JP2015116412A - Permanent magnet rotating mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a permanent magnet rotating mechanism capable of implementing downsizing while improving the operability and suppressing the lowering of the induction performance.SOLUTION: A permanent magnet rotating mechanism comprises: an external permanent magnet 25a for applying a magnetic field to a permanent magnet arranged within a medical device; a first rotation mechanism capable of rotating the external permanent magnet infinitely around a first rotational shaft which is orthogonal to a magnetization direction of the external permanent magnet; a second rotation mechanism capable of rotating the external permanent magnet infinitely around a second rotational shaft which is orthogonal to the first rotational shaft; a first drive unit for generating rotation power to rotate the first rotation mechanism; and a second drive unit for generating rotation power to rotate the second rotation mechanism. The second rotation mechanism is arranged on the first rotation mechanism and constitutes a differential mechanism together with the first rotation mechanism. The first and second drive units are arranged on an opposite side to the external permanent magnet along the second rotational shaft with respect to the first and second rotation mechanisms.

Description

  The present invention relates to a permanent magnet turning mechanism used in a magnetic guidance system that magnetically guides a medical device that is introduced into a subject and acquires information in the subject.

  Conventionally, in the field of endoscopes, development of capsule endoscopes having a size that can be introduced into the digestive tract of a subject such as a patient has been underway. A capsule endoscope has an imaging function and a wireless communication function inside a capsule-type housing. After being swallowed from the subject's mouth, the subject moves while moving in the digestive tract by peristalsis or the like. Sequentially acquire image data of an image inside the organ (hereinafter also referred to as an in-vivo image) and wirelessly transmit it to a receiving device outside the subject. Image data received by the receiving device is taken into the image display device and subjected to predetermined image processing. The in-vivo image is displayed as a still image or a moving image on the display based on the image data subjected to the predetermined image processing. A user such as a doctor or a nurse diagnoses the state of the organ of the subject by observing the in-vivo image displayed on the image display device.

  In recent years, there has been proposed a magnetic guidance system including a guidance device that guides a capsule endoscope inside a subject by magnetic force (hereinafter referred to as magnetic guidance) (see, for example, Patent Documents 1 and 2). In general, in such a magnetic guidance system, a permanent magnet (hereinafter also referred to as an internal permanent magnet) is provided inside a capsule endoscope. In addition, the guidance apparatus includes a magnetic field generation unit configured using an electromagnet in Patent Document 1 and a permanent magnet (hereinafter also referred to as an external permanent magnet) in Patent Document 2, and is a capsule-type endoscope introduced into the subject. A magnetic field is applied to the mirror, and the capsule endoscope is magnetically guided to a desired position or orientation by a magnetic attraction generated from the applied magnetic field. In this case, the magnetic guidance system is provided with a display unit that can receive the image data acquired by the capsule endoscope and display the in-vivo image in real time, and the user refers to the in-vivo image displayed on the display unit. However, the magnetic guidance of the capsule endoscope can be operated using the operation input unit provided in the magnetic guidance system.

Japanese Patent No. 4709594 JP 2008-503310 A

  In the technique disclosed in Patent Document 1, since the capsule endoscope is magnetically guided using an electromagnet, a cable connected to the electromagnet is disposed around the electromagnet. In addition, in order to control the position and posture of the capsule endoscope, a plurality of electromagnets must be arranged so that the magnetization directions are different. In this case, when a certain electromagnet is energized to generate a magnetic field, the uniformity of the magnetic field decreases due to the influence of neighboring electromagnets. Due to the reduction in the uniformity of the magnetic field, the guidance performance of the capsule endoscope may be reduced.

  On the other hand, in the technique disclosed in Patent Document 2, the capsule endoscope is magnetically guided using an external permanent magnet. However, when the magnetization direction is changed by moving or turning the external permanent magnet, the operation is convenient. If the rotating mechanism of the external permanent magnet is automated by a motor or the like in order to improve the performance, the magnetic field of the external permanent magnet is not uniform due to the influence of a nearby motor, and the guidance performance of the capsule endoscope is reduced. There was a risk of it.

  Further, in the technique disclosed in Patent Document 2, when automating the turning mechanism of the external permanent magnet, it is necessary to use a slip ring or the like in addition to the motor in order to turn the external permanent magnet infinitely. For this reason, there existed a problem that a turning mechanism will enlarge.

  The present invention has been made in view of the above, and it is an object of the present invention to provide a permanent magnet turning mechanism that can improve the operability, suppress a decrease in guidance performance, and realize downsizing. .

  In order to solve the above-described problems and achieve the object, a permanent magnet turning mechanism according to the present invention introduces a medical device in which a permanent magnet is arranged into a subject, and applies a magnetic field to the medical device. A permanent magnet turning mechanism used in a guidance device for guiding the medical device in the subject by applying an external permanent magnet that applies the magnetic field to the permanent magnet; and A first turning mechanism capable of turning the external permanent magnet indefinitely around a first rotation axis perpendicular to the magnetization direction; and the external permanent rotation around the second rotation axis perpendicular to the first rotation axis. A second turning mechanism capable of turning the magnet indefinitely, a first drive unit for generating rotational power for turning the first turning mechanism, and a first driving unit for generating rotational power for turning the second turning mechanism. Two drive units, The second turning mechanism is disposed on the first turning mechanism, and forms a differential mechanism with the first turning mechanism, and the first and second drive units are the first and second turning mechanisms. On the other hand, it is provided on the opposite side to the external permanent magnet along the second rotation axis.

