Protective cover and plasma generator

Abstract

This protective cover protects a plasma head in a state where the emission port of the plasma head, from which plasma is emitted, is blocked. The protective cover comprises: a body that is supported so as to be removeable with respect to the plasma head; and a close contact body that blocks the emission port by making close contact with the jetting port while being deformed.　This plasma generation device comprises: a plasma head to which the protective cover is attached; a detection sensor that detects the pressure of gas supplied to the plasma head; and a notification device that issues a notification of an error on the basis of a value detected by the detection sensor in a case where the plasma head operates in a state where the emission port is blocked by the close contact body of the protective cover.

Description

[Technical field]

[0001] The present disclosure relates to a protective cover for protecting a plasma head, and a plasma generating device including a plasma head to which the protective cover is attached. [Background technology]

[0002] The following patent document describes a plasma head that ejects plasma from an ejection port. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-260597 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present specification is to improve the practicality of a protective cover that protects a plasma head that ejects plasma from an ejection port. [Means for solving the problem]

[0005] In order to solve the above problems, this specification discloses a protective cover that protects a plasma head while blocking the nozzle of the plasma head that ejects plasma, the protective cover comprising a main body that is detachably supported on the plasma head, and a contact body that is deformed and fits tightly against the nozzle to block the nozzle. Effect of the Invention

[0006] According to the present disclosure, the adhesion body deforms and adheres closely to the nozzle to block the nozzle, making it possible to protect the plasma head by blocking the nozzle without any gaps, thereby improving the practicality of the protective cover. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a plasma device. [Diagram 2] FIG. 2 is a block diagram showing a control box provided in the plasma device. [Diagram 3] FIG. 2 is a perspective view showing a plasma head. [Figure 4] 1 is a cross-sectional view of the plasma head cut in the X direction and the Z direction at the positions of the electrodes and the plasma passage on the main body side. [Diagram 5] FIG. 5 is a cross-sectional view taken along line AA in FIG. [Figure 6] FIG. 2 is a perspective view showing a plasma head before a protective cover is attached. [Figure 7] FIG. 2 is a perspective view showing a plasma head with a protective cover attached. [Figure 8] FIG. 2 is a side view showing a plasma head with a protective cover attached. [Figure 9] FIG. 2 is a perspective view showing a dummy nozzle. [Figure 10] FIG. 2 is a perspective view showing a plasma head with a protective cover attached and a dummy nozzle attached. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as modes for carrying out the present invention.

[0009] The plasma device 10 is a device that generates plasma under atmospheric pressure, and as shown in Fig. 1, includes a plasma head 11, a robot 13, and a control box 15. The plasma head 11 is attached to the robot 13. The robot 13 is, for example, a serial link type robot (which can also be called an articulated robot). The plasma head 11 is capable of irradiating plasma gas while being held at the tip of the robot 13. The plasma head 11 is capable of moving three-dimensionally in response to the drive of the robot 13.

[0010] The control box 15 is mainly composed of a computer, and controls the plasma device 10. The control box 15 has a power supply unit 15A that supplies power to the plasma head 11 and a gas supply unit 15B that supplies gas to the plasma head 11. The power supply unit 15A is connected to the plasma head 11 via a power cable (not shown). The power supply unit 15A changes the voltage applied to the electrode 33 (see Figures 4 and 5) of the plasma head 11 based on the control of the control box 15.

[0011] Moreover, the gas supply unit 15B is connected to the plasma head 11 via a plurality of gas tubes 19 (three in this embodiment). The gas supply unit 15B supplies reactive gas and carrier gas, which will be described later, to the plasma head 11 under the control of the control box 15. The control box 15 controls the gas supply unit 15B, and controls the amount of gas supplied from the gas supply unit 15B to the plasma head 11, etc. As a result, the robot 13 operates under the control of the control box 15, and irradiates the workpiece W placed on the table 17 with plasma gas from the plasma head 11.

[0012] The control box 15 also includes an operation unit 15C having a touch panel 15C1 and various switches 15C2. The control box 15 displays various setting screens and operation states (e.g., gas supply state, etc.) on the touch panel 15C1 of the operation unit 15C. The control box 15 also receives various information by operation input to the touch panel 15C1 or the various switches 15C2.

