JPS5920362Y2 - clear coating equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a clear coating device for spraying a clear coating onto an object to be coated after metallic coating using an electrostatic coating machine.

In general, the top coat of the object to be painted, such as an automobile body, is applied with either metallic paint or Sonorad paint according to the painting specifications, and the object to be painted after metallic coating is further coated with protection and polishing of the painted surface. A clear paint is being sprayed on it.

Conventionally, when applying clear paint on a mixed painting line where the objects to be painted are sprayed according to each coating specification on one painting line, as shown in Fig. 2,
When painting with metallic paint, the AC voltage of the power supply circuit S is converted to DC voltage by the DC rectifier circuit C, and the DC high voltage obtained by the high voltage generation circuit d is passed through the resistor e to a mini-bell type electrostatic coating machine. At the same time, the clear paint is charged and atomized by the high-speed rotation of the minibell driven by the electrostatic coating machine, and electrostatically coated on the object a.

When object a to be solid coated enters this painting area, if high voltage is kept being supplied even if electrostatic atomizers f and f are stopped, the inside of the minibell of electrostatic atomizer f will be damaged. Due to the attraction of static electricity, the clear paint that stays on the surface of the solid paint adheres to the painted surface in the form of strings and stains the painted surface.
A specification identification piece such as an ear piece is provided on the cart g on which JIIJa is placed, and this specification identification piece is detected by a detection circuit i, and the detection signal causes a short circuit control circuit j to operate, thereby creating a high voltage short circuit k. The circuit is closed, and the high voltage of the high voltage generating circuit d is made conductive to the resistor (2), which has a smaller resistance value than the resistor (e), and is short-circuited and grounded.

However, when the high voltage short circuit k is closed, an overcurrent is instantaneously applied to the high voltage generating circuit d, which reduces the durability of the diodes, capacitors, etc. of the high voltage generating circuit d, and reduces the operating rate of the clear coating equipment. There is a problem with it decreasing.

The present invention has been made in view of such problems, and includes a power supply adjustment circuit interposed between a high voltage generation circuit and a DC rectification circuit, a detection circuit and a control circuit connected to the power supply adjustment circuit,
A detection circuit detects the object to be painted with solid paint, and a control circuit that receives this detection signal reduces the input voltage from the power supply adjustment circuit to the high voltage generation circuit to prevent clear paint from adhering to the object due to static electricity attraction. To provide a clear coating device which increases the input voltage of a high voltage generating circuit to apply clear coating to metallic coated objects.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described in detail below with reference to the drawings.

Reference numeral 1 denotes a clear coating device in which mini-bell type electrostatic coating machines 4 are disposed in a coating mixing line 3 that separates metallic coating and solid coating depending on the object 2 to be coated, such as an automobile body.

The clear coating device 1 is supplied with power (for example, AC 200V) by a power supply circuit 5, and generates a high voltage (for example, 90 KV) to apply a high voltage (for example, 90 KV) between the electrostatic coating machines 4, 4 and the object to be coated 2. a circuit 6, a power supply adjustment circuit 7 such as a power transistor connected to the high voltage generation circuit and the power supply circuit 5, a detection circuit 8 for detecting whether the object 2 to be painted is metallic or solid coating; Depending on the output, the input voltage of the high voltage generation circuit 6 is increased to maintain the output high voltage (for example, 90 KV) when the object is metallic coated, and the input voltage of the high voltage generation circuit 6 is lowered when the object is solid coated. The power supply adjustment circuit 7 is coupled with a control circuit 9 that controls the base voltage of the power supply adjustment circuit 7 so as to regulate the output voltage to, for example, less than 1KV.

10 is connected between the power supply circuit 5 and the power supply adjustment circuit 7, and converts the AC power supply voltage (200V) to the DC voltage (for example, 200V).
5V); 11 is a power supply circuit that supplies power to the control circuit 9; 12 is a DC rectifier circuit that converts the output voltage of the high voltage generation circuit 6 to A high-voltage short-circuit circuit 14 is fixed to a trolley moving on the coating mixing line 3, and 15 is fixed to the trolley 14 on which the object 2 to be coated with solid paint is placed. 1) Body signals such as those of the ear pieces to be linked.

In the above structure, when the object 2 to be coated with metallic paint enters the coating area of the clear coating device 1, the electrostatic coating devices 4, 4 are driven, and the minibell of the coating device rotates at high speed and generates a high voltage. A high voltage (90 KV) is boosted by the circuit 6 and applied between the minibell of the electrostatic coating machines 4 and 4 and the object 2 to be coated.
) After clear coating the object 2 to be coated, the electrostatic coating machines 41 and 4 are stopped, and the object e72 to be coated is carried out from the coating area.

When the subsequent object 2 to be painted is solid painted, the detection circuit 8 detects the signal from the body signal device 15 of the painting specification, and the control circuit 9 controls the power supply adjustment circuit 7 according to the output of the detection circuit. By controlling the base voltage, the input voltage of the high voltage generation circuit 6 is lowered, and the voltage acting between the electrostatic coating machines 4, 4 and the object to be coated 2 is lowered to a relatively low voltage (for example, less than IKv). By doing so, the stopped electrostatic coating machine 4
The clear paint remaining in the mini bell is prevented from being applied to the object to be painted 2 due to the attraction of static electricity, and the object to be painted can pass through the painting area without being soiled.

With the above configuration, when the object to be painted is metallic painted, the present invention uses DC high voltage raised to a predetermined voltage in a high voltage generation circuit and high-speed rotation of an electrostatic coating machine to perform clear coating and solid coating. When the object is painted, the detection circuit detects the body signal indicating the painting specifications, and the control circuit suppresses the base voltage of the power supply adjustment circuit and lowers the input voltage of the high voltage generation circuit, which connects the electrostatic atomizer and the object. It reduces the voltage that acts between the paint and the object and easily prevents abnormal adhesion of clear paint due to static electricity, which greatly improves workability and productivity. It is something that we have.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an electrical circuit connected to a paint mixing line, and similarly, FIG. 2 is a diagram illustrating a conventional example. 1...Clear coating device, 2...Object to be coated, 3...Painting mixing line, 4...Electrostatic coating machine, 5... ...Power supply circuit, 6...High voltage generation circuit, 7...Power supply adjustment circuit, 8...
...Detection circuit, 9...Control circuit.

Claims (1)

[Scope of utility model registration request] An electrostatic coating machine that sprays clear paint onto the objects to be coated after metallic coating is installed in a mixing painting line that separates metallic paint and solid paint depending on the object to be painted. A high voltage generation circuit for applying a high voltage between a nozzle of an electrostatic coating machine and an object to be painted, a power supply adjustment circuit connected between the high voltage generation circuit and the power supply circuit, and an object to be painted. is a detection circuit that detects whether metallic coating is solid coating, and depending on the output of the detection circuit, increases the input voltage of the high voltage generation circuit when the object is metallic coating, and increases the input voltage of the high voltage generation circuit when the object is solid coating. and a control circuit that controls the power supply adjustment circuit so as to reduce the voltage applied between the nozzle of the electrostatic atomizer and the object to be painted when the object to be painted is solid coating. A clear coating device characterized in that the clear coating is prevented from adhering to a solid coated object by the attraction force caused by static electricity.