JP2024039313A - electromagnetic fuel injection valve - Google Patents

Abstract

[Problem] In an electromagnetic fuel injection valve, when the movable core is in a floating state, even if the pressing force of the auxiliary spring against the movable core fluctuates in various parts, the moment generated in the movable core is suppressed to prevent the movable core from tilting. do it like this. A movable core 41 is provided with an annular recess 51 that is open at the rear end surface and whose bottom surface 51a is located closer to the front end surface of the movable core 41 than the center of gravity G of the movable core 41. A spring 55 is accommodated, and the front end of the auxiliary spring 55 is supported on the bottom surface 51a. [Selection diagram] Figure 2

Description

The present invention relates to an electromagnetic fuel injection valve mainly used in a fuel supply system of an internal combustion engine, and in particular, to a valve housing having a valve seat at the front end, and a hollow fixed core connected to the rear end of the valve housing. a coil disposed around the outer periphery of the fixed core; a valve element having a rod connected to a valve portion that cooperates with the valve seat; a movable core that is slidably disposed in the hollow part of the fixed core and has a through hole in the center that is penetrated by the rod; When the coil is energized, the valve-opening side stopper is pushed by the movable core attracted by the fixed core to open the valve body, and the valve-closing stopper is disposed opposite to the front end surface of the movable core. a side stopper, a valve spring that biases the valve body in a valve closing direction, and a valve spring that moves the movable core away from the valve opening side stopper to allow the valve body to close when the coil is not energized. The present invention relates to an improvement in an electromagnetic fuel injection valve including an auxiliary spring that urges the valve-closing stopper to come into contact with the valve-closing stopper.

Such an electromagnetic fuel injection valve is already known as disclosed in Patent Document 1 below.

Patent No. 6788085

In the electromagnetic fuel injection valve described in Patent Document 1, when the auxiliary spring that biases the movable core in the direction of contact with the valve-closing side stopper is compressed between the movable core and the valve-opening side stopper, the main part of the auxiliary spring is The auxiliary spring is fitted onto the outer periphery of the shaft of the stopper on the opening side, and the front end of the auxiliary spring is supported in a shallow counterbore on the rear end surface of the movable core to position the auxiliary spring and prevent it from buckling. ing.

However, there is some play in the radial direction between the auxiliary spring and the shaft of the valve opening side stopper, and between the auxiliary spring and the counterbore, and this play causes lateral vibration in the auxiliary spring when the movable core operates. let When the auxiliary spring oscillates laterally, the pressing force of the auxiliary spring against the rear end of the movable core varies at each part, which generates a moment in the movable core.

Incidentally, in the device described in Patent Document 1, as shown in FIG. When the auxiliary spring 55 is in a floating state where it does not come into contact with either the valve-opening side stopper 48 or the valve-closing side stopper 49, for example, the pressing force of the auxiliary spring 55 against the movable core 41 on the left and right sides is different from F1>F2 due to the lateral vibration of the auxiliary spring 55. When this occurs, a moment M around the center of gravity G is generated in the movable core 41, causing the movable core 41 to tilt. Moreover, since the moment M increases as the movable core 41 tilts, it promotes the tilt of the movable core 41.

Therefore, when the movable core is attracted to the fixed core in a tilted state, there is a delay in proper adsorption to the fixed core, which delays opening of the valve body. Furthermore, if the movable core contacts the valve-closing stopper in an inclined state, the movable core may unevenly contact the valve-closing stopper, causing problems such as bouncing.

The present invention has been made in view of such circumstances, and when the movable core is in a floating state where it does not come into contact with either the valve-opening side stopper or the valve-closing side stopper, the pressing force of the auxiliary spring against the movable core varies at each part. The electromagnetic core also prevents the movable core from tilting by suppressing the moment generated in the movable core, improving the responsiveness of the movable core when the coil is energized, and suppressing the bouncing of the movable core when the coil is energized. The purpose of this invention is to provide a type fuel injection valve.

