JPS63183217A - Internal combustion engine - Google Patents

Abstract

PURPOSE:To improve the ignitability and combustion efficiency of fuel through premixing fuel with air and then activating it by causing a valve for opening and closing the connection between a main combustion chamber and a fuel activation chamber to open by way of moving a valve body to the fuel activation chamber, and then placing an ignition plug in the fuel activation chamber. CONSTITUTION:When an internal combustion engine is in the compression stroke, the compressed air in a main combustion chamber 2 is injected through a compressed-air introducing hole 18a into a fuel feeding hole 18, and then introduced into a fuel activation chamber 3. In addition, fuel is injected through a fuel injection nozzle 17 into the fuel feeding hole 18, and then, it is premixed with the compressed air in the fuel feeding hole 18 before it is injected into the fuel activation chamber 3. In addition, in the neighborhood of the top dead point of compression, a valve body 10 is caused to ascend by means of a cylinder 11 so that a valve 13 is caused to open, and at the same time, a spark is generated by an ignition plug 21 placed in the fuel activation chamber 3. Thereby, a fuel-air mixture in the fuel activation chamber 3 is mixed with the compressed air in the main combustion chamber 2, and ignited to burn certainly.

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to an internal combustion engine, and more specifically, it has a fuel activation chamber in the vicinity of a main combustion chamber, and a space between the fuel activation chamber and the main combustion chamber. This invention relates to an internal combustion engine equipped with a valve that opens and closes between these parts.

b. Prior art and its problems Combustion systems for internal combustion engines, for example compression ignition engines, include direct injection, pre-combustion chamber, swirl chamber, and air chamber.

However, in both combustion methods, liquid fuel is injected directly into the combustion chamber, so before a uniform gas mixture of the injected liquid fuel and air is formed,
Compression ignition combustion may have started. In this case, unburned hydrocarbons are generated in the combustion chamber and black smoke is emitted from the compression ignition engine, thus reducing fuel efficiency and contributing to air pollution.

In addition, many of the current compression ignition engines burn at high compression ratios and high temperatures, so nitrogen oxides (Nox
) were emitted in large quantities, which also contributed to air pollution.

Therefore, in view of these circumstances, the applicant first requested the following:
We have proposed an internal combustion engine that has a fuel activation chamber near the main combustion chamber and a valve that opens and closes the space between the activation chamber and the main combustion chamber. 277908 etc.).

In these internal combustion engines, the valve has a structure in which the valve body moves from its valve seat toward the main combustion chamber to open and close. No large loss occurred, and therefore it was possible to improve the rotational speed and maximum output of the internal combustion engine.

However, as a result of further research, the applicant came up with an internal combustion engine that can further increase combustion efficiency and further improve maximum output.

That is, an object of the present invention is to provide an internal combustion engine that can further improve combustion efficiency and maximum output.

Means for Solving the C0 Problem In order to achieve the above object, the present invention has a fuel activation chamber in the vicinity of the main combustion chamber, and a space between the fuel activation chamber and the main combustion chamber. In an internal combustion engine equipped with a valve that opens and closes, the valve is configured to be opened by moving its valve body toward the fuel activation chamber, and the spark plug is configured to face the fuel activation chamber.

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 to 4 show an embodiment of the present invention.

The internal combustion engine 1 of this embodiment is a case where the present invention is applied to a compression ignition engine such as a diesel engine.

The internal combustion engine 1 has a fuel activation chamber 3 in the upper vicinity of the main combustion chamber 2 thereof.

The fuel activation chamber 3 is formed in a lower part 4b of a cylindrical holder 4 with a stepped portion 4C, in which an upper part 4a is formed with a small diameter and a lower part 4b is formed with a relatively large diameter.

The fuel activation chamber 3 is formed in the shape of a rotating body centered on the vertical axis of the holder 4, and in particular, its upper portion is formed in a conical shape.

Further, the holder 4 is formed with a substantially semi-spherical recess 5 opening downward below the fuel activation chamber 3 .

Corresponding to this depression 5, a substantially semispherical depression 7 opening upward is also formed in the upper part of the piston 6.

When the main combustion chamber 2 is at its compression top dead center, the depression 5 and the depression 7 form a substantially spherical shape in which swirl A is likely to occur, except for the flat plate-shaped portion between the piston and the cylinder head 8. .

