JP2007289315A - Ultrasonic probe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable ultrasonic probe capable of reducing a friction load and stably swinging an ultrasonic transducer assembly 1 for a long period of time. <P>SOLUTION: A component constituting a sealing means for sealing an acoustic transmission medium is so constituted as to have no sliding part when swinging the ultrasonic transducer assembly 1. A driving means is constituted of a pair of a coil 6a integrally formed with an arm and having its axial direction perpendicular to the swinging face and a magnet 6b integrated therewith; and a back yoke 6c so as to minimize the apparatus. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic probe, for example, an ultrasonic probe used in an ultrasonic diagnostic apparatus that obtains an image in a subject using ultrasonic waves.

  Medical ultrasound capable of constructing an arbitrary tomographic image or stereoscopic image by electronic scanning in the arrangement direction of the ultrasonic transducers and mechanical scanning that moves or swings in a direction orthogonal to the electronic scanning direction A probe is known.

  FIG. 6 is a perspective view showing the configuration of the main part of the above-described conventional ultrasonic probe. In FIG. 6, an ultrasonic transducer assembly 101 including a plurality of arranged ultrasonic transducers (not shown) is integrally assembled with an arm 103, and a swing shaft 104 is attached to the arm 103. Are integrally connected at both ends. The swing shaft 104 is rotatably supported by a bearing 105 assembled to the base 109, and further, a first pulley 120, a belt 121, and a second pulley 122 assembled integrally to the swing shaft 104. Is engaged with the drive motor output shaft 124 of the drive motor 123. Transmission / reception of electrical signals to / from the ultrasonic transducer assembly 101 is performed via the connection member 102. The acoustic window 108 has a bell shape and is disposed so as to cover the outside of the ultrasonic transducer assembly 101, and a liquid acoustic transmission medium is sealed inside the acoustic window 108. Further, a seal 125 is incorporated between the drive motor output shaft 124 and the base 109 to prevent leakage of the acoustic transmission medium.

  With the above configuration, the ultrasonic transducer assembly 101 can be swung around the swing shaft 104 by driving the drive motor 123 forward and reverse. Therefore, the electronic scanning of the plurality of ultrasonic transducers constituting the ultrasonic transducer assembly 101 and the mechanical scanning by the oscillation of the ultrasonic transducer assembly 101 around the oscillation axis 104 can be performed arbitrarily in the subject. It is possible to acquire a tomographic image and a stereoscopic image.

In order to obtain a stable image in an ultrasonic probe capable of acquiring an arbitrary tomographic image or stereoscopic image in the subject, it is necessary to operate the ultrasonic transducer assembly 101 stably. For this purpose, it was important to reduce the swing load. In response to such a problem, for example, as described in Patent Document 1, by using a voice coil motor as the drive motor, the power transmission means such as the belt 121 is eliminated, and the moment of inertia and the load on the power transmission means are eliminated. An ultrasonic probe that can reduce the oscillation load can be reduced.
JP-A-2-34154 (page 4, FIG. 3)

  However, in such a conventional ultrasonic probe, a large frictional load is generated by sliding between the output shaft of the drive motor or the rotary shaft constituting the encoder and the seal, and this frictional load varies between products. There was a problem that it fluctuates depending on the environmental temperature and long-term use. Therefore, in order to always operate the ultrasonic transducer assembly at a stable speed, a complicated control circuit that absorbs such a frictional load and a strict adjustment in a manufacturing process are required. In addition, when considering the product life, the wear between the rotating shaft and the seal is damaged most quickly compared to other parts. Therefore, to achieve a longer product life, it is necessary to improve the wear between the rotating shaft and the seal. there were.

  The present invention has been made to solve such a problem, and provides a highly reliable ultrasonic probe that can reduce the frictional load and can oscillate the ultrasonic transducer assembly stably for a long period of time. For the purpose.

  The ultrasonic probe of the present invention includes an ultrasonic transducer assembly in which a plurality of ultrasonic transducers that transmit and receive ultrasonic waves are arranged, a connection member that transmits and receives signals to and from the ultrasonic transducer assembly, An arm that supports the ultrasonic transducer assembly, a drive unit that swings the ultrasonic transducer assembly and the arm in a direction orthogonal to the arrangement direction of the ultrasonic transducers, and a swing that is a swing center of the arm A shaft, a bearing that supports the swing shaft, position detecting means for detecting the position of the ultrasonic transducer assembly, and a bell-shaped shape so as to cover the ultrasonic transmission / reception side of the ultrasonic transducer assembly An acoustic window disposed on the inside of the acoustic window, a liquid acoustic transmission medium that fills the periphery of the ultrasonic transducer inside the acoustic window, and a sealing unit that seals the acoustic transmission medium. The components constituting the means are It is configured such that sometimes does not have a sliding portion. With this configuration, the sliding load in the sealing portion is eliminated and the frictional load can be reduced, so that the ultrasonic transducer assembly can be oscillated stably for a long period of time.

