JP2002360505A - Flexible endoscope - Google Patents

Abstract

(57) [Summary] [Objective] In an endoscope in which the flexibility of a flexible tube is changed by changing the bending stiffness of a coil, an accidental inoperable state of the coil or a change in the coil and other built-in endoscopes is required. Prevent interference. In an endoscope provided with a flexible tube portion having flexibility in an insertion portion, a tube provided in the flexible tube portion, which is linear in a free state and changes bending rigidity by expansion and contraction in an axial direction. -Shaped coil body; a bottomed tubular coil storage tube surrounding the outer surface of the coil body, having a bottom surface in contact with one end of the coil body and an opening in which the other end of the coil body is located; A coil pressing member provided at an opening of the coil storage tube, the coil pressing member engaging with the coil body; and moving the coil pressing member in the forward and reverse directions in the axial direction of the coil body to form a bottom surface of the coil storage tube and the coil. A pressing member driving mechanism for changing the degree of compression of the coil body sandwiched between the pressing member and the pressing member;

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible endoscope capable of changing the flexibility of a flexible tube.

[0002]

2. Description of the Related Art Medical and industrial endoscopes are provided with a flexible tube at the insertion portion to facilitate insertion of a bent path into an observation object. However, in order to further improve the insertion workability, an endoscope of a type in which the flexibility (flexural rigidity, flexural hardness) of the flexible tube portion is made variable has been proposed. This type of endoscope, for example,
When the sigmoid colon is inserted into the large intestine, the flexible tube is hardened when passing through the sigmoid colon, and the flexible tube is softened after passing through the sigmoid colon.

As means for changing the flexibility of the flexible tube, for example, a coil having a straight cylindrical shape in a free state is inserted into the flexible tube, and the degree of compression of the coil is changed. Things are known. This kind of coil is hard to bend when compressed, and easy to bend when extended,
By changing the degree of compression of the coil, the flexibility of the flexible tube can be changed.

As a means for expanding and contracting a coil, there is known a method in which a wire to be pulled is inserted through the center of a cylindrical coil, and the tip of the wire is fixed to the tip of the coil. FIG. 7 schematically shows the conventional coil operation structure, in which a tubular coil 102 is provided in a flexible tube portion 101 of an endoscope 100. The base end of the coil 102 is connected to a stopper 10 fixed to the flexible tube 101.
3 and the tip is free with respect to the flexible tube 101. A coil pulling wire 104 is inserted through the center of the coil 102, and the coil pulling wire 10
The coil pressing portion 105 provided at the tip of
2 is fixed to the tip. The proximal end side of the coil pulling wire 104 projects from the coil 102 and is wound around a drum 106. The drum 106 is the rotation center shaft 1
07 is rotatably supported in the forward and reverse directions, and can be arbitrarily rotated from the outside of the endoscope via a driving mechanism including a drum gear 108 and the like. Drum 106
When the coil is rotated in the counterclockwise direction in FIG. 7, the coil pulling wire 104 is wound and pulled by the drum 106, and the coil pressing portion 105 pushes the tip of the coil 102. Then, the coil 1 whose base end is fixed to the stopper 103
02 is compressed to increase bending rigidity (harden),
As a result, the flexible tube portion 101 containing the coil 102 is hardened. When the drum 106 is rotated clockwise in FIG. 7 from the hardened state, the coil pulling wire 104 is relaxed and the compression of the coil 102 is released. When the coil 102 is extended to a free state, the bending stiffness is minimized.

In the above-described coil operation structure, a wire is used to control the degree of compression of the coil. However, when a tension is applied to the wire when it exceeds the limit of the tensile strength, or when the metal is used over time, When fatigue occurs, the wire may be cut. When the wire is cut, the flexibility of the flexible tube portion changes abruptly. For example, when such a sudden change in the flexibility occurs during clinical use of a medical endoscope, the recoil thereof damages the body cavity. There is a risk.

When the coil is compressed, a part of the coil may radially deviate from the center axis of the coil, that is, a so-called buckling may occur. When the coil buckles, some of the loop-shaped parts of the coil protrude in the radial direction and come into contact with or bite into another built-in endoscope, thereby damaging the built-in endoscope. There is a possibility.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide an endoscope in which the flexibility of a flexible tube is changed by changing the bending stiffness of a coil. An object of the present invention is to provide a flexible endoscope that does not cause interference.

