JP2010264040A - Zoom endoscope - Google Patents

Abstract

[PROBLEMS] To ensure flexibility and excellent rotational followability required in each of a curved portion and a flexible tube portion without connecting guide tubes (thus, without thickening an insertion portion of an endoscope). To provide a zoom endoscope that can obtain a zooming operation without a sense of incongruity by a smooth rotation transmission action even when bent.
A rotation transmission wire 9 is formed by integrally connecting a base-side hard torque wire 9W and a tip-side soft torque coil 9C having the same outer diameter size in series, and is made of a twisted wire. The core wire 9x of the wire 9W is pulled out from the hard torque wire 9W and inserted into the hollow central shaft portion of the soft torque coil 9C, and in this state, is joined and fixed to the soft torque coil 9C.
[Selection] Figure 1

Description

  The present invention relates to a zoom endoscope having a zoom optical system built in an observation window.

  In a zoom endoscope using a zoom optical system with a variable focal length as an objective optical system, it is connected to the proximal end of the insertion section in a flexible guide tube arranged over the entire length of the flexible insertion section. A flexible rotation transmission wire that is rotated from the operated portion side is inserted so as to be rotatable around the axis.

  Then, when the tip of the rotation transmission wire is connected to a zoom operation mechanism or the like that is rotatably arranged in the tip of the insertion portion, and the rotation transmission wire is operated to rotate around the axis by a motor drive or manual operation from the operation unit side, The zoom operation mechanism at the tip is operated via a rotation transmission wire, and the focal length of the zoom optical system is changed (for example, Patent Documents 1 and 2).

JP-A-2005-287576 JP 2002-65579 A

  The rotation transmission wire used for the zooming operation must have the characteristic of smoothly transmitting the rotation on the proximal end side to the distal end side while bending inside the endoscope insertion portion as it bends. is there.

  However, the insertion portion of the endoscope is configured such that a bending portion that bends with a small radius of curvature by remote control is connected to the distal end of a flexible tube portion that freely bends along the space shape in the body cavity, etc. It is necessary to make the characteristics of the rotation transmission wire different between the inside and the inside of the flexible tube.

  That is, the rotation transmission wire material is important to be flexible so that rotation can be transmitted without great resistance even if it is bent with a small radius of curvature in the curved portion. However, in a flexible tube part that is much longer than a curved part and is not bent with a smaller radius of curvature, if the rotation transmission wire is weak, rotation followability decreases due to the occurrence of wavy sag, etc. It is important not to be too flexible.

  Therefore, in the conventional invention described in Patent Documents 1 and 2, etc., a soft torque coil that is flexible and has good rotation followability is used in the curved portion, and a harder torque is applied to the portion located in the flexible tube portion. Both torque coils were connected using a coil. In the connecting portion, rod-like connecting members are inserted into both torque coils and fixed to each other.

  However, in such a configuration in which the soft and hard torque coils are connected in series, the flexibility cannot be greatly changed unless the two torque coils have different diameters. For this reason, the clearance between the torque coil and the guide tube is increased in the soft part and the rotational followability is reduced (Patent Document 1), or a guide tube having a different diameter is connected. The outer diameter of the insertion portion has become thick, and the insertion property of the endoscope has therefore been reduced (Patent Document 2).

  In addition, since a rod-shaped connecting member that is inserted into both of the connecting portions that connect the two torque coils in series is used, the length of the hard portion of the connecting portion increases, so that a large rotation occurs in that portion when bent. In some cases, resistance was generated, causing malfunction.

  According to the present invention, in the bending portion and the flexible tube portion, the necessary flexibility and excellent rotational followability can be obtained without connecting the guide tubes (thus, without making the insertion portion of the endoscope thick). An object of the present invention is to provide a zoom endoscope that can be ensured and can obtain a zooming operation without a sense of incongruity by a smooth rotation transmission action even when bent.

  In order to achieve the above object, the zoom endoscope of the endoscope of the present invention has a zoom optical system disposed in an observation window disposed at the distal end of a flexible insertion portion, A flexible rotation transmission wire that is rotated from the operation unit side connected to the base end of the insertion portion is inserted into a flexible guide tube that is disposed over substantially the entire length so as to be rotatable in the direction around the axis. The tip of the rotation transmission wire is connected to the zoom operation mechanism disposed in the tip of the unit, and the rotation transmission wire is rotated in the direction around the axis from the operation unit side, so that the zoom operation mechanism operates and the zoom optical system In the zoom endoscope configured so that the focal length of the rotation is changed, the rotation transmission wire includes a base-side hard torque wire formed by twisting a plurality of strands around one core wire, Wire outside the same diameter as the hard torque wire It is formed by tightly winding on a constant diameter of the size, and is formed by connecting in series with a soft torque coil on the tip side where the central shaft portion is hollow, and the core wire of the hard torque wire is pulled out from the hard torque wire It is inserted into the hollow central shaft portion of the soft torque coil and bonded and fixed to the soft torque coil in this state.

