JP5691540B2 - Cleaning device - Google Patents

Description

  The present invention relates to a cleaning apparatus for cleaning electronic parts, machine parts and the like in addition to medical instruments.

  Conventionally, a cleaning device disclosed in Patent Document 1 below is known. As described in [0033] and [0034], the cleaning device described in Patent Document 1 opens the exhaust valve (23b) while the exhaust device (30) is in operation, and the cleaning tank (20). The inside is depressurized and the cleaning liquid (24) is boiled. Thereafter, as described in [0037], the leak valve (26) is opened with the exhaust valve (23b) closed, and the outside air is introduced from the air guide pipe (25) by the pressure difference between the inside and outside of the cleaning tank (20). . In this way, as described in [0038], the introduced outside air becomes bubbles to come into contact with the object to be cleaned, the cleaning liquid is oscillated by the bubbles, or an impact at the time of pressure release is applied to the cleaning effect. Is going to get.

  However, in the cleaning device described in Patent Document 1, after the pressure in the cleaning tank is reduced and the cleaning liquid is boiled, “the exhaust valve 23b is closed and the leak valve 26 is opened”, and outside air is discharged to the liquid phase portion. Introduce. In this case, when the exhaust valve is closed, the gas phase portion is immediately filled with steam, and the boiling of the cleaning liquid stops. Therefore, the cleaning device described in Patent Document 1 does not introduce outside air into the liquid phase part during boiling of the cleaning liquid, and therefore cannot suddenly boil (violently boil) the cleaning liquid.

  On the other hand, as disclosed in the following Patent Document 2, the applicant first heated the cleaning liquid to a set temperature, and then reduced the pressure in the cleaning tank to boil the cleaning liquid. Has proposed a cleaning device that cleans an object to be cleaned by introducing outside air into the liquid phase portion while continuing to exhaust air and causing the cleaning liquid to bump.

  In this apparatus, the outside air is naturally sucked by the pressure difference from the atmospheric pressure while the cleaning liquid is boiling. In this case, the pressure of the bubbles introduced into the liquid becomes the pressure in the cleaning tank itself until the first bubbles reach the gas phase portion. Therefore, by introducing air bubbles into the liquid, the introduced bubbles expand explosively using the introduced gas as the core of boiling. Specifically, the bubbles introduced into the liquid expand in the washing tank under reduced pressure, and further rise when the liquid boiling vapor enters, and then rise in the liquid phase part. In this way, the liquid can be boiled, and the liquid can be greatly swung by the explosive jetting of the liquid and the subsequent dropping, thereby effectively cleaning the object to be cleaned.

Japanese Patent Laid-Open No. 10-10509 (paragraph numbers 0025-0041, FIG. 1) International Publication No. 2010/137212

  As a result of the diligent research on the cleaning apparatus using such bumping, the inventors of the present invention have found that the bumping due to the supply of air to the liquid phase portion is caused by the temperature of the liquid in the cleaning tank (both the pressure in the cleaning tank). It was found that it depends on. In other words, the higher the temperature of the liquid, the smaller the temperature difference between the upper and lower layers of the liquid in the cleaning tank, so even if air bubbles that are the core of boiling are introduced, there is no overheating area and bumping is less likely to occur. I understood.

  Specifically, FIG. 5 is a diagram showing the relationship between the saturation pressure and the saturation temperature of the liquid in the cleaning tank, but the same pressure difference ΔP (specifically, the upper and lower layers of the stored liquid in the cleaning tank) It can be seen that the temperature difference ΔT, ΔT ′ corresponding to the water head pressure becomes smaller as the pressure becomes higher (ΔT> ΔT ′). In order to cause the liquid to bump, a superheated region is required in the liquid. Therefore, a small temperature difference is disadvantageous for inducing bumping.

  Thus, it was found that the presence or absence of bumping phenomenon depends on the temperature of the cleaning liquid, and when the cleaning liquid is hot, bumping phenomenon is unlikely to occur even if the liquid phase is supplied to the liquid phase during boiling. In addition, when the cleaning liquid is high in temperature, if the boiling is carried out under reduced pressure, the temperature drops significantly, so that there is a disadvantage that only the cleaning liquid is cooled although the cleaning effect is low.

