X-ray detector monitoring device

Abstract

An X-ray detector monitoring device capable of detecting a time when an X-ray detector is disabled due to a slow leak is provided. The X-ray detector monitoring device is provided with an X-ray detection element 32 for detecting X-ray intensity, an X-ray detector 30 having a vacuum insulation container 33 in which an X-ray introduction window 31 is formed, a cooling means 60 for cooling the X-ray detection element 32, a detection element temperature sensor 81 mounted on the X-ray detection element 32 to output detection element temperature information T.sub.t by detecting a temperature of an X-ray detection element 32, and a control unit 40 and 70 configured to calculate an output value for controlling the cooling means 60 to output the output value to the cooling means 60 so that the detection element temperature information T.sub.t becomes a preset temperature T.sub.S. The control unit 40 and 70 is configured to detect a vacuum state of the vacuum insulation container 33 based on the output value.

Claims

1. An X-ray detector monitoring device comprising: an X-ray detector provided with an X-ray detection element for detecting X-ray intensity and a vacuum insulation container in which an X-ray introduction window is formed; a cooling means configured to cool the X-ray detection element; a detection element temperature sensor attached to the X-ray detection element to output detection element temperature information by detecting a temperature of the X-ray detection element; and a control unit configured to calculate an output value for controlling the cooling means to output the output value to the cooling means so that the detection element temperature information becomes a preset temperature, wherein the control unit detects a vacuum state of the vacuum insulation container based on the output value.

2. The X-ray detector monitoring device as recited in claim 1, further comprising: a storage unit configured to store an output value threshold value for determining that a vacuum state is abnormal and store the output value output to the cooling means, wherein the control unit includes a replacement time prediction means for notifying a replacement time of the X-ray detector based on a temporal change of the output value and the output value threshold value.

3. The X-ray detector monitoring device as recited in claim 1, further comprising: a detector ambient temperature sensor arranged outside the X-ray detector to detect an ambient temperature of the X-ray detector to output detection unit ambient temperature information, wherein the control unit detects the vacuum state of the vacuum insulation container based on the output value and the detector ambient temperature information.

4. The X-ray detector monitoring device as recited in claim 1, wherein the cooling means is a Peltier element or a combination of liquid nitrogen and a heater.

5. The X-ray detector monitoring device as recited in claim 4, wherein the output value is a voltage value and/or a current value output to the Peltier element or the heater.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic configuration diagram showing an example of an energy dispersion type X-ray fluorescence analyzer according to the present invention.

(2) FIG. 2 is a schematic configuration diagram showing another example of an energy dispersion type X-ray fluorescence analyzer according to the present invention.

(3) FIG. 3 is a schematic configuration diagram showing a conventional energy dispersion type X-ray fluorescence analyzer.

(4) FIG. 4 is a graph showing an example of a temporal change of a current value.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

(5) Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. It should be noted that the present invention is not limited to the embodiments described below, and various embodiments are included within a range not departing from the spirit of the present invention.

First Embodiment

(6) FIG. 1 is a schematic configuration diagram showing an example of an energy dispersion type X-ray fluorescence analyzer according to an embodiment of the present invention. The same configuration as that of the energy dispersion type X-ray fluorescence analyzer 201 described above will be allotted by the same reference symbol.

(7) The energy dispersion type X-ray fluorescence analyzer 1 is provided with an analysis chamber 20 in which a sample S is arranged, a device housing 50 in which an X-ray tube 10 and an X-ray detector unit 30 are arranged, a resistance thermometer (detector ambient temperature sensor) 82, and a control board (control unit) 40 and a computer (control unit) 70 for controlling the X-ray detector unit 30 and the Peltier element 60.

(8) The resistance thermometer 82 is attached to, for example, the outer surface of the device housing 50, and detects the ambient temperature of the X-ray detector unit 30 and outputs the detector ambient temperature information T.sub.n to a temperature control output monitoring means 71b of the computer 70, which will be described later.

