JP4897728B2 - Electromagnetic fuel injection valve - Google Patents

Description

  The present invention relates to an electromagnetic fuel injection valve mainly used for a fuel supply system of an internal combustion engine, and more particularly to a valve body cooperating with the valve seat in a valve housing having a valve seat at a front end, and the valve body. A valve assembly consisting of a movable core coupled to the valve housing is accommodated, and a fixed core is provided at the rear end of the valve housing to attract the movable core and open the valve body when excited, and is fixed from these valve housings. A coil assembly consisting of a bobbin and a coil wound around the bobbin and energizing the fixed core when energized is disposed around the core, and a power supply connected to the coil is provided on one side of the coil assembly. The present invention relates to an improvement in an electromagnetic fuel injection valve in which a coupler for holding a terminal is disposed and a coil housing that magnetically connects between a valve housing and a fixed core is disposed on the outer periphery of a coil assembly.

Such an electromagnetic fuel injection valve is known as disclosed in Patent Document 1, for example.
JP 2005-240731 A

  Conventionally, in such an electromagnetic fuel injection valve, the valve housing, coil assembly, and fixed core have been used in order to obtain quietness by shutting off the operating noise generated when the valve body is opened and closed in the valve housing. It is known to form a sound insulating resin layer on the outer periphery.

  By the way, in the conventional one, when molding the above sound insulation resin layer, the material resin penetrates into the coil housing and wraps the coil assembly to increase the strength of the coil assembly. The coil housing is provided with a plurality of cutouts that promote the penetration of the resin. However, it is necessary to provide a large cutout in the plurality of coil housings in order to accurately penetrate the coil assembly. However, these notches are not preferable in terms of magnetic characteristics of the electromagnetic fuel injection valve because the cross-sectional area of the magnetic path in the coil housing is reduced.

  The present invention has been made in view of such circumstances, and can prevent the reduction of the magnetic path cross-sectional area of the coil housing while increasing the strength of the coil assembly and is excellent in sound insulation. The purpose is to provide a valve.

  To achieve the above object, the present invention provides a valve assembly comprising a valve body cooperating with the valve seat and a movable core coupled to the valve body in a valve housing having a valve seat at a front end. A fixed core is installed at the rear end of the valve housing to suck the movable core and open the valve body when excited. The fixed core extends from the valve housing to the fixed core, and there is a bobbin, A coil assembly comprising a coil wound around a bobbin and exciting a fixed core when energized is disposed, and a coupler for holding a power supply terminal connected to the coil is disposed on one side of the coil assembly. In an electromagnetic fuel injection valve in which a coil housing that magnetically connects between a valve housing and a fixed core is disposed on the outer periphery of a solid body, a first sound insulation resin layer is formed on the outer periphery of the coil assembly, and the first sound insulation resin is formed. Integrated resin layer and coupler A coil assembly with a coupler is formed by molding, and the bobbin of the coil assembly with a coupler is fitted to the outer peripheral surfaces of the valve housing and the fixed core, and an air layer for sound insulation is formed between the fitting peripheral surfaces. Then, the coil housing for accommodating the coil assembly with the coupler is fitted and fixed to the valve housing and the fixed core, and the second sound insulation resin layer is formed so as to cover the outer periphery of the valve housing and the outer periphery of the base of the coupler. This is the first feature.

  According to the present invention, in addition to the first feature, the valve housing includes a body portion that covers the outer peripheral surface side of the coil assembly, an annular end wall portion that is bent radially inward from a front end portion of the body portion, A boss portion that protrudes axially forward from the inner peripheral end of the annular end wall portion and is fitted and fixed to the valve housing, and cooperates with the annular end wall portion to clamp the bobbin from the axial direction. In addition, a second feature is that a flange-like yoke fitted and fixed to the body portion is formed integrally with the fixed core.

  Furthermore, in addition to the second feature of the present invention, a third feature is that a plurality of compressively deformable protrusions that contact the annular end wall portion or the yoke are formed on at least one axial end surface of the synthetic resin bobbin. It is characterized by.