[0008]

SUMMARY OF THE INVENTION The present invention for achieving the above objects has the following objects.
In an endoscope provided with a flexible tube portion having flexibility in an insertion portion, a cylindrical coil provided in the flexible tube portion, which is linear in a free state and changes bending rigidity by expansion and contraction in an axial direction. A bottomed tubular coil storage tube surrounding the outer surface of the coil body, having a bottom surface in contact with one end of the coil body and an opening in which the other end of the coil body is located; A coil pressing member provided in the opening of the coil member and engaging with the coil body;
And pressing the coil pressing member by moving the coil pressing member in the forward and reverse directions in the axial direction of the coil body to change the degree of compression of the coil body sandwiched between the bottom portion of the coil housing tube and the coil pressing member. A member driving mechanism;

As the pressing member driving mechanism, for example, a lead screw extending in the axial direction of the coil body and having a thread on the outer surface, a screw hole formed in the coil pressing member, into which the screw of the lead screw is screwed, A linear guide member that guides the coil pressing member straight in the axial direction of the coil body, and a lead screw is rotated in the forward and reverse directions, and the linearly guided coil pressing member advances and retreats in the axial direction of the coil body according to the screw and the screw hole. An embodiment provided with screw driving means can be provided.

In this case, the screw drive means can be a forward / reverse drive motor or a manually operated knob.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a flexible endoscope according to the present invention will be described with reference to FIGS. An electronic endoscope 10 shown in FIG. 1 is a medical endoscope, and has an insertion section 11 inserted into a body cavity and an operation section 12 connected to a base side thereof. The insertion portion 11 has a distal end portion 13, a bending portion 14, and a flexible tube portion 15 in this order from the distal end side.
2 connected.

The distal end portion 13 has a distal end main body (not shown) made of a rigid member. The distal end main body has an objective lens holding hole (not shown), a light distribution lens holding hole, an air / water channel outlet, and a treatment tool. An insertion channel outlet and the like are formed. An objective lens for imaging and a light distribution lens for illumination are held in the objective lens holding hole and the light distribution lens holding hole.

In the bending portion 14, there is provided a node ring assembly including a plurality of node rings (bending pieces) connected to be relatively rotatable. Bending operation knob 2 provided on operation unit 12
By rotating the 0A and 20B, a plurality of bending operation wires (not shown) are pulled or loosened to relatively rotate each node ring constituting the node ring assembly. Then, the bending portion 14 is bent. Specifically, when the bending operation knob 20A is turned in the forward and reverse directions, the bending portion 14 is bent in the left and right direction via a pair of bending operation wires, and when the bending operation knob 20B is turned in the forward and reverse directions. The bending portion 14 bends vertically through another pair of bending operation wires. Further, the bending state of the bending portion 14 is determined by the lock knob 21.
A can be fixed by operating A and the lock lever 21B.

From the operation unit 12, the universal tube 2
3 is extended, and a connector portion 24 for connecting to a processor (not shown) is provided at the end of the universal tube 23.
Is provided. The connector portion 24 is provided with an image signal transmission cable and an end portion of a light guide fiber bundle (not shown), an inlet portion of an air supply channel and a water supply channel, and the like. By connecting the connector portion 24 to a processor, These units are connected to an image processing device on the processor side, a light source, and an air / water supply source.

In the tip portion 13, there is a C behind the objective lens.
A CD is provided, and the image of the observation target, which has entered the light receiving surface of the CCD from the objective lens, is photoelectrically converted and transmitted via the aforementioned image signal transmission cable disposed from the CCD to the connector section 24 of the universal tube 23. And sent to the processor as an electronic image. In the processor, the electronic image can be displayed on a monitor or recorded on an image recording medium. The operation unit 12 is provided with a plurality of remote operation button switches 25 for performing remote operations related to image processing. Further, the light distribution lens is provided with illumination light from a light source provided in the processor via the above-described light guide fiber bundle disposed from the connector portion 24 of the universal tube 23 to the distal end portion 13.

