JP2010000210A - Probe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent breaking of a signal cable of a probe. <P>SOLUTION: An ultrasonic vibrator array 18 is rotated around an axis parallel to the insertion axis A of an insertion part. The ultrasonic vibrator array 18 is housed in a tube 33 together with the connected signal cable 23. A flexible shaft 24 is disposed in the outer periphery of the tube 33, and is held by a body cover 32. The signal cable 23 is housed in an internal space 37 of the tube 33, and the flexible shaft 24 is housed in a space 36 separated from the signal cable 23 by the tube 33. A first gear 28 on the driving side and a second gear 29 on the driven side constitute non-contact magnet gears. The first gear 28 is attached to the flexible shaft 24 and the second gear 29 is attached to the signal cable 23. Rotation of the flexible shaft 24 is transmitted to the ultrasonic vibrator array 18 via the first gear 28 and second gear 29. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a probe in which a displaceable probe head is provided at a distal end portion of an insertion portion to be inserted into a subject.

  In the medical field, an ultrasonic examination is known in which a tomographic image in a body cavity is taken by using ultrasonic tomography to observe the inside of a living tissue. There are two types of ultrasonic examinations: an external system that emits ultrasonic waves from the outside of the subject and an internal system that emits ultrasonic waves from inside the body cavity. In the in-body type, an ultrasonic probe having a long insertion portion that is inserted into a body cavity is used. A probe head having an ultrasonic transducer that irradiates the ultrasonic beam and detects the intensity of the reflected wave (reflected echo signal) of the irradiated ultrasonic beam is disposed at the distal end of the insertion unit. At the proximal end, an operation unit is provided for the operator to hold and operate.

  The probe head is composed of, for example, an ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged. The ultrasonic transducer array scans an ultrasonic beam reflected inside a living tissue with a plurality of ultrasonic transducers and detects a reflected echo signal. The ultrasonic transducer array converts the detected reflected echo signal into an electrical signal and outputs it. The electric signal is transmitted to the proximal end side of the insertion portion via a signal cable connected to the ultrasonic transducer array, and is input to a processor device connected to the ultrasonic probe with a cord and a connector. The processor device generates a tomographic image based on the input electrical signal. The direction of the cross section (slice plane) of the tomographic image is parallel to the scanning direction in which the ultrasonic transducer scans the ultrasonic beam.

  Some ultrasonic probes are provided with an ultrasonic transducer array so as to be rotatable within the tip (see Patent Documents 1 to 4). The ultrasonic probes described in Patent Documents 1 to 4 rotate the ultrasonic transducer array so that only the scanning direction of the ultrasonic transducer array changes without changing the irradiation direction of the ultrasonic beam, and tomographic images This is a multi-plane type that changes the orientation of the slice plane. The rotation direction of the ultrasonic transducer array is various. In the ultrasonic probes described in Patent Documents 1 and 2, the ultrasonic transducer array rotates around an axis orthogonal to the insertion axis of the insertion unit. In the ultrasonic probe described in 4, the ultrasonic transducer array rotates around an axis parallel to the insertion axis.

  A driving force for rotating the ultrasonic transducer array is input by a manual operation knob or a motor provided in the operation unit. In the ultrasonic probes described in Patent Documents 1 and 2, a pulley is provided coaxially with the rotation axis of the ultrasonic transducer array. A driving force is transmitted to the pulley by pulling the wire hung on the pulley by operating the operation knob. The wire is disposed in the same space as the signal cable, and extends from the distal end portion of the insertion portion to the proximal end side.

  In the ultrasonic probes described in Patent Documents 3 and 4, a shaft extending in the insertion portion is rotated by a motor, and a driving force is transmitted to the ultrasonic transducer array via the shaft. The shaft is disposed in the same space as the signal cable, like the ultrasonic probes described in Patent Documents 1 and 2.

Further, unlike the ultrasonic probes described in Patent Documents 1 to 4, the ultrasonic probe described in Patent Document 5 has a probe head composed of a single ultrasonic transducer, and the ultrasonic transducer is arranged around the insertion axis. This is a so-called mechanical radial scanning type ultrasonic probe that obtains a tomographic image by irradiating ultrasonic waves radially around the insertion axis. Similar to the ultrasonic probes described in Patent Documents 3 and 4, this ultrasonic probe transmits driving force from the proximal end side of the insertion portion to the probe head in the distal end portion of the insertion portion via the shaft. And the space in which the signal cable is disposed is the same.
JP 2000-201935 A JP-A-6-335481 JP 62-129038 A JP 60-99238 A JP-A-5-92003

  However, when the signal cable and the mechanically movable driving force transmission member such as a wire or a shaft are disposed in the same space as in the ultrasonic probes described in Patent Documents 1 to 5, the driving force transmission member There was a concern that the signal cable would come into contact and the signal cable would break. A probe having an insertion portion to be inserted into a body cavity is particularly problematic because the insertion portion is elongated and the internal space in the duct is narrow, so that the signal cable and the driving force transmission member must be close to each other.

  If the signal cable is broken, not only can the electrical signal not be transmitted, but many of the wires and shafts are made of metal, so there is a danger that the broken part of the signal cable will come into contact with the wire or shaft. There is also a risk of leakage through wires and shafts.

  The present invention has been made in view of the above background, and an object of the present invention is to provide a probe in which a signal cable connected to a probe head is difficult to break.

  In order to solve the above-described problems, a probe of the present invention includes a probe head that is displaceably provided at a distal end portion of an insertion portion that is inserted into a subject, and from the probe head toward a proximal end of the insertion portion. A signal cable that extends and transmits an electrical signal that is input to or output from the probe head; and a first gear on the driving side and a second gear on the driven side that are disposed in the vicinity of the tip. A pair of non-contact type magnet gears that transmit a driving force for displacing the probe head in a non-contact manner by the action of magnetic force, an insertion portion main body that houses the signal cable and the second gear in a tube, The first gear disposed at a position facing the second gear, and a driving force transmission member for transmitting a driving force from the proximal end side of the insertion portion to the first gear are provided on the insertion portion main body. Attached , Characterized in that a holding member for holding the space separated from the inner space of the tube.

