JPS6320138B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an endoscope length measuring tool for measuring the size of a protruding diseased part in a body cavity.

Generally, when treating an affected area in a body cavity, such as a polyp, a length measuring instrument is inserted instead of forceps into the forceps insertion channel of the endoscope, and the size of the polyp is measured using this length measuring instrument. It is well known that it is useful for diagnosis, treatment, etc.

By the way, conventional length measuring tools have a pair of arms that can be opened and closed at the tip of the outer tube, and a slide shaft is inserted into the outer tube, and this slide shaft is connected to an operating section provided at the rear end of the outer tube. The pair of arms are opened and closed according to the size of the polyp by moving forward and backward, and the amount of opening of these arms is determined based on the amount of movement of the slide shaft.

By the way, according to the length measuring tool with this configuration,
When the outer tube is not bent, that is, when it is used by being inserted through the forceps insertion channel of a rigid endoscope, the amount of advancement and retraction of the slide shaft is likely to match the amount of opening of the pair of arms, so that the affected area However, when used in a flexible endoscope, the outer tube is bent together with the endoscope insertion section, so the size of the outer tube can be known relatively accurately. Therefore, a difference arises in the amount of movement of the slide shaft between the distal end and the rear end of the outer tube. Therefore, the amount of movement of the slide shaft and the amount of opening/closing of the pair of arms are not constant, making it impossible to accurately determine the size of the affected area from the amount of movement of the slide shaft, which is critical for diagnosis and treatment. This caused an inconvenience.

This invention was made based on the above circumstances, and its purpose is to elastically deform a pair of arms according to the size of the affected area, open the arms,
To provide a length measuring tool for an endoscope, which can always accurately determine the size of an affected area regardless of the bending state of an outer tube by electrically detecting the amount of deformation at that time. It is in.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the figure, reference numeral 1 denotes a flexible outer tube formed of, for example, a close-contact coil. A cylindrical base 3 in which a slider 2 is movably housed is attached to the tip of the outer tube 1, and an operating section main body 4 is attached to the rear end. Above cap 3
A screw 1 is attached to the inner wall of the rear end of the first arm 5 and the second arm 6 having the same length so that they overlap.
It is fixedly provided at points a and 1a. Of the pair of arms 5 and 6, the second arm 6 is usually made of a straight elastic material, and the tip of the second arm 6 has a string 7 connected to the slider 2 at one end. The ends are connected. Furthermore, a strain gauge 8 is attached near the fixed end of the second arm 6 with adhesive or the like. Therefore, when the slider 2 is displaced and pulls the string 7,
As shown by the solid line in FIG. 1, the second arm 6 is elastically deformed, and the tips of the first and second arms 5, 6 are separated by a predetermined distance l, and the second arm 6 at this time is The amount of deformation is electrically detected by the strain gauge 8 as described later. Note that the string 7 is attached to the second arm 6
When it is elastically deformed, it comes into contact with a guide roller 9 provided on the inner wall of the cap 3.

Further, a wire 10 inserted through the outer tube 1 is connected to the slider 2 at one end. The other end of this wire 10 is connected to an insertion shaft 12 that is inserted into a through hole 11 bored in the operating section main body 4 so as to be movable forward and backward. A locking rod 13 is protruded from the operating shaft 12, and the locking rod 13 is inserted into a guide hole 14 formed in the operating section main body 4. Therefore, the locking rod 13, that is, the operating shaft 12, can be moved back and forth within the length range of the guide hole 14, and by moving it back and forth within this range, the wire 10, slider 2, and string can be removed. The second arm 6 is opened and closed with respect to the first arm 5 via the arm 7.

On the other hand, a lead wire 15 is connected to the strain gauge 8, and this lead wire 15 is led out from a through hole 16 drilled in the operating section main body 4, and connected to a bridge circuit 17 shown in FIG. There is. A bridge power supply 18 is connected to the bridge circuit 17 via a balance adjustment circuit 19. A display device 23 is connected to the output side of the bridge circuit 17 via an AC amplifier 20, an AC/DC conversion circuit 21, and a DC amplifier 22.
are connected sequentially. Further, the bridge power supply 18 is connected to the input side of the AC amplifier 20 via a calibration circuit 24. Therefore,
When the second arm 6 is elastically deformed and the resistance value of the strain gauge 8 changes, the amount of change in the resistance value of the strain gauge 8, that is, the amount of deformation of the second arm 6 is displayed on the display device 23. It's becoming like that.