In order to achieve the above object, the present invention provides a valve housing having a valve seat at the front end, a hollow fixed core connected to the rear end of the valve housing, and a hollow fixed core arranged around the outer periphery of the fixed core. A coil, a valve element having a rod connected to a valve part that cooperates with the valve seat, and a valve body that is slidably disposed within the valve housing while facing the front end surface of the fixed core, and is located in the center of the valve body. is fixed to the rod and is slidably disposed in a hollow part of the fixed core, and is attracted to the fixed core when the coil is energized. a valve-opening stopper that is pushed by the movable core to open the valve body; and an annular valve-closing stopper that protrudes from the inner peripheral surface of the valve housing while facing the front end surface of the movable core. a valve spring that biases the valve body in the valve-closing direction; and a valve spring that moves the movable core away from the valve-opening side stopper to allow the valve body to close when the coil is not energized. The electromagnetic fuel injection valve is provided with an auxiliary spring that urges the movable core to come into contact with a valve-side stopper, and the movable core has an opening at its rear end surface and a bottom surface that is closer to the movable core than the center of gravity of the movable core. The first feature is that an annular recess located on the front end surface side of the core is provided, the auxiliary spring is accommodated in the annular recess, and the front end of the auxiliary spring is supported on the bottom surface.

In addition to the first feature, the present invention also provides that the valve-opening side stopper is formed of a cylindrical body, and the front end surface of the cylindrical body is connected to the spring seat surface that supports the rear end of the auxiliary spring, and the spring seat surface that supports the rear end of the auxiliary spring. A second aspect of the present invention is to provide a notch on the outer periphery of the cylindrical body that defines a fuel passage between the cylindrical body and the inner periphery of the fixed core, the contact surface being pushed by the movable core when the coil is energized. Features.

Furthermore, in addition to the first or second feature, the present invention provides a third feature in which the movable core is provided with a fuel hole that communicates between both front and rear end surfaces thereof and overlaps a part of the annular recess. The characteristics of

According to the first feature of the present invention, the pressing force of the auxiliary spring on the movable core acts on the front end side of the movable core rather than the center of gravity of the movable core. Therefore, when the movable core is in a floating state where it does not come into contact with either the valve-opening side stopper or the valve-closing side stopper, even if the pressing force of the auxiliary spring against the movable core fluctuates in each part, the moment generated in the movable core is suppressed. It is possible to prevent the movable core from tilting, which contributes to improving the responsiveness of the movable core when the coil is energized, and to suppressing bouncing of the movable core when the coil is de-energized. In addition, when the coil current is cut off, the annular, wide-area outer front end surface of the movable core comes into contact with the valve-closing stopper fixed to the valve housing, which effectively contributes to suppressing bouncing of the movable core. obtain.

According to the second feature of the present invention, the valve-opening side stopper is formed of a cylindrical body, and the front end surface of this cylindrical body is used as a support surface that supports the rear end of the auxiliary spring, and a movable part when the coil is energized. The shape of the valve-opening side stopper is simple because it has a contact surface that is pushed by the core, and a notch is provided on the outer periphery of this cylindrical body to define a fuel passage between it and the inner circumferential surface of the fixed core. This can contribute to reducing the cost of electromagnetic fuel injection valves.

According to the third feature of the present invention, the fuel passage of the movable core and the annular recess partially overlap, so that fuel can be prevented from staying in the annular recess.

1 is a longitudinal sectional view showing an embodiment of an electromagnetic fuel injection valve for an internal combustion engine according to the present invention. FIG. 3 is an enlarged view showing the vicinity of the movable core of the fuel injection valve in a closed state. FIG. 3 is a diagram corresponding to FIG. 2 showing the open state of the fuel injection valve. A cross-sectional view taken along line 4-4 in FIG. 2. FIG. 3 is a perspective view of the valve opening side stopper in FIG. 2; FIG. 2 is an explanatory diagram of the operation of the present invention. An explanatory diagram of the operation of the prior art.

Embodiments of the present invention will be described with reference to the accompanying FIGS. 1 to 3.

First, in FIG. 1, a cylinder head 5 of an internal combustion engine E is provided with a mounting hole 7 that opens into a combustion chamber 6, and an electromagnetic fuel injection valve I of the present invention that can inject fuel toward the combustion chamber 6 is installed. is mounted in the mounting hole 7. In the electromagnetic fuel injection valve I of the present invention, the fuel injection side is the front side, and the opposite side is the rear side.

