JP2003305387A - Rotary atomizing type coating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary atomizing type coating machine capable of controlling the fleight of atomized particles by shaping air streams of ultralow pressure to form a good atomizing pattern without obstructing the coating deposition of the atomized particles. <P>SOLUTION: In the bell-shaped rotary atomizing type coating machine, an atomizing pattern forming fan, which is concentric to the rotary shaft of an atomizing rotary bell and has a plurality of blades rotated in connection with a rotary shaft or rotated by other independent drive motor, is arranged behind the rotary bell. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary atomizing type coating machine for controlling the flight of atomized particles by an ultra-low pressure shaping air flow. 2. Description of the Related Art Compressed air (shaping air) for forming a pattern of a bell type rotary atomizing type electrostatic coating machine is as follows.
Normally, as shown in FIG. 2, the air is supplied from a ring-shaped shaping air head 11 arranged so that compressed air is applied to the periphery of the bell head 10. On the ring of the shaping air head 11, pores 12 having a diameter of about 1 mm
Approximately 60 holes are formed, and compressed air is blown out from the holes. This shaping air head 11
The atomized particles 13 that fly out of the bethead 10 in the direction of centrifugal force by the compressed air blown out from the nozzle are forced to travel in the direction of the object to be coated, and are conveyed to the object by the accompanying airflow 14 formed by the shaping air. It is applied to an object to be coated by the combined effect with electrostatic force. However, in a normal shaping mechanism, high-pressure compressed air (approximately 0.2 MPa · s) blows out from the pores, so that a vortex is generated around the bell head due to a pressure difference, and atomized particles are generated. The turbulent air flow in the spray pattern in which the airplane flies is turbulent, and as a result, there are problems such as impeding the application of atomized particles and contaminating the bell head. Further, since the thickness of the layer of the air flow blown out from the shaping air head and supplied around the bell head is about 1 to 2 cm, among the atomized particles, particles having a large particle diameter, for example, large particles containing a large amount of aluminum pigment or Since the aluminum pigment itself has a large centrifugal force (inertia force), it breaks through this air flow layer and scatters, making it impossible to control the pattern and adversely affecting the original color of the formed coating film. It also caused the wearing efficiency to drop significantly. [0004] Further, the shaping air in the rotary atomizing type coating machine consumes a large amount of compressed air, which is problematic in terms of energy. An object of the present invention is to provide a rotary atomizing type coating machine which can generate shaping air without hindering application of atomized particles and can form a good atomized pattern. SUMMARY OF THE INVENTION The present invention is a bell-type rotary atomizing type coating machine, which is concentric with a rotary shaft of a rotary atomizing bell and rotates in conjunction with the rotary shaft. Or a fan for forming an atomization pattern having a plurality of blades rotated by another independent driving motor is disposed behind the rotary bell. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view and a side view around a bell head of a rotary atomizing type coating machine according to an embodiment of the present invention. In FIG. 1, 1 is a bell head, 2 is a fan (rotary blade), 3 is a rotating shaft, 4 is a shaping air flow,
Numeral 5 denotes atomized particles. Behind the bell head 1, a fan 2 for generating a shaping air flow 4 is provided concentrically with a rotating shaft 3 of the bell head 1, and the fan 2 rotates in conjunction with the rotation of the bell head 1. As a result, a shaping air flow 4 having an extremely low pressure and a large air flow is generated, and an atomization pattern is formed in which the atomized particles 5 that fly out of the bell head 1 in the direction of centrifugal force fly toward the object to be coated. The size of the blades of the fan 2 can be changed according to the size of the desired atomization pattern. The fan 2 may be started and rotated by diverting an air motor (not shown) for rotating the bell head 1, or a dedicated motor separate from the bell head 1 may be used. The shaping air flow 4 formed by the fan 2 has an extremely low pressure and the thickness of the air flow can be secured by the length of the blades. Further, even if the bell head 1 and the fan 2 have the same rotation speed, the strength of the shaping air flow 4 can be freely controlled by the shape and the number of blades of the fan 2. Further, when the blade of the fan 2 is made of metal and a high voltage having the same polarity as that of the bell head 1 is applied, the blade becomes an electrode covering the entire atomization pattern, and an electric field effective for electrostatic coating is formed. It is also possible to form. Since the wings of the fan 2 are charged with the same charge as the bell head 1, it is possible to prevent the atomized particles 5 from blowing back and further improve the coating efficiency. According to the rotary atomizing type coating machine of the present invention, the flight of the atomized particles is controlled by the ultra-low pressure shaping air flow, so that the application of the atomized particles is hardly hindered. In addition, a good atomization pattern can be formed, and the change in tint of a metallic coating film or the like can be reduced, and the coating efficiency can be greatly improved. In addition, the turbulence of the atomization pattern is eliminated, the dirt on the bell head and the contamination of the coating machine body are improved, and the compressed air conventionally used for shaping air becomes unnecessary, and the consumption of the compressor air is reduced by about 1%.
/ 3 is also achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view and a side view around a bell head of a rotary atomizing type coating machine according to an embodiment of the present invention. FIG. 2 is a front view and a side view of the periphery of a bell head of a conventional rotary atomizing type coating machine. [Description of Signs] 1, 10 bell head 2 fan (rotor blade), 3 rotating shaft 4 shaping air flow 5, 13 atomized particles 11 shaping air head 12 pores 14 accompanying air flow

Claims (1)

Claims 1. A bell-type rotary atomizing type coating machine, wherein the rotary atomizer is concentric with a rotary shaft of a rotary bell for atomization and rotates in conjunction with the rotary shaft, or other components. A fan for forming an atomization pattern having a plurality of blades which are rotated by independent drive motors, is disposed behind the rotary bell.