JP2019184210A - Coating drying furnace - Google Patents

Abstract

To provide a coating drying furnace capable of effectively realizing both treatment-quality improvement by preventing dust from floating and heat-loss reduction by preventing furnace gas from leaking and by preventing outside air from entering into the furnace.SOLUTION: The coating drying furnace that prevents high temperature furnace gas from leaking outside the furnace through a furnace body opening part 2 by virtue of an air stream curtain Cb formed across the furnace body opening part 2 by an air stream fb blown out of a blowout port 5 for forming an air stream curtain and prevents normal temperature outside air from entering into the furnace through the furnace body opening part 2, is provided with wind shield dams 12a, 12b functioning as resistance to an air stream flowing on a floor FL of the furnace body opening part 2 in the travelling direction of a treating object, the wind shield dams 12a, 12b disposed on the floor FL of the furnace body opening part 2 on a colliding position t of the air stream curtain Cb on the floor FL of the furnace body opening part 2, or on neighboring positions ta, tb with respect to the colliding position t in the travelling direction of a treating object.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a coating drying furnace that performs a coating film drying process on an object to be processed such as an automobile body that has undergone a coating process. Specifically, the present invention relates to a processing object to be carried from the outside of the furnace to the inside of the furnace or to the outside of the furnace from the inside of the furnace. A blowout opening for forming an airflow curtain is provided in the ceiling of the furnace body opening through which the processed object to be processed passes, and the airflow blown out from the blowout opening is formed by the airflow curtain formed in the furnace body opening. Further, the present invention relates to a paint drying furnace in which leakage of high-temperature gas in the furnace to the outside of the furnace through the furnace body opening and intrusion of room-temperature air outside the furnace into the furnace through the furnace body opening are prevented.

  With regard to this type of paint drying furnace (see FIGS. 1 to 4), an air current is passed through the object passage area 2 a in the furnace body opening 2 as an air outlet for forming an airflow curtain provided in the ceiling 3 of the furnace body opening 2. The left and right side blows that individually form the air flow curtains Cb in the central air outlet 4 that forms the curtain Ca and the gap areas 2b between the left and right side walls 6 and the object passage area 2a in the furnace body opening 2. An outlet 5 is provided, and each of the left and right side outlets 5 has an airflow fb for forming an airflow curtain obliquely downward with a large inclination angle θb with respect to the horizontal direction toward the inside of the furnace or vertically downward. On the other hand, the central outlet 4 previously proposed a paint drying furnace in which the airflow fa for forming the airflow curtain is blown out toward the inside of the furnace with the inclination angle θa with respect to the horizontal being small and downward (patent) Reference 1).

  That is, in the paint drying furnace proposed in Patent Document 1, the airflow fa blown from the central outlet 4 has a small inclination angle θa with respect to the horizontal and passes through the object passage area 2a as shown in FIG. Since the incident angle θin with respect to the upper surface of the processing object B is large, the air flow smoothly flows along the upper surface of the processing object B following the formation of the airflow curtain Ca. Bounce due to collision is effectively suppressed.

  As a result, the air flow fa blown out from the central outlet 4 is in a state of stably forming an air flow curtain Ca without turbulence above the processing object B, whereby the furnace body opening of the in-furnace hot gas G Leakage to the outside of the furnace through 2 is further effectively prevented, and reduction of heat loss through the furnace body opening 2 is more effectively achieved.

Japanese Patent Application No. 2017-118852 Special table 2013-519856 gazette

  However, if the blowout air velocity and the blowout air amount of the airflow fb at the airflow curtain forming air outlet (especially the side air outlet 5 described above) are increased, the area shielding effect itself by the airflow curtain Cb is increased, but on the other hand, FIG. As shown in FIG. 4, the blown air flow fb collides with the floor FL of the furnace body opening 2 and is scattered widely around the furnace body opening 2 after the formation of the air flow curtain Cb. As the dust soars at the surface of the object, the quality of the process tends to deteriorate due to the dust dust adhering to the processing object B.

  Further, the blown air flow fb collides with the floor FL of the furnace body opening 2 following the formation of the air flow curtain Cb and is widely scattered around, so that the air volume of the post-impact air flow fb ″ flowing out of the furnace due to the scattering. As a result, the amount of heat taken out to the outside of the furnace increases due to the increase in the amount of outflow air, thereby causing a problem that the effect of reducing the heat loss due to the formation of the airflow curtain Cb is limited.

  And these problems are not limited to the coating and drying furnace proposed in Patent Document 1, but as shown in Patent Document 2 (see FIG. 26), the airflow has a uniform inclination posture across the entire width of the furnace body opening 2. This also occurs in the coating and drying furnace in which the curtain C is formed. In particular, in the case where the airflow curtain C having a uniform inclination posture is formed over the entire width of the left and right sides of the furnace body opening 2, the above-mentioned rising dust is generated. And the problem of the outflow of the airflow after the collision to the outside of the furnace occur uniformly over the entire left and right width of the furnace body opening 2.

  In view of this situation, the main problem of the present invention is to effectively solve the above problem by adding a rational wind-shielding structure.

The first characteristic configuration of the present invention relates to a paint drying furnace,
An air outlet for forming an airflow curtain is provided at the ceiling of the furnace body opening through which the processing object to be carried into the furnace from the outside of the furnace or the processed processing object to be carried out of the furnace to the outside of the furnace passes. ,
Due to the airflow curtain formed by the airflow blown from the blowout opening at the furnace body opening, leakage of the high temperature gas in the furnace to the outside of the furnace through the furnace body opening, and the furnace body opening of the outside room temperature air A coating and drying furnace that is prevented from entering the furnace through the section,
On the floor of the furnace body opening, a windbreak weir is provided that resists airflow flowing in the direction of passage of the object to be processed.
The windbreak weir is located on the floor of the furnace body opening in the vicinity of the collision position of the airflow curtain on the floor of the furnace body opening or the processing object passing direction with respect to the collision part. .