  The problem to be solved by the present invention is to provide a cleaning apparatus that predicts the presence or absence of bumping and executes an optimal cleaning operation.

The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is a cleaning tank for storing an aqueous solution and immersing an object to be cleaned, and heating the aqueous solution in the cleaning tank. A heating means, a decompression means connected to a gas phase part in the cleaning tank, sucking and discharging the gas in the cleaning tank to the outside, and depressurizing the cleaning tank, and a liquid phase part in the cleaning tank And a liquid-phase air supply means that opens the liquid-phase air supply valve in a state where the inside of the cleaning tank is decompressed, and after the pressure in the cleaning tank is reduced by the pressure-reducing means, the liquid-phase air supply valve is opened. The outside air is introduced into the aqueous solution in the cleaning tank from below the object to be cleaned due to the pressure difference between the inside and outside of the cleaning tank, and the pressure in the cleaning tank by the pressure reducing means is the pressure of the aqueous solution in the cleaning tank. When the temperature is lower than a predetermined temperature, the pressure of the gas phase in the cleaning tank is changed to the vapor of the aqueous solution in the cleaning tank. When the temperature of the aqueous solution in the cleaning tank is equal to or higher than a predetermined temperature, the pressure of the gas phase portion in the cleaning tank does not become lower than the vapor pressure of the aqueous solution in the cleaning tank. The cleaning apparatus is characterized in that the predetermined temperature is set in a range of 60 to 95 ° C. without stopping the aqueous solution by boiling down to a pressure.

  According to the first aspect of the present invention, when the aqueous solution in the washing tank is lower than the predetermined temperature, the aqueous solution is boiled under reduced pressure, and then the aqueous solution is bumped by supplying air to the liquid phase part. When the temperature of the aqueous solution is equal to or higher than the predetermined temperature, the pressure of the aqueous solution is stopped within a range that does not boil under reduced pressure, and cleaning by supplying air to the liquid phase part is performed to prevent an excessive temperature drop of the aqueous solution. The object to be cleaned can be cleaned.

According to invention of Claim 1 , if it is lower than the predetermined temperature set in the range of 60 to 95 ° C., an operation for causing boiling or bumping in the aqueous solution in the washing tank is performed, and if higher than the predetermined temperature, By performing an operation that does not cause boiling or bumping of the aqueous solution in the cleaning tank, it is possible to effectively clean the object to be cleaned while preventing an excessive temperature drop of the aqueous solution.

Further, the invention according to claim 2 is the heating of the aqueous solution up to the first set temperature by the heating means, and the pressure reducing means until the set condition is satisfied in a state in which the liquid phase air supply valve is closed. The pressure reduction in the washing tank and the introduction of the outside air into the aqueous solution by opening the liquid-phase air supply valve are sequentially repeated, and the setting condition is that the aqueous solution in the washing tank becomes the second set temperature, When the second set temperature is lower than the predetermined temperature, the aqueous solution is boiled by the pressure reduction in the cleaning tank by the pressure reducing means. When the second set temperature is equal to or higher than the predetermined temperature when the liquid phase supply valve is opened during the boiling to introduce the outside air into the aqueous solution, The reduced pressure inside does not boil the aqueous solution. A cleaning apparatus according to claim 1, characterized in that introducing the outside air into the aqueous solution by opening the liquid phase air supply valve state.

According to the second aspect of the present invention, when the heating of the aqueous solution, the pressure reduction in the washing tank, and the introduction of the outside air into the aqueous solution are repeated, the aqueous solution is boiled or bumped according to the temperature of the aqueous solution. By switching whether or not to generate, it is possible to effectively clean the object to be cleaned while preventing an excessive temperature drop of the aqueous solution.

  According to the present invention, it is possible to predict the presence or absence of bumping and execute an optimal cleaning operation.

It is the schematic which shows one Embodiment of the washing | cleaning apparatus of this invention, and shows a part in cross section. It is a figure which shows the driving | running state of the washing | cleaning apparatus of FIG. 1, and the graph has shown the relationship between the liquid temperature T in the washing tank, and the elapsed time t, (A) to (C) respond | corresponds with a graph. It is a time chart which shows. It is a figure which shows the relationship between the temperature and pressure in a washing tank, and elapsed time, and shows the case where a liquid is dared to boil even if 2nd preset temperature is more than predetermined temperature irrespective of this invention. It is a figure which shows the relationship between the temperature and pressure in a washing tank, and elapsed time, and when the 2nd preset temperature is more than predetermined temperature by this invention, the case where a liquid is not boiled under reduced pressure is shown. It is a figure which shows the relationship between the saturation pressure and saturation temperature of the liquid in a washing tank.