  In the ultrasonic probe according to the present invention, the driving unit includes a coil integrally formed with the arm and having an axial direction perpendicular to the swing surface, and horizontally disposed on the swing surface on both sides of the coil. You may comprise from a pair of magnet and back yoke.

  With this configuration, since the small driving means can be arranged using simple components in the liquid acoustic transmission medium, it is possible to reduce the size of a highly reliable device that can stably swing for a long period of time at low cost.

  Further, the ultrasonic probe of the present invention may have a holding means for holding the ultrasonic transducer assembly in a predetermined position.

  With this configuration, the ultrasonic transducer assembly can be firmly fixed against vibration or shock when a still image is acquired, and thus a stable image can be obtained.

  The ultrasonic probe of the present invention may be configured to hold the ultrasonic transducer assembly when the holding means is not energized.

  With this configuration, since the ultrasonic transducer assembly is firmly fixed when not in use, it can be safely protected against vibration and impact.

  As described above, according to the present invention, the components constituting the sealing means for sealing the acoustic transmission medium are configured not to have a sliding portion when swinging. A highly reliable ultrasonic probe that can oscillate stably for a period of time can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  1 and 2 are sectional perspective views showing a configuration of a first embodiment of an ultrasonic probe according to the present invention.

  FIG. 2 is a partially cutaway view of FIG. The ultrasonic probe shown in FIGS. 1 and 2 includes an ultrasonic transducer assembly 1 in which a plurality of ultrasonic transducers (not shown) are arranged. The ultrasonic transducer assembly 1 includes an ultrasonic transducer. A lens that mechanically defines the focal point of the lens, a back cushioning material that suppresses transmission of ultrasonic waves to the back surface in the direction in which the ultrasonic waves are transmitted and received, a matching layer that matches acoustic impedance (all of which are not shown), and ultrasonic waves A connecting member 2 for transmitting and receiving an electric signal to and from the vibrator is integrally assembled together with the ultrasonic vibrator.

  The arm 3 is integrally coupled inside the ultrasonic transducer assembly 1 to support the ultrasonic transducer assembly 1. A swing shaft 4 serving as a swing center of the arm 3 is formed integrally with the arm 3 and is rotatably held by the bearing 5. A coil 6 a is integrally disposed with the arm 3 on the side opposite to the ultrasonic transducer assembly 1 across the swing shaft 4 of the arm 3. The coil 6a is electrically connected to an oscillation driving circuit (not shown) disposed in the ultrasonic probe or the ultrasonic apparatus main body.

  On both sides of the coil 6a, a pair of integrated magnets 6b and a back yoke 6c forming a magnetic circuit are arranged in such a direction that the magnet 6b side faces the coil. The coil 6a, the magnet 6b, and the back yoke 6c constitute the drive means 6, and a rotational torque around the swing shaft 4 is generated by flowing the coil 6a from the swing drive circuit.

  The outer circumference of the magnet rotor 7a is magnetized in the circumferential direction. The magnet rotor 7a is coaxially fixed to the swing shaft 4, swings together with the ultrasonic transducer assembly 1, and is fixed in the vicinity of the magnet rotor 7a. Detects the rotational position of the magnet rotor 7a. The magnet rotor 7a and the detector 7b constitute a position detecting means 7.

  The acoustic window 8 has a bell shape and is disposed so as to be surrounded from the ultrasonic transmission / reception side of the ultrasonic transducer assembly 1. The acoustic window 8 is filled with a liquid acoustic transmission medium (not shown) and contacts the non-analyte on the outside. Accordingly, the ultrasonic waves transmitted and received by the ultrasonic transducer assembly 1 are efficiently propagated between the subject through the acoustic transmission medium and the member of the acoustic window 8 without passing through the air layer.

  The base 9 is a support member that supports each component of the ultrasonic probe such as the bearing 5 and the back yoke 6c at a desired position. Further, the base 9 constitutes a sealing means in cooperation with the acoustic window 8, and is filled and sealed with an acoustic transmission medium in a sealed state.

