JP4689564B2 - Fuel injection valve manufacturing apparatus and manufacturing method - Google Patents

Description

  The present invention relates to a fuel injection valve manufacturing apparatus and manufacturing method in an internal combustion engine, and more particularly to a fuel injection valve manufacturing apparatus and manufacturing method suitable for a direct injection engine.

  Conventionally, in fuel injection valves of direct injection engines, a product called “deposit” adheres to the tip of the valve exposed in the combustion chamber during incomplete combustion of the fuel, causing problems such as clogging of the nozzle pores. It is easy to produce. For this reason, a method for manufacturing a fuel injection valve that minimizes the adhesion of products generated in the combustion chamber to the tip of the fuel injection valve has been proposed (see Patent Document 1).

This is because when a coating for preventing deposition of deposits on the inner wall of the orifice at the tip of the fuel injection valve is applied, a masking jig is first installed to prevent the coating from adhering to the valve seat. A method is described for removing the tool, then re-grinding the valve seat and assembling the fuel injection valve in combination with a separately formed needle.
JP 2002-543330 A

  However, in the above conventional example, the masking jig is removed after coating, and the regrinding work is performed to improve the sealing of the valve seat, and the work of removing the masking jig and the precision regrinding work are required. In addition, the working efficiency is lowered, and there is a possibility that the coating applied to the side wall in the corner orifice at the time of re-polishing the valve seat may be damaged by the re-polished shavings.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel injection valve manufacturing apparatus and a manufacturing method capable of efficiently performing a coating only at a necessary portion.

  The present invention relates to an apparatus and a method for manufacturing a fuel injection valve for an internal combustion engine, in which a film for preventing deposit adhesion is formed on the surface of the nozzle plate exposed to the combustion chamber of the valve device, the tip surface of the needle, and the inner surface of the injection hole. A plurality of holding holes which are arranged on the cathode electrode of the coating apparatus and open to the surface facing the anode electrode of the coating apparatus, and at least the nozzle plate or nozzle of the valve apparatus inside. Parts that can be integrated with the plate can be accommodated, and the surface of the nozzle plate exposed to the combustion chamber of the valve device of the fuel injection valve is respectively connected to the anode electrode of the film processing apparatus from the opening surface of the plurality of holding holes. Retained so that they face each other and can position the nozzle plate of multiple valve devices or parts integrated with the nozzle plate It was to prepare for a location.

  Therefore, according to the present invention, a plurality of holding holes that can be arranged on the cathode electrode of the film processing apparatus and open on the surface facing the anode electrode of the film processing apparatus are aligned, and at least the nozzle plate of the valve apparatus is provided inside. Alternatively, a part integrated with the nozzle plate can be accommodated, and the surface of the nozzle plate exposed to the combustion chamber of the valve device of the fuel injection valve is moved from the opening surface of the plurality of holding holes to the anode electrode of the film processing apparatus. A large number of workpieces need coating in the coating processing equipment by using a holding device that can position the nozzle plate of multiple valve devices or parts integrated with the nozzle plate so that they are exposed to face each other. Since the nozzle plate surface, needle tip surface and injection hole inner surface are held facing the anode electrode, a coating is required. That the nozzle plate surface, collectively the needle tip surface and the injection hole inner surface can coating, cost reduction can be achieved. At the same time, since a large amount of work is stably held without unevenness, the film thickness of the obtained film can be kept constant, and the film quality can be improved.

  Hereinafter, an embodiment of a fuel injection valve manufacturing apparatus and method according to the present invention will be described with reference to FIGS. 1 to 4 are sectional views for explaining the structure of a fuel injection valve to which the manufacturing apparatus and the manufacturing method of the present invention are applied, and FIGS. 5 to 6 are coating films that are the fuel injection valve manufacturing apparatus of the present embodiment. FIG. 7 to FIG. 20 are explanatory diagrams and process diagrams for explaining a holding device which is a manufacturing apparatus for a fuel injection valve according to this embodiment, and FIG. 21 is a process showing a coating process by a coating processing apparatus. 22 and 24 are cross-sectional views showing second and third embodiments of the holding device.

  First, the structure of the fuel injection valve 1 will be described with reference to FIGS. The fuel injection valve 1 is mainly used in a fuel supply type engine that injects fuel into a combustion chamber of an engine, and is provided on a housing 2 and a front end side of the housing 2 as shown in FIG. A valve device 3 and a solenoid device 4 for driving the valve device 3 are provided. Although not shown, the fuel injection valve 1 is fixed to the cylinder head in a state in which a tip portion for injecting fuel is inserted into an injection valve insertion hole provided in the combustion chamber of the internal combustion engine. Then, high-pressure fuel is supplied to the inside from a fuel supply pipe (not shown).