  Further, the permanent magnet turning mechanism according to the present invention introduces the medical device in which the permanent magnet is disposed into the subject, and applies a magnetic field to the medical device, whereby the medical in the subject is performed. A permanent magnet turning mechanism used in a guidance device for guiding a device, wherein an external permanent magnet that applies the magnetic field to the permanent magnet, and a first rotation axis that is orthogonal to the magnetization direction of the external permanent magnet The external permanent magnet is held in a rotatable manner, and is held by the first turning portion that can turn around a second rotation axis that is orthogonal to the first rotation axis, and the first turning portion, A second turning part capable of turning around the second rotation axis independently of the first turning part; and rotational power around the second rotation axis applied to turning of the second turning part, Rotational power around the first rotation axis A power conversion unit that converts and turns the external permanent magnet around the first rotating shaft, a first drive unit that generates rotational power for turning the first turning unit, and the second turning A second drive unit that generates rotational power for turning the unit, and the first and second drive units are arranged along the second rotation axis with respect to the first and second turn units. It is provided on the opposite side to the external permanent magnet.

  The permanent magnet turning mechanism according to the present invention is characterized in that, in the above invention, the first and second turning parts and the power conversion part are made of a non-magnetic material.

  In the permanent magnet turning mechanism according to the present invention as set forth in the invention described above, the external permanent magnet has a columnar shape, and the first rotating shaft coincides with a longitudinal central axis of the external permanent magnet. And

  According to the present invention, while improving operability, it is possible to suppress a decrease in guidance performance and to achieve downsizing.

FIG. 1 is a diagram illustrating a configuration example of a magnetic induction system according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a configuration of a main part of the magnetic induction system shown in FIG. FIG. 3 is a schematic diagram for explaining an installation state of the external permanent magnet according to the embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing an example of the internal structure of the capsule endoscope shown in FIG. FIG. 5 is a perspective view schematically showing the configuration of the drive mechanism shown in FIG. FIG. 6 is a perspective view schematically showing the configuration of the turning unit shown in FIG. FIG. 7 is a partial cross-sectional view schematically showing the configuration of the turning unit shown in FIG. FIG. 8 is a diagram illustrating the turning of the external permanent magnet by the turning unit shown in FIG. FIG. 9 is a diagram illustrating the turning of the external permanent magnet by the turning unit shown in FIG. FIG. 10 is a diagram illustrating the turning of the external permanent magnet by the turning unit shown in FIG. FIG. 11 is a diagram illustrating the turning of the external permanent magnet by the turning unit shown in FIG. FIG. 12 is a diagram illustrating the turning of the external permanent magnet by the turning unit shown in FIG. FIG. 13 is a diagram for explaining the turning of the external permanent magnet by the turning unit shown in FIG. FIG. 14 is a diagram illustrating magnetic lines of force of the external permanent magnet provided in the turning unit shown in FIG. FIG. 15 is a perspective view schematically showing an example of a configuration in which a rotary motor is arranged in the vicinity of the turning unit. FIG. 16 is a diagram illustrating magnetic lines of force of the external permanent magnet provided in the turning unit shown in FIG.

  Hereinafter, a magnetic induction system according to an embodiment of the present invention will be described with reference to the drawings. In the following description, as a capsule medical device, a magnet for a capsule endoscope that uses a capsule endoscope that is orally introduced into a subject and floats in a liquid stored in the stomach of the subject. Although a guidance system is illustrated, this invention is not limited by this embodiment. That is, the present invention relates to various capsule medical devices such as a capsule endoscope that moves in the lumen from the esophagus of the subject to the anus and a capsule endoscope that is introduced from the anus together with an isotonic solution. It is possible to use. Moreover, in the following description, each figure has shown only the shape, magnitude | size, and positional relationship roughly so that the content of this invention can be understood. Therefore, the present invention is not limited only to the shape, size, and positional relationship illustrated in each drawing. In the description of the drawings, the same portions are denoted by the same reference numerals.

  FIG. 1 is a diagram illustrating a configuration example of a magnetic induction system according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a configuration of a main part of the magnetic induction system shown in FIG. As shown in FIG. 1, a capsule medical device guidance system 1 according to the first embodiment is a capsule medical device introduced into a body cavity of a subject, and is a capsule type medical device in which a permanent magnet is provided. The endoscope 10 includes a guidance device 20 that magnetically guides the capsule endoscope 10 introduced into the subject by generating a three-dimensional magnetic field 100.

  The capsule endoscope 10 is introduced into the organ of the subject together with a predetermined liquid by oral ingestion or the like, moves inside the digestive tract, and is finally discharged to the outside of the subject. In the meantime, the capsule endoscope 10 floats in the liquid introduced into the organ of the subject (for example, inside the stomach), sequentially images the inside of the subject while being magnetically guided by the magnetic field 100, and the in-vivo image acquired by the imaging. The image information (image data) corresponding to is sequentially wirelessly transmitted. The detailed structure of the capsule endoscope 10 will be described later.

  The guidance device 20 performs wireless communication with the capsule endoscope 10 and receives a wireless signal including image information acquired by the capsule endoscope 10 and receives from the capsule endoscope 10. Based on the obtained radio signal, the position detection unit 22 for detecting the position of the capsule endoscope 10 in the subject, and the image information is acquired from the radio signal received by the reception unit 21, and a predetermined signal is transmitted to the image information. The in-vivo image is displayed on the screen by performing the processing, and the display unit 23 that displays the position of the capsule endoscope 10 in the subject on the screen, and the input of information for instructing various operations in the capsule medical device guidance system 1 An operation input unit 24 that receives the capsule endoscope 10, a guidance magnetic field generation unit 25 that generates a magnetic field 100 for guiding the capsule endoscope 10, a control unit 26 that controls these units, And a storage unit 27 for storing an image information captured by the mirror 10.

  The receiving unit 21 includes a plurality of antennas 21a, and sequentially receives wireless signals from the capsule endoscope 10 via the plurality of antennas 21a. The receiving unit 21 selects the antenna having the highest received electric field strength from the plurality of antennas 21a, and performs a demodulation process or the like on the radio signal from the capsule endoscope 10 received via the selected antenna. Thereby, the receiving unit 21 extracts image data related to the inside of the subject from this wireless signal. The receiving unit 21 outputs an image signal including the extracted image data to the display unit 23.

