JP2001235073A - Structure and method for connecting endoscope tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure and a method for connecting an endoscope tube that can firmly connect a flexible tube and a connection member without heating. SOLUTION: A hard connection member 2 formed with pointed circumferential projections 3 on the periphery is inserted in an end of a flexible tube 1. That portion of the flexible tube 1 which receives the inserted connection member 2 is not heated to its softening point but pressured radially from the periphery with a press die, so that the circumferential projections 3 bite into the wall portion of the flexible tube 1 from the interior thereof to thus connect the connection member 2 and the flexible tube 1 where the wall portion is brought into close contact with substantially all the surfaces of the circumferential projections 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure and a connection method for an endoscope tube used in an endoscope and a treatment tool for the endoscope.

[0002]

2. Description of the Related Art As a connection structure of an endoscope tube used for an endoscope or an endoscope treatment tool, a connected member having irregularities formed on an outer peripheral surface is provided inside an end of a flexible tube. Although a press-fitting structure is generally used, there are many cases where sufficient connection strength cannot be obtained.

[0003] There is a type in which a male screw is formed on the outer peripheral surface of a connected member and is screwed into a flexible tube like a die to connect the connected member and the flexible tube. The screw may be loosened and the connected member may fall off the flexible tube.

Therefore, conventionally, after the member to be connected is press-fitted into the end of the flexible tube, the flexible tube is deformed by heating to adhere to the member to be connected, thereby increasing the connection strength ( Japanese Patent Publication No. 3-29407, 51-158
No. 191).

[0005]

In order to deform a flexible tube made of a synthetic resin such as ethylene tetrafluoride resin by heating, it is necessary to heat the tube to the softening point of the tube.

However, the flexible tube heated to the softening point is softened and cannot maintain its shape, and is extremely softened even when the temperature rises by several degrees from the softening point. There are many cases where the state is transformed into a state.

Accordingly, an object of the present invention is to provide a connection structure and a connection method of an endoscope tube which can firmly connect a flexible tube and a member to be connected without heating.

[0008]

In order to achieve the above-mentioned object, a connecting structure for an endoscope tube according to the present invention comprises a rigid connected member having a circumferential projection having a sharp tip formed on an outer peripheral surface. The connected member is inserted into the end of the flexible tube, and the peripheral projection is cut into the flesh portion from the inner peripheral surface of the flexible tube and the flesh portion is in close contact with almost the entire surface of the peripheral projection. Is connected to the sex tube.

[0009] A plurality of circumferential projections may be protruded from the connected member at intervals in the axial direction, and the outer diameter of the flexible tube at the portion connected to the connected member may be reduced. It should be constant.

In the method for connecting an endoscope tube according to the present invention, a rigid connected member having a peripheral projection having a sharp pointed tip formed on an outer peripheral surface is inserted into an end of a flexible tube. By pressing the flexible tube radially from the outer peripheral surface with a press die without heating the flexible tube to the softening point at the portion where the member is inserted, the circumferential protrusions bite into the fleshy portion from the inner peripheral surface of the flexible tube. Thus, the connected member and the flexible tube are connected so that the fleshy portion is in close contact with substantially the entire surface of the circumferential projection.

It is preferable that the flexible tube is rotated around an axis relative to the surface of the press mold in a state where the flexible tube is pressed by the press mold. The outer diameter of the flexible tube may be constant.

[0012]

Embodiments of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes a flexible tube made of a synthetic resin material such as a tetrafluoroethylene resin or a polyethylene resin, which is used for passing a fluid in an endoscope, or for an endoscope. It is used as a sheath of a treatment tool.

Reference numeral 2 denotes a connected member such as a base pipe or a mechanical part connected to the end of the flexible tube 1, and is formed of a hard material such as a metal such as stainless steel or a hard plastic. ing.

In this embodiment, the connected member 2 is cylindrical, the inner diameter of the flexible tube 1 is substantially equal to the inner diameter of the connected member 2, and the outer diameter of the flexible tube 1 is Is smaller than the outer diameter of the connected member 2.

The connection member 2 is formed to have a smaller outer diameter at a connection portion A with the flexible tube 1 than at other portions. On the outer peripheral surface of the portion, for example, three circumferential projections 3 each having a sharp tip are formed so as to protrude at an interval from each other in the axial direction.

Each of the peripheral projections 3 is formed such that the side facing the end of the connected member 2 is inclined and the back surface thereof is formed in an umbrella shape perpendicular to the axis. It is located at a position lower than the inside diameter.

FIG. 1 shows a flexible tube 1 and a connected member 2.
Are connected to each other, the small-diameter portion of the connected member 2 is inserted into the end of the flexible tube 1, and each of the circumferential projections 3 is moved from the inner peripheral surface of the flexible tube 1 to the inside of the flesh portion. The fleshy portion of the flexible tube 1 is brought into close contact with almost the entire surface of the circumferential projection 3.

