JP2008188246A - Ultrasonic probe, ultrasonic diagnostic apparatus and method for controlling output of ultrasonic probe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic probe which automatically adjusts its gain to a predetermined value in accordance with changes of signal levels of output signals when the ultrasonic probe is connected to an ultrasonic diagnostic apparatus. <P>SOLUTION: The ultrasonic probe has a plurality of vibrators 102 that transmit ultrasonic beams in response to a signal from a transmission means arranged on the ultrasonic diagnostic apparatus 200 and receive ultrasonic echoes reflected by a subject. The ultrasonic probe further has level adjusting means 103 which correspond to the vibrators 102 for changing the magnitude of output signals from the vibrators 102 and for supplying the signals to a receiving means arranged on the ultrasonic diagnostic apparatus 200, level detecting means 104 for detecting the magnitude of the output signals from the level adjusting means 103, a reference value generation means 106 for generating a reference value of a predetermined magnitude, and a control means 109 that compares the outputs from the level detection means 104 with the reference value and controls gains of the level adjusting means 103 so as to conform the outputs and the reference value with each other. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic probe that scans a living body with an ultrasonic beam to acquire an ultrasonic echo, an ultrasonic probe output control method that controls the output of the ultrasonic probe, and an ultrasonic probe connected to the ultrasonic probe. The present invention relates to an ultrasonic diagnostic apparatus for obtaining an in-vivo ultrasonic tomogram from the obtained ultrasonic echo. More specifically, the present invention relates to an ultrasonic probe including a variable gain amplifier that amplifies an ultrasonic echo.

  In an ultrasonic diagnostic apparatus that irradiates a subject with an ultrasonic beam and receives a reflected ultrasonic echo to generate a real-time ultrasonic tomographic image, the reflected ultrasonic echo is weak. A preamplifier is provided to amplify a signal to be output to the ultrasonic diagnostic apparatus (see, for example, Patent Document 1). The configuration of such an ultrasonic diagnostic apparatus will be described with reference to FIG. Here, FIG. 6 is a diagram of a configuration of an ultrasonic diagnostic apparatus including a conventional ultrasonic probe.

  The ultrasonic diagnostic apparatus main body 200 includes a transmission / reception circuit 210, an ultrasonic diagnostic apparatus side connector 201, a signal processing unit 202, an image processing unit 203, a control circuit 204, a display unit 205 as a user interface, and an operation panel 206. .

  The transmission / reception circuit 210 includes a transmission delay circuit 211, a pulsar 212, a preamplifier 213, a transmission / reception changeover switch 214, and a reception delay addition circuit 215. The transmission / reception circuit 210 is connected to the ultrasonic probe 100 via the ultrasonic diagnostic apparatus side connector 201 and the probe connector 120.

  The transmission delay circuit 211 generates drive signals having different timings for each transducer 102. The pulser 212 receives a drive signal from the transmission delay circuit 211 and generates an electric pulse of a predetermined level. The transmission / reception changeover switch 205 switches the switch to the transmission side to the ultrasonic probe 100 and passes the electrical pulse generated by the pulser 212 to the ultrasonic probe 100 side. Furthermore, the transmission / reception changeover switch 205 switches the switch to the preamplifier 213 side, and passes the ultrasonic echo sent from the transducer 102 to the preamplifier 213 side. Here, the transmission / reception changeover switch 205 is composed of a non-linear element such as a semiconductor diode, and transmits a transmission waveform having a large amplitude output from the pulsar 212 to the ultrasonic probe 100 side and is sent from the vibrator 102. A simple echo has a function of passing to the preamplifier 213 side. The preamplifier 213 amplifies the received ultrasonic echo and transmits it to the transmission / reception delay adding circuit 215. The reception delay adding circuit 215 aligns the timing of the amplified ultrasonic echo for each transducer 102 and transmits it to the signal processing unit 202.

  The ultrasonic probe 100 includes a plurality of transducer groups 102 arranged in an array of one row. The transducer group 102 receives an electrical pulse from the transmission / reception circuit 210 and radiates an ultrasonic beam having a designated directionality to the subject. The ultrasonic beam is reflected at an interface having different acoustic impedance such as a boundary of a structure in the subject, and returns to the transducer group 102 as an ultrasonic echo. The transducer group 102 receives an ultrasonic echo for each transducer and sends it to the transmission delay circuit 211.