(9) The control board 40 has a temperature control means 40a and an integrator 40b. When the measurement is started, the temperature control means 40a performs control to receive the detection element temperature information T.sub.t from the resistance thermometer 81 in the X-ray detector unit 30 at a predetermined time interval t, calculate a current value I.sub.t so that the temperature of the X-ray detection element 32 becomes the preset temperature T.sub.S, and output the current value I.sub.t to the Peltier element 60 and the temperature control output monitoring means 71b of the computer 70.

(10) The computer 70 is provided with a CPU 71, a memory 72, and a display device 73. The functions processed by the computer 70 will be described in blocks. The computer 70 includes a measuring means 71a for acquiring the fluorescent X-ray intensity X.sub.n from the X-ray detection element 32, a temperature control output monitoring means 71b for storing the detector ambient temperature information T.sub.n and the current value I.sub.n acquired from the resistance thermometer 82 and the temperature control means 40a in an output value storage area 72b of the memory 72, and a replacement time prediction means 71c for notifying the replacement time of the X-ray detector unit 30 based on the current value I.sub.n, an output value threshold value I.sub.th, and the detector ambient temperature information T.sub.n acquired from the memory 72.

(11) The memory 72 has an output value threshold value storage area 72a for storing an output value threshold value I.sub.th for predictively determining that the vacuum state is abnormal beforehand and an output value storage area 72b for storing the current value I.sub.n output to the Peltier element 60.

(12) The temperature control output monitoring means 71b performs control to receive the detector ambient temperature information T.sub.n and the current value I.sub.n and store them in the output value storage area 72b. For example, at the time of measuring the n.sup.th sample S.sub.n, the temperature control output monitoring means 71b receives the current value I.sub.t output so that the temperature of the X-ray detection element 32 becomes the preset temperature T.sub.S and stores the average value of the current value I.sub.t in the output value storage area 72b together with the detector ambient temperature information T.sub.n at the time of measuring the n.sup.th sample S.sub.n as the current value I.sub.n at the time of measuring the n.sup.th sample S.sub.n.

(13) The replacement time prediction means 71c performs control to notify the replacement time of the X-ray detector unit 30 based on the current value I.sub.n, the output value threshold value I.sub.th, and the detector ambient temperature information T.sub.n. For example, the current value I.sub.n output at the time of the detector ambient temperature information T.sub.n at the time of measuring the n.sup.th sample S.sub.n is corrected to the current value I.sub.n which would have been output when the detector ambient temperature information Tn was the predetermined temperature T. Then, the temporal change I(n) of the current value as shown in FIG. 4 is created. With this, the time (n+) when the current value I.sub.n exceeds the output value threshold value I.sub.th is predicted. As a result, a warning message Cooling capacity exceeds the upper limit by measuring samples by a more times is displayed on the display device 73.

(14) As described above, according to the first embodiment of the present invention, the user of the device can recognize the replacement time of the X-ray detector unit 30 due to the slow leak which could not have been dealt with the notification of the exchange timing by the mere conventional integration of the operating time.

Second Embodiment

(15) FIG. 2 is a schematic configuration diagram showing another example of an energy dispersion type X-ray fluorescence analyzer according to an embodiment of the present invention. Note that the same configuration as that of the energy dispersion type X-ray fluorescence analyzer 1 and 201 described above will be allotted by the same reference symbol.

(16) The energy dispersion type X-ray fluorescence analyzer 101 is provided with an analysis chamber 20 in which a sample S is arranged, a device housing 150 in which the X-ray tube 10 and the X-ray detector unit 130 are arranged, a cooling means 160, a resistance thermometer (detector ambient temperature sensor) 82, a control board (control unit) 40 for controlling the X-ray detector unit 130 and the cooling means 160, and a computer (control unit) 170.

