JP2009219684A - Structure of connection part in endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a connection part in an endoscope, which is capable of maintaining a stable connection state over a long period of time without generating the backlash of a connecting opposite member fixed to a square shaft of an axis member by a nut-like member. <P>SOLUTION: A screw hole 21 is formed in a connecting opposite member 16 parallel to the axis on the outside of the vicinity of the outer peripheral part of the nut-like member 18, and a countersunk screw 22 is tightened into the screw hole 21, and the nut-like member 18 screwed onto a male threaded part 13 of the axis member 11 is pressed directly or indirectly inward on a slope of a head 22a of the countersunk screw 22 screwed into the screw hole 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a structure of a connecting portion employed in a rotation operation mechanism or the like disposed in an operation portion of an endoscope.

In a rotation operation mechanism such as a bending operation mechanism or a treatment instrument raising operation mechanism provided in an operation unit of an endoscope, a substantially polygonal angular shaft portion and a male screw portion are formed on a shaft member, A structure is employed in which a connection partner member in which a square hole that fits into the square shaft portion is formed is fixed to the shaft member by a nut-like member that is screwed with the male screw portion (for example, Patent Documents 1, 2, and 3). 4, 5 etc.).
JP-A-6-327614 JP-A-7-194519 JP-A-9-98942 JP-A-10-286220 JP 2005-160791

  FIG. 7 shows an example of the structure of a connecting portion in a conventional endoscope. A shaft member 90 is formed with a substantially polygonal angular shaft portion 92 adjacent to a male screw portion 91, and is connected to a connecting counterpart member. 93 is formed with a substantially polygonal square hole 94 that fits into the square shaft portion 92, and the connection partner member 93 is engaged with the male thread portion 91 of the shaft member 90 by a nut-like member 95. The shaft member 90 is fixed by being pressed against the step portion 96 formed at the end.

  However, it is unavoidable that there is some backlash in the rotation direction between the square shaft portion 92 and the square hole 94 due to the tolerance of component manufacturing, etc., and due to the presence of such backlash in the rotation direction, a certain period of time is unavoidable. After the elapse of time, the nut-like member 95 is loosened, and there is a tendency that the connection state of the connection partner member 93 with respect to the shaft member 90 is loose.

  Therefore, a structure is adopted in which a screw hole is formed in a position distant from the center of the nut-like member 95 in parallel to the axis, and the tip of the pointed screw screwed into the screw hole is bitten into the surface of the connection counterpart member 93. However, since the backlash of the square hole 94 of the connection partner member 93 with respect to the shaft member 90 cannot be eliminated, the connection partner member 93 often rattles with respect to the shaft member 90 early and late.

  The present invention relates to a structure of a connecting portion in an endoscope that can maintain a stable connection state for a long period of time without causing rattling in a connection counterpart member fixed to a rectangular shaft portion of a shaft member with a nut-like member. The purpose is to provide.

  In order to achieve the above object, the structure of the connecting portion in the endoscope of the present invention is such that a substantially polygonal angular shaft portion and a male screw portion are formed on a shaft member disposed in the endoscope, and the angular shaft portion In the structure of the connecting portion in the endoscope in which the connecting partner member in which the square hole to be fitted is formed is fixed to the shaft member with the nut-like member screwed with the male screw portion, the outer side near the outer peripheral portion of the nut-like member The head of the countersunk screw in which a screw hole is formed in the connecting member parallel to the axis, and the countersunk screw is tightened in the screw hole, and the nut-like member tightened in the male screw part of the shaft member is screwed into the screw hole. It is configured to press directly or indirectly inward on the slope of the part.

  In addition, a slitted washer having a substantially C-shaped planar shape is sandwiched between the head of the countersunk screw and the connection partner member, and the notched washer is pressed against the outer periphery of the nut-like member by the head of the countersunk screw In this case, the inner peripheral surface of the slitted washer may be formed in a slope shape along the slope of the head of the countersunk screw.

  Further, the outer edge portion of the nut-like member may be directly pressed by the slope of the head of the countersunk screw. In that case, the outer periphery of the nut-like member is formed in a sloped shape along the slope of the head of the countersunk screw. May be.

  According to the present invention, a state in which a screw hole is formed in the connection partner member parallel to the axis line on the outer side in the vicinity of the outer peripheral portion of the nut-like member, and a countersunk screw is tightened in the screw hole, and is tightened to the male screw portion of the shaft member By directly or indirectly pressing the nut-like member inwardly on the inclined surface of the head of the countersunk screw screwed into the screw hole, the square shaft portion of the shaft member and the square hole of the connecting counterpart member are Since it is firmly engaged by the reaction, rattling does not occur in the connection partner member fixed to the angular shaft portion of the shaft member with the nut-like member, and a stable connection state can be maintained for a long period of time.

