JP6565293B2 - Thermal spraying apparatus and thermal spraying method - Google Patents

Description

  The present invention relates to a thermal spraying apparatus and a thermal spraying method for spraying powder onto 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 05-179417 A

In the conventionally known technique or the technique proposed by the present applicant, when synthetic resin or the like adheres to and accumulates on the inner surface of the tip nozzle that is the spray outlet part of the thermal spraying device, mixing of aggregates caused by them occurs, In order to change the spraying amount, it is essential to clean the inner surface of the tip nozzle at predetermined intervals.
When cleaning the inner surface of the tip nozzle, it is necessary to temporarily stop the spraying process. For example, as in Patent Document 3, a spray mechanism is provided in advance, and the inner surface of the tip nozzle is provided at predetermined intervals. Although it is possible to reduce the time to stop compared to the case where the operator directly works, it is necessary to stop the spraying process for a predetermined time, and the object production line In the case of being incorporated in the system, there is a problem that the efficiency of the entire line is lowered.

  The present invention solves the above-described problems, and an object of the present invention is to provide a thermal spraying apparatus and a thermal spraying method that can perform thermal spraying accurately and efficiently without reducing the efficiency of the entire line. .

The thermal spraying apparatus according to the present invention is a thermal spraying apparatus that has a thermal spraying main body part and a tip nozzle, and sprays powder intermittently, and the tip nozzle is configured to be separable from the thermal spraying body part, It has a nozzle moving mechanism for moving the tip nozzle to spray position and the standby position, the upstream side of the powder flow path of the spraying body portion, by Rukoto includes a shutter portion for cutting the powder by quantitative, solving the problems To do.
Furthermore, thermal spray method according to the present invention, organic a spraying method of spraying a powder by thermal spraying device, the spraying device comprises a spraying body portion, the spraying body portion and separably configured tip Nozzle The tip nozzle is moved between a spray position and a standby position, the tip nozzle is sprayed at the spray position, and the spraying device has a cleaning mechanism for cleaning the tip nozzle, and the standby position The above-mentioned problem is solved by cleaning the tip nozzle by the cleaning mechanism.

  According to the thermal spraying apparatus according to the first aspect of the present invention, the tip nozzle is configured to be separable from the thermal spray main body portion, and has a nozzle moving mechanism that moves the tip nozzle to the spraying position and the standby position. When it is incorporated in the nozzle, the tip nozzle can be moved between the spraying position and the standby position by the nozzle moving mechanism in parallel with the movement of the object for replacement, maintenance, etc., and the efficiency of the entire line is lowered. Therefore, thermal spraying can be performed accurately and efficiently.

Furthermore , spraying can be performed more accurately by providing a shutter unit for quantitatively cutting the powder upstream of the powder flow path of the thermal spray main body.
According to the configuration of the second aspect of the present invention, the cleaning mechanism that cleans the tip nozzle located at the standby position eliminates the need for replacement of the tip nozzle and the cleaning work by the operator. The tip nozzle moved from the spraying position to the standby position can be cleaned at the standby position and used again for spraying, and the efficiency of the entire line can be further improved.
According to the configuration described in claim 3, the cleaning mechanism, by having a jet nozzle for jetting inserted and fluid tip nozzle, less moving parts, it is possible to place a small space.
In addition, it is possible to cool the tip nozzle simultaneously with cleaning by ejecting the fluid, and it is possible to reduce adhesion of resin or the like to the inner surface of the tip nozzle during thermal spraying using a heated gas.
Furthermore, cleaning can be performed at high speed by ejecting the fluid, and the efficiency of the entire line can be further improved.