The upper part 4a of the holder 4 has a communication hole 9 extending in its axial direction.
is formed.

A rod 11 having a valve body IO at its lower part is inserted into the insertion hole 9 so as to be slidable and to form a seal between the rod 11 and the holder 4 .

The valve body IO is provided with a holder 4 between the fuel activation chamber 3 and the recess 5.
A valve 13 is configured together with a valve seat 12 formed in the above.

A spring 15 is interposed between the tappet 14 fixed to the upper end of the port 7 and the cylinder head 8.

The valve body 10 is constantly urged upward by the elastic force of the spring 15, and is moved up and down as the cam 16 in contact with the tappet 14 rotates.

The cam 16 is rotated at a predetermined timing by receiving power from a crankshaft (not shown) via a power transmission means (not shown).

Therefore, the valve 13 is opened and closed at predetermined timing by the rotation of the cam 16.

The opening period of the valve 13 is preferably an appropriate period from around the end of the compression process to around the beginning of the exhaust process, but is not particularly limited to this. For example, the opening period of the valve 13 can be a long period from around the end of the compression process to around the end of the suction process.

Further, the opening timing of the valve 13 is preferably configured to be advanced in accordance with the rotational speed of the internal combustion engine.

Note that this advancing device can be easily constructed and installed in the above-mentioned power transmission means using conventional technology, so a detailed explanation thereof will be omitted.

Furthermore, a fuel supply hole 18 is formed in the side of the holder 4 for guiding and supplying the injected fuel from the fuel injection nozzle 17 into the fuel activation chamber 3 .

This fuel supply hole 18 is preferably formed eccentrically with respect to the fuel activation chamber 3 (see FIG. 2), so that the injected fuel from the fuel injection nozzle 17 is directed clockwise in FIG. Swirl B is formed. This swirl B
This promotes fuel activation.

Further, the fuel supply hole 18 of the holder 4 and the recess 5 are communicated with each other through a small diameter compressed air introduction hole 18a.

This compressed air introduction hole 18a guides compressed air within the main combustion chamber 2 into the fuel supply hole 18. The compressed air from this compressed air introduction hole 18a is transferred to the fuel injection nozzle 17.
The fuel is premixed with the fuel injected from the fuel chamber 3 and is injected into the fuel activation chamber 3.

In this way, the fuel supply hole 1B serves to mix fuel and compressed air in advance and send the mixture to the fuel activation chamber 3, so it forms a so-called pre-mixing port for the fuel activation chamber 3.

Furthermore, the tip of the glow plug 19 faces the fuel activation chamber 3 in a slightly protruding manner. The glow plug 19 is preferably arranged slightly downstream from the hole 18 in the direction of fuel injection.

Furthermore, a female screw hole 20 is formed on the side of the holder 4 facing the fuel supply hole 18. In the female screw hole 20,
Spark plug 21 is fastened. The spark plug 21 is
1, so as not to disturb the swirl B in the fuel activation chamber 3.
Although the distal end portion 21a is located within the female screw hole 20, it is of course possible to install the distal end portion 21a so as to protrude from the female screw hole 20.

The spark plug 21 is inserted into the female thread 2 through a hole 22 formed in the cylinder head 8 corresponding to the female thread hole 20 of the holder 4.
It is removably fixed to 0.

Furthermore, another hole 23 is formed in the holder 4, and holes 24, 25 are formed in the cylinder head 8, corresponding to the wire holes. The hole 23 is formed facing downstream with respect to the swirl B in the fuel activation chamber 3 .

The hole 25 communicates the hole 24 with the main combustion chamber 2 . The fuel activation chamber 3 thus communicates with the main combustion chamber 2 via the holes 23, 24, 25.

Further, between the holes 24 and 25, there is an air Wm adjustment device 2 configured to change the degree of opening of the hole 25 with respect to the hole 24.
6 is installed interveningly.

This air amount adjusting device 26 consists of a small cylindrical rod 27 having an inclined portion 27a at its tip, and a rotating means 28 for appropriately rotating the rod.

The small rod 27 is rotatably supported in a hole 29 formed in the cylinder rod 8, with its inclined portion 27a disposed above the mouth of the hole 25.

