JP4426821B2 - Ultrasound endoscope - Google Patents

Description

  The present invention relates to a driving motor having a motor shaft, a rotating body having a rotating shaft, a driving force transmission mechanism including a shaft coupling that connects the rotating shaft of the rotating body and the motor shaft of the driving motor, and the driving force. The present invention relates to an ultrasonic endoscope including a transmission mechanism.

  Conventionally, an ultrasonic pulse is repeatedly transmitted from an ultrasonic transducer into a living tissue, and an echo signal of the ultrasonic pulse reflected from the living tissue is received by an ultrasonic transducer provided on the same or different body. Various ultrasonic diagnostic apparatuses have been proposed in which an ultrasonic tomographic image, which is a two-dimensional visible image, is displayed on a screen of a display apparatus and used for diagnosis of a lesioned part.

  Examples of equipment used in combination with this ultrasonic diagnostic apparatus include an ultrasonic endoscope and an ultrasonic probe. In the case of the ultrasonic endoscope, an endoscope observation unit for obtaining an endoscopic image of the internal organ and the like, and an ultrasonic tomographic image of the internal organ and the like are provided at the distal end portion of the insertion portion inserted into the body cavity. And an ultrasonic observation unit for obtaining. As one of the ultrasonic endoscopes, there is a mechanical ultrasonic endoscope in which, for example, radial scanning is performed by mechanically rotating an ultrasonic transducer constituting the ultrasonic observation unit. In this mechanical ultrasonic endoscope, a rotational driving force of a driving motor provided in an operation unit or an ultrasonic observation apparatus is transmitted through a flexible shaft to rotate the ultrasonic vibrator.

  For example, in an ultrasonic endoscope in which a drive motor is disposed in a scope connector, the rotational driving force of this drive motor is transmitted to an ultrasonic transducer via a flexible shaft. Therefore, in the ultrasonic endoscope having this configuration, the long flexible shaft is inserted into the endoscope insertion portion, the operation portion, and the universal cord, and therefore, between the rotation of the ultrasonic transducer and the rotation of the drive motor. It is difficult to synchronize. For this reason, there arises a problem that the image quality deteriorates due to shaking or distortion in the ultrasonic tomographic image. In addition, when various external forces are applied to the flexible shaft that transmits the driving force of the driving motor, for example, if a large phase shift occurs between the rotation of the driving motor and the rotation of the ultrasonic transducer, ultrasonic observation becomes impossible. There is a risk of becoming.

  Moreover, there is an ultrasonic endoscope provided in the operation unit instead of disposing the drive motor in the scope connector. In this ultrasonic endoscope, the length of the flexible shaft can be shortened by the amount corresponding to the universal cord to solve some of the problems described above. However, the provision of the drive motor in the operation unit increases the weight of the operation unit, which causes a new problem that the burden on the operator who always holds the operation unit during the examination increases.

  In order to solve these problems, for example, Japanese Patent Application Laid-Open No. 2001-128981 discloses a drive motor, a slip ring, and an encoder that rotate an ultrasonic transducer inside a tip body constituting an insertion portion of an ultrasonic endoscope. And an ultrasonic diagnostic apparatus in which an ultrasonic transducer is directly rotated by the drive motor. In this ultrasonic diagnostic apparatus, a tip cap, an ultrasonic transducer, a slip ring, an encoder, a drive motor, and the like are integrated by a housing which is a casing to constitute an ultrasonic scanning unit.

  Moreover, when cholesterol adhering to the blood vessel is calcified, a rotablator is used as a medical device that scrapes off the calcified portion. For example, Japanese Patent Publication No. 2002-538927 discloses a drive shaft that drives a friction wheel A with a drive motor, transmits this rotation to a friction wheel B connected to the friction wheel A, and is connected to the friction wheel B. An atherectomy power control system for an atherectomy device is shown in which the stripping bar is turned into small particles by rotating the peeling bar at high speed.

Also in this medical device, since the driving force is transmitted to the peeling bar via the drive shaft, there is a possibility that rotation unevenness may occur when an external force is applied to the drive shaft.
JP 2001-128981 A JP 2002-538927 A

  However, in the ultrasonic endoscope disclosed in Japanese Patent Application Laid-Open No. 2001-128981, a mechanism for transmitting the driving force of the drive motor constituting the ultrasonic scanning unit to the vibrator holding unit in which the ultrasonic vibrator is disposed. Is not disclosed. Specifically, a configuration for transmitting the rotational driving force of the motor shaft of the drive motor to the vibrator shaft of the vibrator holding portion is not shown. For this reason, for example, as in the case where the drive motor is disposed in the scope connector or the operation unit, the motor shaft is provided by a shaft coupling provided with a misalignment absorbing mechanism that absorbs eccentricity between the motor shaft of the drive motor and the flexible shaft. When the connection is made with the vibrator shaft, there is a problem that the tip becomes thicker or the hard length becomes longer due to the provision of the misalignment absorbing mechanism.

  On the other hand, when the drive motor is fastened and fixed to the housing constituting the ultrasonic scanning unit, the drive motor may be attached in an inclined state by the fastening force. Then, when the drive motor is mounted in an inclined state, the motor shaft and the vibrator shaft of the vibrator holding part are in an eccentric state, causing uneven rotation, and the drive force of the drive motor is efficient. Failure to transmit to the vibrator shaft causes a problem such as a load on the drive motor.