  As shown in FIG. 2, the valve device 3 includes a cylindrical nozzle housing 5 fixed to the distal end side of the housing 2, a nozzle plate 6 fixed to the distal end side of the nozzle housing 5, and the nozzle plate 6 is provided with a valve body 7 that is seated on 6 and a plunger rod 8 that is provided with a valve body 7 at its tip and that connects a base portion 8A to an armature 10 of a solenoid device 4 to be described later. The valve body 7 and the plunger rod 8 are integrated, and may be collectively referred to as a needle 13. The cylindrical nozzle housing 5 includes a small-diameter portion 5A on the front end side and a large-diameter portion 5B on the rear end side, and includes a nozzle plate 6 at the tip of the small-diameter portion 5A and is provided on the inner periphery of the large-diameter portion 5B. The plunger rod 8 is slidably held by the spacer 5C.

  The nozzle plate 6 is fixed to the inner surface of the small diameter portion 5A in a state where the outer peripheral surface is closely fitted to the small diameter portion 5A of the nozzle housing 5, and the inner peripheral side has a small diameter injection hole (nozzle) 6A from the tip side. And a tapered valve seat 6B on which the valve body 7 is seated so that the inner diameter is gradually enlarged in continuation with the injection hole 6A. On the back surface of the nozzle plate 6, an annular overflow generator 9 having an outer periphery fixed to the inner peripheral surface of the small diameter portion 5A of the nozzle housing 5 is disposed. The overflow generator 9 sprays the spray during fuel injection. Give a pattern. As shown in FIG. 3, the valve body 7 is formed in a tapered shape at the tip of the plunger rod 8, and is configured to be seated on the valve seat 6 </ b> B of the nozzle plate 6. As shown in FIG. 4, the valve body 7 may be configured to be seated on the valve seat 6 </ b> B of the nozzle plate 6 as a substantially spherical body at the distal end of the plunger rod 8.

  As shown in FIG. 1, the solenoid device 4 is connected to a plunger rod 8 base 8 </ b> A of the valve device 3, and is fixed in the housing 2 and an armature 10 that is slidably inserted in the housing 2. A hollow core 11 and a coil 12 fitted to the outer periphery of the core 11 and inserted into the housing 2. The housing 2 surrounds the coil 12 and makes contact with the outer periphery of the armature 10 and the core 11, thereby constituting a magnetic circuit.

  The armature 10 is urged toward the valve device 3 by a spring (not shown), and the valve body 7 is seated on the valve seat 6 </ b> B of the nozzle plate 6 via the plunger rod 8. Further, when a drive current is supplied to the coil 12, the magnetic circuit is formed, and the armature 10 is driven to the core 11 side against a spring (not shown) and brought into contact with the core 11, thereby The valve body 7 of the device 3 is separated from the valve seat 6B of the nozzle plate 6 and functions to open the valve device 3.

  The combustion chamber side end surface 6C of the nozzle plate 6 and the inner surface of the fuel injection hole 6A (orifice) of the valve device 3 of the fuel injection valve 1 having the above-described configuration and the tip surface of the valve body 7 have a " Since a product called “deposit” adheres, a coating 15 for preventing deposit adhesion is applied to these surfaces as shown in FIG. The coating 15 is composed of a carbon coating. Further, the carbon thin film 15 contains fluorine (F) and has a thickness of 10 μm or less. In this way, by providing the carbon thin film 15 at the fuel contact portion, carbon (such as soot generated during combustion of deteriorated gasoline or engine oil), fuel soaked in these, etc., adhere as deposits. Therefore, good fuel spray characteristics can be maintained for a long time. Moreover, when the carbon film 15 contains fluorine, stacking of deposits is further suppressed.

  The coating 15 is formed by coating the nozzle plate 6 with a carbon coating by a vapor deposition method. As a result, a uniform and thin film can be formed, and there is no concern about corrosion of the pores and the sealing surface unlike the plating method. In addition, since the sneak adhesion to the inside of the injection hole 6A is less than that in the liquid phase method, the masking on the valve seat 6B, which is required in the liquid phase film formation, is unnecessary. As the vapor deposition method, for example, a plasma CVD method is preferably employed. At this time, many fluorine atoms can be taken into the carbon coating. Further, the film can be formed under a lower temperature condition. When the plasma CVD method is employed, it is preferable to use a hydrocarbon gas and a fluorine-based gas as the carbon coating gas.

Examples of the hydrocarbon gas include methane (CH ₄ ), ethane (C ₂ H ₆ ), propane (C ₃ H ₈ ), butane (C ₄ H ₁₀ ), acetylene (C ₂ H ₂ ), and benzene (C ₆ H ₆ ), cyclohexane (C ₆ H ₁₂ ) and the like can be used. The fluorine-based gas includes fluorine (F ₂ ), nitrogen trifluoride (NF ₃ ), sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), carbon difluoride (C _2). F _6), 8 fluoride 4 carbon (C ₄ F _{8), 4} silicon fluoride (SiF _4), 6 silicon fluoride (Si ₂ F _6), 3 chlorine fluoride (ClF _3), hydrogen fluoride (HF ) Etc. can be used.