  The position detection unit 22 performs calculation for estimating the position of the capsule endoscope 10 in the subject based on the signal strength of the radio signal received by the reception unit 21.

  The display unit 23 includes various displays such as a liquid crystal display, and generates a screen including an in-vivo image based on the image data input from the receiving unit 21 and other various information and displays the screen on the display. Specifically, the display unit 23 displays, for example, an in-vivo image group of the subject imaged by the capsule endoscope 10, and information on the position and posture of the capsule endoscope 10 and information on guidance operation. indicate. At this time, the display unit 23 may display the position and posture of the capsule endoscope 10 estimated from the magnetic field 100 generated by the guidance device 20, or based on the position detection result of the position detection unit 22. A position in the subject corresponding to the in-vivo image being displayed may be displayed on the screen. The display unit 23 displays, for example, a reduced image of the in-vivo image selected under the control of the control unit 26, patient information, examination information, and the like of the subject.

  The operation input unit 24 is realized by an input device such as a joystick, a console with various buttons and various switches, a keyboard, and the like, and provides guidance information for guiding the capsule endoscope 10 magnetically and the guidance device 20. And receiving various information such as setting information for setting a predetermined mode. The guidance instruction information is information for controlling the posture and position of the capsule endoscope 10 that is the object of the magnetic guidance operation. Specifically, the guidance instruction information includes an operation for changing the position of the capsule endoscope 10 and a capsule type. Information on the operation of changing the tilt angle (angle with respect to the vertical axis) of the endoscope 10 and the operation of changing the azimuth angle (angle around the vertical axis) of the field of view of the capsule endoscope 10 (imaging unit 11 described later). Information about In the following, the azimuth angle of the visual field is simply referred to as azimuth angle. The operation input unit 24 inputs the received information to the control unit 26.

  The induced magnetic field generation unit 25 generates a magnetic field for changing the position, tilt angle, and azimuth angle of the capsule endoscope 10 introduced into the subject relative to the subject. More specifically, the induction magnetic field generation unit 25 includes an external permanent magnet 25a as a magnetic field generation unit that generates a magnetic field, a planar position change unit 25b as a control mechanism that translates and rotates the external permanent magnet 25a, and a vertical position change unit. 25c and a turning angle changing unit 25d. The external permanent magnet 25a is realized, for example, by a bar magnet having a substantially bar shape (octagonal column shape) in which a cross section having a plane perpendicular to the longitudinal direction as an cut surface forms an octagon. Further, the external permanent magnet 25a is provided with an N pole and an S pole so that the magnetization direction is perpendicular to the longitudinal direction of the external permanent magnet 25a.

  FIG. 3 is a schematic diagram for explaining an installation state of the external permanent magnet 25a. In FIG. 3, with reference to the arrangement of the external permanent magnets 25a in the initial state, the directions orthogonal to each other in the plane (horizontal plane) orthogonal to the magnetization direction at this time are the X-axis direction, the Y-axis direction, and the magnetization direction, respectively. The direction parallel to is the Z-axis direction. The external permanent magnet 25a is movable in the X-axis, Y-axis, and Z-axis directions under the control of a position changing unit described later. Further, the external permanent magnet 25a passes through the center of the external permanent magnet 25a and rotates around the axis parallel to the magnetization direction (roll rotation), passes through the center of the external permanent magnet 25a, and has a magnetization direction. Rotation (yaw rotation) with the axis orthogonal to the rotation axis.

  The plane position changing unit 25b performs control to translate the external permanent magnet 25a in the horizontal plane. That is, the movement is controlled in the horizontal plane while the relative positions of the two magnetic poles magnetized in the external permanent magnet 25a are maintained.

  The vertical position changing unit 25c performs control to translate the external permanent magnet 25a along the vertical direction.

  The turning angle changing unit 25d controls the turning of the permanent magnet in the vertical plane including the external permanent magnet 25a to change the angle of the magnetization direction with respect to the horizontal plane, and the vertical axis passing through the center of the external permanent magnet 25a. Is controlled to turn the external permanent magnet 25a. The turning angle changing unit 25d preferably turns the external permanent magnet 25a with respect to an axis parallel to the capsule facing surface and perpendicular to the magnetization direction and passing through the center of the external permanent magnet 25a. For example, under the control of the turning angle changing unit 25d, the external permanent magnet 25a is turned at a predetermined turning angle, and the external permanent magnet 25a is rotated with respect to the rotating shaft in a state where the angle of the rotating shaft with respect to the reference arrangement is changed. Thus, the tilt angle and azimuth angle of the capsule endoscope 10 constrained by the magnetic field generated by the external permanent magnet 25a can be changed.

  The control unit 26 controls the operation of each unit of the guidance magnetic field generation unit 25 based on the detection result of the position detection unit 22 and the guidance instruction information received by the operation input unit 24, so that the capsule endoscope 10 is moved to the user. Guide to the desired position and posture.

  The storage unit 27 stores information such as various programs and various parameters for the control unit 26 to control each unit of the guidance device 20 in addition to the image data of the in-vivo image group of the subject imaged by the capsule endoscope 10. To do. The storage unit 27 is realized using a storage medium that stores information in a rewritable manner such as a flash memory or a hard disk.

  Next, the structure of the capsule endoscope 10 will be described. FIG. 4 is a schematic cross-sectional view showing an example of the internal structure of the capsule endoscope 10. As shown in FIG. 4, the capsule endoscope 10 images subjects in different imaging directions with a capsule-type housing 11 that is an exterior body that is formed in a size that can be easily introduced into the organ of a subject. And an imaging unit 12 that generates image information. The capsule endoscope 10 includes a wireless communication unit 16 that wirelessly transmits image information generated by the imaging unit 11 to the outside, a control unit 17 that controls each component of the capsule endoscope 10, and a capsule. And a power supply unit 18 that supplies power to each component of the mold endoscope 10. Furthermore, the capsule endoscope 10 includes a permanent magnet 19 for enabling magnetic guidance by the guidance device 20.

