JPS6098277A - Solenoid valve - Google Patents

Abstract

PURPOSE:To permit high-speed operation by inserting a ring made of slidable material into the magnetic gap part formed between a magnetic iron core yoke part and a magnetic plunger which performs reciprocative movement. CONSTITUTION:In operation, a plunger 4 is attracted to a core 3 side by a magnetic attraction force. A washer 12 connected with a ball valve 6 through spot welding collides with a stopper 10, and the direct collision of the plunger 4 onto the core 3 is prevented. The plunger 4 is fixed by fitting a ring 13 made of nonmagnetic slidable alloy into the gap formed between a yoke 2 and the plunger 4 by utilizing said gap. Thus, eccentric setting of the plunger 4 is prevented, and the stability of the injection flow-rate characteristic of fuel is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a solenoid valve, particularly a magnetic injection valve for fuel injection for a fuel injection device for an automobile, and is particularly suitable for a high i@operation injection device. related to electromagnetic injection valves.

[Background of the invention]

Fuel injection systems for internal combustion engines, particularly automobiles, are required to operate at higher speeds year by year, and these requirements are becoming increasingly strict, especially as the number of cars equipped with turbochargers increases recently.

The injection valve used in the conventional injection device is magnetically attracted as shown in FIG. The valve stem 5, which is directly connected to the granger 4, is stopped by a stopper 10 to prevent collision, and a structure that always maintains a constant distance between the granger 4 and the core 3, and a magnetic valve as shown in FIG. A structure that causes the granger 4 and core 3 to collide directly when the core 3 is attracted is required. These known injection valves having the above-mentioned type of structure have the following drawbacks, which make it difficult to put them to practical use as high-speed target injection valves.

That is, in the former structural type shown in FIG. 1, since the plunger 4 and the core 3 do not collide directly, when the valve stem 5 collides with the stopper 1O, the fuel is bounced in the opposite direction. In particular, this rebound is a cause of variations in characteristics, and has the disadvantage that it becomes larger as the speed of suction is faster, that is, when operating at a higher speed. In addition, in order to directly control the reciprocating movement of the valve stem, the ball valve 6 and valve #5 have a structure in which two points, the collar, slide against the inner wall, so the valve stem 5 does not move and is not long. This increases the weight, which slows down the response during suction and hinders high-speed operation. On the other hand, in the latter structural type shown in Fig. 2, the valve stem is removed and the ball valve 6 is attached directly to the plunger 4, so the moving part is very light and the response during suction is poor. However, since the Gra/jar 4 collides directly with the core 3, the magnetic deterioration of the collision surface of the Shock plunger 4 and the core 3 in the main part of the magnetic circuit due to the operation is large and the fuel injection characteristics are poor. There is a disadvantage of deterioration υ, and there is also an advantage that the bouncing phenomenon is reduced due to the S quantity of the moving part, but since there is no sliding part of the moving part, the linearity during suction is poor, and the granger 4 is unevenly attached to the core 3. Because of this, a very large collision force is applied to that part, causing major problems such as deformation of the plunger.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention was to provide an injection valve that is small, lightweight, and has a structure that prevents direct collision between the plunger and the core, and thereby provides an injection valve that can operate at high speed. I'm going to do it.

[Summary of the invention]

By removing the valve stem and integrating the plunger and ball valve to reduce the weight of the moving parts, we have improved responsiveness during suction, and also avoided magnetic deterioration by avoiding direct collision between the glass/jar and the core. In addition, the structure is such that the movable parts can reciprocate in parallel and prevent one-sided contact. The key point of the invention made to this end is to utilize the magnetic air gap between the pu, 7/ja and the yoke portion of the magnetic circuit. That is,
A sliding material is inserted into the gap to enable the reciprocating movement of the granger without causing friction, thereby reducing the parallel motion due to the removal of the valve stem.
It becomes possible to implement an injection valve having a structure that spins an L-side contact, which is capable of high-speed operation, and has excellent reliability.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings. Third
The figure shows the structure of the injection valve of the present invention. Since the valve stem is removed and the movable parts are lighter, it is suitable for low-pressure fuel injection valves with low fuel pressure.

