JPH10216569A - Coating material spray head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for improving the uniformity of a powdery coating material. SOLUTION: A coating material spray head 38 is provided with a rotating spray instrument 60 and a rotator 42 for rotating the rotating spray instrument. A first connecting section for feeding a coating material into the spray instrument 60 and a second connecting section for supplying power to a rotator are included in the head 38. The coating material is a powdery material accompanying in the flow of fluidized gas, and the rotator 42 is a turbine rotator driven by compressed gas, and an output shaft 52 is extended from the first side section of the turbine rotator. The spray instrument 60 is mounted on the output shaft 52. The turbine rotator is provided with a second side section facing as a whole in the direction opposite to the first side section. The turbine rotator is provided at least with one air exhaust passage having an exhaust port, and air is exhausted out of the exhaust port on the side of two side sections of the turbine rotator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in the uniformity of a powder coating on an object coated with the powder coating.

[0002]

BACKGROUND OF THE INVENTION Many rotary paint sprayers are known. For example, US Pat. Nos. 3,536,514, 4,
No. 037,561, No. 4,114,564, No. 4,3
No. 81,079, No. 4,447,008, No. 5,35
Systems described in US Pat. Nos. 3,995 and 5,433,387, as well as Aerobell® powder coaters (from the automotive division of ITW), Aerobell® and Aerobell Plus® ) Rotary atomizer or atomizer (DeVilbiss Ransburg Industrial Liquid Sys)
tems). Some of these rotary paint spray systems are designed to spray powder paint. For example, see US Pat. No. 3,536,5.
No. 14, No. 4,037,561, No. 4,114,56
See No. 4, No. 5,353,995 and Aerobell powder coaters.

[0003] Many other paint spraying devices are known. For example, U.S. Pat. Nos. 3,263,127, 3,
870,232, 4,024,815, 4-1
No. 16,384, No. 4,232,832, No. 4,23
No. 5,381, No. 4,788,933, No. 4,99
No. 3,645, No. 5,022,590, No. 5,24
Nos. 0,185, 5,323,547 and 5,33
5,828, DE-A 28 37 428
And the systems described in French Patent Application No. 2,605,533, and also Aerobell® and Aerobell Plus® rotary atomizers (DeVilbiss Ransburg Industrial Li
quid Systems). Although it is not to say that the investigation of the prior art is perfect, no more suitable prior art documents have been obtained in connection with the present invention.

[0004] Of the above prior art documents, US Pat.
No. 353,995 teaches a method of discharging the exhaust of a turbine rotator of a rotary atomizer toward a powder cloud formed in front of the turbine rotator, ie, around the rotary atomizer. Seems to be. US Patent No. 4,44
No. 7,008 includes such teaching in connection with a rotary liquid atomizer. Certainly, for example, US Pat.
No. 7,008 teaches that venting the exhaust of the turbine forward to the center of the atomized liquid paint allows for better control of the pattern of the liquid paint.

[0005]

SUMMARY OF THE INVENTION In accordance with the present invention, a paint spray head includes a rotary sprayer and a rotator for rotating the sprayer. The head includes a first connection for supplying paint to the sprayer and a second connection for supplying power to the rotator. The paint is a powder material entrained in the flow of the fluidizing gas, the rotator is a turbine rotator driven by compressed gas,
An output shaft extends from the first side. The spray device is attached to an output shaft. The turbine rotator has a second side generally facing away from the first side. The turbine rotator has at least one exhaust passage with an exhaust port that exhausts on a second side of the turbine rotator.

