JPS595872A - Scroll type fuel injection valve - Google Patents

Abstract

PURPOSE:To facilitate assembling and reduce the generating rate of the failure of a nozzle body by a method wherein caulking is not employed to incorporate the main body of the nozzle. CONSTITUTION:A recess 1a is formed in the tip end part of a nozzle tube 1 while the nozzle body 7 is fitted into the recess 1a. The nozzle body 7 is constituted by abutting a pair of nozzle composing bodies 8a, 8b against each other and an eddy current chamber 9 is formed in the nozzle body. A retainer ring 16 is attached to the tip end side of the recess 1a and a disc spring 17, elastically contacting with the nozzle body 7, is interposed between the retainer ring 16 and the nozzle body 7. According to this constitution, a strong external force will never be applied when the nozzle body 7 is incorporated and the deformation of the nozzle body 7 or the deformation of the eddy current chamber 9 may be prevented. Accordingly, the nozzle body 7 may be incorporated with a good accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spiral fuel injection valve that injects fuel through a swirl chamber.

Conventionally, electromagnetic spiral fuel injection valves are widely known as this type of fuel injection valve. This electromagnetic fuel injection valve accommodates a nozzle body having a swirl chamber inside the tip of a nozzle barrel, forms a fuel inflow chamber inside the base end thereof, and connects this inflow chamber with the swirl chamber. By opening and closing the injection passage with a valve body, fuel is injected from the nozzle hole through the swirl chamber of the nozzle body. In addition, in such an electromagnetic type, an electromagnetic coil is arranged outside the nozzle cylinder, and the valve stem member of the valve body is made of a magnetic material, and when the electromagnetic coil is energized, the valve body is This lift is used to open and close the valve.

By the way, in the fuel injection valve having the above structure, conventionally, the nozzle body is housed inside the tip of the nozzle cylinder, and then the tip is fixed by caulking. Therefore, this caulking may cause problems such as deformation of the swirl chamber of the nozzle body, and there is a problem that the amount of fuel injection cannot be controlled with high precision.

Furthermore, even if the nozzle body is replaced when the swirl chamber is significantly deformed, it is impossible to replace the nozzle body because it is caulked and fixed to the nozzle tube. There was a problem where the entire valve was defective.

Furthermore, in electromagnetic fuel injection valves, the nozzle tube must be made of a non-magnetic material such as stainless steel (SUS 303), but such non-magnetic materials have poor caulking properties and are difficult to assemble. It was impossible to do so.

This invention was made based on these circumstances, and its purpose is to facilitate assembly, ensure highly accurate control of fuel injection amount, and reduce the incidence of defective products of the entire injection valve. An object of the present invention is to provide a spiral fuel injection valve that can perform the following steps.

That is, the present invention is characterized in that a nozzle body is fitted inside the tip of the nozzle tube, and this nozzle body is detachably held by a retaining ring.

An embodiment of the present invention will be described below based on the drawings, in which reference numeral 1 represents a nozzle tube made of a non-magnetic stainless steel material, and a fuel inflow chamber 2 is formed inside the base end of the nozzle tube 1. . Further, a fuel introduction pipe 3 is connected to the base end of the nozzle tube 1, and this fuel introduction pipe 3 communicates with the inflow chamber 2. 4 is an O-ring that keeps the inflow chamber 2 liquid-tight. A thread 5 is formed on the inner periphery of the base end of the fuel introduction pipe 3, so that the fuel introduction pipe 3 can be connected to an external fuel pipe (not shown).

Further, a filter 6 is installed inside the fuel introduction pipe 3, so that fuel is supplied to the inflow chamber 2 through this filter 6.

On the other hand, a recess 1a is formed inside the tip of the nozzle tube 1, and a nozzle body 7 is fitted into the recess 1a. The nozzle body 7 is constructed by abutting a pair of nozzle structures 8a*8b, and has a swirl chamber 9 formed therein.

The swirl chamber 9 and the inflow chamber 2 are connected to the injection passage 1.
For example, the injection passage 10 is
A communication path 12 is formed in the partition wall 11 that partitions the concave portion 1a of the nozzle cylinder 1 and the inflow chamber 2, and the communication path 12 is formed in the nozzle structure 8a on the partition wall 11 side. A vortex guide path 13 is formed to connect J2 and the vortex chamber 9. Note that the openings 14, 14 (one of which is shown) of the vortex guide path 13 in the vortex chamber 9 are located off both sides of the axis of the vortex chamber 9, and the nozzle structure on the tip side is located on this axis. A nozzle hole 15 is formed in 8b.

A retaining ring 16 is attached to the tip side of the recess 1a, and a disc spring 17 is interposed between the retaining ring 16 and the nozzle body 7 to make elastic contact with the nozzle body 7. ing. Therefore, the nozzle body 7 is detachably held by the retaining ring 16.

