JP2008036595A - Solvent washing apparatus provided with solvent recovery apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solvent washing apparatus provided with a solvent recovery apparatus with a consumption amount of the solvent capable of sufficiently washing and drying a part and a part assembly (work) in a short time, continuously and efficiently performing recovery of the solvent for a long period of time and polluting no environment. <P>SOLUTION: The solvent washing apparatus is provided with a plurality of washing tanks 11-13 for washing the work with the solvent to remove an oil component and a particle deposited on the work and immersing the work in the solvent liquid to perform washing in order to dry the work, and a vapor drying tank 20 for washing and drying the work coming out from the final stage washing tank 13 of these washing tanks by a solvent vapor. The solvent washing apparatus is further provided with an air-tight closed type complete drying tank 30 for completely drying the work coming out from the vapor drying tank 20 in the air-tightly closed chamber, and the solvent recovery apparatus 40 for sucking, liquefying and recovering the solvent vapor with the raised gas concentration generated in the air-tightly closed type complete drying tank 30. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The invention of the present application relates to a solvent cleaning apparatus, and uses a solvent to clean various parts and parts assemblies (workpieces), which are intermediate products generated in the production line of a precision equipment manufacturing plant such as OA equipment, and adheres to these works. The present invention relates to a solvent cleaning apparatus that removes oil and particles to be dried and dries these workpieces, and more particularly, to a solvent cleaning apparatus including a solvent recovery apparatus that recovers the solvent with high recovery efficiency.

  Since this type of parts and parts assembly requires high processing accuracy and assembly precision, oil such as cutting cooling oil, cutting chips (chips), and particles such as general dust that adhere to the surface of these parts are also required. , Their complete removal is sought. In general, as a method of cleaning machine parts and component assemblies, a water cleaner and a solvent cleaner are conventionally used.

  Since the water washer uses pure water or ultrapure water as the cleaning liquid, it is relatively easy to obtain water as the cleaning liquid, and maintenance is easy to increase the number of stages in the cleaning tank. While the cost is relatively low and environmentally friendly, it is easy to rust, difficult to dry, long tact time, poor productivity, and detergent must be used to remove oil. There is a demerit that it is necessary to remove detergent in addition to oil stains, and pure water equipment is necessary, but at present, for the purpose of removing particles and ion stains, semiconductor parts, electronic parts, Used only for final cleaning of electromechanical parts.

  On the other hand, in order to remove oil and particles adhering to these components and component assemblies, a solvent cleaning machine is generally used. The solvent in this case is required to have properties such as high oil content resolution, high wettability compared to water, and good evaporability (dryability). Freon, trichlene, trichloroethane, hydrocarbon solvents and the like are used. FIG. 10 shows a general configuration of such a solvent cleaning machine.

  In FIG. 10, a conventional solvent cleaner 010 includes a plurality of cleaning tanks 011, 012, 013... And a vapor tank 020. Many of the plurality of cleaning tanks 011, 012, 013... Have an ultrasonic oscillator 025 at the bottom. Therefore, the workpieces (W) such as various parts and parts assemblies that are intermediate products manufactured through a predetermined production process are put together in a basket 026, and the basket 026 is suspended by the hanger 027. Are sequentially passed through these cleaning tanks 011, 012, 013... And a vapor tank 020 (see arrows A 1 to A 4).

  First, the work is carried into the first cleaning tank 011 and immersed therein, and the oil and particles adhering to the work are physically and chemically absorbed while receiving vibration of the solvent liquid excited by the ultrasonic oscillator 025. Separated. Here, physical separation is separation by physical force due to cavitation (cavity fracture) generated by vibration of solvent liquid and physical force due to solvent wettability. , Separation by chemical change due to the substance resolution of the solvent. Such oil and particle separation action is repeated a plurality of times in a plurality of stages of cleaning tanks.

  In this way, the workpieces that have passed through the plurality of cleaning tanks 011, 012, 013... Are finally carried into the vapor tank 020, where washing with solvent vapor and drying are performed. In the vapor tank 020, the solvent liquid stored in the liquid tank at the bottom of the tank is heated to a temperature higher than the solvent vapor pressure temperature by the heater 021, and the generated steam heats the work and the work itself is cooled. The solvent condenses on the work surface, and the condensate of this solvent still adheres to the work surface to wash away and remove oil, particles and other dirt.

  A cooler 022 in which a cooling pipe is wound a plurality of times is attached to the upper inner peripheral wall of the vapor tank 020, and the vaporized solvent condensed by the work and the solvent vapor rising from the vapor liquid tank It is cooled by this cooler 022, condensed, and collected in a basket 023 below the cooler 022. Thus, the work is dried when the solvent condensed by the work in the vapor tank 020 is vaporized.

  The condensate collected in the trough 023 is led from there to a water separator 024 outside the tank, and the solvent liquid obtained by separating water in this water separator 024 is returned again to the final stage washing tank 01N. . The solvent tank overflows from the cleaning tank 01N that has received the regenerated solvent liquid and has an increased liquid level, and sequentially flows into the preceding cleaning tanks 01N-1, 01N-2,. (See arrows B1 and B2), the solvent solution in these washing tanks is replaced with a fresher solvent solution. In order to facilitate the return of such overflowing solvent liquid to the pre-stage washing tank, a plurality of washing tanks 011, 012, 013..., As shown in FIG. The liquid level is lowered as much as possible.

  However, in such a conventional solvent washer 010, generally, the consumption of the solvent is large and it is difficult to dry the workpiece only by the vapor tank 020. The reason for this is that the specific heat of the workpiece is generally small, so that the workpiece is immediately cooled by the latent heat of vaporization of the solvent adhering to the workpiece and the solvent evaporates, and the solvent adhering to the workpiece remains without evaporating. This is because, in particular, the work is cooled before the solvent accumulated in the concave portion or the blind hole evaporates, and the work is carried out of the vapor tank 020 while the solvent remains.

  As described above, if the work cannot be completely dried in the determined washing machine, the work must be naturally evaporated and dried outside the washing machine after the work is unloaded from the washing machine. However, such spontaneous evaporation and drying of the work outside the washing machine causes the solvent to be emitted into the atmosphere, which may cause environmental pollution, and the solvent is recovered for release to the atmosphere. In addition, the solvent consumption is further increased. In order to avoid the occurrence of these problems, it is a rule that the work should be dried in the washing machine.

In order to solve these problems, the applicant of the present invention can sufficiently clean and dry the work in a solvent washer in a short time, thereby almost completely removing oil and particles adhering to the work. In addition, a solvent washer was invented with high solvent recovery efficiency, low solvent consumption, and no environmental pollution (Patent Document 3). However, even in this case, it is difficult to say that the solvent recovery is still sufficient. For this solution, for example, even if the solvent gas is introduced into the heat exchanger and cooled and condensed to recover the solvent liquid, Since the solvent gas that flows into the exchanger inevitably contains moisture in the atmosphere, if the continuous operation is performed, the inside of the heat exchanger will be frosted over time, and in order to defrost it. The recovery operation had to be stopped periodically and the efficiency was poor. Therefore, in order to be able to condense and recover the solvent gas continuously and efficiently over a long period of time, there are still points to be improved.
JP-A-7-265817 JP-A-8-039019 Japanese Patent Laid-Open No. 2003-305417

  The invention of the present application solves the above-mentioned problems of the conventional solvent washer, and various parts and parts assemblies (workpieces) that are intermediate products generated in the production line of a precision equipment manufacturing factory such as OA equipment. Can be sufficiently cleaned and dried in a solvent cleaning device in a short time, thereby further removing oil and particles adhering to the workpiece, and solvent recovery continuously and efficiently over a long period of time. It is an object of the present invention to provide a solvent cleaning apparatus equipped with a solvent recovery apparatus that can be carried out easily and does not pollute the environment with low solvent consumption.

