JP2013223735A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope capable of curvature operation of a curved section with a lighter load, according to a mode of the operation without impairing the original function of a curving means.SOLUTION: A curved section of an insertion section is curved by operating operation knobs 13UD and 13LR with hand fingers. When an operation lever 26 or an operation grip 27 is operated, the resistance to the operation of the operation knobs 13UD and 13LR is changed from a minimally loaded actuation state to a locked state. In a normal operation mode, a load set when an endoscope is normally operated on the operation knobs 13UD and 13LR is acted from a load actuation state set by load applying members 36 and 37 to a locked state. In a light operation mode, the operation knobs 13UD and 13LR can be operated in a minimal load state where the loads of the load applying members 36 and 37 do not act.

Description

  The present invention relates to an endoscope used as a colonoscope or the like in which an insertion path of an insertion portion is bent in a complicated manner and a large resistance acts on the insertion portion.

  A colonoscope as a kind of endoscope is inserted through the anus from the anus, but this insertion part leads from the rectum through the sigmoid colon to the descending colon, and further into the transverse colon. It is required to be able to progress through the transverse colon to the ascending colon, more preferably to the cecum. Of the insertion paths, the sigmoid colon has a three-dimensional loop structure, and the transition from the sigmoid colon to the descending colon has an extremely bent structure. Moreover, when the intestinal tract wall is moved while the insertion portion slides, the intestinal tract wall easily expands and contracts according to the movement. From the above, it is difficult to insert the insertion portion into the insertion path, and high skill is required.

  In order to pass through the sigmoid colon, it is necessary to perform a rather complicated operation such as twisting the insertion portion, applying a loop, and reciprocating back and forth. However, the sigmoid colon is a site where the insertion depth of the insertion portion is shallow, and it is possible to exert an operating force on the distal end of the insertion portion. By the way, in the case where the deep part of the large intestine is to be examined, even if it passes through the sigmoid colon, the transition part from the sigmoid colon to the descending colon, the transition part from the descending colon to the transverse colon, If the bent portions that face each other are not passed, the site to be inspected will not be reached.

  The deeper the insertion depth of the insertion portion, the more constricted the anus and the tortuous sigmoid colon passage portion become the obstacle to the transmission of the operation force of the pushing operation, and the operation force from outside the body to the insertion portion. May not reach the tip accurately. In addition, the insertion portion and the intestinal tract wall may be in close contact with each other, making it impossible to advance or retreat. Therefore, the subject is forced to suffer and the operability is also deteriorated. Furthermore, there is a possibility that the directionality of the insertion portion in the insertion direction may be mistaken, and the bent portion may not be smoothly passed.

  From the above, in Patent Document 1, a vibration member is provided inside the connecting portion between the bending portion and the flexible portion of the insertion portion, and this vibration member is operated to vibrate the side surface in the vicinity of the distal end of the insertion portion. By giving, the thing which was made to cancel | release the contact | adherence of an insertion part and an intestinal tract wall, ie, a stick state, is disclosed.

JP 2000-148987 A

  As described above, if the side near the distal end of the insertion portion is vibrated, the insertion portion can be improved in insertion operability even if the insertion portion can be eliminated to some extent from the intestinal wall. is not. For example, in the large intestine, for the operation of passing through an extremely bent portion such as a transition portion from the sigmoid colon to the descending colon and a transition portion from the descending colon to the transverse colon, the distal end portion of the insertion portion vibrates. Even if it is given, the passage cannot be promoted. In addition, it is not only the close contact of the insertion part with the intestinal tract wall that hinders the progress of the insertion part, but also the problem of how to select the route. It may not proceed smoothly. Of course, it is meaningful for the insertion operation to vibrate the insertion portion, but for that purpose, providing a driving means for generating vibration inside the distal end portion of the insertion portion makes the insertion portion unnecessarily thick. However, it is not desirable in that it is complicated and structurally complicated.

  Therefore, in order to improve the insertion operability of the insertion portion, the insertion operability of the insertion portion is improved at a deep part in the body cavity tube that is easily expanded and contracted, especially like the intestinal tract wall, etc. For this reason, a colonoscope insertion method has been proposed that uses the unnamed groove of the large intestine as an index and uses the elasticity of the insertion portion. This is a part of the insertion portion, paying attention to the bending portion that is bent by remote operation from the main body operation portion, and operating the bending operation means to bend the bending portion up and down or left and right. This is a procedure to insert without pushing or twisting.

  By the way, in the insertion part, the base end side is a soft part from the site | part in which the bending part is provided. The original function of the soft portion is to provide flexibility in the bending direction so that the insertion path can be bent when the insertion path is bent. Therefore, when the insertion operation is performed in the body cavity tube that is a passage sufficiently larger than the outer diameter of the insertion portion, the flexible portion forms a flexible deflection in the body cavity tube. In addition, a loop is formed along the insertion path such as the sigmoid colon.

