CN2227843Y

CN2227843Y - X-ray digital mAs meter

Info

Publication number: CN2227843Y
Application number: CN 94245175
Authority: CN
Inventors: 柯坚
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-11-16
Filing date: 1994-11-15
Publication date: 1996-05-22
Anticipated expiration: 2004-11-15

Abstract

The utility model discloses an X-ray digital mas meter, which is used for measuring the X-ray mas value and the current value of an X-ray tube. Mainly a constant-current or constant-voltage charging circuit is additionally arranged through a switch between a rectification circuit and an integrator computing unit in the original X-ray digital mas meter, on the basis of keeping the measurement function of the original X-ray digital mas meter, the measurement and the result display of the X-ray exposure time are added, and the ratio between the X-ray mas value and the time value namely the current of the X-ray tube is measured. The utility model has the advantages of simple circuit, small size and less power consumption and has definite reality significance to the quality control of the production and the running of the X-ray machine and the assurance of the installation and debugging of the X-ray machine and the detection and maintenance of faults.

Description

X line numeral mAs/stopwatch

The utility model relates to a kind of X line numeral mAs/stopwatch that is used for measured X line mAs value and x-ray tube current value thereof.

X line mAs value all is to record by an X line numeral milliampere stopwatch in the prior art, this X line numeral milliampere stopwatch border in fact is a charge counter, it is by rectification circuit, integrator computing unit, the frequency conversion type oscillator is formed, " virtual earth " and this end input current according to integral operation circuit inverting input are zero hypothesis, obtain this integrator output voltage and be proportional to the result of input voltage time integral, input voltage is gone into " virtual earth " and is produced input current through a resistance, this electric current equates with the electric current that produces the integrating capacitor charging charge, whenever fill a unit charge and can make controlled frequency conversion type oscillator vibration once, and integrating capacitor is discharged to previous status, the product that just can obtain input current and time is counted in output to oscillator, thereby obtains the metering of X line exposing amount.Prior art is that control is opened and closed clock gate, and the gate clock pulse count is recorded the X line exposing time with edge, back before the current impulse of x-ray tube current pulse or the generation of X ray Sensitive Apparatus to the measurement of X line exposing time.More than two kinds of prior aries be difficult to form the mAs/stopwatch of unified technology.The instrument of both unifications often circuit is comparatively complicated, and power consumption is more, and mains-supplied volume commonly used is bigger.

But the purpose of this utility model is to provide a kind of both measured X line mAs value for the deficiency that solves above technology, can directly record the X line exposing time again, and X line simple in structure numeral mAs/stopwatch.

In order to achieve the above object, X line numeral mAs/stopwatch that the utility model is designed, mainly form by housing, digital circuit, signal input part, circuitry for signal measurement, circuitry for signal measurement mainly is made up of rectification circuit, integrator computing unit, frequency conversion type oscillator, between rectification circuit and integrator computing unit, insert charging circuit by change-over switch, wherein but charging circuit can be the constant-current charge circuit that transfer in the school, establishes constant current source in promptly; But also can be the constant voltage charging circuit that transfer in the school, establish constant pressure source in promptly, make constant electric current only relevant with the time to its integral result of definite value integrating capacitor charging back.

Because of causing instrument, the excessive misoperation of input current damages during for fear of work when surveying, input end at charging circuit is provided with stabilivolt, in order to reduce the temperature effect in the instrument measurement, improve measuring accuracy, in charging circuit, temperature-compensation circuit can be set.

This X line numeral mAs/stopwatch, after inserting charging circuit by change-over switch between rectification circuit in former X line numeral milliampere stopwatch and the integrator computing unit, make the main circuit of timing measuring and the main circuit of mAs value measurement be combined into same main circuit, therefore reached on same main circuit by the simple purpose of switching realization X line mAs value and the timing measuring of X line exposing time thereof.

This X line numeral mAs/stopwatch, circuit is simple, and volume is little, and temperature coefficient is little, the power consumptive province, available powered battery is convenient to former X line milliampere stopwatch is reequiped simultaneously.

Fig. 1 is X line mAs/stopwatch synoptic diagram;

Fig. 2 is an X line milliampere stopwatch circuitry for signal measurement;

Fig. 3 is the constant-current charge circuit;

Fig. 4 is a constant voltage charging circuit.

The utility model will be further described in conjunction with the accompanying drawings below by embodiment.

The described X line of this example mAs/stopwatch as shown in Figure 1, mainly form by housing 1, digital circuit 2, signal input part 3, circuitry for signal measurement 4, circuitry for signal measurement 4 mainly is made up of rectification circuit 5, integrator computing unit 6, frequency conversion type oscillator 7 as shown in Figure 2, the constant-current charge circuit 9 that inserts as shown in Figure 3 by change-over switch 8 between 3 of a, b between rectification circuit 5 and the integrator computing unit 6, c is provided with pull-up resistor R at the input end of constant-current charge circuit 9 ₁With stabilivolt W ₁, output terminal is a constant current source 10, constant current source 10 passes through R ₄Transfer and R in the school ₂, R ₃Obtain temperature compensation.

Between a, b between rectification circuit 5 and the integrator computing unit 6, c, also can insert as shown in Figure 4 constant voltage charging circuit 11 at 3, be provided with stabilivolt W at the input end of constant voltage charging circuit 11 by change-over switch 8 ₂, its output terminal is provided with stabilivolt W ₃With Low ESR voltage divider R ₈, x-ray tube current partly flows through stabilivolt W ₃Form voltage stabilizing, again through adjustable Low ESR voltage divider R ₈Reach input resistance former integrating capacitor is charged, like this, can under the x-ray tube current condition of certain limit, obtain the duration of charging counting, adjustable voltage divider R ₈The output size can the school transfer the meter reading coefficient, make ten integral multiples of its each counting for millisecond, as 0.01 second, thereby finish the amplification of timing measuring.X line mAs/stopwatch that present embodiment provided can realize by increase charging circuit on 07-472 type numeral milliampere stopwatch, and scope is set between 0.01 second to 19.99 seconds will survey according to the needs of X line machine the time.

Claims

1, a kind of X line mAs/stopwatch, it comprises rectification circuit, integrator computing unit and frequency conversion type oscillator, it is characterized in that inserting charging circuit by change-over switch between rectification circuit and integrator computing unit.

2, X line mAs/stopwatch according to claim 1, but it is characterized in that described charging circuit is the constant-current charge circuit that transfer in the school.

3, X line mAs/stopwatch according to claim 1, but it is characterized in that described charging circuit is the constant voltage charging circuit that transfer in the school.

4, according to claim 1 or 2 or 3 described X line mAs/stopwatches, it is characterized in that described charging circuit is provided with stabilivolt at input end.

5, according to claim 1 or 2 or 3 described X line mAs/stopwatches, it is characterized in that being provided with temperature-compensation circuit in the described charging circuit.

6, X line mAs/stopwatch according to claim 4 is characterized in that being provided with temperature-compensation circuit in the described charging circuit.