JPH025398A - Power unit for x-ray tube - Google Patents

Abstract

PURPOSE:To continuously and automatically implement the setting operation by providing a tube voltage/tube current detecting means and generating a schedule increasing or decreasing the power based on the detected value. CONSTITUTION:The tube voltage and the tube current applied to an X-ray tubular bulb 2 are detected by a tube voltage/tube current detecting means 8, an on/off directing means 10 directs the power to be applied to the tubular bulb 2 based on the detected value. When on or off is directed by the directing means 10, power-up or down schedule calculating means 14 and 12 generate a schedule increasing or decreasing the power based on the detected value of the means 8. The above schedule is timewise linearly implemented. A schedule implementing means 16 outputs the signal controlling the tube voltage or the tube current to an X-ray tube voltage adjusting means 4 or a current adjusting means 6 based on the calculation results of the circuits 12 and 14. The setting operation can be automatically and continuously implemented.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial field of application The present invention is applicable to various devices equipped with an X-ray tube, such as an X-ray fluorescence analyzer or an X-ray diffraction device. The present invention relates to an X-ray tube power supply device for supplying voltage and tube current.

(b) Conventional technology In fluorescent X-ray analyzers, X-ray tube diffractometers, etc.,
A power supply device is provided for applying a tube voltage and a tube current to the wire tube. When the apparatus is in use, a high tube voltage of several tens of kilovolts is applied to the X-ray tube by this power supply to generate X-rays.

By the way, when starting the equipment, the tube voltage and tube current applied to the X-ray tube are gradually increased until the desired operating state for generating X-rays is reached, and when the equipment is stopped, the tube voltage and current applied at the moment are increased. It is necessary to gradually reduce the voltage and tube current. In other words, if a high tube voltage is instantaneously applied to the X-ray tube, or if a large current flows while the tube voltage is low, the filament may be damaged by discharge and the life of the XI tube may be shortened. bring about a decline. For this reason, in the past, the tube voltage and tube voltage setting dials were manually switched step by step without checking the meter's deflection.

(c) Problems to be Solved by the Invention However, it is not preferable to manually switch the tube voltage and tube current because the operation is complicated and there is a risk of operational errors.

The present invention has been made in view of the above circumstances, and it automates the setting operations of the tube voltage and tube current supplied to the X-ray tube to eliminate the cumbersome setting operations, and also eliminates the cumbersome setting operations. , the tube current can be switched continuously, reducing the impact of the discharge on the filament, etc., and reducing the
The purpose is to improve the lifespan of wire tubes.

(d) Means for Solving the Problems In order to achieve the above object, the present invention provides an X-ray tube voltage adjusting means for increasing or decreasing the tube voltage applied to the X-ray tube, and a means for adjusting the tube voltage applied to the X-ray tube. An X-ray tube power supply device equipped with an X-ray tube current adjustment means for increasing or decreasing tube current has the following configuration.

That is, the X-ray tube power supply device of the present invention includes a tube voltage/tube current detection means for detecting the tube voltage and tube current applied to the X-ray tube, and a tube voltage/tube current detection means for detecting the tube voltage and tube current applied to the X-ray tube, and a an on/off instruction means for instructing on/off of the voltage x tube voltage); and a tube voltage detected by the tube voltage/tube current detection means in response to a power-off instruction from the on/off instruction means. , a power-down schedule calculation means for creating a power-down schedule for linearly decreasing the power over time based on the value of the tube current; power-up schedule calculation means for creating a power-up schedule for linearly increasing power over time based on values of tube voltage and tube current detected by the voltage and tube current detection means; and calculation results of both said calculation means. Based on this, a control signal for increasing or decreasing the tube voltage is sent to the X-ray tube voltage adjusting means, and a control signal for increasing or decreasing the tube current is sent to the X-ray tube current adjusting means.
The present invention is characterized by comprising a time schedule and execution means for outputting the respective time schedules.

(Po) Effect In the above configuration, when a power-off instruction signal is output from the on/off instruction means, the power-down schedule calculation means responds to the current tube voltage detected by the tube voltage/tube current detection means. Create a power down schedule that linearly reduces power over time based on voltage and tube current values.

The time schedule execution means outputs a control signal for reducing the tube voltage to the X-ray tube voltage adjustment means and a control signal for reducing the tube current to the X-ray tube current adjustment means based on the data of the power down schedule. do. As a result, the power applied to the X-ray tube is linearly reduced over time.

On the other hand, when a power-on instruction signal is output from the on/off instruction means, in response, the power-up schedule calculation means outputs the current tube voltage and tube current values detected by the tube voltage and tube current detection means. Create a power-up schedule that linearly increases power over time based on . The time schedule execution means sends a control signal for increasing the tube voltage to the X-ray tube voltage adjustment means and a control signal for increasing the tube current to the X-ray tube current adjustment means based on the data of the power-up schedule. Output each. As a result, the power applied to the X-ray tube increases linearly over time.