  The capsule housing 11 is an outer case formed in a size that can be introduced into the organ of a subject, and is realized by closing the open end of the cylindrical housing 11a with a dome-shaped housing 11b. . The dome-shaped housing 11b is a dome-shaped optical member that is transparent to light of a predetermined wavelength band such as visible light. The cylindrical casing 11a is a colored casing that is substantially opaque to visible light. As shown in FIG. 4, a capsule-type casing 11 formed by the cylindrical casing 11a and the dome-shaped casing 11b includes an imaging unit 12, a wireless communication unit 16, a control unit 17, a power supply unit 18, and a permanent magnet. 19 is contained in a liquid-tight manner.

  The imaging unit 12 includes an illumination unit 13 such as an LED, an optical system 14 such as a condensing lens, and an imaging element 15 including an image sensor such as a CMOS or a CCD. The illuminating unit 13 emits illumination light such as white light to the imaging field of the imaging device 15 and illuminates the subject in the imaging field through the dome-shaped casing 11b. The optical system 14 condenses the reflected light from the imaging field of view on the imaging surface of the imaging device 15 to form a subject image in the imaging field of view. The imaging element 15 receives reflected light from the imaging field focused on the imaging surface, performs photoelectric conversion processing on the received optical signal, and obtains image information representing the subject image in the imaging field, that is, the in-vivo image of the subject. Generate.

  As shown in FIG. 4, when the capsule endoscope 10 is a binocular capsule medical device that images the front and rear in the long axis La direction, the imaging unit 12 is configured such that each optical axis is a capsule type. The housing 11 is arranged so as to be substantially parallel or substantially coincident with the long axis La that is the central axis in the longitudinal direction of the casing 11 and the imaging fields of view are directed in opposite directions. That is, the imaging unit 12 is mounted so that the imaging surface of the imaging element 15 is orthogonal to the long axis La.

  The wireless communication unit 16 includes an antenna 16a, and sequentially wirelessly transmits image information acquired by the imaging unit 12 described above to the outside via the antenna 16a. Specifically, the wireless communication unit 16 acquires an image signal based on the image information generated by the imaging unit 12 from the control unit 17, modulates the image signal, and modulates the image signal. Generate a radio signal. The wireless communication unit 16 transmits this wireless signal to the external receiving unit 21 via the antenna 16a.

  The control unit 17 controls each operation of the imaging unit 12 and the wireless communication unit 16 and controls input / output of signals between these components. Specifically, the control unit 17 causes the image sensor 15 to image a subject in the imaging field illuminated by the illumination unit 13. The control unit 17 has a signal processing function for generating an image signal. The control unit 17 acquires image information from the image sensor 15 and performs predetermined signal processing on the image information each time to generate an image signal including image data. Further, the control unit 17 controls the wireless communication unit 16 so as to sequentially wirelessly transmit such image signals to the outside along a time series.

  The power supply unit 18 is a power storage unit such as a button-type battery or a capacitor, and includes a switch unit such as a magnetic switch or an optical switch. The power supply unit 18 switches the power supply on / off state by a magnetic field applied from the outside, and in the case of the on state, the power of the power storage unit is transmitted to each component of the capsule endoscope 10 (the imaging unit 12, the wireless communication unit 16, and the It supplies to the control part 17) suitably. Further, the power supply unit 18 stops the power supply to each component of the capsule endoscope 10 when it is in the off state.

  The permanent magnet 19 is for enabling the magnetic guidance of the capsule endoscope 10 by the magnetic field 100 generated by the induction magnetic field generation unit 25, and the magnetization direction has an inclination with respect to the long axis La. It is fixedly arranged inside the capsule-type housing 12. Specifically, the permanent magnet 19 is arranged so that the magnetization direction is orthogonal to the long axis La. The permanent magnet 19 operates following a magnetic field applied from the outside. As a result, magnetic guidance of the capsule endoscope 10 by the guidance magnetic field generation unit 25 is realized.

  As shown in FIG. 2, in the guidance device 20, at least an external permanent magnet 25 a and a drive mechanism 110 that moves or turns the external permanent magnet 25 a include a bed 120 as a mounting table on which a subject is mounted. Provided inside.

  The drive mechanism 110 can move the external permanent magnet 25a on a plane parallel to a predetermined plane (for example, the mounting surface of the subject), and can move the external permanent magnet 25a in a direction orthogonal to the plane. A movable part 200, a turning part 210 (permanent magnet turning mechanism) that is held by the moving part 200, holds an external permanent magnet 25a, and can turn the external permanent magnet 25a around a predetermined rotation axis. Have.

  The moving unit 200 holds the swivel unit 210 and moves the swivel unit 210 in a predetermined direction (in this embodiment, the Z-axis direction in FIG. 2), and a Z-axis direction move. An X-axis direction moving unit 202 that supports the unit 201 and is movable in a direction orthogonal to the moving direction of the swivel unit 210 of the Z-axis direction moving unit 201 (in this embodiment, the X-axis direction in FIG. 2); A Y-axis that supports the X-axis direction moving unit 202 and that can move the X-axis direction moving unit 202 in a direction orthogonal to the moving direction of the Z-axis direction moving unit 201 (in this embodiment, the Y-axis direction in FIG. 2) Direction moving unit 203.

  FIG. 5 is a perspective view schematically showing the configuration of the drive mechanism shown in FIG. The X-axis direction moving part 202 has a substantially plate shape extending in the direction (X-axis direction) in which the Z-axis direction moving part 201 is moved.