The small rod 27 is connected to a rotating means 28 via a connecting rod 30. This is provided to supplement the amount of compressed air sent from the main combustion chamber 2 to the fuel activation chamber 3 via the compressed air introduction hole 18a by detecting that the small loft 27 is By rotating the opening of the hole 25, the inclined portion 27a overlaps with the opening of the hole 25 to narrow the opening and adjust the amount of compressed air flowing through the holes 25, 24, and 23.

The rotation means 28 may be configured to, for example, change the number of rotations of a crankshaft (not shown), the amount of depression of an accelerator pedal, the degree of change in the amount of depression of an accelerator pedal, or the degree of change of flow velocity on the downstream side of a throttle valve in an intake pipe (not shown). The small rod 27 is rotated by an appropriate amount based on.

This rotation means 28 includes, for example, a processing device such as a microcomputer that processes detection data obtained by detecting various changes as described above, a stepping motor that is driven as appropriate based on the processing results of the processing device, and the like. It may be configured by a reduction gear or the like, or it may be configured by being mechanically connected directly to a throttle valve or an accelerator pedal, etc. via a connecting means (not shown). The configuration may be appropriately determined in consideration of the purpose of use and the like.

Further, the upper surface 10a of the valve body 10 is formed in a conical shape similarly to the ceiling surface 3a of the fuel activation chamber 3. Thereby, when the valve body 10 is moved upward and comes into contact with the ceiling surface 3a, the space between the valve body 10 and the cylinder head 8 is completely sealed.

Further, two annular grooves 31 are formed on the upper surface 10a of the valve body 10, and two annular grooves 31 are formed on the side peripheral surface 10b.
2 is formed. Note that the number of these grooves 31 and 32 is not particularly limited.
During operation of the valve 13, carbon adhering to the upper surface 10a and/or ceiling surface 3a of the valve body 10 is efficiently peeled off, and carbon adhering to the side peripheral surface 10b of the valve body 10 and/or the valve seat 12 is also removed. Efficiently peeled off. especially,
By being able to peel off the carbon between the upper surface 10a of the valve body 10 and the ceiling surface 3a, good sealing between the valve body 10 and the cylinder head 8 can be maintained at all times when the valve body 10 is moved upward. .

Further, as described above, the holder 4 has an annular stepped portion 4c between its upper portion 4a and lower portion 4b. Corresponding to the shape of this holder 4, a small diameter hole 8a and a large diameter hole 8b are formed in the cylinder head 8, and a hole 8a and a hole 8b are formed.
An annular step portion 8c is formed between the two.

In this embodiment, the hole 8b is formed largely eccentrically with respect to the main combustion chamber 2 so that a portion of the hole 8b overlaps the cylinder liner 34 fixed to the inner circumferential surface of the cylinder block 33. There is.

Here, attachment of the holder 4 will be explained.

The holder 4 has a hole 8 a + from below the cylinder head 8.
8b and is fixed to the cylinder and integrated with the Rad 8. At this time, the stepped portion 4c of the holder 4 and the stepped portion 8c of the cylinder head 8 are brought into close contact. After tightening, this cylinder head is fixed to the cylinder block 33. As a result, the vertical movement of the holder 4 is restricted by the stepped portion 8c of the cylinder head 8 that presses the stepped portion 4c, and the upper end surface 34a of the liner 34 that presses a portion of the bottom surface 4dΦ, and the holder 4 is completely Fixed.

It is preferable that the holder 4 is prevented from rotating relative to the cylinder head 8 by a rotation locking key (not shown) at some point. In this case, there is no rotation relative to the cylinder head 8, so the locking key is not needed in this case.

Further, as a fixed position of the holder 4, a part of the bottom surface 4d of the holder 4 is fixed to the cylinder block 33 far beyond the liner 34.
Of course, it is also possible to reach this point.

Furthermore, in this embodiment, two guide grooves 35 are formed that extend linearly or curvedly from the recess 7 of the piston 6. Note that the number of guide grooves 35 is not particularly limited either. This groove 35 effectively causes the air in the main combustion chamber 2 to swirl during the compression process. therefore,
When the guide groove 35 is formed in a curved shape, it is preferable to make it coincide with the direction of the swirl. In FIG. 4, circles 36 and 37 indicated by dotted lines on the piston 6 indicate the installation positions of intake valves and exhaust valves (not shown) provided on the cylinder head 8 with respect to the piston 6.

