JP2001259503A - Drying furnace for coating and method for operating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems such as a large heat loss and deterioration of a coated film in finishing quality by employing a rational way on the carriage of coated materials and the change of the substantial length of a furnace. SOLUTION: The inner part of the furnace is divided into a plurality of section areas E, each of which contains one heating zone 5 or a plurality of continuous heating zones 5. Doors 7 are installed at the entrance and exit of the respective section areas E for the coated materials. These doors are opened or closed synchronously with the intermittent carriage of the coated materials by a carrying means T. Of all the section areas, the number of the section areas E to operate for drying treatment is changed in a series of section areas E in the direction of carrying the coated material as an objective section areas E for operation in the case of operation of a plurality of the section areas E in correspondence to the change in the scheduled number of coated materials to be treated per unit time. The time for drying the coated films of the coated respective material in the furnace is adjusted to a appropriate time by changing a set tact time of the carrying means T corresponding to the change in the number of the areas for the operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of transporting a plurality of objects to be treated in a furnace in a row arranged in the direction of conveyance in a furnace by a conveying means, and drying the coating film of each of the objects during the passage through the furnace. The present invention relates to a paint drying furnace to be treated and an operation method thereof.

[0002]

2. Description of the Related Art Conventionally, in this type of coating and drying furnace, the number of coated articles processed per unit time (ie, the number of processed coated articles unloaded from the furnace per unit time) is changed. In the change to the reduction side of the number of treatments, the conveying speed of the coating material is slowed down, and, along with this, the heating device of the heating zone on the downstream side of the plurality of heating zones arranged in the conveying direction in the furnace is stopped, Substantially shorten the length of the paint drying oven,
In this way, a method has been proposed in which the number of coated articles processed per unit time is reduced while avoiding excessive baking (see, for example, JP-A-6-246219).

[0003]

However, in the above-mentioned conventional method, the number of coated articles processed per unit time is basically changed simply by increasing or decreasing the transport speed. In order to allow the coating material to move (move) without hindrance, it is not possible to provide a door for preventing hot air leakage at the entrance of the furnace or at a location that will be a substantial exit due to a substantial change in the furnace length. Even if provided, the ratio of opening time of those doors will be large, so the hot air leakage from the furnace will be large and the heat loss will be large, and the cold air flowing into the furnace due to the hot air leakage will also be large. Thus, there was a problem that the finished quality of the coating film was deteriorated.

On the other hand, there has been proposed a method in which an air curtain is formed at a furnace inlet or a substantial furnace outlet in place of a door. The effect of suppressing the inflow of cold air is low, and the same problem also occurs. On the contrary, the low-temperature airflow that forms the air curtain promotes heat loss and deterioration of coating film quality.

[0005] In particular, these problems tend to become relatively remarkable as the ratio of the amount of hot air leakage or the amount of cold air inflow to the substantial volume of the furnace increases as the substantial furnace length becomes shorter. Therefore, when the transport speed is reduced to reduce the number of coated articles processed per unit time, the rate of reduction in energy consumption is low, even though the heating device in the subsequent heating zone is stopped. Disadvantaged in terms of
In addition, there was a problem that the quality deterioration of the coating film caused by the inflow of cold air became more conspicuous.

In view of this situation, the main problems of the present invention are:
The present invention is to solve the above problems effectively by adopting a rational format for the transfer of the coating material and the change of the substantial furnace length.

[0007]

Means for Solving the Problems [1] In the invention according to claim 1, a plurality of coating objects to be processed are transferred in a furnace by a transfer means in a row arranged in the transfer direction, and the process of passing through the furnace is performed. With respect to a coating drying furnace for drying the coating film of each coated material, the conveying means is sent at a set tact time in a form in which each coated material is sequentially stopped in a plurality of heating zones arranged in the conveying direction in the furnace. It is configured to operate so as to intermittently transport the coating material row, and to partition the inside of the furnace into a plurality of partition areas including one heating zone or a plurality of continuous heating zones in one partition area. A door is provided for opening and closing the entrance and exit of the painted object in each of the divided areas, and the transport means is configured to be capable of changing the set tact time. Individual Stop to is configurable.

In other words, in this configuration, the coated article row is intermittently conveyed in a form in which each coated article is sequentially stopped in a plurality of heating zones arranged in the furnace. In the intermittent conveyance, the coated article stops in each heating zone. In this mode, the door is opened and closed in synchronization with the intermittent transport of the painted object so that the door is opened when the painted object is moved so that each painted object can pass through without interruption. However, a large closing time ratio of the door can be secured, thereby effectively preventing hot air leakage from the furnace and accompanying cold air inflow into the furnace, resulting in heat loss due to hot air leakage and cold air inflow. This can effectively prevent the quality of the finished coating film from deteriorating.

[0009] Regarding the change in the number of coated articles processed per unit time (so-called production amount adjustment), the individual operation of the above-mentioned divided areas is stopped to change the number of the divided areas in which the drying operation is performed. In addition, in the case of performing the operation in a plurality of section areas for the change, by setting the section area that is continuous in the coating material transport direction as the operation target section area, it is possible to change the substantial furnace length of the furnace, In addition, regardless of the change in the substantial furnace length, for one or a plurality of continuous sectioned areas (ie, the substantial operating part of the furnace) where the drying operation is performed, the coating material entrance and the exit of each sectioned area are provided. The provided door can effectively suppress the leakage of the hot air and the inflow of the cool air as described above.

