WO2006025320A1

WO2006025320A1 - X-ray source

Info

Publication number: WO2006025320A1
Application number: PCT/JP2005/015651
Authority: WO
Inventors: Michihiro Ito; Kazutaka Suzuki
Original assignee: Hamamatsu Photonics K.K.
Priority date: 2004-09-02
Filing date: 2005-08-29
Publication date: 2006-03-09
Also published as: CN1994027A; CN1994027B; JP2006073381A; JP4664025B2

Abstract

Disclosed is an X-ray source (1) comprising a high-voltage power supply unit (17), an X-ray tube (27), a metal cylinder (29) projecting from the high-voltage power supply unit (17) and surrounding the X-ray tube (27), and a casing (3) housing the high-voltage power supply unit (17) and the metal cylinder (29). The casing (3) is provided with a cooling fan (55a) for causing a cooling wind to flow around the metal cylinder (29) within the casing (3), thereby efficiently cooling the metal cylinder (29) which contains the X-ray tube (27) that is heated to high temperature.

Description

X-ray source

Technical field

The present invention particularly relates to an X-ray source used as a microfocus X-ray source.

Background art

Conventionally, a microfocus X-ray source (manufactured by Hamamatsu Photonics Co., Ltd., product number L9181S) described in Non-Patent Document 1 is known as a technology in such a field. This microfocus X-ray source is a type of X-ray source equipped with an X-ray tube that collides electrons from an electron gun with a target and irradiates the generated X-rays to the outside through an irradiation window. This microfocus X-ray source is used in an X-ray non-destructive inspection device that detects abnormalities in an inspection object based on an X-ray transmission image transmitted through the inspection object.

Non-Patent Document 1: Microfocus X-ray source series, Hamamatsu Photonics Co., Ltd., April 2004, p. 1

Disclosure of the invention

Problems to be solved by the invention

However, with this type of microfocus X-ray source, the higher the output, the greater the heat generated from the X-ray tube during operation. When the temperature of the X-ray tube becomes high, the output decreases accordingly. Therefore, if it is intended to stably increase the output of the X-ray source, it is necessary to cool the X-ray tube efficiently. In the above X-ray source, the X-ray tube force heat is easily dissipated by a structure that exposes the X-ray tube surrounding portion that accommodates the X-ray tube from the housing for storing the control board and the like. In addition, as one way to further increase the cooling efficiency, the X-ray tube is cooled during operation by sending cooling air to the exposed X-ray tube enclosure by an external cooling fan. .

[0004] However, in this case, the cooling air of the cooling fan power diffuses and it is difficult to concentrate the cooling air on the X-ray tube surrounding portion, so that the X-ray tube can be sufficiently cooled. Natsuki. In addition, since the X-ray tube is not evenly cooled, the output is unstable. It was difficult to achieve a stable high output of this X-ray source.

[0005] When the output of the X-ray source is low, the amount of X-ray irradiation is small, so in the case of an X-ray nondestructive inspection device, a clear transmission image cannot be obtained, and high-precision inspection is difficult. It is. In particular, when inspecting objects to be inspected on the transfer line at high speed, it is necessary to set the time during which X-rays can be irradiated as short as possible, so it is clear when the output of the X-ray source is low. I could not get a clear transmission image.

[0006] Therefore, an object of the present invention is to provide an X-ray source that stably achieves high output.

Means for solving the problem

[0007] In order to solve the above problems, the X-ray source of the present invention includes a high piezoelectric source part molded with an insulating material, and X-rays generated by the electric power of the high-voltage power supply part and irradiated to the outside. A tube, an X-ray tube enclosure that protrudes and surrounds at least a part of the X-ray tube, a housing that houses the high-voltage power supply unit and the X-ray tube enclosure, And a cooling fan for allowing cooling air to flow around the X-ray tube surrounding portion.

[0008] In this X-ray source, the cooling air generated by the cooling fan flows in the housing, so that the cooling air can be efficiently and evenly distributed around the X-ray tube enclosure. . The cooling air removes heat from the X-ray tube enclosure.

[0009] Further, the casing extends in a direction substantially orthogonal to the first wall having an irradiation window for irradiating the X-ray generated by the X-ray tube to the outside of the casing, and is cooled. It is preferable to have a second wall on which the fan is disposed, and an inclined wall that crosses the first wall and the second wall and connects the two. In this case, by using the inclined wall as the wall connecting the first wall and the second wall, the inclined wall has a function of guiding the airflow generated by the cooling fins.