The valve housing 9 of this electromagnetic fuel injection valve I includes a hollow cylindrical housing body 10, a valve seat member 11 that fits and is welded to the inner periphery of the front end of the housing body 10, and a rear end of the housing body 10. A magnetic cylindrical body 12 is welded to the housing body 10 with its front end fitted to the outer periphery of the magnetic cylinder 12, and a non-magnetic cylindrical body 13 whose front end is coaxially connected to the rear end of the magnetic cylinder 12. Ru. A front end of a cylindrical fixed core 14 having a hollow part 15 is coaxially connected to the rear end of the non-magnetic cylindrical body 13, and a fuel supply connected to the hollow part 15 is connected to the rear end of the fixed core 14. The tubes 16 are integrally and coaxially connected.

The magnetic cylindrical body 12 has a flange-shaped yoke part 12a integrally in its axially intermediate part, and is accommodated in an annular recess 17 provided in the cylinder head 5 so as to surround the outer end of the mounting hole 7. A cushioning material 18 is interposed between the cylinder head 5 and the yoke portion 12a.

At the entrance of the fuel supply cylinder 16, an orifice member 24 and a fuel filter 19 adjacent to the orifice member 24 on the downstream side are installed. A fuel supply cap 21 branched from a fuel distribution pipe 20 connected to a discharge port of a fuel pump (not shown) is fitted into the fuel supply tube 16 via an annular seal member 22 . A bracket 23 is secured to the top of the fuel supply cap 21, and this bracket 23 is removably fastened to the cylinder head 5 by bolts or the like to a support (not shown) that is erected on the cylinder head 5.

An elastic member 26 made of a leaf spring is interposed between the fuel supply cap 21 and an annular stepped portion 25 provided in the middle of the fuel supply cylinder 16 and facing the fuel supply cap 21 side. The electromagnetic fuel injection valve I is held in the cylinder head 5 by the elastic force exerted by the elastic member 26.

The valve seat member 11 has a bottomed cylindrical shape with an end wall portion 11a at the front end, and a conical valve seat 27 is formed on the end wall portion 11a. A plurality of fuel nozzle holes 28 are provided that open near the center of the fuel injection hole 27 . The valve seat member 11 is fitted and welded to the front end of the housing body 10 so that the fuel injection hole 28 opens toward the combustion chamber 6. That is, the valve housing 9 is configured to have a valve seat 27 at its front end.

A coil assembly 30 is fitted onto the outer peripheral surface of the magnetic cylindrical body 12 from the rear end to the fixed core 14 . This coil assembly 30 consists of a bobbin 31 that fits on the outer peripheral surface, and a coil 32 that is wound around the bobbin 31. The front end of a magnetic coil housing 33 that surrounds this coil assembly 30 is It is combined with the magnetic cylinder 12.

The outer periphery of the rear end of the fixed core 14 is covered with a synthetic resin coating layer 34 that is molded so as to be continuous with the rear end of the coil housing 33 . A coupler 34a holding the electromagnetic fuel injection valve I is integrally formed so as to protrude from one side thereof.

The rear end of the non-magnetic cylindrical body 13 is fitted to the front end of the fixed core 14 so that its outer peripheral surface is connected to the fixed core 14, and welded in a liquid-tight manner.

A valve body 40 and a movable core 41 are accommodated in the valve housing 9 extending from the valve seat member 11 to the non-magnetic cylindrical body 13. The valve body 40 includes a valve portion 42 that opens and closes the fuel injection hole 28 in cooperation with the valve seat 27, and a rod 43 that extends into the fixed core 14.

The valve portion 42 is formed into a spherical shape so as to slide within the valve seat member 11, and the rod 43 is formed to have a smaller diameter than the valve portion 42. An annular fuel passage 44 is defined between the valve seat member 11 and the rod 43, and a plurality of flat parts 45 are formed on the outer circumferential surface of the valve portion 42 to define fuel passages between the valve seat member 11 and the rod 43. be done.

As shown in FIGS. 2 and 3, a valve-opening stopper 48 is fixed to the upper end of the rod 43 and is slidably disposed in the hollow portion 15 of the fixed core 14. As shown in FIGS. At this time, the rod 43 is inserted into the center hole 48a of the valve opening side stopper 48, and the valve opening side stopper 48 is fixed to the rod 43 by welding at the insertion portion.

