JP5370921B2 - Cleaning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve at the same time such problems as: how to reduce the space required, how to reduce the amount of a cleaning liquid consumed, how to prevent generation of cavitation, and how to reduce clogging with fine particle foreign matter. <P>SOLUTION: In a cleaning apparatus including a cleaning vessel 3, a pressure reducing means 6 containing a heat exchanger 4 condensing gas in the cleaning vessel 3 and a vacuum pump 5, a pressure returning means 7 in the cleaning vessel 3, and a control means 14 for boiling the cleaning liquid in the cleaning vessel 3 by alternating pressure reduction and pressure return, the heat exchanger 4 is constituted by a plate-type heat exchanger for cooling gas with cooling water, and a gas-liquid separator 9 is installed upstream of the heat exchanger 4 to separate the cleaning liquid, fine liquid drops of the cleaning liquid and fine foreign matter contained in gas from the gas by a demister, and to return the separated liquid to the cleaning vessel 3. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

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

  Conventionally, as disclosed in the following Patent Document 1, a cleaning liquid is stored, a cleaning tank in which an object to be cleaned is immersed in the cleaning liquid, a heat exchanger that condenses the vapor contained in the gas in the cleaning tank, and this heat Including a vacuum pump provided downstream of the exchanger, vacuuming means for sucking and discharging the gas in the cleaning tank to the outside and depressurizing the cleaning tank, and introducing outside air into the vacuumed cleaning tank, There is known a cleaning device (hereinafter referred to as a reduced-pressure boiling cleaning device) that includes a pressure-recovery means for recovering the pressure of the liquid and boiles the cleaning liquid in the cleaning tank by repeating the pressure reduction and the pressure recovery.

Japanese Examined Patent Publication No. 63-32459 JP-A-7-136604

  The inventors of this application have found the following first to third problems in the cleaning device of Patent Document 1 in the process of developing a cleaning device similar to Patent Document 1. That is, the first problem is that a shell-and-tube heat exchanger is used as a heat exchanger for vapor condensation, so that the heat exchanger occupies a large volume, resulting in a large equipment and a large installation space. This is a problem of space saving. The first problem is an important problem to be solved for this type of cleaning apparatus installed in a hospital or the like. The second problem is a problem of large consumption of the cleaning liquid in which the cleaning liquid is discharged out of the cleaning tank due to boiling of the cleaning liquid and the cleaning liquid is significantly reduced. The cleaning liquid may flow out as fine droplets, or the water level in the cleaning tank may rise and the cleaning liquid may flow out. A third problem is a problem of cavitation that causes cavitation when a cleaning liquid having a temperature equal to or higher than the saturation temperature is sucked into the vacuum pump, and possibly damages the vacuum pump. The third problem is a new problem found by the inventors of this application in a vacuum boiling cleaning apparatus using a vacuum pump.

  In order to solve the first problem, an experiment was conducted in which the heat exchanger was a known plate heat exchanger, and it was found that there was a fourth problem. The fourth problem is that fine particles such as blood foreign matters (hereinafter referred to as fine foreign matters) contained in the cleaning liquid that flows out as liquid, and fine foreign matters contained in the fine droplets generated when the cleaning liquid is boiled (cleaning liquid and fine droplets). Is a problem of clogging of fine foreign matter that includes a fine gap (a gap can be referred to as a fluid flow gap) of the plate heat exchanger. When the fine foreign matter is clogged, the heat transfer efficiency of the heat exchanger is lowered, and as a result, the pressure reduction capability of the pressure reduction means is reduced and it takes time to reduce the pressure, that is, the time for vacuum cleaning is increased and the power consumption is increased. In addition, there is a problem that it is difficult to perform the regeneration work to eliminate the clogging of the heat exchanger. The fourth problem is a problem specific to the vacuum boiling washing apparatus in which the heat exchanger for condensation is a plate heat exchanger, and is a new problem found by the inventors of this application.

In order to solve the second problem, it is conceivable to provide a gas-liquid separator on the downstream side of the washing tank as in Patent Document 2, but a simple gas-liquid separator cannot solve the problem. In addition, since the gas-liquid separator of patent document 2 is a structure provided with a pressure reduction tank in the downstream, it does not intend the solution of a 3rd subject.

  The present invention simultaneously solves the first to fourth problems, that is, the problem of space saving, the problem of large consumption of cleaning liquid, the problem of cavitation generation, and the problem of clogging of fine particles in the vacuum boiling cleaning apparatus. It is.

The present invention has been made to solve the above problems, and the invention according to claim 1 is directed to a cleaning tank in which a cleaning liquid is stored and an object to be cleaned is immersed in the cleaning liquid, and a gas in the cleaning tank. And a vacuum pump provided downstream of the heat exchanger, decompressing means for sucking and discharging the gas to the outside and decompressing the inside of the washing tank, and outside air into the decompressed washing tank And a control means for boiling the cleaning liquid in the cleaning tank by controlling the pressure reducing means and the pressure recovery means to repeat the pressure reduction and the pressure recovery. The heat exchanger is configured by a plate heat exchanger that cools the gas with cooling water, and a cleaning liquid is contained in the gas by a demister on the upstream side of the heat exchanger. Microdroplets and microparticles Is separated from the gas, e Bei the gas-liquid separator to return the separated liquid to the cleaning tank, the gas-liquid separator, a container made to the heat exchanger separately from the inlet to the vessel A demister disposed so as to be divided into a side space and an outlet side space, and the container has a gas inlet for introducing gas from the cleaning tank into the inlet side space, and a cleaning liquid and a cleaning liquid by the demister. A gas outlet for discharging the gas after separating the droplets and fine foreign matters toward the heat exchanger, and a liquid outlet for returning the liquid separated by the demister to the cleaning tank, and regenerating or exchanging the demister. A liquid temperature sensor configured to detect the liquid temperature in the cleaning tank, and the control means is configured such that when the change gradient of the temperature detected by the liquid temperature sensor at the time of the pressure reduction is equal to or lower than a set value, Replay or exchange It is characterized by notifying the time.

