JPH0553927B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to an internal combustion engine equipped with a pre-combustion chamber.

b. Prior Art In conventional internal combustion engines, such as compression ignition engines, liquid fuel is injected directly into the combustion chamber, so the injected liquid fuel is sufficiently vaporized and mixed uniformly with air. Compression ignition combustion begins before gas is formed.

As a result, combustion conditions are poor, unburned hydrocarbons are produced in the combustion chamber, and black smoke is emitted from the compression ignition engine, contributing to air pollution.

The present invention was invented in view of the above-mentioned circumstances, and its purpose is to provide an internal combustion engine that can significantly reduce black smoke and hydrocarbons contained in exhaust gas.

c Means for Solving the Problems In order to achieve the above object, the present invention includes a valve body slidably provided near the pre-combustion chamber, an activation chamber formed at one end of the valve body, and an activation chamber formed at one end of the valve body. forward movement means that is provided with a communication hole that communicates the chamber and the pre-combustion chamber, moves the valve body forward according to the ignition timing, and accordingly moves the active chamber into the pre-combustion chamber and opens it; a fuel supply means for injecting fuel into the vaporization chamber; a notch formed at a lower end of a valve seat associated with the valve body; and a notch for shifting the valve body toward the pre-combustion chamber when sudden acceleration is applied. The internal combustion engine is constructed by including a shift means.

d Embodiments Hereinafter, embodiments of the internal combustion engine according to the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 show an embodiment of a four-cycle compression ignition engine to which the present invention is applied.

This compression ignition engine 1 is composed of a cylinder section 2 and a head section 3.

A main combustion chamber 5 is formed in the cylinder body 4 of the cylinder part 2, and a head body 6 of the head part 3 is formed.
A pre-combustion chamber 7 is formed therein.

The main combustion chamber 5 and the pre-combustion chamber 7 are communicated with each other via an ejection hole 8 formed at an angle in the head body 6.

Note that the pre-combustion chamber 7 has a substantially circular cross section so that swirl is likely to occur.

The head body 6 is provided with an opening 9, into which a substantially cylindrical valve body 10a is slidably fitted.

A vaporization valve 10 is formed by the valve body 10a and the lower end (valve seat) 10b of the opening 9 of the head body 6.

Further, the valve body 10a is guided in the vertical direction by a cylindrical sleeve 11 fitted between the valve body and the upper part of the head body 6.

An annular activation chamber 12 is formed around the lower end of the valve body 10a.
is formed.

Seal members 13, 13 are provided at the center of the valve body 10a.
is installed.

A communication hole 14 that communicates the activation chamber 12 and the pre-combustion chamber 7 is bored in the lower end of the valve body 10a.

Further, a cavity 15 is formed in the upper part of the valve body 10a.

This empty chamber 15 serves to prevent heat from moving to the upper part of the valve body 10a, so the activation chamber 1 at the lower part thereof
The surrounding area of 2 is kept at high temperature.

A large diameter circular plate 16 is fixed to the upper end of the valve body 10a, and a spring 17 is interposed between the plate and the upper end surface of the head body 6.

The valve body 10a is always urged upward by a spring 17, thereby sealing the activation chamber 12.

Furthermore, a wedge-shaped notch 9a is formed at the lowest part of the lower end portion 10b of the opening 9, facing the pre-combustion chamber 7.

The number and size of the notches 9a are not particularly limited, and may be appropriately determined in consideration of the size of the active chamber 12, etc.

A fuel injection nozzle 18 is disposed within the head body 6 so as to face the activation chamber 12.

Further, the head main body 6 is provided with a shifting means 19 for the valve body 10a.

The shift means 19 includes a bypass passage 20 branched from a lubricating oil main passage (not shown) that supplies lubricating oil to each part of the engine 1, and a bypass passage 20.
A passage 20 further branched within the head body 6
a, 21, a valve 22 interposed in the passage 20a,
A valve opening/closing control means 24 that controls the opening and closing of the valve 22 based on changes in the pressure in the intake pipe 23, a cam (reciprocating means) 25 for moving the valve body 10a up and down, and one end 26a attached to the plate body 16. Handed arm 26
and a fulcrum vertical movement means 27 for vertically moving the arm using the other end portion 26b as a fulcrum.

The passage 20a communicates with, for example, a crank chamber 28 and the like.

The passage 21 communicates with a chamber 31 surrounded by the cylinder 29 and piston 30 of the fulcrum vertical movement means 27 and the head body 6.

The valve 22 is connected to a piston 32 of the valve opening/closing control means 24.
The tip (valve body) 33 of the rod 33 extended from
a, and a bent portion (valve seat) 20b that is formed by bending the passage 20a at a substantially right angle.

