JP5262861B2 - Thermal spray coating apparatus and power feeding method to wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize energization state and also to extend the service life of an electrode while maintaining the stable contact state of a contact tip with a wire to be fed according to the advance of thermal spraying. <P>SOLUTION: In an apparatus for forming a thermally spray deposit film, a wire 3 is fed to a center of a thermal spraying gun 2 according to the advance of thermal spraying, plasma is generated between a pair of electrodes, gas to be jetted from a gas jet hole 14 is burned by the plasma to melt the wire 3, and a molten metal is jetted toward an object to be thermal-sprayed to form the spray deposit film with the molten metal being thermal spraying flame with atomizing air to be jetted from air jetting holes 18 formed around the gas jetting hole 14. This apparatus for forming the thermally spray deposit film has a tip 15 slidably in a branched flow passage 20 branched from the air feeding passage 19 and formed in the direction orthogonal to the feeding direction of the wire 3, and presses and urges a contact tip 15 against the wire 3 with the pressure of the atomizing air to be blown into the branched flow passage 20. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a thermal spray coating forming apparatus for forming a thermal spray coating by spraying a molten thermal spray material toward a sprayed object, and a method for supplying power to a wire.

  For example, a wire that is a thermal spray material is fed to the center of a rotating thermal spray gun as the thermal spray progresses, and the plasma is sprayed around the periphery of the plasma generator toward the wire to melt the wire and form a droplet. There has been proposed a thermal spray coating forming apparatus that forms a thermal spray coating by spraying the sprayed metal on the object to be sprayed (for example, described in Patent Document 1).

  The thermal spray coating forming apparatus described in Patent Document 1 employs a structure in which a contact chip (wire electrode) is brought into contact with a wire to be fed, and plasma is generated by energizing the wire through the contact chip. Yes.

JP 2008-1922 A

  However, in the structure described in Patent Document 1, since the wire feed speed is changed in accordance with the progress of thermal spraying and the wire is fed, the contact portion between the contact tip (electrode) and the wire slides and erodes. It becomes worn and the energized state becomes unstable. In particular, as in Patent Document 1, in a structure in which a contact tip is fixed in a wire guide hole for guiding a wire, when the contact tip is worn, it may be impossible to contact the wire.

  Therefore, the present invention provides a thermal spray coating forming apparatus and a wire capable of stabilizing a current-carrying state by maintaining a stable contact state of a contact tip with respect to a wire fed in accordance with the progress of thermal spraying, and extending an electrode life. The purpose is to provide a method for supplying power to the power supply.

  In the thermal spray coating apparatus of the present invention, the gas or atomized air supplied to the gas ejection hole or air ejection hole receives the pressure of the gas or atomized air, moves forward, contacts the wire fed to the thermal spray gun, A contact tip that always maintains contact with the wire while being supplied is used as one electrode, and an electrode provided in the vicinity of the gas ejection hole is used as the other electrode.

  In the power supply method to the wire according to the present invention, the contact tip is brought into contact with the supplied wire and supplied with the pressure of the gas supplied to the gas ejection hole or the atomized air supplied to the air ejection hole.

  According to the thermal spray coating forming apparatus of the present invention, the contact tip serving as one of the electrodes is moved forward by receiving the pressure of the gas supplied to the gas ejection holes or the pressure of the atomized air supplied to the air ejection holes. The contact tip can always be brought into contact with the wire by the pressure of the gas or the atomizing air while the gas or the atomizing air is supplied, so that the contact state between the wire and the contact tip is maintained. Can be stabilized.

  According to the power feeding method to the wire of the present invention, the contact tip is brought into contact with the fed wire with the pressure of the gas supplied to the gas ejection hole or the atomized air supplied to the air ejection hole. Alternatively, the contact tip can be easily brought into contact with the wire by the pressure of atomizing air, and the contact state between the wire and the contact tip can be stabilized.

