JPH0882749A - Curvature operation device for endoscope - Google Patents

Abstract

PURPOSE: To provide a curvature operation device for an endoscope capable of obtaining a long life without generating stress concentration in an operation wire in the curvature operation device for the endoscope winding the operation wire around a pulley by one revolution or above. CONSTITUTION: A step 14 of which depth is nearly equal to the thickness of the operation wire 7 is formed on the bottom surface 12 of the groove 11 of the pulley 10, and both sides of the bottom surface part adjacent to the step 14 are formed to curved surface shapes smoothly continuing respectively also, and when the operation wire 7 is wound around the groove 11 by one revolution or above, the operation wire 7 is wound smoothly onto the operation wire 7 of first revolution from the bottom surface 12 of the groove 11 without that the operation wire 7 floats on a position shifting from the first revolution to second revolution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending operation device for an endoscope.

[0002]

2. Description of the Related Art Rotating pulleys are widely used to pull a bending operation wire of an endoscope. In such an endoscope bending operation device, conventionally, an operation wire is wound along the bottom surface of the circumferential groove formed on the outer peripheral surface of the pulley that is rotationally operated, and the proximal end of the operation wire is It is inserted into the hole formed on the bottom surface of the circumferential groove and fixed to the pulley there.

[0003]

In the bending operation device for an endoscope as described above, since the operation wire is wound along the bottom surface of the circumferential groove of the pulley, the operation wire is bent smoothly. Unreasonable force is not added.

However, when the amount of pulling of the operation wire is long and it is necessary to wind the operation wire in the circumferential groove for one rotation or more, the winding of the operation wire is performed at the position where the first rotation turns to the second rotation. Moves from the bottom surface of the circumferential groove to the operation wire of the first round, so that the operation wire is lifted from the bottom surface of the circumferential groove and there is no support on the inside.

Therefore, the operation wire for the second turn is locally deformed at the position where it begins to be wound on the operation wire for the first turn,
As a result, stress concentrates there, causing the operation wire to break in a relatively short period of use.

In view of this, the present invention provides a bending operation device for an endoscope in which an operation wire is wound around a pulley more than once, and the operation wire is free from stress concentration and can have a long life. An object of the present invention is to provide a bending operation device.

[0007]

In order to achieve the above object, the bending operation apparatus for an endoscope according to the present invention is operated along the bottom surface of a groove formed by being recessed from the outer peripheral surface of a pulley that is rotationally operated. In a bending operation device for an endoscope in which a wire is wound and the base end of the operation wire is inserted into a hole portion formed in the bottom surface of the groove and fixed to the pulley there, in the hole position, the bottom surface of the groove A step having a depth approximately equal to the thickness of the operating wire is formed, and a bottom surface portion adjacent to the step is formed into a smoothly continuous curved surface on both sides. It is characterized in that the operation wire is smoothly wound from the bottom surface of the groove onto the operation wire for the first rotation at a position where the operation wire moves from the first rotation to the second rotation when it is wound. And

[0008]

Embodiments will be described with reference to the drawings. FIG. 3 shows an endoscope, in which a flexible bending portion 2 is connected to a distal end of a flexible insertion portion 1, and a distal end portion main body 3 including an objective optical system and the like is further attached to the distal end thereof. It is connected.

The operation portion 4 connected to the proximal end side of the insertion portion 1 is provided with a bending operation knob 6 or the like which is rotated, and a pulley 10 rotatably provided in the operation portion 4.
Is driven to rotate by the bending operation knob 6.

The proximal ends of the pair of operation wires 7, 7 having the distal ends attached to the distal ends of the bending portions 2 are wound around the groove formed in the pulley 10, and the bending operation knob 6 is moved. By rotating and rotating the pulley 10, one operation wire 7 is pulled and at the same time the other operation wire 7 is sent out, whereby the bending portion 2 is bent at an arbitrary angle.

