JP2016203042A - Thermal spray nozzle, thermal spray device and thermal spray method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal spray nozzle capable of thermally spraying accurately, efficiently and peripherally without lowering efficiency of the whole line; and to provide a thermal spray device and a thermal spray method.SOLUTION: A thermal spray nozzle 100 that thermally sprays powder on an object by jetting out the powder into heating gas, having a powder nozzle 110 for jetting out the powder, and a heating gas passage member 120 for jetting out heating gas, has a peripheral thermal spray nozzle part 121 on the tip side of the heating gas passage member 120, and is constituted so that the powder is jetted out from the powder nozzle 110 so as to join heating gas near the outlet of the peripheral thermal spray nozzle part 121.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a thermal spraying nozzle, a thermal spraying apparatus, and a thermal spraying method for spraying circumferentially on the surface of an object.

As a means for coating the surface of an object with a resin or the like, a method of discharging a molten resin with a hot melt gun is generally performed. However, applicable resins are limited, and the application range is narrow.
Further, since a stringing phenomenon of the resin occurs after discharging from the nozzle, there is a problem that it is difficult to accurately cover a narrow region, the resin is wasted, and the cycle up is difficult.
The use of a hot runner instead of a hot melt gun widens the applicable resin range, but the same stringing phenomenon occurs.
In addition, there are wet methods such as resin solution coating and emulsion coating, but there are problems that the material is limited and the solvent has to be vaporized after coating, and the environmental load of the solvent is high.

Furthermore, a method of forming a film by injecting molten resin, which is extruded and melted with a screw while heating a resin raw material in the same manner as an injection molding machine, onto a surface of an object such as metal is formed (Patent) Reference 1).
Although this device is suitable for resin coating on the surface of a large object, accurate intermittent injection of a small amount of resin is difficult. For example, a small amount of resin is placed on the stepped portion of an opening curl portion such as a paper cup. In addition, there are problems such as being difficult to apply to applications such as, making it difficult to reduce the size and speed of the apparatus, and increasing the equipment cost.

In addition, as another method, it is also known that an adhesive resin powder is coated on the surface of an object by flame spraying using a flame of acetylene, propane or the like with a spray gun (see Patent Document 2).
However, in this case as well, intermittent treatment and spray pattern control are difficult, reliable spray coating in a narrow area is difficult, and there is a possibility that the target object or the coating resin itself may be thermally deteriorated by the flame.
In order to solve these problems, the present applicant has proposed a thermal spraying (coating) apparatus and a thermal spraying (coating) method in which powder mainly composed of a synthetic resin is intermittently ejected with a heated gas (Japanese Patent Application No. 2014-2014). 112617).

JP 09-201833 A JP-A-63-141666 JP 62-186972 A Japanese Patent Laid-Open No. 06-206025 JP, 2014-19468, A

In the conventionally known technique or the technique proposed by the present applicant, when it is desired to perform thermal spraying on the surface of the object, it is necessary to rotate or move the spray nozzle or the object along the circumference.
It is known (for example, refer to Patent Documents 3 and 4) that fixes one of the spray nozzle and the object and rotates the other.
There is no problem if the object is relatively large and high-speed processing is not required as in the techniques known in Patent Documents 3 and 4, but the bottom of the inner surface of the paper cup as in the technique known in Patent Document 5 In the case of coating the periphery, etc., when applied in a production line that requires high-speed processing, there is a problem that a predetermined time is required until the processing is completed, and the efficiency of the entire manufacturing line is lowered.
In addition, in the case of a low-strength object such as a paper cup, it is difficult to accurately position and fix the object on a high-speed production line, and there is a problem that the equipment is complicated and the processing speed is reduced.

  The present invention solves the above-described problems, and provides a thermal spray nozzle, a thermal spraying apparatus, and a thermal spraying method that can perform thermal spraying accurately and efficiently in a circumferential shape without reducing the efficiency of the entire line. It is the purpose.