  FIG. 5 shows a film processing apparatus for performing a film processing by a plasma CVD method. An exhaust pump 21 for exhausting to a vacuum and a cylinder 28 for supplying gas are connected to the vacuum exhaust chamber 20. A pressure adjustment valve 22 is installed between the exhaust pump 21 and the chamber 20 so that the inside of the chamber 20 can be adjusted to a predetermined pressure. An MFC (flow rate regulator) 27 is installed between the cylinder 28 and the chamber 20 to control a predetermined gas flow rate. A ground electrode 23 and a high-frequency electrode 25 are installed in the chamber 20, and a large number of valve devices 3 are arranged and installed on the high-frequency electrode 25 while being held by a dedicated holding device 16 as will be described later. The high frequency electrode 25 is supplied with high frequency power from a high frequency power supply 30 via a matching box 29. As a result, plasma is generated between the installation electrode 23 and the high-frequency electrode 25. The high-frequency electrode 25 is desirably water-cooled in order to suppress a temperature rise.

  FIG. 6 shows an outline of the layout of the valve device 3 in the plasma CVD apparatus (film processing apparatus), and the nozzle plate 6 is attached so that the exposed surface 6C of the nozzle plate 6 to the combustion chamber faces the anode electrode 23. The nozzle housing 5 is disposed in an inverted state. In the nozzle housing 5, the plunger rod 8 may be similarly inverted and placed with the valve body 7 seated on the valve seat 6 </ b> B of the nozzle plate 6.

  FIG. 7 shows a perspective view of the holding device 16 (first embodiment) of the valve device 3 placed on the cathode electrode 25. The cathode electrode 25 is disposed below the apparatus corresponding to the anode electrode 23 of the plasma CVD apparatus which is a film processing apparatus, and is formed in a disk shape as in the illustrated example. Although not illustrated, cooling means such as water cooling is provided. Is installed. First, the holding device 16 of the valve device 3 is positioned on the cathode electrode 25 and the heat insulating layer 17 is disposed so that heat does not escape from the lower part of the workpiece (valve device 3) to the cathode electrode 25 side. A needle holder 18 is stacked thereon, and a plurality of needles 13 are arranged and held on the needle holder 18, and the valve housing 5 with the nozzle plate 6 is put on the valve seat 6 </ b> B over the held needles 13. A housing holder 19 is laminated above the needle holder 18 so as to be seated on the valve body 7 and to position the valve housing 5.

  The configuration and installation procedure of the heat insulating layer 17, the needle holder 18 and the housing holder 19 of the holding device 16 including the installation procedure of the valve device 3 will be described below with reference to FIGS. For convenience of explanation, the cathode electrode 25 is described as being assembled in order. However, the cathode electrode 25 is installed in a plasma CVD apparatus, and includes a heat insulating layer 17, a needle holder 18, and a housing. After the workpiece 3 is held by the holding device 16 configured by combining the holding tools 19, these are installed on the cathode electrode 25 installed in the plasma CVD apparatus.

  As shown in FIG. 8, the heat insulating layer 17 includes a cylindrical frame body 17A and a lid body 17B on the upper side of the frame body 17A, which are integrally fixed, and a resin spacer made of a heat insulating material in the internal space. Fill with 17C. The lower end surface of the frame 17A is provided with positioning protrusions 17D arranged at equal intervals in the circumferential direction. By engaging the positioning protrusions 17D with positioning holes 25A provided in the cathode electrode 25, the positioning protrusions 17D are formed at the center of the cathode electrode 25. It is arranged to be located. In addition, positioning holes 17E for fitting positioning pins 33 arranged at equal intervals in the circumferential direction are also provided on the outer peripheral side upper surface of the lid body 17B.

  As shown in FIG. 9, a positioning pin 33 is engaged with the positioning hole 17E provided in the lid 17B of the heat insulating layer 17. The positioning pin 33 has a cylindrical shape, and a tapered portion is formed at the upper end to facilitate positioning work by engaging with the positioning holes of the needle holder 18 and the housing holder 19.

  Next, the needle holder 18 is laminated on the heat insulating layer 17 by engaging the positioning hole 34 with the positioning pin 33. As shown in FIG. 10, the needle holder 18 can accommodate a base portion 8A for connecting the plunger rod 8 of the needle 13 to the armature 10 with a small clearance (for example, 0.2 to 0.5 mm) around the periphery. A large number of recesses 35 having an inner diameter of various dimensions are arranged in a staggered manner. In the illustrated example, 253 recesses 35 are formed. The four through holes formed in the outermost periphery are positioning holes 34 to the positioning pins 33.

  Next, as shown in FIGS. 11 and 12, the base portion 8 </ b> A of the plunger rod 8 of the needle 13 is inserted into each recess 35 of the needle holder 18 and positioned with the valve body 7 facing upward. Then, as shown in FIGS. 13 and 14, the valve housing 5 with the nozzle plate 6 is placed on each of the standing needles 13. By bringing the valve seat 6B of the nozzle plate 6 into contact with the valve body 7 of each needle 13 to be in a seated state, the end of the large diameter side 5B of the valve housing 5 is slightly (from the edge of each recess 35 of the needle holder 18 ( For example, it floats and is mounted in 0.2-0.5 mm.