Hereinafter, an embodiment of a cleaning apparatus of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing an embodiment of the cleaning apparatus of the present invention, and a part thereof is shown in cross section. The cleaning apparatus 1 according to the present embodiment includes a cleaning tank 3 that stores liquid (cleaning liquid) and immerses an object to be cleaned 2, heating means 4 that heats the liquid in the cleaning tank 3, and the cleaning tank 3 Decompression means 5 that sucks and discharges the gas to the outside and decompresses the inside of the cleaning tank 3, liquid phase supply means 6 that introduces outside air into the liquid phase portion in the decompressed cleaning tank 3, and a decompressed cleaning tank 3 is provided with a gas-phase air supply means 7 for introducing outside air into the gas-phase portion in the apparatus 3. Furthermore, the cleaning apparatus 1 includes a pressure sensor 8 that detects the pressure of the gas phase portion in the cleaning tank 3, a temperature sensor 9 that detects the temperature of the liquid phase portion in the cleaning tank 3, and detection of these sensors 8 and 9. And control means (not shown) for controlling the means 4 to 7 based on signals and the like.

  The cleaning tank 3 is a hollow container that can withstand pressure reduction in the internal space. The cleaning tank 3 includes a main body 10 that opens upward and has a hollow portion, and a door 11 that opens and closes the opening of the main body 10. With the door 11 closed, the gap between the main body 10 and the door 11 is sealed with the packing 12. Thereby, the hollow part of the main body 10 is sealed, and a sealed space is formed in the cleaning tank 3.

  The object to be cleaned 2 is accommodated in the cleaning tank 3, and the liquid is stored up to a set liquid level (150 to 250 mm, for example, 200 mm in this embodiment) from the bottom surface in the cleaning tank 3 when the object to be cleaned 2 is immersed. Is done. The liquid stored in the cleaning tank 3 is not particularly limited as long as it is an aqueous solution, and is, for example, water (specifically pure water) or water containing a detergent. In this embodiment, it is water containing 0.5% detergent. The article to be cleaned 2 is an article to be cleaned, and is, for example, a medical instrument, an electronic component, or a mechanical component.

  The cleaning tank 3 is provided with a pressure sensor 8 that detects the pressure of the gas phase part in the cleaning tank 3 and a temperature sensor 9 that detects the temperature of the liquid phase part in the cleaning tank 3.

  The heating means 4 warms the liquid in the cleaning tank 3. Although the specific structure in particular is not ask | required, the heating means 4 is the electric heater 13 arrange | positioned in the bottom part in the washing tank 3 in this embodiment. In this case, the liquid in the cleaning tank 3 can be heated by energizing the electric heater 13 with the liquid stored in the cleaning tank 3.

  The decompression means 5 is connected to a gas phase portion in the cleaning tank 3 and sucks and discharges the gas in the cleaning tank 3 to the outside to decompress the inside of the cleaning tank 3. Specifically, the decompression unit 5 includes a vacuum generator 14, and the vacuum generator 14 is connected to a gas phase portion in the cleaning tank 3 through an exhaust passage 15. The specific structure of the vacuum generator 14 is not particularly limited. Typically, the vacuum generator 14 includes a water-sealed vacuum pump, and a heat exchanger that condenses the vapor in the exhaust passage 15 is provided upstream of the vacuum pump. Further, it may be provided. Further, the exhaust passage 15 may be provided with an air / water separator such as a demister in order to remove liquid droplets and solids contained in the gas from the cleaning tank 3 at the outlet of the cleaning tank 3. .