  A bending portion that is bent by a remote operation from the operation portion is provided at the distal end portion of the insertion portion, and the soft torque coil is disposed in a region located within the bending portion, and the hard torque wire is positioned outside the bending portion. The soft torque coil may be configured by overlapping a plurality of coils having different diameters and winding directions in the radial direction.

  According to the present invention, the rotation transmission wire is formed by integrally connecting a base-side hard torque wire and a tip-side soft torque coil of the same outer diameter in series, and is formed of a stranded wire. The core wire is pulled out from the hard torque wire and inserted into the hollow central shaft portion of the soft torque coil. In this state, the core wire is bonded and fixed to the soft torque coil. Flexibility and excellent rotation follow-up without connecting the guide tubes (thus, without thickening the insertion part of the endoscope), and smooth rotation transmission even when bent Therefore, it is possible to obtain a zooming operation without any sense of incongruity.

It is side surface sectional drawing of the state in which the rotation transmission wire used for the zoom endoscope of the Example of this invention was penetrated in the flexible guide pipe | tube. 1 is an overall configuration diagram of a zoom endoscope according to an embodiment of the present invention. It is sectional drawing in a cross section perpendicular | vertical to the axis line of the rotation transmission wire used for the zoom endoscope of the Example of this invention. It is side surface sectional drawing which decomposes | disassembles and shows the connection part of the rotation transmission wire used for the zoom endoscope of the Example of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 2 shows the overall configuration of the zoom endoscope, and an operation unit 2 for performing various operations is connected to the base end of the flexible insertion unit 1.

  The insertion portion 1 is configured by connecting a bending portion 3 that is shorter than the flexible tube portion 1A and bent by remote operation to the distal end of an elongated and long flexible tube portion 1A, and is arranged in the operation portion 2. By rotating the knob 4, the bending portion 3 can be bent in an arbitrary direction by an arbitrary angle as indicated by a two-dot chain line.

  A zoom optical system 6 having a variable focal length is incorporated as an objective optical system in the back of the observation window 5 arranged on the most distal surface of the insertion unit 1, and an observation image signal picked up there is stored in the insertion unit 1. The signal is transmitted through a flexible signal cable 7 that is inserted through the cable.

  Reference numeral 8 denotes a known zoom operation mechanism attached to the zoom optical system 6 in order to change the focal length of the zoom optical system 6. The zoom operation mechanism 8 is connected to the distal end of a flexible rotation transmission wire 9 inserted and arranged in the insertion portion 1, and the zoom operation mechanism 8 is rotationally driven by the rotation transmission wire 9.

  The rotation transmission wire 9 excellent in rotation transmission is inserted and arranged in a flexible guide tube 10 arranged substantially over the entire length in the insertion portion 1 so as to be rotatable around the axis. The proximal end of the flexible guide tube 10 is fixed in the operation unit 2, and the distal end is connected to a fixed frame or the like of the zoom operation mechanism 8.

  A drive motor 11 for rotating the rotation transmission wire 9 from the base end side is disposed in the operation unit 2, and when the drive motor 11 rotates, the rotation motion is transmitted via the rotation transmission wire 9 to the zoom operation mechanism. 8 is transmitted.

  When the zoom operation mechanism 8 is rotationally driven, so-called zooming is performed in which the focal length of the zoom optical system 6 changes and the observation magnification changes. Reference numeral 12 denotes a zoom operation member provided in the operation unit 2 for switching the drive motor 11 between a stopped state and a rotating state in an arbitrary direction.

  FIG. 1 shows a state in which the rotation transmission wire 9 is loosely inserted in the flexible guide tube 10. The rotation transmission wire 9 is formed by twisting a plurality of strands, and a proximal end-side hard torque wire 9W made of a strand wire having a single core wire 9x at the center shaft portion, and the strands of the hard transmission wire 9W. The soft torque coil 9 </ b> C on the distal end side, which is formed by tightly winding around a constant diameter of the same outer diameter size as that of the outer diameter, and whose central shaft portion is hollow, is integrally formed in series. Both the hard torque wire 9W and the soft torque coil 9C have excellent rotation transmission characteristics.