According to the configuration of the present invention , the ejection nozzle has one or more ejection holes for ejecting the fluid, and the ejection hole is sprayed when the fluid is ejected toward the inner surface of the tip nozzle. By being set so as to be directed in the direction opposite to the direction, the fluid at the time of cleaning, the adhered resin, and the like are not scattered to the thermal spray target side.
According to the configuration of the fifth aspect of the present invention , the cleaning mechanism includes the brush unit that cleans the inner surface of the tip nozzle, so that it is possible to remove strongly adhered resin and the like, and By using together, the inner surface of the tip nozzle can be more reliably cleaned.
According to the configuration of the sixth aspect of the present invention , the cleaning mechanism abuts on the outlet side of the tip nozzle and has the tip ejection unit that ejects fluid toward the inside of the tip nozzle. It is possible to reliably clean up to the end, and it is possible to more reliably prevent the fluid at the time of cleaning, the adhered resin, and the like from being scattered to the thermal spray target side.
According to the configuration of the present invention, the plurality of tip nozzles including the dummy nozzles that are not used for spraying are provided, so that the temperature rise standby time required for thermal spraying using the heated gas can be achieved. By positioning the dummy nozzle at the spray position, the temperature rise of the spray nozzle is suppressed, and it becomes possible to reduce adhesion of resin or the like to the inner surface of the tip nozzle during spraying.
According to the configuration of the eighth aspect of the present invention, the tip nozzle end face and the thermal spraying main body portion move in a state of being aligned, thereby minimizing the gas temperature drop in the thermal spraying main body portion during the thermal spraying using the heated gas. It is possible to eliminate the time loss during the temperature rise standby, and the efficiency of the entire line can be further improved. Moreover, the possibility that fine particles scattered in the line are mixed is reduced, and the defect rate can be suppressed.

According to the thermal spraying method of the present invention, the tip nozzle is moved between the spraying position and the standby position, and when the tip nozzle is sprayed at the spraying position, the tip nozzle is replaced when incorporated in the production line of the object. For maintenance, etc., it is possible to move the tip nozzle between the spraying position and the standby position in parallel with the movement of the object, and spraying accurately and efficiently without reducing the efficiency of the entire line Can do.
In addition, by cleaning the tip nozzle with the cleaning mechanism at the standby position, it is not necessary to replace the tip nozzle or perform a cleaning operation by the operator, and the tip nozzle that has been moved from the spraying position to the standby position by the nozzle moving mechanism is put on standby. It can be cleaned in position and used again for thermal spraying, further improving the efficiency of the entire line.
According to the configuration described in claim 10, the spraying by the tip nozzle at spraying position, by concurrently performing cleaning other tip nozzle in the standby position, it is possible to eliminate the time loss of the cleaning, the whole line The efficiency can be further improved.

Explanatory drawing of the thermal spraying apparatus which concerns on 1st Embodiment of this invention. Explanatory drawing of the tip nozzle of a thermal spraying apparatus. Explanatory drawing of the ejection nozzle of the cleaning mechanism of a thermal spraying apparatus. Operation | movement explanatory drawing of the thermal spraying apparatus which concerns on 1st Embodiment of this invention. Explanatory drawing of the thermal spraying apparatus which concerns on 2nd Embodiment of this invention, and its operation | movement. Explanatory drawing of the thermal spraying apparatus which concerns on 3rd Embodiment of this invention, and its operation | movement. Explanatory drawing of other embodiment of the cleaning nozzle.

As shown in FIG. 1, the thermal spraying apparatus 100 according to the first embodiment of the present invention includes a thermal spraying main body 110 and a tip nozzle 120, and sprays a powder of synthetic resin or the like into a heated gas. It sprays on the surface.
The tip nozzle 120 is configured to be separable from the thermal spray main body 110 and includes a nozzle moving mechanism 130 that moves the tip nozzle 120 to the spray position Y and the standby position W.
In the present embodiment, the dummy nozzle 150 is provided, and the dummy nozzle 150 is configured to be movable to the spray position Y when the tip nozzle 120 is moved to the standby position W by the nozzle moving mechanism 130.