The thermal spray nozzle according to the present invention has a powder nozzle for ejecting powder and a heated gas flow path member for ejecting heated gas, and sprays the powder into the heated gas flow to thermally spray the object. A nozzle having a circumferential spray nozzle on the tip side of the heating gas flow path member, and the powder nozzle is joined to the heating gas in the vicinity of the outlet of the circumferential spray nozzle. The above-mentioned problem is solved by being configured to eject.
A thermal spraying apparatus according to the present invention is a thermal spraying apparatus including a plurality of the above-described thermal spray nozzles, and each of the thermal spray nozzles includes a plurality of powder ejection holes arranged circumferentially, and the powder ejection holes. The said subject is solved by arrange | positioning so that the position of the circumferential direction may differ.
Further, the thermal spraying method according to the present invention is a thermal spraying method in which the thermal spraying is performed circumferentially by the thermal spraying nozzle, and the thermal spraying nozzle has a plurality of circumferentially arranged powder ejection holes, and the powder ejection holes The above-mentioned problem is solved by performing thermal spraying a plurality of times so that the positions in the circumferential direction are different.

  According to the thermal spray nozzle according to the first aspect of the present invention, by having the circumferential thermal spray nozzle portion on the tip side of the heated gas flow path member, the thermal spray nozzle and the object are not rotated or moved along the circumference. Since thermal spraying can be performed circumferentially on the surface of the object, thermal spraying can be performed accurately and efficiently circumferentially without reducing the efficiency of the entire line even when incorporated in a production line.

According to the configuration of the second aspect of the present invention, the heating gas flow path member is configured in a cylindrical shape that interpolates the powder nozzle, and a circumferential heating gas is interposed between the heating gas flow path member and the powder nozzle. By forming the flow path, it becomes possible to spray the heated gas uniformly in a circumferential shape with a simple configuration, and more accurately and efficiently spray the circumferential shape.
According to the configuration of the third aspect of the present invention, the powder nozzle has a plurality of powder injection holes in the circumferential shape, so that the powder to be sprayed can be uniformly ejected in the circumferential direction. As a result, it is possible to perform thermal spraying more accurately and efficiently.
According to the configuration of the fourth aspect of the present invention, the circumferential spray nozzle portion includes the inner nozzle member that forms a predetermined ejection flow path between the outlet extension portion of the heated gas flow path member and the outlet extension portion. This simplifies the nozzle structure.
According to the fifth aspect of the present invention, since the inner nozzle member is detachably provided on the tip side of the powder nozzle, maintenance of the inner surface of the circumferential spray nozzle portion is facilitated, and accurate spraying is performed. Can be maintained.

According to the configuration of the sixth aspect of the present invention, since the outlet extension portion is detachably provided on the distal end side of the heated gas flow path member, the entire circumferential spray nozzle portion can be detachable. Furthermore, it becomes possible to perform maintenance more reliably.
According to the configuration of the seventh aspect of the present invention, it is possible to perform thermal spraying more accurately by providing the shutter portion for cutting out the powder by a fixed amount on the upstream side of the powder nozzle.
According to the configuration of the present invention, the circumferential heating gas flow path has the shield air flow path member that separates the heating gas flow path member and the powder nozzle from the powder nozzle, Air for heat insulation can be supplied between the shield air flow path members, and the powder nozzles can be ejected without overheating the powder nozzle due to the heat in the circumferential heated gas flow path. Is stable and more accurate thermal spraying can be performed.

According to the thermal spraying apparatus according to the ninth aspect of the present invention, the plurality of thermal spray nozzles each have a plurality of powder nozzle ejection holes arranged circumferentially, and the circumferential positions of the powder nozzle ejection holes are different. Therefore, even if spraying is performed in a small amount for a short time, it can be sprayed in a circumferential shape accurately over the entire circumference by dividing into a plurality of times.
In addition, since multiple spray nozzles are arranged, the target can be processed continuously, there is no decrease in the speed of the entire line, and the speed is reduced by reducing the spraying amount per time and shortening the spraying time. It is possible to improve the efficiency.
According to the thermal spraying method according to claim 10, by spraying a plurality of times so that the circumferential position of the ejection hole of the powder nozzle is different, even in a short amount of spraying in a small amount, it is divided into a plurality of times, It becomes possible to perform thermal spraying accurately on the entire circumference.

