JP6131835B2 - X-ray equipment - Google Patents

Description

  The present invention provides an X-ray apparatus that performs various measurements using X-rays from an X-ray generator using an X-ray tube, such as a fluorescent X-ray analyzer, an X-ray fluoroscopic examination apparatus, an X-ray CT apparatus, and the like. About.

  In an apparatus that performs analysis or measurement using X-rays, such as a fluorescent X-ray analyzer or an X-ray fluoroscopic examination apparatus, an X-ray tube is usually used as the radiation source. The X-ray tube has a filament (cathode) and a target (anode), and generates X-rays by causing thermal electrons emitted by applying a high voltage to the filament to collide with the target.

  In such an X-ray tube, for example, when it is used after a long period of non-use, it is not necessary to immediately apply a high voltage to the filament, but to perform a process called aging. This is preferable in that the life of the sphere is not shortened. In the aging process, normally, the voltage (tube voltage) applied to the X-ray tube is gradually increased to gradually reduce the non-uniformity of the pressure distribution in the tube due to local gas release from the target or the like. This is a relaxation process and requires a certain amount of time. Therefore, it is important to execute this aging process at an optimal timing in order to extend the life of the X-ray tube and not to waste time.

  Regarding aging of the X-ray tube, the time when the power of the X-ray tube is turned off is stored in the past, and the non-use time is calculated from the difference between the stored time and the time when the power is turned on next time. And when the non-use time has reached the preset time, the technique which prompts an operator's judgment by displaying whether to perform aging is proposed (for example, refer to patent documents 1).

  Further, in the cited document 1, when discharge generated in the driving state of the X-ray tube is detected and the discharge is performed once at the end of driving, whether or not aging is performed in the same manner as described above. It is also disclosed to prompt the operator to make a judgment. In the cited document 1, when the operator determines that aging is to be performed and inputs that effect, the tube voltage for the X-ray tube is automatically changed based on the pre-stored aging conditions to perform aging. Run.

  Conventionally, similarly to the above, the non-use time is calculated from the power-on time and the previous power-off time, and if the non-use time has reached the specified time, a plurality of preset aging is performed. A technique has been proposed in which an optimum one is selected from the conditions and aging is automatically performed (see Patent Document 2).

JP 2007-082650 A JP 2009-266688 A

  By the way, the purpose of aging is to gradually alleviate the non-uniformity of the pressure distribution in the tube due to local gas release, and the probability of such an increase in the amount of gas emission increases as the non-use time increases. However, this is not always the case. Moreover, even if the non-use time is short, the gas emission may increase. Therefore, the method of performing aging when the non-use time reaches the set time cannot be said to be able to perform aging at an optimal timing.

  On the other hand, it can be said that the technique of detecting the discharge in the X-ray tube and using it as a guideline that aging is necessary is superior in that it can sense the necessity of aging more directly.

  However, in the technique disclosed in the cited document 1, after discharge is detected in the driving state of the X-ray tube, when the driving is stopped, is the aging performed to the operator even if there is even one discharge? Since the display is performed to determine whether or not, there are the following disadvantages. First, even if a large number of discharges occur during driving of the X-ray tube, the driving continues until the operator stops driving the X-ray tube. Second, even if there is only one small discharge during driving of the X-ray tube, it is determined whether or not aging is performed to the operator when driving of the X-ray tube is stopped. This may cause unnecessary aging.

  The present invention has been made in view of such a situation, and an object thereof is to provide an X-ray apparatus capable of aging an X-ray tube at an optimal timing.

In order to solve the above problems, an X-ray apparatus according to the present invention includes an X-ray tube, a high-voltage power source that generates a high voltage to be applied to the X-ray tube, and a high-voltage power supply control circuit that controls the high-voltage power source. in X-ray apparatus provided with a discharge detecting means for detecting that discharge to the X-ray tube is generated, among the detected discharged by the discharge detection means, the discharge times exceeding the preset size Counting means for counting the number, aging condition storage means for storing the aging conditions, and when the counting result of the number of discharges n after the activation of the X-ray tube reaches a prescribed number N , the high voltage power supply control circuit On the other hand, it has drive control means for forcibly stopping the application of a high voltage to the X-ray tube, and forced stop storage means for storing the forced stop, and the drive control means stop storage means the X-ray tube When the stores that there has been forcibly stopped during startup, an instruction to perform automatic aging I follow the contents of the aging condition storage means characterized by providing the above high-voltage power supply control circuit (according Item 1).

