JP2011058081A - Electrodeposition coating equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide electrodeposition coating equipment where secondary sagging upon coating film baking treatment is effectively prevented while effectively reducing the consumption energy of the equipment. <P>SOLUTION: In the electrodeposition coating equipment provided with: a baking-drying furnace 6 subjecting a coating film formed in an electrodeposition tank 2 to baking treatment; and a cooling zone 8 cooling the object to be coated B subjected to the baking treatment in the baking-drying furnace 6, as a heat radiation source, air Ay for preheating fed to a preheating furnace 5 provided between the electrodeposition tank 2 and the baking-drying furnace 6 or cleaning water W used in water-cleaning devices 3a to 3c cleaning the object to be coated B formed with a coating film in the electrodeposition tank 2 or air At for regulation fed to a conveying route part 4 between the water washing devices 3a to 3c and the preheating furnace 5 is used, also, a heat pump 9 with air Ac for cooling fed to the cooling zone 8 as a heat absorption source is provided, and, the air Ay for preheating or cleaning water or the air At for regulation is heated by the heat pump 9, and further, the air Ac for cooling is cooled. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention includes an electrodeposition bath for immersing an object to be coated in an electrodeposition coating liquid in the tank, a baking drying furnace for baking the coating film formed on the surface of the object to be coated in the electrodeposition tank, and this baking drying. This invention relates to an electrodeposition coating equipment that transports and coats coatings in sequence to a cooling zone that cools the coatings that have been baked in a furnace. In particular, it prevents so-called secondary sag in a baking and drying furnace. It is related with the electrodeposition coating equipment suitable for.

  In this type of electrodeposition coating equipment, the remaining coating liquid that has entered the gaps in the electrodeposition tank in the electrodeposition tank boiled from the gaps due to high-temperature heating in the baking and drying furnace, resulting in so-called secondary sagging, resulting in a decrease in coating quality. In order to prevent the coating film from being deposited on the surface of the object to be coated in the electrodeposition tank, a preheating furnace is provided to preheat the object to be coated with preheating air before baking in the baking and drying furnace. There is one in which the above-mentioned secondary sag is prevented by pre-drying the remaining coating liquid in the gap by low-temperature heating. (See Patent Document 1)

  In addition, a cooling zone is provided to cool the coating object after it has been baked in the baking / drying oven (coating object that is still in a high temperature state) with cooling air. In general, it is common practice to achieve thermal protection of devices and the like.

  Conventionally, in these electrodeposition coating facilities, a preheater air to be supplied to the preheating furnace is heated by a burner, an electric heater, a steam heater, or the like. In the case of supplying to the air, a cooling water coil for cooling the cooling air with the generated cold water by the refrigerator is used for cooling the cooling air.

JP-A-11-131292

  However, in the conventional electrodeposition coating equipment as described above, in addition to requiring high energy for high-temperature heating in the baking and drying furnace, large energy (that is, large fuel consumption) is required for heating the preheating air supplied to the preheating furnace. Power consumption or steam consumption), and cooling air supplied to the cooling zone also requires considerable energy (ie, large power consumption of the refrigerator). There is a problem that running costs increase, and there is room for improvement in terms of energy saving and environmental problems.

  In view of this situation, the main problem of the present invention is to adopt the rational heating and cooling method to effectively prevent the secondary sag while solving the above problem effectively.

The first characteristic configuration of the present invention relates to an electrodeposition coating facility,
An electrodeposition bath in which the object to be coated is immersed in the electrodeposition coating liquid in the tank, a baking drying furnace for baking the coating film formed on the surface of the object to be coated in this electrodeposition tank, and a coating film in this baking drying furnace In the electrodeposition coating equipment that transports and coats the coatings sequentially to the cooling zone that cools the coatings that have been baked.
Preheating air to be supplied to a preheating furnace provided between the electrodeposition tank and the baking / drying furnace, or washing water used in a water washing apparatus for washing an object to be coated formed in the electrodeposition tank, or In addition, a heat pump is provided in which the adjustment air supplied to the conveyance path portion between the water washing apparatus and the preheating furnace is used as a heat radiation source, and the cooling air supplied to the cooling zone is used as the heat absorption source.
The heat pump heats the preheating air, the cleaning water, or the adjustment air, and is configured to cool the cooling air in parallel therewith.

  That is, in this configuration, the preheating air supplied to the preheating furnace, the cleaning water used in the water washing apparatus or the adjustment air supplied to the transfer path portion is used as a heat radiation source, and the cooling air supplied to the cooling zone is used. By operating the heat pump as the heat absorption source, the preheating air, the washing water or the adjustment air as the heat radiation source is heated, and at the same time, the cooling air as the heat absorption source is cooled.

  In other words, the preheating air, the washing water, or the adjustment air is heated by using the temperature rising heat that is released as the refrigerant condensing heat as the heat pump cools the cooling air by absorbing heat due to refrigerant evaporation.

