JP2608590B2 - Endoscope bending device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a bending device of an endoscope that bends a bending portion by a vibration wave motor.

2. Description of the Related Art Conventionally, as a bending operation structure for bending a bending portion of an endoscope main body, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 61-106126. This is provided with a vibration wave motor such as a small and high torque linear type ultrasonic motor as a drive motor for pulling a bending operation wire for bending a bending portion of the endoscope body. In this case, the vibration wave motor for driving the bending operation wire has a substantially U-shaped fitting member made of an elastic vibrator disposed inside the cylindrical exterior portion, and the bending operation wire is provided inside the fitting member. A part of the electrostrictive elements is held in close contact with each other, and a large number of electrostrictive elements are juxtaposed at predetermined intervals along the axial direction on three planes formed on the outer periphery of the fitting member. By generating a surface wave having a longitudinal wave and a transverse wave in the joint member, a so-called traveling vibration wave, a bending operation wire held in a frictional contact state with the fitting member is driven in the axial direction.

Further, at the time of the bending operation of the bending portion, the bending operation wire is relaxed due to the pushing / pulling operation of the bending operation wire, and the bending operation wire may be bent or buckled in the wire insertion channel. Therefore, Japanese Utility Model Publication No. Sho 51-43030 discloses a device in which a wire slack remover is provided, and the slack of the bending operation wire is removed by the slack remover.

[Problems to be Solved by the Invention] A bending operation wire is pushed and pulled by a vibration wave motor such as a linear ultrasonic motor as disclosed in JP-A-61-106126 to bend the bending portion. When the relaxation device shown in Japanese Utility Model Publication No. 51-30030 is attached to the bending device having the configuration, it is conceivable to dispose the relaxation device between the linear ultrasonic motor and the bending operation wire. . However, when a separate relaxation remover is attached to the linear ultrasonic motor in a side-by-side state to form a drive mechanism for driving the bending operation wire, the non-flexible portion having no flexibility becomes longer. However, when the drive mechanism of the bending operation wire is disposed in the insertion portion of the endoscope, for example, at the rear end of the bending portion, there is a problem that the insertion property of the insertion portion is deteriorated.
In addition, when the drive mechanism for the bending operation wire is provided in the operation unit of the endoscope, the length of the entire operation unit is increased, and there is a problem that the operability of the operation unit is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a bending device for an endoscope which can provide a function of removing and relaxing a bending operation wire without particularly increasing the size of a driving mechanism of the bending operation wire. The purpose is to do so.

[Means for Solving the Problems] The present invention provides a moving member 32 that floats along the moving direction of the rotor 25 inside the rotor 25 of the vibration wave motor 24,
A slack absorbing mechanism 33 for absorbing slack of the bending operation wire 22 by connecting the bending operation wire 22 to the moving member 32 and causing the moving member 32 to float in the rotor 25 is provided.

[Operation] When the bending operation wire 22 is relaxed due to the pushing and pulling operation of the bending operation wire 22 during the bending operation of the bending portion 7, the rotor 25 of the vibration wave motor 24 is moved with the movement of the bending operation wire 22 on the loose side. By moving the moving member 32 along the moving direction of the rotor 25 inside the inside, the slack of the bending operation wire 22 is absorbed, and the bending and bending of the bending operation wire 22 are prevented. is there.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 3 shows a schematic configuration of the entire endoscope, where 1 is an endoscope main body. An operating section 3 is connected to the endoscope main body 1 at the base end of the insertion section 2. Further, a base end of the universal cord 4 is connected to the operation unit 3. A connector 5 is provided at the tip of the universal cord 4. The insertion portion 2 is provided with a distal end portion 6, a bending portion 7, and a flexible tube portion 8, respectively. Further, the operation unit 3 is provided with an eyepiece 9 at a rear end, and an air / water switch 10, an absorption switch 11, and bending operation switches 12 (DOWN), 13 (UP),
A changeover switch 16 for switching between 14 (LEFT), 15 (RIGHT), and angle lock / free is provided.

The distal end portion 6 of the insertion section 2 is provided with an objective lens system and a light distribution lens (not shown). A light guide (not shown) is connected to the rear end of the light distribution lens. The light guide is inserted into the insertion section 2 and the universal cord 4 and connected to the connector 5. Then, by connecting the connector 5 to a light source device (not shown), the illumination light from the light source device is incident on the incident end of the light guide. The illuminating light is guided to the distal end portion 6 by the light guide, emitted from the distal end of the light guide, and illuminates the subject through the light distribution lens. The distal end surface of the image guide 17 shown in FIG. 4 is arranged at the image forming position of the objective lens system. The image guide 17 is inserted into the insertion section 2 and extends to the eyepiece section 9 side. The subject image formed on the distal end surface of the image guide 17 by the objective lens system is transmitted to the eyepiece 9 by the image guide 17 and is observed from the eyepiece 9.