The soft part has a certain degree of elasticity.When the movement of the insertion part in the return direction with respect to the insertion path, that is, the reverse movement is restricted, the bending part is operated repeatedly to swing the soft part. As a result of acting to release the deflection and loop and trying to straighten, the tip portion moves forward. For example, in a colonoscope, the loop part of the anus and sigmoid colon, or the part grasped by the operator in the insertion part becomes a part that regulates the reverse movement of the insertion part, and the bending part is operated to swing and move forward. By doing this, the flexure and loop become straight due to the elasticity of the soft part, and this is converted into a propulsive force, the tip part advances, and the insertion part itself does not have to be pushed or twisted Will be inserted. From the above, by performing this swinging forward operation, even if the insertion resistance with respect to the insertion portion is large and the path is extremely bent, the body cavity can be smoothly and reliably advanced to a desired position. .

  Therefore, in order to give a sufficient forward thrust to the distal end of the insertion portion and insert it deep into the body cavity tube, the bending portion must be repeatedly reciprocated to some extent frequently up and down and left and right.

  The bending operation means for operating the bending portion of the insertion portion is attached to the main body operation portion provided at the proximal end portion of the insertion portion, and is composed of an operation knob, a lever, etc., and is a finger of a hand that holds the main body operation portion. A rotation operation member that is rotated at is provided. Since it can be operated with fingers, it is necessary to lighten the movement of the rotating operation member to reduce the burden on the operator. However, if the movement of the rotating operation member is too light, the operability is rather deteriorated. For example, by bending the bending portion, an operation of slightly shifting the visual field direction left and right or up and down is performed from the state in which the direction that is the endoscope observation means is the observation visual field. At this time, if the movement of the rotating operation member is too light, even if a slight operation force is applied, the bending portion moves greatly, and operation stability cannot be obtained. Therefore, in a normal endoscope, the turning operation member for bending operation is set so as to cause a certain load and resistance to the bending operation particularly during observation. Therefore, it is extremely difficult to frequently and repeatedly operate the bending operation means in which a predetermined load is set in this way, which is a great burden for the operator who operates the endoscope, and the degree of fatigue is large. Become. For this reason, in order to perform an operation of moving the distal end of the insertion portion forward by a bending operation of the bending portion, it is necessary to change the configuration of the bending operation means.

  As described above, the bending operation means generates a load to some extent during the bending operation in consideration of the stability of the operation. However, the bending operation unit must be able to hold the bending portion in a desired bending state. For example, when a region of interest is captured in the field of view by the endoscopic observation means, in order to examine the region of interest and to obtain a tissue sample, even if the bending portion is curved, The distal end portion of the insertion portion is fixedly held by locking in the posture state. For this reason, the bending operation means includes a so-called lock member that applies a load that holds the bending portion in the posture as it is in addition to the rotation operation member. In addition, the lock member not only switches between a state where the bending operation can be performed and a locked state, but also allows the load to be adjusted in order to give a desired operation feeling when performing the bending operation. It is common.

  Therefore, as described above, the bending operation means is subjected to a certain load during the normal operation of the rotation operation member, and the original function of exhibiting the lock mechanism in the bending state of the bending portion is maintained. Must. In addition, it is extremely important for the insertion portion to be inserted into a path that is difficult to insert, so that the insertion portion can be reliably and smoothly propelled within the body cavity tube. The present invention has been made in view of the above points, and it is possible to perform a bending operation of a bending portion with a lighter load according to an operation mode without impairing the original function of the bending operation means. That is the purpose.

  In order to achieve the above-described object, the present invention is provided with an insertion portion connected to the main body operation portion, and the insertion portion is not provided with a hard tip portion, a bending portion, or a soft portion provided with an endoscope observation means from the tip. The body operation unit is provided with a bending operation means having a rotation operation member, and the bending operation means can be operated to bend the bending part, and the bending part is in a predetermined posture. A locked state in which a maximum load to be held in a state is applied, a loaded operating state in which the bending portion can be bent while generating a load on the rotating operation member, and a load lighter than the loaded operating state A load setting means for changing a load at the time of operation on the rotating operation member stepwise or continuously to a minimum load operating state, and the load setting means with respect to the rotating operation member in the locked state From the above load Comprising a normal operating mode for applying a load ranging dynamic state, and a mode switching member for switching between the light operation mode to the minimum load operating state with respect to the rotational operation member. The load setting means varies the load continuously or stepwise between the locked state and the loaded operation state with respect to the rotation operation member, and the minimum load operation state is: The operation force assist mechanism is configured to increase the operation force toward the operation direction of the rotation operation member, and the mode switching unit includes a switching unit that switches the operation force assist mechanism between a non-operation state and an operation state. It is characterized by that.