  The tube is preferably formed of an insulating material. Moreover, the said holding member is attached to the said insertion part main body so that attachment or detachment is possible, for example. Moreover, it is preferable that the said holding member is a main body cover which covers the outer periphery of the said insertion part main body.

  The driving force transmission member has flexibility so as to bend in accordance with the insertion portion, for example.

  The first gear and the second gear are, for example, ring magnets in which a plurality of magnets are arranged in an annular shape and different magnets are alternately arranged.

  The driving force transmission member is, for example, a rotating member that rotates about an axis parallel to the insertion axis of the insertion portion, and the first gear is provided at an end of the rotation member on the tip end side. . The rotating member is a shaft or a cylindrical member that is rotatably arranged around the outer periphery of the tube. The cylindrical member is preferably provided with the first gear on its inner peripheral surface, and the inner periphery of the first gear and the outer periphery of the second gear are arranged to face each other with the tube interposed therebetween. .

  The second gear is attached to the outer periphery of the signal cable, and the signal cable rotates about its axis as the second gear rotates, and the rotation of the signal cable is directly transmitted to the probe head. It is preferable.

  It is a position in the vicinity of the mounting position of the second gear, and is disposed at a position near the base end of the insertion portion from the mounting position, and the signal cable is fixed, and the signal on the base end side from the fixed position A fixing portion is provided that makes the cable unrotatable and allows only the signal cable on the tip end side to rotate relative to the fixing position, and the signal cable bundles a plurality of signal lines, and the attachment position It is preferable that there is a weak restraint portion between the fixed portion and the fixed portion, the restraint force of the signal line being weak and the torsional resistance being small compared to other portions.

  The probe head includes, for example, an ultrasonic transducer that irradiates an ultrasonic beam for obtaining a tomographic image. The probe head is, for example, an ultrasonic transducer array in which a plurality of the ultrasonic transducers are arranged, and the ultrasonic transducer array rotates around an axis parallel to the insertion axis, The irradiation direction of the sound beam is changed. Here, the axis parallel to the insertion axis includes a rotation axis coinciding with the insertion axis.

  According to the probe of the present invention, the signal cable connected to the probe head and the driving force transmission member are arranged in separate spaces separated by a tube, and the driving force transmission member is utilized using a non-contact type magnet gear. Since the driving force for displacing the probe head from the probe head is transmitted to the probe head, the signal cable and the driving force transmitting member do not come into contact with each other, and the signal cable can be prevented from being disconnected.

  As shown in FIG. 1 and FIG. 2, the ultrasonic probe 10 constitutes an ultrasonic diagnostic apparatus together with a processor device 12 connected via a cord 11. The processor device 12 performs image processing on the electrical signal input from the ultrasonic probe 10 to generate a tomographic image. The generated tomographic image is displayed on the monitor of the processor device 12 and observed.

  The ultrasonic probe 10 includes an insertion portion 13 that is inserted into a body cavity and an operation portion 14 that is connected to the proximal end of the insertion portion 13. In the distal end portion 15 of the insertion portion 13, an ultrasonic transducer array 18 in which a plurality of ultrasonic transducers 16 are arranged on a base portion 17 is provided. The ultrasonic transducer 16 has a strip shape, and the longitudinal direction is arranged in a direction orthogonal to the insertion axis A that coincides with the insertion direction of the insertion portion 13. The ultrasonic transducers 16 are arranged in a line at equal intervals along the insertion axis A. Each ultrasonic transducer 16 is composed of a piezoelectric element including a piezoelectric body and a pair of electrodes sandwiching the piezoelectric body. The ultrasonic transducer 16 emits an ultrasonic wave by applying a pulse voltage between the pair of electrodes, and the intensity of the reflected wave. (Reflected echo signal) is detected and converted into an electrical signal.

  The ultrasonic transducer array 18 is configured so that the ultrasonic transducers 16 are arranged one by one along the arrangement direction, or a group of elements including a predetermined number of ultrasonic transducers 16 is shifted along the arrangement direction. By emitting the sound wave, the ultrasonic beam 19 is irradiated to the site to be observed, and the reflected wave reflected by the site to be observed is scanned by each ultrasonic transducer 16 to detect the reflected echo signal. The processor device 12 generates a tomographic image inside the living tissue of the irradiated region to be observed based on the reflected echo signal converted into the electrical signal. The direction of the cross section (slice plane) of the tomographic image is parallel to the scanning direction. In this example, since the ultrasonic transducers 16 are arranged in a line, the scanning direction and the arrangement direction coincide.

  The ultrasonic transducer array 18 is a convex type in which an irradiation surface that emits ultrasonic waves (an arrangement surface of the ultrasonic transducers 16) is curved in a convex shape, and an ultrasonic beam 19 having a wavefront corresponding to the shape of the irradiation surface. Irradiate. The shape of the tomographic image is a shape corresponding to the shape of the ultrasonic beam 19, and in the case of a convex type, it is a sector shape.

  In the distal end portion 15, the ultrasonic transducer array 18 is arranged so that the scanning direction is parallel to the insertion axis A, and is provided to be rotatable around a rotation axis parallel to the insertion axis A. The ultrasonic transducer array 18 can be rotated at an arbitrary angle within a range of about 180 ° in each of the forward and reverse directions and a total of about 360 ° in both directions with reference to the initial position with the irradiation surface facing upward in FIG. It is. Thereby, the ultrasonic beam 19 can be irradiated radially around the rotation axis according to the rotation angle of the ultrasonic transducer array 18.

