JP2997101B2 - Mechanical scanning ultrasonic probe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical scanning ultrasonic probe which is used in a medical ultrasonic diagnostic apparatus and performs scanning (scanning) of an ultrasonic beam by mechanical operation of a transducer.

[0002]

2. Description of the Related Art A conventional mechanical scanning ultrasonic probe used in a medical ultrasonic diagnostic apparatus performs scanning by mechanically rotating or swinging a transducer by driving a motor.

FIG. 2 shows the configuration of a conventional mechanical scanning ultrasonic probe. 1 is a transducer, 2 is a rotor,
Reference numeral 3 denotes a rotating shaft, 4 denotes a rotating shaft supporting member, and the transducer 1 comprises a rotor 2, a rotating shaft 3 and a rotating shaft supporting member 4.
With this, a rotation operation can be performed.

[0004] 5 is a motor, 7 is a pinion gear, 8 is an orthogonal conversion gear, 9 is a driving pulley, 10 is a timing belt,
11 is a driven pulley. The rotational motion of the motor 5 is transmitted to the rotor 2 via a transmission system such as a pinion gear 7, an orthogonal conversion gear 8, a driving pulley 9, a timing belt 10, and a driven pulley 11.

[0005] A transducer 1 is fixed to the rotor 2. An encoder 6 is attached to the motor 5 and detects a rotation position of the motor 5. On the basis of the information obtained by the position detection by the encoder 6, the control circuit (not shown) controls the rotation of the motor 5.

14 is an acoustic window, 12 is an oil seal, 13
The acoustic coupling liquid 13 is filled inside the acoustic window 14. With the oil seal 12, the motor 5
The acoustic coupling liquid 13 is sealed so that it does not leak through the rotation shaft of.

Next, the operation of the above configuration will be described.
In FIG. 2, when the motor 5 rotates, the rotor 2 rotates via a drive transmission system such as a pinion gear 7, a driving pulley 9, and a timing belt 10, and the transducer 1 fixed to the rotor 2 rotates. This rotation angle is detected by an encoder 6 attached to the motor 5 and an ultrasonic signal is supplied to the transducer 1. Ultrasonic waves from the transducer 1 are emitted to the human body through the acoustic coupling liquid crystal 13 and the acoustic window 14. The reflected wave of the radiated ultrasonic wave is sent to the acoustic window 1
4. The signal is received through the acoustically coupled liquid crystal 13 and the transducer 1, and the received signal is processed and displayed on an ultrasonic diagnostic apparatus main body (not shown).

As described above, even with the above-described conventional mechanical scanning ultrasonic probe, the scanning can be performed mechanically by rotating the transducer 1 through the drive transmission system by the rotational movement of the motor 5.

[0009]

However, in the above-mentioned conventional mechanical scanning ultrasonic probe, although the rotation speed of the motor 5 is controlled by the output signal of the encoder 6 to be constant, the drive transmission is performed. The rotor 2 is rotated through the system. For this reason, the rotational position of the rotor 2 changes due to the rotation axis eccentricity of the pinion gear 7 and the drive pulley 9 of the transmission system. If the received signal from the transducer 1 is displayed as an image, image distortion and There has been a problem that a display image effective for diagnosis cannot be obtained due to image fluctuation.

Further, since the rotational movement transmitting mechanism of the motor 5 is provided in the acoustic window 14 sealed with the acoustic coupling liquid 13, the oil seal 12 for sealing the acoustic coupling liquid 13 must be provided in the middle of the transmission system. This oil seal 1
2, there is a problem that the rotational load increases and the reliability of sealing is lacking.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and reduces a rotational position error of a rotor at the time of a scanning operation to obtain a display image effective for diagnosis. Can be stopped, high reliability is obtained, and
It is an object of the present invention to provide an excellent mechanical scanning ultrasonic probe that can be reduced in size.

