KR20030004018A - Apparatus and method for powder coating - Google Patents

Abstract

PURPOSE: To eliminate heat ununiformity in a coating apparatus by which a powder coating is baked and dried by a high frequency induction coil. CONSTITUTION: Two high frequency induction coils 51 and 51' independent from each other are arranged facing each other across a transfer passage of a hanger 5 and the distance between the coils 51, 51' and a material to be coated is controlled by moving a coil case 52 housing the coils 51 and 51' with a stepping motor 50. The control data of the control items such as the heating time by the coils 51 and 51' and the like is recorded in SID-TAG 88 in every hangers 5 and the coating of the material 3 to be applied on the hanger 5 is automatically controlled according to the control data. Then, the baking and drying are performed at a uniform temperature without the occurrence of the partial difference in the intensity of high frequency induction because bending parts in the high frequency induction coil are not formed. The control of the temperature or the like is automatically carried out in every material 3 to be coated, which is made as the unit of the hanger 5.

Description

Powder coating device and powder coating method {APPARATUS AND METHOD FOR POWDER COATING}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder coating apparatus or a powder coating method capable of forming a uniform coating film without spots even on a workpiece (workpiece) having a complicated shape, for example, a steel pipe joint. The present invention relates to a powder coating apparatus and a powder coating method which improve the adhesion to the workpiece and omit the degreasing step, thereby making the painting work more efficient and further increasing the productivity.

(Conventional technology)

The conventional coating method first performs degreasing treatment to remove foreign matters such as fats and oils adhered to the surface of the coated object to be coated, and then goes through washing, draining, and drying to perform coating, drying, baking by far-infrared irradiation, Each process of cooling was performed.

However, dry baking by far-infrared irradiation heats the paint externally, and therefore, particularly to be coated with a complicated shape, the baking surface is excessively baked on the paint surface, and the paint fixing surface tends to be insufficient in baking. It was happening. Moreover, the dry baking by far-infrared irradiation has a drawback which takes time to dry. In addition, when uniform drying is to be performed by far-infrared irradiation, the apparatus becomes large, which makes it difficult to secure the installation space and increases the equipment cost.

Moreover, in the above-mentioned conventional coating method, it is necessary to perform the degreasing process of a to-be-coated object before coating. This is because in the case of heating from the outside by far-infrared irradiation, when foreign matter such as oil or fat is interposed at the interface between the coated object and the coating film, adhesion is insufficient and peeling of the coating film occurs.

However, it is considered natural to perform the degreasing treatment on the entire individual coated object, which is very complicated, which greatly hinders the efficiency of the painting work.

In the case of coating the object to be coated, a hanger for holding a large number of objects to be coated is used. As the coating is repeatedly performed, scattered surplus paint adheres to the hanger and is heated and firmly adhered to it. Ancillary work of peeling excess paint was needed.

The present invention allows the formation of a uniform and firm coating film without spots in consideration of the problems of the conventional technology, and furthermore, the coating of a new and useful coating material which further miniaturizes the device and makes the painting work more efficient. It is an object of the present invention to provide an apparatus and to establish a coating method for a coated object.

1 is an internal perspective perspective view of a powder coating apparatus according to a first embodiment of the present invention;

2 is a plan view of the powder coating apparatus of FIG.

FIG. 3 is a longitudinal side view showing the inside of a processing unit that performs powder electrostatic coating in the powder coating apparatus of FIG. 1;

4 is a view showing an outline of the powder coating apparatus of FIG.

5 is a plan view showing two types of layouts of a processing unit in a powder coating apparatus according to another embodiment of the present invention, wherein the first embodiment of the present invention is modified.

6 is an overall plan view of a powder coating apparatus according to a second embodiment of the present invention;

7 is a perspective view of an essential part of the powder coating device of FIG. 6;

8 is a partially omitted perspective view in which the hanger of the powder coating apparatus of FIG. 6 is enlarged;

FIG. 9 is a perspective view showing a state in which a coated object is suspended from a coated object hook in the powder coating apparatus of FIG. 6;

FIG. 10 is a side view of the powder coating apparatus of FIG. 6, showing a state in which a workpiece is suspended from a workpiece hook; FIG.

11 is an enlarged perspective view of a heating section of a coating booth in the powder coating apparatus of FIG. 6;

12 is an enlarged side view of the heating part of the coating booth in the powder coating apparatus of FIG. 6;

FIG. 13 is an enlarged perspective view of a tag attaching part of a hanger in the powder coating apparatus of FIG. 6;

FIG. 14 is a diagram illustrating a control system of the powder coating apparatus of FIG. 6.

(Explanation of the sign)

1 Powder coating device 3 Work piece (workpiece)

5 working units 7 contact processing units

9 Paint application part 11 Paint application part

13 Drying Process 15 Air Blow Treatment

17 Auxiliary Drying Process 19 Carrier

21 Conveyor conveyor 23 Rotary shaft

25 Rotary arm 27 Arm drive motor

29 Transmission 31 Hanger

33 Reverse Motor 35 Suspension Support Rod

37 Retaining armbar 39 Paint coating

41 Nozzle 43 Recovery

45 Suction Duct 47 High Frequency Induction Heating Equipment

49 High Frequency Induction Coil 51 Slit

53 Induction Heating Power Supply 55 Air Blower

57 Nozzle 59 Far Infrared Lamp

61 Cooling Fan 63 Receiving Treatment

65 Water treatment unit 101 powder coating equipment

103 Coat 105 Hanger

107 Hook Attachment Bar 107a Vertical Groove

108 Workpiece Hook 108a Attachment

108b arm 108c hook

110 Tag mounting 125 Paint application

125 'paint applicator 126 heating part

131 Main shaft 132 Swivel mechanism

133 Hanger Suspension Support Bar 144 Motor for Spray Gun Driving

182 Motor Drive Circuit for Spray Gun

151, 151 'high frequency induction coil

152 Coil Support Base 155 Slide Block

156 Guide rail 157 Nut

158 screw shaft 159 stepping motor

183 Paint Valve 184 Paint Valve Control Circuit

187 coil drive circuit 187a timer

188 Tag 189 Data Readout Circuit

190 Powder P Powder Coating

In order to solve the said subject, invention of Claim 1 is equipped with the coating part which apply | coats powder coating material to the surface of a to-be-coated object, and the heating part which bake-drys the said powder coating material by high frequency induction heating of the to-be-coated object to which the powder coating material was apply | coated. It is a high frequency induction heating powder coating device, characterized in that.