FIG. 1 is an overall view of a thermal spray coating forming apparatus. FIG. 2 is an enlarged cross-sectional view of a main part of the thermal spray gun in the first embodiment. FIG. 3 is an enlarged cross-sectional view of a main part of the thermal spray gun in the second embodiment. FIG. 4 is an enlarged cross-sectional view of a main part of the thermal spray gun in the third embodiment.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

“Embodiment 1”
FIG. 1 is an overall view of a thermal spray coating forming apparatus, and FIG. 2 is an enlarged cross-sectional view of a main part of a thermal spray gun in the first embodiment.

  The thermal spray coating forming apparatus 1 includes a thermal spray gun 2 that injects molten metal toward a sprayed object, a wire supply unit that supplies a wire 3 to the thermal spray gun 2, and a gas (plasma gas) that is supplied to the thermal spray gun 2. Gas supply means, air supply means for supplying atomized air to the spray gun 2, and plasma generation means for generating plasma are provided.

  The thermal spray gun 2 is attached to the tip of the main shaft 4 for turning (rotating) the thermal spray gun 2. The main shaft 4 transmits the rotational force from the motor 6 provided in the housing 5 via the timing belt 7 to rotate the thermal spray gun 2 attached to the tip thereof. In FIG. 1, the motor 6 rotates the thermal spray gun 2 in the direction indicated by the arrow X. A wire 3 serving as a thermal spray material is fed to the center of the thermal spray gun 2 through a workpiece feed hole 8 formed through the main shaft 4 in the axial direction. The work feed hole 8 is formed as a through hole having a diameter slightly larger than the diameter of the wire 3 in order to guide and feed the wire 3.

  The wire supplying means is fed to the thermal spray gun 2 through the main shaft 4 by a wire feeding device having a roller pair or the like from a wire accommodating portion (not shown). In this wire supply means, the wire 3 is fed to the spray gun 2 by changing the feed speed of the wire 3 in accordance with the progress of spraying (in accordance with the increase or decrease of the spray amount).

  The gas supply unit and the air supply unit include a gas supply unit 9 that supplies plasma gas (gas), an air supply unit 10 that supplies atomized air, and a rotary joint 11 that is a path of gas air. The plasma gas supplied from the gas supply unit 9 and the atomized air supplied from the air supply unit 10 are supplied to the thermal spray gun 2 through respective supply paths (not shown) formed in the main shaft 4. It has become so.

  The plasma generating means has a power supply unit 12, one electrode connected to the positive electrode of the power supply unit 12, and the other electrode 13 connected to the negative electrode of the power supply unit 12. The other electrode 13 is fixed in the vicinity of the gas ejection hole 14 formed in the thermal spray gun 2. One electrode consists of a contact tip 15 that contacts the wire 3.

  The spray gun 2 is formed with a wire supply hole 16 that communicates with a work feed hole 8 formed in the main shaft 4. The wire 3 is supplied from the wire supply hole 16 formed in the spray gun 2 to the front of the gas ejection hole 14. In addition, a gas supply path 17 for supplying plasma gas from the gas supply unit 9 to the gas ejection hole 14 is formed in the thermal spray gun 2. The spray gun 2 is formed with an air supply path 19 for supplying atomized air from the air supply unit 10 to the air ejection hole 18. A plurality of air ejection holes 18 are formed so as to surround the gas ejection holes 14.

  The contact tip 15 branches off from the middle of the air supply path 19 formed in the spray gun 2 for supplying atomized air to the air ejection hole 18 and feeds the wire 3 (the direction indicated by the arrow Z in FIG. 2). It is slidable in the branch flow path 20 formed in a substantially orthogonal direction. The branch channel 20 connects the wire supply hole 16 and the air supply channel 19 described above. The contact chip 15 slidable in the branch channel 20 is made of a conductive metal member and is connected to the positive electrode of the power supply unit 12. For this reason, when the contact chip 15 contacts the wire 3, the wire 3 becomes a positive pole.

  Next, a method for forming a thermal spray coating on the object to be sprayed using the thermal spray coating apparatus configured as described above and a method for supplying power to the wire will be described.

