JP2627549B2 - Endoscope bending operation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a bending operation device for an endoscope, and more particularly, to a bending operation device configured to pull an operation wire via a chain or a belt.

[Prior Art] The bending operation device of an endoscope used to pull an operation wire by a rack pinion or a pulley before. However, in recent years, from the viewpoint of operability and reliability of the device, the bending operation device is operated via a chain or the like. Wire pullers are widely used.

Conventionally, the operation wire is pulled through a chain or the like, as described in, for example, Japanese Utility Model Application Laid-Open No. 56-166004, in which the operation wire on the tension side and the operation wire on the loose side are connected in the operation section. The difference in the amount of movement that occurred between them was absorbed by sagging the chain itself.

[Problems to be Solved by the Invention] However, in order to allow the chain itself to sag and absorb a shift in the amount of movement, it is necessary to provide a space enough for the chain to loosen sufficiently. When the operation wire enters the space, inconvenience such as buckling occurs, so that the space cannot be used as a movement range of the operation wire. As a result, there is a disadvantage that the bending operation stroke becomes shorter by that amount, and a sufficient bending angle cannot be obtained. In order to obtain a required amount of bending operation stroke, there is a disadvantage that the apparatus becomes large and operability is reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide a bending operation device for an endoscope which solves such a conventional drawback and can obtain a sufficient amount of a bending stroke using a chain or a belt. And

[Means for Solving the Problems] In order to achieve the above object, a bending operation device for an endoscope according to the present invention is provided with a motor vehicle rotatably provided in an operation unit and rotationally driven by a driving unit, A driven vehicle rotatably disposed in the operation unit at a distance from the driving vehicle, and a loop-shaped chain which is hung over the driving vehicle and the driven vehicle almost without slack and engages the driving vehicle and the driven vehicle. Or a pair of protrusions projecting from the belt and the tension side and the slack side of the chain or the belt, respectively, and having a through-hole formed along the moving direction of the chain or the belt; It has a pair of operation wires movably inserted, and a stopper fixedly attached near the base end of each of the operation wires so as to abut on the motor vehicle side end of the protruding piece. .

[Operation] When the driving vehicle is driven to rotate by the driving means, the stopper is pushed by the protruding piece and moves on the tension side, and the operation wire is pulled by the moving amount. Further, the projecting piece on the loose side moves in the opposite direction by the same length as the projecting piece on the tension side. However, since the return amount of the operation wire on the loose side is smaller than the movement amount, the operation wire slides on the through hole on the loose side, and the stopper does not follow the movement of the protruding piece. That is, the distance between the projecting piece and the stopper on the loose side is absorbed by the length of the difference in the amount of movement of the operation wire between the loose side and the tight side, and the difference in the amount of movement is absorbed.

In the apparatus of the present invention, the moving amount of the projecting piece on the tension side is the amount of pulling of the operation wire. The projecting piece can move from the vicinity of the driven vehicle to the vicinity of the prime mover while towing the operation wire. Therefore, substantially the entire length of the device can be used as the bending device stroke.

Example An example will be described with reference to the drawings.

FIG. 2 is an overall view of the endoscope. A flexible tube 2 connected to an operation unit 1 is connected to a bendable bending portion 3 at a distal end thereof, and a distal end body 4 containing an objective optical system and the like is provided. Curved part 3
It is connected to the tip of. The distal ends of one or two pairs of operation wires 6 inserted into the flexible tube 2 are connected to the distal ends of the bending portions 3. In the figure, only one pair of the operation wires 6 is shown. By rotating an operation knob 5 which is a driving means provided on the operation unit 1, one of the operation wires 6 is pulled and the bending portion 3 is bent.

FIG. 1 shows a bending operation device provided in the operation unit 1.

A driving sprocket 11, which is a driving vehicle, is rotatably provided in the operation unit 1, and the driving sprocket 11 is rotationally driven by the operation knob 5. In addition, a driven sprocket 12, which is a driven vehicle, is rotatably disposed in the operation unit 1 at a distance from the driving vehicle 11.

