X-ray inspection equipment

Abstract

To provide an X-ray inspection device that prevents condensation on electrical components caused by the cold air from an air conditioner, thereby suppressing failure of electrical components. [Solution] An X-ray inspection apparatus 1 that inspects an object to be inspected 2 by detecting X-rays 3 transmitted through the object to be inspected 2 comprises an X-ray detection unit 6 arranged inside a housing 4 for detecting the X-rays 3, an air conditioner 9 for cooling the inside of the housing 4, and a first dehumidification means and a second dehumidification means for dehumidifying the inside of the housing 4.

Description

Technical Field

[0001] The present invention relates to an X-ray inspection apparatus.

Background Art

[0002] Conventionally, an X-ray inspection apparatus has been used to detect foreign substances (such as metal, bone, glass, stone, synthetic resin materials, etc.) in various types of inspection objects (including the surface), such as raw meat, fish, processed foods, and pharmaceuticals. In an X-ray inspection apparatus, heat is generated by driving various electronic components, including an X-ray source and an X-ray detector. If this heat accumulates inside the housing, it may exceed the specified temperature of the electronic components (for example, 40°C). Therefore, it is necessary to cool the inside of the housing to lower the temperature. In the X-ray inspection apparatus disclosed in Patent Document 1, an air conditioner (AC) is attached to the back surface of the housing, and the inside of the housing is cooled by its cooling unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] X-ray inspection equipment has various configurations for cooling the X-ray source and X-ray detector, and some are equipped with air conditioners as described above. By equipping the equipment with an air conditioner, it becomes unnecessary to take in outside air, and the temperature rise caused by the heat emitted from the electrical units that make up the X-ray inspection equipment can be suppressed while maintaining waterproof and dustproof properties in the environment in which it is used. In addition, the dehumidification function of the air conditioner can dehumidify the inside of the equipment. However, when the air conditioner controls the cooling function to maintain a constant temperature and then stops, when the air conditioner stops, the humidity inside the equipment rises due to the inflow of vaporized air from water droplets remaining in the air conditioner's evaporator into the equipment, and the intrusion of high-humidity outside air into the equipment through the air conditioner's drain hose. When the air conditioner then restarts operation, water droplets may adhere to the surface of electrical components that make up the electrical units inside the equipment, such as semiconductor chips, which can cause malfunctions.

[0005] The present invention has been made in view of the above circumstances, and its purpose is to provide an X-ray inspection apparatus that can prevent localized condensation on and around the surface of electrical components that may occur due to a temperature drop caused by a cooling means for cooling the inside of a device such as an air conditioner, and can suppress failure of electrical components. [Means for solving the problem]

[0006] Next, means for solving the above-mentioned problems will be described with reference to drawings corresponding to the embodiments. The X-ray inspection apparatus 1 according to claim 1 of the present invention is an X-ray inspection apparatus 1 that inspects an object to be inspected 2 by detecting X-rays 3 that are irradiated onto the object to be inspected 2 and transmitted through it, An X-ray detection unit 6 is located inside the housing 4 and detects the X-rays 3, An air conditioner 9 for cooling the inside of the enclosure 4, A first dehumidifying means and a second dehumidifying means for dehumidifying the inside of the housing 4, It is characterized by having the following features.

[0007] In this X-ray inspection apparatus 1, the inside of the housing 4 is cooled by an air conditioner 9, and the inside of the housing 4 is dehumidified by a first dehumidifying means and a second dehumidifying means. As a result, the X-ray inspection apparatus 1 can prevent localized condensation on electrical components due to cooling means such as the air conditioner 9, and suppress failure of electrical components.

[0008] The X-ray inspection apparatus 1 according to claim 2 of the present invention is the X-ray inspection apparatus 1 according to claim 1, The first dehumidifying means is characterized by being the dehumidifying function of the air conditioner 9.