The invention according to claim 2, wherein in the powder coating apparatus according to claim 1, the coating apparatus is provided with a hanger for holding the object to be coated in a suspended state, and the hanger is formed of a material that is not heated by high frequency. It is a powder coating apparatus characterized by the above-mentioned.

The powder coating apparatus according to claim 3, wherein the powder coating apparatus according to claim 1 is provided with a conveying apparatus having a rotary conveying path for rotating a workpiece on a horizontal circle track.

The invention according to claim 4 is provided with a coating application step of applying a powder coating on the surface of the coated object, and a high frequency induction heating step of baking and drying the powder coating from the inside by induction heating of the coated object coated with the powder coating. It is a high frequency induction heating powder coating method characterized by the above-mentioned.

In the powder coating apparatus of Claim 1, the powder coating apparatus of Claim 1 bake-drys the said powder coating material by the high frequency induction heating of the coating part which apply | coats powder coating material to a to-be-coated object, and the to-be-coated object to which this powder coating material was apply | coated. A high frequency induction heating powder coating device comprising a plurality of processing units including a heating unit, a hanger having a workpiece hook attached to a substantially horizontal hook attachment bar, and a hanger transfer unit for sequentially transferring the hangers to the plurality of processing units. The workpiece hook has a shape having an attachment portion bent in a substantially inverted U shape and an arm extending from one end of the attachment portion, and the hook attachment bar has a plurality of vertical grooves for attaching and detaching the attachment portion freely. High frequency induction heating powder coating device, characterized in that formed in the direction.

In this coating device, the workpiece hook is mounted on the hook attachment bar by selecting an arbitrary longitudinal groove of the hook attachment bar and walking the attachment portion therein, and the attached position is engaged with the attachment groove in the vertical groove. By doing so, it can be stably held and can be detached from the hook attachment bar simply by pulling the attachment portion in that state.

Therefore, since the attachment and detachment of the workpiece hook to the hook attachment bar ends in almost one operation, the shape and size of the workpiece to be applied are determined according to the type, number, and intervals of attachment of the workpiece to be attached to the hook attachment bar. This can be done in a short time, either in accordance with the replacement or in order to adjust the opposing distance to the high frequency induction coil.

The workpiece hook may be produced by processing a wire rod such as phosphor bronze, which is not adhered to the powder coating material, and when the attachment portion is formed in a clip shape, the spring elasticity of the clip in the hook attachment bar is increased. By doing so, the attachment position can be kept more stable.

In the powder coating apparatus of Claim 5, the powder coating apparatus of Claim 5 WHEREIN: The attachment part and the arm of a to-be-coated workpiece hook are formed of the cross-section circular wire rod, and the tip end of the arm is a position lower than the attachment part to some extent. It extends and attaches the arrowhead type hook part for suspending to-be-coated object to the front end, The powder coating apparatus characterized by the above-mentioned.

Therefore, if the height dimension of the arm of the workpiece hook is slightly longer than the dimension from the hook hole to the upper end of the workpiece to be hung on this, the workpiece hung on the workpiece hook is viewed from the front and rear direction, Since the whole is located below the hook attachment bar, the hook attachment bar does not interfere with paint spraying from the rear side. In addition, since the attachment portion and the arm of the workpiece hook are formed of a wire rod, the width is very small, so that the spraying of the paint on the rear side is hardly prevented. By these, the coating stain of paint can be eliminated.

The powder coating apparatus according to claim 1, wherein the powder coating apparatus according to claim 1 is baked and dried by applying a high frequency induction heating to a coating application unit for applying the powder coating to the coated object and a coated object to which the powder coating is applied. And a hanger having a workpiece hook attached to a substantially horizontal hook attachment bar, and a hanger transfer means for sequentially transferring the hanger to the plurality of treatment units. It is a powder coating device, characterized in that the two arranged in the state facing the hanger feed path.

Therefore, since it is not necessary to make a bend in the high frequency induction coil, there is almost no partial difference in the intensity of the high frequency induction, and all the workpieces facing the front face can be uniformly heated.

When carrying out the present invention, the two coils may have a separate structure in a circuit, but when the ends of both coils are connected by a wire rod in a form which does not form a vortex, these structures are integrated in a circuit. The power supply means to the coil can be simplified.

The invention according to claim 8, in the powder coating apparatus according to claim 7, supports two high frequency induction coils on a coil support base which is free to move on the opposite side in the opposite direction thereof, and at the same time, the coil support base. Powder coating device characterized in that the coil position control means for moving the installed.

In this way, the distance between two coils and the opposing space between a coil and a to-be-coated object can be adjusted. For example, when a hanger enters and exits a heating part, two coils may be moved to the position where these spaces widen. At the time of waiting, when heating, control, such as moving a coil to the position which becomes the most opposing space | interval for the to-be-coated object, is possible. Thereby, the size of the to-be-coated object becomes large, versatility becomes high, and it can implement | achieve setting optimum heating conditions for every to-be-coated object.

The invention according to claim 9 is the powder coating apparatus according to claim 8, wherein the tag is attached to a hanger and records position control data or surrogate data of two high frequency induction coils, and data reading for reading the data recorded on the tag. And a processing unit for generating a control signal based on the data read by the data reading circuit, and a control circuit for controlling the position of the coil based on the control signal.

Therefore, according to the invention of claim 9, the position of the high frequency induction coil, which is one of the control items for realizing optimal heating according to the characteristics of the object to be coated or the paint, on the object to be coated is controlled beforehand. It is automatically adjusted by writing the tag.

The powder coating apparatus according to claim 1, wherein the powder coating apparatus according to claim 1 is baked and dried by applying a high frequency induction heating to a coating part for applying the powder coating to the coated object and a coated object to which the powder coating is applied. A plurality of processing units including a heating unit, a hanger with a large number of workpiece hooks attached to at least the up and down direction, hanger conveying means for sequentially transferring the hangers to the plurality of processing units, attached to the hanger, and control data or proxy On the basis of the tag in which the data is written, the data reading circuit for reading the data recorded in the tag, the data read out by the data reading circuit, the number of movements of the spray gun, the amount of powder coating sprayed from the spray gun, and the high frequency induction coil A processor for generating a control signal for at least one control item during the heating time by And a control circuit for controlling the control item.