  In addition, it is preferable that the said operation force assist mechanism is comprised from the artificial muscle provided in the motor provided in the said bending operation means, or the said bending part.

  As described above, since the load for the operation of the rotation operation member constituting the bending operation means can be set to the light operation mode in which the minimum load operation state is smaller than the range set for the normal operation, The operation of the turning operation member of the bending operation means can be remarkably improved when performing an operation of moving forward while swinging the distal end of the insertion portion without impairing the operability of the endoscope. Can be reduced.

1 is an overall configuration diagram of a general endoscope. FIG. It is a structure explanatory view showing the structure of a mechanism that performs a bending operation of an endoscope. It is sectional drawing of the connection part between the soft part of the insertion part which abbreviate | omits a built-in thing and a bending part. It is sectional drawing of the bending operation means of this invention. FIG. 5 is a cross-sectional view of the main part showing the operating state of the load setting means in the bending operation means of FIG. 4. It is sectional drawing which expand | deploys and shows the structure of the click mechanism as an example of a mode switching means. It is principal part sectional drawing of the bending operation means which shows the other example of a mode switching means, Comprising: It is the figure made into the light operation mode. It is sectional drawing similar to FIG. 7 made into normal operation mode. It is composition explanatory drawing which shows the state which has inserted the endoscope of this invention in the large intestine. It is operation | movement explanatory drawing at the time of the swinging forward operation of an endoscope. It is sectional drawing which shows the principal part structure of the bending operation means of this invention. It is a principle figure of the ultrasonic motor used in a bending operation means. It is structure explanatory drawing of an action control mechanism. It is composition explanatory drawing which shows the other example of the operating force assist mechanism. It is sectional drawing which shows the structure of the front-end | tip part of an insertion part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, FIG. 1 shows a schematic configuration of an endoscope. In the figure, 1 is a main body operation unit, 2 is an insertion unit, and 3 is a universal cord. The insertion portion 2 is a flexible portion 2a that bends in an arbitrary direction along the insertion path from the connection side to the main body operation portion 1, and a bending portion 2b is connected to the distal end of the flexible portion 2a. Further, the distal end of the curved portion 2b is a distal hard portion 2c. Endoscope observation means consisting of an illumination part and an observation part is provided on the distal end surface of the distal rigid part 2c, and a treatment instrument is inserted for deriving the treatment instrument and performing operations such as suction of filth in the body. The passage is open. The bending portion 2b is configured such that a bending operation can be performed in order to direct the distal end hard portion 2c in a desired direction. Here, the bending direction of the bending portion 2b is set to four directions, ie, a vertical direction and a horizontal direction. It should be noted that the bending direction can be two directions only in the vertical direction.

  The bending operation of the bending portion 2 b of the insertion portion 2 is performed by a finger of a hand that holds the main body operation portion 1 by remote operation from the main body operation portion 1. For this purpose, the main body operation unit 1 is provided with a bending operation means 10. As conceptually shown in FIG. 2, the bending operation means 10 has a pulley 11, and a pair of operation wires 12 and 12 are wound around the pulley 11, and these operation wires 12 are inserted. It extends to the tip of the curved part 2b of the part 2. Accordingly, when the pulley 11 is turned in the direction of the arrow RU in FIG. 2, the bending portion 2b is bent in the direction of the arrow BU, and when the pulley 11 is turned in the direction of the arrow RD, the bending portion 2b is bent in the direction of the arrow BD. . Two sets of pulleys and a pair of operation wires wound around the pulleys are provided, whereby the bending portion 2b can be bent in four directions, up and down and left and right.

  FIG. 3 shows a cross section of a connecting portion between the flexible portion 2a and the bending portion 2b in the insertion portion 2. As shown in FIG. As is apparent from this figure, the curved portion 2b is constructed by sequentially pivoting the node rings 4, and the front and rear node rings 4, 4 are pivoted alternately left and right and up and down. The distal end of the operation wire 12 is fixed to the state-of-the-art node ring 4, and is sequentially inserted into the pivot pin 5 and drawn into the soft portion 2a. In the soft portion 2a, a flexible sleeve made of a contact coil is provided. 6 is inserted. And the front-end | tip of the flexible sleeve 6 is fixed to the connection part of the soft part 2a and the curved part 2b with the connection pipe 7, and a base end part is also fixed in the main body operation part 1 using the same connection pipe. .

  In the main body operation unit 1, the operation wires 12 led out from the four flexible sleeves 6 are wound up around one pulley 11 UD, and the operation wires 12 and 12 for up and down operation are operated. The wires 12 and 12 are wound around the other pulley 11LR. For this purpose, the main body operation unit 1 is provided with the operation knob 13UD and the operation knob 13LR shown in FIG. 1, and these operation knobs 13UD and 13LR constitute the turning operation means of the bending operation means 10. FIG. 4 shows a cross section of the bending operation means 10.