  According to this configuration, even if the airflow blown out from the airflow curtain forming outlet and formed the airflow curtain at the furnace body opening collides with the floor of the furnace body opening and is scattered around, Scattering of the airflow in the passing direction (that is, scattering of the airflow in and out of the furnace) is effectively suppressed by the windshield weir becoming a resistance against the scattered airflow after the floor collision, Dust soaring and outflow of airflow after collision to the outside of the furnace are suppressed.

  In addition, the dust soaring and the outflow of the airflow after the collision to the outside of the furnace are suppressed in this way, and accordingly, the processing quality deteriorates due to the soaring dust adhering to the processing object and the airflow after the collision is outside the furnace. While avoiding an increase in the amount of heat that is taken out of the furnace due to the outflow to the furnace, the air flow at the outlet for forming the air flow curtain is increased and the air flow at the opening of the furnace body is further shielded by the air flow curtain. This makes it possible to more reliably prevent leakage of hot gas inside the furnace through the furnace opening and intrusion of room temperature air outside the furnace into the furnace through the furnace opening. It is possible to reduce the heat loss through the furnace body opening more effectively.

The second feature configuration of the present invention specifies an embodiment suitable for the implementation of the first feature configuration.
The windbreak weir is provided on the floor of the furnace body opening at each of the vicinity location outside the furnace and the vicinity location inside the furnace with respect to the collision location.

  According to this configuration, out of the scattering of the airflow generated when the airflow forming the airflow curtain collides with the floor of the furnace body opening, the scattering of the airflow facing the outside of the furnace is provided at a location near the outside of the furnace with respect to the collision location. The windbreak weir is surely restrained by the resistance of the windbreak weir, and the scattering of the airflow toward the furnace inside is reliably restrained by the resistance of the windbreak weir provided near the inside of the furnace with respect to the collision location.

  Therefore, the presence of these two windbreak weirs can more reliably prevent the dust from flying up and the flow of the airflow after the collision to the outside of the furnace, and the airflow velocity of the airflow at the outlet for forming the airflow curtain accordingly. Further, the area shielding effect by the airflow curtain can be further increased by further increasing the amount of blown air.

The third feature configuration of the present invention specifies an embodiment suitable for the implementation of the second feature configuration.
The distance between the wind shield weirs provided at the vicinity of the outside of the furnace with respect to the collision and the vicinity of the inside of the furnace is a correlation between the distance and the amount of heat loss through the furnace body opening. In this case, the distance dimension is such that the amount of heat loss through the furnace body opening is minimized.

  That is, when the windbreak weirs are provided in the vicinity of the outside of the furnace and the vicinity of the inside of the furnace with respect to the collision location, the distance dimension e between the windbreak weirs is changed under the same conditions. FIG. 14 shows the distance e between the wind shield weirs and the amount of heat loss per unit time, unit area, and unit temperature (= opening loss ΔR per unit) through the furnace body opening. It was recognized that there was such a correlation.

  Therefore, as the distance dimension e between the wind shield weirs provided at the vicinity of the outside of the furnace and the vicinity of the inside of the furnace with respect to the collision location, the interval at which the heat loss amount (= opening loss ΔR per unit) is minimized in this correlation. According to the third characteristic configuration employing the dimensions, reduction of heat loss through the furnace body opening can be achieved more reliably and more effectively in the implementation of the second characteristic configuration.

The fourth feature configuration of the present invention specifies an embodiment suitable for the implementation of either the second or third feature configuration, and the feature is:
The relative positional relationship in the processing object passage direction between the airflow curtain and the center position between the wind shield weirs provided at the vicinity location outside the furnace and the vicinity location inside the furnace with respect to the collision location, In the correlation between the relative positional relationship and the amount of heat loss through the furnace body opening, the relative position relationship is such that the amount of heat loss through the furnace body opening is minimized.

  In other words, when windbreak weirs are provided in the vicinity of the outside of the furnace and the vicinity of the inside of the furnace with respect to the collision location, the center position between the windbreak weirs and the coating of the airflow curtain are applied under the same conditions. When the relative positional relationship in the object passing direction was changed, the relative positional relationship (specifically, the relative positional relationship of K1 to K3 shown in FIG. 16) and the unit time / unit area / It was recognized that there is a correlation as shown in FIG. 15 between the amount of heat loss per unit temperature (= opening loss ΔR per unit).

  Therefore, the heat loss in this correlation is expressed as the relative positional relationship between the airflow curtain and the center position between the wind shield weirs provided at the vicinity of the outside of the furnace and the vicinity of the inside of the furnace with respect to the collision location. According to the fourth feature configuration adopting a relative positional relationship in which the amount (= opening loss ΔR per unit) is minimized, the heat through the furnace body opening in the implementation of the second feature configuration or the third feature configuration Loss reduction can be achieved more reliably and more effectively.

The fifth characteristic configuration of the present invention specifies an embodiment suitable for implementation of any of the first to fourth characteristic configurations,
As the outlet, a central outlet that forms the airflow curtain in the object passage area in the furnace body opening, and each gap area between the left and right sidewalls in the furnace body opening and the object passage area Left and right side air outlets for forming the air flow curtain separately,
From the central outlet, an airflow for forming an airflow curtain is blown out toward the furnace inside obliquely downward with a small inclination angle with respect to the horizontal,
From each of the left and right side air outlets, an airflow for forming an airflow curtain is blown out toward the furnace inside with a large downward inclination angle with respect to the horizontal, or downward vertically,
The windbreak weir is provided on the floor at a collision location on the floor of the airflow curtain formed by the airflow blown out from the left and right side air outlets or in a vicinity of the collision location in the passing direction of the object to be processed. It is in the point.