  First, plasma gas is supplied from the gas supply unit 9 to the gas supply path 17 of the thermal spray gun 2 via the main shaft 4. Similarly, atomized air is supplied from the air supply unit 10 to the air supply path 19 of the thermal spray gun 2 via the main shaft 4. Further, the wire 3 is fed by the wire feeding means, and fed to the wire feeding hole 16 of the thermal spray gun 2 through the workpiece feeding hole 8 of the main shaft 4.

  Then, the plasma gas is ejected from the gas ejection hole 14 to the outside. On the other hand, the atomized air is jetted to the outside from the air jet holes 18 so as to surround the plasma gas jetted from the gas jet holes 14. A part of the atomized air flows into the branch flow path 20 branched from the middle of the air supply path 19. The contact tip 15 provided in the branch channel 20 is moved forward under the pressure of the atomizing air flowing into the branch channel 20 and contacts the wire 3 fed to the wire supply hole 16. Then it is pressed. While the atomizing air is supplied, the contact tip 15 always maintains a contact state with the wire 3.

  Then, in a state where the contact state between the contact tip 15 and the wire 3 is maintained, a voltage is applied between the contact tip 15 serving as one electrode and the other electrode 13 provided in the vicinity of the gas ejection hole 14 to energize. Then, plasma is generated between these electrodes. The plasma gas injected from the gas ejection holes 14 is burned by the plasma and becomes a combustion flame.

  The wire 3 is melted by the combustion flame to become a molten metal. The molten metal becomes a spray frame by atomized air sprayed from the air ejection holes 18 and is sprayed toward the sprayed material, and is formed as a sprayed coating on the surface of the sprayed material. At the time of spraying on the sprayed object, the motor 6 is driven to rotate the main shaft 4 and the spray gun 2 attached to the tip of the main shaft 4 is turned.

  The wire 3 is fed in accordance with the progress of thermal spraying on the object to be sprayed. For example, when the spraying amount increases, the wire 3 is supplied to the spraying gun 2 more, and when the spraying amount decreases, the feeding amount of the wire 3 is reduced. Thus, when the feed amount variation of the wire 3 occurs, the contact tip (electrode) fixed to the spray gun 2 as in the conventional structure is worn by sliding contact with the wire 3 or electric corrosion, and the energized state is unstable. become.

  However, in the first embodiment, even if the feeding amount of the wire 3 fluctuates, the contact tip 15 moves forward due to the pressure of the atomizing air supplied to the air ejection hole 18 and comes into contact with the wire 3. While the atomizing air is supplied, the contact state between the wire 3 and the contact tip 15 can be maintained at all times.

  Further, the contact tip 15 is worn by friction or electric corrosion with the wire 3 being fed, but is pressed and urged against the wire 3 by the pressure of atomizing air blown into the branch flow path 20 branched from the air supply path 19. Therefore, the contact state between the contact tip 15 and the wire 3 can be maintained even if worn. Therefore, according to the first embodiment, it is possible to maintain a stable contact state of the contact tip 15 with respect to the wire 3 fed in accordance with the progress of thermal spraying, stabilize the energization state, and extend the electrode life with respect to the fixed electrode. be able to.

“Embodiment 2”
FIG. 3 is an enlarged cross-sectional view of a main part of the thermal spray gun in the second embodiment. In the second embodiment, a partition member 21 that closes the branch channel 20 and bends under the pressure of atomized air is provided in the branch channel 20, and the contact chip 15 is attached to the partition member 21. The contact tip 15 and the partition member 21 are connected via a coil spring 22 which is an elastic member that pulls back the contact tip 15 from the wire 3 and maintains a non-contact state when supply of atomized air is stopped.

  The partition member 21 is formed of, for example, a rubber-based material, a thin metal material, a diaphragm, or the like, and is provided in the middle of the branch channel 20 so as to close the branch channel 20. The partition member 21 is displaced by the pressure of atomizing air flowing into the branch flow path 20, and the contact chip 15 is brought into contact with the wire 3 by the displaced external force.