In response to this change in the number of operation areas, the set tact time of the transfer means is changed (substantially, the coating material stop time in one heating zone is changed), so that each coating material is changed. The coating film drying time (that is, the passage time of each coated object in the substantially operating part of the furnace) can be adjusted to an appropriate time, and thus, the change of the number of operation areas and the corresponding change of the set tact time can be performed. Change the number of coated objects processed per unit time while avoiding excessive baking and insufficient baking due to improper coating film drying processing time, and maintaining the function of effectively preventing hot air leakage and cold air inflow. be able to.

As described above, according to the first aspect of the present invention, heat loss can be reduced and energy saving and operation cost can be reduced as compared with the above-mentioned conventional coating and drying furnace. In addition, it is possible to more effectively prevent the quality deterioration due to the inflow of the cool air and improve the finish quality of the coating film.

In particular, since the hot air leakage and the cold air inflow can be effectively suppressed in the substantially operating part of the furnace irrespective of a substantial change in the furnace length, the operation is performed when the number of coated articles processed per unit time is reduced. Energy consumption can be effectively reduced with the decrease in the number of compartments, and a high coating quality can be stably maintained even with a reduction in the number of coatings to be processed due to a substantial reduction in furnace length. In these respects, the advantages in energy saving, operation cost, and finish quality of the coating film can be further enhanced.

[0013] If the method of intermittently moving and transporting the coated article row as described above is adopted, the number of coated article processed per unit time is equal to that of the type of constantly moving (continuously moving) the coated article row. However, the required furnace length can be basically shortened, and the heat load from the furnace wall and the heating load at the time of starting operation can be reduced. According to this, the advantages in terms of energy saving and operation costs can be enhanced.

As for the door, only those located at the entrance and the exit of the substantially operating part of the furnace (that is, the substantial furnace entrance and the substantial furnace exit) are opened and closed in synchronization with the intermittent conveyance of the coating material row. Other doors located inside the substantially operating part of the furnace are kept open during the downtime of the coating, or not only those located at the entrance and exit of the substantially operating part of the furnace, but also those of the furnace. The other doors located inside the substantially movable part may adopt any of the operation modes of opening and closing in synchronization with the intermittent conveyance of the painted row, but if the latter operation mode is adopted, the compartments in which the operation is performed together The furnace air movement between adjacent areas can also be prevented, and the atmosphere in each of these divided areas can be more accurately and stably adjusted to the required atmosphere state. Even higher finish quality It can be.

[2] In the invention according to claim 2, a plurality of coating objects to be treated are conveyed in the furnace by the conveying means in a row state arranged in the conveying direction, and the coating of each of the coating objects is performed during the passage through the furnace. Regarding the operating method of the coating drying furnace for drying the film, the conveying means is operated by feeding every set tact time, and the coating is sequentially stopped in a plurality of heating zones arranged in the conveying direction in the furnace. An object row is intermittently conveyed, and the inside of the furnace is divided into a plurality of section areas including one heating zone or a plurality of continuous heating zones in one section area. In a state where doors are provided at the entrance and the exit, these doors are opened and closed in synchronization with the intermittent conveyance of the coating object row by the transfer means, and according to a change in the planned value of the number of coating articles processed per unit time, For the paint film in the area When the operation is performed in a plurality of divided areas, the number of the divided areas in which the drying operation is performed is changed in such a manner that the divided areas that are continuous in the coating material transport direction are set as the operation target divided areas. In response to the change in the number of areas, the set tact time is changed to adjust the coating film drying time of each coated article in the furnace to an appropriate time.

That is, by adopting this method, in the coating and drying furnace according to the first aspect of the present invention, it is possible to avoid excessive baking and insufficient baking due to improper coating film drying processing time as described above, While maintaining the function of effectively preventing leakage and inflow of cold air, the number of coatings processed per unit time can be changed according to the change in the planned value, saving energy, operating costs, and coating quality. And a high advantage can be obtained.

In carrying out this method, as described above, only the doors located at the entrance and the exit of the substantially operating part of the furnace are opened and closed in synchronization with the intermittent conveyance of the coating material row, as described above. Other doors located inside the substantially operating part of the furnace are open during the downtime of the coating, or are not only those located at the entrance and exit of the substantially operating part of the furnace, but also those of the furnace. Any of the operation modes of opening and closing the other doors located inside the target operating portion in synchronization with the intermittent conveyance of the coating object row may be adopted.

[3] According to a third aspect of the present invention, with respect to the method of operating the coating and drying furnace, a coating and drying furnace employing the operating method of the second aspect of the invention is provided as a coating and drying furnace for small adjustment, and the inside of the furnace is provided. A coating and drying furnace for large adjustments that intermittently conveys a row of painted objects in the furnace in the form of stopping each painted object sequentially in the heating zone and drying the coating film of each painted object in the process of passing through the furnace. The coating and drying furnace for the small adjustment is provided with the conveying means in an independent state, and whether or not to operate the coating and drying furnace for the large adjustment, and the selection in the coating and drying furnace for the small adjustment By combining the number of operation areas and the change in the set tact time, the number of coating objects processed per unit time is changed in multiple stages.

