JPH01219314A - Rotary pipe valve structure of two-stroke gasoline engine - Google Patents

Abstract

PURPOSE: To prevent new gas from leaking out by providing a rotary pipe valve in the vicinity of an exhaust port of a cylinder body and injecting compressed air at the end of the exhaust stroke. CONSTITUTION: A rotary pipe valve 2 is arranged near an exhaust port 181 of a cylinder body 12. The interior of a circular pipe 21 of the valve 2 is connected to a compressed air source. A longitudinal opening 211 is formed in the circular pipe 21. Compressed air is injected from the opening 211 to the vicinity of the exhaust port 181 at the end of the exhaust stroke. In this way, new gas is prevented from escaping from the exhaust port. Leakage of new gas is prevented.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a kind of rotating pipe pulp structure of a two-stroke gasoline engine, especially a kind of rotary rotary that rotates synchronously with the crankshaft (same direction or opposite direction). A rotary valve device is used to compress the compressed pulp filled into the rotary pulp using the fact that the opening on the rotary pulp sometimes matches the timing with the two passages above the pulp seat. The compressed air is injected into the exhaust port or crankshaft box through two passages above the valve seat, which prevents fresh air from leaking out and also increases the pressure of fresh air in the cylinder. Alternatively, it can be used to increase the pressure of the scavenging air flow; this increases the efficiency of the two-stroke gasoline engine.

(Prior art) A two-stroke gasoline engine has advantages such as simple structure, low production cost, easy maintenance, and stable output, but at the same time has disadvantages such as high oil consumption and high exhaust pollution.
Today, when pressure for energy conservation and environmental protection increases, the problem must be solved.

The main causes of the disadvantages such as the high oil consumption rate and high exhaust pollution mentioned above are:
When the engine is in the exhaust process, part of the air-fuel mixture that enters the new cylinder is directly discharged from the exhaust port together with the exhaust gas, which normally increases the exhaust rate by 25 to 40%.

Normally, the engine is designed with appropriate dimensions such as the length of the exhaust pipe and the expansion pipe and tapered pipe inside the exhaust pipe, so that the exhaust gas is returned to the exhaust port through the expansion pipe and tapered pipe, and the pressure wave is used to apply an appropriate pressure to the cylinder. It provides pressure and counter pressure, promotes the removal of exhaust gas, and prevents fresh air from being discharged from the exhaust pipe. Combining these positive pressure and counter pressure waves with engine progress and exhaust timing is called exhaust timing alignment. , the ideal relationship is that when the piston is at the lower dead point, the inlet is open and the outlet is under reverse pressure, and conversely, from the time the inlet is idle until the outlet is closed. In this case, the exhaust port is under positive pressure. However, since the pressure wave transfer speed (sound speed) is unrelated to the engine rotational speed, once the exhaust pipe dimensions are designed and fixed, the exhaust pressure wave has a timing adjustment effect only within a certain engine rotational speed range. However, outside the rotational speed range, the timing effect cannot be achieved, and on the contrary, it has a bad effect, for example, if the pressure wave is too early, it will interfere with the back pressure of the exhaust gas, and the gas exchange rate will be low. If it is too late, fresh air will leak out and the volumetric effect will be reduced.

(Problems solved by the invention) The purpose of the present invention is to provide a device that prevents fresh air from leaking out from outside the exhaust port using jet airflow, and the jet timing is synchronized with the rotation of the engine, so it can be adjusted to any rotational speed. Timing alignment can be achieved, and it is no longer limited by exhaust pressure waves.

Another object of the present invention is to increase the pressure of the engine's advance air with the above-mentioned injection airflow, that is, increase the appropriate amount of air, promote combustion, and reduce the output height and exhaust pollution. be.

Another object of the present invention is to provide a simple pulp structure that is blended synchronously with the engine rotation to achieve the functions of increasing the pressure of the engine air with the above-mentioned injection air flow and preventing fresh air from leaking out.

In order to achieve the above-mentioned object, the present invention comprises a circular pipe, which is composed of a circular pipe and a large dust, which installs a rotary valve at a suitable position on the cylinder surface outside the engine exhaust port. There is one opening on the circumference, and it is paired with two passages that collect large amounts of dust as the pipe rotates.The two passages are led separately to the exhaust port and crankshaft box, and the inside of the pipe is The introduced compressed air is ejected through these two passages to the exhaust port to prevent fresh air from leaking out, or to the crankshaft box to increase the pressure of engine return air. Since the rotation of the pipe is mechanically coupled with the rotation of the engine crankshaft, it is possible to synchronize the jet air with the rotation of the engine.

