X-ray fluorescence analyzer and power supply device

Abstract

The invention provides a fluorescent X-ray analyzer and a power supply device. In a fluorescent X-ray analysis device, a power supply for applying a tube voltage to a target includes: at least one transformer; a switching circuit connected to a primary side of the at least one transformer; and a substrate connected to the switching circuit and the at least one transformer, the substrate having a first layer and a second layer. The at least one transformer includes a first primary winding and a second primary winding on a primary side. A first wiring pattern connecting the first primary winding and the switching circuit is formed in the first layer. A second wiring pattern connecting the second primary winding and the switching circuit is formed in the second layer. The first layer and the second layer are disposed such that at least a portion of the first wiring pattern overlaps the second wiring pattern in a plan view of the substrate from the lamination direction.

Description

Technical Field

[0001] The present disclosure relates to a fluorescent X-ray analysis device and a power supply device. Background Art

[0002] Conventionally, in a method of irradiating a specimen with X-rays to analyze the specimen, an X-ray generating device has been used. In the X-ray generating device, X-rays are generated by applying a high voltage called tube voltage between a cathode electrode and a target electrode. In the X-ray generating device, in order to boost the voltage, a converter as described in Japanese Unexamined Patent Application Publication No. 2013-187929 (Patent Document 1) is sometimes used. For example, an X-ray generating device that uses a DC / DC converter to generate X-rays is described in Japanese Unexamined Patent Application Publication No. 2010-212072 (Patent Document 2). Summary of the Invention

[0003] When a switching element such as a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) is used in a converter, a surge voltage is sometimes generated when the switching element is controlled from an on state to an off state. If the surge voltage exceeds the rated voltage value of the switching element, the switching element may be damaged. If a switching element with a high rated voltage value is used, the occurrence of a failure caused by the surge voltage can be suppressed, but the cost increases.

[0004] The magnitude of the generated surge voltage varies according to the magnitude of the loop inductance of a loop path including the switching element. For example, in the power supply device described in Patent Document 1, if the inductance component between the switching element and the primary winding of the transformer is reduced, the generated surge voltage becomes smaller. That is, if the length of the wiring from the switching element to the primary winding is shortened, the magnitude of the generated surge voltage can be reduced.

[0005] However, both the switching element and the primary winding of the transformer are heating elements. When the physical distance between the switching element and the primary winding of the transformer becomes small, the heating elements become dense and the temperature of the power supply device rises.

[0006] The present disclosure has been made to solve the above problems, and an object thereof is to reduce the turn-off surge voltage while maintaining the distance between the switching element and the primary winding of the transformer.

[0007] A fluorescence X-ray analysis apparatus according to one aspect of the present disclosure includes: an X-ray tube including a filament and a target, for irradiating a specimen with primary X-rays; a detector for detecting secondary X-rays generated from the specimen; and a power supply for applying a tube voltage to the target. The power supply includes: at least one transformer; a switching circuit connected to the primary side of at least one transformer; and a substrate connected to the switching circuit and at least one transformer, the substrate having a first layer and a second layer, wherein at least one transformer includes a first primary winding and a second primary winding on the primary side, a first wiring pattern connecting the first primary winding to the switching circuit is formed on the first layer, a second wiring pattern connecting the second primary winding to the switching circuit is formed on the second layer, and the first layer and the second layer are configured such that at least a part of the first wiring pattern overlaps with the second wiring pattern when the substrate is viewed from above in the stacking direction.

[0008] A power supply device according to an aspect of the present disclosure is a power supply device for applying a tube voltage to a target disposed in an X-ray tube, the power supply device including: at least one transformer; a switching circuit connected to the primary side of at least one transformer; and a substrate connected to the switching circuit and at least one transformer, the substrate having a first layer and a second layer, wherein at least one transformer includes a first primary winding and a second primary winding on the primary side, a first wiring pattern connecting the first primary winding to the switching circuit is formed on the first layer, a second wiring pattern connecting the second primary winding to the switching circuit is formed on the second layer, and the first layer and the second layer are configured such that at least a part of the first wiring pattern overlaps with the second wiring pattern when the substrate is viewed from above in the stacking direction.

[0009] Based on the following detailed description of the present invention that can be understood in association with the accompanying drawings, the above objects, features, aspects, and advantages of the present invention, as well as other objects, features, aspects, and advantages, will become clear. Description of the Drawings

[0010] Figure 1 is a diagram schematically showing a power supply device and an X-ray tube included in a fluorescence X-ray analysis apparatus.

[0011] Figure 2 is a diagram for explaining the internal structure of a step-up DCDC converter disposed in a high-voltage power supply unit in Embodiment 1.

[0012] Figure 3 is a top view of a printed circuit board in Embodiment 1.

[0013] Figure 4 is a top view of layer Ly1 included in the printed circuit board in Embodiment 1.

[0014] Figure 5It is a top view of the layer Ly2 included in the printed circuit board in Embodiment 1.

[0015] Figure 6 It is a top view for explaining the path in Comparative Example 1.

[0016] Figure 7 It is a top view for explaining the path in Comparative Example 2.

