JPS5818881Y2 - The best way to get started - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a bendable tube for an endoscope that can be bent freely by external pulling operation of a wire.

The tip section is equipped with an objective lens, etc., the operating section is equipped with an eyepiece lens and various devices necessary for endoscopic diagnosis, and the flexible tube has a built-in optical fiber bundle, bending operation wire, etc. In a general endoscope which is connected via a flexible tube, a bendable tube is provided between the tip and the flexible tube in order to tilt the tip in a desired direction, and the operating section is connected to the flexible tube. The wire that has been passed up to this point is pulled and bent.

As a conventional example of this type, there is one shown as a conventional example in Japanese Utility Model Publication No. 48-7829 or Japanese Utility Model Publication No. 48-31667. It is a bendable pipe in which a plurality of these are connected to form a short cylinder row, and the short cylinder row can be bent by overlapping and pivoting the connecting protrusions, or according to Utility Model Publication No. 47-30240. There is a device shown in the above publication, in which two crotches are provided at symmetrical positions on the end edge of a short cylinder, and a plurality of the short cylinders are connected by interweaving the two crotches, and the two crotches are connected to each other. This is a bendable tube that bends the entire tube by tilting the cylinders relative to each other using the fulcrum.

However, while the former method can maintain mechanical strength because it has multiple short tubes attached to each other, when the diameter of the short tubes is less than about 5 mm, it becomes difficult to attach a large number of short tubes to each other. It is extremely difficult.

Moreover, while the latter can eliminate the need for shaft attachment processing,
Since the connection is made by holding two crotches formed by a pair of protrusions, a connecting string made of nylon or the like is required as an auxiliary tool during the holding and assembling of the cylindrical row during the connection work, and it is difficult to thread the string through. There is extra work such as this, which causes various inconveniences.

Furthermore, if the nylon system is kept under tension after assembly, the supination flexibility will be lost, so it is necessary to keep the nylon system in a relaxed state, and as a result, there is no other choice but to create a loose state between the two forked retaining parts.

Since this backlash exists in many engagement parts, the entire body is susceptible to twisting, and when the operation part side is rotated by the necessary amount for endoscopic diagnosis, the curved part will be twisted, and the rotational displacement according to the necessary amount is not transmitted to the distal end, and the rotational position of the operating unit at hand does not match the direction of the distal objective lens, resulting in the observation direction of the subject being erroneous.

The present invention relates to a bendable tube that can eliminate the drawbacks of the conventional device as described above, has a simple structure, and does not cause twisting in the circumferential direction. explain.

As shown in FIG. 1, the bendable tube is made up of a large number of thin-walled short cylinders (hereinafter referred to as cylinders) 1 connected together.

A pair of support portions 2a are formed in the shape of a disk, facing each other at diametrically symmetrical positions on one end edge of the cylindrical body 1, and a support hole 2 is bored concentrically with the disk.

The semicircular part of the support part 2a protrudes from the cylinder 1 in the axial direction of the cylinder, and as is clear from FIGS. 1 and 3, the entire disk is recessed inside the cylinder 1 and the support The outer periphery of the part 2a and the cylindrical body 1
are staggered so that their inner circumferences are on the same straight line.

Therefore, the semicircle of the support portion 2a on the side of the cylinder 1 becomes a bent step, which is shown as a thin line in FIG.

A pair of tongues 3 are formed on the other end edge of the cylinder 1 at diametrically symmetrical positions, facing each other and protruding in the axial direction of the cylinder. It has become.

The width of the tongue piece 3 is large enough to fit loosely into the bearing hole 2, and the tongue piece 3
is bent inward and parallel to the cylindrical body 1 and staggered, and as is clear from FIGS.
a, and the distance between the inner periphery of the cylinder 1 and the outer periphery of the tongue piece 3 is equal to the thickness of the peripheral wall of the cylinder 1.