  The signal processing unit 202 extracts the envelope of the ultrasonic echo by detection processing and transmits it to the image processing unit 203.

  The image processing unit 203 performs coordinate conversion of the received envelope according to the cross section of the subject, performs gradation processing suitable for image display, and the like, and causes the display unit 205 to display.

  Through the processing as described above, the ultrasonic diagnostic apparatus can display an ultrasonic tomographic image as morphological information in the subject as shown in FIG. 7 in real time. FIG. 7 is a schematic diagram of an ultrasonic tomographic image (B mode image) obtained in a normal mode in which an ultrasonic beam is emitted in a pulse shape.

  Further, when the transmission / reception circuit 210 transmits / receives an ultrasonic pulse with the center frequency f0 to / from the blood flow in the subject, the frequency of the ultrasonic beam is changed by the blood cell flowing, and the Doppler shift fd proportional to the blood flow velocity. In response, an ultrasonic echo having a frequency of f0 + fd is received. The signal processing unit 202 detects the Doppler shift frequency fd, and the image processing unit 203 displays the temporal change of the Doppler shift frequency fd, so that a blood is displayed on the display unit 205 as a PW Doppler image (not shown). Flow velocity information can be displayed. Further, the image processing unit 203 two-dimensionally maps the Doppler shift frequency fd, performs appropriate color conversion, and then superimposes the color Doppler image (not shown) on the ultrasonic tomogram in FIG. Can be displayed.

  In the ultrasonic probe used in the ultrasonic diagnostic apparatus that displays a real-time ultrasonic tomographic image as described above, conventionally, the number of transducers provided in the ultrasonic probe is 100 to 200. On the other hand, in recent years, an ultrasonic probe in which the number of transducers to be deployed is increased to 1000 to 2000 has been provided for the purpose of creating a finer ultrasonic tomographic image. However, since the size of the ultrasonic probe does not change, when the number of transducers is increased in this way, the transducers become smaller, and the echo signal received by one transducer becomes weak. Therefore, in order to transmit this weak echo satisfactorily, an ultrasonic probe having a built-in electronic circuit such as a preamplifier and a buffer matched with the main body of the ultrasonic diagnostic apparatus to be connected has been used. In the case of such an ultrasonic probe, a large-amplitude transmission pulse supplied from the main body of the ultrasonic diagnostic apparatus is transmitted to the vibrator so as not to damage these electronic circuits built in the ultrasonic probe. Therefore, a transmission / reception changeover switch is also built in the probe head.

JP 2006-1116018 A

  This type of ultrasonic probe has a built-in electronic circuit and outputs weak ultrasonic echoes to each channel (output system from each transducer) to the transmitter / receiver circuit after processing such as low noise amplification or buffering. In order to reduce heat generation and power consumption in the probe body, a load resistance group is provided on the ultrasound diagnostic device body side, current is output from the ultrasound probe, and converted to a signal voltage at the input part of the ultrasound diagnostic device body In general, a current output type configuration is used. By using the input impedance of the preamplifier of the transmission / reception circuit as it is, it is possible to make a configuration that does not require a separate load resistance, but the input impedance differs depending on the ultrasonic diagnostic apparatus body, and even in the same ultrasonic diagnostic apparatus body, it varies depending on the channel. The size varies.

  For this reason, when this type of ultrasonic probe is connected to the ultrasonic diagnostic apparatus body, the signal level changes due to the difference in the ultrasonic diagnostic apparatus, resulting in a level difference. Further, a level difference also occurs in signals between channels due to deviations in input impedance between channels. Due to the difference in signal level, when the signal level is lowered, it is easily affected by noise, and when the signal level is excessive, the signal is saturated to cause distortion.

  In addition, the level difference between channels causes the formation of an ultrasonic beam to be non-uniform, which causes a reduction in sensitivity and lowers the spatial resolution and contrast resolution, which adversely affects image quality.