  In the figure, reference numeral 20 denotes a support plate provided inside the main body operation unit 1, and a fixed shaft 21 is erected on the support plate 20. A double hollow shaft of an inner shaft 22 and an outer shaft 23 is fitted to the fixed shaft 21 so as to be slidable coaxially. A pulley is connected to each of the inner shaft 22 and the outer shaft 23. Has been. Connected to the outer shaft 23 is a pulley 11UD for bending operation in the vertical direction, and connected to the inner shaft 22 is a pulley 11LR for bending operation in the left-right direction. A connecting drum 24 is fitted and fixed to the outer shaft 23, and an operation knob 13UD is attached to the connecting drum 24. The inner shaft 22 protrudes from the outer shaft 23, and the connecting drum 25 is fitted and fixed to the protruding portion, and the operation knob 13 LR is attached to the connecting drum 25.

  Therefore, when the operation knob 13UD is rotated, the operation force is transmitted to the pulley 11UD via the outer shaft 23, and the pulley 11UD rotates according to the operation amount, and the operation wires 12 and 12 are pushed and pulled. Thus, the bending portion 2b is bent in the vertical direction. On the other hand, when the operation knob 13LR is rotated, this operating force is transmitted to the pulley 11LR via the inner shaft 22, and the bending portion 2b is bent left and right.

  Here, the operation knobs 13UD and 13LR are operated by fingers, and are configured to include a load setting means in order to vary the resistance generated during the operation, that is, the load on the operation. As the load setting means, an operation lever 26 is provided for setting a load during a bending operation in the up / down direction, and an operation knob 27 is provided for setting a load during the bending operation in the left / right direction. It has been.

  By operating the operation lever 26 or the operation knob 27, the resistance to the rotation operation of the operation knobs 13UD and 13LR can be continuously changed from the minimum load operating state to the locked state. First, in the locked state, when the bending portion 2b is bent and is bent at a desired angle, a slight load is applied in a direction in which the bending portion 2b is further bent or a direction in which the bending is eliminated. However, the operation knobs 13UD and 13LR are locked so as to generate a load sufficient to stably maintain the posture state.

  Friction plates 28 and 29 are provided for locking. The friction plates 28 and 29 are disposed between the receiving members 30 and 31 and the pressing members 32 and 33, and the pressing members 32 and 33 are connected to the operation lever 26 and the operation knob 27 and are provided with a screw ring 34. , 35. When the operation lever 26 and the operation knob 27 are rotated, the pressing members 32 and 33 are displaced in the axial direction of the inner shaft 22 and the outer shaft 23. When the pressing members 32, 33 move in the direction approaching the receiving members 30, 31, the friction plates 28, 29 are sandwiched and pressed between the pressing members 32, 33 and the receiving members 30, 31. Note that the operation lever 26 is screwed with a pulley housing 20a erected on the support plate 20. Therefore, when the operation lever 26 is rotated, the operation lever 26 moves up and down. On the other hand, when the operation knob 27 is rotated, the pressing member 33 is rotated via the pin 27 a and the pressing member is moved up and down along the screw ring 35.

  When the pressing members 32 and 33 are separated from the receiving members 30 and 31 from the locked state, the pressure contact force with respect to the friction plates 28 and 29 is relieved, the sliding resistance therebetween decreases, and the operation knobs 13UD, The load for the rotation operation of 13LR is reduced. When the operation lever 26 and the operation knob 27 are further rotated, the pressing members 32 and 33 are completely separated from the friction plates 28 and 29 to be in a free state, and the operation lever 26 and the operation knob 27 by the friction plates 28 and 29 are set. The load on will not work.

  Load applying members 36 and 37 made of, for example, an annular rubber member are fixedly provided on the pressing members 32 and 33 on the outer peripheral side from the positions where the friction plates 28 and 29 are disposed. Even when 29 is in a free state, the load applying members 36 and 37 are in contact with the receiving members 30 and 31. This state is a loaded operation state, and in this state, the operation lever 26 and the operation knob 27 are operated under the load action of the load applying members 36 and 37. Accordingly, by setting the size and elastic force of the load applying members 36 and 37 and the sliding resistance with the receiving members 30 and 31 as appropriate, the value of the smallest load is set in the loaded operation state. .

