JPS63281633A - Ultrasonic endoscopic apparatus - Google Patents

Abstract

PURPOSE:To prevent the generation of the noise caused by a contact system and to perform the transmission of a signal in spite of a small scale, by forming a signal transmitting means for converting the signal received by a rotationally driven ultrasonic vibrator to a magnetic signal and converting said magnetic signal to an electric signal in a non-contact system by utilizing galvanomagnetic effect. CONSTITUTION:A magnetic resistor element 17 showing galvanomagnetic effect is fixed in opposed relation to a coil 10 on the center axis of said coil 10 and an amplifying circuit 18 is provided behind said element 17 and amplifies a receiving signal to transmit the same to an external apparatus 4. In the ultrasonic endoscopic apparatus thus constituted, the signal received by an ultrasonic vibration part 6 is transmitted to a coaxial cable 16 and amplified by an amplifier 11 to enter the coil 10. The magnetic field of the coil 10 is detected by the MR element 1 to be converted to an electric signal which is, in turn, transmitted to the external apparatus 4 through the amplifying circuit 18. Herein, the element converting the magnetic field to the electric signal is put to practical use by the use of the MR element regenerating high density magnetic recording such as VTR and, since the size of the element is small, the apparatus can be made more small-scale in the case used in an ultrasonic endoscopic apparatus.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ultrasonic endoscope in which a received signal of a rotationally driven ultrasonic transducer is transmitted by a signal transmitting means using a current magnetic effect. Regarding equipment.

[Prior Art] A conventional ultrasonic endoscope device rotates and scans an ultrasonic ffi element 51 built into the tip of an endoscope using a flexible shaft, as shown in FIG. 6, the electrical configuration of which is shown. In the mechanical radial scanning type, the vibrator 51
Signal 1 connected to ;! One side of the signal transmitted by the terminal 52 is grounded through brush contacts 53 and 54, and the other side is led to a transmission pulse generation circuit 57 through an external reception display VT device 55 and a noise cutting diode 56.

In this way, in the ultrasonic endoscope device using the brush contacts 53, 54, the brush contacts 53, 54 may be momentarily separated during rotation, or due to changes in the contact potential difference between the contacts that make up the brush, the received weak Noise is mixed into the ultrasound signal, and Ii
This has the disadvantage that it appears as noise when displaying a layered image, making the tomographic image difficult to see. Also, JP-A-58-41539
Store the motor at the tip as shown in the issue,
There are also devices in which a vibrator is attached to the rotating shaft, but they have the same drawbacks as the one shown in FIG.

For this reason, there is a conventional example shown in FIG. 7 that alleviates the above drawbacks.

That is, a preamplifier 58 is provided on the rotated side shown by the broken line to amplify the ultrasonic signal received by the transducer 51. This amplifier 58 also rotates in synchronization with the rotation of the vibrator 51, so there is a brush contact 59 that supplies current, a brush contact 60 that outputs the output signal of the amplifier 58 to the outside, a brush contact 61 for common signal, and a transmission pulse. A brush contact 62 for application is required.

Note that the noise cutting diode 56 is also provided on the rotating part side. In the ultrasonic endoscope device configured in this way, the received ultrasonic signal is passed through the simulated brush contact 60 which has been amplified once, so that the noise voltage generated at the brush contact 60 is transmitted to the brush contact 53 in FIG. If the noise voltage is the same, an improvement in S/N can be expected than in the configuration shown in FIG.

[Problems to be Solved by the Invention] However, since the DC current for the power supply is superimposed on the signal current and flows through the brush contact 61 provided on the common signal line, brush noise becomes a problem due to this DC current. However, there is a drawback that noise appears in the displayed image.

For this reason, the present applicant proposed a related technology example in which signals are transmitted using a rotary transformer in Japanese Patent Laid-Open No. 103436/1983. Although this related technology example is non-contact and solves the above-mentioned drawbacks, it is difficult to miniaturize it at present. Therefore, something that can be made smaller and has similar functions is desired.

The present invention has been made in view of the above-mentioned points, and provides an ultrasonic endoscope device that can transmit signals received by a rotationally driven ultrasonic transducer in a non-contact manner and is also suitable for miniaturization. The purpose is to

[Means and effects for solving the problem] In the present invention, a signal received by a rotationally driven ultrasonic transducer is converted into a magnetic signal, and this magnetic signal is converted into an electric signal without contact using the current magnetic effect. By forming the signal transmitting means, it is possible to transmit signals in a small size and without the generation of noise in the contact method.

[Example code] Hereinafter, the present invention will be specifically explained with reference to the drawings.

FIG. 1 shows an ultrasonic endoscope apparatus according to a first embodiment of the present invention.

As shown in FIG. 1, the ultrasonic endoscope apparatus 1 of the first embodiment is connected to an ultrasonic endoscope 2 provided with ultrasonic transmitting/receiving means, and this ultrasonic endoscope Ii2 via a coaxial cable 3. and an external device 4. In the ultrasonic endoscope 2, an ultrasonic transducer 6 is disposed at the tip of an insertion section 5 which has a small diameter so that it can be inserted into a body cavity, and the rear end of the flexible shaft 7 is inserted into a sub-operation section 8. It is connected to the rotating part 9.

A coil 10 is arranged at the rear end of the rotating part 9,
The rotating section 9 houses a vibrator driving amplifier 11, a transmitting section 12, a transmitting/receiving switching section 13, and the like.

The rotational power of the motor 14 is transmitted to the flexible shaft 7 and the rotating part 9 via a belt 15, and the ultrasonic transducer 6 and the coil 10 are rotationally driven.