  Furthermore, in addition to the first feature, the present invention provides a vertical hole communicating with the inside of the valve housing at the center of the fixed core, and the yoke has an outer diameter larger than that of the fixed core. A fourth feature is that the fuel inlet cylinder for guiding the fuel is integrally provided.

  According to the first aspect of the present invention, the first sound insulation resin layer is formed on the outer periphery of the coil assembly, and the first sound insulation resin layer and the coupler are integrally formed to constitute a coil assembly with a coupler. The bobbin of the coil assembly with the coupler is fitted to the outer peripheral surfaces of the valve housing and the fixed core, and an air layer for sound insulation is formed between the fitting peripheral surfaces to accommodate the coil assembly with the coupler. The coil housing is fitted and fixed to the valve housing and the fixed core, and the second sound insulation resin layer is formed so as to cover the outer periphery of the valve housing and the outer periphery of the base of the coupler. It is not necessary to provide a notch that penetrates the resin layer, and the reduction in the magnetic path cross-sectional area of the coil housing can be suppressed, which can contribute to the improvement of the magnetic characteristics of the electromagnetic fuel injection valve. In addition, when the second sound insulation resin layer is molded, even if it is necessary to provide a notch or through hole for resin penetration in the body of the coil housing in order to partially fuse it with the first sound insulation resin layer, the cut The notches or through-holes need only be small enough not to affect the cross-sectional area of the magnetic path of the coil housing.

  In addition, the sound insulation air layer provided between the valve housing and the fixed core and the coil assembly surrounding the valve housing and the coil assembly greatly reduces the contact area between the valve housing and the fixed core and the coil assembly. Can be effectively suppressed from being transmitted to the coil assembly. Moreover, since the first sound insulation resin layer made of hard synthetic resin formed integrally with the coupler is formed on the outer periphery of the coil assembly, even if there is vibration sound transmitted to the coil assembly, Can be absorbed by the first sound insulation resin layer, so that the generation of resonance noise from the coupler can be prevented. Further, a coil housing that is fitted and fixed to the valve housing and the fixed core is disposed on the outer periphery of the first sound insulation resin layer, and the coil housing, the base of the coupler, and the outer periphery of the fuel inlet cylinder are wrapped around the second. Since the sound insulation resin layer is formed, even if there is vibration sound that has passed through the first sound insulation resin layer, it can be insulated by the coil housing and the second sound insulation resin layer, and the coil housing and the fuel inlet cylinder Therefore, it is possible to provide a quieter electromagnetic fuel injection valve.

  Further, when manufacturing an electromagnetic fuel injection valve, a coil assembly with a coupler manufactured in advance is fitted to the outer periphery of the valve housing and the fixed core, and then the coil housing containing the coil assembly is fitted to the magnetic cylinder and the yoke. The coil assembly with the coupler can be fixed simultaneously with the installation of the coil housing, the assembly is simple, and the coil assembly with the coupler is fixed to the valve housing and the fixed core. Thus, the next second sound insulation resin layer can be easily molded, and the electromagnetic fuel injection valve can be efficiently manufactured as a whole.

  According to the second aspect of the present invention, the coil assembly can be easily and accurately supported by the coil housing and the yoke.

  According to the third feature of the present invention, the bobbin can be securely held by the coil housing and the yoke without play due to the compressive deformation of the protrusion.

  According to the fourth feature of the present invention, the fuel inlet cylinder connected to the flange-shaped yoke of the fixed core has a larger diameter than that of the fixed core, so that the fuel inlet cylinder contributes to strengthening the rigidity of the fixed core. The vibration of the fixed core due to the vibration sound can be suppressed.

  Embodiments of the present invention will be described below on the basis of preferred embodiments of the present invention shown in the accompanying drawings.

  1 is a longitudinal sectional view of an electromagnetic fuel injection valve for an internal combustion engine according to a first embodiment of the present invention, FIG. 2 is an enlarged view of part 2 of FIG. 1, and FIG. 3 is a coil assembly with a coupler in the electromagnetic fuel injection valve. FIG. 4 is a sectional view corresponding to FIG. 2, showing a second embodiment of the invention.