  From the above state, when the operation lever 26 and the operation knob 27 constituting the load setting means are further rotated, the load applying members 36 and 37 are also separated from the receiving members 30 and 31. This is the minimum load operating state. That is, it is a state in which the action of the load by the load setting means is completely released. In this minimum load operating state, the operation knobs 13UD and 13LR can be operated with the lightest operating force. That is, the resistance when the operation wire 12 is pushed and pulled, for example, the resistance against the rotation of the pivot pin 5 in the bending portion 2b, and the sliding resistance of the operation wire 12 in the flexible sleeve 6 are constant. In this state, the minimum resistance when operating the operation knobs 13UD and 13LR, that is, the sliding resistance when transmitting the driving force from the operation knobs 13UD and 13LR to the pulleys 11UD and LR is minimized.

  The above operation between the operation knob 13UD side and the operation lever 26 as its load setting means is shown in FIG. FIG. 5A shows a locked state in which the friction plate 28 is sandwiched and pressed between the receiving member 30 and the pressing member 32 and the maximum load is applied. In this locked state, the bending portion 2b is held in a predetermined posture, and the operation knob 13UD is substantially inoperable.

  In FIG. 5B, the friction plate 28 is in a free state between the receiving member 30 and the pressing member 32, and no friction acts between them. However, since the load applying member 36 provided on the pressing member 32 is in contact with the receiving member 30, a loaded operation state in which a predetermined load is applied due to the friction of this portion is obtained. In this loaded operation state, a predetermined load is set for the turning operation of the operation knob 13UD. That is, when the operation knob 13UD is operated, the bending portion 2b is stably bent and an operation force necessary for enabling a fine operation is given. Therefore, when inserting the insertion portion 2 and observing in the body cavity, the distal end hard portion 2c can be stably held, and when the bending operation is performed, the operator is not greatly burdened.

  In a loaded operation state, it is desirable that the load acting on the operation knobs 13UD and 13LR is variable. For example, when the inner wall of the body cavity is inspected by the endoscope observation means at a certain position in the body cavity, for example, when the observation is performed by slightly shifting the visual field of the endoscope observation means, the operation knob 13UD is used. , 13LR is preferably given a larger operation load. In this case, a desired operation load is applied to the operation knobs 13UD and 13LR by operating the operation lever 26 and the operation knob 27 constituting the load setting means in the locking direction.

  And the minimum load operation state is shown by FIG.5 (c). In this minimum load operating state, no resistance is generated between the pressing members 32, 33 and the receiving members 30, 31, so that the operation lever 26 and the operation knob 27 can be operated with a lighter load than in the loaded operation state. Become. In this minimum load operating state, unlike the loaded operating state, the bending portion 2b cannot be finely controlled, but the operating lever 26 and the operating knob 27 can be operated with the lightest operating force and can be easily bent. it can.

  In the above description, the operation mode of the operation knobs 13UD and 13LR set when the endoscope is normally operated, that is, the normal operation mode, is from the loaded operation state to the locked state. On the other hand, the operation knobs 13UD and 13LR are in the light operation mode in the minimum load state, and the normal operation mode and the light operation mode can be switched by the mode switching means. This mode switching means comprises a click ball 40, a click recess 41 and a relief groove 42, and a wall 43 therebetween.

  FIG. 6 shows an expanded mode switching means on the operation knob 13UD side. As is apparent from this figure, the click ball 40 is provided on an attachment member 44 for attaching the bending operation means 10 to the main body operation portion 1, and the click recess 41, the escape groove 42 and the wall portion 43 are provided on the operation lever 26. Is formed. When the operation lever 26 is disposed at a position where the light operation mode is set, the click ball 40 is engaged with the click recess 41. Then, when the operation lever 26 is rotated from this position and displaced to the position where the normal operation mode is set, the click ball 40 rides on the wall portion 43, and when the wall portion 43 is exceeded, the click ball 40 moves to the escape groove. 42, the click ball 40 is brought into a non-contact state with the operation lever 26, and the operation lever 26 is displaced from a state where an arbitrary load is applied to a locked state in a loaded operation state. Thus, since the wall portion 43 with which the click ball 40 abuts is present at the stroke end position in the loaded operation state, the operator who operates the operation lever 26 is at the stroke end position in the normal operation mode. I can recognize that.