[0017] Figure 8 It is a top view of the layer Ly1 included in the printed circuit board in Embodiment 2.

[0018] Figure 9 It is a top view of the layer Ly2 included in the printed circuit board in Embodiment 2. Detailed Embodiment

[0019] [Embodiment 1]

[0020] While referring to the attached Figure 1 drawings, this embodiment will be described in detail. In addition, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated in principle.

[0021] <Structure of Power Supply Device and X-ray Tube>

[0022] Figure 1 It is a diagram schematically showing a power supply device 100 and an X-ray tube 200 included in the fluorescent X-ray analysis device 1000. The fluorescent X-ray analysis device 1000 is, for example, an energy dispersive type fluorescent X-ray analysis device (EDX: Energy Dispersive X-ray Fluorescence Spectrometer). In the present embodiment, an example of applying the power supply device 100 that generates primary X-rays to the fluorescent X-ray analysis device 1000 will be described.

[0023] As Figure 1 shown, the fluorescent X-ray analysis device 1000 includes a power supply device 100, an X-ray tube 200, and a detector 300. The power supply device 100 applies a voltage to the X-ray tube 200 to generate primary X-rays 10. The primary X-rays 10 are irradiated onto the specimen S. The specimen S irradiated with the primary X-rays 10 emits fluorescent X-rays 20. The fluorescent X-rays 20 emitted from the specimen S are called "secondary X-rays" with respect to the primary X-rays. The detector 300 detects the fluorescent X-rays 20. Thus, the fluorescent X-ray analysis device 1000 can perform quantitative analysis or qualitative analysis of the specimen S.

[0024] Inside the X-ray tube 200, a target Tg1 and a filament F1 are disposed. The target Tg1 is an anode, and the filament F1 is a cathode. Inside the X-ray tube 200, the target Tg1 and the filament F1 are disposed at a distance from each other. The power supply device 100 includes a filament power supply unit 110, a high-voltage power supply unit 120, and a tube current control unit 130.

[0025] The filament power supply unit 110 heats the filament F1 by supplying current to the filament F1. Hereinafter, the current supplied from the filament power supply unit 110 to the filament F1 is referred to as "filament current".

[0026] The high-voltage power supply unit 120 applies a high voltage between the target Tg1 and the filament F1. Hereinafter, the high voltage applied by the high-voltage power supply unit 120 is referred to as "tube voltage". The high-voltage power supply unit 120 uses a rectifier, a converter, a Cockcroft-Walton circuit, etc. to boost the DC voltage converted from the commercial power supply by the switching power supply to generate a high voltage. In addition, the high-voltage power supply unit 120 can correspond to the "power supply" of the present disclosure.

[0027] As Figure 1 shown. The high-voltage power supply unit 120 is connected to the target Tg1 via the power line L3. In addition, the high-voltage power supply unit 120 is connected to the ground terminal GND via the power line L5. Inside the X-ray tube 200, the filament F1 is heated by the filament power supply unit 110, thereby generating thermoelectrons. By applying the tube voltage between the filament F1 and the target Tg1 by the high-voltage power supply unit 120, the thermoelectrons strike the target Tg1. Thereby, the primary X-ray 10 is excited.

[0028] As Figure 1 shown, the filament power supply unit 110 is connected to the filament F1 via the power line L1 and the power line L1A. The power line L1 is connected to one end of the filament F1, and the power line L1A is connected to the other end of the filament F1. The terminals T1, T1A of the filament power supply unit 110 are respectively connected to the power lines L1, L1A. The terminals T2, T2A of the power supply device 100 are connected to the filament F1.

[0029] The connection point Cp1 is the connection point between the connection point between the terminals T1 and T2 and the connection point between the terminals T1A and T2A. A resistor R322 is connected between the connection point between the terminals T1 and T2 and the connection point Cp1. A resistor R316 is connected between the connection point between the terminals T1A and T2A and the connection point Cp1.

[0030] One end of the power line L4 is connected to the connection point Cp1, and the other end of the power line L4 is connected to the ground terminal GND via a resistor. In addition, one end of the power line L4 may be connected to the connection point between the terminals T1 and T2, or the connection point between the terminals T1A and T2A, instead of being connected to the connection point Cp1.

[0031] The tube current control unit 130 performs feedback control to adjust the output of the filament power supply unit 110 based on the current value of the current flowing in the power line L4. More specifically, the tube current control unit 130 uses a resistor to convert the tube current flowing through the power line L4 into a voltage value and amplifies it through the amplifier Am1, thereby detecting the tube current value of the tube current flowing in the power line L4. The tube current control unit 130 sends the detected tube current value to the filament current control unit 111. The filament power supply unit 110 adjusts the output filament current based on the tube current value detected by the tube current control unit 130.

[0032] In the fluorescence X-ray analysis apparatus 1000 of the present embodiment, a boost DCDC converter inside the high-voltage power supply unit 120 is used to boost the voltage. Next, Figure 2 The internal structure of the boost DCDC converter 500 included in the high-voltage power supply unit 120 will be described.