The piston 32 is slidably disposed within the cylinder 34, and is always held against the head body 6 by a spring 35 interposed between the piston 32 and the end wall 34a of the cylinder.
It is forced to the side. This allows the valve 22
is considered a normally closed valve.

Further, a chamber 36 surrounded by the piston 32 and the cylinder 34 is communicated via a conduit 37 to the downstream side of the intake pipe 23 near the throttle valve 38 .

On the other hand, in the fulcrum vertical movement means 27, the fulcrum 26b of the arm 26 is rotatably supported by a rod 39 extending upward from the piston 30 by, for example, ball joint means. 40
is a nut adjuster that adjusts the height of the other end 26b of the arm 26.

A cam receiving member 41 is installed in the center of the arm 26, and the cam receiving member 41 is in contact with the cam 25.

The rotational power of the crankshaft 42 is transmitted to the cam 25 via a power transmission means (not shown), and the cam 25 is rotated at a predetermined ignition timing.

The shape of the cam 25 is appropriately determined so as to open the vaporization valve 10 before the compression process ends, and is not particularly limited.

In addition, in FIG. 1, 43 is a piston, 44
4 is an intake valve; 45 is an exhaust pipe; 46 is an exhaust valve; in FIG. 2, 47 is a stopper for the piston 30 fitted near the opening of the cylinder 29;
8 is an orifice installed downstream of the valve 22 in the passage 20a.

Next, the operation of this compression ignition engine 1 will be explained.
When the engine 1 is normally operated at a constant speed, the negative pressure generated in the intake pipe 23 acts on the piston 32 through the conduit 37, and the piston 32 moves against the elasticity of the spring 35. End wall 34a
moved to the side. This keeps the valve 22 open.

When the valve 22 is opened, the lubricating oil that is pressure-fed through the bypass passage 20 is hardly sent into the chamber 31, and passes through the passage 20a side to the crank chamber 2.
Flows to 8.

Therefore, in this normal operating state, the lubricating oil flowing through the bypass passage 20 hardly exerts any force on the piston 30, so the piston 30 is located at the lowest point.

As a result, the other end 26b of the arm 26 is positioned at the lowest point, and the valve body 10 is accordingly pushed up by the spring 17 and positioned at the highest point.

Next, explanations will be added along with each process of the engine 1.

The intake stroke and exhaust stroke in the engine 1 are performed by opening and closing the intake valve 44 and the exhaust valve 46 at predetermined timings as in the conventional engine, so a detailed explanation thereof will be omitted, and only the compression stroke and expansion stroke will be described. explain.

This engine has a crank angle of 180° to 360° (compression process)
, the piston 43 compresses the air in the main combustion chamber 5, and this compressed air is rapidly injected into the pre-combustion chamber 7 through the injection hole 8 to create a swirl within the pre-combustion chamber. Form.

Further, a part of the air ejected into the pre-combustion chamber 7 is further ejected into the activation chamber 12 via the communication hole 14.

On the other hand, fuel is supplied to the activation chamber 12 from a fuel injection nozzle 18 . The supplied fuel comes into contact with the air injected into the activation chamber 12 from the prefuel chamber 7 as described above, and is rapidly premixed and activated.

Note that the fuel injection by the fuel injection nozzle 18 is as follows:
It is preferable that this is carried out 60° to 30° before compression top dead center (before the start of ignition).

Then, just before the compression top dead center is reached, the center portion of the arm 26 is pushed downward by the cam 25. At this time, one end 26a of the arm 26 is connected to the other end 26a.
It is moved downward centering on 6b, and as a result,
The valve body 10a is also moved down.

This downward movement of the valve body 10a causes the vaporization valve 10
is opened, the activation chamber 12 is opened into the pre-combustion chamber 7, and the pre-mixture generated by being activated in advance in the activation chamber 12 rides on the swirl in the pre-combustion chamber 7 and enters the pre-combustion chamber 7. It is diffused and pre-combusted, and then the ejection port 8
It is violently ejected into the main combustion chamber 5 through the.

As a result, combustion of the compressed air in the main combustion chamber 5 starts near the compression top dead center.

Then, near the end of combustion (near the crank angle of 540 degrees), the vaporization valve 10 is closed again by the valve body 10a being moved upward by the cooperative action of the cam 25 and the spring 17. As a result, the combustion process ends and the exhaust process begins.

Next, a case where the engine 1 is suddenly accelerated will be described.

In this case, the opening degree of the throttle valve 38 is suddenly increased. At this moment, throttle valve 38
Immediately after, the negative pressure suddenly decreases instantaneously. This sudden decrease in negative pressure is transmitted to the chamber 36 via the conduit 37, whereby the pressure inside the chamber 36 is also suddenly increased, and the piston 32 is urged toward the head body 6 by the spring 35. Valve 22 is closed.