[0009] In this X-ray inspection apparatus 1, even when the function of the air conditioner 9 is used to switch between cooling and dehumidifying the housing 4 to dehumidify the housing 4, the second dehumidification means can reliably dehumidify the housing 4 without being affected by the operation of the air conditioner 9.

[0010] The X-ray inspection apparatus 1 according to claim 3 of the present invention is the X-ray inspection apparatus 1 according to claim 1 or claim 2, The second dehumidifying means is characterized by being a dehumidifier 20 specifically for dehumidification.

[0011] In this X-ray inspection device 1, a dehumidifier 20 is used exclusively for dehumidification, so the inside of the housing 4 can be dehumidified without being affected by the operation of the air conditioner 9. Furthermore, by designing the dehumidifier to operate independently of the inspection device control, the inside of the housing 4 can be dehumidified without being affected by the operation of the X-ray inspection device 1.

[0012] The X-ray inspection apparatus 1 according to claim 4 of the present invention is the X-ray inspection apparatus 1 according to claim 3, The second dehumidifying means is characterized by being located near the X-ray detection unit 6.

[0013] In this X-ray inspection apparatus 1, when the cooling means such as a Peltier element provided in the module group in the X-ray detection unit 6 is driven, water droplets due to condensation are likely to adhere to the semiconductor chip. However, since the dehumidifier 20 is disposed in the vicinity of the X-ray detection unit 6, it is possible to avoid the humid state of the X-ray detection unit 6 and suppress the failure of the module group in the X-ray detection unit 6.

[0014] The X-ray inspection apparatus 1 according to claim 5 of the present invention is the X-ray inspection apparatus 1 according to claim 3, characterized in that the second dehumidifying means is disposed on the air guiding path of the X-ray detection unit 6.

[0015] In this X-ray inspection apparatus 1, since the high-humidity air from the X-ray detection unit 6 is arranged to pass through the dehumidifier 20, moisture can be efficiently removed and discharged outside the housing. As a result, it is possible to avoid the humid state of the X-ray detection unit 6 and suppress the failure of the module group in the X-ray detection unit 6.

Advantages of the Invention

[0016] It is possible to prevent local condensation on the surface and around of the electrical components that may occur due to the temperature drop caused by the cooling means for cooling the inside of the apparatus such as an air conditioner, and suppress the failure of the electrical components.

Brief Description of the Drawings

[0017] [Figure 1] It is a side view of the housing part of the X-ray inspection apparatus according to the embodiment.

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. FIG. 1 is a side view of the X-ray inspection apparatus 1 according to the embodiment. The X-ray inspection apparatus 1 according to the present embodiment inspects the object to be inspected 2 by detecting the X-ray 3 that has been irradiated to and transmitted through the object to be inspected 2. Examples of the object to be inspected 2 include raw meat, fish, processed foods, pharmaceuticals, and the like.

[0019] The X-ray inspection apparatus 1 includes an X-ray source 5 that generates X-rays 3, an X-ray detection unit 6 that receives the X-rays 3 from the X-ray source 5, and a conveying means 7 that conveys the object to be inspected 2 between the X-ray source 5 and the X-ray detection unit 6, in a housing 4. When the X-ray inspection apparatus 1 is used in an inspection process of a production line for foods, drugs, etc., for example, when the object to be inspected 2 is sequentially carried in from an upstream manufacturing process or processing process and a predetermined inspection is repeatedly performed, the inspection result is displayed on an operation panel 17 and a signal is output to other devices. The inspected object to be inspected 2 is sequentially carried out to a downstream sorting process or packaging process.

[0020] In the present embodiment, the housing 4 includes an upper housing A that houses the X-ray source 5, a lower housing B that houses the X-ray detection unit 6, and a back housing C that connects the upper housing A and the lower housing B on the back side of the X-ray inspection apparatus 1 so as to form an irradiation region for irradiating the object to be inspected 2 with the X-rays 3, and is supported by legs D.