[0010] Further, it is preferable to further include a cooling fin provided on the outer periphery of the X-ray tube surrounding portion. The cooling fins expand the heat transfer area between the X-ray tube enclosure and the cooling air flowing around it, increasing the amount of heat transfer.

[0011] A control unit that houses a control unit that controls the X-ray generation unit, an X-ray generation unit that includes at least a high-voltage power supply unit, an X-ray tube, and an X-ray tube surrounding unit, and a cooling fan are located within the housing. It may be further provided with a partition wall that partitions the space. As a result, the circulation of the air that has become hot air by cooling the high-voltage power supply unit and the X-ray tube enclosure is suppressed. [0012] Preferably, the partition wall is disposed between the X-ray tube surrounding portion and the control portion, and has a vent hole that communicates the partitioned space. In this case, a part of the air introduced by the cooling fan is circulated around the control unit while suppressing the inflow of warm air. Alternatively, the partition wall may block communication between the divided spaces. In this case, the space in which the X-ray generation unit is accommodated is isolated from the space around the control unit, and the flow of mutual airflow is blocked.

[0013] A second cooling fan arranged on the space side where the control unit of the casing is arranged may be further provided. The second cooling fan mainly has a function of cooling the control unit.

The invention's effect

[0014] According to the present invention, the heat generated in the X-ray tube is efficiently removed through the X-ray tube surrounding portion by efficiently cooling the X-ray tube surrounding portion with the cooling air. In other words, since the X-ray tube can be cooled efficiently, the X-ray source can have a stable and high output.

[0015] When the case is provided with an inclined wall, the inclined wall can generate a smooth flow of cooling air in the case, and as a result, the X-ray tube enclosure can be efficiently cooled. .

[0016] When cooling fins are provided on the outer periphery of the X-ray tube surrounding portion, the amount of heat transfer from the X-ray tube surrounding portion to the cooling air can be increased, and the X-ray tube surrounding portion can be efficiently cooled. .

[0017] By providing the partition wall inside the housing as described above, the partition wall prevents the cooling air (hot air) that has become hot after cooling the X-ray generation unit from flowing toward the control unit. Therefore, the temperature rise of the control unit can be suppressed. As a result, the operation of the control unit can be stabilized.

[0018] When the above-described ventilation port is provided in the partition wall, it is possible to suppress the cooling air that has become high temperature after cooling the X-ray tube surrounding portion from flowing directly into the control unit, and at the same time, the cooling fan As a result, a part of the cooling air generated can be introduced to the control unit through the air vent, which contributes to the cooling of the control unit and can further stabilize the operation of the control unit.

On the other hand, when the X-ray generation unit and the control unit are separated from each other by the partition wall, the cooling air can be intensively flowed around the X-ray generation unit, and the cooling can be performed intensively.

[0020] When the second cooling fan is provided on the control unit side, the control unit is concentrated by the second cooling fan. Can be cooled.

Brief Description of Drawings

FIG. 1 is a perspective view showing a first embodiment of an X-ray source according to the present invention.

FIG. 2 is a front view of the X-ray source shown in FIG.

3 is a cross-sectional view of the X-ray generation part of the X-ray source shown in FIG.

4 is a cross-sectional view of the control unit of the X-ray source shown in FIG.

FIG. 5 is a front view showing a second embodiment of the X-ray source according to the present invention.

FIG. 6 is a perspective view showing a third embodiment of the X-ray source according to the present invention. Explanation of symbols

[0022] 1, 71, 91 X-ray source

3, 73 housing

3c Upper wall (first wall)

3b Side wall (second wall)

3d inclined wall

3j aperture (irradiation part)

5 X-ray generator

7 Control unit

15 Partition wall

17 High voltage power supply

27 X-ray tube

29a Cooling fin

29 Metal tube (X-ray tube enclosure)

55a, 77a cooling fan

59 Ventilation openings

75 partition wall

Rl X-ray generator housing space

R2 control space

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same reference numerals are given to the same components in the drawings as much as possible, and duplicate descriptions are omitted.