According to the second aspect of the present invention, in the first aspect, the air supply path of the return pressure unit is connected to the outlet side space, and the air supply path, the outlet side space, the demister, and the gas inlet are connected. It is characterized in that the pressure inside the washing tank is restored by passing sequentially.

  According to the present invention, the first to fourth problems in the vacuum boiling cleaning apparatus, that is, the problem of space saving, the problem of large consumption of cleaning liquid, the problem of cavitation generation, and the problem of clogging of fine foreign matters are simultaneously solved. Can do.

It is the schematic which shows Example 1 of the washing | cleaning apparatus of this invention. It is a figure which shows the principal part of the control procedure of Example 1 of the washing | cleaning apparatus of this invention. It is the schematic which shows Example 2 of the washing | cleaning apparatus of this invention. It is a figure which shows the principal part of the control procedure of Example 2 of the washing | cleaning apparatus of this invention. It is the schematic which shows Example 3 of the washing | cleaning apparatus of this invention. It is the schematic which shows Example 4 of the washing | cleaning apparatus of this invention.

  Next, an embodiment of the cleaning apparatus of the present invention will be described. The embodiment of the present invention is not limited to cleaning of an object to be cleaned, but is preferably implemented in an apparatus that performs rinsing and disinfection.

  This embodiment will be specifically described. This embodiment includes a cleaning tank in which a cleaning liquid is stored and an object to be cleaned is immersed in the cleaning liquid, a decompression unit that sucks and discharges the gas in the cleaning tank to the outside, and depressurizes the cleaning tank. A return pressure means for introducing outside air into the cleaning tank and returning the pressure in the cleaning tank; and controlling the pressure reducing means and the return pressure means to repeat the pressure reduction and the return pressure. And a control means for boiling the cleaning liquid therein. The said pressure reduction means is comprised including the heat pump which condenses the said gas, and the vacuum pump provided downstream of the said heat exchanger.

  The heat exchanger is composed of a plate heat exchanger that cools the gas with cooling water. Then, on the upstream side of the heat exchanger, the cleaning liquid flowing out in a liquid state by a demister (also referred to as a demister blanket), the fine droplets and fine foreign substances of the cleaning liquid contained in the gas are separated from the gas and separated. The gas-liquid separator which returns a liquid to the said washing tank is provided. The plate heat exchanger is a known heat exchanger having a structure in which a large number of plates are stacked with minute gaps and the gas and cooling water are alternately circulated in the minute gaps.

  In Embodiment 1 of the present invention, since the heat exchanger is a plate heat exchanger, the occupied volume in the cleaning device is reduced as compared with a shell-and-tube heat exchanger having the same heat exchange capacity. The space can be saved by downsizing the cleaning device. In addition, compared to a shell-and-tube heat exchanger having the same outer dimensions, the heat transfer surface is wide and the cooling capacity is high, so that a predetermined cooling capacity can be exhibited with a small amount of cooling water. As a result, the amount of cooling water can be greatly reduced.

In addition, the cleaning liquid in the cleaning tank is boiled by repeating the decompression by the operation of the decompression means and the return pressure by the operation of the decompression means. When the cleaning liquid is boiled, fine droplets of the cleaning liquid and fine foreign matters such as blood foreign matters are contained in a gas (mostly steam) and flow out from the cleaning tank toward the plate heat exchanger. There are cases where the fine foreign matters are included in the cleaning liquid flowing out as the water level of the cleaning tank rises, are included in the fine droplets, or are released alone.

  The cleaning liquid that has flowed out, the fine droplets of the cleaning liquid, and the fine foreign matters are captured by the demister, and the cleaning liquid is separated from the gas. Since the separated cleaning liquid is returned to the cleaning tank and used for cleaning, the amount of cleaning liquid used is reduced.

  Further, since the washing liquid having a temperature equal to or higher than the saturation temperature is prevented from flowing out to the downstream side of the gas-liquid separator, cavitation caused when the washing liquid is sucked into the vacuum pump is prevented, and damage to the vacuum pump is prevented. .

  In addition, since the outflow of the cleaning liquid to the downstream side of the gas-liquid separator is prevented, the clogging of the minute gap of the plate heat exchanger by the cleaning liquid is prevented, and the heat transfer surface of the plate heat exchanger by the cleaning liquid is prevented. Reduction is prevented. The capture efficiency of the fine droplets by the demister is preferably 90% to 99%. As a result of preventing the reduction of the heat transfer surface, the vacuum pump can be depressurized to a predetermined pressure in the cleaning tank in a short time, and the cleaning time can be shortened. Moreover, as a result of being able to perform pressure reduction to a predetermined pressure in a short time, the amount of cooling water in the heat exchanger can be reduced.

