JPH0477136B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine that utilizes intake inertia, exhaust inertia, or both.

[Prior Art] Various intake and exhaust inertia devices have been known that utilize the inertia of intake or exhaust to improve intake efficiency or exhaust efficiency.

This type of device has a configuration in which, for example, a resonance chamber communicating with the intake manifold is provided upstream of the intake manifold communicating with the intake port of the engine.

The action of this resonance chamber is that when the engine's intake air passes through this resonance chamber, it vibrates at a natural frequency determined by the shape of the resonance chamber and intake manifold.
The idea is to generate intake pressure pulsations within the resonance chamber and intake manifold.

As a result, when the intake stroke of the engine starts and the intake port is opened, when the pressure inside the intake manifold on the downstream side (intake port side) of the intake manifold increases due to the above pressure pulsation, a large amount of intake air is It is pumped into the intake port, improving the engine's intake efficiency.

On the other hand, the engine speed increases or decreases depending on the engine load, and the opening/closing timing of the engine intake port changes accordingly. When the opening/closing timing of the intake port changes, the frequency of the pressure pulsation in the resonance chamber remains unchanged at a constant natural frequency, so the opening/closing timing of the intake port and the timing of the pressure pulsation become different, resulting in a decrease in intake efficiency. It may decrease. This will be explained with reference to FIG.

Figure 10 shows the opening/closing timing of the intake port IN, exhaust port EX, and scavenging port S, and the inside of the resonance chamber of the intake system when the resonance chambers are provided in both the intake system and the exhaust system of a two-stroke gasoline engine. It shows the relationship between a pressure wave P1 representing the state of the pressure pulsation of the generated intake air and a pressure wave P2 representing the state of the pressure pulsation of the exhaust gas generated in the resonance chamber of the exhaust system.

This figure shows an engine having a resonance chamber set to improve intake efficiency at high speed rotation (8000 rpm) when it rotates at medium speed (6000 rpm).

At the time point I _O when the intake port IN is opened by the piston, an intake pressure wave P1 is generated and starts to vibrate at a constant natural frequency. This pressure wave P1 is
The positive pressure portion after the negative pressure region 710 at time _IO (upper portion in the figure) exerts the effect of forcing the intake air from the intake port to the crank chamber of the engine. By the way, in the above-mentioned negative pressure region 710, since the piston is in the ascending process, the pressure in the crank chamber is in the descending process, so there is no backflow of intake air, but when the piston exceeds the top dead center TDC,
While the pressure in the crank chamber begins to rise,
The pressure wave P1 begins to fall. In the region where the pressure inside the crank chamber overcomes the pressure wave P1, that is, between the top dead center TDC and the closing point I _C1 of the intake port IN, for example, in the intake backflow region 71 shown with diagonal lines, the intake air flows from the crank chamber. The air flows back into the intake port IN, reducing intake efficiency.

On the other hand, at the time E _O when the exhaust port EX is opened by the piston, an exhaust pressure wave P2 is generated.
This pressure wave P2 exhibits the effect of suctioning exhaust gas from the exhaust port due to its negative pressure portion (lower portion in the figure). However, the piston is at bottom dead center.
When the pressure inside the combustion chamber exceeds BDC, the pressure inside the combustion chamber starts to rise, so when the negative pressure region 72 shown by diagonal lines is located between the closing time S _C of the scavenging port S and the closing time E _C1 of the exhaust port EX, the negative pressure As a result, the fresh air that has already been filled into the combustion chamber is discharged to the outside from the open exhaust port EX, resulting in a decrease in charging efficiency and a decrease in output and thermal efficiency.

When the engine is rotating at high speed, the closing points of the intake port IN and the exhaust port EX shift to I _C2 and E _C2 , respectively, indicated by broken lines, so the above problem does not occur.

Note that a four-cycle gasoline engine does not have a scavenging port, so fresh air is not sucked in, and the problem with the exhaust system described above does not occur, but the problem with the intake system similar to that described above occurs.

In this way, the above device vibrates the intake and exhaust air at a certain natural frequency in engines such as vehicles where the engine speed increases and decreases significantly, so the intake and exhaust efficiency improves depending on the engine speed. It may not.

In view of this problem, a device is known in which a vibrator that vibrates the intake air in the resonance chamber of the intake system at a desired frequency is attached to the side wall of the resonance chamber (for example, Utility Model Application No. 58-14425 (see official bulletin). This device changes the engine speed by appropriately changing the frequency of the intake pressure pulsations generated in the resonance chamber in accordance with the opening timing of the engine intake port, which changes depending on the engine speed. The aim is to prevent the reduction in intake efficiency associated with this.

