JP2016097350A - Powdered paint feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize an amount of a powdered paint A flowing in a paint tank 1 and taken out to reduce the occurrence of paint defects in a powdered paint feeding device provided with take-out devices 5, which causes the powdered paint A in the paint tank 1 to flow and suction the powdered paint A flowing in the paint tank 1, and including a forcible exhaust device 7 in the paint tank 1.SOLUTION: In a powdered paint feeding device, a lower part in a paint tank 1 housing a powdered paint A is divided by a division wall 2 formed by a porous material. The powdered paint feeding device is provided with take-out devices 5, which supply flow air 3 from an area below the division wall 2 to the paint tank 1 to cause the powdered paint A in the paint tank 1 to flow and suction the powdered paint A flowing the paint tank 1, and includes a forcible exhaust device 7 in the paint tank 1. A natural air flow port 9 for regulating an internal pressure in the paint tank 1 to an atmospheric pressure is installed at an upper part of the paint tank 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a powder coating material supply apparatus that sucks a powder coating material from a coating tank that contains the powder coating material in a fluidized state by flowing air and supplies the powder coating material to a coating gun.

  Powder coating does not contain organic solvents, and overspray powder that has not adhered to the object to be coated can be collected and reused, so it has been adopted in many products in recent years as an environmentally friendly coating.

  It started with road materials such as guardrails and fences, and is widely used in products used at home such as refrigerators and air conditioner outdoor units. Recently, it is also used to paint school chairs and desks and license plates.

  In general, powder coating is performed by using a corona gun or a frictional charging gun and spraying a powder coating on an object to be coated.

  In the case of a corona gun, an electric field is generated between the corona electrode at the tip of the gun and the object to be coated, and the powder paint discharged from the gun is attached to the object by corona discharge.

  In addition, the friction charging gun includes a non-conductive resin tube, for example, in the gun, and the powder paint is passed through the non-conductive resin tube to cause friction between the non-conductive resin and the powder paint. Thus, the charged powder coating discharged from the gun tip adheres to the object to be coated by electrostatic force.

  By the way, a fluid-type paint tank has been conventionally used as a paint tank that can draw out a fine powder paint without a lump (Patent Document 1).

  The fluid type paint tank partitions the lower part of the paint tank that contains the powder paint with a partition wall made of a porous material, and supplies the fluid air into the paint tank from the lower part of the partition wall to supply the powder in the paint tank. The paint is allowed to flow.

JP 2008-229544 A

  When supplying powder paint from a fluid paint tank as described above to supply powder paint to a paint gun, insert a pipe with a suction device such as an injector into the paint tank, The powder paint is sucked and the powder paint is supplied to the paint gun.

  In the fluid paint tank, fluid air is supplied from below the partition wall made of porous material. The fluid air eliminates the lump of powder paint and removes moisture from the powder paint. When flowing air is supplied to the tank, the internal pressure in the paint tank rises due to the supply of flowing air.

  For this reason, a drawing pipe provided with a suction device such as an injector is installed on the upper part of the paint tank, and forced exhaust of the flowing air supplied from the drawing pipe to the paint tank is performed.

  However, if the forced exhaust from the extraction pipe is strong, the inside of the paint tank becomes negative pressure, and it becomes difficult to remove the new powder replenishing lid of the paint tank when refilling the paint tank with new powder.

  In addition, when the pressure in the paint tank becomes negative, when the powder paint in the paint tank is pulled out by a pipe equipped with a suction device such as an injector, the amount of powder paint to be sucked in due to the change in the negative pressure in the paint tank Changes. For this reason, the discharge amount from the coating gun also changes, a difference occurs in the film thickness, and the problem of poor coating occurs.

  On the other hand, if the forced exhaust from the extraction pipe is weak, the inside of the paint tank becomes positive pressure, and when refilling the paint tank with new powder, opening the new powder replenishing cover of the paint tank will cause the powder paint to spout. In addition to problems, the amount of powder paint drawn out from a pipe equipped with a suction device such as an injector for supplying powder paint to the paint gun also changes, which also causes the problem of poor coating.

  In view of this, the present invention provides a powder paint supply device having a fluid tank forced exhaust device in a paint tank, uniformizing the amount of powder paint taken out of the take-out device for sucking the flowing powder paint in the paint tank, The problem is to reduce the occurrence of defects.

  In order to solve the above-described problems, a powder coating material supply apparatus according to the present invention partitions a lower part of a paint tank that contains a powder coating material by a partition wall made of a porous material, and flows fluid air from below the partition wall. In the powder paint supply device provided with a take-out device for supplying the powder paint in the paint tank and flowing the powder paint in the paint tank and sucking the flowing powder paint in the paint tank, and having a forced exhaust device in the paint tank, A natural air circulation port for adjusting the internal pressure in the paint tank to an atmospheric pressure is installed in the upper part of the paint tank.

  The natural air circulation port can prevent intrusion of dust and the like from the natural air circulation port into the paint tank by directing the end on the air inflow side downward.

  A ball-type valve body that moves so as to close the natural air circulation port when the internal pressure in the paint tank rises above the atmospheric pressure may be provided in the natural air circulation port.

  Moreover, you may provide the filter which prevents intrusion of dust etc. in a natural air circulation port.