  The present invention has been made in view of such circumstances, and automatically adjusts the gain of the ultrasonic probe to a predetermined value regardless of the change in the signal level of the output signal when connected to the ultrasonic diagnostic apparatus body. An object is to provide an ultrasonic probe.

  In order to achieve the above object, an ultrasonic probe according to claim 1 receives a signal from a transmission means provided on the ultrasonic diagnostic apparatus main body side, transmits an ultrasonic beam to the subject, An ultrasonic probe comprising a plurality of transducers for receiving reflected ultrasonic echoes, the magnitude of an output signal from the transducer corresponding to the transducer being changed, and the ultrasonic diagnostic apparatus main body Level varying means for supplying to the receiving means provided on the side, level detecting means for detecting the magnitude of the output signal from the level varying means, reference value generating means for generating a reference value of a predetermined magnitude, Control means for comparing the output from the level detection means with the reference value and controlling the gain of the level variable means so that they match.

  The ultrasonic diagnostic apparatus according to claim 5 includes an ultrasonic probe, a transmission / reception unit that scans and receives an ultrasonic wave through the ultrasonic probe, and an ultrasonic wave based on data received by the transmission / reception unit. An ultrasonic diagnostic apparatus comprising an image generation means for generating a sound wave image and displaying it on a display means, wherein the ultrasonic probe receives a signal from a transmission means provided on the ultrasonic diagnostic apparatus body side and receives the ultrasonic wave A plurality of transducers for transmitting a beam to the subject and receiving ultrasonic echoes reflected by the subject, and changing the magnitude of an output signal from the transducer corresponding to the transducer; Level varying means for supplying to the receiving means provided on the ultrasonic diagnostic apparatus main body side, level detecting means for detecting the magnitude of the output signal from the level varying means, and a reference value for generating a reference value of a predetermined magnitude Generation means Compares the output with the reference value from the level detecting means, is characterized in that a control means they controls the gain of said level varying means to match.

  The ultrasonic probe output control method according to claim 6 includes a step of switching to a calibration mode for calibrating the output of the variable level means, and a plurality of signals received from a transmission means provided on the ultrasonic diagnostic apparatus main body side. The step of transmitting an ultrasonic beam from the transducer to the subject, the step of receiving the ultrasonic echo reflected by the subject by the plurality of transducers, and the magnitude of the output signal from the transducer by the level varying means A level changing step of changing the height and supplying the receiving unit provided on the ultrasonic diagnostic apparatus main body side, a level detecting step of detecting the magnitude of the output signal from the level varying unit by the level detecting unit, A control step of comparing the output from the level detection means with a reference value of a predetermined magnitude generated in advance and controlling the gain of the level variable means so that they match, Maintaining in the hold means the magnitude of the control signal that controls the level variable means when the output from the level detecting means matches the reference value in the calibration mode; and from the variable level means to the receiving means A step of switching to a use mode for outputting for generating an ultrasonic tomographic image, and a step of controlling the level varying means based on the magnitude of a control signal maintained in the holding means. It is.

  According to the ultrasonic probe according to claim 1, the ultrasonic diagnostic apparatus according to claim 6, and the ultrasonic probe output control method according to claim 7, the level of the output signal is set to a magnitude that matches the reference value. It can be adjusted automatically. As a result, variations in input impedance in the ultrasonic diagnostic apparatus main body can be suppressed, the influence of noise due to a decrease in signal level and distortion of a signal waveform due to an increase in signal level can be reduced, and the S / N ratio is improved. can do. In addition, it is possible to accurately generate an ultrasonic image by suppressing variations in input impedance for each reception channel and making each signal level uniform.

[First Embodiment]
The ultrasonic probe 100 in the present embodiment is connected to the ultrasonic diagnostic apparatus main body 200 via the main body side probe connector 210 and the probe connector 120 in the same manner as the conventional ultrasonic diagnostic apparatus described in the background art shown in FIG. It is used. Further, the ultrasonic probe 100 according to the present embodiment has two modes, a use mode and a calibration mode. Although not shown, the ultrasonic diagnostic apparatus main body 200 has switching means for switching between the use mode and the configuration mode, and the ultrasound probe is switched between the use mode and the configuration mode in accordance with an instruction from the switching means. Works. This switching means is used when there is a possibility that the predetermined input impedance of the ultrasonic diagnostic apparatus body 200 has changed, such as when the power is turned on or when the connection of the ultrasonic probe 100 to a different ultrasonic diagnostic apparatus body 200 is changed. Switch to calibration mode. Furthermore, when the calibration of the ultrasonic probe 100 in the calibration mode is completed, the switching unit switches to the use mode.