[0006] Illustratively, the paint spray head further includes a housing with first and second housing portions. The first housing portion includes a first housing rotator.
And a second housing portion generally surrounds a second side of the turbine rotator. The exhaust port is in communication with the interior of the second housing portion. As another example, the exhaust port is provided on a second side of the turbine rotator.
As yet another example, a muffler is provided to receive turbine exhaust from an exhaust port. The content of the present invention may best be understood with reference to the following detailed description and accompanying drawings that illustrate the invention.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The rotary powder coater or powder spray head 38 of the present invention has a manifold 40. Manifold 40
As an example, for example, Reading, Pennsylvania
(Reading) "Acetron (Acetro) available from DSM Engineering Plastic Products, Inc.
n: registered trademark) GP "is made from a general-purpose acetal resin.
An air turbine motor assembly (hereinafter, sometimes simply referred to as “turbine”) 42 is attached so as to extend forward from a front portion 44 of the manifold 40. The motor assembly 42 is, for example, 150SA or 550SA Delrin (De
lrin: turbine motor housing 4 made of material
6 and a high voltage contact plate 48, for example made of aluminum.
A turbine air nozzle plate 50 made of, for example, aluminum, an air turbine shaft 52 having a central passage 54 penetrating in the axial direction, and a thrust bearing spacer 56.
And a turbine rotor 58. The air turbine motor assembly 42 is, for example, Pho, Ann Arbor, Michigan.
It may be the product D1245-07 available from WestwindAir Bearings at enix Drive. A supply pipe 59 made of, for example, glass fiber reinforced Delrin extends to the downstream side of the center of the passage 54.

A powder bell cup assembly 60 is screwed to the front end 62 of the shaft 52. The powder bell cup assembly 60 includes, for example, a bell cup 64 made of filled or unfilled polyetheretherketone (PEEK) and a bell cup made of, for example, Teflon® or Delrin material. It has an insert or liner 66 and a diffuser 68 made of, for example, Teflon or Delrin material, all joined together by three circumferentially equally spaced slotted flat screws 70. Diffuser 68 is disclosed, for example, in U.S. patent application Ser.
It is configured as described in 377,816.
The outer surface 74 'of the bell cup 64 is disclosed in U.S. Patent Application Serial No. 08 / 451,570, filed May 26, 1995,199.
U.S. patent application Ser. No. 08 / 437,21, filed May 8, 2005
No. 8 and U.S. Patent Application No. 0 filed May 26, 1995
Processing as described in No. 8 / 451,541 is performed. The disclosures of these four U.S. patent applications are incorporated herein by reference. The constituent material of the bell cup 64 is sufficiently tolerant to the above processing of its outer surface 74 '. The composition of the liner 66 is somewhat less sensitive to the impact melting of many powder coatings of the type sprayed by the coater 38.

A somewhat bullet-shaped front shroud 74 with a shaping air ring cap 76 includes a front portion of the manifold 40, a turbine motor assembly 42, and a majority of the powder bell cup assembly 60 ( However, liner 6
6 (except for the foremost portion thereof including a powder discharge slot 78 formed between the diffuser 68 and the diffuser 68). Radially outwardly and axially extending ribs 80 on shroud 74 help to form an annular shaping air slot between shroud 74 and shaping air ring cap 76, which air slot includes:
It is provided in the shaping air passages 81, 82, 84 provided in the manifold 40, the turbine housing 46, and the front shroud 74, respectively. Complementary mating surfaces 86, 8 of shroud 74 and manifold 40
8 has a maze-like shape with a complicated shape so that the path crossing the surface of these two components is long. This reduces the risk of tracking occurring, for example, returning high levels of voltage applied to the high voltage contact plate 48 during operation of the coater 38 to, for example, the grounded coater 38 support.

The rear manifold plate assembly 90 includes three
The book has a rear manifold mounting flange 92 that is mounted to a rear manifold mounting plate 96 by screws 94 that are circumferentially equally spaced. The rear face 98 of the plate 96 is flat and smooth. Rear shroud 10 having a right circular column shape as a whole
0 is fitted in an annular groove 102 formed by the adjacent surfaces of the plate 96 and the flange 92, and its front part is fitted in an annular groove 104 provided on the rearward facing surface of the manifold 40. . Suitable fittings and lines are provided by fluidized powder ports (PDR) (fitting 96-) provided on plate 96 and manifold 40.
1, 40-1 and line 91), powder cloud shaping air port (SHP) (fittings 96-3, 40-3 and line 95), turbine drive air port (DRV)
(Fittings 96-2, 40-2 and line 93), turbine bearing air ports (1BRG and 2BRG) (Fittings 96-4-1, 96-4-2, 40-4-1, 40-4)
-2 and lines 97, 103) and a turbine braking air port (BRK) (fittings 96-5, 40-5 and line 101). Turbine air exhaust ports (1EXH and 2EXH) (port 96-6) provided in plate 96 exhaust turbine exhaust air from rear shroud 100. This air is exhausted from the turbine through a muffler 106 attached to two exhaust ports (40-6) provided in the manifold 40.

