JPH0141496Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is a type of paint sprayer in which the atomized charged paint particles are directed toward the object to be coated along the lines of electric force by rotating the rotary atomizer head at high speed and are applied to the object to be coated. This invention relates to an electrostatic spray device.

Conventionally, this type of electrostatic spraying device supports a rotating shaft via a bearing such as a ball bearing or a roller bearing, an air-driven turbine is attached to one end of the rotating shaft, and a rotating atomizer is attached to the other end. The rotary atomizing head is attached, and the rotary atomizing head is rotated at high speed by the turbine while applying a high voltage to atomize the paint supplied to the rotary atomizing head. To atomize the paint, the rotating atomizer head is rotated at high speed, and the paint supplied to the liquid contact surface is made to flow down to the discharge edge as a thin film-like liquid stream by centrifugal force. A paint liquid system (cusp) is discharged from the discharge edge, and the liquid threads are electrostatically atomized to form charged paint particles.

By the way, when liquid paint is atomized into paint particles and applied to an object to be coated, the quality of the coating film formed on the painted surface is determined by the maximum particle size and average particle size of the paint particles. It is known that when the maximum particle size is large, the quality of the coating film is significantly reduced. Therefore, the rotation speed of the rotating atomizing head has a large effect on the particle size, and the higher the rotation speed of the rotating atomizing head, the smaller the particle size can be, which improves the quality of the coating film. can be done.

However, since the above conventional technology uses ball bearings or roller bearings as a means to support the rotating shaft, the rotation tolerance is limited to 25,000 to 40,000 rpm in order to prevent seizure of these bearings. .
By the way, when the rotational speed of the rotary atomizing head is about 40,000 rpm or less, the average particle size of the paint becomes considerably large, and there is a problem that good paint film quality cannot be obtained.

In order to solve these problems, a static air bearing is used as a bearing to support the rotating shaft without contact, and the rotation speed of the rotating atomizing head is increased to about 60,000 to 100,000 rpm. Kaisho
An electrostatic spraying device as shown in Japanese Patent No. 56-115652 is known.

That is, the electrostatic spraying device according to the above-mentioned prior art includes a housing in which a shaft hole is formed in the axial direction and a turbine chamber is formed in the radial direction on one end side of the shaft hole, and a housing in which a shaft hole is formed in the shaft hole of the housing. a rotating shaft fitted into the housing; a turbine loosely fitted into a turbine chamber of the housing and fixed to one end of the rotating shaft;
a rotating atomizing head located outside the housing and fixed to the other end of the rotating shaft; and a rotating atomizing head located around the rotating shaft and provided on the housing to support the rotating shaft in a non-contact state. The thrust air bearing is generally comprised of a radial air bearing and a thrust air bearing located on both sides of the turbine and provided in the housing to support the turbine in a non-contact manner, and for supplying high pressure air to the turbine. Therefore, the rotating shaft is rotated at high speed, and high-pressure air is supplied to the radial bearing and the thrust bearing to support the rotating shaft, while paint is supplied to the rotating atomizing head and paint particles are atomized from the discharge edge. is being done.

In this way, electrostatic spraying devices using static pressure air bearings can achieve more than twice the high speed of rotation compared to devices using ball bearings, roller bearings, etc., and also have a smaller housing. be able to.

By the way, the electrostatic spraying device according to the prior art described above is configured as shown in FIG. 1, for example.
That is, there is a housing 101 containing a turbine and thrust and radial static pressure air bearings, and a housing 101 that is rotatably supported by the thrust and radial static pressure air bearings within the housing 101 and is driven by the turbine. The rotating shaft 102 has a rotating shaft 102, and a bell-shaped rotating atomizing head 103 is fixed to the tip of the rotating shaft 102. The head body 105 is composed of a head body 105. And the hub member 10
4 has a liquid contact surface 104A formed therein, and a plurality of paint passages 104B, 104B, . . .
Further, the atomizing head body 105 has a liquid contact surface 10 that thins the paint from each paint passage 104B into a thin film.
5A is formed, the tip of which is a discharge edge 105B. Further, a paint tube 106 is fixed to the housing 101 diagonally, one end of the paint tube 106 is connected to a color change valve 107, which will be described later, and the other end is inserted into the hub member 104 and is connected to the liquid contact surface 104A. It is designed to drip paint.

