JPS62129564A - Multicylinder type injection internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is characterized in that a common injection pump is provided, a blocking member is attached to each injection valve, and this blocking member connects the pressure pipe leading to the injection port. Depending on the compressive pressure in the cylinder that keeps it closed and determines the injection point, the injection orifice opens, the blocking member is formed as a plunger, and the connecting hole forms a conduit connection between the plunger working chamber and the cylinder working chamber. , the connection hole extends inside the casing of the injection valve, Japanese Patent Application No. 60-42751
Regarding the multi-cylinder internal combustion engine.

[Conventional technology]

This type of injection device has the disadvantage that, after long-term operation of the device, at least the cylinder-side region of the connection hole gradually becomes clogged with combustion residues. In this case, the flow cross section is reduced and the control function of the plunger is therefore impaired.

[Purpose of the invention]

The object of the invention is to eliminate the above-mentioned drawbacks by making it possible to clean the connecting holes simply and reliably.

[Structure of the invention]

This object is solved according to the invention in that the end of the connecting hole opposite the cylinder working chamber has an open outlet from the housing part with the connecting hole and is closed off by a closing member when the engine is running. .

〔Effect of the invention〕

If necessary, the closing member can be removed, with the injection valve installed, and the connection hole can be blown through and cleaned by compressed pressure even when the engine is running, and when the engine is stopped, the flexible A suitable tool, such as a wire, can be passed through the connection hole over its entire length to clean it. Penetrating the connection hole with a tool can be done even when the injection valve is disassembled.

[Embodiments of the invention and its effects]

According to an embodiment of the invention, it is advantageous if the closing element is designed as a threaded bolt with a sealing cone that closes off the end of the connection hole.

The provision of a threaded bolt in the casing of the injection valve in such a way that it is accessible during its disassembly and installation makes it possible to clean the connection hole in any position of the injection valve.

The cleaning of the connection hole by blowing and piercing is carried out according to another embodiment of the invention, in which the hole in the engine case, which opens into the cylinder working chamber and surrounds the end part of the injection valve, is connected to the connection hole over its entire length. This is greatly facilitated by the provision of lateral extensions extending at least approximately parallel to the axis.

〔Example〕

In the following description, embodiments of the invention will be explained based on the figures.

As described in Japanese Patent Application No. 60-42751, the individual parts 368, 372, 374 of the injection valve are fixed to each other by threaded sleeves 376 and by means not shown, for example fixing pins. It is held in its required relative angular position. In the installed state, the injection valve rests with its lower end face on a shim ring, ie an elastic packing ring 382. This shim ring is placed on the seat surface 20s of the cylinder hept 20a.

The portion 374 having the injection port 374a passes through the hole 20r and reaches into the working chamber 10aa of the cylinder IDa. This cylinder houses a piston 78.

Two threaded holes 20g (see FIG. 2) are formed in the cylinder head to secure the injection valve within the cylinder head 2Oa. Each of the holes accommodates a screwed stud bolt 400. This stud bolt 400 is also provided with a thread at its free end. The flange-shaped clamp claw 402 has two holes 4
Two stud bolts 400 are inserted into the hole 402a, and a cylindrical clamp 404 with a step is accommodated in the hole 402b in the center, and the lower surface 402c of the spherical cutout is inserted into the clamp 40.
It is on the collar 404a of No. 4. Pressure pipe 406 is part 3
The pipe 406 rests on the horizontal concave m 368q formed on the upper end surface of the portion 68 and the horizontal portion 404q formed on the lower end surface of the portion 404 (in FIG. (The exact location is shown in Figure 3). When the tightening nut 408 screwed into the stud bolt 400a is tightened, the clamp 402 is pressed against the section 404, and the pressure tube 406 is pressed against the section 404 while the pressure tube 406
and 368, and on the other hand, the entire injection valve is tightened between the seal ring 382 and the seat surface 20s of the cylinder head 20a.
be forced to.

Fuel is supplied from the storage tank to the pressure pipe 406 by an injection pump (not shown) described in Japanese Patent Application No. 60-42751. As shown in FIG. 2, this pressure tube is provided with a horizontal hole 406a. This lateral hole is connected to the hole 368a of the section 368 via a seal ring 409. The horizontal hole 368b reaches the vertical hole 368C of the portion 368,
This vertical hole opens into hole 372a in section 9372. This hole 372a is connected to a vertical hole 374b of the portion 374, which further opens into recesses 374c and 374d. Fuel flows from this recess to the injection port 374 at the end of the injection valve.
reach a. This injection port is opened and closed by the end 380a of the nozzle needle 380. Nozzle needle 380 is operated against spring 388 by fuel pressure in its shoulder ff 1380c.

The lateral hole 368b is hermetically closed at its free end by a ball 384. The upper end of hole 368C is similarly hermetically closed by pawl 386.