  Moreover, in the atherectomy device shown in the Japanese translations of PCT publication No. 2002-538927 gazette, it has the structure which connects the motor shaft of a drive motor, and the treatment part shaft of a rotation treatment part with the shaft coupling provided with the misalignment absorption mechanism. As a result, the insertion portion becomes thick and insertion into the blood vessel becomes difficult. Therefore, a driving force transmission mechanism that efficiently transmits the driving force of the driving motor to the treatment portion shaft has been desired.

The present invention has been made in view of the above-described circumstances, and this motor has a simple structure and does not cause problems such as an increase in the diameter of the tip portion and an increase in the hard length. An object of the present invention is to provide an ultrasonic endoscope that can efficiently transmit the rotation of the shaft to the transducer shaft and rotate the ultrasonic transducer in an ideal rotation state. Further, this ultrasonic endoscope, provides the arrangement is always stable rotated in a state that obtained good ultrasonic tomographic image ultrasonic endoscope a vibrator holding portions of the ultrasonic vibrator It is aimed at that.

The ultrasonic endoscope according to the present invention includes a hard tip portion constituting an insertion portion having a vibrator unit arrangement hole, and at least a vibrator shaft arranged in the vibrator unit arrangement hole of the hard tip portion. An ultrasonic vibrator disposed on the vibrator holding member, a drive motor for rotating the ultrasonic vibrator, and a rotational force of the motor shaft by connecting the rotary shaft of the drive motor and the vibrator shaft An ultrasonic endoscope comprising a vibrator unit configured by disposing a shaft coupling in the unit housing to transmit the vibration to the vibrator shaft,
In the configuration in which a gap is provided between the outer peripheral surface of the drive motor and the inner peripheral surface of the unit housing,
The drive motor is provided in the gap, is integrally fixed to the outer peripheral surface of the drive motor, and the drive motor is decentered with respect to a central axis in the unit housing in the unit housing. Motor holding means for holding;
Motor rotation locking means for preventing the drive motor integrally fixed with the motor holding means from rotating within the unit housing when the drive motor is in a driving state;
The gap is an amount capable of absorbing the eccentricity between the motor shaft of the drive motor and the shaft of the vibrator shaft when the motor shaft of the drive motor connected to the vibrator shaft rotates. To do.

Further, the motor holding means is disposed in an elastically deformable elastic sheet-like member that is disposed on the outer periphery of the drive motor, and is disposed inside the unit housing and presses the elastic sheet-like member with a predetermined pressure. has a fixing member, a deformation amount of the elastic sheet is an amount to absorb the eccentricity of the motor shaft of the shaft and the driving motor of the vibrator shaft.

  According to this configuration, when the drive motor to which the motor holding unit is integrally fixed is in the drive state, the drive motor is arranged at a predetermined position without rotating in the unit housing.

  Further, when the drive motor with the motor holding means fixed integrally is in a stopped state, even if the shaft center of the vibrator shaft connected by the shaft coupling and the shaft center of the motor shaft are decentered, When the drive motor is in a rotating state, the eccentricity is absorbed by the gap amount of the gap provided between the drive motor and the unit housing, so that the axis center of the vibrator shaft and the axis center of the motor shaft coincide with each other. Thus, the ultrasonic vibrator rotation unevenness disposed on the vibrator holding member having the vibrator shaft and the load on the drive motor are prevented.

According to the present invention, or thickness diameter of the distal end portion, without increasing the hard length, a simple structure, the drive motor rotation state, and efficiently transmits the rotation of the motor shaft to the transducer shaft, ultra It is possible to provide an ultrasonic endoscope in which a sound wave vibrator can be rotated in an ideal rotation state.

Further, according to the present invention, with this ultrasonic endoscope , the ultrasonic holding unit in which the ultrasonic transducer is disposed can be rotated in a stable state at all times to obtain a good ultrasonic tomographic image. An endoscope can be provided.

  The present invention will be described below with reference to the illustrated embodiments.

  1 to 9 relate to an embodiment of the present invention, FIG. 1 is a diagram for explaining the configuration of an ultrasonic diagnostic apparatus including the ultrasonic endoscope of the present embodiment, and FIG. FIG. 3 is a diagram for explaining the configuration of the distal end portion of the ultrasonic endoscope, FIG. 4 is a diagram for explaining the configuration of a vibrator unit having a driving force transmission mechanism, and FIG. FIG. 6 is a diagram for explaining another mounting structure of the motor shaft and the narrow-diameter portion, FIG. 7 is a diagram for explaining a cross-sectional shape of each step line in FIG. 3, and FIG. 8 is a motor portion. FIG. 9 is a diagram for explaining the structure of the rotation treatment unit provided with a driving force transmission mechanism.

  4A is a top view of the vibrator unit, FIG. 4B is a side view of the vibrator unit, FIG. 4C is a bottom view of the vibrator unit, and FIG. 5A is a sliding resistance. FIG. 5B is a diagram illustrating another configuration of the sliding bearing that reduces sliding resistance, and FIG. 5C is another diagram of the sliding bearing that reduces sliding resistance. FIG. 6A is a view for explaining the configuration, FIG. 6A is a view for explaining an example of attachment of the motor shaft and the small diameter portion, FIG. 6B is a cross-sectional view taken along the line EE of FIG. FIG. 7A is a cross-sectional view taken along line AA in FIG. 3, FIG. 7B is a cross-sectional view taken along line BB in FIG. 7 (c) is a cross-sectional view taken along the line CC of FIG. 3, FIG. 7 (d) is a cross-sectional view taken along the line DD of FIG. 3, and FIG. 8 (a) is a diagram illustrating an example of mounting the motor unit to the unit housing. FIG. 8 (b) is the same as FIG. ) Of FIG. 8C is a sectional view taken along line FF, FIG. 8C is a diagram for explaining another example of attaching the motor unit to the unit housing, and FIG. 8D is a sectional view taken along line GG of FIG. is there.