  While the atomizing air is flowing into the branch flow path 20, the partition member 21 is deflected by the pressure of the atomizing air, and the contact tip 15 attached to the partition member 21 is moved forward to the wire 3. Maintain contact. When the supply of atomized air is stopped, the coil spring 22 acts to pull back the contact tip 15 from the wire 3 and maintain the non-contact state of the contact tip 15 with respect to the wire 3.

  According to the second embodiment, by providing the partition member 21 so as to close the branch flow path 20, it is possible to prevent useless loss of the atomized air supplied to the air ejection holes 18 and atomized air necessary for spraying. The injection pressure can be ensured. Further, according to the second embodiment, it is possible to prevent the atomized air from flowing out from the branch flow path 20 to the wire supply hole 16, and it is possible to prevent the spraying ignition state and the spraying quality from being adversely affected.

  Further, according to the second embodiment, the contact tip 15 and the partition member 21 are connected via the coil spring 22 that pulls the contact tip 15 back from the wire 3 and maintains a non-contact state when the supply of atomized air is stopped. When the atomizing air supply is stopped, the contact tip 15 is returned in the direction in which it is separated from the wire 3, so that the wire 3 can be easily replaced without disassembling and assembling.

“Embodiment 3”
FIG. 4 is an enlarged cross-sectional view of a main part of the thermal spray gun in the third embodiment. In the first embodiment, the contact tip 15 is brought into contact with the wire 3 using atomized air supplied to the air ejection hole 18, but in the third embodiment, the contact chip is utilized using plasma gas supplied to the gas ejection hole 14. 15 is brought into contact with the wire 3.

  Specifically, as shown in FIG. 4, the contact tip 15 is slidably provided in a branch channel 20 that is branched from the gas supply path 17 and formed in a direction substantially orthogonal to the feeding direction of the wire 3. The contact tip 15 is pressed against the wire 3 by the pressure of the plasma gas branched from the gas supply path 17 and blown into the branch flow path 20. The branch channel 20 is provided with a partition member 21 that closes the branch channel 20 and bends under the pressure of the plasma gas, and a contact chip 15 is attached to the partition member 21. The contact chip 15 and the partition member 21 are connected via a coil spring 22 that pulls the contact chip 15 back from the wire 3 and maintains a non-contact state when supply of plasma gas is stopped.

  In the third embodiment, when the plasma gas is supplied from the gas supply unit 9 to the gas supply path 17, a part of the plasma gas flows into the branch flow path 20 branched from the gas supply path 17, and the pressure of the plasma gas is increased. The partition member 21 is bent, and the contact tip 15 attached to the partition member 21 is moved forward to maintain the contact state with the wire 3. When the supply of plasma gas is stopped, the coil spring 22 acts to pull back the contact tip 15 from the wire 3 and maintain the non-contact state of the contact tip 15 with respect to the wire 3.

  Thus, according to the third embodiment, as in the first embodiment, the contact tip 15 moves forward by receiving the pressure of the plasma gas supplied to the gas ejection hole 14 even if the feed amount of the wire 3 fluctuates. Thus, the contact state between the wire 3 and the contact chip 15 can be maintained at all times while the wire 3 is in contact with the plasma gas.

  Further, according to the third embodiment, the contact tip 15 is worn due to friction or electric corrosion with the supplied wire 3, but the wire is driven by the pressure of the plasma gas blown into the branch channel 20 branched from the gas supply channel 17. 3, the contact tip 15 and the wire 3 can be kept in contact with each other even if worn. Therefore, according to the third embodiment, it is possible to maintain a stable contact state of the contact tip 15 with respect to the wire 3 fed in accordance with the progress of thermal spraying, stabilize the energization state, and extend the electrode life with respect to the fixed electrode. be able to.