  In this configuration (see FIGS. 6 and 7), when the processing object B is present in the object passage area 2a in the furnace body opening 2, the airflow fa blown from the central outlet 4 has an inclination angle θa with respect to the horizontal. Since the incident angle θin with respect to the upper surface portion of the processing object B is small and becomes a form that flows along the upper surface portion of the processing object B, the rebound due to the collision with the upper surface portion of the processing object B is suppressed, Thereby, above the processing object B, the airflow fa blown from the central outlet 4 is in a state of stably forming the airflow curtain Ca without any disturbance.

  Therefore, when the processing object B is present in the object passage area 2 a of the furnace body opening 2, leakage of the high temperature gas G in the furnace through the upper area of the furnace body opening 2 to the outside of the furnace is caused from the central outlet 4. The airflow curtain Ca formed above the processing object B by the blown airflow fa, and the gaps between the airflow fb blown from the left and right side outlets 5 and the object passage area 2a and the side walls 6 This is effectively prevented by the airflow curtain Cb formed in the region 2b.

  Further, since the air flow fb blown out from the left and right side air outlets 5 is obliquely downward or vertically downward with a large inclination angle θb with respect to the horizontal, an airflow curtain Cb is formed in each gap region 2b. After reaching the floor portion FL of each gap area 2b, a part of the gap portion 2b effectively wraps around the processing object B, and the wrapping air flow fb 'below the processing object causes the lower part of the processing object B to move downward. Intrusion of outside-furnace room-temperature air O into the inside of the furnace in the state of diving is prevented.

  Therefore, when the processing object B is present in the object passage area 2a of the furnace body opening 2, the intrusion of the room temperature outside air O through the lower area of the furnace body opening 2 into the furnace is caused by the left and right side blows. The airflow curtain Cb formed in each gap region 2b by the airflow fb blown out from the outlet 5 and the above-described wraparound airflow fb ′ that wraps around the processing object B from the floor of each gap region 2b are effectively prevented. .

  On the other hand, when the processing object B is not present in the furnace body opening 2 (see FIGS. 4 and 5), the air flow fa blown out from the central outlet 4 toward the furnace inner side is inclined downward with a small inclination angle θa with respect to the horizontal. In addition to forming the airflow curtain Ca in the object passing area 2a by the absence of the processing object B and forming the airflow curtain Ca in the object passage area 2a, the furnace opening due to the absence of the processing object B 2 spreads to the respective gap regions 2b in the width direction of the airflow 2, and is blown out from the left and right side outlets 5 toward the furnace inside in a slanting downward direction with a large inclination angle θb with respect to the horizontal, or vertically downward. fb forms an airflow curtain Cb in each gap region 2b, and an airflow curtain formed by the airflow fa from the central outlet 4 due to the absence of the processing object B accompanying the formation of the airflow curtain Cb. It extends to the object passage area 2a in the lateral width direction of the furnace body opening 2 outside the furnace from Ca.

  Therefore, when the processing object B is not present in the furnace body opening 2, the airflow curtains Ca and Cb can be nearly doubled with respect to the entire furnace body opening 2. Leakage of the in-furnace hot gas G to the outside of the furnace through the upper area of the body opening 2 and intrusion of the out-of-furnace room temperature air O through the lower area of the furnace body opening 2 into the furnace are effectively prevented.

  Furthermore, in the fifth feature configuration (see FIG. 11), the windbreak weirs 12a and 12b that are resistant to the airflow flowing in the processing object passage direction on the floor FL are provided from the left and right side air outlets 5. Since the airflow curtain Cb formed in each gap region 2b by the blown airflow fb is provided on the floor FL at the collision point t on the floor FL or in the vicinity of the processing object passage direction ta and tb with respect to the collision point t. Even if the air flow fb blown out from the left and right side outlets 5 and formed the air flow curtain Cb collides with the floor FL and scatters to the surroundings, scattering of the air flow in the passing direction of the processing object B (that is, the furnace Scattering of the airflow in and out) is effectively suppressed by the resistance of the windbreak weirs 12a and 12b to the scattered airflow after the floor collision, and thereby, the rising of dust from the floor FL (particularly, ,processing Elephant product passes soar in the direction) and the outflow of the furnace outside of the post-collision air flow is suppressed.

  In addition, the dust soaring and the outflow of the airflow after the collision to the outside of the furnace are suppressed in this way, and accordingly, the processing quality deteriorates due to the soaring dust adhering to the processing object and the airflow after the collision is outside the furnace. The area by the air flow curtain Cb by increasing the blown air velocity and the air flow rate of the air flow fb at the air outlet for forming the air flow curtain (particularly the side air outlet 5) while avoiding an increase in the amount of heat taken out of the furnace due to the outflow to the furnace The shielding effect can be further enhanced.

  For these reasons, according to the fifth feature, the high temperature gas in the furnace is leaked out of the furnace through the furnace body opening, and the room temperature air outside the furnace enters the furnace through the furnace body opening. Thus, heat loss through the furnace body opening can be more effectively reduced.

The sixth feature configuration of the present invention specifies an embodiment suitable for the implementation of the fifth feature configuration.
The windbreak weir is provided in a state of projecting from the gap area to the object passage area within a range that does not hinder the movement of the object to be processed at the opening of the furnace body.