4, a large number of short cylindrical joint pieces 18 are connected to the bending portion 7 so as to be rotatable in the upward and downward directions indicated by an arrow a and the left and right directions indicated by an arrow b, respectively. ing. In this case, a pair of connecting pieces 19 are each shifted 180 ° in the circumferential direction from both end faces of each joint piece 18, and each pair of connecting pieces 19 are protruded by 90 ° in the circumferential direction at both end faces, A pair of connecting pieces 19 of the adjacent joint pieces 18 are pivotally connected by support shafts 20, respectively. The connecting piece 19 protrudes from only one end face of the distal end of the bending portion 7 and the joint pieces 18a and 18b. Therefore, the bending portion 7 to which the joint piece 18 is connected in this manner is rotatable upward and downward, and left and right, respectively.

Further, cylindrical wire fixing portions 21 are provided at four positions on the inner peripheral surface of the state-of-the-art joint piece 18a, which are shifted by 90 ° in the circumferential direction corresponding to the bending direction of the bending portion 7. One end of a bending operation wire 22 is inserted into each through hole 21a of the wire fixing portion 21, and is firmly fixed by means such as brazing. In this case, the bending portion 7 has a pair of bending operation wires 22 and 22 for bending the bending portion 7 upward and downward and a bending operation of the bending portion 7 in the left and right directions. A pair of bending operation wires 22 for operation are provided, respectively. Further, the other end portions of the bending operation wires 22 are provided at four positions which are circumferentially shifted by 90 ° with respect to the inner peripheral surface of the rearmost joint piece 18b. Four wire driving portions 23a and 23b as bending driving means are provided. , 23c, 23d (the wire driving unit 23b in FIG. 4)
Are not shown). In this case, the wire driving units 23a, 23b, 23c, 23d are formed by a linear ultrasonic motor (vibration wave motor) 24 shown in FIGS.

This linear type ultrasonic motor 24 has a rotor 25 and a stator.
26 and a casing 27 are provided. In this case, the stator 26 is an elastic vibrating body made of, for example, stainless steel.
And a piezoelectric element 29 such as a piezoelectric ceramic disposed on the outer surface of the elastic vibrator. Further, the stator 26 is held in a state of being strongly pressed by the casing 27 while sandwiching the rotor 25 from two directions. In this case, the axial length of the stator 26 is
The length of the stator 25 is larger than the length in the axial direction, and when the ultrasonic motor 24 operates, the rotor 25 moves in the axial direction within the axial length of the stator 26. In addition, stoppers that regulate the operating range of the rotor 25 may be protruded from both ends of the stator 26.

The rotor 25 of the ultrasonic motor 24 is formed in a substantially cylindrical shape, and closing plates 30 and 31 are formed at both ends of the rotor 25, respectively. Further, inside the rotor 25, there is provided a moving member 32 which moves freely in the moving direction of the rotor 25. Further, a wire insertion hole 30a is formed in the closing plate 30 on one end side of the rotor 25. Further, the rear end of the bending operation wire 22 is inserted into the rotor 25 through the wire insertion hole 30a.
Is fixed to the moving member 32 by adhesive. When the bending operation wire 22 is loosened due to the pushing and pulling operation of the bending operation wire 22 during the bending operation of the bending portion 7, the rotor 25 of the ultrasonic motor 24 is moved with the movement of the bending operation wire 22 on the loose side. The slack absorbing mechanism 33 that absorbs the slack of the bending operation wire 22 by moving the moving member 22 along the moving direction of the rotor 25 inside the
It is formed integrally with itself.

 Next, the operation of the above configuration will be described.

First, when the bending section 7 is operated to bend upward when the endoscope is used, for example, the upward bending operation switch 13 of the operation section 3 is used.
Turn on. In this case, a voltage is supplied to the piezoelectric element 29 of the linear ultrasonic motor 24 in the wire driving unit 23a. Therefore, the piezoelectric element 29 expands and contracts and generates a traveling wave in the direction of pulling the bending operation wire 22 on the stator 26 of the ultrasonic motor 24, so that the rotor 25 of the ultrasonic motor 24
Moves in the direction in which the bending operation wire 22 is pulled. At this time, the moving member 32 in the rotor 25 comes into contact with the closing plate 30 with the movement of the rotor 25 and moves in the same direction with the rotor 25, so that the bending operation wire 22 fixed to the moving member 32
At the same time, and the bending portion 7 is bent upward.