The ultrasonic transducer 6 is excited with ultrasonic waves by applying high-frequency pulses from the transmitter 12, and is driven to rotate and emit ultrasonic waves radially over an appropriate angular range to perform mechanical radial scanning. . Therefore, it is reflected at the boundary surface of the object with different acoustic impedance, and the oscillator 5
Received at. The signal converted into an electrical signal by the vibrator 6 is input to the rotating section 9 via the coaxial cable 6 inserted through the flexible shaft 7. The signal is then input to the amplifier 11 via the transmission/reception switching section 13, amplified, and then transmitted to the coil 10 at the tip of the rotating section 9. coil 1
A magnetoresistive element (Magneto-resistive element) that faces the central axis of 0 and exhibits a current magnetic effect W.
(abbreviated as MR element) 17 is fixed, and then an amplifier circuit 18 is provided to amplify the received signal and transmit it to the external device 4. In the ultrasonic endoscope apparatus having such a configuration, a signal received by the ultrasonic transducer 6 is transmitted through the coaxial cable 16, amplified by the amplifier 11, and then input to the coil 10. It is well known that a magnetic field is created when current flows through the coil 10, and this magnetic field is detected by the MR element 17, converted into an electrical signal, and transmitted to the external device 4 via the amplifier circuit 18. The element that converts a magnetic field into an electric signal is an MR element that has been put into practical use for reproducing high-density magnetic recording in VTRs, etc., and because the element is small, it is used in ultrasound endoscope equipment. This allows the device to be made more compact.

It should be noted that the transmitter 12 within the rotating section 9. Power may be supplied to the amplifier 11 and the like from the outside using a built-in battery or a brush contact and a diode as disclosed in JP-A-61-103436.

FIG. 2 shows the main parts of a second embodiment of the invention.

In this second embodiment, an MR element 17 is disposed opposite to a coil 10, and the MR element 17 and an MR element 21 having uniform characteristics are connected in series by arranging the coil 10 so that it does not receive the magnetic flux or magnetically shielding it. Then, with the voltage E applied to these MR elements 17 and 21 connected in series, the MR element 17
The voltage at both ends is detected.

In this second embodiment, MR elements 17 and 21 with uniform characteristics are used.
By using one, it is possible to be less affected by changes in output due to temperature than in the case of one.

FIG. 3 shows the main parts of a third embodiment of the present invention.

In this third embodiment, the signal is amplified by an amplifier 11, converted into a digital signal by an A/D converter 31, converted into a serial signal by a parallel-to-serial converter 32, and then applied to the coil 10. On the other hand, the output of the MR element 17 placed opposite to the coil 1o is transmitted to the amplifier circuit 18.
After passing through the signal, the signal is shaped by a waveform shaper 33 and converted into a binary signal.

This binary signal is converted into parallel data by an external serial/parallel converter 34 via a cable 3, and this parallel data is returned to an analog signal by a D/A converter 35. Incidentally, in FIG. 3, the serial/parallel converter 34 and the D/A converter 35 may be housed within the external device 4 or may be housed within the sub-operation section 8.

FIG. 4 shows a fourth embodiment of the invention.

In this fourth embodiment, instead of using the MR element, a Hall element 41 having a galvanomagnetic effect is used. coil 10
A current is supplied from the power supply Vc to the Hall element 41 disposed opposite to the hall element 41, and the magnetic field detection output is inputted to the differential amplifier 42, so that a linear differential output is obtained from the differential amplifier 42. Note that this amplifier 42 has a variable resistor 4.
Offset voltage compensation can be performed by 3.

FIG. 5 shows the main parts of a fifth embodiment of the present invention.

In this embodiment, for example, as shown in FIG. 2, the output signal of the amplifier 11 is FM-modulated by an FM modulator 45 and then applied to the coil 10.

Further, the output of the amplifier circuit 18 is demodulated by an FM demodulator 46 and then led to the external device 4 via the cable 3.

In this way, the noise is generally an AM wave, and it is possible to transmit a signal with excellent noise resistance.

In addition, in the fourth embodiment, as in the third embodiment, two
It is also possible to convert it into a digital signal and transmit it.

[Effects of the Invention] As described above, according to the present invention, since signals are transmitted between the rotating part and the non-rotating part without contact using the current magnetic effect, noise caused by contact is reduced. It can eliminate contamination and can be made smaller.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of the first embodiment of the present invention, FIG. 2 is a configuration diagram showing the main parts of the second embodiment of the invention, and FIG. 3 is a diagram showing the main parts of the third embodiment of the invention. Fig. 4 is a block diagram showing the main parts of the fourth embodiment of the present invention, Fig. 5 is a block diagram showing the main parts of the fifth embodiment of the invention, and Fig. 6 is the electrical diagram of the conventional example. FIG. 7 is a circuit diagram showing the main parts of the electrical system in another conventional example. 1... Ultrasonic endoscope @if 2... Ultrasonic endoscope 4... External device 5... Insertion section 6...
(Ultrasonic) 31i mover 9... Rotating part 10... Coil 11... Amplifier 17... MR element
18... Amplifier circuit Figure 1 Figure 3 Figure 2 Figure 4 Figure 5

Claims (1)

[Claims] In a mechanical radial scanning type ultrasonic endoscope device that rotates an ultrasonic transducer provided at the tip of the endoscope via a rotation transmission member, the ultrasonic transducer of the rotating tip uses current magnetic effect. An ultrasonic endoscope device characterized in that a signal received by a sonic transducer is transmitted to a non-rotating part.