  According to this structure (refer FIG. 12), not only the airflow part which collides with the floor | bed FL of each gap | interval area | region 2b in the furnace body opening part 2 among the airflow fb blown out from each of the right and left side blower outlets 5. The windbreak weirs 12a and 12b can be made to function on the airflow portion that collides with the floor FL of the object passage area 2a in the furnace body opening 2 due to the expansion in the flow process. The heat loss through 2 can be further effectively reduced.

The seventh characteristic configuration of the present invention specifies an embodiment suitable for the implementation of any of the first to sixth characteristic configurations,
The wind shield weir is a movable weir that can be switched between a wind shield posture that resists airflow flowing in the direction of the object to be processed and a retracted posture that is retracted from the wind shield posture.

  That is, since the windbreak weir is provided on the floor of the furnace body opening in a posture that is resistant to the airflow flowing in the process object passing direction, the work in the process object passing direction (that is, the inside / outside direction of the furnace) is performed. Windbreak weirs are likely to be a hindrance for drying furnace maintenance work and the like that require movement of a person or maintenance equipment.

  On the other hand, according to the above configuration, the windbreak weir, which is a movable weir, can be switched from the windbreak posture to the retracted posture to prevent the windbreak weir from hindering the drying furnace maintenance work and the like. it can.

Side view cross-sectional view of furnace body opening in paint drying furnace II-II arrow view in FIG. III-III arrow view in FIG. Side view showing airflow condition when object is absent Front view showing the air flow when the object is absent Side view showing the airflow state when an object is present Front view showing the airflow state when an object is present Graph showing the correlation between the air outlet angle at the central outlet and the amount of heat loss A graph showing the correlation between the air outlet angle at the side outlet and the amount of heat loss Graph showing the correlation between the air outlet separation distance and the amount of heat loss Enlarged side view showing the collision point of the airflow curtain on the floor in the gap area Front view of windbreak weir Top view of windbreak weir Graph showing correlation between windbreak weir spacing and heat loss Graph showing the correlation between the relative position of the windbreak weir relative to the airflow curtain and the amount of heat loss Side view explaining a state in which the relative positional relationship of the windbreak weir to the airflow curtain is changed A graph showing the relationship between the blown wind speed and the blown air volume for a given floor wind speed Graph showing heat loss reduction effect by shielding weir Circuit diagram showing first example of heating method Circuit diagram showing second example of heating method Circuit diagram showing third example of heating method Front view of furnace body opening showing another embodiment XX arrow view in FIG. Side view explaining scattering of airflow by collision with floor Side view showing leakage of hot gas inside the furnace and penetration of ambient air outside the furnace Perspective view showing another type of paint drying furnace

  1 to 3 show a furnace body opening 2 located at an end portion in the longitudinal direction of a tunnel-shaped furnace body 1 in a paint drying furnace, and this furnace body opening 2 is an entrance to the tunnel-shaped furnace body 1. It is provided at each of the side end and the outlet side end.

  That is, the processing object B (the automobile body in this example) that has undergone the coating process is carried into the furnace through the furnace body opening 2 on the inlet side and subjected to a coating film drying process in a high temperature atmosphere in the furnace, The processed object B that has been subjected to the coating film drying process in the furnace is carried out of the furnace through the furnace body opening 2 on the outlet side.

  In addition, since both the inlet-side and outlet-side furnace body openings 2 adopt the same structure to prevent leakage of the in-furnace hot gas G and intrusion of the outside room temperature air O, in the following, The furnace opening 2 will be described without any distinction between the inlet side and the outlet side, unless otherwise specified.

  By the way, in the furnace body opening 2, as schematically shown in FIG. 25, the high temperature gas G in the furnace leaks out of the furnace through the upper region in the furnace body opening 2 by the drafting action, and is accompanied by this leakage. Then, the room temperature air O outside the furnace enters the furnace through the lower area of the furnace body opening 2.

  The leakage of the in-furnace high temperature gas G and the penetration of the outside room temperature air O through these furnace body openings 2 cause a large heat loss in the paint drying furnace.

  On the other hand, at the edge outside the furnace in the ceiling portion 3 of the furnace body opening 2, a central air outlet arranged at the left and right central part in the lateral width direction of the furnace body opening 2 as an air outlet for forming an airflow curtain 4 and the side blower outlet 5 arrange | positioned on both right and left sides of the central blower outlet 4 are provided.

  The airflow fa blown out from the central outlet 4 forms an airflow curtain Ca in the left and right center object passage area 2a in the furnace body opening 2, and the airflow fb blown out from each of the left and right side outlets 5 is The airflow curtain Cb is formed separately in each gap area 2b between each side wall 6 and the object passage area 2a in the furnace body opening 2.

  That is, by the airflow curtain Ca formed in these object passage areas 2a and the airflow curtain Cb formed in each gap area 2b, leakage of the in-furnace hot gas G to the outside of the furnace through the furnace body opening 2 and Intrusion of the outside room air O into the furnace is prevented.

  The central outlet 4 is formed so as to blow the air current fa toward the furnace inside with a small inclination angle θa with respect to the horizontal (for example, θa <40 °) toward the inside of the furnace, while the left and right side outlets 5 are respectively The inclination angle θb with respect to the horizontal is large (for example, θb> 60 °), and the airflow fb is blown out obliquely downward toward the inside of the furnace.

  That is, by using such a blower outlet structure, in a situation where the processing object B is present in the object passage area 2a of the furnace body opening 2, the blowout from the central blower outlet 4 as shown in FIGS. The airflow fa thus produced has a small inclination angle θa with respect to the horizontal and a large incident angle θin (= 90−θa) with respect to the upper surface portion of the processing object B (in this example, the roof portion of the automobile body). The object B is in a state of flowing smoothly along the upper surface part, and rebounding due to the collision of the processing object B with the upper surface part is suppressed, so that the processing object B is blown out from the central outlet 4 above the processing object B. The airflow curtain Ca without turbulence is stably formed by the airflow fa.