In other words, according to this method, a small adjustment paint drying furnace which enables the number of operation areas and the set tact time to be changed is juxtaposed, and each of these small adjustment paint drying furnaces is provided. By changing the number of operation areas and the set tact time, it is possible to change the number of coatings processed per unit time in multiple stages. With regard to the coating and drying furnace described above, it is not necessary to change the number of operation areas and the set tact time, so that the configuration of the furnace can be simplified accordingly, and the overall equipment cost can be reduced.

In addition, since the transfer means in the coating and drying furnace for the small adjustment and the transfer means in the coating and drying furnace for the large adjustment are independent from each other, in changing the number of coated articles per unit time as a whole, When it is no longer necessary to operate either the small adjustment paint drying oven or the large adjustment paint drying oven, the transport means of the stop drying oven is also stopped, and the necessary power Can be reduced, thereby making it more advantageous in terms of energy saving and operation cost.

It is desirable to provide a door which opens and closes at the entrance and the exit of the coating drying oven for large adjustment in synchronization with the intermittent conveyance of the coated product line.

The number of large-scale coating / drying furnaces is not limited to one, and a plurality of large-scale coating / drying furnaces are installed and each of these large-scale coating / drying furnaces is operated. The combination of the selection of whether or not and the change in the number of operation areas and the set tact time in the coating drying furnace for small adjustment may be changed in multiple stages of the number of coated articles processed per unit time. .

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] Hereinafter, a coating and drying facility employing a first embodiment of a method for operating a coating and drying oven according to the present invention will be described with reference to FIGS. In the coating and drying equipment, a coating and drying furnace L1 for small adjustment and a coating and drying furnace L2 for large adjustment are provided in a state where a conveyor T as a transport means is independently provided, and controls various controls of the coating and drying equipment. A control device 1 and an operation panel 2 for instructing the control device 1 with various control information are provided.

Each of the coating and drying furnaces L1 and L2 has a furnace body F,
In a mode in which the coating material w (in the present embodiment, the automobile body) is sequentially stopped in the plurality of heating zones 5 arranged in the transport direction in the furnace body F, the coating material row is intermittently transported by feeding operation every set tact time. It is provided with a floor-mounted tact type conveyor T as a transporting means. In addition, a combustion type heating device 11 for generating heated air as a heat source for heating the inside of the furnace, and an exhaust fan 21 for exhausting the inside of the furnace.
Is configured to be used in both furnace bodies F.

The furnace body F will be further described with reference to FIGS. The oven bodies F of the respective coating and drying ovens L1 and L2 have substantially the same configuration, and in the following description, different configurations for small adjustment and large adjustment will be distinguished from each other. The configuration will be described without particular distinction. The inside of the tunnel-shaped furnace 3 is divided into an inlet-side air seal zone 4, four heating zones 5, and an outlet-side air seal zone 6, which are arranged along the direction of transport of the coating material.
The four heating zones 5 are first, second, third, and so on, respectively, from the upper side to the lower side in the direction of transporting the painted object.
Called fourth. The inlet-side air seal zone 4, the four heating zones 5 and the outlet-side air seal zone 6 have the same length in the direction of transport of the coating material.

[0026] Then, the coating material entrance of the inlet side air seal zone 4, between the inlet side air seal zone 4 and the first heating zone 5, between the fourth heating zone 5 and the outlet side air seal zone 6, and A door 7 that can be freely opened and closed is provided at each of the carry-out ports of the outlet-side air seal zone 6.
Furthermore, in the furnace body 3 of the coating drying furnace L1 for small adjustment,
A door 7 is also provided between the third heating zone 5 and the third heating zone 5. That is, the coating drying furnace L1 for small adjustment
The furnace body 3 is divided into two divided areas E, a divided area E composed of first and second heating zones 5 and a divided area E composed of third and fourth heating zones 5. A door 7 that opens and closes the entrance and exit of each area E is provided.

In each heating zone 5, on the floor, a pair of air supply chambers 8 having hot air blowouts 8a are provided on the left and right sides in the direction of transporting the coating material, and the gas in the area is circulated below the ceiling. Suction chamber 9 having a suction port 9a formed therein. Furthermore, a heating zone is provided at the ceiling at the boundary between the first heating zone 5 and the second heating zone 5 and at the ceiling at the boundary between the third heating zone 5 and the fourth heating zone 5. An exhaust port 10 for exhausting the gas in 5 is provided.

A single combustion type heating device 11 is provided for both furnace bodies 3 for generating heated air as a heat source for heating the inside of the furnace. The burner 11b is configured to heat the passing fresh air by the combustion operation. Inverter control unit INV
The heating air circulation path 13 provided with a fresh air supply fan 12 whose blowing amount can be adjusted by the means is connected to the fresh air supply port and the fresh air supply port of the combustion type heating device 11, and the fresh air supply path 14 is connected. A temperature sensor 24 connected to the heated air circulation path 13 and detecting the temperature of air flowing through the heated air circulation path 13 is provided. Then, the fresh air supply fan 14 ventilates the fresh air supply passage 14 while adjusting the combustion amount of the combustion type heating device 11 so that the temperature detected by the temperature sensor 24 becomes the preset heating air temperature. Is heated by the combustion type heating device 11 so that the heated air heated and adjusted to the set heated air temperature is heated air. The circuit 13 is configured to circulate.