The above-described problems can be solved by the following invention described in each claim of the present application.
That is, the invention described in claim 1 is a method in which a workpiece is washed with a solvent to remove oil and particles adhering to the workpiece, and the workpiece is immersed in a solvent solution in order to dry the workpiece. A solvent drying apparatus comprising: a plurality of cleaning tanks for cleaning; and a steam drying tank for cleaning and drying the workpiece that has exited the final stage cleaning tank among the plurality of cleaning tanks with a solvent vapor. The closed-type complete drying tank that completely drys the work that has left the tank in a sealed room, and the solvent vapor with increased gas concentration generated in the closed-type complete drying tank is sucked, liquefied, and collected. The solvent cleaning apparatus further includes a solvent recovery apparatus. The solvent cleaning apparatus includes the solvent recovery apparatus.

Since the invention described in claim 1 is configured as described above, the following effects can be obtained.
Workpieces that have been cleaned with solvent through multiple cleaning tanks, finished and dried with solvent vapor through vapor drying tanks, and removed oil and particles, then enter a closed-type complete drying tank where they are sealed Heated and dried in the chamber, the solvent remaining on the surface of the workpiece, especially the concave portions and blind holes, which are difficult to pump out, is evaporated and completely removed. In this way, the workpiece can be completely dried.

  Moreover, the solvent vapor separated and evaporated from the workpiece in this way and evaporated to increase the gas concentration is then sucked into the solvent recovery device, where it is liquefied and recovered. Is significantly improved, and the consumption of the solvent can be greatly reduced. Moreover, it does not pollute the environment.

  Further, the invention described in claim 2 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 1, wherein the hermetic complete drying tank is a heater for heating and drying the workpiece therein. And a gas agitation fan, and the solvent vapor generated in the closed complete drying tank is agitated by the gas agitation fan and diffused into the tank.

  With this configuration, the invention described in claim 2 can quickly and efficiently perform heating and drying of the workpiece in the closed type complete drying tank.

  Further, the invention described in claim 3 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 1, wherein the hermetic type complete drying tank is connected to the inside through the gas suction port and the gas discharge port. The closed circulation path is provided with a blower fan, a heater, and a filter. The solvent vapor sucked by the blower fan from the gas suction port is heated by the heater, and the filter And is discharged from the gas discharge port into the sealed complete drying tank.

  According to the third aspect of the present invention, in this configuration, the warm air as the drying heat source generated by heating by the heater is reheated by the heater, purified by the filter, and regenerated, and is completely sealed. The work can be heated and dried more quickly and more efficiently while circulating in the tank and preventing reattachment of particles and the like to the work.

  Furthermore, the invention described in claim 4 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to any one of claims 1 to 3, wherein the solvent recovery apparatus is generated in a closed type complete drying tank. A precooler that sucks and pre-cools the solvent vapor having an increased gas concentration, a compressor that sucks and compresses the solvent vapor that exits the pre-cooler, and a pressure that is discharged from the compressor. First and second heat exchangers for cooling and liquefying the solvent vapor, recovery tanks for recovering the solvent liquid exiting the first and second heat exchangers, and at least the first and second heat exchangers The first and second heat exchangers are connected in series to the flow of the solvent vapor, and the series connection is connected to the heat exchanger. It is possible to switch alternately between upstream position and downstream position. In synchronism with this position change, while one heat exchanger located downstream of the series connection cools the pressurized solvent vapor and continues the liquefaction cooling operation, the series The other heat exchanger located on the upstream side of the connection is characterized in that the cooling operation is interrupted and the switching operation is alternately performed so as to continue the thawing operation for defrosting itself.

  According to this configuration, the first and second heat exchangers included in the solvent recovery device are connected in series with respect to the flow of the solvent vapor, and the upstream side of the series connection is provided. Since the solvent vapor cooling operation and the self thawing operation are alternately switched between the position and the downstream position, the solvent recovery is continuously and efficiently performed for a long time. Can do.

  Further, the invention described in claim 5 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 4, wherein one of the heat exchangers is supplied with the refrigerant gas exiting the refrigerator, The other heat exchanger is characterized in that the input of an external heat source is blocked.

  According to the fifth aspect of the present invention, with this configuration, the heat stored in the solvent vapor itself is used for the defrosting operation of the other heat exchanger of the first and second heat exchangers, and the external heat source Therefore, the solvent can be recovered efficiently and economically.

  According to a sixth aspect of the present invention, there is provided a solvent cleaning apparatus comprising the solvent recovery apparatus according to the fourth aspect, wherein the first and second heat exchangers are first and second external heaters. Each of the heat exchangers is supplied with refrigerant gas exiting the refrigerator, and the other heat exchanger has an external heat source generated by the other external heater provided in the other heat exchanger. When the other heat exchanger interrupts the cooling operation and continues the defrosting operation to defrost itself, the external heat source generated by the other external heater performs the defrosting operation of the other heat exchanger. It is characterized by being supported.

  According to the sixth aspect of the present invention, the heat stored in the solvent vapor itself is used for the defrosting operation of the other heat exchanger of the first and second heat exchangers. While the external heat source generated by the other external heater included in the other heat exchanger is turned on and the other heat exchanger interrupts the cooling operation and continues the thawing operation to defrost itself, the external heat source Since it is designed to support the thawing operation of the other heat exchanger, it is possible to forcibly perform its own thawing in the other heat exchanger in a short time and better prevent its freezing. In addition, heat exchange in the other heat exchanger can be performed efficiently from start to finish, and solvent recovery can be performed more efficiently.

  Furthermore, the invention described in claim 7 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to any one of claims 1 to 3, wherein the solvent recovery apparatus is generated in a closed type complete drying tank. A precooler that sucks and pre-cools the solvent vapor having an increased gas concentration, a compressor that sucks and compresses the solvent vapor that exits the pre-cooler, and a pressure that is discharged from the compressor. First and second heat exchangers for cooling and liquefying the solvent vapor, recovery tanks for recovering the solvent liquid exiting the first and second heat exchangers, and at least the first and second heat exchangers The first and second heat exchangers are connected in parallel to the flow of the solvent vapor, and one of the heat exchanges is provided. While the vessel continues the cooling operation to cool and liquefy the pressurized solvent vapor, Square heat exchanger interrupts the cooling operation, the so in a state of being separated from the flow of the solvent vapor to continue the thawing operation for performing self-defrosting, is characterized by being operated alternately switched.

  According to the seventh aspect of the present invention, with this configuration, the first and second heat exchangers provided in the solvent recovery device are connected in parallel to the flow of the solvent vapor, so that the cooling operation of the solvent vapor and the self Therefore, the solvent recovery can be performed continuously and efficiently over a long period of time.

  Further, the invention described in claim 8 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 7, wherein one of the heat exchangers includes an extremely cold refrigerant that has exited the expansion valve of the refrigerator. The gas is supplied, and the other heat exchanger is supplied with a high-temperature refrigerant gas exiting the compressor of the refrigerator.

  In the invention described in claim 8, because of this configuration, the high-temperature refrigerant gas exiting the compressor of the refrigerator is used as the heat source for the self-defrosting operation in the other heat exchanger. There is no need for an external heat source, and the equipment configuration of the solvent recovery apparatus can be relatively simple.

  The invention described in claim 9 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 7, wherein the first and second heat exchangers are the first and second external heaters. Each of the heat exchangers that continue the cooling operation is supplied with the refrigerant gas that has exited the refrigerator, and the other heat exchanger that interrupts the cooling operation has the other heat exchanger that the other heat exchanger has An external heat source generated by the external heater is input.

  According to the ninth aspect of the present invention, with this configuration, an external heat source generated by the other external heater provided in the other heat exchanger is input as a heat source to the self-thawing operation in the other heat exchanger. Therefore, the self-defrosting in the other heat exchanger can be forcibly performed in a short time to prevent icing, and the heat exchange in the other heat exchanger can be performed efficiently from start to finish. As a result, the solvent can be recovered more efficiently.

  Further, the invention described in claim 10 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 7, wherein the first and second heat exchangers are the first and second external heaters. One of the heat exchangers is supplied with cryogenic refrigerant gas exiting the expansion valve of the refrigerator, and the other heat exchanger is supplied with high-temperature refrigerant gas exiting the compressor of the refrigerator. And the external heat source generated by the other external heater provided in the other heat exchanger is turned on, while the other heat exchanger interrupts the cooling operation and continues the defrosting operation to defrost itself, An external heat source generated by the other external heater supports the thawing operation of the other heat exchanger.