  Therefore, when the processing object B is present in the object passage area 2 a of the furnace body opening 2, leakage of the high temperature gas G in the furnace through the upper area of the furnace body opening 2 to the outside of the furnace is caused from the central outlet 4. The airflow curtain Ca formed above the processing object B by the blown airflow fa and the airflow curtain Cb formed by the airflow fb blown from the left and right side air outlets 5 in the left and right gap regions 2b are more effective. To be prevented.

  Further, since the airflow fb blown out from the left and right side air outlets 5 is inclined downward with a large inclination angle θb with respect to the horizontal, an airflow curtain Cb is formed in each gap area 2b to form a floor in each gap area 2b. After reaching FL, a part thereof is effectively sneak down below the object to be processed B. Under the condition that the object sneaks below the object to be processed B by the sneak current fb ′ below the object to be processed B. Intrusion of room temperature outside air O outside the furnace into the inside of the furnace is prevented.

  Therefore, when the processing object B is present in the object passage area 2a of the furnace body opening 2, the intrusion of the room temperature outside air O through the lower area of the furnace body opening 2 into the furnace is caused by the left and right side blows. The airflow curtain Cb formed by the airflow fb blown out from the outlet 5 in each gap area 2b and the wraparound airflow fb 'that wraps below the processing object B after reaching the floor FL of each gap area 2b are more effective. Is prevented.

  On the other hand, in the situation where there is no processing object B in the object passage area 2a in the furnace body opening 2, as shown in FIG. 4 and FIG. The air flow fa blown from the outlet 4 extends obliquely downward due to the absence of the processing object B to form the air flow curtain Ca in the object passing area 2a, and the processing object B is formed along with the formation of the air flow curtain Ca. Due to the absence of the above, it also extends to each gap region 2b in the lateral width direction of the furnace body opening 2.

  Further, the airflow fb blown from the left and right side outlets 5 toward the inside of the furnace obliquely downward with a large inclination angle θb with respect to the horizontal forms an airflow curtain Cb in each gap region 2b, and the airflow curtain Cb Along with the formation, due to the absence of the processing object B, the airflow curtain fa formed by the blowout airflow fa from the central air outlet 4 extends outside the airflow curtain Ca and extends to the object passage area 2a in the lateral width direction of the furnace body opening 2. .

  Therefore, when the processing object B is not present in the object passage area 2a in the furnace body opening 2, the airflow curtains Ca and Cb can be made nearly double in the furnace body opening 2, and this can be achieved. This effectively prevents leakage of the in-furnace high temperature gas G through the upper region of the furnace body opening 2 and intrusion of the outside room temperature air O through the lower region of the furnace body opening 2.

  8 to 10, respectively, in the furnace body opening 2 having a lateral width W = 2700 mm, a height H = 2750 mm, and a length L = 5000 mm, the central outlet 4 has a lateral side length w = 1800 mm and a longitudinal side length d = 50 mm. The simulation result obtained when each side blower outlet 5 is formed in a slit-like opening having a lateral side length w = 450 mm and a longitudinal side length d = 50 mm is shown.

  The graph of FIG. 8 shows the inclination angle θa and the opening loss ΔR per unit (the amount of heat loss per unit time, unit area, and unit temperature through the furnace body opening 2) when the inclination angle θb is fixed. 9 shows the correlation between the inclination angle θb and the opening loss ΔR per unit in the state where the inclination angle θa is fixed, and the graph of FIG. The correlation with the separation distance x of both the blower outlets 4 and 5 and the opening loss (DELTA) R per unit in the to-be-processed object passage direction at the time of arrange | positioning inside a furnace from the partial blower outlet 5 is shown.

  That is, from these simulation results, in the furnace body opening 2 having a lateral width W = 2700 mm, a height H = 2750 mm, and a length L = 5000 mm, the central outlet 4 has a lateral side length w = 1800 mm and a longitudinal side length d = 50 mm. In addition, in the case where each side outlet 5 is formed in a slit-like opening having a lateral side length w = 450 mm and a longitudinal side length d = 50 mm, in order to reduce heat loss as much as possible, It is desirable to adopt the following specifications for each of the central outlet 4 and the side outlet 5.

    Inclination angle θa ≒ 35 °, Inclination angle θb ≒ 80 °, Separation distance x ≒ 250mm

  In addition, each of the center blower outlet 4 and each side part blower outlet 5 is not restricted to what consists of a non-divided single opening, You may make it consist of a collection of a some division | segmentation opening.

  On the other hand, among the side walls 6 of the furnace body opening 2, the region 2c inside the furnace from the location where the airflow curtains Ca and Cb are formed in the furnace body opening 2 (in short, the inside of the furnace in the furnace body opening 2). An exhaust port 7 for discharging the gas in the in-furnace region 2c to the outside is provided at a portion facing the region.

  That is, because the air flows fa and fb blown from the central outlet 4 and the side outlet 5 are blown into the furnace inner area 2c, the gas in the furnace inner area 2c diffuses into the furnace inside. Mixing with the high-temperature gas G in the furnace is prevented by discharging the gas from these exhaust ports 7, so that the temperature in the furnace is more stably maintained at a temperature suitable for the coating film drying process. .

  In addition, on the floor FL of each of the left and right gap areas 2b in the furnace body opening 2 (see FIGS. 1, 4 and 6), the passing direction of the processing object B on the floor FL (that is, the inside / outside direction of the furnace) ) Is provided with vertical plate-like windbreak weirs 12a and 12b that resist the airflow flowing through

  As shown in FIG. 11, the windbreak weirs 12a and 12b are colliding points t of the airflow curtain Cb on the floor FL in each gap region 2b (that is, the colliding points of the airflow fb blown out from the side outlet 5). The airflow curtain Cb formed in each gap region 2b is arranged in a portion ta adjacent to the outside of the furnace ta and a portion tb near the inside of the furnace, and the windbreak weir 12a outside the furnace and the windbreak inside the furnace The floor FL is caused to collide with the weir 12b.