In each heating zone 5, an air supply chamber 8
And the suction chamber 9 are connected by a local air circulation path 15, and a heating air supply path 16 corresponding to each heating zone 5 is separately branched from the heating air circulation path 13, and the local air circulation of each heating zone 5 is performed. Each heating zone 5
Is connected to the heating air supply path 16 corresponding to the above. In each of the internal air circulation paths 15, a portion from the connection with the heated air supply path 16 to the air supply chamber 8 is provided with an internal air circulation fan 1 whose air flow can be freely adjusted by an inverter control unit INV.
7, a temperature sensor 18 for detecting the temperature of the flowing gas as a zone temperature is provided in a portion from the suction chamber 9 to a connection portion with the heated air supply channel 16 in the air circulation path 15 in each area. is there. Each heating air supply path 16 is provided with an adjustment damper 19 for intermittently supplying the heating air from the heating air circulation path 13 to the internal air circulation path 15 and adjusting the supply amount.

Each exhaust port 10 is connected to a corresponding individual exhaust path 20, and each exhaust path 20 is connected to an exhaust collective path 21. Each exhaust path 20 has an adjustment for adjusting the amount of exhaust. A damper 22 is interposed, and an exhaust fan 23 whose exhaust air volume can be adjusted by an inverter control unit INV is interposed in the exhaust collecting passage 21.

Then, by the ventilation action of the internal air circulation fan 17, the internal gas sucked through the suction port 9 a of the suction chamber 9 is passed through the internal air circulation path 15, and the hot air blowout 8 a of the air supply chamber 8 is heated by the heating zone. 5 circulates the gas in the heating zone 5, and in parallel, supplies fresh heating air from the heating air supply passage 16 to the in-region air circulation passage 15, thereby convection in the heating zone 5. Heat with. Further, by the ventilation action of the exhaust fan 23, the gas in the heating zone 5 is exhausted through each exhaust path 20 to ventilate the inside of the heating zone 5,
The gas in the region flowing therethrough is collected in the exhaust collecting passage 21 and sent to an exhaust processing device (not shown).

With respect to the furnace body F of the small adjustment coating drying furnace L1, the air circulation fans 17 of the heating zone 5 belonging to each of the divided areas E are operated, and the adjustment dampers 19 for adjusting the supply amount of the heated air are provided. Opening and opening the adjustment dampers 22 for adjusting the displacements respectively corresponding to the respective heating zones 5 in the operation execution state.
By stopping the internal air circulation fan 17 and closing the adjustment dampers 19 for adjusting the supply amount of heated air and closing the respective adjustment dampers 22 for adjusting the exhaust air amount, the operation can be stopped. . That is, each of the two divided areas E is configured such that the drying operation for the paint film can be individually stopped.

On the other hand, for the furnace body F for large adjustment,
The configuration is such that all the heating zones 5 are switched to a collective operation state or a collective stop state.

Next, the conveyor T will be described with reference to FIGS. The conveyors T of the respective coating and drying furnaces L1 and L2 have the same configuration, and are configured so that operation can be individually stopped. Further, the conveyor T of the small adjustment coating drying furnace L1 is configured so that the set tact time can be changed. Hereinafter, the configuration will be described for one conveyor T. A drive sprocket (not shown) in which an endless chain 34 in which engaging portions 33 of the cart 31 for mounting the painted object are engaged with the engaged portions 32 at a predetermined pitch are distributed to an inlet portion and an outlet portion of the furnace body 3. And the driven sprocket (not shown), and the endless chain 34 is intermittently rotated in one direction, so that the engaging portion 33 of the forward side chain portion is engaged with the engaged portion 32 of each carriage 31. In the engaged state, the plurality of painted objects w arranged in a line are conveyed intermittently. In FIG. 2, 35 is a wheel 36 of the truck 31.
Is a guide rail.

The arrangement pitch at which the coating objects w are arranged in a row is the same as the arrangement pitch of the heating zones 5, and the feeding pitch of the conveyor T is the same as the arrangement pitch of the heating zones 5. Then, the conveyor T is fed and operated at every set tact time, so that the coating object row is intermittently transported in a state where each coating object w is sequentially stopped in the four heating zones 5.

The operation panel 2 includes an operation switch (not shown) for instructing start and stop of the coating and drying equipment, and an operation select switch 2s for instructing operation at different operation.
Is provided. The operation rate indicates the ratio of the planned value of the number of coated articles processed per unit time to the maximum possible number of processed coated articles w per unit time in the coating and drying equipment, and instructs the change of the operation rate. Is equivalent to instructing a change in the planned value of the number of coated articles processed per unit time. Incidentally, in this embodiment, as the operation degree,
It is designed to instruct four operation rates of 100%, 75%, 50%, and 25%.

Next, the control configuration of the control device 1 will be described. The control device 1 basically performs the drying operation for the coating film on the coating film in the section area E with respect to the small-adjustment coating drying furnace L1 in accordance with the operation degree instructed from the operation panel 2. When the number of areas of the area E is to be operated in a plurality of section areas E, the section area E that is continuous in the coating material transport direction is changed to a section area E to be operated, and the number of operation execution areas is changed. Changes to
Changing the set tact time to adjust the coating film drying processing time of each coating material w in the furnace to the set coating film drying processing time t, and selecting whether or not to operate the large adjustment coating drying furnace L2 In this case, the number of coatings processed per unit time is changed over multiple stages.

