JP2016221025A - Endoscope apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope apparatus which does not reduce an operation property when a curvature amount of a curve part is small, and fixes a position of an operation shaft even when the curvature amount is large.SOLUTION: An endoscope apparatus is configured to perform an operation by towing angle wires 19A, 19B. The endoscope apparatus comprises: an operation shaft 11 supported tiltably with respect to a center axis Z; a salient-state part 12 to which end parts of the angle wires 19A, 19B are fixed, and moves according to tilt of the operation shaft 11; and reception members such as a first reception member 16A, and second reception members 16BL, 16BR, to which the salient-state part 12 contacts slidably. When a tilt angle of the operation shaft 11 to the center axis Z exceeds a constant value, as a tilt angle increases, a contact area between the salient-state part 12 and second reception members 16BL, 16BR increases.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an endoscope apparatus.

Conventionally, endoscope apparatuses are used in the industrial field, the medical field, and the like. The endoscope apparatus is used by inserting a long and thin insertion part into a structure or a living body as a subject.
On the distal end side of the insertion portion of the endoscope device, a bending portion that can be operated by an operation portion provided at the proximal end portion of the endoscope device is provided.
The bending portion is operated to bend by pulling the wire with the operation portion.
As an operation unit of such an endoscope apparatus, a joystick type operation unit is known. The joystick-type operation unit pulls the rotating body, to which the wire is locked, by tilting the operation shaft (see, for example, Patent Documents 1 and 2).

Japanese Patent No. 5161529 JP 2012-1000068 A

However, the conventional endoscope apparatus as described above has the following problems.
In the joystick type operation unit, the rotating body that rotates by tilting the operation shaft is locked by frictional force, and the tilted position of the operation shaft after tilting is maintained.
The amount of bending force that bends the bending portion increases as the amount of bending increases. Therefore, in the conventional joystick type operation unit, the frictional force acting on the rotating body is set to a magnitude that can resist the maximum amount of bending force in order to maintain the tilting position even when the amount of bending is large.
For this reason, in the conventional joystick type operation unit, the same frictional force as that when the bending amount is large acts when performing an operation with a small bending amount or when finely adjusting the bending amount. Therefore, when an operation with a small amount of bending is performed, there is a problem that an operation load becomes heavy and it is difficult to perform a smooth operation or a delicate operation.

  The present invention has been made in view of the above-described problems, and does not deteriorate the operability when the bending amount of the bending portion is small, and the position of the operation shaft can be fixed even when the bending amount is large. An object of the present invention is to provide an endoscope apparatus.

  In order to solve the above problems, an endoscope apparatus according to an aspect of the present invention is an endoscope apparatus that is operated by pulling a wire, and is supported so as to be tiltable with respect to a neutral axis. A tilting portion of the operating shaft with respect to the neutral axis, comprising: a shaft; a moving member to which an end portion of the wire is fixed and moving with tilting of the operating shaft; and a receiving member with which the moving member is slidably contacted When the angle exceeds a certain value, the contact area between the moving member and the receiving member increases as the tilt angle increases.

  In the endoscope apparatus, the receiving member includes a plurality of receiving surfaces that can come into contact with the moving member, and when the tilt angle of the operation shaft exceeds a certain value, the receiving members on the receiving surfaces The number of moving members and contact portions may vary.

  In the endoscope apparatus, at least one of the receiving member and the moving member is made of an elastic member, and the amount of elastic deformation of the elastic member increases as the tilt angle of the operation shaft increases, so that the receiving member The normal force acting on the moving member may be increased.

  In the endoscope apparatus, the receiving member may constrain the moving member so as to be rotatable about one point.

  In the endoscope apparatus, the moving member includes a first moving unit disposed on the opposite side of the operation end of the operation shaft from the tilt center of the operation shaft, and a tilt center of the operation shaft. A second moving portion disposed near the operation end of the operation shaft, wherein the receiving member is capable of contacting the first moving portion, the first moving portion, and the second moving portion. And a second receiving portion that can be contacted.

  According to the endoscope apparatus of the present invention, there is an effect that the position of the operation shaft can be fixed even when the bending amount is large without deteriorating the operability when the bending amount of the bending portion is small.

It is a typical perspective view showing composition of an endoscope apparatus of a 1st embodiment of the present invention. It is typical sectional drawing which shows the structure of the operation part of the endoscope apparatus of the 1st Embodiment of this invention. It is a typical perspective view which shows the structure of the principal part of the operation part of the endoscope apparatus of the 1st Embodiment of this invention. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is CC sectional drawing in FIG. It is operation | movement explanatory drawing of the operation part of the endoscope apparatus of the 1st Embodiment of this invention. It is operation | movement explanatory drawing of the operation part of the endoscope apparatus of the 1st Embodiment of this invention. It is a schematic diagram which shows the change of the contact area between a moving member and a receiving member. It is a schematic diagram which shows the change of the contact area between a moving member and a receiving member. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 1st modification of the 1st Embodiment of this invention. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 2nd modification of the 1st Embodiment of this invention. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 3rd modification of the 1st Embodiment of this invention. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 4th modification of the 1st Embodiment of this invention. It is DD sectional drawing in FIG. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 2nd Embodiment of this invention. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 3rd Embodiment of this invention. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 4th Embodiment of this invention. It is operation | movement explanatory drawing of the operation part of the endoscope apparatus of the 5th Embodiment of this invention. It is a typical perspective view which shows the structure of the principal part of the operation part of the endoscope apparatus of the 6th Embodiment of this invention. It is EE sectional drawing in FIG. It is typical sectional drawing which shows the structure of the principal part of the operation part of the endoscope apparatus of the 7th Embodiment of this invention. It is FF sectional drawing in FIG. It is the typical front view which shows the structure of the receiving member used for the endoscope apparatus of the 5th modification of the 1st Embodiment of this invention, and its G view.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
An endoscope apparatus according to a first embodiment of the present invention will be described.
FIG. 1 is a schematic perspective view showing the configuration of the endoscope apparatus according to the first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing the configuration of the operation unit of the endoscope apparatus according to the first embodiment of the present invention. FIG. 3 is a schematic perspective view illustrating the configuration of the main part of the operation unit of the endoscope apparatus according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 5 is a cross-sectional view taken along the line BB in FIG. 6 is a cross-sectional view taken along the line CC in FIG.
In addition, since each drawing is a schematic diagram, the shape and dimension are exaggerated (the following drawings are also the same).

As shown in FIG. 1, the endoscope apparatus 1 of this embodiment includes an insertion unit 2, an operation unit 6, and a display unit 8.
The endoscope apparatus 1 may be an industrial endoscope apparatus or a medical endoscope apparatus.
The insertion portion 2 is a long device portion for insertion into the subject. When the endoscope apparatus 1 is an industrial endoscope apparatus, the subject is a structure to be examined. When the endoscope apparatus 1 is a medical endoscope apparatus, the subject is a human body or a biological tissue to be examined.

Below, when explaining the shape and the arrangement position of each member in the endoscope apparatus 1, when there is no possibility of misunderstanding, the distal end portion (side) and the proximal end portion (side) in the insertion direction of the insertion portion 2. May be simply referred to as a distal end (side) or a proximal end (side). Further, the direction along the central axis of the insertion portion 2 may be referred to as the axial direction.
In addition, when describing the relative position with respect to a member such as a shaft or cylinder that can specify an axis such as the central axis, the direction along the axis is the axial direction, the direction around the axis is the circumferential direction, and the plane orthogonal to the axis The direction along the line intersecting the axis is called the radial direction. In the radial direction, the direction away from the axis may be referred to as radially outward (outside), and the direction approaching the axis may be referred to as radial inward (inside).

The insertion portion 2 includes a distal end portion 3, a bending portion 4, and a flexible tube portion 5 from the distal end side toward the proximal end side.
The distal end portion 3 of the insertion portion 2 houses an illumination optical system that illuminates the inspection target portion, an imaging optical system that acquires an image of the inspection target portion, and an imaging element. The tip 3 has a substantially cylindrical outer shape covered with a hard exterior member.

The bending portion 4 of the insertion portion 2 is a device portion that changes the position and posture of the distal end portion 3 with respect to the distal end of the flexible tube portion 5 described later. The bending portion 4 can be independently bent in two axial directions orthogonal to each other within a plane orthogonal to the axial direction of the insertion portion 2.
For example, the bending portion 4 is formed in an annular shape and has a hollow cylindrical structure including a plurality of bending pieces connected to each other so as to be rotatable. The outer peripheral portion of the bending portion 4 is covered with, for example, an outer skin member made of a tube body.

Each bending piece of the bending portion 4 is provided with wire insertion holes at positions that divide the inner peripheral surface into four equal parts in the circumferential direction, and angle wires, which will be described later, are inserted into these wire insertion holes.
In the bending portion 4, a light guide for supplying illumination light to the signal line connected to the image sensor and the illumination optical system is inserted into an inner hole portion surrounded by the inner peripheral surface of each bending piece.

The flexible tube portion 5 of the insertion portion 2 inserts the distal end portion 3 and the bending portion 4 located on the distal end side of the insertion portion 2 into the subject and moves to the examination target site along the insertion path in the subject. It is a device part to make it.
A signal line, a light guide, and an angle wire extending from the bending portion 4 are inserted into the flexible tube portion 5. However, the angle wire is inserted into the coil sheath described later so that the path length does not change even when the flexible tube portion 5 is bent.
The flexible tube portion 5 can be configured, for example, by externally covering a flex tube in which a metal plate or a resin plate is spirally wound as required. For example, the flexible tube portion 5 may be formed of a resin tube.

  The operation unit 6 is a device part that performs an operation of bending the bending unit 4 by pulling the angle wire inserted through the insertion unit 2. The operation unit 6 may include, for example, a button, a switch, or the like that performs an operation using an electric circuit such as turning on / off an LED unit 29 described later. However, the operation unit for performing an operation using an electric circuit may be provided in the display unit 8 described later without being provided in the operation unit 6. In the present embodiment, although not shown, a switch for turning on / off the LED unit 29 described later is provided in the display unit 8 described later as an example.

The operation unit 6 is connected to the base end portion 5 a of the flexible tube unit 5.
As shown in FIG. 2, the operation unit 6 includes a distal end side exterior member 25 connected to the proximal end portion 5 a of the flexible tube part 5, and a proximal end side exterior member connected to the proximal end side of the distal end side exterior member 25. Member 24.
The distal end side exterior member 25 and the proximal end side exterior member 24 are both tubular members as a whole.
Inside the distal end side exterior member 25 and the proximal end side exterior member 24, the coil sheath fixing portion 27, the LED unit 29, and the operation portion main body 10 are arranged.

The coil sheath fixing portion 27 is a member that fixes the proximal end of the coil sheath 126 inserted into the flexible tube portion 5. The coil sheath fixing portion 27 is inserted into a hole inside the distal end side exterior member 25 and is fixed to the coil sheath fixing portion 27 by an annular retaining ring 133.
A coil sheath base 28 at the base end portion of the coil sheath 126 is fixed to the coil sheath fixing portion 27. In the present embodiment, there are four coil sheaths 126.

In the endoscope apparatus 1 of the present embodiment, the bending portions 4 can be bent independently in the biaxial directions. Therefore, a pair of angle wires 19A (wire, see FIG. 2) and a pair of angle wires 19B (wire, see FIG. 3) are inserted through the bending portion 4 in the axial direction.
Although illustration is omitted, inside the bending portion 4, the pair of angle wires 19 </ b> A are disposed at positions facing each other across the central axis of the bending portion 4. Inside the bending portion 4, the pair of angle wires 19 </ b> B are arranged at positions facing each other across the central axis of the bending portion 4. However, the opposing direction of the angle wires 19A and the opposing direction of the angle wires 19B are shifted by 90 °.
The distal end portions of the angle wires 19 </ b> A and 19 </ b> B are both fixed to the proximal end portion of the distal end portion 3.
Although not shown, a coil sheath fixing portion similar to the coil sheath fixing portion 27 is fixed to the proximal end portion of the bending portion 4. A coil sheath base at the distal end portion of the coil sheath 126 is fixed to the coil sheath fixing portion at the proximal end portion of the bending portion 4.
The angle wires 19A and 19B are inserted into the coil sheaths 126 one by one.

  The fixing position of the coil sheath base 28 in the coil sheath fixing part 27 is a position that divides the circumference around the center axis N (see FIG. 2) of the coil sheath fixing part 27 into four equal parts in the circumferential direction. As shown in FIG. 2, the pair of angle wires 19 </ b> A are inserted through the coil sheaths 126 that face each other across the central axis N. Although not shown, the pair of angle wires 19B are similarly inserted through the coil sheaths 126 facing each other with the central axis N therebetween.

The LED unit 29 is a light source that supplies illumination light to the illumination optical system of the distal end portion 3. The LED unit 29 is fixed to the central portion of the coil sheath fixing portion 27.
A light guide 134 that guides illumination light emitted from the LED unit 29 to an illumination optical system (not shown) at the distal end portion 3 is connected to the distal end portion of the LED unit 29.
The light guide 134 is inserted into the flexible tube portion 5 and the bending portion 4. The distal end portion of the light guide 134 is disposed in the vicinity of an illumination optical system (not shown) at the distal end portion 3.

  The signal line 35 connected to the image pickup device of the distal end portion 3 and inserted into the bending portion 4 and the flexible tube portion 5 is inserted into the cable 7 connected to the side surface of the distal end side exterior member 25. The signal line 35 is connected to the display unit 8 described later through the cable 7.

The operation portion main body 10 is a joystick type device portion that pulls the angle wires 19A and 19B extending from the coil sheath base 28 toward the proximal end side.
The operation unit body 10 includes a support frame 14, a first receiving member 16 </ b> A (receiving member, elastic member), a convex portion 12 (moving member), a wire locking plate 13 (moving member), and an operating shaft 11.

