X-ray inspection device

Abstract

To enable use in high-humidity environments by controlling humidity within a housing of an X-ray inspection device equipped with an air conditioner.SOLUTION: An X-ray inspection device 1 includes within a housing 2, an X-ray detector 4, an air conditioner 5, an air dryer 6 that supplies dry air by supplying compressed air, and flow control means 14 for controlling the flow rate of the dried air exiting the air dryer 6. In a mixing region S provided near the X-ray detector 4, the cold air from the air conditioner 5 and the dried air from the air dryer 6 are mixed to generate air with a humidity lower than that of the cold air, which is then circulated near the X-ray detector.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an X-ray inspection device equipped with an air conditioner, and particularly to an X-ray inspection device that is capable of keeping the internal humidity low even in a high-humidity external environment, thereby making it difficult for condensation to form on electrical components. [Background technology]

[0002] The X-ray inspection apparatus disclosed in Patent Document 1 listed below is an X-ray inspection apparatus 1 that inspects an object 2 by irradiating the object 2 with X-rays 3 that have passed through it, and includes an X-ray detection unit 6 that is disposed in a housing 4 and that is equipped with electrical components that are susceptible to condensation caused by cooling by a cooling means, a humidity sensor 15 that monitors the humidity inside the housing 4, an air conditioner 9 that serves as a cooling means and a dehumidifying means for dehumidifying the inside of the housing 4, and a first control unit 16 that supplies power to a module group when the humidity measured by the humidity sensor 15 is below a predetermined value. In this X-ray inspection apparatus 1, even if the main power is on, if the humidity measured by the humidity sensor 15 is above a predetermined value, the X-ray detection unit 6 that has a module group will not be turned on. Therefore, cooling means such as Peltier elements provided in the module group will not be driven, condensation will not occur on semiconductor chips due to the driving of the Peltier elements, and it is believed that the module group can be prevented from being damaged by water droplets caused by condensation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-179006 Summary of the Invention [Problem to be solved by the invention]

[0004] In X-ray inspection devices used for inspecting products for foreign matter, etc., heat is generated by the operation of various electronic components, including the X-ray source and X-ray detector, etc. If this heat accumulates inside the housing, it may exceed the specified temperature of the electronic components, so it is necessary to cool the inside of the housing to lower the temperature, and even in the X-ray inspection device disclosed in Patent Document 1, an air conditioner is attached to the back side of the housing to cool the inside of the housing.

[0005] Furthermore, some electrical components in X-ray inspection devices are cooled locally using Peltier coolers (Peltier elements) in addition to air conditioners, and in the X-ray inspection device disclosed in Patent Document 1, as described in the embodiment, the semiconductor chip of the X-ray detection unit 6 is cooled by a Peltier element.

[0006] Thus, in an X-ray inspection device, in addition to an air conditioner that cools the inside of the housing, if a Peltier cooler is provided to locally cool specific electronic components (such as an X-ray detector) inside the housing, unless the humidity inside the housing is kept sufficiently low, the humidity inside the housing will increase, causing condensation on the electrical components, increasing the risk of malfunction, especially when the outside humidity is high. Specifically, in cases such as 1) and 2) below, the humidity inside the housing will become particularly high, and condensation may occur on the electronic components that are locally cooled by a Peltier cooler, etc., increasing the risk of malfunction.

[0007] 1) When an air conditioner is in cooling mode, the refrigerant compressed by the compressor vaporizes in the evaporator, causing the air passing through the evaporator to rapidly cool and become cold air, and the temperature difference at this time causes condensation to form on the surface of the evaporator. When the temperature inside the housing reaches the target temperature, the air conditioner's cooling mode stops and the compressor stops, but the fan continues to rotate. The air pushed by the rotating fan is not cooled as it passes through the evaporator, but it becomes mixed with fine condensation water that has adhered to the surface of the evaporator, and as this circulates inside the housing, the relative humidity inside the housing increases.

[0008] 2) When an X-ray inspection device is stopped while in operation, the internal temperature of the device changes from a high state to a low state. During this process, the inside of the housing becomes a negative pressure relative to the outside of the housing, and outside air is sucked in through the drain hose. This causes the relative humidity inside the housing to rise, especially when the humidity of the external environment is high.

