JPH10121920A - Four-cycle engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase power and economize fuel in four cycle engine. SOLUTION: In a four cycle engine 1 which has strokes of intake, compression, explosion and exhaust, an auxiliary exhaust port 11 is arranged on a cylinder a wall 2a located around a lower dead center in a piston 3. The auxiliary exhaust port 11 is so designed as to open for exhausting gas just before the piston 3 reaches the lower dead center in an explosion stroke, while closing to hold the intake-air just before the piston 3 reaches the lower dead center in an intake stroke. By this constitution, an exhaust function is increased to heighten power, and also fuel is economized due to the improvement of the intake/exhaust timing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a four-cycle engine which is improved so as to enhance exhaust capacity to increase power and save fuel.

[0002]

2. Description of the Related Art The following method is known as a means for powering up a four-cycle engine. 1. Increase the intake and exhaust valves. Alternatively, the number of intakes and exhausts per hour is increased by increasing the number. 2. The intake pressure is increased by increasing the intake pressure by using a turbo or supercharger.

[0003]

However, the conventional power-up system has the following disadvantages. 1. The area of the cylinder head is limited, and the size of the valve is naturally limited even if a multi-valve structure is achieved, and it cannot be set to a necessary and sufficient size.

[0004] 2. Increasing the suction efficiency or increasing the amount of intake air by pressurizing increases the amount of exhaust gas after combustion, but the method of discharging exhaust gas from the cylinder remains the method based on the conventional exhaust valve. , The exhaust gas cannot be exhausted efficiently and the exhaust cannot catch up.

[0005] 3. Because the exhaust gas could not catch up, despite the high pressure gas during combustion (expanding) pushing down the piston and converting it to power, it was interrupted and the exhaust valve was opened at an early timing ignoring efficiency, Discharge (decompression)
If you don't start, you can't make it. For this reason, power and energy are greatly lost. SUMMARY OF THE INVENTION An object of the present invention is to solve the problem that the power-up is limited because the exhaust cannot catch up with the power-up method by increasing the intake air amount.

[0006]

The technical means proposed by the present inventors for increasing power and saving fuel in a four-stroke engine is as follows.

[0007] 1. In a four-stroke engine including an intake, compression, explosion, and exhaust strokes, an auxiliary exhaust port is provided in a cylinder wall, which is opened immediately before the piston reaches a lower dead center. A four-stroke engine with increased power by opening the valve just before the engine reaches and performing auxiliary exhaust from it, and closing the piston just before it reaches the bottom dead center in the intake stroke so that the intake air will not escape. .

[0008] 2. The auxiliary exhaust valve is attached to the auxiliary exhaust port, and the auxiliary exhaust valve is provided with control means for controlling to be open during the explosion stroke and closed during the suction stroke. Cycle engine. 3. 3. The four-stroke engine according to claim 2, wherein the auxiliary exhaust valve is opened and closed by a balance between an internal pressure in the cylinder and a spring. 4. 3. The four-stroke engine according to claim 2, wherein the auxiliary exhaust valve opens and closes based on a balance between an internal pressure in the cylinder and an elastic force of the valve itself.

[0009] 5. 3. The four-stroke engine according to claim 2, wherein the opening and closing of the auxiliary exhaust valve is controlled by a cam. 6. 3. The four-stroke engine according to claim 2, wherein the opening and closing of the auxiliary exhaust valve is controlled by a rotary valve. 7. 3. The four-stroke engine according to claim 2, wherein the opening and closing of the auxiliary exhaust valve is controlled by a slide valve.

[0010]

The auxiliary exhaust port is opened immediately before the piston reaches the lower dead center during the power stroke. For this reason, in the final stage of the explosion stroke, exhaust is performed from the cylinder via the auxiliary exhaust port, and when the piston moves to the exhaust stroke past the lower dead center, the auxiliary exhaust port is closed by the piston, and the exhaust valve is normally closed. Exhaust is performed.

In the above operation, the exhaust valve is opened later than the conventional timing, that is, at the time when the piston reaches the lower dead center, and is opened just before reaching the lower dead center to start the exhaust as in the conventional case. Do not. This is to prevent the loss of power by securing the pressure in the cylinder to the lower dead center during the explosion stroke.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of a four-stroke engine according to the present invention is the same as that of the conventional example. However, when the present invention is implemented including an engine incorporating a power-up means, it is more effective to combine the engine with the power-up means and put it into practical use.

It is desirable that an auxiliary exhaust port, which is opened at a lower portion of the cylinder immediately before reaching a lower dead center of the piston, is as close as possible to the lower dead center. For this reason, in order to secure a sufficient exhaust amount (opening area), it is practical to use a means for opening the auxiliary exhaust port in a slit shape in the circumferential direction of the cylinder. However, the opening area of each exhaust port may be reduced, and a plurality of auxiliary exhaust ports may be provided instead to secure a sufficient exhaust amount. For this reason, in the present invention,
The shape and number of the exhaust ports are not particularly limited.