  First, the description starts with the description of the first embodiment of the present invention shown in FIGS.

  1 and 2, a valve housing 1 of an electromagnetic fuel injection valve I for an internal combustion engine includes a cylindrical valve seat member 2 and a magnetic cylindrical body 4 that is coaxially coupled to a rear end portion of the valve seat member 2. And a non-magnetic cylinder 6 coaxially coupled to the rear end of the magnetic cylinder 4.

  The rear half 2b of the valve seat member 2 is press-fitted into the inner peripheral surface of the front end portion of the magnetic cylindrical body 4, and is liquid-tightly coupled by laser beam welding. The press-fitting and laser beam welding will be described later. Further, the magnetic cylindrical body 4 and the nonmagnetic cylindrical body 6 are connected to each other coaxially and liquid-tightly by laser beam welding over the entire circumference with the opposed end faces butted.

  The valve seat member 2 includes a valve hole 7 that opens to a front end surface thereof, a conical valve seat 8 that is continuous with the inner end of the valve hole 7, and a cylindrical guide hole 9 that is continuous with a large diameter portion of the valve seat 8. And. A steel plate injector plate 10 having a plurality of fuel injection holes 11 communicating with the valve hole 7 is welded to the front end surface of the valve seat member 2 in a liquid-tight manner.

  A cylindrical fixed core 5 is liquid-tightly pressed and fixed to the inner peripheral surface of the nonmagnetic cylindrical body 6 from the rear end side. At this time, a portion that does not fit with the fixed core 5 remains at the front end portion of the nonmagnetic cylindrical body 6, and the valve assembly V is accommodated in the valve housing 1 that extends from the portion to the valve seat member 2.

  The valve assembly V includes a hemispherical valve portion 16 that opens and closes the valve hole 7 in cooperation with the valve seat 8 and a valve rod portion 17 that supports the valve body 18 and a rear end of the valve rod portion 17. The valve rod portion 17 is fitted to the end wall portion 13a of the connection hole 13 until the end portion 13a abuts the end wall portion 13a. The valve rod portion 17 and the movable core 12 are fixed to each other by welding.

  The movable core 12 extends from the magnetic cylindrical body 4 to the nonmagnetic cylindrical body 6, is inserted into them, and is coaxially opposed to the fixed core 5. The valve rod portion 17 is formed to have a smaller diameter than the guide hole 9, and the journal portion 17 a that protrudes radially outward at the outer periphery thereof and is slidably supported on the inner peripheral surface of the guide hole 9. Are integrally formed, and the journal portion 17a is provided with a plurality of notches communicating between the front and rear.

  The valve assembly V includes a vertical hole 19 that starts from the rear end surface of the movable core 12 and ends before the valve portion 16, and the vertical hole 19 is provided on the outer peripheral surface of the valve flange portion 17 between the first journal portion 17 a and the valve portion 16. And a lateral hole 20 is provided. An annular spring seat 24 facing the fixed core 5 is formed in the middle of the vertical hole 19 in the movable core 12.

  A flange-shaped yoke 5y protruding from the outer peripheral surface of the fixed core 5 and a fuel inlet cylinder 26 having a larger diameter than the fixed core 5 extending rearward in the axial direction are integrally formed from the yoke 5y. It will be installed continuously. The fixed core 5 and the fuel inlet cylinder 26 are provided with a series of vertical holes 21 communicating with the vertical holes 19 of the movable core 12. The diameter of the vertical holes 21 is increased on the inlet side of the fuel inlet cylinder 26. A fuel filter 27 is attached to the portion 21a.

  A pipe-like retainer 23 with a slit is fixed by being elastically fitted to the inner peripheral surface of the intermediate portion of the vertical hole 21, and the movable core 12 is attached to the valve body 18 between the retainer 23 and the spring seat 24. The valve spring 22 that biases the valve closing side is contracted. At that time, the set load of the valve spring 22 is adjusted by adjusting the fitting depth of the retainer 23 into the vertical hole 21.