(f) Example FIG. 1 is a block diagram of the X-ray tube power supply device.

In the figure, 1 is an X-ray tube power supply device, 2 is an X-ray tube, and 4
Reference numeral 6 indicates an X-ray tube voltage adjusting means for increasing or decreasing the tube voltage applied to the X-ray tube 2, and 6 indicates an X-ray tube current adjusting means for increasing or decreasing the tube current applied to the X-ray tube 2.

Reference numeral 8 denotes tube voltage/tube current detection means for detecting the tube voltage and tube current applied to the X-ray tube 2, and is composed of, for example, a voltmeter and an ammeter. Reference numeral 10 denotes on/off instruction means for instructing on/off of the power (-tube voltage x tube voltage) applied to the X-ray tube 2, and is comprised of, for example, a keyboard.

12, in response to a power-off instruction from the on/off instruction means 10, the power is linearly reduced over time based on the tube voltage and tube current detected by the tube voltage/tube current detection means 8; A power-down schedule calculation means 14 for creating a power-down schedule for adjusting the tube voltage and
This is a power-up schedule calculation means that creates a power-up schedule for linearly increasing the power over time based on the values of the tube voltage and tube current detected by the tube current detection means 8. Further, 16 sends a control signal to increase or decrease the tube voltage to the X-ray tube voltage adjustment means 4, and a control signal to increase or decrease the tube current to the
It is a time schedule execution means that outputs to the tube current adjustment means 6 respectively. Both calculation means 12, 14 and time schedule execution means 16 are composed of, for example, a microcomputer.

Next, the power-down and power-up control operations of the X-ray tube 2 of the X-ray tube power supply device uI having the configuration described in "2" will be explained along the flowcharts of FIGS. 2 and 3.

(1) A power-down instruction signal (
For example, when a low level signal) is output, the power down schedule calculation means 12 confirms this power down instruction (step ■) and then calculates the current tube voltage V detected by the tube voltage/tube current detection means 8. . , tube current I. Create a power down schedule that linearly reduces power based on the value of (step ■).

That is, the power down schedule calculation means I2 is
First, as shown in FIG. 3, the tube voltage/tube current detection means 8
The tube voltage V detected at The currently set power po (=voX I o) is calculated from the value of the tube current Io.

In addition, the current power is determined from both the power reduction slope k (for example, low/5ec) per unit time, which is preset so as not to cause sudden thermal changes to the X-ray tube 2, and the above power P0. Time T required for Pa to become zero
d, and each time Tj (=j ・ΔT, j=1.2, "'n
, ΔT=Td/n) and the power Pj after the lapse of time are calculated based on the following equations.

Pj=PO−k−Tj (1)T
d=P, /k (2) Subsequently, the power down schedule calculation means 12 calculates the maintenance voltage Vl, which is preset to prevent the filament of the X-ray tube 2 from being damaged by discharge, and the current tube voltage V. . From each point, the tube voltage Vj and tube current Ij after each time Tj have elapsed are calculated based on the following equations.

VJ=VQ'rJ-(vo v,)/Td
(3) Ij=Pj/Vj
(4) In this way, when the values of tube voltage Vj and tube current ■j are calculated for each time Tj and the power down schedule is determined, the data of this power down schedule is sent to the time schedule execution means 16 of the blower. be done.

The time schedule execution means 16 determines whether or not the tube voltage Vj matches the stop voltage v1 (Step 2).
, if they do not match, then a control signal is sent to the X-ray tube voltage adjustment means 4 to reduce the tube voltage ■j every time Tj elapses, and also to adjust the tube current. A control signal for lowering 1j is outputted to the X-ray tube current adjusting means 6, respectively. As a result, the power Pj (=Vjxlj) applied to the X-ray tube 2 has a constant slope k
(step ■).

When the predetermined time Td elapses and the tube voltage V matches the maintenance voltage V1 (step ■), the tube current N becomes zero at this point, so next, the time schedule execution means I6 performs the following steps.
A control signal is output only to the XvA tube voltage adjustment capillary stage 4, and the tube voltage vj is lowered at a preset constant slope Q (for example, 5 kV/5ec) (step ■).
. When the tube voltage v5 becomes zero (step ■), the control operation is stopped (step ■).

(11) Power-up instruction signal (
For example, when a high-level signal (for example, a high level signal) is output, the power-up schedule calculation means I4 confirms this power-up instruction (step ■) and then takes steps to prevent the filament of the X-ray tube 2 from being damaged by discharge, etc. Set current increase permission voltage V.