The auxiliary exhaust port is closed by the piston until immediately before the piston reaches the bottom dead center. However, in the auxiliary exhaust port, there is a mechanical means using a cam, a rotary valve, a slide valve, or the like by the pressure in the cylinder and the valve itself or the spring that the piston reaches just before the bottom dead center during the explosion stroke, or by the balance of the spring. Or an electronically controlled auxiliary exhaust valve, which opens the exhaust port only during the explosion stroke and closes the piston just before the lower dead center during inhalation. I have. In addition, the piston is closed during the process in which the suction ends and the piston moves from the lower dead center to the compression stroke. On the other hand, it is open immediately after the explosion stroke and after the exhaust stroke.

The opening and closing timing of the auxiliary exhaust valve described above is determined by the balance between the pressure in the cylinder and the elastic force of the auxiliary exhaust valve itself or a spring, or mechanically using a cam, a rotary valve, a slide valve or the like. It can be executed by any means or electronic control. Since the auxiliary exhaust valve is required to have heat resistance of several hundred degrees, it is desirable to use metal from the viewpoint of durability. For example, the auxiliary exhaust valve is made of the same material as the intake and exhaust valves currently used. It can also be made of carbon or ceramic.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIGS. First, in FIG. 1, 1 is a 4-cycle engine,
2 is a cylinder, 3 is a piston, 4 is a piston arm,
5 is a crankshaft, 6 is an intake port, 7 is an intake valve, 8
Is an exhaust port, 9 is an exhaust valve, 10 is a camshaft, 10a
Is a cam.

Reference numeral 11 denotes a cylinder 2 and a piston 3
Is an auxiliary exhaust port which opens just before reaching the bottom dead center. This auxiliary exhaust port 11 opens in a slit shape in the cylinder wall 2a, and an auxiliary exhaust valve 12
Is attached. Reference numeral 13 denotes an auxiliary exhaust pipe, and the exhaust from the auxiliary exhaust port 11 is exhausted via the auxiliary exhaust pipe 13.

Next, the operation of the engine having the above configuration will be described. 1. Suction stroke (FIGS. 2, 3) The suction valve 7 opens, the piston 3 descends (FIG. 2), and the air-fuel mixture is sucked into the cylinder 2. When the piston 3 reaches the lower dead center, the piston 3 is located below the auxiliary exhaust port 11, the auxiliary exhaust port 11 is open, but the auxiliary exhaust valve 12 is closed, and the airtightness in the cylinder 2 is maintained. (Figure 3).

2. Compression stroke (FIG. 4) The intake valve 7 and the exhaust valve 9 close, and the piston 3 rises to compress the air-fuel mixture. At this time, the auxiliary exhaust port 1
1 is closed by a piston 3. At the same time, the auxiliary exhaust valve 12 is also closed.

3. Explosion stroke (FIG. 5) The ignition is performed by the spark plug and the piston 3 descends. At this time, the piston 3 is engaged with the exhaust auxiliary port 11 and is closed. At this time, in the conventional engine, since the exhaust valve 9 opens before the piston 3 comes to this position, energy is lost, but in this engine,
Even when the piston 3 is at this position, the combustion gas pressure is converted into motive power and there is no loss.

4. Exhaust stroke (FIGS. 6, 7, 8) (1) The piston 3 is located below the auxiliary exhaust port 11 at the lower dead center, and the auxiliary exhaust port 11 is open. When the pressure of the exhaust gas passes through the auxiliary exhaust port 11 and impinges on the auxiliary exhaust valve 12, the auxiliary exhaust valve 12
Are deformed, and the exhaust gas passes through the auxiliary exhaust pipe 13 to the outside from the gap (FIG. 6).

(2) The exhaust valve 9 of the cylinder head is opened from near the bottom dead center of the piston 3, and a normal exhaust stroke is performed. Auxiliary exhaust port 1 as piston 3 rises
1 is closed and the auxiliary exhaust valve 12 is also closed (FIG. 7). Since a large amount of exhaust gas has already been exhausted from the auxiliary exhaust port 11, the remaining amount of exhaust gas is small, and it is sufficient to open the exhaust valve 9 at a later timing than a normal engine. For this reason, the exhaust valve 9 can be made smaller than an ordinary engine. On the other hand, the suction valve 7 can be made large.

(3) Although both the intake valve 7 and the exhaust valve 9 are open, since the exhaust gas is efficiently exhausted, the pressure in the cylinder 2 is low, the intake efficiency is good, and the intake valve 7 can be enlarged. Therefore, the intake efficiency is further improved (FIG. 8).