[0021] The X-ray source 5 irradiates the object to be inspected 2 conveyed by the conveying means 7 having a conveying belt that circulates and moves with the X-rays 3. The X-ray source 5 has a tank, and is configured to house an X-ray tube that becomes an X-ray source by filling the tank with cooling oil. The tank cooling unit provided on the upper surface of the tank has heat radiation fins 8 covered with a cover. The X-ray source 5 is disposed in the upper housing A of the housing 4 and irradiates the X-rays 3 downward. The X-rays 3 are irradiated in a substantially conical shape that spreads downward from the X-ray tube, and then become a planar shape that spreads downward through a long hole formed at the bottom of the X-ray source 5. In the X-ray source 5, heat generated when the X-rays 3 are generated is radiated by the heat radiation fins 8.

[0022] The X-ray detection unit 6 is located within the lower housing B of the housing 4 and below the conveyor belt, and detects X-rays 3 that have passed through the object to be inspected 2. The X-ray detection unit 6 has a slit that allows the planar X-rays 3 irradiated from the X-ray source 5 to pass through. The X-rays 3 that have passed through the slit are received by the sensor portion of the X-ray detection unit 6. In the sensor portion, the semiconductor chip, which is the detection element, is locally cooled by a Peltier element. The X-ray detection unit 6 converts these X-rays 3 into light and outputs it to an X-ray processing unit (not shown).

[0023] The housing 4 is equipped with an air conditioner 9 at its rear as a means of cooling. The air conditioner 9 has a refrigeration cycle. Specifically, the air conditioner 9 has a cooling function that cools the inside of the housing 4 by passing air circulating inside the housing 4 through an evaporator, and a dehumidifying function that dehumidifies the inside of the housing 4 by passing a weak stream of air through the evaporator and draining the condensed water generated in the evaporator.

[0024] The air conditioner 9 has a built-in temperature sensor and a controller that turns on the cooling operation when the temperature reaches the high-temperature setting temperature based on the output of this sensor, and turns off the cooling operation when the temperature reaches the low-temperature setting temperature. This controller can also switch between the cooling operation and dehumidification operation of the air conditioner 9.

[0025] The cooling performance of this air conditioner 9 is set based on the volume of the space to be cooled and the maximum temperature rise determined by the amount of heat generated within that space, or a unit with a predetermined cooling performance is selected. In particular, when the heat generated by the X-ray source 5 is large and high cooling performance is required, a large air conditioner 9 is installed in the rear housing C of the housing 4.

[0026] The housing 4 has an upper branch duct 10 that supplies air (cold air) from the air conditioner 9 outlet to the X-ray source 5 in the upper housing A, and a lower branch duct 11 that supplies air to the X-ray detection unit 6 in the lower housing B. The air supplied from the air conditioner 9 to the X-ray source 5 and the X-ray detection unit 6 is returned to the intake port of the air conditioner 9 through an intake duct 14 located in a return chamber 13 defined by a partition plate 12 within the housing 4, and circulates within the housing 4, thereby cooling both the X-ray source 5 and the X-ray detection unit 6.

[0027] Inside the housing 4, various electrical components are arranged as multiple electrical units. Among these are modules equipped with electrical components that have low durability against water droplet adhesion, i.e., are susceptible to condensation. Examples of these modules include line sensor units equipped with semiconductor chips used in the X-ray detection unit 6. The line sensor unit is also susceptible to heat, meaning it has a narrow operating temperature range, and its maximum operating temperature, which defines the upper limit of the operating temperature, is about 20°C to 30°C lower than that of other electrical units. Therefore, a Peltier element is provided in contact with the semiconductor chip as a cooling means for the line sensor unit, and it mainly dissipates heat locally from the semiconductor chip by thermal conduction, suppressing temperature rise and protecting it from heat. The strength of the cooling performance of such a localized cooling means is set based on the amount of heat generated by the electrical component to be cooled and its operating temperature range, or a means with a predetermined cooling performance is selected. For example, when a small cooling means such as a Peltier element is selected, the low-temperature surface of the Peltier element is brought into contact with the electrical component, absorbing heat from the contact surface, and heat is transferred to the high-temperature surface. The temperature rise of the high-temperature surface is diffused and dissipated within the X-ray detection unit 6 by the circulation of air from the air conditioner 9.

