JPH0727922Y2 - Endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an endoscope in which the distal end of an insertion portion is freely bendable.

[Prior Art] In some endoscopes, the tip of the insertion portion can be electrically bent in the vertical and horizontal directions.

However, if such electrification is adopted, there is a risk of moving the tip too much and damaging the living body.

Therefore, as disclosed in, for example, Japanese Patent Laid-Open No. 61-87530, a pressure-sensitive element is provided at the tip of the insertion portion to detect contact of the tip with a living body wall by pressure detection, and the movement of the tip is restricted during detection. There is something I tried to give.

[Problems to be Solved by the Invention] However, when the pressure-sensitive element is provided as described above, it is necessary to dispose at least a pair of lead wires in the insertion portion, which causes a problem of increasing the diameter of the insertion portion. .

This invention was made in view of the above circumstances,
The purpose is to provide an endoscope that can detect contact between the tip of the insertion part and a living body without increasing the diameter of the insertion part and can prevent damage to the living body due to bending. To provide.

[Means for Solving the Problem] In an endoscope in which a tip of an insertion portion is bendable, a first electrode provided at a tip of the insertion portion, a second electrode capable of contacting a body surface, and a first electrode , A detection unit which is formed by coating one of the second electrodes with an electrically insulating material, and detects the contact between the tip of the insertion unit and the living body wall based on the change in the capacitance between the electrodes, and the detection unit. When the contact is detected, means for notifying the contact or restricting the movement of the tip of the insertion portion.

[Operation] The contact between the tip of the insertion portion and the living body wall is detected from the change in the capacitance between the first electrode and the second electrode.

Since the lead wire of the first electrode passes through the inside of the insertion portion, but the lead wire of the second electrode does not pass through the inside of the insertion portion, it is possible to avoid increasing the diameter of the insertion portion.

[Embodiment] A first embodiment of the present invention will be described below with reference to the drawings.

In FIG. 3, reference numeral 1 denotes an electric endoscope, which is composed of a main body 2, an operation portion 3, an insertion portion 4, and a light cable 5. The insertion portion 4 has a distal end member 8 attached to the distal end of a flexible tube portion 6 via a bending tube portion 7.

The bending tube portion 7 is formed by connecting a plurality of short tubular joint members 9 arranged along the axial direction to each other so as to be pivotally connected to each other, and can be bent vertically and horizontally.

On the tip member 8, the exit tip 12 of the light guide 11 and the objective lens 13 are arranged. In addition, the objective lens 13
The incident tip portion 15 of the image guide 14 is arranged so as to face the.

The other end of the light guide 11 is guided into the light guide cable 5 through the insertion portion 4 and the operation portion 3, and further,
It is adapted to be connected to a light source device (not shown).

The other end of the image guide 14 has an insertion portion 4 and an operation portion 3.
It is guided through the inside to the eyepiece 16 provided on the operation unit 3,
It is arranged to face the eyepiece lens 17 in the eyepiece section 16.

On the other hand, in the operation section 3, only the bending operation mechanism 20 for remotely bending the bending tube section 7 of the insertion section 4 is shown.
However, a bending operation mechanism in the left-right direction is also provided.

That is, the bending operation mechanism 20 includes a motor 21 that can rotate in the normal and reverse directions.
Comprising a drum 22 driven by
The base ends of the pair of upper and lower operation wires 23A and 23B are wound around the outer periphery of the respective from opposite sides.

The operation wires 23A and 23B pass through the insertion portion 4 and the bending tube portion 7
And is connected to the corresponding upper and lower parts of the frontmost joint member 9 of the bending tube portion 7.

Then, when the drum 22 is rotated, one operation wire 23
A, 23B is caught and pulled, and the other operation wire 23A, 2
3B is drawn out and bent in the direction of pulling the bending tube portion 7.

In the middle of the operation wires 23A and 23B, the slack remover 24,
25 are inserted respectively.

Gears 26 and 27 are attached to the rotary shaft of the motor 21 and the rotary shaft of the drum 22, respectively, and the gears 26 and 27 mesh with each other. Therefore, the rotation of the motor 21 causes the rotation to be transmitted to the drum 22.

A first potentiometer (not shown) is connected to the transmission shaft 33 of the drum 22. This first potentiometer incorporates a sliding contactor that rotates in conjunction with the transmission shaft 33 of the drum 22. Therefore, the output voltage of the first potentiometer changes according to the rotational movement amount of the drum 22.

The operation section 3 includes a bending operation lever 30 as a bending operation member.
Is rotatably provided. This bending control lever 30
Is projected to the outside of the operation portion 3 so that the operator can rotate it back and forth by hand. That is, when the bending tube portion 7 is raised, the bending operation lever 30 is tilted rearward, when it is lowered, the bending operation lever 30 is tilted forward, and when the bending tube portion 7 is straightened, it is set to an intermediate neutral position.

The rotary shaft of the bending operation mechanism 30 has a second potentiometer.
31 are connected. The second potentiometer 31 is also constructed similarly to the first potentiometer.

That is, the second potentiometer 31 has a built-in sliding contactor that rotates in conjunction with the rotation shaft of the bending operation lever 30. Therefore, the output voltage of the second potentiometer 31 changes according to the amount of rotational movement of the bending operation lever 30.

By the way, the first and second potentiometers are connected to a drive circuit (not shown).

This drive circuit has a built-in operational amplifier that compares the voltages input from the potentiometers and outputs a signal of a voltage level corresponding to the difference, and constitutes a servo circuit. That is, the motor 21 is rotationally driven in both forward and reverse directions according to the turning direction and the turning amount of the bending operation lever 30.