A loop-shaped roller chain 13 is hung around the driving sprocket 11 and the driven sprocket 12 without bending, and is engaged with both sprockets 11, 12. Therefore, if the operation sprocket 11 is rotated by rotating the operation knob 5, the roller chain 13 is thereby driven.
Is driven, and the driven sprocket 12 is rotated accordingly.

The roller chain 13 has a pair of projections 14a, 14a on the tension side and the loose side when the driving sprocket 11 is rotationally driven.
b protrudes laterally. The projecting pieces 14a, 14b are provided with through holes 15a, 15b in the direction of movement of the roller chain 13. The operation wires 6a, 6b are slidably inserted into the through holes 15a, 15b, and the stoppers 16a, 16b fixed to the base ends of the operation wires 6a, 6b are connected to the protruding pieces 14a, 14b on the motor vehicle side. It is in contact with the ends 14s, 14t.

Therefore, for example, when the driving sprocket 11 is rotationally driven in the direction indicated by the arrow R in FIG.
On the tension side of 13, the stopper 16a is pushed by the protruding piece 14a and moves, and the operation wire 6a is pulled by the moving amount M.

The projecting piece 14b on the loose side moves by the same amount M in the opposite direction. However, since the return amount N of the operation wire 6b on the loose side is smaller than the movement amount M, the operation wire 6b slides with respect to the through hole 15b on the loose side, and the stopper 16b moves the protrusion 14b. I can't keep up.

In other words, the distance between the projecting piece 14b and the stopper 16b on the loose side is equal to the stroke difference x between the operation wire 6a on the tension side and the operation wire 6b on the loose side, and the difference between the movement amounts of the operation wires 6a and 6b is reduced. Absorbed.

In this device, the movement amount of the tension-side protrusion 16a is the movement amount of the tension-side operation wire 6a, but the protrusion 16a is pulled from the vicinity of the driven sprocket 12 to the vicinity of the driving sprocket 11 while pulling the operation wire 6a. (The range L in FIG. 1) can be moved, and this range L can be used as a bending operation stroke.

In the above embodiment, the projecting pieces 14a, 14b project from the side of the roller chain 13, but the present invention is not limited to this, and the projecting pieces 14a, 14b project from the upper surface or the lower surface of the roller chain 13. You may. Further, instead of the roller chain, any type of chain may be used, and a timing belt or another belt may be used.

[Effects of the Invention] According to the bending operation device for an endoscope of the present invention, high operability and reliability are obtained as a bending operation device for an endoscope by using a chain or a belt, and a driven vehicle is used. Since almost the entire length of the device between the motor and the prime mover can be used as the bending operation stroke, there is an excellent effect that a sufficient amount of bending stroke can be obtained with a small device.

In addition, since the chain or belt is hung around the prime mover and the driven vehicle without slack, there is no risk that the chain or belt will come off from the prime mover or the driven vehicle, and the safety is excellent, and a chain cover surrounding the periphery is also required. And the like.

[Brief description of the drawings]

FIG. 1 is a plan view of the embodiment, and FIG. 2 is an overall perspective view of the endoscope. 1 ... operating part, 3 ... bending part, 6 (6a, 6b) ... operating wire, 11 ... driving sprocket, 12 ... driven sprocket, 13 ... roller chain, 14a, 14b ... protruding piece, 15a , 15b
... Through holes, 16a, 16b ... Stoppers.

Claims (1)

(57) [Claims] 1. A driving vehicle rotatably provided in an operation unit and rotationally driven by a driving means, a driven vehicle rotatably disposed in the operation unit at a distance from the driving vehicle, A loop-shaped chain or belt that is hung on the driven vehicle almost without slack and engages with the driven vehicle and the driven vehicle; and a projecting portion is provided on the tension side and the loose side of the chain or belt, respectively. A pair of projecting pieces each having a through hole formed along the moving direction, a pair of operation wires slidably inserted through the respective through holes, and a motor vehicle side end of the projecting piece. A bending operation device for an endoscope, further comprising a stopper fixedly attached to a base end portion of each of the operation wires.