  Further, as the mode switching means on the operation knob 13UD side, as shown in FIGS. 7 and 8, the operation lever 126 is configured to be movable up and down along the fitting portion to the connection drum 124. The elastic holding member 140 may be mounted on the outer peripheral surface of 124. As shown in FIG. 7, when the operation lever 126 is in the lowered state, the load applying member 36 is separated from the receiving member 30 to be in the minimum load operating state, and the light operation mode is set. At this time, the elastic holding member 140 protrudes outwardly at a position above the tip of the screw ring 134 that is connected to the operation lever 126. When the operation lever 126 is in the lowered position, the operation lever 126 is in a free fitting state with respect to the pulley housing 20a. On the other hand, as shown in FIG. 8, when the operation lever 126 is lifted, the screw ring 134 provided integrally with the operation lever 126 rides on the elastic holding member 140 and the elastic holding member 140 is compressed and screwed. Ring 134 is held in that position. As a result, the load applying member 36 comes into a loaded operation state in which the load applying member 36 comes into contact with the receiving member 30, and is configured to switch to the normal operation mode. In the normal operation mode, when the operation lever 26 is turned, the pressing member 32 moves up and down. As a result, the operation knob 13UD can be changed from the loaded operation state to the locked state. On the other hand, as the mode switching means on the operation knob 13LR side, the operation knob 27 can be moved up and down together with the pressing member 33. When the operation knob 27 is raised, the light operation mode is set, and when the operation knob 27 is lowered, the mode is switched to the normal operation mode. It can be constituted as follows.

  The endoscope having the above-described configuration is used as a so-called colonoscope when the insertion portion 2 is inserted into the large intestine. That is, as shown in FIG. 9, the insertion section 2 is inserted from the anus 50, reaches the descending colon 53 through the rectum 51 through the sigmoid colon 52, and is further guided into the transverse colon 54. It is possible to proceed to 54 through the ascending colon 55, more preferably to the connection between the cecum 56 and the ileum 57.

  The sigmoid colon 52 has a three-dimensional loop structure and is difficult to insert. However, since the insertion position is shallow, the distal end of the insertion portion 2 can be controlled. Therefore, the insertion part 2 can be advanced along the insertion path. When the distal end hard portion 2 c of the insertion portion 2 passes through the sigmoid colon 52, it enters the descending colon 53 and then heads toward the transverse colon 54. Here, since the insertion portion 2 passes through the narrowed portion called the anus 50 and is bent in a complicated manner in the sigmoid colon 52, the insertion portion 2 can be inserted even if it is operated to push the proximal end portion of the insertion portion 2. The pushing force may not be sufficiently transmitted to the tip portion reaching the deep part of the path. In addition, a large resistance is generated against the pushing of the insertion portion 2, and the soft portion 2a of the insertion portion 2 is flexible in the bending direction, so that the inserted insertion portion 2 is bent. It will be. As a result, as shown by the solid line in FIG. 10, the pushed length is absorbed halfway, and the tip portion does not advance any further. In particular, the transition part from the descending colon 53 to the transverse colon 54 (splenic curvature) and the transition part from the transverse colon 54 to the ascending colon 55 (liver curvature) are extremely curved, and it is extremely difficult to pass these parts. It is.

  In this manner, the length of the deflection in the inserted insertion portion 2 and the flexible flexible portion 2a is accumulated at a position in front of the sigmoid colon 52, and a loop is formed along the insertion portion path. Is done. Further, the insertion portion 2 is restricted to move in the direction opposite to the insertion direction, that is, the reverse movement, at the anus 50 and the sigmoid colon 52.

  Under the above circumstances, the bending portion 2b positioned near the distal end of the insertion portion 2 is rapidly and repeatedly bent up and down, preferably up and down and left and right, for example, so as to be perpendicular to the anonymous groove of the large intestine. By operating, the tip of the insertion portion 2 is swung. As a result, as shown by the phantom line in FIG. 10, the distal end hard portion 2c moves forward by the action of the elastic force of the insertion portion 2, and the deflection and the loop are substantially eliminated. At this time, the surgeon grasps the proximal end portion of the insertion portion 2, but does not need to operate it in the direction of pushing it. Therefore, the insertion part 2 in the deep part of the large intestine advances more smoothly and reliably by repeating the pushing of the insertion part 2 and the subsequent swinging motion of the bending part 2b. In addition, since the head moves forward while searching for the path to be inserted, the flexion that is the transition from the descending colon 53 to the transverse colon 54 or the transition from the transverse colon 54 to the ascending colon 55 It will pass smoothly through the part.

  As described above, the operation knobs 13UD and 13LR are operated in order to move forward while swinging the distal end of the insertion portion 2. At the time of this operation, the direction of the hard tip portion 2c is not controlled, but the bending portion 2b is reciprocally bent. Therefore, it is desirable that the operation can be performed with the lightest possible operating force. Therefore, the operation lever 26 and the operation knob 27 constituting the load setting means are operated to select the light operation mode. At this time, the click ball 40 is engaged with the click recess 41 and is held in that position. As a result, the pressing members 32 and 33 are separated from the receiving members 30 and 31, and the friction plates 28 and 29 and the load applying members 36 and 37 are not in the state shown in FIG. 5C. In addition, the operation knob 13LR also acts only with a very light load, the operability thereof is improved, and the burden on the operator who operates the endoscope is reduced.