The support frame 14 has a rectangular parallelepiped outer shape extending along the central axis Z. The support frame 14 can be formed of either metal or resin, or a combination of metal and resin.
On the first side surface 14A, which is the side surface on the base end side of the support frame 14 (the side surface on the upper side in FIG. 2), an upper opening 14a through which an operation shaft 11 described later passes is formed.
A lower opening 14f is formed in the second side surface 14B which is the side surface on the front end side of the support frame 14 (the lower side surface in FIG. 2). The distal end portion of the support frame 14 is inserted into the hole portion of the distal end side exterior member 25 and fixed to the distal end side exterior member 25.

  Hereinafter, in a plan view (hereinafter simply referred to as a plan view) in which the support frame 14 is viewed from the proximal end side toward the distal end side, a direction along one side of a rectangular shape (including a square) of the support frame 14 is illustrated. 3, the first direction X and the direction orthogonal to the first direction X are referred to as a second direction Y.

As shown in FIG. 4, on the first side surface 14A, a pair of support plates 17 are fixed to the front-side surface surrounding the upper opening 14a.
The pair of support plates 17 are a pair of plate members that protrude from the first side surface 14 </ b> A to the inside of the support frame 14, and face each other in the first direction X.
Each support plate 17 includes bearing portions 17a that face each other in the first direction X. A central axis C1 that connects the centers of the bearing portions 17a extends in the first direction X and is an axis that is orthogonal to the central axis Z.

Between the pair of support plates 17, a rotation shaft 18 that supports an operation shaft 11 to be described later is disposed.
The rotating shaft 18 includes a main body portion 18d, a shaft portion 18a, a slit 18b, and a bearing portion 18c (see FIG. 5).
The main body 18d has a cylindrical outer shape.
The shaft portion 18a is formed in a shaft shape thinner than the main body portion 18d. The shaft portion 18a protrudes coaxially with the main body portion 18d at both axial ends of the main body portion 18d. Each shaft portion 18 a is rotatably fitted to the bearing portion 17 a of the support plate 17.
The rotating shaft 18 is supported coaxially with the central axis C1 by the support plate 17 by engaging each shaft portion 18a with the bearing portion 17a of the support plate 17.
The length of the main body 18 d of the rotating shaft 18 is slightly shorter than the interval between the support plates 17.

The slit 18b passes through the central portion of the rotating shaft 18 in a direction orthogonal to the central axis of the shaft portion 18a.
The opening width of the slit 18 b is wide in the axial direction of the rotary shaft 18 and narrow in the radial direction of the rotary shaft 18.
The short width of the slit 18b is a size that allows a shaft 11b of the operation shaft 11 described later to be movably fitted.
The longitudinal width of the slit 18b is a size that does not interfere with the shaft portion 11b in a tilting range of the shaft portion 11b described later.

The bearing portion 18c includes a through hole that rotatably supports the tilting shaft 11c protruding from the operation shaft 11.
The bearing portion 18 c is formed at the axial center position of the rotary shaft 18. The center axis C2 (see FIG. 5) of the bearing portion 18c is in a positional relationship orthogonal to the center axis of the shaft portion 18a coaxial with the center axis C1.

As shown in FIG. 4, the rotation shaft 18 is positioned in the axial direction by sandwiching the main body 18 d between the pair of support plates 17.
In a state where the rotary shaft 18 is positioned by each support plate 17, the intersection point O between the center axis C2 and the center axis C1 of the bearing portion 18c is located on the center axis Z. The point O is a point that becomes the center of tilt of the operation shaft 11 described later.

As shown in FIG. 3, an opening 14 e is formed on the side surface of the support frame 14 that faces each other in the first direction X or the second direction Y.
In the support frame 14, a support plate portion 14 c orthogonal to the central axis Z is provided between the side surfaces facing each other in the first direction X and the second direction Y at the intermediate portion between the front end and the base end. .
As shown in FIGS. 3 and 6, substantially rectangular hole portions 14 d penetrate in the plate thickness direction in the diagonal direction of the support plate portion 14 c in plan view.
Inside each opening 14e, the leaf | plate spring part 14b which protrudes in a base end side rather than the support plate part 14c is arrange | positioned. The leaf spring portions 14b are composed of a total of four pairs, one pair facing the first direction X across the central axis Z and one pair facing the second direction Y.
Each leaf spring portion 14b is formed in a rectangular plate shape that bends in the opposite direction when receiving an external force.

As shown in FIG. 4, the first receiving member 16A (receiving member) is fixed to the center portion of the support plate portion 14c.
16 A of 1st receiving members are members which contact the convex-shaped part 12 mentioned later in the direction in alignment with the central axis Z. As shown in FIG.
The first receiving member 16A is a columnar member that protrudes from the base end side surface of the support plate portion 14c to the base end side. In the present embodiment, the central axis in the protruding direction of the first receiving member 16A is coaxial with the central axis Z.
A receiving surface 16a that is an end surface in the protruding direction of the first receiving member 16A is a concave spherical surface having a radius R.
The receiving surface 16a is arranged at a position where the center of curvature is coaxial with the central axis Z and the distance along the central axis Z from the point O is slightly shorter than R.
The convex part 12 mentioned later contacts the receiving surface 16a so that sliding is possible along the receiving surface 16a. 16 A of 1st receiving members are pressed by the convex part 12 mentioned later via the receiving surface 16a by being supported by the leaf | plate spring part 14b.

  As the material of the first receiving member 16A, an appropriate material can be selected according to the frictional force required when contacting the convex portion 12 described later. The first receiving member 16A can employ an elastic member having lower rigidity than the support plate portion 14c when an external force along the central axis Z acts. In the present embodiment, the material of the first receiving member 16A is rubber or elastomer that is an elastic member.

As shown in FIG. 4, second receiving members 16BL and 16BR (receiving members) are fixed to end portions in the protruding direction of the respective leaf spring portions 14b facing each other in the first direction X.
As shown in FIG. 5, second receiving members 16CL and 16CR (receiving members) are fixed to end portions of the leaf spring portions 14b facing each other in the second direction Y in the protruding direction.
2nd receiving member 16BL, 16BR, 16CL, 16CR is a member which contacts the peripheral part of the convex-shaped part 12 mentioned later in the direction which cross | intersects the central axis Z. As shown in FIG.
The second receiving members 16BL, 16BR, 16CL, and 16CR are all columnar members that protrude from the surface of the leaf spring portion 14b toward the central axis Z.
The receiving surface 16b which is an end surface in the protruding direction of the second receiving members 16BL, 16BR, 16CL, and 16CR is a concave spherical surface having a radius R.

The receiving surfaces 16b of the second receiving members 16BL and 16BR are arranged at positions where the center of curvature is coaxial with the central axis C1 and the distance from the point O along the central axis C1 is slightly shorter than R. Is done.
The receiving surfaces 16b of the second receiving members 16CL and 16CR are arranged at positions where the center of curvature is coaxial with the central axis C2 and the distance along the central axis C2 from the point O is slightly shorter than R. Is done.
The arrangement position of each receiving surface 16b determines the vertical drag force from the second receiving members 16BL, 16BR, 16CL, and 16CR to the convex portion 12 to be described later, and a frictional force to the convex portion 12 to be described later is generated. That is, the frictional force acting on the convex portion 12 to be described later can be adjusted, for example, by appropriately setting the arrangement position of each receiving surface 16b and changing the vertical drag.
The frictional force acting on the convex portion 12 from each receiving surface 16b is large enough to balance the force transmitted from the angle wires 19A and 19B to the convex portion 12 as a force to return the bending received by the bending portion 4 during the bending operation. Say it. Thereby, the convex part 12 mentioned later can be hold | maintained by the frictional force which acts from each receiving surface 16b.

The base end portions (upper end portions in the drawing) of the second receiving members 16BL, 16BR, 16CL, and 16CR do not protrude from the base end side even if the convex portion 12 described later is rotated to the maximum. It is extended to the position.
On the other hand, when the convex portions 12 described later rotate beyond the threshold θth from the neutral state described later, the tip portions (lower end portions in the drawing) of the second receiving members 16BL, 16BR, 16CL, 16CR are rotated. A part of the convex portion 12 in the rotation direction is extended to a position where it can be removed to the tip side.

As the material of the second receiving members 16BL, 16BR, 16CL, and 16CR, an appropriate material can be selected according to the frictional force required when contacting the convex portion 12 described later. The second receiving members 16BL and 16BR (16CL and 16CR) can employ elastic members having lower rigidity than the leaf spring portion 14b when an external force along the central axis C1 (C2) acts. In the present embodiment, the material of the second receiving members 16BL, 16BR (16CL, 16CR) is rubber or elastomer which is an elastic member.
The second receiving members 16BL, 16BR, 16CL, and 16CR may be made of the same material as the first receiving member 16A or may be made of a different material. In the case of different materials, the friction coefficient of the second receiving members 16BL, 16BR, 16CL, and 16CR with respect to the convex portion 12 described later may be a material that is larger than the friction coefficient of the first receiving member 16A with respect to the convex portion 12. Good.

The convex portion 12 is a shell-like member having a convex surface 12a having a shape obtained by cutting a spherical surface having a radius R at a height smaller than the radius.
In the convex portion 12, a wire locking plate 13 described later is fixed to the end surface 12 b opposite to the vertex P.
4 and 5 show a state in which the convex portion 12 is arranged at a position where the central axis s of the convex surface 12a passing through the apex P is coaxial with the central axis Z. FIG. At this time, the end surface 12b is located on a plane orthogonal to the central axis Z.

The wire locking plate 13 is a member for fixing the base end portions of the angle wires 19A and 19B extending from the coil sheath base 28 into the operation portion 6. A method for fixing the base ends of the angle wires 19A and 19B to the wire locking plate 13 is not particularly limited.
For example, a through hole through which the angle wire 19A (19B) is inserted is provided in the thickness direction of the wire locking plate 13, and a locking member that can be locked in the through hole is attached to the base end of the angle wire 19A (19B). May be. In this case, the locking member is locked in the through hole by the tension of the angle wire 19A (19B) inserted through the through hole, and the base ends of the angle wires 19A and 19B are fixed.
The base ends of the angle wires 19A and 19B are not simply locked to the wire locking plate 13, but may be fixed to the wire locking plate 13 in a non-detachable manner by fixing means such as welding, caulking, or adhesion. .

As shown in FIG. 6, in this embodiment, the wire locking plate 13 is a plate member having a cross-like shape in plan view in which four arm portions 13b protrude from a center portion 13a that is circular in plan view.
The center of the central portion 13a is located coaxially with the central axis s of the convex surface 12a. In the center of the center portion 13a, a hole portion 13c for fitting a shaft portion 11b of the operation shaft 11 described later is penetrated.
Each arm portion 13b extends along two straight lines that pass through the center of the center portion 13a and are orthogonal to each other. Each arm portion 13 b protrudes radially outward from the end surface 12 b of the convex portion 12. The proximal ends of the angle wires 19A and 19B are locked to the distal ends of the extending portions of the arm portions 13b via the locking members 13d on the outer side in the radial direction from the end surface 12b.
Each arm part 13b is arrange | positioned along the diagonal inside the support frame 14 by planar view. For this reason, as shown in FIGS. 4 and 5, the angle wires 19A and 19B connected to the locking member 13d pass through the radially outer side of the convex portion 12 and extend to the tip side through the hole 14d.
In the present embodiment, the base end portion of the angle wire 19A is provided between the arm portion 13b positioned between the second receiving members 16CR and 16BR and the arm portion 13b positioned between the second receiving members 16BL and 16CL. It is locked.
The base end portion of the angle wire 19B is locked to the arm portion 13b positioned between the second receiving members 16BL and 16CR and the arm portion 13b positioned between the second receiving members 16CL and 16BR. .

The wire locking plate 13 is formed of a metal or a resin having such rigidity that deformation is negligible even when an external force is received from the angle wires 19A and 19B and an operation shaft 11 described later.
In the present embodiment, the wire locking plate 13 has a cross shape in plan view, which prevents the wire locking plate 13 from interfering with the support plate 17 and the rotating shaft 18 when the convex portion 12 rotates. Because. It is not essential to form the wire locking plate 13 in a cross shape in plan view.
For example, the central portion 13a of the wire locking plate 13 is formed on the end surface 12b of the convex portion 12 when interference with the support plate 17 and the rotating shaft 18 does not occur even when the convex portion 12 rotates to the maximum. You may extend to the position which contact | abuts.

  As described above, in the endoscope apparatus 1, the end portions of the angle wires 19 </ b> A and 19 </ b> B are engaged with the distal end portion 3 at the distal end side, and the end portion on the proximal end is engaged with the wire locking plate 13. Stopped. Initial tension is given to each angle wire 19A, 19B at the time of assembly so that no slack occurs in any of them.

As shown in FIGS. 4 and 5, the operation shaft 11 is a shaft-like member for performing a bending operation of the bending portion 4. As will be described later, the operation shaft 11 is supported by the rotation shaft 18 supported by the support plate 17 so as to be tiltable about the point O with respect to the center axis Z.
The operation shaft 11 includes a shaft portion 11b, a tilt shaft 11c, and an operation head 11a (operation end portion).

The shaft portion 11 b is a shaft-like member inserted through the slit 18 b of the rotating shaft 18 and the hole portion 13 c of the wire locking plate 13.
The first end e1 of the shaft portion 11b is fixed to the inner peripheral surface on the back side of the vertex P of the convex portion 12. The central axis S of the shaft portion 11b is coaxial with the central axis s of the convex surface 12a.
In the shaft portion 11b, the second end e2 opposite to the first end e1 is, as shown in FIG. 2, the upper opening 14a of the support frame 14 and the opening 24a of the base end side exterior member 24 (see FIG. 1). ) Extending outside the operation unit 6.