  Since the ultrasonic transducer array 18 rotates in a state where the scanning direction and the rotation axis are kept parallel, even if the irradiation direction of the ultrasonic transducer array 18 changes according to the rotation, the cross section of the tomographic image (slice plane) ) Is always parallel to the axis of rotation. By rotating the ultrasonic transducer array 18 in this manner, for example, the ultrasonic beam 19 is irradiated to the entire circumference of the inner wall of the duct in the body cavity, and a tomographic image inside the living tissue on the inner wall is obtained over the entire circumference. It becomes possible to observe.

  The ultrasonic probe 10 is inserted into the body cavity through the forceps channel of the endoscope 21. As is well known, the endoscope 21 irradiates illumination light from an illumination window 21a disposed at the distal end of the insertion portion of the endoscope 21, and reflects the reflected light by an imaging device disposed behind the observation window 21b. An endoscopic image is obtained by receiving light. The forceps channel is a channel through which a treatment tool such as forceps is inserted, and communicates with the forceps outlet 21c at the tip. The insertion portion 13 of the ultrasonic probe 10 is inserted into a forceps channel from a forceps port (not shown) arranged on the proximal end side of the insertion portion of the endoscope 21, and the distal end portion 15 projects from the forceps outlet 21c.

  The insertion portion 13 of the ultrasonic probe 10 has flexibility, and a driving force for rotating the signal transducer 23 for transmitting an electrical signal and the ultrasonic transducer array 18 is provided inside the insertion portion 13. Is provided with a flexible shaft (driving force transmission member) 24. The signal cable 23 transmits a reflected echo signal output from the ultrasonic transducer array 18 and a drive signal input to the ultrasonic transducer array 18.

  The longitudinal direction of the flexible shaft 24 is arranged along the insertion axis A. As is well known, the flexible shaft 24 is obtained by winding a wire-shaped steel wire around a long core wire, and bends in accordance with the curvature of the insertion portion 13.

  The flexible shaft 24 is exposed to the outside from the insertion portion 13 before the operation portion 14, and an operation knob 26 is provided at the exposed end portion. The operation knob 26 is operated by an operator and inputs a driving force for rotating the ultrasonic transducer array 18 to the flexible shaft 24. When the operation knob 26 rotates, the flexible shaft 24 rotates about its axis, and the driving force is transmitted to the ultrasonic transducer array 18 via the magnet gear (magnetic gear) 27 and the signal cable 23.

  As will be described in detail later, the magnet gear 27 is a pair of gears composed of a first gear 28 on the driving side and a second gear 29 on the driven side. A driving force is transmitted to the gear 29. The first gear 28 is attached to the flexible shaft 24, and the second gear 29 is attached to the signal cable 23.

  The signal cable 23 connects the ultrasonic transducer array 18 and the processor device 12 via the cord 11, and connects a plurality of signal lines 23 a (see FIG. 3) that connect to each of the plurality of ultrasonic transducers 16. It is a bundle. The plurality of signal lines 23a are restrained by a covering material or a bind line so as not to be separated.

  The insertion portion 13 includes an insertion portion main body 31 and a main body cover 32 that covers the outer periphery of the insertion portion main body 31. The insertion portion main body 31 includes an ultrasonic transducer array 18 and a signal cable 23, and a tube 33 for housing them in a watertight manner.

  The main body cover 32 is composed of two separable cover portions 34 and 35 having a cut surface along the longitudinal direction of the insertion portion 13, and the insertion portion main body 31 except for the distal end portion 15 of the insertion portion main body 31. Cover the outer periphery of. The cover portions 34 and 35 are made of, for example, a hard resin compared to the tube 33. Since the tube 33 needs to efficiently transmit the ultrasonic waves generated by the ultrasonic transducer array 18, the peripheral wall of the tube 33 is thin and the rigidity is low. By forming the main body cover 32 from a hard resin and covering the tube 33 with the main body cover 32, the rigidity of the insertion portion main body 31 is complemented, and the necessary rigidity of the insertion portion 13 as a whole is ensured.

  As shown in FIG. 4, the cover portions 34 and 35 are formed with an engaging protrusion 34a and an engaging groove 35a for engaging both. The engagement protrusion 34a has a spherical engagement portion with a narrow root and a diameter larger than the root at the tip, and the engagement groove 35a has a cross-sectional shape corresponding to the cross-sectional shape of the engagement protrusion 34a. The cover portions 34 and 35 are detachably combined by pushing the engagement protrusion 34a into the engagement groove 35a while elastically deforming the engagement protrusion 34a and the engagement groove 35a, and engaging the both. Thereby, the main body cover 32 is attached to the insertion portion main body 31. When removing the main body cover 32 from the insertion portion main body 31, the engagement between the engagement protrusion 34a and the engagement groove 35a is released, and the cover portions 34 and 35 are separated.

  In FIG. 3, the tube 33 has an insulating property and is formed of a flexible resin material, and electrically insulates the inside of the tube 33 from the subject. The distal end portion of the tube 33 constitutes the distal end portion 15 of the insertion portion 13 that accommodates the ultrasonic transducer array 18. The tip portion 15 is formed in a bag shape. The distal end portion 15 has a larger diameter than the middle portion 33a that accommodates the signal cable 23, and a cross-sectional shape parallel to the insertion axis A is formed in a substantially egg shape. The ultrasonic transducer array 18 is rotatably accommodated inside the tube 33, and the tube 33 itself does not rotate. Since the ultrasonic transducer array 18 is a convex type, the irradiation surface is curved in a convex shape, so that the distal end portion 15 is formed in a substantially egg shape in order to secure the rotation space.

  For example, when the ultrasonic probe 10 is assembled, the tube 33 is separated into two parts, that is, the distal end portion 15 and the middle path portion 33a. The acoustic wave transducer array 18 is accommodated, and the signal cable 23 is accommodated in the midway portion 33a, and then the distal end portion 15 and the midway portion 33a are welded.