That is, to explain this using FIG. 11, the intake air is excited at a frequency lower than the natural frequency, and a pressure wave Px that is longer than the wavelength of the pressure wave P1 of the natural frequency is generated.
This is intended to eliminate the negative pressure region 71.

[Problem to be solved by the invention]

However, due to the nature of the above pressure wave Px,
Because it does not match the pressure wave P1 of natural frequency,
Since the pressure difference is small and only weak pulsations occur, intake efficiency does not improve.

This problem similarly occurs when the exhaust system is provided with a resonance chamber having a vibrator similar to that described above.

This invention was made in view of the above-mentioned conventional problems, and it vibrates the intake and exhaust air at a certain natural frequency to generate strong pressure pulsations, thereby suppressing the pressure pulsations that occur as the engine speed increases and decreases. The aim is to eliminate unnecessary parts and improve intake and exhaust efficiency regardless of engine speed.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a timing valve in at least one of the intake passage and the exhaust passage constituting the gas passage, and the opening time of the gas passage is independent of changes in engine speed. A valve control device controls the opening and closing timing of the timing valve so that the timing corresponds to the natural frequency of pressure pulsation in the gas passage. Further, a vibrator is provided in the gas passage provided with the timing valve, and this exciter is driven by a driving device to generate a vibration at a frequency that matches the above-mentioned natural frequency of the gas passage and to open the gas passage. The gas is excited according to the timing.

[Operation] According to the present invention, since the gas passage is opened for a certain period of time corresponding to the natural frequency of the pressure pulsation, this certain period of time can be set to, for example, one period or one and a half periods of the natural frequency. According to the 10th
It is possible to prevent the backflow of intake air and new wasteful outflow as explained in the figure. In addition, since the exciter generates an excitation pulse in the gas passage that matches the natural frequency, strong pressure waves can be obtained even in the low rotation range, preventing the above-mentioned backflow of intake air and outflow of fresh air. Can be effectively prevented.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a first embodiment, in which:
11 is a two-stroke gasoline engine, and the intake port IN and exhaust port EX of cylinder 12 are
is opened and closed by a piston 13 that moves up and down.

The gas passage includes an intake passage 17, an exhaust passage 18, and a scavenging passage (not shown), and a first timing valve 21 is provided in the intake passage 17.
A second timing valve 22 is provided in each exhaust passage 18, and each timing valve 21, 22
When viewed from above, first and second exciters 2 each consisting of a voice motor are located on the opposite side of each port IN, EX.
3 and 24 are arranged. These exciters 23,
Reference numeral 24 has a structure similar to that of a speaker of an audio device, and when the coil 25 is energized, a vibrating body 26 vibrates and generates an excitation pulse, which causes passages 17 and 18 to vibrate.
Excite the gas inside.

The vibrators 23 and 24 are driven by a vibrating device 27. This drive device 27 receives a detection signal from a well-known crank angle sensor 28 and supplies power to the coils 25 of the vibrators 23 and 24, and at the time when the intake port IN corresponding to a certain crank angle is opened,
The first exciter 23 generates an excitation pulse, and the second exciter 24 is controlled to generate an excitation pulse when the exhaust port EX is opened, which also corresponds to a certain crank angle.

As shown in FIG. 2, the first timing valve 21 has a rotating shaft 29 fixed thereto, which is connected to a bearing 3.
The second timing valve 22 is rotatably supported by an intake manifold 31 via a bearing 33, and a rotating shaft 32 fixed thereto is rotatably supported by an exhaust manifold 34 via a bearing 33.

Both timing valves 21 and 22 are opened and closed by a valve control device 35, and the opening times of the intake passage 17 and exhaust passage 18 correspond to the natural frequencies of these passages 17 and 18, regardless of changes in engine speed. It is controlled to be a certain period of time. The natural frequencies of the pressure pulsations in the intake passage 17 and the exhaust passage 18 are usually set to be the same, so that the inertia of the intake or exhaust air is effectively utilized in a certain high rotation range.

The valve control device 35 includes both the rotation shafts 2
9 and 32, respectively, and a phase adjustment device 38 attached to the crankshaft 20, a timing gear 39 fixed to the outer periphery of the phase adjustment device 38, and a timing gear 36 fixed to the timing gear 36, respectively. , 37, and a toothed belt 40 is stretched between them. Details of the phase adjustment device 38 are shown in FIG.