As shown in FIGS. 2, 3, and 5, the valve opening side stopper 48 is formed of a cylindrical body, and the outer periphery thereof has a plurality of planar notches 48b arranged at equal intervals along the circumferential direction. These notches 48b define a fuel passage 52 between the inner peripheral surface of the fixed core 14 and the front and rear end surfaces of the valve-opening stopper 48, which communicate with each other.

Referring again to FIGS. 1 and 2, a pipe-shaped retainer 53 is fitted into the hollow portion 15 of the fixed core 14 and fixed by caulking. A valve spring 54 made of a coil spring is compressed between the retainer 53 and the rear end surface of the valve opening side stopper 48 and biases the valve body 40 in the seating direction on the valve seat 27, that is, in the valve closing direction. Ru. At this time, the rear end of the rod 43 protrudes from the rear end surface of the valve-opening stopper 48 and fits into the inner periphery of the front end of the valve spring 54, thereby serving to position the valve spring 54.

The movable core 41 is slidably fitted into the inner peripheral surface of the valve housing 9, with its rear end surface (suction surface 41a) facing the front end surface (suction surface 14a) of the fixed core 14. The movable core 41 is provided with a through hole 41b at its center, through which the rod 43 is slidably inserted.

An annular valve-closing stopper 49 facing the outer peripheral front end surface of the movable core 41 is press-fitted and fixed to the inner peripheral surface of the magnetic cylindrical body 12 . To position the valve-closing stopper 49, an annular positioning step 47 is formed on the inner periphery of the magnetic cylinder 12 to support the front end surface of the outer peripheral portion of the valve-closing stopper 49.

An auxiliary spring 55 made of a coil spring is provided between the movable core 41 and the valve-opening stopper 48 to bias the movable core 41 toward the valve-closing stopper 49 . The set load of this auxiliary spring 55 is set smaller than that of the valve spring 54.

Referring again to FIGS. 2 to 4, the movable core 41 is provided with an annular recess 51 concentric with the movable core 41. As shown in FIGS. This annular recess 51 opens at the rear end surface of the movable core 41 and is formed such that its bottom surface 51 a is located closer to the front end surface of the movable core than the center of gravity G of the movable core 41 . The auxiliary spring 55 is housed in the annular recess 51, and the front end of the auxiliary spring 55 is supported by the bottom surface 51a of the annular recess 51. Therefore, the bottom surface 51a of the annular recess 51 serves as a spring seat that supports the front end of the auxiliary spring 55, away from the center of gravity G of the movable core 41 toward the front end surface of the movable core.

On the other hand, the flat front end surface of the valve opening side stopper 48 serves as a spring seat surface that supports the rear end portion of the auxiliary spring 55 and a contact surface that is pressed against the movable core 41 when the coil is energized. .

Further, the movable core 41 is provided with a plurality of annularly arranged fuel holes 58 that communicate between the front and rear end surfaces of the movable core 41 and overlap with a portion of the annular recess 51 .

Therefore, when the valve body 40 is in the valve closing position and the movable core 41 is in the abutting position with the valve closing side stopper 49, the front end surface (suction surface 14a) of the fixed core 14 and the rear end surface of the movable core 41 (The suction surface 41a), a gap corresponding to the opening/closing stroke of the valve body 40 is ensured, and the front end surface of the valve-opening side stopper 48 occupies an intermediate position of the gap. Therefore, when the fixed core 14 attracts the movable core 41 as the coil 32 is energized, the movable core 41 first comes into contact with the valve-opening side stopper 48 and is attracted to the fixed core 14 while being pushed. .

2 to 4, reference numeral 36 indicates a sliding gap between the valve housing 9 and the movable core 41, reference numeral 37 indicates a sliding gap between the movable core 41 and the rod 43, and reference numeral 38 indicates a sliding gap between the fixed core 14 and the valve opening. The sliding gap between the side stoppers 48 is shown.

Next, the operation of this embodiment will be explained.

In the electromagnetic fuel injection valve I, when the coil 32 is not energized, the valve body 40 is pressed by the set load of the valve spring 54 to close the fuel injection hole 28 by seating on the valve seat 27. state. In this valve-closed state, high-pressure fuel discharged from a fuel pump (not shown) into the fuel distribution pipe 20 is supplied to the fuel supply cylinder 16 through the fuel supply cap 21, and the inside of the fuel injection valve I, that is, the fuel supply pipe 16, is The retainer 53, the fuel passage 52 in the fixed core 14, the fuel passage 58 and annular recess 51 of the movable core 41, and the inside of the valve housing 9 are filled and on standby.