  Therefore, the preheating air, cleaning water or conditioning air is heated by a dedicated heating device such as a burner, an electric heater or a steam heater, and separately cooled by a cooling dedicated means such as a cold water coil using a refrigerator generated cold water. Compared to cooling the working air, both heating and cooling can be performed only by the operating power of the heat pump, and the energy consumption of the entire facility can be effectively reduced.

  And if the structure which heats the preheating air supplied to the said preheating furnace or the adjustment air supplied to the said conveyance path part is taken, the residual coating material in the clearance gap part in a to-be-coated article with these heated preheating air or adjustment air The liquid can be pre-dried to prevent the above-mentioned secondary sag, and if the washing water used in the washing apparatus is heated, the remaining paint in the gaps in the object to be coated can be washed by the heated washing water. The liquid can be effectively removed at the cleaning stage following the electrodeposition tank to prevent the above-mentioned secondary sag.

  On the other hand, by cooling the cooling air supplied to the cooling zone, the coated object is heated at a higher temperature after the coating film baking process in the baking / drying furnace, compared to cooling the coated object in the cooling zone by ventilation of room temperature outside air. The coating can be efficiently and effectively cooled for the purpose of facilitating subsequent operations and thermal protection of the devices.

  For these reasons, according to the first feature configuration described above, secondary sag can be effectively prevented while reducing energy consumption as a whole facility and making the facility excellent in terms of energy saving and environmental problems. In addition to ensuring high coating quality, it is also possible to effectively achieve smoothing of subsequent operations following the coating baking process and thermal protection of the devices.

  In addition, in implementation of this structure, it is restricted to the structure which heats only any one among the preheating air supplied to a preheating furnace or the adjustment air supplied to the washing water used with a water-washing apparatus, or a conveyance path part. Instead, two or more of them may be simultaneously or selectively heated by a heat pump.

  In order to heat these preheating air, washing water or conditioning air, the preheating air, washing water or conditioning air is heated (preheated) by a heat pump and then heated by another heating means, or vice versa. In addition, after preheating the preheating air, the washing water, or the adjusting air by another preheating means, a configuration in which the air is further heated by a heat pump may be adopted.

  On the other hand, to cool the cooling air, the cooling air is cooled by a heat pump (precooled) and then cooled by another cooling means, or conversely, the cooling air is precooled by another precooling means Further, a configuration in which cooling is performed by a heat pump may be adopted.

  In addition, if the heating amount for preheating air, washing water or conditioning air and the temperature after heating, and the cooling amount for cooling air and the temperature after cooling can be adjusted, the functionality and operating conditions can be adjusted. The equipment can be made more excellent in adaptability to changes.

  The heat pump to be used is not limited to the vapor compression heat pump, and various types of heat pumps such as an absorption heat pump can be adopted.

The second feature configuration of the present invention specifies an embodiment suitable for the implementation of the first feature configuration.
A pre-cooling zone is provided between the baking / drying furnace and the cooling zone for cooling the coating object, which has been baked by the baking / drying furnace, with outside air.

  In other words, according to this configuration, after pre-cooling with the ventilated outside air in the pre-cooling zone and subsequent cooling with cooling air (air cooled by the heat pump) in the cooling zone, after the coating film baking process in the baking and drying furnace Since the high-temperature coated object is cooled, the high-temperature coated object after the coating film baking process can be cooled more efficiently and effectively. Thermal protection can be achieved more effectively.

  Moreover, since the removal of the coating material from the baking and drying furnace is accompanied by an exhaust gas containing a spear component generated in the coating film baking process, the coated material after the coating film baking process is immediately cooled in the cooling zone. In the case of cooling with the cooling air, the spear component in the accompanying exhaust gas may be condensed in the cooling zone and adhere to the zone wall or the object to be coated. With the accompanying exhaust gas contained in the pre-cooling zone removed by ventilated outside air, the object to be coated can be cooled with low-temperature cooling air in the cooling zone following the pre-cooling in the pre-cooling zone. The maintenance work for removing the components can be effectively reduced, and the deterioration of the coating quality due to the adhesion of the spear component to the object to be coated can be effectively prevented.

  In the implementation of this configuration, the article to be coated after the coating film baking process is performed by only one of pre-cooling by the ventilating outside air in the pre-cooling zone and cooling by the cooling air in the cooling zone in accordance with changes in operating conditions. Operation mode for cooling the air, cooling air supplied to the cooling zone together with the cooling air supplied to the pre-cooling zone, operating mode for cooling the coating object by the outside air in both the pre-cooling zone and the cooling zone, etc. If the configuration can be switched appropriately, it is possible to further improve the functionality and the adaptability to changes in operating conditions.

