JP2000271513A - Apparatus for taking out powder coating from fluidized powder coating tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a powder coating in a fluidized state from being abnormally delivered through an opening between a conveying screw and a guide pipe to thereby stabilize the delivery of the coating by inclining the rotation shaft of the conveying screw upwardly in the conveying direction of the screw. SOLUTION: A guide pipe 4 is inserted diagonally into a fluidized powder coating tank 1 through the side thereof, and the rotation shaft 5a of a conveying screw 5 is inclined upwardly in the conveying direction of the screw 5. The powder coating flowing into the guide pipe 4 from a take-in port 13 is conveyed toward the discharge port 12 of the guide pipe 4 by a conveying blade 5b attached to the rotation shaft 5a, thus being caused to fall down into a discharge pipe 9, and is sucked by an injector 10 to be conveyed to a coating gun. Thus, air contained in the coating is efficiently caused to escape along the upper inner surface of the guide pipe 4, suppressing the flow of the powder coating. Therefore, the coating is prevented from being abnormally delivered through an opening between the conveying screw 5 and the guide pipe 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drawer for quantitatively extracting powder paint from a fluid powder paint tank containing powder paint in a flowing state by flowing air.

[0002]

2. Description of the Related Art In an electrostatic powder coating equipment, a fluid type powder coating tank containing a powder coating in a flowing state by flowing air to loosen or dehumidify the powder coating supplied to a coating gun. Is often used.

Conventionally, as a drawing device for quantitatively drawing powder paint from such a fluid type powder paint tank and supplying the powder paint to a suction port of an injector which conveys the powder paint to a coating gun, a rotary shaft is used. Consisting of a transport screw having transport blades around it and a guide pipe surrounding the transport screw, a guide pipe on the loading side of the transport screw is provided with an inlet for drawing powder paint, and a guide on the transport side of the transport screw. Some pipes have an outlet for powder paint.

[0004] In the drawer device, the guide tube is connected to the flow-type powder coating tank such that the inlet of the guide tube is located inside the flow-type powder coating tank. Installed in a state inserted from the side, or provided with a dropout for powder paint at the bottom of the flowable powder paint tank, and connected this dropout to the inlet of the guide pipe by a connecting pipe However, in any case, conventionally, the conveying screw in the guide tube is installed such that the rotation axis of the conveying screw is horizontal.

[0005]

In recent years, in powder coating, there has been an increasing demand for uniformity and thinning of the coating film. For this reason, the powder coating also has an average particle size of 30 to 4 particles.
15 μm smaller than the previous one such as 0 μm
There is a tendency to use fine powder coatings of up to 25 μm.

When the powder paint of such fine particles is drawn out of the fluid powder paint tank by using the above-mentioned conventional drawer comprising a conveying screw and a guide tube, the powder paint is placed in the fluid powder paint tank. In this case, even if the transport screw is stopped, the powder paint may flow out through the gap between the transport screw and the guide tube, causing an error in the amount of powder paint to be drawn out. As a result, there has been a problem that stable powder coating cannot be discharged.

In view of the above, according to the present invention, when the conveying screw is stopped, or when the conveying screw is rotated to draw out the powder coating, the powder coating in a flowing state causes a gap between the conveying screw and the guide tube to be formed. It is an object of the present invention to stably discharge the powder coating without abnormal discharge of the powder coating.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a transport screw having a transport blade around a rotary shaft, and a guide tube surrounding the transport screw. An inlet for drawing powder paint in a fluid type powder paint tank containing powder paint in a flow state by air is provided, and a discharge pipe for powder paint is provided in the guide pipe on the discharge side of the transport screw. In the powder paint drawing device in the fluid type powder paint tank, the rotation axis of the transport screw is inclined upward in the transport direction of the transport screw.