  As shown in FIG. 1, an ultrasonic endoscope 1 according to this embodiment includes an elongated insertion portion 2 that is inserted into a body cavity or the like, and an operation portion that is provided at a proximal end portion of the insertion portion 2 and also serves as a gripping portion. 3 and a universal cord 4 having flexibility extending from, for example, a base end side portion of the operation portion 3.

  A scope connector 5 is provided at the end of the universal cord 4. The scope connector 5 is provided with a light source connector 6, an electrical connector 7, an ultrasonic connector 8, a suction base 9 and an air / water supply base 10.

  A light source device 11 for supplying illumination light is detachably connected to the light source connector 6. A video processor 12 for performing various signal processing and the like is detachably connected to the electrical connector 7 via a predetermined signal cable (not shown). An ultrasonic observation device 14 is detachably connected to the ultrasonic connector 8 via an ultrasonic cable 13. A suction pump 15 (not shown) is detachably connected to the suction base 9. The air / water supply base 10 is connected to an air / water supply tube (not shown). Thus, the water supply tank 16 is detachably connected.

  The air / water supply cap 10 is formed of a thin member. For this reason, there is a risk of damage due to an unintended impact or the like when a predetermined amount of force is applied. Therefore, in order to prevent such an accident, a projecting portion 17 having a protruding amount larger than that of the air / water feeding base 10 is provided in the vicinity of the air / water feeding base 10.

  The ultrasonic observation device 14 performs various controls of the ultrasonic endoscope 1, and for example, controls driving of an ultrasonic transducer 41 provided in a transducer unit (see reference numeral 30 described later) Then, the video signal is generated by performing signal processing of the electrical signal acquired by the drive control. The video signal generated by the ultrasonic observation apparatus 14 is output to a display device (not shown) that constitutes the ultrasonic endoscope apparatus. As a result, an ultrasonic tomographic image is displayed on the screen of the display device that has received this video signal.

  The insertion portion 2 of the ultrasonic endoscope 1 includes, in order from the distal end side, a distal end hard portion 21 formed of a rigid member, and a bending portion 22 configured to be freely bendable in the vertical direction and the left and right direction, for example. A long and flexible flexible tube portion 23 is provided continuously.

  A distal end cap 24 constituting an ultrasonic observation unit and a transducer unit 30 in which an ultrasonic transducer 41 is disposed in the distal end cap are provided on the distal end side of the distal end hard portion 21. A signal cable 91 extends from the vibrator unit 30. The signal cable 91 is inserted through the insertion portion 2, the operation portion 3, and the universal cord 4 and connected to the ultrasonic connector 8.

  On the universal cord 4 side of the operation unit 3, a bending operation knob 25 for performing the bending operation of the bending unit 22, an air supply / water supply suction button 26 for performing an air supply / water supply operation and a suction operation, respectively, are provided. A treatment instrument insertion port 27 for introducing a treatment instrument into the body cavity is provided on the insertion section 2 side of the operation section 3.

  As shown in FIG. 2, a slope portion 21b is formed on the distal end side of the distal end portion main body 21a constituting the distal end rigid portion 21. The inclined surface portion 21b has an illumination optical system arrangement hole (not shown) for arranging the illumination optical system constituting the endoscope observation unit and an opening portion of the observation optical system arrangement hole 21c for arranging the observation optical system. Is provided.

  Further, a vibrator unit arrangement hole (hereinafter abbreviated as a unit hole) 21d in which the vibrator unit 30 is arranged is formed in the tip end body 21a. A plurality of step portions are formed on the inner peripheral surface of the unit hole 21 d so as to substantially match the stepped outer shape of the vibrator unit 30. The diameters of the plurality of step portions are formed so as to gradually become smaller from the distal end side, which is the opening of the unit hole 21d, toward the proximal end side. A female screw 21e is formed in the vicinity of the opening of the unit hole 21d. The female screw 21e is screwed with a male screw provided on a ring member 81, which will be described later, for fixing the vibrator unit 30 to the tip end body 21a.

  Further, a cap disposing portion 21f in which a distal end cap 24 separate from the vibrator unit 30 is disposed on the opening side of the unit hole 21d formed in the distal end portion main body 21a. Reference numeral 21g represents a positioning surface, and the positioning surface 21g positions the vibrator unit 30 in the longitudinal axis direction. Specifically, a unit housing (to be described later) constituting the vibrator unit 30 on the positioning surface 21g, which is the surface of one step portion among the plurality of step portions formed on the inner peripheral surface of the unit hole 21d. By arranging the end face of the large diameter portion in contact with each other, the vibrator unit 30 is arranged in a predetermined state with respect to the tip portion main body 2a. Reference numeral 21h denotes a balloon placement circumferential groove in which a balloon (not shown) is placed.

  Illumination light supplied from the light source device 11 is transmitted through a light guide (not shown) that passes through the universal cord 4, the operation unit 3, and the insertion unit 2, and an illumination window (not shown) of the illumination optical system. It is emitted toward the observation site from the figure. An observation site such as an affected part in the body cavity is illuminated by the illumination light emitted from the illumination window.