[0028] The X-ray inspection apparatus 1 is equipped with a humidity sensor 15 that monitors the humidity inside the housing 4. This humidity sensor 15 is located in a space affected by the temperature drop caused by the cooling of the Peltier element, which is a local cooling means, and is preferably placed in the lower part of the lower housing B or the rear housing C of the housing 4, near the X-ray detection unit 6, where a group of modules containing electrical components that are susceptible to condensation are located. This allows for accurate detection of high humidity conditions that are prone to condensation, which can lead to failure of the X-ray detection unit 6.

[0029] The X-ray inspection apparatus 1 is equipped with a dehumidification means for dehumidifying the inside of the housing 4. In this embodiment, this dehumidification means is realized by the dehumidification operation, which is the dehumidification function of the air conditioner 9 described above. In addition to the dehumidification operation by the evaporator of the air conditioner 9 (first dehumidification means), a dehumidifier 20 dedicated to dehumidification is provided as a second dehumidification means near the X-ray detection unit 6 inside the housing 4 and on the air guide path. The air guide path is the space inside the housing 4 and includes the return chamber 13. As a result, when the air conditioner 9 is stopped, water droplets remaining in the evaporator can be condensed by the dehumidifier 20, so that condensed water accumulated during the operation of the air conditioner does not remain in the evaporator, and the rise in humidity after the cooling operation of the air conditioner 9 is stopped can be suppressed. Furthermore, by arranging the dehumidifier 20 near the X-ray detection unit 6, the air in the X-ray detection unit 6 can be efficiently dehumidified, and the dehumidified air is drawn into the evaporator of the air conditioner 9, which can more effectively suppress the rise in humidity when the air conditioner 9 is stopped. Furthermore, because the dehumidifier 20 is located on the airflow path of the X-ray detection unit 6, it can efficiently remove moisture from inside the housing 4 and discharge it outside the housing 4. The drain water from the air conditioner 9 and the dehumidifier 20 is discharged outside the housing 4 via a drain hose (not shown).

[0030] The X-ray inspection apparatus 1 includes a first control unit 16. The first control unit 16 includes a central processing unit (CPU), a memory unit, connection ports and communication interfaces for various sensors, etc. The first control unit 16 controls the supply of power to the module group when the humidity detected by the humidity sensor 15 is below a predetermined value, or controls the supply of power to the module group when the detected humidity is above a predetermined value. An operation panel 17, which is located on the front of the housing 4, is connected to the first control unit 16.

[0031] Within the housing 4, separate from the modules susceptible to condensation, there is a group of modules that are not affected by condensation, that is, have a structure that is less prone to failure due to condensation, or are less susceptible to condensation itself (referred to as the non-condensing module group). An example of the non-condensing module group is the X-ray source 5, which houses electrical components in a metal case filled with insulating oil and also serves as a heat source. The X-ray inspection device 1 is also equipped with a temperature sensor that monitors the temperature inside the housing 4. This temperature sensor is provided in multiple locations, such as near heat-generating units like the X-ray source 5, and near the operation panel 17 which has heat-sensitive electrical components, and is connected to the first control unit 16. A high-temperature alarm may be output if the temperature exceeds a predetermined reference value.

[0032] The first control unit 16 outputs control signals to the module group. These control signals are, for example, voltage signals defined as high or low levels, and in other examples, command signals that transmit and receive predetermined commands via serial communication. Such control signals include power control signals that control the power supply to each electrical unit. By switching off a switch using this power control signal, the power supplied to a specific electrical unit can be cut off.