  As described above, the powder coating material supply apparatus of the present invention is provided with the natural air circulation port for adjusting the internal pressure to the atmospheric pressure in the paint tank even if the paint tank is provided with the forced exhaust device of the flowing air. The amount of powder paint taken out by the take-out device for sucking the flowing powder paint in the paint tank becomes uniform, and the occurrence of poor coating can be reduced.

1 is a schematic longitudinal sectional front view showing a first embodiment of the present invention. It is a schematic longitudinal front view which shows 2nd Embodiment of this invention. It is a schematic longitudinal front view which shows the 3rd Embodiment of this invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
The fluid type paint tank shown in FIG. 1 has a lower part of a tank body 1 containing a powder paint A, which is partitioned by a partition wall 2 made of a porous material such as a porous plate or cloth. Below, clean fluid air 3 dehumidified and deoiled from a compressor is supplied to remove lump and moisture of the powder coating material A stored in the tank body 1.

  On the upper surface of the tank main body 1, a suction device 5 such as an injector for pulling out the powder coating material A in the tank main body 1 and transporting it to the coating gun 4 is installed, and a pipe 6 attached to the suction device 5 is connected to the tank main body 1. The powder paint A is inserted into the flowing powder paint A, and the powder paint A is sucked from the pipe 6 and supplied to the coating gun 4.

  In the fluid paint tank, as described above, the fluid air 3 is supplied from below the partition wall 2, and the fluid air 3 eliminates the lump of the powder paint and removes the moisture of the powder paint. When fluid air is supplied into the tank, the internal pressure in the paint tank rises due to the supply of fluid air 3.

  For this reason, a suction device 7 such as an injector is installed on the upper portion of the tank body 1, and a drawing pipe 8 attached to the suction device 7 is inserted into a space above the flowing powder coating material A, and the tank body 1 is drawn from the drawing pipe 8. The supplied flowing air 3 is forcibly exhausted.

  In addition, a natural air circulation port 9 that communicates the inside of the tank body 1 and the outside of the tank body 1 is provided in the upper part of the tank body 1. When the internal pressure of the tank body 1 becomes a negative pressure by the natural air circulation port 9, external air flows into the tank body 1 from the natural air circulation port 9, and conversely, when the internal pressure of the tank body 1 becomes a positive pressure, The air in the tank body 1 flows out from the natural air circulation port 9, and the inside of the tank body 1 is always kept at atmospheric pressure.

  As a result, the amount of the powder paint A drawn out from the tank body 1 by the pipe 6 becomes uniform, and the discharge amount from the coating gun 4 becomes uniform, so that stable coating can be performed.

  Next, the embodiment shown in FIG. 2 is an example in which the end portion on the air inflow side of the natural air circulation port 9 is directed downward.

  By facing the end of the natural air circulation port 9 on the air inflow side downward, it is possible to prevent dust and the like from entering the tank body 1 from the natural air circulation port 9.

  In order to prevent intrusion of dust and the like from the natural air circulation port 9 into the tank body 1, a filter may be provided in the natural air circulation port 9.

  The embodiment shown in FIG. 3 is an example in which a ball-shaped valve body 10 such as a ping-pong ball is accommodated in a natural air circulation port 9 formed by a pipe. When the internal pressure in the tank body 1 rises above the atmospheric pressure, the valve body 10 moves toward the end portion of the natural air circulation port 9 formed with a small diameter, and the tip of the natural air circulation port 9 is moved to the valve body 10. When the internal pressure in the tank body 1 drops below the atmospheric pressure, the valve body 10 moves so as to open the tip of the natural air circulation port 9 and enters the tank body 1 from the tip of the natural air circulation port 9. Air flows in and the internal pressure in the tank body 1 returns to atmospheric pressure.

  By installing a pressure gauge (not shown) at the tip of the natural air circulation port 9 for detecting that the tip of the natural air circulation port 9 is blocked by the valve body 10, an increase in the internal pressure in the tank body 1 is detected. When the increase in the internal pressure in the tank body 1 is detected, the compressor that supplies the flowing air can be stopped to return the internal pressure in the tank body 1 to atmospheric pressure.

  A stopper 11 such as a wire mesh is provided in the natural air circulation port 9 so that the valve body 10 is not drawn into the tank body 1.

1: Tank body 2: Partition wall 3: Fluid air 4: Coating gun 5: Suction device 6: Pipe 7: Suction device 8: Extraction pipe 9: Natural air circulation port 10: Valve body 11: Stopper A: Powder coating

Claims (4)

  The lower part of the paint tank containing the powder paint is partitioned by a partition wall made of a porous material, and fluid air is supplied from the lower part of the partition wall into the paint tank to cause the powder paint in the paint tank to flow. In a powder coating material supply device provided with a take-out device for sucking the flowing powder coating material in and having a forced exhaust device in the coating material tank, natural air for adjusting the internal pressure in the coating material tank to the atmospheric pressure above the coating material tank A powder coating material supply device characterized in that a distribution port is provided.   2. The powder coating material supply apparatus according to claim 1, wherein an end of the natural air circulation port on the air inflow side faces downward.   The powder coating material according to claim 1 or 2, wherein the natural air circulation port has a ball-type valve body that moves so as to close the natural air circulation port when the internal pressure in the coating material tank rises above the atmospheric pressure. Feeding device.   The powder coating material supply apparatus according to any one of claims 1 to 3, wherein a filter that prevents intrusion of dust or the like is provided at a natural air circulation port.

Images