  A substantially polygonal angular shaft portion and a male screw portion are formed on a shaft member arranged in the endoscope, and a connection partner member in which a square hole that fits into the square shaft portion is formed is screwed into the male screw portion. In the structure of the connecting portion in the endoscope fixed to the shaft member by the nut-like member, a screw hole is formed in the connecting counterpart member on the outer side in the vicinity of the outer peripheral portion of the nut-like member in parallel with the axis, and the countersunk screw is formed in the screw hole. Then, the nut-like member that is fastened to the male screw portion of the shaft member is directly or indirectly pressed inward by the inclined surface of the head of the countersunk screw screwed into the screw hole.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 5 shows the entire configuration of the endoscope. The operation portion 2 is connected to the proximal end of the flexible insertion portion 1, and the bending portion formed in the distal end side region of the insertion portion 1. 3 can be bent by an arbitrary angle in an arbitrary direction by rotating the bending operation knob 4 disposed in the operation unit 2.

  A treatment instrument raising piece 5 for controlling the direction of the distal end portion 100a of the treatment instrument 100 passed through the treatment instrument insertion channel is disposed at the most distal end portion of the insertion portion 1. The treatment instrument raising piece 5 is swung by rotating the raising piece operation lever 6 disposed in the operation unit 2 to move the operation wire 7 forward and backward, whereby the direction of the distal end portion 100a of the treatment instrument 100 is changed. Changes.

  FIG. 2 is a side sectional view of the rotation operation mechanism to which the raising piece operation lever 6 is attached, and FIG. 1 is an exploded perspective view thereof. Reference numeral 11 denotes a shaft member that is rotatably disposed around a coaxial line with the bending operation knob 4 in a region surrounding the bending operation mechanism that supports the bending operation knob 4. Although the link member etc. which were connected with the operation wire 7 are connected with the shaft member 11, the illustration is abbreviate | omitted.

  In the region on the head side (upper side in the drawing) of the shaft member 11, an angular shaft portion 12 whose outer surface is substantially polygonal (for example, a square with rounded corners) is formed. A male screw portion 13 is formed in a region near each corner portion, and a step portion 14 having a step surface toward the corner shaft portion 12 side is formed at the base end portion of the corner shaft portion 12.

  Reference numeral 16 denotes a metal plate that is inserted and integrated with the raising piece operating lever 6 when the plastic raising piece operating lever 6 is manufactured by molding, and rotates integrally with the shaft member 11. It is the connection partner member connected so that it may be done.

  A square hole 17 having a substantially polygonal shape (for example, a quadrangle with rounded corners) that fits into the corner shaft portion 12 of the shaft member 11 is formed in the coupling partner member 16 so as to penetrate therethrough. The square shaft portion 12 of the shaft member 11 is fitted into the square hole 17, and the plate surface of the connection partner member 16 around the square hole 17 is in contact with the stepped portion 14 of the shaft member 11. However, it is inevitable that the square hole 17 has some backlash with respect to the square shaft portion 12 due to the dimensional tolerance necessary for manufacturing the component.

  Reference numeral 18 denotes a metal nut-like member in which a female screw 19 that is screwed into the male screw portion 13 of the shaft member 11 is formed in the center portion, and is formed in a disk shape having a constant thickness. It is formed in a circle. Reference numeral 20 denotes a crimp hole for engaging the tip of a tool that rotates the nut-like member 18. The nut-like member 18 is screwed into the male screw portion 13 of the shaft member 11 and presses and fixes the connection partner member 16 to the step portion 14 of the shaft member 11.

  A screw hole 21 is formed in the vicinity of the outer peripheral portion of the connection partner member 16 and outside the vicinity of the outer peripheral portion of the nut-like member 18, and a screw hole 21 is formed in parallel with the axis. A countersunk screw 22 having a diameter 22a that gradually widens conically from the threaded portion side is tightened.

  Between the head 22a of the countersunk screw 22 and the connection partner member 16, a washer 23 with a notch in which a notch 23a is formed so that the planar shape is substantially C-shaped is sandwiched. The inner peripheral portion of the slitted washer 23 is formed in a conical hole shape having a slope along the slope of the head portion 22a of the countersunk screw 22 (however, it may be a straight screw hole having a constant diameter). .

  The cut washer 23 is arranged so that the outer peripheral surface thereof is in contact with the outer peripheral surface of the nut-like member 18. Therefore, when the countersunk screw 22 is tightened into the screw hole 21, the slit washer 23 is elastically deformed into a state where it is expanded in the radial direction by the pressing force received obliquely from the head 22 a of the countersunk screw 22, and FIG. As shown by an arrow A in FIG. 3 illustrating a cross section taken along the line III-III, the nut-like member 18 is pushed toward the inner shaft member 11 side. In this manner, the nut-like member 18 in the state of being fastened to the male screw portion 13 is indirectly pressed inward by the inclined surface of the head portion 22a of the countersunk screw 22 screwed into the screw hole 21.