The third feature configuration of the present invention specifies an embodiment suitable for the implementation of the first or second feature configuration.
As the cooling air is supplied to the cooling zone, the air in the cooling zone is discharged to the outside, and an exhaust mixing means for mixing a part of the discharged air with the cooling air is provided,
This exhaust gas mixing means is configured such that the mixing ratio of the cooling air and the exhaust air mixed therewith can be adjusted.

  In other words, according to this configuration, by adjusting the mixing ratio between the cooling air and the exhaust air mixed therewith (that is, the air heated by cooling the coating object in the cooling zone), the cooling air before cooling is adjusted. The temperature of the cooling air supplied to the cooling zone can be adjusted according to operating conditions such as the temperature of the air and the coating film thickness of the object to be coated.

  Also, with this configuration, the temperature of the cooling air is adjusted by adjusting the mixing ratio, so that adjustment of the heat pump output is limited due to heating of preheating air, washing water, or adjustment air. However, it is possible to adjust the temperature of the cooling air supplied to the cooling zone, and in this respect, it is possible to make the equipment more excellent in response to changes in functionality and operating conditions.

  In the implementation of this configuration, the cooling air for mixing a part of the exhaust air may be either the cooling air after cooling or the cooling air before cooling.

The fourth characteristic configuration of the present invention specifies an embodiment suitable for the implementation of any of the first to third characteristic configurations,
The preheating air or the cleaning water or the adjustment air is heated by the retained heat of the exhaust gas discharged from the baking drying furnace and the heat released from the heat pump.

  That is, according to this configuration, not only the heat released from the heat pump (refrigerant condensation heat) but also the retained heat of the exhaust gas discharged from the baking / drying furnace (in other words, the heat recovered from the exhaust gas) is used for preheating air. Or, since the washing water or the adjustment air is heated, the heating capacity for the preheating air, the washing water or the adjustment air can be secured while reducing the required capacity of the heat pump. The above-mentioned secondary sagging prevention by heating preheating air, washing water or conditioning air can be effectively achieved while further reducing the energy consumption and reducing the size of the heat pump to be used. it can.

  In the implementation of this configuration, the preheating air or the cleaning water or the conditioning air is heated (preheating) by the heat released from the heat pump and then heated by the retained heat of the exhaust gas, or conversely, the preheating air or the cleaning water Alternatively, the preconditioning air is preheated by the retained heat of the exhaust gas and then heated by the heat released from the heat pump, or alternatively, the preheating air, the washing water or the adjusting air is heated by the mixed heat of the heat pump discharged heat and the exhaust gas retained heat. Any of the configurations may be adopted, and the heating mode may be switched appropriately.

  In addition, if the heating amount of preheating air or washing water or adjustment air by heat released from the heat pump or the heating amount of preheating air or washing water or adjustment air by exhaust gas holding heat can be adjusted, functionality and operating conditions can be adjusted. It is possible to make the equipment more excellent in response to the change in the temperature.

The fifth characteristic configuration of the present invention specifies an embodiment suitable for implementation of any of the first to fourth characteristic configurations,
A heat-dissipation-side heat medium liquid circulation path is provided that circulates a heat-dissipation-side heat medium liquid between a heater that heats the preheating air, the washing water, or the adjustment air and a heat radiator as a refrigerant condenser in the heat pump. With
The heat absorption side heat medium liquid circulation path which circulates the heat absorption side heat medium liquid between the cooler which cools the said cooling air, and the heat absorber as a refrigerant evaporator in the said heat pump is provided.

  In other words, the heating medium liquid circulation type in which the heat-dissipating side and the heat-absorbing-side heat medium liquid circulation path as described above is provided to heat the preheating air, the washing water or the adjustment air by the heat pump and to cool the cooling air Instead of direct heating, the preheating air or the washing water or the conditioning air is directly heated by a radiator as a refrigerant condenser in the heat pump, and the cooling air is directly supplied by a heat absorber as a refrigerant evaporator in the heat pump. It is also possible to adopt a direct cooling type (so-called direct expansion type) in which the cooling is performed.

  However, in these direct heating systems and direct cooling systems, the heating efficiency and cooling efficiency of the heat pump (that is, the coefficient of performance of the heat pump) decrease as the length of the refrigerant pipe for the refrigerant condenser and the refrigerant evaporator increases.

  On the other hand, according to the above configuration, the refrigerant pipe and the refrigerant evaporator are fixed to a short length of refrigerant pipe (in short, a state in which the heat pump is unitized including the refrigerant condenser and the refrigerant evaporator). ), The extension path of the heat transfer medium circulation path on the heat radiation side and the heat absorption side is appropriately determined, and the installation position of the heater for the preheating air, the washing water or the adjustment air, and the cooling position for the cooling air is appropriately determined. Accordingly, compared to the direct heating method and the direct cooling method, it is possible to secure high heating design and cooling efficiency of the heat pump with a high degree of freedom in equipment design while stably ensuring high heating efficiency and cooling efficiency.