[0033] The first control unit 16 may, after starting the irradiation of the X-ray source 5 with X-rays, perform control to start the cooling function of the air conditioner 9 if the temperature measured by the temperature sensor (not shown) is above a predetermined value.

[0034] Furthermore, the X-ray inspection device 1 includes a second control unit 18. The second control unit 18 controls communication with external devices, etc., and works in cooperation with the first control unit to send and receive electrical signals to and from other devices and higher-level management systems according to the operating status and inspection results of the X-ray inspection device 1.

[0035] The control of the X-ray inspection apparatus 1 by the first control unit 16 begins when the main power is turned on upon starting the apparatus. The control program stored in the memory unit is then loaded into the central processing unit (CPU), and the startup sequence begins. During the startup sequence, each electrical unit is initialized, and the outputs of various sensors, such as humidity and temperature sensors, are collected, and a warm-up operation begins. This warm-up operation stabilizes the operating temperature of the electrical units, suppresses changes in electrical characteristics dependent on temperature changes, and stabilizes performance. To shorten the warm-up time, a warm-up heater with a fan may be provided.

[0036] When the warm-up operation is complete, the first control unit 16 enters a standby state for inspection, and the inspection can be started by operating the operation panel 17. When the operation panel 17 is operated to start the inspection, it irradiates the X-ray generating means 5 with X-rays of a predetermined intensity and outputs an operation start signal to a controller (not shown) to start the operation of the transport means 7, thereby operating the motor as the drive source. When the transport means 7 starts operating, the second control unit 18 outputs a signal to other equipment and higher-level management systems indicating that the X-ray inspection device 1 is ready for inspection.

[0037] The X-ray inspection device 1 inspects the objects 2 that are brought in sequentially. The inspection results are displayed on the control panel 17 and output from the second control unit 18 to other equipment and a higher-level management system.

[0038] Next, when the temperature detected by the temperature sensor exceeds a predetermined value, for example, when the intensity of the irradiated X-rays 3 is high and the ambient temperature rises rapidly due to heat generated from the X-ray source 5, the first control unit 16 turns on the cooling operation of the air conditioner 9 to suppress the rise in temperature inside the housing 4. The first control unit 16 also compares the value detected by the humidity sensor 15 with a preset threshold. At this time, if the humidity detected by the humidity sensor 15 is higher than the threshold, i.e., high humidity, in order to suppress the occurrence of condensation, the first control unit 16 first turns on the dehumidification operation of the air conditioner 9 to lower the humidity without lowering the temperature inside the housing 4, and dehumidifies the inside of the housing 4. Then, the first control unit 16 compares the value detected by the humidity sensor 15 with the threshold, and when the detected humidity inside the housing 4 becomes lower than the threshold, it stops the dehumidification operation of the air conditioner 9 and turns on the cooling operation.

[0039] Furthermore, while the air conditioner 9 is dehumidifying, that is, while a high humidity state is detected by the humidity sensor 15, the first control unit 16 outputs a power control signal to cut off the power supply to the module group prone to condensation, and also outputs a high humidity alarm to stop the X-ray inspection.

[0040] Then, after stopping the X-ray inspection, the first control unit 16 stops the signals indicating that inspection is possible for the other equipment before and after it. Once the high humidity condition is gone due to the dehumidification operation of the air conditioner 9, power is turned on again to the module group prone to condensation and inspection begins.

[0041] The first control unit 16 should switch between cooling operation and dehumidification operation of the air conditioner 9, taking into account the values ​​detected by the temperature sensor and the humidity sensor 15. For example, if the temperature detected by the temperature sensor is below the operating start temperature of the air conditioner 9 and the humidity detected by the humidity sensor 15 is high, dehumidification operation is performed, and if both temperature and humidity are high, cooling operation is performed.