The opening of the communication passage 12 to the inflow chamber 2 is formed as a valve hole 18, and a conical valve body 19 for opening and closing the valve hole 18 is arranged in the inflow chamber 2. In this embodiment, the valve body 19 is made of an elastic material such as rubber, and is fixed to the tip of the valve stem member 20 by baking or the like. This valve stem member 2θ is housed in the inflow chamber 2 so as to be slidable in the tube axis direction, is made of a magnetic material, and is actuated by an electromagnetic drive unit 21.

That is, this electromagnetic drive section 21 does not have a coil case 22 attached to the outer periphery of the base end side of the nozzle tube 1, and both open ends of this coil case 22 are connected to end plates 23.・Occupation on 24th,
has been done. Note that the end plate 24 on the rear end side of the coil case 22
is integrally joined to this coil case 722 and attached to the fuel introduction pipe 3.

A sgur 25 is fitted onto the outer surface of the nozzle tube 1 within the coil turf 22, and an electromagnetic coil 26 is wound around this sgur 25.

Therefore, a magnetic circuit is formed by energizing the electromagnetic coil 26, and the electromagnetic force causes the valve stem member 20 to
The valve body 19 is sucked upward in the drawing to displace the valve body 19 from the valve hole 18 and open the valve hole 18. Further, a return spring 27 is provided between the valve stem member 2o and the tip of the fuel introduction pipe 3, and the valve body 19 is always urged downward in the direction of closing the valve hole 18. ing.

The windings of the electromagnetic coil 26 are led to the connector part 28 and connected to terminals 29 and 29 (only one shown), and the energization of the electromagnetic coil 26 is controlled by a computer (not shown). It is supposed to be done.

In the fuel injection valve having such a configuration, high-pressure fuel flows into the inflow chamber 2 through the fuel introduction pipe 3, and at this time, the valve body 19 is pushed into the valve hole 18 by the biasing force of the return spring 27. is closed. Then, the electromagnetic coil 2
6 is energized, the valve body 19 lifts upward against the return spring 27 and rises to a position where the valve stem member 20 comes into contact with the fuel introduction pipe 3. As a result, the valve hole 18 is opened, and the fuel in the inflow chamber 2 is forced into the vortex chamber 9 of the nozzle body 7 through the injection passage 10, and is atomized in the process of being swirled in the vortex chamber 9. , is injected from the nozzle hole 15. Therefore, according to such a fuel injection valve, the atomization of the fuel becomes good, and the fuel efficiency of the engine can be improved.

However, according to the above embodiment, the nozzle body 7 is fitted inside the tip of the nozzle tube 1 via the retaining ring 16, so that the assembly can be performed without applying a large external force. , deformation of the nozzle body 7, that is, deformation of the swirl chamber 9, can be prevented as much as possible. Therefore, since the nozzle body 7 can be assembled with high precision, the amount of fuel to be injected can be ensured with high precision, and the assembly can be easily performed.

In addition, in the unlikely event that the nozzle body 7 is assembled later,
Even if the nozzle body 7 is found to be defective, the retaining ring 1
6, this defective nozzle body 7
can be easily replaced with a good nozzle body 7. Therefore, the entire fuel injection valve does not become defective due to a defect in the nozzle body 7 alone, and the incidence of defective products can be significantly reduced.

Further, since the nozzle body 7 is not attached by caulking inside the tip of the nozzle tube 1, difficult caulking is not required, and the assembly can be performed even more easily.

Further, since the nozzle tube 7 is made of a non-magnetic stainless steel material, it is excellent in preventing rust.

Note that this invention is not limited to the above embodiments. For example, the driving structure of the valve stem member 20 is not limited to an electronic type, but may be a mechanical driving structure. In addition, nozzle tube 1
is not limited to non-magnetic stainless steel material, but may be made of non-magnetic material such as aluminum.

As explained above, the present invention is characterized in that the nozzle body is fitted inside the tip of the nozzle tube, and the nozzle body is detachable by means of a retaining ring.

Therefore, since there is no need to use caulking to assemble the nozzle body, the assembly can be easily performed, and the incidence of defects in the nozzle body can be reduced and the injection amount can be controlled with high precision. Furthermore, even if the nozzle body is later found to be defective, the nozzle body can be easily replaced.
This has excellent effects, such as preventing the entire injection valve from becoming defective.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Nozzle tube, 2... Inflow chamber, 7... Nozzle body, 9... Whirlpool chamber, 10... Injection passage, 18...
Valve hole, 16... retaining ring, 19... valve body.

Claims (1)

[Claims] A nozzle body having a swirl chamber is housed inside the tip of the nozzle barrel, and a fuel inflow chamber is formed inside the base end of the nozzle barrel, and an injection passage leading to the swirl chamber is opened in the inflow chamber. In the fuel injection valve, the opening is configured as a valve hole, and fuel is injected from the nozzle hole of the nozzle body by opening and closing the valve hole with a valve body. 1. A spiral fuel injection valve, characterized in that a retaining ring is fitted inside the tip of a nozzle cylinder and detachably holds the nozzle body inside the tip.