  15 and 16 show a cross-sectional view and a bottom view of the housing holder 19. The housing holder 19 includes a positioning hole 36 formed with four through holes on the outermost periphery, and a small gap (for example, 0.2 to 0.5 mm) between the large diameter portion 5B and the small diameter portion 5A of the valve housing 5. ) And the stepped through-hole 37 to be fitted in the same position and arrangement as the recess 35 of the needle holder 18. The depth of the large-diameter side hole 37B of the stepped through hole 37 is formed to be slightly larger than the axial dimension of the large-diameter portion 5B of the valve housing 5 (for example, about 0.3 to 0.5 mm). The axial dimension of the small diameter side hole 37 </ b> A is slightly shorter (for example, about 0.3 to 0.5 mm) than the axial dimension of the small diameter part 5 </ b> A of the valve housing 5.

  Next, as shown in FIGS. 17 and 18, the housing holder 19 is placed on the needle holder 18 in which the valve housing 5 with the nozzle plate 6 is inverted and combined for each plunger rod 8. The positioning pin 33 and the positioning hole 36 are engaged with each other with the large-diameter hole 37B of the lower side 37B facing down and the small-diameter hole 37A facing up. The large-diameter portion 5B of the valve housing 5 is slightly lifted from the upper surface of the needle holder 18, while contacting the stepped portion that is the bottom of the large-diameter hole 37B of the stepped through hole 37 of the housing holder 19. Positioning is restricted in the axial direction.

  Next, the heat insulating layer 17, the needle holder 18 and the housing holder 19 are fixed by fixing means (not shown), and the positioning pin 33 protruding upward is removed as shown in FIG. Is completed.

  FIG. 20 shows a state in which the positioning by the holding device 16 is completed. In the needle 13, the base 8A of the plunger rod 8 is brought into contact with the bottom of the recess 35 provided in the needle holder 18, and the valve body 7 at the tip is moved to the valve. It is seated on the valve seat 6B of the nozzle plate 6 integral with the housing 5 and is positioned and held in the axial direction. The large-diameter portion 5B of the valve housing 5 is slightly lifted from the upper surface of the needle holder 18, while being positioned in the axial direction by contacting the stepped surface of the stepped through hole 37 of the housing holder 19. ing. The end surface 6 </ b> C on the combustion chamber side of the nozzle plate 6 of the valve housing 5 is held in a state of slightly protruding from the surface of the housing support 19.

  In addition, a slight gap is formed between the inner surface of the stepped through hole 37 of the housing holder 19 and the outer peripheral surface of the valve housing 5. A slight gap is also formed between the outer peripheral surface of the base portion 8 </ b> A of the plunger rod 8 of the needle 13 and the inner peripheral surface of the recess 35 of the needle holder 18. These gaps are formed by selecting dimensions in order to improve the assembly workability of the valve housing 5 and the needle 13, improve stable holding performance, and absorb the amount of thermal expansion during heating.

  According to the holding device 16 assembled so as to hold the workpiece 3 in the above-described procedure, a combination component (work) of a large amount of the nozzle housing 5 and the needle 13 is arranged in an orderly and dense manner by the holding device 16. Can be prepared in units of lots, efficient transfer of workpieces between suppliers, is effective in shortening the time required for setting parts to the coating film processing equipment (plasma CVD equipment) and packing work, and improving mass production tact. In addition, it is possible to form a coating film on the surface of a large number of workpieces at a time, thereby reducing the manufacturing cost.

  The holding device 16 assembled by holding the workpiece by the procedure described above is installed on the cathode electrode 25 of the plasma CVD apparatus which is a film processing apparatus, and the film in the plasma CVD apparatus is obtained by the procedure shown in FIG. Execute the forming process.

  That is, as shown in the first step S1, the holding device 16 in which the workpiece 3 is set in the plasma CVD apparatus is set on the cathode electrode 25. Next, as shown in the second step S2, the air in the apparatus is discharged by the vacuum pump 31. Next, the temperature is raised as the film pretreatment operation in the third step S3. For this temperature increase, an inert argon gas is introduced into the apparatus, and a high-frequency electrode 1 is supplied to the high-frequency electrode 25 via a matching box from a high-frequency power source (frequency of about 13.56 [MHz], 300 [W]). Electric power is supplied to change the temperature of the workpiece 3 and the holding device 16 to a plasma state.

Next, as shown in the fourth step S4, a coating process is performed. In this coating treatment, for example, a mixed gas of methane gas (CH ₄ ) and 6 carbon fluoride 2 gas (C ₂ F ₆ ) is supplied into the apparatus, and the high frequency electrode 25 is supplied from the high frequency power supply 30 through the matching box 29. The second stage high frequency power (with a frequency of about 13.56 [MHz], 300 [W]) is supplied to the gas to form a plasma state, and the fuel formed on the nozzle plate 6 surface 6C and the nozzle plate 6 which are the workpiece surfaces A carbon film 15 in which fluorine atoms are taken in is formed on the inner surface of the injection hole 6 </ b> A and the tip surface of the valve body 7. Since a large number of the surfaces 6C of the nozzle plate 6 are arranged so as to slightly protrude from the surface of the housing holder 19, the plasma may be concentrated on the surface 6C of some of the nozzle plates 6 and discharged. Instead, each nozzle plate 6 surface 6C is uniformly coated 15.