[0042] Furthermore, both the cooling and dehumidifying operations of the air conditioner 9 have a dehumidifying effect because water vapor is liquefied and discharged in the heat exchanger. Therefore, even if the air conditioner 9 does not have a dehumidifying function, the first control unit 16 may, based on the value detected by the humidity sensor 15, prioritize the suppression of condensation in the module group over the temperature rise inside the housing 4, which is a condition requiring cooling operation, when controlling the air conditioner 9. If the threshold is set to, for example, 60% relative humidity, the first control unit 16 monitors the humidity and turns on the power to the module group when the relative humidity falls below 60%. If the relative humidity exceeds 60%, it turns off the power to the module group.

[0043] Here, we will describe an example in which the X-ray inspection device 1 is installed in a meat processing line where washing using high-temperature steam is routinely performed.

[0044] When the ambient temperature is 30°C and the relative humidity is 80%, the absolute humidity is approximately 0.022 kg / kg(DA) according to the psychrometric chart. The amount of water vapor in the air at this time is approximately 22 g / m³. 3 This corresponds to the following: When the dehumidifying function of air conditioner 9 brings the temperature inside enclosure 4 to 25°C and the relative humidity to 60%, the absolute humidity will be approximately 0.012 kg / kg(DA) according to the psychrometric chart. The amount of water vapor in the air at this time is approximately 12 g / m³. 3 This corresponds to approximately 10g / m² inside the enclosure 4. 3 The dehumidified environment creates a less condensation-prone atmosphere around the modules.

[0045] Immediately after the meat processing line is shut down, the surface of the housing 4 and the conveying means 7 of the X-ray inspection device 1 are cleaned with high-temperature steam. In addition to the removal of any attached meat fat by the high-temperature steam, the area around the device becomes highly humid. The meat processing line remains stationary until it is restarted, but the housing 4 draws in humid outside air through tiny gaps in the cover and door due to the decrease in air pressure caused by the drop in internal temperature. In this way, humid air is drawn into the housing 4.

[0046] When the main power to the X-ray inspection device 1 is turned ON for restart, a warm-up operation begins.

[0047] During the inspection operation of the X-ray inspection device 1, the X-ray source 5 becomes hot, and the air conditioner 9 operates frequently, resulting in a certain level of dehumidification. Depending on the atmosphere in which the X-ray inspection device 1 is installed, the amount of heat generated increases when the X-ray source 5 irradiates X-rays at an intensity above a predetermined level. Therefore, it has been found that the humidity is generally kept below a threshold because it is constantly dehumidified by the cooling operation of the air conditioner 9. However, if there is humid air inside the housing 4, such as immediately after the warm-up operation is completed and the inspection has started, condensation may occur in localized low-temperature areas, i.e., in the locally cooled X-ray detection unit 6. In addition, a condensation alarm may be issued if, for example, the detected humidity exceeds a threshold during inspection operation.

[0048] In the example described above, after the main power supply of the X-ray inspection device 1 is turned ON and the warm-up operation is completed, humid air is present around the X-ray detection unit 6, and condensation is likely to occur near the Peltier element that locally cools the semiconductor chip of the line sensor unit that constitutes the X-ray detection unit 6.

[0049] Next, I will explain the function of the above-described configuration.

[0050] In the X-ray inspection apparatus 1 according to this embodiment, a cooling means is provided within the housing 4. The cooling means protects electrical components from heat by sending cold air to, for example, the X-ray source 5 and the X-ray detection unit 6, and cooling is performed by heat transfer through the circulation of the cold air within the housing 4, thereby promoting heat dissipation from the electrical components. In addition, the X-ray inspection apparatus 1 detects the X-rays 3 that are irradiated onto the object to be inspected 2 and transmitted through by the X-ray detection unit 6. A Peltier element is provided in contact with the X-ray detection unit 6 as a local cooling means, mainly protecting the semiconductor chip of the line sensor unit from heat by heat conduction. In other words, the X-ray detection unit 6 is a group of modules that operate in a cooled state. For this reason, the X-ray detection unit 6 is a group of modules equipped with electrical components that are susceptible to condensation, which are prone to condensation due to the cooling of the local cooling means, and whose failure is a concern due to the adhesion of condensed water droplets.