  Further, according to the third embodiment, since the partition member 21 is provided so as to close the branch flow path 20, it is possible to prevent unnecessary loss of plasma gas supplied to the gas ejection holes 14 and to be necessary for spraying. A sufficient plasma gas injection pressure can be ensured. Further, according to the third embodiment, it is possible to prevent the plasma gas from flowing out from the branch flow path 20 to the wire supply hole 16 and to prevent adverse effects on the spray ignition state and the spray quality.

  Further, according to the third embodiment, the contact tip 15 and the partition member 21 are connected via the coil spring 22 that pulls the contact tip 15 back from the wire 3 and maintains a non-contact state when the supply of plasma gas is stopped. When the supply of plasma gas is stopped, the contact tip 15 is returned in the direction of being pulled away from the wire 3, so that the wire 3 can be easily replaced without disassembling and assembling work.

  INDUSTRIAL APPLICABILITY The present invention can be used for a thermal spray coating forming apparatus that forms a thermal spray coating by spraying a molten thermal spray material toward a sprayed object.

DESCRIPTION OF SYMBOLS 1 ... Spray coating apparatus 2 ... Spray gun 3 ... Wire 4 ... Main shaft 9 ... Gas supply part 10 ... Air supply part 13 ... Electrode (other electrode)
14 ... Gas ejection hole 15 ... Contact tip (one electrode)
DESCRIPTION OF SYMBOLS 16 ... Wire supply hole 17 ... Gas supply path 18 ... Air ejection hole 19 ... Air supply path 20 ... Branch flow path 21 ... Partition member 22 ... Coil spring (elastic member)

Claims (5)

A wire serving as a thermal spray material is fed to the thermal spray gun in accordance with the progress of thermal spraying, plasma is generated between a pair of electrodes, and the gas is burned by the plasma from the gas ejection holes to melt the wire, In a spray coating apparatus for spraying molten metal with a atomized air sprayed from an air spray hole formed around a gas spray hole toward a sprayed object as a spraying frame to form a sprayed film on the surface of the sprayed object,
The gas supplied to the gas ejection hole or the pressure of atomized air supplied to the air ejection hole is moved forward to contact the wire fed to the spray gun, and in contact with the wire at the pressure The contact tip for maintaining the temperature is used as one electrode, and the electrode provided in the vicinity of the gas ejection hole is used as the other electrode. The thermal spray coating forming apparatus according to claim 1,
The contact tip branches from a gas supply path formed in the spray gun for supplying gas to the gas ejection holes or an air supply path formed in the spray gun for supplying atomized air to the air ejection holes. Gas or atomized air that is slidable in a branch passage formed in a direction substantially orthogonal to the wire feeding direction, and is branched from the gas supply passage or the air supply passage and blown into the branch passage. The thermal spray coating apparatus is characterized in that the wire is pressed and urged by the pressure of The thermal spray coating forming apparatus according to claim 2,
The branch channel is provided with a partition member that closes the branch channel and bends under the pressure of gas or atomized air, and the contact chip is attached to the partition member. Thermal spray coating device. The thermal spray coating forming apparatus according to claim 3,
The contact tip and the partition member are connected via an elastic member that pulls back the contact tip from the wire and maintains a non-contact state when supply of the gas or the atomized air is stopped. apparatus. A wire serving as a thermal spray material is fed to the thermal spray gun in accordance with the progress of thermal spraying, and a contact tip that is in contact with the wire is used as one electrode, and an electrode provided near the gas ejection hole is used as the other electrode. Electric power is generated to generate plasma, and the gas injected from the gas injection holes is burned by the plasma to melt the wire, and the molten metal is made of atomized air injected from the air injection holes formed around the gas injection holes. In the method of supplying power to the wire in the thermal spray coating forming apparatus that forms a thermal spray coating on the surface of the thermal spray by spraying toward the thermal spray as a thermal spray frame,
A method of supplying power to a wire, wherein the contact tip is brought into contact with the supplied wire with the pressure of gas supplied to the gas injection hole or atomized air supplied to the air injection hole.

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