Further, at the time of the bending operation of the bending portion 7 upward, the bending operation wire 22 on the wire driving portion 23c side, which is disposed to face the wire driving portion 23a, becomes the bending operation wire 22 on the wire driving portion 23a side.
Move in the opposite direction, ie, in the extrusion direction. Therefore, the rotor 25 of the ultrasonic motor 24 in the wire driving unit 23c moves in the direction in which the bending operation wire 22 is pushed. At this time,
Since the moving member 32 in the rotor 25 can be freely moved in the axial direction within the rotor 25, it is possible to prevent an excessive force from acting on the bending operation wire 22 and to prevent the bending operation wire 22 from bending. Buckling and the like can be prevented.

Therefore, in the above-described configuration, when the bending operation wire 22 is loosened due to the pushing and pulling operation of the bending operation wire 22 during the bending operation of the bending portion 7, the bending operation wire 22 is moved along the loosening side. Ultrasonic motor 24 rotor 25
The slack absorbing mechanism 33 that absorbs the slack of the bending operation wire 22 is formed integrally with the rotor 25 itself of the ultrasonic motor 24 by causing the moving member 32 to move along the moving direction of the rotor 25 inside the In addition, it is possible to provide a function of removing the loosening of the bending operation wire 22 without particularly increasing the size of the driving mechanism of the bending operation wire 22. Therefore, the insertion section 2 of the endoscope
The length of the non-flexible portion within can be relatively short,
It is possible to prevent a decrease in the insertability of the insertion section 2 of the endoscope.

FIG. 5 shows a second embodiment of the present invention. This is because four wire driving units 23a, 23b, 23 as bending driving means for operating the bending section 7 upward, downward, left, and right.
c and 23d are arranged in the operation unit 3. Therefore, in this case, it is possible to prevent the length of the entire operation unit 3 from increasing, and to prevent the operability of the operation unit 3 from being reduced. Further, in this case, the insertion section 2
Since the wire driving sections 23a, 23b, 23c, 23d can be omitted from the inside, the diameter of the insertion section 2 can be reduced.

The present invention is not limited to the above embodiment. For example, in the above embodiment, the axial length of the stator 26 is formed to be larger than the axial length of the rotor 25, and when the ultrasonic motor 24 operates, the axial length of the stator 26 falls within the axial length range. In FIG. 6, the rotor 25 moves in the axial direction, but the axial length of the rotor 25 is made smaller than the axial length of the stator 26 as in the third embodiment shown in FIG. The rotor 25 is also formed at both ends.
A configuration may be adopted in which a stopper 41 that regulates the operation range of the projection is provided. In this case, since the entire inner surface of the stator 26 can be kept in contact with the rotor 25 side at all times, the durability of the stator 26 can be improved.

Further, it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[Effects of the Invention] According to the present invention, it is possible to provide the bending operation wire loosening removal function without particularly increasing the size of the driving mechanism of the bending operation wire.

[Brief description of the drawings]

1 to 4 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a main part, FIG. 2 is a transverse sectional view of the same, and FIG. FIG. 4 is a perspective view showing a schematic configuration of a bending portion, FIG. 5 is a schematic configuration diagram of a main portion showing a second embodiment of the present invention, and FIG. 6 is a third embodiment of the present invention. It is a longitudinal section of an important section showing an example. 2 insertion section, 7 bending section, 22 bending operation wire, 24 linear ultrasonic motor (vibration wave motor), 25
... Rotor, 32 moving member, 33 slack absorbing mechanism.

Claims (1)

(57) [Claims] A bending operation wire is fixed to a distal end of a bending portion provided in an insertion portion of an endoscope, and the bending operation wire is pushed and pulled by a vibration wave motor to bend the bending portion. In the bending device for a mirror, a moving member that moves freely in a moving direction of the rotor is provided inside a rotor of the vibration wave motor, and the moving member is connected to the moving member so that the moving member is moved within the rotor. A bending device for an endoscope, comprising: a slack absorbing mechanism for absorbing slack of the bending operation wire by causing the wire to move.