[0009] Conventional X-ray inspection devices, including the X-ray inspection device disclosed in Patent Document 1, which are equipped with cooling means for specific electronic components in addition to an air conditioner, were generally thought to be usable at humidity levels of less than about 75%, but could not be used at higher humidity levels due to the problems described in 1) and 2) above.

[0010] The present invention has been made in consideration of the above-described conventional technology and the problems associated with it, and aims to enable an X-ray inspection device with an air conditioner to be used in a high-humidity environment by using an air dryer to control the humidity inside the housing. [Means for solving the problem]

[0011] The X-ray inspection apparatus 1, 1a described in claim 1 comprises: An X-ray inspection apparatus 1, 1a that inspects an object by detecting X-rays that are irradiated onto and transmitted through the object, Case 2 and An X-ray detector 4 disposed inside the housing 2; an air conditioner 5 that supplies cool air to the inside of the housing 2; an air dryer (6) that separates compressed air supplied from outside the housing (2) into dry air and wet air and supplies the dry air to the inside of the housing (2); In a mixing area S provided inside the housing 2 near the X-ray detector 4, the cool air supplied from the air conditioner 5 and the dry air supplied from the air dryer 6 are mixed and supplied to the X-ray detector 4.

[0012] The X-ray inspection apparatus 1, 1a according to claim 2 is the X-ray inspection apparatus 1, 1a according to claim 1, The air dryer 6 is characterized by being provided with a flow rate control means 14 for controlling the flow rate of dry air.

[0013] The X-ray inspection apparatus 1 according to claim 3 is the X-ray inspection apparatus 1 according to claim 2, an electromagnetic valve 31 for controlling the supply of compressed air to the air dryer 6; a humidity switch 32 that operates the solenoid valve 31 in accordance with the humidity inside the housing 2; It is characterized by having:

[0014] The X-ray inspection apparatus 1 according to claim 4 is the X-ray inspection apparatus 1 according to claim 3, The air dryer 6 is characterized by having a pressure adjusting means 30 for adjusting the pressure of the compressed air supplied to the air dryer 6. [Effects of the Invention]

[0015] According to the X-ray inspection device of claim 1, the dry air supplied by the air dryer, which operates independently of the control of the X-ray inspection device, is mixed with the cool air from the air conditioner inside the housing near the X-ray detector, and the air with a lower humidity than the cool air immediately circulates near the X-ray detector, thereby suppressing an increase in humidity near the X-ray detector. This also reduces the risk of harmful condensation forming on electrical components mounted in the X-ray detector and causing malfunctions.

[0016] In particular, when the air conditioner of the X-ray inspection equipment is stopped, the air conditioner fan remains running, causing water droplets adhering to the air conditioner's evaporator to mix with the air sent from the fan, resulting in high-humidity air. However, this air does not pass through the X-ray detector in its high humidity state, and is instead mixed with dry air from the air dryer, so the humidity inside the housing is uniformly kept low.

[0017] Furthermore, even if the X-ray inspection equipment is stopped and the temperature inside the housing drops, the inside of the housing is filled with dry air from the air dryer, creating positive pressure, so humid outside air is not sucked into the housing through the drain hose, etc., and the air inside the housing is kept at a low humidity.

[0018] According to the X-ray inspection device of claim 2, the air dryer is provided with a flow control means so that the flow rate of the dry air supplied into the housing can be set as desired, and therefore the humidity inside the housing can be adjusted so that it does not become excessively low, thereby reducing the risk of static electricity or the like being generated by excessively low humidity, which can cause breakdowns in electrical components.

[0019] According to the X-ray inspection device described in claim 3, the compressed air supplied to the air dryer is controlled by opening and closing a solenoid valve using a humidity switch that operates according to the humidity inside the housing, so that dry air is supplied into the housing only when dehumidification is required, and the solenoid valve stops the supply of dry air when the set humidity is reached. Compared to control using only a flow control means, the flow rate of dry air supplied into the housing is more precisely adjusted according to the humidity inside the housing, further reducing the risk of electrical component failure due to static electricity generated by excessively low humidity. Furthermore, dehumidification only occurs when necessary, which contributes to energy savings.