  In FIG. 1 and FIG. 2, the opposite end surfaces of the fixed core 5 and the movable core 12 are referred to as a fixed suction surface 35 and a movable suction surface 36, and the fixed core 5 has the fixed suction surface 35. A small-diameter portion 5a, and a main portion 5b having a diameter larger than that of the small-diameter portion 5a. The main-diameter portion 5b is coaxially connected to the small-diameter portion 5a via an annular step portion 5c. The latter half of the nonmagnetic cylindrical body 6 is press-fitted into the small diameter portion 5a so that the inner peripheral surface of the nonmagnetic cylindrical body 6 is in close contact, and the rear end surface of the small diameter portion 5a is abutted against the annular step portion 5c.

  On the other hand, the movable core 12 is formed with substantially the same diameter as the small diameter portion 5 a of the fixed core 5. The movable core 12 is embedded with a non-magnetic stopper collar 28 that penetrates the vertical hole 19 and slightly protrudes from the movable suction surface 36, and the stopper collar 28 is fixed to the fixed core 5. The operating limit of the movable core 12 is defined by abutting on 35.

  In order to adjust the gap generated between the stationary suction surface 35 and the stopper collar 28 to a predetermined value when the valve element 18 is opened, in other words, when the valve element 18 is closed, the inner circumference of the magnetic cylinder 4 is adjusted. The press-fitting depth of the valve seat member 2 with respect to the surface is adjusted. After the adjustment, the entire boundary corner between the front end surface of the magnetic cylindrical body 4 and the outer peripheral surface of the valve seat member 2 is welded by irradiating the laser beam B from the laser torch 40 obliquely from the front, Ensures adherence and ensures liquid tightness. By the way, the valve seat member 2 is formed of a material having a hardness higher than that of the magnetic cylinder 4 due to its nature. In this case, the irradiation point of the laser beam B is set to the position of the valve seat member 2 and the magnetic cylinder 4. If welding is performed by offsetting from the boundary to the magnetic cylinder 4 side, direct heat input of the laser beam B to the high hardness valve seat member 2 can be avoided and occurrence of weld cracks in the valve seat member 2 can be prevented.

  The front half 2a of the valve seat member 2 is thicker and larger in diameter than the rear half 2b press-fitted into the magnetic cylindrical body 4 in order to increase the rigidity around the valve seat 8, and the front half 2a and the latter half Between the 2b, a tapered step portion 2c that is reduced in diameter toward the rear is formed. The tapered step portion 2c does not hinder the irradiation of the laser beam B from the laser torch 40 to the welded portion.

  As shown in FIGS. 2 and 3, a coil assembly 30 is disposed on the outer periphery of the magnetic cylinder 4 from the fixed core 5 to the fixed core 5. The coil assembly 30 includes a bobbin 31 fitted over the outer periphery of the magnetic cylindrical body 4 from the fixed core 5 and a coil 32 wound around the bobbin 31. A support arm 33 is integrally formed so as to project in the radial direction and support the power supply terminal 34 connected to the coil 32.

  A first sound insulation resin layer 41 made of a hard synthetic resin containing glass fiber is formed on the outer periphery of the coil assembly 30, and protrudes to one side of the first sound insulation resin layer 41 and the coil assembly 30. The coil assembly 30 with the coupler 42 is configured by integrally forming the coupler 42 that is arranged in this manner and that holds the power supply terminal 34.

  Between the inner peripheral surface of the bobbin 31 of the coil assembly 30 with the coupler 42 and those outer peripheral surfaces extending from the rear end portion of the magnetic cylindrical body 4 to the fixed core 5, a cylindrical sound insulating air layer 43 is formed. Defined. In order to define the air layer 43, an annular groove 44 having a depth corresponding to the thickness of the air layer 43 is formed on the outer peripheral surface from the rear end portion of the magnetic cylinder 4 to the fixed core 5. The annular groove 44 can be easily formed by cutting.