The nozzle moving mechanism 130 includes a plate-like nozzle support member 132 that supports the tip nozzle 120 and the dummy nozzle 150, and a reciprocating member 131 that slides the nozzle support member 132 in a direction orthogonal to the spraying direction. The tip nozzle 120 is configured to move between the spraying position Y and the standby position W by driving the member 131.
The thermal spray main body 110 includes a heated gas ejection part 111 that ejects a heated gas toward the surface of the object, and a powder ejection part 112 that ejects powder into the heated gas flow.
A predetermined amount of powder is intermittently supplied from the shutter unit 113 to the powder ejection unit 112, and the powder is ejected into the heated gas flow continuously ejected from the heated gas ejection unit 111. Then, thermal spraying according to the object is performed.
At a position corresponding to the tip nozzle 120 that has moved to the standby position W, a cleaning mechanism 140 having an ejection nozzle 141 that is inserted into the tip nozzle 120 and ejects fluid is disposed.

As shown in FIG. 2, the tip nozzle 120 has a circular cross section at the entrance on the thermal spraying main body 110 side, and the tip opening 122 is formed in an oval shape.
In addition, what is necessary is just to design the shape of the front-end | tip opening 122 suitably according to the shape of the target object surface to be sprayed.
Also, the cross-sectional shape of the inner surface 121 may be a circular cross-section that gradually decreases in diameter so that it can be smoothly sprayed to the tip opening 122, and the cross-sectional shape may be continuously changed by a predetermined length on the tip side, Only the entrance on the thermal spraying main body 110 side may have a circular cross section, and the cross-sectional shape may be continuously changed from the entrance side to the tip opening 122.

As shown in FIG. 3, the ejection nozzle 141 has an outer shape similar to the inner surface 121 of the tip nozzle 120, and has a plurality of ejection holes 142 for ejecting fluid on the outer surface, and is inserted into the tip nozzle 120. At this time, the cleaning fluid flows at a high speed through a slight gap between the inner surface 121 of the tip nozzle 120 and the inner surface of the tip nozzle 120 is cleaned and cooled.
The ejection hole 142 is set so as to be directed in the direction opposite to the spraying direction along the inner surface 121 of the tip nozzle 120 when the fluid is ejected toward the inner surface 121 of the tip nozzle 120. This prevents the fluid or the attached resin from scattering to the thermal spray target side.
In the present embodiment, eight ejection holes 142 are provided in total in four circumferential directions at two locations in the front-rear direction, but the number, arrangement, opening size, etc. are suitable for cleaning and cooling. What is necessary is just to set suitably.

The operation of the thermal spraying apparatus 100 according to the first embodiment configured as described above will be described with reference to FIG.
First, as shown in FIG. 4a, in the state where the dummy nozzle 150 is disposed at the spraying position Y, only the heating gas is continuously ejected to stabilize the temperature of the heating gas.
Next, as shown in FIG. 4b, the nozzle moving mechanism 130 is operated, the tip nozzle 120 is positioned at the spraying position Y, and an appropriate amount of powder is ejected to perform spraying.
At this time, since the heated gas continues to be ejected and the temperature of the heated gas is in a stable state, spraying is possible immediately after the tip nozzle 120 moves to the spray position Y.
Next, as shown in FIG. 4 c, the nozzle moving mechanism 130 is operated to position the tip nozzle 120 at the standby position W.
At this time, since the dummy nozzle 150 is located at the spraying position Y, only the heating gas can be continuously ejected.
Next, as shown in FIG. 4 d, the ejection nozzle 141 of the cleaning mechanism 140 is inserted into the tip nozzle 120 located at the standby position W, and the fluid is ejected from the ejection nozzle 141 to clean the inner surface of the tip nozzle 120. The tip nozzle 120 is cooled by the fluid.
Then, the ejection nozzle 141 of the cleaning mechanism 140 is retracted to return to the state of FIG. 4a, and the cycle of a → b → c → d → a is repeated.

Since the tip nozzle 120 increases the adhesion of resin or the like as the temperature rises, in the above-described cycle, the state of FIG. If the tip nozzle 120 can sufficiently cool at the time of cleaning in the state shown in FIG. 4d, the state shown in FIG. 4b may be subjected to intermittent injection of the powder a plurality of times and then shifted to the next state shown in FIG. 4c. .
In addition, the dummy nozzle 150 is cylindrical, but may have any shape as long as the heating gas can be continuously ejected to stabilize the temperature. An opening serving as a flow path for the heated gas ejected to the nozzle support member 132 may be provided, and an independent dummy nozzle may be omitted.