  And in the stage which the said film processing was complete | finished, the process gas is discharged | emitted from inside the apparatus by 5th process S5, the holding | maintenance apparatus 16 holding the workpiece | work 3 which the process was complete | finished from the inside by 6th process S6 is taken out, By disassembling the holding device 16, it is possible to obtain a plurality of workpieces 3 that have been coated.

  As described above, since the combination parts (workpieces) of a large number of nozzle housings 5 and needles 13 are arranged in an orderly manner by the holding device 16, a coating can be formed on the surface of a large number of workpieces at a reduced cost, thereby reducing the manufacturing cost. Can be achieved.

  Further, since the holding device 16 having a structure for embedding the valve device 3 which is a part is used, the unevenness of the coating surface in the coating processing apparatus can be suppressed, and the unevenness caused by local concentrated discharge at the time of plasma discharge. The problem that the film thickness is not constant is solved, the film thickness is kept constant, and the quality is stabilized.

  Moreover, in the plasma CVD method, the temperature of the work 3 rises due to plasma discharge, but since the heat insulating layer 17 including a heat insulating material is disposed at the lower portion of the holding device 16, heat radiation from the lower portion of the holding device 16 is minimized. The heat escapes from the lower part and the workpiece 3 does not rise to the specified temperature and the coating adhesion is not deteriorated. The temperature of the workpiece 3 can be stably maintained at the specified temperature, and the coating adhesion Can be improved.

  Furthermore, the holding device 16 is accurately assembled by the positioning pins 33, and is positioned with high accuracy on the cathode electrode 25 by the positioning projections 17D of the heat insulating layer 17, so that the workpiece in the coating film processing apparatus can be obtained. By making the installation position highly accurate, the yield of the coating can be improved.

  Moreover, since the nozzle housing 6 welded part to which the nozzle plate 6 is welded and the needle 13 finished part are combined and held by the holding device 16, the nozzle plate 6 surface 6C and the surface in the fuel injection hole 6A In addition, a film can be formed on the tip surface of the valve body 7 of the needle 13 seated on the valve seat 6B, and adhesion of deposits to the tip surface of the valve body 7 can be suppressed, and the fuel injection amount can be reduced. The decrease can be further suppressed.

  A holding device 16A shown in FIG. 22 is a second embodiment of the holding device 16, and a heat-resistant silicone rubber, urethane rubber, or metal spring is provided at the bottom of each recess 35 that holds the plunger 8 base 8A of the needle holder 18. Only the configuration in which the elastic body 38 is accommodated is different from the holding device 16 of the first embodiment, and other configurations are the same as the holding device 16 of the first embodiment.

  In this holding device 16 </ b> A, the needle 13 is biased by the elastic body 38 from the base 8 </ b> A side, so that the valve body 7 at the tip is elastically contacted with the valve seat 6 </ b> B of the nozzle plate 6 of the valve housing 5. In addition, there is no backlash between the valve housing 5 and the needle 13 during transportation. Further, in the film processing by the plasma CVD method, the work 3 generates thermal expansion due to heat generated by plasma discharge, but the elastic thermal expansion can be absorbed by the elastic body 38. In addition, since a constant load can be applied uniformly to the nozzle housing 5 and the needle 13 by the elastic body 38, it is possible to eliminate the play of the work 3 during the covering operation and to eliminate uneven coating on the tip of the needle 13. .

  A holding device 16B shown in FIG. 23 is a third embodiment of the holding device 16, and the needle 13 is removed from the holding device 16 of the first embodiment so that only the valve housing 5 with the nozzle plate 6 is held. Is. In this embodiment, a large number of recesses 40 for accommodating the lower portion of the large diameter portion 5B of the valve housing 5 are formed on the upper surface of the intermediate holder 18A laminated on the heat insulating layer 17. Therefore, the large-diameter portion 5B is inserted into the recess 40 on the upper surface of the intermediate holder 18A, and a large number of valve housings 5 are aligned and arranged, and the positioning pins 33 and the positioning holes 36 are engaged with each other, so that these valve housings 5 are engaged. Next, the housing holder 19 is placed on the large diameter hole 37B of the stepped through hole 37 and the small diameter hole 37A is placed on top of each other. The axial dimension of the large-diameter hole 37B is shorter than the axial dimension of the housing holder 19 of the first and second embodiments, and the total dimension with the axial dimension of the recess 40 of the intermediate holder 18A is as follows. It is set to be equal to the axial dimension of the large diameter portion 5B. The valve housing 5 is positioned by being constrained in the axial direction by bringing the large diameter portion 5B into contact with the stepped portion which is the bottom of the large diameter hole 37B of the stepped through hole 37 of the housing holder 19.