  In the implementation of this configuration, a part of the heat medium liquid sent from the heat pump side (that is, the heat medium liquid heated or cooled by the heat pump) is short-circuited to the heat medium liquid circulation path on the heat radiating side or the heat absorbing side. A valve device that can be recirculated to the side and that can adjust the short-circuit recirculation amount is provided. By adjusting the short-circuit recirculation amount by this valve device, the heating amount of the preheating air, the washing water or the adjustment air, or the cooling air It is desirable to be able to adjust the amount appropriately.

  If water is used as the heat transfer fluid to be circulated in the heat dissipation liquid and heat absorption heat transfer circuits, the equipment cost can be reduced and the equipment management can be facilitated, but the heat transfer liquid is limited to water. Instead, various liquids such as an aqueous solution such as brine or a liquid agent not containing water can be employed.

Overall side view of electrodeposition coating equipment Enlarged side view showing parts of preheating furnace and baking drying furnace Enlarged side view showing pre-cooling zone and cooling zone part

  FIGS. 1 and 2 show an electrodeposition coating facility, where 1 is a water-washing process, a degreasing process, a chemical conversion process, a water-washing process, etc., on an object B (automobile body in this example) transported by a transporting device Ca. A pretreatment unit 2 for sequentially performing the treatment is an electrodeposition tank 2 in which the pre-treated article B is immersed in the electrodeposition coating liquid L in the tank along with the subsequent conveyance by the conveyance device Ca. In No. 2, an in-liquid coating component of the electrodeposition coating liquid L is applied to the coating B by electrophoresis between the immersion electrode plate and the immersion coating B serving as the counter electrode, and the coating is applied to the surface of the coating. Form.

  Reference numeral 3 denotes an electrodeposition water washing section for washing the coating object B after the formation of the coating film pulled up from the electrodeposition coating liquid L in the electrodeposition tank 2 from the washing water W along with the conveyance by the conveying device Ca. The part 3 is coated with a pre-stage water washing part 3A for washing the article to be coated B with the purified washing water W by an ultrafiltration membrane or the like, and subsequently using the purified washing water or pure water by the reverse osmosis membrane as the washing water W. A latter-stage water washing section 3B for washing the product B is provided.

  Reference numeral 4 denotes a transfer route portion for relaying the object B washed by the subsequent water washing section 3B to the preheating furnace 5, and the object B is conveyed in the furnace from the previous conveying device Ca to the transfer route portion 4. The transfer apparatus I which transfers to the transfer apparatus Cb for use is provided.

  The preheating furnace 5 includes a heater 5a that heats the preheating air Ay supplied to the preheating furnace 5, a circulation path 5c that circulates the preheating air Ay between the heater 5a and the preheating furnace 5 by a circulation fan 5b, An air supply chamber 5d having a ceiling portion for supplying preheating air Ay heated by the heater 5a into the preheating furnace 5 from a number of nozzles, and a floor portion for sucking in-furnace air Ay 'to be returned to the heater 5a from a number of suction ports. An exhaust chamber 5e is provided.

  That is, by preheating the coating object B to about 60 ° C. to 100 ° C. with the preheating air Ay in the preheating furnace 5, it remains in the gap portion of the coating object B even after the water washing in the electrodeposition washing unit 3. The electrodeposition coating liquid L is pre-dried to prevent secondary sag in the subsequent baking / drying furnace 6.

  Reference numeral 6 denotes a baking / drying furnace in which the object B preheated in the preheating furnace 5 is heated at a high temperature to bake the formed coating film on the surface of the object to be coated. A combustion type heater 6a for dividing the zone air Az to about 170 ° C. is provided for each of the processing zones 6z.

  Specifically, the circulation path 6c circulates the in-zone air Az by the circulation fan 6b between the heater 6a and the processing zone 6z, and the air Ak heated by the heater 6a is supplied into the processing zone 6z from a number of nozzles. The floor-side air supply chamber 6d and the ceiling-side exhaust chamber 6e for sucking in-zone air Az returned to the heater 6a from a large number of suction ports are provided for each processing zone 6z.

  An outside air introduction path 6f is connected to the upper portion of the heater 6a in the circulation path 6c of each processing zone 6z, and the introduced outside air Ao from the outside air introduction path 6f and the in-zone air Az sucked into the exhaust chamber 6e The air-fuel mixture is heated by the heater 6a, and this heated air Ak is supplied as processing zone heating air from the supply chamber 6d into the processing zone 6z.

  Further, an exhaust port 6g for discharging the furnace air Ag corresponding to the amount of outside air introduced from the outside air introduction path 6f is provided at the center of the baking / drying furnace 6 in the direction in which the object is conveyed. Air Ag (that is, exhaust gas containing a spear component) is guided to the catalytic oxidizer 6j through the exhaust gas air passage 6i by the exhaust gas fan 6h to be purified and deodorized.