(First embodiment)

FIG. 1 is a perspective view showing a first embodiment of an X-ray source according to the present invention, and FIG. 2 is a front view thereof. As shown in Fig. 1 and Fig. 2, X-ray source 1 is an X-ray type equipped with an X-ray tube that collides electrons from an electron gun with a target and irradiates the generated X-rays to the outside through an irradiation window. For example, it is used as an X-ray source in an X-ray nondestructive inspection apparatus. An X-ray generation unit 5 that generates and irradiates X-rays and a control unit 7 that controls the X-ray generation unit 5 are stored in the housing 3 of the X-ray source 1. The internal space of the housing 3 is composed of an X-ray generation unit accommodating space R1 for accommodating the X-ray generation unit 5, a control unit accommodating space R2 for accommodating the control unit 7, and a force. A partition wall 15 extending downward from the upper inner wall of the housing 3 is provided between the space R1 and the control unit accommodation space R2. That is, the partition wall 15 divides the X-ray generation unit accommodation space R1 and the control unit accommodation space R2.

As shown in FIG. 3, a cross-sectional view of the X-ray generation unit 5 includes a high voltage power supply unit 17 fixed to the bottom plate 3a of the housing 3 and the supply of electric power from the high voltage power supply unit 17. An X-ray tube 27 for irradiating X-rays and a metal tube (X-ray tube surrounding portion) 29 surrounding a part of the X-ray tube 27 are provided. The high voltage power supply unit 17 includes a high voltage transformer 19 that can generate a high voltage, a high voltage supply circuit 23 that multiplies the high voltage generated by the high voltage transformer 19 and supplies the high voltage to the X-ray tube 27, a high voltage transformer 19 A conducting wire 25a that electrically connects the pressure supply circuit 23 and a conducting wire 25b that electrically connects the high-pressure supply circuit 23 and the X-ray tube 27 are provided. The high-voltage supply circuit 23 and the conductive wires 25a and 25b are molded in an insulating block 21 made of an electrically insulating material (for example, epoxy resin), and the high-voltage transformer 19 It is provided on the side surface 21 so as to protrude to the control unit 7 side. Such a structure of the high-voltage power supply unit 17 prevents discharge from the high-voltage supply circuit 23 to which a high voltage is applied and the conductive wires 25a and 25b to the outside.

[0026] The X-ray tube 27 located above the high-voltage power supply unit 17 is a reflective target type X-ray tube, and holds a rod-shaped anode 27b in an insulated state and accommodates a valve unit 27a. A target accommodating portion 27d that accommodates a target 27c provided at an end of the rod-shaped anode 27b; An electron gun unit 27e that houses an electron gun 27k that emits an electron beam toward the reflecting surface of the target 27c.

[0027] The valve portion 27a and the target accommodating portion 27d are arranged coaxially, and the axis of the electron gun portion 27e is substantially orthogonal to the axis. The base end portion of the rod-shaped anode 27b protrudes downward from the lower portion of the valve portion 27a as the high voltage application portion 27g.

[0028] A socket 33 is connected to the lower portion of the high voltage application unit 27g, and the socket 33 is electrically connected to the high voltage supply circuit 23 via the conductor 25b of the high voltage power supply unit 17. With such a configuration, a high voltage is supplied to the X-ray tube 27 from the high voltage supply circuit 23 via the conductor 25b. When the X-ray tube 27 receives a high voltage and the electron gun 27k in the electron gun unit 27e emits electrons toward the target 27c, X-rays are generated from the target 27c. The object is irradiated from the X-ray irradiation window 27h provided in the opening of the target container 27d.

Note that the X-ray tube 27 is a sealed type, and the inside thereof is sealed in a vacuum. For example, the X-ray tube 27 is provided with an exhaust pipe (not shown), and after the inside of the valve portion 27a, the target accommodating portion 27d and the electron gun portion 27e is evacuated, the exhaust pipe is connected to the X-ray tube 27. It is sealed by sealing.

The metal tube 29 is provided so as to protrude upward from the upper surface of the high-voltage power supply unit 17 and is formed in a cylindrical shape surrounding the X-ray tube 27. In order to efficiently dissipate the heat generated from the X-ray tube 27, the metal tube 29 is made of a metal with excellent heat dissipation (for example, aluminum) and is provided with a plurality of cooling fins 29a extending in the horizontal direction around the metal tube 29. ing. The cooling fin 29a is provided as a protruding portion extending in the circumferential direction on the circumferential surface of the metal tube 29, and increases the surface area of the metal tube 29, and efficiently dissipates heat generated from the X-ray tube 27. Can do.

[0031] An opening 2¾ is formed at the front end surface of the metal tube 29, and a valve portion 27a of the X-ray tube 27 is inserted from the opening 2¾. A liquid electrical insulating material is inserted into the internal space of the metal tube 29. Insulating oil 31 is injected. A mounting flange 27f is formed between the valve portion 27a and the target accommodating portion 27d of the X-ray tube 27, and the X-ray tube 27 is fixed to the distal end surface of the metal tube 29 by the mounting flange 27f. The lev 27a is immersed in the insulating oil 31. By adopting this insulating oil 31, the valve part 27a of the X-ray tube 27 is insulated. The outer discharge from the X-ray tube 27 is prevented.