  In this holding device 16B, only the valve housing 5 with the nozzle plate 6 is positioned and held. Therefore, as shown in FIG. 24, the coating is formed between the surface 6C on the combustion chamber side of the nozzle plate 6 and the injection holes 6A. Applied to the inner surface. Since the film formed by plasma CVD has high straightness of plasma discharge, the film does not go around and adhere to the valve seat 6B of the nozzle plate 6, and it is not necessary to polish the valve seat 6B of the nozzle plate 6 again.

  Also in this embodiment, since a large number of nozzle housings 5 (workpieces) are arranged in an orderly manner by the holding device 16B, a coating film can be formed on a large number of workpiece surfaces at the same time, and the manufacturing cost can be reduced.

  Further, since the holding device 16B having a structure for embedding the valve housing 5 which is a component is used, the unevenness of the coating surface in the coating processing apparatus can be suppressed, and the unevenness caused by the local concentrated discharge during the plasma discharge due to the unevenness. The problem that the film thickness is not constant is solved, the film thickness is kept constant, and the quality is stabilized.

  In addition, in the plasma CVD method, the temperature of the workpiece rises due to plasma discharge, but since the heat insulating layer 17 including a heat insulating material is disposed below the holding device 16B, heat radiation from the lower portion of the holding device 16B is minimized. The heat can escape from the lower portion and the workpiece does not rise to the specified temperature, so that the coating adhesion is not deteriorated, and the coating adhesion can be improved.

  Furthermore, the holding device 16B is assembled with the positioning pins 33 with high accuracy, and is positioned with high accuracy on the cathode electrode 25 with the positioning protrusions 17D of the heat insulating layer 17, so that the workpiece in the coating film processing apparatus can be obtained. By making the installation position highly accurate, the yield due to the coating can be improved.

  In the present embodiment, the following effects can be achieved.

  (A) The fuel injection valve 1 for an internal combustion engine in which a deposit prevention film is formed on the surface 6C of the nozzle plate 6 exposed to the combustion chamber of the valve device 3 and the inner surface of the injection hole 6A by a plasma CVD apparatus which is a film processing apparatus. A manufacturing apparatus and a manufacturing method, which can be disposed on the cathode electrode 25 of the coating processing apparatus, and can accommodate at least the nozzle plate 6 of the valve device 3 or the component 5 integrated with the nozzle plate 6 therein, A holding device 16 provided with a plurality of holding holes 35, 37 that are opened on the surface facing the anode electrode 23 of the plasma CVD apparatus is provided, and the fuel injection valve 1 is provided in the plurality of holding holes 35, 37 of the holding device 16. The surface 6C of the nozzle plate 6 exposed to the combustion chamber of the valve device 3 is moved from the opening surfaces of the plurality of holding holes 35 and 37 to the anode of the plasma CVD apparatus. Each of the plurality of valve devices 3 exposed to the electrodes 23 is positioned by the holding device 16 and the nozzle plate 6 of the plurality of valve devices 3 or the component 5 integrated with the nozzle plate 6 is positioned. The nozzle plate 6 or the component 5 integrated with the nozzle plate 6 and the holding device 16 are arranged on the cathode electrode 25 of the plasma CVD apparatus, and the surface 6C of the nozzle plate 6 facing the anode electrode 23 and the injection hole A film for preventing deposit adhesion is formed on the inner surface of 6A.

  Therefore, since a large amount of workpieces 3 are held by the holding device 16 with the nozzle plate 6 surface 6C and the injection hole 6A inner surface that require coating facing the anode electrode 23 in the plasma CVD apparatus, a coating is required. It is possible to coat the surface of the nozzle plate 6 surface 6C and the inner surface of the injection hole 6A all together, thereby reducing the cost. At the same time, since a large amount of the workpiece 3 is stably held without unevenness, the film thickness of the obtained film can be kept constant, and the film quality can be improved. In addition, since a large amount of work 3 is held by the holding device 16, if the work setting time and the work packing work are also performed with the holding device 16 in the plasma CVD apparatus, the time can be effectively shortened, and parts can be conveyed between suppliers. The mass production tact can be improved.

  (A) The holding device 16 includes a holding member 18 on the cathode electrode 25 side and a holding member 19 on the anode electrode side, and at least the nozzle plate 6 or the nozzle plate of the valve device 3 on the holding member 18 on the cathode electrode 25 side. The holding members 19 on the anode electrode 23 side are laminated in a state where the parts 5 integrated with the parts 6 are arranged, and these parts are positioned and held by the holding holes 37. That is, the holding device 16 includes a holding member 18 on the cathode electrode 25 side and a holding member 19 on the anode electrode 23 side, and at least the nozzle plate 6 or the nozzle plate of the valve device 3 on the cathode electrode 25 side holding member 18. 6 is arranged, and the holding member 19 on the anode electrode 23 side is arranged on the cathode electrode 25 side holding member 18 and the nozzle plate 6 in the arrangement state or the part 5 integrated with the nozzle plate 6. These parts are positioned and held by the holding holes 37. For this reason, only the part of the workpiece 3 where the coating is necessary is exposed and positioned from the holding device 16, and it is possible to prevent local concentration of plasma discharge due to unevenness between the workpiece surfaces in the plasma CVD apparatus. The unevenness between each other can be suppressed, the film thickness of the coating obtained on each workpiece 3 can be kept constant, and the coating quality can be improved.