[0020] According to the X-ray inspection device described in claim 4, a pressure adjustment means is provided to adjust the pressure of the moist air supplied to the air dryer. Therefore, even if the compressed air supplied from outside is higher than the expected value, it can be adjusted to a specified pressure suitable for the air dryer and supplied, thereby achieving a stable drying function. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic diagram showing the concept of the invention in an X-ray inspection apparatus according to a first embodiment. [Figure 2] 1 is a longitudinal sectional view schematically showing the structure of an X-ray inspection apparatus and the flow of air (wind) according to a first embodiment. [Figure 3]FIG. 10 is a schematic diagram showing the concept of the invention in an X-ray inspection apparatus according to a second embodiment. [Figure 4] FIG. 10 is a longitudinal sectional view schematically showing the structure of an X-ray inspection apparatus and the flow of air (wind) according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] A first embodiment of the present invention will be described with reference to FIGS. 1 is a schematic diagram showing the inventive concept of an X-ray inspection apparatus 1 according to a first embodiment. Inside the housing 2 of the X-ray inspection apparatus 1, an X-ray generation source (not shown) and an X-ray detector 4 that detects X-rays that are irradiated onto and transmitted through an object to be inspected are provided. Although not shown, the X-ray detector 4 includes a line sensor made up of a number of semiconductor elements that are electric and electronic components, and a Peltier element that locally cools the line sensor. Because the line sensor is locally cooled by the Peltier element, it can be said that, among the various electric and electronic components inside the housing 2 of the X-ray inspection apparatus 1, it is the component that is most susceptible to condensation due to changes in humidity.

[0023] As shown in FIG. 1, this X-ray inspection device 1 is equipped with an air conditioner 5 that is installed both inside and outside the housing 2 to cool the inside of the housing 2, and an air dryer 6 that is installed inside the housing 2 to supply dry air into the housing 2.

[0024] Although only the evaporator 7 is shown in the air conditioner 5 in Figure 1, this air conditioner 5 is a refrigeration cycle cooling means that has the function of circulating refrigerant between the expansion valve, evaporator 7, compressor, and condenser to cool the warm air inside the housing 2 and supply it as cold air into the housing 2. The air conditioner drain water is discharged outside the housing 2 through a drain hose.

[0025] The cool air that has passed through the evaporator 7 of the air conditioner 5 is air with a relatively high humidity compared to the dry air from the air dryer 6 described below, and is guided by the first air duct 11 and supplied as high-humidity air from the first opening 21 to a mixing area S provided in the housing 2 near the X-ray detector 4. As will be described in detail later, the dry air from the air dryer 6 described above is supplied to this mixing area S and mixed with the cool air from the air conditioner 5 supplied from the first opening 21.

[0026] Although not shown in detail in FIG. 1, the air dryer 6 is a drying means that separates moist compressed air into dry air and wet air. The air dryer 6 is composed of hollow fibers made of a polymer membrane that allows water vapor to pass easily but air to pass through poorly. When moist compressed air is supplied to the inside of the hollow fibers, the difference in water vapor partial pressure between the inside and outside of the hollow fibers causes only the water vapor to pass through the polymer membrane and move to the outside of the hollow fibers. The compressed air from which the moisture has been separated becomes dry air and is discharged from the hollow fibers. Therefore, by continuously supplying compressed air, the function of generating dry air can be continuously performed without using additional energy such as electricity.

[0027] As shown in FIG. 1 , compressed air is sent from a supply source, such as a compressor, outside the housing 2 to the air dryer 6 via a supply pipe 13. The dry air discharged from the air dryer 6 flows into a flow control means 14. The flow control means 14 adjusts the flow rate of the dry air discharged from the air dryer 6. Although not shown, the flow rate can be preset to any desired value using an adjustment means, such as a rotary adjustment knob. The dry air flow rate set in the flow control means 14 can be determined based on the results of tests conducted by the manufacturer of the X-ray inspection apparatus 1 before shipment, in which the X-ray inspection apparatus 1 is actually operated. Specifically, the dry air flow rate can be set so that the humidity level inside the housing 2 is sufficient for the X-ray inspection apparatus 1 to operate without any problems. If the humidity inside the housing 2 becomes excessively low, static electricity may be generated, potentially causing damage to electrical components. However, by appropriately setting the flow control means 14 in advance, such problems can be prevented.