6k is a preheater that preheats the introduced outside air Ao by heat-exchanging the treated high-temperature exhaust gas Ag of about 230 ° C. that has been purified and deodorized by the catalytic oxidizer 6j and the introduced outside air Ao in the outside air introduction path 6f. The treated exhaust gas Ag used for preheating the introduced outside air Ao at 6k is discharged outdoors.
7 is a pre-cooling zone for pre-cooling the high-temperature coating B after the coating film baking process carried out from the baking / drying furnace 6 by the transport device Cb, and 8 is a pre-cooling zone 7 for the coating B to be transported by the transport device Cb. This is a cooling zone for subsequent cooling. The pre-cooling zone 7 has a ceiling-side air supply chamber for supplying room temperature outside air Ao introduced by the air supply fan 7b through the outside air introduction path 7a into the pre-cooling zone 7 from a number of nozzles. 7c and a floor-arranged exhaust chamber 7f for sucking in-zone air Ao 'discharged to the outside by an exhaust fan 7e through an exhaust passage 7d from a plurality of suction ports.

  On the other hand, in the cooling zone 8, a cooler 8 g that cools the room temperature outside air Ao introduced by the air supply fan 8 b through the outside air introduction path 8 a, and the outside air cooled by the cooler 8 g as cooling air Ac from a number of nozzles. An air supply chamber 8c having a ceiling portion disposed in the cooling zone 8 and an exhaust chamber 8f having a floor portion for sucking in-zone air Ac 'discharged to the outside by an exhaust fan 8e through an exhaust passage 8d from a plurality of suction ports. It is provided.

  That is, in the pre-cooling zone 7, the high-temperature coating B after the coating baking process is pre-cooled by the ambient air Ao at room temperature, and in the cooling zone 8, the pre-cooled coating B is cooled by the cooler 8 g. It is made to cool with the working air Ac, and thereby, the high-temperature article B after the coating film baking process is efficiently and effectively cooled to about room temperature and sent to the subsequent process.

  In addition, the exhaust gas Ag containing spider component accompanying the material B to be carried out from the baking / drying furnace 6 is removed by the ventilated outside air Ao in the precooling zone 7, whereby the spider component in the accompanying exhaust gas Ag is condensed in the cooling zone 8. Thus, it can be surely prevented from adhering to the wall of the cooling zone 8 and the object B to be coated.

  Note that a filter fi for purifying the air to be treated is provided in each of the heater 5a of the preheating furnace 5, the heater 6a of the baking and drying furnace 6, the cooler 8g of the cooling zone 8, and the outside air introduction path 7a of the precooling zone 7. Is equipped.

  Regarding the heating of the preheating air Ay by the heater 5a in the preheating furnace 5 and the cooling of the cooling air Ac by the cooler 8g in the cooling zone 8, carbon dioxide as a refrigerant is converted into a compressor 9a and a condenser 9b ( A unitized supercritical heat pump 9 that circulates in the order of a radiator), an expansion valve 9c, and an evaporator 9 (heat absorber), and the radiator 9b of the heat pump 9 is used as the heat transfer means 10 on the radiation side. Between the (condenser) and the heater 5a of the preheating furnace 5, a heat-dissipation-side heat medium liquid circulation path 10b for circulating the heat-dissipation-side heat medium liquid Wh (water in this example) by the circulation pump 10a is provided.

  Further, as the heat transfer means 11 on the heat absorption side, the heat absorption side heat transfer liquid Wc (water in this example) is transferred between the heat absorber 9d (evaporator) of the heat pump 9 and the cooler 8g of the cooling zone 8 by the circulation pump 11a. A heat transfer medium circulation path 11b on the heat absorption side to be circulated is provided.

  That is, in the heat transfer means 10 on the heat radiation side, the circulating heat medium fluid Wh is circulated in the heat radiator 9b (condenser) of the heat pump 9 by the heat released from the heat pump 9 (that is, generated condensation heat accompanying refrigerant condensation, strictly speaking, Preheated by heat exchange in the heater 5a between the heated heat transfer fluid Wh and the preheating air Ay supplied to the preheating furnace 5 The working air Ay is heated.

  Further, in parallel with the heating of the preheating air Ay by the heat pump discharge heat, in the heat transfer means 11 on the heat absorption side, the circulating heat absorption side heat transfer medium Wc is transferred to the heat pump 9 in the heat absorber 9d (evaporator). Cooling is performed by heat exchange in the cooler 8g between the cooled heat-absorbing-side heat transfer fluid Wc and the cooling air Ac supplied to the cooling zone 8 by heat absorption (that is, taking heat of vaporization accompanying refrigerant evaporation). Air Ac is cooled.

