JP2538089B2 - Body painting method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle body coating method.

2. Description of the Related Art Japanese Patent Application Laid-Open No. 63-1788
As disclosed in Japanese Patent No. 71, the paint is applied to the upper surface and both side surfaces of the vehicle body exposed to the outside of the vehicle, dried, and then baked in an oven. This baking is performed, for example, at 140 ° C. from the air supply duct 2 in the oven 1 as shown in FIG.
By blowing out a certain amount of warm air as indicated by the arrow X, the inside of the oven 1 is formed into a high temperature atmosphere in which the paint can be baked, and the vehicle body W is rotated around the horizontal axis 3 in the direction of the arrow Z in the high temperature atmosphere of the oven 1. While rotating, the paint of the upper surface Wa, both side surfaces Wb, Wc exposed outside the vehicle body W is baked. on the other hand,
The component volatilized in the oven 1 by baking is indicated by the arrow Y.
As shown by, the exhaust duct 4 discharges the gas from the oven 1. Reference numeral 5 in the drawing is a dolly for carrying in the vehicle body W to which the paint has been applied and dried, and a rail 6 for guiding the dolly 5.

Problems to be Solved by the Invention In the above-described conventional method, since the vehicle body W is rotated until the paint is cured in the high temperature atmosphere of the oven 1, the flow surface on the vertical surface is improved, but the flow on the horizontal surface is insufficient. And the skin gets worse.

Therefore, according to the present invention, after coating the upper surface and both side surfaces of a vehicle body with a coating material, the vehicle body is carried into an oven having a flat heater in which the vehicle body is horizontally positioned and the horizontal axis of the vehicle body is set. By rotating around and stopping at the position where the three surfaces face the heater for a predetermined time, baking is performed with the upper surface and both side surfaces of the vehicle body sequentially corresponding to the heater.

Embodiment As shown in FIGS. 1 and 2, in this embodiment, the upper surface Wa of the vehicle body W exposed to the outside of the vehicle and the side surfaces Wb, Wc are, for example, 80 ° C.
After coating a coating material mixed with a flow agent so that the viscosity is reduced and dried, the vehicle body W is carried into the oven 11 by the dolly 10. The dolly 10 includes a carriage 12 as shown in FIG. The dolly 12 is adapted to travel on wheels 15 on rails 14 laid on the floor of the installation inside the oven 11 by the power transmitted from a drive chain 13 as a transport drive mechanism. Horizontal shafts 18 and 19 for holding the front and rear portions of the vehicle body W between the front and rear portions of the vehicle body 12 are mounted on the upper portions of the front and rear columns 16 and 17 of the carriage 12 so as to be rotatable. A rotary drive mechanism 20 is connected to the front horizontal shaft 18. The rotary drive mechanism 20 includes a rack gear 21, a pinion gear 22, and bevel gears 23 and 24. Rack gear 2
1 is laid so as to be movable along a rail 14. The pinion gear 22 is a shaft 25 rotatably mounted on the bogie 12
Is coupled to a lower end protruding downward from the truck 12 and meshes with a rack gear 21. One bevel gear 23 of the bevel gears 23, 24 is coupled to the upper end of the shaft 25 protruding above the carriage 12. The other bevel gear 24 that meshes with the bevel gear 23 is coupled to the intermediate portion of the horizontal shaft 18. Then, the vehicle body W carried into the oven 11 by the dolly 10 is rotated about the horizontal shaft 18 by the rotary drive mechanism 20. By being stopped, the upper surface Wa and both side surfaces Wb, Wc of the vehicle body W are sequentially corresponded to the far-infrared heater 30 as a heater horizontally installed on the ceiling in the oven 11, and baking is performed. Specifically, as shown in FIG. 1, first, the drive chain 13 and the rack gear 21 move at a constant speed with the upper surface Wa of the vehicle body W facing upward, so that the vehicle body W is moved inside the oven 11. When the upper surface Wa of the vehicle body W corresponds to the far infrared heater 30, the drive tune 13 and the rack gear 21 are stopped for 5 minutes, for example. As a result, the paint applied and dried on the upper surface Wa while the upper surface Wa of the vehicle body W corresponds to the far-infrared heater 30 is baked for 5 minutes at an ambient temperature of 140 ° C., for example.