FIG. 9 shows the auxiliary exhaust valve 12 with the spring 1
In this embodiment, the spring 14 is pressed by the combustion gas pressure and the auxiliary exhaust valve 12 is opened. During the suction stroke, the auxiliary exhaust valve 12 remains closed. In addition,
When the piston 3 falls below the auxiliary exhaust port 11 in the suction stroke of FIG. 3, the pressure in the cylinder 2 becomes a slight positive pressure or a slight negative pressure. The auxiliary exhaust valve 12 is closed by elasticity or, in the case of negative pressure, by atmospheric pressure. In any case, the elasticity of the auxiliary exhaust valve 12 and the valve spring 14 are set so that the auxiliary exhaust valve 12 is not opened at such a pressure.
In the suction stroke, the cylinder 2
The inside is kept airtight.

If the height of the port is made low and the width is made wide, it is effective even if the auxiliary exhaust valve 12 is not provided outside. Outflow when the intake air at the time of intake is positive pressure and loss of the intake effect when the intake pressure is negative pressure can be solved by devising the shape of the auxiliary exhaust pipe 13 connected to the exhaust port 8.

[0026]

As described above, the present invention has the following effects by providing the auxiliary exhaust port immediately before the bottom dead center of the piston. 1. By providing an auxiliary exhaust port in the cylinder and providing an auxiliary exhaust valve outside the auxiliary exhaust port and using it in combination with a conventional exhaust valve, the exhaust capacity is greatly improved. Therefore, the timing for starting the exhaust can be greatly delayed from the timing for starting to open the conventional exhaust valve. In other words, the gas pressure during combustion pushes down the piston and the time for conversion to motive power can be prolonged, so that the power is increased and fuel consumption is improved.

2. Since the exhaust capacity is improved by adding the auxiliary exhaust port, the exhaust valve can be made smaller than before. Therefore, the intake valve side can be set large. Therefore, the suction efficiency is improved and the power can be increased. 3. Since the exhaust can be performed in a short time, the overlap time in which the intake and exhaust valves are simultaneously opened is reduced, the direct discharge of the intake is reduced, the fuel efficiency is improved, and the air pollution by the non-combustible gasoline is reduced. 4. Since the exhaust efficiency is improved, the pressure in the cylinder at the time of exhaust (when the piston is raised) is reduced, the efficiency of charging the air-fuel mixture is increased, and the power can be further increased.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a four-cycle engine embodying the present invention.

FIG. 2 is an explanatory diagram of a suction stroke.

FIG. 3 is an explanatory diagram of a suction stroke.

FIG. 4 is an explanatory diagram of a compression process.

FIG. 5 is an explanatory diagram of an explosion process.

FIG. 6 is an explanatory diagram of an exhaust stroke.

FIG. 7 is an explanatory diagram of an exhaust stroke.

FIG. 8 is an explanatory diagram of an exhaust stroke.

FIG. 9 is an explanatory view of an embodiment in which an auxiliary exhaust valve is operated by a spring.

[Explanation of symbols]

 Reference Signs List 1 4 cycle engine 2 cylinder 3 piston 4 piston arm 5 crankshaft 6 intake port 7 intake valve 8 exhaust port 9 exhaust valve 10 camshaft 10a cam 11 auxiliary exhaust port 12 auxiliary exhaust valve 13 auxiliary exhaust pipe 14 spring

Claims (7)

[Claims] 1. An intake, compression, explosion, and exhaust stroke.
In the cycle engine, an auxiliary exhaust port is provided in the cylinder wall that opens just before the piston reaches the bottom dead center, and the auxiliary exhaust port is opened just before the piston reaches the bottom dead center during the explosion stroke, and the auxiliary exhaust port is opened therefrom. A four-stroke engine with a power-up configuration in which the piston is closed immediately before reaching the bottom dead center during the intake stroke so that the intake air is not missed. 2. An auxiliary exhaust valve is attached to an auxiliary exhaust port, and a control means for controlling the auxiliary exhaust valve to be opened during an explosion stroke and closed during an intake stroke is provided. The four-stroke engine according to claim 1. 3. The four-stroke engine according to claim 2, wherein the auxiliary exhaust valve is opened and closed by a balance between an internal pressure in the cylinder and a spring. 4. The four-stroke engine according to claim 2, wherein the auxiliary exhaust valve opens and closes based on a balance between an internal pressure in the cylinder and an elastic force of the valve itself. 5. The four-stroke engine according to claim 2, wherein the opening and closing of the auxiliary exhaust valve is controlled by a cam. 6. The four-stroke engine according to claim 2, wherein the opening and closing of the auxiliary exhaust valve is controlled by a rotary valve. 7. The auxiliary exhaust valve according to claim 2, wherein opening and closing of the auxiliary exhaust valve is controlled by a slide valve.
Cycle engine.