  The optical image of the observation site illuminated by the illumination light passes through an observation window (not shown) and an objective lens, and images a charge coupled device (hereinafter referred to as a CCD) or the like disposed at the imaging position of the objective lens. An image is formed on an imaging surface of an element (not shown). The optical image formed on the imaging surface of the CCD is photoelectrically converted into an electric signal and transmitted to the video processor 12 through an imaging cable (not shown) extending from the CCD. The video processor 12 to which the electrical signal has been transmitted performs predetermined signal processing to generate a standard video signal, and outputs the video signal to a predetermined display device (not shown). As a result, the endoscopic observation image is displayed on the screen of the display device. The imaging cable is inserted through the insertion portion 2, the operation portion 3, and the universal cord 4 and is electrically connected to the electrical connector 7.

Here, the configuration of the vibrator unit 30 disposed in the unit hole 21d will be specifically described.
As shown in FIG. 3 to FIG. 4C, the transducer unit 30 includes an ultrasonic transducer unit 40, a slip ring unit 50, an encoder unit 60, a motor unit 70, the ultrasonic transducer unit 40, The slip ring part 50, the encoder part 60, and the unit housing 33 which is a housing | casing which integrates the motor part 70 are comprised. In the unit housing 33, the ultrasonic transducer section 40, the slip ring section 50, the encoder section 60, and the motor section 70 are disposed.

  The ultrasonic transducer section 40 is mainly composed of an ultrasonic transducer 41 and a transducer holding member 42 that is a rotated body on which the ultrasonic transducer 41 is disposed. The vibrator holding member 42 is provided with a vibrator shaft 43 that is a rotating shaft composed of a large diameter portion 43a and a small diameter portion 43b. Ultrasonic waves are transmitted from the transducer surface of the ultrasonic transducer 41 toward the living body, and ultrasonic echoes reflected by the living tissue are received.

  The slip ring portion 50 is mainly composed of a brush holder 51 having a through hole, a pair of ring members 52a and 52b, and brush members 53a and 53b that are in electrical contact with the ring members 52a and 52b, respectively. Yes. Protrusions 51a and 51b are formed on the front end surface and the base end surface of the brush holder 51, respectively. Extending from the slip ring portion 50 is a first signal cable 92 having one end of a signal line connected to the brush members 53a and 53b. Reference numeral 59 denotes an insulating resin member for sealing a signal line fixing portion which is a joint portion between the signal line 92a and a terminal (not shown).

  The encoder unit 60 is disposed so as to face a coupling 61 that is a shaft coupling, an encoder magnetizing drum (hereinafter abbreviated as a magnetizing drum) 62 that constitutes the encoder, and the magnetizing drum 62. It is mainly composed of an encoder sensor 63 to be described later. Reference numeral 63a denotes a substrate on which an encoder sensor (hereinafter abbreviated as a sensor) 63 is provided. The substrate 63a is provided with a signal line fixing portion to which a plurality of signal lines 93a are joined. The plurality of signal lines 93 a are collected and extended as a second signal cable 93. A motor drive line extending from the motor body (see reference numeral 72 in FIG. 6C) is inserted into the second signal cable 93.

  The coupling 61 integrally connects and fixes a small diameter portion 43b of the vibrator shaft 43 and a motor shaft 71 (to be described later) of the motor portion 70. The magnetizing drum 62 is made of resin and has a magnetized portion at a predetermined portion, and is fixed to the outer peripheral portion of the coupling 61. On the outer peripheral surfaces of the magnetizing drum 62 and the coupling 61, a magnetized part notifying part (for example, a marking line) serving as a mark for arranging the magnetized part provided in the magnetizing drum 62 in a predetermined state ( (Not shown) is provided.

  The motor unit 70 includes a motor main body 72 that is integral with an exterior member that is a drive motor having a motor shaft 71 that is integrally fixed to the coupling 61, and is integrally disposed on the outer peripheral surface of the tip end of the motor main body 72. It is mainly comprised by the elastic sheet member 73 which is the motor holding means formed in the sheet form provided. The elastic sheet member 73 is formed with a predetermined thickness by a flexible and deformable material such as a rubber member.

  A large-diameter portion 34, an intermediate-diameter portion 35, and a small-diameter portion 36 are formed in the unit housing 33 in order from the distal end side. The large diameter portion 34 is formed with a brush holder hole 34a in which the brush holder 51 is disposed. One end surface of the brush holder 51 is disposed in contact with the bottom surface of the brush holder hole 34a. A motor arrangement hole 36 a in which an elastic sheet 73 provided in a motor main body 72 constituting the motor unit 70 is arranged is formed inside the small diameter portion 36. The intermediate diameter portion 35 is formed with a communication hole 35a that allows the brush holder hole 34a of the large diameter portion 34 and the motor arrangement hole 36a of the small diameter portion 36 to communicate with each other. In the communication hole 35a, the coupling 61, the magnetizing drum 62, and the like are arranged.

  Circumferential grooves 34 b and 35 b are formed at predetermined positions on the side peripheral surfaces of the large diameter portion 34 and the intermediate diameter portion 35. In these circumferential grooves 34b and 35b, an insulating tape 37 is wound so as to insulate between the various signal line fixing portions provided in the unit housing 33 and the tip body 21a. The depth dimensions of the circumferential grooves 34b and 35b are set in advance so that the insulating tape 37 does not protrude from the circumferential surface when the insulating tape 37 is wound by a predetermined amount.

