JPH01259830A - Preparation of spiral tube used in flexible tube of endoscope - Google Patents

Abstract

PURPOSE:To simply prepare a spiral tube free from a twist or difference in level, by forming a recessed groove to the outer peripheral surface of a thin- walled elongated metal pipe along the axial direction of said pipe and subsequently forming a spiral slit to the side wall of the metal pipe continuously over the total length thereof by a non-contact metal cutting means to form the spiral tube. CONSTITUTION:A recessed groove 11a is formed to the outer peripheral surface of a metal pipe 1 along the axial direction thereof by press molding. Subsequently, a non-contact metal cutting means 100 is arranged to the side part of the metal pipe 1. As the metal cutting means 100, for example, a laser processing machine for emitting carbon dioxide gas laser or other laser beam as fine beam or a discharge processing machine is used. The metal pipe 1 is supported at one end thereof by a support jig 101 and moved in the axial direction at a definite speed while rotated at definite angular velocity and the side wall thereof is cut in a narrow width by intense heat. By this processing, a spiral slit is continuously formed to the metal pipe 1 over the total length thereof to form a spiral tube 12.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a helical tube used for a flexible tube that forms the insertion portion of an endoscope, and in particular, relates to a method for manufacturing a helical tube used for a flexible tube forming an insertion portion of an endoscope. The present invention relates to a method of manufacturing a spiral tube in which a concave groove is formed.

[Prior Art] A conventional flexible tube for an endoscope is generally a helical tube made of a thin stainless steel strip, the outside of which is covered with a mesh tube, and the outside of which is covered with a flexible tube made of a synthetic resin material. It was covered with an outer skin and was formed into an elongated cylinder with a circular cross section. Therefore, the spiral tubes used therein have been manufactured by simply winding a stainless steel strip or the like in a spiral shape with a uniform diameter.

[Problem to be solved by the invention] In a general endoscope, the channels are MT+! It is inserted into the tube. However, when it is desired to add second and third forceps channels, the additional forceps channels must be placed along the outside of the flexible tube, and to prevent infection from occurring.

Channels may be disposable after each use. In such a case, the channel is arranged along the outside of the flexible tube (Japanese Patent Application Laid-open No. 5i-179128 [)
.

However, the flexible tube of conventional endoscopes had a simple circular external shape, so if the channel was placed along the outside of the flexible tube, the channel would protrude from the flexible tube, impairing insertion into the body cavity. It had the drawback of causing significant pain to those with 11w.

Therefore, it is conceivable to form a concave groove along the tube axis direction on the outer peripheral surface of the =T flexible tube and accommodate the channel in the concave groove from the outside. However, the flexible tube of an endoscope has sufficient strength against bending and crushing. It must have sufficient flexibility to bend effortlessly along the inner wall of the patient's body cavity, and for this purpose, it is essential to use a helical tube made of a thin-walled, highly hard material. However, when a concave groove along the tube axis is formed in a helical tube, the helical tube becomes twisted due to distortions during processing that remain during formation, making it difficult to form the concave groove straight. The helical tube also has a step between each turn, which causes an inconvenience in that the optical fiber mold or the like can get caught in the step and be damaged. Due to such inconveniences, it has conventionally been extremely difficult to form grooves straight along the tube axis on the outer circumferential surface of the helical tube.

The purpose of this invention is to provide a method for manufacturing a helical tube used for a flexible tube of an endoscope, which solves such conventional problems and can easily manufacture a helical tube without twists or steps. shall be.

[Means for Solving the Problems] In order to achieve the above object, a method for manufacturing a helical tube used for a flexible tube of an endoscope according to the present invention includes a method for manufacturing a helical tube used for a flexible tube of an endoscope according to the present invention. After forming the concave groove along the direction,
A spiral pipe is manufactured by continuously forming a spiral slit along the entire length of the side wall of the metal pipe using a non-contact metal cutting means.

[Operation] A concave groove is first formed in the metal pipe, and then a spiral slit is formed in the metal pipe by a non-contact metal cutting means to produce a helical tube with a concave structure.

[Example] Examples will be described with reference to the drawings.

FIG. 1 shows a thin-walled, elongated metal pipe l that is the raw material for the helical tube used in the flexible tube of the present invention. The pipe 1 used has a uniform diameter over its entire length. However, it is also possible to use one in which the diameter changes partially or over the entire length.

In the present invention, first, a groove 11a is formed on the outer circumferential surface of the metal pipe 1 along the tube axis direction. This groove 1
1a can be formed by press molding, and FIG. 2 shows a state in which a groove 11a is formed in the metal pipe l. In this state, the metal pipe 1 may be subjected to solution treatment to remove strain, and then subjected to age hardening treatment to make it highly hard. In this case, for example, beryllium is used as the material for the metal pipe 1. Although a precipitation-hardening alloy material such as copper must be used, since a material with low hardness before treatment can be used, the groove 11a can be easily formed, and the remaining distortion due to forming can be completely eliminated. can be removed.