As described above, the rotation axis of the transport screw is
When the powder paint is inclined upward in the conveying direction of the conveying screw, the powder paint is conveyed in an inclined state upward, so that the air contained in the powder paint in the flowing state during the conveyance,
As it approaches the outlet of the guide tube, it effectively escapes along the upper surface inside the guide tube as shown in FIG.
Since the flow of the powder paint near the discharge port of the guide tube is suppressed, when the transfer screw is stopped or when the powder screw is pulled out by rotating the transfer screw, the gap between the transfer screw and the guide tube is reduced. Abnormal discharge of the powder paint through the gap can be prevented.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

In the embodiment shown in FIG. 1, the guide pipe 4 is inserted obliquely from the side of the tank 1 of the fluid type powder coating tank, and the rotating shaft 5a of the conveying screw 5 is moved in the conveying direction of the conveying screw 5. It is designed to incline upward.

In the fluid type powder coating tank, a bottom surface of the tank 1 is partitioned by a porous plate 2, a flowing air is supplied to the lower surface side of the porous plate 2, and the flowing air passing through the porous plate 2 is supplied to the tank 1 by a flowing air. It has a structure that allows the powder paint inside to flow.

On the side surface of the tank 1, a powder paint outlet 3 is provided, and a powder paint extracting device is detachably installed in the outlet 3.

The drawing device comprises a conveying screw 5 having a conveying blade 5b around a rotary shaft 5a, and a guide tube 4 surrounding the conveying screw 5. The transport blades 5b are provided at a constant pitch in the axial direction of the rotating shaft 5a, but may be provided at a pitch that becomes narrower continuously or stepwise from the loading side to the loading side.

A connection ring 6 that is inclined with respect to the side surface of the tank 1 is fixed to an outer peripheral edge of the outlet 3 of the tank 1, and a connection cylinder 7 is fitted into the connection ring 6 so as to be freely inserted and removed. . A seal ring 8 is fitted on the outer surface of the connection cylinder 7.

A discharge tube 9 is formed integrally with an end of the connection tube 7. At a lower end of the discharge tube 9, a connecting portion 11 connected to a suction port of the injector 10 is formed.

A discharge port 12 is provided at one end of the guide tube 4, and the discharge port 12 is inserted into the connection tube 7 so that the discharge port 12 is positioned within the discharge tube 9. The guide tube 4
It is fixed to the connection tube 7 and can be freely inserted into and removed from the connection ring 6 together with the connection tube 7.

The other end of the guide tube 4 is connected to the tank 1
A draw-in pipe 4 which is inserted into the tank 1 and located in the tank 1 is provided with an inlet 13 for powder paint in the tank 1.

The inlet 13 of the guide tube 4 may be formed on either the peripheral surface or the end surface of the guide tube 4.

In the embodiment shown in FIG.
3 is formed on the upper surface side of the inner surface of the guide tube 4. As described above, when the inlet 13 is formed on the upper surface side of the peripheral surface of the guide tube 4, the powder paint easily flows into the guide tube 4, and the flowing air hardly enters the guide tube 4 from below. It is easy to keep the powder paint flowing into the guide tube 4 stationary. For this reason, the air contained between the powder coatings in the guide tube 4 easily escapes.

In the embodiment shown in FIG.
3 is formed on the end cap 14 on the end face of the guide tube 4. Since the end cap 14 is fitted to the end of the guide tube 4 so as to rotatably support the end of the rotary shaft 5 of the transport screw installed in the guide tube 4, the inlet 13 rotates. A plurality of shafts 4 are formed around the support portion. A guide portion 15 that opens to the side surface is formed integrally with the end surface of the end cap 14.

In the embodiment shown in FIG. 4, similarly to the embodiment shown in FIG. 3, an inlet 13 is formed in an end cap 14 on the end face of the guide tube 4, and in this embodiment, The guide part 15 is formed so as to open to the upper surface side. When the guide portion 15 is formed so as to open to the upper surface side as described above, the powder paint is settled in the guide portion 15, so that the air contained between the powder paints easily escapes.

Next, the guide tube 4 is inserted into the guide tube 4.
A transport screw 5 that transports the powder paint drawn into the inside toward the outlet 12 is provided.

Both ends of the rotating shaft 5 a of the transport screw 5 are rotatably supported by the end cap 14 of the guide tube 4 and the discharge tube 9. The end of the rotating shaft 5 a of the conveying screw 5 on the side of the discharge cylinder 9 penetrates through the discharge cylinder 9 and is connected to a motor 16.