[0051] Conventionally, when the main power supply of the X-ray inspection device 1 was turned ON and the inspection could begin, if the module group equipped with a Peltier element was also activated, condensation would occur on the module group depending on the local temperature difference (relative humidity), and water droplets would adhere to the surface of the electrical components, causing semiconductor chip failure.

[0052] In the X-ray inspection apparatus 1 of this embodiment, the humidity near the module group, which is susceptible to condensation, inside the housing 4 is monitored by a humidity sensor 15. The first control unit 16 controls the supply of power to each electrical unit based on the value detected by the humidity sensor 15. If the humidity detected by the humidity sensor 15 is above a predetermined value, the X-ray detection unit 6, which has the module group that is susceptible to condensation, does not turn ON. This prevents the Peltier elements provided in the module group in the X-ray detection unit 6 from being driven in high humidity conditions, thus preventing failure of the line sensor unit due to, for example, water droplets adhering to the semiconductor chip of the line sensor unit. When the value detected by the humidity sensor 15 falls below a predetermined value, the first control unit 16 supplies power to the module group, i.e., the X-ray detection unit 6. Therefore, the X-ray inspection apparatus 1 can effectively suppress condensation in the module group, which is equipped with an integrated local cooling means.

[0053] Considering only the semiconductor chip of the line sensor unit that constitutes the X-ray detection unit 6, when the main power supply of the X-ray inspection device 1 is turned ON and the warm-up operation is completed, the power supply to the semiconductor chip and its peripheral circuits is turned OFF. First, the first control unit 16 monitors the detected value of the humidity sensor 15. If the value exceeds the threshold and the humidity is high, the dehumidification means (air conditioner 9) dehumidifies the inside of the housing 4. If the detected value of the humidity sensor 15 falls below the threshold, for example, when the initial relative humidity is 90%, the main power supply is turned ON, and after dehumidification, when the internal relative humidity falls below 70% to 60%, the first control unit 16 turns ON the power supply to the semiconductor chip and its peripheral circuits. In other words, the power supply to the module group, which is susceptible to condensation, is turned ON after the humidity has been reduced to a certain level. This solves the problem that the module group may condense, especially at the start of operation. After that, the operation of the device, i.e., inspection, begins.

[0054] As a result, the X-ray inspection device 1 can prevent condensation on electrical components due to localized cooling and suppress failures of electrical components.

[0055] In this X-ray inspection apparatus 1, the cooling means includes an air conditioner 9. Including the air conditioner 9 means that the cooling means also includes the Peltier element described above. The cooling means is an air conditioner 9 that circulates cold air inside the housing 4 to cool the space inside the housing 4, and is also a cooling unit such as a Peltier element that is integrated into a specific group of modules in order to locally cool the group of modules. The humidity sensor 15 is preferably located near the group of modules in the X-ray detection unit 6, in a position where it is cooled by the cooling unit such as the Peltier element.

[0056] The air conditioner 9 has a dehumidifying function. The air conditioner 9 has a refrigeration cycle that circulates a refrigerant by connecting a compressor, condenser, expansion valve, evaporator, etc., through piping to form a heat exchanger. The refrigerant, compressed by the compressor and becoming heated vapor, is sent to the condenser where it is cooled and becomes liquid. This liquid refrigerant passes through the expansion valve, evaporates in the evaporator, and cools the evaporator by absorbing heat of vaporization. By sending air from a fan to this evaporator, the heat-exchanged cold air is supplied into the housing 4.

[0057] The dehumidifying function of the air conditioner 9 utilizes condensation in the evaporator, which is at a low temperature. Specifically, the evaporator is cooled to its dew point temperature relative to the relative humidity of the air inside the enclosure 4, which is supplied by the blower fan. This cools the water vapor, which has condensed, and the water is then discharged outside the device for removal.