In FIG. 3, a support member 42 is fixed to the crankshaft 20, and a rotor 43 that rotates due to centrifugal force is attached to the support member 42.
It is rotatably supported around 4. On the other hand, the crankshaft 20 has a spline 4 along the axial direction.
5, a movable plate 46 is mounted so as to be movable in the axial direction, and a spring force is applied to the movable plate 46 in an axially outward direction 48 by a spring 47.

Further, a drum 51 having the timing gear 39 on its outer periphery is fitted into the crankshaft 20 so as to be rotatable with respect to the crankshaft 20, and the drum 51 and the movable plate 46 are connected in the axial direction. They are connected via a diagonal spline 52 that extends diagonally to the other side. Further, a coupling member 53 fixed to the movable plate 46 is engaged with the tip of the rotator 43, and the rotator 43 is moved to the arrow 5 by centrifugal force.
When rotated in four directions, the movable plate 46 moves axially inward 55 via the engagement member 53, and this movement causes the drum 51 to rotate slightly relative to the crankshaft 20 via the spline 52. However, the phase relative to the crank angle changes.

Therefore, the drum 5 via the toothed belt 40
The phases of the timing gears 36 and 37 interlocked with the timing gear 39 of FIG.
The phase of the opening/closing timing of the timing valve 21 and the second timing valve 22 changes as the rotational speed increases so as to proceed toward the larger crank angle.

In the above configuration, the intake passage 17 and the exhaust passage 18 shown in FIG. Ru. On the other hand, the vibrator 23, 24
Accordingly, an excitation pulse is sent into the intake passage 17 and the exhaust passage 18 in synchronization with the opening timing of the intake passage 17 and the exhaust passage 18. These timings are shown in FIG.

In Figure 4 A, the engine rotation speed is 2000 rpm (low rotation)
The case is shown below. First timing valve 2
1 is opened and closed before the intake port IN. The opening time T1 of the intake passage 17 is the time during which both the first timing valve 21 and the intake port IN are in an open state. On the other hand, the vibration pulse Pu1 of the frequency shown in FIG. 4A, which matches the natural frequency of the pressure pulsation in the intake passage 17, is generated by the vibrator 23 (FIG. 1) at the time when the intake port IN is opened.
One wave (for one cycle) is generated at I _O , that is, at the opening timing of the intake passage 17, and as a result, a strong pressure wave P10 having the above-mentioned natural frequency is generated, and its positive pressure portion (upper side) causes intake port
It can be pushed into the crank chamber 61 (Fig. 1) from the IN.

Here, the opening time T1 is 1 of the pressure wave P10.
It matches the period, and the pressure wave P10 after the first period
is cut off by the closed first timing valve 21. Therefore, there is no risk that the negative pressure part after the first cycle will reach the intake port IN at the point when it exceeds top dead center TDC and cause backflow of intake air, unlike in the conventional case, and the filling rate, that is, the intake efficiency, improves. do. In addition, in Fig. 1, point X1 is
Indicates each pressure measurement point of Pu1, P1, P10,
2 indicates the pressure measurement points of Pu2, P2, and P20.

Here, even if the excitation pulse Pu1 in Fig. 4A is not generated, the pressure wave P1 is naturally generated due to the opening of the intake port IN, but in such a low rotation range, the naturally generated pressure wave P1 is weak, that is. Since the amplitude is small, the positive pressure portion cannot be expected to have much of an effect in pushing intake air. In contrast, in the present invention, as described above, the strong pressure wave P10 is obtained by the vibrator 23, so that a large pushing effect can be obtained by the strong positive pressure portion.

Next, the second timing valve 22 of the exhaust passage 18 is opened and closed before the exhaust port EX. Opening time T2 of exhaust passage 18
is the second timing valve 22 and exhaust port
This is the time when both EX are in the open state.
On the other hand, the exhaust passage 1 is
The excitation pulse Pu2 of the frequency shown in FIG. 4A, which matches the natural frequency of the pressure pulsation (same as the natural frequency of the intake passage 17) of No. 8, occurs when the exhaust port EX is opened.
One wave (for one cycle) is generated at E _O , that is, at the opening timing of the exhaust passage 18, and as a result, a pressure wave P20 with a strong natural frequency is generated, and its negative pressure part (lower side) causes To smoothly suck out exhaust gas into an exhaust passage 18. The amplitude of the pressure wave P20 gradually decreases under the influence of the combustion chamber pressure that decreases from the time point E _O when the exhaust port EX is opened.