  Then, when the distal end hard portion 2c of the insertion portion 2 is inserted to a predetermined depth position in the large intestine, the insertion portion 2 is pulled back from that position, and during this time, observation in the large intestine is performed by the endoscope observation means. I do. At this time, the operation lever 26 and the operation knob 27 are operated so that the click ball 40 gets over the wall 43 from the click recess 41 and is positioned in the escape groove 42. As a result, the operation mode is switched to the normal operation mode, and in this operation mode, the state shown in FIG. Accordingly, since resistance to the operation of the operation knobs 13UD and 13LR is generated, a slight operation force is required. However, the bending portion 2b can be finely controlled, and the direction of the distal hard portion 2c is changed when observing the inner wall of the body cavity. It can be reliably controlled. Further, when it is desired to fix the position of the distal end hard portion 2c during this period, the operation lever 26 and the operation knob 27 are appropriately operated so that the operation knobs 13UD and 13LR are locked as shown in FIG. it can.

  As described above, in the normal operation mode, the operation for observing the inside of the body cavity by the endoscope observation means can be performed reliably. In the light operation mode, the distal end portion of the insertion portion 2 is swung. Thus, the operation of inserting along the insertion path can be performed smoothly and easily, and the burden on the operator who performs the operation can be reduced.

  As shown in FIGS. 11 to 13, the endoscope of the present invention includes an operation force assist mechanism. As shown in FIG. 11, the operation force assist mechanism assists the bending portion 2b to promote bending in the operation direction when the operation knobs 13UD and 13LR are operated. For this purpose, ultrasonic motors 60UD and 60LR (hereinafter, when the ultrasonic motor is generically referred to, reference numeral 60 is used) are used. These ultrasonic motors 60UD and 60LR are attached to pulleys 11UD and 11LR.

  As shown in FIG. 12, the ultrasonic motor 60 is a traveling wave type ultrasonic motor in which a stator 62 is attached to a piezoelectric vibrator 61 and a slider 63 is pressed against the stator 62. The piezoelectric vibrator 61 is polarized in plural, and when an AC voltage is applied thereto, the piezoelectric vibrator 61 expands and contracts for each section, and as a result, an elastic bending wave is generated. As a result, the slider 63 moves due to the frictional force generated between the stator 62 and the slider 63. Then, the slider 63 moves in the right direction or the left direction in FIG.

  Therefore, the slider 11 of the ultrasonic motor 60UD is connected to the pulley 11UD, and the slider 63 of the ultrasonic motor 60LR is connected to the pulley 11LR. Further, potentiometers 71UD and 71LR are mounted between the pulleys 11UD and 11LR and the partition wall 70 provided therebetween, and whether or not the pulleys 11UD and 11LR are operated by the potentiometers 71UD and 71LR and either of the left and right sides. A detection is made as to whether or not it has been operated in the direction. Therefore, as shown in FIG. 13, the signals from the potentiometers 71UD and 71LR are taken into the controller 72, and the ultrasonic motors 60UD and 60LR are driven based on the signals from the controller 72.

  By the way, the ultrasonic motors 60UD and 60LR do not directly apply the rotational force to the pulleys 11UD and 11LR, but the pulleys 11UD and 11LR are rotated only by the operation of the operation knobs 13UD and 13LR. As described above, a predetermined load is applied to the operation knobs 13UD and 13LR so that the bending portion 2b can be finely controlled. Thereby, resistance to the operation of the operation knobs 13UD and 13LR is generated.

  However, when performing an operation of moving forward while swinging the distal end of the insertion portion 2, such a load resistance is not necessary, but rather it can be operated more lightly in order to improve operability. Therefore, the ultrasonic motors 60UD and 60LR that assist the operating force are not for rotationally driving the pulleys 11UD and 11LR, but for urging them in the rotational direction. Therefore, the frictional force between the stator 62 and the slider 63 is minimized. As a result, when the operation knobs 13UD and 13LR are manually operated to bend the bending portion 2b in the intended direction, loads of the ultrasonic motors 60UD and 60LR acting on the pulleys 11UD and 11LR are applied to the operation knobs 13UD and 13LR. It is possible to minimize the action. When a clutch is provided between the pulleys 11UD, 11LR and the slider 63 of the ultrasonic motors 60UD, 60LR and operated in the light operation mode, the clutch is turned on so that the light operation is not activated. When operating in the normal operation mode, the clutch may be turned off.

  Accordingly, when the operation knobs 13UD and 13LR are operated, the operation knobs 13UD and 13LR are operated without using the light motor operation mode that requires the assistance of the ultrasonic motors 60UD and 60LR or without the assistance of the ultrasonic motors 60UD and 60LR. In order to switch the normal operation mode to be performed, a changeover switch 73 is provided at an appropriate position of the main body operation unit 1, and this changeover switch 73 constitutes a mode changeover means.