107 is a color changing valve that supplies paint of A, B,...N colors, air and thinner; 108 is a paint valve; 109 is an on-off valve; 110 is a waste liquid tank; 11
1 is a paint pipe that connects between the color change valve 107 and the paint valve 108; 112 is a paint pipe that connects between the paint valve 108 and the paint tube 106; 113;
A waste liquid pipe connects the paint valve 108 and the waste liquid tank 110, and an on-off valve 109 is inserted in the middle of the waste liquid pipe 113.

When supplying paint to the rotary atomizing head 103, the on-off valve 109 is set to the switching position B for a short time, and the paint valve 108 is set to the switching position B, and then the on-off valve 109 is set to the switching position A, and the color changing valve 107 is set to the switching position B. You only need to supply the paint. Also, paint pipe 1
11, the paint valve 108 is set to the switching position A, and the on-off valve 109 is set to the switching position B, and the paint pipe 111 is cleaned at high speed with high pressure air and thinner from the color change valve 107. Furthermore, when cleaning the paint pipe 112 and rotary atomizing head 103, the paint valve 108 is set to the switching position RO, and these are cleaned at low speed with low-pressure air and thinner from the color change valve 107, and waste liquid is removed from the paint booth. I'm trying to keep it from scattering.

When using the rotating atomizing head 103 having the above-described shape, the rotational speed of the rotating atomizing head 103 can be increased by supporting the rotating shaft 102 with thrust and radial static pressure air bearings. Although the shape of 101 could be made smaller, it still had the following drawbacks.

First, the hub member 104 of the rotating atomizing head 103
In addition, it is necessary to insert the paint tube 106 outside the rotating shaft 102, and since the rotating atomizing head 103 is composed of a hub member 104 and an atomizing head main body 105, the overall shape is or the bell caliber becomes larger. As a result, the spray pattern becomes large, making it unsuitable for so-called flat spraying or spot spraying.

Second, the paint tube 106 is connected to the housing 10
Since it is installed diagonally with respect to 1,
When the electrostatic spraying device is attached to an industrial robot or reciprocator, the paint piping connected to the paint tube 106 gets in the way, making it impossible to paint objects that have narrow areas. It was hot.

Thirdly, since the paint valve 108 is provided outside the housing 101, the paint tube 106
and the paint valve 108 must be connected via a paint pipe 112, and when changing colors, the previous color paint filling the paint pipe 112 is not discharged as waste liquid to the waste liquid collection shroud. must not. For this reason, the shroud is also large enough to cover the rotating atomizing head 103, and a cylinder for expanding and contracting the shroud is also required, which has the drawback of increasing the size of the waste liquid recovery mechanism.

Fourth, the rotating atomizing head 103 and the paint pipe 112
When cleaning, it is necessary to clean at a low speed, but the disadvantage is that if there is a large amount of previous color paint remaining in the paint pipe, not only a large amount of thinner is required, but also the cleaning time becomes longer.

Fifth, although there is a small gap between the rotating shaft 102 and the housing 101, as mentioned above, a large amount of thinner must be used during cleaning.
Thinner scattered on the shroud infiltrates into the housing 101 through the gap, and the waste liquid impregnates the static pressure air bearing in the housing 101, causing clogging of the porous bearing member that makes up the air bearing. This has the drawback of shortening the life of the air bearing.

Furthermore, sixthly, in the prior art described above, a high voltage cable is connected to the housing 101 which remains exposed to the outside, and a high voltage is connected from the housing 101 to the rotating atomizing head 103 via the rotating shaft 102. Since the housing 101
It is not possible to manually hold and paint. For this reason, this type of electrostatic coating equipment uses an insulating support member (insulating support) inside the coating booth.
The disadvantage is that the reciprocator must be attached to the reciprocator via the paint booth, and the painting work must be carried out in an unattended atmosphere inside the paint booth.

On the other hand, in the painting process at an automobile factory, an electrostatic spraying device is attached to the end of the arm of an industrial robot in order to automatically paint automobile bodies transported on a conveyor line. Painting is in progress.
However, the above-mentioned rotating atomizing head type electrostatic spraying device not only has a large shape and weight, but also has its housing and rotating atomizing head directly charged with a high voltage, so it is difficult to prevent accidents. The problem is that it cannot be installed on industrial robots. Therefore, for safety reasons, electrostatic spray guns with air atomization type corona pins have been used for this type of industrial robots, but due to their atomization ability, they cannot be used for high viscosity paints. The drawback was that I couldn't do it.