  The liquid phase air supply means 6 is connected to the liquid phase part in the cleaning tank 3, and external air is supplied to the liquid phase part in the cleaning tank 3 by the differential pressure between the pressure in the cleaning tank 3 and the atmospheric pressure outside the cleaning tank 3. Is introduced. Specifically, the liquid phase air supply means 6 introduces outside air into the liquid phase portion in the pressure-reduced cleaning tank 3 through the liquid phase air supply path 16. The liquid phase air supply path 16 is provided with a filter 17 and a liquid phase air supply valve 18 in order toward the cleaning tank 3. Therefore, when the liquid-phase air supply valve 18 is opened in a state where the pressure in the cleaning tank 3 is reduced, air through the filter 17 is introduced into the liquid phase portion in the cleaning tank 3 due to the pressure difference inside and outside the cleaning tank 3. can do.

  By the way, in this embodiment, the air from the liquid phase air supply path 16 is introduced into the liquid in the cleaning tank 3 via the liquid phase air supply nozzle 19 provided at the bottom in the cleaning tank 3. The liquid-phase air supply nozzle 19 is a pipe disposed laterally at the bottom of the cleaning tank 3. In this embodiment, this pipe is provided so as to meander the bottom of the cleaning tank 3. In addition, the pipe is held at the bottom in the cleaning tank 3 but horizontally from the bottom. Furthermore, nozzle holes 20 are formed in the pipe so as to open downward on the peripheral side wall of the pipe at set intervals along the extending direction. Thereby, if the liquid phase air supply valve 18 is opened in a state where the inside of the cleaning tank 3 is depressurized, air can be uniformly introduced into the liquid in the cleaning tank 3.

  The gas-phase air supply means 7 is connected to the gas-phase part in the cleaning tank 3, and the outside air is supplied to the gas-phase part in the cleaning tank 3 by the differential pressure between the pressure in the cleaning tank 3 and the atmospheric pressure outside the cleaning tank 3. Is introduced. Specifically, the gas phase air supply means 7 introduces outside air into the gas phase portion in the pressure-reduced cleaning tank 3 through the gas phase air supply path 21. A filter 22 and a gas phase air supply valve 23 are provided in the gas phase air supply path 21 in order toward the cleaning tank 3. Therefore, when the gas-phase gas supply valve 23 is opened in a state where the pressure in the cleaning tank 3 is reduced, air through the filter 22 is introduced into the gas-phase portion in the cleaning tank 3 due to the differential pressure inside and outside the cleaning tank 3. can do.

  The control means controls the means 4 to 7 based on the detection signals of the sensors 8 and 9. Specifically, in addition to the electric heater 13, the vacuum generator 14, the liquid phase air supply valve 18, and the gas phase air supply valve 23, the pressure sensor 8 and the temperature sensor 9 are connected to control means. Then, as described below, the control means cleans the article 2 to be cleaned in the cleaning tank 3 according to a predetermined procedure (program).

Hereinafter, an example of the operation method of the cleaning apparatus 1 of the present embodiment will be described.
FIG. 2 is a diagram showing the operating state of the cleaning apparatus 1 of the present embodiment, and the graph shows the relationship between the liquid temperature T in the cleaning tank 3 and the elapsed time t, and (A) to (C). These are time charts shown corresponding to the graphs. Here, (A) shows the presence or absence of the operation of the electric heater 13, (B) shows the presence or absence of the operation of the vacuum generator 14, and (C) shows opening and closing of the liquid phase supply valve 18.

  First, the object to be cleaned 2 is accommodated in the cleaning tank 3 and the liquid is stored, so that the object to be cleaned 2 is immersed in the stored liquid in the cleaning tank 3. Thereafter, a heating operation S1 for heating the liquid in the cleaning tank 3 to the first set temperature T1, a decompression operation S2 for reducing the pressure in the cleaning tank 3 until the set condition is satisfied, and an outside air in the liquid in the cleaning tank 3 Are sequentially executed. Thereafter, the heating operation S1, the pressure reducing operation S2, and the liquid phase air supply operation S3 are repeated until desired end conditions are satisfied as desired. Hereinafter, the first operations S1 to S3 will be described first, and then the second and subsequent operations S1 to S3 will be described.

