JPS60240865A - Electromagnetic type fuel injecting valve - Google Patents

Abstract

PURPOSE:To reduce the generation of fuel steam and to enable given fuel to be alway fed through a nozzle, by a method wherein a passage, through which fuel flows, is located between the outer periphery on the inner side of a bobbin, around which a coil is wound, and the wall surface, which is positioned opposite to the outer periphery of the bobbin, a core positioned concentrically with the bobbin. CONSTITUTION:With a coil 3 energized, a plate 7 is sucked to rais a ball valve 6, which is separated from a valve seat 13. Said opening of the valve causes fuel to flow through an inlet passage 18 and be injected through a nozzle 17 by means of an oblique hole 15 in a swril orifice 16 as an eddy flow is produced. Further, an annular passage 26 is formed between the outer periphery on the inner side of a bobbin 2, around which a coil 3 is wound, and the wall surface of a core 1. This causes fuel steam, generated at the upper surface of the coil 3, to be exhausted through an outlet passage 22 by means of the annular passage 26. Further, the outer periphery on the inner side of the bobbin 2, around which the coil 3 is wound, is cooled directly by fuel to reduce the generation of fuel steam.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a magnetic type fuel injection valve, particularly for supplying fuel to an engine, which is suitable for effectively eliminating fuel vapor generated during transportation. This invention relates to electromagnetic fuel injection valves.

[Background of the invention]

The conventional electromagnetic fuel injection valve is Br! f Kaisho 57 = 195
As shown in FIG. 1 shown in Japanese Patent No. 858, core 1
Attach the coil 3 to the bobbin 2 arranged concentrically on the
Surrounded by the yoke 4 and the stopper 5, a plate 7 integrated with the ball valve 6 is disposed below the stopper 5, and is shibrated by the electromagnetic force generated when the coil 3 is energized via the terminal 8. 7 is suctioned, and the pressure by the spring 10 is adjusted using the adjustment screw 9, and the ball valve 6 is moved upward, and the pulp guide 1 attached to the nozzle holder 11 is moved upward.
The valve is opened by separating it from the second valve seat 13. The pulp guide 12 is airtightly coupled to the nozzle holder 11 via an O-ring 14, and the nozzle 17 is coupled to the pulp guide 12 via a swirl orifice 16 provided with a plurality of oblique holes 15. It is.

When the ball valve 6 opens, fuel flows through the inlet passage 18, 18' opened in the yoke 4, passes through the inner periphery of the lower end of the core 1, passes through multiple passages provided in the plate 7 and the pulp guide 212, and Furthermore, it passes between the ball valve 6 and the valve seat 13 of the pulp guide 12, and is injected through the nozzle 17 while forming a vortex through the diagonal hole 15 of the swirl orifice 16. 19 is a member for adjusting the amount of movement of the ball valve 6; 20 is a member 0 for making airtight between the adjusting screw 9 and the core 1;
The ring 21 is a filter that prevents dirt and the like from flowing in from the inlet passage 18, 18', the outlet passage 1, and the passage 22.

However, in the electromagnetic fuel injection valve with the above structure, fuel vapor is generated around the ball valve 6 and in the lower end space of the coil 3 in the core 1 during long idling operation at high temperatures or when starting the engine after stopping. As a result, a predetermined amount of fuel cannot be supplied from the nozzle 17. Therefore, a passage 23 connected to the spring 10 side is provided on the side surface of the lower end of the core 1, and the fuel vapor generated around the spring 10 is transferred to the passage 23, the space 24, and the passage 2.
5 to the outside from the outlet passage 22. However, if the inner surface of the core 1 is poorly finished, the space 24 in the center of the core 1, which houses the adjustment screw 9 and the spring 10, will have many nuclei, which will increase the generation of fuel vapor. Therefore, precise finishing is required, leading to an increase in price. Further, since a portion of the fuel flows around the outer periphery of the spring 10, the flow of the fuel is disturbed and the generation of fuel vapor increases. Furthermore, if the concentricity between the adjustment screw 9 and the space 24 is poor, the swinging motion of the seat of the spring 10 will increase, causing the spring 1
There is also the problem that it is difficult to keep the force constant when pressing at zero.