The operation unit 12 is provided with an air / water button 26 near the remote operation button switch 25. When the air / water supply button 26 is pressed, the water supply source provided on the processor side communicates with the water supply channel provided in the endoscope, and water is supplied into the water supply channel. A nozzle is provided at the outlet of the water supply channel provided at the distal end portion 13 toward the objective lens. Liquid such as washing water sent to the water supply channel is ejected from the nozzle toward the objective lens, and the objective lens Wash. In addition, air / water button 2
6 is provided with a hole (not shown) on the upper surface, and when this hole is closed, the positive pressure of the air supply source provided on the processor side acts on the air supply channel in the endoscope, and the air supply channel is closed. Air is sent to the outlet. Like the water channel, the tip 1
At the outlet of the air supply channel provided in 3, a nozzle is provided toward the objective lens. When air is sent to the air supply channel, air is blown out from the nozzle toward the objective lens and adheres to the objective lens. It is possible to remove water droplets of the washed water and other liquids such as body fluid.

The connecting portion 16 of the electronic endoscope 10 is provided with a treatment instrument insertion port projection 27 for inserting a treatment instrument such as a forceps or a high frequency cautery treatment instrument. A treatment tool insertion channel 28 (FIG. 2) extends toward the inside of the endoscope. The treatment tool insertion channel 28 is connected to a treatment tool insertion channel outlet formed on the distal end portion 13, and the treatment tool inserted from the treatment tool insertion port projection 27 passes through the treatment tool insertion channel 28 and exits from the treatment tool insertion channel outlet. Can protrude. A suction tube 29 is connected to the treatment instrument insertion channel 28, and the suction tube 29 is connected to the electronic endoscope 1
0 is connected to a negative pressure source (suction source) (not shown) provided outside. Therefore, a treatment instrument such as forceps or a high-frequency cautery treatment instrument is inserted into the treatment instrument insertion channel 28 through the treatment instrument insertion port projection 27, and the suction tube 29 is inserted.
It is possible to apply a negative pressure from a negative pressure source via. When the treatment instrument insertion channel 28 is used as a treatment instrument insertion channel, the treatment instrument inserted via the treatment instrument insertion port projection 27 projects from the treatment instrument insertion channel outlet.
On the other hand, when the treatment tool insertion channel 28 is used as a suction conduit, the suction button 30 provided on the operation unit 12 is used.
Press. Then, the conduit on the negative pressure source side and the treatment instrument insertion channel are communicated, and the negative pressure is applied to the treatment instrument insertion channel 28.
And a fluid such as a body fluid can be sucked from the treatment instrument insertion channel outlet.

As described above, the bending portion 14 can be arbitrarily bent by operating the bending operation knobs 20A and 20B, and the flexible tube portion 15 also has flexibility. This curved part 1
4 and the above-mentioned internal components located in the flexible tube portion 15, namely, the treatment instrument insertion channel 28, the image signal transmission cable, the light guide fiber bundle, the air supply channel,
The water supply channel and the like have flexibility so as to respond to the bending operation of the bending portion 14 and the deformation of the flexible tube portion 15. In the electronic endoscope 10 according to the present embodiment, as described below,
It is possible to change the flexibility (flexural rigidity) of the flexible tube 15.

The flexible tube 15 is made of a flexible tube 3 having flexibility.
1 (FIG. 2) constitutes the outer shape. The flexible tube 31 has a structure in which the outermost portion is covered with a sheath made of polyurethane or the like, and a helical tube or the like for ensuring strength is overlapped on the inner side, and has non-permeability and constant bending rigidity. ing. A part of the flexible tube 31 on the proximal end side (the operation unit 12 side) is covered with a conical rubber stopper tube 32. A portion of the flexible tube 31 covered with the rubber tube 32 is a connecting portion 16 that is not inserted into the observation target.
The flexible tube 31 is restricted by the rubber tube 32 so as not to bend excessively.