As shown in FIGS. 4 and 5, the tilting shaft 11 c is a shaft-like portion protruding in a direction perpendicular to the central axis S of the shaft portion 11 b from the side portion of the shaft portion 11 b. A central axis D (see FIG. 5) of the tilt axis 11c is orthogonal to the central axis S at a position where the distance from the apex P of the convex surface 12a is R.
The tilting shaft 11c is fitted to the bearing portion 18c of the rotating shaft 18 so as to be rotatable.
The length of the shaft portion 11b of the operation shaft 11 may be determined so that an operation amount and an operation force for moving the operation head 11a described later have an appropriate magnitude. As an example, the length of the shaft portion 11b in the present embodiment is a length that is two to three times R.

The operation head 11a is formed in an appropriate shape that is thicker than the shaft portion 11b so that the operator can easily hold it during operation. The operation head 11a can have an appropriate shape such as a spherical shape, a hemispherical shape, a truncated cone shape, or a cylindrical shape.
The operation head 11a is fixed to the second end e2 of the shaft portion 11b.

As shown in FIG. 2, in the operation shaft 11, the operation head 11a and a part of the shaft portion 11b are extended to the base end side through the upper opening 14a.
The upper opening 14 a of the support frame 14 is exposed inside the opening 24 a on the base end side of the base end side exterior member 24. The operation shaft 11 extends to the outside through the opening 24 a of the base end side exterior member 24.
A rubber boot 23 is mounted between the base end portion of the base end side exterior member 24 and the shaft portion 11b.

  The rubber boot 23 is a flexible cover that covers the space between the base end portion of the base end side exterior member 24 and the shaft portion 11b. The rubber boot 23 prevents the upper opening 14 a of the support frame 14 and the opening 24 a of the base end side exterior member 24 from communicating with the outside. The configuration of the rubber boot 23 is not particularly limited as long as it is easily deformed when the operation shaft 11 is tilted and does not hinder the tilt of the operation shaft 11. In the present embodiment, the rubber boot 23 is made of rubber formed in a bellows shape.

The operation shaft 11 having such a configuration is supported to be tiltable around a point O by a pair of support plates 17 fixed to the support frame 14 and a rotation shaft 18 supported by the support plate 17.
The shaft portion 11b can be tilted about the central axis C2 by the tilt shaft 11c supported by the bearing portion 18c. Further, the shaft portion 11b can tilt about the central axis C2 by rotating integrally with the rotary shaft 18 supported so as to be rotatable about the central axis C1 by the bearing portion 17a of the support plate 17.
Since the shaft part 11b can be tilted independently around the central axes C1 and C2, the shaft part 11b can tilt independently in the second direction Y and the first direction X, respectively.
As a result, the operation shaft 11 can tilt in all directions perpendicular to the central axis Z with respect to the central axis Z around the point O.

As shown in FIG. 1, the display unit 8 is a device part that displays an image captured by the image sensor of the tip 3.
The display unit 8 includes, for example, an image processing unit that performs image processing on a video signal transmitted from the image sensor, a liquid crystal display that displays video processed by the image processing unit, and each device portion of the endoscope apparatus 1. And a battery for supplying electric power as needed.
Although illustration is omitted, in the present embodiment, the display unit 8 also includes a switch for turning on / off the LED unit 29.

  A signal line 35 inserted through the cable 7 extending from the distal end side exterior member 25 of the operation unit 6 is electrically connected to the image processing unit of the display unit 8. The video signal imaged by the imaging device at the distal end portion 3 is sent to the image processing unit through the signal line 35.

  Since the display unit 8 is connected to the operation unit 6 by a flexible cable 7, the operator of the endoscope apparatus 1 is arranged at a position where the display unit 8 can be easily seen, and is displayed on the display unit 8. The operation unit 6 can be operated while looking at the screen.

Next, the operation of the endoscope apparatus 1 according to the present embodiment will be described focusing on the operation related to the operation of the operation unit 6.
7 and 8 are operation explanatory diagrams of the operation unit of the endoscope apparatus according to the first embodiment of the present invention. 9 and 10 are schematic views showing changes in the contact area between the moving member and the receiving member.

In order to observe the inside of the subject with the endoscope apparatus 1, the insertion portion 2 of the endoscope apparatus 1 is inserted into the subject, and the distal end portion 3 is disposed near the observation target. When the LED unit 29 is turned on by operating a switch (not shown) in the display unit 8, illumination light is emitted from the tip 3. The imaging device at the distal end portion 3 can capture an image in the imaging range where the optical axis of the imaging optical system is directed through the imaging optical system at the distal end portion 3.
The video signal of the image sensor is sent to the display unit 8 through the signal line 35. The display unit 8 displays an image based on the video signal.

  The operator of the endoscope apparatus 1 can change the position and posture of the distal end portion 3 with respect to the distal end of the flexible tube portion 5 by bending the bending portion 4. By changing the position and posture of the distal end portion 3 with respect to the distal end of the flexible tube portion 5, an image of another part of the subject can be displayed on the display portion 8.

In order to bend the bending portion 4, the operator operates the operation shaft 11 of the operation portion 6.
The operation shaft 11 is in a neutral state shown in FIGS. 4 and 5 before the operation is started.
In the neutral state, the central axis S of the operation shaft 11 is coaxial with the central axis Z of the support frame 14 that is a neutral axis. Since the central axis S of the operation shaft 11 is coaxial with the central axis e of the convex portion 12, the vertex P of the convex surface 12a is also located on the central axis Z. For this reason, the distance between the point O and the center of the first receiving member 16A is equal to the distance R between the point O and the vertex P.

The convex surface 12a of the convex portion 12 is in contact with the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, 16CR. Since the receiving surface 16a of the first receiving member 16A and the receiving surfaces 16b of the second receiving members 16BL, 16BR, 16CL, and 16CR protrude from the point O to the inside in the radial direction from the spherical surface of the distance R, respectively. The member 16A and the second receiving members 16BL, 16BR, 16CL, 16CR receive a compressive force. Since the second receiving members 16BL, 16BR, 16CL, and 16CR are further supported by the leaf spring portion 14b, the leaf spring portion 14b bends radially outward.
As a result, the convex portion 12 receives a reaction force radially inward from the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, 16CR.

When the operator applies a force to the operation head 11a of the operation shaft 11 in a direction intersecting the operation head 11a, the operation shaft 11 tilts around the point O with respect to the central axis Z. The operation shaft 11 can be tilted independently in the biaxial direction by the support plate 17 and the rotation shaft 18. For this reason, the tilt direction can be tilted in an arbitrary radial direction centered on the central axis Z in a plan view viewed from the direction along the central axis Z.
When the operation shaft 11 tilts, the convex portion 12 and the wire locking plate 13 rotate around the point O. The magnitude of the tilt angle of the operation shaft 11 and the magnitude of the rotation angle of the convex portion 12 and the wire locking plate 13 are equal to each other.
At this time, since the convex surface 12a slides on the receiving surfaces 16a and 16b, the convex surface 12a receives a frictional force corresponding to the normal force from the receiving surfaces 16a and 16b.

  The convex portion 12 and the wire locking plate 13 in the present embodiment constitute a moving member in which the end portions of the angle wires 19 </ b> A and 19 </ b> B are fixed and move with the tilt of the operation shaft 11.

For example, when the operating shaft 11 is tilted in the middle of the first direction X and the second direction Y, the wire locking plate 13 that locks the angle wire 19A or the angle wire 19B rotates around the point O. To do.
For this reason, one of the angle wires 19A (19B) is pulled to the proximal end side. Similarly, the other of the angle wires 19A (19B) is sent to the tip side.
As a result, the bending portion 4 is bent in the direction in which the angle wire 19A (19B) is pulled.
If there is a bending resistance of the bending portion 4 itself or a resistance due to contact with the subject or the like, a counter moment that resists tilting acts on the wire locking plate 13 due to the tension from the angle wire 19A (19B).
However, when the reaction moment is balanced with the moment of the frictional force from the receiving surfaces 16a and 16b, the convex portion 12 can be kept stationary.

In the bending operation of the conventional endoscope apparatus, the frictional force accompanying the operation is constant. Therefore, in order to maintain the bending state even when the operator removes the hand from the operation unit, the frictional force in the operation unit is It is necessary to match when the reaction moment from the part becomes maximum.
In this case, even when the bending amount is small and the reaction moment from the bending portion is small, the frictional force against the reaction moment when the bending amount is maximum acts, so that the operation load in the range where the bending amount is small increases. There's a problem.

In the present embodiment, the maximum frictional force generated in the tilting range of the operating shaft 11 is balanced with the reaction moment received from the angle wire 19A (19B) when the bending portion 4 is bent to the maximum extent, as in the prior art. Is set to a size that can be.
On the other hand, in the range where the tilt angle is small, the amount of bending of the bending portion 4 is small, so the reaction moment received from the angle wire 19A (19B) is also smaller. Therefore, in the present embodiment, the frictional force is reduced to the extent that it can resist the reaction moment received from the angle wire 19A (19B) in a range where the tilt angle is small.

Here, the frictional force that acts from the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, and 16CR when the operation shaft 11 is tilted will be described.
In the present embodiment, the frictional force increases according to the tilt angle by changing the contact area between the convex surface 12a and the second receiving members 16BL, 16BR, 16CL, 16CR.

FIG. 7 shows a state in which the first direction X (second direction Y) component in the tilt of the operation shaft 11 is tilted clockwise by an angle θ1 (where θ1 ≧ θth). θth is a tilt angle at which the outer edge 12d of the convex surface 12a (the edge portion where the convex surface 12a and the end surface 12c intersect) is in contact with the tip (lower end in the drawing) of the second receiving member 16BR (CL).
FIG. 8 shows a state in which the first direction X (second direction Y) component in the tilt of the operation shaft 11 is tilted clockwise by an angle θ2 (>θ1> θth).

As shown in FIG. 7, when the tilt angle θ1 is equal to or smaller than θth, the convex surface 12a is in contact with both the second receiving members 16BL (16CL) and 16BR (16CR).
For this reason, the contact area between the convex surface 12a and the second receiving member 16BL (16CL) increases due to the tilt, and the contact area between the convex surface 12a and the second receiving member 16BR (CR) decreases.
For example, as shown in FIG. 9, when the convex surface 12a is a hemispherical surface, the half-moon figure APB tilts by an angle θ1 about the point O and moves to a half-moon figure A′P′B ′. The length of the arc AA ′ is equal to the length of the arc BB ′. Since the arc AA ′ is proportional to the increasing contact area and the arc BB ′ is proportional to the decreasing contact area, the contact area does not increase or decrease.
On the convex surface 12a of the present embodiment, the D-shaped figure CPD tilts by θ1 and moves to the D-shaped figure C′P′D ′. At this time, since CA = C′A ′, CC ′ + C′A = C′A + AA ′. Therefore, CC ′ = AA ′. On the other hand, since DB = D′ B ′, DD ′ + D′ B = D′ B + BB ′. Therefore, DD ′ = BB ′.
Therefore, since CC ′ = DD ′, the increase or decrease in the contact area due to the tilt of θ1 is canceled out.

On the other hand, as shown in FIG. 10, when the tilt angle of the convex portion 12 is θ2, the convex surface 12a does not come into contact with the second receiving member 16BR (16CR), so the second increases as θ2 increases. The contact area with the receiving member 16BL (16CL) is increasing.
In the present embodiment, an elastic member made of rubber or elastomer is used as the second receiving members 16BL, 16BR, 16CL, 16CR, and the second receiving members 16BL, 16BR, 16CL, 16CR are pressed against the convex surface 12a by the leaf spring portion 14b. ing. For this reason, 2nd receiving member 16BL, 16BR, 16CL, 16CR which contacts the convex surface 12a receives a compressive force, and elastically deforms. As the contact area increases, the elastic restoring force of the second receiving members 16BL, 16BR, 16CL, and 16CR increases.
As a result, the convex surface 12a receives a larger vertical drag from the second receiving members 16BL, 16BR, 16CL, and 16CR that increase the contact area, and thus the frictional force increases.

According to the endoscope apparatus 1 of the present embodiment, when the tilt angle of the operation shaft 11 is equal to or smaller than θth, the convex surface 12a is constant with the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, and 16CR. The contact area of For this reason, even if the convex part 12 tilts, the frictional force which acts on the convex part 12 is constant.
When the tilt angle of the operation shaft 11 exceeds a certain value θth, the frictional force between the convex surface 12a and the first receiving member 16A does not change, but between the convex surface 12a and the second receiving members 16BL, 16BR, 16CL, 16CR. The overall contact area increases, and the frictional force acting on the convex portion 12 increases as the convex portion 12 tilts. This frictional force is set to such an extent that it can resist the counter-moment from the angle wire 19A (19B) that similarly increases by tilting. For this reason, even if the operator removes his / her hand from the operation shaft 11, the convex portion 12 and the wire locking plate 13 can maintain the position at the time of tilting.
Since the operator does not need to always apply an operating force in order to keep the bending state of the bending portion 4 constant, the operator can easily perform the bending operation.

  According to the endoscope apparatus 1 of the present embodiment, the position of the operation shaft 11 can be fixed by a frictional force without deteriorating operability when the bending amount of the bending portion 4 is small and even when the bending amount is large.

[First Modification]
Next, an endoscope apparatus according to a first modification of the first embodiment of the present invention will be described.
FIG. 11 is a schematic cross-sectional view illustrating the configuration of the main part of the operation unit of the endoscope apparatus according to the first modification of the first embodiment of the present invention.