  Regarding the heating of the preheating air Ay by the heater 5a in the preheating furnace 5, the heat radiation side heat medium sent from the heat radiator 9b of the heat pump 9 to the heater 5a of the preheating furnace 5 is further transferred to the heat medium liquid circulation path 10b on the heat radiation side. A portion Wh ′ of the liquid Wh is short-circuited to the radiator 9b of the heat pump 9 through the short circuit 10c, and a three-way valve 10d for adjusting the short-circuit recirculation amount is provided, and the preheating air heated by the heater 5a A temperature sensor Sy that detects the temperature ty of the preheating air Ay that is supplied to the preheating furnace 5 is provided in the forward path portion of the circulation path 5 c that supplies Ay to the preheating furnace 5.

  For the heater that adjusts the heating amount of the heater 5a with respect to the preheating air Ay by operating the three-way valve 10d based on the detected temperature ty of the temperature sensor Sy to adjust the short-circuit reflux amount of the heat-dissipation-side heat transfer fluid Wh. A controller 12 is provided, and the temperature ty of the preheating air Ay supplied to the preheating furnace 5 is automatically adjusted to a required temperature by adjusting the heating amount by the heater controller 12.

  The heat pump 9 has a function of automatically adjusting the rotational speed of the compressor 9a so that the temperature of the heat-dissipation-side heat transfer fluid Wh sent from the radiator 9b (that is, the temperature after heating) is maintained at a predetermined temperature. Because of this function, when the short circuit recirculation amount of the heat-dissipation-side heat transfer fluid Wh is adjusted to the increase side by the heater controller 12, the rotational speed of the compressor 9a is adjusted to the decrease side accordingly, and the radiator 9b The amount of released heat (that is, the amount of heat applied to the heat-dissipation-side heat medium liquid Wh) and the amount of heat absorbed by the heat absorber 9d (that is, the amount of cooling to the heat-absorbing-side heat medium liquid Wc) are also automatically adjusted to the lower side.

  On the other hand, for cooling the cooling air Ac by the cooler 8g in the cooling zone 8, as the exhaust mixing means 13, an external air damper 13a for adjusting the amount of air introduced into the cooler 8g and the exhaust air in the exhaust passage 8d. A mixing path 13b for introducing a part of Ac ′ (that is, air heated by cooling the coating object in the cooling zone 8) to the cooler 8g, and an exhaust air flow rate to be introduced to the cooler 8g through the mixing path 13b. A mixing damper 13c to be adjusted is provided, and a temperature sensor Sc for detecting the temperature tc of the cooled cooling air Ac supplied to the cooling zone 8 is provided.

  Then, based on the detected temperature tc of the temperature sensor Sc, the outside air damper 13a and the mixing damper 13c are operated to introduce the air volume ratio between the outside air Ao introduced into the cooler 8g and the discharged air Ac '(that is, the air Ao, Ac'). The mixing controller 13d for adjusting the mixing ratio) is provided, and by adjusting the air flow ratio (mixing ratio adjustment) by the mixing controller 13d, the air volume of the cooling air Ac supplied to the cooling zone 8 is kept constant, The temperature tc of the cooling air Ac is automatically adjusted to the required temperature.

As described above, in the electrodeposition coating equipment shown in this embodiment, the electrodeposition tank 2 in which the object B is immersed in the electrodeposition coating liquid L in the tank, and the electrodeposition tank 2 are formed on the surface of the object B to be coated. The coating material B is sequentially conveyed to the baking and drying furnace 6 for baking the coated film, and the cooling zone 8 for cooling the coating material B that has been baked in the baking and drying furnace 6 for coating. In
A heat pump 9 having a preheating air Ay supplied to a preheating furnace 5 provided between the electrodeposition tank 2 and the baking / drying furnace 6 as a heat radiation source and a cooling air Ac supplied to the cooling zone 8 as a heat absorption source The heat pump 9 is configured to heat the preheating air Ay supplied to the preheating furnace 5 and to cool the cooling air Ac supplied to the cooling zone 8 in parallel therewith.

  Further, a pre-cooling zone 7 is provided between the baking / drying furnace 6 and the cooling zone 8 to cool the article B to be coated, which has been baked by the baking / drying furnace 6, with the outside air Ao.

  Further, as the cooling air Ac is supplied to the cooling zone 8, the air Ac 'in the cooling zone 8 is discharged to the outside, and an exhaust mixing means for mixing a part of the discharged air Ac' with the cooling air Ac. 13, the exhaust mixing means 13 is configured to be able to adjust the mixing ratio of the cooling air Ac and the exhaust air Ac ′ mixed therewith.

  Further, the heat-side heat medium liquid circulation that circulates the heat-side heat medium liquid Wh between the heater 5a that heats the pre-heating air Ay supplied to the pre-heating furnace 5 and the heat radiator 9d as a refrigerant condenser in the heat pump 9 is performed. While providing the path 10b, the heat absorption side heat medium liquid Wc is circulated between the cooler 8g for cooling the cooling air Ac supplied to the cooling zone 8 and the heat absorber 9d as a refrigerant evaporator in the heat pump 9. The heat medium liquid circulation path 11b is provided.