An optical fiber speed control fixture (FO) (4)
0-7 and 96-7) correspond to the manifold 40 and the plate 96.
Are provided in both. The fiber optic speed control fixture 96-7 of the plate 96 includes an edge 110 of the plate 96.
A threaded hole 108 is provided in the lateral direction, extending into the hole. Connect the fiber optic terminals to the flat surface 9 of the plate 96.
A presser screw is screwed into the screw hole 108 for accurate positioning at 8. This facilitates alignment of the fiber optic terminal 114 with a lens in which the plate 96 is quickly and easily mounted in a flat surface mounted by bolts 116. This arrangement eliminates the need to spend too much time aligning the terminal 114 and the lens if the painter 38 must be removed for any reason, including replacement with a painter of a similar design. Fluidized powder port (96-1) on surface 98, powder cloud shaping air port (96-3), turbine drive air port (96-2), turbine bearing air port (96-4-1, 96-4-2) and the turbine braking air port (96-5) are provided with an O-ring seal 99 surrounding them.

A substantially rectangular cylindrical boss 120 is provided on the front or inner surface 122 of the plate 96.
A substantially cylindrical relief 124 is provided on the rear surface of the manifold 40 directly opposite the boss 120. ITW R
An ansburg MICRO-PAK® high voltage transformer and cascaded voltage multiplier 126 are provided in tight connection between the boss 120 and the relief 122. The floor 128 of the relief 124 is maze-shaped to complement the configuration of the high voltage output 130 of the high voltage multiplier 126. Also, by this form,
The path from the high-level voltage output terminal 131 of the multiplier 126 to the ground section across the surface of the multiplier 126 and the manifold 40 can be lengthened. Manifold 40, turbine motor assembly 42 and front shroud 74 are supported from rear manifold plate 96 by four circumferentially equally spaced support rods 132,
The support rod 132 has a threaded end that can be screwed into a complementary screw hole 133 provided in the manifold 40. The support rod 132 has a holding screw 135
To the plate 96.

The bearing air is supplied to the air bearing of the turbine 42 through a 1RG port. The 2BRG port couples the air bearing to a pressure sensitive switch (not shown). When the switch detects a decrease in pressure in the air bearing,
The flow of the fluidized powder paint and the flow of the driving air are stopped, and the turbine 42 is stopped for its protection. A low alternating voltage, e.g., 12 VAC to 30 VAC, is applied to the low voltage terminal of the multiplier 126 via a low voltage connector (LV) 96-8 on the plate 96. The low-voltage connector 96-8 is held at a predetermined position by a set screw (not shown) screwed into a bore 137 provided on the edge 110 of the plate 96. Bore 137 is connector 96
Intersects the -8 fitted bore. For example, a wire 136 made of phosphor bronze has several turns of a compression spring 138 formed at one end thereof. The end 140 of the wire 136 opposite to the spring 138 fits into the cavity of the multiplier 126 in which the terminal 131 is stored. Spring 138
Are compressed in contact with the high voltage contact plate 48 during assembly of the turbine 42 into the manifold 40.

[0014] The bearing air of the turbi 42 is supplied to the fixture 40-
4-1 is supplied to an air bearing 145 of the turbine 42 through a passage 144. This bearing air is supplied to the mounting fixture 40-
It is detected through the passage 146 by the above-described air bearing pressure detection switch connected to 4-2. If bearing air pressure is present at the fixture 40-4-2, drive air for the turbine 42 is applied to the fixture 40-2 and passage 1
The powder bell cup assembly flows forward through the passage 50 and from this passage through the nozzle 152 of the turbine 42 and strikes the blades of the turbine rotor 58, thereby being attached to the rotor 58 and the end 62 of the shaft 52. Rotate 60.

The rotation speed signal of the turbine 42 is, for example, De.
Vilbiss Ransburg Model LSMC5003 Induction-
Optical fiber signal transmitter (inductive-to-fiber opticsi
back to the gnaltramsmitter 156, and coupled to each other, the transmitter transmits light each time it detects passage of a small magnetic disk (not shown) provided in the rearwardly facing surface of the rotor 58 facing it. Generate a pulse. This signal is transmitted to the surface 98 of the plate 96 through a fiber optic coupler 114 and further to a speed control device (not shown) of the turbine 42, for example, through another similar fiber optic coupler (not shown). The speed control device controls the supply of driving air to the fixture 96-2, thereby controlling the rotation speed of the turbine 42.