  The casing 10 extends in the longitudinal direction facing the bell-shaped closed portion of the acoustic window 8 and is integrated with the acoustic window 8 to form the outer shape of the ultrasonic probe.

  The operation of the ultrasonic probe configured as described above will be described with reference to FIG. FIG. 3A shows the operation when a current is passed through the coil 6a in the direction of the arrow Ia. A magnetic circuit formed by a pair of integral magnets 6b and a back yoke 6c (one set not shown) generates a force in the direction of arrow Fa in the coil 6a, and the arm 3 in which the coil 6a is integrally formed The ultrasonic transducer assembly 1 operates in the direction of arrow U about the drive shaft 4 as a swing center. FIG. 3B shows the operation when a current is passed through the coil 6a in the direction Ib. Similarly, a force in the direction of arrow Fb is generated in the coil 6a, and the arm 3 and the ultrasonic transducer assembly 1 are moved in the direction of arrow V. Operate. Thus, the ultrasonic transducer assembly 1 can be swung in an arbitrary direction by switching the direction of the current flowing through the coil 6a. Here, the position of the ultrasonic assembly 1 is detected by the position detection means 7 shown in FIGS. In this manner, the ultrasonic transducer assembly 1 that acquires a planar image by electronic scanning is swung around the swing shaft 4 by the driving force of the driving means 6 including the coil 6a, the magnet 6b, and the back yoke 6c. Tomographic images and stereoscopic images can be acquired.

  In the embodiment of the present invention, all of the mechanically moving parts such as the arm 3 and the magnet yoke 7a of the driving means 6 and the position detecting means 7 in the above-described swinging operation are the acoustic transmission medium in the sealing means. Consists in. That is, it is not necessary to provide a seal or the like so that the liquid acoustic transmission medium does not leak around the movable part, and therefore the sliding portion can be eliminated. As described above, since the member constituting the sealing means is configured not to have a sliding portion at the time of swinging, the friction load at the time of swinging can be reduced, and further, variation in the friction load between products and the environment. Fluctuations due to temperature and long-term use can be reduced. Therefore, a stable swinging operation can be realized without carrying out a strict adjustment in a complicated control circuit or manufacturing process. Further, since the sliding wear between the seal and the moving parts is eliminated, the swing life is extended and the reliability is improved.

  Furthermore, in the embodiment of the present invention, the coil 6a that is integrally formed with the arm 3 and whose axial direction is perpendicular to the swing surface, and a pair of integral magnets that are horizontally disposed on the swing surface on both sides of the coil. Driving means is formed from 6b and the back yoke 6c. In this configuration, the coil 6a is formed to have substantially the same thickness as the arm 3, the magnet 6b is formed in a flat plate shape, and the back yoke 6c is formed by bending a part of the flat plate. However, it can be formed simply and easily. In addition, since the main planes of the respective parts are arranged substantially parallel to the swing surface, the arrangement can be performed with less space. As described above, since the small driving means can be arranged using simple components in the liquid acoustic transmission medium, the apparatus can be miniaturized at low cost.

  As described above, according to the first embodiment of the present invention, the components constituting the sealing means for sealing the acoustic transmission medium are configured so as not to have a sliding portion when swinging, and the driving means 6 is provided. The coil 6a, which is integrally formed with the arm and whose axial direction is perpendicular to the swing surface, and the magnet 6b and the back yoke 6c which are horizontally disposed on the swing surface on both sides of the coil, reduce the load for a long time. It is possible to provide a highly reliable small ultrasonic probe that can stably rock.

  Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5, the holding means 11 includes a plunger 11a, a pressurizing spring 11b, and a stator 11c, and the plunger 11a can be driven up and down by repeating energization and non-energization of the stator 11c. Here, the holding means 11 is arranged so that the plunger 11 a is below the swing shaft 4.

  FIG. 4 shows a state when the holding means 11 is not energized. At this time, there is no magnetic force between the plunger 11a and the stator portion 11c, and only the force of the pressurizing spring 11b acts to press the plunger 11a against the upper swing shaft 4. In this way, the oscillating shaft 4 can no longer rotate due to friction with the plunger 11a to be pressed, so that the ultrasonic transducer assembly 1 can be fixed.