  The fixing ring member 81 is a member for integrally fixing the vibrator unit 30 arranged in the unit hole 21d to the distal end hard portion 21. A male screw 81 a is formed on the outer peripheral surface of the fixing ring member 81. The fixing ring member 81 is rotatably disposed on a protrusion 51 a formed on the brush holder 51.

  Reference numeral 90 denotes a cable protector, which is composed of, for example, a flexible wire cable 95 that is an elastically deformable linear member, and a cable fixing portion 96 provided on one end side of the wire cable 95. The other end of the wire cable 95 is integrally fixed by providing a joint 97 by soldering or the like in the small diameter portion 36 of the unit housing 33.

Here, the detail of each part 40, 50, 60, 70, 90 is demonstrated.
A relay substrate 44 is disposed on the back surface of the ultrasonic transducer 41 constituting the ultrasonic transducer section 40. The relay substrate 44 is provided with electrode patterns 44a and 44b. The end portions of the signal lines 45a and 45b of the ultrasonic cable 45 extending from the ultrasonic transducer 41 are electrically connected to the electrode patterns 44a and 44b, respectively, and one end portion is connected to the ring members 52a and 52b. The other ends of the signal lines 46a and 46b of the electrically connected slip ring cable 46 are electrically connected. The slip ring cables 46 a and 46 b are inserted through cable insertion holes 43 c formed in the vibrator shaft 43.

  The large-diameter portion 43a has an O-ring arrangement groove 43d in which an O-ring 47 is arranged. Reference numeral 48 denotes a sealing resin. The sealing resin 48 is composed of the electrodes 44a and 44b of the relay substrate 44, the ultrasonic cable 45 having the signal lines 45a and 45b, and the slip ring cable 46 having the signal lines 46a and 46b. 24 is prevented from touching the ultrasonic transmission medium filled in 24, and the opening of the cable insertion hole 43c is closed to prevent the ultrasonic transmission medium from entering the cable insertion hole 43c. It is to be applied to.

  A through hole is formed in the brush holder 51 of the slip ring portion 50. This through hole is a hole 54 in which the large-diameter portion 43a of the vibrator shaft 43 and the ring members 52a and 52b are disposed, and a communication hole 55 that connects the bottom surface of the hole portion 54 and the outside at the center portion. It consists of and. The communication hole 55 is arranged with a distal end portion 61 a of a coupling 61 that connects the small diameter portion 43 b and the motor shaft 71.

  On the other hand, the outer peripheral surface of the O-ring 47 arranged in the O-ring arrangement groove 43d formed in the large-diameter portion 43a is in close contact with the inner peripheral surface of the hole portion 54. As a result, water tightness between the hole 54 and the large diameter portion 43a is maintained, and the ultrasonic transmission medium in the tip cap 24 is prevented from flowing into the ring members 52a and 52b. Yes.

  In the present embodiment, as shown in FIG. 4B, the sliding bearing portion configured such that the outer peripheral surface of the large-diameter portion 43a is in sliding contact with the inner peripheral surface of the hole portion 54 of the brush holder 51, and the communication Provided on the inner peripheral surface of the hole 55 is a sliding bearing portion configured such that the outer peripheral surface of the distal end portion 61a of the coupling 61 is in sliding contact, and rotates the ultrasonic transducer 41 disposed on the transducer holding member. It is configured.

A modification will be described with reference to FIGS. 5 (a) to 5 (c).
When the vibrator shaft 43 of the vibrator holding member 42 on which the ultrasonic vibrator 41 is disposed is rotatably supported by two sliding bearing portions, for example, one side indicated by an arrow A in FIG. The sliding bearing portion may be configured as follows. That is, only the outer peripheral surface 43e arranged on the rear side of the O-ring 47 of the large diameter portion 43a is brought into sliding contact with the inner peripheral surface 54a of the hole portion 54 of the brush holder 51. As a result, the sliding resistance of the vibrator shaft 43 can be reduced.

  Further, in addition to FIG. 5A, a counterbore-shaped hole 51c may be formed in the protrusion 51b that constitutes the sliding bearing portion on the other side, as indicated by an arrow B in FIG. 5B. . As a result, the sliding area between the inner peripheral surface 55a of the communication hole 55 and the outer peripheral surface of the tip end portion of the coupling 61 can be reduced, and the sliding resistance can be further reduced.

  Further, the vibrator shaft 43 is rotatably supported by one sliding bearing portion. In that case, a gap is formed on the arrow A side in FIG. 5C, and the coupling 61 disposed on the inner peripheral surface 55a of the communication hole 55 on the arrow B side so as to cover the small diameter portion 43b. The outer peripheral surface of the tip part is brought into sliding contact to form a sliding bearing. As a result, the sliding resistance can be further reduced.

  Also, as shown in FIG. 4B, a driving force transmission mechanism is configured by connecting the narrow diameter portion 43b of the vibrator shaft 43 and the motor shaft 71 of the motor portion 70 by the coupling 61. . The vibrator shaft 43 is integrally fixed to the coupling 61 by a fastening member 65 such as a screw that is screwed into a female screw portion formed at a predetermined position on the outer peripheral surface of the coupling 61. On the other hand, the motor shaft 71 is integrally fixed to the coupling 61 with an adhesive (not shown).

  6A and 6B, the motor shaft 71a has a D-shaped cross section, and a hole in the coupling 61 in which the motor shaft 71a is disposed. 61a is also formed in a D shape. In this configuration, the outer shape of the hole 61a is formed larger than the outer shape of the motor shaft 71a to provide a gap. As a result, when the motor shaft 71a is rotating, the plane portion slides by this gap, so that the deviation of the rotation center between the motor shaft 71a and the coupling 61 is absorbed and the rotational load applied to the motor unit 70. On the other hand, the rotation of the motor shaft 71 is transmitted to the coupling 61 by the planar portion of the motor shaft 71a hitting the planar portion of the hole 61a.