The present invention was devised in view of the drawbacks of the prior art described above, and includes electrically insulating the housing portion and the rotating atomizer head with an insulating cover, and inserting the paint tube into the rotating shaft. By directly providing the paint valve and high voltage cable connection member on the cover, the diameter of the rotating atomizing head and the overall shape of the housing can be reduced, and electrical safety is improved, making it ideal for industrial robots and reciprocating robots. The object of the present invention is to provide an electrostatic spraying device that can be easily attached to a container.

In order to achieve the above object, the features of the configuration adopted by the present invention include covering the entire housing and
A cover made of insulating material is provided to cover the entire rotating atomizing head with only the discharge edge being atomized, and a A paint tube is inserted through the cover in a non-contact state, and a paint valve is provided on the rear end side of the cover to control the paint supplied to the paint tube, and the tip side of the paint tube is connected to the rotary atomizing head. A high voltage cable connecting member is provided at the rear end side of the cover, which is opened toward the center of the back of the partition plate provided halfway through the surface, and is connected to a high voltage cable to apply a high voltage to the housing. It is in.

Hereinafter, the present invention will be described in detail based on the embodiments shown in FIGS. 2 to 5.

In the drawings, reference numeral 1 denotes a cylindrical housing made of a metal body, and the housing 1 has a shaft hole 2 penetrating through it in the axial direction, and a circular turbine chamber 3 in the radial direction at one end of the shaft hole 2. Further, one end side of the housing 1 is an annular groove 1A in which a flange for fixing a paint tube, which will be described later, is seated. 4 is a rotating shaft made of a metal material loosely fitted in the shaft hole 2 with a small gap in the radial direction, and 5 is a rotating shaft in the turbine chamber 3 with a small gap in the axial direction with respect to the turbine chamber 3. The turbine 5 is a disk-shaped turbine made of a metal material that is loosely fitted with a gap such that the turbine 5 is fixed to one end of the rotating shaft 4 by means such as welding or bolts. A large number of blades 5A, 5A, . . . are provided at equal intervals on the outer peripheral surface.

Reference numeral 6 denotes a rotating atomizing head located outside the housing 1 and fixed to the other end side of the rotating shaft 4. In the case of this embodiment, the rotating atomizing head 6 is a cylindrical or bell-shaped atomizing head. It will be done. The rotary atomizing head 6 has a threaded portion 6A for fixing it to the rotating shaft 4, a conical liquid contact surface 6B that expands toward the front in order to thin the paint into a thin film, and a liquid contact surface 6B that widens forward. An edge-shaped discharge edge 6C formed at the tip of the surface 6B, an annular convex portion 6D for preventing backflow of paint and protruding radially inward between the threaded portion 6A and the liquid contact surface 6B, A partition plate 6E provided in the middle of the liquid level 6B, and a large number of paint outlet holes 6 located near the circumferential surface of the partition plate 6E.
F, 6F, . . . , and a large number of grooves are carved in the discharge edge 6C as necessary.

Reference numeral 7 denotes a radial air bearing located around the rotating shaft 4 and disposed in the housing 1 to support the rotating shaft 4 in a non-contact state with respect to the shaft hole 2; Housing 1 to surround the outer periphery of
sleeve-shaped bearings 8, 8 made of a porous metal material such as sintered metal, and an air chamber 9 formed in the housing 1 concentrically with the shaft hole 2, located on the outer peripheral surface of the bearing 8. It is composed of. and,
The air bearing 7 constitutes a static pressure air bearing by the bearing 8 and the air chamber 9, and rotates by blowing out high pressure air supplied to the air chamber 9 from the bearing 8 in the direction of the arrow in the figure, as will be described later. The shaft 4 can be supported in a non-contact manner.