By closing the valve 22, the lubricating oil forced through the bypass passage 20 exerts a force on the piston 30, causing the piston 30 to move upward.

As a result, the other end 26b of the arm 26 is moved upward, and the one end 26b is moved upward using the point where the cam 25 and the cam receiving member 41 come into contact as a fulcrum.
6a is moved downward, and accordingly, the valve body 10a is shifted downward.

When the valve body 10a is shifted downward in this manner, the activation chamber 12 opens into the notch 9a at its lower part.

Therefore, at this time, the active chamber 12 is connected to the communication hole 1.
4 and communicates with the pre-combustion chamber 7 via a notch 9a. In this state, the communication hole 14 has the same effect as if it were made wider by the amount of communication through the notch 9a.

As a result, the communication hole 14 enters the active chamber 12.
A large amount of air can be sent from the pre-combustion chamber 7 instantly through the notch 9a. Therefore, even if a large amount of fuel is instantaneously supplied into the activation chamber 12 from the fuel injection nozzle 18 during sudden acceleration, there will be no shortage of air, and this large amount of fuel will be sufficiently activated.

Note that even in the state in which the valve body 10a is shifted downward in this manner, the vaporization valve 10 is operated in the same manner as in the case of the normal movement described above.

The shift means in the present invention is not limited to the above-mentioned embodiment, and for example, the shift means is designed to electrically detect that the throttle valve is rapidly rotated and electromagnetically shift the valve body toward the pre-combustion chamber side. These can be easily constructed using conventional techniques. In short, any configuration may be used as long as the valve body can be slightly shifted toward the pre-combustion chamber side during sudden acceleration.

The internal combustion engine to which the present invention is applied is not limited to a compression ignition engine typified by a diesel engine as in the above embodiment, but may also be a direct injection type compression ignition engine such as a gasoline engine (an Otto cycle engine). Of course, the present invention can also be applied to engines that do not have a pre-combustion chamber.

e Effects of the Invention As explained above, according to the internal combustion engine according to the present invention, the active chamber and the precombustion chamber are separated by shifting the valve body of the vaporization valve toward the precombustion chamber during sudden acceleration. Since the structure allows the cross-sectional area of the communicating air passage to be substantially changed, even if a large amount of fuel is supplied into the activation chamber during sudden acceleration, a sufficient amount of air can be supplied to compensate for the large amount of fuel supplied into the activation chamber. By effectively premixing and activating fuel, it can be combusted, and black smoke and hydrocarbons contained in exhaust gas can be significantly reduced.

[Brief explanation of the drawing]

1 and 2 show an embodiment of an internal combustion engine according to the present invention, FIG. 1 is a conceptual view of the engine, and FIG. 2 is an enlarged vertical cross-sectional view of the main parts thereof. be. 1... Internal condensation ignition engine, 2... Cylinder section, 3...
...Head part, 4...Cylinder body, 5...Main combustion chamber, 6...Head body, 7...Pre-combustion chamber, 8...
Spout hole, 9...opening, 9a...notch, 10...
Vaporization formation valve, 10a... Valve body, 11... Cylindrical sleeve, 12... Active chamber, 14... Communication hole, 15...
...Vacancy, 16...Plate, 17...Spring, 1
8... Fuel injection nozzle, 19... Shift means, 2
0... Bypass passage, 20a, 21... Passage, 2
0b...Bending portion, 22...Valve, 23...Intake pipe,
24... Valve opening/closing means, 25... Cam, 26... Arm, 26a... One end, 26b... Other end, 2
7... Fulcrum vertical movement means, 28... Crank chamber, 2
9...Cylinder, 30...Piston, 31...
Chamber, 32... Piston, 33... Rod, 33a
... Valve body, 34 ... Cylinder, 34a ... Cylinder end wall, 35 ... Spring, 36 ... Chamber, 37
... Conduit, 38 ... Throttle valve, 39 ...
Rod, 40... Asia star nut, 41...
Cam receiving member, 42...Crankshaft, 43
...Piston, 44...Intake valve, 45...Exhaust pipe, 46...Exhaust valve.

Claims (1)

[Claims] 1. A valve body slidably provided in the vicinity of the pre-combustion chamber, an activation chamber formed at one end of the valve body, a communication hole that communicates the activation chamber with the pre-combustion chamber, and a valve body provided at an ignition timing. a reciprocating means for moving the active chamber forward in response to the pre-combustion chamber and opening the active chamber; a fuel supply means for injecting fuel into the active chamber; and a valve associated with the valve body. An internal combustion engine comprising: a notch formed in a lower end of the seat; and a shift means for shifting the valve body toward the pre-combustion chamber during sudden acceleration.