In the connection portion A, the outer surface of the flexible tube 1 has no irregularities, and the outer diameter of the flexible tube 1 is constant. In this example,
The outer diameter of the connection portion A is the same as the outer diameter of the connected member 2.

FIG. 2 shows a flexible tube 1 and a connected member 2.
FIG. 2 shows a connection method for connecting the small-diameter portion of the connected member 2 to the end of the flexible tube 1 simply by press-fitting. The inner peripheral surface of the flexible tube 1 is in contact with the pointed end of the flexible tube 3, and the diameter of the flexible tube 1 is expanded at that portion.

Therefore, the flexible tube 1 is pressed around the axis with respect to the surface of the press dies 101 and 102 while being pressed radially from the outer peripheral surface by the press dies 101 and 102 without heating. By rotating, the circumferential protrusion 3 bites into the fleshy portion of the flexible tube 1.

Then, when the fleshy portion of the flexible tube 1 comes into close contact with almost the entire surface of the circumferential projection 3, the connection operation is completed. By doing so, the flexible tube 1 and the connected member 2 can be connected to each other in a very strong state against a pulling force or the like without heating the flexible tube 1. Even if the flexible tube 1 and the connected member 2 are relatively rotated around the axis, the connection state is not loosened.

FIGS. 3 to 5 exemplify a specific connection operation for executing the connection method shown in FIG. 2. In the example shown in FIG. 3, the connected member 2 is inserted into the end. The flexible tube 1 in the state is pressed into two press molds 1 having flat surfaces.
The flexible tube 1 is pushed and rolled while the surface of the flexible tube 1 is pressed by one of the press dies 101 between the first and second molds 01 and 102.

In the example shown in FIG. 4, a groove 103 having a semicircular cross-sectional shape having a size corresponding to the outer diameter of the flexible tube 1 after connection at the connection portion A is formed on both press dies 101, The flexible tube 1 is rotated around the axis together with the connected member 2 while the flexible tube 1 is pressed from both sides at the groove 103.

In the example shown in FIG. 5, the same press dies 101 and 102 as used in FIG.
In a state where the flexible tube 1 is sandwiched and pressed by the portion,
The press dies 101 and 102 are rotated around the axis of the flexible tube 1.

FIG. 6 shows a connection structure of an endoscope tube according to a second embodiment of the present invention, in which the cross-sectional shape of the circumferential projection 3 is substantially a regular triangle. As described above, the cross-sectional shape, the number, and the like of the peripheral protrusions 3 may be appropriately selected as needed.

Further, in this embodiment, the outer diameter of the flexible tube 1 and the connected member 2 are substantially equal, and the inner diameter of the flexible tube 1 is larger than the inner diameter of the connected member 2. .

[0027]

According to the present invention, the flexible tube and the member to be connected can be connected to each other in a very strong state against a tensile force or the like without heating. Even if the connected member is relatively rotated around the axis, the connection state is not loosened.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a first embodiment of a connection structure for an endoscope tube according to the present invention.

FIG. 2 is a side sectional view of an embodiment of a method for connecting an endoscope tube according to the present invention.

FIG. 3 is a schematic view of a first specific example of a method for connecting an endoscope tube according to the present invention.

FIG. 4 is a schematic view of a second specific example of the method for connecting an endoscope tube according to the present invention.

FIG. 5 is a schematic view of a third specific example of a method for connecting an endoscope tube according to the present invention.

FIG. 6 is a side sectional view of a second embodiment of the endoscope tube connection structure of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flexible tube 2 Connected member 3 Peripheral protrusion A Connection part

Claims (6)

[Claims] 1. A rigid connected member having a peripheral projection having a sharp point formed on an outer peripheral surface is inserted into an end of a flexible tube, and the peripheral projection is formed on an inner peripheral surface of the flexible tube. The endoscope tube, wherein the connected member and the flexible tube are connected to each other so that the flesh portion comes into close contact with almost the entire surface of the circumferential projection by biting into the fleshy portion. Connection structure. 2. A plurality of said circumferential projections are protruded from said connected member at intervals from each other in the axial direction.
A connection structure for an endoscope tube according to any one of the preceding claims. 3. The endoscope tube connection structure according to claim 1, wherein an outer diameter of the flexible tube at a portion connected to the connected member is constant. 4. A rigid connected member having a peripheral projection having a sharp pointed tip formed on an outer peripheral surface is inserted into an end of a flexible tube, and the flexible member is inserted at a portion where the connected member is inserted. By pressing the tube in the radial direction from the outer peripheral surface with a press mold without heating the tube to the softening point, the peripheral protrusions bite into the fleshy portion from the inner peripheral surface of the flexible tube, and the peripheral protrusions A method of connecting a tube for an endoscope, wherein the member to be connected and the flexible tube are connected so that the fleshy portion is in close contact with the entire surface. 5. The endoscope tube according to claim 4, wherein the flexible tube is rotated around an axis relative to a surface of the press die while being pressed by the press die. Connection method. 6. The method for connecting an endoscope tube according to claim 4, wherein an outer diameter of the flexible tube at a portion connected to the connected member is constant.