  Further, the discharged foreign particles are removed by the demister, and the plate heat exchanger is prevented from being clogged by the fine particles. The diameter of the fine foreign matter to be removed by the demister is set smaller than the minute gap of the plate heat exchanger. Preferably, when the fine gap is set to 2 to 3 mm due to pressure loss, the diameter of the fine foreign matter to be removed by the demister is set to 1 mm or more. The preferable trapping efficiency of the fine foreign particles is 90 to 99%.

  In this way, fine foreign matters that cause clogging of the plate heat exchanger are captured by the demister, so that a decrease in heat transfer efficiency of the plate heat exchanger can be prevented. As a result, it is possible to solve the problem that the decompression time by the decompression means becomes long and the power consumption increases.

  In this embodiment, preferably, a pre-filter that captures fine foreign particles having a diameter larger than the fine foreign particles captured by the demister is provided on the upstream side of the demister. The prefilter is detachable and can be regenerated by removing clogged fine particles by washing or the like. If the diameter of the fine foreign material captured by the demister is 1 mm or more, the diameter of the foreign material captured by the prefilter is 5 mm or more.

  Here, the component which comprises the washing | cleaning apparatus of embodiment of this invention is demonstrated. The cleaning tank is capable of taking in and out the object to be cleaned, storing a predetermined amount of cleaning liquid, heating the stored cleaning liquid to a predetermined temperature by heating means, and reducing the internal pressure to a predetermined pressure and then reducing the return pressure Any structure that can withstand repeated pressure is acceptable, and the structure is not limited to a specific one.

  The decompression means includes the heat exchanger and the vacuum pump, and can include a steam ejector on the upstream side of the heat exchanger.

  The heat exchanger may be a plate type heat exchange in which a large number of plates are stacked with minute gaps, and the gas and cooling water are alternately circulated in the minute gaps. When the upper limit of the pressure loss is 1 kPa, it is set to 2 to 3 mm.

The vacuum pump is preferably a water-sealed vacuum pump. However, the present invention is not limited to this, and one of the problems of the present invention is to prevent cavitation caused by inhalation of a droplet having a saturation temperature or higher. Therefore, any vacuum pump that may cause this cavitation may be used.

  The gas-liquid separator has a function of performing gas-liquid separation for separating the cleaning liquid and the cleaning liquid microdroplets from the inflowing gas, a function of returning the separated cleaning liquid to the cleaning tank, and a microscopic function of the plate heat exchanger. It has a function of first capturing fine foreign matters that may be clogged in the gap and a function that can more easily eliminate clogging of fine foreign matters than the plate heat exchanger.

  In order to satisfy these functions, the gas-liquid separator is preferably disposed so as to partition the container into an inlet side space and an outlet side space, and a container configured separately from the heat exchanger. A demister, and the container exchanges the gas after introducing the gas from the cleaning tank into the inlet side space, and the gas after the cleaning liquid, the fine droplets of the cleaning liquid and the fine foreign particles are separated by the demister. A gas outlet for flowing out toward the vessel, and a liquid outlet for returning the liquid separated by the demister to the washing tank.

  In the configuration of the gas-liquid separator, the demister is preferably configured to perform most of the function of separating the cleaning liquid and the cleaning liquid microdroplets. However, the introduction direction of the gas introduced from the gas inlet is a horizontal circumferential direction with respect to the inner peripheral wall of the container, and the cleaning liquid and the fine droplets of the cleaning liquid are separated by centrifugal separation. It can be configured such that most of the function of separating droplets is performed by the centrifugal separation function and the rest is performed by the demister.

  The container is composed of a main body and a lid capable of opening and closing the main body, and the demister is detachably attached to the main body, thereby facilitating the regeneration or replacement of the demister. The regeneration of the demister includes not only cleaning with a liquid but also a method of blowing off fine foreign particles with gas. If the plate-type heat exchanger is clogged with fine foreign matter, it is necessary to wash and return dozens of plates one by one. On the other hand, by providing the demister detachably in a container separate from the heat exchanger, it is easy to remove the fine foreign matter captured by the demister. As compared with the case where the particles are trapped, the clogging of fine foreign matters can be easily eliminated.

  The function of returning the separated cleaning liquid to the cleaning tank is preferably realized by connecting the cleaning tank and the liquid outlet through a communication pipe not provided with a forced reflux means. The forced reflux means is a pump, but the apparatus configuration can be simplified by not providing the forced reflux means.

  The present invention is not limited to the embodiment of the invention described above, and instead of directly connecting the air supply path of the decompression means to the cleaning tank, it is connected to the outlet side space of the container, The inside of the washing tank can be re-pressured through the air supply path, the outlet side space, the demister, and the gas inlet sequentially.

  In addition, an informing means for informing the regeneration or replacement time of the demister can be provided. The informing means preferably includes a liquid temperature sensor for detecting the liquid temperature in the cleaning tank, and the control means has a change gradient of the detected temperature of the liquid temperature sensor at the time of the depressurization being a set value or less. It is configured to notify the regeneration or replacement time of the demister. When such a configuration is adopted, when the pressure in the cleaning tank is reduced, a liquid temperature sensor used for controlling the temperature of the cleaning liquid can be used as it is for the notification, and the configuration of the apparatus is simplified. Can be The notification means includes display by a display, notification by sound, and the like.