According to the invention of claim 10, the number of movements of the spray gun, which is a control item for achieving optimum coating or heating depending on the characteristics of the object to be coated or the coating, the amount of injection of the powder coating from the spray gun, or the heating time by the high frequency induction coil At least one of the control is automatically adjusted by recording the control data or the surrogate data in a tag in advance.

Therefore, in the invention according to claim 9 or 10, one or more control items relating to the quality of coating or baking drying are automatically controlled under optimum conditions depending on the type of coating material or the coating material used therein. In this way, an inefficient process of changing the control content is unnecessary, such as stopping the line operation and adjusting the position of the high frequency induction coil every time the lot of the workpiece to be applied differs.

In particular, in these inventions, since the control data or the surrogate data is provided for each hanger, even a small amount of lot can be painted under optimum processing conditions at that time.

As the data recording method according to the invention of claim 9 or 10, a method of directly recording control data into a tag, and specific control data are stored in advance in a data file for each object to be coated, and the tag includes the part number of the object to be coated. A method of recording only the surrogate data is considered. If the so-called SID-TAG system or the like is used for the system of this tag, the latter method may be used.

Embodiment of the Invention

Hereinafter, the powder coating apparatus 1 which concerns on 1st Embodiment is demonstrated according to FIGS.

The powder coating apparatus 1 of this invention is used, for example, when apply | coating to the steel to-be-coated object 3 which has a complicated shape like iron pipe joints.

Specifically, as shown in Figs. 1 and 2, the interior of the cylindrical container-shaped work part 5 is divided into six processing parts 7, 9, 11, 13, 15, and 17 as an example, and then each processing part 7 again. , 9, 11, 13, 15, and 17 are configured to include an auxiliary device for individual processing and a conveying device 19 for holding and conveying the object to be coated 3.

Among them, the contact processing unit 7 receives the to-be-coated material 3 conveyed from the outside by the conveying conveyor 21 in the work unit, and after the series of painting work ends, the contact processing unit 7 again delivers the conveying object to the external conveying conveyor 21. It acts as a liaison to the outside. The rotary shaft 23 is provided in the center of the work part 5, and six rotary arms 25 extending radially are provided in the upper part of the rotary shaft 23 as an example.

In addition, rotation of the output shaft of the arm drive motor 27 is transmitted to the rotating shaft 23 through suitable transmission means 29 such as a chain and a timing belt.

On the free end side of the rotating arm 25, a hanger 31 for holding the workpiece 3 in the suspended support state is provided. The hanger 31 is inverted by the inverting motor 33, for example, by 180 degrees. It is configured to rotate.

The hanger 31 is comprised by attaching the some holding arm bar 37 arrange | positioned horizontally at an appropriate space | interval with respect to the suspension support rod 35 installed and received in a perpendicular direction. The hanger 31 is formed of copper as an example of a material which is not heated by high frequency.

The conveying apparatus 19 which added the conveying conveyor 21 to these rotary motion shafts 23, the rotating arm 25, the drive motor 27, the transmission means 29, and the hanger 31 is used.

The paint application part 9 is provided next to the conveyance direction of the communication process part 7, and the paint application part 11 is provided next to it. The paint application part 9 and the paint application part 11 are basically provided in parallel in order to cope with the production of many kinds of small quantities etc. that are basically the same structure. The paint-coating parts 9 and 11 face the nozzle-shaped nozzle 41 of the paint-coating part 39 provided in the exterior of the work part 5, respectively.

The coating application part 39 is an apparatus which apply | coats powder coating material P to the surface of the to-be-coated object 3 using an electrostatic induction action. The powder coating (P) is used here because a solvent is required when a liquid coating is used. However, the solvent is not used because it is a factor such as environmental pollution.

In addition, the suction duct 45 is connected to the paint application parts 9 and 11. This suction duct 45 is connected to the collection | recovery apparatus 43 which collect | recovers the extra powder coating material P which was not used for the application | coating of the to-be-processed object 3 to. Next to the conveyance direction of the coating material applying part 11, the heating part 13 which heats, solidifies, and drys the powder coating material P apply | coated to the surface of the to-be-coated object 3 is provided.

In the heating section 13, the workpiece 3 and the hanger 31, which is a part of the high frequency induction heating apparatus 47, which has a cross section “yo” shaped high frequency induction coil 49, is placed upwardly and conveyed. The slit 51 is provided toward the conveyance direction side so that the () can pass.

The high frequency induction coil 49 receives a current from the induction heating power supply 53, which is another part of the high frequency induction heating apparatus 47, and applies a high frequency current to the object to be coated 3 so that the object to be coated 3 Powder coating P applied to is heated from the inside. Although not shown, in order to prevent excessive heat generation of the high frequency induction coil 49, a conduit for flowing the cooling water is provided in the high frequency induction coil 49.

In the case where the coating film is formed by using high frequency induction heating in this manner, the powder coating material P is heated from the inside to solidify and dry. Therefore, even if a small amount of foreign matter such as oil or fat adheres to the surface of the object to be coated 3, they are vaporized by heat and disappear from the interface between the iron and the coating film, so there is no shortage of adhesion. It becomes unnecessary.

In addition, the hanger 31 is formed of a material which is not heated by high frequency, for example, copper, and the powder coating material P attached to the surface of the hanger 31 is not heated and is maintained as it is. If high pressure air is blown out to the hanger 31, it can remove easily.

Next to the conveyance direction of the heating part 13, the air processing part 15 for brushing off the remaining powder paint P adhering to the to-be-coated 3 and the coating film surface of the hanger 31 is provided. The injection hole 57 of the air blower 55 faces the air processing part 15. Moreover, beside the conveyance direction of the air processing part 15, the auxiliary drying process part 17 which mainly performs the auxiliary heating effect of the surface side of the coating film formed in the to-be-coated object 3 is provided. As an example, a plurality of 2 kw far-infrared lamps 59 are provided in the auxiliary drying treatment unit 17, thereby ensuring solidification and drying of a uniform coating film without spots. In addition, solidification and drying of the coating film by the far-infrared lamp 59 in this auxiliary drying process part 17 are assisted to the last, and solidification by high frequency and drying with respect to most to-be-coated object are enough.