After the ignition of the two-stroke engine explodes, the piston is pressed down, and then the exhaust port is opened, and the high-pressure waste air in the cylinder is naturally discharged from the cylinder, and then the inlet is opened to the oven. The compressed fresh air that fills the crankshaft box enters the cylinder through the inlet and scavenges it, while also pushing the low-pressure waste air to the exhaust. When the piston passes through the lower dead point and rises to enter the inlet, the exhaust port is still open, and at this time the opening of the rotating pipe aligns with one of the passages (that passage (exhaust flow lead), the high-speed airflow may be ejected, and these high-speed airflows will form an air curtain near the exhaust port to prevent fresh air from leaking out. Subsequently, the piston is continuously pressed upward (the rotating pipe also rotates in synchronization), the exhaust port is opened, and the high-speed air jetting operation of the rotating pipe is also stopped.

As the piston continues to rise and is just short of the upper dead point, the opening in the rotary pipe valve mates with another passage opening (which leads to the crankshaft box) and the compression Spraying airflow into the crankshaft box: When the piston passes the upper dead point, the rotary pipe valve's compressed airflow jetting action also stops. Subsequently, the piston moves downward under the action of the two-stroke engine power stroke, and this movement recompresses the compressed air filling the crankshaft box, thus increasing the advance and exhaust efficiency of the two-stroke engine.

(Embodiment) Referring to FIG. 1, FIG. 1 is a cross-sectional view of the present invention installed in a two-stroke engine that supplies air-fuel mixture with an ordinary carburetor. Cap ll, cylinder body 12 and crankshaft box 1
3, in which the piston 14, rack 15 and crankshaft 16 move. The crankshaft box 13 has a one-side closed air inlet consisting of a spring valve 171, and a double airway 191,1 opened symmetrically to the exhaust port 181 leading to the cylinder 18.
92 (Fig. 2A) and the third arch airway 1 opposite the exhaust port.
Includes 93.

As is well known, during the upward movement of the piston 14, the air-fuel mixture supplied by the carburetor (not shown) is released from the return air port 17 by the action of a pressure difference, and the spring valve 171 is injected into the crankshaft. Enter the shaft box 13. At the same time, the cylinder 18 above the piston 14
When the air-fuel mixture inside is compressed and the piston approaches the upper point, it is ignited to generate power and press the piston downward. The air-fuel mixture in the cylinder 18 is compressed in advance by the downward movement of the piston 14, and the high-pressure waste air in the cylinder 18 is discharged as soon as the exhaust port 181 is exposed, and then the airways 191, 192, 19 are discharged.
3 are exposed one after another, the pre-pressurized air-fuel mixture in the crankshaft box 183 enters the cylinder 18, and the low-pressure exhaust gas is pushed out to the exhaust port 181. After the piston 14 has passed the lower dead point, it is moved upward again. When the airway 191, 192, and 193 are to be accessed one after another, the exhaust port 181 is also in a closed state, and at this time,
Because the space inside the cylinder 18 is reduced due to the flow inertia of the advancing and exhaust gases and the rise of the piston 14, fresh air is easily followed by beriberi and leaks from the exhaust port 181, increasing wasteful gasoline consumption and pollution. do.