[0012]

In order to achieve the above object, the present invention provides a transducer for transmitting and receiving ultrasonic waves,
A rotor on which the transducer is disposed, a shaft fixed to a shaft holding member in a direction orthogonal to the ultrasonic scanning surface of the transducer, and rotatably supporting the rotor; and a shaft fixed to one side of the rotor and rotated together with the rotor. the detecting the magnet, and a motor coil fixed to the shaft opposite to the magnet, the rotational speed and the stop position of the rotor through a detection plate that rotates together with the rotor is fixed to the other side of the rotor Rotor and shaft holding member
, A slip ring fixed to the other side surface of the rotor and rotating with the rotor, and a signal transmission for transmitting / receiving a signal to / from the transducer via a contact that presses the slip ring. Means and an acoustic window for covering a rotating portion of the rotor including a connecting portion between the shaft holding member and the shaft, and for filling and sealing an acoustic coupling liquid.

[0013]

Therefore, the mechanical scanning type ultrasonic probe of the present invention has a structure in which the rotor on which the transducer is disposed, the motor and the operation detecting means are integrally formed, so that the scanning operation can be performed without a drive transmission system. And the rotational position error of the rotor during the scanning operation is reduced, a display image effective for diagnosis is obtained, and the acoustic coupling liquid to be sealed can be completely sealed, and high reliability is obtained. Can be downsized.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the mechanical scanning ultrasonic probe of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows the configuration of the embodiment. In FIG. 1, reference numeral 25 denotes an acoustic window which is an outer housing;
Acoustic coupling liquid filled inside. 28 is a base member. Reference numeral 30 denotes a transducer (corresponding to an operation detecting means), 31 denotes a rotor, 32a denotes an encoder rotating plate provided with a slit, 32b denotes an encoder detecting unit,
2c is an encoder detection line. Slip ring 33 performs the connection electrical contact during rotation transducer 30, 3
4 is a shaft, 35 is a signal line, 36 is a magnet, 37 is a motor coil, 38a and 38b are shaft holding members protruding from the base member 25, 39a is a motor cover, 39b is a motor connection line, and 40 is a bearing.

The transducer 30 is fixed to the rotor 31. The rotor 31 has a bearing 40, a shaft 34,
It is held by the shaft holding members 38a and 38b so as to be able to rotate.

Further, a motor 39 and an encoder rotating plate 32a are attached to both sides of the rotor 31. Also,
The motor 39 has a motor coil 37 fixed to the shaft 34 and a magnet 36 attached to the rotor 31 to rotate.
That is, it has the structure of the outer rotor type motor. Slip ring 33 is attached to the other side of rotor 31
The slip ring 33 is connected to the signal line 35
Contact is pressed and the rotor 31 rotates.
In this case, the contact slides on the upper surface of
A pneumatic connection is made .

The rotation of the encoder rotary plate 32a is detected by an encoder detector 32b to detect the rotational position of the motor 39, that is, the rotor 31. Based on the detected position information obtained by the encoder detection unit 32b, the motor 3
9 is controlled by a control circuit (not shown).

Next, the operation of the above configuration will be described.
When a current flows through the motor coil 37, the magnet 3 of the motor 39
6, a rotation force is generated, and the rotor 31 rotates. The rotational position of the rotor 31 is detected by an encoder detector 32b attached to the side surface of the rotor 31. By controlling the rotation of the rotor 31, the scanning operation of the transducer 30 fixed to the rotor 31 is performed.

When an ultrasonic signal is applied to the transducer 30 via the signal line 35 and the slip ring 33 during the scanning operation of the transducer 30, the ultrasonic wave is emitted from the transducer 30. The reflected ultrasonic waves from the body (not shown) from which the ultrasonic waves are radiated are converted into electric signals by the transducer 30 and are transmitted to the slip ring 3.
3. The signal is transmitted to an ultrasonic diagnostic apparatus (not shown) through the signal transmission path of the signal line 35. Here, after performing the signal processing, it is displayed as an ultrasonic image.