[0028] 1, one end of the second air duct 12 is connected to the outlet of the flow rate control means 14, and the other end, the second opening 22, is located in the aforementioned mixing area S. This mixing area S is supplied with cool air (high humidity air) from the air conditioner 5 through the first opening 21 and with dry air from the air dryer 6 through the second opening 22, and the two airs are mixed together to produce air with a lower humidity than the cool air from the air conditioner 5, which immediately flows near the X-ray detector 4. For this reason, condensation does not form on the line sensor and the like that is locally cooled by the Peltier element and is mounted on the X-ray detector 4, and there is little risk of the X-ray detector 4 malfunctioning.

[0029] In Fig. 1, the other ends of the first air duct 11 and the second air duct 12 are parallel to each other and lined up close to each other, and the first opening 21 and the second opening 22 are oriented in the same direction and face the X-ray detector 4. However, because Fig. 1 is a schematic diagram illustrating the concept of the invention, such an arrangement is not necessarily required. In short, it is sufficient that the area near the X-ray detector 4, which has an X-ray detection element that is susceptible to humidity due to a limited operating humidity range, is made into a mixing region S, which is a space for mixing dry air and cool air (high humidity air), and that the first opening 21 and the second opening 22 are arranged in this region, so that the air mixed in the mixing region S flows to the X-ray detector 4 immediately after mixing.

[0030] Fig. 2 is a vertical cross-sectional view showing the structure and air (wind) flow of the X-ray inspection apparatus 1 of the first embodiment more specifically and in more detail than Fig. 1. In Fig. 2, components that are the same as or correspond to those in Fig. 1 are given the same reference numerals as in Fig. 1, and the explanation of Fig. 1 is used to avoid repetition.

[0031] As shown in FIG. 2, the housing 2 of the X-ray inspection apparatus 1 is composed of an upper housing 2a that houses an X-ray generation source, a lower housing 2c that houses an X-ray detector 4, and an intermediate housing 2b on the rear side (right side in FIG. 2) that connects the upper housing 2a and the lower housing 2c. The space outside the housing 2, between the upper housing 2a and the lower housing 2c and on the front side (left side in FIG. 2) of the intermediate housing 2b, is an inspection space where an object to be inspected is irradiated with X-rays. In reality, a transport means for transporting an object to be inspected in a direction perpendicular to the plane of the page in FIG. 2 is provided at the bottom of the inspection space (above the lower housing 2c). This inspection space is shielded from the outside world by a shielding structure and shielding means (not shown).

[0032] As shown in Fig. 2, an air conditioner 5 is provided on the rear side of the housing 2. The air conditioner 5 in Fig. 2 shows a condenser 8, a fan 15, and a drain hose 16 as its main components, but this air conditioner 5 is a cooling means of a refrigeration cycle with the same functions as the air conditioner 5 shown in the conceptual diagram of the invention in Fig. 1, and also includes other components necessary for the refrigeration cycle.

[0033] As shown in Figure 2, the warm air inside the housing 2 that has returned from the X-ray generation source 3 and the X-ray detector 4 to the air conditioner 5 passes through the evaporator 7 of the air conditioner 5 (see Figure 1) to become cool air, and is then returned into the housing 2 by the fan 15 of the air conditioner 5. The cool air is supplied to the X-ray generation source 3 through an upper flow path 17 provided inside the housing 2, and is also carried to the mixing region S through a lower flow path 18 provided inside the housing 2. Note that air conditioner drain water contained in the high-humidity air from the condenser 8 is discharged to the outside of the housing 2 through a drain hose 16.

[0034] The lower flow path 18 in Fig. 2 corresponds to the first blower duct 11 in Fig. 1. A first opening 21 is provided at the lower end of the lower flow path 18, and the first opening 21 is arranged horizontally opposite a mixing area S provided at the rear bottom of the lower housing 2c.

[0035] As shown in Figure 2, an air dryer 6 is provided inside the intermediate housing 2b. Compressed air supplied to the air dryer 6 is sent from a supply source such as a compressor outside the housing 2 through a supply pipe 13 provided to penetrate the housing 2. The dried air discharged from the air dryer 6 flows into a flow rate control means 14. One end of a second air duct 12 is connected to the outlet of the flow rate control means 14. The other end of the second air duct 12 extends vertically, and a second opening 22 at the other end is disposed above the mixing region S facing downward.