The braking air for reducing the rotation speed of the turbine 42 is supplied from the fitting 40-5 to the braking air nozzle 162 through the passage 160, and this nozzle supplies the supplied braking air to the rear of the rotor 58. To the mounting bracket 40-5 of the braking air bucket formed on the surface facing.
The exhaust air from the low pressure side 164 of the turbine 42
0-6 and rear shroud 10 through muffler 106
It is exhausted into 0. The exhaust air is extracted from the shroud 10 through the 1EXH and 2EXH ports of the plate 96. Thus, the exhaust of the turbine 42 is directed radially and away from the region located directly outwardly from the slot 78 where the atomized powder cloud is formed and maintained, in a direction toward the powder cloud. Is not exhausted.

As best seen by comparing FIGS. 25 and 26, the turbine 4 is not a forward exhaust system as taught, for example, in US Pat. No. 4,447,008.
By performing the exhaust in the second step, the uniformity of the thickness of the powder coating material to be coated can be considerably improved. It should be noted that the paint release rate of the conventional powder paint coater, whose operation resulted in FIG. 25, and the paint release of the powder paint coater of the present invention, which resulted in FIG. The speeds were different from each other. In consideration of this, the scales of the horizontal axes in FIGS. 25 and 26 are different from each other. More specifically, a conventional powder coating machine was used to supply 300 g of powder per minute, and the curve of FIG. 25 was obtained. 200g per minute using powder paint coater 38
Was supplied, and the curve of FIG. 26 was obtained. If the same release rate is used for both the conventional coater and the inventive coater 38, it is unlikely that the results shown by comparison of the overall profiles of FIGS. 25 and 26 will be invalid.

The powder cloud is shaped by the shaping air supplied through fixture 96-3, line 95, fixture 40-3 and passageways 81,82,84.

Referring now to FIGS. 23 and 24, the mating plate 200 has a flat front surface 202 facing the rear surface 98 of the plate 96. Screw holes 204 for receiving cap screws 206 in the flange 92 are provided at equal circumferential intervals around the front surface 202. By tightening the holding screw 206 into the screw hole 204, the O-ring 99
0 of both matched fluidized powder ports (PD
R), drive air port (SHP), sheping air port (BRG), bearing air port (1BRG, 2BR)
G), compressed between the surfaces 98, 202 around the braking air port (BRK), the fiber optic port (FO) and the exhaust port (1EXH and 2EXH). With this arrangement, when the two plates 96, 200 are secured to each other as described above, each of these passages is effectively sealed at any time, yet the dispenser is disassembled, reconnected, and as needed or desired. Then, it can be quickly and easily exchanged for another coater of the same or similar form.

Since the fluidized powder supplied to the fixture 96-1 is somewhat penetrable, the quick detachable plate 9
The configuration of the 6,200 PDR fittings 96-1 is somewhat different. Specifically, the fixture 96-1 includes an additional O
It has a nipple 210 provided with a sealing seal 99.
The nipple 210 of the fitting 96-1 slides into a relief 212 provided on the surface 202 of the plate 200 for this purpose and is enclosed in the relief by this additional O-ring 99. The plate 200 is mounted on any desired type of mounting means, such as a stand, reciprocator, etc., so that the powder bell cup assembly 60 is in a suitable position adjacent to the substrate from which the powder coating is to be sprayed. Be placed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a powder coating machine embodying the present invention.

2 is another longitudinal sectional view of details of the powder coating machine shown in FIG. 1;

FIG. 3 is an exploded vertical sectional view of details of the powder coating machine shown in FIG. 1;

FIG. 4 is an exploded vertical sectional view of details of the powder coating machine shown in FIG. 1;

FIG. 4A is a detailed enlarged partial view of FIG. 4;

FIG. 5 is a sectional view of the powder coating machine shown in FIG.

FIG. 6 is a sectional view of the powder coating machine shown in FIG.

FIG. 7 is a cross-sectional view of a detail of the powder coating machine shown in FIG. 1 taken along the line 7-7 in FIGS. 5 and 6;

FIG. 8 is a sectional view of the powder coating machine shown in FIG.