  According to the invention described in claim 10, with this configuration, the self-defrosting operation in the other heat exchanger is performed by using the high-temperature refrigerant gas exiting the compressor of the refrigerator as the heat source, and the other heat exchanger. Since the external heat source generated by the other external heater provided in is supplied, the self-defrosting in the other heat exchanger is forcibly performed in a shorter time to further prevent icing. Even if the solvent recovery is performed continuously for an extremely long time, the heat exchange in the other heat exchanger is efficiently performed from beginning to end, and the solvent recovery can be performed more efficiently.

  The invention described in claim 11 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to claim 9 or 10, wherein the first and second heat exchangers are in one common tank. The tank also serves as a solvent liquid recovery tank. A partition wall is provided between the first heat exchanger and the second heat exchanger, and heat exchange in each heat exchanger is performed. It is characterized by the fact that the actions do not interfere with each other.

  According to the invention described in claim 11, with this configuration, the solvent cleaning apparatus can be configured in a compact manner, the manufacturing cost can be reduced, and heat exchange in both heat exchangers can be efficiently performed. .

  Furthermore, the invention described in claim 12 is the solvent cleaning apparatus provided with the solvent recovery apparatus according to any one of claims 9 to 11, wherein the first and second heat exchangers are finned tubes. It is characterized by comprising a heat exchanger.

  The invention described in claim 12 can obtain a structure in which the first and second heat exchangers are hard to freeze by using the finned tube heat exchanger having excellent heat exchange performance. This makes it possible to recover the solvent more efficiently.

  As described above, according to the solvent cleaning apparatus provided with the solvent recovery apparatus of the present invention, it is cleaned with a solvent through a plurality of cleaning tanks, cleaned and dried with a solvent vapor through a steam drying tank, Next, the workpiece that has been almost removed enters the sealed complete drying tank, where it is heated and dried in a sealed room, where it is difficult to pump out the surface of the workpiece, especially concave parts and blind holes. The remaining solvent is evaporated together with oil and dust and completely removed. In this way, the workpiece can be completely cleaned and dried.

  Moreover, the solvent vapor that has been separated from the work in this way, evaporated, and gas concentration has been increased is then sucked into the solvent recovery device, where it is liquefied and recovered, so that the solvent recovery efficiency is improved. It can be remarkably improved and the consumption of the solvent can be greatly reduced. Moreover, it does not pollute the environment.

In particular, the solvent recovery apparatus is provided with first and second heat exchangers, these heat exchangers are connected in series or in parallel, and one heat exchanger cools the solvent vapor. While the cooling operation to liquefy is continued, the other heat exchanger interrupts the cooling operation and is alternately switched to continue the thawing operation to defrost itself, so that the solvent recovery is continued for a long time. Can be done efficiently, efficiently and economically.
In addition, various effects as described above can be achieved.

  Washing the workpiece with a solvent to remove oil and particles adhering to the workpiece, and in order to dry the workpiece, a plurality of washing tanks that are immersed in a solvent solution and washed, and a plurality of the washing tanks The solvent cleaning apparatus provided with a steam drying tank for cleaning and drying the work exiting the final stage cleaning tank with solvent vapor completely seals the work exiting the steam drying tank in a sealed room The apparatus further includes a complete drying tank and a solvent recovery device that sucks, liquefies, and recovers the solvent vapor having an increased gas concentration generated in the sealed complete drying tank.

  This solvent recovery device sucks solvent vapor with increased gas concentration generated in a closed complete drying tank and precools it, and sucks and vaporizes the solvent vapor exiting the precooler. , A first and second heat exchanger that cools and liquefies pressurized solvent vapor exiting the compressor, and a solvent exiting the first and second heat exchangers A recovery tank for recovering the liquid, and a refrigerator for supplying refrigerant gas alternately or simultaneously to at least the first and second heat exchangers, wherein the first and second heat exchangers include a solvent Connected in series or parallel to the steam flow, one heat exchanger cools pressurized solvent vapor and continues the cooling operation to liquefy while the other heat exchanger interrupts the cooling operation Switch to alternate so that the thawing operation to defrost itself continues. And shall.

  Here, as a heat source in the cooling operation of the solvent vapor in one heat exchanger, it is assumed that the refrigerant gas or the cryogenic refrigerant gas exiting the refrigerator is used, and in the self-thawing operation in the other heat exchanger As the heat source, the heat retained by the solvent vapor itself, the high-temperature refrigerant gas discharged from the compressor of the refrigerator, the external heat source generated by the external heater, or the like is used alone or in combination.

Next, a first embodiment (embodiment 1) of the present invention will be described.
FIG. 1 is a schematic configuration diagram of a portion of the solvent cleaning apparatus provided with the solvent recovery apparatus according to the first embodiment, excluding the solvent recovery apparatus, and FIG. 2 is a sealed complete drying tank further provided in the solvent cleaning apparatus. FIG. 3 is a diagram showing another modification of the sealed complete drying tank, and FIG. 4 is a general view of a solvent recovery apparatus common to the solvent cleaning apparatus of each embodiment of the present invention. FIG. 5 is a schematic configuration diagram, and FIG. 5 is a solvent recovery device provided in the solvent cleaning device of the first embodiment (hereinafter, may be abbreviated as “solvent recovery device of the first embodiment”. The same applies to other embodiments). It is a typical schematic block diagram.

  The solvent cleaning apparatus provided with the solvent recovery apparatus according to the first embodiment is various parts and parts assemblies (hereinafter collectively referred to as “intermediate products”) generated in a production line of a manufacturing plant for precision equipment such as OA equipment. The “work” is indicated by the symbol W in FIG. 1) and is washed with a solvent, and oil such as cutting cooling oil or cutting waste (chip) adhering to these workpieces, It is used to remove particles such as general dust, dry these works, and recover the solvent used for cleaning with high recovery efficiency.

  As shown in FIG. 1 and FIG. 4, the overall configuration is generally a first to third stage cleaning tanks 11 to 13 and a vapor tank (steam drying tank) following the third stage cleaning tank 13. 20, a sealed complete drying tank 30 following the vapor tank 20, and a solvent recovery device 40 following the sealed complete drying tank 30.

The detailed structure and operation of the first to third stage cleaning tanks 11 to 13 and the vapor tank 20 are described with reference to the first to third stage cleaning tanks 011 in the conventional solvent washer 010 shown in FIG. ˜013, substantially the same as the detailed structure and operation of the vapor tank 020, the first to third stage washing tanks 11 to 13 and the vapor tank 20 are the first to third stages of the conventional solvent washer 010. Since the initial letter 0 of the reference numerals attached to the stage washing tanks 011 to 013 and the vapor tank 020 is simply deleted, the detailed description thereof is omitted.
Reference numeral 10 indicates a solvent washer portion corresponding to the conventional solvent washer 010, which is composed of first to third stage wash tanks 11 to 13 and a vapor tank 20. The number of washing tanks will be increased as necessary.

Here, as described in the explanation of the conventional solvent washer 010, the cleaning and drying of the work in the first to third washing tanks 11 to 13 and the vapor tank 20 generally requires a large amount of solvent consumption. Moreover, it is difficult to dry the workpiece only by the vapor tank 20. The reason for this has been briefly described in the description of the conventional solvent washer 010, but here is a further explanation as follows.
Now, when the solvent liquid stored in the vapor tank 20 is heated and boiled to generate a solvent vapor, the solvent vapor is heavier than air and therefore exists as a vapor phase on the liquid surface. When a workpiece having a temperature lower than the boiling point of the solvent is introduced into the vapor phase, the solvent vapor is condensed on the workpiece surface. The condensed solvent liquid flows down while removing oil and particles adhering to the workpiece surface. In this way, clean solvent is constantly condensed on the surface of the work and flows down to advance the steam. The work is gradually warmed by the steam, and eventually the temperature of the work surface becomes the same as the steam temperature, so that the condensation of the solvent vapor does not occur and the work is dried. The work that has been vapor-dried in this way is slowly pulled up so as not to disturb the vapor phase and is taken out of the vapor tank 20. However, depending on the size and shape of the workpiece, it is difficult to completely dry the workpiece using only the vapor tank 20. If the workpiece is large, it is difficult to warm the surface uniformly and completely dry, and if there are concave portions or blind holes, the workpiece is vaporized before the solvent accumulated in them is completely evaporated. This is because the solvent remains as it is.