Therefore, in the length measuring instrument having the above structure, in order to find out the size of the affected area, the second arm 6 is elastically deformed by pulling the operation shaft 12, and the second arm 6 and the first arm 5 are connected. Match the distance between the tips of the needle to the size of the affected area. Then, at this time, the resistance value of the strain gauge 8 attached to the second arm 6 changes depending on the amount of deformation of the second arm 6.
A voltage flows through the bridge circuit 17 which is maintained in a balanced state, and this voltage value is displayed on the display device 23, whereby the amount of deformation of the second arm 6, that is, the first amount corresponding to the size of the affected area is determined. The distance between the tips of arm 5 and second arm 6 can be known.

That is, according to the length measuring tool having the above configuration, since the amount of deformation of the second arm 6 is converted into an electric signal to determine the size of the affected area, the wire 10 for deforming the second arm 6 is , the size of the affected area can be accurately determined regardless of the amount of movement of the slider 2 and string 7. Therefore, when using the length measuring tool by inserting it into the forceps insertion channel of a flexible endoscope, the length measuring tool bends together with the endoscope, and the amount of movement of the wire 10 and the string 7 and the second arm are bent. Even if the amounts of elastic deformation of No. 6 do not match, the size of the affected area can be reliably known.

Note that this invention is not limited to the above embodiment,
For example, a configuration as shown in FIG. 3 may be used. That is, in this embodiment, only the part of the second arm 6 where the strain gauge 8 is attached is made into an elastic part 6a, and the other parts are made into rigid parts 6b, 6b. Since only the elastic portion 6a is elastically deformed, the amount of deformation of the elastic portion 6a, that is, the amount of opening of the second arm 6 can be determined more accurately by the strain gauge 8 attached to this portion.

Further, the means for opening and closing the second arm 6 is
This may be done by directly connecting the operating shaft 12 and the tip of the second arm 6 with a wire or the like.

Furthermore, the outer tube may be composed of not only a tight coil but also a flexible tube.

As described above, the present invention includes a pair of arms having at least a portion of the elastic portion at the distal end of an outer tube, an operating means for elastically deforming the elastic portion to open and close the pair of arms, and an operating means for operating the pair of arms by elastically deforming the elastic portion, and The device includes a detection means for electrically detecting the amount of elastic deformation of the provided elastic portion, and a detection circuit for detecting the amount of electrical change in the detection means. Therefore, when the length measuring instrument of the present invention is used in a flexible endoscope or the like, even if the outer tube is bent along with the endoscope, the length measurement tool of the pair of arms can be adjusted according to the size of the affected area regardless of the bent state. There is a great practical advantage in that the amount of opening, that is, the amount of elastic deformation of the arm can be accurately determined by the electrical signal from the detection means provided on the arm.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted cross-sectional view of a length measuring tool showing one embodiment of the present invention, Fig. 2 is a block diagram showing the control circuit of the strain gauge, and Fig. 3 is a diagram showing another embodiment of the invention. FIG. 3 is a sectional view of the tip of the length measuring tool shown in FIG. DESCRIPTION OF SYMBOLS 1... Outer tube, 4... Operating unit main body, 5... First arm, 6... Second arm, 7... Strap, 8...
...Strain gauge, 10...Wire, 12...Operation axis, 17...Bridge circuit (detection circuit), 23...
...display device.

Claims (1)

[Claims] 1. An outer tube, a pair of arms provided at the tip of the outer tube and having at least a portion of an elastic part, an operating means for elastically deforming the elastic part of the arms to open and close the pair of arms, and The device is characterized by comprising: a detection means provided on the elastic portion for electrically detecting the amount of elastic deformation of the elastic portion of the arm caused by the operating means; and a detection circuit for detecting the amount of electrical change in the detection means. Length measurement tool for endoscopy.