[0036] As shown in Fig. 2, a fan 19 is provided between the mixing area S and the X-ray detector 4, with the air blowing direction facing the X-ray detector 4. Into this mixing area S, cool air from the air conditioner 5 is supplied horizontally forward from a first opening 21, and dry air from the air dryer 6 is supplied vertically downward from a second opening 22. By mixing the two airs, air with a lower humidity than the cool air from the air conditioner 5 is produced and blown toward the X-ray detector 4 by the fan 19. For this reason, condensation does not form on the line sensors and the like mounted on the X-ray detector 4 that are locally cooled by Peltier elements, and there is little risk of malfunction.

[0037] In Fig. 2, the airflow direction (horizontal direction) at the lower end of the first air duct 11 (downward flow path 18) and the airflow direction (vertical direction) at the other end of the second air duct 12 are perpendicular to each other, and both airflow directions intersect in the mixing region S. Therefore, the dry air and the cool air, which has a higher humidity than the dry air, collide in directions perpendicular to each other in the mixing region S, and are quickly and uniformly mixed. Moreover, the mixed air is sucked into the fan 19 and forcibly transported toward the X-ray detector 4, so that the mixed air is blown toward the X-ray detector 4 in a more uniformly mixed state.

[0038] According to the X-ray inspection apparatus 1 of the first embodiment, dry air is supplied from an air dryer 6 that operates using compressed air supplied from an external source, independent of the control of the X-ray inspection apparatus 1. This dry air is mixed with cool air from an air conditioner 5 in a mixing area S set up inside the housing 2 near the X-ray detector 4, and the resulting air has a lower humidity than the cool air and flows near the X-ray detector 4. Therefore, for example, humidity can be kept within the operating humidity range for a direct conversion X-ray detector using a semiconductor element, which has a limited operating humidity (30 to 75% at room temperature). Furthermore, even if a Peltier cooler for localized cooling is provided, there is little risk of harmful condensation forming on electrical components mounted on the X-ray detector 4 and causing a malfunction.

[0039] Even when the air conditioner 5 is stopped, the fan 15 of the air conditioner 5 is still running, so the water droplets adhering to the evaporator 7 mix with the air sent from the fan 15 of the air conditioner 5 to generate high-humidity air. However, this air is mixed with the dry air from the air dryer 6, so the humidity inside the housing 2 is kept low and uniform.

[0040] Furthermore, even if the X-ray inspection device 1 is stopped and the internal temperature of the housing 2 drops, the inside of the housing 2 is under positive pressure due to the dry air from the air dryer 6, so that humid external air is not sucked into the housing 2 through the drain hose 16.

[0041] A second embodiment of the present invention will be described with reference to FIGS. Fig. 3 is a schematic diagram showing the concept of the invention in an X-ray inspection apparatus 1a of a second embodiment, and Fig. 4 is a vertical cross-sectional view showing the structure of the X-ray inspection apparatus 1a of the second embodiment and the flow of air (wind) more specifically and in more detail than Fig. 3. In the following explanation, the parts that differ from the first embodiment will be mainly explained, and for the components in Figs. 3 and 4 that are the same as or correspond to those in Figs. 1 and 2, the description of the first embodiment will be cited to avoid repetition of explanation.

[0042] 3 and 4, supply pipe 13 connected to a supply source such as a compressor (not shown) outside housing 2 is led into housing 2 (middle housing 2b) and connected to air dryer 6. Inside housing 2 (middle housing 2b), pressure adjustment means 30 and solenoid valve 31 are connected to supply pipe 13 just before air dryer 6, in that order from the side closest to air dryer 6.

[0043] The pressure adjusting means 30 is a device called a regulator that adjusts the pressure of the compressed air supplied to the air dryer 6 to a constant pressure that is specified for each model of the air dryer 6.

[0044] The solenoid valve 31 is a switching device that controls the ON / OFF of the supply of compressed air to the pressure adjusting device 30 and is driven using the power supply of the X-ray inspection apparatus 1a. The solenoid valve 31 is switched by a humidity switch 32. As shown in FIG. 4 , the humidity switch 32 is located in the path of the warm air returning from the X-ray detector 4 to the air conditioner 5 (in FIG. 4 , at the top of the intermediate housing 2b, near the inlet of the condenser 8 of the air conditioner 5). The humidity switch 32 measures the humidity of the warm air returning from the X-ray detector 4, and when this humidity is below the set humidity (i.e., when the humidity is sufficiently low), the humidity switch 32 turns OFF, shutting off the solenoid valve 31 and stopping the flow of compressed air into the air dryer 6, preventing the inside of the housing 2 from becoming excessively dry. Note that instead of providing the humidity switch 32, a similar effect can be achieved by controlling the solenoid valve 31 ON / OFF at an appropriate predetermined cycle.

