JP4731286B2 - Endoscope pipe connection structure - Google Patents

Description

  The present invention relates to a structure of a pipe connecting portion of an endoscope for connecting and fixing an end portion of a flexible tube provided in the endoscope to allow passage of fluid to a hard pipe.

  In the endoscope, various fluid conduits for air supply, water supply, suction, and the like are provided, and an operation valve thereof is disposed in the operation unit. The fluid conduit is formed of a flexible tube in the insertion part of the endoscope, but cannot be directly connected to the cylinder of the operation valve. It comes to connect.

  However, since a force for pulling the flexible tube, fluid pressure, or the like is applied to such a connection portion, the flexible tube and the metal pipe are prevented from being pulled out by such a force. It is necessary to fix firmly.

Therefore, conventionally, for example, as shown in FIG. 9, a protrusion 4 is formed on the outer peripheral surface near the end of the hard pipe 1, and the flexible tube 2 is hardened beyond the protrusion 4 from the end of the hard pipe 1. The flexible tube 2 is fixed to the projection 4 from the outer peripheral side by the tube fixing ring 3 that is put on the pipe 1 and fitted on the outer peripheral portion of the flexible tube 2 (for example, Patent Document 1). .
JP-A-9-299321

  However, in the structure of the pipe connection part of the conventional endoscope having the above-described configuration, the tube pressing part 31 for pressing the flexible tube 2 from the outer peripheral side is tapered to one end side of the tube fixing ring 3. Only a hole-like slope is formed.

  Therefore, for example, when a force in the direction opposite to the pulling direction of the flexible tube 2 (X direction) acts on the tube fixing ring 3, the pressing force of the flexible tube 2 by the tube fixing ring 3 becomes extremely small. As shown in FIG. 10, when a force F in the pulling direction is applied to the flexible tube 2 next time, the flexible tube 2 can be removed from the connection portion relatively easily or even if it does not come off. May occur.

  Even when no force in the X direction is applied to the tube fixing ring 3, the flexible tube 2 is formed with a configuration in which a tapered inclined surface is formed on one end side of the tube fixing ring 3 as the tube pressing portion 31. Since it cannot be pressed with a large force, there may be a case where a fixing force sufficient to counter the force F in the pulling direction cannot be obtained.

  Further, in the structure of the pipe connection portion of the conventional endoscope as shown in FIG. 9, the inner peripheral surface of the tube fixing ring 3 is pressed into the outer peripheral surface of the metal pipe 1 at a portion behind the tube pressing portion 31. It is necessary to be in perfect contact, and as shown in FIG. 11, if there is a gap A between the inner peripheral surface of the tube fixing ring 3 and the outer peripheral surface of the flexible tube 2, the tube fixing ring 3 is It moves easily in the X direction and the flexible tube 2 comes off or fluid leakage occurs.

  Moreover, whether or not such a gap A is formed largely depends on the influence of the thickness of the flexible tube 2, and it is the manufacturing that a certain variation (tolerance) occurs in the thickness of the flexible tube 2. It is unavoidable.

  Therefore, a large variation occurs in the connection strength of the flexible tube 2 to the metal pipe 1 and, as shown in FIG. 12, when the thickness of the flexible tube 2 varies toward the thicker side, the flexible tube 2 Since the tube fixing ring 3 cannot be fitted to the tube, it becomes impossible to assemble. In such a case, the inner diameter of the tube fixing ring 3 is trimmed to match the outer diameter of the flexible tube 2 at the assembly site. The manufacturing process will be confused.

  Therefore, the present invention provides a structure of an endoscope pipe connection portion that can firmly and securely connect and fix an end portion of a flexible tube provided in an endoscope to allow fluid to pass through to a hard pipe. Endoscope pipe connection structure that can be securely and easily fixed to a hard pipe without being affected by variations in the thickness of the flexible tube. The purpose is to provide.

  In order to achieve the above object, the structure of the pipe connection portion of the endoscope of the present invention is for connecting and fixing the end portion of the flexible tube provided in the endoscope to the rigid pipe so as to allow fluid to pass therethrough. A structure of a pipe connection part of an endoscope, in which a protrusion is formed on the outer peripheral surface near the end of the hard pipe, and the flexible tube is placed over the hard pipe over the protrusion from the end of the hard pipe. In the structure of the pipe connection part of the endoscope in which the tube fixing ring fitted on the outer peripheral part of the flexible tube is attached to the protruding part from the outer peripheral side of the flexible tube, A pair of front and rear tube pressing portions for pressing the flexible tube to the front outer edge portion and the rear outer edge portion of the protrusion are formed on the inner peripheral surface.