[0058] Dehumidification aims to remove moisture from the atmosphere, and like cooling, cool air is blown out from the evaporator. If pure dehumidification is desired and cooling is not required, the blown air is reheated. This allows for a significant reduction in relative humidity without changing the temperature inside the enclosure 4, creating an atmosphere less prone to condensation inside the enclosure 4. In addition, in the X-ray inspection apparatus 1, the X-ray source 5 needs to be heated, but not to a high temperature. The module group containing semiconductor chips needs to be heated, but also cooled, presenting conflicting requirements. Therefore, at the start of operation, a warm-up operation is performed to stabilize the operating temperature of each internal electrical unit, and the air conditioner 9 operates not only in dehumidification mode but also in cooling mode. By using the functions of the air conditioner 9, the X-ray inspection apparatus 1 can perform both cooling and dehumidification inside the enclosure 4.

[0059] Furthermore, by using an air conditioner 9 that circulates cool air within the housing 4 of the X-ray inspection device 1 in combination with cooling means such as a Peltier element that locally cools the contact surface, it is possible to achieve a good balance between cooling and dehumidification within the housing 4, and cooling of the module group which is susceptible to condensation.

[0060] In this X-ray inspection apparatus 1, when the temperature detected by the temperature sensor exceeds a predetermined value, the cooling function of the air conditioner 9 is activated. That is, for example, the X-ray source 5 is heated by the power supply, and then the cooling and dehumidifying functions of the air conditioner 9 are turned on. This makes it possible to maintain the temperature inside the housing 4 that has been stabilized by the warm-up operation, suppressing changes in the performance of electrical units caused by temperature changes, and thereby stabilizing the performance of the X-ray inspection apparatus. The X-ray source 5 has a tank, and the X-ray source is housed in this tank filled with cooling oil. The tank cooling section provided on the top surface of the tank has heat dissipation fins covered by a cover. At the start of operation, the X-ray inspection apparatus 1 requires a warm-up operation to bring the X-ray source to a predetermined temperature. However, to avoid it becoming too hot, i.e., a high temperature state, cooling by the air conditioner 9 is necessary. As a result, the warm-up operation can be performed, and dehumidification inside the housing 4 can also be performed.

[0061] Therefore, according to the X-ray inspection apparatus 1 of this embodiment, it is possible to cool the inside of the housing 4 while preventing condensation on electrical components and suppressing failure of electrical components. [Explanation of symbols]

[0062] 1...X-ray inspection equipment 2...Item under inspection 3...X-ray 4…Cabinet 5…X-ray source (non-condensing module group) 6…X-ray detection unit (module group) 9…Air conditioner (means of dehumidification, means of cooling) 15… Humidity sensor 16…First Control Unit (Control Unit) 20...Dehumidifier

Claims

1. In an X-ray inspection device (1) that inspects an object to be inspected (2) by detecting X-rays (3) that are irradiated onto the object to be inspected and transmitted through it, An X-ray detection unit (6) is located inside the housing (4) and detects the X-rays, An air conditioner (9) for cooling the inside of the enclosure, A first dehumidifying means and a second dehumidifying means for dehumidifying the inside of the housing, An X-ray inspection apparatus characterized by being equipped with the following features.

2. An X-ray inspection apparatus according to claim 1, An X-ray inspection apparatus characterized in that the first dehumidifying means is the dehumidifying function of the air conditioner.

3. An X-ray inspection apparatus according to claim 1 or claim 2, An X-ray inspection apparatus characterized in that the second dehumidifying means is a dehumidifier (20) dedicated to dehumidification.

4. An X-ray inspection apparatus according to claim 3, An X-ray inspection apparatus characterized in that the second dehumidifying means is located near the X-ray detection unit.

5. An X-ray inspection apparatus according to claim 3, An X-ray inspection apparatus characterized in that the second dehumidifying means is arranged on the air guide path of the X-ray detection unit.

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