  Therefore, output control, which is a feature of the ultrasonic probe 100 according to the present embodiment, will be described. FIG. 1 is a block diagram showing a part of an ultrasonic probe 100 according to this embodiment. FIG. 2 is a diagram showing an outline of an actual physical configuration of the ultrasonic probe according to the present invention. In an actual ultrasonic probe, there are a plurality of vibrators 102 shown in FIG. 1 as shown in FIG. 2, and the same number of level changing means 103 and level detecting means 104 as the vibrators 102 are provided as shown in FIG. ing. Furthermore, the load of the ultrasonic probe 100 according to the present embodiment is determined by the input impedance based on the load 220 of the ultrasonic diagnostic apparatus main body 200. Then, a signal is supplied to the load 220 as a current. In FIG. 2, the transmission / reception selector switch 101, the level variable means 103, the level detection means 104, the reference value generation means 106, and the control means 109 are arranged in the probe connector 120 for miniaturization. It may be arranged outside the probe connector.

(In calibration mode)
The ultrasonic probe 100 according to the present embodiment receives an electrical pulse sent from a transmission / reception circuit 210 provided in the ultrasonic diagnostic apparatus main body 200. Here, although not shown, the transmission / reception circuit 210 includes a transmission unit that transmits a signal to the ultrasonic probe 100 and a reception unit that receives a signal from the ultrasonic probe 100.

  The transmission / reception selector switch 101 includes a switch that can be switched between the transducer 102 side and the ultrasonic diagnostic apparatus 200 side. When a signal is sent from the ultrasonic diagnostic apparatus main body 200, the transmission / reception selector switch 101 switches the switch to the vibrator 102 side and passes the signal through the vibrator 102. Further, when a signal is sent from the level changing means 103, the transmission / reception selector switch 101 switches the switch to the ultrasonic diagnostic apparatus main body 200 side and passes the signal to the ultrasonic diagnostic apparatus main body 200.

  The probe head 110 includes a plurality of transducers 102. The vibrator 102 includes an electrode and a piezoelectric element sandwiched between the electrodes. The transducer 102 converts the received signal into an ultrasonic beam, and transmits the ultrasonic beam toward a dummy subject. Then, the transducer 102 receives the ultrasonic echo reflected by the dummy subject, and converts the received ultrasonic echo into an output signal. Then, the vibrator 102 sends an output signal to the level variable means 103.

  Here, as shown in FIG. 2, an in-head changeover switch 121 and an in-head amplifier 122 are actually arranged in the probe head 110. The intra-head changeover switch 121 passes the signal sent from the transmission / reception changeover switch 101 to the vibrator 102 side. Further, the output signal sent from the vibrator 102 is amplified by the in-head amplifier 122 and passed to the level variable means 103 side by switching of the in-head changeover switch 121.

  In this embodiment, in order to check the operation of the ultrasonic probe, a signal for calibration of the level variable means 103 is generated by scanning a dummy subject using a signal from the ultrasonic diagnostic apparatus main body 200. However, when it is not necessary to check the path on the receiving side, a configuration may be adopted in which a dummy signal equivalent to the output signal from the probe head 110 is directly transmitted to the level varying means 103.

  The level variable means 103 is composed of variable amplification means (variable gain amplifier) as shown in FIG. However, the level variable means 103 is not limited to this configuration, and may be any configuration as long as the gain in the level variable means 103 can be changed, and may be configured by an amplification means and a variable attenuation means. The example of the variable amplifying means shown in FIG. 3 has a configuration in which the bias current IE is changed by changing the voltage by the controller, and the magnitude of the output signal is changed. However, the variable amplifying means is not limited to this configuration, and may be any configuration that can change the magnitude of the output signal. For example, the variable amplification means may be configured to change the magnitude of the output signal by switching resistance. Good.