As shown in FIG. 2, the endoscope apparatus 1A of the present modification includes an operation unit 6A instead of the operation unit 6 of the endoscope apparatus 1 in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

As shown in FIG. 11, the operation unit 6 </ b> A includes an operation unit body 10 </ b> A instead of the operation unit body 10 in the first embodiment.
The operation unit body 10A includes second receiving members 160B (receiving members, elastic members) instead of the second receiving members 16BL, 16BR, 16CL, and 16CR of the operation unit body 10 in the first embodiment.
The second receiving member 160B includes a receiving surface 160b instead of the receiving surfaces 16b of the second receiving members 16BL, 16BR, 16CL, and 16CR of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The receiving surface 160b is formed with a minute concavo-convex shape that further increases the resistance to the rotation of the convex surface 12a.
The minute concavo-convex shape is constituted by grooves and protrusions in which the concavo-convex is repeated in the rotation direction.

According to the endoscope apparatus 1A of the present modification, each second receiving member 160B includes the receiving surface 160b, so that the tilt angle increases from the second receiving member 160B as in the first embodiment. Increase friction force.
For this reason, according to the endoscope apparatus 1A, as in the first embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and even when the bending amount is large, the operation shaft 11 can be operated. The position can be fixed.
Furthermore, according to the endoscope apparatus 1A of the present modified example, each second receiving member 160B includes the receiving surface 160b, so that the second receiving member 160B is more frictional than the case where the receiving surface of the second receiving member is a smooth concave spherical surface. The power can be increased. For this reason, the change of the frictional force with respect to the change of the contact area can be further increased.

[Second Modification]
Next, an endoscope apparatus according to a second modification of the first embodiment of the present invention will be described.
FIG. 12 is a schematic cross-sectional view illustrating the configuration of the main part of the operation unit of the endoscope apparatus according to the second modification of the first embodiment of the present invention.

As shown in FIG. 2, the endoscope apparatus 1B according to the present modification includes an operation unit 6B instead of the operation unit 6 of the endoscope apparatus 1 in the first embodiment.
As illustrated in FIG. 12, the operation unit 6 </ b> B includes an operation unit body 10 </ b> B instead of the operation unit body 10 in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The operation unit body 10B includes a first receiving member 160A (receiving member, elastic member) instead of the first receiving member 16A of the operation unit body 10 in the first embodiment.
The first receiving member 160A is a plate member fixed to the upper part in the protruding direction of the plurality of supporting protrusions 161 protruding on the supporting plate part 14c at the outer edge portion. The first receiving member 160A is a member that is more easily elastically deformed than the support plate portion 14c. A receiving surface 160a that contacts the convex surface 12a is provided on the proximal end side of the first receiving member 160A.

The receiving surface 160a of the first receiving member 160A is disposed at a position where the distance from the point O is slightly shorter than R so that the convex portion 12 can be pressed.
The receiving surface 160a may be a flat surface or a curved surface such as a spherical surface. The receiving surface 160a is pressed against the convex surface 12a at the time of assembly, and is slightly bent toward the support plate portion 14c.
The receiving surface 160a may be composed of a rough surface in order to increase the frictional force.
The receiving surface 160a may have a fine uneven shape in order to increase the frictional force.

  The material of the first receiving member 160A is not particularly limited as long as it can generate an appropriate frictional force with the convex surface 12a. For example, as the material of the first receiving member 160A, any one of metal, resin, rubber, and elastomer, or a material in which these are appropriately combined can be employed.

  The configuration of the endoscope apparatus 1B according to the present modification is the same as that of the first embodiment except that the first receiving member 16A of the first embodiment is replaced with a first receiving member 160A made of a thin plate member. This is the same as the endoscope apparatus 1 of FIG. For this reason, as in the first embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and the position of the operation shaft 11 can be fixed even when the bending amount is large.

[Third Modification]
Next, an endoscope apparatus according to a third modification of the first embodiment of the present invention will be described.
FIG. 13 is a schematic cross-sectional view illustrating the configuration of the main part of the operation unit of the endoscope apparatus according to the third modified example of the first embodiment of the present invention.

As shown in FIG. 1, an endoscope apparatus 1C according to this modification includes an operation unit 6C instead of the operation unit 6 of the endoscope apparatus 1 in the first embodiment.
As shown in FIG. 13, the operation unit 6 </ b> C includes an operation unit main body 20 instead of the operation unit main body 10 in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The operation unit main body 20 includes a convex portion 22 (moving member) instead of the convex portion 12 of the operation unit main body 10 in the first embodiment.
The convex portion 22 has a central surface 22a that is a convex spherical surface having a radius R in a region around the apex P that contacts the first receiving member 16A when the operation shaft 11 is tilted. The center surface 22a always contacts the entire receiving surface 16a when the operation shaft 11 is tilted.

When the convex portion 22 and the operation shaft 11 are tilted, the outer peripheral surface that is a convex spherical surface having a radius R1 (where R1 <R) is provided in the outer peripheral region that can come into contact with the second receiving members 16BL, 16BR, 16CL, and 16CR. 22b is formed.
Correspondingly, the second receiving members 16BL, 16BR, 16CL, and 16CR in the present modification include a receiving surface 26b made of a concave spherical surface having a radius R1, instead of the receiving surface 16b.

The receiving surface 26b is disposed so as to protrude radially inward from the spherical surface having the radius R1 with the point O as the center.
A step portion 22c is formed at the boundary between the central portion surface 22a and the outer peripheral portion surface 22b.
The step portion 22c may be provided at a position where it contacts the second receiving members 16BL, 16BR, 16CL, 16CR when the convex portion 22 rotates by a predetermined angle. In this case, the step portion 22 c has a stopper function that restricts the rotation of the convex portion 22 and the tilt of the operation shaft 11.

The configuration of the endoscope apparatus 1C according to the present modification is the above-described first except that the outer peripheral surface 22b of the convex portion 22 is a contact partner with respect to the second receiving members 16BL, 16BR, 16CL, and 16CR. This is the same as the endoscope apparatus 1 of the embodiment. For this reason, as in the first embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and the position of the operation shaft 11 can be fixed even when the bending amount is large.
In particular, according to the present modification, the distance between the outer peripheral surface 22b and the receiving surfaces 26b of the second receiving members 16BL, 16BR, 16CL, and 16CR and the point O is R1 shorter than R. The size in the direction perpendicular to the central axis Z can be reduced and the size can be reduced.
Furthermore, according to the present modification, the step portion 22c can be used as a stopper that restricts tilting, so that the operator cannot perform an excessive bending operation on the bending portion 4.

[Fourth Modification]
Next, an endoscope apparatus according to a fourth modification of the first embodiment of the present invention will be described.
FIG. 14 is a schematic cross-sectional view illustrating the configuration of the main part of the operation unit of the endoscope apparatus according to the fourth modified example of the first embodiment of the present invention. 15 is a cross-sectional view taken along the line DD in FIG.

As shown in FIG. 1, an endoscope apparatus 1D according to the present modification includes an operation unit 6D instead of the operation unit 6 of the endoscope apparatus 1 in the first embodiment.
As shown in FIG. 14, the operation unit 6 </ b> D includes an operation unit main body 30 instead of the operation unit main body 10 in the endoscope apparatus 1 in the first embodiment.
The operation unit main body 30 has a support frame 34, a convex part 32 (moving member), a wire, instead of the support frame 14, the convex part 12, and the wire locking plate 13 of the operation part main body 10 in the first embodiment. A locking plate 33 (moving member) is provided.
Hereinafter, a description will be given centering on differences from the first embodiment.

As shown in FIG. 15, the support frame 34 includes a support plate portion 34c and a hole portion 34d instead of the support plate portion 14c and the hole portion 14d in the first embodiment.
The support plate portion 34c is provided perpendicularly to the central axis Z between the side surfaces of the support plate portion 14c facing each other in the first direction X and the second direction Y, whereas the plan view of the support frame 34 is provided. Are provided so as to be orthogonal to the central axis Z in the diagonal direction.
For this reason, between the center part of the support plate part 34c and the side surface in the 1st direction X and the 2nd direction Y of the support frame 34, planarly substantially trapezoidal hole 34d penetrates in the plate | board thickness direction. .

As shown in FIG. 14, the convex part 32 is different from the convex part 12 in that four wire insertion holes 32c through which the angle wires 19A and 19B are inserted penetrate in the thickness direction.
As shown in FIG. 15, each wire insertion hole 32 c is provided in two places facing the first direction X across the center axis Z and two places facing the second direction Y across the center axis Z. It has been.

As shown in FIG. 15, the wire locking plate 33 is a disc having the same diameter as the outer diameter of the convex portion 32, and is fixed to the end surface 12 b of the convex portion 32.
Inside the wire locking plate 33, the base end portions of the angle wires 19 </ b> A and 19 </ b> B are locked at the position overlapping the wire insertion hole 32 c of the convex portion 32 in the same manner as in the first embodiment. In this modification, as an example, a locking member 13d connected to the angle wires 19A and 19B is locked in a through hole provided in the wire locking plate 33.

As shown in FIG. 14, the angle wires 19 </ b> A are locked at the locking positions of the wire locking plates 33 facing in the first direction X across the central axis S, respectively. An angle wire 19A is inserted through the wire insertion hole 32c facing the first direction X across the central axis S.
Although not particularly illustrated, the angle wires 19B are locked at the locking positions of the wire locking plates 33 facing the second direction Y across the central axis S, respectively. An angle wire 19B is inserted into the wire insertion hole 32c facing the second direction Y across the central axis Z.

  The angle wires 19A and 19B extending from the wire insertion holes 32c to the distal end side are respectively inserted into the coil sheath 126 (not shown) through the hole 34d, and the distal end 3 is the same as that in the first embodiment. It is extended to the locking position.

The configuration of the endoscope apparatus 1D according to the present modification is the same as that of the first embodiment except for the locking positions of the base ends of the angle wires 19A and 19B and the insertion positions of the angle wires 19A and 19B with respect to the convex surface 12a. The same as the mirror device 1. For this reason, as in the first embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and the position of the operation shaft 11 can be fixed even when the bending amount is large.
In particular, according to this modification, the angle wires 19A and 19B locked to the wire locking plate 33 are inserted into the wire insertion holes 32c of the convex portion 32, so that the angle wires 19A and 19B are It can be inserted into the inner area.
For this reason, the base ends of the angle wires 19A and 19B can be locked between the second receiving members 16BL and 16BR facing the central axis Z and between the second receiving members 16CL and 16CR. As a result, a frictional force can be generated on the same acting surface as the reaction surface of the counter-moment due to the tension of the angle wires 19A and 19B, so that the frictional force acts efficiently and the tilt position can be easily held.

[Second Embodiment]
An endoscope apparatus according to a second embodiment of the present invention will be described.
FIG. 16 is a schematic cross-sectional view showing the configuration of the main part of the operation unit of the endoscope apparatus according to the second embodiment of the present invention.

As shown in FIG. 1, an endoscope apparatus 1E according to the present embodiment includes an operation unit 6E instead of the operation unit 6 according to the first embodiment.
As shown in FIG. 16, the operation unit 6 </ b> E includes an operation unit main body 40 instead of the operation unit main body 10 in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

  The operation unit main body 40 is replaced with the support frame 44, the convex portion 12, the operation shaft 11, the second receiving members 16BL, 16BR, 16CL, and 16CR of the operation unit main body 10 in the first embodiment. It includes a flange-shaped member 42 (moving member), an operation shaft 41, and a receiving member 46, and is configured by removing the first receiving member 16A, the support plate 17, and the rotating shaft 18.

The support frame 44 includes a support plate portion 44c and a side surface portion 44b instead of the support plate portion 14c and the leaf spring portion 14b of the support frame 14 in the first embodiment.
The support plate portion 44 c is a plate-like portion in which four wire insertion holes 44 d through which the angle wires 19 </ b> A and 19 </ b> B are inserted are formed and the outer peripheral portion is fixed to the inner peripheral surface of the support frame 44.
The side surface portion 44b includes four side surfaces that face each other across the central axis Z of the support frame 44 between the first side surface 14A of the support frame 44 and the support plate portion 44c.
The side surface portion 44b may be formed in a plate shape having no opening portion, or an appropriate opening portion may be provided in a region excluding the vicinity of the support plate portion 44c.
In this embodiment, the side part 44b is formed in the plate shape which does not have an opening part as an example.
Although illustration is omitted, the configuration of the base end side of the support frame 44 is the same as that of the support frame 14 in the first embodiment.

The bowl-shaped member 42 is a bowl-shaped member having a shape obtained by partially cutting a complete spherical shell having an outer radius R so that the height is T (where T> R). .
The bowl-shaped member 42 includes an outer peripheral surface 42a made of a convex spherical surface having a radius R, an inner peripheral surface 42b made of a concave spherical surface having a smaller diameter than the radius R, and an end surface 42c.
The end surface 42c is formed on a straight line that passes through the center of the outer peripheral surface 42a and intersects the central axis b at an acute angle φ in a cross section including the central axis b of the bowl-shaped member 42.
Here, the acute angle φ is φ = arccos {(TR) / R}.
As the material of the flange-shaped member 42, the same material as that of the convex portion 12 can be adopted.

The operation shaft 41 includes a spherical portion 41c having a diameter larger than the shaft diameter of the shaft portion 11b at the end of the shaft portion 11b opposite to the operation head 11a, and the tilt shaft of the operation shaft 11 of the first embodiment. 11c is deleted.
The spherical center of the spherical portion 41c is located on the central axis S of the shaft portion 11b.
The length of the shaft portion 11b of the present embodiment is an appropriate value larger than R. The length of the shaft portion 11b of the present embodiment may be, for example, not less than 2 times and not more than 3 times R.

The operation shaft 41 is fixed to the hook-shaped member 42 with the shaft portion 11 b penetrating the top of the hook-shaped member 42.
The operation shaft 41 is fixed to the flange-shaped member 42 in such a manner that the central axis S of the shaft portion 11b is coaxial with the central axis b of the flange-shaped member 42 and the center of the spherical portion 41c is the outer peripheral surface 42a of the flange-shaped member 42. It is a position that is concentric with the center of.