  In the first heating operation S1, the liquid in the cleaning tank 3 is heated until the liquid in the cleaning tank 3 reaches the first set temperature T1. Specifically, the electric heater 13 may be operated with the liquid phase supply valve 18 and the gas phase supply valve 23 closed and the vacuum generator 14 stopped. During the heating operation S1, the temperature of the liquid in the cleaning tank 3 is monitored by the temperature sensor 9, and when the liquid in the cleaning tank 3 reaches the first set temperature T1, the electric heater 13 is stopped and the heating operation S1 is performed. Exit. In this heating operation S1, the inside of the cleaning tank 3 is depressurized by the vacuum generator 14 within a range where the liquid in the cleaning tank 3 is not boiled, and then the liquid-phase air supply valve 18 is opened to let outside air into the liquid-phase part. The operation | movement which introduce | transduces and stirs the liquid in the washing tank 3 may be performed suitably (FIG. 4).

  In the first decompression operation S2, the inside of the cleaning tank 3 is decompressed using the decompression means 5 until the set condition is satisfied. Specifically, the vacuum generator 14 may be operated with the liquid phase supply valve 18 and the gas phase supply valve 23 closed. The setting condition is that the liquid in the cleaning tank 3 reaches the second set temperature T2, the inside of the cleaning tank 3 reaches the second set pressure P2, or a set time that satisfies these conditions elapses. Note that the second set temperature T2 is the saturation temperature at the second set pressure P2, and conversely, the second set pressure P2 is the saturation pressure at the second set temperature T2, and the second set temperature T2 and the second set temperature T2. There is a predetermined relationship with the two set pressures P2.

  In the first liquid phase air supply operation S3, the operation of the pressure reducing means 5 is continued and the exhaust from the cleaning tank 3 is continued, and the difference between the inside and outside of the cleaning tank 3 is determined using the liquid phase air supplying means 6. The outside air is introduced into the liquid in the cleaning tank 3 from below the object to be cleaned 2 by pressure. Specifically, the liquid phase air supply valve 18 is opened while the operation of the vacuum generator 14 is continued, and the filter 17, the liquid phase air supply path 16, and the liquid phase air supply nozzle 19 are caused by the differential pressure from the atmospheric pressure. The outside air is introduced into the stored liquid via

  The air supplied to the liquid phase part by the liquid phase air supply means 6 eventually reaches the gas phase part and returns the pressure in the cleaning tank 3. In the liquid phase air supply operation S3, the inside of the cleaning tank 3 may be returned to atmospheric pressure. However, when the set of the heating operation S1, the pressure reduction operation S2, and the liquid phase air supply operation S3 is repeated, If the pressure is restored to atmospheric pressure, the decompression time is wasted in the next decompression operation. Therefore, it is preferable to close the liquid-phase air supply valve 18 so as to stop at the predetermined pressure below atmospheric pressure.

  When the second set temperature T2 is lower than the predetermined temperature, in the pressure reducing operation S2, the pressure of the gas phase portion in the cleaning tank 3 is lowered below the vapor pressure of the liquid in the cleaning tank 3, and the liquid in the cleaning tank 3 is Boiling. Then, in the liquid phase air supply operation S3, the liquid phase air supply valve 18 is opened during the boiling of the liquid, the outside air is introduced into the liquid, and the liquid suddenly boils.

  The reason why the bumping phenomenon occurs is as follows. That is, first, the pressure of the bubbles introduced into the liquid becomes the pressure itself in the cleaning tank 3 until the first bubbles reach the gas phase portion. Therefore, by introducing air bubbles into the liquid, the introduced bubbles expand explosively using the introduced gas as the core of boiling. Specifically, the bubbles introduced into the liquid expand in the washing tank 3 under reduced pressure, and further rise when the liquid boiling vapor enters, and rise in the liquid phase part. In this way, the liquid to be cleaned can be effectively washed by causing the liquid to boil and oscillating the liquid largely by the explosive jetting of the liquid and the subsequent dropping.

  On the other hand, when the second set temperature T2 is equal to or higher than the predetermined temperature, in the pressure reducing operation S2, the pressure of the gas phase portion in the cleaning tank 3 is stopped to be reduced to a pressure not lower than the vapor pressure of the liquid in the cleaning tank 3. The liquid in the cleaning tank 3 does not boil. Then, in the liquid phase supply operation S3, the liquid phase supply valve 18 is opened to introduce the outside air into the liquid that has not boiled. In this way, the object to be cleaned 2 can be cleaned by the rise of the outside air introduced into the liquid and the resulting rocking of the liquid.