As shown in FIG. 2, inside the flexible tube 31, in addition to the treatment instrument insertion channel 28 and the other built-in components described above, a coil (coil body) is arranged in the longitudinal direction of the flexible tube portion 15. ) 35 are arranged. The coil 35 formed by winding a steel wire has a straight cylindrical shape in a free state, and is extendable and contractible in the axial direction.

The coil 35 is housed inside a flexible tube (coil housing tube) 36 provided in the flexible tube portion 15. The flexible tube 36 is made of a flexible material such as a synthetic resin and the like.
8 (FIG. 2) is fixed in the endoscope main body on the operation unit 12 side. As shown in FIG. 4, the inner diameter of the flexible tube 36 is slightly larger than the outer diameter of the coil 35, and the coil 35 can expand and contract in the flexible tube 36 in the axial direction.

The flexible tube 36 of the flexible tube 36
The distal end portion extending to near the connection portion between the and the bending portion 14 is closed by a coil stopper (bottom portion) 37, and the distal end portion of the coil 35 contacts the coil stopper 37. In other words, the flexible tube 36 has a bottomed cylindrical shape whose tip is closed by the coil stopper 37, and the closed tip prevents movement of the coil 35 toward the tip of the insertion portion 11. Regulating.

On the other hand, as shown in FIG. 4, the proximal end of the flexible tube 36 located on the operation section 12 (connecting section 16) side is an opening, and A linear guide member 40 fixed to the tube fixing member 38 described above is provided at the open end. Straight guide member 4
Reference numeral 0 denotes a bottomed cylindrical member that covers the end of the flexible tube 36. A straight guide key (straight guide member) 40a is fixed to the inner peripheral surface of the flexible tube 36 in the axial direction of the coil 35. Is formed with a through hole 40b. A forward / reverse drive motor 44 is also fixed in the operation unit 12 via a motor holding member 46, and a lead screw 45 extending from the forward / reverse drive motor 44 has a through hole formed in the straight guide member 40. It extends to the inside of the straight guide member 40 and the flexible tube 36 through 40b. The lead screw 45 has a threaded portion 45 a formed on the outer peripheral surface of the straight guide member 40 and the portion inserted into the flexible tube 36, and the threaded portion 45 a is formed by a screw hole formed in the coil pressing member 41. 41a is screwed. The coil pressing member 41 has a key groove 41b that engages with the aforementioned linear guide key 40a provided on the linear guide member 40, and moves straight in the axial direction of the coil 35 due to the relationship between the linear guide key 40a and the key groove 41b. Supported movably,
It is in contact with the end of the coil 35. In other words, both ends of the coil 35 are sandwiched between the coil stopper 37 fixed to the distal end side of the flexible tube 36 and the coil pressing member 41 movably provided on the proximal end side.

The lead screw 45 is connected to the forward / reverse drive motor 4
4, the lead screw 4
When 5 rotates, a force is applied to the screw hole 41a of the coil pressing member 41 by the screw portion 45a. Here, the coil pressing member 41 includes a linear guide key 40a and a key groove 41b.
The rotation is restricted by the lead screw 4
5 does not rotate, but advances and retreats in the axial direction of the coil 35 due to the relationship between the screw portion 45a and the screw hole 41a.

The operation unit 12 is provided with a pair of motor operation buttons 47 and 48, and the pair of motor operation buttons 47 and 48 are connected to a motor control circuit 49.
The motor control circuit 49 includes a pair of motor operation buttons 47,
When one of the buttons 48 is pressed, the forward / reverse drive motor 44 is rotated forward, and when the other is pressed, the forward / reverse drive motor 44 is rotated reversely. The forward / reverse drive motor 44 is driven while the motor operation buttons 47 and 48 are being pressed. When the push is released, the forward / reverse drive motor 44 stops.

The manner in which the flexibility of the flexible tube 15 is adjusted in the above-described flexible endoscope will be described. Coil 35
Is in the free state, the coil pressing member 41 located on the opening side of the flexible tube 36
6 is located farthest from a coil stopper 37 provided on the opposite side. The coil 35 has a characteristic that it is difficult to bend (harden) when compressed, and has a characteristic that it is easy to bend (soften) when expanded (when the compression is released). It is the smallest and therefore the flexible tube 15 is the most flexible.