Sectional drawing of the thermal spray nozzle which concerns on 1st Embodiment of this invention. Sectional drawing and bottom view of the front-end | tip part of a powder nozzle. Explanatory drawing of a thermal spray nozzle concerning a 1st embodiment of the present invention. Explanatory drawing of the arrangement | sequence of the ejection hole of a powder nozzle. Explanatory drawing of other embodiment of a powder nozzle. Explanatory drawing of the thermal spray nozzle and the cleaning means which concern on 2nd Embodiment of this invention. Explanatory drawing at the time of the cleaning of the thermal spray nozzle which concerns on 2nd Embodiment of this invention. Explanatory drawing of the thermal spray nozzle and the cleaning means which concern on 3rd Embodiment of this invention. Explanatory drawing at the time of cleaning of the thermal spray nozzle which concerns on 3rd Embodiment of this invention. Explanatory drawing of the cleaning means of the other form of the thermal spray nozzle which concerns on 3rd Embodiment of this invention. Explanatory drawing of the thermal spray nozzle and the cleaning means which concern on 4th Embodiment of this invention.

As shown in FIG. 1, the thermal spray nozzle 100 according to the first embodiment of the present invention includes a powder nozzle 110 that ejects powder and a heated gas passage member 120 that ejects heated gas, and is made of a synthetic resin. Or the like is sprayed into the heated gas and sprayed onto the surface of the object.
On the front end side of the heated gas flow path member 120, there is a circumferential spray nozzle portion 121 composed of the outlet extension 122 of the heated gas flow path member 120 and the inner nozzle member 123, and the front end of the powder nozzle 110. The powder ejected from the ejection holes 111 is configured to merge with the heating gas in the vicinity of the outlet of the circumferential spray nozzle portion 121.

The heating gas channel member 120 is formed in a cylindrical shape for inserting the powder nozzle 110, and a circumferential heating gas channel is formed between the heating gas channel member 120 and the powder nozzle 110 to supply the heating gas. The heated gas is supplied from the pipe 124, and the heated gas is ejected from the circumferential spray nozzle portion 121.
In the present embodiment, a cylindrical shield air flow path member 130 that separates the heating gas flow path member 120 and the powder nozzle 110 is provided in the circumferential heating gas flow path so that the heating gas is shielded. It is configured to flow outside the air flow path member 130.

As shown in FIG. 2, the powder nozzle 110 has eight powder ejection holes 111 at regular intervals in a circumferential shape.
On the upstream side of the powder nozzle 110, there is a shutter portion (not shown) that cuts out the powder by a fixed amount, and a desired amount of powder can be ejected from the ejection hole 111 at a desired timing. Yes.
In addition, although the number of the ejection holes 111 was eight at equal intervals, what is necessary is just to set the space | interval and the number suitably according to the spraying quantity with respect to a thermal spraying object, and a spraying aspect.
Also, the opening shape is circular in the drawing, but it may be long in the circumferential direction or may be formed in a slit shape continuous in the circumferential direction.

The operation of spraying and coating the resin on the inner surface bottom edge of the container C with the spray nozzle 100 of the first embodiment configured as described above will be described with reference to FIG.
The thermal spray nozzle 100 and the container C to be sprayed move relative to each other, and the thermal spray nozzle 100 is inserted into the container C up to a position at which the inner surface bottom edge of the container C can be sprayed.
During this insertion movement, only the heating gas HG is ejected, and when reaching the spraying position, a predetermined amount of resin powder PW is ejected from the ejection hole 111 of the powder nozzle 110 as shown in FIG.

The ejected powder PW merges with the heating gas HG near the outlet of the circumferential spray nozzle 121, becomes a molten or semi-molten state by the heat of the heating gas HG, adheres to the inner periphery of the bottom of the inner surface of the container C, and A resin coating is obtained.
The heated gas HG thereafter becomes exhaust EG and is discharged from above the container C.
In the present embodiment, the cooling gas CG is supplied between the powder nozzle 110 and the shield air flow path member 130 so that the powder nozzle 110 is not affected by the heat of the heating gas HG. The supply amount may be a small amount that can exert a heat insulation effect, and does not affect the temperature and flow of the heated gas HG.