The operation panel 2 will now be described with reference to FIGS.
Large-scale coating and drying furnace L according to the operation degree commanded by
The method for selecting whether or not to operate No. 2 and changing the number of operation areas and the set tact time in the small adjustment coating drying furnace L1 will be specifically described. FIG.
Indicates the operation state of each heating zone 5 at each operation degree, the heating zone 5 with hatching indicates the operation execution state, and the heating zone 5 without hatching indicates the operation stop state. FIG. 4 shows that, in the coating drying furnace L1 for small adjustment, the coating material w passes through the heating zone 5 of the partitioned area E where the operation is being performed for a set coating film drying processing time t. 5 shows a temporal change pattern in which a film temperature changes. In FIG. 4, the heating zone 5 to be operated is
Are shown in the order of arrangement in the article transport direction,.

When the 100% operation degree is commanded, the large-adjustment coating / drying furnace L2 is operated, and with respect to the small-adjustment coating / drying furnace L1, the furnace main body F is operated in both the two divided areas E. While driving in all zone driving conditions,
The conveyor T operates at the set tact time t / 4.

When a 75% operation degree is instructed, the large-adjustment coating / drying furnace L2 is operated. With respect to the small-adjustment coating / drying furnace L1, the furnace main body F is moved to the area E on the upper side in the transport direction of the coated object. The conveyor T is operated in a set tact time t / 2 while the operation is being performed, and the operation is performed in a partial zone operation state in which the partitioned area E on the lower side in the coating material conveyance direction is stopped.

When a 50% operation rate is instructed, the large-adjustment coating / drying furnace L2 is operated, and with respect to the small-adjustment coating / drying furnace L1, the two divided areas E are stopped and the furnace body F is stopped.
Is stopped, and the conveyor T is also stopped.

When a 25% operation degree is instructed, the large adjustment coating drying furnace L2 is stopped (the conveyor T is also stopped together with the furnace main body F). While operating in the zone operation state, the conveyor T operates at the set tact time t / 2.

Therefore, in the small-adjustment coating drying furnace L1, the drying process is performed for the set coating film drying time t in both the full zone operation state and the partial zone operation state. Drying is performed at the set coating film drying time t.

The control device 1 also includes a small adjustment coating drying oven L
When the first furnace body F is operated in the all zone operation state, the door 7 between the second and third heating zones 5 is kept open, and all the other doors 7 are moved to the conveyor T. In the state where the coating object w is stopped in the heating zone 5 while the coating object w is stopped in the heating zone 5, the coating object w is carried into or out of the heating zone 5. Opening and closing operations to allow When the furnace body F of the small adjustment coating drying furnace L1 is operated in the partial zone operation state, all the doors 7 including the doors 7 between the second and third heating zones 5 are moved to the conveyor T. In accordance with the transfer timing, while the coating object w is stopped in the heating zone 5, the coating object w is carried into or out of the heating zone 5 while being kept closed. Opening and closing operations to allow for In addition, when the large adjustment coating drying furnace L2 is operating, all the doors 7 are kept in a closed state while the coating material w is stopped in the heating zone 5 in synchronization with the transport timing of the conveyor T. In this state, the opening / closing operation is performed so as to allow the coating object w to be carried into or out of the heating zone 5.

A set zone temperature is set in advance for each of the four heating zones 5 of each furnace body F. The set zone temperature is set to be the same in each heating zone 5, for example.

Then, the control device 1 determines that the temperature detected by the temperature sensors 18 of the respective heating zones 5 in the section area E to be operated becomes the set zone temperature for the furnace main body F of the small adjustment coating and drying furnace L1. In addition, the adjustment dampers 19 are adjusted to adjust the supply amount of the heating air, and the respective adjustment dampers 22 for adjusting the displacement are adjusted to the supply amounts of the heating air to the two corresponding heating zones 5. The air balance of each heating zone 5 is maintained by adjusting the exhaust volume. Further, with respect to the furnace body F of the large adjustment coating drying furnace L2, the adjustment damper 19 is adjusted so that the temperature detected by the temperature sensor 18 in each heating zone 5 becomes the set zone temperature, and the exhaust amount is adjusted. Each adjustment damper 22 of
Adjustment is performed so that the exhaust air amount matches the supply amount of the heated air to the two corresponding heating zones 5. or,
The amount of exhaust air from the exhaust fan 23 is adjusted by the inverter control unit INV so that the amount of exhaust air from each exhaust port 10 becomes equal to the amount of heated air supplied to the corresponding two heating zones 5.

When the coating material w passes through the furnace, since the temperature of the coating material w which is carried in is lower in the heating zone 5 located on the upper side in the coating material transport direction and the heat load is higher, the heating zone 5 is heated. The supply amount of air and the exhaust amount of gas in the region increase. In addition, the more the heating zone 5 located on the upper side in the transport direction of the coated object, the larger the amount of solvent evaporation from the coating film of the coated object w.
As described above, since the ventilation zone is larger at the heating zone 5 located on the upper side in the transporting direction of the coating material, the required ventilation volume is secured. Incidentally, the lower the temperature of the heating air supplied to the heating zone 5, the larger the supply amount of the heating air supplied to adjust the zone temperature to the set zone temperature, and accordingly the larger the exhaust amount, The set heating air temperature is set so that the required ventilation volume of each heating zone 5 can be secured.

In the coating / drying furnace L1 for small adjustment, in both the full zone operation state and the partial zone operation state, when the coating material w sequentially passes through the heating zone 5 during the operation, the coating film temperature becomes higher. As shown in FIG. 4, the temperature gradually increases with the passage of time from the start of the drying process, and changes in a time-dependent change pattern such that when the temperature reaches a predetermined temperature, the temperature is maintained at the predetermined temperature. It is possible to sequentially execute a heating step of gradually elevating the temperature of the coating film to evaporate the coating solvent and a heating step of maintaining the coating film temperature at a predetermined temperature and effecting the reaction of the coating film.