Further, reference numerals 10 and 10 denote thrust air bearings disposed in the housing 1 and located on both sides of the turbine 5 in order to support the turbine 5 in a non-contact state with respect to the turbine chamber 3. A ring-shaped bearing 11 made of a porous metal material such as sintered metal is fixed to the housing 1 so as to sandwich both sides of the turbine 5, and an air bearing 11 formed in the housing 1 is located on the back side of the bearing 11. It consists of a chamber 12. Each of the air bearings 10 also constitutes a static pressure air bearing with a bearing 11 and an air chamber 12.
The turbine 5 can be supported in a non-contact manner by blowing out the high-pressure air supplied to the turbine 2 in the direction of the arrow in the figure.

Next, a paint tube 13 is inserted into the rotating shaft 4 without contacting the rotating shaft 4, and a paint passage 14 is formed in the paint tube 13. A paint tube fixing flange 15 is fixed to one end of the paint tube 13.
5 is fitted into the annular groove 1A of the housing 1, and is fixed by being clamped in cooperation with a cover which will be described later. Further, a nozzle 16 whose tip protrudes from the inner circumferential surface of the liquid contact surface 6B of the rotating atomizing head 6 is fixed to the other end of the paint tube 13, and paint is sprayed from the nozzle 16 toward the center of the back surface of the partition plate 6E. I'm starting to do that.

Reference numeral 17 denotes a turbine driving air passage formed in the housing 1. One end of the air passage 17 is opened at the end surface of the housing 1 so as to be connected to a pressure source through a cover described later, and the other end is connected to the turbine chamber. 3
Inside, a nozzle opening is opened toward the front surface of the blade 5A of the turbine 5. Here, by injecting the high-pressure air supplied to the turbine drive air passage 17 toward the blades 5A of the turbine 5, the turbine 5 is moved together with the rotating shaft 4 and the rotating atomizing head 6.
It can rotate at high speeds of 60,000 to 100,000 rpm. Also, 1
Reference numeral 8 denotes a bearing air passage formed in the housing 1. One end of the air passage 18 is also opened at the end face of the housing 1 so as to be connected to a pressure air source via a cover to be described later, and the other end is branched. Each air chamber 9,1
2 are connected to each other. Further, reference numeral 19 denotes an exhaust passage, one end of which is located between the radial air bearing 7 and the thrust air bearing 10 and opens into the shaft hole 2, and the other end opens into the outer peripheral surface of the housing 1. There is.

Furthermore, 20 is a cover that covers the entire housing 1 and the entire rotary atomizing head 6 with only the discharge edge 6C exposed to ensure safety against high voltage; the cover 20 covers the housing 1. It is composed of a cover body 21 and a front cover 22 screwed onto the front end side of the cover body 21 to cover the rotary atomizing head 6. Both the cover body 21 and the front cover 22 are made of insulating material such as synthetic resin. It is made of wood.

Here, the cover body 21 is formed with a bottomed concave housing accommodating portion 21A, and the housing 1 is fitted into the accommodating portion 21A and fixed to the cover body 21 by bolts 23, 23. In order to ensure safety, the tips of the bolts 23 do not penetrate through the cover body 21, and therefore are not exposed to the outside. Further, a mounting hole 25 is formed on the rear end surface side of the cover body 21 for mounting the present electrostatic spraying device to the arm 24A of the industrial robot 24 or a reciprocator (not shown).

On the other hand, the front cover 22 consists of a large diameter hole 22A, a medium diameter hole 22B, and a small diameter hole 22C.
The inner periphery of the cover body 21 is screwed onto the front end of the cover body 21, and an annular air chamber 26 is formed by the large diameter hole 22A, the housing 1, and the end face of the cover body 21. In addition, large diameter hole 22A and medium diameter hole 22B
In the step wall 22D between the
... are bored, and an air chamber 28 communicating with the air passage 27 is formed between the medium diameter hole 22B and the end surface of the housing 1. Further, the rotary atomizing head 6 is accommodated in the small diameter hole 22C with a slight gap, and only the discharge edge 6C of the rotary atomizing head 6 protrudes from the small diameter hole 22C. The annular gap between the rotating atomizing head 6 and the small diameter hole 22C serves as a shaping air jetting gap 29.

