JPS611860A - Fuel injection solenoid valve - Google Patents

Abstract

PURPOSE:To improve productivity and reliability, by coating a part of the terminal with resin of plastic or the like after the part of the terminal is deformed by plasticity. CONSTITUTION:A fuel injection valve 1 is assembled in an order such that an O ring B15 for sealing fuel and a terminal guide 22 holding the O ring B15 are mounted to a terminal 17 after inserting a bobbin 11 into the assembly unit of a yoke 2 and a core 21. Thereafter, a part of the terminal 17 is pressed from the direction of an arrow head and deformed by plasticity. And this constitution, allowing resin to flow into this plastic deformation part, enables the fuel injection valve 1 to promote holding of the bobbin 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an electromagnetic fuel injection valve, and particularly to one having a groove suitable for fixing a coil assembly.

[Background of the invention]

A method of attaching the bobbin 11 with a coil wound around the center of the member that combines the core 21 and the yoke 2 as shown in FIG. This is a type of welding in which a member such as a pipe-shaped glass is locally heated and deformed into a brim shape to form a hanging portion 19. However, in this method, there are generally two hanging parts 19,
Since the wall thickness is about 1 mm, it may break due to engine vibration, and there is a concern that the bobbin 11 may fall, especially since the engine has large thermal expansion due to cold heat (-45C to +140C). In addition, it is necessary to strictly control the welding conditions, and the sulfide in the plastic that precipitates when the hanging part 19 is melted accelerates the deterioration of the O-ring 15, which tends to cause leakage from the terminal 17 part. No consideration was given to productivity and reliability.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electromagnetic fuel injection valve which eliminates the drawbacks of the prior art described above and has a suitable structure in terms of productivity and reliability.

[Summary of the invention]

The present invention incorporates a bobbin into the button solid body of the core and yoke,
After plastically deforming a part of the terminal integrally attached to the bobbin, the plastically deformed part is covered with a resin such as plastic to hold the bobbin.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. Fuel pressurized by the fuel pump is mainly supplied through an inlet 12 opened in the yoke 2, passes through the inner and outer peripheries of the bobbin 11, flows out from an outlet 13, and is returned to the fuel tank via a fuel pressure regulator placed nearby. Therefore, the fuel pressure around the outer circumference of the valve 3 is held substantially constant, and the amount of injection from the nozzle 6 is controlled by the opening time of the valve 3. A current determined by the operating conditions of the engine is applied to the coil 23 in the bobbin 11 from the terminal 17, and the plunger 4 integrated with the valve 3 is moved upward to open the valve. The valve 3 is guided concentrically by a valve guide 5 to stabilize opening and closing operations. When the current to the coil 23 is cut off, the spring 8 pushes back the valve 3 and closes it. The pressing force of spring B is 0 ring Al (spring adjuster 9 with l).
Adjust with. The fuel injected according to the above-mentioned principle is atomized from the nozzle 6 by the swirler 7 having an oblique hole.

Since the opening/closing cycle of the valve 3 reaches approximately 300 Hz, the heat generated by the coil 23 is also large, causing changes in characteristics and safety issues. Therefore, a method for forcibly cooling the coil 23 is provided by providing a circulation groove 18 on the outer periphery of the coil 23 and an inner surface of the bobbin 9, and a circulation path 14 on the outer periphery.

In such a configuration, the order of assembling the fuel injection valve 1 is to attach the bobbin 11 to the yoke 2 and core 210 assembly, then attach the O-ring B15 for fuel seal, and
The terminal guide 22 holding the ring Bl 5 is attached to the terminal 17. Thereafter, a part of the terminal 17 is pressed in the direction of the arrow as shown in FIG. 2 to plastically deform it.

At this time, 1. Since the change in the effective cross-sectional area of the terminal 17 is small, it is possible to prevent the terminal 170 from generating heat due to an increase in current density.

2. It is possible to prevent the terminal guide 16 and the O-ring B1ε from being removed and to prevent the bobbin 11 from falling off when the plastically deformed part is covered with resin and carried to the work process.

3. During the work of covering the plastically deformed portion with resin, the plastically deformed portion acts as a stopper, so it is possible to prevent the bobbin 11 from falling off due to injection pressure.

There are advantages such as

With such a configuration, the resin flows into this plastically deformed portion, and the bobbin 11 can be held.

Modifications of this embodiment are shown in FIGS. 3 and 4. FIG. 4 shows a structure for bending the terminal 17, and FIG. 5 shows a structure for compressing the terminal 17 in the vertical direction to form a ring.

〔Effect of the invention〕

According to the present invention, it is only necessary to plastically deform a part of the terminal, and welding can be eliminated, which is effective in improving productivity and reliability.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an electromagnetic fuel injection valve of the present invention, FIG. 2 is a sectional view taken along line a-a in FIG. A vertical sectional view of the injection valve, FIG. 5 is a sectional view of a conventional electromagnetic fuel injection valve.

Claims (1)

[Claims] 1. An electromagnetic fuel injection valve that has a coil assembly including a fixed iron core and an electromagnetic coil inside the injection valve body, and the coil assembly is attached to the fixed iron core from below. An electromagnetic fuel injection valve in which a part of a terminal integrally attached to the coil assembly is plastically deformed after being inserted into a fixed iron core, and the plastically deformed part is covered with resin such as plastic.