  That is, when the blowout air speed and the blowout airflow amount of the airflow fb at the side air outlet 5 are increased, the area shielding effect itself by the airflow curtain Cb is increased. However, as shown in FIG. Following the formation of the curtain Cb, it collides with the floor FL in the gap area 2b in a vigorous state and is scattered widely around.

  The scattering of the impinging airflow fb makes the dust soar at the furnace body opening 2 violently, so that the processing quality is likely to deteriorate due to the soaring dust adhering to the processing object B, and the furnace The amount of airflow fb ″ after the collision that flows out to the outside also increases, and the amount of heat taken out to the outside of the furnace increases due to the increase in the amount of outflow air, thereby limiting the effect of reducing heat loss due to the formation of the airflow curtains Ca and Cb. End up.

  On the other hand, by providing the above-described windbreak weirs 12a and 12b on the furnace outer side and the furnace inner side, as shown in FIG. 11, out of the scattering of the airflow fb generated by the collision of the airflow curtain Cb with the floor FL, the processing object Scattering of the airflow fb in the passing direction is effectively suppressed by the resistance (that is, windbreak) by the windbreak weirs 12a and 12b.

  Therefore, as much as the airflow scattering is suppressed, the processing quality is prevented from deteriorating due to the flying dust adhering to the processing object B, and the amount of heat taken out outside the furnace due to the outflow of the airflow fb ″ after the collision to the outside of the furnace is avoided. However, it is possible to further increase the area shielding effect by the airflow curtain Cb by increasing the blowout air velocity and the blowout airflow of the airflow fb at the side air outlet 5, and thereby, through the furnace body opening 2 of the high-temperature gas G in the furnace. In addition, it is possible to more reliably prevent leakage to the outside of the furnace and intrusion of the outside room temperature air O into the furnace through the furnace body opening 2.

  As shown in FIG. 12, each of the windbreak weirs 12a and 12b protrudes from each gap area 2b to the object passage area 2a within a range that does not hinder the movement of the treatment object B in the object passage area 2a. As a result, of the air flow fb blown out from the left and right side air outlets 5, not only the air flow portion that collides with the floor FL of each gap area 2 b but also the spread in the flow process. The windbreak weirs 12a and 12b also suppress the scattering of the airflow in the same manner as described above for the airflow portion that collides with the floor FL of the object passage area 2a.

  And since each wind-shielding weir 12a, 12b is a vertical attitude | position perpendicular | vertical with respect to the to-be-processed object passage direction, after the airflow curtain Cb formed in the gap area 2b reaches the floor FL of each gap area 2b Further, the above-described sneak current fb ′ formed by wrapping under the processing object B is also promoted, and thereby, the in-furnace room-temperature air O entering the furnace inside in a state of diving under the processing object B can be prevented. More effectively prevented.

  Further, as shown in FIG. 13, each of the vertical plate-like windbreak weirs 12 a and 12 b flows on the floor FL in the direction to pass the processing object by rotating around the vertical axis p on the side wall 6 side. The movable weir is switchable between a wind-shielding posture ss that resists airflow and a retracted posture os that retreats from the wind-shielding posture ss and is in a state along each side wall 6.

  Therefore, when performing maintenance work or the like, the necessary work can be performed without interfering with each wind shield weir 12a, 12b by switching each wind shield weir 12a, 12b from the wind shield posture ss to the retracted posture os. It can be performed.

  FIG. 14 shows a state between the windbreak weir 12a outside the furnace and the windbreak weir 12b inside the furnace in a state where the blowout conditions of the air flows fa and fb in the central blowout port 4 and the side blowout ports 5 are fixed. The change in the opening loss ΔR per unit when the interval dimension e is changed is shown. As can be seen from the simulation results, the opening loss ΔR per unit in the case of the above specifications of the furnace body opening 2 and the outlets 4 and 5. Is preferably about 900 mm (e = 900 mm) as the gap dimension e.

  Further, FIG. 15 shows that the windbreak weir 12a outside the furnace and the windbreak weir 12b inside the furnace are in a state where the blowout conditions of the air flows fa and fb at the central blowout 4 and the side blowouts 5 are fixed. Opening loss per unit when the relative positional relationship in the processing object passing direction between the central position between the two and the airflow curtain Cb in the gap region 2b is changed to the three types of positional relationships K1 to K3 shown in FIG. In order to reduce the opening loss ΔR per unit as shown by the change of ΔR and the simulation result, the central position t ′ in the object passing direction between the upper ends of the windbreak weirs 12a and 12b is set to the airflow curtain. Desirably, the windbreak weirs 12a and 12b are arranged in a positional relationship where the formed airflow fb of Cb passes.

  Furthermore, in FIG. 17, the point N is the floor wind speed vF in the direction of the object to be processed in the vicinity of the furnace outer end in the gap region 2b when the windbreak weirs 12a and 12b are not provided as shown in FIG. The blown air velocity vb and the blown air flow rate qb of the air flow fb at the side air outlet 5 that can be maintained at a predetermined wind speed (vF = 1.8 m / s in this example) are shown. When the wind weirs 12a and 12b are arranged in the positional relationship K1 with the spacing dimension e = 900 mm, the floor wind speed vF in the direction of the object to be processed in the vicinity of the outer end of the furnace in the gap region 2b is set to the same predetermined wind speed. The blown air velocity vb and the blown air amount qb of the air flow fb at the side air outlet 5 that can be maintained at (vF = 1.8 m / s) are shown.