  The variable amplifying means in the level variable means 103 changes the level of the output signal sent from the probe head 110 based on the change of the gain factor due to the change of the bias current. In the calibration mode, the level varying unit 103 transmits the changed output signal to the level detecting unit 104.

  The level detection means 104 is composed of a diode, for example, and detects the magnitude of the output signal by converting the output signal received from the level variable means 103 into a DC voltage.

  The reference value generation means 106 receives information on an operation mode such as color image display or monochrome image display from the ultrasonic diagnostic apparatus main body 200, and generates a DC voltage having a predetermined magnitude corresponding to the operation mode. To do. Here, in this embodiment, a DC voltage is generated in order to obtain a reference value. However, this is not particularly limited as long as the reference value can be obtained. For example, a value of a predetermined DC voltage magnitude is set. The configuration may be such that it is sent to the comparison means 105.

  The control unit 109 includes a comparison unit 105, a level control unit 107, and a hold unit 108.

  When the comparison means 105 and the level control means 107 are configured to be analog and control is performed, the comparison means 105 takes the difference between the DC voltage output from the level variable means 103 and the DC voltage from the reference value generation means 106, Amplify the difference. Further, when the magnitude of the output signal from the level varying unit 103 matches the reference value, the comparing unit 105 causes the hold unit 108 to maintain the output at that time. Here, the hold means 108 stores an output for each channel. An example of the holding unit 108 is a capacitor when the control unit 109 performs analog control.

  The level control means 107 controls the level variable means 103 with the amplified value so that the magnitude of the output signal from the level variable means 103 matches the magnitude of the DC voltage generated by the reference value generating means 106. For example, when the level of the output signal is lower than the reference value, negative feedback is performed so as to increase the gain of the level varying means 103. In the use mode, the level control unit 107 performs control based on the output maintained in the hold unit 108.

  When the comparison means 105 and the level control means 107 are constituted by a CPU and are controlled digitally, the comparison means 105 is connected to a DC voltage that is an output signal from the level variable means 103 and a DC voltage from the reference value generation means 106. Are A / D converted, and the converted values are compared. Further, when the magnitude of the output signal from the level varying means 103 matches the reference value, the comparing means 105 causes the hold means 108 to maintain the magnitude of the control signal that controls the level varying means 103 at that time. Here, the hold means 108 stores the magnitude of the control signal for each channel. An example of the holding means 108 is a memory when the control means 109 controls the level varying means 103 using a CPU.

  Further, in the present embodiment, the output of the comparison unit 105 when the magnitude of the output signal from the level variable unit 103 matches the reference value is maintained in the hold unit 108. When the magnitude of the output signal coincides with the reference value, the level control means 107 may maintain the magnitude of the control signal controlled by the level variable means 103.

(Use mode)
The ultrasonic probe 100 in the present embodiment receives a signal (electrical pulse) sent from the transmission / reception circuit 210 as in the conventional ultrasonic diagnostic apparatus shown in FIG.

  Similar to the calibration mode, the transmission / reception change-over switch 101 switches the switch to the vibrator 102 side and vibrates when a signal is sent from the ultrasonic diagnostic apparatus main body 200 when a signal is transmitted from the transmission / reception circuit 210. The signal is sent to the child 102 side, and when the signal is received by the transmission / reception circuit 210, the switch is switched to the ultrasonic diagnostic apparatus main body 200 side and the signal sent from the level varying means 103 is sent to the ultrasonic diagnostic apparatus main body 200 side.

  The transducer 102 converts the signal received via the intra-head changeover switch 121 shown in FIG. 2 into an ultrasonic beam, and sends the ultrasonic beam toward the actual subject. Then, the transducer 102 receives the ultrasonic echo reflected by the subject, and converts the received ultrasonic echo into an output signal. Then, the vibrator 102 sends an output signal to the level variable means 103. This output signal is amplified by the in-head amplifying means 122 shown in FIG. 2 and then sent to the level variable means 103 via the in-head changeover switch 121.

  The level control means 107 cuts the line from the comparison means 105 at the time of switching to the use mode.