Next, 30 is a paint valve mounting hole formed in the cover body 21, 31 is a paint valve fixed to the paint valve mounting hole 30 via a bolt, and the paint valve 31 is connected to the valve casing valve 31A and the valve casing. A cylinder 31B formed inside 31A, a movable bulkhead 31C slidably fitted into the cylinder 31B, a valve body 31E fixed to the movable bulkhead 31C and seated on and off the valve seat 31D, and the valve body 31E. Retainer 3 that guides
1F and a movable bulkhead 31C within the valve casing 31A.
A pressure chamber 31G and a spring chamber 31H defined by
, a control air port 31I that supplies control air to the pressure chamber 31G, a spring 31J tensioned in the spring chamber 31H to bias the valve body 31E toward the valve seat 31D, and a spring 31J that is tensioned in the spring chamber 31H to bias the valve body 31E toward the valve seat 31D. A paint inflow port 31K is formed in the valve casing 31A so as to be in constant communication even when the valve casing is seated.
The waste liquid discharge port 31L and the valve body 31E are connected to the valve seat 31.
A paint outflow port 31M that allows paint to flow out from the paint inflow port 31K when the paint exit port 31K is removed from the paint inlet port 31K.

Here, the paint inflow port 31K of the paint valve 31 is connected to the paint inflow joint 33 via the paint passage 32, the waste liquid discharge port 31L is connected to the waste liquid discharge joint 35 through the waste liquid discharge passage 34, and the paint outflow port 31M communicates with the paint passage 14 in the paint tube 13 via an L-shaped paint passage 36 formed in the cover body 21. On the other hand, the control air port 31I is connected via a control air passage 37 to a control air joint 38 connected to a pressure air source (see FIG. 4).

Reference numeral 39 designates a turbine drive air passage formed in the cover body 21, one end of which is connected to the turbine drive air passage 17, and the other end connected to a turbine drive air joint 40 connected to a pressure source. There is. A bearing air passage 41 is also formed in the cover body 21, and one end of the air passage 41 is connected to the bearing air passage 18, and the other end is connected to a bearing air joint 42 connected to a pressure source. 43 is a shaping air passage extending in the axial direction of the cover member 21, one end of the shaping air passage 43 is connected to the air chamber 26, and the other end is connected to the shaping air joint 4 connected to the pressure air source.
4 is connected. Reference numeral 45 denotes an exhaust passage extending in the radial direction of the cover body 21. One end of the exhaust passage 45 is connected to the exhaust passage 19, and the other end is connected between the ring-shaped member 46 fixed to the cover body 21 and the cover body 21. An annular exhaust passage 47 formed in
The annular exhaust passage 47 is connected to the atmosphere, and the annular exhaust passage 47 is open to the atmosphere.

Furthermore, 48 is a high voltage cable connecting member provided on the cover body 21, a high voltage cable 49 is attached to the connecting member 48, and one end of the high voltage cable 49 is connected to a high voltage generator (not shown). The other end is in direct contact with the outer periphery of the housing 1. A high voltage of -60 to -120 [kV] generated by the high voltage generator is supplied to the housing 1 via a high voltage cable 49.

In Fig. 5, 50 is a color change valve that supplies A, B,...N color paint, thinner, and air, 51 is a paint pipe that connects the color change valve 50 and the paint inflow joint 33, and 52 is a waste liquid. Discharge joint 35 and waste liquid tank 53
A waste liquid pipe 54 connects between the paint valve 31 and
An on-off valve provided in the middle of the waste liquid pipe 52 is shown in the vicinity of the drain pipe 52.

The present embodiment is constructed as described above, and its operation will now be described.

First, high pressure air is supplied from the bearing air joint 42 to the air chambers 9, 12 of each air bearing 7, 10 through the bearing air passages 41, 18, and
High pressure air is blown out in the direction of the arrow in the figure. As a result, the rotating shaft 4 is held in a non-contact state in the radial direction by the radial air bearing 7, and the turbine 5 is held in a non-contact state in the axial direction by the thrust air bearing 10.

In this state, when high pressure air is supplied from the turbine drive air joint 40 to the front surface of the blades 5A of the turbine 5 through the turbine drive air passages 39 and 17, the turbine 5 is It rotates at high speed. During this time, each air bearing 7, 10
Most of the exhaust gas from the turbine 5 is discharged into the atmosphere through the exhaust passages 19 and 45 and the annular exhaust passage 47. In addition, a part of the exhaust gas flows into the air chamber 2 from the minute gap between the shaft hole 2 of the housing 1 and the rotating shaft 4.
It is discharged within 8 days.