[0013] 2, in addition to the power supply unit 15A, gas supply unit 15B, and operation unit 15C, the control box 15 further includes a controller 20, a control circuit 22, a pressure sensor 26, a storage device 28, and the like. The controller 20 is mainly composed of a computer including a CPU, ROM, RAM, and the like (not shown). The controller 20 reads out a control program stored in the storage device 28 and executes it on the CPU, thereby controlling the power supply unit 15A, gas supply unit 15B, and the like, thereby controlling the operation of the plasma head 11.

[0014] The controller 20 is also connected to the operation unit 15C via the control circuit 22. The controller 20 changes the display of the touch panel 15C1 of the operation unit 15C via the control circuit 22. As a result, an arbitrary image is displayed on the touch panel 15C1. The controller 20 also accepts an operation input to the operation unit 15C via the control circuit 22. The controller 20 inputs a signal indicating an operation performed on the touch panel 15C1 or various switches 15C2 of the operation unit 15C from the operation unit 15C, and determines the content of the operation input. The pressure sensor 26 detects the pressure of the gas supplied from the gas supply unit 15B to the plasma head 11. The pressure sensor 26 is connected to the controller 20, and outputs the detected value, that is, the pressure of the gas supplied to the plasma head 11, to the controller 20. As a result, the controller 20 monitors the pressure of the gas supplied to the plasma head 11.

[0015] As shown in Fig. 3, the plasma head 11 includes a plasma generating unit 30 and the like. The plasma generating unit 30 generates plasma gas by converting the processing gas supplied from the gas supply unit 15B (see Fig. 1) of the control box 15 into plasma. The plasma head 11 then ejects the plasma gas generated in the plasma generating unit 30 onto the workpiece W shown in Fig. 1. The processing gas is supplied to the plasma head 11 from the upstream side to the downstream side in the direction of the arrow shown in Fig. 3.

[0016] As shown in Figs. 4 and 5, the plasma generating unit 30 includes a housing 31, a pair of electrodes 33, a plasma irradiation unit 35, and the like. Fig. 4 is a cross-sectional view cut in accordance with the positions of the pair of electrodes 33 and a plurality of main body side plasma passages 71 described later, and Fig. 5 is a cross-sectional view taken along line AA in Fig. 4. The housing 31 is composed of a first base 36 made of a resin with high heat resistance, a second base 37 made of a resin with high heat resistance, and a ceramic member 38 made of a ceramic with high heat resistance. As shown in Fig. 3, the first base 36, the second base 37, and the ceramic member 38 are fastened together by four bolts 40 (only two are shown in the figure) and integrated together. In addition, a metal plate 46 is fastened to the back of the first base 36 constituting the housing 31 by bolts (not shown), and the plasma head 11 is attached to the robot (see Fig. 1) 13 using the metal plate 46.

[0017] In addition, in the housing 31 in which the first base 36, the second base 37, and the ceramic member 38 are integrated, a reaction chamber 51 for generating plasma gas is formed inside the ceramic member 38, as shown in FIG. 4. Each of the pair of electrodes 33 is, for example, cylindrical, and is fixed with its tip protruding into the reaction chamber 51. In the following description, the pair of electrodes 33 may be simply referred to as electrodes 33. In addition, the direction in which the pair of electrodes 33 are arranged is referred to as the X direction, the horizontal direction perpendicular to the X direction is referred to as the Y direction, and the axial direction of the cylindrical electrode 33 is referred to as the Z direction. In this embodiment, the X direction, the Y direction, and the Z direction are perpendicular to each other.

[0018] A part of the outer periphery of the electrode 33 is covered by an electrode cover 57 made of an insulator such as ceramics. The electrode cover 57 is substantially hollow and cylindrical, with openings formed at both ends in the longitudinal direction. A gap between the inner periphery of the electrode cover 57 and the outer periphery of the electrode 33 functions as a gas passage 58. The downstream opening of the electrode cover 57 is connected to the reaction chamber 51. The lower end of the electrode 33 protrudes from the downstream opening of the electrode cover 57.