In the present invention, a time measuring means for measuring the elapsed time t from the start point of the X-ray tube, when the discharge frequency n which is counted Ri by the said counting means has reached the predetermined number of times N And determining means for determining whether or not the elapsed time t by the time measuring means has reached a preset time threshold value T, and the aging condition storage means stores a plurality of aging conditions, The forced stop storage means stores the determination result by the determination means together with the forced stop, and the drive control means executes the aging of the X-ray tube when starting the X-ray tube. Preferably, a configuration (Claim 2) that automatically selects an aging condition according to a determination result by the determination means and gives an instruction to execute the aging to the high-voltage power supply control circuit is adopted. Can.

  The present invention detects the discharge of the X-ray tube and uses it as a measure of aging. However, a threshold value is provided for both the magnitude and the number of discharges, and discharge exceeding a preset magnitude occurs. When it reaches the specified number of times, it is determined that aging is necessary. When the determination is made, the operation of the X-ray tube is forcibly stopped. Then, when the X-ray tube is activated next time, aging is automatically executed. Therefore, according to the present invention, it is possible to eliminate the waste of performing unnecessary aging without losing the aging timing.

  The invention according to claim 2 stores a plurality of aging conditions and attempts to perform appropriate aging according to the degree of discharge. That is, when a discharge exceeding a preset size has occurred a specified number of times, information on the degree of discharge is obtained depending on whether the time to reach it is long or not, and a plurality of pre-stored information are stored for aging. Aging is executed by automatically selecting an optimum condition according to the aging condition. As a result, aging is executed at an optimal timing and under an optimal condition.

  According to the present invention, the application of high voltage to the X-ray tube is forcibly stopped when the number of occurrences of discharge of the X-ray tube exceeding a preset size reaches a specified number. Since the aging is automatically executed at the next start-up, the aging can be executed at an optimal timing without depending on the judgment of the operator.

The block diagram which shows the structure of embodiment of this invention. The graph which shows the example of the voltage (current) application pattern of the several aging conditions memorize | stored in the aging condition memory | storage part in embodiment of this invention. The flowchart which shows operation | movement of embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention. For example, it shows a portion related to X-ray generation of a fluorescent X-ray analyzer, and is configured by an X-ray generator 1 and a controller 2. Yes.

  The X-ray generator 1 includes an X-ray tube 11 that generates X-rays by applying a high voltage, a high-voltage power source 12 that generates a high voltage to be applied to the X-ray tube 11, and the high-voltage power source 12. Is provided with a high voltage power supply control circuit 13 for controlling. Further, the X-ray generator 1 is provided with a discharge detection circuit 14, a discharge current threshold storage unit 15, and a discharge number counting circuit 16. The discharge detection circuit 14 is a circuit that detects that there has been a discharge of a magnitude greater than a preset value during driving of the X-ray tube 11, and is realized by monitoring the current flowing through the X-ray tube 11, for example. When a discharge exceeding the magnitude stored in the discharge current threshold storage unit 15 occurs, a discharge detection signal is output. The counting circuit 16 counts the detection signal from the discharge detection circuit 14, and the constant value is taken into the controller 2.

  The controller 2 takes in the count value obtained by the main control unit 21 under the control of the high-voltage power supply control circuit 13 of the X-ray generator 1 and the discharge count circuit 16 of the X-ray generator 1 and performs the determination described later. A determination unit 22 to perform, a discharge number threshold storage unit 23 and a time threshold storage unit 24 for storing a discharge number threshold N and a time threshold T used for determination by the determination unit 22, and an X-ray Timing unit 25 for measuring time from the start of application of high voltage to tube 11, aging condition storage unit 26 for storing a plurality of aging conditions, and forcible stop of X-ray tube 11 described later and determination A forced stop / state storage unit 27 that stores information related to the degree of discharge by the unit 22 is provided.