  However, the notifying means is configured to detect a differential pressure before and after the gas flow of the demister and to notify the regeneration or replacement timing of the demister when the detected differential pressure exceeds a set value. Can do.

  Embodiment 1 of the present invention will be described below 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 FIG. 2 is a flowchart showing the main part of the control procedure of the first embodiment.

  The cleaning apparatus 1 according to the first embodiment is provided with a cleaning tank 3 in which cleaning liquid is stored and an object to be cleaned 2 is immersed in the cleaning liquid, a heat exchanger 4 that condenses the gas, and a downstream of the heat exchanger 4. A vacuum pump 5 is included to suck and discharge the gas in the cleaning tank 3 to the outside to reduce the pressure in the cleaning tank 3, and to introduce the outside air into the pressure-reduced cleaning tank 3. Pressure recovery means 7 for returning pressure and upstream of the heat exchanger 4, a demister 8 separates the cleaning liquid, the cleaning liquid micro-droplets and the foreign particles from the gas from the gas, and the separated liquid is cleaned. A gas-liquid separator 9 that returns to 3 is provided as a main part.

  The heating means 10 for heating the cleaning liquid in the cleaning tank 3, the drain means 11 for discharging the cleaning liquid in the cleaning tank 3, the pressure sensor 12 for detecting the pressure in the cleaning tank 3, and the cleaning liquid in the cleaning tank 3 And a control means 14 for controlling the means 6, 7, 10, 11 based on detection signals of the sensors 12, 13 and the like.

  The cleaning device 1 can perform any one or more of cleaning, rinsing, and disinfection of the object to be cleaned 2. In the first embodiment, after the object to be cleaned 2 is cleaned and rinsed, the object to be cleaned 2 can be dried in one cleaning tank 3.

  The cleaning liquid is not particularly limited as long as it can be boiled by the pressure reduction in the cleaning tank 3 by the pressure reducing means 6, but is water, for example. In Example 1, the cleaning liquid is water containing about 0.5% of a cleaning agent. However, the cleaning liquid may be water that does not contain detergent as well as water that contains detergent. The cleaning liquid may be other liquid that can be used for cleaning, such as soft water, pure water, and a solvent.

  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 a hollow container that can withstand the decompression of the internal space. The cleaning tank 3 of the first embodiment includes a first container body (hereinafter simply referred to as a first body) 15 that opens upward and has a hollow portion, and a detachable that opens and closes the opening of the first body 15. A first lid 16. In the state where the first lid 16 is attached to the first body 15, the gap between the first body 15 and the first lid 16 is sealed with the first packing 17. Thereby, the hollow part of the 1st main body 12 is sealed, and the sealed space is formed in the washing tank 3.

  A water supply means 18 for supplying a cleaning liquid into the cleaning tank 3 is connected to the cleaning tank 3. The water supply means 18 of the first embodiment supplies the water in the raw water tank 19 to the cleaning tank 3 through the water supply channel 20. A water supply pump 21 and a first water supply valve 22 are provided in the water supply path 20 in order from the raw water tank 19 side. When the first water supply valve 22 is opened while the water supply pump 21 is operated, the water in the raw water tank 19 is supplied to the cleaning tank 3 through the water supply path 20. The water supplied to the cleaning tank 3 can be mixed with the cleaning agent from the chemical liquid tank 23 by the chemical injection pump 24 in the middle of the water supply channel 20. The opening / closing of the first water supply valve 22 is linked to the presence / absence of the operation of the water supply pump 21 and the chemical injection pump 24. However, the addition of the cleaning agent can be omitted as appropriate, and in this case, the installation of the chemical injection pump 24 and the chemical liquid tank 23 can be omitted.

  The cleaning tank 3 is connected to a decompression means 6 that sucks and discharges the gas in the cleaning tank 3 to the outside and decompresses the cleaning tank 3. The decompression means 6 according to the first embodiment sucks and discharges the gas in the cleaning tank 3 through the exhaust passage 25. In the exhaust passage 25, a heat exchanger 4, a check valve 26, and a water seal vacuum pump 6, which are constituent elements of the decompression means 6, are provided in this order from the gas-liquid separator 9 and the washing tank 3 side.

  The heat exchanger 4 is a plate heat exchanger that cools and condenses the steam in the exhaust passage 25. The plate heat exchanger 4 is formed by stacking a large number of plates with minute gaps, and alternately forming gas flow paths 27 and cooling water flow paths 28 in the minute gaps (the gas flow paths 27 and the cooling water flow paths 28 and 28 1 is a well-known heat exchanger having a structure in which only one is shown in FIG.

  Then, water is supplied to the cooling water passage 28 via the second water supply valve 29 and discharged. In the heat exchanger 4, by condensing the vapor in the exhaust passage 25 in advance, it is possible to reduce the subsequent load on the vacuum pump 6 and effectively reduce the pressure in the cleaning tank 3.

  As is well known, the water-sealed vacuum pump 6 is supplied with water called sealed water. Therefore, water is supplied to the vacuum pump 6 through the third water supply valve 30 and discharged. When operating the vacuum pump 6, the third water supply valve 30 is opened in conjunction with the vacuum pump 6.