As shown in FIG. 5, the thermal spraying apparatus according to the second embodiment of the present invention is provided with two standby positions Wa and Wb on both sides of the thermal spray position Y, and two jets corresponding to both standby positions Wa and Wb. Nozzles 141a and 141b are provided, and two tip nozzles are provided: a tip nozzle 120a that moves between the spray position Y and the standby position Wa, and a tip nozzle 120b that moves between the spray position Y and the standby position Wb. is there.
Other configurations are the same as those in the first embodiment (the illustration is also simplified).

The operation of the thermal spraying apparatus according to the second embodiment configured as described above will be described with reference to FIG.
First, as shown in FIG. 5a, in the state where the dummy nozzle 150 is disposed at the spray position Y, only the heating gas is continuously ejected to stabilize the temperature of the heating gas.
Next, as shown in FIG. 5b, the nozzle moving mechanism 130 is operated, the tip nozzle 120b is positioned at the spraying position Y, and an appropriate amount of powder is ejected to perform spraying.
Next, as shown in FIG. 5c, the nozzle moving mechanism 130 is operated so that the tip nozzle 120a is positioned at the spraying position Y, and at the same time, the tip nozzle 120b is positioned at the standby position Wb.
At this time, spraying by the tip nozzle 120a at the spraying position Y and cleaning / cooling of the tip nozzle 120b by the ejection nozzle 141b at the standby position Wb are performed in parallel.
Next, as shown in FIG. 5b, the nozzle moving mechanism 130 is operated again, the nozzle moving mechanism 130 is operated, the tip nozzle 120b is positioned at the spraying position Y, and the tip nozzle 120a is simultaneously set at the standby position Wa. The thermal spraying by the tip nozzle 120b at the spraying position Y and the cleaning / cooling of the tip nozzle 120a by the ejection nozzle 141a at the standby position Wa are performed in parallel.
Thereafter, the cycle of b → c → b → c... Is repeated.

By this, since it becomes possible to thermally spray the object to be sprayed at all times except during the period in which the nozzle moving mechanism 130 is operating, the entire movement of the object and the timing of the nozzle moving mechanism 130 can be matched. There is no time loss and the efficiency of the entire line is not reduced.
The movement of the two nozzles 120a and 120b may be performed every time the powder is intermittently injected or after several times of injection, as in the first embodiment.
Also, the dummy nozzle 150 may have any shape as in the first embodiment, and one of the two tip nozzles 120a and 120b is sprayed without providing the dummy nozzle 150. At the position Y, only the heating gas is continuously ejected to stabilize the temperature of the heating gas, and the nozzle moving mechanism 130 is operated before the powder for spraying is ejected to switch the tip nozzle 120. Also good.

As shown in FIG. 6, the thermal spraying apparatus according to the third embodiment of the present invention includes a tip ejection unit 144 in which the cleaning mechanism abuts from the outlet side of the tip nozzle 120 and ejects fluid toward the inside of the tip nozzle 120. It is what you have.
Other configurations are the same as those in the first embodiment (the illustration is also simplified).
When the cross-sectional shape of the tip opening 122 is small, the tip of the jet nozzle 141 to be inserted also becomes thin and it is difficult to provide a jet hole toward the inner surface 121 of the tip nozzle 120 near the tip. There were cases where the neighborhood could not be cleaned and cooled sufficiently.
According to the thermal spraying apparatus according to the third embodiment, the vicinity of the tip opening 122 of the tip nozzle 120 can be sufficiently cleaned and cooled by the fluid ejected from the tip ejection unit 144.