As the operating wire 7, a stranded wire formed by twisting a large number of thin stainless steel wires is used, and a synthetic resin coating or coating for preventing abrasion of the wire is applied to the stranded wire, so that durability is improved. Has been elevated.

FIG. 2 is a side view of the pulley 10. Two grooves 11, 11 for independently winding a pair of operation wires 7, 7 are formed side by side and are recessed from the outer peripheral surface. . Reference numerals 12 and 12 denote bottom surfaces of the grooves 11 and 11.

As shown in FIG. 2, the grooves 11, 11
Are formed eccentrically with respect to the pulley 10,
When the operation wires 7, 7 are pulled to the maximum, that is, when the bending portion 2 is bent to the maximum extent, the winding radius of the operation wires 7, 7 is minimized so that the force required for the bending operation does not become heavy. It has become.

FIG. 1 shows the bottom surface 12 of the groove 11 of the pulley 10.
The pulley 10 is shown in a state of being cut at one groove 11 so that the shape and the winding of the operation wire 7 around it are shown. The cross-sectional shape of the other groove 11 is symmetrical to this.

The operating wire 7 is wound along the bottom surface 12 of the groove 11, and the base end 7a of the operating wire 7 is bent inward at the position of the hole 13 formed in the bottom surface 12 of the groove 11. , And is fixed to the pulley 10 by silver brazing or the like.

At the position of the hole 13, a step 14 having a depth A substantially equal to the thickness of the operating wire 7 is formed on the bottom surface 12 of the groove 11, and the bottom surface 1 adjacent to the step 14 is formed.
2 is formed in a curved surface shape that is smoothly continuous on both sides.

In this embodiment, the bottom surface 12 is first formed in a perfect circle shape, and one step 14 adjacent to the step 14 is deeply machined by a depth A to finish a smooth curved surface.
However, the bottom surface 12 may be formed in a spiral shape so that the depth of the bottom surface 12 shifts by A in one round.

As a result, as shown in FIG. 1, when the operating wire 7 is wound around the groove 11 for one rotation or more, the operating wire 7 is lifted at the position where the first rotation is changed to the second rotation. Instead, it is smoothly wound from the bottom surface 12 of the groove 11 onto the operation wire 7 for the first rotation.

Therefore, even at a position where the operation wire 7 shifts from the first rotation to the second rotation, the operation wire 7 is not locally deformed and stress concentration does not occur during the pulling operation.

[0020]

According to the present invention, when the operation wire is wound around the groove of the pulley one or more times, the operation wire moves from the first rotation to the second rotation, and the operation wire makes one rotation from the bottom surface of the groove without floating. Since it is smoothly wound on the eye operation wire, stress concentration does not occur on the operation wire, and excellent durability that can be used for a long time without cutting the operation wire can be obtained.

[Brief description of drawings]

FIG. 1 is a plan sectional view of a pulley of an embodiment.

FIG. 2 is a side view of the pulley of the embodiment.

FIG. 3 is an external view of the endoscope of the embodiment.

[Explanation of symbols]

 7 Operation Wire 10 Pulley 11 Groove 12 Bottom 13 Hole 14 Step

Claims (1)

[Claims] 1. An operation wire is wound along a bottom surface of a groove formed by being recessed from an outer peripheral surface of a pulley which is rotationally operated, and a base end of the operation wire is a hole portion formed in the bottom surface of the groove. In the bending operation device for an endoscope, which is fixed to the pulley and then inserted into the groove, a step having a depth substantially equal to the thickness of the operation wire is formed on the bottom surface of the groove at the hole position, and the bottom surface adjacent to the step is formed. The parts are formed on both sides in a smoothly continuous curved surface, and when the operation wire is wound around the groove one or more times, the operation wire moves from the first rotation to the second rotation, and the operation wire does not float up. A bending operation device for an endoscope, wherein the operation wire is smoothly wound from the bottom surface of the groove onto the operation wire for the first rotation.