The operation shaft 41 to which the flange-like member 42 is fixed is accommodated between the support plate portion 44 c and the base end (the upper end portion in the drawing) of the support frame 44. A part of the shaft portion 11b of the operation shaft 41 and the operation head 11a protrude from the base end side of the support frame 44 from the support plate portion 14c.
The spherical portion 41c of the operation shaft 41 is rotatably engaged with a bearing portion 43 disposed at the center portion of the support plate portion 44c.
The bearing portion 43 has a bearing surface 43a formed of a concave spherical surface having a diameter slightly larger than the outer diameter of the spherical portion 41c. The bearing surface 43a supports the spherical portion 41c of the operation shaft 41 so as to be rotatable about the point O on the central axis Z of the support frame 44.
With such a configuration, the operation shaft 41 is supported so as to be tiltable with respect to the central axis Z around the point O. The shaft portion 11 b of the operation shaft 41 can tilt in an arbitrary direction that intersects the central axis Z in a plan view along the central axis Z.
The state in which the central axis S of the shaft portion 11b is coaxial with the central axis Z is a neutral state of the shaft portion 11b in tilting.

The receiving member 46 is a member that contacts the outer peripheral surface 42a in the vicinity of the end surface 42c of the flange-shaped member 42 when the operation shaft 41 is in a neutral state. The receiving member 46 slidably contacts the outer peripheral surface 42a.
The receiving member 46 includes a receiving surface 46a formed of a concave spherical surface with a radius R that protrudes radially inward from a spherical surface with a radius R centered on the point O.
The receiving surface 46a of the receiving member 46 may be continuously formed in an annular range in plan view with the central axis Z as the center, or may be formed at a plurality of locations separated from each other in the circumferential direction with respect to the central axis Z. It may be.
In the present embodiment, as an example, the receiving surface 46a of the receiving member 46 is continuously formed in an annular range in plan view with the central axis Z as the center.

When the shaft portion 11b tilts with respect to the central axis Z, the receiving surface 46a is formed in a range where the contact state is different between the outer peripheral surface 42a in the tilting direction and the outer peripheral surface 42a opposite to the tilting direction.
The receiving surface 46a contacts the end portion of the outer peripheral surface 42a in the tilting direction in the entire tilting range. On the other hand, the receiving surface 46a is formed in such a range that the tilting angle is in contact with the end of the outer peripheral surface 42a on the opposite side in the tilting direction from 0 to a certain threshold value θth and does not contact when the tilting angle exceeds the threshold value θth. The
That is, on the plane including the central axis Z, the outer edge of the outer peripheral surface 42a in the neutral state is represented as a point e, the most proximal point on the receiving surface 46a is represented as a point f, and the most distal point is represented as a point g. = Θth and ∠eOg = θmax. Here, θmax is the maximum value of the tilt angle of the shaft portion 11b.
In the present embodiment, the material of the receiving member 46 is an elastic member similar to the second receiving members 16BL, 16BR, 16CL, and 16CR in the first embodiment.

In the operation portion main body 40, the base end portions of the angle wires 19 </ b> A and 19 </ b> B are locked by a locking member 45 in the vicinity of the end surface 42 c on the inner peripheral surface 42 b of the flange-shaped member 42.
The angle wire 19A is locked at a position facing in the first direction X across the central axis Z. The angle wire 19B is locked at a position facing in the first direction Y across the central axis Z.
Each angle wire 19A, 19B extends along the receiving surface 46a, and penetrates the wire insertion hole 44d.
Although illustration is omitted, the arrangement of the angle wires 19A and 19B on the tip side of the wire insertion hole 44d is the same as that in the first embodiment.
Each angle wire 19A, 19B is given an initial tension at the time of assembly so that no slack occurs in each angle wire 19A, 19B.

The operation of the endoscope apparatus 1E of the present embodiment will be described focusing on the operation related to the bending operation of the bending unit 4 using the operation unit 6E.
In the endoscope apparatus 1E, in order to bend the bending portion 4, the operator operates the operation shaft 41 of the operation portion 6E.
The operation shaft 41 is in a neutral state as shown in FIG. 16 before the operation is started. In the neutral state, the central axis S of the operating shaft 41 is coaxial with the central axis Z of the operating portion 6E.

When the operator applies a force to the operation head 11a of the operation shaft 41 in the direction intersecting the central axis S, the operation shaft 41 is supported by the bearing portion 43 so as to be tiltable about the point O. Tilt in the direction that the force acts.
For this reason, the hook-like member 42 fixed to the shaft portion 11b rotates around the point O.
For example, when the operation shaft 41 is tilted clockwise in the figure in FIG. 16 and the hook-shaped member 42 is rotated in the clockwise direction in the figure, the angle wire 19A (19B) on the opposite side (left side in the figure) is tilted. Pulled to the end side, the angle wire 19A (19B) in the tilting direction (right side in the figure) is sent out to the tip side.
For this reason, the bending part 4 is curved similarly to 1st Embodiment.

At this time, when the tilt angle is 0 ° or more and θth or less, the contact area that increases in the tilt direction cancels out the contact area that decreases on the opposite side of the tilt direction, so the outer peripheral surface 42a of the bowl-shaped member 42 and the receiving member The contact area of 46 with the receiving surface 46a is kept constant. Therefore, the frictional resistance that acts on the bowl-shaped member 42 from the receiving member 46 is constant.
When the tilt angle exceeds θth, the outer peripheral surface 42a opposite to the tilt direction is separated from the receiving surface 46a. Therefore, as the tilt angle increases, the contact area between the outer peripheral surface 42a and the receiving surface 46a in the tilt direction is monotonous. To increase.
In the present embodiment, since the receiving member 46 made of an elastic member presses the flange-shaped member 42, the frictional force increases as the contact area increases.

According to the endoscope apparatus 1E of the present embodiment, a relatively small constant frictional force is provided between the receiving member 46 and the bowl-shaped member 42 while the tilt angle where the bending amount of the bending portion 4 is small is equal to or smaller than θth. Act. For this reason, it is possible to resist the relatively small reaction moment acting from the angle wires 19A and 19B with a frictional force, and the stop position of the operation shaft 41 can be maintained.
On the other hand, when the tilt angle exceeds θth and the bending amount of the bending portion 4 increases, the frictional force acting between the receiving member 46 and the bowl-shaped member 42 increases, so that the countermoment is resisted by the frictional force. The stop position of the operation shaft 41 can be maintained.
Thus, according to the endoscope apparatus 1E, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and the position of the operation shaft 41 can be fixed even when the bending amount is large.

  Furthermore, according to the endoscope apparatus 1E of the present embodiment, when the angle wires 19A and 19B are towed, the frictional force due to the contact of the angle wires 19A and 19B with the receiving member 46 is also applied. Easy to fix the position.

[Third Embodiment]
An endoscope apparatus according to a third embodiment of the present invention will be described.
FIG. 17 is a schematic cross-sectional view showing the configuration of the main part of the operation unit of the endoscope apparatus according to the third embodiment of the present invention.

As shown in FIG. 1, the endoscope apparatus 1F of the present embodiment includes an operation unit 6F instead of the operation unit 6 of the first embodiment.
As shown in FIG. 17, the operation unit 6 </ b> F includes an operation unit body 50 instead of the operation unit body 10 in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

  The operation unit main body 50 is replaced with the support frame 54, the convex portion 12, the operation shaft 11, and the second receiving members 16BL, 16BR, 16CL, and 16CR of the operation unit main body 10 in the first embodiment. The first moving part 52A (moving member), the second moving part 52B (moving member), the operation shaft 51, and the receiving member 56 are provided, and the first receiving member 16A, the support plate 17, and the rotating shaft 18 are omitted. .

The support frame 54 includes a side surface portion 54b instead of the leaf spring portion 14b of the support frame 14 in the first embodiment, and is configured by removing the support plate portion 14c.
The side surface portion 54b includes four side surfaces that face each other with the central axis Z of the support frame 54 interposed therebetween.
The side part 54b may be formed in the plate shape which does not have an opening part, and the appropriate opening part may be provided.
In this embodiment, the side part 54b is formed in the plate shape which does not have an opening part as an example.
Although illustration is omitted, the configuration of the base end side of the support frame 54 is the same as that of the support frame 14 in the first embodiment.

The first moving part 52A is a bowl-shaped member having a shape obtained by cutting a complete spherical shell having an outer radius R in a plane so that the height is Ha (however, Ha <R).
52 A of 1st moving parts are provided with the outer peripheral surface 52a which consists of a convex spherical surface of radius R, and the end surface 52c from which the distance from the vertex Pa of the outer peripheral surface 52a becomes Ha.
A wire locking plate 53 (moving member) that is a disc having the same diameter as the outer diameter of the first moving portion 52A is fixed to the end surface 52c.
Angle wires 19 </ b> A and 19 </ b> B are locked to the wire locking plate 53 at positions that divide the circumferential direction into four equal parts in an annular region in plan view that overlaps the end surface 52 c.
A pair of angle wires 19A are locked in a first direction across the central axis b1 of the first moving part 52A. A pair of angle wires 19B are locked in a second direction perpendicular to the first direction across the central axis b1 of the first moving part 52A.
Each angle wire 19A, 19B is inserted into the first moving part 52A, and from the opening part 52e opened on the circumference surrounding the apex Pa on the outer peripheral surface 52a to the distal end side (lower side in the figure) of the support frame 54. It is extended toward.
Although illustration is omitted, the arrangement of the angle wires 19A and 19B on the tip side of the opening 52e is the same as that in the first embodiment.
Each angle wire 19A, 19B is given an initial tension at the time of assembly so that no slack occurs in each angle wire 19A, 19B.
As the material of the first moving part 52A, the same material as that of the convex part 12 can be adopted.

The second moving part 52B is a saddle-shaped member having a shape obtained by cutting a complete spherical shell having an outer radius R on a plane so that the height is Hb (where Hb <Ha).
The second moving unit 52B includes an outer peripheral surface 52b made of a convex spherical surface having a radius R, and an end surface 52d having a distance Hb from the apex Pb of the outer peripheral surface 52b.
As the material of the second moving part 52B, the same material as that of the convex part 12 can be adopted.

  The first moving unit 52A and the second moving unit 52B are fixed to the operation shaft 51 described later so that the central axes b1 and b2 are coaxial and the centers of curvature of the outer peripheral surfaces 52a and 52b are concentric.

The operation shaft 51 is configured by deleting the tilting shaft 11c of the operation shaft 11 of the first embodiment.
The length of the shaft portion 11b of the present embodiment is an appropriate value larger than twice R. The length of the shaft portion 11b of the present embodiment may be, for example, greater than 2 times R and less than 3 times.

In the shaft portion 11b of the operation shaft 51, the end opposite to the operation head 11a passes through the center portion of the wire locking plate 53 and is fixed to the inner peripheral surface on the back side of the apex Pa of the first moving portion 52A. ing. The central axis S of the shaft portion 11b of the operation shaft 51 and the central axis b1 of the first moving portion 52A. It is coaxial.
In the shaft portion 11b of the operation shaft 51, a second moving portion 52B is fixed to an intermediate portion of the shaft portion 11b. The central axis S of the shaft portion 11b of the operation shaft 51 and the central axis b2 of the second moving portion 52B are coaxial. The fixed position of the second moving portion 52B in the direction along the central axis S is such that the center of curvature of the outer peripheral surface 52b is the center of curvature of the outer peripheral surface 52a of the first moving portion 52A fixed to the shaft portion 11b on the central axis S. Is a concentric position.

The receiving member 56 is a member that is slidably in contact with the outer peripheral surfaces 52a and 52b of the first moving part 52A and the second moving part 52B fixed to the operation shaft 51.
In the support frame 54, the receiving member 56 is fixed to the outer peripheral portion of the upper opening 14a and the side portions 54b on the base end side (the upper side in the drawing).
The receiving member 56 includes a receiving surface 56a formed of a concave spherical surface with a radius R that protrudes radially inward from a spherical surface with a radius R centered on a point O on the central axis Z.
The receiving surface 56a of the receiving member 56 may be continuously formed in an annular range in plan view with the central axis Z as the center, or may be formed at a plurality of locations separated from each other in the circumferential direction with respect to the central axis Z. It may be.
In the present embodiment, as an example, the receiving surface 56a of the receiving member 56 is continuously formed in an annular range in plan view with the central axis Z as the center.

In the receiving surface 56a, a length ha (hereinafter referred to as a distal end side length ha) in a direction along the central axis Z from a plane passing through the point O and perpendicular to the central axis Z to an end on the distal end side is expressed by R-Ha. long.
In the receiving surface 56a, the length hb in the direction along the central axis Z from the plane passing through the point O and orthogonal to the central axis Z to the end on the base end side (hereinafter referred to as the base end side length hb) is R- Longer than Hb.
For this reason, as shown in FIG. 17, in the neutral state where the central axis S of the operation shaft 51 is coaxial with the central axis Z, the outer peripheral surfaces 52a and 52b are fixed distances ha + Ha−R and hb + Hb− from the end surfaces 52c and 52d, respectively. The range of R contacts the receiving surface 56a of the receiving member 56 in an annular shape.

The front end side length ha of the receiving surface 56a is set to a dimension such that the edge portion of the outer peripheral surface 52a intersecting the end surface 52c does not come off from the receiving surface 56a even when the shaft portion 11b is tilted by the maximum tilt angle θmax from the neutral state. To do.
The tip side length ha satisfies the following expression (1).

The base-side length hb of the receiving surface 56a is the outer peripheral surface that intersects the end surface 52d on the side opposite to the tilting direction when the shaft portion 11b tilts beyond the threshold θth (where 0 <θth <θmax) from the neutral state. The dimension is set such that the edge portion 52b is detached from the receiving surface 56a.
The tip side length hb satisfies the following expression (2).

  In the present embodiment, the material of the receiving member 56 is an elastic member similar to the second receiving members 16BL, 16BR, 16CL, and 16CR in the first embodiment.