  Further, as shown in the modification of FIG. 6 (c), the small-diameter portion 43b and the motor are configured by a three-member coupling mechanism 61A configured to be separated into three bodies and absorbing the center misalignment by sliding. The shaft 71 may be connected. The three-member coupling mechanism 61A includes a first tubular member 66 having a first hole 66a in which the small diameter portion 43b is disposed, and a second hole 67a in which the motor shaft 71 is disposed. 2 tubular members 67, and a connecting member 68 having shaft portions 68a and 68b disposed in the hole portion 67a and the hole portion 66a.

  As shown in FIG. 7A, the brush holder 51 has a substantially D-shaped cross section, and a brush mounting plane 51d is formed at a predetermined position. The brush holder 51 is formed with notches 51e for disposing the brush members 53a and 53b on the brush mounting plane 51d.

  Therefore, the brush members 53a and 53b can be disposed on the brush mounting plane 51d through the notch 51e. The brush members 53a and 53b are formed of an elastic conductive member, and are configured to be in electrical contact with the outer peripheral surfaces of the ring members 52a and 52b by a biasing force. Specifically, the initial bent shape of the brush members 53a and 53b is formed such that the bending angle θ is an acute angle as shown by the broken line, and the brush members 53a and 53b are in urging contact with the outer peripheral surfaces of the ring members 52a and 52b. In this state, the angle θ is set to be substantially a right angle.

  The brush members 53a and 53b provided on the brush mounting plane 51d are sealed by the insulating resin member 59, and an insulating tape 37 is wound on the outer side thereof. As a result, the insulation between the tip end main body 21a is made more reliable without increasing the diameter.

  As shown in FIG. 7B, the encoder 63 is provided with the sensor 63 so as to face the magnetized drum 62. The sensor 63 detects a magnetized portion provided on the magnetizing drum 62. The sensor 63 is mounted on a substrate 63a, and the substrate 63a is mounted and fixed on a sensor installation block 64 disposed at a predetermined position of the unit housing 33, whereby the magnetized drum 62 is shown in the drawing. Are arranged close to each other. A predetermined amount of insulating tape 37 is wound for the purpose of insulation between the signal line fixing portion to which the signal line 93a provided on the substrate 63a is joined and the tip end body 21a.

  As shown in FIG. 7C, the elastic sheet member 73 disposed at the distal end portion of the motor main body 72 constituting the motor portion 70 is disposed on the proximal end side inner peripheral surface of the unit housing 33. At a predetermined position on the outer peripheral surface of the unit housing 33, for example, three female screw portions are provided. By a tightening force of a fixing member 75 such as a screw which is a motor rotation locking means screwed into the female screw portion. The elastic sheet member 73 disposed in the motor main body 72 is pressed and fixed so as to prevent the motor main body 72 from rotating. Note that the pressing force of the fixing member 75 may be an amount of force that prevents the motor main body 72 from rotating when the motor is driven.

  The motor main body 72 disposed in the unit housing 33 can be adjusted in the arrangement position in the unit housing 33 by the amount of deformation of the elastic sheet member 73.

  Therefore, even when the center axis of the vibrator shaft 43 connected by the coupling 61 and the center axis of the motor shaft 71 are slightly decentered, by rotating the motor shaft 71, the motor shaft 71 is rotated. The motor main body 72 deforms the elastic sheet 73, the central axis of the motor shaft 71 and the central axis of the transducer shaft 43 coincide with each other, and the ultrasonic transducer 41 is rotated.

  Thus, even if there is a slight misalignment between the central axis of the vibrator shaft and the central axis of the motor shaft connected by the coupling, the motor unit is disposed in the housing via the elastic sheet. By switching the motor shaft from the stopped state to the rotating state, the motor housing moves so as to deform the elastic sheet, so that the central axis of the motor shaft and the central axis of the vibrator shaft are matched. be able to.

  As a result, the rotation of the motor shaft is transmitted to the transducer shaft without uneven rotation, and the ultrasonic transducer rotates in the best condition. Further, the rotational driving force of the drive motor is efficiently transmitted to the vibrator shaft. Furthermore, the center axis of the vibrator shaft and the center axis of the motor shaft are reliably prevented from being misaligned and a load is applied to the drive motor.

  In addition, when the motor unit is disposed in the housing via the elastic sheet, it is not necessary to finely adjust the center axis of the vibrator shaft and the central axis of the motor shaft. Can greatly improve the performance.

  The fixing of the motor unit 70 to the unit housing 33 is not limited to pressing the elastic sheet member 73 by the fixing member 75 described above, and is shown in FIGS. 8A and 8B. As shown in the drawing, a circumferential notch 36b communicating with the motor arrangement hole 36a is provided in the small diameter portion 36 of the unit housing 33, and the fixing member 75 is substituted for the notch 36b as a motor rotation locking means. Alternatively, a configuration may be provided in which the bobbin winding fixing portion 76 is provided. At this time, the spool fixing portion 76 is formed so as to press the elastic sheet member 73 with a pressing force that prevents the motor main body 72 from rotating when the motor is driven. As a result, the same operations and effects as described above can be obtained.