At this time, the pulsations in the fuel pressure that occur in the fuel distribution pipe 20 due to variations in the discharge pressure of the fuel pump, etc., are attenuated by the orifice of the orifice member 24 at the inlet of the fuel supply cylinder 16, and the pulsations are transferred to the inside of the fuel injection valve I. Eliminate or reduce the impact of

On the other hand, as shown in FIG. 2, in such a valve-closing state, the movable core 41 is held in contact with the valve-closing stopper 49 by the set load of the auxiliary spring 55, and there is no space between the movable core 41 and the fixed core 14. The predetermined distance is maintained.

When the coil 32 is energized in such a valve closed state, the movable core 41 is attracted to the fixed core 14 by the magnetic force generated between the fixed core 14 and the movable core 41, so first, while compressing the auxiliary spring 55, It slides backward on the rod 43 and comes into contact with the valve opening side stopper 48. That is, when the movable core 41 initially moves, it approaches the fixed core 14 while quickly compressing the auxiliary spring 55, which has a smaller set load than the valve spring 54, and rapidly increases the suction force from the fixed core 14, so that it moves at an accelerated pace. Then, as shown in FIG. 3, the valve opening side stopper 48 is pressed.

Therefore, the movable core 41 quickly moves further rearward against the large set load of the valve spring 54 while being accompanied by the valve opening side stopper 48, and is attracted to the suction surface 14a of the movable core 41.

The valve-opening stopper 48, which is thus pushed rearward by the movable core 41, is fixed to the rod 43 of the valve body 40, so that it displaces the valve portion 42 from the valve seat 27 and opens the valve. Become.

When the valve body 40 opens, high-pressure fuel waiting inside the valve housing 9 or the like is directly injected from the fuel injection hole 28 into the combustion chamber 6 of the internal combustion engine E. In this way, the valve-opening response of the valve body 40 can be improved, and the power consumption of the coil 32 can be reduced.

Next, when the coil 32 is de-energized, the valve opening side stopper 48 is pushed by the biasing force of the valve spring 54, so the valve opening side stopper 48, together with the valve body 40, immediately moves toward the valve seat 27 side. , the valve portion 42 is seated on the valve seat 27, the valve is closed, and fuel injection from the fuel injection hole 28 is stopped. This closed state of the valve body 40 is reliably maintained by a large set load of the valve spring 54.

Meanwhile, the movable core 41 is pushed forward by the biasing force of the auxiliary spring 55 and is received by the closing side stopper 49.

By the way, since almost the entirety of the auxiliary spring 55 is accommodated in the annular recess 51 of the movable core 41, its expansion and contraction movements are guided by the inner and outer circumferential surfaces of the annular recess 51, thereby preventing buckling of the auxiliary spring 55. can.

However, a minute gap exists between the auxiliary spring 55 and the inner and outer circumferential surfaces of the annular recess 51 to allow the auxiliary spring 55 to expand and contract. Therefore, when lateral vibration occurs in the auxiliary spring 55 due to engine vibrations, etc., and when the movable core 41 moves backward or forward, the movable core 41 moves toward either the valve-opening side stopper 48 or the valve-closing side stopper 49. For example, as shown in FIG. 6, the pressing force of the auxiliary spring 55 against the bottom surface 51a of the annular recess 51 in the movable core 41 increases at both ends of the bottom surface 51a in the diametrical direction. A difference such as F1>F2 may occur. According to such a difference in pressing force, a tilting moment M around the center of gravity G acts on the movable core 41, but since the points of action of F1 and F2 are below the center of gravity G, the moment M causes the movable core to When 41 is tilted, a restoring moment M' is immediately generated due to the Yajirobe effect.

As a result, the movable core 41 can contact the valve-closing side stopper 49 and the fixed core 14 with no or a proper posture with little inclination. This not only prevents abrasion of the contact portion, but also improves the responsiveness of the movable core 41 when the coil 32 is energized, thereby stabilizing the valve opening characteristics of the valve body 40, and also cuts off the energization of the coil 32. In some cases, bouncing can be suppressed by preventing the movable core 41 from abutting unevenly on the valve-closing side stopper 49.