With such a configuration, the first moving unit 52A and the second moving unit 52B are in a neutral state with respect to the outer peripheral surfaces 52a and 52b, both in the neutral state of the shaft portion 11b and in a state in which the shaft portion 11b is tilted with respect to the central axis Z. The receiving member 56 is in contact while being pressed radially inward. For this reason, since the first moving unit 52A and the second moving unit 52B rotate along the receiving surface 56a, the first moving unit 52A and the second moving unit 52B are held rotatably about the point O.
Accordingly, the first moving unit 52A, the second moving unit 52B, and the receiving member 56 have a function of a rotary joint that rotates around the point O. The receiving member 56 constrains the moving member composed of the first moving portion 52A, the second moving portion 52B, and the wire locking plate 53 so as to be rotatable around the point O.

A part of the second moving part 52B rotatably supported by the receiving member 56 is connected to the base end from the upper opening 14a in the support frame 54 together with the operating shaft 11 and the operating head 11a protruding from the second moving part 52B. Projects to the side (upper side in the figure).
Although not particularly illustrated, a part of the shaft portion 11b protruding from the second moving portion 52B and the operation head 11a pass through the opening portion 24a of the base end side exterior member 24 more proximally as in the first embodiment. Protruding.

The operation of the endoscope apparatus 1F according to the present embodiment will be described focusing on the operation related to the bending operation of the bending unit 4 using the operation unit 6F.
In the endoscope apparatus 1F, in order to bend the bending portion 4, the operator operates the operation shaft 51 of the operation portion 6F.
The operation shaft 51 is in a neutral state as shown in FIG. 17 before the operation is started. In the neutral state, the central axis S of the operation shaft 51 is coaxial with the central axis Z of the operation unit 6F.

When an operator applies a force to the operation head 11a of the operation shaft 51 in a direction intersecting the central axis S, the first moving unit 52A, the second moving unit 52B, and the receiving member 56 function as a rotary joint. Therefore, the operation shaft 51 tilts in the direction in which a force acts around the point O.
For this reason, the first moving part 52A and the second moving part 52B fixed to the shaft part 11b rotate around the point O.
For example, when the operating shaft 51 is tilted clockwise in the figure in FIG. 17 and the first moving part 52A and the second moving part 52B are rotated in the clockwise direction in the figure, the angle on the opposite side (left side in the figure) to the tilting direction. The wire 19A (19B) is pulled to the proximal end side, and the angle wire 19A (19B) in the tilting direction (right side in the drawing) is sent out to the distal end side.
For this reason, the bending part 4 is curved similarly to 1st Embodiment.

At this time, when the tilt angle is 0 ° or more and θth or less, in both the first moving unit 52A and the second moving unit 52B, there is a contact area that increases in the tilt direction and a contact area that decreases on the opposite side of the tilt direction. Offset. For this reason, the contact area between the outer peripheral surface 52a of the first moving part 52A and the receiving surface 56a of the receiving member 56 and the contact area between the outer peripheral surface 52b of the second moving part 52B and the receiving surface 56a of the receiving member 56 are constant. Kept. Accordingly, the frictional resistance acting on the first moving part 52A and the second moving part 52B from the receiving member 56 is constant.
When the tilt angle exceeds θth and is equal to or less than θmax, the contact area between the first moving unit 52A and the receiving member 56 is constant.
On the other hand, the contact area between the second moving portion 52B and the receiving member 56 is such that the outer peripheral surface 52a opposite to the tilting direction is away from the receiving surface 56a, so that the outer peripheral surface 52a and the receiving surface in the tilting direction increase as the tilt angle increases. The contact area with 66b increases monotonously.
In the present embodiment, since the receiving member 56 made of an elastic member presses the second moving portion 52B, the frictional force increases as the contact area increases.

According to the endoscope apparatus 1E of the present embodiment, while the tilt angle at which the bending amount of the bending portion 4 is small is equal to or smaller than θth, between the receiving member 56 and the first moving portion 52A and the second moving portion 52B, A relatively small constant frictional force acts. For this reason, it is possible to resist the relatively small reaction moment acting from the angle wires 19A and 19B with the frictional force, and the stop position of the operation shaft 51 can be maintained.
On the other hand, when the tilt angle exceeds θth and the bending amount of the bending portion 4 increases, the frictional force acting between the receiving member 56 and the second moving portion 52B increases, so that the reaction moment that increases as the bending amount increases. Can be resisted by a frictional force, and the stop position of the operation shaft 51 can be maintained.
Thus, according to the endoscope apparatus 1F, similarly to the second embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and the operation is performed even when the bending amount is large. The position of the shaft 41 can be fixed.

Furthermore, according to the endoscope apparatus 1F of the present embodiment, the first moving unit 52A, the second moving unit 52B, and the receiving member 56 have a function of a rotary joint that rotates around the point O.
Therefore, for example, it is not necessary to provide a rotation support mechanism such as the support plate 17 and the rotation shaft 18 in the first embodiment or the bearing portion 43 in the second embodiment. The structure of 1F becomes simple and manufacture becomes easy.

[Fourth Embodiment]
An endoscope apparatus according to a fourth embodiment of the present invention will be described.
FIG. 18 is a schematic cross-sectional view showing the configuration of the main part of the operation unit of the endoscope apparatus according to the fourth embodiment of the present invention.

As shown in FIG. 1, the endoscope apparatus 1G according to the present embodiment includes an operation unit 6G instead of the operation unit 6 according to the first embodiment.
As shown in FIG. 18, the operation unit 6 </ b> G includes an operation unit body 60 instead of the operation unit body 10 in the first embodiment.

The operation unit body 60 is replaced with the operation shaft 51 and the second receiving members 66BL, 66BR, and 66CL instead of the operation shaft 11 and the second receiving members 16BL, 16BR, 16CL, and 16CR of the operation unit body 10 in the first embodiment. , 66CR (receiving member, second receiving portion, elastic member), the support plate 17 and the rotating shaft 18 are deleted, and a second moving portion 52B (moving member) is added.
The operation shaft 51 and the second moving unit 52B have the same configuration as that of the third embodiment.
The following description will focus on differences from the first and third embodiments.

The second receiving members 66BL, 66BR, 66CL, 66CR are configured so that the receiving surface 16b of the second receiving member 16BL, 16BR, 16CL, 16CR of the first embodiment is the base of the receiving member 56 of the third embodiment. It is configured in place of the receiving surface 66b formed in the same arrangement position and shape as the receiving surface 56a in the range of the end side length hb.
Although not shown, the second receiving members 66BL, 66BR, 66CL, and 66CR are fixed to the leaf spring portion 14b in the same manner as the second receiving members 16BL, 16BR, 16CL, and 16CR of the first embodiment. Yes.
The material of the second receiving members 66BL, 66BR, 66CL, 66CR is an elastic member similar to the second receiving members 16BL, 16BR, 16CL, 16CR in the first embodiment.

With such a configuration, the convex surface 12a of the convex portion 12 and the outer peripheral surface 52b of the second moving portion 52B are arranged on a spherical surface with a radius R centered on the point O on the shaft portion 11b.
The convex surface 12a is pressed toward the point O by the receiving surface 16a of the first receiving member 16A as in the first embodiment.
The outer peripheral surface 52b is pressed toward the central axis Z by the receiving surfaces 66b of the second receiving members 66BL, 66BR, 66CL, and 66CR as in the third embodiment.
For this reason, the operation shaft 51 fixed to the convex portion 12 and the second moving portion 52B is supported to be tiltable about the point O.
Therefore, similarly to the third embodiment, the convex portion 12, the second moving portion 52B, the first receiving member 16A, and the second receiving members 66BL, 66BR, 66CL, 66CR rotate around the point O. Has the function of a rotary joint. The first receiving member 16A and the second receiving members 66BL, 66BR, 66CL, and 66CR can turn the moving member including the convex portion 12, the second moving portion 52B, and the wire locking plate 13 around the point O. Is restrained.

A constant frictional force acts on the convex surface 12a from the receiving surface 16a regardless of the tilt angle in the same manner as in the first embodiment.
As in the third embodiment, a constant frictional force is applied from the receiving surface 66b to the outer peripheral surface 52b when the tilt angle is 0 ° to θth, and when the tilt angle is θth to θmax, the tilt angle is As the value increases, the frictional force increases.

That is, the operation unit main body 60 in the present embodiment has the same function as that of the receiving member 56 in the third embodiment described above for the first receiving member 16A that contacts the convex portion 12 and the second that contacts the second moving unit 52B. The receiving members 66BL, 66BR, 66CL, and 66CR are separated.
Therefore, in the operation unit main body 60, the operation shaft 51 is the same as that of the third embodiment, except that the angle wires 19A and 19B are locked to the wire locking plate 13 as in the first embodiment. A tilting operation similar to that of the operation unit main body 50 is possible.
That is, according to the endoscope apparatus 1G of the present embodiment, the convex portion 12 and the second moving portion 52B are provided with the first receiving member 16A while the tilt angle at which the bending amount of the bending portion 4 is small is equal to or smaller than θth. A relatively small constant frictional force acts from the second receiving members 66BL, 66BR, 66CL, 66CR. For this reason, it is possible to resist the relatively small reaction moment acting from the angle wires 19A and 19B with the frictional force, and the stop position of the operation shaft 51 can be maintained.
On the other hand, when the tilt angle exceeds θth and the bending amount of the bending portion 4 increases, the frictional force acting between the second moving portion 52B and the second receiving members 66BL, 66BR, 66CL, 66CR increases, The counter-moment that increases as the amount increases can be resisted by a frictional force, and the stop position of the operation shaft 51 can be maintained.
Thus, according to the endoscope apparatus 1G, similarly to the third embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and the operation is performed even when the bending amount is large. The position of the shaft 41 can be fixed.

  The convex part 12 in this embodiment comprises the 1st moving part arrange | positioned on the opposite side to the operation edge part of an operating shaft. 16 A of 1st receiving members in this embodiment comprise the 1st receiving part which can contact a 1st moving part.

[Fifth Embodiment]
An endoscope apparatus according to a fifth embodiment of the present invention will be described.
FIG. 19 is an operation explanatory diagram of the operation unit of the endoscope apparatus according to the fifth embodiment of the present invention.

As shown in FIG. 1, an endoscope apparatus 1H according to this embodiment includes an operation unit 6H instead of the operation unit 6G according to the fourth embodiment.
The operation unit 6H includes an operation unit main body 70 instead of the operation unit main body 60 in the fourth embodiment, as shown in FIG.
The operation unit main body 70 includes the operation shaft 11 similar to that of the first embodiment, instead of the operation shaft 51 in the fourth embodiment. For this reason, although illustration is omitted, the support frame 14 in the present embodiment is provided with a support plate 17 and a rotating shaft 18 as in the first embodiment. In the present embodiment, the tilting shaft 11c of the operation shaft 11 is supported by the rotating shaft 18 as in the first embodiment.
However, the second moving part 52B in the present embodiment is eccentrically fixed to the base end side with respect to the fourth embodiment. The second moving portion 52B in the present embodiment is fixed to the shaft portion 11b so that the center of curvature of the outer peripheral surface 52b is a point O ′ that is decentered by Δ from the point O to the base end side on the center axis S. ing.
The following description will focus on differences from the first and fourth embodiments.

  In the present embodiment, the amount of eccentricity Δ of the second moving unit 52B is set to an amount by which the frictional force necessary to hold the stop position of the operation shaft 11 can be obtained in consideration of the amount of increase in frictional force due to the eccentricity described later. . However, in the present embodiment, as in the fourth embodiment, the effect of increasing the frictional force due to the change in the contact area is also obtained, so the eccentricity Δ does not have to be so large.

  The lengths of the second receiving members 66BL, 66BR, 66CL, 66CR in the present embodiment along the central axis Z are received on the side opposite to the tilting direction when the outer peripheral surface 52b of the eccentric second moving part 52B tilts by θth. The dimension is changed to be out of the surface 66b. The eccentric amount Δ of the second moving portion 52B generates a frictional force that can maintain the curved shape of the bending portion 4 against the force that the bending portion 4 tries to return even when the bending portion 4 is bent to the maximum extent. Set to the amount of eccentricity.

With this configuration, in the endoscope apparatus 1H according to the present embodiment, the operation shaft 11 is tilted about the point O by the support mechanism including the support plate 17 and the rotation shaft 18 as in the first embodiment. Supported as possible.
In the present embodiment, when the operator applies a force to the operation head 11a of the operation shaft 11 in the neutral state in a direction intersecting the central axis S, the convex portion 12 and the second moving portion 52B Rotate around the center. As a result, the shaft portion 11b tilts around the point O with respect to the central axis Z.

The frictional force received from the receiving surface 16a when the convex surface 12a of the convex portion 12 in the present embodiment tilts is constant regardless of the tilt angle of the shaft portion 11b, as in the fourth embodiment.
On the other hand, the second moving part 52B rotates around a point O shifted from the center of curvature O ′ of the outer peripheral surface 52b toward the tip side with the tilt of the shaft part 11b. For this reason, the rotation locus drawn by each point on the outer peripheral surface 52b is an arc drawing a rotation radius larger than the radius R.
Therefore, the outer peripheral surface 52b moves so as to bite into the second receiving members 66BL, 66BR, 66CL, and 66CR in the tilting direction as the tilting angle of the shaft portion 11b increases.
Since the leaf spring portion 14b bends in the pressing direction by this pressing, the elastic restoring force acts as a reaction force. As a result, the second receiving members 66BL, 66BR, 66CL, 66CR in the tilt direction are compressed by being sandwiched between the outer peripheral surface 52b and the leaf spring portion 14b. For this reason, the vertical drag acting on the outer peripheral surface 52b increases, and the frictional force acting on the outer peripheral surface 52b increases as the tilt angle increases.