  Also with the above configuration, when the normal operation mode is selected with the changeover switch 73, the bending operation of the bending portion 2b in the insertion portion 2 can be performed finely and reliably, and light operation can be performed. When the mode is selected, when the operation knobs 13UD and 13LR are operated to cause the distal end portion of the insertion portion 2 to swing forward, the bending operation of the bending portion 2b is performed by operating the operation knobs 13UD and 13LR with a light operation force. Is done.

  For example, as shown in FIG. 14, the operation force assist mechanism using the ultrasonic motor has a guide member 80 that guides the operation wire 12 wound around the pulleys 11UD and 11LR in the main body operation unit 1 in the piezoelectric vibrator 161. The stator 162 is attached, and the slider 82 is connected to the operation wire 12 so as to be disposed between the stators 162 and 162 on both sides. Therefore, ultrasonic motors 81 a and 81 b are constituted by the piezoelectric vibrator 161 and the stator 162 and the slider 82 connected to the operation wire 12. When the pulley 11UD or 11LR is rotated in the direction of the arrow in the drawing, the slider 82 provided on the operation wire 12 drawn into the pulleys 11UD, 11LR is directed in the direction of the arrow R, and the other operation wire. If the urging force is applied to the slider 82 connected to 12 in the direction of the arrow F (the operation force is increased), the operation force assist can be performed as described above.

  Furthermore, as shown in FIG. 15, instead of increasing or decreasing the load on the operation knobs 13UD and 13LR, an assist mechanism may be provided on the bending portion 2b. That is, the bending portion 2b of the insertion portion 2 is provided so as to span the artificial muscle 90 between the node rings 4 and 4 at both ends thereof. Although only one place of the artificial muscle 90 is shown in the figure, four artificial muscles 90 are provided at substantially the same position as the four operation wires 12 provided. As described above, when operating the operation knobs 13UD and 13LR, the artificial muscle 90 is controlled to operate in the direction in which the bending portion 2b is bent by driving the artificial muscle 90 when operating in the light operation mode. You can also. That is, when the bending portion 2b is bent, the artificial muscle 90 along the inner side of the curvature is contracted and the artificial muscle 90 along the outer side is extended. Thereby, the artificial muscle 90 can be assisted during the bending operation of the bending portion 2b. Then, whether or not to perform the operation force assist and which artificial muscle 90 to expand and contract when performing the operation force assist depends on the same configuration as the detection and control mechanism shown in FIG. Can do. Here, the artificial muscle includes a piezoelectric type, a shape memory alloy, an electrostatic type, a pneumatic type, etc., but the use of a polymer gel that expands and contracts when a voltage is applied reduces the size and size. It is desirable in terms of controllability.

DESCRIPTION OF SYMBOLS 1 Main body operation part 2 Insertion part 2a Soft part 2b Bending part 2c Hard tip part 10 Bending operation means 11UD, 11LR Pulley 12 Operation wire 13UD, 13LR Operation knob 22 Inner shaft 23 Outer shaft 26, 126 Operation lever 27 Operation knob 28, 29 Friction plates 30, 31 Receiving member 32, 33 Pressing member 36, 37 Load applying member 40 Click ball 41 Click recess 42 Relief groove 43 Wall portion 60, 60UD, 60LR, 81a, 81b Ultrasonic motor 71UD, 71LR Potentiometer 73 Changeover switch 82 Slider 90 Artificial muscle 140 Elastic ring

Claims (2)

An insertion portion is connected to the main body operation portion, and this insertion portion is formed as a hard tip portion, a bending portion and a soft portion provided with endoscope observation means from the tip, and the main body operation portion has a rotation operation member. In an endoscope provided with a bending operation means and configured to bend the bending portion with the bending operation means,
A locked state in which a maximum load is applied to hold the bending portion in a predetermined posture state, a loaded operation state in which an operation to bend the bending portion while generating a load on the rotating operation member, Load setting means for changing a load at the time of operation on the rotation operation member stepwise or continuously to a minimum load operation state that is lighter than a load operation state;
A normal operation mode in which the load setting means applies a load in a range from the locked state to the loaded operation state on the rotation operation member; and the minimum load operation state on the rotation operation member; Mode switching means for switching between the light operation mode and
The load setting means varies the load continuously or stepwise between the locked state and the loaded operating state with respect to the rotating operation member, and the minimum load operating state is the rotation The operation force assist mechanism for increasing the operation force toward the operation direction of the moving operation member is configured, and the mode switching means is configured by a switching means for switching the operation force assist mechanism between a non-operation state and an operation state. Endoscope characterized by.   The endoscope according to claim 1, wherein the operation force assist mechanism includes a motor provided in the bending operation means or an artificial muscle provided in the bending portion.

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