[0019] In addition, a reaction gas flow passage 61 and a pair of carrier gas flow passages 63 are formed inside the first base 36 of the housing 31. The reaction gas flow passage 61 is connected to the gas supply unit 15B via a gas tube 19 (see FIG. 1), and causes the reaction gas supplied from the gas supply unit 15B to flow into the reaction chamber 51. The pair of carrier gas flow passages 63 are disposed at positions sandwiching the reaction gas flow passage 61 in the X direction. Each of the pair of carrier gas flow passages 63 is connected to the gas supply unit 15B via a gas tube 19 (see FIG. 1), and a carrier gas is supplied from the gas supply unit 15B. The carrier gas flow passage 63 causes the carrier gas to flow into the reaction chamber 51 via the gas passage 58.

[0020] As the reactive gas (seed gas), oxygen (O2) can be used. The gas supply unit 15B, for example, flows a mixed gas of oxygen and nitrogen (N2) (e.g., dry air (Air)) between the electrodes 33 of the reaction chamber 51 via the reactive gas flow passage 61. Hereinafter, for convenience, this mixed gas may be referred to as the reactive gas, and oxygen may be referred to as the seed gas. As the carrier gas, nitrogen can be used. The gas supply unit 15B flows the carrier gas from each of the gas passages 58 so as to surround each of the pair of electrodes 33.

[0021] An AC voltage is applied to the pair of electrodes 33 from the power supply unit 15A of the control box 15. By applying the voltage, for example, as shown in Fig. 4, a pseudo arc A is generated between the lower ends of the pair of electrodes 33 in the reaction chamber 51. When the reactive gas passes through this pseudo arc A, the reactive gas is turned into plasma. Therefore, the pair of electrodes 33 generates a discharge of the pseudo arc A, turns the reactive gas into plasma, and generates plasma gas.

[0022] Further, a plurality of (six in this embodiment) main body side plasma passages 71 are formed in the downstream portion of the reaction chamber 51 in the housing 31, aligned at intervals in the X direction and extending in the Z direction. The upstream ends of the plurality of main body side plasma passages 71 are connected to the reaction chamber 51.

[0023] The plasma irradiation unit 35 includes a nozzle 73 and the like. The nozzle 73 is generally T-shaped in a side view from the X direction, and is composed of a nozzle body 77 and a nozzle tip 79. The nozzle 73 is an integral body of the nozzle body 77 and the nozzle tip 79, and is made of ceramics having high heat resistance. The nozzle body 77 is generally flange-shaped and is fixed to the lower surface of the housing 31 by a bolt 80. Therefore, the nozzle 73 is detachable from the housing 31, and a nozzle of any shape can be attached to the housing 31. The nozzle tip 79 is shaped to extend downward from the lower surface of the nozzle body 77. The nozzle 73 is formed with a plurality of (six in this embodiment) nozzle-side plasma passages 81 that penetrate the nozzle body 77 and the nozzle tip 79 in the up-down direction, i.e., in the Z direction, and the plurality of nozzle-side plasma passages 81 are arranged at intervals in the X direction. The multiple nozzle-side plasma passages 81 are formed at the same positions in the Z direction as the multiple body-side plasma passages 71. Therefore, the body-side plasma passages 71 and the nozzle-side plasma passages 81 communicate with each other.

[0024] With this structure, the plasma gas generated in the reaction chamber 51 is ejected from the opening 81A at the lower end of the nozzle-side plasma passage 81 together with the carrier gas via the main body-side plasma passage 71 and the nozzle-side plasma passage 81. In this way, in the plasma head 11, a discharge occurs in the reaction chamber 51, and the plasma is generated, so that the plasma gas is ejected from the tip of the nozzle 73, and the workpiece W is subjected to plasma processing. At this time, the discharge in the reaction chamber 51 may carbonize the inner wall surface of the housing 31 that defines the reaction chamber 51, the electrode 33, etc., and foreign matter may be generated. If foreign matter is generated in the reaction chamber 51 in this way, the foreign matter may clog the main body-side plasma passage 71, the nozzle-side plasma passage 81, etc., and the amount of plasma irradiation may decrease, and plasma may not be ejected from the nozzle 73.