Further, the second moving portion 52B of the present embodiment is substantially the same as the fourth embodiment with respect to the change in the contact area with the second receiving members 66BL, 66BR, 66CL, 66CR.
That is, when the tilt angle of the operation shaft 11 exceeds θth, the outer peripheral surface 52a opposite to the tilt direction is separated from the receiving surface 66b. Therefore, as the tilt angle increases, the outer peripheral surface 52b and the receiving surface 66b in the tilt direction The contact area increases monotonously.

As described above, according to the endoscope apparatus 1H, the change in the contact area between the second moving portion 52B and the second receiving members 66BL, 66BR, 66CL, 66CR is substantially the same as that in the fourth embodiment. .
Furthermore, according to the endoscope apparatus 1H of the present embodiment, the vertical from the second receiving members 66BL, 66BR, 66CL, 66CR acting on the second moving portion 52B arranged eccentrically with the tilting of the operation shaft 11. Even at the point where the drag increases with increasing tilt angle, the frictional force increases as the tilt angle increases.
For this reason, according to the endoscope apparatus 1H of the present embodiment, the operation shaft does not deteriorate when the bending amount of the bending portion 4 is small and the operability is deteriorated even when the bending amount is large. 11 positions can be fixed.

[Sixth Embodiment]
An endoscope apparatus according to a sixth embodiment of the present invention will be described.
FIG. 20 is a schematic perspective view illustrating the configuration of the main part of the operation unit of the endoscope apparatus according to the sixth embodiment of the present invention. 21 is a cross-sectional view taken along line EE in FIG.

As shown in FIG. 1, an endoscope apparatus 1J according to this embodiment includes an operation unit 6J instead of the operation unit 6G according to the fourth embodiment.
As shown in FIGS. 20 and 21, the operation unit 6 </ b> H includes an operation unit main body 80 instead of the operation unit main body 60 in the fourth embodiment.
The operation unit main body 80 includes a support frame 84, a wire locking plate instead of the support frame 14, the wire locking plate 13, the operation shaft 51, and the second receiving members 66BL, 66BR, 66CL, 66CR in the fourth embodiment. 83 (moving member), operating shaft 81, coil spring locking plate 82, second receiving member 86 (receiving member, second receiving portion, elastic member), the support plate 17 and the rotating shaft 18 are deleted, and the operating shaft A support portion 88 and a coil spring 87 (pressing member) are additionally provided.
The following description will focus on differences from the first and fourth embodiments.

As shown in FIG. 21, the support frame 84 has a first side surface 84A and a support plate portion 84c instead of the first side surface 14A, the support plate portion 14c, and the leaf spring portion 14b of the support frame 14 in the first embodiment. The side part 84b is provided.
The first side surface 84A includes an upper opening 14a in which the shaft portion 11b of the operation shaft 11 is movable on the first side surface 14A in the first embodiment, whereas the upper portion has a circular shape in plan view at the center. The difference from the first embodiment is that the opening 84a is formed.
The upper opening 84a is formed in a range surrounding the second moving part 52B protruding from the second receiving member 86 described later.

The support plate portion 84c is a plate-like portion having a cross shape in plan view having the same shape as the support plate portion 34c in the fourth modification of the first embodiment.
For this reason, between the center part of the support plate part 84c and each side part 84b mentioned later of the support frame 84, the hole part 84d of planar view substantially trapezoid shape has penetrated in the plate | board thickness direction.
As in the fourth embodiment, the first receiving member 16A is fixed to the center of the support plate portion 84c.
In the present embodiment, the receiving surface 16a of the first receiving member 16A is slightly pointed from a spherical surface having a radius R centered on the point O on the central axis Z in the support frame 84 in a state where the convex portion 12 is removed. It is arranged at a position protruding to the O side.

The side surface portion 84b includes four side surfaces that face each other across the central axis Z between the first side surface 84A of the support frame 84 and the support plate portion 84c.
The side surface portion 84b may be formed in a plate shape having no opening portion, or an appropriate opening portion may be provided in a region excluding the vicinity of the first side surface 84A.
In this embodiment, the side part 84b is formed in the plate shape which does not have an opening part as an example.
Although illustration is omitted, the configuration of the base end side of the support frame 84 is the same as that of the support frame 14 in the first embodiment.

The wire locking plate 83 is a plate member having a cross shape in plan view similar to the wire locking plate 13 of the first embodiment, and is fixed to the end surface 12 c of the convex portion 12.
However, the wire locking plate 83 has a pair of angle wires 19A facing the first direction X and a pair of angle wires 19B facing the second direction Y across the central axis Z of the support frame 84. The point which latches angle wire 19A, 19B differs from the wire latching plate 13 in the said 1st Embodiment.
Furthermore, the wire locking plate 83 is different from the wire locking plate 13 in the first embodiment in that an operation shaft support portion 88 (described later) is fixed to the surface on the base end side in the central portion.

Similar to the operation shaft 51 of the fourth embodiment, the operation shaft 81 is configured by deleting the tilting shaft 11c of the operation shaft 11 of the first embodiment. However, the operation shaft 81 is different from the operation shaft 51 in that the operation shaft 81 is not fixed to the convex portion 12 and has a shape obtained by cutting the shaft portion 11b of the operation shaft 51 slightly on the tip side from the position of the point O. .
Therefore, in the operation shaft 81, the central axis S of the shaft portion 11b and the central axis b2 of the second moving portion 52B are coaxial, and the spherical center of the outer peripheral surface 52a is located on the central axis S. This is the same as the operation shaft 51 of the fourth embodiment.

The coil spring locking plate 82 is a disk-like member that is fixed to the end surface 52d of the second moving part 52B and does not exceed the outer diameter of the second moving part 52B.
The coil spring locking plate 82 includes a through hole 82a through which the shaft portion 11b of the operation shaft 81 is inserted at the center. The coil spring locking plate 82 may include a through hole in addition to the through hole 82a, but at least an outer peripheral side of the through hole 82a includes a locking surface 82b for locking a coil spring 87 described later.

The second receiving member 86 is an elastic member having a ring shape in plan view, which has the same shape as the base end side length hb on the base end side is cut from the receiving member 56 in the third embodiment.
The material of the second receiving member 86 can be the same material as the receiving member 56 in the third embodiment.
The second receiving member 86 is fixed to the surface on the tip side of the first side surface 84A and the inner peripheral surface of each side surface portion 84b.
In the present embodiment, the receiving surface 86a of the second receiving member 86 is slightly more than the spherical surface of radius R centered on the point O on the central axis Z in the support frame 84 in a state where the second moving portion 52B is removed. It arrange | positions in the position which protrudes in the point O side.

The operation shaft support portion 88 is a cylindrical member having a slightly larger diameter than the shaft portion 11b of the operation shaft 81 and including a guide hole 88a into which the shaft portion 11b is slidably inserted.
The operation shaft support portion 88 is fixed to the central portion of the surface on the proximal end side of the wire locking plate 83. The central axis of the guide hole 88a is coaxial with the central axis s of the convex surface 12a.

  In the present embodiment, the shaft portion 11 b of the operation shaft 81 is inserted through the wire locking plate 83 into the guide hole 88 a of the operation shaft support portion 88 whose positional relationship with the convex portion 12 is fixed. At this time, the central axis s of the convex portion 12 and the central axis b2 of the second moving portion 52B are coaxial with each other. The wire locking plate 33 and the coil spring locking plate 82 fixed to the second moving part 52B face each other in the direction along the central axes s and b1.

The coil spring 87 is externally fitted to the operation shaft support portion 88 between the wire locking plate 83 and the coil spring locking plate 82 facing each other. One end of the coil spring 87 in the axial direction is locked to the proximal end surface of the wire locking plate 83. The other end of the coil spring 87 in the axial direction is locked to the front end surface of the coil spring locking plate 82.
The natural length of the coil spring 87 is longer than the distance between the wire locking plate 83 and the coil spring locking plate 82 when the convex surface 12a and the outer peripheral surface 52b are positioned on a sphere having a radius R.

As shown in FIG. 21, in the operation unit main body 80 having such a configuration, in the neutral state of the operation shaft 81, the central axis s of the convex portion 12 is coaxial with the central axis Z, and the convex surface of the convex portion 12 The central portion of 12a is in contact with the receiving surface 16a of the first receiving member 16A.
Further, the central axis b1 of the second moving part 52B is coaxial with the central axis Z. The outer peripheral surface 52b of the second moving part 52B is in contact with the receiving surface 86a of the second receiving member 86.
At this time, the coil spring 87 that is locked between the wire locking plate 83 and the coil spring locking plate 82 is compressed in the direction along the central axis Z. For this reason, the convex part 12 and the 2nd moving part 52B urged | biased by the elastic restoring force of the coil spring 87 press the receiving surfaces 16a and 86a to radial direction outer side, respectively.
On the contrary, the convex surface 12a and the outer peripheral surface 52b receive a reaction force toward the point O by the first receiving member 16A and the second receiving member 86, and therefore the spring force by the coil spring 87 and the first receiving member 16A and the second receiving surface 16b. By appropriately setting the balance with the elastic reaction force from the receiving member 86, the convex surface 12a and the outer peripheral surface 52b are supported at positions along a spherical surface having a radius R with the point O as the center.

  The convex portion 12, the second moving portion 52B, the first receiving member 16A, and the second receiving member 86 have a function of a rotary joint that rotates around the point O. 16 A of 1st receiving members and the 2nd receiving member 86 have restrained the moving member which consists of the convex-shaped part 12, the 2nd moving part 52B, and the wire latching plate 83 so that rotation around the point O is possible.

  According to the endoscope apparatus 1J having such a configuration, when the operator applies a force in the direction intersecting the central axis S to the operation head 11a of the operation shaft 81 in the neutral state, the convex portion 12 and The second moving unit 52B rotates around the point O. As a result, the shaft portion 11b tilts about the point O with respect to the central axis Z.

In the endoscope apparatus 1J of the present embodiment, in the endoscope apparatus 1G of the fourth embodiment, the distance between the convex portion 12 and the second moving portion 52B is fixed by the shaft portion 11b of the operation shaft 51. In contrast, the difference between the distance between the convex portion 12 and the second moving portion 52B can be changed by an external force component in the direction along the central axis S.
Therefore, when the tilt angle changes, the acting direction of the external force changes. Therefore, it is conceivable that the tilt center is slightly deviated from the point O by changing the balance of the external force. However, since the receiving surfaces 16a and 86a protrude slightly in the radial direction from the spherical surface with the radius R centered on the point O, there is no variation exceeding the protruding amount from each spherical surface.
Therefore, even if the tilt angle changes, the operation shaft 81 tilts about the point O.

  For this reason, according to the endoscope apparatus 1J, substantially the same as in the fourth embodiment, the operability is not deteriorated when the bending amount of the bending portion 4 is small, and even when the bending amount is large. 11 positions can be fixed.

In particular, in the case of this embodiment, the coil spring 87 urges the convex portion 12 and the second moving portion 52B radially outward, so that the convex surface 12a and the receiving surface 16a, and the outer peripheral surface 52b and the receiving surface 86a. The pressing force in between acts reliably. For this reason, a decrease in frictional force due to wear of the first receiving member 16A and the second receiving member 86 can be suppressed.
The convex surface 12a and the outer peripheral surface 52b are not spherical with a radius R, but may be an ellipsoid that tilts the shaft portion 11b and increases the radius R. At this time, the coil spring 87 may be tilted and the coil spring 87 may be compressed to increase the frictional force between the convex surface 12a and the first receiving member 16A and the outer peripheral surface 52b and the receiving surface 86a.

[Seventh Embodiment]
An endoscope apparatus according to a seventh embodiment of the present invention will be described.
FIG. 22 is a schematic cross-sectional view showing the configuration of the main part of the operation unit of the endoscope apparatus according to the seventh embodiment of the present invention. 23 is a cross-sectional view taken along line FF in FIG.

As shown in FIG. 1, the endoscope apparatus 1K according to the present embodiment includes an operation unit 6K instead of the operation unit 6 according to the first embodiment.
The operation unit 6K includes an operation unit body 90 instead of the operation unit body 10 in the first embodiment, as shown in FIGS.
The operation unit main body 90 includes a moving member 92 and a wire locking plate 93 instead of the convex portion 12 and the wire locking plate 13 in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The moving member 92 includes a curved plate portion 92A and a shaft-shaped portion 92B.
The curved plate portion 92A includes four curved plates 92b that extend in a cross shape from the central portion 92c and function as elastic springs.
The convex surface 92a of the curved plate 92b has a shape along a convex spherical surface or a convex spheroid that protrudes radially outward from the spherical surface of radius R inscribed in the apex Q in a natural state where no external force acts. Have.
For this reason, when an external force is applied to the curved plate 92b toward the radially inner side at the distal end portion in the protruding direction, the curved plate 92b undergoes flexural deformation and the radius of curvature decreases.
Hereinafter, the central axis passing through the apex Q of the curved plate portion 92A in the natural state is referred to as the central axis t.

  The surface 92a in the central portion 92c of the curved plate portion 92B is formed in a wider range than the receiving surface 16a of the first receiving member 16A with the apex Q as the center. The surface 92a in the center portion 92c has a size that does not come off the receiving surface 16a when the surface 92a moves relative to the receiving surface 16a of the first receiving member 16A due to tilting of the operation shaft 11 described later.

The ends in the extending direction of the curved plates 92b are slidably in contact with the receiving surfaces 16b of the second receiving members 16BL, 16BR, 16CL, and 16CR, similarly to the convex portion 12 of the first embodiment. To do. Since the end portions of the curved plates 92b in the extending direction press the second receiving members 16BL, 16BR, 16CL, and 16CR, the bending portions 92b are deformed by receiving a reaction force from the receiving surfaces 16b.
In the present embodiment, in such a deformed state, the surface 92a of each curved plate 92b has a shape (including a shape that perfectly follows) a spherical surface having a radius R.
Furthermore, the end surface 92e in the extending direction of each curved plate 92b has a position in the direction along the central axis t from the apex Q substantially equal to (equal to) the position of the end surface 12c of the convex portion 12 of the first embodiment. Including cases).