In this state, the motor operation button 47 or 48 is operated to drive the forward / reverse drive motor 44, and the coil pressing member 41 is inserted via the lead screw 45 into the insertion portion 11.
The coil pressing member 41 presses the coil 35 when it is moved in the direction of the front end (to the right in FIG. 4). As described above, since the movement of the distal end of the coil 35 in the distal direction of the insertion portion 11 is regulated by the coil stopper 37, the coil 35 whose base end is pressed is limited in the amount of movement of the coil pressing member 41. A corresponding amount is compressed in the flexible tube 36.
The compressed coil 35 has increased bending rigidity as compared with the free state, and as a result, the flexible tube portion 15 in which the coil 35 is located is hardened.

The degree of compression of the coil 35, that is, the bending rigidity, can be arbitrarily adjusted by operating the motor operation buttons 47 and 48. For example, the motor operation button 47 is an operation button for curing, and the motor operation button 48
Is set as an operation button for softening, and when the flexibility of the flexible tube portion 15 is insufficient with respect to an operator's ideal hardness, the motor operation button 47 for curing is pressed to release the coil 35. What is necessary is just to harden further. Conversely, if the coil 35 is too hard, the motor operation button 48 for softening may be pressed appropriately. Motor operation button 47 or 48
Is released and the forward / reverse drive motor 44 stops, the rotation of the lead screw 45 is restricted, so that the coil pressing member 41 is fixed, and the bending rigidity of the coil 35 is kept constant. Further, when the insertion of the insertion portion 11 into the observation target is completed and the cured state of the flexible tube portion 15 is released,
It is only necessary to keep pressing the motor operation button 48 for softening, move the coil pressing member 41 in the direction away from the coil stopper 37, and return the coil 35 to the free state. When the coil 35 returns to the free state, the motor control circuit 49 stops the forward / reverse drive motor 44 regardless of the pressed state of the motor operation button 48. Such a motor stop control can be performed by a known technique.

As described above, in the endoscope of the present embodiment,
It is possible to change the flexibility of the flexible tube portion 15,
In particular, there are the following advantages. First, as a means for changing the degree of compression of the coil 35, the coil pressing member 41 for sandwiching the coil 35 between the coil stopper 37 and the coil stopper 37 is used, so that a coil pulling wire as shown in FIG. Therefore, there is no possibility that the coil pulling wire will be cut and become inoperable, and there will be no such a problem that the flexibility of the flexible tube portion suddenly changes against the operator's intention.

Since the coil 35 is housed inside the flexible tube 36, the displacement of the coil 35 in the radial direction is prevented by the flexible tube 36. In particular, in the present embodiment, a wire for coil pulling is not inserted into the center of the coil 35, and the coil 35 is not configured to prevent buckling from the inside thereof.
It is effective to store it in the inside 6 to prevent buckling. Further, since the coil 35 is covered with the flexible tube 36, the coil 3
There is no possibility that the coil 5 will bite the other built-in components because the 5 does not directly contact the other built-in components.

As described above, the flexible tube 36 functions to prevent interference of the coil 35 with other built-in endoscopes, and furthermore, the function of regulating the position of the distal end of the coil 35 by the coil stopper 37. It also has. For example, unlike the illustrated embodiment, assuming that the flexible tube 36 does not have a bottom portion such as the coil stopper 37, the distal end position of the coil 35 is not regulated. The whole moves, and the coil 35 cannot be compressed. On the other hand, in the flexible tube 36 having the coil stopper 37 as in the embodiment, when the coil 35 is pressed by the coil pressing member 41, the coil 35 can be reliably compressed.

FIG. 6 shows a different embodiment of the present invention. In this embodiment, the driving means for rotating the lead screw 45 is different from that of the above-described embodiment. Specifically, the lead screw 45 is rotated by the manual operation knob 51 instead of the forward / reverse drive motor. The manual operation knob 51 is an operation member located on the outer surface of the endoscope, and extends the lead screw 45 into the operation section 12 through a through hole formed in the exterior material 52 of the endoscope.
By rotating the manual operation knob 51 in the forward and reverse directions, the lead screw 45 is rotated in the forward and reverse directions. As a result, the coil pressing member 41 moves, and the degree of compression of the coil 35 can be changed. In FIG. 6, the manual operation knob 51 and the lead screw 45 are directly connected, but a gear or the like can be interposed between the two.