The inner peripheral wall of the cylindrical body 1 has a cut-out wire insertion hole 4 located in the middle of the tongue piece 3 (or the support part 2a).
is formed.

Note that, like the cylindrical body of a normal bendable tube, the supporting portion 2a and the tongue piece 3 are the apexes, and both ends of the cylindrical body 1 are similarly cut into a chevron shape.

A large number of cylindrical bodies 1 are connected together by inserting the tongue piece 3 of another cylindrical body 1 into the support hole 2 of one cylindrical body 1.

To do this, first place the other cylinder 1 at a slight angle with respect to one cylinder, insert the other tongue piece 3 into one of the support holes 2, and in this state rotate the other cylinder 1. If it is brought close to straight, the tip of the tongue piece 3 of the other cylindrical body 1 will be located outside of one of the support holes 2.

Next, bend the tip of the tongue piece 3 with the tip of a thin rod and push it into the support hole 2, and then rotate the other cylindrical body 1 further so that the other cylindrical body 1 becomes straight with the other cylindrical body 1. , the other tongue piece 3 is pushed into the support hole 2 and is in the inserted state, which is the same as the insertion state of the other side tongue piece 3 and the support hole 2.

In this state, as shown in the cross section of FIG.
The two cylindrical bodies are connected, and in this state, the two cylindrical bodies cannot be separated.

When a large number of cylindrical bodies 1 are connected in this manner and the wire 5 is inserted through the wire insertion hole 4, a bendable tube is formed.

It is the same as before that a tip end and a flexible tube are connected to the front and back of this bendable tube, and the tip of the wire 5 is fixed to a part of the tip end.

In use, when the rear end of the wire 5 is pulled, the stepped portions 3a of the tongues 3 of the multiple cylinders 1 slide along the support holes 2, causing each cylinder 1 to tilt, causing the entire pre-curved tube to curve. do.

As mentioned above, when connecting a large number of cylinders,
The tongue piece is inserted into the bearing hole while being deformed, and the tongue piece, the stepped part, and the bearing hole are connected by engaging with each other, so the connecting work can be easily and easily done manually, and when two or more pieces are connected, Since the connected state is maintained by the mating, the next cylinder can be connected without any auxiliary means.

Furthermore, when connected and used, each tongue piece and the support hole are pressed against each other by the wire and are in contact with each other, so even if a torsional force is applied around the axis of the bendable tube during use, it will not be twisted. The tip of the pre-curl is always oriented in the correct direction.

Furthermore, since the engaging portion between the tongue piece and the support hole is formed inside the cylinder, the outer periphery of the entire pre-curved tube has a smooth surface, making it easy to insert the flexible tube into the human body. can be done.

[Brief explanation of the drawing]

The drawings show an embodiment of the bendable tube for an endoscope according to the present invention, and FIG. 1 is a front view of the bendable tube, and FIG.
FIG. 3 is a side sectional view taken along line I-I in the figure, FIG. 3 is a top sectional view of FIG. 1, and FIG. 4 is a perspective view of the bendable tube. 1: Cylindrical body, 2: Bearing hole, 3: Tongue piece, 4: Step part, 5: Wire

Claims (1)

[Scope of utility model registration request] In a bendable tube for an endoscope, in which a large number of thin-walled short cylinders are connected to each other on the diameter of both edges, and the whole is bent by tilting in a direction perpendicular to the connecting part, A support portion having a circular hole is recessed inward to form the inner peripheral wall of the short cylinder and the outer peripheral wall of the support portion on the same plane, and the support portion is formed on the peripheral wall of the short cylinder on the diameter of the other edge. A tongue piece is formed parallel to the circumferential wall by bending inward through a step part on the same straight line as the hole, and the width of the tongue piece is made large enough to fit loosely in the support hole, and the step part is formed into a short cylindrical shape. The endoscope precircumflexion tube has the same thickness as the circumferential wall of the endoscope, and a large number of these short cylinders are connected by the tongue piece on one side and the support piece on the other side (1).