  The flexible shaft 24 is disposed on the outer periphery of the middle portion 33 a of the tube 33 together with the first gear 28 and is rotatably held by the main body cover 32. The cover portion 34 is formed with an accommodation groove for forming a space 36 in which the flexible shaft 24 and the first gear 28 are accommodated. The space 36 is separated from the internal space 37 of the tube 33 by the peripheral wall of the middle part 33 a of the tube 33.

  Unlike the cover part 35, the cover part 34 has a substantially oval shape in which a section where the accommodation groove is formed is expanded (see FIG. 4). A bearing 34 b that supports the flexible shaft 24 is provided on the inner wall of the housing groove. The bearing 34b is formed integrally with the cover portion 34, and is formed with a slit (not shown) extending in the axial direction of the flexible shaft 24 on the convex portion protruding from the inner wall of the housing groove. The slit has a narrow cross-section and a narrow entrance, and the back is formed in a circular shape to hold the flexible shaft 24 rotatably. The flexible shaft 24 is attached to the bearing 34b by opening the slit while elastically deforming the bearing 34b and being pushed into the slit.

  A positioning ring 38 is attached to the flexible shaft 24 so as to abut the side end surface of the bearing 34b and regulate the position of the flexible shaft 24 in the axial direction. Further, the cover portion 34 is formed with a concave portion 34 c that fits with the end portion on the distal end portion 15 side of the flexible shaft 24 and supports the flexible shaft 24. The flexible shaft 24 is positioned in a direction orthogonal to the rotation axis by the recess 34c.

  A stopper 39 having substantially the same shape as the positioning ring 38 is provided on the proximal end side of the flexible shaft 24. The stopper 39 abuts against the inner wall of the rear end portion of the cover portion 34 to restrict the position of the flexible shaft 24 in the axial direction and functions as a retaining member that prevents the flexible shaft 24 from coming out of the cover portion 34. .

  The first gear 28 is fixed to the end of the flexible shaft 24 on the tip 15 side, and rotates with the rotation of the flexible shaft 24. The second gear 29 is accommodated in the internal space 37 of the tube 33. The first gear 28 and the second gear 29 are disposed at positions facing each other across the peripheral wall of the middle path portion 33 a of the tube 33. The second gear 29 is fixed to the signal cable 23. When the second gear 29 rotates, the signal cable 23 also rotates about the axis, and the rotation is directly transmitted to the ultrasonic transducer array 18.

  When the signal cable 23 is rotated, there is a limit to the amount of twist of the signal cable 23. Therefore, as described above, the rotation range of the second gear 29 and the ultrasonic transducer array 18 is determined in the forward and reverse directions with respect to the initial position. The angle is regulated to about 360 ° in total in both directions by about 180 °. Of course, the value of this rotation range is not limited to this example. For example, the total signal cable 23 is 210 ° in each forward and reverse direction, a total of 420 °, or 150 ° in each forward and reverse direction, and a total of 300 °. It is set as appropriate according to the limit of the twist amount.

  Further, the signal cable 23 is also used as a component constituting a driving force transmission mechanism for the ultrasonic transducer array 18, so that a dedicated component constituting the driving force transmission mechanism is used separately from the signal cable 23. Thus, the merit that the structure of the insertion portion main body 31 can be simplified is also obtained. Further, the diameter of the tube 33 can be reduced by reducing the number of parts accommodated in the internal space 37 of the tube 33.

  The signal cable 23 is connected to the base portion 17 of the ultrasonic transducer array 18, and the connecting portion 40 between the base portion 17 and the signal cable 23 is coated with a curing agent so that the signal cable 23 does not bend. It is hardened by application. For this reason, the rotational force of the signal cable 23 is efficiently transmitted to the ultrasonic transducer array 18. In addition to hardening with a curing agent, the connecting portion 40 may be reinforced by attaching a rigid body.

  As shown in FIG. 4, the first gear 28 and the second gear 29 are ring magnets in which a plurality of magnets 41 and 42 are arranged in an annular shape, respectively. The magnets 41 and 42 have different magnetic poles (N and S) arranged alternately. The first gear 28 and the second gear 29 are arranged so that their outer peripheral surfaces face each other and the magnets 41 and 42 face each other.

  Transmission of driving force from the first gear 28 to the second gear 29 is performed through repulsive force generated when the same poles of the magnets 41 and 42 approach each other and attraction force generated when the opposite poles approach each other. . For example, when the south pole of the magnet 41 of the first gear 28 and the north pole of the magnet 42 of the second gear 29 are opposed to each other, an attractive force is generated between the magnets 41 and 42. When the first gear 28 rotates clockwise, the N pole of the magnet 41 approaches the N pole of the magnet 42 of the second gear 29, so that repulsive force is generated and the second gear 29 rotates counterclockwise. More detailed contents of such a non-contact type magnet gear (magnetic gear) are disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2007-244014, 2007-239765, and 2007-010157.

  The number of magnets 41 and 42 of each of the first gear 28 and the second gear 29 corresponds to the number of teeth of a normal gear that physically contacts and meshes. The first gear 28 includes four magnets 41, and the second gear 29 includes eight magnets 42. Therefore, the reduction ratio (the number of teeth on the driven side / the number of teeth on the driving side) of the first gear 28 and the second gear 29 is “2”, and when the first gear 28 rotates twice, the second gear 29 rotates once. To do.

  Further, since the rotation of the second gear 29 is directly transmitted to the ultrasonic transducer array 18 via the signal cable 23, the minimum number of the ultrasonic transducer array 18 depends on the number of teeth of the second gear 29 (the number of magnets 42). The rotation angle is determined. The minimum rotation angle is larger as the number of teeth of the second gear 29 is smaller, and the minimum rotation angle is smaller as the number is larger. The smaller the minimum rotation angle, the finer angle adjustment of the ultrasonic transducer array 18 is possible. The reduction ratio and the number of teeth of the second gear 29 are appropriately selected in consideration of the outer diameters of the first gear 28 and the second gear 29, the required driving force, and the like.