[0045] In the X-ray inspection apparatus 1 of the first embodiment shown in FIGS. 1 and 2 , the internal environment of the housing 2 can be dehumidified by operating the air dryer 6. However, depending on the flow rate of dry air, it may take a considerable amount of time for the interior of the housing 2 to dry. Therefore, when using the X-ray inspection apparatus 1 of the first embodiment in a high-humidity environment, a long time may be required to lower the humidity inside the housing 2 before starting the operation. In reality, however, such a long time is not desirable for startup preparations. Therefore, in order to quickly dry the interior of the housing 2 in the X-ray inspection apparatus 1 of the first embodiment in a short period of time, the flow rate of dry air must be increased. However, this ultimately results in a low relative humidity when the apparatus is saturated, resulting in a humidity low enough to pose a risk of static electricity generation. Reducing the flow rate of dry air can change the saturated humidity inside the housing 2, but this makes it impossible to quickly dry and dehumidify the interior of the housing 2.

[0046] Therefore, in order to further improve the performance and functions of the first embodiment, the X-ray inspection apparatus 1a of the second embodiment is provided with a humidity switch 32 that monitors the relative humidity inside the apparatus, and when the humidity falls below a predetermined level, the solenoid valve 31 shuts off the passage of compressed air supplied to the air dryer 6, thereby controlling the inside of the apparatus so as not to dry out too much. In this case, the humidity inside the apparatus can be adjusted to a predetermined value, and there is no need to dehumidify during cooling operation of the air conditioner 5, so the air dryer 6 stops, which also has the effect of reducing running costs.

[0047] According to the X-ray inspection apparatus 1a of the second embodiment, the compressed air supplied to the air dryer 6 is controlled by opening and closing the solenoid valve 31 using the humidity switch 32 which operates in accordance with the humidity inside the housing 2, and dry air is supplied into the housing 2 only when dehumidification is required, and the supply of dry air is stopped when the set humidity is reached.Therefore, compared to the first embodiment which is controlled only by the flow control means 14, the flow rate of dry air supplied into the housing 2 is more precisely adjusted in accordance with the humidity inside the housing 2, further reducing the risk of electrical components breaking down due to static electricity, etc. generated by excessively low humidity.

[0048] Furthermore, since the pressure of the compressed air (high humidity air) supplied to the air dryer 6 is adjusted by the pressure adjusting means 30, even if the compressed air supplied from outside is unexpectedly high pressure or if the pressure suddenly increases for some reason, the pressure can be reduced to the specified pressure of the air dryer 6 and supplied, thereby achieving stable drying function. [Explanation of symbols]

[0049] 1, 1a...X-ray inspection equipment 2. Housing 4...X-ray detector 5. Air conditioner 6...Air dryer 14...Flow rate control means 30...Pressure adjusting means 31...Solenoid valve 32...Humidity switch S…Mixed area

Claims

1. An X-ray inspection apparatus (1, 1a) for inspecting an object by detecting X-rays irradiated onto and transmitted through the object, A housing (2), an X-ray detector (4) disposed inside the housing; an air conditioner (5) that supplies cool air to the inside of the housing; an air dryer (6) that separates compressed air supplied from outside the housing into dry air and wet air and supplies the dry air to the inside of the housing; An X-ray inspection device (1, 1a), characterized in that in a mixing area (S) provided inside the housing near the X-ray detector, cool air supplied from the air conditioner and dry air supplied from the air dryer are mixed and supplied to the X-ray detector.

2. 2. The X-ray inspection apparatus (1, 1a) according to claim 1, wherein the air dryer (6) is provided with a flow rate control means (14) for controlling the flow rate of dry air.

3. a solenoid valve (31) for controlling the supply of compressed air to the air dryer (6); a humidity switch (32) that operates the solenoid valve in accordance with the humidity inside the housing; 3. An X-ray examination device (1a) according to claim 2, characterized in that it comprises:

4. 4. The X-ray inspection apparatus (1a) according to claim 3, further comprising a pressure adjusting means (30) for adjusting the pressure of the compressed air supplied to the air dryer (6).

Images