[0033] Figure 2 FIG. is for explaining the internal structure of the boost DCDC converter 500 included in the high-voltage power supply unit 120 in Embodiment 1. The DCDC converter 500 in Embodiment 1 is a DCDC converter, and more specifically, a push-pull converter.

[0034] As Figure 2 shown, the DCDC converter 500 includes a transformer primary side circuit 401, a transformer secondary side circuit 402, and a transformer 30. The transformer 30 includes primary windings Tr11, Tr12 included in the transformer primary side circuit 401, and a secondary winding Tr2 included in the transformer secondary side circuit 402. In addition, the transformer 30 can correspond to the "at least one transformer" of the present disclosure. Further, the primary winding Tr11 can correspond to the "first primary winding" of the present disclosure. And, the primary winding Tr12 can correspond to the "second primary winding" of the present disclosure.

[0035] By driving the switching elements Mf1 and Mf2, the DCDC converter 500 boosts the DC voltage of 24V applied from the power supply voltage VCC. The DC voltage applied from the power supply voltage VCC is generated by rectifying a commercial power supply or the like. In addition, the DC voltage applied from the power supply voltage VCC may be a voltage other than 24V. The voltage boosted by the DCDC converter 500 is further boosted to the output voltage of the high-voltage power supply unit 120 by a Cockcroft-Walton circuit or the like. The output voltage of the high-voltage power supply unit 120 is, for example, 60 kV.

[0036] As Figure 2 shown, the primary winding Tr11 has an end H1 and an end H3. In the transformer primary side circuit 401, a path Pt3 is connected to the end H3 of the primary winding Tr11. The path Pt3 is the path between the inductor L10 and the end H3. In addition, a path Pt1 is connected to the end H1 of the primary winding Tr11. The path Pt1 is the path between the end H1 and the drain terminal of the switching element Mf1.

[0037] The primary winding Tr12 has an end H2 and an end H4. A path Pt4 is connected to the end H4 of the primary winding Tr12. The path Pt4 is the path between the inductor L10 and the end H4. In addition, a path Pt2 is connected to the end H2 of the primary winding Tr12. The path Pt2 is the path between the end H2 and the drain terminal of the switching element Mf2.

[0038] Both ends of the inductor L10 are connected to the ground terminal GND via a plurality of capacitors. Specifically, capacitors C5, C6, and C7 are connected in parallel between one end of the inductor L10 and the ground terminal GND. In addition, capacitors C8 to C12 are connected in parallel between the other end of the inductor L10 and the ground terminal GND. The capacitors C5 to C12 function as bypass capacitors for removing AC components.

[0039] The end H3 of the primary winding Tr11 is connected to the power supply voltage VCC via the path Pt3 and the inductor L10. On the other hand, the end H1 of the primary winding Tr11 is connected to the drain terminal of the switching element Mf1 via the path Pt1. In the first embodiment, the switching element Mf1 is, for example, a MOSFET, and is an element for switching the current supply to the primary winding Tr11. A buffer circuit Sn1 is connected between the drain terminal and the source terminal of the switching element Mf1. The buffer circuit Sn1 is a protection circuit for suppressing the transient high voltage generated when the switching of the switching element Mf1 is turned off.

[0040] The gate terminal of the switching element Mf1 is connected to the drive circuit 350 via the resistor R2. The drive circuit 350 performs PWM (Pulse Width Modulation) control on the switching element Mf1. A resistor R4 and a bidirectional Zener diode D1 are connected in parallel between the gate terminal and the source terminal of the switching element Mf1. The bidirectional Zener diode D1 is provided to protect the switching element Mf1 when an overvoltage occurs at the gate terminal of the switching element Mf1.

[0041] Similarly, the circuit connected to the primary winding Tr12 will also be described. The end H4 of the primary winding Tr12 is connected to the power supply voltage VCC via the path Pt4 and the inductor L10. On the other hand, the end H2 of the primary winding Tr12 is connected to the switching element Mf2 via the path Pt2. Similarly to the switching element Mf1, the switching element Mf2 is, for example, a MOSFET and is an element for switching the current supply to the primary winding Tr12.

[0042] A snubber circuit Sn2 is connected between the drain terminal and the source terminal of the switching element Mf2. The snubber circuit Sn2 is a protection circuit for suppressing the transient high voltage generated when the switching element Mf2 is switched off. In some aspects, the switching elements Mf1 and Mf2 may be IGBTs (Insulated Gate Bipolar Transistors) instead of MOSFETs. In addition, the switching element Mf1 can correspond to the "first switching element" of the present disclosure. Further, the switching element Mf2 can correspond to the "second switching element" of the present disclosure. Also, both the switching element Mf1 and the switching element Mf2 can correspond to the "switching circuit" of the present disclosure. Additionally, the snubber circuit Sn1 can correspond to the "first snubber circuit" of the present disclosure. The snubber circuit Sn2 can correspond to the "second snubber circuit" of the present disclosure.

[0043] The gate terminal of the switching element Mf2 is connected to the drive circuit 350 via the resistor R6. The drive circuit 350 performs PWM control on the switching element Mf2. A resistor R8 and a bidirectional Zener diode D2 are connected in parallel between the gate terminal and the source terminal of the switching element Mf2. The bidirectional Zener diode D2 is provided to protect the switching element Mf2 when an overvoltage occurs at the gate terminal of the switching element Mf2.