  The gas-liquid separator 9 is provided on the upstream side of the heat exchanger 4 in the exhaust passage 25 and on the downstream side of the cleaning tank 3. The gas-liquid separator 9 includes a container 31 configured separately from the heat exchanger 4, and a demister 8 disposed so as to partition the inside of the container 31 into an inlet side space 32 and an outlet side space 33. It is configured.

  The container 31 includes a gas inlet 34 that introduces the gas from the cleaning tank 3 into the inlet side space 32, and a gas that causes the gas after the cleaning liquid and the fine droplets of the cleaning liquid are separated by the demister 8 to flow toward the heat exchanger 4. An outlet 35 and a liquid outlet 36 for refluxing the liquid separated by the demister 8 to the cleaning tank 3 are provided. The demister 8 has a function of capturing fine foreign matters of 1 mm or more so that the fine foreign matters are not clogged in the minute gaps of the heat exchanger 4. A pre-filter 37 for removing foreign matters having a diameter of 5 mm or more is provided at the inlet of the exhaust passage 25 in the cleaning tank 3.

  The container 31 has a second container body (hereinafter simply referred to as a second body) 38 that opens upward and has a hollow portion, and a detachable second lid 38 that opens and closes the opening of the second body 38. With. In the state where the second lid 39 is attached to the second body 38, the gap between the second body 38 and the second lid 39 is sealed with the second packing 40. Thereby, the hollow part of the 2nd main body 38 is sealed, and the sealed space is formed in the gas-liquid separator 9. Such a configuration facilitates cleaning or replacement of the demister 8.

  The bottom of the cleaning tank 3 and the liquid outlet 36 of the container 31 form a communication pipe 41 that does not include a pump. Thereby, the cleaning liquid separated in the gas-liquid separator 9 is returned to the cleaning tank 3. The liquid level of the gas-liquid separator 9 and the liquid level of the cleaning tank 3 are equalized as shown in FIG.

  The cleaning tank 3 is connected to a decompression means 7 that introduces outside air into the cleaning tank 3 under reduced pressure to restore the pressure in the cleaning tank 3. The return pressure means 7 of the first embodiment introduces outside air into the cleaning tank 3 under reduced pressure via the air supply path 42. An air supply filter 43 and an air supply valve 44 are provided in the air supply path 42. When the air supply valve 44 is opened in a state where the inside of the cleaning tank 3 is decompressed, outside air is introduced into the cleaning tank 3 by a differential pressure. Thus, the pressure in the cleaning tank 3 can be restored.

  The cleaning tank 3 is provided with heating means 10 for heating the cleaning liquid in the cleaning tank 3. The heating means 10 according to the first embodiment heats the cleaning liquid by blowing steam into the cleaning liquid in the cleaning tank 3. Specifically, steam can be supplied to the cleaning tank 3 through a steam supply path 45 from a steam supply source such as a boiler. By opening and closing the steam supply valve 46 provided in the steam supply path 45, it is possible to switch the presence or absence of steam supply into the cleaning tank 3.

  Further, the cleaning tank 3 is provided with a drainage means 11 for discharging the cleaning liquid in the cleaning tank 3. The drainage means 11 of the first embodiment discharges the cleaning liquid in the cleaning tank 3 from the bottom of the cleaning tank 3 through the drainage channel 47. The drainage passage 47 is provided with a drainage valve 48. When the drainage valve 48 is opened in a state where the cleaning liquid is stored in the cleaning tank 3, the cleaning liquid can be naturally led out of the cleaning tank 3.

  The decompression means 6, the decompression means 7, the heating means 10, the drainage means 11, and the water supply means 18 are controlled by the control means 14. The control means 14 is a controller that controls the means 6, 7, 10, 11, 18 based on the detection signals of the sensors 12, 13. Specifically, the water supply pump 5, the chemical injection pump 24, the first water supply valve 22, the second water supply valve 29, the third water supply valve 30, the vacuum pump 24, the air supply valve 28, the steam supply valve 30, the drain valve 32, The steam supply valve 46, the drain valve 47, the pressure sensor 9 and the liquid temperature sensor 10 are connected to the controller 33. And the control means 14 aims at washing | cleaning of the to-be-cleaned object 2 in the washing tank 3 according to a predetermined | prescribed procedure (program) as described below.

  Hereinafter, a cleaning method using the cleaning device 1 of the first embodiment will be specifically described with reference to FIGS. 1 and 2.

<Before starting the water injection process>
In the initial state, there is no cleaning liquid in the cleaning tank 3, the valves 22, 29, 30, 46, 48 other than the air supply valve 44 are closed, and the pumps 5, 21, 24 are not operating. From this initial state, a water injection step S1, a heating step S2, a depressurizing pressure pulse step S3, and a drainage step S4 are sequentially performed.

  Prior to the water injection step S1, the object to be cleaned 2 is placed in the cleaning tank 3, and the first lid 16 of the cleaning tank 3 is closed. However, the object to be cleaned 2 may be placed in the cleaning tank 3 immediately after the water injection step S1. In this case, the first lid 16 of the cleaning tank 3 is placed after the object to be cleaned 2 is placed in the cleaning tank 3. Is closed. In any case, the article to be cleaned 2 is immersed in the cleaning liquid in the cleaning tank 3.