  The coil assembly 30 with the coupler 42 is housed in a magnetic coil housing 45 and is sandwiched in the axial direction by the annular end wall 45b of the coil housing 45 and the yoke 5y on the outer periphery of the fixed core 5. The Specifically, the coil housing 45 covers the outer end surface of the coil assembly 30 and the front end surface of the bobbin 31 of the coil assembly 30 by bending inward in the radial direction from the front end of the body 45a. An annular end wall portion 45b and a cylindrical boss portion 45c projecting forward from the front end of the annular end wall portion 45b are formed. The boss portion 45c is press-fitted into the outer peripheral surface of the magnetic cylindrical body 4, and simultaneously the body portion 45a. Is press-fitted into the outer peripheral surface of the yoke 5y. Thus, the coil housing 45 is attached, and the bobbin 31 of the coil assembly 30 with the coupler 42 is sandwiched between the annular end wall 45b and the yoke 5y. At this time, a plurality of protrusions 47 are formed on at least one of the front end face and the rear end face of the bobbin 31, and these protrusions 47 are compressed and deformed by the pressure from the contact member 45b or 5y.

  A notch 48 for receiving the base of the coupler 42 is provided at the rear end of the body 45 a of the coil housing 45.

  After the coil housing 45 is attached, a second sound insulation resin layer 49 is formed from the coil housing 45 to the root of the coupler 42 and the middle of the fuel inlet cylinder 26 to cover the outer peripheral surface thereof. The second sound insulation resin layer 49 is made of a soft synthetic resin such as thermoplastic polyester elastomer.

  Next, the operation of the first embodiment will be described.

  When the coil 32 is demagnetized, the valve assembly V is pressed forward by the urging force of the valve spring 22, and the valve body 18 is seated on the valve seat 8. Therefore, the fuel pressure-fed from the fuel pump (not shown) to the fuel inlet cylinder 26 is kept in the valve housing 1 through the pipe-like retainer 23, the vertical hole 19 and the horizontal hole 20 of the valve assembly V.

  When the coil 32 is energized by energization, a magnetic flux generated by the coil 32 sequentially travels through the coil housing 45, the magnetic cylindrical body 4, the movable core 12, and the fixed core 5, and is generated between the movable suction surface 36 and the fixed suction surface 35. The movable core 12 is attracted to the fixed core 5 against the set load of the valve spring 22 by the attraction force due to the magnetic force, and the valve body 18 is separated from the valve seat 8, so that the valve hole 7 is opened and the valve seat member 2 is opened. The internal high-pressure fuel leaves the valve hole 7 and is injected from the fuel injection hole 11 of the injector plate 10 toward the intake valve of the engine.

  At this time, the stopper collar 28 embedded in the movable core 12 abuts against the stationary suction surface 35 of the stationary core 5, so that the valve opening limit of the valve body 18 is defined, and the movable suction surface 36 and the stationary side are fixed. A predetermined air gap remains between the suction acting surface 35. Therefore, direct contact between the movable suction surface 36 and the fixed suction surface 35 is avoided. Moreover, since the stopper collar 28 is non-magnetic, when the coil 32 is demagnetized, the residual magnetism between the cores 5 and 12 can be quickly lost, and the valve closing response of the valve body 18 can be improved.

  A vibration sound is generated by the contact of the stopper collar 28 with the fixed core 5 and the seating of the valve body 18 on the valve seat 8 as described above, and this is transmitted to the coupler 42 via the valve housing 1 and the fixed core 5. Then, although resonance noise is generated from the coupler 42, in the present invention, the sound insulation air layer 43 provided between the valve housing 1 and the fixed core 5 and the coil assembly 30 surrounding the valve housing 1 is provided with a valve. The contact area between the housing 1 and the fixed core 5 and the coil assembly 30 is greatly reduced, and transmission of the vibration sound to the coil assembly 30 is effectively suppressed. In addition, since the first sound insulation resin layer 41 made of hard synthetic resin and formed integrally with the coupler 42 is formed on the outer periphery of the coil assembly 30, there is vibration noise transmitted to the coil assembly 30. However, since it can be absorbed by the first sound insulation resin layer 41, the generation of resonance noise from the coupler 42 can be prevented. Further, since the first sound insulation resin layer 41 integrally formed with the coupler 42 is made of a hard synthetic resin containing glass fiber, the coupler 42 can be provided with sufficient rigidity.