The width of each curved plate 92b in the direction orthogonal to the extending direction (hereinafter simply referred to as the width of the curved plate 92b) is the central axis t of the second receiving member 16BL, 16BR, 16CL, 16CR with which it contacts in the neutral state. It is larger than the circumferential width.
Furthermore, the width of each curved plate 92b is set so that the receiving surface 16b with which each of the curved plates 92b contacts at least the central axis t when moving relative to the second receiving members 16BL, 16BR, 16CL, 16CR by tilting the operation shaft 11 described later. It has a size covering in the circumferential direction.

The shaft portion 92B is made of a cylindrical or prismatic shaft member, and one end portion in the axial direction is fixed to the surface opposite to the surface 92a in the central portion 92c of the curved plate portion 92A. The central axis of the shaft-like portion 92B is coaxial with the central axis t of the curved plate portion 92A.
A fixing surface 92d for fixing a wire locking plate 93, which will be described later, is formed at the end of the axial portion 92B opposite to the curved plate portion 92A in the axial direction.
The fixed surface 92d is formed at a position where a later-described wire locking plate 93 can be disposed at a position less than the distance R from the apex Q. In the present embodiment, the position in the direction along the central axis t of the fixed surface 92d is, for example, closer to the apex Q than each end surface 92e of the curved plate 92b.

As shown by a two-dot chain line in FIG. 22, the wire locking plate 93 is a plate member having a cross shape in plan view similar to the wire locking plate 13 of the first embodiment.
The center portion of the wire locking plate 93 is fixed to the fixed surface 92 d of the shaft-like portion 92 </ b> B of the moving member 92.
An end portion of the wire locking plate 93 in the extending direction extends outward in the radial direction from the curved plate portion 92A through a gap between the adjacent curved plates 92b. Angle wires 19 </ b> A and 19 </ b> B are locked to the end in the extending direction of the wire locking plate 93 in the same manner as the wire locking plate 13 of the first embodiment.

  At the center of the wire locking plate 93, the central axis t of the curved plate portion 92A and the central axis S of the shaft portion 11b are coaxial, from the point O where the shaft portion 11b is supported to the apex Q of the curved plate portion 92A. The shaft portion 11b of the operation shaft 11 is fixed so that the distance becomes R.

With this configuration, the endoscope apparatus 1K according to the present embodiment can perform the bending operation of the bending portion 4 when the operator tilts the operation shaft 11 as in the first embodiment.
As described above, in the present embodiment, since the size of the central portion 92c and the width of each curved plate 92b in the curved plate portion 92A are sufficiently large, the surface 92a has a cross shape in plan view. There is no particular effect on the change of the contact area.
On the other hand, the end surface 92e of the curved plate portion 92A is provided at the same position as the end surface 12c of the convex portion 12 in the first embodiment.
Therefore, the change in the contact area between the surface 92a of the curved plate portion 92A and the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, and 16CR at the time of tilting is exactly the same as in the first embodiment. It is the same.

In the first embodiment, the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, and 16CR are convex surfaces 12a that are convex spherical surfaces with a radius R that move on a spherical surface with a radius R centered on the point O. Contact with. For this reason, the frictional force acting from the receiving surfaces 16a and 16b is proportional to the contact area.
On the other hand, in the present embodiment, the first receiving member 16A, the second receiving members 16BL, 16BR, 16CL, and 16CR are in contact with the surface 92a that protrudes radially outward from the spherical surface having the radius R around the point O in the natural state. To do.
For this reason, the surface 92a of the curved plate portion 92A presses the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, and 16CR as contact partners. The surface 92a moves on a curved surface determined by the balance of forces with the first receiving member 16A and the second receiving members 16BL, 16BR, 16CL, and 16CR as contact partners. The curved surface on which the surface 92a moves is a curved surface that is substantially along the spherical surface having the radius R (including a case where the surface 92a is completely aligned).

Since the pressing force acting from the curved plate portion 92A increases toward the end in the extending direction of the curved plate 92b, in particular, the pressing force acting on the second receiving members 16BL, 16BR, 16CL, 16CR is the first embodiment. Increased compared to form.
For this reason, even if the change in the contact area is the same as in the first embodiment, the frictional force that the surface 92a receives from the receiving surface 16b is particularly greater than that in the first embodiment.

  For this reason, according to the endoscope apparatus 1K, as in the first embodiment, the operation axis does not deteriorate when the bending amount of the bending portion 4 is small, and even when the bending amount is large. 11 positions can be fixed.

In particular, in the case of the present embodiment, compared to the first embodiment, the frictional force can be increased by the contribution of the pressing force due to the bending deformation of the curved plate 92b. Even in this case, the position of the operation shaft 11 can be easily fixed.
Since the curved plate portion 92A of the moving member 92 can be formed by pressing a sheet metal, manufacturing is facilitated.

  In the above description of each embodiment and each modification, an example in which the bending operation of the bending portion 4 is performed by pulling the angle wire by the operation portion has been described. However, the wire pulled by each operation unit is not limited to the angle wire that bends the bending portion 4. For example, when the endoscope apparatus has a stand that can be operated by wire pulling, the endoscope apparatus may be used for an operation of changing the angle of the stand.

  In the description of each of the embodiments and the modifications described above, the bending portion 4 is bent in the biaxial direction, so that the four angle wires 19A and 19B are pulled. However, the bending portion may be bent only in one axial direction. In this case, while removing the pair of angle wires, the mechanism tilting in the independent biaxial direction can be replaced with a mechanism tilting only in the single axial direction.

In the above description of each embodiment and each modification, an example in which an elastic member is provided on at least one of the moving member and the receiving member has been described. However, the moving member and the receiving member do not need to be provided with an elastic member as long as the frictional force increases as the contact area increases on the contact surface.
For example, at least one of the moving member and the receiving member may have a different friction coefficient, and the contact with the region having a large friction coefficient may be increased as the contact area increases.
For example, the moving member and the receiving member may be provided with a pressing member whose mutual pressing force on the contact surface increases as the contact area increases.

In the description of each of the embodiments and the modifications described above, an example in which the entire receiving member is made of rubber or elastomer has been described. However, the receiving member may be configured to include an elastic member only in a portion serving as a receiving surface.
Further, the receiving member may be made of a composite material of a high-rigidity metal or resin and a resin, rubber, or elastomer that is a lower-rigidity elastic member, and the elastic member may be provided on a part of the receiving surface. For example, the receiving member can have a structure in which minute protrusions made of an elastic member such as rubber protrude from a smooth resin surface.

  In the above description of the first and fourth to seventh embodiments, the first receiving member 16A has been described as an example in which the point O is supported by the support plate portion whose position is fixed with respect to the support frame. However, the support plate portion may be configured to be able to bias the first receiving member 16A toward the moving member by elastic deformation. In this case, the first receiving member 16A is pressed by the moving member according to the elastic restoring force, whereby the frictional force acting on the moving member from the receiving surface 16a can be further increased.

In the first to sixth embodiments and the description of each embodiment, the example has been described in which the surface of the moving member that contacts the receiving member is a convex spherical surface.
However, the surface of the moving member protrudes outward in the radial direction from the spherical surface having the radius R inscribed in the apex in the natural state where no external force is applied, such as the natural state surface 92a in the seventh embodiment. The shape may be a convex spherical surface or a convex spheroidal surface.
The shape of the moving member in plan view can be appropriately selected depending on the shape and arrangement of the receiving member as the contact partner. For example, a cross shape similar to that of the seventh embodiment may be used. For example, the planar view shape of the moving member may be a radial shape other than a cross shape. Furthermore, the planar view shape of the moving member may be a shell shape without a cut in the circumferential direction.

In the first to sixth embodiments and the description of each embodiment, an example has been described in which the moving member has a bowl-like or shell-like shape formed by cutting a spherical shell.
However, the shape of the back side of the convex surface is not particularly limited as long as the moving member has a convex surface that slidably contacts the receiving surface of the receiving member.
That is, the moving member may have a convex shape formed by cutting a solid sphere.

In the description of the third embodiment, at the time of tilting, the contact area between the first moving portion 52A on the side opposite to the operation end portion and the receiving member 56 across the tilt center is constant, and the operation is performed across the tilt center. The example in the case where the contact area between the second moving part 52B on the end side and the receiving member 56 changes depending on the tilt angle has been described.
However, in the third embodiment, the contact area between the first moving part 52A and the receiving member 56 varies depending on the tilt angle, and the contact area between the second moving part 52B and the receiving member 56 is constant. Good.

In the description of the third embodiment, an example in which the receiving member 56 is in contact with the first moving unit 52A and the second moving unit 52B has been described. However, it is not essential that the first moving part 52A and the second moving part 52B come into contact with one receiving member 56.
For example, it is good also as a structure which provides separately the 1st receiving part which contacts 52 A of 1st moving parts, and the 2nd receiving part which contacts the 2nd moving part 52B.

In the description of each of the above-described embodiments and modifications, the friction force is constant when the tilt angle is equal to or smaller than the threshold θth, and when the tilt angle exceeds the threshold θth, the friction force increases as the tilt angle increases. explained.
However, it is not essential to keep the frictional force constant below the threshold θth. For example, the friction force may increase monotonously as the tilt angle increases from 0 °.

In the description of each of the embodiments and the modifications described above, an example in which the contact area is changed according to the tilt angle when the receiving member and the moving member are in contact with each other with continuous curved surfaces has been described. However, the contact area change rate may be changed by changing the areas of the contact portions of the receiving member and the moving member in the moving direction of the moving member.
Hereinafter, a receiving member used in the endoscope apparatus of the fifth modification example of the first embodiment of the present invention which is such a modification example will be described.
FIG. 24A is a schematic front view showing the configuration of the receiving member used in the endoscope apparatus of the fifth modified example of the first embodiment of the present invention. FIG. 24B is a G view in FIG.

This modification includes a second receiving member 116 shown in FIGS. 24A and 24B in place of the second receiving members 16BL, 16BR, 16CL, and 16CR of the first embodiment.
The second receiving member 116 is configured by forming a groove 116c on each receiving surface 16b in the second receiving member 16BL, 16BR, 16CL, 16CR of the first embodiment.
As shown in FIG. 24A, the groove 116c is configured by a plurality of elongated grooves in an isosceles triangle shape having a vertex on the base end side (the upper side in the figure) when viewed from the radial direction with respect to the central axis Z. A plurality of the grooves 116c are arranged in parallel along the circumferential direction with respect to the central axis Z. A plurality are formed.

  According to such a configuration, when the convex surface 12a comes into contact with the area where the groove 116c is formed, the contact area is reduced because the receiving surface 16b is missing in the area of the groove 116c. As a result, the magnitude of the frictional force from the receiving surface 16b changes according to the change in the contact area.

As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment and its modification. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention.
Further, the present invention is not limited by the above description, and is limited only by the appended claims.

1, 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1J, 1K Endoscopic device 2 Insertion section 4 Bending section 6, 6A, 6B, 6C, 6D, 6E, 6F, 6G, 6H, 6J , 6K Operation unit 10, 10A, 10B, 20, 30, 40, 50, 60, 70, 80, 90 Operation unit main body 11, 41, 51, 81 Operation shaft 11a Operation head (operation end)
12 Convex part (moving member, first moving part)
12a, convex surfaces 13, 33, 53, 83, 93 wire locking plate (moving member)
14b Leaf spring portions 16a, 16b, 26b, 46a, 56a, 66b, 86a, 160a, 160b Receiving surfaces 16A, 160A First receiving member (receiving member, first receiving portion, elastic member)
16BL, 16BR, 16CL, 16CR, 116, 160B Second receiving member (receiving member, elastic member)
19A, 19B Angle wire (wire)
22, 32, Convex part (moving member)
22a Center part surface 22b Outer peripheral part surface 22c Step part 42 Saddle-shaped member (moving member)
42a, 52a, 52b Outer peripheral surface 46, 56 Receiving member (elastic member)
52A 1st moving part (moving member)
52B 2nd moving part (moving member)
66BL, 66BR, 66CL, 66CR, 86 Second receiving member (receiving member, second receiving portion, elastic member)
87 Coil spring (pressing member)
88 Operation shaft support portion 92 Moving member 92A Curved plate portion 92a Surface Z Center axis (neutral axis)

Claims (5)

An endoscope apparatus that is operated by pulling a wire,
An operating shaft supported to be tiltable with respect to the neutral axis;
A moving member in which an end of the wire is fixed and moves with tilting of the operation shaft;
A receiving member with which the moving member is slidably contacted;
With
When the tilt angle of the operation shaft with respect to the neutral axis exceeds a certain value, the contact area between the moving member and the receiving member increases as the tilt angle increases.
Endoscopic device. The receiving member is
A plurality of receiving surfaces that can contact the moving member,
The endoscope apparatus according to claim 1, wherein when the tilt angle of the operation shaft exceeds a certain value, the number of the moving members and contact portions on the plurality of receiving surfaces changes. At least one of the receiving member and the moving member is made of an elastic member,
The vertical drag acting on the moving member from the receiving member is increased by increasing the amount of elastic deformation of the elastic member as the tilt angle of the operation shaft is increased. Endoscopic device. The receiving member is
The endoscope apparatus according to any one of claims 1 to 3, wherein the moving member is constrained to be rotatable around a single point. The moving member is
A first moving portion disposed on the opposite side of the operation end of the operation shaft from the tilting center of the operation shaft;
A second moving unit disposed closer to the operation end of the operation shaft than the tilting center of the operation shaft;
With
The receiving member is
A first receiving part capable of contacting the first moving part;
A second receiving part capable of contacting the second moving part;
The endoscope apparatus according to any one of claims 1 to 4, further comprising:

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