Next to the conveying direction of the auxiliary drying treatment unit 17, a contact processing unit 7 serving as a contact unit with the outside described above is located. The to-be-coated object 3 accommodated in the contact processing part 7 will be in the state in which the coating film was formed in the surface, and is carried out toward the conveyance conveyor 21 located outside. Moreover, the cooling fan 61 is provided in the carrying-out side of the conveyance conveyor 21, and this part also functions as a cooling part. By this cooling fan 61, the to-be-coated object 3 and the coating film are aimed at.

Next, the operation of the powder coating device 1 will be described for each step.

[Covering Process]

The to-be-processed object 3 set to the hanger 31 is accommodated in the communication process part 7 by a suitable conveying apparatus, after conveying a predetermined distance by the conveyance conveyor 21. As shown in FIG. When accommodated in the contact processing section 7, the upper end of the suspension support rod 35 of the hanger 31 is connected to the free end of the rotating arm 25, and the workpiece 3 is moved in a horizontal circle in the work section 5. It becomes possible to move on a conveyance path.

[Paint Coating Process]

The to-be-coated object 3 accommodated in the work part 5 via the contact processing part 7 is rotated by the rotation shaft 23 by predetermined angle, and reaches the paint application part 9 thru | or the coating part 11. In the paint coating parts 9 and 11, the powder coating material P supplied by the paint coating part 39 is sprayed from the nozzle 41, and is apply | coated to the surface of the to-be-coated object 3 by an electrostatic induction action. .

Further, the powder coating P is adsorbed and applied without leaving the surface of the workpiece 3 set on the hanger 31 by being driven by the inversion motor 33 and the hanger 31 being inverted by 180 degrees. On the other hand, the excess powder coating material P which is not adsorbed and coated on the to-be-coated object 3 is collect | recovered by the recovery apparatus 43. FIG.

[High frequency induction heating process]

Next, the to-be-coated 3 moves in the drying process part 13, and is located in the slit 51 formed in the high frequency induction coil 49. As shown in FIG. Here, the high frequency generated from the high frequency induction coil 49 acts on the to-be-coated object 3 by receiving the electric current from the induction heating power supply 53, and heats the to-be-processed object 3. By heating the to-be-coated 3, the powder coating material P apply | coated to the surface of the to-be-coated 3 is heated from the inside, and is provided for coagulation and drying. At the same time, foreign matters such as fats and oils adhered to the surface of the object to be coated 3 are also heated and vaporized to disappear. Since the temperature at which the fat or oil is heated and vaporized is lower than the temperature at which the powder paint P is solidified, even after the powder coating P is applied to the object to be coated 3, the fat or oil vaporized is powder powder before solidification. It is emitted through (P).

In addition, foreign substances such as oils and fats vaporized by heating are adsorbed and filtered by an adsorption filtration device (not shown). As a result, clean air containing no foreign matter is discharged to the outside.

[Air blow process]

The coated film 3 formed by the high frequency induction heating process reaches the air blow processing unit 15, and the remaining powder paint P attached to the surface of the coating film is removed by the air injected from the air blower 55. . At the same time, the powder coating material P attached to the hanger 31 is also removed.

[Auxiliary Drying Process]

Next, the to-be-coated object 3 reaches the auxiliary drying process part 17, is irradiated by the far-infrared lamp 59, and is provided for auxiliary drying, and coagulation | solidification of a uniform coating film without a spot, and perfection of drying are attained.

(Product Export Process)

And the to-be-processed object 3 returns to the communication process part 7 again, and is conveyed toward the external conveyance conveyor 21 through an appropriate conveyance apparatus. The to-be-coated object 3 conveyed to the conveyance conveyor 21 is cooled by receiving the cooling wind by the cooling fan 61 on the way, and is carried out as a product.

In the same manner, the workpiece 3 suspended from the conveying conveyor 21 by the hanger 31 is similarly accommodated in the work part 5 in succession, and is again conveyed to the conveying conveyor 21 through the above-described steps. It is conveyed and carried out.

5 is a figure which drew the outline | summary of the coating device 1 especially, paying attention to a to-be-hooked object, and drawing it again.

The to-be-coated object 3 hangs on the hanger 31, and conveys a coating application part, a heating part, and a cooling part sequentially. As described above, in the paint coating parts 9 and 11, the spray gun f which injects the electrostatically charged powder paint P from the nozzle 41 is installed so as to reciprocate in the vertical direction, and the heating part ( In 13), a high frequency induction coil 49 formed by bending an elliptic vortex coil in a U shape is arranged, and a blowing fan 61 and the like are provided in the cooling unit.

The hanger 31 attaches a plurality of horizontal hook attachment bars i to the vertically long pole h in the vertical direction, and attaches a large number of workpiece hooks j to the hook attachment bars i. It has one structure, and many bolt through-holes k are formed in the hook attachment bar i in the longitudinal direction. The workpiece hook (j) is processed to form an approximately L-shape that is horizontally long with a band plate, and the length of the vertical portion is almost equal to the vertical width of the hook attachment bar (i). Pass the bolt (m) that has passed through one of the bolt through holes (k), and screw the nut (p) to the bolt (m) from the rear of the hook attachment bar (i) to about two to three pieces. It is attached to the arbitrary position of the hook attachment bar (i).

The tip of the horizontal portion of the workpiece hook j is pointed in the form of an arrowhead, and the pointed portion is inserted into the hook hole q of the workpiece 3 to be inserted into the workpiece hook j. Hang the coating (3).

When the hanger 31 comes to the paint application part 9, the spray gun f raises and lowers and sprays powder coating material toward the hanger 31. As shown in FIG. Thereby, the powder coating material P is apply | coated to the to-be-coated object 3 by an electrostatic induction action.

The hanger 31 is then transferred between the left half g-1 and the right half g-2 of the high frequency induction coil 49, where the workpiece 31 suspended from the hanger 31 is suspended. It is heated inside itself. This heating is adjusted so that the temperature of the to-be-coated object 3 may be about 250-280 degreeC. Thereby, the powder coating material P apply | coated to the to-be-coated object 3 is heated previously from the inside, and by this, powder coating material P is baked and dried.

According to the above embodiment, by heating and drying using high frequency induction, heating from the inside of the coating film becomes possible, and in addition to uniform drying without spots, the drying time can be shortened, the device can be downsized, and the like. .

In addition, foreign matters such as fats and oils adhered to the surface of the object to be coated 3 are vaporized and lost at the time of high frequency induction heating. Therefore, degreasing treatment, which is indispensable in the past, is not necessary, and the work efficiency can be drastically improved. have.