In the thermal spraying from the ejection holes 111, the amount of thermal spraying decreases as the ejection direction is away from the center line. Therefore, in the thermal spraying from the ejection holes 111 arranged at equal intervals in the circumferential shape, the entire circumference of the inner peripheral bottom portion of the container C is uniform. May not be coated.
The entire circumference of the inner bottom bottom edge of the container C is long, and it may be necessary to increase the amount of spraying once.
In such a case, for example, by spraying twice at the position of the ejection hole 111a shown in FIG. 4a and the position of the ejection hole 111b shown in FIG. It becomes possible to reduce the amount of thermal spraying and perform more uniform coating.
In order to perform the thermal spraying twice, the entire thermal spray nozzle 100 may be rotated, and the thermal spray nozzle having the powder nozzle 110a shown in FIG. 4a and the powder nozzle 110b in FIG. A thermal spray nozzle may be prepared and sprayed in two steps.
Further, the pitch shifted in the circumferential direction may be set to 1 / n (n ≧ 2: n is an integer) and sprayed n times.

Further, in the case of an elliptic container, for example, in the case of an elliptical container, the inner periphery of the inner bottom portion has an elliptical shape as shown in FIG. 5, and the other configurations are all configured in accordance with this shape. It is possible to cope with.
In the case of such a shape, since the method of rotating the entire spray nozzle cannot be employed, when spraying n times, a method of preparing n spray nozzles having different positions of the ejection holes 111 is employed.

In the thermal spray nozzle according to the second embodiment of the present invention, as shown in FIG. 6, the inner nozzle member 123 is movable in the vertical direction shown in the figure to the mounting portion 112 provided at the center of the tip of the powder nozzle 110. Other configurations are the same as those of the first embodiment (the illustration is also simplified).
And either of the container holding member T holding the container to be sprayed and the dust collecting member 141 is configured to be relatively movable so as to come below the spray nozzle.

The operation | movement at the time of the cleaning of the thermal spray nozzle of 2nd Embodiment comprised as mentioned above is demonstrated.
First, as shown in FIG. 6, in a state where the container holding member T is positioned below the thermal spray nozzle, after performing the same thermal spraying operation as the thermal spray nozzle of the first embodiment, dust collection is performed below the thermal spray nozzle. Relative movement is performed so that the member 141 is positioned.
Then, as shown in FIG. 7, the inner nozzle member 123 is pressed against the dust collecting member 141, and the inner nozzle member 123 is moved toward the powder nozzle 110 to reduce the outlet interval of the spray nozzle.
In this state, the cleaning gas SG is ejected through the same path as the heating gas HG at the time of thermal spraying, thereby increasing the flow rate of the cleaning gas SG at the outlet of the thermal spray nozzle and removing the powder adhering to the inner surface.
The removed powder is collected by the dust collecting member 141 and is not scattered around.
The cleaning gas SG may be supplied by providing an introduction valve or the like on the heating gas supply path at the time of thermal spraying, and the heating gas for thermal spraying is used as it is or after the heating is stopped as the cleaning gas SG. May be used.

As shown in FIG. 8, the thermal spray nozzle according to the third embodiment of the present invention is an outlet in which the outlet extension portion 122 is formed so as to be connectable and separable from the heated gas flow path member 120 and constitutes the circumferential thermal spray nozzle portion 121. The extension 122 and the inner nozzle member 123 are integrated independently, and the other configurations are the same as those in the first embodiment (the illustration is also simplified).
The cleaning nozzle 142 is disposed on the side of the spray nozzle, and the circumferential spray nozzle portion 121 is configured to be movable below the cleaning nozzle 142 by the slide separation chuck 144.

The operation | movement at the time of the cleaning of the thermal spray nozzle of 3rd Embodiment comprised as mentioned above is demonstrated.
First, as shown in FIG. 8, in the state where the container holding member T is positioned below the thermal spray nozzle, after performing the thermal spraying operation similar to the thermal spray nozzle of the first embodiment, the slide separation chuck 144 has a circumferential shape. The thermal spray nozzle 121 is moved.
Then, as shown in FIG. 9, the circumferential spray nozzle 121 is positioned below the cleaning nozzle 142, and the cleaning nozzle 142 is lowered and inserted into the circumferential spray nozzle 121.
In this state, the cleaning gas is ejected from the cleaning nozzle 142 to remove the powder adhering to the inner surface.
When the circumferential spray nozzle 121 is circular, instead of the cleaning nozzle 142, as shown in FIG. 10, the integrated cleaning brush 143 is disposed on the side of the spray nozzle, and the integrated cleaning brush 143 is inserted. By rotating, the powder adhering to the inner surface may be removed.