  In this embodiment, the hard torque wire 9W formed by twisting a strand made of a stainless steel wire or the like is, as shown in FIG. 3 which is a cross-sectional view in a cross section perpendicular to the axis, This is a so-called 1 × 7 stranded wire in which six strands are twisted around the core wire 9x.

  On the other hand, the soft torque coil 9C using a strand made of stainless steel wire or the like that is much thinner than the strand of the hard torque wire 9W is configured by overlapping a plurality of coils having different diameters and winding directions in the radial direction. The central shaft portion is hollow.

  The soft torque coil 9C of this embodiment is formed by a triple coil as shown in FIG. 1, and the inner diameter size (that is, the inner diameter of the hollow portion) of the core wire 9x of the hard torque wire 9W is almost perfect (or slightly It is set to a dimension that is loosely inserted).

  As described above, the hard side and the soft side of the rotation transmission wire 9 are configured by combining the hard torque wire 9W made of a stranded wire and the soft torque coil 9C made of a multi-layer coil. Can be realized with the same outer diameter.

  In the connecting portion between the hard torque wire 9W and the soft torque coil 9C, the core wire 9x is drawn straight from the tip of the hard torque wire 9W, as shown in FIG.

  Then, as shown in FIG. 1, the core wire 9x is inserted straight into the hollow central shaft portion of the soft torque coil 9C, and in this state is soldered to the soft torque coil 9C, silver brazed, or other joining means. As a result, the hard torque wire 9W and the soft torque coil 9C are integrally connected.

  Accordingly, the length of the hard portion of the connecting portion between the hard portion and the soft portion of the rotation transmission wire 9 can be made much shorter than before, and as a result, extra resistance is generated at the connecting portion during bending with respect to rotational motion. Therefore, good rotation transmission can be obtained.

  In the rotation transmission wire 9 having the configuration in which the hard torque wire 9W and the soft torque coil 9C are connected in this way, all the regions located in the bending portion 3 are the soft torque coil 9C, and the hard torque wire 9W. Is disposed only in a region located outside the bending portion 3 (that is, inside the flexible tube portion 1A).

  Therefore, the rotation transmission wire 9 of the present invention can obtain the necessary flexibility and excellent rotational followability in the bending portion 3 and the flexible tube portion 1A, and the hard torque wire 9W and the soft torque coil. Since 9C has the same outer diameter size, it can be inserted into one flexible guide tube 10 with an optimum clearance.

  As such, in the present invention, excellent rotational transmission can be obtained without joining the flexible guide tubes 10 (and thus without increasing the thickness of the insertion portion 1). The zoom optical system 6 can perform a zooming operation without a sense of incongruity due to a smooth rotation transmission action.

DESCRIPTION OF SYMBOLS 1 Insertion part 1A Flexible tube part 2 Operation part 3 Bending part 5 Observation window 6 Zoom optical system 8 Zoom operation mechanism 9 Rotation transmission wire 9C Soft torque coil 9W Hard torque wire 9x Core wire 10 Flexible guide pipe

Claims (3)

A zoom optical system is disposed in the observation window disposed at the distal end of the insertion portion having flexibility, and the proximal end of the insertion portion is disposed in the flexible guide tube disposed substantially over the entire length of the insertion portion. A flexible rotation transmission wire that is rotationally operated from the connected operation unit side is rotatably inserted in the direction around the axis, and the distal end of the rotation transmission wire is inserted into a zoom operation mechanism disposed in the distal end of the insertion unit. The zoom transmission mechanism is operated to change the focal length of the zoom optical system when the rotation transmission wire is rotated in the direction around the axis line from the operation unit side. In the endoscope,
The rotation transmission wire is composed of a base-side hard torque wire formed by twisting a plurality of strands around a single core wire, and the strand has a constant outer diameter size equal to the outer diameter of the hard torque wire. It is formed by tightly winding to the diameter of the soft torque coil on the distal end side in which the central shaft portion is hollow, and the core wire of the hard torque wire is drawn out from the hard torque wire and A zoom endoscope, wherein the zoom endoscope is inserted into a hollow central shaft portion of a soft torque coil and bonded and fixed to the soft torque coil in that state.   A bending portion that is bent by a remote operation from the operation portion is provided at a distal end side portion of the insertion portion, the soft torque coil is disposed in a region located in the bending portion, and the hard torque wire is bent. The zoom endoscope according to claim 1, wherein the zoom endoscope is disposed only in a region located outside the unit.   The zoom endoscope according to claim 1, wherein the soft torque coil is configured by overlapping a plurality of coils having different diameters and winding directions in the radial direction.

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