  Reference numeral 44 is a cylindrical pipe serving as a base for attaching the second gear 29 to the signal cable 23. As shown in FIGS. 2 and 3, the pipe 44 has a convex portion 44 a formed on the outer periphery of the end portion on the tip side. The convex portion 44 a is a stopper that regulates the rotation range of the signal cable 23. The convex portion 44 a contacts the convex portion 33 b formed on the inner wall of the tube 33 when the second gear 29 rotates in the forward direction or the reverse direction from the initial position and the convex portion 44 a rotates about 180 °. This contact restricts the rotation range of the signal cable 23 and the ultrasonic transducer array 18. Further, the convex portion 33 b abuts on the side end surface of the second gear 29 and functions as an axial positioning member within the tube 33 of the second gear 29 and the ultrasonic transducer array 18.

  Further, the convex portion 33c rotates the tube 33 so that the tube 33 is not rotated by friction with the inner wall of the tube 33 when the second gear 29, the signal cable 23 and the ultrasonic transducer array 18 rotate. It is a stopper that regulates. The convex portion 33 c is formed so as to protrude from the outer periphery of the tube 33, and engages with a concave portion formed on the inner wall of the cover portion 35 to restrict the rotation of the tube 33. In FIG. 3, only one convex portion 33c is shown, but a plurality of convex portions 33c and corresponding concave portions are provided at important points.

  The attachment position of the second gear 29 is in the vicinity of the connection portion 40 between the signal cable 23 and the ultrasonic transducer array 18. As described above, since the connection portion 40 is cured by the curing agent, the signal cable 23 is less twisted between the second gear 29 and the ultrasonic transducer array 18. However, the twist of the signal cable 23 can be further reduced by narrowing the distance between the second gear 29 and the ultrasonic transducer array 18. Since the twisting of the signal cable 23 causes a transmission loss of the driving force, the transmission loss can be suppressed by reducing the twist.

  Further, the signal cable 23 is fixed to the tube 33 by, for example, a fixing portion 46 in the vicinity of the attachment position of the second gear 29 and at a position from the attachment position to the proximal end of the insertion portion 13. The fixing part 46 is constituted by, for example, a cylindrical bearing member into which the signal cable 23 can be inserted. The inner peripheral surface of the fixing portion 46 is fixed to the outer peripheral surface of the signal cable 23. And the outer periphery of the fixing | fixed part 46 and the inner wall of the tube 33 are adhere | attached with an adhesive agent, and the signal cable 23 and the tube 33 are fixed.

  The signal cable 23 is rotated by the rotation of the second gear 29, but the portion of the signal cable 23 on the base end side with respect to the fixing portion 46 is not rotated by the fixing portion 46, and therefore does not rotate. For this reason, the transmission loss of the operation force input from the operation knob 26 through the flexible shaft 24 is reduced. That is, by rotating only the portion on the distal end portion 15 side from the fixed portion 46 in the entire length of the signal cable 23, the weight of the rotating portion of the signal cable 23, the friction with the inner wall of the tube 33, the torsional resistance of the signal cable 23 Thus, since the rotational load of the signal cable 23 is reduced, the transmission loss of the operating force is reduced. Since there is little transmission loss, the operation force of the operation knob 26 can be reduced, so that it is easy to operate.

  In addition, the signal cable 23 has a weak restraint portion 47 between the mounting position of the second gear 29 and the fixed portion 46, and the restraint force of the signal lines 23a is weaker than that of other portions. The weak restraint portion 47 is formed, for example, by removing the covering material of the signal cable 23 that covers and restrains the plurality of signal lines 23a and gives the exposed signal lines 23a slack.

  In FIG. 3, in order to show the accommodation state of the signal line 23 a in the portion other than the weak restraint portion 47, the covering material of the signal cable 23 is partially broken at the attachment position of the second gear 29. As can be seen from this figure, in the portions other than the weak restraint portion 47, the signal line 23a is strongly restrained by the covering material and is neatly accommodated so that no gap is formed between the signal lines 23a. For this reason, since the deformation and movement of the signal line 23a are restricted, the torsional resistance of the signal cable 23 is large.

  On the other hand, in the weak restraint part 47, since the covering material is removed to loosen the signal line 23a, a gap is generated between the signal lines 23a. For this reason, in the weak restraint part 47, the freedom degree of a deformation | transformation and movement of the signal wire | line 23a is high, and torsional resistance reduces. When the torsional resistance of the signal cable 23 decreases, the rotational load decreases and the operating force of the operation knob 26 is reduced.

  Note that the method of making the weak restraint portion 47 is not limited to the method of removing the covering material. For example, when the important part of the signal line 23a is constrained by the bind line, the part of the part to be restrained with the bind line is made wider than the other part, and the signal line 23a is loosened. Give it.

  Hereinafter, the operation of the above configuration will be described. When performing an ultrasonic examination, the operator inserts the endoscope 21 into the body cavity of the subject and causes the insertion portion of the endoscope 21 to reach the site to be observed. In this state, the insertion portion 13 of the ultrasonic probe 10 is inserted from the forceps opening of the endoscope 21, and the distal end portion 15 is protruded from the forceps outlet 21c. The ultrasonic transducer array 18 operates when a drive signal is input from the processor device 12 through the signal cable 23.

  The ultrasonic transducer array 18 irradiates the ultrasonic beam 19, detects the reflected echo signal, converts it into an electrical signal, and outputs it to the signal cable 23. The electric signal is transmitted through the signal cable 23 and input to the processor device 12 through the cord 11. The processor device 12 generates a tomographic image based on the input electrical signal and displays it on the monitor. The surgeon observes the tomographic image and examines the state of the affected part or lesion.