In addition, in order to apply | coat using powder coating material P, the solvent required when using liquid coating material P is unnecessary at all, and there is no problem of environmental pollution. In addition, since the hanger 31 is formed of a material which is not heated by high frequency, for example, copper, even if excess paint adheres to the hanger 31, it is not heated or dried. It is possible to simply shake off.

As mentioned above, although 1st embodiment was described above, the scope of the invention is not limited to this embodiment, Even if there exists a design change etc. in the range which does not deviate from the summary of this invention, it is included in this invention.

For example, in the said embodiment, although the process of setting the paint application process 2 steps and installing the paint application parts 9 and 11 of the same structure in parallel was employ | adopted, the paint application process is made into only 1 process, for example, paint It is of course possible to set it as the structure which abbreviate | omits the coating part 11, On the contrary, it is also possible to further expand a coating | coating application part, and to set a coating | coating application process more than three processes.

It is also possible to freely adjust the spacing of the slits 51 of the high frequency induction coil 49. In this way, it is possible to cope with the workpiece 3 of various sizes, and the heating temperature in the high frequency induction heating process. Can be adjusted and uniformized.

In addition, it is also possible to omit the air blow process by the air blower 55, if there is no fear of adhesion of excess powder coating material P on the coating film surface.

In addition, if the uniform coating film without spots can be formed only by the high frequency induction heating step, the auxiliary drying step by the far infrared ray lamp 59 can be omitted.

Moreover, in the said embodiment, although the receipt and water supply of the to-be-coated object 3 to the work part 5 were performed by the one communication process part 7, FIG. 4 (a) which dedicates receipt and water supply, respectively. It is also possible to carry out by the receiving processing part 63 and the water supply processing part 65 as shown in ().

In addition, the conveyance path | route of the to-be-coated object 3 in the work part 5 is not limited to the said embodiment and the rotary type as shown to Fig.4 (a), It can also form linearly, FIG. As shown in (b), it is also possible to use a trolley system.

In addition, the movement of the to-be-applied object 3 is not limited to an intermittent movement, It is also possible to continuously move by varying the magnitude | size of a process part, an action length, etc. In addition, it is also possible to coat parts other than the energization part of the hanger 31 with Teflon etc., and this makes cleaning of the hanger 31, etc. simpler.

Hereinafter, the powder coating apparatus 101 which concerns on 2nd Embodiment of this invention is demonstrated according to FIGS.

This coating apparatus 101 is of the form which arrange | positioned the required process part on the main track | orbit.

The coated object 103 shown in the figure is a steel pipe joint, and the hook hole 103a for painting is formed in the substantially center part. Of course, this to-be-applied object 103 is only what showed an example of the many things which can be processed by the coating apparatus 101. FIG.

[A. Hanger] (FIGS. 6-10, 12, 13)

First, the hanger 105 which hangs and conveys the to-be-coated object 103 is demonstrated (refer FIG. 8 thru | or FIG. 10 for details).

The hanger 105 includes a pole 106 having a vertically long pipe shape, a plurality of hook attachment bars 107 attached to the pole 106 in a state of being arranged at regular intervals in the vertical direction, and the hook. It is composed of a plurality of workpiece hook 108 to be detachably attached to the attachment bar 107, a suspending projection 109 protruding horizontally from the upper end of the pawl 106 to the left and right, and the tag mounting portion 110 Each of these portions is formed of a material which is not subjected to the action of high frequency induction, for example, phosphor bronze.

The hook attachment bar 107 is a strip shape having a relatively narrow width, and is attached so as to protrude horizontally from the pole 106 in a posture in which the width direction thereof becomes the vertical direction. The attachment is hook attachment bar 107. This is done by bending one end of the bolt at a right angle and fixing the bolt.

A plurality of vertical grooves 107a are formed on both sides in the thickness direction of the hook attachment bar 107 at a constant pitch in the horizontal direction. The vertical grooves 107a have a substantially V-shape as viewed in the vertical direction, and the arrangement phase of the vertical grooves 107a on one side and the arrangement phase of the vertical grooves 107a on the other side are coincident with each other.

The hook attachment bar 107 is provided in plural so that two sets of steps projecting from the pawls 106 on the opposite sides are arranged at regular intervals in the vertical direction, and the extension directions of all the steps coincide with each other.

The to-be-hooked object 108 consists of the attachment part 108a and the arm 108b which bended the cross-sectional circular wire rod, and the hook part 108c, and all these materials use phosphor bronze. The attachment portion 108a has a vertically long and long inverted U-shape, and its width is almost the same as the thickness between the two front and rear grooves 107a of the hook attachment bar 107. The arm 108b extends so as to draw an almost quarter arc from the one end of the attachment part 108a toward the front side downward, and the hook part 108c is being fixed to the front-end | tip of this arm 108b. The hook portion 108c is formed to form an arrowhead shape of an almost isosceles triangle, and is attached to the arm 108b by press-fitting and welding the tip of the arm 108b into a hole formed in the side opposite to the vertex angle.

Such a workpiece hook 108 is detachably detached by arbitrarily selecting two front and rear pairs from a plurality of longitudinal grooves 107a formed in the hook attachment bar 107 and walking the attachment portion 108a therefrom. It is attached freely. Therefore, the state where the workpiece hook 108 is attached to the hook attachment bar 107 is positioned and securely held by the attachment portion 108a engaging the longitudinal groove 107a.

The number of the workpiece hooks 108 to be attached to one hook attachment bar 107 usually shows an example in which two to three (two in FIGS. 6 and 7 are attached and three in FIG. 8 are attached). Is changed depending on the shape and size of the object to be coated.

The hanging protrusion 109 is a portion for hooking the hanger 105 to a hanger suspension support bar which will be described later. The hanging protrusion 109 is provided to penetrate the upper end portion of the pawl 106 in a direction parallel to the hook attachment bar 107.

The tag attachment part 110 (refer FIG. 8) is a part for attaching and detaching the tag mentioned later freely, and has a short cylindrical shape, and protrudes horizontally from the slightly upper position of the hanging protrusion 109 among the poles 106. It is installed in a state.

As the hanger used by this coating apparatus 101, several types are prepared including the hanger 105 shown in drawing, The size of the pole 106 and the hook attachment bar 107 is basically the same, and the hook The number of stages of the attachment bar 107 is somewhat different. In addition, there are many kinds of workpiece hooks to some extent. The difference of the kind is the number, shape, height of the arm 108b, the size of the hook portion 108c, and the like. The shape and size of the attachment portion 108a are common.