  Further, a coil housing 45 fitted and connected to the valve housing 1 and the yoke 5y is disposed on the outer periphery of the first sound insulation resin layer 41. The coil housing 45, the root of the coupler 42, and the outer periphery of the fuel inlet cylinder 26 are wrapped around. Since the second sound insulation resin layer 49 is formed so as to be embedded, even if there is a vibration sound that has passed through the first sound insulation resin layer 41, the sound is insulated by the coil housing 45 and the second sound insulation resin layer 49. And the generation of radiated sound from the coil housing 45 and the fuel inlet cylinder 26 can be suppressed. Further, since the second sound insulating resin layer 49 is made of a soft synthetic resin, it can also function as a protective layer that protects the electromagnetic fuel injection valve I by absorbing an impact at the time of contact with another object.

  In manufacturing the electromagnetic fuel injection valve I, the coil assembly 30 with the coupler 42 manufactured in advance is fitted to the outer periphery of the valve housing 1 and the fixed core 5, and then the coil housing 45 that houses the coil assembly 30 is magnetized. Since the bobbin 31 of the coil assembly 30 is fitted in the cylindrical body 4 and the yoke 5y and is clamped between the annular end wall 45b of the coil housing 45 and the yoke 5y in the axial direction, The coil assembly 30 with the coupler 42 can be fixed, and the assembly is simple. In addition, the coil assembly 30 with the coupler 42 is fixed to the valve housing 1 and the fixed core 5, so that The sound insulation resin layer 49 can be easily molded, and the electromagnetic fuel injection valve I can be efficiently manufactured as a whole.

  At this time, a plurality of projections 47 are formed on at least one of the front end surface and the rear end surface of the bobbin 31 of the coil assembly 30, and these projections 47 are compressed and deformed by contact pressure with the annular end wall portion 45 b or the yoke 5 y. Therefore, the bobbin 31 can be accurately sandwiched between the annular end wall 45b and the yoke 5y without play.

  In addition, the body 45a of the coil housing 45 disposed on the outer periphery of the first sound insulation resin layer 41 has a notch that allows the first sound insulation resin layer 41 to penetrate, except for one notch 48 that receives the root of the coupler 42. Since there is no need to provide the coil housing 45, the reduction in the magnetic path cross-sectional area of the coil housing 45 can be minimized, and the magnetic characteristics of the electromagnetic fuel injection valve I can be improved. In addition, when the first sound insulation resin layer 41 is molded, the second sound insulation resin layer 49 is partially cut into the body 45a of the coil housing 45 in order to fuse it with the first sound insulation resin layer 41. Even when it is necessary to provide a through hole, the notch or the through hole may be small enough that it hardly affects the cross-sectional area of the magnetic path of the coil housing 45.

  Further, the fuel inlet cylinder 26 integrally connected to the rear side in the axial direction from the flange-shaped yoke 5y of the fixed core 5 is formed to have a larger diameter than the fixed core 5, thereby contributing to the rigidity enhancement of the fixed core 5. The vibration of the fixed core 5 due to the vibration sound can be suppressed.

  Next, a second embodiment of the present invention shown in FIG. 4 will be described. In the second embodiment, an annular groove 44 ′ is formed on the inner peripheral surface of the bobbin 31 in order to form an air layer 43 between the bobbin 31 and the outer peripheral surface extending from the magnetic cylindrical body 4 to the fixed core 5. Except for this point, the configuration is the same as that of the previous embodiment. Therefore, in FIG. 4, the same reference numerals are assigned to portions corresponding to those of the previous embodiment, and redundant description is omitted.

  According to the second embodiment, since the annular groove 44 ′ can be formed when the synthetic resin bobbin 31 is molded, the air layer 43 can be easily formed.

  As mentioned above, although the Example of this invention was described, this invention is not limited to it, A various design change is possible in the range which does not deviate from the summary. For example, in forming the air layer 43, both the annular groove 44 on the fixed core 5 side in the first embodiment and the annular groove 44 ′ on the bobbin 31 side in the second embodiment can be employed.