Moreover, when the coil 32 is de-energized, the annular, wide-area outer peripheral front end surface of the movable core 41 comes into contact with the valve-closing stopper 49 fixed to the valve housing 9, thereby preventing the movable core 41 from bouncing. Suppression can be achieved more effectively.

Further, the valve opening side stopper 48 is composed of a cylindrical body, and the front end surface of this cylindrical body is pushed by the spring seat surface that supports the rear end of the auxiliary spring and the movable core 41 when the coil 32 is energized. Since a notch 48b is provided on the outer peripheral surface of this cylindrical body and defines a fuel passage 52 between it and the inner periphery of the fixed core 14, the shape of the valve-opening side stopper 48 is changed. By simplifying the above, it is possible to reduce the cost of the electromagnetic fuel injection valve I.

Furthermore, the movable core 41 is provided with a plurality of fuel holes 58 that communicate between its front and rear end surfaces and overlap a part of the annular recess 51, so that fuel passes through the fuel holes 58 of the movable core 41. At this time, a flow of fuel also occurs within the annular recess 51, and it is possible to prevent fuel from staying in the annular recess 51.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the present invention as set forth in the claims. It is possible. For example, the notch 48b on the outer peripheral surface of the valve-opening side stopper 48 may be formed in the shape of a groove. Further, the valve closing side stopper 49 can also be formed integrally with the inner periphery of the valve housing 9.

I...Electromagnetic fuel injection valve G...Center of gravity 9 of movable core...Valve housing 12...Magnetic cylindrical body 13...Non-magnetic cylindrical body 14...Fixed core 14a... Suction surface 15...hollow part 27...valve seat 32...coil 40...valve body 41...movable core 41a...suction surface 41b...movable core through hole 42...valve Part 43... Rod 48... Valve opening side stopper 48a... Center hole 48b... Notch 49... Valve closing side stopper 51... Annular recess 51a... Bottom surface 52 of the annular recess... Fuel Passage 54...Valve spring 55...Auxiliary spring 58...Fuel hole

Claims (3)

A valve housing (9) having a valve seat (27) at the front end, a hollow fixed core (14) connected to the rear end of the valve housing (9), and arranged around the outer periphery of the fixed core (14). a coil (32) provided therein, a valve body (40) in which a rod (43) is connected to a valve portion (42) that cooperates with the valve seat (27), and a front end of the fixed core (14). A movable core (41) is slidably disposed in the valve housing (9) while facing the surface thereof, and has a through hole (41b) in the center that is penetrated by the rod (43); (43) and is slidably disposed in the hollow part (15) of the fixed core (14), and is attracted to the fixed core (14) when the coil (32) is energized. A valve-opening stopper (48) that is pushed by the core (41) to open the valve body (40), and a stopper (48) on the inside of the valve housing (9) facing the front end surface of the movable core (41). An annular valve-closing side stopper (49) protruding from the peripheral surface, a valve spring (54) that biases the valve body (40) in the valve-closing direction, and a valve spring (54) that biases the valve body (40) in the valve-closing direction; Assist for urging the movable core (41) away from the valve-opening stopper (48) and into contact with the valve-closing stopper (49) to allow the valve body (40) to close. An electromagnetic fuel injection valve comprising a spring (55),
The movable core (41) has an annular recess (51a) which is open at the rear end surface and whose bottom surface (51a) is located closer to the front end surface of the movable core (41) than the center of gravity (G) of the movable core (41). 51), the auxiliary spring (55) is accommodated in the annular recess (51), and the front end of the auxiliary spring (55) is supported on the bottom surface (51a). injection valve. The valve-opening side stopper (48) is formed of a cylindrical body, and the front end surface of the cylindrical body serves as a spring bearing surface that supports the rear end of the auxiliary spring (55) and when the coil (32) is energized. A notch (48b) serving as an abutment surface that is pushed by the movable core (41) and defining a fuel passage (52) between the outer periphery of the cylindrical body and the inner periphery of the fixed core (14). The electromagnetic fuel injection valve according to claim 1, further comprising: an electromagnetic fuel injection valve. According to claim 1 or 2, the movable core (41) is provided with a fuel hole (58) that communicates between its front and rear end surfaces and overlaps a part of the annular recess (51). The electromagnetic fuel injection valve described.