  The level control means 107 acquires the value of the control signal maintained in the hold means 108. Then, the level control means 107 has the same value as when the magnitude of the output signal from the level variable means 103 coincides with the reference value generated by the reference value generation means 106 based on the acquired value of the control signal. Control.

  The level varying means 103 receives the control signal from the level control means 107, changes the magnitude of the output signal, and outputs it to the transmission / reception circuit 210 provided in the ultrasonic diagnostic apparatus main body 200.

  Further, the ultrasonic diagnostic apparatus to which the ultrasonic probe 100 according to the present embodiment is connected is similar to the conventional ultrasonic diagnostic apparatus in that the output signal transmitted from the ultrasonic probe 100 is amplified by the transmission / reception circuit 210 and the timing is adjusted. After matching, image processing is performed by the signal processing unit 202 and the image processing unit 203, and an ultrasonic tomographic image is displayed on the display unit 205.

  Next, the operation in the configuration mode and the operation in the use mode of the ultrasonic probe according to the present embodiment will be described with reference to FIG. Here, FIG. 4 is a flowchart of the operation of the ultrasonic probe.

  Step S001: The calibration mode and the use mode are switched by the switching means. In the case of the configuration mode, the process proceeds to step S002, and in the case of the use mode, the process proceeds to step S012.

  Step S002: The transducer 102 converts the signal sent from the transmission / reception circuit 210 into an ultrasonic wave and scans the subject dummy.

  Step S003: The vibrator 102 transmits an output signal to the amplification means 103.

  Step S004: The level varying means 103 changes the level of the output signal and transmits it to the level detecting means 104.

  Step S005: The level detection means 104 converts the received output signal into a direct current and outputs it.

  Step S006: The reference value generating means 106 sends a DC voltage having a reference value that matches the mode of the ultrasonic diagnostic apparatus to the comparing means 105.

  Step S007: The comparison unit 105 compares the magnitudes of the output signal of the level detection unit 104 and the reference value. Here, in the case of digital control by the CPU, the output signal of the level detection means 104 and the reference value are A / D converted and then compared.

  Step S008: The level control means 107 determines whether or not the reference value of the output signal matches. If they do not match, the process proceeds to step S009, and if they match, the process proceeds to step S010.

  Step S009: The level control means 107 controls the level variable means 103 based on the comparison between the output signal and the reference value, and proceeds to step S002.

  Step S010: The comparison unit 105 causes the hold unit 108 to maintain the output value when the output signal matches the reference value.

  Step S011: The level control means 107 stops the control.

  Step S012: Based on the value of the control signal maintained in the hold means 108, the level control means 107 performs control so that the output of the level variable means 103 matches the reference value.

  Step S013: The transducer 102 converts the signal sent from the transmission / reception circuit 210 into an ultrasonic beam and scans the actual subject.

  Step S014: The transducer 102 converts the received ultrasonic echo into a signal and outputs it to the level varying means 103.

  Step S015: The level varying means 103 changes the level of the received output signal and transmits it to the transmission / reception circuit 210 via the transmission / reception selector switch 101.

  As described above, the ultrasonic probe 100 according to the present embodiment changes the level varying unit 103 so as to coincide with the reference value. As a result, a change in the level of the output signal due to variations in the input impedance of the ultrasonic diagnostic apparatus main body 200 used as the load 220 can be suppressed, the S / N ratio can be improved, and each signal for each reception channel can be improved. By making the level uniform, an ultrasonic image can be generated with high accuracy.

[Second Embodiment]
The ultrasonic probe according to the present embodiment is controlled when the upper limit of the current supplied to the level variable unit 103 and the upper limit of the temperature near the level variable unit 103 are reached in the ultrasonic probe according to the first embodiment. Is stopped, and the value of the control signal at that time is maintained.

  FIG. 5 is a block diagram showing functions of the ultrasonic probe according to the present embodiment. As shown in FIG. 5, the ultrasonic probe in the present embodiment includes an ammeter 111, a current comparison unit 113, a temperature measurement unit 114, a temperature prediction unit 115, and a temperature comparison unit 116 in addition to the ultrasonic probe according to the first embodiment. It is provided. Since the operation in the use mode is the same as that in the first embodiment, only the case of the calibration mode will be described below.