[0025] For this reason, the pressure sensor 26 is provided in the plasma device 10. That is, when foreign matter clogs the main body side plasma passage 71, the nozzle side plasma passage 81, etc., the internal pressure of the reaction chamber 51 rises. Then, the internal pressure of the gas supply unit 15B that supplies gas to the plasma head 11 also rises. As described above, the gas supply unit 15B is provided with the pressure sensor 26, which detects the pressure of the gas supplied from the gas supply unit 15B to the plasma head 11. For this reason, when the pressure detected by the pressure sensor 26 exceeds a predetermined pressure, the controller 20 displays a warning screen on the touch panel 15C1. This allows the operator to recognize the abnormality and inspect the plasma device 10, thereby ensuring appropriate plasma processing by the plasma device 10.

[0026] In addition, because the discharge in the reaction chamber 51 causes the reaction chamber 51 to become hot, the ceramic member 38 of the housing 31 in which the reaction chamber 51 is formed is made of ceramic with high heat resistance. However, although ceramic is a material with high heat resistance, it is also brittle and easily damaged. For this reason, there is a risk that the ceramic member 38 of the plasma head 11 may come into contact with something and be damaged when the plasma head 11 is shipped or when the plasma head 11 is attached to the robot 13. In view of this, the manufacturer of the plasma head 11 ships the plasma head 11 with a protective cover attached to it.

[0027] In detail, when the plasma head 11 is shipped, the nozzle 73 is removed from the plasma head 11 as shown in Fig. 6. That is, in the plasma head 11 shown in Fig. 3, the bolt 80 is removed and the nozzle 73 of the plasma irradiation unit 35 is removed from the housing 31 of the plasma head 11. Then, the nozzle 73 is packed separately from the plasma head 11. Meanwhile, in the plasma head 11 from which the nozzle 73 is removed, the lower end of the main body side plasma passage 71 and the screw hole 90 for fastening the bolt 80 are exposed on the lower surface of the housing 31 as shown in Fig. 6. Then, a protective cover 100 is attached to the plasma head 11 so as to cover the lower end of the main body side plasma passage 71 and the lower surface of the housing 31 where the screw hole 90 is exposed.

[0028] In detail, the protective cover 100 is composed of a cover body 102 detachably supported by the plasma head 11, and a sponge material 104 that closes the main body side plasma passage 71 while being in close contact with the lower end of the main body side plasma passage 71. The cover body 102 is a plate-shaped steel material bent into a generally U-shape, and is composed of a pair of opposing opposing surfaces 106, 108 and a connecting surface 110 that connects the lower edges of the pair of opposing surfaces 106, 108. The dimension of the connecting surface 110 of the protective cover 100 is slightly larger than the dimension of the lower surface of the housing 31, that is, the dimension of the lower surface of the ceramic member 38, and the dimension of the opposing surface 106 is approximately the same as the dimension of the second base 37 of the housing 31 and the side wall surface on the front side of the ceramic member 38. In addition, the dimension of the opposing surface 108 in the width direction is approximately the same as the dimension of the opposing surface 106 in the width direction, but the dimension of the opposing surface 108 in the height direction is longer than the dimension of the opposing surface 106 in the height direction. Two through holes 112 are formed side by side in the left-right direction at the upper end of the opposing surface 108. A generally plate-shaped sponge material 104 is fixed to the upper surface of the connecting surface 110. The sponge material 104 is made of closed-cell polyurethane.