  Therefore, in the solvent cleaning apparatus of the first embodiment, the work that has passed through the vapor tank 20 is completely dried, and in order to achieve highly efficient recovery of the evaporated solvent, the sealed complete drying tank 30 immediately after the vapor tank 20. In addition, a solvent recovery device 40 is installed after the sealed complete drying tank 30.

  The closed-type complete drying tank 30 is provided with a heater 32 around its inner peripheral wall, and is installed together with the solvent vapor generated in the first to third cleaning tanks 11 to 13 and the vapor tank 20 in the room ( The workpiece (and the tray that accommodates the workpiece) carried into the tank) is heated in an atmosphere kept at a high temperature by the heater 32 in the completely sealed chamber, and particularly the concave portion or The solvent remaining in the blind hole without being completely evaporated is evaporated together with the dirt, and the workpiece is completely dried. The work completely cleaned and dried in this way is then taken out to the outside and transported to the next step by opening the lid 38 of the closed complete drying tank 30. On the other hand, the newly generated solvent vapor is added, and the indoor solvent vapor whose gas concentration is increased is sent to the solvent recovery device 40 through the pipe 39 in a state of being mixed with high-temperature air. Reference numeral 31 denotes a shutter that partitions the vapor tank 20 and the sealed complete drying tank 30.

The sealed complete drying tank 30 can be modified as shown in FIG.
In this modification, the sealed complete drying tank 30 includes a gas stirring fan 33 therein. Then, the gas agitating fan 33 agitates the solvent vapor having an increased gas concentration in the sealed complete drying tank 30 and diffuses it into the room. Thereby, the heating and drying of the workpiece in the sealed complete drying tank 30 can be performed quickly and efficiently.

Further, the sealed complete drying tank 30 can be further modified as shown in FIG.
In this modification, the sealed complete drying tank 30 includes a closed circulation path 34 that is in fluid communication with the inside thereof via a gas suction port 34a and a gas discharge port 34b. A fan 35, a heater 36, and a filter 37 are provided. Then, warm air containing solvent vapor sucked by the blower fan 35 from the gas suction port 34a is heated by the heater 36, filtered by the filter 37, and discharged into the sealed complete drying tank 30 from the gas discharge port 34b. It has become. By doing in this way, the warm air which becomes the drying heat source generated by heating by the heater 36 is reheated by the heater 36, purified by the filter 37 and regenerated, and the inside of the closed complete drying tank 30 is evenly distributed. It is possible to heat and dry the workpiece more quickly and more efficiently while preventing the particles in the hot air from re-adhering to the workpiece and contaminating the workpiece.

Next, the structure and operation of the solvent recovery device 40 will be described.
As shown in FIG. 4, the solvent recovery device 40 includes a precooler 42, a compressor 43, a heat exchanger unit 50, a separation tank (recovery tank) 54, and a refrigerator 60.
The precooler 42 sucks the solvent vapor having a temperature of about 70 ° C. supplied from the sealed complete drying tank 30 through the pipes 39 and 41, and exchanges heat with the cooling water supplied through the pipe 44. In order to protect the compressor 43, it is cooled to 40 ° C. Next, the compressor 43 sucks the cooled solvent vapor and pressurizes and heats it to a pressure of 0.7 Mpa and a temperature of 70 ° C. in order to increase the concentration of the solvent vapor. Feed into unit 50. The heat exchanger unit 50 heat-exchanges the pressurized and heated solvent vapor and the refrigerant gas supplied from the refrigerator 60 to cool and liquefy the solvent vapor. The mixture of the liquefied solvent and the non-condensable gas is guided to the separation tank 54 through the pipe 53 and the pressure reducing valve 75, where it is separated into the solvent liquid and the non-condensable gas. Then, the solvent liquid is sent from there to the water separator 24 and again used as a cleaning solvent in the first to third cleaning tanks 11 to 13. Further, the non-condensable gas component is exhausted through the pipe 55. Here, as the solvent, a brominated solvent (boiling point 71 ° C.) provided by Dipsol under the trade name SC-52S is used.

  The heat exchanger unit 50 includes a pair of first heat exchanger 51a and second heat exchanger 51b. The reason why the heat exchanger unit 50 includes a pair of heat exchangers is as follows. That is, it is difficult to say that the solvent recovery is still sufficient in the conventional solvent washer. To solve this problem, for example, a heat exchanger is connected to the solvent washer, and the solvent gas is introduced into the heat exchanger and cooled. Even if the solvent liquid is condensed and recovered, the solvent gas flowing into the heat exchanger inevitably contains moisture in the atmosphere. In order to perform thawing, the solvent recovery operation must be periodically stopped in order to perform the thawing, resulting in poor efficiency. Therefore, in order to condense and recover the solvent gas continuously and efficiently over a long period of time, two heat exchangers are provided so that they can be used alternately.

These heat exchangers may be connected in series to the flow of solvent vapor or connected in parallel, but in the first embodiment, they are connected in series, and this The position is switched alternately between the upstream position and the downstream position of the series connection. This will be described in detail with reference to FIG. 5. (1) The flow of the solvent vapor exiting the compressor 43 is changed to a flow indicated by a solid line, and the first heat exchange is performed with respect to this flow. The arrangement and connection pattern are arranged and connected such that the vessel 51a is on the upstream side and the second heat exchanger 51b is on the downstream side, and (2) the flow of the solvent vapor is the flow indicated by the broken line With respect to this flow, the second heat exchanger 51b is on the upstream side and the first heat exchanger 51a is on the downstream side. , Which can be switched alternately.

  When both heat exchangers are set to the arrangement / connection pattern of (1), the refrigerant gas generated by the refrigerator 60 is described later in the second heat exchanger 51b located on the downstream side. Is supplied through a branch refrigerant pipe 61b (shown by a solid line in FIG. 5), where heat exchange between the solvent vapor and the refrigerant gas is performed, and the solvent vapor is cooled, liquefied and recovered. The During this time, the first heat exchanger 51a located on the upstream side only flows the pressurized and heated solvent vapor inside, and the supply of the refrigerant gas is shut off, and the solvent vapor is cooled and liquefied. Cooling operation is interrupted. And the thawing operation which melts and removes the frost that has been cooled to about −15 ° C. and adhered to its own heat transfer wall by the heat of the solvent vapor by continuing the cooling operation at the time of the previous switching operation. continue. By this thawing operation, the temperature of the heat transfer wall surface of the first heat exchanger 51a is recovered to 0 ° C.

  When both heat exchangers are set to the arrangement / connection pattern of (2), the refrigerant gas generated by the refrigerator 60 is described later in the first heat exchanger 51a located on the downstream side. Is supplied through a branch refrigerant pipe 61a (shown by a broken line in FIG. 5), in which heat exchange between the solvent vapor and the refrigerant gas is performed, and the solvent vapor is cooled, liquefied and recovered. The During this time, the second heat exchanger 51b located on the upstream side only flows the pressurized and heated solvent vapor inside, and the supply of the refrigerant gas is cut off to cool and liquefy the solvent vapor. Cooling operation is interrupted. And the thawing | decompression operation which melt | dissolves with the heat | fever of the solvent vapor | steam and removes the frost cooled by having continued the cooling operation at the time of the previous switching operation and adhering to the own heat-transfer wall surface is continued.

  Thus, in the first embodiment, the first and second heat exchangers 51a and 51b are connected in series with respect to the flow of the solvent vapor, and the upstream position and the downstream side of the series connection are connected. In addition, in synchronization with the switching of the position, one of the heat exchangers located on the downstream side of the series connection is supplied with pressurized and heated solvent vapor. While continuing the cooling operation that cools and liquefies, the other heat exchanger located upstream of the series connection interrupts the cooling operation and presses and heats itself to defrost itself with the flowing solvent vapor. In order to continue the thawing operation, the switching operation is alternately performed.

  The first and second heat exchangers 51a and 51b are provided with first and second heaters 52a and 52b (see FIG. 4), respectively, and external heat sources generated by these heaters are connected to these first and second heat exchangers 51a and 51b. Although it may be used to support the thawing operation of the heat exchanger, it is unnecessary in the first embodiment because it is not used.