  The Y-axis direction moving unit 203 includes a columnar first member 203a and a second member 203b extending in a direction (Y-axis direction) in which the X-axis direction moving unit 202 is moved. The first member 203a and the second member 203b respectively hold both end portions in the longitudinal direction (X-axis direction) of the X-direction moving unit 202.

  Based on the information received by the operation input unit 24, the moving unit 200 controls the Z-axis direction moving unit 201, the X-axis under the control of the plane position changing unit 25b, the vertical position changing unit 25c, and the turning angle changing unit 25d. The turning unit 210 can be disposed at a predetermined position by driving the direction moving unit 202 and the Y-axis direction moving unit 203 to move each moving unit or the turning unit 210. The moving unit 200 is realized by any mechanism such as a linear motion mechanism using a shaft, a linear motion mechanism using a linear guide and a ball screw, and a linear motion mechanism using a linear guide and a timing belt.

  FIG. 6 is a perspective view schematically showing the configuration of the turning unit shown in FIG. FIG. 7 is a partial cross-sectional view schematically showing the configuration of the turning unit shown in FIG. The turning portion 210 is orthogonal to the magnetization direction of the external permanent magnet 25a, the base portion 211 that is held by the Z-direction moving portion 201 and has a convex portion 211a that protrudes in a columnar shape at the center, and the external permanent magnet 25a. An external permanent magnet 25a is rotatably held around an axis (first rotation axis), and is attached to a first turning part 212 and a first turning part 212 that are rotatably attached to the base part 211. And a second swivel portion 213 that is relatively rotatably attached.

  Further, the turning unit 210 is driven under the control of the turning angle changing unit 25d, and the rotating motor 221 (first driving unit) that generates rotational power for turning the first turning unit 212, and the turning angle change. A rotary motor 222 (second drive unit) that is driven under the control of the unit 25d and generates rotational power for turning the second turning unit 213.

  The first turning portion 212 has a cylindrical shape, and is formed with a hollow portion 212a that is a hollow space of the cylinder, and a first tooth portion 212b that has a shape in which irregularities are repeated along the outer periphery. The first turning portion 212 rotates with respect to the base portion 211 using the central axis (cylindrical central axis R1) of the hollow portion 212a as a rotation axis.

  The second turning portion 213 has a cylindrical shape, and is a hollow portion 213a that is a hollow space of the cylinder, and one end side in the direction of the central axis R1 (second rotation axis) of the cylinder, along the outer periphery. A second tooth portion 213b having a shape with repeated unevenness and a third tooth portion 213c having a shape with repeated unevenness along the outer periphery on the other end side in the central axis direction of the cylinder are formed. Yes. The second turning unit 213 rotates with respect to the first turning unit 212 using the central axis of the hollow portion 213a (cylindrical center axis R1) as a rotation axis. In the present embodiment, description will be made assuming that the central axis of the hollow portion 212a and the central axis of the hollow portion 213a coincide with each other and pass through the center of gravity of the external permanent magnet 25a.

  The first turning portion 212 has substantially plate-like holding portions 214 and 215 that extend from the first turning portion 212 in the direction of the central axis R1 and hold both ends of the external permanent magnet 25a in the longitudinal direction.

  The holding parts 214 and 215 extend in a plate shape from one end side of the first turning part 212 in the direction of the central axis R1 along the direction of the central axis R1. The holding portion 214 is provided with a protruding portion 216 that protrudes outward from the plate surface of the holding portion 214.

  The protrusion 216 is inserted through a rotation shaft 217 that is rotatable with respect to the protrusion 216. One end of the rotating shaft 217 is provided with a first gear 217a that has a shape in which unevenness is repeated along the outer periphery and can mesh with the third tooth portion 213c. At the other end of the rotating shaft 217, there is provided a second gear 217b having a weight shape and having a shape in which the weight-like slope has repeated unevenness.

  The external permanent magnet 25a is attached with a substantially rod-like support portion 218 that penetrates in the longitudinal direction of the external permanent magnet 25a and is rotatably supported by the holding portions 214 and 215. The support portion 218 has a central axis R2 (first rotation) whose central axis passes through the center of gravity of the external permanent magnet 25a, is orthogonal to the magnetization direction of the external permanent magnet 25a, and is parallel to the longitudinal direction of the external permanent magnet 25a. Axis). Further, the straight line that coincides with the central axis of the support portion 218 is orthogonal to the straight line that coincides with the central axis of the rotation shaft 217. Between the holding portions 214 and 215 and the support portion 218, bearings B1 and B2 are provided. The bearings B1 and B2 are realized using, for example, a sliding bearing.

  In addition, a third gear 218a is provided at the tip of the support portion 218. The third gear 218a has a shape in which the weight-like inclined surface has repeated irregularities that can mesh with the second gear 217b. The support unit 218 rotates (rotates) around its own central axis as a rotation axis according to the rotation of the third gear 218a. The second gear 217b and the third gear 218a are realized by using bevel gears, for example.

  Here, the first turning portion 212, the holding portions 214 and 215, and the support portion 218 constitute a first turning mechanism. The second turning unit 213, the rotation shaft 217, the first gear 217a, the second gear 217b, the support unit 218, and the third gear 218a constitute a second turning mechanism. A differential mechanism is configured by the first and second turning mechanisms. Further, the rotary shaft 217, the first gear 217a, the second gear 217b, the support portion 218, and the third gear 218a constitute a power conversion portion.

  Here, an annular bearing B3 is provided between the convex part 211a of the base part 211 and the hollow part 212a of the first turning part 212, and the base part 211 and the first turning part 212 are connected. . An annular bearing B4 is provided between the first turning part 212 and the second turning part 213. Thereby, the second turning unit 213 can turn independently of the first turning unit 212. In addition, annular bearings B5 and B6 are provided between the protruding portion 216 and the rotating shaft 217. The bearings B3 to B6 are realized using, for example, a sliding bearing or a rolling bearing.