<Water injection process>
The water injection step S <b> 1 is a step of putting a cleaning liquid into the cleaning tank 3 by the water supply means 18. In the first embodiment, with the first water supply valve 22 opened, the water supply pump 21 and the chemical injection pump 24 are operated to put the cleaning liquid into the cleaning tank 3. A desired amount of cleaning agent is added to the water supplied into the cleaning tank 3 by the operation of the chemical injection pump 24. In the water injection step S <b> 1, when the first lid 16 of the cleaning tank 3 is closed, the air in the cleaning tank 3 is discharged from the air supply path 42 along with the water injection to the cleaning tank 3.

  When a liquid level sensor (not shown) provided in the cleaning tank 3 detects that the cleaning liquid has been stored up to a predetermined water level in the cleaning tank 3, water supply by the water supply means 18 is stopped. Specifically, the water supply valve 22 is closed and the water supply pump 21 and the chemical injection pump 24 are stopped, and the process proceeds to the next step.

<Heating process>
The heating step S2 is a step of heating the cleaning liquid in the cleaning tank 3 to the depressurization pressure start temperature. Specifically, the cleaning liquid is heated by the heating means 10 until the cleaning liquid reaches the depressurization pressure start temperature. In the first embodiment, the steam supply valve 46 is opened and steam is blown into the cleaning liquid in the cleaning tank 3 to heat the cleaning liquid. During this steaming, the temperature of the cleaning liquid is monitored by the liquid temperature sensor 13. When the cleaning liquid reaches the depressurization pressure start temperature, the steam supply valve 46 is closed and the process proceeds to the next step.

  The starting pressure of the decompression pressure pulse is not particularly limited. However, when the dirt of the article 2 to be washed is blood dirt, the protein is thermally deformed and fixed when the dirt exceeds 60 ° C. The decompression pressure starting temperature is preferably 60 ° C. or lower, and more preferably 50 ° C. or lower. In the first embodiment, the depressurization pressure start temperature is set to 50 ° C., for example.

<Reducing pressure pulse process>
In the depressurization pressure pulse process (which can be referred to as a reduced pressure boiling cleaning process) S3, the depressurization in the cleaning tank 3 is continued so that the cleaning liquid continues to boil until the cleaning liquid in the cleaning tank 3 reaches the end pressure of the depressurization pressure pulse. Is planned. During this time, during the boiling of the cleaning liquid, the operation of instantaneously restoring the pressure in the cleaning tank 3 at a predetermined timing and temporarily interrupting the boiling of the cleaning liquid is repeated. In this way, the pressure reduction and the instantaneous return pressure are repeated. The end pressure of the decompression pressure pulse is not particularly limited. However, when the cleaning temperature is lowered, the cleaning effect is reduced, and therefore, the temperature is preferably 20 ° C. or higher, and more preferably 25 ° C. or higher.

  More specifically, in the depressurization pressure pulse step S3, the operation of the decompression means 6 is continued to gradually reduce the pressure in the cleaning tank 3, thereby continuing the boiling of the cleaning liquid. However, during this time, the temperature of the cleaning liquid is monitored by the liquid temperature sensor 13, and the pressure inside the cleaning tank 3 is temporarily restored by the decompression means 6 every time the temperature of the cleaning liquid decreases by a predetermined amount. The pressure in the cleaning tank 3 by the pressure reducing means 6 may be reduced by operating the vacuum pump 24 with the air supply valve 44 closed and the second water supply valve 29 and the third water supply valve 30 opened. Further, the instantaneous return pressure up to the set pressure by the return pressure means 7 may be performed by opening the air supply valve 44. Even during the return pressure, the decompression means 6 may remain activated. Then, after opening the air supply valve 44 to restore the pressure in the cleaning tank 3 and interrupting the boiling of the cleaning liquid, the air supply valve 44 is closed again to reduce the pressure in the cleaning tank 3 and the boiling of the cleaning liquid. Figured.

  Such a pressure reduction pulse step S3 is performed until the cleaning liquid reaches the pressure reduction pulse end temperature. The end pressure of the decompression pressure pulse is not particularly limited, but is set to 30 ° C., for example.

(Operation and effect of the first embodiment in the pressure reduction pulse process)
As described above, in the depressurization pressure pulse step S3, the depressurization due to the operation of the depressurization means 6 and the return pressure due to the operation of the depressurization means 7 are repeated, and the cleaning liquid in the cleaning tank 3 boils. When the cleaning liquid is boiled, fine droplets of the cleaning liquid and fine foreign matters adhering to the object to be cleaned flow out from the cleaning tank 3 toward the heat exchanger 4 in the gas. In addition, the cleaning liquid flows out from the cleaning tank 3 as a vapor during decompression.

  Of the foreign matters flowing out from the cleaning tank 3, those having a large diameter are first captured by the pre-filter 37. As a result, the amount of foreign matter captured by the demister 8 is reduced, and the regeneration timing of the demister 8 can be delayed.

  The fine foreign matter that flows out without being captured by the prefilter 37 is removed by the demister 8. As a result, clogging of the minute gaps in the plate heat exchanger 4 due to fine foreign matters is prevented. As a result, a decrease in the heat exchange capability of the plate heat exchanger 4 due to clogging of minute foreign matter is prevented, pressure can be reduced in a short time, and the cleaning time can be shortened.

