JP5665395B2 - Paint remaining amount measuring device in powder coating equipment - Google Patents

Description

  The present invention relates to a paint remaining amount measuring device in a powder coating apparatus that sucks powder paint from a powder paint tank and supplies it to a powder coating gun.

  2. Description of the Related Art Conventionally, a powder coating apparatus includes an injector that sucks powder paint from a powder paint tank and carries the powder paint to the powder coating gun by air from a discharge port via a transport hose.

  The injector has a main air nozzle connected to a compressed air source via a flow restrictor, and the main air supplied from the main air nozzle generates a negative pressure in the injector body. This is a device that sucks powder from a paint tank and discharges powder paint from a discharge port together with main air.

  By the way, the powder coating material discharged from the injector body is transported into the transport hose by the main air. In order to supply stable transport air into the transport hose, a flow restrictor is provided in the injector and a compressed air source. In general, a sub air nozzle that is connected via the main air is supplied to the transport hose together with the main air (Patent Document 1 and Patent Document 2).

JP 2002-273282 A JP 2006-102708 A

  By the way, in a conventional powder coating apparatus that sucks a powder paint from a powder paint tank and supplies it to a powder coating gun, when the remaining amount of the powder paint in the powder paint tank decreases, the powder paint tank It is necessary to refill new powder or replace the powder coating tank with a new one.

  However, conventionally, in order to know the remaining amount of powder paint in the powder paint tank, the weight of the powder paint tank is measured, or the height of the powder paint in the powder paint tank is measured with a leveler. It is necessary to do.

  In order to measure the remaining amount by such a method, it is necessary to increase the apparatus cost or to perform complicated control.

  Therefore, the present invention is intended to measure the remaining amount of the powder paint in the powder paint tank easily from the operation time of the powder coating apparatus.

In order to solve the above-described problems, the present invention has a main air nozzle connected to a compressed air source via a flow restrictor, and the main air supplied from the main air nozzle causes a powder from the powder coating tank. It is equipped with an injector that sucks body paint from the discharge port and conveys the powder paint to the powder coating gun via the transfer hose, and supplies the sub-air to the injector and is connected to the compressed air source via the flow restrictor. The sub air nozzle is equipped with a flow throttle valve for the main air nozzle and an electronic control device that adjusts the flow throttle valve for the sub air nozzle to keep the amount of powder discharged from the powder coating gun constant. keeping while, in the case of adjusting the total air amount of the transport air supplied to the conveying hose from the injector main supplied from the main air nozzle While maintaining the N'ea amount constant, the adjustment of the total air amount, in order to perform the Sabuea amount supplied from the sub-air nozzle, by the controller, the main air amount supplied from the main air nozzle, the conveying hose from the discharge port Control the amount of sub-air supplied from the sub-air nozzle to the amount obtained by subtracting the main air amount from the set amount of the total air amount supplied to the transfer hose. At the same time, the operating time of the injector is integrated, and the accumulated amount of powder paint is calculated by multiplying the accumulated time by the discharge amount of powder paint per unit time. This is a built-in residual quantity measurement program that subtracts the powder paint cumulative usage and measures the residual quantity of the powder paint tank.

  Then, when the remaining amount of the powder coating tank falls below a previously input value, a warning display or a powder coating replenishment display is performed.

  According to the present invention, the electronic control device for adjusting the flow throttle valve of the main air nozzle and the flow throttle valve of the sub air nozzle has the operating time of the injector and the powder coating material per unit time when the injector is operated. It is possible to calculate the remaining amount of the powder coating tank simply by actually measuring and inputting the discharge amount in advance.

  Therefore, it is possible to measure the remaining amount of powder paint in the powder paint tank easily from the operating time of the powder coating equipment without using a special weighing scale or leveler. Can be planned.

1 is an overall configuration diagram showing an embodiment of a powder coating apparatus according to the present invention.