[0044] The drive circuit 350 repeatedly turns on and off the switching element Mf1 and repeatedly turns on and off the switching element Mf2 to alternately supply current to the primary winding Tr11 and the primary winding Tr12. The drive circuit 350 controls each of the switching elements Mf1 and Mf2 so that the switching elements Mf1 and Mf2 do not simultaneously become in the on state.

[0045] As Figure 2 shown, the source terminals of the switching elements Mf1 and Mf2 are respectively connected to one ends of the resistors R10 and R11. The other end of the resistor R10 is connected to the ground terminal GND. Similarly, the other end of the resistor R11 is connected to the ground terminal GND.

[0046] Thus, the high-voltage power supply unit 120 in the present embodiment has a DCDC converter 500 that repeatedly drives the switching elements Mf1 and Mf2 to boost the voltage. In the present embodiment, when the switching elements Mf1 and Mf2 are switched from the on state to the off state, a surge voltage sometimes occurs. Hereinafter, this surge voltage is referred to as the "turn-off surge voltage".

[0047] The cause of the turn-off surge voltage is that the parasitic capacitance of the switching element is overcharged due to the influence of the loop inductance of the loop path including the switching element. When the turn-off surge voltage exceeds the rated voltage value of the switching elements Mf1 and Mf2, the switching elements Mf1 and Mf2 sometimes malfunction.

[0048] If the leakage inductance between the primary windings Tr11 and Tr12 is reduced, the inductance component between the switching element Mf1 and the primary winding Tr11 becomes smaller, and the turn-off surge voltage generated in the switching element Mf1 becomes smaller. If the length of the path Pt1 is shortened, the inductance component becomes smaller. However, if the length of the path Pt1 is shortened, the physical distance between the switching element Mf1, which is a heating element, and the primary winding Tr11 becomes shorter, and the heating elements are densely arranged. Similarly, if the length of the path Pt2 is shortened, the magnitude of the turn-off surge voltage generated in the switching element Mf2 can be reduced. On the other hand, the physical distance between the switching element Mf2, which is a heating element, and the primary winding Tr12 becomes shorter, and the heating elements are densely arranged.

[0049] Therefore, in the high-voltage power supply unit 120 of the present embodiment, the paths Pt1 and Pt2 are installed as wiring patterns within the printed circuit board. In the present embodiment, by adopting a parallel plate structure obtained by arranging the paths Pt1 and Pt2 having a flat plate structure in parallel with each other using the printed circuit board Sb1, the coupling degree between the primary windings Tr11 and Tr12 is increased, and the leakage inductance between the primary windings Tr11 and Tr12 is reduced. Since the leakage inductance between the primary windings Tr11 and Tr12 can be reduced, the shortening of the distance between the switching elements Mf1 and the primary windings Tr11 and Tr12 can be suppressed, and at the same time, the increase in the magnitude of the generated turn-off surge voltage can also be suppressed. In addition, the path Pt1 can correspond to the "first wiring pattern" of the present disclosure. The path Pt2 can correspond to the "second wiring pattern" of the present disclosure.

[0050] Figure 3 is a top view of the printed circuit board Sb1 in Embodiment 1. The printed circuit board Sb1 is a substrate having a plurality of layers stacked in the Z-axis direction. In addition, in the following description, the normal direction of the printed circuit board Sb1 is defined as the Z-axis direction, and the plane perpendicular to the Z-axis direction is defined as the X-axis and Y-axis. Additionally, the positive direction of the Z-axis in each figure is sometimes referred to as the upper side, and the negative direction is referred to as the lower side. The Z-axis direction can correspond to the "stacking direction" of the present disclosure.

[0051] In the present embodiment, the printed circuit board Sb1 has four layers LyT1, Ly1, Ly2, and LyB1. The layer LyT1 is the layer exposed on the positive side of the Z-axis and is the outermost surface of the printed circuit board Sb1. Figure 3 The upper part shows a view when observing the layer LyT1 from the positive side of the Z-axis. Figure 3 The lower part shows a cross-sectional view of the four layers LyT1, Ly1, Ly2, and LyB1. As Figure 3 shown in the lower part, starting from the positive side of the Z-axis, the layers are arranged in the order of LyT1, Ly1, Ly2, and LyB1. The thickness of each layer in the Z-axis direction is, for example, 1.1 mm. In addition, 1.1 mm is just an example, and the thickness of each layer in the Z-axis direction can be a thickness other than 1.1 mm or can have different thicknesses. Also, the number of layers included in the printed circuit board Sb1 is not limited to four layers and can be, for example, two layers, six layers, etc.

[0052] Referring to Figure 3 the upper part, a transformer 30 is arranged on the positive side of the Y-axis of the printed circuit board Sb1. The ends H1, H3 of the primary winding Tr11 and the ends H2, H4 of the primary winding Tr12 are connected to the printed circuit board Sb1. The switching elements Mf1 and Mf2 are arranged on the negative side of the Y-axis of the printed circuit board Sb1.

