JPH0430289B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electric endoscope that uses a motor as a drive source to bend an insertion section.

[Technical background of the invention and its problems]

In recent years, in order to improve the operability of bending the insertion tube, endoscopes have been proposed in which the bending operation mechanism is driven by a motor to bend the insertion tube (for example, -45790, JP-A-58-78635).

However, when the bending drive of the insertion section is motorized in this way, there is a problem that when performing a bending operation, the bending state of the insertion section and the magnitude of the load at that time cannot be easily perceived by the touch of the hand. For this reason, the insertion tube may be curved more than necessary inside the body cavity, and the tip of the insertion tube may press strongly against the body cavity wall, and in the worst case, it may cause damage to the body cavity wall.
The danger remained. In this regard, with conventional endoscopes, the curvature of the insertion tube and the magnitude of the load at that time can be easily detected by the feel of the hand operating the angle knob, so the above-mentioned dangers are less likely to occur.
This problem has been avoided, but this problem cannot be achieved with electric endoscopes.

[Purpose of the invention]

This invention was made in view of the above circumstances, and its purpose is to provide an electric endoscope that can ensure safety when an abnormal load is applied during bending of the insertion section. It is about providing.

[Summary of the invention]

That is, the present invention provides a detection means for detecting that the load current of the motor that drives the insertion section to bend is equal to or higher than a predetermined value, and provides a notification means for notifying based on this detection means, thereby preventing the insertion section from bending. When an abnormal load is sometimes applied, the system notifies the operator that the current situation is dangerous so that the danger can be avoided.

[Embodiments of the invention]

The present invention will be described below based on an embodiment shown in the drawings. FIG. 1 shows a schematic configuration of an electric endoscope, and 1 is the endoscope main body. The endoscope main body 1 is
It is composed of an operating section 2, an insertion section 3, and a light guide cable 4. The insertion section 3 has a curved tube section 6 at the distal end of the flexible tube section 5, and a distal end member 7 is attached thereto. They are constructed so that they are pivoted to each other, allowing them to bend freely up and down and left and right. In addition, the tip member 7 includes a light guide 1.
In addition to the exit tip 11 of the image guide 13 and the objective lens 12 arranged therein, the entrance tip 14 of the image guide 13 is arranged opposite to the objective lens 12 . The other end of the light guide 10 is guided into the light guide cable 4 through the insertion section 3 and the operation section 2, so that it can be connected to a light source device (not shown). . The other end of the image guide 13 is guided through the insertion section 3 and the operation section 2 to an eyepiece 15 provided in the operation section 2, and faces an eyepiece 16 and a mask 17 built into the eyepiece 15. It is installed. That is, the front of the objective lens 12 can be seen from the eyepiece 15. An LED 18 is provided as a light emitter on the outer periphery of the mask 17 that forms the field of view of the eyepiece 15.
(equivalent to notification means) is provided. For more information,
As shown in FIG. 2, the LED 18 has a light-emitting part located in a notch 17a provided on the outer periphery of the mask 17 to display the upper and lower positions within the field of view.
It is installed so that it can be seen from 5.

On the other hand, the operating section 2 is provided with a bending mechanism 20 for remotely controlling the bending tube section 6 of the insertion section 3. Note that although only the vertical bending operation mechanism 20 is shown in the drawing, a left and right bending operation mechanism is also provided.

Here, to explain the bending operation mechanism 20, 21 is a motor that can freely rotate in forward and reverse directions, 22 is a drum, 22a is a reduction mechanism composed of, for example, two gears, and 23a and 23b are a pair of upper and lower operation wires. . The speed reduction mechanism 22a is interposed between the output shaft of the motor 21 and the rotating shaft of the drum 22, so that the drum 22 can be rotated forward and backward under reduced rotation speed by driving the motor 21.
The operation wire 23 is attached to this drum 21.
In addition to wrapping the proximal ends of tubes a and 23b from opposite sides, the distal ends of each tube are passed through the insertion section 3 and inserted into the curved tube section 6.
The ends of each tip are connected to the upper and lower parts of the most advanced indirect member 8, and the drum 22 is driven by the motor 21.
As the operation wires 23a, 2 rotate, one of the operation wires 23a, 2
3b is wound around the drum 22 and pulled, and at the same time, the other operating wires 23a, 23b are let out so that the curved tube part 6 can be bent in the direction in which it is pulled. Note that deflection removers 24, 24 are interposed in the middle of the operating wires 23a, 23b, respectively. Then, these operation wires 23a, 2
3b is electrically connected to a bending operation knob (curving operating member) 28 rotatably provided on the operating section 2 via a drive device 26,
The operator (not shown) manually presses the bending operation knob 28.
By rotating backward, the curved tube section 6 in a straight state can be gradually raised, and by rotating the curve operation knob 28 forward, the curved tube section 6 can be gradually machined. There is. Specifically, its structure includes, for example, a potentiometer (not shown) is provided on each rotating shaft of the drum 22 and the bending operation knob 28, and the drive device 26 is configured to adjust the amount of rotational operation output from each of these potentiometer motors. It is composed of a servo circuit that compares the corresponding output voltages and outputs a drive signal to the motor 21 according to the difference, so that the motor 21 can be rotationally driven according to the direction and amount of rotation of the bending operation knob 28. There is. It goes without saying that when the curved tube section 6 is in a straight line state, the curve operation knob 28 is at a neutral position in the middle thereof.

On the other hand, in addition to the aforementioned drive device 26, the motor 21 of the bending operation mechanism 20 configured in this manner is equipped with a detection circuit that detects a state in which it is dangerous to bend the insertion portion 3 any further due to the overcurrent of the motor 21. 30 are connected. This detection circuit 30 is built into the operating section 2, and its schematic configuration is shown in FIG. 1 and the detailed configuration is shown in FIG. 3.