On the other hand, the high voltage cable 49 from the high voltage generator
When a high voltage of, for example, -90 [kV] is supplied to the cable, the housing 1 made of a metal material and in contact with the high voltage cable is charged to -90 [kV]. At this time, the rotating shaft 4 and the turbine 5 are in a non-contact state with respect to the housing 1, but the rotating shaft 4 is loosely fitted into the shaft hole 2 with a small gap, and the turbine 5 is also loosely fitted into the shaft hole 2. It is merely loosely fitted into the turbine chamber 3 with a small gap. As a result, when the housing 1 is charged to a high voltage, the minute air layer interposed between the shaft hole 2 and the rotating shaft 4 and between the turbine chamber 3 and the turbine 5 causes dielectric breakdown. However, due to the discharge phenomenon, the rotating shaft 4 and the turbine 5 are charged to -90 [kV]. Thus, the rotating atomizing head 6
The rotating shaft 4 will also be charged to this high voltage.

On the other hand, when control air is not being supplied to the paint valve 31 from the control air joint 38, the valve body 31E is seated on the valve seat 31D by the spring force of the spring 31J. On the other hand, the on-off valve 54 is left open. In this state, when paint of color A is supplied from the color change valve 50, the color A paint from the paint pipe 51 passes through the paint inflow joint 33 and the paint passage 32 to the paint valve 31.
Paint inlet port 31K, waste liquid discharge port 31
L, further flows toward the waste liquid pipe 52 via the waste liquid discharge passage 34 and the waste liquid discharge joint 35,
These fill the interior. After that, the on-off valve 54 is closed.

Next, in order to supply paint to the rotary atomizing head 6, the control air port 31I of the paint valve 31 is connected to the pressure chamber 31G via the control air passage 37 from the control air joint 38.
supply control air to. As a result, the piston 31
C is displaced upward in FIG. 4 together with the valve body 31E against the spring 31J, causing the valve body 31E to separate from the valve seat 31D. As a result, the paint from the color change valve 50 is supplied from the paint outflow port 31M of the paint valve 31 to the nozzle 16 via the paint passages 36 and 14, and is ejected toward the liquid contact surface 6B of the rotary atomizing head 6. . As a result, the centrifugal force generated when the rotating atomizing head 6 rotates at high speed forms an extremely thin film, which is sprayed as liquid threads from the discharge edge 6C of the rotating atomizing head 6, and is electrostatically atomized to become charged paint particles. . The paint particles fly along the electric lines of force formed between the rotary atomizing head 6 and the object to be coated, and are applied to the object to be coated.

During this time, the spray pattern tends to expand due to the centrifugal force of the rotating atomizing head 6, the air pumping phenomenon, and the like. Therefore, air is supplied to the shaping air joint 44, and the shaping air is jetted from the shaping air jetting gap 29 through the shaping air passage 43, the air chamber 26, the multiple air passages 27, and the air chamber 28 in order to form a pattern.

Next, in order to spray the next color paint, for example, the B color paint, it is necessary to clean all the areas to which the A color paint has adhered. Therefore, the supply of control air to the paint valve 31 is stopped, and the valve body 31E is supplied by the spring 31J.
is seated on the valve seat 31D, and the on-off valve 54 is opened. Then, air and thinner are sequentially supplied from the color change valve 50 to clean the paint pipe 51, the paint passage 32, the paint inlet port 31K of the paint valve 31, the waste liquid discharge port 31L, the waste liquid discharge passage 34, etc., and the thinner waste liquid is disposed of as waste liquid. The liquid is discharged into a waste liquid tank 53 via a pipe 52 and an on-off valve 54. At this time, high-speed cleaning can be performed by supplying air and thinner at high pressure.

Next, in order to clean the valve seat 31D of the paint valve 31, the paint outflow port 31M, the paint passages 36, 14, the rotary atomizing head 6, etc., control air is again supplied to the pressure chamber 31G, and the valve body 31E is At the same time, the on-off valve 54 is closed. Then, air and thinner are sequentially supplied to these interiors at low pressure from the color change valve 50 to perform cleaning. At this time, cleaning is performed while rotating the rotary atomizing head 6, but if the rotation is too fast, the waste liquid will scatter around, so the rotation speed of the rotary atomizing head 6 is set at 5000 to 10000 rpm.
shall be.