[B. Paint booth] (Fig. 6, Fig. 11, Fig. 12)

121 denotes a paint booth. The coating booth 121 has a large cylindrical shape of polygons as seen from above, and is almost airtightly surrounded by a cylindrical outer wall, and various necessary accessories are arranged around it.

The interior of the painting booth 121 is provided with six processing sections having a substantially long hexagonal main shaft arrangement section 122 at the center thereof and a circumference of the main shaft arrangement section 122 having substantially the same size. The partition wall which forms the partition is provided with the longitudinally long hanger gate 123. The hanger gate 123 is opened and closed each time the hanger 105 enters and exits each processing unit.

The six treatment parts are the water supply part 124, the two paint application parts 125 and 125 ', the heating part 126, the heat balance part 127, and the cooling part 128, in this order. It is arranged in the clockwise direction seen from above, and the water supply part 124 is adjacent to the to-be-processed object supply part mentioned later.

The water supply part 124 is a process part which flips over the hanger 105 between the to-be-coated object supply part, and the paint application part 125 and 125 'is a powder coating material P to the to-be-coated object 103. The heating part 126 is a processing part which bakes and drys the powder coating material P by applying high frequency induction heating to the to-be-coated object 103 to which the powder coating material P was apply | coated. The thermal balance part 127 is a processing part which balances the heating performed by the heating part 126, and the cooling part 128 is a processing part which cools the heated to-be-processed object 103. FIG.

Two paint application parts 125 and 125 'are used according to the color of the paint to be used.

[B-1. Hanger feed means] (Fig. 6, Fig. 7)

A vertical main shaft 131 is freely rotatable around the shaft, and the main shaft 131 is intermittently rotated at a center angle of 60 ° by the rotating mechanism 132. . This direction of rotation is the clockwise direction seen from above.

The upper end of the main shaft 131 protrudes upward from the coating booth 121, and six horizontal hanger suspension support bars 133 protrude radially at intervals of 60 ° from the center. At the distal end of the hanger suspension support bar 133, a hanger suspending member (not shown) provided with a suspending step for holding the suspending protrusion 109 of the hanger 105 is freely rotatable around the axis of the vertical axis. have. This hanger hanging member is rotated by the rotating mechanism 134. This rotation is to reverse the direction of the hanger 105.

The stop position in the intermittent rotation of the main shaft 131 comes to the place where the hanger suspension support bar 133 corresponds to a substantially central portion of the processing units 124 to 128 as shown in FIGS. 6 and 7, respectively. Location.

The hanger 105 which hung the target object to be coated 103 hangs on the hanger hanging member of the hanger suspension support bar 133 at the water supply part 124 in the attitude to drop here. Therefore, by rotating the main shaft 131, the hanger 105 is conveyed so as to draw a circular circumferential raceway in the paint booth 121, and by this conveyance, the workpiece to be suspended from the hanger 105 ( 103 is conveyed in this order from the said coating | coated coating part 125, the coating | coated coating part 125 ', the heating part 126, the thermal balance part 127, and the cooling part 128 in this order, and the predetermined process by each process part is carried out. Is carried out.

[B-2. Paint coating part] (FIG. 6, FIG. 7, FIG. 14)

On the outside of the paint application parts 125 and 125 ', the paint (supplier142) is arrange | positioned adjacent to the spray gun traveling part 141, respectively. The spray gun traveling portion 141 is provided with a chain 143 (see FIG. 14) running in the up and down direction, a motor 144 for driving the same, and the like to spray the powder coating P onto the chain 143. Gun 145 is attached. The spray gun 145 is a bladder type in which a plurality of nozzles are arranged in a width slightly longer than the width of the hanger 105. The spray gun 145 is transferred to the hanger 105 which is conveyed in the paint coating parts 125 and 125 '. It is located in the front facing direction. The pipe connected to the spray gun 145 protrudes out of the booth through a vertically long slit formed on the circumferential wall of the painting booth 121 and is fixed to the chain 143.

The motor 144 raises and lowers the spray gun 145 in the vertical direction by switching the rotation direction at a predetermined timing. The powder coating P is supplied to the spray gun 145 from the coating reciprocating machine 142 and sprayed toward the coating object 103 according to this lifting. The paint supply system or the tip of the nozzle of the spray gun 145 is provided with a means for charging static electricity to the paint, such as a friction tube, a corona discharge plug, and the like, and sprays the powder from the spray gun 145. The paint P charges static electricity.

[B-3. Heating part] (Fig. 6, Fig. 11, Fig. 12)

The heating unit 126 is provided with two high frequency induction coils 151 and 151 '. These high frequency induction coils 151 and 151 'are processed as if they are in a substantially elliptical vortex that are vertically long in a plane. There is no. These high frequency induction coils 151, 151 'are stored in a posture perpendicular to the two coil cases 152, which are substantially the same as the entire size of the hanger 105, and form a vertically long box.

Thus, although the high frequency induction coils 151 and 151 'are mutually independent in a vortex shape, they are connected integrally in circuit by connecting each end with the steel twisted line 153. As shown in FIG. The high frequency induction coils 151 and 151 'are processed with a thin copper pipe in order to form a channel through which cooling water flows, and each channel is connected by a flexible hose 154.

A slide block 155 is attached to the bottom of the coil case 152, and the slide block 155 is freely engaged with the guide rail 156 disposed on the bottom of the heating part 126. As a result, the two high frequency induction coils 151 and 151 'are freely moved so as to face each other along the transfer path of the hanger 105 and to enlarge and reduce the space therebetween.

A nut 157 which forms a reverse screw relationship with each other is fixed to the lower ends of the two coil cases 152, and one screw shaft 158 is screwed onto these nuts 157. The screw shaft 158 is rotated by the stepping motor 159. Therefore, when this stepping motor 159 is driven, the two coil cases 152 move to opposite sides, and the space | interval between the high frequency induction coils 151 and 151 'expands and contracts.

[B-4. Thermal balance, cooling] (Fig. 6)

In the thermal balance part 127, many far-infrared heaters 161 having an output of several kilowatts are arranged.

The cooling fan 162 is arranged in the cooling unit 128.

