JPS5841640B2 - X-ray device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a tetrode vacuum tube to control the 1" X-ray tube 7Z voltage, and is capable of controlling the amount of exposed X-rays with high response speed and low power.・'Xm device that can be used for two or more times.

When performing X-ray fluoroscopy or X-ray cinegraphy of a subject using an X-ray device, move the fluoroscopy/photography part of the subject to obtain X-ray images from various angles. If the thing is 1~, then j~ is A-, ``-, Nawaramata.

In this case, the amount of X-rays to be exposed is controlled according to the thickness of each part of the subject, and for example, in a fluoroscopic display device, cooling is required to keep the output brightness of the X-ray multiplier tube constant. Sa11,
7ζ).

This kind of control operation is commonly referred to as A B (: (dispatch brightness adjustment), and several methods have been put into practical use.
The typical spring control method is χ, as shown below.

(1) High RF generation) The primary voltage of the lance is a single-turn sliding transformer. ．． ．．
How to control the voltage between X-ray tubes.

(2) A method of automatically controlling the filament current of the X-ray tube and controlling the current of each tube.

But ly'r mentioned above? , = 2 The method of T2) has the drawback of slow response speed.

jNfJ et al., the above method (1)//) slows down the response speed of the...53, and method (2)-c changes the Neuranon I current? [However, the filament heat does not follow this current change and the time is delayed j′! Furthermore, the above two -h methods have the disadvantage that they also require a large direct force to limit f-.

-I'l: The present invention i'LL was made in view of the circumstances, and it is 7b.
~'-(Only two are used)-I, -Tetrode vacuum tube (T
ETIiou) E (hereinafter referred to as tetrode) is used for control by using this tetrode as a switch for X-ray exposure and an element for controlling the sequence of X-rays. Ll, effective ABC operation 4, which speeds up the response speed and enables low power control... 1-The purpose is to provide an X-ray device that can do the following.

An embodiment of the present invention f/) will be described below with reference to Figure dnj.

FIG. 1 shows the exposure fJ1 stroke-11 of the shortened structure of the present invention. Overview of the control unit ζ・;jr;e The high voltage generator of ', is not shown in the figure, but is given to the primary winding of the three AI AC power supply or -f'-, and the AC power supply voltage is given to the primary winding of the high voltage generating transformer 2, this 1
! (High voltage rectifier r that rectifies the output of voltage generator 1 transformer 7 transformer 2)
18. I, I, j) 3. Consists of a tetrode control unit F 49 b, detailed II will be described later;) t1゛skewer 1
·reactor.

Here, Tetro-de control, code, -tsul'''49!1
'l', which have the same configuration and are inserted in series on the X-ray tube facing side and cathode side, respectively, and have an electrical withstand voltage of 7 and 8 and 9, respectively. Let's have it, τi, °−r"2. two).

In addition, 7 receives an X-ray exposure signal: a tie-1 circuit that controls the exposure time according to the thickness of the subject, IH', and the tube controller of the X-ray tube 6; Bias control circuits 1.1, 4 and 5 of the buttocode control unit 1.1 for
12 is the above-mentioned Buto ``7.
An example of a filament power supply is Bear θ; 11 Bunryu i-00
This is the input terminal of the Vi source.

. On the other hand, Tetro-de control j-knits 4 and 5 are shown in Figure 2.
The cafeteria is configured as shown, and it is described! -2, the units 4 and 5 have the same K configuration.
Therefore, the details will be explained using the same symbols as f'1 and 4 in the same part.

The output of the timer circuit T is introduced into the input terminals A and BE, and the output of the timer circuit 4 is connected to the high resistance lance I.
Adjust as appropriate from IK.

In order to improve the responsiveness to the X-ray exposure signal, it is appropriate to use a transformer made of a Ferrai l-core for the two-high needle lance lance 112).

Therefore, the secondary voltage of the transformer 11 or the high wave rectifier circuit 12
rectified by j121, resistor 135. 1. Through a smoothing circuit consisting of a 27-denser 14. '? 'Ni-switching to--
> Applied to the base of the resistor 15 as a base bias voltage.

In addition, input terminal C and D'Kit are connected to the above 1. A constant voltage, for example 100V AC, is applied at all times, and this voltage is passed through a high-voltage transformer 16, ``low)]-...
The primary winding υ of the transformer 17 is supplied.

The secondary winding of any low voltage transformer IT is the first, grid...
-1′ ground supply winding 18 and filament power supply winding 1
9 etc., and the secondary electric currents 1 to 1 generated in the winding 18 are
After rectifying the rectifier 41' with the full-wave rectifier circuit 20, the resistor 41.7
It is converted into a direct current by a smoothing circuit consisting of a funnel 21, and the positive side of the diameter is connected to the cup of Tetrode 8, and the negative side is 'ip'.
22 to the first grid needle of said tetrode 8 through thread 1. 1. The positive side of the smoothing circuit (1)
It is also connected to the gate 1/coupler of the transistor 15, and serves as the power supply voltage for the transistor.