After all cleaning is completed, paint with B color can be applied in the same manner as described above.

In this embodiment, the housing 1 is fitted into the housing accommodating part 21A of the cover main body 21 to maintain insulation, and the rotating atomizing head 6 is fitted into the small diameter part 22C of the front cover 22. It is inserted with a shaping air ejection gap 29, and only its ejection edge 6C protrudes slightly from the small diameter hole 22C.

Therefore, since the housing 1 and the rotary atomizing head 6, except for the discharge edge 6C, are covered by the cover 20 consisting of the cover body 21 and the front cover 22, the electrostatic spray according to the present invention There is no danger even if the device is held by hand, and the cover body 21 can be held by the arm 24A of the industrial robot 24.
Even if the housing 1 is installed and painted,
There is no risk that the rotary atomizing head 6 will come into contact with the object to be coated,
Safety can be greatly improved.

On the other hand, in this embodiment, the paint tube 13 can be inserted into the rotating shaft 4, which is the center of rotation, in a non-contact state, and the nozzle 16 can be positioned at the center of the rotating atomizing head 6. Therefore, when a thrust or radial static air bearing is used as a bearing, in addition to the advantage that the shape of the housing 1 can be made smaller compared to when using a ball bearing or a roller bearing, the present invention also has the advantage that the housing 1 can be made smaller in size. Since the paint tube 13 is inserted through the rotary shaft 4 in a so-called "center feed system", the shape of the housing 1 can be further reduced in size and weight. From these points, the present invention can have an overall length of about 11 cm and a weight of about 1.4 kg, so it can be attached to the end of an industrial robot's arm and can perform teaching and playback operations. This can be done with high precision.

Further, the nozzle 16 is connected to the liquid contact surface 6B of the rotating atomizing head 6.
Since the opening can be made approximately at the center of the
Compared to the conventional rotary atomizer head as shown in the figure, the shape of the rotary atomizer head 6 can be simplified and its diameter can be made smaller, improving cleaning performance and making it easier to blow flat surfaces. It can also be applied to spot blowing, etc.

On the other hand, the cover body 21 made of the above-mentioned insulating material
A paint valve 31 is attached to the paint valve 31, and the paint valve 31 connects to the paint passage 14 in the paint tube 13 described above via a paint passage 36 also formed in the cover body 21.
Since the rotary atomizing head 6 and the paint valve 31 are configured to communicate with each other, the distance between the rotary atomizing head 6 and the paint valve 31 can be made as short as possible. As a result, the system path consisting of the color change valve 50, the paint pipe 51, the paint passage 32, the paint inlet port 31K in the paint valve 31, the waste liquid discharge port 31L, the waste liquid pipe 52, the on-off valve 54, etc. is a high-pressure cleaning section. While cleaning can be done in a short time using air and thinner, low-pressure air and thinner are used to clean only the area between the paint valve 31 and the paint passages 36, 14, which are extremely short distances, and the rotary atomizing head 6 as a low-speed cleaning section. You can wash it with Therefore, not only can the cleaning time be significantly shortened, but also the amount of waste liquid flowing out from the rotary atomizing head 6 is small, so it is not necessary to provide the rotary atomizing head 6 with a waste liquid recovery shroud as in the prior art. The structure can be simplified.

In addition, the annular convex portion 6D of the rotating atomizing head 6 and the nozzle 1
Although there is a small gap between the rotating shaft 4 and the rotary atomizing head 6, as described above, the amount of waste liquid flowing out from the rotating atomizing head 6 can be reduced to a small amount.
There is no risk of waste liquid flowing out into the gap between the paint tube 13 and the shaft hole 2, or into the gap between the shaft hole 2 and the rotating shaft 4. Therefore, the air bearings 7, 10, etc. are not damaged by the waste liquid, and the life of these air bearings 7, 10 can be extended.

Furthermore, since the paint valve 31 is provided on the rear end side of the cover body 21, there is no need for a paint tube or paint pipe to extend near the rotary atomizing head as in the prior art. It can also be applied to objects, and is particularly suitable for use by being attached to the arm 24A of the industrial robot 24.