Here, the structure and operation of the refrigerator 60 will be described in more detail.
In the refrigerator 60, the compressor 62, the condenser 63, and the expansion valves 64a and 64b are installed in this order on the refrigerant circuit in which the refrigerant pipe 61 is bifurcated in the middle to be branched refrigerant pipes 61a and 61b. In addition, the high-temperature refrigerant gas pipes 67a (outward path) and 67b (return path) are branched from between the compressor 62 and the condenser 63. Here, the expansion valve 64a is installed in the branch refrigerant pipe 61a, and the expansion valve 64b is installed in the branch refrigerant pipe 61b. In these branch refrigerant pipes 61a and 61b, switching valves 65a and 65b are installed upstream of the expansion valves 64a and 64b. The condenser 63 exchanges heat with the cooling water supplied from the compressor 72 through the pipe 72 and condenses it into a refrigerant liquid.

  A three-way valve 66 is installed at a location where the high-temperature refrigerant gas pipe 67 a branches from the refrigerant pipe 61. When the three-way valve 66 is opened in the direction of the high-temperature refrigerant gas pipe 67a, a part of the high-pressure and high-temperature refrigerant gas flowing from the compressor 62 in the direction of the condenser 63 flows in the direction of the high-temperature refrigerant gas pipe 67a. . The end of the high-temperature refrigerant gas pipe 67a is switched and connected to one of the branch refrigerant pipes 61a and 61b at a position upstream of the heat exchanger unit 50 by switching valves 68a and 68b. Further, the base end of the high-temperature refrigerant gas pipe 67b is switched and connected to one of the branch refrigerant pipes 61a and 61b at the position downstream of the heat exchanger unit 50 by the switching valves 69a and 69b. .

  However, these high-temperature refrigerant gas pipes 67a and 67b are not used in the first embodiment, and the three-way valve 66 and the four switching valves 68a, 68b, 69a and 69b are all closed in the first embodiment. Has been. Therefore, in the first embodiment, the high-temperature refrigerant gas pipes 67a and 67b, the three-way valve 66, and the four switching valves 68a, 68b, 69a, and 69b may be removed. The high-temperature refrigerant gas pipes 67a, 67b, the three-way valve 66, and the four switching valves 68a, 68b, 69a, 69b are removed from the refrigerator 60, and the branch refrigerant pipes 61a, 61b are not branched from the refrigerant pipe 61. 1 shows a basic configuration of the refrigeration cycle.

  The refrigerator 60 also includes an accumulator 70 on the refrigerant circuit between the compressor 62 and the position where the branch refrigerant pipes 61a and 61b merge on the downstream side of the heat exchanger unit 50, and further includes a condenser 63. The receiver tank 71 is provided on the refrigerant circuit between the refrigerant pipe 61 and the position where the refrigerant pipe 61 is bifurcated on the upstream side of the heat exchanger unit 50 to be the branched refrigerant pipes 61a and 61b. In addition, a plurality of temperature sensors and pressure sensors, various valves controlled by these sensors, and the like are provided at predetermined positions on the refrigerant circuit, but detailed description thereof is omitted.

  Since the refrigerator 60 is configured as described above, in the first embodiment, when both heat exchangers are set to the arrangement / connection pattern of (1), the switching valve 65b is opened. The expansion valve 64b is adjusted to an appropriate opening degree, and the refrigerant gas generated in the refrigerator 60 in the second heat exchanger 51b located on the downstream side (this refrigerant gas passes through the expansion valve 64b). Thereafter, it is obtained by vaporization and expansion.) Is supplied through the branch refrigerant pipe 61b. During this time, the switching valve 65a is closed, and the refrigerant gas is not supplied to the first heat exchanger 51a located on the upstream side.

When both the heat exchangers are set to the arrangement / connection pattern of (2), the switching valve 65a is opened, the expansion valve 64a is adjusted to an appropriate opening degree, and the second position located on the downstream side. The refrigerant gas generated by the refrigerator 60 in the first heat exchanger 51a (this refrigerant gas is obtained by evaporating and expanding after the refrigerant liquid passes through the expansion valve 64a) passes through the branch refrigerant pipe 61a. Supplied. During this time, the switching valve 65b is closed, and the refrigerant gas is not supplied to the second heat exchanger 51b located on the upstream side.
The refrigerator 60 can be configured to be used for generating cooling water supplied to the preliminary cooler 42 through the pipe 44.

Since the solvent cleaning apparatus provided with the solvent recovery apparatus 40 of the first embodiment is configured as described above, the following effects can be achieved.
Workpieces that have been cleaned with a solvent through a plurality of cleaning tanks 11 to 13, finished with a solvent vapor through a vapor tank (steam drying tank) 20 and dried and then removed from oil and particles are then sealed and completely dried. The tank 30 is heated and dried in a sealed chamber, and the solvent remaining on the surface of the workpiece, particularly, the concave portions and blind holes, which are difficult to pump out, is evaporated. Completely removed. In this way, the workpiece can be completely dried.

  Moreover, the solvent vapor that has been separated from the workpiece and evaporated in this way and whose gas concentration has been increased is then sucked into the solvent recovery device 40 where it is liquefied and recovered. It can be remarkably improved and the consumption of the solvent can be greatly reduced. Moreover, it does not pollute the environment.

  Further, the solvent recovery device 40 sucks and preliminarily cools the solvent vapor having an increased gas concentration generated in the closed complete drying tank 30 and the solvent vapor discharged from the precooler 42. Compressor 43 that sucks and compresses to further increase the gas concentration, and first and second heat exchangers that cool and liquefy the pressurized and heated solvent vapor exiting compressor 43 51a, 51b, a separation tank (recovery tank) 54 for recovering the solvent liquid exiting the first and second heat exchangers 51a, 51b, and a refrigerant in the first and second heat exchangers 51a, 51b The first and second heat exchangers 51a and 51b are connected in series with respect to the flow of solvent vapor, and are located upstream of the series connection. And can be switched alternately between downstream position Synchronously with the switching of this position, while one heat exchanger located downstream of the series connection continues the cooling operation to cool and liquefy the pressurized and heated solvent vapor, Since the other heat exchanger located upstream of the series connection interrupts the cooling operation and continues the defrosting operation to defrost itself, the solvent recovery is continued for a long time. Efficient and efficient.

In particular, one of the heat exchangers is supplied with the refrigerant gas that has exited the refrigerator 60, and the other heat exchanger only has solvent vapor flowing therethrough, and the input of an external heat source is interrupted. In the thawing operation of this heat exchanger, the heat retained by the solvent vapor itself is used, and an external heat source is not required, and the solvent can be recovered efficiently and economically.
If the switching operation of the first and second heat exchangers 51a and 51b is continued for a very long time, freezing proceeds in the heat exchanger on the side where the cooling operation is continued, and at the time of the next switching operation. In the case where such a situation occurs, there is a possibility that the freeze will clog the heat exchanger. It is necessary to determine the freezing time that does not reach from the data and set the switching operation time interval appropriately.

  The sealed complete drying tank 30 includes a heater 32 for heating and drying the workpiece and a gas stirring fan 33 inside, and the solvent vapor generated in the sealed complete drying tank 30 is removed from the gas stirring fan. In the case where the agitation is performed by 33 and diffused in the room, heating and drying of the workpiece in the sealed complete drying tank 30 can be performed quickly and efficiently.

  Further, the closed complete drying tank 30 includes a closed circulation path 34 that is in fluid communication with the inside thereof via a gas suction port 34a and a gas discharge port 34b. The closed circulation path 34 includes a blower fan 35 and a heater 36. And a filter 37, the solvent vapor sucked by the blower fan 35 from the gas suction port 34 a is heated by the heater 36, filtered by the filter 37, and the inside of the closed complete drying tank 30 from the gas discharge port 34 b. In this case, the warm air as the drying heat source generated by heating by the heater 36 is reheated by the heater 36, purified by the filter 37, regenerated, and regenerated, and completely sealed. Circulating the tank 30 to prevent the particles from re-adhering to the workpiece, and to heat and dry the workpiece more quickly and efficiently. Can.