  The determination unit 22 takes in the count value n by the discharge number counting circuit 16 of the X-ray generator 1, and the value n reaches the discharge number threshold value N set in the discharge number threshold storage unit 23. In the case where N is reached, the time measurement at that time by the time measuring unit 25 that measures the time from the time when the high voltage is applied to the X-ray tube 11 is measured. The result t is compared with the time threshold value T, and the magnitude relation is determined. That is, after the activation of the X-ray tube 11, it is determined whether the number of discharges has reached N times in a long time or N times in a short time. The determination result of the length of time is used as information indicating the degree of discharge. That is, the degree of discharge is greater when the number of discharges reaches N times in a short time than when the number of discharges reaches N times in a long time after activation of the X-ray tube 11, in other words, It can be estimated that the local gas release amount of the X-ray tube 11 is large.

  The determination result by the determination unit 22 is sent to the main control unit 21. Based on the determination result, the main control unit 21 is configured to forcibly stop the application of a high voltage to the X-ray tube 11 when the discharge number n reaches the discharge number threshold value N. Command. At the same time, the forced stop and the determination result regarding the length of time by the determination unit 22 are stored in the forced stop / state storage unit 27.

  When the high-voltage power supply 12 is started to generate X-rays, the main control unit 21 reads the contents of the forced stop / state storage unit 27, and when the previous stop is a forced stop, the discharge is performed N times. An aging condition corresponding to the length of time until it reaches is selectively read from the aging condition storage unit 26, and a command is issued to the high-voltage power supply control circuit 13 to execute aging under the condition.

  A plurality of aging conditions stored in the aging condition storage unit 26 will be described with reference to FIG. FIG. 2 is a graph showing an example of a pattern of voltage (or current) applied to the X-ray tube 11 during aging. The horizontal axis is time, and the horizontal axis is voltage (or current). In this example, there are two types of aging conditions, Condition 1 and Condition 2.

  Condition 1 is selected when the time from when the high voltage is applied to the X-ray tube 11 to start the generation of X-rays until the number of discharges n reaches N is longer than the time threshold value T. This is an aging condition, and is generated locally in the X-ray tube 11 by gradually increasing the voltage (current) applied to the X-ray tube 11 by a constant voltage (current) every predetermined time. It is possible to gradually alleviate the non-uniformity of the pressure distribution due to the released gas.

  On the other hand, the condition 2 is when the time from when the high voltage is applied to the X-ray tube 11 to start the generation of X-rays until the number of discharges n reaches N is shorter than the time threshold T. The selected aging condition is such that the voltage (current) applied to the X-ray tube 11 is gradually increased by a larger voltage (current) every time longer than the condition 1. According to the aging based on the condition 2, even if the local gas emission in the X-ray tube 11 is temporarily large, the process proceeds to the next stage after waiting for the relaxation, and further discharge occurs during the aging. Can reduce the risk.

  Here, the controller 2 is actually composed mainly of a CPU and its peripheral devices and operates according to the installed program. In FIG. 1, for convenience of explanation, each function realized by executing the program is a function. Shown for each block.

Now, the operation of the embodiment of the present invention having the above-described configuration will be described step by step with reference to the flowchart shown in FIG.
When a start command is given to the high-voltage power supply 12 by operating an operation unit (not shown), it is first determined from the content of the forced stop / state storage unit 27 whether the previous stop was a forced stop (ST1). If it is not stopped, the contents of the counter 16 that counts the number of discharges n are reset and time counting is started (ST2), the high-voltage power supply 12 is normally started, and a high voltage is applied to the X-ray tube 11. X-rays are generated (ST3).