  In addition, a part Wh ′ of the heat medium fluid Wh sent from the heat pump 9 side (that is, the heat medium liquid heated by the heat pump 9) is returned to the heat pump 9 side in a short circuit to the heat medium liquid circulation path 10b on the heat radiation side. In addition, a valve device (three-way valve 10d) capable of adjusting the short-circuit recirculation amount is provided, and the heating amount of the preheating air Ay supplied to the preheating furnace 5 is appropriately adjusted by adjusting the short-circuit recirculation amount by the valve device 10d. It can be configured.

[Another embodiment]
Next, another embodiment will be listed.

  In the above-described embodiment, the preheating air Ay supplied to the preheating furnace 5 is heated by the heat released from the heat pump 9, but instead of or in addition to this, as shown by a broken line in FIG. Washing water heating for heating the washing water W used in each washing device in the electrodeposition washing unit 3, such as the washing water W (pure water) used in the submerged washing unit 3B, the shower washing unit 3b, or the final shower washing unit 3c. 14a to 14c and the heat transfer means 10 on the heat dissipation side, the heat transfer medium 10 is disposed between the wash water heaters 14a to 14c and the heat dissipator 9b of the heat pump 9. The heat-dissipation-side heat medium liquid circulation path 10b 'to be circulated may be provided.

  That is, in this configuration, the washing water Wb used in the washing apparatuses 3a to 3c of the electrodeposition washing unit 3 is heated by the heat released from the heat pump 9, and the remaining in the gaps in the coating B is washed by the heated washing water Wb. The coating liquid L is effectively removed at the cleaning stage following the electrodeposition tank 2, thereby preventing secondary sag in the coating film baking process in the baking / drying furnace 6.

  Further, in place of or in addition to heating the preheating air Ay supplied to the preheating furnace 5 and the washing water Wb used in the washing apparatuses 14a to 14c of the electrodeposition washing section 3 by the heat released from the heat pump 9, As shown by a broken line in FIG. 1, a transfer route portion 4 for relay between the electrodeposition water washing portion 3 provided with a water washing device and the preheating furnace 5 (in the above-described embodiment, the upper side portion or the lower side portion of the transfer device I). The adjustment air heater 15 for heating the adjustment air At supplied to the portion) is provided, and the heat transfer means 10 on the heat radiation side is provided between the adjustment air heater 15 and the radiator 9b of the heat pump 9. A heat-dissipation-side heat medium liquid circulation path 10b ″ for circulating the heat-dissipation-side heat medium liquid Wh by the circulation pump 10a ″ may be provided.

  That is, in this configuration, the residual coating liquid L in the gaps in the article to be coated B is pre-dried by the heated adjustment air At supplied to the conveyance path portion 4, and thereby the coating film is baked in the baking / drying furnace 6. Prevents secondary sag in processing.

  That is, in the electrodeposition coating equipment of the present invention, the preheating air Ay supplied to the preheating furnace 5 provided between the electrodeposition tank 2 and the baking / drying furnace 6 or the coating film formed in the electrodeposition tank 2 is coated. Wash water W used in the washing devices 3a to 3c for washing the object B, or the adjustment air At supplied to the transport path portion 4 between the washing devices 3a to 3c and the preheating furnace 5 as a heat radiation source, and , A heat pump 9 having a cooling air Ac supplied to the cooling zone 8 as a heat absorption source is provided. By this heat pump 9, the preheating air Ay supplied to the preheating furnace 5 or the cleaning water W or the transport used in the water washing devices 3a to 3c The adjustment air At supplied to the path portion 4 is heated, and the cooling air Ac supplied to the cooling zone 8 is cooled at the same time.

  In order to heat the preheating air Ay, the cleaning water W, or the adjustment air At and simultaneously cool the cooling air Ac, the heat transfer means 10 on the heat radiation side and the heat transfer means 11 on the heat absorption side as described above are used. The preheating air Ay, the washing water W or the adjustment air At is directly heated by the radiator 9b (condenser) of the heat pump 9, or the cooling air Ac is heated by the heat absorber 9d (evaporation) of the heat pump 9. It is also possible to employ a configuration in which the air is directly cooled by a container.

  In order to adjust the output of the heat pump 9 (ie, the amount of released heat and the amount of absorbed heat), the output of the heat pump is changed according to the temperature of the preheating air Ay, the washing water W, the adjusting air At, or the temperature of the cooling air Ac, etc. You may make it adjust by.

  The heat pump 9 is not limited to a vapor compression heat pump, and an absorption heat pump or an adsorption heat pump may be used.