Embodiments of the present invention will be described below.
FIG. 1 shows a powder conveying device used in a powder coating apparatus for sucking a powder coating A from a fluid type powder coating tank 1 by an injector 2 and air conveying and discharging the powder coating to a coating gun 3. Is shown. Examples of the coating gun 3 include a corona electrostatic coating gun having a corona electrode at the tip of the gun, and a friction charging electrostatic coating gun having a friction tube in the gun body.

  The lower part of the powder coating tank 1 is partitioned by the porous plate 4, and the compressor air 5 dehumidified and deoiled is introduced from below the porous plate 4. The powder coating A in the powder coating tank 1 is dehumidified by the flowing air discharged from the porous plate 4 and dispersed in a fluid state.

  In the upper part of the powder coating tank 1 is installed an injector 2 that sucks the powder coating A in the powder coating tank 1 and air-transports the powder coating A to the coating gun 3 via the transfer hose 6. ing.

  The injector 2 is provided with a main air nozzle 7 and a sub air nozzle 8.

  The main air nozzle 7 and the sub air nozzle 8 are connected to a compressed air source 9 such as a compressor to which compressed air is supplied via flow restrictors 10 and 11, respectively.

  A pressure reducing valve 15 is installed between the compressed air source 9 and the flow restrictors 10 and 11.

  The opening degree of the flow restrictors 10 and 11 is automatically adjusted by the electronic control unit 13.

  The electronic control unit 13 is instructed in advance with the relationship between the opening degree of the flow restrictors 10 and 11, the powder suction amount corresponding to the main air amount of the main air nozzle 7, and the actually measured value of the sub air amount of the sub air nozzle 8. It is entered as a value. Further, the electronic control unit 13 includes an integration means for integrating the operating time of the injector 2 and an accumulated usage amount of the powder paint calculated by multiplying the integration time by the discharge amount of the powder paint A per unit time. A program including a remaining amount measuring means for calculating and measuring the remaining amount of the powder coating tank 1 by subtracting the accumulated amount of the powder coating from the initial charging amount of the powder coating tank 1 is incorporated.

  When the remaining amount of the powder paint tank 1 falls below a value input in advance, a warning display or a replenishment display of the powder paint A is performed.

  The compressed air supplied from the main air nozzle 7 of the injector 2 is called main air. The powder paint A is given a negative pressure to the suction port 12 by the Venturi principle and the powder paint A is passed through the suction pipe 16. Has a function of sucking and transporting to the coating gun 3. Generally, when the pressure and amount of the main air are increased, the venturi effect from the suction port 12 increases, the discharge amount from the discharge port 14 increases, and the amount of powder per unit time from the coating gun 3 increases. Become.

  Next, since the sub air supplied from the sub air nozzle 8 mainly has the length of the transport hose 6 and the resistance thereof depending on the installation location of the paint tank 1 and the arrangement of the gun, the powder paint A passes through the transport hose 6. It is responsible for transporting at a uniform and stable speed.

  At the time of painting, the main air and sub air are supplied from the main air nozzle 7 and the sub air nozzle 8 to the injector 2, and the powder paint A in the paint tank 1 is supplied to the suction pipe 16, the suction port 12, and the discharge port. 14, the powder paint is discharged from the coating gun 3 through the transport hose 6.

The adjustment of the main air and the sub air is performed as follows.
The main air amount (l / min) is set so that the discharge amount (g / min) of the powder coating material A per unit time discharged from the coating gun 3 becomes the target discharge amount.

  The sub air amount (l / min) is set to an amount obtained by subtracting the main air amount from the total air amount set according to the shape of the object to be coated.

  When the total air amount is changed, for example, when the total air amount is reduced to 90 (l / min) and the painting work that has been operated at the total air amount is 100 (l / min), the main air amount is changed. The opening degree of the flow restrictor 11 of the sub air nozzle 8 is adjusted by the electronic control unit 13 so that only the sub air amount is reduced by 10 (l / min) without changing the air amount.