Here, the opening time T2 is 1 of the pressure wave P20.
It corresponds to a period and a half, and the pressure wave P after one and a half periods
20 is cut by the second timing valve 22. Therefore, the negative pressure part after one and a half cycles is generated between the closing point S _C of the scavenging port S and the closing point E _C of the exhaust port EX, as in the conventional case.
Since the fresh air does not reach EX, wasteful flow of fresh air from the combustion chamber 62 into the exhaust passage 18 in FIG. 1 is prevented.

Note that on this exhaust side, like the above-mentioned intake side, even if the excitation pulse Pu2 shown in Fig. 4A is not generated, the pressure wave P2 is naturally generated due to the opening of the exhaust port EX. Since the naturally occurring pressure wave P2 is weak in this area, the effect of sucking out the exhaust gas into the exhaust passage 18 by the negative pressure portion cannot be expected to be very effective. On the other hand, in the present invention, as described above, the strong pressure wave P20 is obtained by the vibrator 24, so that a large suction effect can be obtained due to the strong negative pressure portion.

Next, in Figure 4 B, the engine speed is 6000 rpm.
(medium rotation), and the relationship between the pressure waves and the opening/closing timing of each port is almost the same as in the conventional FIG. 10. This rotation speed is for each port IN,
The opening times of EX and S are one-third of those shown in FIG. 4A, but of course they are the same in terms of crank angle.

In FIG. 4B, the opening/closing points 21 _O and 21 _C of the first timing valve 21 are delayed in terms of the phase of the crank angle by the phase adjustment device 38 in FIG. 4 compared to the case in FIG. 4A. In other words, the opening time T1 of _the intake _passage 17 is the same as in the case of FIG. 4A. is kept at a constant value. As a result, the intake passage 1 in FIG.
In the pressure wave P10 of No. 7, the negative pressure portion 71 indicated by diagonal lines after one cycle is cut off by the closed first timing valve 21, so that the negative pressure portion 71 exceeds the top dead center TDC. Intake port IN
does not reach. Therefore, there is no risk of backflow of intake air.

Furthermore, the opening/closing points 22 _O and 22 _C of the second timing valve 22 also change to be delayed in terms of the phase of the crank angle compared to the case shown in FIG. The time T2 is kept at the same constant value as in FIG. 4A. As a result, after one and a half cycles of the pressure wave P20 in the exhaust passage 18, a negative pressure portion 72 indicated by diagonal lines is cut off by the closed second timing valve 22, so that the negative pressure portion 72 is connected to the scavenging port. Closing point of S
Between S _C and the closing point E _C of exhaust port EX, it will no longer reach exhaust port EX. Therefore, wasteful outflow of fresh air is prevented.

In Figure 4 C, the engine speed is 8000 rpm (high rotation)
The case is shown below. At this speed, each port
The opening time of IN, EX, and S is further shortened, and the first
Opening/closing time of timing valve 21 21 _O , 21
_C , and the opening/closing times _22O , _22C of the second timing valve 22 are both further delayed in terms of crank angle. As a result, the intake port IN and the first timing valve 21 almost overlap, and the exhaust port EX and the second timing valve 22 completely overlap, so that, in effect, the first timing valve 21 and the second timing valve 22 is almost eliminated, the intake passage 17 is opened and closed almost only by the intake port IN, and the exhaust passage 18 is opened and closed only by the exhaust port EX.

Even at this rotational speed, as in the case of FIGS. 4A and 4B, backflow of intake air and wasteful outflow of fresh air are prevented. Note that in this high rotational speed region, the engine rotation and the natural frequencies of the intake passage 17 and the exhaust passage 18 match, which is a so-called matching state, and the first timing valve 21 and the second timing valve 22 are in a matching state. Even without it, backflow of intake air and outflow of fresh air are originally suppressed.

In the example shown in FIG. 4 above, the opening time T1 of the intake passage 17 is made to match one period of the natural frequency of the intake passage 17, and the opening time T2 of the exhaust passage 18 is made to match one cycle of the natural frequency of the intake passage 17.
Although the invention is not limited to this, the number of cycles to be matched depends on the maximum value of the engine rotation speed and the natural frequency of the passage. Determined by relationship.