  Also in the ultrasonic probe according to the present embodiment, based on the signal transmitted from the ultrasonic diagnostic apparatus main body 200 as in the ultrasonic probe of the first embodiment, the transducer 102 scans the dummy of the subject, The ultrasonic echo is converted into a signal, amplified by the in-head amplifying unit 122, and output to the level varying unit 103. Level varying means 103 changes the level of the output signal and outputs it. The level detecting means 104 converts it into a DC voltage and outputs it. In the case of analog control, the comparing means 105 compares the direct current voltage having the reference value generated by the reference value generating means 106 with the output of the level detecting means 104 as it is, and in the case of digital control by the CPU. Compare after A / D conversion. The level control means 107 controls the level variable means 103 so that the output level of the level variable means 103 matches the reference value.

  The power source 112 supplies electricity to the level varying means 103. The thick line shown in FIG. 5 is a power supply line. Here, FIG. 5 schematically shows a part extracted, but actually, as shown in FIG. 2, the power supply 112 supplies current to all of the plurality of level variable means 103.

  The ammeter 111 measures the power supply current supplied to each of the plurality of level variable means 103 from the power supply 112, and adds all the power supply currents supplied to the respective level variable means 103 to obtain the power supply current. The total of all currents sent from is measured.

  The current comparison means 113 stores in advance an upper limit value that can be supplied to all the level variable means 103 based on the current rating of the level variable means 103. Then, the current comparing means 113 receives the measured current value from the current system 111 and determines whether or not the supply current exceeds the stored upper limit value. When the supply current exceeds the upper limit value, the current comparison unit 113 sends a signal to the level control unit 107.

  The temperature measuring unit 114 measures the temperature near the level varying unit 103. Here, FIG. 5 schematically shows a part extracted, but actually, as shown in FIG. 2, the temperature measuring means 114 is arranged in all of the plurality of level variable means 103, respectively. The temperature in the vicinity is being measured. Here, the dotted line shown in FIG. 5 represents that the temperature near the level varying means 103 is measured.

  The temperature predicting means 115 stores the relationship between the statistical temperature increase rate and the temperature after a certain time. Then, the temperature predicting unit 115 receives the temperature information at a predetermined time from the temperature measuring unit 114, calculates the temperature increase rate, and after a certain time from the relationship between the stored temperature increase rate and the temperature for a certain time. The temperature near the level variable means 103 is predicted.

  The temperature comparison unit 116 stores an upper limit value of the temperature of the level variable unit 103 in advance. Then, the temperature comparison unit 1116 compares the temperature predicted by the temperature prediction unit 115 with the upper limit value. The temperature comparison unit 116 sends a signal to the level control unit 107 when the predicted temperature exceeds the upper limit value.

  When the level control means 107 receives a signal from the current comparison means 113 or the temperature comparison means 116, the level control means 107 stops the control of the level variable means 103 and holds the state at the time of the stop. This stop of the control has priority over the control for matching the magnitude of the output of the level varying means 103 with the reference value.

  The level control means 107 causes the hold means 108 to maintain the value of the control signal that was controlling the level variable means 103 when the control was stopped. In the use mode, the level control means 107 controls the level variable means 103 based on the value of the control signal maintained in the hold means 108.

  As described above, in the ultrasonic probe according to the present embodiment, the control can be stopped when the upper limit value of the supply current or the upper limit value of the temperature is exceeded, and the state at that time can be maintained. Thereby, it is possible to avoid a state where power consumption or heat generation becomes excessive by controlling the signal output of the level varying means 103.

Block diagram of the ultrasonic probe according to the first embodiment The figure which shows the outline of the physical structure of the ultrasonic probe which concerns on this invention The figure which shows an example of a level variable means The figure of the flowchart of operation | movement of the ultrasonic probe which concerns on 1st Embodiment. Block diagram of an ultrasonic probe according to the second embodiment The figure for demonstrating the outline | summary of a structure of an ultrasound diagnosing device Schematic diagram of ultrasonic tomogram (B-mode image)