[Purpose of the invention]

The present invention has been made in view of the above, and an object of the present invention is to provide an electromagnetic fuel injection valve that can significantly reduce the generation of fuel vapor.

[Summary of the invention]

A feature of the present invention is that a hole is provided in the center for inserting an adjustment screw to adjust the pressing force of the spring that presses the ball valve with the integrated plate against the valve seat of the pulp guide. The present invention is characterized in that a passage through which fuel flows is provided between the inner periphery of the bobbin around which the saturated coil is wound and the opposing wall surface of the core.

[Embodiments of the invention]

The present invention will be explained in detail below using the embodiment shown in FIG.

FIG. 2 is a longitudinal cross-sectional view showing one embodiment of the electromagnetic fuel injection device of the present invention. The same parts and the same working elements as in FIG. In Figure 2, the inner periphery of the bobbin 2 on which the coil 3 is wound and the core 1 are shown.
An annular passage 26 is formed between the wall surface and the wall surface. Therefore, the fuel vapor generated on the lower surface of the coil 3 is transferred to the annular passage 2.
6 and is discharged through an outlet passage 22. Note that since the annular passage 26 is formed between the outer circumferential wall surface of the core 1 formed by machining with a cutting tool and the inner circumferential surface of the bobbin 2 formed by plastic molding, both formed surfaces are in good condition. Fuel vapor generation due to flow turbulence is significantly reduced.

Additionally, processing time is reduced. Further, a plurality of groove passages 27 and 28 are provided on the outer periphery of the bobbin 2 to allow fuel vapor to flow out.

According to the embodiment of the present invention described above, since the inner and outer circumferences of the bobbin 2 around which the coil 3 is wound are directly cooled by the fuel,
Fuel vapor generation is significantly reduced.

It's a trench, because the fuel flowing around Hane 10 decreases,
Disturbance of the fuel flow caused by the splashes 10 and generation of fuel vapor due to the vibrations of the splashes 10 are reduced. Furthermore, since the adjustment screw 9 may have a simple shape as shown in the figure, the amount of processing is reduced, and since the length of the guide portion of the adjustment screw 9 is increased, concentricity is improved and the amount of oscillation is reduced.

Note that the annular passage 26 may be formed of a plurality of vertical grooves, and the same effect can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, the generation of fuel vapor can be significantly reduced, and a predetermined amount of fuel can always be supplied from the nozzle.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a conventional electromagnetic fuel injection valve, and FIG. 2 is a vertical cross-sectional view showing an embodiment of the electromagnetic fuel injection valve of the present invention. 1...Core, 2...Bobbin, 3...Coil, 4...
...Yoke, 6...Ball valve, 7...Plate, 9...
・Adjustment screw, 10... Spring, 11... Nozzle holder, 12... Pulp guide, 13... Valve seat,
15... Oblique hole, 16... Swirl orifice, 17
... Nozzle, 18... Inlet passage, 22... Outlet passage, 26... Annular passage, 27.28...)' Groove passage. Agent Patent Attorney Akio Takahashi 51 Figure 1'/ /j)

Claims (1)

[Claims] 1. A core with a hole in the center for inserting an adjustment screw to adjust the pressing force of the spring that presses the ball valve with the integrated plate against the valve seat of the pulp guide. A bobbin on which a coil is wound concentrically is arranged, and when the coil is energized, the plate is attracted, the ball valve is separated from the valve seat, and the ball valve is moved from a nozzle provided below the ball valve. An electromagnetic fuel injection valve configured to inject fuel, characterized in that a passage through which fuel flows is provided between an inner periphery of the bobbin and an opposing wall surface of the core. . 2. The electromagnetic fuel injection valve according to claim 1, wherein the passage is an annular passage concentric with the inner circumference of the bobbin. 3. The electromagnetic fuel injection valve according to claim 1, wherein the passage is a multi-slot groove in the axial direction of the bobbin. 4. The bobbin is provided with a groove passage on its outer periphery for discharging generated fuel vapor.
L or the electromagnetic fuel injection valve according to item 2 or item 3.