  When the fine foreign matter captured by the demister 8 reaches a predetermined amount, the second lid 39 is opened, the demister 8 is taken out of the second main body 38 and washed to remove the fine foreign matter. Instead of cleaning the demister 8, a cleaned or new demister 8 may be mounted on the second body 38.

  The pre-filter 37 is also periodically cleaned and regenerated by removing the first lid 16 of the cleaning tank 3.

  In addition, the cleaning liquid and the microdroplet of the cleaning liquid flowing out from the cleaning tank 3 are captured by the demister 8 of the gas-liquid separator 9 and the cleaning liquid is separated from the gas. The separated cleaning liquid falls as droplets and is stored at the bottom of the second container body 37. The stored cleaning liquid is returned to the cleaning tank 3 by the principle of siphon and used for cleaning. With the function of separating the cleaning liquid by the demister 8 and the function of refluxing the separated cleaning liquid, it is possible to reduce the amount of cleaning liquid and cleaning agent that are wasted out of the apparatus, reduce the replenishment amount of the cleaning liquid, and use the cleaning liquid and the cleaning agent. Can be greatly reduced.

  Further, the cleaning liquid separating function by the demister 8 prevents the cleaning liquid from flowing out to the downstream side of the gas-liquid separator 9, thereby preventing the clogging of the minute gap through which the gas of the plate heat exchanger 4 flows due to the cleaning liquid, Reduction of the heat transfer surface of the plate heat exchanger 4 due to the cleaning liquid is prevented. By preventing the reduction of the heat transfer surface, a decrease in the steam condensation capacity by the plate heat exchanger 4 is prevented, and the vacuum pump 5 can reduce the pressure in the cleaning tank 3 to a predetermined pressure in a short time. As a result, the cleaning time can be shortened. Moreover, since the pressure reduction to a predetermined pressure can be performed in a short time, the amount of cooling water used in the heat exchanger 4 can be reduced.

  In the vacuum boiling cleaning apparatus of Patent Document 1, cavitation occurs when a cleaning liquid having a temperature equal to or higher than the saturation temperature is sucked into the vacuum pump. In the first embodiment, the separation function of the cleaning liquid by the demister 8 is used. Since the outflow of the cleaning liquid to the downstream side of the gas-liquid separator 9 is prevented, the cavitation is prevented and the vacuum pump 5 is prevented from being damaged.

<Drainage process, etc.>
The subsequent drainage step S4 is a step of returning the pressure in the cleaning tank 3 to atmospheric pressure and discharging the cleaning water in the cleaning tank 3. Specifically, after opening the air supply valve 44 and returning the pressure in the cleaning tank 3 to the atmospheric pressure, the drain valve 47 may be opened to drain the cleaning water. Thereafter, the object to be cleaned 2 is rinsed as desired. After the rinsing process, it is preferable to perform the drying process after draining the washing water. In the drying step, steam is supplied into the cleaning tank 3 to raise the temperature of the object to be cleaned 2, and then the pressure in the cleaning tank 3 is reduced. Alternatively, it is only necessary to evacuate the cleaning tank 3 by the decompression means 6 while warm air is put into the cleaning tank 3 by heat exchange with steam. Thereby, the to-be-cleaned object 2 in the washing tank 3 is dried.

  Next, a second embodiment of the present invention will be described with reference to FIGS. In the following description, the configuration different from that of the first embodiment will be mainly described, and the same configuration is denoted by the same reference numeral and the description thereof is omitted.

  The second embodiment is different from the first embodiment in that the liquid temperature in the cleaning tank 3 is detected, and the liquid temperature sensor 13 for controlling the temperature of the cleaning liquid is used in the depressurization pressure pulse step S3. Reference numeral 14 is configured to notify the regeneration timing of the demister 8 by the display device 49 when the change gradient of the temperature detected by the liquid temperature sensor 13 is equal to or less than the set value.

The operation and effect of the second embodiment will be described with reference to FIG. Referring to FIG. 4, in S21, it is determined whether or not the decompression of the depressurization pressure pulse process S3 is started. If YES is determined, in S22, it is determined whether or not the change gradient of the temperature detected by the liquid temperature sensor 13 is equal to or less than a set value, that is, whether or not the intended liquid temperature decrease due to the reduced pressure has occurred. The set value is previously determined in relation to the degree of clogging of the demister 8 through experiments. If YES is determined in S22, the control means 14 estimates that the demister 8 is clogged, moves to S23, and informs the user and maintenance personnel that the demister 8 needs to be cleaned by the display 49. . In S23, the operation of the cleaning device is automatically stopped simultaneously with the notification of the necessity of cleaning. The stop of the operation of the cleaning apparatus can be configured such that the notification of the necessity of cleaning is preceded and the stop is performed with a predetermined time delay from the notification.

  According to the second embodiment, it is possible to easily know the timing of regeneration or replacement of the demister 8, and it is possible to prevent the cleaning capability of the cleaning device from being lowered. Further, since the liquid temperature sensor 13 used for controlling the temperature of the cleaning liquid is used for notification of the necessity of cleaning, the configuration of the cleaning apparatus can be simplified. Furthermore, the temperature drop gradient of the cleaning liquid at the time of depressurization directly indicates the depressurization performance. Even if the demister 8 is clogged, the cleaning operation can be continued if the predetermined depressurization performance is ensured. From the viewpoint of continuation of the cleaning operation, detection based on the temperature decrease gradient of the cleaning liquid at the time of depressurization is more preferable than the method of detecting the cleaning time of the demister 8 by differential pressure.