Next, the rack gear 21 is moved at a speed higher than that of the drive tune 13, for example, for 1 minute. That is, the rotary drive mechanism 20
The vehicle body W is rotated about 90 degrees around the horizontal axes 18 and 19 by the rack gear 21, the drive chain 13 and the side surface Wb of either side Wb or Wc of the vehicle body W corresponding to the far infrared heater 30. And are stopped for 5 minutes, for example. As a result, the coating material applied and dried on the side surface Wb is baked for 5 minutes at an ambient temperature of 140 ° C., for example.

Further, the rack gear 21 is moved at a faster speed than the drive chain 13, for example, for 1 minute to rotate the vehicle body W about the horizontal axes 18 and 19 in the same direction as above by about 180 °, and the other side surface Wc of the vehicle body W is moved. At a position corresponding to the far infrared heater 30, the rack gear 21 and the drive chain 13 are stopped, for example, for 5 minutes. As a result, the coating material applied and dried on the side surface Wc is baked for 5 minutes at an ambient temperature of 140 ° C., for example.

Thereafter, the rack gear 21 is moved at a speed faster than that of the drive chain 13, for example, for 1 minute to rotate the vehicle body W about the horizontal axes 18 and 19 in the same direction as above by about 90 °, and the upper surface Wa of the vehicle body W is raised. The vehicle body W is carried out of the oven 11 while moving the rack gear 21 and the drive chain 13 at a constant speed.

Here, regarding the viscosity of the paint applied to the vehicle body W,
It will be described in detail with reference to the drawings. First, the viscosity of the paint increases between the time when the paint is applied to the vehicle body W and the time when it is dried, that is, during the setting time. Next, during the baking time in the oven 11, the upper surface Wa of the vehicle body W, both side surfaces Wb, Wc
Immediately after individually corresponding to the far-infrared heater 30, the viscosity of the coating material sharply decreases, the coating material enters a flow state and becomes smooth, and then gradually rises to be cured and the baking is completed.
Far-infrared heater of the vehicle body W during this baking
The surface that does not directly correspond to 30 does not have the above flow phenomenon and curing phenomenon because the temperature does not rise up to around 80 ° C.

Incidentally, the present invention is not limited to the above embodiment, as shown in FIGS. 5 and 6, the rail 14A is laid in a spiral manner in the oven 11, and the coating material is applied by the transport drive mechanism 13A.
By rotating and moving the dolly 12A having the dried vehicle body W along the rails 14A, the upper surface Wa, both side surfaces Wb, Wc of the vehicle body W can be printed in a state of being sequentially associated with the far infrared heater 30. . In this case, since the vehicle body W can be rotated only by the transport power without providing the rotation drive mechanism, there is an advantage that the structure of the device can be simplified.

EFFECTS OF THE INVENTION As described above, according to the present invention, since only the surface corresponding to the heater can be baked without heating the surfaces other than the surface corresponding to the heater horizontally provided in the oven of the vehicle body, On the leveled surface, the phenomenon of decrease in viscosity, flow, and curing of the coating material is caused, so that a coating film with good skin and good appearance performance can be obtained.

[Brief description of drawings]

1 is an explanatory view showing the operation of an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, FIG. 3 is a side view of a dolly used in the same embodiment, and FIG. FIG. 5 is a characteristic diagram showing the relationship between the viscosity of the paint of the same example and the treatment time, FIG. 5 is a side view showing a part of another example of the present invention, and FIG. 6 is a line VI-VI in FIG. FIG. 7 is a vertical sectional view of a conventional oven. 11 …… oven, 30 …… heater (far infrared heater), W
…… Car body, Wa …… top surface, Wb, Wc …… side surface.

Claims (1)

(57) [Claims] 1. After applying paint to the upper surface and both side surfaces of the vehicle body,
The vehicle body is loaded into an oven having a flat heater positioned horizontally, rotated about the horizontal axis of the vehicle body, and stopped for a predetermined time at the positions where the three surfaces face the heater. A method of painting a vehicle body, characterized in that baking is performed with the upper surface and both side surfaces sequentially corresponding to the heater.