In the endoscope 1 having such a configuration, as shown in FIGS. 1 and 2, a ring-shaped first electrode 41 having an outer diameter smaller than that of the tip member 8 is embedded in the tip member 8. Then, one end of the lead wire 42 is connected to the first electrode 41, the lead wire 42 is guided through the insertion portion 4 to the outside of the endoscope 1, and is connected to the detection portion 90.

The second electrode 44 is connected to the detection unit 90 via another lead wire 43.
Connect. The second electrode 44 can contact the surface (body surface) of the living body 70. Further, the display unit 60, which is a notification means, is connected to the detection unit 90.

(6) Add the following sentence between paragraph 12, line 10 and line 11 of the specification.

 Next, the operation of the above configuration will be described.

First, the second electrode 44 is brought into contact with the surface of the living body 70. Then, the insertion section 4 is inserted into the living body, and when the tip of the insertion section 4 reaches the target site, the bending operation lever 30 is operated to bend the tip. At this time, the peripheral surface of the tip member 8 is the living body 70.
When it touches the inner wall of the, it is detected.

The detection unit 90 includes a DC power supply 91, the power supply 91 and lead wires 4
Oscillation circuit 92 connected to electrodes 41 and 44 via 2, 43, comparator 93 whose output is supplied to the positive side input terminal (+), negative side input terminal of this comparator 93 ( −) To variable resistor 94
It is composed of a DC power supply 95 connected via the trigger circuit 96 and a trigger circuit 96 which issues a trigger signal when a voltage is output to the comparator 93.

That is, a capacitor is formed by the electrodes 41 and 44, and when a substance having a high dielectric constant, such as the living body 70, is present between the electrodes 41 and 44 and the electrical condition between the electrodes, that is, the capacitance changes, The oscillation circuit 92 oscillates.

When the oscillation output is generated, a voltage is generated at the output terminal of the comparator 93,
A trigger signal is issued from the trigger circuit 96. This trigger signal is supplied to the display unit 60 as a contact detection signal, thereby notifying that the contact has occurred.

That is, in response to the contact detection signal, the display unit 60 responds to it and displays, by letters or light emission, that the tip member 8 has contacted the inner wall of the living body 70.

When the contact is displayed, the operator immediately recognizes it and refrains from the bending operation.

As described above, when the tip member 8 comes into contact with the living body wall, the fact that the surgeon has made an operation to refrain from the bending operation is notified, so that the living body 70 can be prevented from being damaged by the bending.

Moreover, since the lead wire 42 of the first electrode 41 passes through the inside of the insertion portion 4, but the lead wire 43 of the second electrode 44 does not pass through the inside of the insertion portion 4, it is possible to avoid increasing the diameter of the insertion portion 4. . In other words, the diameter of the insertion part 4 can be reduced.

In this case, the detection sensitivity can be changed by adjusting the variable resistor 94. The material of the tip member 8 may be an insulator, but a material having a high dielectric constant is more sensitive.

The electrode 41 does not necessarily have to be embedded in the tip member 8, but may be exposed on the peripheral surface of the tip member 8 and the exposed surface may be coated (covered) with an insulator (electrically insulating material) or the like. Further, although the display unit 60 is used as the notifying means, a buzzer or a voice generating device may be used as the notifying means to notify the user of the contact by sound.

FIG. 4 shows an essential part of a second embodiment of the present invention, in which a control section 80 and a drive circuit 81 are used in place of the display section 60, and the movement of the tip of the insertion section 4 is regulated upon contact. There is.

That is, the drive circuit 81 controls the motor 21 for bending operation to the control unit.
It is driven to rotate in response to a command from 80, and when the detection unit 90 detects a contact, the drive of the motor 21 is immediately stopped and the movement of the tip of the insertion unit 4 is stopped. In this case, there is an advantage that the safety against excessive bending is further enhanced and the burden on the operator can be reduced.

In addition, the present invention can be used as, for example, an industrial endoscope, and in that case, even if the object to be inspected is hard, it is possible to prevent the tip member 8 from being scratched.

[Advantage of the Invention] As described above, according to the present invention, the first electrode provided at the distal end of the insertion portion, the second electrode capable of contacting the body surface,
One of the first and second electrodes is coated with an electrically insulating material, and a detection section for detecting contact between the tip of the insertion section and the living body wall based on a change in capacitance between these electrodes; Since the detection unit is provided with means for informing that when contact is detected or for restricting the movement of the tip of the insertion unit,
It is possible to provide an endoscope capable of detecting contact between the tip of the insertion portion and the living body without increasing the diameter of the insertion portion and preventing damage to the living body due to bending.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a main part and a correspondence between each electrode and a living body in a first embodiment of the present invention, FIG. 2 is a sectional view showing a tip member in the same embodiment, and FIG. FIG. 4 is a perspective view showing the overall construction of the embodiment in section, and FIG. 4 is a view showing the construction of the essential parts of the second embodiment of the present invention. 1 ... endoscope, 4 ... insertion part, 8 ... tip member, 8a ...
Groove, 41 …… first electrode, 42,43 …… lead wire, 44 …… second
Electrodes, 50 ... Detector, 60 ... Display (informing means), 70 ...
... living body.

Claims (1)

[Scope of utility model registration request] 1. An endoscope in which a distal end of an insertion portion is bendable, a first electrode provided at the distal end of the insertion portion, a second electrode capable of contacting a body surface, and first and second electrodes. One of these is coated with an electrically insulating material, and a detection unit that detects the contact between the tip of the insertion section and the living body wall based on the change in the capacitance between these electrodes, and this detection unit detects the contact. An endoscope, which is provided with a means for notifying that effect or restricting the movement of the distal end of the insertion part when the endoscope is operated.