In each of the embodiments described above, the nozzle moving mechanism 130 linearly reciprocates the tip nozzle 120 in a direction orthogonal to the spraying direction, but the tip nozzle 120 or the dummy nozzle 150 is in an in-plane orthogonal to the spraying direction. It may be rotated and moved by.
Two or more tip nozzles 120 can be moved, and a plurality of spraying main body portions 110 are arranged to perform spraying at a plurality of locations at the same time, or tip nozzles 120 having different cross-sectional shapes of the tip opening 122 are prepared, and spraying with different modes You may make it perform.

  In each of the embodiments described above, the cleaning mechanism 140 has the ejection nozzle 141 inserted into the tip nozzle 120 and ejects a fluid for cleaning / cooling from the ejection hole 142. When the circular portion is long in the cross-sectional shape of 121, as shown in FIG. 7, a brush unit 143 including brushes 145 having a length corresponding to the circular cross-sectional portion of the inner surface 121 of the tip nozzle 120 is rotatably provided. Any configuration may be used as long as the inner surface 121 of the tip nozzle 120 can be efficiently cleaned in a short time.

DESCRIPTION OF SYMBOLS 100 ... Spraying apparatus 110 ... Spraying main-body part 111 ... Heating gas ejection part 112 ... Powder ejection part 113 ... Shutter part 120 ... Tip nozzle 121 ... Inner surface 122 ... Tip opening 130 ... nozzle moving mechanism 131 ... reciprocating member 132 ... nozzle support member 140 ... cleaning mechanism 141 ... jet nozzle 142 ... jet hole 143 ... brush unit 144 ...・ Tip ejection unit 145 ・ ・ ・ Brush 150 ・ ・ ・ Dummy nozzle Y ・ ・ ・ Thermal spray position W ・ ・ ・ Standby position

Claims (10)

A thermal spraying apparatus that has a thermal spraying main body portion and a tip nozzle and sprays powder,
The tip nozzle is configured to be separable from the thermal spray main body,
Have a nozzle moving mechanism for moving the tip nozzle to spray position and the standby position,
A thermal spraying apparatus comprising: a shutter part that cuts out powder in a predetermined amount upstream of the powder flow path of the thermal spraying main body part . The thermal spraying device according to claim 1 , further comprising a cleaning mechanism that cleans the tip nozzle located at the standby position. The thermal spraying device according to claim 2 , wherein the cleaning mechanism includes a jet nozzle that is inserted into the tip nozzle and jets a fluid. The ejection nozzle has one or more ejection holes for ejecting fluid;
The thermal spraying device according to claim 3 , wherein when the fluid is ejected toward the inner surface of the tip nozzle, the ejection hole is set to face in a direction opposite to the thermal spraying direction. The thermal spraying apparatus according to claim 2 , wherein the cleaning mechanism includes a brush unit that cleans an inner surface of the tip nozzle. The cleaning mechanism, the outlet side of the tip nozzle abuts, according to any one of claims 2 to 5, characterized in that it has a tip ejection unit for ejecting a fluid towards the inside of the tip nozzle Thermal spray equipment. The thermal spraying device according to any one of claims 1 to 6 , wherein a plurality of the tip nozzles are provided including dummy nozzles that are not used for thermal spraying. The thermal spraying apparatus according to any one of claims 1 to 7 , wherein the nozzle moving mechanism moves the end nozzle end face and the thermal spraying main body in a state of being aligned with each other. A thermal spraying method in which powder is sprayed by a thermal spraying device,
The thermal spraying device has a thermal spray main body part and a tip nozzle configured to be separable from the thermal spray main body part,
Moving the tip nozzle between a spraying position and a standby position;
There rows sprayed by the tip nozzle in the spraying position,
The thermal spraying device has a cleaning mechanism for cleaning the tip nozzle;
The thermal spraying method , wherein the tip nozzle is cleaned by the cleaning mechanism at the standby position . The thermal spraying device has a plurality of tip nozzles movable between a thermal spraying position and a standby position;
The thermal spraying method according to claim 9 , wherein the thermal spraying by the tip nozzle at the spraying position and the cleaning of the other tip nozzle at the standby position are performed in parallel.

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