Next, the control unit 7 will be described. FIG. 4 is a cross-sectional view of the control unit 7. As shown in FIGS. 1 and 4, the control unit 7 is provided in the control unit accommodating space R2, and has a first circuit board 35, a second circuit board 37, and a drive power supply unit 39. The first circuit board 35 controls the voltage that can be generated by the high-voltage power supply unit 17 from a high voltage (for example, 160 kV) to a low voltage (for example, OV). Further, the first circuit board 35 controls the emission timing, tube voltage, tube current and the like of the electron gun section 27e. The second circuit board 37 controls the operation of the first circuit board 35 based on a control signal of external force. The drive power supply unit 39 is a converter that performs ACZDC conversion (or DCZDC conversion) on electric power supplied also from an external force. The drive power supply unit 39 supplies drive power to the first circuit board 35 and the second circuit board 37, and X-rays. Electric power for generating a high voltage is supplied to the high-voltage transformer 19 of the generator 5. Note that the first circuit board 35, the second circuit board 37, the drive power supply unit 39, and the X-ray generation unit 5 are appropriately electrically connected to each other by a conductor (not shown).

[0033] In the control unit 7, the first circuit board 35, the second circuit board 37, and the drive power supply unit 39 are accommodated in the force control unit accommodation space R2 in a compact manner and can be securely fixed. It is preferable. For this reason, the control unit 7 is provided with a circuit board holder 49 having a heat conductive metal (for example, aluminum) force in the control unit accommodating space R2, and the circuit board holder 49 includes the first circuit board 35 and the first circuit board 35. 2 The circuit board 37 and the drive power supply 39 are supported.

The circuit board holder 49 includes a first plate (first member) 45 and a second plate (second member) 47 that also have a thermally conductive metal force. The first plate 45 has a first flat plate portion 46 that is inclined and inclined with respect to the bottom plate 3a, and the second plate 47 is a second flat plate that is erected substantially perpendicular to the bottom plate 3a. Part 48. The lower ends of the first plate 45 and the second plate 47 are fixed to the bottom plate 3a by screws 49a, and the upper ends of the plates 45 and 47 are overlapped with each other by screws (an example of fastening means) 49b. And

The first flat plate portion 46 has a first mounting surface 45a for mounting the first circuit board 35, and the second flat plate portion 48 is a second plate for mounting the second circuit board 37. It has a mounting surface 47b and a third mounting surface 47c which is the back surface of the second mounting surface 47b. Circuit board By forming the rudder 49 in a chevron structure, the circuit boards 35 and 37 attached to the circuit board holder 49 can be securely fixed to the bottom plate 3a while maintaining the mechanical strength of the circuit board holder 49 itself.

[0036] The lower portion of the second plate 47 is bent in an L shape so as to approach the side wall 3f of the housing 3, and the high voltage transformer 19 of the high voltage power supply unit 17 includes the second plate 47 and the first plate. It is located between 45.

The first circuit board 35 is attached along the first attachment surface 45 a of the first plate 45 via the spacer 51. Similarly, the second circuit board 37 is mounted along the second mounting surface 47b of the second plate 47 via the spacer 51, and the drive power supply unit 39 is mounted on the third mounting surface 47c of the second plate 47. And is attached via a spacer 51.

[0038] Since the first mounting surface 45a of the circuit board holder 49 is provided to be inclined with respect to the bottom plate 3a, the first circuit board 35 can be accommodated in the control unit accommodating space R2 while being inclined. Contributes to the low profile of X-ray source 1. In addition, since the circuit board holder 49 is composed of two members, the first plate 45 and the second plate 47, the circuit boards 35 and 37 and the drive are mounted on the first to third mounting surfaces 45a, 47b and 47c. After mounting the power supply unit 39, the drive power supply unit 39 is arranged between the first plate 45 and the second plate 47 by connecting the first plate 45 and the second plate 47 by screwing, and the circuit board holder Since 49 can be completed, the assembling workability of the control unit 7 is improved.