  It should be noted that the inner peripheral surface of the tube fixing ring is formed at a diameter that does not press the outer peripheral surface of the portion covering the protruding portion of the flexible tube in the portion located between the pair of front and rear tube pressing portions. Good.

  A gap is formed between the inner peripheral surface of the tube fixing ring and the outer peripheral surface of the portion of the flexible tube that covers the hard pipe between the one end of the tube fixing ring and the tube pressing portion. The inner diameter of the tube fixing ring is preferably formed in a tapered hole shape that gradually spreads toward the end between the other end of the tube fixing ring and the tube pressing part. It may be.

  In addition, one or both of the pair of tube pressing portions may be formed by a step difference in which the inner diameter of the tube fixing ring is vertically changed, or formed by a tapered surface in which the inner diameter of the tube fixing ring is gradually changed. It may be.

  If a plurality of slits are formed in parallel in the axial direction from the end of the tube fixing ring that covers the flexible tube to the position beyond the pair of tube pressing parts, the tube fixing ring can be easily attached and detached. Become.

  According to the present invention, a pair of front and rear tube pressing portions for pressing the flexible tube against the front outer edge portion and the rear outer edge portion of the protrusion are formed on the inner peripheral surface of the tube fixing ring. The end of the flexible tube provided in the endoscope to pass through can be firmly and securely connected and fixed to the hard pipe, and the inner peripheral surface of the tube fixing ring is a portion other than the pair of tube pressing portions. With a diameter that allows a gap to be formed between the flexible tube and the outer peripheral surface of the flexible tube, even if there is a variation in the thickness of the flexible tube, the rigid pipe can be reliably and easily affected without any influence. Can be fixed to the connection.

  A structure of a pipe connecting portion of an endoscope for connecting and fixing an end portion of a flexible tube provided in the endoscope to allow passage of fluid to a hard pipe, and an outer peripheral surface in the vicinity of the end portion of the hard pipe The flexible tube is covered with the hard pipe over the protrusion from the end of the rigid pipe, and the tube fixing ring fitted on the outer periphery of the flexible tube attaches the flexible tube. In the structure of the pipe connection part of the endoscope attached so as to be pressed from the outer peripheral side to the projection part, the flexible tube is connected to the front outer edge part and the rear outer edge part of the projection on the inner peripheral surface of the tube fixing ring. A portion where a pair of front and rear tube pressing portions for pressing each is formed, and an inner peripheral surface of the tube fixing ring is covered with a protruding portion of the flexible tube at a portion located between the pair of front and rear tube pressing portions. Formed with a diameter that does not press the outer peripheral surface of In between the one end and the tube press portion of the tube fixing ring is formed in diameter that can be a gap between the outer peripheral surface of the portion overlying the rigid pipe of the flexible tube.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 3 schematically shows a piping configuration of an endoscope, and a flexible tube 2 for allowing fluid to pass is an air / water supply operation valve 11, a suction operation valve 12, and a treatment disposed in an operation unit of the endoscope. The tube fixing ring 3 is attached to the metal pipe 1 so as to press and fix the flexible tube 2 to the metal pipe 1.

  FIG. 1 is a longitudinal sectional view of a connecting portion of the flexible tube 2 to such a metal pipe 1, and FIG. 2 is an external perspective view. The metal pipe 1 is formed of, for example, a stainless steel pipe, and the flexible tube 2 having an inner diameter smaller than the outer diameter of the metal pipe 1 is formed of, for example, a tetrafluoroethylene resin tube. However, the metal pipe 1 and the flexible tube 2 may be made of other materials. The inner diameter of the flexible tube 2 may be the same as or slightly larger than the outer diameter of the metal pipe 1.

  On the outer peripheral surface in the vicinity of the end of the metal pipe 1, protrusions 4 having a constant height are uniformly formed over the entire periphery. The protrusion 4 can be easily formed by fixing a metal pipe material having a diameter one size larger than that of the metal pipe 1 to the outer surface of the metal pipe 1 by welding or brazing. However, the protrusion 4 may be formed integrally with the metal pipe 1 or may be divided into a plurality of parts in the circumferential direction.

  The flexible tube 2 is put on the metal pipe 1 in a state of overcoming the protrusion 4 from the opening end side of the metal pipe 1, and a tube fixing ring fitted on the outer peripheral portion of the flexible tube 2 at that portion. 3 is attached in the state which presses the flexible tube 2 to the protrusion 4 part from the outer peripheral side.

  The tube fixing ring 3 is formed in a substantially cylindrical shape as a whole, and is attached by sliding from the metal pipe 1 side (that is, from above in FIGS. 1 and 2). In the following description, the upper metal pipe 1 side is referred to as the rear, and the lower flexible tube 2 side is referred to as the front.