In the thermal spray nozzle according to the fourth embodiment of the present invention, as shown in FIG. 11, the inner nozzle member 123 is detachably attached to an attachment portion 112 provided at the center of the tip of the powder nozzle 110. The other configuration is the same as that of the first embodiment (the illustration is also simplified).
And either the container holding member which hold | maintains the container which should be sprayed, and the up-and-down separation chuck | zipper 146 are comprised so that relative movement is possible so that it may come under the thermal spray nozzle.
In addition, a separation-type cleaning brush 145 is disposed in the vicinity of the upper and lower separation chuck 146.

The operation | movement at the time of the cleaning of the thermal spray nozzle of 4th Embodiment comprised as mentioned above is demonstrated.
First, in a state in which the container holding member is positioned below the thermal spray nozzle, after performing the same thermal spraying operation as the thermal spray nozzle of the first embodiment, the upper and lower separation chucks 146 are relatively positioned below the thermal spray nozzle. Moving.
Then, as shown in FIG. 11, the inner nozzle member 123 is separated and fixed downward by the upper and lower separation chucks 146, and the outlet extension 122 of the heated gas flow path member 120 and the inner nozzle member 123 are separated by the separation-type cleaning brush 145. The powder adhering to the portion corresponding to the inner surface of the circumferential spray nozzle portion is removed.

DESCRIPTION OF SYMBOLS 100 ... Spray nozzle 110 ... Powder nozzle 111 ... Injection hole 112 ... Mounting part 120 ... Heating gas flow path member 121 ... Circumferential spray nozzle part 122 ... Outlet extension part 123 ... Inner nozzle member 124 ... Heated gas supply pipe 130 ... Shield air flow path member 141 ... Dust collecting member 142 ... Cleaning nozzle 143 ... Integrated cleaning brush 144 ... Slide Separation chuck 145 ... Separation type cleaning brush 146 ... Upper and lower separation chuck R ... Heating gas flow path C ... Container T ... Container holding member PW ... Powder HG ... Heating gas CG・ ・ ・ Cooling gas EG ・ ・ ・ Exhaust SG ・ ・ ・ Cleaning gas

Claims (10)

A thermal spray nozzle that has a powder nozzle that ejects powder and a heated gas flow path member that ejects heated gas, and sprays the powder into the heated gas flow to spray the object,
On the tip side of the heated gas flow path member, it has a circumferential spray nozzle part,
The thermal spray nozzle, wherein the powder nozzle is configured to eject powder so as to merge with the heated gas in the vicinity of the outlet of the circumferential thermal spray nozzle portion. The heated gas flow path member is configured in a cylindrical shape to insert the powder nozzle,
The thermal spray nozzle according to claim 1, wherein a circumferential heating gas passage is formed between the heating gas passage member and the powder nozzle.   The thermal spray nozzle according to claim 1, wherein the powder nozzle has a plurality of powder ejection holes in a circumferential shape.   The said circumferential spray nozzle part has an inner side nozzle member which forms a predetermined ejection flow path between the exit extension part of the said heating gas flow path member, and the said exit extension part. The thermal spray nozzle according to claim 3.   The thermal spray nozzle according to claim 4, wherein the inner nozzle member is detachably provided on a tip side of the powder nozzle.   The thermal spray nozzle according to claim 4 or 5, wherein the outlet extension portion is detachably provided on a distal end side of the heated gas flow path member.   The thermal spray nozzle according to any one of claims 1 to 6, further comprising a shutter portion that cuts out the powder by a predetermined amount upstream of the powder nozzle.   8. The circumferential heated gas flow path has a shield air flow path member that separates the heated gas flow path member and the powder nozzle from each other. The thermal spray nozzle described in 1. A thermal spraying apparatus comprising a plurality of thermal spray nozzles according to any one of claims 1 to 8,
Each of the plurality of thermal spray nozzles is arranged such that a plurality of ejection holes of the powder nozzle are arranged in a circumferential shape and the positions of the ejection holes of the powder nozzle are different in the circumferential direction. Thermal spray equipment. A thermal spraying method in which thermal spraying is performed circumferentially by the thermal spray nozzle according to any one of claims 1 to 8,
Each of the spray nozzles has a plurality of powder nozzle ejection holes arranged circumferentially,
The thermal spraying method is characterized in that thermal spraying is performed a plurality of times so that the circumferential positions of the ejection holes of the powder nozzle are different.

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