Next, the operation of this embodiment will be explained.

When the internal combustion engine 1 is currently in a compression process, the air within the main combustion chamber 2 is compressed. Then, the compressed air in the main combustion chamber 2 is injected into the fuel supply hole 18 through the compressed air introduction hole 18a, and guided into the fuel activation chamber 3 through the fuel supply hole. Also, at this time, fuel is injected from the fuel injection nozzle 8 into the fuel supply hole 18 . This injected fuel is
The compressed air introduced from the main combustion chamber 2 through the compressed air introduction hole 18a is mixed in advance in the fuel supply hole 18, and then injected into the fuel activation chamber 3. Due to this ejection, the fuel activation chamber 3
Swirl B is formed within the fuel, and activation of the injected fuel is promoted. At the same time, the injected fuel is heated by the glow plug 19 to promote its activation and form a uniform air-fuel mixture.

Next, due to the rotation of the cam 16, the valve 10 is moved upward near the compression top dead center, and the valve 13 is opened. At the same time, a spark is emitted by the spark plug 21 at a predetermined ignition timing. By opening the valve 10, the fuel activation chamber 3
The air-fuel mixture in the main combustion chamber 2 mixes with the compressed air in the main combustion chamber 2 and begins to ignite and burn, and is further reliably ignited by the spark from the ignition plug 19. Due to this ignition, the air-fuel mixture in the fuel activation chamber 3 begins to burn and its pressure is rapidly increased, and the space between the valve body 10 and the valve seat 12 and the hole 18.
It is injected into the main combustion chamber 2 via 18a. At this time,
In particular, due to the combustion mixture injected through the hole 18a,
A strong swirl is formed within the main combustion chamber 2.

Due to this swirl, combustion within the main combustion chamber 2 is performed smoothly.

Furthermore, as described above, when the valve 13 is opened and combustion begins, the valve body 1O comes into contact with the ceiling surface 3a to seal between the valve body and the cylinder head 8. This seal allows the combustion mixture in the fuel activation chamber 3 to flow between the holder 4 and the cylinder head 8.
This prevents leakage to the outside through the gap between the

Thereafter, the valve 13 is closed at an appropriate time, such as near the end of the expansion stroke or near the end of the exhaust stroke. Thereafter, the same operations as described above are repeated.

Note that the internal combustion engine l of the above embodiment includes an air amount adjusting device 2.
6, or in addition thereto, a compressed air supply means 38 may be additionally installed to supply compressed air into the fuel activation chamber 3 during acceleration of the internal combustion engine.

As shown in FIG. 1 as an example, this compressed air supply means 38 includes a pump 39 that compresses a part of clean air obtained through an air cleaner or the like, and a pump 39 that stores the air compressed by the pump. A tank 40, a conduit 41 that guides compressed air from the tank to the fuel activation chamber 3, a normally closed solenoid valve 42 interposed in the middle of the conduit 41, and the solenoid valve 42.
It can be composed of a solenoid valve control section 43, etc., which controls the opening and closing of the valve as appropriate.

The pump 39 is driven by power transmitted from a crankshaft (not shown).

The solenoid valve control unit 43 opens the solenoid valve 42 to open the fuel activation chamber 3 when the internal combustion engine is being accelerated (hereinafter referred to as acceleration time) or when a load is applied to the internal combustion engine (hereinafter referred to as Kaga loading time). It is operated to send compressed air to.

In this example, by utilizing the fact that the control rack 44a of the fuel supply pump 44 is largely moved to one side when the internal combustion engine is accelerated or under load, the actuator of the switch 45 is pressed by the operation of the control rack 44a, and the actuator of the switch 45 is pressed. The switch is opened, thereby allowing operating current to flow from the battery 46 to the solenoid valve 42 via the switch 45.

In addition, 47 is a check valve interposed in the middle of the conduit 48 connecting the pump 39 and the tank 40 to prevent the compressed air from flowing back from the tank 40 to the pump 39 side, and 49 is a check valve that prevents the compressed air from flowing back from the tank 40 to the pump 39 side. This is a relief valve to maintain a constant value.