  FIG. 5 shows a state where the holding means is energized. At this time, a coil (not shown) configured inside the stator 11c is energized, and a magnetic force acts on the plunger 11a, which is a soft magnetic material, so that the magnetic force overcomes the spring force of the pressurizing spring 11b. Moves away from the swing shaft 4 and moves downward. Thereby, the ultrasonic transducer assembly 1 can swing.

  As described above, the ultrasonic assembly 1 is fixed at an arbitrary position by de-energizing the holding means 11, and can be freely rocked by being energized to be fixed. Accordingly, when the ultrasonic transducer assembly 1 is stationary and a two-dimensional image is obtained using electronic scanning in the arrangement direction of the plurality of ultrasonic transducers, the holding means 11 is not energized, and the ultrasonic transducer assembly 1 is fixed. Even if an impact or the like is applied, the ultrasonic transducer assembly 1 can be obtained without shaking, and the holding means 11 is energized when the ultrasonic transducer assembly 1 is swung, such as when acquiring a stereoscopic image. The ultrasonic transducer assembly 1 can be arbitrarily swung. Further, when the ultrasonic transducer assembly 1 is not used, the ultrasonic transducer assembly 1 can be safely fixed by retracting the ultrasonic transducer assembly 1 to a safe position and then de-energizing the holding means 11.

  As described above, according to the second embodiment, the holding unit 11 that holds the ultrasonic transducer assembly 1 in a predetermined position is provided, and the holding unit 11 holds the ultrasonic transducer assembly 1 when not energized. Therefore, when acquiring a two-dimensional image by electronic scanning, the ultrasonic transducer assembly 1 can be firmly fixed against vibration and shock, and a stable image can be obtained. In contrast, the ultrasonic transducer assembly 1 does not move and can be safely protected.

  As described above, the ultrasonic probe according to the present invention has an effect that the ultrasonic transducer assembly can be stably oscillated for a long period of time with little frictional load at the time of oscillating. It is useful as an ultrasonic probe or the like used in an ultrasonic diagnostic apparatus that uses it to obtain an image in a subject.

Sectional perspective view of the ultrasonic probe in the first embodiment of the present invention Detailed view of the inside of the ultrasonic probe in the first embodiment of the present invention The figure which shows rocking | fluctuation operation | movement in the 1st Embodiment of this invention The figure which shows the holding | maintenance state of the ultrasonic vibration assembly in the 2nd Embodiment of this invention. The figure which shows the state by which the holding state of the ultrasonic vibration assembly in the 2nd Embodiment of this invention is open | released Cross-sectional perspective view of a conventional ultrasonic probe

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Ultrasonic vibrator assembly 2,102 Connection member 3,103 Arm 4,104 Oscillating shaft 5,105 Bearing 6 Driving means 6a Coil 6b Magnet 6c Back yoke 7 Position detecting means 7a Magnet yoke 7b Detector 8, 108 Acoustic window 9,109 Base 10 Case 11 Holding means 11a Plunger 11b Pressure spring 11c Stator 120 First pulley 121 Belt 122 Second pulley 123 Drive motor 124 Drive motor output shaft 125 Seal

Claims (4)

An ultrasonic transducer assembly in which a plurality of ultrasonic transducers for transmitting and receiving ultrasonic waves are arranged, a connection member that transmits and receives signals to and from the ultrasonic transducer assembly, and an arm that supports the ultrasonic transducer assembly , A driving means for swinging the ultrasonic transducer assembly and the arm in a direction orthogonal to an arrangement direction of the ultrasonic transducers, a swing shaft serving as a swing center of the arm, and the swing shaft are supported. A bearing, position detection means for detecting the position of the ultrasonic transducer assembly, an acoustic window having a bell shape and arranged to cover the ultrasonic transmission / reception side of the ultrasonic transducer assembly, and the acoustic A component constituting the sealing means in an ultrasonic probe having a liquid acoustic transmission medium filling the periphery of the ultrasonic transducer inside a window and a sealing means for sealing the acoustic transmission medium Is said rocking Ultrasonic probe is characterized in that no sliding portion. The driving means includes a coil integrally formed with the arm and having an axial direction perpendicular to the swing surface, and a pair of integral magnets and a back yoke disposed horizontally on the swing surface on both sides of the coil. The ultrasonic probe according to claim 1. 3. The ultrasonic probe according to claim 2, further comprising holding means for holding the ultrasonic transducer assembly in a predetermined position. 4. The ultrasonic probe according to claim 3, wherein the holding means holds the ultrasonic transducer assembly when not energized.

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