As described above, according to the above embodiment, the scanning operation of the transducer 30 is controlled by the motor 39 and the encoder 32 integrally formed with the rotor 31 to which the transducer 30 is fixed. This eliminates the need for a drive transmission system for transmitting the rotational motion of the rotor 31 to the rotor 31, simplifies the structure, and realizes small size, light weight, and high reliability.

Further, since the motor 39 and the encoder 32 serving as the position detecting means are integrally formed with the rotor 31, the bias of the gear is changed like the conventional mechanical scanning type ultrasonic probe shown in FIG. Accuracy of parts of drive transmission system such as core
A rotation control error due to assembly accuracy does not occur, and distortion and shaking of the ultrasonic image can be eliminated.

Further, since there is no drive transmission system, the acoustic coupling liquid can be sealed without using an oil seal or the like.
The load on the motor 39 can be reduced, and leakage of the acoustic coupling liquid from the oil seal can be prevented, so that reliability can be improved.

Further, by adopting an outer rotor type motor, the motor 39 can be integrally formed with the rotor 31, the portion of the rotor 31 is reduced, the tip of the ultrasonic probe is reduced in size, and the body cavity is reduced. A shape suitable for an ultrasound probe for internal diagnosis can be easily realized.

[0025]

According to the present invention, as is apparent from the above embodiment, the rotor is rotatably supported on the fixed shaft, the magnet and the operation detecting means are mounted on the rotor, and the coil is mounted on the fixed shaft. Since the outer rotor type motor and the rotor on which the transducer is arranged are integrally configured, the scanning operation can be performed without the need for a drive transmission system, and the rotational position error of the rotor during the scanning operation is reduced, Since the size of the probe can be reduced, a display image suitable for diagnosis in a body cavity and effective for diagnosis can be obtained. In addition, a structure in which the shaft penetrates the outer housing surface as compared with the case where the shaft is fixed to the outer housing by holding the shaft with a shaft holding member separate from the acoustic window which is the outer housing. In the case of taking the above, the watertightness is reduced, but the sealed acoustic coupling liquid can be completely sealed. Further, since the shaft can be prevented from being distorted by the pressure from the outside, there is an effect that high reliability can be obtained. In addition, in a state where the rotor on which the transducer is arranged is continuously rotated in one direction, ultrasonic waves are directly transmitted and received from the transducer to the subject in front of the probe to obtain a tomographic image. This has the effect that an image with a wide scanning angle in a forward sector can be extracted in a high image quality state.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a conventional mechanical scanning ultrasonic probe.

[Explanation of symbols]

 Reference Signs List 30 Transducer 31 Rotor 32 Encoder 32a Encoder rotating plate 32b Encoder detector 34 Axis 36 Magnet 37 Motor coil 38a, 38b Axis holding member 39 Motor

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Michiyo Kikumazuka 4-3-1 Tsunashima Higashi, Kohoku-ku, Yokohama City, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. (56) References JP-A-64-27538 (JP, A) JP-A-58-46950 (JP, A) JP-A-62-233150 (JP, A) JP-A-63-21045 (JP, A)

Claims (1)

(57) [Claims] 1. A transducer for transmitting and receiving ultrasonic waves, a rotor on which the transducer is arranged, and a shaft fixed to a shaft holding member in a direction orthogonal to an ultrasonic scanning surface of the transducer and rotatably supporting the rotor. A magnet fixed to one side of the rotor and rotating with the rotor, a motor coil fixed to the shaft opposite to the magnet, and a detection plate fixed to the other side of the rotor and rotating with the rotor. The rotor and the shaft holder for detecting the rotation speed and the stop position of the rotor
An operation detecting means provided between the holding member, a slip ring fixed to the other side surface of the rotor and rotating with the rotor, and a signal for transmitting and receiving signals to and from the transducer via a contact that presses the slip ring. Signal transmitting means, and an acoustic window for covering a rotating portion of the rotor including a connecting portion between the shaft holding member and the shaft, and for filling and sealing an acoustic coupling liquid, and energizing the motor coil and A mechanical scanning ultrasonic probe that continuously rotates and drives a rotor in one direction to transmit and receive ultrasonic waves from the transducer.