Next, a second embodiment (embodiment 2) of the present invention will be described.
FIG. 6 is a schematic schematic configuration diagram of a solvent recovery device provided in the solvent cleaning device of the second embodiment. As illustrated in FIG. 6, the solvent recovery device 40 a included in the solvent cleaning device according to the second embodiment is compared with the solvent recovery device 40 included in the solvent cleaning device according to the first embodiment. In contrast, the first and second heaters 52a and 52b attached to the containers 51a and 51b were not used in the solvent recovery apparatus 40 to support the thawing operation of these heat exchangers, The solvent recovery device 40a is different in that it is used to support the thawing operation of these heat exchangers.

  That is, in the solvent recovery apparatus 40 of the first embodiment, the other heat exchanger that continues the thawing operation for defrosting itself by interrupting the cooling operation for cooling and liquefying the pressurized and heated solvent vapor. However, only the solvent vapor that has been pressurized and heated flows inside, and the external heat source is shut off, and heat exchange between the external heat source and the solvent vapor is also conducted by the heat exchanger by the external heat source. Although heating from the outside of the hot wall was not performed, in the solvent recovery apparatus 40a of Example 2, the other heat exchanger was pressurized and heated in the other heat exchanger. Since the external heat source which the heater of the side attached to this other heat exchanger of the 1st and 2nd heaters 52a and 52b generate | occur | produces in the exterior exists, this other heat exchanger Heats the solvent vapor itself from its internal heat. Kicking with, from the outside, it will be subject to heating by the external heat source. In this way, this external heat source is input to the other heat exchanger and used to support the defrosting / thawing operation by the retained heat of the solvent vapor itself of the other heat exchanger. .

Since the solvent cleaning apparatus including the solvent recovery apparatus 40a of the second embodiment is configured as described above, the following effects can be further achieved.
In the thawing operation of the other heat exchanger of the first and second heat exchangers 51a and 51b, the retained heat of the solvent vapor itself is used, and the other external heater provided in the other heat exchanger While the external heat source generated by 52a or 52b is turned on and the other heat exchanger continues the thawing operation to interrupt the cooling operation and defrost itself, the external heat source defrosts the other heat exchanger. Since it is designed to support the operation, the other heat exchanger can be forced to defrost itself in a short time, and the freezing can be better prevented. Thus, the heat exchange can be performed efficiently from start to finish, and the solvent can be recovered more efficiently.

Next, a third embodiment (embodiment 3) of the present invention will be described.
FIG. 7 is a schematic schematic configuration diagram of a solvent recovery device provided in the solvent cleaning device of the third embodiment. The solvent recovery device 40b included in the solvent cleaning device of the third embodiment is different from the solvent recovery devices 40 and 40a included in the solvent cleaning device of the first and second embodiments in that the first and second heat exchangers 51a and 51b are The solvent recovery devices 40 and 40a are connected in series with the flow of the solvent vapor, whereas the solvent recovery device 40b is different in that it is connected in parallel with the flow of the solvent vapor. ing. Further, as compared with the solvent recovery device 40a included in the solvent cleaning device of Example 2, the first and second heaters 52a and 52b support the thawing operation of these heat exchangers in the solvent recovery device 40a. The solvent recovery device 40b is different in that it is not used to support the thawing operation of these heat exchangers. However, in any one of the solvent recovery devices 40, 40a, 40b, while one of the heat exchangers continues the cooling operation of cooling and liquefying the pressurized and heated solvent vapor, the other heat exchanger However, it is common in that these heat exchangers are alternately switched so that the cooling operation is interrupted and the thawing operation for defrosting itself is continued.

More specifically, in the solvent recovery device 40b included in the solvent cleaning device of the third embodiment, the flow of the solvent vapor exiting the compressor 43 is caused by the flow of each of the first and second heat exchangers 51a and 51b. The heat exchanger is alternately switched and connected. Then, the cryogenic refrigerant gas exiting the expansion valve 64a or 64b of the refrigerator 60 is supplied to the heat exchanger on the side connected to the flow of the solvent vapor, where the solvent vapor and the cryogenic refrigerant gas are supplied. Heat exchange takes place and the solvent vapor is cooled, liquefied and recovered. During this time, the high-temperature refrigerant gas exiting the compressor 62 of the refrigerator 60 is supplied to the heat exchanger on the side that is not connected to the flow of the solvent vapor. Here, the heat transfer wall of the heat exchanger is supplied from the outside. The frost that has been heated and cooled as a result of the heat exchanger continuing the cooling operation during the previous switching operation and adhered to its own heat transfer wall is dissolved and removed by the heat.
That is, the heat exchanger on the side connected to the solvent vapor flow continues the cooling operation of the solvent vapor, and the heat exchanger on the side not connected to the solvent vapor flow continues its thawing operation. Moreover, the first and second heat exchangers 51a and 51b are alternately switched and operated.

  This will be described in more detail with reference to FIGS. 4 and 7. The first and second heat exchangers 51a and 51b are: (1) the flow of the solvent vapor exiting the compressor 43 is a solid line. An arrangement / connection pattern in which the first heat exchanger 51a is connected to the flow of the solvent vapor and the second heat exchanger 51b is disconnected from the flow of the solvent vapor, and (2) The flow is changed to a flow indicated by a broken line, and the second heat exchanger 51b is connected to the flow of the solvent vapor, and the arrangement / connection pattern in which the first heat exchanger 51a is disconnected alternately. To be switched to.

  When both heat exchangers are set to the arrangement / connection pattern of (1), the expansion valve 64a of the refrigerator 60 is connected to the first heat exchanger 51a connected to the flow of the solvent vapor. The discharged cryogenic refrigerant gas is supplied through the branch refrigerant pipe 61a (shown by a solid line in FIG. 7). Here, heat exchange between the solvent vapor and the cryogenic refrigerant gas is performed, and the solvent vapor is cooled. Liquefied and recovered. Meanwhile, in the second heat exchanger 51b separated from the flow of the solvent vapor, the high-temperature refrigerant gas exiting the compressor 62 of the refrigerator 60 is fed with the three-way valve 66, the high-temperature refrigerant gas pipe 67a (outward path), and the switching valve 68b. Is supplied through the branch refrigerant pipe 61b (shown by a solid line in FIG. 7), where the heat transfer wall of the heat exchanger is heated from the outside, and the heat exchanger is cooled during the previous switching operation. The frost that has been cooled by adhering to the operation and adhered to its own heat transfer wall is dissolved and removed by the heat.

  When both heat exchangers are set to the arrangement / connection pattern of (2), the expansion valve 64b of the refrigerator 60 is connected to the second heat exchanger 51b connected to the solvent vapor flow. The cryogenic refrigerant gas that has exited is supplied through the branch refrigerant pipe 61b (indicated by a broken line in FIG. 7), where heat exchange between the solvent vapor and the cryogenic refrigerant gas is performed, and the solvent vapor is cooled. Liquefied and recovered. During this time, in the first heat exchanger 51a separated from the flow of the solvent vapor, the high-temperature refrigerant gas exiting the compressor 62 of the refrigerator 60 is supplied with the three-way valve 66, the high-temperature refrigerant gas pipe 67a (outward path), and the switching valve 68a. Is supplied through the branch refrigerant pipe 61a (indicated by a broken line in FIG. 7), where the heat transfer wall of the heat exchanger is heated from the outside, and the heat exchanger is cooled during the previous switching operation. The frost that has been cooled by adhering to the operation and adhered to its own heat transfer wall is dissolved and removed by the heat.

  The high-temperature refrigerant gas that has alternately passed through the first heat exchanger 51a and the second heat exchanger 51b in this way alternates between the branch refrigerant pipes 61a and 61b and the switching valves 69a and 69b in a state where the temperature is lowered. Then, the refrigerant pipe 61 is returned to the refrigerant pipe 61 through the high-temperature refrigerant gas pipe 67b (return path). The position where the high-temperature refrigerant gas is returned to the refrigerant pipe 61 is a position between the three-way valve 66 and the condenser 63.

Since the solvent cleaning apparatus including the solvent recovery apparatus 40b of the third embodiment is configured as described above, the following specific effects can be achieved.
The first and second heat exchangers 51a and 51b included in the solvent recovery device 40b are connected in parallel to the flow of the solvent vapor, and are alternately switched between the solvent vapor cooling operation and the self-defrosting operation. Therefore, solvent recovery can be performed continuously and efficiently over a long period of time.