Furthermore, when installing the compressed air supply means 38, compressed air may be directly supplied to the fuel activation chamber 3 as shown in FIG. It is preferable to supply the fuel so that it is ejected in the same direction as B and in the tangential direction, for example, from the hole 23 or the fuel supply hole 1B, or from any point between the hole 23 and the fuel supply hole 18. It is better to supply it from

Next, let's summarize the characteristic actions of the internal combustion engine:
It is as follows.

l) Early activation of the injected fuel The fuel is injected into the fuel activation chamber 3 which contains high-temperature residual gas from the fuel injection nozzle 17 and has a wall surface heated to a high temperature.
The compressed air introduction hole 18
It flows in from a, is premixed with compressed air, and further swirls in the fuel activation chamber 3 and is forcibly preheated by the residual gas, the hot wall surface, the glow plug 19, etc., to form a uniform air-fuel mixture. Note that if the compressed air introduction hole 18a is made too large, self-ignition will occur in the fuel activation chamber 3, resulting in so-called diesel combustion, so it is preferable to set the diameter of the compressed air introduction hole 18a relatively small.

2) Control of ignition timing by spark plug 21 and valve 4 Valve body lO of valve 13 provided near fuel activation chamber 3
The uniformly activated (premixed, preheated) air-fuel mixture between the upper surface 10a of the valve element IO and the ceiling surface 3a of the fuel activation chamber 3 can be moved between the upper surface 10a of the valve element IO and the ceiling surface 3a of the fuel activation chamber 3 by pulling up the valve element IO. A squish action is applied by the surface 3a, and the air is violently injected into the main combustion chamber 2 from the opened valve 13, and is further activated when it comes into contact with fresh air in the main combustion chamber, and as the valve 13 is opened, a spark is generated from the ignition plug 21. is released and burns immediately. Note that in this internal combustion engine, ignition combustion can essentially be performed by opening the valve 13 without relying on the spark of the ignition plug 21, so the ignition plug 21 can be omitted.

Furthermore, in the case of a configuration using the ignition plug 21, even if fuel that is difficult to activate or ignite is used, it is possible to reliably ignite it at a predetermined timing.

Therefore, whether or not to adopt a configuration using the spark plug 21 can be determined as appropriate by considering the type of fuel, its properties, the purpose of use of the internal combustion engine, and the like.

As is clear from the above, in the internal combustion engine, the ignition timing can be optimally controlled by appropriately selecting and changing the opening/closing timing of the valve 13 and the spark timing of the ignition plug 21.

In addition, when the configuration is such that ignition is performed by the spark of the ignition plug 21, the timing at which the spark from the ignition plug 21 is emitted is preferably set to coincide with the opening timing of the valve I3.

In addition, since the opening and closing timing of the valve IO can be controlled, the fuel supply time can also be controlled, so that the fuel and air can be premixed and preheated and activated in advance in the fuel activation chamber 3. Fuel can be gasified in an optimal state suitable for various internal combustion engines. Therefore, it is possible to use a wide variety of fuels and to apply it to all internal combustion engines (including not only diesel engines but also ordinary gasoline engines).

3) Quiet premixed combustion can be achieved without causing the diesel knock that is characteristic of premixed combustion diesel combustion due to activation, and there is little exhaust gas, and in particular, almost no black smoke is seen. Therefore, high speed rotation is possible and the compression ratio can be lowered slightly, so it is expected that the weight of the engine will be reduced. Furthermore, since the excess air ratio can be brought close to 1.0, it is also possible to improve the output.

In the present invention, the holder 4 may of course be installed at the center of the piston 6.

Further, the shape of the recess 7 of the piston 6 is not limited to a substantially hemispherical shape, but may be any shape such as a substantially cylindrical shape.

Furthermore, the grooves 31 and 32 of the valve body 10, the air m adjustment device 26
, 135 of the piston 6, and the compressed air supply means 38 may be omitted, or may be added selectively and appropriately in consideration of the intended use of the internal combustion engine 1.