  Then, due to the reaction, as shown by an arrow B in FIG. 3, the connection partner member 16 is pushed outward in the direction away from the shaft member 11, so that the size of the gap is shown in FIG. 4 illustrating the IV-IV cross section in FIG. 2. As shown in an exaggerated manner, the square hole 17 of the connection partner member 16 is strongly pressed against the plane of the angular shaft portion 12 of the shaft member 11 at the two sides, and the square hole 17 of the connection partner member 16 is It is firmly engaged with the angular shaft portion 12 in a state where no rattling occurs.

  At the stage of assembly work, the nut-like member 18 is in a state immediately before tightening the male screw portion 13 of the shaft member 11 before the countersunk screw 22 is tightened, and the countersunk screw 22 is completely tightened. The nut-shaped member 18 is finally tightened tightly to the male threaded portion 13 of the shaft member 11 after the state where no play is generated between the square shaft portion 12 and the square hole 17.

  As a result, no rattling occurs between the square shaft portion 12 of the shaft member 11 and the square hole 17 of the connecting counterpart member 16 even after a period of time, and therefore the nut-like member 18 does not loosen, and the shaft member 11 And the connection partner member 16 can be stably maintained for a long time without rattling.

  FIG. 6 shows a second embodiment of the present invention, wherein the nut-like member 18 in a state of being fastened to the male screw portion 13 of the shaft member 11 without the cut washer 23 of the first embodiment described above. The outer edge portion is directly pressed inward by the inclined surface of the head portion 22a of the countersunk screw 22 screwed into the screw hole 21.

  The outer peripheral portion 18a of the nut-like member 18 is formed in a conical surface having an inclined surface in the same direction as the inclined surface of the head 22a of the countersunk screw 22 (however, it may be a vertical surface). Other configurations are the same as those of the first embodiment, and the same operational effects as those of the first embodiment can be obtained.

  The present invention is not limited to the above-described embodiments. For example, the present invention is not limited to the operation mechanism for the treatment tool raising piece, but for example, an operation mechanism for optical adjustment such as focusing or zoom, or a bending operation. It may be applied to a mechanism or the like.

It is a disassembled perspective view of the connection part in the endoscope of the 1st example of the present invention. It is side surface sectional drawing of the connection part in the endoscope of 1st Example of this invention. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2 of the first embodiment of the present invention. It is IV-IV sectional drawing in FIG. 2 of 1st Example of this invention. 1 is a side view showing an overall configuration of an endoscope to which the present invention is applied. It is side surface sectional drawing of the connection part in the endoscope of the 2nd Example of this invention. It is side surface sectional drawing of the connection part in the conventional endoscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Shaft member 12 Square shaft part 13 Male thread part 14 Step part 16 Connection partner member 17 Square hole 18 Nut-shaped member 18a Outer part 21 Screw hole 22 Countersunk screw 22a Head 23 Cut washer 23a Cut

Claims (5)

A shaft member disposed in the endoscope is formed with a substantially polygonal angular shaft portion and a male screw portion, and a connection partner member in which a square hole that fits into the square shaft portion is formed is connected to the male screw portion and the screw. In the structure of the connecting portion in the endoscope fixed to the shaft member with a mating nut-like member,
The nut in a state in which a screw hole is formed in the connection counterpart member in the vicinity of the outer periphery of the nut-like member in parallel with the axis, and a countersunk screw is tightened into the screw hole, and the screw is fastened to the male screw portion of the shaft member. A structure of a connecting portion in an endoscope, wherein a member is pressed directly or indirectly inwardly by an inclined surface of a head of the countersunk screw screwed into the screw hole.   A notched washer having a substantially C-shaped planar shape is sandwiched between the head of the countersunk screw and the connecting counterpart member, and the notched washer is the head of the countersunk screw and the outer periphery of the nut-like member The structure of the connecting portion in the endoscope according to claim 1, wherein the connecting portion is pressed against the endoscope.   The structure of the connection part in the endoscope according to claim 2, wherein an inner peripheral surface of the slitted washer is formed in a slope shape along the slope of the head of the countersunk screw.   The structure of the connecting portion in the endoscope according to claim 1, wherein an outer edge portion of the nut-like member is directly pressed by an inclined surface of the head of the countersunk screw.   The structure of the connection part in the endoscope of Claim 4 with which the outer peripheral part of the said nut-shaped member is formed in the inclined surface shape along the inclined surface of the head of the said countersunk screw.

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