  As can be seen from the comparison between the point N and the point M in FIG. 17, by providing the windbreak weirs 12a and 12b, the wind speed vF on the floor in the direction of the object to be treated (that is, due to the airflow collision with the floor FL) The wind speed of the airflow flowing in the direction to pass the object to be processed) can be effectively suppressed, and the floor wind speed vF in the direction to pass the object to be processed in the vicinity of the outer end of the furnace in the gap region 2b is reduced to the same extent. However, the area | region shielding effect of the airflow curtain Cb formed in each gap | interval area | region 2b can be heightened by enlarging the blowing air speed vb and the blowing air quantity qb of the airflow fb in the side part outlet 5.

  And by this, compared with the case where the windbreak weirs 12a and 12b are not provided, the opening loss ΔR per unit can be more effectively reduced by providing the windbreak weirs 12a and 12b as shown in FIG. it can.

  On the other hand, for the air flows fa and fb blown from the central blower outlet 4 and the side blower outlet 5, respectively, the air flows fa and fb heated to a set temperature by appropriate heating means are the central blower outlet 4 and the side blower outlet. 5, so that condensation of the spear component at the furnace body opening 2 is prevented.

  19 to 21 show first to third examples of the airflow heating method. In each figure, 2A is a furnace body opening on the inlet side, 2B is a furnace body opening on the outlet side, and 1A is in the furnace. A temperature raising zone on the inlet side, 1B is a heat retaining zone on the outlet side in the furnace.

  In the temperature raising zone 1A, the processing object B carried into the furnace is heated to a temperature suitable for the coating film drying process by heating in the zone, while in the heat retaining zone 1B, the temperature is raised in the temperature raising zone 1A. The treated object B is maintained at a temperature suitable for the coating film drying process by heating in the zone.

  In any of the first to third examples shown in FIGS. 19 to 21, basically, the high-temperature exhaust gas Ge discharged from the furnace by the exhaust fan Fe is purified by the regenerative gas processing device RTO, and the heat storage The high-temperature exhaust gas Ge purified by the gas type gas processing apparatus RTO is exhausted to the outside after being recovered by heat exchange with the fresh outside air OA in the exhaust gas heat exchanger Ex.

  Further, for each of the temperature raising zone 1A and the heat retaining zone 1B, the high-temperature gases Ga and Gb in the zone are circulated through the circulation paths 8a and 8b by the operation of the circulation fans Fa and Fb. By being heated by the heating furnaces 9a and 9b in the middle of the circulation paths 8a and 8b, the in-zone temperatures are maintained at predetermined temperatures for each of the temperature raising zone 1A and the temperature keeping zone 1B.

  Further, the exhaust gas from the exhaust port 7 provided in the in-furnace region 2c in the furnace opening 2A on the inlet side is combined with the high-temperature gas Ga taken out from the temperature raising zone 1A to the circulation path 8a and heated. Similarly, the exhaust gas from the exhaust port 7 provided in the in-furnace region 2c in the furnace opening 2B on the outlet side is introduced into the furnace 9a, and the high temperature gas Gb taken out from the heat retention zone 1B to the circulation path 8b. Combine and guide to heating furnace 9b.

  In contrast to these common basic configurations, in the first example shown in FIG. 19, the circulating hot gas Ga that has passed through the heating furnace 9a and the circulation fan Fa in the circulation path 8a on the temperature raising zone 1A side (that is, returned to the temperature raising zone 1A). A part of the circulating high-temperature gas Ga) in the stage is supplied to the central outlet 4 and the side outlet 5 in the furnace opening 2A on the inlet side as heated airflows fa and fb blown out from the outlets 4 and 5. Is done.

  Similarly, a part of the circulating hot gas Gb that has passed through the heating furnace 9b and the circulating fan Fb in the circulation path 8b on the heat retaining zone 1B side (that is, the circulating hot gas Gb in the stage of returning to the heat retaining zone 1B) is The heated airflow fa and fb blown out from the blowout ports 4 and 5 are supplied to the central blowout port 4 and the side blowout port 5 in the furnace body opening 2B.

  In this first example, fresh outside air OA that has been heat-recovered by heat exchange with the high-temperature exhaust gas Ge in the exhaust gas heat exchanger Ex is further heated by the burner 10, and then in the heating furnace 9b on the heat retention zone 1B side. It is supplied to the heating furnace 9b on the heat retaining zone 1B side as combustion air for the heating burner.

  On the other hand, in the second example shown in FIG. 20, fresh outside air OA that has been heat-recovered by heat exchange with the high-temperature exhaust gas Ge in the exhaust gas heat exchanger Ex is supplied to the furnace body openings 2A and 2B on the inlet side and the outlet side, respectively. Heated airflow fa and fb blown out from the central blower outlet 4 and the side blower outlet 5 are supplied to the inlets 4 and 5 on the inlet side and the outlet side, respectively, by the feed fan Fs.

  Further, in the third example shown in FIG. 21, as a compromise between the first example and the second example, fresh burned air OA that is heat-recovered by heat exchange with the high-temperature exhaust gas Ge in the exhaust gas heat exchanger Ex is further added by the burner 10. A part of the burner heating outside air OA is supplied to the heating furnace 9b on the heat retaining zone 1B as combustion air of the heating burner in the heat furnace 9b on the heat retaining zone 1B, and the burner heating The remainder of the outside air OA is heated by the supply fan Fs as the heated airflows fa and fb blown from the central outlet 4 and the side outlet 5 in the furnace opening 2A and 2B on the inlet side and the outlet side, respectively. And the outlets 4 and 5 on the outlet side.