[C. Coating object supply part] (Fig. 6)

In front of the coating booth 121, the object to be supplied 171 is provided in contact with the water supply unit 124, and the object to be coated 171 is a conveying chain 173 which horizontally runs at a high level. ). The transfer chain 173 has a plurality of hanging members for hanging the hanging projections 109 of the hanger 105 at regular intervals, and stops the position where one of the hanging members comes in front of the water supply unit 124. It runs intermittently as a position.

The hanger 105 which hangs the to-be-processed object 103 hangs on the conveyance chain 173 at the predetermined position of this to-be-processed object supply part 171. As shown in FIG. Therefore, this hanger 105 is conveyed toward the coating booth 121 by the conveying chain 173, and the said hanger suspension support bar is carried out by the transfer robot which is not shown in the position in front of the water supply part 124 ( 133). And the hanger 105 which returned to the water supply part 124 round the inside of the painting booth 121 is returned to the transfer chain 173 by a transfer robot, and is separated from the transfer chain 173 at a predetermined position.

[D. Control system] (FIG. 14)

The control system is basically configured by the SID-TAG system.

Control items related to the processing performed in the coating booth 121, in particular, the lifting frequency of the spray gun 145, the spraying amount of the powder coating, the position of the high frequency induction coils 151, 151 'and the heating time by the coil are controlled. The control system 181 for FIG. 14 is shown in FIG.

182 shows a spray gun motor drive circuit for controlling the motor 144 for spray gun travel.

183 shows the paint valve inserted in the paint supply system connected to the spray gun 145.

This paint valve 183 is equipped with the opening degree adjustment mechanism which changes an opening degree according to an electrical instruction | command, and this opening degree adjustment mechanism is controlled by the paint valve control circuit 184.

185 denotes a coil motor driving circuit for controlling the motor 159 for moving the coil case 152, and 186 denotes a position sensor such as a proximity switch. This position sensor 186 is for detecting the standby position which is the moving origin of the coil case 152, and outputs a signal at the point where the coil case 152 comes to the standby position shown by the dashed-dotted line shown in FIG.

187 shows a coil drive circuit for controlling energization to the high frequency induction coils 151 and 151 ', and includes a timer 187a for controlling the energization time.

188 denotes a tag and 189 denotes a data reading circuit. In the tag 188, the article number data of the object to be coated is written by writing means (not shown). The tag 188 is detachably attached to the tag mounting portion 110 provided on the hanger 105.

The data recorded in the tag 188 is transmitted from the antenna included in the tag 188 to the antenna of the data reading circuit 189 and read by the data reading circuit 189.

190 denotes a processing unit. This processing unit 190 does not refer to the processing unit in consultation, and defines the number of times to raise and lower the spray gun 145, the opening degree of the paint valve 183, the painting, and the distance between the coil and the coated object. Control data files such as the amount of rotation of the stepping motor 159 and the energization time to the high frequency induction coils 151 and 151 'correspond to the control data file written for each part number of the workpiece and the part number read by the data reading circuit 189. And a storage unit such as a program file in which a procedure for reading control data from the control data file and outputting predetermined control signals to the control circuits 182, 184, 185, and 187 is written.

A part of the contents of the control data file is shown in Table 1.

The powder coating apparatus 101 is comprised as mentioned above.

[E. How to use and function]

Next, the use method and operation | movement of this powder coating apparatus 101 are demonstrated.

E-1. Preprocessing]

Prior to starting painting, the SID-TAG stem writes the optimal control data and necessary painting data for each coated object empirically obtained in association with the article number of the coated object in the control data file.

In hanging the to-be-coated object to the hanger 105, while selecting the to-be-worked hook 108 of the kind suitable for the said to-be-applied object, the number to attach to the hook attachment bar 107 is selected. In particular, the height H (see FIG. 10) of the arm 108b is selected to be longer than the dimension L from the hook hole 103a to the upper end of the object to be coated 103. In addition, when the object to be supported is supported at one place, the object to be coated with the shape described above is used, and when it is to be supported at two places, the object to be covered with two arms 108b is used. When the size of a to-be-coated object is large, it attaches two to one hook attachment bar 107, and when it is small, it attaches three.

As a rule of thumb, when the heating rate of the workpiece is different due to the difference in position with respect to the high frequency induction coils 151 and 151 ', even if the same workpiece is different, the high frequency induction effect is different in the place where the speed is slow. In order to make it higher than that, the arm 108b uses an elongated workpiece hook.

In this manner, the type and number of the workpiece to be hooked are selected and attached to the hook attachment bar 107, and then the object to be coated is suspended on the workpiece hook. As shown in FIG. 9, this is performed by slightly inserting the hook portion 108c of the workpiece hook 108 into the hook hole 103a of the object to be coated 103. Only one coated object of the same type is suspended to one hanger 105.

And the article number of the to-be-hung object which hanged on the hanger 105 is written in SID-TAG 188, and it inserts into the tag mounting part 110 of the hanger 105. FIG.

The hanger 105 in this state is fastened to the transfer chain 173.

E-2. stamp]

When the hanger 105 to which the workpiece 103 is suspended is conveyed to a predetermined position close to the water supply unit 124, the data reading circuit 189 receives the data of the tag 188. The processing unit 190 reads out the control data or the painting data corresponding to the part number data received by the data reading circuit 189 from the control data file, converts it into a predetermined control signal, and outputs it to the corresponding control circuit. This output is sequentially performed at a timing synchronized with a signal for controlling rotation of the main shaft 131.

Subsequently, the hanger 105 is carried on the hanger suspension support bar 133 and moved. The attitude | position of the hanger 105 at this time is performed in the attitude | position parallel to the straight line which the hook attachment bar 107 circumscribes to the rotation trace of the hanger suspension support bar 133, as shown in FIG.

In this way, the hanger 105 conveyed in the coating booth 121 is first transferred to the paint coating unit 125 and stopped at a position facing the spray gun 145. When the coating of the to-be-coated object coincides with the painting in the paint coating unit 125, paint coating is performed here. Otherwise, paint coating is performed at the point transferred to the next paint coating unit 125 '. This paint application is controlled as follows.

The control signal is output from the processing unit 190 to the spray gun traveling section 141 or the paint recipe machine 142, whereby the spray gun 145 moves up and down the required number of times, thereby the powder coating material toward the hanger 105. (P) The powder coating material P becomes an amount suitable for the opening degree of the paint valve 183 controlled according to the control signal, and is attached to one side of the hanger 105 and the object to be coated 103 by charged static electricity. do.