  The predetermined temperature takes into consideration the rate of decrease in liquid temperature when boiling under reduced pressure (cooling faster as the temperature rises under reduced pressure) and whether or not bumping can occur (the higher the temperature, the less likely bumping occurs). For example, it is set in the range of 60 to 95 ° C, more preferably in the range of 60 to 70 ° C. In this embodiment, it is set to 70 ° C., for example. As described with reference to FIG. 5 in the section “Problems to be Solved by the Invention”, the higher the temperature, the smaller the temperature difference between the upper and lower layers of the liquid in the cleaning tank 3. Even if bubbles are introduced, an overheated region is not formed and bumping is less likely to occur. On the other hand, the higher the temperature, the more the liquid is cooled by boiling under reduced pressure. Therefore, the predetermined temperature is determined in consideration of these.

  The first set temperature T1 may be set based on the second set temperature T2 (or the saturation temperature at the second set pressure P2). For example, the first set temperature T1 is set to a temperature that is higher than the second set temperature T2 by a predetermined temperature (for example, 0.5 to 2 ° C.).

  As described above, the heating operation S1, the pressure reducing operation S2, and the liquid phase air supply operation S3 are performed. Thereafter, these operations are sequentially repeated as desired. In that case, first, the heating operation S1 is performed again. In the heating operation S1, the electric heater 13 is energized to heat the liquid in the cleaning tank 3 to the first set temperature T1. In this heating operation S1, the vacuum generator 14 continues to operate, but may be stopped depending on circumstances. When the operation of the vacuum generator 14 is continued in the heating operation S1, the liquid in the cleaning tank 3 will boil if the liquid-phase air supply valve 18 is closed. The operation of opening the valve 18 is repeated. When the liquid in the cleaning tank 3 reaches the first set temperature T1, the electric heater 13 is stopped and the pressure reduction operation S2 is performed thereafter.

  The subsequent decompression operation S2 is the same as the first decompression operation S2 described above, and the liquid phase supply valve 18 is maintained closed, for example, so that the liquid in the cleaning tank 3 reaches the second set temperature T2. The inside of the cleaning tank 3 is depressurized by the vacuum generator 14 until the set condition of When this setting condition is satisfied, the liquid phase air supply operation S3 is performed.

  The liquid phase air supply operation S3 is the same as the first liquid phase air supply operation S3 described above, and the liquid phase air supply valve 18 is opened to introduce outside air into the stored liquid in the cleaning tank 3. Also in this case, when the second set temperature T2 is lower than the predetermined temperature, the liquid is boiled in the pressure reducing operation S2, and the liquid is bumped by introducing outside air into the boiling liquid in the liquid phase air supply operation S3. However, when the second set temperature T2 is equal to or higher than the predetermined temperature, the liquid is not boiled even in the pressure reducing operation S2, and outside air is introduced into the liquid in the liquid phase air supply operation S3, and the liquid does not bump.

  In this way, the heating operation S1, the pressure reducing operation S2, and the liquid phase air supply operation S3 are repeated until a predetermined end condition is satisfied. As the end condition, the end point of the first heating operation S1 is set. Elapsed time from the above and the number of executions of the liquid phase air supply operation S3 can be employed.

  If the end condition is satisfied, the liquid-phase supply valve 18 is closed, the electric heater 13 and the vacuum generator 14 are stopped, the gas-phase supply valve 23 is opened, and the inside of the cleaning tank 3 is returned to atmospheric pressure. Just press. Thereafter, if desired, the liquid in the cleaning tank 3 may be exchanged to clean the object to be cleaned 2 again, or the object to be cleaned 2 may be dried. In the present embodiment, the washing includes rinsing.

  By the way, in each pressure reduction operation | movement S2 mentioned above, although the heating means 4 was stopped, you may continue an action | operation depending on the case.

  3 and 4 are diagrams showing the relationship between the temperature T and pressure P in the cleaning tank 3 and the elapsed time t. Among these, FIG. 3 shows an example in which the liquid phase air supply operation S3 is executed after the pressure reducing operation S2 is executed until the stored liquid is boiled even when the second set temperature T2 is equal to or higher than the predetermined temperature. On the other hand, FIG. 4 shows an example in which when the second set temperature T2 is equal to or higher than the predetermined temperature, the liquid phase air supply operation S3 is executed after the pressure reducing operation S2 is executed in a range in which the stored liquid is not boiled according to the present invention. Show.