  Next, Embodiment 3 of the present invention will be described with reference to FIG. In the following description, the configuration different from that of the first embodiment will be mainly described, and the same configuration is denoted by the same reference numeral and the description thereof is omitted.

  The third embodiment is different from the first embodiment in that the demister 8 is not taken out from the gas-liquid separator 9, the second lid 39 is removed, and the cleaning liquid for removing foreign matters is ejected by the cleaning means 50 such as a cleaning hose. Thus, the configuration is such that the fine foreign particles adhering to the demister 8 are removed. When the cleaning means 50 is used for cleaning, the drainage valve 48 is opened to open the drainage valve 48, so that the removed foreign matter is discharged through the communication pipe 41-drainage path 47. It is connected to the upstream side of the valve 48.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. In the following description, the configuration different from that of the first embodiment will be mainly described, and the same configuration is denoted by the same reference numeral and the description thereof is omitted.

  The fourth embodiment is different from the first embodiment in the following configuration. In the first embodiment, the air supply path 42 of the decompression means 7 is directly connected to the cleaning tank 3, but in the fourth embodiment, it is connected to the outlet side space 33 of the second container body 38 of the gas-liquid separator 9. ing.

  According to the configuration of the fourth embodiment, when the pressure is restored, an airflow is formed in which outside air sequentially flows through the air supply path 42, the outlet side space 33, the demister 8, and the gas inlet 34 into the cleaning tank 3. At that time, a part of the fine foreign matter captured by the demister 8 is removed by the air flow indicated by a one-dotted line arrow A in FIG. 6 and falls into the second container body 38. Thus, since the demister 8 is cleaned by the air flow every time the pressure is restored, the regeneration or replacement time of the demister 8 can be delayed.

  The cleaning apparatus of the present invention is not limited to the configurations of the first to fourth embodiments, and can be changed as appropriate. In particular, the method of repeating the decompression and the decompression in the decompression pressure pulse step S3 can be changed as appropriate.

  In the cleaning device of the above embodiment, cleaning by ultrasonic vibration may be added. That is, an ultrasonic vibrator may be further installed in the cleaning tank 3. For example, in the heating step S2, cleaning by ultrasonic vibration is preferably performed. The heating step S2 only heats the cleaning liquid and does not contribute to cleaning. Therefore, by applying ultrasonic vibration to the cleaning liquid in this step, the object to be cleaned 2 is ultrasonically cleaned and the cleaning effect is further improved. be able to.

DESCRIPTION OF SYMBOLS 1 Cleaning apparatus 2 Object to be cleaned 3 Cleaning tank 4 Heat exchanger 5 Vacuum pump 6 Pressure reducing means
7 Pressure recovery means 8 Demister 9 Gas-liquid separator 13 Liquid temperature sensor 14 Control means 31 Container 32 Inlet side space 33 Outlet side space 34 Gas inlet 35 Gas outlet 36 Liquid outlet 42 Air supply path
49 Display

Claims (2)

A cleaning tank in which the cleaning liquid is stored, and an object to be cleaned is immersed in the cleaning liquid; a heat exchanger that condenses the gas in the cleaning tank; and a vacuum pump provided downstream of the heat exchanger; Pressure reducing means for sucking and discharging to the inside of the cleaning tank, pressure reducing means for introducing outside air into the pressure-reduced cleaning tank and returning the pressure inside the cleaning tank, the pressure reducing means and the pressure reducing means In a cleaning apparatus comprising: control means for controlling the boiling of the cleaning liquid in the cleaning tank by controlling the reduced pressure and the return pressure by controlling
The heat exchanger is composed of a plate heat exchanger that cools the gas with cooling water,
Upstream of the heat exchanger, the cleaning solution, the micro-droplets and fine foreign matter of the cleaning liquid contained in the gas is separated from the gas by the demister, e Bei the gas-liquid separator to return the separated liquid to the cleaning tank,
The gas-liquid separator includes a container configured separately from the heat exchanger, and a demister arranged so as to partition the inside of the container into an inlet side space and an outlet side space, A gas inlet for introducing the gas from the cleaning tank into the inlet side space, and a gas outlet for flowing the gas after separating the cleaning liquid, cleaning liquid microdroplets and fine foreign matters by the demister toward the heat exchanger; A liquid outlet for returning the liquid separated by the demister to the washing tank, and configured to regenerate or replace the demister,
A liquid temperature sensor for detecting the liquid temperature in the cleaning tank is provided,
The cleaning apparatus according to claim 1, wherein when the change gradient of the temperature detected by the liquid temperature sensor at the time of the pressure reduction becomes equal to or less than a set value, the control unit notifies the regeneration or replacement timing of the demister . Claims wherein connecting the air supply passage of pressure recovery section to the outlet side space, the air supply passage, said outlet space, the demister, characterized in that pressure recovery the cleaning tank the gas inlet sequentially through to the Item 2. The cleaning device according to Item 1 .

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