[0053] A buffer circuit Sn1 and a buffer circuit Sn2 are mounted on the positive direction side of the Z axis of the layer LyT1 of the printed circuit board Sb1. A conductive wiring pattern is provided inside the printed circuit board Sb1, and the transformer 30 and the switching elements Mf1 and Mf2 are electrically connected through this wiring pattern.

[0054] Next, Figure 4 , Figure 5 layers Ly1 and Ly2, which are arranged on the negative direction side of the Z axis with respect to the layer LyT1, will be described. Figure 4 is a top view of the layer Ly1 included in the printed circuit board Sb1 in Embodiment 1. In the present embodiment, the layer Ly1 is a layer arranged on the negative direction side of the Z axis of the layer LyT1 and is adjacent to the layer LyT1. That is, the layer Ly1 is the second layer from the positive direction side of the Z axis. In addition, the layer Ly1 can correspond to the "first layer" of the present disclosure.

[0055] As Figure 4 shown, a path Pt1 is formed as a wiring pattern on the layer Ly1. The path Pt1 electrically connects the primary winding Tr11 of the transformer 30 and the switching element Mf1. The path Pt1 is connected to the buffer circuit Sn1. The length between the end H1 of the primary winding Tr11 and the switching element Mf1 is a length Ds1.

[0056] Figure 5 is a top view of the layer Ly2 included in the printed circuit board Sb1 in Embodiment 1. In the present embodiment, the layer Ly2 is a layer arranged on the negative direction side of the Z axis of the layer Ly1. The layer Ly2 is adjacent to the layer Ly1 in the stacking direction. That is, the layer Ly2 is the third layer from the positive direction side of the Z axis. In addition, the layer Ly2 can correspond to the "second layer" of the present disclosure.

[0057] As Figure 5 shown, a path Pt2 is formed as a wiring pattern on the layer Ly1. The path Pt2 electrically connects the primary winding Tr12 of the transformer 30 and the switching element Mf2. The path Pt2 is connected to the buffer circuit Sn2. The length between the end H2 of the primary winding Tr12 and the switching element Mf2 is a length Ds2.

[0058] In the present embodiment, Figure 5The shown region Rg1 is the region where path Pt2 overlaps path Pt1 when viewed from the positive Z-axis direction side of the Z-axis. Both path Pt1 and path Pt2 have the shape represented as region Rg1. That is, path Pt1 is configured such that at least a part of path Pt1 overlaps path Pt2 when the printed circuit board Sb1 is viewed from above. In the region represented as region Rg1, the coupling degree of magnetic field coupling between path Pt1 and path Pt2 is increased. Thereby, the mutual inductance between primary winding Tr11 and primary winding Tr12 is improved.

[0059] The mutual inductance between primary winding Tr11 and primary winding Tr12 is improved, that is, the leakage inductance between primary windings Tr11 and Tr12 is reduced, and the loop inductance that is the cause of the turn-off surge voltage is reduced. As a result, in the fluorescence X-ray analysis apparatus 1000 of the present embodiment, it is possible to reduce the turn-off surge voltage while maintaining the distance between the switching element and the primary winding of the transformer. The length Ds1 is, for example, 51 mm, and the length Ds2 is, for example, 43 mm.

[0060] In the present embodiment, with respect to the length Ds1 of 51 mm, the pattern width (length in the X-axis direction) of path Pt1 is, for example, between 7 mm and 10 mm. With respect to the length Ds2 of 43 mm, the pattern width of path Pt2 is, for example, between 7 mm and 10 mm. In addition, the lengths Ds1 and Ds2 and the pattern widths of paths Pt1 and Pt2 are examples, and other sizes may also be used.

[0061] <Comparative Example>

[0062] Next, use Figure 6 、 Figure 7 to illustrate the comparative example. Figure 6 is a top view for explaining paths Pt1Z and Pt2Z in Comparative Example 1. In the following comparative examples, an example in which paths Pt1 and Pt2 in the present embodiment are formed as paths Pt1Z and Pt2Z of cables and not as wiring patterns of the printed circuit board Sb1 will be described.

[0063] In Figure 6 example, the switching element Mf1 and the primary winding Tr11 are connected through path Pt1Z. Path Pt1Z is a cable arranged on the positive Z-axis direction side of the Z-axis of the printed circuit board Sb1. Similarly, the switching element Mf2 and the primary winding Tr12 are connected through path Pt2Z. Path Pt2Z is also a cable arranged on the positive Z-axis direction side of the Z-axis of the printed circuit board Sb1. In addition, in Figure 6The figure shows a path Pt3Z connecting the power supply voltage VCC to the primary winding Tr11 and a path Pt4Z connecting the power supply voltage VCC to the primary winding Tr12. Similar to the paths Pt1Z and Pt2Z, the paths Pt3Z and Pt4Z are cables arranged on the positive Z-axis side of the printed circuit board Sb1.