  As shown in FIG. 3, although the liquid is at a high temperature (93 ° C. in the illustrated example), if the liquid is boiled under reduced pressure in the pressure reducing operation S2, the cooling of the liquid becomes large. Therefore, the time required for one depressurizing pressure pulse (liquid phase air supply operation S3 after the pressure reducing operation S2) is also increased.

  On the other hand, as shown in FIG. 4, when the liquid is at a high temperature (93 ° C. in the illustrated example) and the liquid phase part is supplied without boiling under reduced pressure, cooling of the liquid is suppressed, Many decompression pulses can be executed in the same time. In FIG. 3, the temperature change was 5 ° C., but in FIG. 4, the temperature change was within 1 ° C., and the local temperature unevenness was also within 1 ° C.

  The cleaning apparatus 1 of the present invention is not limited to the above-described embodiment, and can be changed as appropriate. In particular, when the temperature of the liquid in the cleaning tank 3 is lower than a predetermined temperature, the liquid is boiled by depressurization in the cleaning tank 3, and the liquid is bumped by air supply to the liquid phase part thereafter, while the cleaning tank 3 If the temperature of the liquid in the tank is equal to or higher than the predetermined temperature, other configurations and controls are appropriately performed as long as the liquid is not boiled or bumped even by depressurization in the cleaning tank 3 or supply of air to the liquid phase part. It can be changed.

DESCRIPTION OF SYMBOLS 1 Cleaning apparatus 2 Object to be cleaned 3 Cleaning tank 4 Heating means 5 Depressurizing means 6 Liquid phase air supply means 7 Gas phase air supply means 8 Pressure sensor 9 Temperature sensor 13 Electric heater 14 Vacuum generator 18 Liquid phase air supply valve T1 No. 1 One set temperature T2 Second set temperature

Claims (2)

A cleaning tank for storing an aqueous solution and immersing an object to be cleaned;
A heating means for heating the aqueous solution in the washing tank;
A pressure reducing means connected to a gas phase portion in the cleaning tank, sucking and discharging the gas in the cleaning tank to the outside, and depressurizing the cleaning tank;
A liquid phase supply means connected to the liquid phase portion in the cleaning tank and opening the liquid phase supply valve in a state where the pressure in the cleaning tank is reduced,
After the pressure in the cleaning tank is reduced by the pressure reducing means, the liquid-phase air supply valve is opened, and the outside air is introduced into the aqueous solution in the cleaning tank from below the object to be cleaned by the differential pressure inside and outside the cleaning tank. And
When the temperature of the aqueous solution in the cleaning tank is lower than a predetermined temperature, the pressure in the cleaning tank is reduced by the pressure reducing means so that the pressure of the gas phase portion in the cleaning tank is equal to or lower than the vapor pressure of the aqueous solution in the cleaning tank. The aqueous solution is boiled by lowering the pressure until the temperature of the aqueous solution in the cleaning tank is equal to or higher than a predetermined temperature, but the pressure of the gas phase in the cleaning tank is not lower than the vapor pressure of the aqueous solution in the cleaning tank. Do not boil the aqueous solution by stopping the vacuum until
The said predetermined temperature is set in the range of 60-95 degreeC, The washing | cleaning apparatus characterized by the above-mentioned . The heating of the aqueous solution up to the first set temperature by the heating means, the pressure reduction in the cleaning tank by the pressure reduction means until the set condition is satisfied with the liquid phase air supply valve closed, and the liquid phase supply Repeat the introduction of outside air into the aqueous solution by opening the air valve,
The set condition is that the aqueous solution in the cleaning tank reaches a second set temperature or the inside of the cleaning tank reaches a pressure at which the second set temperature is a saturation temperature.
When the second set temperature is lower than the predetermined temperature, the aqueous solution is boiled by the pressure reduction in the washing tank by the pressure reducing means, and the liquid phase supply valve is opened during the boiling to introduce the outside air into the aqueous solution. To bump the aqueous solution,
When the second preset temperature is equal to or higher than the predetermined temperature, the aqueous solution does not boil due to the pressure reduction in the washing tank by the pressure reducing means, and the liquid phase air supply valve is opened in this state to introduce outside air into the aqueous solution. The cleaning apparatus according to claim 1 , wherein:

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