  The shape of the inner peripheral surface of the tube fixing ring 3 has been devised in detail to firmly connect and fix the flexible tube 2 to the metal pipe 1, so that the flexible tube 2 gets over the protrusion 4. In the covered portion, the inner peripheral surface (bag-shaped relief portion 30) of the tube fixing ring 3 is formed to have a swelled diameter so as not to press the outer peripheral surface of the flexible tube 2.

  A rear tube pressing portion 31 that presses the flexible tube 2 against the rear outer edge portion 41 of the protrusion 4 is formed at the rear end portion of the bag-shaped escape portion 30. The rear tube pressing portion 31 of this embodiment is formed in a tapered shape with a diameter gradually increasing toward the bag-shaped relief portion 30 side, and the flexible tube 2 is pressed and fixed to the rear outer edge portion 41 from the oblique rear side by the surface portion. It has the same shape and function as a conventional tube pressing part.

  A front tube pressing portion 32 that presses the flexible tube 2 against the front outer edge portion 42 of the protrusion 4 is formed at the front end portion of the bag-shaped relief portion 30. The front tube pressing portion 32 of this embodiment is formed by a step in which the inner diameter of the tube fixing ring 3 is vertically reduced at that portion, and the flexible tube 2 is inclined to the front outer edge portion 42 from the diagonally forward side. The part is pressed and fixed.

  With such a configuration, even if a force in the X direction acts on the tube fixing ring 3, the tube fixing ring 3 does not move relative to the flexible tube 2, and the front tube pressing portion 32 projects the flexible tube 2. 4 is strongly pressed and fixed to the front outer edge portion 42, so that the pressing force of the rear tube pressing portion 31 against the flexible tube 2 is greatly increased as compared with the conventional case.

  As a result, the flexible tube 2 is firmly connected and fixed to the end portion of the metal pipe 1, and the flexible tube 2 is pulled in the direction of pulling out from the inside of the tube fixing ring 3 (the direction opposite to the X direction). Even if the force F acts, the flexible tube 2 does not come off or fluid leaks. In addition, about the pulling-out at the time of pulling the flexible tube 2 straight, the yield strength about twice as much as the prior art was obtained.

  The inner peripheral surface of the tube fixing ring 3 has a diameter that allows a gap between the outer peripheral surface of the flexible tube 2 covering the metal pipe 1 at a portion other than the rear tube pressing portion 31 and the front tube pressing portion 32. The portion where the inner peripheral surface 33 of the tube fixing ring 3 covers the metal pipe 1 of the flexible tube 2 between the rear tube pressing portion 31 and the rear end portion of the tube fixing ring 3. It is formed in a diameter that allows a certain gap A to be formed between the outer peripheral surface and the outer peripheral surface.

  Further, between the front tube pressing portion 32 and the front end portion of the tube fixing ring 3, an inner peripheral surface 34 of the tube fixing ring 3 is formed in a tapered surface shape that gradually spreads toward the tip end side. Therefore, when the tube fixing ring 3 is slid and attached to the flexible tube 2 placed on the end portion of the metal pipe 1, the flexible tube 2 is easily guided into the tube fixing ring 3, and assembly work is performed. Can be easily performed.

  In this way, the inner peripheral surface of the tube fixing ring 3 is formed to have a diameter that allows a gap to be formed between the outer peripheral surface of the flexible tube 2 at portions other than the pair of tube pressing portions 31 and 32. Even if the flexible tube 2 varies on the thick side, there is no problem in assembly.

  Further, even if the flexible tube 2 varies on the thin side, the tube fixing ring 3 presses the flexible tube 2 against the projection 4 from both the front and rear directions by the rear tube pressing portion 31 and the front tube pressing portion 32. As a result, the tube fixing ring 3 is not rattled or loosened, and a strong connection strength can be obtained.

  In addition, this invention is not limited to the said Example, For example, like the 2nd and 3rd Example shown by FIG.4 and FIG.5, the rear side tube press part 31 and the front side tube press part 32 are shown. Each may be formed of either a step or a tapered surface.

  Further, as in the fourth embodiment shown in FIG. 6, the axial direction from the end of the tube fixing ring 3 on the side covered with the flexible tube 2 to the position beyond the pair of tube pressing portions 31, 32. A plurality of slits 35 may be formed in parallel.

  By providing such a slit 35, as shown in FIG. 7, the operation of the front tube pressing portion 32 overcoming the portion covered with the projection 4 of the flexible tube 2 in the operation of attaching and detaching the tube fixing ring 3 is performed. At this time, the tube fixing ring 3 can be easily elastically deformed in the spreading direction so that the operation can be performed very smoothly.