A control plunger 392, which is influenced by the compression pressure in the associated working chamber 10aa, is slidably supported along the axial centerline of the portion 368. control plunger 392
is provided with a notch 392a in its central range.

Control plunger 392 is pressed against upper fixed stop 396 under the action of spring 394 . spring 394
is supported by a fixed spring receiver 390. The upper end 390a of the spring receiver 390 simultaneously serves as a stop for the control plunger 392 in its lower position. The combustion pressure from the working chamber 10aa reaches the working chamber 368e through the holes 368rr, 368r, 372r, 374'' and the original chambers 376r, 2Or.

A reflux hole 404d is formed in the clamp 404, and a reflux conduit 41Qa, a threaded outlet 404g of this reflux hole,
A nipple 410 with 410b is connected. On the other hand, it opens into the hole 404d through the seal ring 412,
It leads to other pipes 410.410a and 410b.

A plurality of injection valves are connected to the pressure pipe 406 in the same manner. In the case of six valves, the connecting line leading to the injection port 374a is kept closed by an attached control planter 392, as shown in FIG. Attached cylinder working chamber 10a
As soon as the compression pressure in a reaches the level required to start the injection process, the combustion pressure acting on the upper end face of the control plunger 392 in the working chamber 368e causes the control plunger 392 to close the hole 368b. The hole 368b is moved from the closed position of FIG. 1 to the open position of FIG. 2. Second
In the position shown in the figure, fuel reaches the injection port 374a of the injection valve from the pressure pipe 406 and is injected into the cylinder working chamber 1Oaa. As soon as the compression pressure in the working chamber 368e decreases, the return spring 390 returns the control plunger 392 to the blocking position shown in FIG.

After a long period of operation, a conduit provided in the injection valve that supplies the compression pressure of the working chamber 368e is connected to the working chamber 10a.
The control plunger 39 gradually accumulates and the flow cross-sectional area changes due to coking.
This will have an adverse effect on the control function of No. 2. To eliminate this drawback, cleaning can be carried out according to the invention.

For this purpose, the hole 368r reaches the upper end of the portion 368,
During operation of the engine, the hole 20r of the cylinder head 20a is the hole 3 of the portion 374.
Lateral enlargement 20 extending coaxially or nearly coaxially with 74r
It is equipped with rr.
4° This allows the closing bolt 414 to be opened when the engine is rotating, and the connecting line 20 to be closed by compression pressure.
rr, 376r, 374r, 372r, 368r
It can be cleaned by blowing. However, this connecting line can be cleaned by inserting a suitable cleaning tool, such as a flexible wire. In this case, the coking residues fall into the working chamber 10aa of the cylinder 10a and are removed during the next combustion.

Disassemble the entire injection valve, remove the closing bolt 414,
Of course, it is also possible to clean the connecting pipe with a cleaning tool.

The oblique hole 368rr leading to the working chamber 368e is not cleaned in this embodiment. This is because coking occurs in the cylinder working chamber 1.
This is because it occurs strongly in conduits close to 0aa.

However, when it is necessary to clean the diagonal hole 368rr remote from the working chamber 10aa, it is possible to move this diagonal hole between the outer peripheries of the section 368 and close this area by means of a removable closing bolt only for cleaning purposes. can.

[Brief explanation of drawings]

Figure 1 shows the installed state of the injection valve, A-A in Figure 3.
A longitudinal cross-sectional view along the line, Figure 2 is similar to Figure 3. a partial longitudinal sectional view of the injection valve and the fixing means along line B-B;
3 is a plan view of FIG. 1, and FIG. 4 is a cross-sectional view taken along line C--C of FIG. 1.

Claims (4)

[Claims] 1. A common injection pump is provided and each injection valve is provided with a shut-off element which keeps closed the pressure line leading to the injection orifice and allows the injection to occur depending on the compression pressure in the cylinder which determines the injection point. Multi-cylinder internal combustion engine with an open mouth, in which the shut-off element is designed as a plunger, the connecting hole forms a line connection between the plunger working chamber and the cylinder working chamber, and the connecting hole extends in the casing of the injection valve. Internal combustion engine, characterized in that the end of the connecting hole opposite the cylinder working chamber has an open outlet from the casing part with the connecting hole and is closed by a closing member during operation of the engine. 2. 2. Internal combustion engine according to claim 1, characterized in that the closing element is designed as a threaded bolt with a sealing cone closing the end of the connection bore. 3. 3. Internal combustion engine according to claim 2, characterized in that a threaded bolt is provided on the casing of the injection valve so that it can be accessed during disassembly and assembly. 4. Over its entire length, a hole in the engine case opens into the cylinder working chamber and surrounds the end part of the injection valve.
2. The internal combustion engine according to claim 1, further comprising a lateral enlargement extending at least substantially parallel to the axis of the connecting hole.