Next, as shown in FIG. 3, a non-contact metal cutting means 100 is placed on the side of the metal pipe 1. As the metal cutting means lOO, for example, a laser processing machine that irradiates a thin beam with a carbon dioxide laser or other laser beam, or an electrical discharge machine that cuts the metal by utilizing a discharge phenomenon between electrodes, or the like is used.

Then, as shown in FIG. 3, one end of the metal pipe 1 is supported by a support 101, and the metal pipe 1 is moved at a constant speed in the tube axis direction while rotating at a constant angular velocity. Then, the side wall of the metal pipe 1 is irradiated with a laser or discharged with a thin beam, and the metal pipe 1 is exposed to high heat.
Cut the side wall to a narrow width. Through this processing, a spiral slit is continuously formed over the entire length of the metal pipe 1, and the metal pipe 1 becomes a spiral tube 12. Incidentally, in order to prevent the laser beam or the like from penetrating the metal pipe 1, it is preferable to insert a core metal or the like into the metal pipe 1 at the time of heating T1.

If such a process of cutting the metal pipe 1 into a spiral shape was performed by the mechanical process 1, irregular twists and steps would occur in the helical tube 12 due to distortions caused during the process, so the endoscope It is useless for flexible pipes.
However, non-contact metal cutting means such as laser machining and electrical discharge machining instantly cut the metal wall at high temperature without contact, so almost no distortion occurs in the spiral tube 12, and there are no twists, steps, etc. It is possible to make a V1 swirl tube 12 that is not straight.

FIG. 4 shows the completed spiral tube 12, in which the groove 11a remains straight even when left alone.

In order to manufacture a flexible tube for an endoscope, a reticular tube 13 is tightly coated on the outside of the spiral tube 12 thus formed, as shown in FIG. Cover. The mesh tube 13 is made by knitting an extremely thin stainless steel wire having a diameter of, for example, 0.1 layers or less into a tubular shape.

The outer skin 14 is formed of, for example, a polyurethane resin-based synthetic resin. The outer skin 14 is formed by applying molten resin to the outer surface of the reticular tube 13 by extrusion molding or the like. Alternatively, an outer skin previously formed into a tube shape may be tightly attached to the outer surface of the reticular tube 13 by heat processing, vacuum suction, or the like.

A base (not shown) is attached to both ends of the flexible tube IO thus formed by soldering or the like, and the tube is assembled into an endoscope as shown in FIG. 7.

In FIG. 7, reference numeral 2 denotes a distal end main body containing an objective lens (not shown), etc., and 3 a curved portion that can be bent freely by remote control. Reference numeral 4 denotes an operating section in which various operating devices are built in, and a bending operation knob 5 for remotely controlling the bending of the bending section 3 is rotatably provided on its side wall. Reference numeral 10 denotes a flexible tube manufactured by the manufacturing method of the present invention, which connects the operating section 4 and the bending section 3. 11 is a flexible tube l
This is a U-shaped groove formed on the outer peripheral surface of O along the tube axis direction, and the grooves 21 and 31 are continuous with the groove y4ii.
However, it is also formed on the tip main body 2 and the curved portion 3.

In the above embodiment, a single spiral tube was used, but as shown in FIG. 5, a plurality of spiral tubes 12a and 12b having different winding directions may be closely stacked and used. By doing so, the strength of the flexible tube against twisting is improved.

[Effects of the Invention] According to the method of manufacturing a helical tube used for a flexible tube of an endoscope according to the present invention, a groove is formed in a metal pipe, so compared to forming a groove in a spiral tube. Processing is very simple, and since the metal pipe is then cut in a spiral shape using a non-contact metal cutting method to form a spiral tube, there is almost no distortion caused by processing, and grooves are formed. It has an excellent effect of being able to easily form a straight spiral tube without twisting or steps.

[Brief explanation of the drawing]

1 to 3 are perspective views showing the steps of an embodiment of the present invention, FIG. 4 is a perspective view of a spiral tube formed according to the present invention, and FIG. 5 is a perspective view of the spiral tube in a double layered state. A perspective view, FIG. 6 is a sectional view of a flexible tube formed using a spiral tube formed according to the present invention, and FIG. 7 is a perspective view of an endoscope constructed using the flexible tube. . l... Metal pipe, 10... Flexible tube, 11... Concave groove, 11a... Concave groove, 12... Spiral tube, 13...
Reticular tube, 100... Metal cutting means, 101... Supporting tool. Agent Patent Attorney Kazuhiko Mitsui Figure 4 Figure 5 Figure 6 Figure 7

Claims (3)

[Claims] (1) After forming a concave groove along the tube axis on the outer peripheral surface of a thin-walled elongated metal pipe, a spiral slit is continuously cut along the entire length of the side wall of the metal pipe using a non-contact metal cutting means. 1. A method for manufacturing a helical tube used for a flexible tube of an endoscope, characterized in that the helical tube is manufactured by forming the helical tube. (2) The method for manufacturing a helical tube used for a flexible tube of an endoscope according to claim 1, wherein the metal cutting means cuts the side wall of the metal pipe with a laser beam. (3) The method of manufacturing a helical tube used for a flexible tube of an endoscope according to claim 1, wherein the metal cutting means cuts the side wall of the metal pipe by electric discharge machining.