Here, to explain the detection circuit 30, 3
1 is a comparator, 32 is a motor 21 and a resistor 3
A current detection circuit configured by connecting 3 in series,
34, a reference value generation circuit configured by connecting a resistor 35 and a Zener diode 36 in series; 37;
The above LED is connected to the output section of the comparator 31.
18 and a resistor 38 are connected to each other. Then, the motor 21 and the resistor 33 are connected to the negative side of the comparator 31, and the resistor 35 and the Zener diode 3 are connected to each other.
6 to the positive side of the comparator 31, each current detection circuit 32, reference value generation circuit 3
4 and a comparison drive circuit 37 are connected in parallel to a DC power supply 39 to constitute the whole. (Detection means) That is, in the current detection circuit 32, the motor 21
From the difference between the voltage obtained from the current when the motor 21 is operating normally and the voltage obtained from the change in inductance when the motor 21 is energized but mechanically stopped (increase in load), In addition to detecting when it is dangerous to bend the LED 18, the reference value generating circuit 34 uses the Zener voltage V ₂ as a reference value to determine when the LED 18 should operate. The Zener voltage V ₂ (reference value) input to the comparator 31 is the voltage V ₁ generated in the motor 21 and the resistor 33 when the motor 21 operates normally.
(V ₂ > V ₁ ), and when the motor 21 operates normally, the comparator 31
output a positive signal from LED1
In addition to disabling the light emission of 8, the motor 21
The LED 18 is designed to emit light by outputting a negative signal from the comparator 31 only when the motor stops mechanically (when the voltage V ₁ on the motor 21 side increases) even though the motor 21 is applying current. I have to. However, no more insertion part 3
When it becomes dangerous to bend the
A warning can be issued by emitting light within the field of view of the LED 18.

When operating the bending tube section 6 of the insertion section 3 using the electric endoscope configured in this manner, the bending operation knob 28 is rotated. As a result, the bending operation knob 2 is adjusted according to the amount of rotation from the neutral position.
The output from the potentiometer (not shown) on the drum 22 side changes, and a difference occurs between the output value and the output from the potentiometer (not shown) on the drum 22 side. Then, such a difference is calculated by the drive device 26, and the motor 21 is servo-driven so that the difference becomes zero.
The curved pipe portion 6 is bent by rotating and pushing and pulling the operating wires 23a and 23b. Thereafter, when the output of each potentiometer (not shown) becomes zero, the operation of the motor 21 is stopped.
The bending action of the bending tube section 6 will stop.

Here, it has been pointed out that with such electric endoscopes, when performing a bending operation as mentioned earlier, the magnitude of the load state of the curved insertion section 3 cannot be easily felt by the touch of the hand. Although there is a risk that the distal end of the insertion portion 3 may strongly press against the body cavity wall and cause damage to the body cavity wall, this invention can avoid such a risk.

In other words, when the insertion portion 3 is bent more than necessary in the body cavity, and a danger is expected,
The tip member 8 of the insertion section 3 strongly presses against the body cavity wall,
As the amount of operating force increases, the load on the motor 21, which was operating smoothly, increases. And no more,
When the motor 21 becomes unable to bend, it will mechanically stop due to an excessive load even if current is applied to the motor 21. As a result, the inductance of the motor 21 becomes smaller, and as a result, the voltage V ₁ becomes larger than the Zener voltage V ₂ . Thus, until now, the Zener voltage
The LED 18, which did not operate because V ₂ was larger than the voltage V ₁ on the motor 21 side, will emit light within the field of view as the voltage V ₁ on the motor 21 side increases (V ₁ > V ₂ ). .

Therefore, the operator looking into the field of view can see from the light emission of the LED 18 that further bending is dangerous, and can use this as a warning to prevent dangerous operations. In other words, abnormalities can be detected visually, and the bending operation knob 28 can be
This prevents continuous operation of the .

In addition, in the above-mentioned embodiment, an LED was provided in the notch of the mask, and the LED was operated at a predetermined current value to issue an alarm.
The LED may be provided on the outer periphery of the visual field other than the notch, and the LED may also be one that gradually changes its emitted color from one color to a different color depending on the amount of operating force (load). Alternatively, multiple types of LEDs may be arranged in parallel and the emitted light color may be changed depending on the amount of operating power (load). In addition, a control element such as a Hall element may be used to operate the light emission of the LED.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to notify the operator that if the insertion tube bends any further, it will be in a dangerous state, thereby preventing the operator from continuing to unnecessarily bend the insertion tube. It becomes like this.

Therefore, problems arise with electric endoscopes.
It is possible to ensure safety when an abnormal load is applied during the bending operation of the insertion section, and to avoid the danger of damaging the body cavity wall.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a partially cutaway perspective view showing the schematic configuration of an electric endoscope;
FIG. 2 is a front view showing the state in which the light emitter is attached within the visual field, and FIG. 3 is a circuit diagram showing the detection circuit. 3... Insertion section, 6... Curved tube section, 15... Eyepiece section, 17... Mask, 18... LED (notification means),
20...Bending operation mechanism, 21...Motor, 28...
...Curving operation knob, 30...Detection circuit (detection means).

Claims (1)

[Claims] 1. In an electric endoscope that uses a motor as a drive source to drive a bending operation mechanism to bend an insertion section, the detection means detects when the load current of the motor exceeds a predetermined value, and the detection means An electric endoscope characterized in that it is provided with a notification means for making a notification based on the following.