[0064] In Figure 6 the shown region Rg2, the paths Pt1Z to Pt4Z are twisted together. By twisting the paths Pt1Z to Pt4Z, which are cables, together, the coupling degree between the path Pt1Z and the path Pt2Z is increased compared to the case where the paths Pt1Z to Pt4Z are not twisted. In addition, in the comparative example, first, the path Pt1Z and the path Pt3Z are twisted together, and the path Pt2Z and the path Pt4Z are twisted together. After that, the twisted path Pt1Z and path Pt3Z are further twisted with the twisted path Pt2Z and path Pt4Z. In a comparative example in some aspects, other twisting orders may also be possible.

[0065] However, even in the case where the paths Pt1Z to Pt4Z, which are cables, are twisted together as Figure 6 shown, there are spaces between the cables and insulation covers of the cables. In addition, in the comparative example, the adjacent area of each path per unit length is smaller than that of each path per unit length in Embodiment 1, and in the comparative example, the leakage inductance becomes larger. As a result, the coupling degree between the path Pt1Z and the path Pt2Z in Comparative Example 1 is weaker than the coupling degree between the paths Pt1 and Pt2 that overlap as a wiring pattern as shown in the present embodiment. Therefore, in Comparative Example 1, the length between the switching element Mf1 and the end H1 of the primary winding Tr11 is Ds1 as in the present embodiment, but since the coupling between the paths Pt1 and Pt2 is weaker than in the present embodiment, the generated turn-off surge voltage becomes larger.

[0066] Figure 7 is a top view for explaining the paths Pt1Z and Pt2Z in Comparative Example 2. In Figure 7 the example, similar to Figure 6 the example, the paths Pt1Z and Pt2Z are formed as cables. In Figure 7 the example, the length between the end H1 of the primary winding Tr11 and the switching element Mf1 is the length Ds3. The length Ds3 is shorter than the length Ds1 in the present embodiment.

[0067] As shown in Figure 6As described above, when the paths Pt1Z to Pt4Z are implemented as cables, the mutual inductance between the primary windings Tr11 and Tr12 becomes smaller, and the leakage inductance between the primary windings Tr11 and Tr12 increases compared to the present embodiment. In Figure 7 In the example of, the length of the paths Pt1Z to Pt4Z themselves is shortened, suppressing an increase in the inductance components of the paths Pt1Z and Pt2Z.

[0068] However, in Comparative Example 2, the distance between the transformer 30 and the switching element Mf1 becomes shorter, and the heating elements are densely arranged. Similarly to the transformer 30 and the switching element Mf1, the buffer circuits Sn1 and Sn2 are also heating elements. The buffer circuits Sn1 and Sn2 are arranged near the transformer 30 and the switching elements Mf1 and Mf2. In the comparative example, since the distance between the transformer 30 and the switching element Mf1 is short, the distance between the transformer 30, the switching elements Mf1 and Mf2, and the buffer circuits Sn1 and Sn2 becomes smaller, and a plurality of heating elements become dense.

[0069] When a plurality of heating elements are densely arranged, the temperature of the high-voltage power supply unit 120 may excessively rise due to interaction. In the present embodiment, since the paths Pt1 and Pt2 are implemented using the wiring pattern of the printed circuit board Sb1, it is possible to sufficiently ensure the length Ds1 while suppressing an increase in the inductance components of the paths Pt1 and Pt2.

[0070] As another comparative example, it is also considered to protect the switching elements Mf1 and Mf2 from the turn-off surge voltage by increasing the capacitance of the capacitors included in the buffer circuits Sn1 and Sn2. However, since the capacitance of the capacitors is increased, the power consumed in the buffer circuits Sn1 and Sn2 increases, and the heating of the buffer circuits Sn1 and Sn2 is enhanced. In the present embodiment, since the paths Pt1 and Pt2 are implemented using the wiring pattern of the printed circuit board Sb1, it is possible to reduce the resistance of the buffer circuits Sn1 and Sn2 and the constants of the capacitors, and to reduce the power consumed in the buffer circuits Sn1 and Sn2.

[0071] [Embodiment 2]

[0072] In Embodiment 1, an example in which one transformer 30 is connected to the printed circuit board Sb1 is described. In Embodiment 2, the following structure is described: In addition to connecting the transformer 30, a transformer 30A is also connected to the printed circuit board Sb1. In addition, in Embodiment 2, the structure repeated with the fluorescence X-ray analysis apparatus 1000 of Embodiment 1 will not be described again.

[0073] Figure 8It is a top view of the layer Ly1 included in the printed circuit board Sb1 in Embodiment 2. In Embodiment 2, for the printed circuit board Sb1, in addition to the transformer 30 being connected, a transformer 30A is also connected. Further, for the printed circuit board Sb1, in addition to the switching element Mf1 being connected, a switching element Mf1A is also connected. That is, in Embodiment 2, there are two Figure 2 structures as shown.

[0074] As Figure 8 shown, on the layer Ly1, in addition to the path Pt1, a path Pt1A is also formed as a wiring pattern. The path Pt1A electrically connects the primary winding of the transformer 30A and the switching element Mf1A. That is, the fluorescent X-ray analysis apparatus 1000 of Embodiment 2 includes two transformer primary side circuits 401.