The motor 16 is provided on the outer surface of the discharge cylinder 9.
It is detachably attached by bolts 17. The drive shaft 18 of the motor 16 and the rotating shaft 5 a of the transport screw 5 are detachably connected via a coupling 19.

A bearing cylinder 20 of the rotary shaft 5a is fitted in a through hole of the discharge cylinder 9 through which the rotary shaft 5a of the transport screw 5 penetrates. Bearing cylinder 2 through which the above-mentioned rotary shaft 5a is inserted
The shaft hole 0 has a small diameter on the outer surface side of the discharge cylinder 9 and a large diameter on the inner surface side of the discharge cylinder 9, and the end of the rotary shaft 5 a is inserted through the small diameter portion without any gap. A predetermined space 21 is formed between the outer peripheral surface and the outer peripheral surface. Air is blown into the space 21 from an air supply pipe 23 via an air introduction hole 22 formed in the discharge cylinder 9 and the bearing cylinder 20. Further, the transfer blade 5b is connected to the discharge port 1 of the guide tube 4.
The slide cylinder 24 is not formed on a portion protruding from the outer cylinder 2, and is slidably covered on the outer surface of the rotary shaft 5 a crossing the discharge cylinder 9 with a predetermined gap between the slide cylinder 24 and the outer surface of the rotary shaft 5 a. ing. A rectifying plate 25 that closes the outlet 12 of the guide tube 4 is provided at an end of the slide tube 24 on the guide tube 4 side.
Has been fixed. The current plate 25 is urged in a direction to close the discharge port 12 of the guide tube 4 by a spring 26 housed in a gap formed between the slide cylinder 24 and the rotating shaft 5a. On the other hand, the end of the slide cylinder 24 on the bearing cylinder 20 side is a space 21 formed between the large diameter portion of the bearing cylinder 20 and the outer peripheral surface of the rotating shaft 5a.
When the rotating shaft 5a is driven and the powder coating material is transferred to the discharge port 12 side and a pressing force is applied to the rectifying plate 25, the spring 26 is contracted and the sliding cylinder 24 is An end is accommodated in the space 21, and a space between the current plate 25 and the discharge port 12 is opened. Further, air is blown into the space 21 from an air supply pipe 23, and the air blown into the space 21 passes through a gap between the slide cylinder 24 and the rotary shaft 5a, and flows into the guide pipe. The powder paint flowing out from the outlet 12 into the discharge tube 9 is dispersed by the outflowing air.

The lower end of the discharge cylinder 9 is connected to the injector 1
0 is connected to the suction port. Inlet 13 for guide tube 4
The powder paint flowing into the guide tube 4 from the discharge pipe 1 of the guide tube 4 is rotated by the rotating shaft 5a while the flowing air is being removed.
The liquid is transferred toward the discharge pipe 2, falls from the discharge port 12 into the discharge cylinder 9, is sucked by the suction port of the injector 10, and is conveyed to the coating gun by the conveying air of the injector 10.

Next, in order to effectively extract the flowing air between the powder coatings in the guide tube 4, the following means can be taken.

First, in the embodiment shown in FIG. 5, a mesh 27 having a mesh size through which the powder coating material passes is stretched in the inlet 13 of the guide tube 4, and a vibrator 28 is attached to the mesh 27. In this case, when the powder coating material passes through the net 27, the vibration of the vibrator 28 effectively removes the flowing air between the powder coating materials.

In the embodiment shown in FIG. 6, an air vent window 29 made of a porous material is provided in a part of the guide tube 4, and a suction device 30 is connected to the air vent window 29. Thereby, the flowing air contained in the powder coating material passing through the guide tube 4 is forcibly extracted from the air vent window.

Next, the embodiments shown in FIGS. 2 to 6 are examples in which the drawer is installed obliquely on the side surface of the tank 1. However, the embodiment shown in FIG. The device is provided at right angles to the side surface of the tank 1 and the tank 1 itself is inclined so that the rotation shaft 5a of the transport screw 5 of the drawer device is inclined upward in the transport direction of the transport screw 5. I have.