[0039] In such an X-ray source 1, since the X-ray tube 27 generates heat during operation, the X-ray tube 27 and the metal tube 29 are likely to become hot. The heat generated by the X-ray tube 27 increases as the output of the X-ray irradiation increases. When the temperature of the X-ray tube 27 increases, other parts are adversely affected and the output of the X-ray tube 27 is reduced. Therefore, it is necessary to efficiently cool the metal tube 29 in order to cool the X-ray tube 27 efficiently.

Therefore, in the X-ray source 1, as shown in FIG. 1, the X-ray generation unit 5 including the metal tube 29 is stored inside the housing 3 and is orthogonal to the bottom plate 3 a of the housing 3. A cooling fan unit 55 is provided on the side wall (second wall) 3b that stands up and the metal tube 29 is cooled by flowing cooling air in the housing 3.

[0041] As shown in FIGS. 1 and 4, the housing 3 extends in parallel with the bottom plate 3a, and has an X-ray tube. It has an upper wall (first wall) 3c provided with an opening (irradiation part) 3 for irradiating the X-rays from 27 to the outside. This opening is provided at a position corresponding to the irradiation window 27h of the X-ray tube 27 and exposes the irradiation window 27h to the outside. Further, in the housing 3, a wall connecting the upper wall 3c and the side wall 3b is formed as an inclined wall 3d. Further, the wall connecting the side wall 3f facing the side wall 3b and the upper wall 3c is also an inclined wall 3e. The degree of inclination of the inclined wall 3d and the inclined wall 3e with respect to the upper wall 3c may be different or the same.

The cooling fan unit 55 is provided on the side wall 3b of the housing 3 as described above, and includes the cooling fan 55a that rotates about an axis perpendicular to the side wall 3b. The cooling fan 55a rotates to cause air to flow from the outside to the inside of the housing 3. The cooling fan 55a is positioned in the vicinity of the X-ray generation unit 5 so that the cooling air directly hits the X-ray generation unit 5.

[0043] The air taken into the housing 3 by the cooling fan 55a flows in the X-ray generation unit accommodating space R1 as cooling air, and hits the metal cylinder 29 without unevenness. While passing, it flows in the direction of the side wall 3f. Then, the cooling air passing around the metal tube 29 is guided by the cooling fins 29a and smoothly flows in the horizontal direction, hits the metal tube 29 with a sufficient heat transfer area, and efficiently heats from the metal tube 29. Remove it. As a result, the metal tube 29 can be efficiently cooled, and the X-ray tube 27 surrounded by the metal tube 29 can be efficiently cooled. Since the metal tube 29 contacts the cooling air without any unevenness and is cooled, it is possible to suppress output fluctuation and output decrease due to temperature unevenness of the X-ray tube 27. Thereafter, the cooling air that has received heat from the metal tube 29 and has risen in temperature is discharged to the outside through the exhaust port 3k provided in the inclined wall 3e.

[0044] At this time, since the wall connecting the upper wall 3c and the side wall 3b is the inclined wall 3d, the stagnation of the cooling air is suppressed and a smooth flow of the cooling air in the housing 3 appears. It can be made. As a result, the cooling air smoothly flows around the metal tube 29, and the metal tube 29 can be efficiently cooled. Since the wall connecting the upper wall 3c and the side wall 3f of the housing 3 is also the inclined wall 3e, this also contributes to the smooth flow of the cooling air. As described above, the X-ray source 1 can efficiently cool the X-ray tube 27 by efficiently cooling the metal tube 29, so that the output of the X-ray source can be increased.

Note that the X-ray source 1 is connected to a personal computer or the like on a part of the side wall 3b on the control unit accommodation space R2 side. The X-ray source 1 inputs and outputs signals relating to the control information of the personal computer force and the like via the connector portion. Of the casing 3 excluding the bottom plate 3a, the cooling fan unit 55 and the connector section (not shown) have wiring connections to the control section 7 and the like, so that they are separate from other parts of the casing 3. If it is, it is preferable in terms of maintenance of the X-ray source 1 or the like. In the present embodiment, the cooling fan unit 55 and the connector portion (not shown) are fixed to the bottom plate 3a and connected to the control portion 7 by wiring.

[0046] It should be noted that since the inclined wall 3d and the inclined wall 3e are formed in the casing 3 of the X-ray source 1, the following effects can be obtained. When the inclined walls 3d and 3e are not formed, corners are formed between the upper wall 3c and the side walls 3b and 3f. Here, when obtaining a fluoroscopic image in which the inspection object is tilted with such an X-ray source, the tilted inspection object hits the corner, and therefore the irradiation window 27h and the inspection object are sufficiently close to each other. I can't let you. In contrast, in the X-ray source 1, since such a corner does not exist, the inspection object can be brought closer to the irradiation window 27h. For this reason, it is possible to obtain a fluoroscopic image of the inspection object having a larger magnification.