  Thus, even if the total air amount is changed, the main air amount is not changed, so that the discharge amount (g / min) of the powder coating material can be kept constant.

  Therefore, by using a relational expression between the main air amount and the paint discharge amount measured in advance, the discharge amount of the powder paint A with respect to the current set value (discharge command value), that is, the discharge amount per unit time ( g / min) can be obtained by calculation, and by multiplying this value by the time during which the main air nozzle 8 is operating, the accumulated usage amount of the powder coating material A can be obtained. Is subtracted from the initial amount of paint in the powder paint tank 1, the remaining amount of the powder paint tank 1 can be easily obtained.

For example, when the discharge amount of the powder coating material A when the injector 2 is operated and sprayed for 30 seconds under the condition that the installation value of the discharge amount is 50 and the set value of the total air amount is 100 is an actual measurement value of 60 g The remaining amount of paint when the setting value of the discharge amount is 40 and it is operated for 50 minutes and the setting value of the discharge amount is 60 and it is operated for 20 minutes is calculated as follows.
The initial amount of the powder paint A in the powder paint tank 1 is 15 kg.
When the installation value of the discharge amount is 100, the discharge amount per second is
(60g / 30sec) × 100/50 = 4g
When the installation value of the discharge amount is 40, the discharge amount per second is
(4g) × 40/100 = 1.6g
When the installation value of the discharge amount is 60, the discharge amount per second is
(4g) × 60/100 = 2.4g
It becomes.

Therefore, the amount of the current powder paint A from 15 kg of the initial powder paint A,
15000 g- (1.6 g × 3000 sec) − (2.4 g × 1200 sec) = 7320 g
become.

DESCRIPTION OF SYMBOLS 1 Powder coating tank 2 Injector 3 Coating gun 4 Porous board 5 Compressor air 6 Conveyance hose 7 Main air nozzle 8 Sub air nozzle 9 Compressed air sources 10 and 11 Flow rate throttle valve 12 Suction port 13 Electronic control unit 14 Ejection port 15 Depressurization Valve 16 Suction tube A Powder paint

Claims (3)

It has a main air nozzle connected to the compressed air source via a flow restrictor, and the main air supplied from this main air nozzle sucks the powder paint from the powder paint tank and passes it from the discharge port through the transport hose. The powder coating gun is equipped with an injector that conveys the powder coating air, and the sub air nozzle connected to the compressed air source via the flow throttle valve is provided to supply the sub air to the injector. And an electronic control device that adjusts the flow throttle valve of the sub air nozzle, and the electronic control device maintains a constant amount of powder per unit time discharged from the powder coating gun, while conveying from the injector when adjusting the total air quantity of conveying air supplied to, the constant main air amount supplied from the main air nozzle Chitsutsu, the adjustment of the total air amount, in order to perform the Sabuea amount supplied from the sub-air nozzle, by the controller, the main air amount supplied from the main air nozzle, which supplies powder to the conveying hose from the discharge port The amount of sub air supplied from the sub air nozzle is controlled to an amount that allows the set discharge amount to be obtained, and the main air amount is subtracted from the set amount of the total air amount supplied to the transfer hose, and the injector is operated. Accumulate time, calculate the total amount of powder paint used by multiplying the accumulated time by the amount of powder paint discharged per unit time, and calculate the total amount of powder paint based on the initial charge in the powder paint tank. Paint residual quantity meter in powder coating equipment, which has a built-in residual quantity measurement program that subtracts the amount and measures the residual quantity of the powder paint tank Apparatus.   2. The paint remaining amount measuring device in the powder coating apparatus according to claim 1, wherein the powder coating gun is an electrostatic coating gun.   3. The paint remaining amount in the powder coating apparatus according to claim 1, wherein when the remaining amount of the powder paint tank falls below a pre-input value, a warning display or a replenishment display of the powder paint is performed. Measuring device.

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