  When the operation knob 26 is rotated, the flexible shaft 24 rotates and the first gear 28 rotates. When the first gear 28 rotates, the second gear 29 that faces the tube 33 through the action of the magnetic force rotates. When the second gear 29 rotates, the signal cable 23 rotates, and the ultrasonic transducer array 18 connected thereto rotates around the insertion axis A. Thereby, the irradiation direction of the ultrasonic beam 19 changes, and the observation direction can be changed.

  Since the flexible shaft 24 is provided in a space 36 separated from the internal space 37 in which the signal cable 23 is accommodated by using the tube 33 as a partition, the rotating flexible shaft 24 and the signal cable 23 do not come into contact with each other. As compared with the conventional case where the signal cable and the driving force transmission member such as a wire and a shaft are arranged in the same space, the risk of disconnection of the signal cable 23 is reduced. In addition, since the tube 33 is formed of an insulating material, there is no risk of a short circuit between the broken wire of the signal cable 23 and a metal such as a wire or a shaft. Furthermore, since the signal cable 33 is accommodated in the tube 33, even if the signal cable 23 is disconnected, there is no leakage into the living body, and the electrical safety is high.

  When the ultrasonic examination is completed and the ultrasonic probe 10 is removed from the body cavity, the ultrasonic probe 10 is washed. At the time of cleaning, the used ultrasonic probe 10 separates the cover portions 34 and 35, and the main body cover 32 is removed from the insertion portion main body 31. Since the insertion portion main body 31 is covered by the main body cover 32 except for the distal end portion 15, there are few places to which dirt adheres and it is easy to clean.

  Further, since the main body cover 32 and the insertion portion main body 31 are detachable, the following effects can be obtained. 1stly, since the insertion part main body 31 and the main body cover 32 differ in a component, respectively, a lifetime is also different. If both of them are detachable, it is possible to replace only a part whose lifetime has passed or a part whose deterioration has progressed, and the maintenance cost of the user can be suppressed.

  Secondly, for example, when different types of insertion portion main bodies 31 having different types of ultrasonic transducer arrays 18 are used, only the insertion portion main body 31 is replaced, and one main body cover 32 is replaced with a plurality of types of insertion portion main bodies 31. It can be shared by the insertion portion main body 31. Examples of the plurality of types of insertion portion main bodies 31 include those having different performance such as the resolution of the ultrasonic transducer array and those having different types of the ultrasonic transducer array. The types of the ultrasonic transducer array include a linear type in which an irradiation surface is flat and an ultrasonic beam is scanned linearly, an arc type in which an arc is scanned.

  In the first embodiment, an example in which the housing groove is formed in the main body cover 32 and the flexible shaft 24 is housed in the housing groove has been described. However, when the peripheral wall of the main body cover 32 is thick, instead of the groove. An insertion hole may be formed, and the flexible shaft 24 may be accommodated in the insertion hole. In this case, in addition to the peripheral wall of the tube 32, a part of the main body cover 32 is interposed between the space 36 in which the flexible shaft 24 is accommodated and the internal space 37 of the tube 32.

  In the first embodiment, the main body cover has been described with an example in which the main body cover is configured by two separable members (cover portions 34 and 35). However, the main body cover is configured by a single member as in the main body cover 51 shown in FIG. May be. The main body cover 51 is provided with a cut 51a along the longitudinal direction (parallel to the insertion axis A). The cut 51a is for attaching and detaching the flexible shaft 24 and the insertion portion main body 31. At the time of attachment / detachment, the notch 51a is widened by elastically deforming the main body cover 51 as indicated by a two-dot chain line.

  In this case, as shown in FIG. 6, the band 52 may be attached to the main body cover 51 to restrain the main body cover 51 from the outer periphery. The band 52 prevents the cutout 51 a of the main body cover 51 from being inadvertently opened, causing the flexible shaft 24 and the insertion portion main body 31 to be displaced within the main body cover 51 or falling off the main body cover 51.

  In the first embodiment, the driving force is input to the flexible shaft 24 by manual operation (rotating operation of the operation knob 26). However, the motor 56 drives the flexible shaft 24 as shown in FIG. You may rotate by inputting force. For example, the motor 56 is provided in the operation unit 14. The operation unit 14 is provided with an operation button 57 for instructing on / off of the motor 56 and its rotation direction.

  A second embodiment of the present invention will be described with reference to FIGS. The main difference between the ultrasonic probe 60 shown in FIG. 8 and the ultrasonic probe 10 of the first embodiment is the form of a non-contact type magnet gear. Hereinafter, the differences will be mainly described, and common portions and components are denoted by the same reference numerals as those in the first embodiment, and description thereof will be omitted.

  The non-contact type magnet gear 61 of the ultrasonic probe 60 is composed of a first gear 62 on the driving side and a second gear 63 on the driven side, and is composed of a set of ring magnets as in the first embodiment. The second gear 63 is common to the second gear 29 of the first embodiment. The first gear 62 has an inner diameter that is larger than the outer diameter of the second gear 63. The inner peripheral surface of the first gear 62 and the outer peripheral surface of the second gear 63 face each other with the tube 72 interposed therebetween, and the first gear 62 and the second gear 63 rotate on the same axis.

  The first gears 62 and 63 have the same number (eight) of magnets 66 and 67. Each magnet 66 of the first gear 62 is disposed to face each magnet 67 of the second gear 63. Therefore, a large driving force can be obtained between the first gear 62 and the second gear 63 as compared with the first embodiment in which only one magnet is opposed.

  The first gear 62 is fixed to the inner peripheral surface of the cylindrical member 71. The cylindrical member 71 is a driving force transmission member having the same function as the flexible shaft 24 of the first embodiment. The cylindrical member 71 has flexibility, is long along the direction of the insertion axis A, and has an inner diameter that accommodates the tube 72. The cylindrical member 71 is provided with an operation knob 73 at the end on the proximal end side of the insertion portion 13. When the operation knob 73 is rotated, the cylindrical member 71 is rotated and the first gear 62 is rotated. As a result, the ultrasonic transducer array 18 rotates through the second gear 63 and the signal cable 23. The cylindrical member 71 is rotatably held on the outer periphery of the tube 72 by the main body cover 76.