[0029] The protective cover 100 having such a configuration is attached to the plasma head 11 so as to cover the ceramic member 38 of the plasma head 11, as shown in Fig. 7 and Fig. 8. More specifically, the protective cover 100 is disposed in such a state that the connecting surface 110 faces the lower surface of the ceramic member 38, the facing surface 106 faces the front side wall surface of the housing 31, and the facing surface 108 faces the rear side wall surface of the housing 31. By disposing the protective cover 100 in this state, the sponge material 104 fixed to the connecting surface 110 is in an elastically deformed state and adheres closely to all of the plurality of main body side plasma passages 71 opening on the lower surface of the ceramic member 38. In addition, the upper end of the facing surface 108 of the protective cover 100 disposed in this state faces the lower end of the metal plate 46 fixed to the rear surface of the first base 36 of the housing 31, and the lower end of the metal plate 46 has two screw holes (only one is shown in Fig. 8) 116 formed at positions facing the two through holes 112. Two bolts 118 are inserted through the two through holes 112 in the opposing surface 108 and fastened to the two screw holes 116. As a result, the protective cover 100 is attached to the plasma head 11 in a state in which the entire lower surface of the ceramic member 38 is covered by the connecting surface 110 and the entire front and rear side wall surfaces of the ceramic member 38 are covered by the opposing surfaces 106, 108. As a result, the lower surface, front side wall surface, and rear side wall surface of the ceramic member 38 are covered by the protective cover 100, thereby preventing damage to the ceramic member 38.

[0030] Also, a dummy nozzle 120 shown in Fig. 9 can be attached to the protective cover 100. The dummy nozzle 120 has approximately the same shape and dimensions as the nozzle 73. However, as described above, the nozzle 73 is made of ceramic, while the dummy nozzle 120 is made of resin. Two screw holes (see Fig. 7) 122 are formed in the lower surface of the connecting surface 110 of the protective cover 100, and the dummy nozzle 120 is fixed to the lower surface of the cover body 102 of the protective cover 100 by fastening two bolts 126 into the two screw holes 122, as shown in Fig. 10.

[0031] In this way, by attaching the dummy nozzle 120 to the lower surface of the cover body 102 of the protective cover 100, the teaching of the plasma head 11 can be performed in a state where the damage of the nozzle 73 is prevented. In detail, in the plasma head 11, when the plasma is actually irradiated to the workpiece W, the plasma is ejected from the nozzle 73. For this reason, it is desirable to perform the teaching of the plasma head 11 in a state where the nozzle 73 is attached to the plasma head 11. However, when the teaching of the plasma head 11 is performed, there is a risk that the nozzle 73 attached to the tip of the plasma head 11 will come into contact with the workpiece W, the table 17, etc. As described above, the nozzle 73 is made of ceramic and is easily damaged. For this reason, if the teaching of the plasma head 11 is performed in a state where the nozzle 73 is attached to the plasma head 11, there is a risk that the nozzle 73 will be damaged.

[0032] In view of this, it is possible to attach a dummy nozzle 120 made of resin to the protective cover 100. That is, in a state where the protective cover 100 is attached to the plasma head 11, the dummy nozzle 120 is attached to the connecting surface 110 of the protective cover 100. In this way, by attaching the dummy nozzle 120 having approximately the same shape and approximately the same dimensions as the nozzle 73 to the lower surface of the protective cover 100 that covers the lower surface of the plasma head 11 and performing teaching, it is possible to perform teaching equivalent to the case where teaching is performed in a state where the nozzle 73 is attached to the plasma head 11. In addition, since the dummy nozzle 120 is made of resin, even if the dummy nozzle 120 abuts against the workpiece W or the like during teaching, the dummy nozzle 120 is unlikely to be damaged. As a result, by attaching the dummy nozzle 120 to the lower surface of the cover body 102 of the protective cover 100, it is possible to perform high-quality teaching of the plasma head 11 while preventing damage to the nozzle 73.

[0033] Furthermore, when the plasma head 11 actually performs the plasma processing, the operator must remove the protective cover 100 from the plasma head 11 and attach the nozzle 73 to the plasma head 11. That is, as shown in FIG. 3, the nozzle 73 must be attached to the lower surface of the ceramic member 38 from which the protective cover 100 has been removed. However, when the protective cover 100 and the dummy nozzle 120 are attached to the plasma head 11, as can be seen by comparing FIG. 3 with FIG. 10, the plasma head 11 to which the nozzle 73 is attached and the plasma head 11 to which the protective cover 100 and the dummy nozzle 120 are attached have similar appearances. For this reason, the operator may forget to remove the protective cover 100 from the plasma head 11 before the plasma processing is performed by the plasma head 11. In such a case, the plasma processing is performed by the plasma head 11 with the protective cover 100 attached, but the workpiece W is naturally not irradiated with plasma, so that appropriate plasma processing cannot be ensured.