  (C) The cathode electrode 25 side holding member 18 of the holding device 16 can be arranged such that the needles 13 are aligned with the holding holes 35 in the state where the valve element 7 faces the anode side electrode 23. The valve body 7 of the needle 13 is seated on the valve seat 6B, the nozzle plate 6 or the component 5 integrated with the nozzle plate 6 is arranged, and in this state, the anode electrode 23 side holding member 19 is laminated, These parts are positioned and held by the holding holes 37. That is, the needle 13 provided with the valve body 7 on the cathode electrode 25 side holding member 18 is aligned with the axial center of the holding hole 35 with the valve body 7 facing the anode side electrode 23, and the arranged needles 13 are arranged. The valve body 7 is seated on the valve seat 6B, the nozzle plate 6 or the parts 5 integrated with the nozzle plate 6 are arranged, and the anode electrode 23 side holding member 19 is stacked on the nozzle plate 6 to form the valve device The parts 3 are positioned and held by the holding holes 37.

  For this reason, since the needle 13 that has been subjected to grinding or the like is directly combined and coated without using a masking jig for protecting the valve seat 6B as in the prior art, the coating in the prior art simultaneously with the inner wall of the injection hole 6A. The local coating on the tip of the needle 13 (valve element 7), which has been difficult to construct, is also facilitated, and the reduction in the fuel injection amount of the internal combustion engine due to deposit adhesion on the tip of the needle 13 (valve element 7) can be further suppressed. In addition, since the needle 13 completed as a part is combined with the nozzle housing 5 completed as a part, it is not necessary to re-grind the valve seat 6B to improve the sealing degree, and the inner surface of the injection hole 6A is coated with polishing dust. No damage will occur.

  (D) As shown in FIG. 22, the cathode electrode 25 side holding member 18 of the holding device 6 </ b> A has elastic means 38 that urges the needle 13 having the valve body 7 to be seated on the valve seat 6 </ b> B of the nozzle plate 6. By being provided, the valve body 7 at the tip can be elastically brought into contact with the valve seat 6B of the nozzle plate 6 of the valve housing 5, and a backlash is generated between the valve housing 5 and the needle 13 during transportation or the like. There is no. Further, in the coating process by the plasma CVD method, the work 3 generates thermal elongation due to heat generated by plasma discharge, and this thermal elongation can be absorbed by the elastic body 38. In addition, since a constant load can be applied uniformly to the nozzle housing 5 and the needle 13 by the elastic body 38, it is possible to eliminate backlash of the work 3 during the covering operation, and to eliminate uneven coating on the tip of the needle 13.

  (E) Since the holding device 16 includes a heat insulating material (17) disposed between the cathode electrode 25 of the plasma CVD device, heat radiation from the lower portion of the holding device 16 can be suppressed to a minimum. Therefore, the heat does not escape and the workpiece 3 does not rise to the specified temperature, and the coating adhesion is not deteriorated, the temperature of the workpiece 3 can be stably maintained at the specified temperature, and the coating adhesion can be improved.

  (F) Although the quality of the coating varies depending on the position of the work 3 in the plasma CVD apparatus, the holding device 16 is positioned at the center of the cathode electrode 25 of the plasma CVD apparatus by positioning means 17D and 25A. Therefore, in combination with the assembly of the holding device 16 with the positioning pins 33 with high accuracy, the work placement position in the film processing apparatus can be made highly accurate, so that the coating yield can be improved. .

1 is a schematic cross-sectional view of a fuel injection valve to which a manufacturing apparatus and a manufacturing method according to an embodiment of the present invention are applied. The schematic sectional drawing which similarly shows the valve apparatus of a fuel injection valve. The principal part expanded sectional view of a valve apparatus. The principal part expanded sectional view which shows the example of a valve apparatus. Schematic explanatory drawing of the plasma CVD apparatus which is a manufacturing apparatus of a fuel injection valve. FIG. 6 is a layout layout of workpieces on the plasma CVD apparatus shown in FIG. 5. The perspective view of the holding | maintenance apparatus which is a manufacturing apparatus of the fuel injection valve of this embodiment. Sectional drawing of the heat insulation layer in a holding | maintenance apparatus. Sectional drawing of the workpiece holder of the holding | maintenance apparatus containing the heat insulation layer of FIG. The top view of a workpiece holder. Explanatory drawing which shows the arrangement | sequence state of the needle to the workpiece holder shown in FIG. The principal part enlarged view of FIG. Explanatory drawing which shows the mounting state of the valve housing to the holding | maintenance apparatus of FIG. The principal part enlarged view of FIG. Sectional drawing of a housing holder. The bottom view of a housing holder. Sectional drawing of the holding | maintenance apparatus of the state which laminated | stacked the housing holder. The principal part enlarged view of FIG. Sectional drawing of the assembled holding | maintenance apparatus. Sectional drawing which shows the workpiece | work holding state by a holding | maintenance apparatus. The process figure which shows the process process of the film by a plasma CVD apparatus. The principal part sectional view showing the 2nd example of a holding device. Sectional drawing of the principal part which shows 3rd Example of a holding | maintenance apparatus. Explanatory drawing which shows the film state to the workpiece | work by the holding | maintenance apparatus of 3rd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel injection valve 2 Housing 3 Valve apparatus 4 Solenoid apparatus 5 Valve housing 6 Nozzle plate 7 Valve body 8 Plunger rod 9 Overflow generator 10 Armature 11 Core 12 Coil 13 Needle 15 Coating 16 Holding apparatus 17 Thermal insulation layer 18 Needle holder 19 Housing holder

