CN202654158U

CN202654158U - Digital pulse-type ultrasonic transmitting device used for fetal monitor

Info

Publication number: CN202654158U
Application number: CN 201220097111
Authority: CN
Inventors: 范世忠
Original assignee: TAI'AN MEDI MEDICAL ELECTRONIC CO Ltd
Current assignee: TAI'AN MEDI MEDICAL ELECTRONIC CO Ltd
Priority date: 2012-03-15
Filing date: 2012-03-15
Publication date: 2013-01-09
Anticipated expiration: 2022-03-15

Abstract

The utility model discloses a digital pulse-type ultrasonic transmitting device used for a fetal monitor and relates to the field of medical apparatus and instruments. The digital pulse-type ultrasonic transmitting device used for the fetal monitor consists of an ultrasonic probe and an ultrasonic transmitting circuit which are connected with each other. According to the digital pulse-type ultrasonic transmitting device used for the fetal monitor, a plurality of wafers which integrates a transmitting function and a receiving function and is 1.0MHz in transmitting frequency are evenly arranged on the radiating surface of the probe; an ultrasonic transmitting acoustic beam is wide, and cannot be easily influenced by fetal movements and uterine contraction when a signal of a fetal heart is detected during a monitoring process, and thereby, a monitoring result is more accurate and reliable. A transmitting electric excitation square signal of which the transmitting frequency is 1.0MHz is generated by the transmitting circuit by utilizing a complex programmable logic device (CPLD) digital circuit, and is coupled to the ultrasonic probe through a resonance amplifying circuit to generate an ultrasonic wave of which the transmitting frequency is 1.0MHz. The digital pulse-type ultrasonic transmitting device used for the fetal monitor has the advantages that the transmitting frequency is low; attenuation is low during an ultrasonic propagation process; the reflection echo is strong; the sensitivity is high; the noise is low; the anti-jamming capability is high; and the performance is stable and reliable.

Description

The digital pulse type ultrasonic transmitter that is used for fetal monitor

Technical field

This utility model relates to medical instruments field, specifically a kind of digital pulse type ultrasonic transmitter for fetal monitor.

Background technology

At present, most of fetal monitor adopts 2.0MHz～2.5MHz continuous ultrasound doppler Method to pick up fetal heart rate signal, its structure of ultrasonic is middle wafer, diameter 2cm, the emission ultrasound wave, the width of the ultrasound beamformer of its emission is 2～3cm, this is the catching range of fetal rhythm namely, 6 little wafers receive ultrasound wave on every side, and the fetal heart rate signal that picks up is processed rear demonstration or printing.The ultrasound emission frequency that most of monitor adopts is at 2.0MHz～2.5MHz, frequency is higher, because the decay when ultrasound wave is propagated in human body is directly proportional with hyperacoustic frequency, so during the ultrasonic propagation of some strength, upper frequency, have following problem: if the distance of 1. propagating is identical, frequency is higher, it is larger to decay, reflection echo is more weak, and sensitivity is lower, more is not easy to detect fetal heart rate signal; 2. frequency is higher, and it is larger to decay, and the distance that ultrasound wave is effectively propagated is shorter.

In addition, most of monitor adopts the analog signal generator that is comprised of inductance, electric capacity, resistance, integrated operational amplifier circuit as radiating circuit, produces 2.0MHz～2.5MHz ultrasonic exciting signal and is transmitted on the ultrasonic probe.As everyone knows, after circuit working a period of time (generally more than half a year), because small variation can occur in the parameter of inductance, electric capacity, resistance, cause the frequency of the electric excitation signal of this analog signal generator generation to change, no longer equal the natural resonance frequency of ultrasonic probe (transducer that is comprised of piezoelectric), ultrasonic probe no longer is operated in resonance point, and emission effciency reduces, the emission pumping signal weakens sensitivity; During receiving demodulation, a difference frequency signal can occur, noise occur, and be subjected to easily the interference of other signals.

To sum up, be applied at present the following shortcoming of ultrasonic transmitter existence of fetal monitor:

1) the ultrasonic probe acoustic beam is thin, and the fetal rhythm catching range is narrow, is subject to the impact of fetal movement and uterine contraction, and fetal heart rate signal is lost or indeterminacy when causing fetal movement, uterine contraction.

2) the radiating circuit ultrasonic frequency is high, and it is large to decay in communication process, and a little less than the reflection echo, sensitivity is low, is unfavorable for clinically pregnant anemia of pregnant woman, fat anemia of pregnant woman or occipitoposterior position anemia of pregnant woman's monitoring.

