to control energization of the insertion section curvature means 4, 4 so that, for example, distance signals obtained by the position detection elements 10.10 are all equal, and The distal end of the insertion section 1 is positioned in the center with respect to the wall surface.

The endoscope bending unit 5 and the endoscope are connected, for example, by a connector (not shown) provided on the endoscope, and are connected to an LED drive circuit 8 and an LED drive power source 9, respectively. There is.

Therefore, when inserting the endoscope configured in this way into a tube, if the tip of the insertion section 1 is inserted into the tube while the infrared light is being irradiated from the LEDs 7 and 7, the insertion section 1 The tip of the is controlled by the distance calculation circuit 13,
The insertion section 1 is inserted without pressing the wall surface inside the tube with the tip.

That is, to explain the movement of the distal end of the insertion section 1, the infrared light emitted from each LED 7 hits the wall surface inside the tube and is reflected, and the reflected light is reflected by each LED.
The light is received by the position detection element 10 that is paired with D7. Then, the reflected light is converted into an electrical signal, and then the amplifier 12
．． It is amplified by 12. Then, the amplified electrical signal is
They are output to the distance calculation circuit 13 via the signal processing circuits 11 and 11, and by applying the principle of triangulation based on the focal position, the two positions between each position detection element 10 and the wall inside the pipe are detected. The distance is calculated. These distance signals are each outputted to the insertion section bending means control circuit 14.

Then, the insertion section bending means control circuit 14 controls the insertion section bending means so that the two distance signals obtained by the position detection elements 10.10 are equal.

Specifically, when the insertion section 1 is inserted, for example, as shown in FIG.
If the distances A and B between 0 and the inner wall surface of the pipe are different (A≠B),
Under the control of the insertion portion bending means control circuit 14, the wire of the shape memory alloy on the larger distance rAJ side is energized in accordance with the distance difference.

As a result, the wire rod contracts, and the distal end of the insertion section 1 is curved so that the distance between each position detection element 10.10 and the wall surface inside the tube becomes equal as shown in FIG. 5 (C-D).
, the tip of the insertion section 1 is directed toward the center of the tube.

However, due to the structure in which the plurality of sets of position detection elements 10.10 make the insertion portion 1 the same distance from the wall surface inside the tube,
No matter what shape the lumen has, the tip can always be guided to the center of the tube, and the tip of the insertion section 1 will no longer hit the wall of the tube and press it hard.

Therefore, the endoscope operator can insert the endoscope into a complicated tube, such as the large intestine, by simply pushing the insertion section 1 of the endoscope.

Therefore, the operator of the endoscope does not need any special skills, can easily perform endoscopy, and can significantly reduce the pain caused to the patient during insertion.

Note that this invention is not limited to the first embodiment described above, but also includes the sixth embodiment.
The second embodiment shown in the figure and the third embodiment shown in FIGS. 7 and 8 may be used.

That is, in the second embodiment, two sets of insertion portion bending means 4.
A plurality of sets of curved systems composed of the LED 7 and the position detection element 10 are provided not only on the distal end side of the insertion section 1 but also along the axial direction of the insertion section 1.

In all of these structures, the distance from the position detection element 10 to the wall surface inside the tube is controlled equally by the insertion section bending means control circuit 14, as in the first embodiment, so that the bending occurs as shown in FIG. The inserted tube is inserted while the insertion portion 1 is curved according to its shape.

In the third embodiment, the curved system described in the second embodiment is applied to a side-viewing endoscope in which the objective lens 20° of the observation means and the projection lens 21 of the illumination means are provided on the side surface of the insertion section 1. It has been established.

Specifically, in a side-viewing endoscope, the objective lens 2 of the observation means
An image suitable for observation cannot be obtained unless the 0 is kept at a certain distance from the wall inside the tube. Therefore, in the above-mentioned embodiment, the distances between all the pairs of position detection elements and the inner wall surface of the pipe were made equal;
In a side-viewing endoscope, for the set of position detection elements located at the distal end, the distance between the position detection elements and the inner wall surface of the tube in the same direction as the objective lens 20 is controlled to a distance that allows observation with the objective lens 20. The distance between the other pairs of position detection elements is maintained at a constant distance as in the above-mentioned embodiment.

Such a structure that controls the distance between the objective lens 20 and the tube wall to maintain a constant distance always provides a good image in a side-viewing endoscope.

[Effects of the Invention] As explained above, according to the present invention, the distal end of the insertion section is curved so as to maintain a certain distance from the wall of the lumen to be inspected, so even if it is a complex tube such as the large intestine, Also for
Insertion can now be performed simply by pushing.

Therefore, the endoscope operator does not need any special skills at all, making endoscopy easy. Furthermore, since the insertion section can be inserted into a complex-shaped lumen without exerting a strong pressing force on the wall surface, the pain caused to the patient during insertion can be considerably reduced.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the invention,
Figure 1 is a circuit configuration diagram showing the circuit around the position detection element of the bending device, which is the main part, Figure 2 is a circuit diagram showing its optical measurement principle, and Figure 3 is a side view showing the bending device together with the insertion section. Figure 4 is a side view showing the state in which the insertion section is initially inserted into the lumen, and Figure 5 shows the state in which the insertion section has been curved to maintain a constant distance between the insertion section and the tube wall. Side view shown, No. 6
The figure is a side view showing the main parts of the second embodiment of the present invention.
The figure is a perspective view showing the main parts of the third embodiment of the present invention.
The figure is a side view thereof. DESCRIPTION OF SYMBOLS 1... Insertion part, 4... Insertion part bending means, 6... Power supply part (driving means), 10... Position detection element, 11...
・Signal processing concave path, 12... Distance calculation circuit, 14...
Insertion section curvature control circuit (curvature control means). Applicant's representative Patent attorney Atsushi Tsuboi 3rd day, 5th [] , Relationship with the case of the person making the amendment Patent applicant (037) Olympus Optical Industry Co., Ltd. 4, Agent UBE Building 7, 3-7-2 Kasumigaseki, Chiyoda-ku, Tokyo;
Contents of correction (1) "(Fixed image sensor)" in the 9th line of page 2 of the specification is corrected to "(Solid-state image sensor)." (2) Change “connect” on page 6, line 10 of the specification to “
"Connect," he corrected.

Claims (1)

[Claims] A plurality of infrared light irradiation means for irradiating infrared light toward the outside are provided along the circumferential direction on the outer periphery of at least the distal end of the insertion section of the endoscope, and at least the insertion section is paired with the infrared light irradiation means. a position detection element that is provided on the outer periphery of the distal end side and receives reflected light from the infrared light irradiation means that is reflected from the wall surface of the lumen to be inspected; an arithmetic processing unit that measures the distance to the wall surface of the lumen based on triangulation; an insertion section curving means provided at least on the distal end side of the insertion section for curving the insertion section; and the insertion section curving means. and a curvature control means that receives a signal from the arithmetic processing section and controls the drive means so that the insertion section maintains a constant distance from the wall surface of the lumen to be inspected. Characteristic endoscope bending device.