[0034] In view of this, the protective cover 100 is provided with a sponge material 104. More specifically, when the protective cover 100 is attached to the plasma head 11, the sponge material 104 is in an elastically deformed state and adheres closely to all of the plurality of main body side plasma passages 71 opening on the lower surface of the ceramic member 38, as described above. As a result, all of the openings of the plurality of main body side plasma passages 71 are blocked by the sponge material 104. In addition, since the sponge material 104 is formed of polyurethane with closed cells, it has a high sealing effect and does not allow gas to pass through. Therefore, when plasma processing is performed by the plasma head 11 with the protective cover 100 attached, the plasma generated in the reaction chamber 51 is not discharged from the main body side plasma passage 71, so the internal pressure of the reaction chamber 51 increases. At this time, the internal pressure of the gas supply unit 15B that supplies gas to the plasma head 11 also increases, and the pressure detected by the pressure sensor 26 exceeds a predetermined pressure, causing a warning screen to be displayed on the touch panel 15C1. This allows the worker to recognize the abnormality and, by inspecting the plasma device 10, realize that he or she has forgotten to remove the protective cover 100 from the plasma head 11. In this way, by attaching the sponge material 104 to the protective cover 100, the worker can be made aware that he or she has forgotten to remove the protective cover 100.

[0035] As described above, the pressure sensor 26 is for monitoring the pressure rise inside the reaction chamber 51 due to clogging by foreign matter or the like, and a configuration for displaying a warning screen on the touch panel 15C1 when the pressure detected by the pressure sensor 26 exceeds a predetermined pressure has been conventionally provided in the plasma device 10. Therefore, by simply attaching the sponge material 104 to the protective cover 100, it is possible to make the operator realize that he or she has forgotten to remove the protective cover 100 by utilizing the conventional configuration for displaying the warning screen.

[0036] Incidentally, the plasma device 10 is an example of a plasma generating device. The plasma head 11 is an example of a plasma head. The touch panel 15C1 is an example of an alarm device. The pressure sensor 26 is an example of a detection sensor. The opening of the main body side plasma passage 71 on the lower surface of the ceramic member 38 is an example of an ejection port. The nozzle 73 is an example of an ejection nozzle. The protective cover 100 is an example of a protective cover. The cover main body 102 is an example of a main body. The sponge material 104 is an example of a contact body. The opposing surfaces 106, 108 are examples of opposing surfaces. The connecting surface 110 is an example of a connecting surface. The dummy nozzle 120 is an example of a dummy nozzle. The screw hole 122 is an example of an attachment portion.

[0037] As described above, the present embodiment has the following advantages.

[0038] The protective cover 100, which protects the ceramic member 38 while blocking the opening of the main body side plasma passage 71 of the plasma head 11, is composed of a cover body 102 that is detachably supported on the plasma head 11, and a sponge material 104 that blocks the opening when it is deformed into the opening of the main body side plasma passage 71. This allows the protective cover 100 to be easily attached to the plasma head 11, and also allows the opening of the main body side plasma passage 71 to be blocked without any gaps.

[0039] Moreover, the cover body 102 of the protective cover 100 is U-shaped, which allows the ceramic member 38 to be appropriately protected by the cover body 102, which has a simple structure and is inexpensive.

[0040] The U-shaped cover body 102 is composed of a pair of opposing surfaces 106, 108 and a connecting surface 110 that connects the edges of the pair of opposing surfaces 106, 108, and the sponge material 104 is disposed on the connecting surface 110. This clarifies the structure of the protective cover 100.

[0041] Furthermore, the protective cover 100 is attached to the plasma head 11 with the pair of opposing surfaces 106, 108 facing the front and rear side wall surfaces of the plasma head 11 and the connecting surface 110 facing the underside of the ceramic member 38 of the plasma head 11. This allows the protective cover 100 to adequately protect the ceramic member 38, and the sponge material 104 to adequately block the opening of the main body side plasma passage 71.