The winding 19 is directly connected to the Tetro--Dolo cathode, and serves as a power source for heating the filler and ment.

Further 1. -72 The input terminals E and FK receive the output voltage of the bias control circuit 10 by -1, and after this output voltage is appropriately adjusted by the high voltage I panning 23, the low voltage transformer,
Step 24 lowers the pressure l'1. Rectified by the full wave rectifier circuit 25
'1 is converted to DC by a smoothing circuit consisting of a resistor 42 and a capacitor 2G, and the positive side of the DC voltage obtained here is 11.
- A force connected to the negative side or cathode of the second grid of node 8.

This (i3J, U ητ1~ controls the tetrode inserted in series on the evening and get sides of the X-ray tube G by ';-t4, controls i'Sre1, control 1 A tetrode 8 inserted in series on the cathode side of the tube 60 is controlled by the unit 5.

Therefore, if there is no lily exposure signal at the timer circuit at the terminals A and H, the base switch τ of the transistor 15 will have a bias bias of −4°C14·Z, so the transistor 15 IFyA>: ON state VX is present 2, so that (DC voltage is generated across the capacitor 21 through the resistor 22,
"-C" 95 is applied between the first grids, and the first grids are biased in the negative direction by the cathode .eta.L.

This first grid W is applied to the 2') angle, and the 4 pressure is applied to the 4) B)
・By setting the voltages 8 and 9 in advance to a sufficient voltage for I-MEF and Z), in this state, the butrode 8.9 becomes non-conductive, and the X-ray tube 6 is No high voltage is applied to the high voltage rectifier circuit 3.

Next, an X-ray exposure signal is applied, and when the timer circuit T applies the AC voltage to the terminals A and BK for a predetermined time, the AC voltage is rectified and applied to the base of the transistor 15. Base bias is applied to transistor 15
turns on.

Therefore, the voltage between the cathodes of the buttrodes 8 and 9 and the first grid becomes approximately OV, and the tetrodes 8 and 9 become conductive.

By the way, the terminals E and FK are connected to the bias control circuit 10.
A DC voltage obtained by rectifying this AC voltage is applied as a bias voltage between the cathode and the second grid.

Therefore, depending on the voltage value applied to this second grid:
This will control the voltage between the can-dos and the plates of Tetro-dodes 8 and 9.

Now, if the circuit shown in No. 24ic is rewritten as equal reduction 7711, it becomes VX as shown in FIG.

That is, the high voltage transformer 119 and rectifier circuit 12 shown in FIG.
, a switching circuit consisting of a resistor 13, a capacitor 14, and a transistor 15 is a switch S1V: , a high voltage transformer 16, a low voltage transformer 17, and their secondary windings 18, 1
9. The first grid bias circuit consisting of a rectifier circuit 20, a resistor 41, and a capacitor 21 is EgIK, and further includes a high voltage transformer 23, a low voltage transformer 24, a rectifier circuit 25, and a resistor 42.
, the second grid bias circuit consisting of the capacitor 26 corresponds to Eg:i[, respectively, and when the X-ray exposure signal from the timer circuit 7 is given, the switch S1 is closed and the switch S1 is closed. 8.9 becomes conductive, and its internal voltage drop EP is determined by the voltage value of the power source Eg2.

Therefore, if the tube voltage of the X-ray tube 6 is represented by {circumflex over (2)}, the rectified output voltage of the high-voltage rectifier circuit 3 is set as EHT, and Jj can be obtained by the following formula.

On the other hand, the pre-t current Ip of the tetrodes 8 and 9 becomes the tube current of the tt X-ray tube 6.

By the way, 1. In the X-ray WK, the relationship between the tube current Ip and the filament current If is generally as shown in FIG.

That is, as is clear from the IpIf characteristics of the X-ray tube shown in FIG. 4, the tube current Hp is largely dependent on the filament current IfK1.
In fluoroscopy, the range of tube current is usually 1.00 m.
Since it is mostly below A, in this range the tube current I l-) does not depend on the tube voltage VX, and if the filament current If is kept constant, the X-ray tube 6 will have a tetrode 8,
9 can be regarded as a constant current load.

On the other hand, as is well known, due to the characteristics of a tetrode, if the plate current (p1) and the first grid voltage (Egl) are constant, the plate voltage, that is, the internal voltage drop Ep, depends on the second grid voltage (Eg2). By changing the second grid voltage Eg2, it is possible to control the internal voltage drop Ep of the tetrode, and as a result, as is clear from equation (1) above, the tube-to-line voltage Vx remains constant at a constant tube current Ip.
By controlling this, the amount of X-rays emitted from the X-ray tube 6 can be controlled.