Therefore, the present invention provides a compressed air injection device,
At the end of the exhaust timing, a powerful air stream is injected into the 18L part of the exhaust port to form an air curtain and stop the leakage of fresh air; The return air is blown into the cylinder 18 and crankshaft box 13 to increase the pressure. The best embodiment of this is to install one rotary pipe pulp 2 in the cylinder body 12 at an appropriate position near the exhaust port 181, and install one circular pipe 21 in the circular large dust 20 in the cylinder body 12. It is composed by The large dust 20 has a first passage 201 communicating with the exhaust port 181 and a second passage 202 communicating with the crankshaft box on its circumferential surface, and the inside of the pipe 21 is connected to compressed air R (not shown). Moreover, the elongated opening 211, which is closed on the circumferential surface of the pipe 21, is paired with the two passages 201 and 202, so that compressed air can come out only when blowing into the exhaust port 181 or the crankshaft box. , that is, when the compressed air is closed at other times, the pipe 2
The rotation of the pipe 21, which is inserted into the inside of the crankshaft 16, is synchronized with the rotation of the crankshaft 16, and the method for doing so is simply to connect the two with a well-known linked VJ device such as a gear, belt, or chain. This can be achieved, and with the design of a suitable relative position between the opening 211 and the passage 201, 202, the timing of the jet just coincides with the end of the exhaust of the cylinder 18 and the end of the return air of the crankshaft box 13.
Such formulations and effects will be explained again in the operating sequence shown in Figures 2A to 2D. In these figures, the pipe 21 is connected to the crankshaft 16 in a synchronous and reverse connection state.
In Figure A, the piston 14 is located at the lower dead point, and the exhaust port 181 and each of the air passages 191, 192, 19
3 are all in the open state, and most of the produced air in the cylinder 18 is exhausted from the exhaust port 181, before the pipe valve opening 211 reaches the position of the first passage 201.

Subsequently, when the piston 14 moves upward and the timing shown in FIG.
However, the exhaust port 181 is also not completely closed, and at this time, the pipe opening 211 is opposed to the first passage 201, and air is ejected into the exhaust port 181 in the direction indicated by the arrow.
It is possible to stop the fresh air leaking from the exhaust port 181, and also to blow the air back into the cylinder 18.
The air-fuel mixture pressure in the air-fuel mixture can be increased, thereby promoting complete combustion when the air-fuel mixture is combusted, thereby reducing the output machine height and exhaust pollution.

Of course, the blow strength is determined by the cross section of the opening 211 and the pressure of the compressed air source; this strength is determined by the pressure of the compressed air source.
The pressure of the air-fuel mixture coming out of the air-fuel mixture must be large; and the timing of the fume is determined by the opening 211 closing when it passes through the passage 201, and this timing should match the timing when the exhaust port 181 closes from the end of the expulsion. , these factors can be appropriately adjusted in the design to obtain the optimal effect.Generally speaking, the compressed air source can set a stable pressure, or it can be adjusted according to the engine rotation speed, for example at high rotation speeds. Since the supply of these air sources can be accomplished using common techniques, such as increasing the pressure when the rotational speed is high and reducing the pressure when the rotational speed is low, redundant explanation will be omitted here.

Regarding the airflow that is injected toward the exhaust port 181, the airflow that remains outside the exhaust port after the exhaust port is closed can also be used at the beginning of the exhaust of the next stroke of the engine, because it is used to remove the hot beriberi that the exhaust port blows out. Partially incompletely combusted air-fuel mixture inside
! It oxidizes to carbon dioxide and water vapor, thereby reducing serious air pollution.

FIG. 2C shows the situation after the exhaust port has emitted fumes. The pipe valve 2 has just rotated and opened, and the piston 14 has pierced the exhaust port 181 and ascended upward. Compress the mixture. At the same time, the crankshaft box 13 is about to introduce air through the air inlet 17 due to its increased volume.

By the time of FIG. 2D, the piston 14 has reached the upper dead point and is in the process of proceeding with a combustion explosion into the cylinder 18, and at this time the volume of the crankshaft box 13 has increased to its maximum and the piston 14 has reached its upper dead point. At the point where the suction action from the air outlet 7 stops, the pipe valve opening 211 just matches the second passage 202, and compressed air is injected into the crankshaft box 13 as shown by arrow d. The purpose is to raise the air-fuel mixture pressure in the crankshaft box 13, and then to increase the efficiency of air flow into the cylinder 18. Of course, the amount and timing of the jets may be adjusted during design depending on factors such as the cutting area of the closed opening 211, the pressure difference between the compressed air source and the crankshaft box 13, and the leap timing between the opening 211 and the passage 202. Can be mixed.

After the timing shown in FIG. 2D is over, the piston 14 is pushed downward by the power generated from the combustion explosion and moves.
As a result, the exhaust and intake processes proceed through the cycle, as shown in FIG. 2A.

Although the above operating conditions have been described with reference to a two-stroke engine that uses an air-fuel mixture mixed with gasoline before entering the crankshaft box, the present invention can actually be used in any type of two-stroke engine, such as a jet engine. This invention is particularly applicable to such a jet-type oil injection engine, which is a jet-type oil injection engine that supplies oil into the cylinder with a type oil injection device to inhale and drive fresh air into the crankshaft box. This is because these air-fuel mixture concentrations can be elastically controlled, and by adding the intake air pressure boosting effect of the present invention, the engine can achieve its maximum efficiency.

