JPH02102632A - Bending operation device for endoscope - Google Patents

Abstract

PURPOSE:To obtain the bend stroke of enough quantity with a compact device by providing a loop-shaped chain or belt, which is engaged with a master wheel and a slave wheel, a pair of projecting pieces, which are respectively projected in a fastened side and a releasing side, and a pair of operating wires to be inserted through respective through holes freely slidably. CONSTITUTION:A loop-shaped roller chain 13 is spread and engaged over a prime sprocket 11 and a follower sprocket 12 without being bent. Accordingly, when an operating knob 5 is turned and the prime sprocket 11 is rotated and driven, the roller chain 11 is driven and the follower sprocket 12 is also rotated. When operating wires 6a and 6b are inserted through respective through holes 15a and 15b freely slidably and the prime sprocket 11 is rotated and driven, a stopper 16a is pushed by a projecting piece 14a and moved in the fastened side of the roller chain 13. Then, the operating wire 6a is pulled only by moving quantity M and a projecting piece 14b in the releasing side is moved in a reverse direction only by the same quantity M. However, since returning quantity N of the operating wire 6b is small in comparison with the moving quantity M, the operating wire 6b is slided to the through hole 15b in the releasing side.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bending operation device for an endoscope, and more particularly to a bending operation device in which an operation wire is pulled through a chain or a belt.

[Prior art] Endoscope bending operation devices used to pull the operation wire using a rack and pinion, pulley, etc., but in recent years, from the viewpoint of operability and reliability of the device, it has been operated using a chain, etc. Those that pull wire are widely used.

Conventionally, in a device that pulls the operating wire through a chain or the like, the operating wire on the tight side and the operating wire on the loose side are connected in the operating section, as shown in, for example, Japanese Utility Model Application No. 56-166004. The difference in the amount of movement that occurs between the chains was absorbed by making the chain itself slack.

[Problem to be Solved by the Invention] However, in order to absorb the shift in travel amount by slackening the chain itself, it is necessary to provide enough space for the chain to slacken, and in that space, If the operating wire were to enter, problems such as buckling would occur, so in the end, the space could not be used as a movement range for the operating wire. As a result, the bending operation stroke becomes correspondingly shorter, resulting in the disadvantage that a sufficient bending angle cannot be obtained. If an attempt is made to obtain the necessary amount of bending operation stroke, there is a drawback that the device becomes larger and the operability deteriorates.

The purpose of the present invention is to eliminate such drawbacks of the conventional devices and provide an endoscope bending operation device that uses a chain or belt, is compact, and can obtain a sufficient amount of bending stroke. shall be.

[Means for Solving the Problems] In order to achieve the above object, the endoscope bending operation device of the present invention includes a motive wheel rotatably provided within the operation section and rotationally driven by a drive means; A driven wheel rotatably disposed in the operating unit with a space between the driving wheel and the driven wheel, and a loop-shaped chain that is stretched over the driving wheel and the driven wheel with almost no slack and engaged with the driving wheel and the driven wheel. or a belt, a pair of protrusions protruding from the tension side and the slack side of the chain or belt, each having a through hole drilled along the moving direction of the chain or belt, and a pair of protrusions that slide into each of the through holes. It is characterized by having a pair of operating wires that are movably inserted therethrough, and a stopper that is fixed near the proximal end of each of the operating wires so as to come into contact with the motive vehicle side end of the projecting piece. .

[Operation] When the drive means rotates the motive wheel, the stopper is pushed by the projection on the tension side and moves, and the operating wire is pulled by the amount of movement. Further, the protruding piece on the loose side moves in the opposite direction by the same length as the protruding piece on the tight side. However, compared to the amount of movement, the return amount of the operating wire on the loosened side is small, so on the loosened side, the operating wire slides against the through hole and the stopper cannot keep up with the movement of the protrusion. The protrusion and the stopper are separated from each other on the slack side by the length of the difference in the amount of movement of the operating wire on the slack side and the tension side, and the difference in the amount of movement is absorbed.

In the device of the present invention, the amount of movement of the protrusion on the tension side is the amount of pulling of the operating wire, and the protrusion can move from near the driven vehicle to near the motive vehicle while pulling the operating wire. Therefore, the entire length of the dowel device can be utilized as the bending device stroke.

〔Example] Examples will be described with reference to the drawings.