  In addition, as a heat source for both the solvent vapor cooling operation in one of the first and second heat exchangers 51a and 51b and the self-defrosting operation in the other heat exchanger, Since the refrigerant gas (extremely cold refrigerant gas and high-temperature refrigerant gas) exiting the refrigerator 60 is used, no other external heat source is required, and the device configuration of the solvent recovery device 40b is relatively simple. Can do.

Next, a fourth embodiment (embodiment 4) of the present invention will be described.
FIG. 8 is a schematic schematic configuration diagram of a solvent recovery device provided in the solvent cleaning device of the fourth embodiment. As compared with the solvent recovery device 40b provided in the solvent cleaning device of Example 3, the solvent recovery device 40c provided in the solvent cleaning device of Example 4 is used as an external heat source of the other heat exchanger that continues its thawing operation. In the solvent recovery device 40b, the high-temperature refrigerant gas exiting the compressor 62 of the refrigerator 60 is used, whereas in the solvent recovery device 40c, the first or second heater provided in each heat exchanger. The difference is that a heat source generating 52a and 52b is used.

  Specifically, referring to FIG. 8, the first and second heat exchangers 51a and 51b are set to the same arrangement / connection pattern as the arrangement / connection pattern (1) in the third embodiment. In this case, the refrigerant gas exiting the expansion valve 64a of the refrigerator 60 is supplied to the first heat exchanger 51a connected to the flow of the solvent vapor through the branch refrigerant pipe 61a (shown by a solid line in FIG. 8). Here, heat exchange between the solvent vapor and the refrigerant gas is performed, and the solvent vapor is cooled, liquefied, and collected. In this respect, the cryogenic refrigerant gas is simply called the refrigerant gas, and there is no difference from the third embodiment.

  On the other hand, as described above, while the first heat exchanger 51a continues the solvent vapor cooling operation, the second heat exchanger 51b disconnected from the flow of the solvent vapor has the second heat exchange. The heat source generated by the second heater 52b included in the heat exchanger 51b is turned on, and the external heat source heats the heat transfer wall of the heat exchanger from the outside, and the heat exchanger performs a cooling operation when performing the previous switching operation. The frost that has been cooled and adhered to its own heat transfer wall is melted and removed by continuing the process. Therefore, in this case, the high-temperature refrigerant gas that has exited the compressor 62 of the refrigerator 60 is not used.

  Further, when the first and second heat exchangers 51a and 51b are set to the same arrangement / connection pattern as the arrangement / connection pattern of (2) in the third embodiment, they are connected to the flow of the solvent vapor. The refrigerant gas exiting the expansion valve 64b of the refrigerator 60 is supplied to the second heat exchanger 51b through the branch refrigerant pipe 61b (shown by broken lines in FIG. 8), where the solvent vapor and the refrigerant gas The solvent vapor is cooled, liquefied and recovered. In this respect, the cryogenic refrigerant gas is simply called the refrigerant gas, and there is no difference from the third embodiment.

  On the other hand, as described above, while the second heat exchanger 51b continues the cooling operation of the solvent vapor, the first heat exchanger 51a disconnected from the flow of the solvent vapor has the first heat exchange. The heat source generated by the first heater 52a included in the heat exchanger 51a is turned on, the external heat source heats the heat transfer wall of the heat exchanger from the outside, and the heat exchanger performs a cooling operation when performing the previous switching operation. The frost that has been cooled and adhered to its own heat transfer wall is melted and removed by continuing the process. Therefore, in this case, the high-temperature refrigerant gas that has exited the compressor 62 of the refrigerator 60 is not used.

  In the solvent recovery apparatus 40c of the fourth embodiment, the first and second heat exchangers 51a and 51b are both constituted by finned tube heat exchangers having excellent heat exchange performance, and one common tank. The tank 73 is also used as a solvent liquid recovery tank. Therefore, a separate separation tank (collection tank) 54 as shown in FIG. 4 is unnecessary. Further, a partition wall 74 is provided between the first heat exchanger 51a and the second heat exchanger 51b so that the heat exchange actions in the heat exchangers do not interfere with each other. Yes.

Since the solvent cleaning apparatus including the solvent recovery apparatus 40c of the fourth embodiment is configured as described above, the following specific effects can be achieved.
As the heat source, the other external heater 52a or 52b provided in the other heat exchanger is generated as a heat source for the self-defrosting operation in the other heat exchanger of the first and second heat exchangers 51a and 51b. Since an external heat source is input, the self-defrosting in the other heat exchanger can be forcibly performed in a short time to prevent freezing, and heat exchange in the other heat exchanger can be prevented. It is efficiently performed from beginning to end, and solvent recovery can be performed more efficiently.

  The first and second heat exchangers 51a and 51b are housed in a common tank 73. The tank 73 also serves as a solvent liquid recovery tank. A partition wall 74 is provided between the second heat exchanger 51b and the heat exchange action in each heat exchanger is prevented from interfering with each other. Therefore, the solvent recovery device 40c is configured in a compact manner. Thus, the manufacturing cost can be reduced, and the heat exchange between the two heat exchangers can be performed efficiently.

  Moreover, since the 1st and 2nd heat exchangers 51a and 51b are comprised by the finned tubular heat exchanger, the finned tubular heat exchanger excellent in heat exchanging performance is used, And the structure which is hard to freeze of the 2nd heat exchangers 51a and 51b can be obtained, and, thereby, solvent recovery can be performed more efficiently.

Next, a fifth embodiment (embodiment 5) of the present invention will be described.
FIG. 9 is a schematic schematic configuration diagram of a solvent recovery device provided in the solvent cleaning device of the fifth embodiment. The solvent recovery device 40d included in the solvent cleaning device of the fifth embodiment basically corresponds to a solvent recovery device that is a combination of the solvent recovery devices 40b and 40c included in the solvent cleaning device of the third and fourth embodiments. That is, the solvent recovery device 40d uses the high-temperature refrigerant gas exiting the compressor 62 of the refrigerator 60, used in the solvent recovery device 40b as an external heat source of the other heat exchanger that continues its thawing operation, The heat sources used in the solvent recovery apparatus 40c and generated by the first or second heaters 52a and 52b included in the respective heat exchangers are used together. Other structural portions are not particularly different from the corresponding portions of the solvent recovery apparatuses 40b and 40c.

  In FIG. 9, the relationship between the solvent recovery device 40d and the solvent recovery devices 40b and 40c is slightly difficult to read. However, the expansion valves 64a and 64b are combined on one valve figure. The other portions are basically the same as the corresponding portions of the solvent recovery apparatuses 40b and 40c. The first and second heat exchangers 51a and 51b are constituted by finned tube heat exchangers and are housed in one common tank 73. The tank 73 also serves as a solvent liquid recovery tank. This is the same as the solvent recovery device 40c of Example 4. Therefore, further detailed description is omitted. Note that the solvent liquid recovered in the tank 73 may be directly guided to the water separator 24.

Since the solvent cleaning apparatus provided with the solvent recovery apparatus 40d of the fifth embodiment is configured as described above, the following specific effects can be obtained.
The self-defrosting operation in the other heat exchanger of the first and second heat exchangers 51a and 51b, as its heat source, the high-temperature refrigerant gas exiting the compressor 62 of the refrigerator 60, and the other Since the external heat source generated by the other external heater 52a or 52b provided in the heat exchanger is turned on, the thawing of the other heat exchanger is further compulsorily performed in a shorter time, and the ice is frozen. Even if the solvent recovery is performed continuously for a very long time, the heat exchange in the other heat exchanger is performed efficiently from start to finish. It can be carried out.

  The invention of the present application is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention.