Furthermore, it is preferable to form at least the wall surface surrounding the fuel activation chamber 3 or the entire holder 4 using a ceramic material, since this can improve the thermal efficiency of the internal combustion engine. Of course, the cylinder head 8 and cylinder block 33
In addition, the entire structure may be formed from a ceramic material.

e. As described in detail, according to the internal combustion engine of the present invention, fuel can be premixed and activated in the fuel activation chamber under high pressure and high temperature, and moreover, Since it can be ignited using a spark plug, combustion efficiency can be increased compared to conventional internal combustion engines, especially compression ignition engines, even when the compression ratio is higher or lower. For this reason, black smoke,
Nitrogen oxides (Nox) can be reduced, and therefore, air pollution caused by black smoke and nitrogen oxide emissions can be prevented. Furthermore, it is possible to prevent the occurrence of diesel fuel, etc., and to improve acceleration performance while preventing the emission of a large amount of black smoke during acceleration or during loading.

Furthermore, since the present invention is configured to ignite using a spark plug, the fuel injected from the fuel injection nozzle can be reliably combusted, so many types of fuel can be used. Even if the amount is set to a small value, smooth combustion can be achieved, and therefore,
Fuel efficiency can be improved.

[Brief explanation of the drawing]

1 to 4 show an embodiment of a piston structure for an internal combustion engine according to the present invention, FIG. 1 is a conceptual sectional view thereof, FIG. 2 is an enlarged sectional view of the main parts, and FIG. The figure is an enlarged sectional view of the main part, and FIG. 4 is a plan view showing the piston structure. 1... Internal combustion engine, 2... Main combustion chamber, 3...
・Fuel activation chamber, 4... holder, 4c... stepped portion,
5... recess, 6... piston,
7... Recess, 8... Cylinder head, 8c.
...Stepped portion, 10...Valve body, 11...Rod, 12...Valve seat, 13...Valve, 14...
...Tappet, 15...Spring, 16...
・Cam, 17...Fuel injection nozzle, 18,
18a...hole, 19...glow plug, 20
...Female screw hole, 21...Spark plug, 22.
...hole, 23.24.25...hole, 26
...Air amount adjustment device, 27...Small rod, 27a.
... Inclined portion, 28... Rotating means, 31, 32.
...Groove, 33...Cylinder block, 34.
...liner, 35...guide groove. ' Figure 2 Figure 3 Procedures Written and sealed by Chief Ho Masaru) November 13, 1985 Mr. Kunio Ogawa, Commissioner of the Japan Patent Office.
-Go to 9-7- Relationship to the case Patent applicant name Haruyama Giken Co., Ltd. 4, agent 107 Address 3-2-3-5 Akasaka, Minato-ku, Tokyo "Details of the invention" in the specification to be amended "Explanation" column. 6. Contents of the amendment As shown in the attached sheet, contents of the amendment 1) The following sentence is inserted between page 17, line 14 and line 15 of the specification of the present application. Note that the internal combustion engine 1 may be configured to include a valve control means (not shown) that opens and closes the valve 13 at the ignition timing when rotating at low speeds, and keeps it open when rotating at medium speeds or higher. . The valve control means is, for example, a mechanism that detects the rotation speed and stops the cam 16 to open the valve 13 when the rotation speed reaches a medium speed. Since such a mechanism can be easily constructed by using a conventionally well-known speed detection sensor, a control device using a microcomputer, etc., a detailed explanation thereof will be omitted. Note that the mechanism of this valve control means is, of course, not limited to the one described above;
Any configuration may be used as long as the valve 13 can be kept open at medium speed or higher. In the valve control means in this embodiment, the medium speed means:
Although it is preferable to set it within the range of 1500 to 2000 rpm, the present invention is not particularly limited to this, and may be determined as appropriate in consideration of the type, performance, purpose of use, etc. of the internal combustion engine to which the present invention is applied. . By using such a valve control means, non-king can be effectively prevented at low to medium speeds, and
Smooth high-speed operation can be achieved at medium to high speeds.

Claims (1)

[Claims] In an internal combustion engine having a fuel activation chamber in the vicinity of a main combustion chamber, and a valve between the fuel activation chamber and the main combustion chamber for opening and closing the space therebetween, the valve body is connected to the fuel activation chamber. An internal combustion engine characterized in that the engine is configured to be opened by being moved to the side, and the spark plug is made to face the fuel activation chamber.