In the large-adjustment coating / drying furnace L2, the drying process is executed in the same manner as in the operation of the small-adjustment coating / drying furnace L1 in all zones.

The air circulation amount in the set area is set for each of the temperature raising step and the temperature maintaining step, and the process (the temperature raising step or the temperature maintaining step) assigned to each of the heating zones 5 during the operation is performed. The air flow rate of the internal air circulation fan 17 is adjusted by the inverter control unit INV so that the internal air circulation amount becomes the set area corresponding to the step (3).

[Second Embodiment] A description will be given below, with reference to FIGS. 5 and 6, of a coating and drying facility employing a second embodiment of the method for operating a coating and drying furnace according to the present invention. Paint drying equipment
A coating / drying furnace having a furnace body F and a floor-mounted tact-type conveyor T, and a control device 1 for controlling various controls of the coating / drying equipment.
And an operation panel 2 for instructing the control device 1 of various control information
And is configured. In FIG. 5, the illustration of the conveyor T is omitted.

The furnace body F will be described with reference to FIG. The inside of the tunnel-shaped furnace body 3 is divided into an inlet-side air seal area 4, eight heating zones 5, and an outlet-side air seal area 6, which are arranged along the direction of transporting the coating material. The carry-out port and each zone are separated by a door 7 that can be freely opened and closed. All eight heating zones 5 have the same length in the transport direction of the painted object. The compartment area E is constituted by one heating zone 5, and the inside of the furnace is partitioned into eight compartment areas E, and a door 7 for opening and closing the entrance and exit of the coating material in each of these compartment areas E is provided. It is.

The same combustion type heating device 11 as in the first embodiment.
And a heating air circulation path 13 provided with a fresh air supply fan 12 whose air flow is adjustable by an inverter control unit INV is connected to a fresh air supply port and a heating air supply port of the combustion type heating device 11. , The fresh air supply path 14 is connected to the heated air circulation path 13,
Is provided with a temperature sensor 24 for detecting the temperature of the flowing air.

Each heating zone 5 is provided with a pair of air supply chambers 8 each having a suction port 8a and a suction chamber 9 having a suction port 9a, as in the first embodiment. 5 is provided with an exhaust port 10. Then, similarly to the first embodiment, the air supply chamber 8 and the suction chamber 9 are connected by the local air circulation path 15, and the heating air circulation paths 13 correspond to the heating air supply paths 16 corresponding to the respective heating zones 5. Are separately branched, and a heating air supply path 16 corresponding to each heating zone 5 is connected to the in-region air circulation path 15 of each heating zone 5. As in the first embodiment, each intra-region air circulation path 15 is provided with an inter-region air circulation fan 17 whose air flow can be adjusted by an inverter control unit INV and a temperature sensor 18.
Further, an adjustment damper 19 is interposed in each heating air supply path 16 as in the first embodiment. The exhaust port 10 of each heating zone 5 is connected to an individual exhaust path 20 corresponding to each, and each exhaust path 20 is connected to an exhaust collective path 21. The exhaust collecting passage 21 is provided with an exhaust fan 23 whose air flow is adjustable by an inverter control unit INV.

In each of the divided areas E, the corresponding internal air circulation fan 17 is operated, the adjustment damper 19 for adjusting the supply amount of the heated air is opened, and the adjustment damper 22 for adjusting the exhaust air amount is also provided. By opening, the operation air-conditioning fan 17 is stopped, the corresponding internal air circulation fans 17 are stopped, and the adjustment dampers 19 for adjusting the supply amount of the heated air are set.
, And the corresponding adjustment dampers 22 for adjusting the displacement are closed, whereby the operation can be stopped. That is, each of the eight divided areas E is configured so that the drying operation for the paint film can be individually stopped.

The conveyor T has the same configuration as that of the first embodiment. The arrangement pitch at which the coating objects w are arranged in a line is the same as the arrangement pitch of the heating zones 5, and the feed pitch of the conveyor T is also the arrangement of the heating zones 5. The pitch is the same. And
By feeding and operating the conveyor T at every set tact time, the coating material row is intermittently conveyed in a state where each coating material w is sequentially stopped in the eight heating zones 5.

The operation panel 2 has 100%, 87.5%, 7%
5%, 62.5%, 50%, 37.5%, 25% and 1
An operation rate selection switch 2s for instructing operation at 2.5% of operation rates is provided.

Next, the control configuration of the control device 1 will be described. The control device 1 basically sets the number of areas of the section area E in which the drying operation is performed on the paint film among the eight section areas E in accordance with the operation degree instructed from the operation panel 2. When the operation is carried out in the section area E, the section area E which is continuous in the paint conveying direction is changed to the section area E to be operated, and the set tact time is set in response to the change in the number of operation areas. Is changed to adjust the coating film drying processing time of each coating product w in the furnace to the set coating film drying processing time t.

Hereinafter, a method for changing the number of operation areas and the set tact time according to the operation rate instructed from the operation panel 2 will be specifically described with reference to FIG.
FIG. 6 shows a time-dependent change pattern in which the temperature of the coating film changes as the coating material w passes through the heating zone 5 of the partitioned area E during the operation for the set coating film drying time t. The heating zones 5 to be operated are indicated by the order of arrangement in the direction of transport of the painted object,.