  In carrying out the present invention, as in the fifth embodiment shown in FIG. 8, the tube fixing ring 3 is attached and detached from the flexible tube 2 side opposite to that in the first embodiment. May be. In this case, the tube fixing rings 3 of the first to fourth embodiments can be used as they are simply by reversing the directions.

  In addition, the tube fixing ring 3 used in the present invention can be used as a replacement part of a portion where the conventional tube fixing ring is used, so that the periodic inspection of endoscopes already used in the market can be performed. In this case, the connection strength can be greatly improved by exchanging only the tube fixing ring 3.

  The present invention is not limited to the connection portion of the flexible tube 2 to the metal pipe 1 in the operation portion of the endoscope, but the end portion of the flexible tube 2 for allowing fluid to pass is connected and fixed to the metal pipe 1. The present invention can also be applied to a connector portion and other portions, and may be a portion in which a hard plastic pipe or the like is used instead of the metal pipe 1.

It is a longitudinal cross-sectional view of the pipe connection part of the endoscope of the first embodiment of the present invention. It is a perspective view of the piping connection part of the endoscope of the 1st example of the present invention. It is a piping schematic diagram of an endoscope to which the present invention is applied. It is a longitudinal cross-sectional view of the pipe connection part of the endoscope of the second embodiment of the present invention. It is a longitudinal cross-sectional view of the piping connection part of the endoscope of the 3rd Example of the present invention. It is a perspective view of the tube fixing ring of the piping connection part of the endoscope of the 4th example of the present invention. It is a longitudinal cross-sectional view of the state in the middle of the assembly process of the piping connection part of the endoscope of the 4th Example of the present invention. It is a longitudinal cross-sectional view of the piping connection part of the endoscope of the 5th Example of this invention. It is a longitudinal cross-sectional view of the piping connection part of the conventional endoscope. It is a longitudinal cross-sectional view for demonstrating operation | movement of the piping connection part of the conventional endoscope. It is a longitudinal cross-sectional view for demonstrating the problem of the piping connection part of the conventional endoscope. It is a longitudinal cross-sectional view for demonstrating the problem of the piping connection part of the conventional endoscope.

Explanation of symbols

1 Metal pipe (hard pipe)
2 Flexible tube 3 Tube fixing ring 4 Protrusion 30 Bag-shaped escape portion 31 Rear tube pressing portion 32 Front tube pressing portion 33 Inner peripheral surface (constant diameter)
34 Inner peripheral surface (tapered surface)
35 Slot 41 Rear outer edge 42 Front outer edge A Clearance

Claims (6)

A structure of a pipe connecting portion of an endoscope for connecting and fixing an end portion of a flexible tube provided in the endoscope to allow fluid to pass through to a hard pipe,
A protrusion is formed on the outer peripheral surface near the end of the hard pipe, and the flexible tube is put on the hard pipe beyond the protrusion from the end of the hard pipe, and the outer periphery of the flexible tube In the structure of the pipe connection part of the endoscope attached in a state in which the tube fixing ring fitted to the part presses the flexible tube from the outer peripheral side to the protruding portion,
A pair of front and rear tube pressing portions for pressing the flexible tube against the front outer edge portion and the rear outer edge portion of the protrusion are formed on the inner peripheral surface of the tube fixing ring, and the tube fixing ring A pipe connection of an endoscope , wherein a plurality of slits are formed in parallel in an axial direction from an end portion of the flexible tube to a position exceeding the pair of tube pressing portions. Part structure.   The inner peripheral surface of the tube fixing ring is formed at a diameter that does not press the outer peripheral surface of the portion covering the protruding portion of the flexible tube at a portion located between the pair of front and rear tube pressing portions. The structure of the pipe connection part of the endoscope according to claim 1.   The inner peripheral surface of the tube fixing ring is between the one end portion of the tube fixing ring and the outer surface of the portion of the flexible tube that covers the hard pipe. The structure of the pipe connection part of the endoscope according to claim 2, wherein the structure is formed to have a diameter in which a gap is formed.   The inner peripheral surface of the tube fixing ring is formed in a tapered hole shape that gradually spreads toward the other end portion between the other end portion of the tube fixing ring and the tube pressing portion. Structure of the pipe connection part of the described endoscope.   The pipe connection part of the endoscope according to any one of claims 1 to 4, wherein one or both of the pair of tube pressing parts is formed by a step difference in which an inner diameter of the tube fixing ring is vertically changed. Structure.   The pipe connection part of the endoscope according to any one of claims 1 to 4, wherein one or both of the pair of tube pressing parts is formed by a tapered surface in which an inner diameter of the tube fixing ring is gradually changed. Structure.

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