For example, set the maximum engine speed to 5000rpm.
If the natural frequencies of the intake passage 17 and the exhaust passage 18 are set to a relatively low value and the natural frequencies of the intake passage 17 and the exhaust passage 18 are set high, the excitation pulses Pu1 and Pu2 need to match the natural frequency of the pressure pulsation of the intake passage 17 and the exhaust passage 18. Therefore, the pressure wave P1 on the intake side and exhaust side
0, P20 pulsation period is the above-mentioned each passage 17, 18
It matches the natural frequency of pressure pulsation.

On the other hand, the maximum value of the engine speed is set separately from the natural frequency of pressure pulsation in each of the passages 17 and 18.
As shown in FIG. 5, the opening times T1 and T2 of
It may match a period and two and a half periods, respectively.

Even in that case, as long as the negative pressure portion 71 of the first and a half period of the pressure wave P10 on the intake side does not greatly exceed the top dead center TDC, the backflow of intake air can be suppressed as much as possible.
The opening time T1 of the intake passage 17 may be made to match one and a half cycles of the pressure wave P10, or two cycles as shown in the figure. Similarly, in the pressure wave P20 on the exhaust side, there is no risk that the negative pressure portion 72 of the second cycle will enter between the closing time S _C of the scavenging port S and the closing time E _C of the exhaust port EX, so the exhaust The opening time T2 of the passage 18 may correspond to two periods of the pressure wave P20, or two and a half periods as shown.

By the way, in the above embodiment, the timing valves 21 and 22 and the vibrators 23 and 24 were provided in both the intake passage 17 and the exhaust passage 18 in FIG.
It goes without saying that it may be provided only in the intake passage 17 or the exhaust passage 18.

Furthermore, although voice motors were used as the vibrators 23 and 24 in FIG. Provided at the bend of the intake passage 17,
Gas vibrations in the exhaust passage 18 may be guided to the vibrator 23 through the communication pipe 82 to vibrate the vibrating membrane 81, thereby exciting the gas in the intake passage 17. in this case,
The communication pipe 82 constitutes the drive device of the present invention.

The vibrating membrane 81 is provided with a corrugated portion 83 to facilitate vibration. Normally, the natural frequencies of the intake passage 17 and the exhaust passage 18 are set to be the same, so the gas in the intake passage 17 is effectively added to the natural frequency by the gas in the exhaust passage 18 that vibrates at the natural frequency. Shaken. At this time, by appropriately setting the length of the communication pipe 82, the phase of the natural vibration in the exhaust passage 18 can be matched to the phase of the natural vibration in the intake passage 17. The intake air can be excited to coincide with the timing when the valve is released.

Furthermore, as in the third embodiment shown in FIG.
1 and a coil spring 84 that elastically supports the vibrating membrane 81.

In the embodiments shown in FIGS. 6 and 7 above, if the position of the vibrator 23 and the shape of the intake passage 17 are appropriately set, the vibrator 23 exhibits an amplifying effect like a transistor in an electric circuit. It can be expected that the gas in the intake passage 17 will be strongly vibrated.

Next, FIG. 8 shows an example in which the present invention is applied to a four-stroke gasoline engine.

In Fig. 8, the intake port IN is the intake valve 91.
The exhaust port EX is opened and closed by the exhaust valve 92. The intake passage 17 is provided with a timing valve 21 of the present invention and a vibrator 23 consisting of a voice motor. The sensor 93 detects the rotation angle of the rotation shaft 29 of the timing valve 21, and upon receiving the detection signal, the drive device 27 operates to determine the timing of excitation of the vibrator 23.

On the other hand, the opening/closing timing of the timing valve 21 is controlled by a valve control device 35 similar to that shown in FIG. 2, and the opening time T1 of the intake passage 17, which will be described later, is kept constant. The opening/closing timing of the timing valve 21 and the operation timing of the vibrator 23 are shown in FIG.

FIG. 9 shows the case of 6000 rpm, which is a high rotation speed for a four-cycle gasoline engine, and the effects described below are the same even in a lower rotation range. As is clear from FIG. 9, the timing valve 21 opens and closes later than the intake port IN. Therefore, the opening time T1 of the intake passage 17 is the time from the time point 21 _O when the timing valve 21 is opened to the time point I _C when the intake port IN is closed.