In such an X-ray source 1, various electronic components are mounted on the first and second circuit boards 35 and 37 and the drive power supply unit 39 of the control unit 7. In order to stabilize the operating characteristics of each part, it is necessary to cool these parts. In particular, the drive power supply unit 39 generates a large amount of heat when performing ACZDC conversion (or DCZDC conversion), and thus needs to be efficiently cooled.

[0048] Therefore, the partition wall 15 in the housing 3 does not completely separate the X-ray generation unit accommodation space R1 and the control unit accommodation space R2, but separates the partition between the metal tube 29 and the control unit 7. Below the wall 15, there is provided a ventilation port 59 that communicates the X-ray generation unit accommodation space R 1 and the control unit accommodation space R 2. Thus, since the metal tube 29 and the control unit 7 are partitioned by the partition wall 15, the cooling air that has become hot after cooling the metal tube 29 flows directly into the control unit accommodating space R2. Can be suppressed. Further, it is possible to suppress that the radiant heat generated from the metal cylinder 29 is blocked by the partition wall 15 and directly transmitted to the control unit 7. As a result, the temperature rise of the control unit 7 can be suppressed, and the operation of the circuit boards 35 and 37 of the control unit 7 can be stabilized. At the same time, the X-ray generation unit accommodating space R1 and the control unit accommodating space R are formed by the vent 59. Therefore, a part of the cooling air introduced by the cooling fan 55a flows into the control unit accommodating space R2 through the ventilation port 59, so that the control unit 7 can be cooled by this cooling air. it can.

[0049] At this time, since the circuit board holder 49 is configured as described above, as shown in FIG. 4, the control unit housing space R2 includes the first plate 45, the second plate 47, the bottom plate 3a, and the like. Tunnel part R2a surrounded by is formed. This tunnel portion R2a extends in the direction in which the cooling air flows in through the ventilation opening 59 (the direction perpendicular to the paper surface of FIG. 4), and thus functions as a cooling air ventilation path. Therefore, a smooth cooling air flow that concentrates on the tunnel R2a occurs. Since the drive power supply unit 39 exists in the tunnel portion R2a, the heat generated in the drive power supply unit 39 is efficiently removed by the cooling air, and the drive power supply unit 39 is cooled intensively and efficiently. can do. As a result, the operation characteristics of the drive power supply 39 can be stabilized.

[0050] In addition, the high-voltage transformer 19 is provided so as to protrude from the insulating block 21 in the direction of the control unit 17, and is located in the tunnel part R2a. Therefore, the high-voltage transformer 19 is also provided in the tunnel part R2a. Will come into contact with the flowing cooling air (see Fig. 2). Therefore, the high-pressure transformer 19 that reaches a high temperature is also efficiently cooled by the cooling air. Then, the cooling air that has received heat from the drive power supply unit 39 and the high-voltage transformer 19 and has risen in temperature is discharged to the outside through the exhaust port 3h (see FIGS. 1 and 2) provided in the side wall 3g of the housing 3. Is done.

[0051] At this time, a part of the cooling air that has flowed into the control unit housing space R2 through the ventilation opening 59 also flows into the space R2b outside the circuit board holder 49, and this outside space R2b Since the first circuit board 35 and the second circuit board 37 exist in the configured ventilation path, the circuit boards 35 and 37 are cooled by the cooling air flowing in the space R2b.

[0052] In this way, the cooling air that cools the first circuit board 35 and the second circuit board 37 and the cooling air that cools the drive power supply unit 39 and the high-voltage transformer 19 flow in different ventilation paths, respectively. Therefore, the circuit board holder 49 prevents the cooling air from being mixed. As a result, the drive power supply 39 and the high-voltage transformer 19 that generate a large amount of heat are efficiently cooled, while cooling air whose temperature has risen due to cooling of the drive power supply 39 and the high-voltage transformer 19 flows into the tunnel R2a. The temperature of the first circuit board 35 and the second circuit board 37 However, it can suppress that it rises on the contrary. As a result, the operating characteristics of the components of the first circuit board 35 and the second circuit board 37 can be stabilized.

It should be noted that the first circuit board 35, the second circuit board 37, and the drive power supply unit 39 are mounted in a state of being lifted from the mounting surfaces 45a, 47b, 47c via the spacers 51. Therefore, the cooling air comes into contact with both the front and back of the first circuit board 35, the second circuit board 37, and the drive power supply unit 39. Therefore, such a mounting method also contributes to good efficiency and cooling of the first circuit board 35, the second circuit board 37, and the drive power supply unit 39.