It is a schematic block diagram of the part except the said solvent collection | recovery apparatus part of the solvent washing | cleaning apparatus provided with the solvent collection | recovery apparatus of 1st Example (Example 1) of invention of this application. It is a figure which shows the modification of the sealed complete drying tank with which the same solvent washing | cleaning apparatus is further provided. It is a figure which shows the other modification of the same sealing type complete drying tank. It is a general schematic block diagram of the solvent collection | recovery apparatus common to the solvent washing | cleaning apparatus of each Example of invention of this application. It is a typical schematic block diagram of the solvent collection | recovery apparatus with which the solvent cleaning apparatus of the present Example 1 is provided. It is a typical schematic block diagram of the solvent collection | recovery apparatus with which the solvent cleaning apparatus of 2nd Example (Example 2) of invention of this application is provided. It is a typical schematic block diagram of the solvent collection | recovery apparatus with which the solvent cleaning apparatus of 3rd Example (Example 3) of invention of this application is provided. It is a typical schematic block diagram of the solvent collection | recovery apparatus with which the solvent cleaning apparatus of 4th Example (Example 4) of invention of this application is provided. It is a typical schematic block diagram of the solvent collection | recovery apparatus with which the solvent cleaning apparatus of 5th Example (Example 5) of invention of this application is provided. It is a figure which shows the general structure of the conventional solvent washer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Corresponding part for conventional solvent washer, 11-13 ... 1st to 3rd stage washing tank, 20 ... Vapor tank (steam drying tank), 21 ... Heater, 22 ... Cooler, 23 ... Soot, 24 ... Water Separator, 25 ... Ultrasonic oscillator, 26 ... Spear, 27 ... Hanger, 30 ... Sealed complete drying tank, 31 ... Shutter, 32 ... Heater, 33 ... Gas stirring fan, 34a ... Gas suction port, 34b ... Gas discharge port 35 ... Blower fan, 36 ... Heater, 37 ... Filter, 38 ... Lid, 39 ... Piping, 40 ... Solvent recovery device, 41 ... Piping, 42 ... Precooler, 43 ... Compressor, 44 ... Piping, 50 ... Heat Exchanger unit, 51a ... first heat exchanger, 51b ... second heat exchanger, 52a ... first heater, 52b ... second heater, 53 ... piping, 54 ... separation tank (recovery tank), 55 ... Piping, 60 ... Refrigerator, 61 ... Refrigerant piping, 61 61b ... Branch refrigerant piping, 62 ... Compressor, 63 ... Condenser, 64a, 64b ... Expansion valve, 65a, 65b ... Switching valve, 66 ... Three-way valve, 67a ... High-temperature refrigerant gas piping (outward), 67b ... High-temperature refrigerant Gas piping (return path), 68a, 68b ... switching valve, 69a, 69b ... switching valve, 70 ... accumulator, 71 ... receiver tank, 72 ... piping, 73 ... tank, 74 ... partition wall, 75 ... pressure reducing valve, W ... work .

Claims (12)

In order to dry the workpiece while washing the workpiece with a solvent to remove oil and particles adhering to the workpiece,
A plurality of cleaning tanks for cleaning the workpiece by immersing it in a solvent solution;
A solvent cleaning apparatus comprising a vapor drying tank for cleaning and drying the workpiece that has exited the final stage cleaning tank among the plurality of cleaning tanks with a solvent vapor,
A closed-type complete drying tank for completely drying the work exiting the steam drying tank in a sealed room;
A solvent cleaning apparatus equipped with a solvent recovery device, further comprising a solvent recovery device that sucks, liquefies, and recovers the solvent vapor generated in the sealed complete drying tank and having an increased gas concentration . The sealed complete drying tank includes a heater for heating and drying the workpiece inside, and a gas stirring fan,
2. The solvent cleaning apparatus according to claim 1, wherein the solvent vapor generated in the closed complete drying tank is stirred by the gas stirring fan and diffused in the tank. apparatus. The sealed complete drying tank includes a closed circuit that is in fluid communication with the inside through a gas suction port and a gas discharge port,
The closed circuit is provided with a blower fan, a heater, and a filter,
Solvent vapor sucked by the blower fan from the gas suction port is heated by the heater, filtered by the filter, and discharged from the gas discharge port into the sealed complete drying tank. A solvent cleaning apparatus comprising the solvent recovery apparatus according to claim 1. The solvent recovery device is
A precooler that sucks and precools the solvent vapor having an increased gas concentration generated in the sealed complete drying tank;
A compressor that sucks and compresses the solvent vapor exiting the precooler;
First and second heat exchangers that cool and liquefy the pressurized solvent vapor exiting the compressor;
A recovery tank for recovering the solvent liquid exiting the first and second heat exchangers;
A refrigerator that supplies refrigerant gas alternately or simultaneously to at least the first and second heat exchangers,
The first and second heat exchangers are connected in series with the solvent vapor flow so that they are alternately switched between an upstream position and a downstream position of the series connection. In synchronism with the switching of the position, while the one heat exchanger located downstream of the series connection cools the pressurized solvent vapor and continues the cooling operation to liquefy, the series The other heat exchanger located on the upstream side of the connection is alternately switched so that the cooling operation is interrupted and the thawing operation for defrosting itself is continued. A solvent cleaning apparatus comprising the solvent recovery apparatus according to any one of the above. The one heat exchanger is supplied with refrigerant gas exiting the refrigerator,
5. The solvent cleaning apparatus having a solvent recovery apparatus according to claim 4, wherein an input of an external heat source is blocked in the other heat exchanger. The first and second heat exchangers include first and second external heaters, respectively.
The one heat exchanger is supplied with refrigerant gas exiting the refrigerator,
The other heat exchanger is charged with an external heat source generated by the other external heater provided in the other heat exchanger,
The external heat source generated by the other external heater supports the defrosting operation of the other heat exchanger while the other heat exchanger interrupts the cooling operation and continues the defrosting operation to defrost itself. The solvent cleaning apparatus provided with the solvent collection | recovery apparatus of Claim 4 characterized by the above-mentioned. The solvent recovery device is
A precooler that sucks and precools the solvent vapor having an increased gas concentration generated in the sealed complete drying tank;
A compressor that sucks and compresses the solvent vapor exiting the precooler;
First and second heat exchangers that cool and liquefy the pressurized solvent vapor exiting the compressor;
A recovery tank for recovering the solvent liquid exiting the first and second heat exchangers;
A refrigerator that supplies refrigerant gas alternately or simultaneously to at least the first and second heat exchangers,
The first and second heat exchangers are connected in parallel to the flow of the solvent vapor, and one of the heat exchangers continues the cooling operation for cooling and liquefying the pressurized solvent vapor. During the operation, the other heat exchanger is alternately switched to continue the thawing operation by interrupting the cooling operation and continuing the defrosting operation in a state where the heat exchanger is disconnected from the flow of the solvent vapor. A solvent cleaning apparatus comprising the solvent recovery apparatus according to any one of claims 1 to 3. The one heat exchanger is supplied with cryogenic refrigerant gas exiting the expansion valve of the refrigerator,
8. The solvent cleaning apparatus having a solvent recovery apparatus according to claim 7, wherein the other heat exchanger is supplied with a high-temperature refrigerant gas exiting the compressor of the refrigerator. . The first and second heat exchangers include first and second external heaters, respectively.
The one heat exchanger that continues the cooling operation is supplied with the refrigerant gas exiting the refrigerator,
The external heat source generated by the other external heater provided in the other heat exchanger is input to the other heat exchanger that interrupts the cooling operation. A solvent cleaning apparatus comprising the solvent recovery apparatus described. The first and second heat exchangers include first and second external heaters, respectively.
The one heat exchanger is supplied with cryogenic refrigerant gas exiting the expansion valve of the refrigerator,
The other heat exchanger is supplied with an external heat source generated by the other external heater provided in the other heat exchanger while being supplied with the high-temperature refrigerant gas exiting the compressor of the refrigerator. The external heat source generated by the other external heater supports the defrosting operation of the other heat exchanger, while the other heat exchanger interrupts the cooling operation and continues the defrosting operation of defrosting itself. The solvent cleaning apparatus provided with the solvent collection | recovery apparatus of Claim 7 characterized by the above-mentioned. The first and second heat exchangers are housed in one common tank;
The tank also serves as the recovery tank,
A partition wall is provided between the first heat exchanger and the second heat exchanger so that heat exchange actions in the heat exchangers do not interfere with each other. A solvent cleaning apparatus comprising the solvent recovery apparatus according to claim 9. 12. The solvent cleaning apparatus equipped with the solvent recovery apparatus according to claim 9, wherein the first and second heat exchangers are constituted by finned tube heat exchangers.

Images