The number of operation areas is determined by a plurality of partition areas E
In the case where the operation is carried out, the section area E which is continuous from the uppermost part in the direction of transporting the coating material to the lower side in the direction of transporting the coating material is set as the partition area E to be operated. When the operation rate is 100%, eight sections are provided. 7 at 77.5%, 6 at 75%
Thereafter, as the instructed operation degree decreases by one step, the operation degree is decreased by one, and when the operation rate is 12.5%, each is changed to one. Note that one heating zone 5 that is operated when the operation rate is 12.5% is the uppermost heating zone in the coating material transport direction.

Next, the set tact time of the conveyor T is adjusted to a time obtained by dividing the drying processing time t by the number of operation areas. That is, when the operation rate is 100%, the number of operation execution areas is 8, so the set tact time is t / 8,
When the operation rate is 87.5%, the number of operation execution areas is seven, so the set tact time is t / 7, and when the operation rate is 12.5%, the number of operation operation areas is one. Therefore, the set tact time is t.

Therefore, in the operation at any operation degree, the drying process is performed at the set coating film drying time t.

Further, while the door 7 is kept closed in the heating zone 5 while the coating material w is stopped in the heating zone 5 in synchronization with the transport timing of the conveyor T, the coating material w moves to the heating zone 5. An opening / closing operation is performed so as to allow loading or unloading from the heating zone 5.

As in the first embodiment, a set zone temperature is set in advance for each heating zone 5. The set zone temperature is set to be the same in each heating zone 5, for example. Then, the control device 1 adjusts the adjustment damper 19 so that the detected temperature of the temperature sensor 18 of the heating zone 5 becomes the set zone temperature with respect to each of the section areas E to be operated, and also adjusts each of the exhaust volume adjustment. The adjustment dampers 22 are adjusted so that the exhaust amount is matched to the supply amount of the heated air to the corresponding heating zone 5, and the exhaust amount from each exhaust port 10 is set to a value corresponding to the heating of the corresponding heating zone 5. The exhaust air amount of the exhaust fan 23 is adjusted by the inverter control unit INV so that the exhaust air amount matches the air supply amount. Accordingly, when the coating material w passes through the heating zone 5 during the operation, the coating film temperature is reduced as shown in FIG.
As shown in the figure, the temperature gradually increases with the lapse of time from the start of the drying process, and when the temperature reaches a predetermined temperature, the temperature changes in a time-dependent change pattern such that the temperature is maintained at the predetermined temperature. And the drying process which performs a heat retention process sequentially can be performed.

Incidentally, when the operation rate is low and the number of operation areas is small, or when the operation rate is 1 such as when the operation rate is 12.5%, the coating material w stops in the heating zone 5. During the initial period, the heat load is large due to the low temperature of the incoming painted object w, and thereafter, the temperature of the painted object w gradually increases and the thermal load gradually decreases. The temperature changes in a time-dependent change pattern as shown in FIG. 6, and the amount of ventilation increases in the early stage of the drying process, so that the required amount of ventilation can be secured, and thereafter, it gradually decreases.

[Another Embodiment] Next, another embodiment will be described. (A) In the first embodiment described above, the case where the number of the heating zones 5 constituting the divided area E of the small adjustment coating / drying furnace L1 is set to two is exemplified. If it is set to one, the change width of the operation rate can be set to 12.5% as in the second embodiment. In this case, an individual exhaust port 10 is provided in each heating zone 5, an individual exhaust path 20 corresponding to each exhaust port 10 is connected to each exhaust port 10, and an adjustment damper 2 capable of adjusting the amount of ventilation to each exhaust path 20.
2 is interposed.

Alternatively, the number of heating zones 5 in the small-adjustment coating drying furnace L1 may be increased, and the number of heating zones 5 constituting the divided area E may be set to three or more.

A plurality of large-adjustment coating / drying furnaces L2 are provided in such a manner that they can be individually stopped and operated, and it is selected whether or not to operate each of these large-adjustment coating / drying furnaces L2. The operation degree may be changed in combination with the change in the number of operation execution areas and the set tact time in the furnace L1.

The number of heating zones 5 provided in each of the small-adjustment coating drying oven L1 and the large-adjustment coating drying oven L2 can be appropriately changed according to the required adjustment range of the operation degree.
In this case, the number of heating zones 5 may be different between the small adjustment coating drying furnace L1 and the large adjustment coating drying furnace L2. .

(B) In the second embodiment,
Although the case where the number of the heating zones 5 constituting the partitioned area E is set to one has been illustrated, it may be set to a plurality.
Further, the number of heating zones 5 provided in the coating and drying furnace can be appropriately changed according to the required adjustment range of the operation degree.

(C) In the juxtaposed row of the plurality of section areas E in the coating and drying furnace, the form of setting the position of the section area E in which the operation is to be performed is as described in each of the above embodiments. The present invention is not limited to the form set to be biased to the side end, and may be, for example, a form set to the lower side end in the paint conveying direction or a form set to an intermediate part in the paint conveying direction.