3) the radiating circuit ultrasonic frequency is easily drifted about, and noise is large, poor anti jamming capability.

4) whole discharger stability is poor, noise will occur after general machine uses half a year, and sensitivity is difficult to capture fetal rhythm.

Summary of the invention

For solving the technical problem of above-mentioned existence, this utility model provides a kind of digital pulse type ultrasonic transmitter for fetal monitor, ultrasonic probe emission acoustic beam is wide, the Digital Square-Wave that radiating circuit utilizes the CPLD digital circuit to produce 1.0MHz transmits, the sinusoidal wave emission of the pulsed electric excitation signal that forms 1.0MHz through oscillator amplifier circuit is coupled to ultrasonic probe, launch the ultrasound wave of 1.0MHz, tranmitting frequency is low, noise is little, capacity of resisting disturbance is strong, stable and reliable for performance, in the monitoring process detection of fetal heart rate signal is not vulnerable to the impact of fetal movement and uterine contraction, the monitoring result is more accurately and reliably.

For achieving the above object, the technical solution adopted in the utility model is as follows:

The digital pulse type ultrasonic transmitter that is used for fetal monitor, by interconnective ultrasonic probe and ultrasound emission the electric circuit constitute, described ultrasonic probe includes a plurality of wafers 1 that integrate emission, reception signal that are arranged on the probe radiating surface 2, and the tranmitting frequency of described wafer 1 is 1.0MHz; Described ultrasound emission circuit is comprised of digital integrated electronic circuit module CPLD and radiating circuit, the Digital Square-Wave that described digital integrated electronic circuit module CPLD produces 1.0 MHz transmits, described radiating circuit is oscillator amplifier circuit and peripheral circuit thereof, and described oscillator amplifier circuit is comprised of audion Q1, inductance L 2, capacitor C 13, capacitor C 14 and transformator T1.

The wafer of described ultrasonic probe is 8-12.

The diameter of the wafer of described ultrasonic probe is identical.

Inductance L 2 is connected between audion Q1 base stage and the emitter-base bandgap grading in the described resonance circuit, an end ground connection after capacitor C 13, capacitor C 14, the transformator T1 parallel connection, the other end is connected with the colelctor electrode of audion Q1 by parallel diode D1, and the secondary coil of transformator T1 is connected with wafer 1 on the ultrasonic probe

Resistance R 3 is connected in series with capacitor C 10 in the peripheral circuit of described radiating circuit, the base stage of another termination audion Q1 of resistance R 3, the output signal U STR of another termination digital integrated electronic circuit module CPLD of capacitor C 10 connects, ground connection after capacitor C 11, the capacitor C E10 parallel connection, another termination inductance L 2 and inductance L, inductance L and capacitor C 12 meet power supply VCC simultaneously, capacitor C 12 other end ground connection.

The beneficial effects of the utility model are as follows:

1) ultrasonic probe adopts a plurality of wafers to be evenly distributed on the structure of probe radiating surface, tranmitting frequency is 1.0MHz, all wafers all participates in emission during emission, all wafers all transfers reception to during reception, so that its emission beam width is 7～8cm, thereby increased the fetal rhythm catching range, the detection on fetal heart rate signal in the monitoring process just is difficult for being subjected to fetal movement and uterine contraction to affect;

2) radiating circuit utilizes the Digital Square-Wave of CPLD digital circuit generation 1.0MHz to transmit, the sinusoidal wave emission of the pulsed electric excitation signal that forms 1.0MHz through oscillator amplifier circuit is coupled to ultrasonic probe, launch the ultrasound wave of 1.0MHz, emission, reception signal adopt the DSP digital technology to process, capacity of resisting disturbance is strong, and noise is low;

3) adopt 1.0MHz ultrasound emission frequency, lower than traditional ultrasound emission frequency, it is little to decay in the transonic process, and reflection echo is strong, and is highly sensitive, and fetal rhythm catches easily, and the distance of propagating is farther, is more suitable for fat anemia of pregnant woman and occipitoposterior position anemia of pregnant woman monitoring;

4) whole discharger stable performance, reliable in quality.

Description of drawings

Fig. 1 is the structural representation of this utility model ultrasonic probe;

Fig. 2 is this utility model digit pulse ultrasound emission circuit connection diagram;

The specific embodiment:

Below in conjunction with the drawings and specific embodiments this utility model is described in detail:

Be a specific embodiment of the present utility model as depicted in figs. 1 and 2.