FIG. 2 is an overall view of the endoscope, in which a bendable bending portion 3 is connected to the distal end portion of a flexible tube 2 connected to an operating portion 1.
A tip main body 4 containing an objective optical system and the like is connected to the tip of the curved portion 3. The tips of one or two pairs of operating wires 6 inserted into the flexible tube 2 are connected to the tips of the curved portion 3. In the figure, only one pair of operating wires 6 is shown. By rotating the operating knob 5, which is a driving means provided on the operating section 1, one of the operating wires 6 is pulled, and the bending section 3 is bent.

FIG. 1 shows a bending operation device provided within the operation section 1. As shown in FIG.

A driving sprocket 11, which is a driving wheel, is rotatably provided in the operating section 1, and this driving sprocket 11 is rotationally driven by an operating knob 5. In addition, the prime mover 11
A driven sprocket 12, which is a driven wheel, is rotatably arranged in the operating section 1 with a space therebetween.

A loop-shaped roller chain 13 is stretched around the driving sprocket 11 and the driven sprocket 12 without bending, and is engaged with both sprockets 11 and 12. Therefore, when the operating knob 5 is rotated to rotationally drive the driving sprocket 11, the roller chain 13 is thereby driven, and the driven sprocket 12 is also rotated following this.

The roller chain 13 has a pair of protrusions 14 on the tension side and slack side when the driving sprocket 11 is rotated.
a and 14b project laterally. Each protrusion 14a, 1
Through holes 15a and 15b are bored in the roller chain 4b along the moving direction of the roller chain 13. The operating wires 6a, 6b are slidably inserted into the respective through holes 15a, 15b, and the stoppers 16a, 16b fixed to the proximal ends of the operating wires 6a, 6b are connected to the motive vehicle side of the projections 14a, 14b. The end portions 14s and 14t are in contact with each other.

Therefore, for example, when the drive sprocket 11 is driven to rotate in the direction shown by the arrow R in FIG. is towed.

The protruding piece 14b on the loose side moves in the opposite direction by the same amount M. However, since the return iN of the operating wire 6b on the loose side is smaller than the movement IM, the operating wire 6b slides against the through hole 15b on the loose side, and the stopper 16b cannot keep up with the movement of the protruding piece 14b. .

In other words, the projection piece 14 on the loose side is
b and the stopper 16b are separated, and the operation wire 6a
, 6b is absorbed.

In this device, the amount of movement of the protruding piece 16a on the tension side is the amount of movement of the operating wire 6a on the tension side, but the protruding piece 16a moves from near the driven sprocket 12 to near the driving sprocket 11 while pulling the operating wire 6a. (range L in FIG. 1), and this range can be used as a bending operation stroke.

In the above embodiment, the protrusions 14a and 14b were provided protruding from the sides of the roller chain 13, but the present invention is not limited to this, and the protrusions 14a and 14b may be provided protruding from the upper or lower surface of the roller chain 13. It's okay. Further, instead of the roller chain, any type of chain may be used, and a timing belt or other belt may be used.

[Effects of the Invention] According to the endoscope bending operation device of the present invention, by using a chain or belt, etc., high operability and reliability can be obtained as an endoscope bending operation device, and moreover, a driven vehicle can be used. Since the entire length of the dowel device between the drive wheel and the motive vehicle can be used as a bending operation stroke, it has the excellent effect of being able to obtain a sufficient amount of bending stroke with a small device.

In addition, since the chain or belt, etc. is stretched across the motive vehicle and the driven vehicle without slack, there is no risk that the chain or belt, etc. will come off the motive vehicle or the driven vehicle, resulting in excellent safety. It also has the advantage of not requiring any additional information.

[Brief explanation of drawings]

FIG. 1 is a plan view of the embodiment, and FIG. 2 is an overall perspective view of the endoscope. DESCRIPTION OF SYMBOLS 1... Operation part, 3... Curved part, 6 (6a, 6b).
... Operating wire, 11... Drive sprocket, 12.
... Driven sprocket, 13 ... Roller chain, 1
4h, 14b-projection piece, 15a, 15b --- through hole, 1
6a, 16b...Stoppers. Agent Patent Attorney Kazuhiko Mitsui

Claims (1)

[Scope of Claims] A motive wheel rotatably provided within the operating section and rotationally driven by a drive means; a driven vehicle rotatably disposed within the operating section with a space from the motive wheel; and the motive vehicle. a loop-shaped chain or belt that is stretched across the motor vehicle and the driven vehicle with almost no slack to engage the motive vehicle and the driven vehicle; a pair of protrusions each having a through hole drilled along the moving direction of the protrusion, a pair of operating wires slidably inserted into each of the through holes, and abutting against the motive vehicle side end of the protrusion. The bending operation device for an endoscope is characterized in that it has a stopper fixed to the vicinity of the proximal end of each of the operation wires.