(D) In the first embodiment,
An operation panel 2 for instructing the operation degree is provided, and the control device 1
According to the operation degree instructed from the operation panel 2, the number of operation areas and the set tact time for the small adjustment coating drying furnace L1 are changed, and whether or not the large adjustment coating drying furnace L2 is operated is selected. The case where it is configured to execute automatically is exemplified. Instead, a small adjustment coating drying oven L
A switch for switching between the operation execution state and the operation stop state and a switch for changing the set tact time are provided corresponding to each of the division areas E, and the large adjustment coating drying furnace L2 is set to the operation execution state. Switches for switching to the operation stop state are provided, and the switches are used to artificially change the number of operation execution areas and the set tact time, and select whether or not to operate the large adjustment coating drying furnace L2. May be configured. Similarly, in the second embodiment, instead of the configuration in which the control device 1 automatically changes the number of operation execution areas and the set tact time, the operation execution state and the operation stop state are respectively corresponded to the division areas E. And a switch to change the set tact time, and by those switches,
The number of operation areas and the set tact time may be changed.

(E) As a heating method for heating the heating zone 5, the convection method is employed in the above embodiment, but a radiation method may be employed instead.
A system using both a convection type and a radiation type may be adopted.

(F) The coating w is not limited to the automobile body, but may be a casing of a home electric appliance or the like.

[Brief description of the drawings]

FIG. 1 is a block diagram of a coating and drying facility that employs a method for operating a coating and drying furnace according to a first embodiment.

FIG. 2 is a vertical cross-sectional view in a direction perpendicular to a direction in which a coating material is conveyed in a coating drying furnace according to the embodiment.

FIG. 3 is a diagram for explaining a method of changing the number of operation execution areas in the operation method of the coating and drying furnace according to the first embodiment.

FIG. 4 is a diagram for explaining a method of changing the number of operation execution areas and a set tact time in the method for operating the coating and drying furnace according to the first embodiment.

FIG. 5 is a block diagram of a coating and drying facility that employs a method for operating a coating and drying furnace according to a second embodiment.

FIG. 6 is a view for explaining a method of changing the number of operation execution areas and a set tact time in an operation method of a coating and drying furnace according to a second embodiment.

[Explanation of symbols]

 5 Heating zone 7 Door w Painted material E Sectional area L1 Paint drying furnace for small adjustment L2 Paint drying furnace for large adjustment T Transport means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sadakunori 100, Kanayama, Ichiriyama-cho, Kariya-shi, Aichi Toyota Auto Body Co., Ltd. (72) Inventor Etsuo Kawahara 2-6-1 Nishishinjuku, Shinjuku-ku, Tokyo Stock In-house company (72) Inventor Hideo Kobori 2-6-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo F-term company (reference) 3L113 AA02 AB02 AB06 AC04 AC35 AC48 AC49 AC56 AC65 AC73 AC75 BA32 BA33 CA08 CB23 CB27 DA02 DA06 DA24 4D075 BB24Z DC12 4F042 AA09 DB04 DB12 DB14 DF15 DF22

Claims (3)

[Claims] 1. A coating and drying furnace in which a plurality of coated objects to be processed are conveyed in a furnace by a conveying means in a row state arranged in a conveying direction, and a coating film of each coated object is dried in a process of passing through the furnace. There is a configuration in which the transfer means is configured to sequentially stop each coated object in a plurality of heating zones arranged in the transfer direction in the furnace, and to perform a feed operation every set tact time to intermittently transfer the coated object row. And dividing the inside of the furnace into a plurality of compartment areas including one heating zone or a plurality of continuous heating zones in one compartment area, and opening / closing a coating material entrance and an exit of each of these compartment areas. Coating drying oven, wherein the transport means is configured to be capable of changing the set tact time, and each of the divided areas is configured to be capable of individually stopping a drying process operation for a coating film of a coating material. . 2. A coating and drying furnace in which a plurality of coating objects to be processed are conveyed in a furnace by a conveying means in a row state arranged in a conveying direction, and a coating film of each of the coating objects is subjected to a drying process during the passage through the furnace. An operation method, wherein the feeding means is operated by feeding every set tact time,
A row of coated articles is intermittently transported in a form in which each coated article is sequentially stopped in a plurality of heating zones arranged in the transport direction in the furnace, and one heating zone or a plurality of continuous ones in one section area in the furnace. The heating zone is divided into a plurality of section areas, and in the state where doors are provided at the entrances and exits of the coating material in each of these division areas, these doors are used for the intermittent conveyance of the coating material row by the conveyance means. It opens and closes synchronously, and in response to a change in the planned number of painted objects per unit time,
The number of sections of the section area in which the drying process is performed on the coating film of the coating material in the section areas, and when performing the operation in a plurality of section areas, the section area that is continuous in the coating material transport direction is the section area to be operated. A method for operating a paint drying furnace, wherein the set tact time is changed to adjust the coating film drying time of each coated article in the furnace to an appropriate time in response to the change in the number of operation areas. 3. A coating / drying furnace adopting the operation method according to claim 2 is provided as a coating / drying furnace for small adjustment, and the coating material rows are intermittently stopped in a form in which each coating material is sequentially stopped in a heating zone in the furnace. A large-scale coating and drying furnace that transports in the furnace to dry the coating film of each coated material in the process of passing through the furnace,
The coating and drying furnace for the small adjustment is provided in a state where the conveying means is independent, and selection of whether to operate the coating and drying furnace for the large adjustment and
A method for operating a coating / drying furnace in which the number of operation areas and a set tact time in the coating / drying furnace for small adjustment are combined to change the number of processed articles per unit time in multiple stages.