In addition, among the components of the first circuit board 35, the power transistor 61 (see FIG. 2) generates a relatively large amount of heat, so that it is separated from the first circuit board 35, and the high voltage power supply unit 17 and the cooling fan are separated. It is installed in close contact with a metal heat sink 63 provided between the knit 55. At this time, the power transistor 61 functions as a component of the first circuit board 35 by being electrically connected to the first circuit board 35 by a conducting wire (not shown). With such an arrangement, the heat sink 63 is cooled by receiving the cooling air from the cooling fan 55a, and the power transistor 61 tightly attached to the heat sink 63 is indirectly cooled. In this way, the temperature rise of the control unit 7 can be effectively suppressed by separately cooling components that generate particularly large heat away from the circuit board body side force.

(Second embodiment)

As shown in the front view of FIG. 5, the X-ray source 71 of the second embodiment of the present invention includes a housing 73. A partition wall 75 that partitions the X-ray generation unit accommodation space R1 and the control unit accommodation space R2 is formed in the case 73 so as to extend from the inner wall of the case 73. That is, the internal space of the housing 73 is divided into the X-ray generation unit accommodation space R1 and the control unit accommodation space R2 by the partition wall 75, and cooling air flows into and out of the two spaces. It is isolated so as not to. According to such a configuration of the X-ray source 71, the cooling fan 55a allows the cooling air to flow into the X-ray generation unit accommodating space R1 to intensively cool the X-ray generation unit 5 including the metal tube 29. In addition, it is possible to reliably prevent the cooling air that has become hot from flowing into the control unit accommodating space R2.

In addition, the X-ray source 71 includes a second cooling fan unit 77 different from the cooling fan unit 55 on the control unit accommodation space R 2 side of the housing 73. This cooling fan unit 77 and other cooling units The cooling fan 77a is arranged in the vicinity of the first circuit board 35 so that the cooling air generated by the cooling fan 77a directly hits the first circuit board 35. With such a configuration, the cooling fan 55a causes the cooling air to flow into the X-ray generation unit accommodating space R1 and cools the X-ray generation unit 5 in the middle, and at the same time, the cooling fan 77a controls the control unit accommodating space R2. The cooling air can be flowed into the controller 7 to cool the controller 7 in a concentrated manner. In this way, by individually cooling the X-ray generation unit accommodating space R1 and the control unit accommodating space R2, the X-ray generation unit 5 including the metal tube 29 and the control unit 7 including the drive power supply unit 39 are efficiently performed. Can be cooled. In this case, it is preferable that the metal heat sink 63 for cooling the power transistor 61 and the power transistor 61 is disposed in the vicinity of the cooling fan 77a in the control unit accommodating space R2, since the cooling efficiency is increased.

[0057] As described above, the X-ray source 71 can also efficiently cool the X-ray tube 27 by efficiently cooling the metal tube 29. Therefore, the output of the X-ray source can be increased, and the control unit By efficiently cooling the drive power supply unit 39 of 7, the operation characteristics of each component of the drive power supply unit 39 can be stabilized.

(Third embodiment)

FIG. 6 shows a perspective view of the control unit 7 in the X-ray source 91 of the third embodiment of the present invention via a circuit board holder 85 including plates 81 and 83 that are independent from each other. The circuit boards 35 and 37 are fixed to the bottom plate 3a. Also with such an X-ray source 91, the drive power supply 39 is efficiently cooled by the cooling air flowing in the space between the plate 81 and the plate 83. The plates 81 and 83 may extend until reaching the upper wall 3c and contact the upper wall 3c.

Note that the present invention is not limited to the above embodiment. For example, in the above embodiment, the cooling fan 55a, 77a uses an intake-type cooling fan that sends air from the outside to the inside of the casing as the cooling fan 55a, 77a. It may be an exhaust type that sends out. In this case, the cooling fans 55a and 77a are preferably arranged close to the heat source.

In addition, the arrangement of the cooling fan 55a is not limited to the side wall 3b, and may be provided in another part as long as the cooling air flows inside the housing 3 around the metal tube 29. For example The cooling air may flow around the metal tube 29 by providing a ventilation hole in the casing 3 and disposing a cooling fan in the vicinity of the ventilation opening and in the casing 3.