On the other hand, the vibrator 23 (FIG. 8) generates an excitation pulse Pu1 having a frequency that matches the natural frequency of the pressure pulsation in the intake passage 17 at the time point 21 _O when the timing valve 21 is opened, that is, when the intake passage 17 One signal (for one cycle) occurs at the opening timing of . Since the opening point 21 _O of the timing valve 21 is always constant when viewed from the rotation angle of the rotation shaft 29 of the timing valve 21 in FIG. ,
The vibration exciter 23 is driven by the drive device 27, and the vibration pulse Pu1 can always be generated at the opening point _21O of the timing valve 21. This excitation pulse Pu1 amplifies the pressure wave P1 of the natural frequency that is about to occur naturally at the opening point _IO of the intake port IN, generates a strong pressure wave P10, and a strong positive pressure portion of this pressure wave P10. (upper side) allows intake air to be forced into the combustion chamber 62 from the intake port IN in FIG. Therefore, the filling rate is improved.

Here, the opening time T1 is the pressure wave P1.
It is set to a constant time corresponding to one period of 0. Therefore, since the negative pressure portion 71 shown by diagonal lines at the first and a half period of the pressure wave P10 is cut off, there is no possibility of backflow of intake air due to this negative pressure portion 71, and the filling rate is further improved.

Also, connect the timing valve 21 to the intake port IN.
Since the opening is delayed, the following effect is obtained. That is, with the beginning of the inhalation stroke, the eighth
The suction negative pressure generated by the downward movement of the piston 13 shown in the figure gradually increases, but in the middle of the suction stroke when this suction negative pressure becomes sufficiently large, the intake passage 17 is opened by the timing valve 21. Since the intake air enters the combustion chamber 62 with force, the above-mentioned cutting of the excess portion of the pressure wave P10 by the timing valve 21 and the addition of force by the vibrator 23 significantly improve the filling rate of the intake air.

In addition, in the case of the embodiment shown in FIGS. 8 and 9, the opening time T1 of the intake passage 17 is set from one cycle of the pressure wave P10, as in the case of the two cycles shown in FIG. It is also possible to set it to a longer time.

[Effects of the Invention] As explained above, according to the present invention, regardless of changes in engine speed, the gas passage is opened only for a certain period of time corresponding to the natural frequency of its pressure oscillations. Since it is possible to prevent the backflow of intake air, wasteful outflow of fresh air, retention of exhaust gas, etc. in this area, intake efficiency or exhaust efficiency can be improved, and the output and thermal efficiency of the engine can be improved.

In addition, since the vibration exciter generates an excitation pulse in the gas passage that matches the above-mentioned natural frequency, strong pressure waves can be obtained even in the low rotation range, and the above-mentioned intake efficiency and exhaust efficiency are greatly improved. improves.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention, FIG. 2 is a plan sectional view showing the same embodiment, FIG. 3 is a longitudinal sectional view showing a phase adjustment device of the same embodiment, and FIG.
The figure is a characteristic diagram showing the operation of the same embodiment, FIG. 5 is a characteristic diagram showing the operation when the opening time of the intake passage and the exhaust passage are different in the same embodiment, and FIG.
FIG. 7 is a longitudinal sectional view showing the main part of the third embodiment, FIG. 8 is a longitudinal sectional view showing the fourth embodiment, and FIG. 9 is a longitudinal sectional view showing the fourth embodiment. FIG. 10 is a characteristic diagram showing the operation of a conventional example, and FIG. 11 is a characteristic diagram showing the operation of another conventional example. 17...Intake passage, 18...Exhaust passage, 21,
22... Timing valve, 23, 24... Vibrator, 27, 82... Drive device, 35... Valve control device, T1... Intake passage opening time, T2...
Exhaust passage opening time.

Claims (1)

[Scope of Claims] 1. An intake passage and an exhaust passage constituting a gas passage; a timing valve provided in at least one of the intake passage and the exhaust passage; a valve control device that controls the opening/closing timing of the timing valve so as to open only for a certain period of time corresponding to the natural frequency of the pressure pulsation; An engine that utilizes the inertia of gas and is equipped with a vibrator that vibrates gas at a frequency that matches the vibration frequency, and a drive device that drives the vibrator in accordance with the timing when the gas passage is opened. 2. The timing valve on the intake side is opened and closed such that the fixed opening time for opening the intake passage coincides with one period of the natural frequency of the pressure pulsation of the intake passage. engine using. 3. The timing valve on the exhaust side in a two-stroke engine is opened and closed such that a certain opening time for opening the exhaust passage coincides with one and a half periods of the natural frequency of pressure pulsation in the exhaust passage.
An engine that utilizes the inertia of a gas according to item 1 or 2.