That is, due to the action of the first grid of tetrodes 8 and 9, the action of the second grid of V (mi, zo) makes it possible to perform the "shark motion" of X-ray exposure. X-ray tube, +EE'y Controls the
What you can do is η72.

The timer circuit 71t3 is constructed as shown in FIG. 3.

In other words, if the input terminal - 了 (÷ 1 exposure to Shingetsu - h, is obtained,
The monostable multi-vibrator 27 is driven by using the exposure signal of each as a trigger signal. At the time of exposure, the exposure time corresponding to the diagnostic area is set.1.The pulse setting device 28 generates a pulse signal with a controlled output pulse width.1. -1 badass signal is applied to the gate circuit 2, and while the pulse signal is present, the [・circuit 29 is 5FI The circuit 29 has a 1F string wave oscillation jEjl 'y,
An output of f53 is given, and the gate is open. L1 is increased by 1" as appropriate; IJ is turned out; J) The input terminals A and BE of the control 61 t-4 and t-5 are set by dividing the lance 32.

Next, 1: Description 1-2J: Using the two-irradiation control unit, this configuration j ~
An example of the overall configuration of an X-ray equipment based on the ABC method B is shown in Figure G. The generator 1 operates and X-rays are emitted from the X-ray tube 6 ] 9.' Then, these X-rays pass through the subject 33 1-7 and the transmitted X-rays pass through the X-ray fluorescence multiplier tube. 34; :The image is optically distributed Fuji 35η5(', j-, Lithia,
・Image is distributed to B iJ% U 36 and cine camera 31.1. 8 fluoroscopic images were performed respectively (7.2).

-・Power before light)! ``In the distribution mode 35, for example, a photomultiplier tube 21, etc., is provided with a brightness detection a38, and the output brightness of the X-ray fluorescence multiplier tube 34 is Detection;
A detection signal of 7-brightness detection 2;÷38 is applied to the bias control circuit 10 by 4'ff1a.

3 and the bias control circuit '10? , τ(5, approximately 1-1 is set 1, and the appropriate brightness 'f5.l?2-corresponding reference voltage FEEr is given as 7, and the reference voltage pf of 8.6(-) is set to Supplement the brightness detection signal qva +E
Next, the output signal from the bias control circuit 10 is input to the input terminal E of the control units 1-4 and 5.

-tj is applied to control the second grid voltage of bootloads 8, 9. ,
・The X-ray tube G and the tube voltage are varied to control the irradiated X-ray dose and the luminance detection signal is set to the reference voltage E r
III Follow.

, a 1.6W vibration control system will be constructed.

Therefore, the thickness of 33 subjects (sr changes L・, i
-2) Even if the X-ray intensity increases (the output brightness of the sound tube 34 is always kept at an appropriate value), this will occur.

As described above, the present invention 1L controls the first grid of the tetrode connected in series with the LJ X-ray tube, thereby making it possible to control the exposure of the X-ray tube. Along with
4) The beam pressure applied to the second grid of the tetrode is controlled, the X-ray voltage is controlled, and the exposed X-ray dose is controlled. The general world has changed dramatically, and it has become possible to control the X-ray dose with low power. An X-ray device that can do...ξ is now available.

[Brief explanation of the drawing]

11ffl&' text A block diagram showing one implementation of the present invention J Figures 2 and 5 are detailed configuration diagrams of the main parts of the same embodiment, Figure 3 is an equivalent circuit diagram of Figure 2, and Figure 4 is an X-ray diagram. Ip1f special 1st land 1st land map of the pipe, Figure 6 is the entire FIJM showing an example of application of the same example.
, Figure 9. 4.5...high ``y'' toro-do system unit, 8゜;] ......"ra-i c: + -
Do.

Claims (1)

[Claims] 1 In the X-ray device IL'-rl, there is an X-ray fluorescence multiplier tube that converts the transmitted XAF image of the subject into a visible light image, and a luminance detector that detects the output brightness of this X-ray fluorescence multiplier tube. The 1f detector is connected in series between the output end of the generator and the X-ray tube, which generates the high voltage to be applied to the X-ray tube, 1-1-. 7. τ
a tetrode vacuum tube, to which an X-ray exposure signal is applied; 2-a first grid bus circuit for controlling the bias voltage of its first grid to render the tetrode vacuum tube conductive; and an appropriate voltage for the X-ray fluorescence multiplier tube; Compatible with the brightness 1 position ((1-7) Compare the two reference voltages and the detection signal from the brightness detection B, and the difference between them will be reduced.
and a second grid bias circuit for controlling the bias voltage of the second grid in order to control the internal voltage drop F of the quadrupole cell and the air tank in the direction.
line equipment.