(17) The cooling means 160 is provided with a refrigerant container 162 accommodating a refrigerant (e.g., liquid nitrogen), a heater 161, and a copper-made heat transfer member 163.

(18) One end of the heat transfer member 163 is connected to the X-ray detection element 32 of the X-ray detector unit 130, and the other end thereof is connected to the refrigerant container 162. As a result, the other end portion of the heat transfer member 163 is cooled to a very low temperature by the refrigerant in the refrigerant container 162, and this cold heat is transmitted to the X-ray detection element 32 through the heat transfer member 163, whereby the X-ray detection element 32 is cooled to a very low temperature.

(19) The heater 161 is heated by passing a heater current of an arbitrary current value (output value) I.sub.t from the temperature control means 40a of the control board 40. As a result, the temperature of the FET (an amplifier circuit for amplifying an electric signal corresponding to the energies of the fluorescent X-rays from the X-ray detection element 32) 34 excessively cooled by the refrigerant is adjusted to the preset temperature T.sub.S.

(20) The control board 40 has a temperature control means 40a and an integrator 40b. When the measurement is started, the temperature control means 40a performs control to receive detection element temperature information T.sub.t from the resistance thermometer 81 at a predetermined time interval t, calculate the current value I.sub.t so that the temperature of the FET 34 becomes the preset temperature T.sub.S, and output the calculated current value I.sub.t to the heater 161 and the temperature control output monitoring means 71b of the computer 170.

(21) The computer 170 is provided with a CPU 171, a memory 172, and a display device 73. The function processed by the computer 170 is explained in blocks. The computer includes a measuring means 71a for acquiring the fluorescent X-ray intensity X.sub.n from the X-ray detection element 32 through the FET 34, a temperature control output monitoring means 71b for acquiring the detector ambient temperature information T.sub.n from the resistance thermometer 82 and storing the detector ambient temperature information T.sub.n and the current value I.sub.n in the output value storage area 72b, and a replacement time reporting means 171c for notifying the replacement time of the mounting portion 150a to which the X-ray detector unit 130 and the control board 40 are attached based on the current value I.sub.n, the output value threshold value I.sub.th, and the detector ambient temperature information T.sub.n acquired from the memory 172.

(22) The memory 172 has an output value threshold value storage area 172a for storing an output value threshold value I.sub.th for reporting that the vacuum state is abnormal and an output value storage area 72b for storing the current value I.sub.n output to the heater 161 of the cooling means 160.

(23) The replacement time reporting means 171c controls to notify the replacement time of the mounting portion 150a to which the X-ray detector unit 130 and the control board 40 are attached based on the current value I.sub.n, the output value threshold value I.sub.th, and the detector ambient temperature information T.sub.n. For example, the current value I.sub.n output at the time of the detector ambient temperature information T.sub.n at the time of measuring the n.sup.th sample S.sub.n is corrected to the current value I.sub.n which would have been output when the detector ambient temperature information T.sub.n was the predetermined temperature T. With this, when the current value I.sub.n exceeds the output value threshold value I.sub.th, a warning message Cooling capacity exceeds the upper limit value is displayed on the display device 73.

(24) As described above, according to the second embodiment of the present invention, the user of the device can recognize the replacement time of the mounting portion 150a to which the X-ray detector unit 130 and the control board 40 are attached due to the slow leak, which could not be dealt with by the notification of the replacement time by the mere conventional integration of the operating time.

INDUSTRIAL APPLICABILITY

(25) The present invention can be used for an X-ray fluorescence analyzer, etc., for calculating concentrations of elements contained in a sample.

DESCRIPTION OF SYMBOLS

(26) 1: X-ray fluorescence analyzer 10: X-ray tube 20: analysis chamber 30: X-ray detector unit (X-ray detector) 31: X-ray introduction window 32: X-ray detection element 33: vacuum insulation container 40: control board (control unit) 60; Peltier element (cooling means) 70; computer (control unit) 81: resistance thermometer (detection element temperature sensor)