  The rotary motors 221 and 222 are provided on the side opposite to the external permanent magnet 25a with respect to the first turning part 212 and the second turning part 213 when viewed along the central axis R1.

  In the swivel unit 210, all components other than the external permanent magnet 25a and the rotary motors 221 and 222 are formed using a non-magnetic material.

  8-10 is a figure explaining rotation of the external permanent magnet by the turning part shown in FIG. The swivel unit 210 rotates the first swivel unit 212 and / or the second swivel unit 213 by driving the rotation motor 221 and / or the rotation motor 222 under the control of the swivel angle changing unit 25d. 25a is turned around a predetermined rotation axis.

  Specifically, gears 221 a and 222 a that are rotated by driving the rotary motors 221 and 222 are provided at the tips of the rotary motors 221 and 222, respectively. The gear 221a and the gear 222a mesh with the first tooth portion 212b and the second tooth portion 213b, respectively.

  Below, each operation | movement is demonstrated with reference to drawings about the case where the external permanent magnet 25a carries out a yaw rotation and / or a roll rotation.

(1) Case where External Permanent Magnet 25a Turns Yaw and Rolls A case where the external permanent magnet 25a turns yaw and rolls will be described with reference to FIGS. In this case, the rotary motor 221 is driven and the rotary motor 222 is not driven.

(Operation 1-1)
When the gear 221a is rotated in the direction of the arrow Q11 in FIG. 8 by driving the rotary motor 221, the first turning portion 212 is rotated in the direction of the arrow T11 in FIG. 8, and the holding portions 214 and 215 are linked to the arrow T11 in conjunction with this. , The external permanent magnet 25a yaw-turns in the direction of the arrow T11 with the central axis R1 as the rotation axis (second rotation axis).

  At this time, along with the rotation of the holding portion 214, the protruding portion 216 also rotates in the direction of the arrow T11 with the central axis R1 as the rotation axis. When the protrusion 216 rotates in the direction of the arrow T11, the rotation shaft 217 also rotates in the direction of the arrow T11 with the central axis R1 as the rotation axis, so the first gear 217a follows the second tooth portion 213b of the second turning portion 213. And moving while rotating in the direction of arrow Q21 in FIG. As a result, the second gear 217b rotates in the direction of the arrow Q21 in conjunction with the rotation of the first gear 217a. When the second gear 217b rotates in the direction of the arrow Q21, the third gear 218a rotates in the direction of the arrow Q31. As a result, the external permanent magnet 25a is orthogonal to the magnetization direction and the longitudinal direction of the external permanent magnet 25a. It rolls (rotates) in the direction of arrow T21 with the parallel central axis R2 as the rotation axis.

(Operation 1-2)
When the gear 221a is rotated in the direction of the arrow Q12 in FIG. 9 by driving the rotary motor 221, the first turning portion 212 is rotated in the direction of the arrow T12 in FIG. 9, and the holding portions 214 and 215 are interlocked with the arrow T12. , The external permanent magnet 25a yaw-turns in the direction of the arrow T12 with the central axis R1 as the rotation axis.

  At this time, with the rotation of the holding portion 214, the protruding portion 216 also rotates in the direction of the arrow T12 with the central axis R1 as the rotation axis. When the projecting portion 216 rotates in the direction of the arrow T12, the rotation shaft 217 also rotates in the direction of the arrow T12 with the central axis R1 as the rotation axis, so the first gear 217a follows the second tooth portion 213b of the second turning portion 213. And moving while rotating in the direction of arrow Q22 in FIG. As a result, the second gear 217b rotates in the direction of the arrow Q22 in conjunction with the rotation of the first gear 217a. When the second gear 217b rotates in the direction of arrow Q22, the third gear 218a rotates in the direction of arrow Q32. As a result, the external permanent magnet 25a rolls in the direction of arrow T22 about the central axis R2 as the rotation axis. .

(2) Case where the external permanent magnet 25a performs only roll turning A case where the external permanent magnet 25a performs only roll turning will be described with reference to FIGS. In this case, the rotary motor 222 is driven and the rotary motor 221 is not driven.

(Operation 2-1)
When the gear 222a rotates in the direction of the arrow Q41 in FIG. 10 by driving the rotary motor 222, the second turning portion 213 rotates in the direction of the arrow Q51 in FIG. 10, and in conjunction with this, the first gear 217a moves in the direction of the arrow Q21. Rotate in the direction. When the second gear 217b rotates in the direction of the arrow Q21 in conjunction with the rotation of the first gear 217a, the third gear 218a rotates in the direction of the arrow Q31. As a result, the external permanent magnet 25a rotates the central axis R2. The roll is turned in the direction of arrow T21 as an axis.

(Operation 2-2)
When the gear 222a rotates in the direction of the arrow Q42 in FIG. 11 by driving the rotary motor 222, the second turning portion 213 rotates in the direction of the arrow Q52 in FIG. 11, and in conjunction with this, the first gear 217a moves in the direction of the arrow Q22. Rotate in the direction. When the second gear 217b rotates in the direction of the arrow Q22 in conjunction with the rotation of the first gear 217a, the third gear 218a rotates in the direction of the arrow Q32. As a result, the external permanent magnet 25a rotates the central axis R2. The roll is turned in the direction of arrow T22 as an axis.

(3) When the external permanent magnet 25a performs only yaw turning A case where the external permanent magnet 25a performs only yaw turning will be described with reference to FIGS. In this case, the rotary motor 221 and the rotary motor 222 are driven.

(Operation 3-1)
When the gear 221a is rotated in the direction of the arrow Q11 in FIG. 12 by driving the rotary motor 221, the first turning portion 212 is rotated in the direction of the arrow T11 in FIG. 12, and the holding portions 214 and 215 are interlocked with the arrow T11. , The external permanent magnet 25a yaw-turns in the direction of the arrow T11 with the central axis R1 as the rotation axis. As the holding portion 214 rotates, the protrusion 216 also rotates in the direction of the arrow T11 with the central axis R1 as the rotation axis.