[0042] Furthermore, a dummy nozzle 120 is detachably attached to a screw hole 122 of the protective cover 100. This makes it possible to prevent damage to the nozzle 73 when teaching of the plasma head 11 is performed.

[0043] In addition, in the plasma device 10, when the plasma head 11 is operated with the protective cover 100 attached to the plasma head 11, that is, with the opening of the main body side plasma passage 71 blocked by the sponge material 104, a warning screen is displayed on the touch panel 15C1 when the pressure detected by the pressure sensor 26 exceeds a predetermined pressure. This makes it possible to notify the operator that the protective cover 100 has been left unattached.

[0044] The present disclosure is not limited to the above embodiment, and can be embodied in various forms with various modifications and improvements based on the knowledge of a person skilled in the art. Specifically, for example, the sponge material 104 of the protective cover 100 is formed of closed-cell urethane foam, but may be formed of various resins such as closed-cell polyethylene. The sponge material may be formed of open-cell resin without being limited to closed-cell resin. However, when the sponge material is formed of open-cell resin, even if the opening of the main body side plasma passage 71 is blocked by the sponge material, plasma may leak through the open cells. For this reason, when the sponge material is formed of open-cell resin, it is preferable, for example, to melt the surface of the sponge material so that the open cells are not exposed on the surface of the sponge material. The sponge material is not limited to resin sponge material, and the opening of the main body side plasma passage 71 may be blocked by an elastic body such as rubber or gel. Furthermore, the sponge material is not limited to an elastically deformable member, and a member that blocks the opening of the main body side plasma passage 71 in a plastically deformed state may be adopted.

[0045] In addition, in the above embodiment, a U-shaped cover body 102 is used, but it is possible to use a cover body of various shapes, such as a box shape, as long as the shape is capable of protecting the ceramic member 38. In addition, in the above embodiment, the protective cover 100 that covers the ceramic member 38 when the nozzle 73 is removed is used, but it is also possible to use a protective cover that covers the ceramic member 38 when the nozzle 73 is attached. Furthermore, in the above embodiment, the protective cover 100 that protects the ceramic member 38 is used, but it is also possible to use a protective cover that protects other members.

[0046] Furthermore, in the above embodiment, when the pressure detected by the pressure sensor 26 exceeds a predetermined pressure, a warning screen is displayed on the touch panel 15C1 to notify the operator of the occurrence of an abnormality, but the occurrence of an abnormality may also be notified to the operator by various methods such as sound or light. [Explanation of symbols]

[0047] 10: Plasma device (plasma generator) 11: Plasma head 15C1: Touch panel (alarm device) 26: Pressure sensor (detection sensor) 71: Plasma passage on main body side (nozzle) 73: Nozzle (nozzle) 100: Protective cover 102: Cover body (main body) 104: Sponge material (adhering body) 106: Opposing surface 108: Opposing surface 110: Connection surface 120: Dummy nozzle 122: Screw hole (mounting part)

Claims

1. A protective cover for protecting a plasma head in a state where a nozzle of the plasma head that ejects plasma is blocked, a main body that is detachably supported by the plasma head; a contact body that is in a deformed state and comes into close contact with the nozzle to block the nozzle; A protective cover.

2. The protective cover of claim 1 , wherein the body is U-shaped.

3. The U-shaped main body is The plate is made up of a pair of opposing surfaces and a connecting surface that connects edges of the pair of opposing surfaces. The protective cover according to claim 2 , wherein the contact body is disposed on the connecting surface.

4. The protective cover according to claim 3, which is attached to the plasma head with the pair of opposing surfaces facing a pair of side wall surfaces of the plasma head and the connecting surface facing a lower surface of the plasma head on which the nozzle is formed.

5. 5. The protective cover according to claim 1, further comprising a mounting portion to which a dummy nozzle of the ejection nozzle is detachably mounted.

6. The plasma head to which the protective cover according to any one of claims 1 to 5 is attached; a detection sensor for detecting the pressure of a gas supplied to the plasma head; an alarm device that notifies an error based on a detection value of the detection sensor when the plasma head is operated in a state where the nozzle is blocked by the contact body of the protective cover; A plasma generating device comprising:

Images