As shown in Figure 3, the magnetic circuit part consists of a core 3, a yoke 2
The plunger 40 is composed of three plungers 40, and the two cores 3 and the yoke 2 are tightly connected by a caulking structure. The gra/jar 4 is directly connected to the ball valve 6, and when a pulse current is applied to the excitation coil l, the gra/jar 4 is magnetically attracted to the core 3 side, and the ball valve 6 opens from the valve seat 8, opening the nozzle/jar 4. Fuel is injected from I/9. Pulse - When the flow is cut off, it becomes gra/ja 4
is released from the magnetic attraction force and returned to its original state by the force of the spring 7, and the fuel stops flowing. During operation, the plunger 4 is attracted to the core side by magnetic attraction force, but the ball valve 6
A washer 12, which is joined by spot welding, hits the stopper 10 and prevents the plunger 4 from directly colliding with the core 3.The plunger 4 and core 3 always maintain a constant air gap. j? #) Prevents deterioration of magnetic properties due to 1jii impact. At this time, it is important that the movable parts move in parallel when reciprocating, and this is where the main point of the present invention lies. Utilizing the empty PJ between the yoke 2 and the plungers 4 and 0, fit all seven rings made of a non-magnetic sliding alloy into this gap and fix the plunger 4.
This prevents eccentricity and improves the stability of fuel injection flow rate characteristics. Next, the structure of this sliding portion will be explained. FIG. 4 shows an embodiment of the sliding portion between the yoke 2 and the glazer 40. This figure shows that the tip of the yoke 2 is machined into a wedge shape, and the part is machined into a wedge-shaped part with a sliding material, which is then fitted by plastic working to create a metal flow. It comes out. Tip 4 of yoke 2 in contact with pavit metal 13
The part is knurled so that a Babbitt metal A/13 ring fitted into the yoke 2 by plastic working is firmly fixed to the yoke 2.

By adopting this method, the weight is reduced by approximately 10%, especially,
7] The weight reduction of TFLS is large, and as a result, the rebound phenomenon upon collision with the stopper is significantly improved, and the linearity of the fuel injection flow rate characteristics with respect to the pulse width is extended to the low pulse width side, making it possible to reproduce the minimum injection flow rate. Got well. Moreover,!
! Since there is no collision between the air circuits, there is no deterioration of the magnetic X-temperature, so even after 2 billion repetitions of suction, the minimum injection flow rate changes within ±3316' for both human and sliding parts. Almost no wear was observed and it was found to be sufficiently durable.

FIG. 5 is a diagram showing an embodiment of a song according to the present invention.

A similar effect was observed with the shape shown in FIG. Furthermore, the same effect cannot be obtained even if the sliding material inserted into the opening IK of the yoke 2 and the plunger 4 is a thin plate made by a molten metal quenching method.

〔Effect of the invention〕

As described above, by utilizing the magnetic gap between the yoke 2 and the plunger 4 and fitting the sliding material 1 into the gap, a small and light-sized structure which is free from concerns about injection flow characteristics and has excellent durability can be achieved. For fuel injection [[Magnetic valve made possible.

[Brief explanation of drawings]

Figures 1 and 2 are structural diagrams of a conventional fuel injection valve, Figure 3 is a structural diagram of a fuel injection valve manufactured by Kazutomo I911 of the present invention, and Figure 4 is a structural diagram of a conventional fuel injection valve.
5 and 5 are enlarged views showing the sliding portion of the fuel injection valve.

Claims (1)

[Claims] 1. In a fuel injection device that fully opens and closes the υ valve using the magnetic attraction force of the seishite and the repulsive force of the spring, the magnetic core yoke part that constitutes the magnetic circuit t and the magnetic material graphite that reciprocates.
A solenoid valve characterized in that a ring made of a sliding material is inserted into the magnetic gap between the valve and the valve.