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Ultrasonic probe 101 Transmission / reception changeover switch 102 Vibrator 103 Level variable means 104 Level detection means 105 Comparison means 106 Reference value generation means 107 Level control means 108 Hold means 109 Control means 110 Probe head 111 Ammeter 112 Power supply 113 Current comparison means 114 Temperature measurement means 115 Temperature prediction means 116 Temperature comparison means 120 Probe connector 121 In-head changeover switch 122 In-head amplifier 200 Ultrasonic diagnostic apparatus main body 201 Ultrasonic diagnostic apparatus side connector 202 Signal processing section 203 Image processing section 204 Control circuit 205 Display section 206 Operation Panel 210 Transmission / Reception Circuit 211 Transmission Delay Circuit 212 Pulser 213 Preamplifier 214 Transmission / Reception Switch 215 Reception Delay Addition Circuit 220 Load

Claims (6)

An ultrasonic probe comprising a plurality of transducers for receiving a signal from a transmitting means provided on the ultrasonic diagnostic apparatus main body side, transmitting an ultrasonic beam to the subject, and receiving ultrasonic echoes reflected by the subject Because
Corresponding to the vibrator,
Level changing means for changing the magnitude of the output signal from the vibrator and supplying it to the receiving means provided on the ultrasonic diagnostic apparatus main body side;
Level detecting means for detecting the magnitude of an output signal from the level varying means;
A reference value generating means for generating a reference value of a predetermined size;
An ultrasonic probe comprising: a control unit that compares an output from the level detection unit with the reference value and controls a gain of the level variable unit so that they match. A current comparing means for comparing a total of power supply currents supplied to each of the plurality of level variable means and an upper limit value stored in advance;
The control means includes
The ultrasonic probe according to claim 1, wherein the control is stopped when the supplied current reaches the upper limit value. Temperature measuring means for measuring the temperature near the level variable means;
Temperature predicting means for predicting a temperature rise from the measured temperature;
A temperature comparison means for comparing the upper limit value of the temperature stored in advance with the predicted temperature;
The control means includes
The ultrasonic probe according to claim 1 or 2, wherein the control is stopped when the temperature in the vicinity of the level varying means reaches the upper limit value of the temperature.   The ultrasonic probe according to claim 1, wherein the load of the level varying unit is determined by an input impedance of the ultrasonic diagnostic apparatus main body. An ultrasonic probe;
Transmission / reception means for scanning and receiving a subject with ultrasonic waves via the ultrasonic probe;
An ultrasonic diagnostic apparatus comprising: an image generation unit that generates an ultrasonic image based on data received by the transmission / reception unit and displays the image on a display unit;
The ultrasonic probe is
A plurality of transducers for receiving a signal from a transmission means provided on the ultrasonic diagnostic apparatus main body side, sending an ultrasonic beam to the subject, and receiving ultrasonic echoes reflected by the subject;
Corresponding to the vibrator,
Level varying means for varying the magnitude of the output signal from the transducer and supplying the receiving means provided on the ultrasonic diagnostic apparatus main body side;
Level detecting means for detecting the magnitude of an output signal from the level varying means;
A reference value generating means for generating a reference value of a predetermined size;
An ultrasonic diagnostic apparatus comprising: a control unit that compares an output from the level detection unit with the reference value and controls a gain of the level variable unit so that they match. Switching to a calibration mode for calibrating the output of the variable level means;
Receiving a signal from a transmission means provided on the ultrasonic diagnostic apparatus main body side and transmitting an ultrasonic beam from a plurality of transducers to a subject;
Receiving ultrasonic echoes reflected by the subject with the plurality of transducers;
A level changing step of changing the magnitude of the output signal from the transducer by the level variable means and supplying the level to the receiving means provided on the ultrasonic diagnostic apparatus main body side;
A level detection step of detecting the magnitude of the output signal from the level variable means by the level detection means;
A control step of comparing the output from the level detection means and a reference value of a predetermined magnitude generated in advance and controlling the gain of the level variable means so that they match,
Maintaining the magnitude of the control signal controlling the level variable means in the hold means when the output from the level detection means matches the reference value in the calibration mode;
Switching from the configuration mode to a use mode for performing output for creating an ultrasonic tomographic image;
An ultrasonic probe output control method comprising: controlling the level varying means based on the magnitude of a control signal maintained in the holding means.

Images