[0061] In addition, a plurality of cooling fans may be provided in each of the X-ray generation unit accommodation space R1 and the control unit accommodation space R2. In this case, an intake-type cooling fan and an exhaust-type cooling fan can be provided in combination. For example, in addition to the cooling fan 55a on the side wall 3b of the X-ray generation unit accommodating space R1, an exhaust type cooling fan can be provided on the substantially opposite wall (particularly the inclined wall 3e). Further, for example, in addition to the cooling fan 77a on the side wall 3b of the control unit housing space R2, an exhaust type cooling fan can be provided on the substantially opposing wall (particularly the side wall 3f) or the side wall 3g.

[0062] If the X-ray generation unit accommodation space R1 and the control unit accommodation space R2 are not partitioned, an intake-type cooling fan is provided in the X-ray generation unit accommodation space R1 to accommodate the control unit. Exhaust type cooling fan may be provided on the space R2 side. Exhaust type cooling fan may be provided on the X-ray generation unit accommodation space side R1, and intake type cooling fan may be provided on the control unit accommodation space R2 side. Good. For example, when a cooling fan is provided in the control unit housing space R2 in addition to the intake-type cooling fan 55a on the X-ray generation unit housing space R1, the air in the tunnel unit R 2a having the drive power supply unit 39 is smoothly discharged outside the housing. An exhaust type cooling fan may be placed on the side wall 3g so that it can be sent to the side.

[0063] Further, the X-ray tube 27 may be a transmissive target type that is not a reflective target type. The X-ray tube 27 may be accommodated entirely in the metal tube 29. In this case, the X-ray tube 27 has a high X-ray permeability in order to irradiate the X-ray from the X-ray tube to the outside. A site can be provided. Further, a part of the X-ray tube 27 may protrude from the metal tube 29 and further protrude from the housing 3. The metal tube 29 surrounding the X-ray tube 27 may not be provided with the cooling fin 29a.

[0064] Further, the circuit board holder 49 is not limited to being screwed, and may be fixed to the bottom plate 3a by welding or adhesion. Further, the circuit board holder 49 may be fixed to a member fixed to the casing 3 which may be fixed to a portion other than the bottom plate 3a of the casing 3. Further, the first plate 45 and the second plate 47 are not limited to being screwed but may be connected by welding or adhesion. The circuit board holder 49 is also composed of a single member, a first plate 45 and a second plate 47. Not only the holder but also a number of members may be combined. In this case, the bending process can be omitted by forming a circuit board holder by combining a number of members such as flat plates. The circuit board holder 49 is not limited to a heat conductive metal, and may be made of resin.

[0065] Further, the respective configurations described above can be combined with each other without departing from the gist of the present invention.

Industrial applicability

[0066] The X-ray source according to the present invention is suitable as a microfocus X-ray source used in, for example, an X-ray nondestructive inspection apparatus.

Claims

The scope of the claims

[1] a high voltage power supply molded with an insulating material;

An X-ray tube that generates X-rays by the electric power of the high-voltage power supply unit and irradiates the X-ray tube; and an X-ray tube enclosure that protrudes from the high-voltage power supply unit and surrounds at least a part of the X-ray tube. ,

A housing for storing the high-voltage power supply unit and the X-ray tube surrounding unit;

An X-ray source comprising: a cooling fan that causes cooling air to flow around the X-ray tube surrounding portion inside the housing.

[2] The housing is

A first wall having an irradiation window for irradiating X-rays generated by the X-ray tube to the outside of the housing; and a second wall extending in a direction substantially orthogonal to the first wall and the cooling fan being disposed. The wall of the

The X-ray source according to claim 1, further comprising an inclined wall that intersects the first wall and the second wall and connects the two.

3. The X-ray source according to claim 1, further comprising cooling fins provided on an outer periphery of the X-ray tube surrounding portion.

[4] A control unit that houses a control unit that controls the X-ray generation unit in the housing, an X-ray generation unit having at least the high-voltage power supply unit, the X-ray tube, and the X-ray tube surrounding unit, 4. The X-ray source according to claim 1, further comprising a partition wall that partitions the space where the cooling fan is located.

5. The partition wall according to claim 4, wherein the partition wall is disposed between the X-ray tube surrounding portion and the control portion, and has a ventilation port communicating with the partitioned space. X-ray source.

6. The X-ray source according to claim 4, wherein the partition wall blocks communication between the divided spaces.

[7] The displacement according to any one of claims 4 to 6, further comprising a second cooling fan disposed on a space side where the control unit of the housing is disposed. X-ray source.