Claims (9)

An apparatus for manufacturing a fuel injection valve for an internal combustion engine, which forms a coating for preventing deposit adhesion on the surface of the nozzle plate exposed to the combustion chamber of the valve device and the inner surface of the injection hole by the coating processing device,
A plurality of holding holes that can be disposed on the cathode electrode of the film processing apparatus and open on the surface facing the anode electrode of the film processing apparatus, and are integrated with at least the nozzle plate or the nozzle plate of the valve device inside. The surface of the nozzle plate exposed to the combustion chamber of the valve device of the fuel injection valve is exposed from the opening surface of the plurality of holding holes so as to face the anode electrode of the film processing device. An apparatus for manufacturing a fuel injection valve, comprising a nozzle plate of a plurality of valve devices or a holding device capable of positioning a part integrated with the nozzle plate.   The holding device is composed of a cathode electrode side holding member and an anode electrode side holding member, and at least a nozzle plate of the valve device or a part integrated with the nozzle plate is arranged on the cathode electrode side holding member. 2. The fuel injection valve manufacturing apparatus according to claim 1, wherein a holding member on the anode electrode side is laminated in a state, and these components are positioned and held by a holding hole.   The cathode electrode side holding member of the holding device can be arranged in a state where the needle is aligned with the holding hole in a state where the valve body faces the anode side electrode, and each valve body of each needle is used as a valve seat. 3. The nozzle plate or a part integrated with the nozzle plate is arranged, and the anode electrode side holding member is laminated in that state, and these parts are positioned and held by the holding holes. A fuel injection valve manufacturing apparatus according to claim 1.   The fuel injection valve according to claim 3, wherein the cathode electrode side holding member of the holding device includes elastic means for urging the needle provided with the valve body to be seated on the valve seat of the nozzle plate. Manufacturing equipment.   The said holding | maintenance apparatus is equipped with the heat insulating material arrange | positioned between the cathode electrodes of the said film processing apparatus, The manufacturing apparatus of the fuel injection valve as described in any one of Claims 1-4 characterized by the above-mentioned.   6. The fuel injection valve manufacturing apparatus according to claim 1, wherein the holding device is positioned at a center of a cathode electrode of the film processing apparatus by positioning means. 7. . A method of manufacturing a fuel injection valve for an internal combustion engine, in which a coating for preventing deposit adhesion is formed on the surface of the nozzle plate exposed to the combustion chamber of the valve device and the inner surface of the injection hole by the coating processing device,
A plurality of holding holes that can be disposed on the cathode electrode of the film processing apparatus and open on the surface facing the anode electrode of the film processing apparatus, and are integrated with at least the nozzle plate or the nozzle plate of the valve device inside. A holding device that can accommodate
The surface of the nozzle plate exposed to the combustion chamber of the valve device of the fuel injection valve is exposed to the plurality of holding holes of the holding device so as to face the anode electrode of the film processing apparatus from the opening surface of the plurality of holding holes, respectively. And positioning the nozzle plate of a plurality of valve devices or parts integrated with the nozzle plate to the holding device,
The nozzle plate of the plurality of positioned valve devices or a component integrated with the nozzle plate and the holding device thereof are arranged on the cathode electrode of the coating apparatus, and the surface of the nozzle plate facing the anode electrode, the tip of the needle A method of manufacturing a fuel injection valve, comprising forming a deposit-preventing coating on a surface and an inner surface of an injection hole. The holding device includes a cathode electrode side holding member and an anode electrode side holding member,
Arranging at least the nozzle plate of the valve device or a part integrated with the nozzle plate on the cathode electrode side holding member,
The anode electrode side holding member is laminated on the cathode electrode side holding member and the nozzle plate in the arrangement state or the parts integrated with the nozzle plate, and these parts are positioned and held by holding holes. A method for manufacturing the fuel injection valve according to claim 7. The cathode electrode side holding member of the holding device can be arranged with the needle aligned with the holding hole in the state where the valve body faces the anode side electrode,
A needle provided with a valve body on the cathode electrode side holding member is arranged with its axis aligned with the holding hole in a state where the valve body faces the anode side electrode,
The valve body of the arranged needles is seated on the valve seat and the nozzle plate or the parts integrated with the nozzle plate are arranged,
9. The method for manufacturing a fuel injection valve according to claim 8, wherein the anode electrode side holding member is laminated from above, and the components of the valve device are positioned and held by the holding holes.