FIG. 3 is a sectional view of a two-stroke jet oil injection engine 5 in which the rotary pipe valve 2 of the present invention is installed in the cylinder. The engine 5 has roughly the same structure as the engine shown in FIG.
6, intake port 57, spring valve 571, cylinder 58, exhaust port 581. II airways 591,592 (not shown) and 593, etc. However, the fuel for the engine is one jet oil injector 6 and cylinder 58.
As shown in the figure, one of the most suitable systems is to have one vaporizing chamber 541 inside the piston 54, facing the third airway 593, and having a vaporizing chamber 541, as shown in the figure. The fuel is first injected into the vaporization chamber 541, which opens in the direction of 6.
The high heat on the piston is absorbed and vaporized, and after being vaporized, it is stored for a while in the third airway 593 and then re-entered into the cylinder, and the air introduced from the crankshaft box 53 or pre-pressurized is simply fresh air. It's air. This design can lower the temperature of the piston, making it possible to increase the combustion efficiency of the engine (as the combustion efficiency increases, the engine temperature increases, and in a normal engine, the number of pistons is often (If not, there is a risk of burning.) Therefore, using it together with the present invention has the effect of killing two birds with one stone. rotary pipe valve 2
Regarding the configuration of the large dust 20, passages 201, 202,
Pipe 21. The opening 211 and its motion coordination with the piston 54 are similar to those described in FIGS. 2A to 2D above.

In addition, although only a single engine is depicted in the above-mentioned rotation, in reality, the present invention can be applied to a multi-cylinder engine, and of course, the pipe 21 can be inserted through a large number of cylinders.
The above function can be achieved by installing multiple closures 211 thereon and attaching first and second passages 201 and 202 to each cylinder individually.

[Brief explanation of the drawing]

1st y! U is a structural sectional view of the present invention, which is installed in a two-stroke gasoline/air premix engine. 2A to 2D are functional explanatory diagrams of the present invention,
The present invention and its engine are in four different positions during continuous rotation, in which Figure 2A) Yo' piston is down-i! - is a figure located at the rad point; the second
Figure B continues from Figure 2A and is a diagram showing the situation in which the present invention is applied to the exhaust gas; Figure 2C continues from Figure 2B;
The situation in which the engine and the present invention continue to operate: Figure 2D is a situation diagram where the piston is located at the upper dead point and the present invention injects into the crankshaft box. FIG. 3 is a structural sectional view of the present invention installed in a two-stroke oil jet engine. Applicant Industrial Technology Research Institute FIG, 1 FIG, 2A FIG, 2B FIG, 2C FIG, 2D

Claims (1)

[Claims] 1. A type of air injection device used in a two-stroke engine, which provides an air curtain at the end of exhaust in the cylinder to prevent fresh air from escaping from the exhaust port. In this system, a crankshaft box is installed, in which a cylinder in which a reciprocating piston moves, has one exhaust port at an appropriate position on the cylinder surface and multiple exhaust hole passages that individually communicate with the crankshaft box located below the piston. Air enters from an inlet via two valves; the air injection device includes: a cylindrical hole formed on the cylinder surface adjacent to the exhaust port; a circular pipe, rotatable but with axial movement limited to the above-mentioned hole, with an opening in its circumferential surface; By rotating until
Combined with the first passage described above; the pipe has another inlet, and apart from the aforesaid openings and inlets the pipe is closed; a source of compressed air, providing compressed air at a suitable pressure; The opening is connected to the inlet of the pipe, and connected to the interlocking device, the crankshaft box, and the above-mentioned pipe to rotate synchronously, and the timing of the engagement of the above-mentioned opening and the first passage is just after the engine has finished exhausting the exhaust port. Match the closing timing. 2. As in the device mentioned in claim 1, the cylindrical hole therein further comprises a second passage communicating with the crankshaft box, when the pipe is rotated to another angle. , the opening on the upper side matches the second passage, and the timing of the meeting is just when the crankshaft box has finished inlet air from the inlet, thereby increasing the pressure on the intake air of the crankshaft box. Can be done.