  In the above-described embodiment, the preheating air Ay supplied to the preheating furnace 5, the cleaning water W used in the water washing apparatuses 3 a to 3 c or the adjustment air At supplied to the transport path portion 4 is heated only by the heat released from the heat pump 9. Instead of this, instead of this, as shown by the broken line in FIG. 1, the exhaust gas Ag after purification deodorizing treatment that has passed through the preheater 6k in the baking and drying furnace 6 and the preheater 5a in the preheater 5 are heated (preheated). The preheated air Ay or the washing water W depends on the retained heat of the exhaust gas Ag discharged from the baking / drying furnace 6 and the heat released from the heat pump 9, such as by providing a heat exchange device 16 such as a run-around type for exchanging heat with the air Ay. Alternatively, the adjustment air At may be heated.

  In this case, the preheating air Ay or the cleaning water W or the conditioning air At is preheated by the heat released from the heat pump 9 and then heated by the retained heat of the exhaust gas Ag, or conversely, the preheating air Ay or the cleaning air Any of the methods of preheating the water W or the adjustment air At with the retained heat of the exhaust gas Ag and then heating with the heat released from the heat pump 9 may be adopted.

  In the above-described embodiment, the pre-cooling zone 7 for pre-cooling the high-temperature article B subjected to the baking treatment with the baking / drying furnace 6 by the ventilation outside air Ao is provided. However, the pre-cooling zone 7 is omitted or paused, and the baking drying is performed. You may make it cool the high temperature to-be-coated object B which baked the coating film in the furnace 6 only with the cooling air Ac of the cooling zone 8. FIG.

  The electrodeposition coating equipment according to the present invention is not limited to the electrodeposition coating of the automobile body B, but can be applied to the electrodeposition coating of various objects to be coated such as casings of steel products, steel plates or various parts.

  The electrodeposition coating equipment according to the present invention can be used for electrodeposition coating of various objects in a state where secondary sagging during the coating baking process is prevented.

B Coating object L Electrodeposition coating liquid 2 Electrodeposition tank 6 Baking and drying furnace 8 Cooling zone 5 Preheating furnace Ay Preheating air 3a-3c Flushing device W Washing water 4 Conveyance path part At Adjustment air Ac Cooling air 9 Heat pump Ao Outside air Ac 'Exhaust air 13 Exhaust gas mixing means Ag Exhaust gas 5a Heater (preheating air system)
14a-14c Heater (wash water system)
15 Heater (Air system for adjustment)
9b Radiator (condenser)
8g cooler (cooling air system)
9d heat absorber (evaporator)
Wh Heat-dissipation-side heat transfer fluid Wc Heat-absorption-side heat transfer solution 10b Heat-dissipation-side heat transfer solution circulation path (preheating air system)
10b 'Heat transfer medium circulation path on the heat radiation side (wash water system)
10b "Heat transfer medium circulation path on the heat release side (air system for adjustment)
11b Heat-absorbing heat medium liquid circuit (cooling air system)

Claims (5)

An electrodeposition bath in which the object to be coated is immersed in the electrodeposition coating liquid in the tank, a baking drying furnace for baking the coating film formed on the surface of the object to be coated in this electrodeposition tank, and a coating film in this baking drying furnace An electrodeposition coating facility for sequentially transporting and painting a coating to a cooling zone for cooling the coating after baking.
Preheating air to be supplied to a preheating furnace provided between the electrodeposition tank and the baking / drying furnace, or washing water used in a water washing apparatus for washing an object to be coated formed in the electrodeposition tank, or In addition, a heat pump is provided in which the adjustment air supplied to the conveyance path portion between the water washing apparatus and the preheating furnace is used as a heat radiation source, and the cooling air supplied to the cooling zone is used as the heat absorption source.
An electrodeposition coating facility configured to heat the preheating air, the cleaning water, or the adjustment air by the heat pump and simultaneously cool the cooling air.   The electrodeposition coating equipment according to claim 1, wherein a pre-cooling zone is provided between the baking / drying furnace and the cooling zone to cool an object to be coated, which has been baked in the baking / drying furnace, with outside air. As the cooling air is supplied to the cooling zone, the air in the cooling zone is discharged to the outside, and an exhaust mixing means for mixing a part of the discharged air with the cooling air is provided,
The electrodeposition coating equipment according to claim 1 or 2, wherein the exhaust mixing means is configured to be capable of adjusting a mixing ratio of the cooling air and the exhaust air mixed therewith.   4. The structure according to claim 1, wherein the preheating air, the washing water, or the adjustment air is heated by the retained heat of the exhaust gas discharged from the baking drying furnace and the heat released from the heat pump. Electrodeposition coating equipment described in 1. A heat-dissipation-side heat medium liquid circulation path is provided that circulates a heat-dissipation-side heat medium liquid between a heater that heats the preheating air, the washing water, or the adjustment air and a heat radiator as a refrigerant condenser in the heat pump. With
The heat absorption side heat-medium liquid circulation path which circulates the heat-absorption side heat-medium liquid between the cooler which cools the said cooling air, and the heat absorber as a refrigerant evaporator in the said heat pump is provided. The electrodeposition coating equipment according to claim 1.

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