  The main body cover 76 includes three separable members including cover portions 77 and 78 and a cap 79. The cover portions 77 and 78 include the same engagement portions as the engagement protrusions 34 a and the engagement grooves 35 a of the cover portions 34 and 35 of the first embodiment, and are detachably attached to the insertion portion main body 31.

  The cover portion 78 is formed with a concave portion that engages with the convex portion 72 a of the tube 72. The convex portion 72 a corresponds to the convex portion 33 c of the first embodiment, and is a stopper that restricts the rotation of the tube 72. Further, the convex portion 72 b of the tube 72 corresponds to the convex portion 33 b of the first embodiment, and is a stopper that contacts the convex portion 44 a of the pipe 44 and restricts the rotation range of the ultrasonic transducer array 18.

  Engaging grooves 77 a and 78 a that engage with convex portions 71 a formed on the outer periphery of the cylindrical member 71 are formed on the inner peripheral surfaces of the cover portions 77 and 78. The position of the cylindrical member 71 in the axial direction is restricted by the engagement between the convex portion 71a and the engaging grooves 77a and 78a. Reference numeral 71 b is a convex portion for ensuring a clearance between the inner peripheral surface of the cylindrical member 71 and the inner peripheral surface of the tube 72. Further, the end of the cylindrical member 71 on the front end side is fitted and supported by grooves 77b and 78b formed in the cover portions 77 and 78. The position of the cylindrical member 71 in the direction orthogonal to the axial direction of the cylindrical member 71 is determined by the grooves 77b and 78b and the convex portion 71b.

  When assembling the ultrasonic probe 60, first, the ultrasonic transducer array 18 and the signal cable 23 are connected to the tube 72 by the same method as in the first embodiment (after accommodating the built-in material, the distal end portion and the middle portion of the road are welded). Store watertight. Next, the cylindrical member 71 is inserted and attached from the rear end side of the tube 72. Since the operation unit 14 becomes an obstacle when the cylindrical member 71 is attached, it is preferable that the signal cable 23 and the operation unit 14 be detachable with a connector.

  After attaching the cylindrical member 71, the cover parts 77 and 78 are attached so as to cover the outer periphery of the cylindrical member 71. After the cover portions 77 and 78 are attached, the cap 79 is attached from behind the operation knob 73. After the cap 79 is attached, the signal cable 23 and the operation unit 14 are connected. Thus, the ultrasonic probe 60 is assembled.

  In the above embodiment, an example in which only the ultrasonic transducer array accommodated in the tube is rotated without rotating the tube has been described. However, the ultrasonic transducer array may be rotated for each tube. Moreover, although the example which accommodated the ultrasonic transducer | vibrator array, the signal cable, and the 2nd gear in one tube was demonstrated, the signal cable and the 2nd gear should just be accommodated in the tube. When the ultrasonic transducer array is not accommodated in the tube, another tube is covered, or a cover that covers the ultrasonic transducer array in a watertight manner is provided instead of the tube. The cover may be in close contact with the outer peripheral surface of the ultrasonic transducer array. Further, if the ultrasonic transducer array itself has a watertight structure, a cover is not necessary.

  In the above-described embodiment, the ultrasonic transducer array is rotated around a rotation axis parallel to the scanning direction, and the rotation changes the irradiation direction of the ultrasonic beam irradiated radially with respect to the rotation axis. Although described by way of example, the present invention is not limited to the above embodiment. For example, the present invention can be applied to a multi-plane type ultrasonic probe 81 as shown in FIG. In the multi-plane type ultrasonic probe, unlike the above embodiment, even if the ultrasonic transducer array rotates, the irradiation direction of the ultrasonic beam does not change, and only the scanning direction rotates. Thereby, the direction of the cross section (slice plane) of the tomographic image can be changed.

  The ultrasonic probe 81 is attached with an ultrasonic transducer array 82 such that the irradiation direction of the ultrasonic beam 19 faces the front of the tip and the irradiation direction is parallel to the insertion axis A. This is a multi-plane type in which 82 is rotated around a rotation axis parallel to the insertion axis A and the scanning direction by the ultrasonic transducer 83 is rotated.

  In addition, the ultrasonic beam irradiation direction is orthogonal to the insertion axis A, as in the ultrasonic probe described in Japanese Patent Application Laid-Open No. 2000-201935 and Japanese Patent Application Laid-Open No. The present invention may be applied to a general multi-plane type ultrasonic probe that rotates around the rotation axis orthogonal to the insertion axis A and changes the scanning direction without changing the irradiation direction. In this case, the rotational force of the second gear transmitted from the first gear may be transmitted to the ultrasonic transducer array with the rotating shaft bent using a bevel gear or the like.

  Furthermore, it is not limited to rotating the ultrasonic transducer array, and may be moved linearly. In this case, for example, the rotary motion is converted into a linear motion using the worm gear and the worm wheel type non-contact type magnet gear described in JP 2007-239765 A, or transmitted by the magnet gear. Rotational force is converted into linear motion by rack and pinion method. Moreover, although the said embodiment demonstrated in the example which used 1 set of non-contact-type magnet gears, you may use two or more sets.

  In the above embodiment, the example in which the main body cover is used as the holding member that holds the driving force transmission member on the outer periphery of the insertion portion main body has been described. However, the holding member may not be the main body cover, and the outer periphery of the insertion portion main body. Any member that can hold the driving force transmission member on the surface may be attached to a part of the outer peripheral surface of the insertion portion main body, for example. Further, the holding member may not be detachable and may be fixedly attached to the insertion portion main body.

  In the above embodiment, the example in which the rotating member such as the shaft or the cylindrical member is used as the driving force transmitting member has been described. For example, a wire and a pulley on which the wire is hung may be disposed in the housing groove of the main body cover, the pulley may be rotated by pulling the wire, and the first gear may be driven by the rotational force.