1 is a longitudinal sectional view of an electromagnetic fuel injection valve for an internal combustion engine according to a first embodiment of the present invention. FIG. 2 is an enlarged view of part 2 of FIG. 1. The longitudinal cross-sectional view of the coil assembly with a coupler alone in the said electromagnetic fuel injection valve. Sectional drawing corresponding to FIG. 2 which shows 2nd Example of invention.

Explanation of symbols

I ... Electromagnetic fuel injection valve V ... Valve assembly 1 ... Valve housing 5 ... Fixed core 8 ... Valve seat 12 ... Movable Core 18 ... Valve 21 ... Vertical hole 26 ... Fuel inlet cylinder 30 ... Coil assembly 31 ... Bobbin 32 ... Coil 34 ... Power supply terminal 41 ··· First sound insulating resin layer 42 ··· Coupler 43 ··· Air layer 45 ··· Coil housing 45a · · · Body 45b · · · End wall portion 45c · · · Boss 47 ... projection 49 ... second sound insulation resin layer

Claims (4)

In a valve housing (1) having a valve seat (8) at the front end, a valve body (18) cooperating with the valve seat (8) and a movable core (12) coupled to the valve body (18) A fixed core (5) that accommodates the valve assembly (V) and opens the valve body (18) by sucking the movable core (12) when excited at the rear end of the valve housing (1). A coil which is provided in series and extends from the valve housing (1) to the fixed core (5) and is wound around the bobbin (31) and the bobbin (31) to excite the fixed core (5) when energized. A coil assembly (30) comprising (32) is disposed, and a coupler (42) for holding a power supply terminal (34) connected to the coil (32) is disposed on one side of the coil assembly (30). And magnetically connecting the valve housing (1) and the fixed core (5) to the outer periphery of the coil assembly (30). The electromagnetic fuel injection valve which is disposed a coil housing (45) that,
The first sound insulation resin layer (41) is formed on the outer periphery of the coil assembly (30), and the first sound insulation resin layer (41) and the coupler (42) are integrally formed to form a coil assembly with the coupler (42). A solid body (30) is constructed, and the bobbin (31) of the coil assembly (30) with the coupler (42) is fitted to the outer peripheral surfaces of the valve housing (1) and the fixed core (5), and these fittings A sound insulation air layer (43) is formed between the peripheral surfaces, and a coil housing (45) for accommodating the coil assembly (30) with the coupler (42) is fitted into the valve housing (1) and the fixed core (5). An electromagnetic fuel injection valve characterized in that a second sound insulation resin layer (49) is formed so as to cover the outer periphery of the valve housing and the base outer periphery of the coupler (42). The electromagnetic fuel injection valve according to claim 1,
The valve housing (1) includes a body part (45a) that covers the outer peripheral surface side of the coil assembly (30), and an annular end wall part (45b) that bends radially inward from the front end part of the body part (45a). And a boss portion (45c) that protrudes forward in the axial direction from the inner peripheral end of the annular end wall portion (45b) and is fitted and fixed to the valve housing (1), and the annular end wall portion (45b) In order to clamp the bobbin (31) from the axial direction, a flange-like yoke (5y) fitted and fixed to the body (45a) is formed integrally with the fixed core (5). An electromagnetic fuel injection valve characterized by that. The electromagnetic fuel injection valve according to claim 2,
A plurality of compression-deformable projections (47) contacting the annular end wall (45b) or the yoke (5y) are formed on at least one axial end surface of the synthetic resin bobbin (31). Electromagnetic fuel injection valve. The electromagnetic fuel injection valve according to claim 1,
A vertical hole (21) communicating with the inside of the valve housing (1) is provided at the center of the fixed core (5), and the yoke (5y) has an outer diameter larger than that of the fixed core (5) and the vertical hole. An electromagnetic fuel injection valve characterized in that a fuel inlet cylinder (26) for guiding fuel is integrally connected to (21).

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