[0075] In addition, in Embodiment 2, the transformer 30 can correspond to the "first transformer" of the present disclosure. In Embodiment 2, the transformer 30A can correspond to the "second transformer" of the present disclosure. In Embodiment 2, the path Pt1 can correspond to the "first wiring pattern of the first transformer" of the present disclosure. In Embodiment 2, the path Pt1A can correspond to the "first wiring pattern of the second transformer" of the present disclosure.

[0076] Figure 9 It is a top view of the layer Ly2 included in the printed circuit board Sb1 in Embodiment 2. As Figure 9 shown, in addition to the path Pt2, a path Pt2A is also formed as a wiring pattern on the layer Ly2. The path Pt2A electrically connects the primary winding of the transformer 30A and the switching element Mf2A. The path Pt2A is connected to the buffer circuit Sn2A.

[0077] In this way, the fluorescent X-ray analysis apparatus 1000 of Embodiment 2 has two transformers. In Embodiment 2, the path Pt1 connected to the transformer 30 and the path Pt1A connected to the transformer 30A are formed on the same layer Ly1. Further, in Embodiment 2, the path Pt2 connected to the transformer 30 and the path Pt2A connected to the transformer 30A are formed on the same layer Ly2. Preferably, the structures and characteristics of the circuit connected to the transformer 30 and the circuit connected to the transformer 30A are the same. In addition, in Embodiment 2, the path Pt2 can correspond to the "second wiring pattern of the first transformer" of the present disclosure. In Embodiment 2, the path Pt2A can correspond to the "second wiring pattern of the second transformer" of the present disclosure.

[0078] [Modified Example]

[0079] In the present embodiment, layer Ly1 and layer Ly2 are adjacent to each other. However, in some aspects, other layers may be provided between layer Ly1 and layer Ly2. Additionally, in the present embodiment, length Ds1 and length Ds2 are different lengths, but they may also be the same length. Further, the shapes of paths Pt1 and Pt2 are not limited to Figure 4 , Figure 5 the shapes shown, and they may also be other shapes.

[0080] Moreover, in the present embodiment, an example is described in which switching elements Mf1 and Mf2 are arranged at different positions in the X-axis direction as Figure 3 shown. However, switching elements Mf1 and Mf2 may also be arranged at different positions in the Z-axis direction or the Y-axis direction.

[0081] In addition, in Embodiment 2, it is also possible that path Pt1 and path Pt1A are formed in different layers, and path Pt2 and path Pt2A are formed in different layers. For example, when printed circuit board Sb1 is formed of four or more layers including the first layer to the fourth layer, path Pt1 may be arranged in the first layer, path Pt2 may be arranged in the second layer, path Pt1A may be arranged in the third layer, and path Pt2A may be arranged in the fourth layer.

[0082] [Mode]

[0083] Those skilled in the art should understand that the above-described multiple exemplary embodiments are specific examples of the following mode.

[0084] (First item) A fluorescence X-ray analysis apparatus (1000) according to one mode includes:

[0085] An X-ray tube (200) including a filament (F1) and a target (Tg1) for irradiating a specimen (S) with primary X-rays (10);

[0086] A detector (300) for detecting secondary X-rays (20) generated from the specimen; and

[0087] A power supply (120) for applying a tube voltage to the target,

[0088] wherein the power supply includes:

[0089] At least one transformer (30);

[0090] A switching circuit (Mf1, Mf2) connected to the primary side of the at least one transformer; and

[0091] A substrate (Sb1) is connected to the switching circuit and the at least one transformer. The substrate (Sb1) has a first layer (Ly1) and a second layer (Ly2).

[0092] Wherein, the at least one transformer includes a first primary winding (Tr11) and a second primary winding (Tr12) on the primary side.

[0093] A first wiring pattern (Pt1) connecting the first primary winding to the switching circuit is formed on the first layer.

[0094] A second wiring pattern (Pt2) connecting the second primary winding to the switching circuit is formed on the second layer.

[0095] The first layer and the second layer are configured such that at least a part of the first wiring pattern overlaps with the second wiring pattern when the substrate is viewed from above in the stacking direction (Z-axis direction).

[0096] According to the fluorescent X-ray analysis device 1000 described in the first item, the distance between the switching element and the primary winding of the transformer can be maintained and the turn-off surge voltage can be reduced.

[0097] (Second item) In the fluorescent X-ray analysis device (1000) described in the first item,

[0098] The first layer is the layer adjacent to the second layer in the stacking direction.

[0099] According to the fluorescent X-ray analysis device 1000 described in the second item, the coupling degree between the path Pt1 and the path Pt2 can be increased.

[0100] (Third item) In the fluorescent X-ray analysis device (1000) described in the first or second item,

[0101] The switching circuit includes:

[0102] A first switching element (Mf1) connected to the first primary winding through the first wiring pattern (Pt1); and

[0103] A second switching element (Mf2) connected to the second primary winding through the second wiring pattern (Pt2).

[0104] According to the fluorescent X-ray analysis device 1000 described in the third item, multiple switching elements can be used to supply power to the transformer 30.