  In the above embodiment, the ultrasonic probe inserted into the subject through the forceps channel of the endoscope has been described as an example. However, an ultrasonic transducer together with the imaging element is provided at the distal end of the insertion portion of the endoscope. You may apply this invention to the ultrasonic probe (ultrasonic endoscope) incorporated integrally.

  In the above-described embodiment, the flexible type ultrasonic probe having a flexible insertion portion has been described as an example. However, like the ultrasonic probe described in Japanese Patent Application Laid-Open No. Sho 62-129038 shown as the prior art, The present invention may be applied to a rigid ultrasonic probe that does not have flexibility.

  In the above embodiment, the ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged is described as an example of the probe head of the present invention. However, the ultrasonic transducer described in Japanese Patent Laid-Open No. 5-92003 shown as the prior art is described. The present invention may be applied to an ultrasonic probe having a mechanical radial probe head that rotates a single ultrasonic transducer, such as an acoustic probe.

  The present invention is not limited to a probe head having an ultrasonic transducer, but may be applied to a probe head of an OCT (optical coherence tomography) probe that obtains a tomographic image inside a living tissue using low coherent light.

  The present invention is not limited to a medical probe, and may be applied to an industrial probe used for inspection of piping and the like. Further, the present invention is not limited to a probe that obtains a tomographic image, but may be applied to a probe for obtaining information other than a tomographic image, for example, various information in the subject such as temperature, humidity, and gas leakage in the subject. .

It is an external view of an ultrasonic probe. It is a disassembled perspective view of the insertion part of an ultrasonic probe. It is sectional drawing of an insertion part. It is explanatory drawing of a non-contact-type magnet gear. It is explanatory drawing of the main body cover comprised by 1 components. It is explanatory drawing of the band which fastens the main body cover of FIG. It is explanatory drawing of a motor drive ultrasonic probe. It is sectional drawing of the ultrasonic probe of 2nd Embodiment. It is explanatory drawing of the non-contact-type magnet gear of the ultrasonic probe of FIG. It is explanatory drawing of a multi-plane type ultrasonic probe.

Explanation of symbols

10, 60, 81 Ultrasonic probe 13 Insertion section 15 Tip section 16, 83 Ultrasonic transducer 18, 82 Ultrasonic transducer array 23 Signal cable 24 Flexible shaft 27, 61 Magnet gear 28, 62 First gear 29, 63 First 2 gear 31 insert part main body 32, 51, 76 main body cover 33, 72 tube 34, 35, 77, 78 cover part 36 space 37 internal space 41, 42, 66, 67 magnet 40 connection part 46 fixing part 47 weak restraint part 56 Motor 71 Cylindrical member

Claims (14)

A probe head that is slidably provided at a distal end portion of an insertion portion to be inserted into a subject;
A signal cable that extends from the probe head toward the proximal end of the insertion portion and transmits an electrical signal that is input to or output from the probe head;
A pair of a first gear on the driving side and a second gear on the driven side that are disposed in the vicinity of the tip portion, and transmits a driving force for displacing the probe head in a non-contact manner by the action of magnetic force. Non-contact type magnet gear,
An insertion portion main body containing the signal cable and the second gear in a tube;
The first gear disposed at a position facing the second gear, and a driving force transmission member for transmitting a driving force from the proximal end side of the insertion portion to the first gear are provided on the insertion portion main body. A probe comprising a holding member attached and held in a space separated from the internal space of the tube.   The probe according to claim 1, wherein the tube is made of an insulating material.   The probe according to claim 1, wherein the holding member is detachably attached to the insertion portion main body.   The probe according to claim 1, wherein the holding member is a main body cover that covers an outer periphery of the insertion portion main body.   The probe according to any one of claims 1 to 4, wherein the driving force transmission member has flexibility so as to bend in accordance with the insertion portion.   The probe according to any one of claims 1 to 5, wherein the first gear and the second gear are ring magnets in which a plurality of magnets are arranged in an annular shape and different magnetic poles are alternately arranged.   The driving force transmission member is a rotating member that rotates about an axis parallel to the insertion axis of the insertion portion, and the first gear is provided at an end portion of the rotation member from the distal end portion. The probe according to any one of claims 1 to 6, characterized in that:   The probe according to claim 7, wherein the rotating member is a shaft. The rotating member is a cylindrical member that is rotatably arranged around the outer periphery of the tube.
The first gear is provided on an inner peripheral surface of the cylindrical member;
The probe according to claim 7, wherein an inner periphery of the first gear and an outer periphery of the second gear are arranged to face each other with the tube interposed therebetween.   The second gear is attached to the outer periphery of the signal cable, and the signal cable rotates about its axis as the second gear rotates, and the rotation of the signal cable is directly transmitted to the probe head. The probe according to any one of claims 1 to 9, wherein:   The probe according to claim 10, wherein the mounting position of the second gear is a position in the vicinity of a connection portion between the probe head and the signal cable. It is a position in the vicinity of the mounting position of the second gear and is disposed at a position near the base end of the insertion portion from the mounting position, and the signal cable is fixed, and the signal on the base end side with respect to the fixed position A fixing portion is provided that makes the cable unrotatable and allows only the signal cable on the tip end side to be rotated from the fixing position.
The signal cable bundles a plurality of signal wires, and has a weak restraint portion between the mounting position and the fixing portion, which has a weak restraining force of the signal line and a small torsional resistance compared to other portions. The probe according to claim 11, wherein   The probe according to claim 1, wherein the probe head includes an ultrasonic transducer that irradiates an ultrasonic beam for obtaining a tomographic image. The probe head is an ultrasonic transducer array in which a plurality of the ultrasonic transducers are arranged,
The probe according to claim 13, wherein the ultrasonic transducer array rotates around an axis parallel to the insertion axis to change the irradiation direction of the ultrasonic beam.

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