In the embodiment shown in FIGS. 8 and 9, a drop 31 for powder paint is provided on the bottom of the tank 1 and the drop 3
FIG. 8 shows an embodiment in which the drawer device is installed obliquely with respect to the falling port 31 in FIG.
Installed the drawer at right angles to the drop port 31,
The embodiment in which the tank 1 itself is inclined is shown.

In each of the above examples, the inclination angle of the rotating shaft 5a of the conveying screw 5 is preferably 5 to 30 degrees. FIG.
Using the apparatus of the embodiment, the inclination angle of the rotation shaft 5a of the transport screw 5 is set to 0 degrees, 5 degrees, 10 degrees,
Table 1 shows the results of an experiment in which five types of two resin-based powder coatings were pulled out from the tank 1 at 20 degrees and 30 degrees. As a result of this experiment, when the angle of the rotation axis 5a of the transport screw 5 is 0 degree, the powder fluidized from the gap between the transport blade 5b of the transport screw 5 and the guide tube 4 even when the transport screw 5 is stopped. The paint leaked out and a stable powder paint could not be obtained.
It was confirmed that as the angle was increased to 0, 20, and 30 degrees, the quantitativeness of the amount of the powder paint to be drawn out improved.

In this experiment, the pressure of the fluidizing air in the tank 1 was kept constant at 2.0 kg / cm. However, depending on the coating material, by lowering this pressure, the angle of the rotating shaft 5a of the transport screw 5 could be reduced. It is possible to improve the accuracy of the withdrawal amount even if is reduced.

[0035]

[Table 1]

[0036]

As described above, according to the drawing device of the present invention, the powder paint can be quantitatively pulled out from the fluid type powder paint tank, so that the powder from the coating gun for electrostatic powder coating can be obtained. The discharge amount of the body paint can be made uniform.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a first embodiment of the present invention.

FIG. 2 is an enlarged view of FIG. 1;

FIG. 3 is a partial cross-sectional view showing a second embodiment of the present invention.

FIG. 4 is a partial sectional view showing a third embodiment of the present invention.

FIG. 5 is a partial cross-sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a partial cross-sectional view showing a fifth embodiment of the present invention.

FIG. 7 is an overall sectional view showing a sixth embodiment of the present invention.

FIG. 8 is an overall sectional view showing a seventh embodiment of the present invention.

FIG. 9 is an overall sectional view showing an eighth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tank 2 Porous plate 3 Draw-out port 4 Guide pipe 5 Conveyor screw 5a Rotating shaft 5b Conveyor blade 6 Connection ring 7 Connection cylinder 8 Seal ring 9 Discharge cylinder 10 Injector 11 Connection part 12 Discharge port 13 Intake port 14 End cap 15 Guide part Reference Signs List 16 motor 17 bolt 18 drive shaft 19 coupling 20 bearing cylinder 21 space 22 air introduction hole 23 air supply pipe 24 slide cylinder 25 rectifying plate 26 spring 27 mesh body 28 vibrator 29 air vent window 30 suction device 31 drop port 32 connection pipe

Claims (5)

[Claims] The present invention comprises a transport screw having transport blades around a rotary shaft, and a guide tube surrounding the transport screw. In the fluid type powder coating tank in which a powder coating in the fluid type powder coating tank containing therein is provided, and the guide pipe on the discharge side of the conveying screw is provided with an outlet for the powder coating. A powder paint withdrawal device for a fluid type powder paint tank, wherein the rotation axis of the transport screw is inclined upward in the transport direction of the transport screw. 2. The fluidized powder paint tank according to claim 1, wherein said guide pipe is inserted into a side surface of said fluidized powder paint tank such that an inlet of said guide pipe is located inside said fluidized powder paint tank. Powder paint drawer in a dry powder paint tank. 3. A powder paint dropping port is provided at a lower portion of the fluid type powder paint tank, and the dropping port is connected to an inlet of the guide pipe by a connecting pipe. Powder paint drawer in a fluid type powder paint tank. 4. The powder paint drawing device for a fluid type powder paint tank according to claim 1, wherein the inclination angle of the rotation axis of the transport screw is 5 to 30 degrees. 5. The flowable powder according to claim 1, wherein a pitch of the transport blades of the transport screw is reduced continuously or stepwise from a loading side to a loading side. Powder paint drawer in paint tank.