[0105] (Fourth item) In the fluorescent X-ray analysis device (1000) described in the third item,

[0106] The power supply further has:

[0107] A first buffer circuit (Sn1) connected to the first primary winding and the first switching element; and

[0108] A second buffer circuit (Sn2) connected to the second primary winding and the second switching element.

[0109] The fluorescence X-ray analysis apparatus 1000 according to the fourth item can suppress the concentration of heat-generating elements including the buffer circuit.

[0110] (Fifth item) In the fluorescence X-ray analysis apparatus (1000) according to any one of the first to fourth items,

[0111] The at least one transformer includes a first transformer (30) and a second transformer (30A),

[0112] The first wiring pattern (Pt1) at the first transformer (30) and the first wiring pattern (Pt1A) at the second transformer (30A) are formed on the same first layer,

[0113] The second wiring pattern (Pt2) at the first transformer (30) and the second wiring pattern (Pt2A) at the second transformer (30A) are formed on the same second layer.

[0114] In the fluorescence X-ray analysis apparatus 1000 according to the fifth item, since the wiring patterns can be formed on the same layer in a structure having a plurality of transformers, the characteristics of the transformer primary side circuit 401 shown can be made close to the same between the two systems of the transformers. Figure 2 The characteristics of the transformer primary side circuit 401 shown are made close to the same.

[0115] (Sixth item) A power supply device (100) according to one aspect is a power supply device (120) that applies a tube voltage to a target (Tg1) of an X-ray tube (200),

[0116] The power supply device includes:

[0117] At least one transformer (30);

[0118] A switching circuit (Mf1, Mf2) connected to the primary side of the at least one transformer; and

[0119] A substrate (Sb1) connected to the switching circuit and the at least one transformer, and the substrate (Sb1) has a first layer (Ly1) and a second layer (Ly2),

[0120] Wherein, the at least one transformer includes a first primary winding (Tr11) and a second primary winding (Tr12) on the primary side,

[0121] A first wiring pattern (Pt1) that connects the first primary winding to the switching circuit is formed on the first layer.

[0122] A second wiring pattern (Pt2) that connects the second primary winding to the switching circuit is formed on the second layer.

[0123] The first layer and the second layer are configured such that at least a part of the first wiring pattern overlaps with the second wiring pattern when the substrate is viewed from above in the stacking direction (Z-axis direction).

[0124] The power supply device according to Item 6 can maintain the distance between the switching element and the primary winding of the transformer and reduce the turn-off surge voltage.

[0125] The embodiments of the present invention have been described, but it should be considered that the embodiments disclosed this time are examples in all aspects and not restrictive. The scope of the present invention is shown by the claims, and it is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A fluorescent X-ray analysis device, comprising: An X-ray tube, comprising a filament and a target, for irradiating a sample with primary X-rays; a detector that detects secondary X-rays generated from the sample; as well as a power supply that applies a tube voltage to the target, in, The power supply comprises: at least one transformer; a switching circuit connected to the primary side of the at least one transformer; and a substrate connected to the switch circuit and the at least one transformer, the substrate having a first layer and a second layer, wherein the at least one transformer comprises a first primary winding and a second primary winding on the primary side, A first wiring pattern connecting the first primary winding and the switch circuit is formed on the first layer, A second wiring pattern connecting the second primary winding and the switch circuit is formed on the second layer, The first layer and the second layer are arranged such that, when the substrate is viewed in a plan view from a stacking direction, at least a portion of the first wiring pattern overlaps with the second wiring pattern.

2. The fluorescent X-ray analysis device according to claim 1, wherein: The first layer is a layer adjacent to the second layer in the stacking direction.

3. The fluorescent X-ray analysis device according to claim 1 or 2, wherein: The switch circuit comprises: a first switching element connected to the first primary winding through the first wiring pattern; and A second switching element is connected to the second primary winding through the second wiring pattern.

4. The fluorescent X-ray analysis device according to claim 3, wherein: The power supply also has: a first buffer circuit connected to the first primary winding and the first switching element; and The second snubber circuit is connected to the second primary winding and the second switch element.

5. The fluorescent X-ray analysis device according to claim 1 or 2, wherein: The at least one transformer comprises a first transformer and a second transformer, The first wiring pattern at the first transformer and the first wiring pattern at the second transformer are formed on the same first layer, The second wiring pattern at the first transformer and the second wiring pattern at the second transformer are formed on the same second layer.

6. A power supply device for applying a tube voltage to a target disposed in an X-ray tube, the power supply device comprising: at least one transformer; a switching circuit connected to the primary side of the at least one transformer; as well as a substrate connected to the switch circuit and the at least one transformer, the substrate having a first layer and a second layer, wherein the at least one transformer comprises a first primary winding and a second primary winding on the primary side, A first wiring pattern connecting the first primary winding and the switch circuit is formed on the first layer, A second wiring pattern connecting the second primary winding and the switch circuit is formed on the second layer, The first layer and the second layer are arranged such that, when the substrate is viewed in a plan view from a stacking direction, at least a portion of the first wiring pattern overlaps with the second wiring pattern.

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