If double-sided painting is required, the direction of the hanger 105 is reversed at the point where the spray gun 145 completes the lifting of the predetermined number of times, and the coating of the paint on the other side is started. In this case, since the whole of the object to be coated 103 is located at a lower position than the hooking bar 107, the hooking bar 107 casts a shadow on the paint sprayed from the rear side on the workpiece 103. Since the arm 108b of the workpiece hook 108 is a wire rod, the arm 108b does not interfere with the spraying of the paint.

[E-3. Heating etc.]

In this way, the hanger 105 to which powder coating material P was apply | coated in paint application part 125 and 125 'is then conveyed to the heating part 126. FIG. Prior to this, the two coil cases 152 are in the standby position described above and occupy a wide distance between them. Therefore, the hanger 105 smoothly enters between the two coil cases 152.

When the hanger 105 comes to this position, a control signal is output from the processing unit 190 to the coil motor drive circuit 185, whereby the stepping motor 159 rotates by a predetermined amount so that the two coil cases ( While advancing 152 to the hanger 105 to a predetermined position, a drive signal is output to the coil drive circuit 189 and energized by the high frequency induction coils 151 and 151 '.

By the induction heating using these coils 151 and 151 ', the to-be-coated object 103 itself is heated, and by this heating, the powder coating material P which adhered to the surface is baked and dried. Since the whole hanger 5 is formed by phosphor bronze, it is not inductively heated. Therefore, the powder coating material P attached to each part of the hanger 105 is not baked.

When the prescribed heating time elapses, energization to the high frequency induction coils 151 and 151 'stops and the coils 151 and 151' return to the standby position.

Next, the hanger 105 is transferred to the heat balance unit 127 to achieve thermal balance, cooled by the cooling unit 128, returned to the water supply unit 124, and loaded on the transfer chain 173.

In addition, the powder coating material P attached to the hanger 105 is shaken off by the blower which is not shown in the heat balance part 127, and is collect | recovered by the baumum.

According to this embodiment, the exchange of the workpiece hook 108 and the change of position can be made extremely simple, or the workpiece hook 108 prevents the coating of the coating object 103 from being sprayed. Less work

Moreover, according to this embodiment, the heating by the high frequency induction coil 151 acts uniformly by all the to-be-processed object 103 which hanged on the hanger 105, or this coil 151 and the to-be-processed object The opposing distance with (103) can be adjusted.

Moreover, according to this embodiment, the control items which influence the quality of painting, such as coating of paint and baking drying, can be automatically controlled by the content set previously in a hanger unit, and operation efficiency is good.

As mentioned above, although 2nd Embodiment was described, this invention is not limited to this embodiment, Even if there exists a design change etc. in the range which does not deviate from the summary of this invention, it is contained in this invention.

For example, in the second embodiment, the SID-TAG system is used, but is not limited to such a system.

According to the present invention, a uniform and firm coating film without spots can be formed, and further, the apparatus can be miniaturized and the efficiency of the painting work can be further improved.

Claims (10)

A high frequency induction heating powder coating comprising: a paint coating portion for applying powder coating on the surface of a coating object, and a heating portion for baking and drying the powder coating by applying high frequency induction heating to a coated object to which the powder coating is applied. Device. The powder coating device according to claim 1, wherein the coating device is provided with a hanger for holding the object to be coated in a suspended state, and the hanger is made of a material which is not heated by high frequency. The powder coating device according to claim 1, wherein a conveying device having a rotary conveying path for rotating the object to be coated on a horizontal circle track is provided. A high frequency induction heating step of baking and drying the powder coating from the inside by applying a high frequency induction heating of the coated object to which the powder coating is applied. Heating powder coating method. The plurality of treatment portions according to claim 1, further comprising: a coating portion for applying the powder coating to the coated object, and a plurality of processing portions including a heating portion for baking and drying the powder coating by applying high frequency induction heating to the coated object coated with the powder coating; A high frequency induction heating powder coating device comprising a hanger having a workpiece hook attached to a horizontal hook attachment bar and a hanger transfer means for sequentially transferring the hanger to the plurality of processing units, wherein the workpiece hook has a substantially inverted U shape. And an arm extending from one end of the attachment portion, wherein the hook attachment bar has a plurality of vertical grooves formed in the transverse direction for freely engaging the attachment portion. Powder coating equipment. 6. The method of claim 5, wherein the attaching portion and the arm of the workpiece hook are formed by a wire having a circular cross section, and the distal end portion of the arm extends to a position lower than the attaching portion. Powder coating apparatus characterized by attaching an arrowhead hook portion for hanging. 2. The plurality of processing portions according to claim 1, comprising: a coating portion for applying the powder coating to the coated object, and a plurality of processing portions including a heating portion for baking and drying the powder coating by induction heating the coated object coated with the powder coating; A hanger with a workpiece hook attached to a horizontal hook attachment bar, and a hanger transfer means for sequentially transferring the hanger to the plurality of processing units, wherein the high-frequency induction coil of the heating unit is opposed to each other along the transfer path of the hanger. Powder coating device, characterized in that arranged two. 8. A coil position control means for supporting two high frequency induction coils on a coil support base which is free to move on the opposite side in the opposite direction thereof, and moving the coil support base. Powder coating device characterized in that. 9. The tag according to claim 8, further comprising: a tag attached to a hanger and writing position control data or surrogate data of two high frequency induction coils, a data reading circuit for reading the data recorded on the tag, and a data reading circuit read out by the data reading circuit. And a processing unit for generating a control signal based on the data, and a control circuit for controlling the position of the coil based on the control signal. 2. The plurality of processing portions according to claim 1, further comprising: a paint coating portion for applying the powder coating to the coated object, and a heating portion for baking and drying the powder coating by applying high frequency induction heating to the coated object coated with the powder coating, and A hanger having a plurality of coating hooks attached at least in the up and down direction, hanger conveying means for sequentially transferring the hangers to the plurality of processing units, a tag attached to the hanger and recording control data or proxy data, and recorded in this tag On the basis of the data reading circuit for reading data and the data read out by the data reading circuit, at least one control item among the number of movements of the spray gun, the spray amount of the powder paint from the spray gun, and the heating time by the high frequency induction coil A processing unit for generating a control signal for the control unit; and a control circuit for controlling the control item based on the control signal. Powder coating apparatus characterized in that it includes.