As shown in Figure 1, ultrasonic probe includes 8-12 and evenly is arranged at wafer 1 on the probe radiating surface 2, and this wafer 1 integrates emission, receives semiotic function, and diameter is identical, is 12mm, and the ultrasound emission frequency is 1.0MHz.

As shown in Figure 2, the ultrasound emission circuit is comprised of digital integrated electronic circuit module CPLD and radiating circuit, radiating circuit is oscillator amplifier circuit and peripheral circuit thereof, inductance L 2 is connected between the base stage and emitter-base bandgap grading of audion Q1 in the resonance circuit, an end ground connection after capacitor C 13, capacitor C 14, the transformator T1 parallel connection, the other end is connected with audion Q1 colelctor electrode by parallel diode D1, and the secondary coil of transformator T1 is connected with wafer 1 on the ultrasonic probe.

Resistance R 3 is connected in series with capacitor C 10 in the peripheral circuit of radiating circuit, the base stage of another termination audion Q1 of resistance R 3, the output signal U STR of another termination digital integrated electronic circuit module CPLD of capacitor C 10 connects, ground connection after capacitor C 11, the capacitor C E10 parallel connection, another termination inductance L 2 and inductance L, inductance L and capacitor C 12 meet power supply VCC simultaneously, capacitor C 12 other end ground connection.

During this utility model work, the Digital Square-Wave of the 1.0MHz that is produced by the digital integrated electronic circuit module CPLD circuit USTR that transmits, through the oscillator amplifier circuit that is comprised of audion Q1, inductance L 2, capacitor C 13, capacitor C 14 and transformator T1, its harmonic component is suppressed, and first-harmonic is exaggerated, produce the electrical excitation pulse signal, be 100 μ s launch time,, time of reception is 400 μ s,, Vp-p=10V.This emission electrical excitation pulse signal process transformator T1 is coupled to and encourages the ultrasonic probe tranmitting frequency on the ultrasonic probe is the ultrasound wave of 1.0MHz.

Transformator T1 will launch the electrical excitation pulse signal coupling to ultrasonic probe, play the effect of impedance matching, utilize simultaneously transformator T1 secondary inductance amount and ultrasonic probe resonance on 1.0MHz, so that emission effciency is the highest, the ultrasound wave of emission is the strongest, and sensitivity is the highest.

Claims

1. digital pulse type ultrasonic transmitter that is used for fetal monitor, it is characterized in that, by interconnective ultrasonic probe and ultrasound emission the electric circuit constitute, described ultrasonic probe includes a plurality of wafers (1) that integrate emission, reception signal that are arranged on the probe radiating surface (2), and the tranmitting frequency of described wafer (1) is 1.0MHz; Described ultrasound emission circuit is comprised of digital integrated electronic circuit module (CPLD) and radiating circuit, the Digital Square-Wave that described digital integrated electronic circuit module (CPLD) produces 1.0 MHz transmits, described radiating circuit is oscillator amplifier circuit and peripheral circuit thereof, and described oscillator amplifier circuit is comprised of audion (Q1), inductance (L2), electric capacity (C13), electric capacity (C14) and transformator (T1).

2. the digital pulse type ultrasonic transmitter for fetal monitor according to claim 1 is characterized in that, the wafer of described ultrasonic probe (1) is 8-12.

3. the digital pulse type ultrasonic transmitter for fetal monitor according to claim 1 and 2 is characterized in that, the diameter of the wafer of described ultrasonic probe (1) is identical.

4. the digital pulse type ultrasonic transmitter for fetal monitor according to claim 1, it is characterized in that, inductance in the described resonance circuit (L2) is connected between audion (Q1) base stage and the emitter-base bandgap grading, electric capacity (C13), electric capacity (C14), transformator (T1) rear end ground connection in parallel, the other end is connected with the colelctor electrode of audion (Q1) by parallel diode (D1), and the secondary coil of transformator (T1) is connected with wafer (1) on the ultrasonic probe.

5. the digital pulse type ultrasonic transmitter for fetal monitor according to claim 1, it is characterized in that, resistance in the peripheral circuit of described radiating circuit (R3) is connected in series with electric capacity (C10), the base stage of another termination audion (Q1) of resistance (R3), the output signal (USTR) of another termination digital integrated electronic circuit module (CPLD) of electric capacity (C10) connects, electric capacity (C11), ground connection after electric capacity (CE10) is in parallel, another termination inductance (L2) and inductance (L), inductance (L) and electric capacity (C12) connect power supply (VCC) simultaneously, electric capacity (C12) other end ground connection.