FIG. 9 is a side view of certain details of the powder coating machine shown in FIG.

10 is a sectional view taken along line 9-9 of the details of the powder coating machine shown in FIG. 9;

11 is a partial cross-sectional view of details of the powder coating machine shown in FIG. 1 taken along line 11 and the axis of FIG. 8;

FIG. 12 is a partial cross-sectional view of the details of the powder coating machine shown in FIG. 1 taken along line 12 and the axis of FIG. 8;

13 is a partial cross-sectional view of a detail of the powder coating machine shown in FIG. 1 taken along line 13 and the axis of FIG. 8;

FIG. 14 is a cross-sectional view of a detail of the powder coating machine shown in FIG. 1 taken along line 14-14.

FIG. 15 is a partially exploded partial longitudinal sectional view of details of the powder coating machine shown in FIG. 1;

16 is a partial cross-sectional view of details of the powder coating machine shown in FIG. 1 taken along line 16 and the axis of FIG. 8;

17 is a partial cross-sectional view of details of the powder coating machine shown in FIG. 1 taken along line 17 and the axis of FIG. 8;

FIG. 18 is a partial cross-sectional view of a detail of the powder coating machine shown in FIG. 1 taken along line 18 and the axis of FIG.

FIG. 19 is a partial cross-sectional view of a detail of the powder coating machine shown in FIG. 1 taken along line 19 and the axis of FIG. 8;

FIG. 20 is a partial cross-sectional view of details of the powder coating machine shown in FIG. 1 taken along line 20 and the axis of FIG. 8;

FIG. 21 is a partial cross-sectional view of the details of the powder coating machine shown in FIG. 1 taken along line 21 and the axis of FIG. 8;

FIG. 22 is a partial cross-sectional view of details of the powder coating machine shown in FIG. 1 taken along line 22 and the axis of FIG. 8;

FIG. 23 is a side view of a mounting plate for mounting the powder coating machine shown in FIG. 1;

FIG. 24 shows details 24-24 of the powder coating machine shown in FIG.
Sectional view

FIG. 25 is a graph showing the thickness profile of a powder coating obtained using a forward exhaust spray head.

FIG. 26 is a graph showing the thickness profile of a powder paint obtained by using the rear exhaust type spray head of the present invention.

[Explanation of symbols]

 Reference Signs List 38 rotary powder coating machine 40 manifold 42 air turbine motor assembly 60 powder bell cup assembly 68 diffuser 74 front shroud 76 shaping air ring cap 90 rear manifold plate assembly 96 manifold mounting plate 100 rear shroud 106 muffler 156 Transmitter

Claims (7)

[Claims] 1. A paint spraying head having a rotary sprayer and a rotator for rotating the same, the head having a first connection for supplying paint to the sprayer and a second connection for supplying power to the rotator. Wherein the paint is a powdered material entrained in the flow of the fluidizing gas, and the rotator is a turbine rotator driven by a compressed gas, the output shaft extending from a first side thereof; The sprayer is attached to the output shaft, the turbine rotator has a second side generally facing in a direction opposite to the first side, and the turbine rotator includes an exhaust port. A paint spray head having at least one exhaust passage with a vent port exhausting on a second side of the turbine rotator. 2. The system further comprises a housing having first and second housing portions, the first housing portion generally surrounding a first side of the turbine rotator and an output shaft, and a second housing portion. 2. The paint spray head of claim 1, wherein the housing portion of the second housing portion entirely surrounds a second side of the turbine rotator, and the exhaust port communicates with the interior of the second housing portion. . 3. The exhaust port according to claim 2, wherein the exhaust port is a second port of the turbine rotator.
The paint spray head according to claim 2, wherein the paint spray head is provided on a side portion of the paint sprayer. 4. The paint spray head according to claim 3, further comprising a muffler provided to receive turbine exhaust from an exhaust port. 5. The paint spray head according to claim 2, further comprising a muffler provided to receive turbine exhaust from an exhaust port. 6. An exhaust port according to claim 2, wherein said exhaust port is a second port of said turbine rotator.
The paint spray head according to claim 1, wherein the paint spray head is provided on a side portion of the paint spray head. 7. The paint spray head according to claim 6, further comprising a muffler provided to receive turbine exhaust from an exhaust port.