[Another embodiment]
Next, other embodiments of the present invention will be listed.

  In the above-described embodiment, the example in which the windbreak weirs 12a and 12b are provided on the outside of the furnace and the neighboring locations ta and tb inside the furnace with respect to the collision point t of the airflow curtain Cb on the floor FL has been described. Alternatively, a windbreak weir may be provided only in one of the neighboring locations ta and tb, or a windbreak weir may be provided at the collision location t of the airflow curtain Cb.

The windbreak weirs 12a and 12b are not limited to the vertical plate shape as described above. For example, the cross-sectional shape may be a levee shape having a trapezoidal shape or a rectangular shape, and the passage of the processing object B on the floor FL. The windbreak weir may have any structure as long as it has a resistance to the airflow flowing in the direction.
In addition, the windbreak weirs 12a and 12b have a structure that can prevent the airflow that has received the resistance from becoming an ascending airflow as it becomes resistance to the airflow flowing in the passing direction of the processing object B on the floor FL If it is more preferable.

  As for the exhaust port 7 for discharging the in-region air from the in-furnace region 2c of the furnace body opening 2, as shown in FIGS. 22 and 23, the furnace body opening in the wall forming the exhaust chamber 11 disposed in the furnace is shown. You may make it provide the exhaust port 7 in the part which faces the in-furnace area | region 2c of the part 2. FIG.

  The exhaust chamber 11 is a chamber for taking out the in-zone hot gases Ga and Gb circulated through the circulation paths 8a and 8b from the zones 1A and 1B in the furnace.

  In the above-described embodiment, the example in which the automobile body that has undergone the painting process is the processing object B has been shown. However, in the present invention, the processing object B is not limited to the automobile body, but an automobile part such as a bumper, Any device casing, building material, railway vehicle, etc. may be used as long as the coating film needs to be dried.

  Further, the present invention is not limited to both the furnace opening 2 (2A) on the inlet side and the furnace opening 2 (2B) on the outlet side in the tunnel-shaped furnace body 1, and either one of the furnaces is used. The present invention may be applied only to the body opening 2.

  The coating drying furnace according to the present invention can be used for coating film drying treatment of various articles in various fields.

B Object to be treated 2 Furnace opening 3 Ceiling 5 Air outlet for forming air curtain, side air outlet fb Air current Cb Air current curtain G High temperature gas in furnace A Outside room temperature air 12a, 12b Wind shield weir FL Floor t Collision Location ta Location near the outside of the furnace tb Location near the inside of the furnace e Interval size 4 Central outlet fa Air flow Ca Air flow curtain 2a Object passage area 6 Side wall 2b Gap area θa, θb Inclination angle ss Wind shielding posture os Retreat posture

Claims (7)

An air outlet for forming an airflow curtain is provided at the ceiling of the furnace body opening through which the processing object to be carried into the furnace from the outside of the furnace or the processed processing object to be carried out of the furnace to the outside of the furnace passes. ,
Due to the airflow curtain formed by the airflow blown from the blowout opening at the furnace body opening, leakage of the high temperature gas in the furnace to the outside of the furnace through the furnace body opening, and the furnace body opening of the outside room temperature air A coating and drying furnace that is prevented from entering the furnace through the section,
On the floor of the furnace body opening, a windbreak weir is provided that resists airflow flowing in the direction of passage of the object to be processed.
The coating-drying furnace in which the windbreak weir is disposed on the floor of the furnace body opening at the collision location of the airflow curtain on the floor of the furnace body opening or in the vicinity of the collision location in the direction of the object to be processed. .   The paint drying furnace according to claim 1, wherein the windbreak weir is provided on the floor of the furnace body opening at each of the vicinity location outside the furnace with respect to the collision location and the vicinity location inside the furnace.   The distance between the wind shield weirs provided at the vicinity of the outside of the furnace with respect to the collision and the vicinity of the inside of the furnace is a correlation between the distance and the amount of heat loss through the furnace body opening. The coating drying furnace according to claim 2, wherein the distance is such that the amount of heat loss through the furnace body opening is minimized.   The relative positional relationship in the processing object passage direction between the airflow curtain and the center position between the wind shield weirs provided at the vicinity location outside the furnace and the vicinity location inside the furnace with respect to the collision location, The paint drying furnace according to claim 2 or 3, wherein the relative positional relationship is a relative positional relationship in which the amount of heat loss through the furnace body opening is minimized in the correlation between the relative positional relationship and the amount of heat loss through the furnace body opening. . As the outlet, a central outlet that forms the airflow curtain in the object passage area in the furnace body opening, and each gap area between the left and right sidewalls in the furnace body opening and the object passage area Left and right side air outlets for forming the air flow curtain separately,
From the central outlet, an airflow for forming an airflow curtain is blown out toward the furnace inside obliquely downward with a small inclination angle with respect to the horizontal,
From each of the left and right side air outlets, an airflow for forming an airflow curtain is blown out toward the furnace inside with a large downward inclination angle with respect to the horizontal, or downward vertically,
The windbreak weir is provided on the floor at a collision location on the floor of the airflow curtain formed by the airflow blown out from the left and right side air outlets or in a vicinity of the collision location in the passing direction of the object to be processed. The coating drying furnace according to any one of claims 1 to 4.   6. The coating drying furnace according to claim 5, wherein the windbreak weir is provided in a state of projecting from the gap area to the object passage area within a range that does not hinder the movement of the object to be treated at the opening of the furnace body. .   The windbreak weir is a movable weir capable of switching between a windbreak posture that resists airflow flowing in the direction of passage of a processing object and a retracted posture that is retracted from the windshield posture. The coating drying furnace according to any one of the above.

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