  During this normal operation, the discharge detection circuit 14 and the discharge frequency counting circuit 16 count discharges exceeding a preset magnitude (ST4, ST5). When the count value n reaches the number-of-thresholds N stored in the discharge number-threshold threshold storage unit 23, a command is issued to the high-voltage power supply control circuit 13, and the high voltage applied to the X-ray tube 11 is increased. Is stopped (ST6, ST7). At the same time, after the application of the high voltage to the X-ray tube 11 is started, the time t until the discharge number n reaches N, and the time threshold value T stored in the time threshold value storage unit 24 (ST8), the result and the forced stop are stored in the forced stop / state storage unit 27, and the operation is terminated (ST9, ST10).

  On the other hand, when a start command is given to the high-voltage power supply 12, if it is recognized in ST1 that the previous stop was a forced stop from the stored contents of the forced stop / state storage unit 27, the forced stop / state storage unit 27 is also informed. Depending on the information about the length of time written, the corresponding one of a plurality of aging conditions stored in the aging condition storage unit 26, that is, the condition 1 when t is longer than T, the discharge when it is shorter The condition 2 is selectively read, and a command is issued to the high-voltage power supply control circuit 13 to execute aging under the condition (ST21, ST22, ST23). At the same time, the stored contents of the forced stop / state storage unit 27 are deleted (ST24). When the above aging is completed, the process returns to ST2 and below, and the X-ray tube 11 is normally driven.

  According to the above embodiment of the present invention, the driving of the X-ray tube 11 is forcibly stopped when aging is necessary, and the aging is automatically performed under the optimal aging condition at the time of restart. As a result, the operator does not have to make any judgments or considerations regarding aging.

  In the present invention, the technique described in Patent Document 2 described above, that is, when the non-use time of the X-ray tube is measured and it is determined that the non-use state continues for a predetermined time, is automatically It is not disturbed to use together with the technology that performs aging. However, when the present invention and the technique of the cited document 2 are used together, the threshold value of the non-use time in the cited document 2 can be determined by the present invention because the case where aging is necessary can be reliably grasped. It is preferable to set the length longer than in the case of using.

DESCRIPTION OF SYMBOLS 1 X-ray generator 2 Controller 11 X-ray tube 12 High voltage power supply 13 High voltage power supply control circuit 14 Discharge detection circuit 15 Discharge current threshold value memory | storage part 16 Discharge count circuit 21 Main control part 22 Discriminating part 23 Discharge frequency threshold value Storage unit 24 hour threshold storage unit 25 Timing unit 26 Aging condition storage unit 27 Forced stop / state storage unit

Claims (2)

And X-ray tube, a high voltage power supply for generating a high voltage to be applied to the X-ray tube, the X-ray apparatus having a high-voltage power supply control circuit for controlling the high voltage power supply,
A discharge detecting means for detecting that a discharge has occurred in the X-ray tube; a counting means for counting the number of discharges exceeding a preset magnitude among the discharges detected by the discharge detecting means;
Aging condition storage means for storing aging conditions;
When the counting result of the number of discharge times n after activation of the X-ray tube has reached a prescribed number N, forcibly stops the application of a high voltage to the X-ray tube with respect to the high-voltage power supply control circuit Drive control means, and forced stop storage means for storing that the forced stop has occurred,
Said drive control means, when the forced stop storing means stores that there has been suspended at the start of the X-ray tube, a command for executing the automatic aging according to the contents of the aging condition storage unit To the high-voltage power supply control circuit. Timing means for measuring the elapsed time t from the start point of the X-ray tube, the elapsed time by the time counting means at the time of discharge number n of times counted Ri by the said counting means has reached the predetermined number of times N t Includes a determination means for determining whether or not a preset time threshold value T has been reached, the aging condition storage means stores a plurality of aging conditions, and the forced stop storage means The determination result by the determination means is stored together with the stop, and the drive control means determines the determination result by the determination means when executing the aging of the X-ray tube when starting the X-ray tube. 2. The X-ray apparatus according to claim 1, wherein a command for executing aging by automatically selecting a corresponding aging condition is given to the high-voltage power supply control circuit.

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