[0033]

As is apparent from the above, according to the present invention, in the endoscope in which the flexibility of the flexible tube portion is changed by the change in the bending rigidity of the coil, it is possible to prevent the coil from being operated accidentally. This can prevent a problem such as interference of the coil with the built-in endoscope.

[Brief description of the drawings]

FIG. 1 is an overall view of a flexible endoscope to which the present invention is applied.

FIG. 2 is a side sectional view showing the vicinity of a base end of a coil for adjusting flexibility in the endoscope of FIG. 1;

FIG. 3 is a view showing the vicinity of a tip end of the flexibility adjusting coil shown in FIG. 2;

FIG. 4 shows an embodiment of the entire flexibility adjusting coil shown in FIG. 2 and a mechanism for changing the degree of compression of the coil.
It is sectional drawing seen from the side.

FIG. 5 is a cross-sectional view of the vicinity of the coil pressing member, taken along the line VV in FIG.

6 is a diagram showing an embodiment in which a manual operation knob is provided instead of the forward / reverse drive motor of FIG.

FIG. 7 is a diagram illustrating a coil operating mechanism of a conventional wire pulling type as a comparative example with respect to the embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 electronic endoscope 11 insertion section 12 operation section 13 distal end section 14 bending section 15 flexible tube section 16 connecting section 20A 20B bending operation knob 21A lock knob 21B lock lever 23 universal tube 24 connector section 25 remote operation button switch 26 Button 27 Treatment tool insertion port projection 28 Treatment tool insertion channel 29 Suction tube 30 Suction button 31 Flexible tube 32 Bend-proof rubber tube 35 Coil (coil body) 36 Flexible tube (coil storage tube) 37 Coil stopper (bottom part) 38 Tube fixing member 40 Straight running guide member 40a Straight running guide key (straight running guide member) 40b Through hole 41 Coil pressing member 41a Screw hole 41b Key groove 44 Forward / reverse drive motor 45 Lead screw 45a Screw portion 47 48 Motor operation button 49 Motor control Circuit 51 manually operated knob

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keishi Kunii 2-36-9 Maenocho, Itabashi-ku, Tokyo Asahi Gaku Kogyo Co., Ltd. (72) Inventor Shinji Hayakawa 2-36-9 Maenocho, Itabashi-ku, Tokyo No. Asahi Gaku Kogyo Co., Ltd. F-term (reference) 4C061 FF29 HH60 JJ06

Claims (4)

[Claims] 1. An endoscope having a flexible tube portion having flexibility in an insertion portion, wherein the endoscope is provided in the flexible tube portion, has a linear shape in a free state, and has bending rigidity by expansion and contraction in an axial direction. A tubular coil body to be changed; a bottomed tubular coil housing surrounding the outer surface of the coil body, having a bottom surface portion in contact with one end of the coil body and an opening in which the other end of the coil body is located A tube; a coil pressing member provided at an opening of the coil housing tube, the coil pressing member engaging with the coil body; and moving the coil pressing member in forward and reverse directions in the axial direction of the coil body to obtain a bottom surface of the coil housing tube. A variable pressure endoscope comprising: a pressing member driving mechanism for changing the degree of compression of the coil body sandwiched between the portion and the coil pressing member. 2. The flexible endoscope according to claim 1, wherein the pressing member driving mechanism comprises: a lead screw extending in an axial direction of the coil body and having a screw on an outer surface; Formed,
A screw hole into which the screw of the lead screw is screwed; a linear guide member for guiding the coil pressing member in the axial direction of the coil body; and rotating the lead screw in the forward / reverse direction to guide the coil pressing guided in a straight line. A variable-flexibility endoscope comprising: screw driving means for moving the member in the axial direction of the coil body in accordance with the screw and the screw hole. 3. The flexible endoscope according to claim 2, wherein said screw driving means is a forward / reverse drive motor. 4. The flexible endoscope according to claim 2, wherein said screw driving means is a manually operated knob.