  Further, as shown in FIGS. 8C and 8D, the outer diameter of the motor main body 72 is slightly narrower than the inner diameter of the unit housing 33, and the outer peripheral surface side of the motor main body 72 is formed. A locking member 74 formed with a through hole 74a having a diameter larger than the outer dimension of a screw member, which will be described later, serving as a motor holding means is fixed by, for example, adhesion. In addition, instead of forming the circumferential cutout portion 36b at a predetermined position of the unit housing 33, a female screw portion 36c is formed, and a screw member 38 serving as a motor rotation locking means is screwed into the female screw portion 36c. You may make it the structure to make. In this screwed state, the tip of the screw member 38 protrudes a predetermined amount from the inner peripheral surface of the motor arrangement hole 36a. As a result, the distal end portion of the screw member 38 is loosely placed in a through hole 74 a formed in the locking member 74 fixed to the motor main body 72.

  According to this configuration, in the state in which the motor unit 70 is disposed in the motor arrangement hole 36a, the motor unit 70 has some backlash. However, in a state where the motor shaft 71 is rotated, the motor main body 72 is rotated and moved by the amount of rattling, and then is caught in the through hole 74a, that is, the screw member 38 is attached to the motor main body 72. The fixed locking member 74 comes into contact. Then, the rotational movement of the motor main body 72 is stopped, and the motor main body 72 is held with respect to the unit housing 33. At this time, the central axis of the vibrator shaft 43 connected by the coupling 61 and the central axis of the motor shaft 71 are in agreement with each other, and the same operations and effects as described above can be obtained.

  As shown in FIG. 7D, midway portions of the first signal cable 92 and the second signal cable 93 are integrally fixed to the cable fixing portion 96 of the cable protection portion 90 by, for example, a bobbin adhering portion 98. When the middle portions of these cables 91 and 92 are fixed to the cable fixing portion 96 with a bobbin, at least the signal lines 91a and 92a are fixed so that no load is applied to the signal line fixing portions of the signal lines 91a and 92a. In the vicinity of the part, a slack is provided.

  When the vibrator unit 30 configured as described above is disposed in the unit hole 21d of the tip body 21a, first, the vibrator unit 30 is substantially disposed in the unit hole 21d. Thereafter, the fixing ring member 81 is rotated using, for example, a square wrench, and the male screw 81a of the fixing ring member 81 is screwed into the female screw 21e formed in the unit hole 21d. Then, as the fixing ring member 81 is rotationally moved, the large-diameter end face of the large-diameter portion 34 provided in the unit housing 33 constituting the vibrator unit 30 is formed in the unit hole 21d. It will be in the state contact | abutted to the positioning surface 21g. This completes the fixing of the vibrator unit 30 to the tip end body 21a. At this time, the ultrasonic transducer 41 protrudes from the distal end surface of the distal end main body 21a by a predetermined amount.

  Thereafter, the distal end cap 24 is disposed on the cap disposing portion 21f of the distal end portion main body 21a so as to cover the ultrasonic transducer 41, and in this state, for example, a link-like attachment member 82 formed of stainless steel (see FIG. 3) ) In the cap arrangement portion 21f. As a result, the fixing of the distal end cap 24a to the distal end main body 21a is completed in a state where the distal end cap 24 is prevented from expanding. Thereafter, the ultrasonic transmission medium 28 is filled in the tip cap 24.

  Examples of the ultrasonic transmission medium 28 include liquid paraffin, water, carboxymethyl cellulose aqueous solution, and the like. And this ultrasonic transmission medium 28 is inject | poured from the front-end | tip opening 24a formed in the front-end | tip part of the front-end | tip cap 24, for example, as shown in FIG. The tip opening 24 a is water-tightly closed by the sealing member 29. The tip cap 24 is made of an ultrasonically transparent material such as low density polyethylene or polymethylpentene.

The ultrasonic endoscope 1 assembled in this way is used in combination with the ultrasonic observation apparatus 14.
That is, when a current is supplied to the motor unit 70 of the transducer unit 30 via the ultrasonic observation device 14, the motor shaft 71 of the motor unit 70 is rotated, and the rotation of the motor shaft 71 is coupled to the coupling 61. Is transmitted to the small-diameter portion 43b of the vibrator shaft 43. Then, the ultrasonic transducer 31 disposed on the transducer holding member 42 having the transducer shaft 43 is rotated and starts radial scanning.

  At this time, even if the center axis of the vibrator shaft 43 connected by the coupling 61 and the center axis of the motor shaft 71 are slightly shifted from each other, by rotating the motor shaft 71, The motor main body 72 deforms the elastic sheet 73, and the ultrasonic transducer 41 is rotated in the best state in which the central axis of the motor shaft 71 and the central axis of the transducer shaft 43 coincide.

  In the above-described embodiment, the driving force transmission mechanism is provided in the transducer unit 30 of the ultrasonic endoscope 1, but the driving force transmission mechanism is provided in the rotation treatment unit of the medical device shown in FIG. You may do it.

  As shown in FIG. 9, in this embodiment, the driving force transmission mechanism is provided in the rotary treatment instrument 100 that is a medical device. The rotary treatment instrument 100 includes a rotary blade 102 at the distal end portion of the insertion portion 101. The rotation treatment instrument 100 is mainly composed of a sheath 103 constituting the insertion portion 101 and a rotation treatment unit 104.

Specifically, the rotation treatment unit 104 includes the rotary blade 102, a motor unit 110,
It is comprised with the unit housing 105 by which this motor part 110 is arrange | positioned. In addition to the motor portion 110, the unit housing 105 is provided with a rotary blade bearing portion 106 that pivotally supports a rotary blade shaft portion 102a protruding from the rotary blade 102.