A power-up schedule for increasing the power Pi linearly from to the target value V is created (step 0).

That is, the power-up schedule calculation means X2 is
First, as shown in FIG. 5, the target power P3 (=VIXr3) is determined from the target tube voltage V3 and tube current 13. In addition, the power increase gradient q(
For example, Low/5ec) and the above target power P
, the time 'ru required to reach the target power P3 and each time Ti (=i・ΔT, i=1,2
, ·-m, ΔT=Tu/m) and the power Pi after the elapse of time are calculated based on the following equations.

Pi=q −Ti (5) Tu
=P3/Q (6) Subsequently, the power down schedule calculation means 12 calculates the tube voltage after each time period Ti has passed from the current increase permission voltage 2 of the tube voltage, the target value V3, and the time Tu of equation (6). Vi and tube current 1i are calculated based on the following equations.

vi=v2+'ri・(V3 Vt)/Tu (7
)Ii=Pi/Vi (8) In this way, when the values of tube voltage Vi and tube current ■1 are calculated for each time Ti and the power-up schedule is determined, the data of this power-up schedule is used for the next time. It is sent to the schedule execution means I6.

The time schedule execution means 16 first calculates the tube voltage Vi.
Step 81) determines whether or not the current increase permission voltage V matches the current increase permission voltage V, and if they do not match, the tube voltage Vi is set at a preset constant slope r while keeping the tube current Ii at a constant value. (for example, 5kV/5ec) (step ■). Then, the tube voltage Vi is the current increase permission voltage V
, (step @), then it is determined whether the tube voltage Vi matches the target value V, (7 (step ■)
), if they do not match, a control signal is sent to the X-ray tube voltage adjustment means 4 to increase the tube voltage v1 every time each time Ti elapses, based on the data of the power-up schedule set previously; A control signal for increasing the tube current 1i is outputted to the X-ray tube current adjusting means 6, respectively. As a result, the power Pi applied to the X-ray tube 2 is increased with a constant gradient q (step ■). Then, after the predetermined time Tu has elapsed, when the tube voltage Vi matches the target value V3, that is, reaches the target power P3 (step ■), the control operation is stopped (step ■).

In the above embodiment, the time schedule for each time Tj1Ti is calculated in advance, but the values of the current tube voltage VjSVi and tube currents 1j and Ii from the tube voltage tube current detection means 8 are input. Then, sequentially, the tube voltage V j l
It is also possible to determine control values for q V i + and tube current I J I, Ii.

(g) Effects According to the present invention, the setting operations for the tube voltage and tube current applied to the X-ray tube are automated, so the complexity of the setting operations is eliminated. Furthermore, since the tube voltage and tube current can be switched continuously rather than stepwise, the shock of discharge applied to the filament etc. is reduced, making it possible to further extend the life of the X-ray tube than before. The effect is demonstrated.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a block diagram of the X-ray tube power supply device, FIG. 2 is a flowchart of power-down control operation, FIG. 3 is a flowchart of power-up control operation, and FIG. 4 is a flowchart of power-up control operation. 5 is an explanatory diagram of the procedure for creating a power-down schedule, and FIG. 5 is an explanatory diagram of the procedure for creating a power-up schedule. l... X-ray tube power supply device, 2... X-ray tube, 4... X-ray tube voltage adjusting means, 6- X-ray tube current adjusting means, 8... Tube voltage tube current detecting means, 10... - On/off instruction means, 12... Power down schedule calculation means, 14...
Power-up schedule calculation means, I6... Time schedule execution means.

Claims (1)

[Claims] (1) An X-ray tube power supply device equipped with an X-ray tube voltage adjustment means for increasing or decreasing the tube voltage applied to the X-ray tube, and an X-ray tube current adjustment means for increasing or decreasing the tube current applied to the X-ray tube. , a tube voltage/tube current detection means for detecting the tube voltage and tube current applied to the X-ray tube; and a tube voltage/tube current detection means for detecting the tube voltage and tube current applied to the X-ray tube; In response to the power-off instruction from the on/off instruction means, the power is controlled based on the values of the tube voltage and tube current detected by the tube voltage and tube current detection means. a power down schedule calculation means for creating a power down schedule for decreasing the power linearly over time; and a power down schedule calculation means for generating a power down schedule that is detected by the tube voltage/tube current detection means in response to a power on instruction from the on/off designation means. power-up schedule calculation means for creating a power-up schedule for linearly increasing power over time based on the values of tube voltage and tube current; and control for increasing and decreasing the tube voltage based on the calculation results of both said calculation means. An X-ray tube power supply device comprising: time schedule execution means for outputting a signal to the X-ray tube voltage adjustment means and a control signal for increasing or decreasing the tube current to the X-ray tube current adjustment means. .