  Here, when the gear 222a rotates in the direction of the arrow Q42 in FIG. 12 by driving the rotary motor 222, the second turning portion 213 rotates in the direction of the arrow Q52 in FIG. At this time, if the rotation motors 221 and 222 are controlled so that the rotation speeds of the first turning unit 212 and the second turning unit 213 are the same, the first gear 217a is moved around the central axis of the rotating shaft 217. Without rotating, it rotates in the direction of arrow T11 with the central axis R1 as the rotation axis. Therefore, the external permanent magnet 25a performs only the yaw rotation in the direction of the arrow T11 without performing the roll rotation.

(Operation 3-2)
When the gear 221a is rotated in the direction of the arrow Q12 in FIG. 13 by driving the rotary motor 221, the first turning portion 212 is rotated in the direction of the arrow T12 in FIG. 13, and the holding portions 214 and 215 are interlocked with the arrow T12. , The external permanent magnet 25a yaw-turns in the direction of the arrow T12 with the central axis R1 as the rotation axis. As the holding portion 214 rotates, the protrusion 216 also rotates in the direction of the arrow T12 with the central axis R1 as the rotation axis.

  Here, when the gear 222a is rotated in the direction of the arrow Q41 in FIG. 13 by driving the rotary motor 222, the second turning portion 213 is rotated in the direction of the arrow Q51 in FIG. At this time, if the rotation motors 221 and 222 are controlled so that the rotation speeds of the first turning unit 212 and the second turning unit 213 are the same, the first gear 217a is moved around the central axis of the rotating shaft 217. Without rotating, it rotates in the direction of arrow T12 with the central axis R1 as the rotation axis. Therefore, the external permanent magnet 25a performs only the yaw rotation in the direction of the arrow T12 without performing the roll rotation.

  In operation 3, by adjusting the rotational speeds of the rotary motors 221 and 222, the turning amounts (angles) at which the external permanent magnet 25a turns by yaw and roll can be made different from each other.

  FIG. 14 is a diagram illustrating magnetic lines of force of the external permanent magnet provided in the turning unit shown in FIG. In FIG. 14, the magnetic field lines of the magnetic field generated by the external permanent magnet 25a are schematically shown, and it is assumed that there are an N pole at the top and a S pole at the bottom. As shown in FIG. 14, in the turning unit 210 according to the present embodiment, the rotary motors 221 and 222 for turning the external permanent magnet 25a are located at a position away from the external permanent magnet 25a. For this reason, it is difficult for the rotary motors 221 and 222 to receive the distortion of the magnetic field. In particular, the capsule endoscope 10 is not affected by the magnetic field above the external permanent magnet 25a, that is, on the side where the capsule endoscope 10 is arranged, even when the roll or yaw is turned. Can be accurately controlled.

  On the other hand, the conventional structure which has arrange | positioned the rotation motor in the vicinity of a turning part is demonstrated. FIG. 15 is a perspective view schematically showing an example of a configuration in which a rotary motor is arranged in the vicinity of the turning unit. FIG. 16 is a diagram illustrating magnetic lines of force of the external permanent magnet provided in the turning unit shown in FIG. In addition, the same code | symbol is attached | subjected to the structure similar to the turning part 210 mentioned above. A conventional swivel unit 300 shown in FIG. 15 is provided on the upper surface of a base part 301 and a first swivel part 302 that is rotatably held by the base part 301 and has a first tooth part 302a that can mesh with a gear 221a. As a configuration for rotating the external permanent magnet 25a by yaw, a rotary motor 303 having a gear 303a at the tip is attached.

  In addition, a third gear 304 having a cylindrical shape and a shape in which irregularities are repeated along the outer periphery is provided at the tip of the support portion 218. The gear 303a and the third gear 304 are configured such that their rotational power is transmitted by the conductive belt 305. With this configuration, the third gear 304 can be rotated by rotating the gear 303a by the rotary motor 303, and the external permanent magnet 25a can be turned (rolled). For example, as shown in FIG. 16, electric power is transmitted to the rotary motor 303 via a slip ring 306.

  FIG. 16 schematically shows magnetic field lines generated by the external permanent magnet 25a. As shown in FIG. 16, in the conventional turning unit 300, a rotary motor 303 for turning the external permanent magnet 25a is provided adjacent to the external permanent magnet 25a. The wiring connected to 303 is likely to be subjected to magnetic field distortion. In particular, since distortion of the magnetic field is generated above the external permanent magnet 25a, that is, on the side where the capsule endoscope 10 is disposed, when the roll or yaw is swung, the distortion of the capsule endoscope 10 is caused by this distortion. In some cases, the posture could not be controlled accurately.

  According to the present embodiment described above, the yaw turning mechanism (first turning mechanism) for turning the external permanent magnet 25a yaw and the roll turning mechanism (second turning mechanism) for turning the external permanent magnet 25a are differential mechanisms. The rotary motors 221 and 222 are disposed at positions that are opposite to the side where the capsule endoscope 10 is disposed and do not affect the magnetic field in the region including the capsule endoscope 10, Since the external permanent magnet 25a is turned by yaw or roll by the rotary motors 221 and 222, it is possible to improve the operability of the magnetic guidance system by the user and suppress the deterioration of the guidance performance.

  Further, according to the above-described embodiment, the rotary motor 221 is located on the side opposite to the side where the capsule endoscope 10 is disposed and does not affect the magnetic field in the region including the capsule endoscope 10. , 222 are arranged so that the external permanent magnet 25a is swiveled without providing a driving member such as the slip ring 306 in the rotating portion, so that the distortion of the magnetic field of the external permanent magnet 25a is suppressed and the slip ring 306 is provided. Compared with the case where a drive member such as the above is provided, the number of parts can be reduced to achieve a reduction in size and weight.