  The motor unit 110 includes a motor main body (not shown) 112 that is a drive motor having a motor shaft 111, a tubular motor housing 112 that constitutes the exterior of the motor main body, and an outer peripheral surface of the tip of the motor housing 112. It is mainly composed of an elastic sheet 113 which is a motor holding means formed in a sheet shape which is integrally disposed. The elastic sheet 113 is formed with a predetermined thickness by a flexible and deformable material such as a rubber member.

  An end portion of the rotary blade shaft portion 102 a supported by the rotary blade bearing portion 106 and an end portion of the motor shaft 111 are integrally connected and fixed by a coupling 107.

  The elastic sheet 113 disposed at the front end portion of the motor housing 112 constituting the motor unit 110 is disposed at a substantially central portion of the unit housing 105. Although not shown, for example, three female screw portions are provided at a predetermined position on the outer peripheral surface of the unit housing 105, and a fixing member such as a screw that is a motor rotation locking means screwed into the female screw portion. The motor housing 112 is fixed by the pressing force. The pressing force of the fixing member at this time may be a force that prevents the motor housing 112 from rotating when the motor is driven.

  The motor housing 112 disposed in the unit housing 105 can be adjusted in position within the unit housing 105 by the amount of deformation of the elastic sheet 113.

  Therefore, even if the center axis of the rotary blade shaft portion 102a integrally connected and fixed by the coupling 107 and the center axis of the motor shaft 111 are slightly decentered, the motor shaft 111 is brought into a rotating state. As a result, the motor housing 112 deforms the elastic sheet 113 so that the central axis of the motor shaft 111 and the central axis of the rotary blade shaft portion 102a coincide with each other to rotate, and the rotary blade 102 rotates. Is done.

  As described above, when the motor unit is disposed in the housing via the elastic sheet, there is a slight misalignment between the central axis of the rotary blade shaft unit and the central axis of the motor shaft connected by the coupling. However, by switching the motor shaft to the rotating state, the motor housing moves so as to deform the elastic sheet, and the central axis of the motor shaft and the central axis of the vibrator shaft can be made to coincide with each other. it can.

  As a result, the rotation of the motor shaft is transmitted to the transducer shaft without uneven rotation, and the ultrasonic transducer rotates in the best condition. Further, the rotational driving force of the drive motor is efficiently transmitted to the vibrator shaft. Furthermore, the center axis of the vibrator shaft and the center axis of the motor shaft are reliably prevented from being misaligned and a load is applied to the drive motor.

  Other operations and effects are the same as those of the driving force transmission mechanism of the ultrasonic endoscope.

  Reference numeral 109 denotes a guide wire. The guide wire 109 is inserted and disposed in a wire hole provided in the motor unit 110, the coupling 107, the rotary blade shaft portion 102a, and the rotary blade 102.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention.

The figure explaining the structure of the ultrasound diagnosing device containing the ultrasound endoscope of this embodiment Sectional drawing explaining the structure of the front-end | tip part main body The figure explaining the structure of the front-end | tip part of an ultrasonic endoscope The figure explaining the composition of a vibrator unit The figure explaining the other structural example of a slide bearing The figure explaining the other attachment structure of a motor shaft and a thin diameter part The figure explaining the cross-sectional shape in each cross-sectional line of FIG. The figure explaining the other attachment structure to the unit housing of a motor part The figure explaining the structure of the rotation treatment unit provided with the driving force transmission mechanism

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ultrasound endoscope 30 ... Vibrator unit 33 ... Unit housing 43 ... Vibrator shaft 43b ... Small diameter part 61 ... Coupling 70 ... Motor part 71 ... Motor shaft 72 ... Motor housing 73 ... Elastic sheet 75 ... Fixed member
Attorney Susumu Ito

Claims (2)

Arranged in a transducer holding member having at least a transducer shaft, which is disposed in a transducer unit disposition hole of the distal end rigid portion, and a distal end rigid portion constituting an insertion portion having a transducer unit disposition hole. Ultrasonic transducer, a drive motor for rotating the ultrasonic transducer, and a shaft coupling for connecting the rotational shaft of the drive motor and the transducer shaft to transmit the rotational force of the motor shaft to the transducer shaft An ultrasonic endoscope comprising a transducer unit configured by being disposed in a unit housing ,
In the configuration in which a gap is provided between the outer peripheral surface of the drive motor and the inner peripheral surface of the unit housing ,
Provided in the gap portion, integrally fixed to the outer peripheral surface of the drive motor, and in said unit housing, said driving motor so that the drive motor is capable eccentric with respect to the central axis within said unit housing Motor holding means for holding;
Motor rotation locking means for preventing the drive motor integrally fixed with the motor holding means from rotating within the unit housing when the drive motor is in a driving state;
The gap is an amount capable of absorbing the eccentricity between the motor shaft of the drive motor and the shaft of the vibrator shaft when the motor shaft of the drive motor connected to the vibrator shaft rotates. Ultrasound endoscope . The motor holding means is
An elastically deformable elastic sheet-like member that is disposed on the outer periphery of the drive motor;
A fixing member disposed inside the unit housing and pressing the elastic sheet-like member with a predetermined pressure;
The deformation amount of elastic sheets, the ultrasonic endoscope according to claim 1, characterized in that the amount of absorbing the eccentricity of the motor shaft of the shaft and the driving motor of the vibrator shaft.

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