In this embodiment, the rotary atomizing head 6 is illustrated as being cylindrical or bell-shaped, but a disk-shaped or circular plate-shaped one may also be used. Furthermore, although the cover 20 described above has been described as consisting of the cover body 21 and the front cover 22, this is a matter of assembly or workmanship, and the cover 20 may have any shape. Further, the paint valve 31 is not limited to the illustrated three-way opening type, and various valve types can be adopted. Furthermore, the object to which the present invention is applied is not limited to paint spraying equipment, but may also be applied to spray granulation equipment, spray drying equipment, flash drying equipment, etc.

The electrostatic spraying device according to the present invention is as described in detail above, and the entire rotating atomizing head is covered with an insulating cover while only the entire housing and the discharge edge are exposed. A paint tube is inserted into the housing without contacting the rotating shaft, and a paint valve is provided at the rear end of the cover to control the paint supplied to the paint tube. Since the voltage cable connection member is provided, the housing and rotating atomizing head are miniaturized, and since the paint tube and high voltage cable are not located near the rotating atomizing head, they do not get in the way during painting work. It is suitable as an electrostatic spray device for industrial robots and reciprocators. In addition, the paint valve that supplies paint to the rotating atomizing head is installed directly on the rear end of the cover, and the distance between it and the rotating atomizing head is shortened as much as possible, reducing cleaning time. This not only eliminates the need for a waste liquid recovery shroud, but also reduces the amount of waste liquid that flows out from the rotating atomizer head, allowing the waste liquid to enter the housing through gaps between the rotating shaft and the paint tube, and prevent air from entering the housing. The life of the bearing will not be shortened.
Furthermore, since the high voltage cable connection member is provided on the rear end side of the cover and high voltage is directly applied to the housing, and the housing and rotating atomizing head are covered with an insulating cover, the electrostatic spraying device Even when the robot is attached to an industrial robot to perform teaching operations, it has many effects such as ensuring safety.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the main part of an electrostatic spraying device according to the prior art, including the paint system, and Figs. 2 to 5 relate to the electrostatic spraying device according to the present invention; Figure 3 is the left side view of Figure 2, Figure 4 is the left side view of Figure 2.
FIG. 5 is a cross-sectional view of the main part taken along the - line in the figure, and FIG. 5 is a diagram showing how the paint system is installed on an industrial robot. DESCRIPTION OF SYMBOLS 1... Housing, 2... Shaft hole, 3... Turbine chamber, 4... Rotating shaft, 5... Turbine, 6... Rotating atomization head, 7... Radial air bearing, 10... Thrust bearing, 13 ...Paint tube, 14,3
2, 36... Paint passage, 17, 39... Turbine drive air passage, 18, 41... Bearing air passage, 19, 45... Exhaust passage, 20... Cover,
21...Cover body, 22...Front cover, 30
...Paint valve mounting hole, 31...Paint valve, 34...Drainage discharge passage, 37...Control air passage, 43...Air passage for shaping air, 49...High voltage cable.

Claims (1)

[Scope of utility model registration request] A housing having a shaft hole formed therein in the axial direction and a turbine chamber formed in the radial direction at one end of the shaft hole, a rotating shaft loosely fitted in the shaft hole of the housing, and a turbine chamber of the housing. a turbine loosely fitted into the housing and fixed to one end of the rotating shaft; and a rotating atomizing head located outside the housing and fixed to the other end of the rotating shaft and having a discharge edge at the tip of the liquid contact surface. a radial air bearing located around the rotating shaft and provided in the housing to support the rotating shaft in a non-contact manner; and both side surfaces of the turbine to support the turbine in a non-contact manner. and a thrust air bearing located in the housing, which covers the entire housing and covers the entire rotating atomizing head with only the discharge edge exposed. A cover made of an insulating material is provided, a paint tube is inserted into the rotating shaft in a non-contact state with respect to the rotating shaft, and a rear end side of the cover controls the paint supplied to the paint tube. A paint valve is provided, the tip side of the paint tube is opened toward the center of the back of the partition plate provided midway through the liquid contact surface of the rotary atomizing head, and a high voltage cable is connected to the rear end of the cover. An electrostatic spraying device characterized in that a high voltage cable connecting member is connected to apply a high voltage to the housing.