  Further, according to the above-described embodiment, the roll turning mechanism (second turning mechanism) for turning the external permanent magnet 25a is arranged on the yaw turning mechanism (first turning mechanism) for turning the external permanent magnet 25a. Since the differential mechanism is provided, the number of parts can be reduced and the rigidity can be improved as compared with the case where the yaw turning mechanism and the roll turning mechanism are separately provided and stacked.

  Furthermore, according to the above-described embodiment, the rotary motor 221 is located on the side opposite to the side where the capsule endoscope 10 is disposed and does not affect the magnetic field in the region including the capsule endoscope 10. , 222 are arranged, the yaw turning part and the roll turning part can be turned infinitely. Here, if the angle of the turning of the turning unit 210 is restricted, the posture of the capsule endoscope 10 must be controlled by turning in the opposite direction after turning to the limit angle, and continuous posture control can be performed. Disappear. On the other hand, since the permanent magnet turning mechanism according to the present embodiment can turn the external permanent magnet 25a infinitely, the posture can be controlled by continuously controlling the posture with respect to the capsule endoscope 10. Observation processing can be performed.

  In the above-described embodiment, the external permanent magnet 25a rolls with its central axis in the longitudinal direction as a rotation axis (first rotation axis), is orthogonal to the first rotation axis, and is externally permanent. The shaft that passes through the center of the magnet 25a has been described as being yaw-rotated with the rotation axis (second rotation axis) as long as it passes through the vicinity of the center of gravity of the external permanent magnet 25a. Roll rotation may be performed using an axis parallel to the central axis R2 as a first rotation axis, and yaw rotation may be performed using an axis shifted from the center of the external permanent magnet 25a as a second rotation axis. Good.

  In the above-described embodiment, the rotation motors 221 and 222 rotate the gears 221a and 222a to rotate the first turning unit 212 and the second turning unit 213. However, the rotation motors 221 and 222 are provided. Instead, the gears 221a and 222a may be manually rotated by the user.

  As described above, the permanent magnet turning mechanism according to the present invention is useful for improving the operability, suppressing the deterioration of the guidance performance, and realizing downsizing.

DESCRIPTION OF SYMBOLS 1 Capsule type medical device guidance system 10 Capsule type endoscope 11 Imaging part 12 Capsule type housing 13 Illumination part 14 Optical system 15 Imaging element 16 Wireless communication part 17, 26 Control part 18 Power supply part 19 Permanent magnet 20 Guidance device 21 Reception Unit 22 position detection unit 23 display unit 24 operation input unit 25 induction magnetic field generation unit 25a external permanent magnet 25b plane position changing unit 25c vertical position changing unit 25d turning angle changing unit 27 storage unit 110 drive mechanism 120 bed 200 moving unit 201 Z axis Direction moving part 202 X-axis direction moving part 203 Y-axis direction moving part 210, 300 Turning part 211, 301 Base part 212, 302 First turning part 212a, 213a Hollow part 212b, 302a First tooth part 213 Second turning part 213b 2nd tooth part 213c 3rd tooth part 214,215 Holding part 216 Out portion 217 rotating shaft 217a first gear 217b second gear 218 supporting portions 218a, 304 third gear 221,222,303 rotation motor 221a, 222a gears 305 transfer belt 306 slip ring

Claims (4)

Permanent magnet rotation used in a guidance device for guiding the medical device in the subject by introducing a medical device in which the permanent magnet is arranged into the subject and applying a magnetic field to the medical device Mechanism,
An external permanent magnet that applies the magnetic field to the permanent magnet;
A first turning mechanism capable of turning the outer permanent magnet indefinitely around a first rotation axis passing through the vicinity of the center of gravity of the outer permanent magnet and orthogonal to the magnetization direction of the outer permanent magnet;
A second turning mechanism capable of turning the outer permanent magnet indefinitely around the second rotation axis passing through the vicinity of the center of gravity of the outer permanent magnet and orthogonal to the first rotation axis;
A first drive unit that generates rotational power for turning the first turning mechanism;
A second drive unit that generates rotational power for turning the second turning mechanism;
With
The second turning mechanism is disposed on the first turning mechanism, and forms a differential mechanism with the first turning mechanism,
The first and second drive portions are provided on the opposite side of the first and second turning mechanisms along the second rotation axis from the external permanent magnet. Swivel mechanism. Permanent magnet rotation used in a guidance device for guiding the medical device in the subject by introducing a medical device in which the permanent magnet is arranged into the subject and applying a magnetic field to the medical device Mechanism,
An external permanent magnet that applies the magnetic field to the permanent magnet;
The external permanent magnet is pivotably held around a first rotation axis perpendicular to the magnetization direction of the external permanent magnet, and can be pivoted around a second rotation axis perpendicular to the first rotation axis. A first turning unit;
A second swivel portion held by the first swivel portion and capable of swiveling around the second rotation axis independently of the first swivel portion;
Rotational power around the second rotation shaft for turning of the second turning portion is converted into rotation power around the first rotation shaft, and the external permanent magnet is moved to the first rotation shaft. A power converter that turns around,
A first drive unit that generates rotational power for turning the first turning unit;
A second drive unit for generating rotational power for turning the second turning unit;
With
The first and second drive units are provided on the opposite side of the first and second turning units from the external permanent magnet along the second rotation axis. Swivel mechanism.   The permanent magnet turning mechanism according to claim 2, wherein the first and second turning parts and the power conversion part are made of a non-magnetic material. The external permanent magnet has a columnar shape,
The permanent magnet turning mechanism according to any one of claims 1 to 3, wherein the first rotation axis coincides with a central axis in a longitudinal direction of the external permanent magnet.

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