JPS5970836A - Intake device of rotary piston engine - Google Patents

Abstract

PURPOSE:To improve the output of an engine from its medium speed range, by both obtaining a supercharge effect through the proper pulsation effect of intake in each cylinder itself and supplementing a decrease of the output in the bottom part of pulsation with an exhaust interference effect mutually between cylinders, when the two-cylinder engine of side intake port type is driven at a high speed. CONSTITUTION:When an engine is driven at a high speed, an expansion wave, generated in passages 16a, 16b by a start of intake of an intake port 3, is repeated with the inversion and reflection to a compression wave by the adequate length of a passage between each intake port 3 and an expansion chamber 21 and propagated to the intake port 3 immediately before full closing in each cylinder 1A, 1B, and an output is improved by its own supercharge effect of the wave. While a compression wave, generated in, for instance, the passage 16b at opening, is propagated to the intake port 3 immediately before full closing with a 180 deg. phase difference in the cylinder 1A by setting the length of a passage between the intake ports 3, 3 from the range of medium speed. In such way, an output at the medium speed being the bottom part between the secondary pulsation and the tertiary pulsation in an intake proper pulsation effect can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an intake system for a rotary piston engine, and more specifically, for a two-cylinder rotary piston engine with a night intake port type, the present invention relates to an intake system for a rotary piston engine. This invention relates to a device that obtains a supercharging effect from medium rotation to high rotation.

In general, a two-cylinder rotary piston engine with a lead-in intake bow type has a two-section trochoidal inner circumferential surface.
A substantially triangular rotor is supported by an eccentric shaft and performs planetary rotation within a casing formed by a 1-star housing and a side housing equipped with an intake port 1- located on both sides of the casing and having an intake passage. The rotor of each cylinder has a phase difference of 180° in the rotation angle of the eccentric shaft, and the rotor of each cylinder has a phase difference of 180° with respect to the rotation angle of the eccentric shaft.
As the C rotor rotates, intake, compression, explosion, expansion, and exhaust strokes are performed in sequence.

By the way, it is well known that conventionally, in such a rotary piston engine, a supercharger is provided in the intake passage to supercharge the intake air, thereby increasing the charging efficiency and increasing the output. The feeding equipment required a large-scale structure and increased costs.

Conventionally, as a technique for obtaining a supercharging effect using intake pressure waves, as disclosed in Japanese Utility Model Publication No. 45-'2321, in a single-cylinder rotary revitalization engine, the intake pipe was brushed. The engine is divided into two passages with different diameters, each with its own intake boat, and when the engine is running at high speeds, the two intake passages are used, and when the engine is running at low rotations, the intake passage that is in the later position is closed to speed up the intake. J: It is possible to prevent eye blockage by using the XJ method of the intake pipe and the supercharging effect caused by the blockage of the intake air at the maximum pressure of the intake air, which is a function of the engine speed.
'A system has been proposed in which the preferred charging efficiency is 1q over the engine rotation range. But this one is
For a single-cylinder rotary visminer engine, it is not clear how to utilize the intake pressure waves generated in the intake passage, and it is not immediately practical. there were. Moreover, since Periport h is used as the intake port, intake ports 1~ communicate with the exhaust working chamber before the intake working chamber closes, and a supercharging effect is obtained by blowing back exhaust gas from the exhaust working chamber. That was the first problem. In particular, in recent commercial vehicles, the engine exhaust pressure has increased to reduce noise and purify exhaust gas, and at high speeds and high loads, a normal engine has a pressure of 400 to 600
mm HIJ (gauge pressure)
In the engine, the amount is 1000 mml100 O or more, and no improvement in filling efficiency by the Veriport method can be expected.

Therefore, the present inventors studied the intake characteristics of the lead intake boat in a rotary piston engine and found that (+) When the intake port 1 is opened, the intake air is compressed by the pressure of the residual exhaust gas in the working chamber, and the air inside the intake passage is compressed. Compression waves are generated in the intake port portion (i) It has been found that expansion waves are generated in the intake passage when the intake port begins to intake air. From this, the above (+) in one cylinder
If the frontage compression wave is applied to the other cylinder, especially the intake boat just before full opening, where intake air blowback occurs, the supercharging effect will be increased by 1g (hereinafter referred to as exhaust interference effect). It has been discovered that a supercharging effect can be obtained by inverting the expansion wave (n) into a compression wave and applying it to the intake bow 1- of each cylinder just before full opening (hereinafter referred to as the intake individual pulsation effect). It is. The above exhaust interference effect is
In recent years, catalyst devices for purifying exhaust gas have been installed in engine exhaust systems, and the exhaust pressure has been set high, so this effect is significant.

That is, the present invention provides a side-intake boat-type two-cylinder rotary revitalization engine as described above, during which the intake port is opened, the expansion is performed to connect the intake passages of each cylinder and to reverse expansion waves into compression waves. By appropriately setting the position of the chamber, the passage length from the enlarged chamber to the intake boats of each cylinder, and the passage length between the intake boats of the inner cylinders,
At high engine speeds of 00 to 7,000 ppm, supercharging is performed due to the intake pulsation effect, while at engine rotations where the troughs of the intake pulsation occur, supercharging is performed using the exhaust interference effect to compensate for this. With a very simple configuration by making slight changes to the existing intake system without using a supercharger etc., the engine speed can be increased from medium to high speeds of 11.4
The purpose of this is to increase filling efficiency and improve output.

In order to achieve this object, the configuration of the present invention includes a rotor housing having a two-node I-lochoid inner circumferential surface, and an intake boat located on both sides of the rotor housing with an intake passage opening therein. Inside the formed casing, a substantially triangular shape is formed. In a two-cylinder rotary vis 1 engine which is supported by a shaft and has a planetary rotation movement, and each cylinder has a phase difference of 180° at the rotation angle of an eccentric cylinder 71, a. - Setting the frontage period θ to be in the range of 270 to 32 degrees at the rotation angle of the eccentric 1 to the lift shaft; b. Setting an enlarged chamber having a communication passage that communicates the intake passages of each cylinder downstream of the throttle I to the lever valve. C1 Under the condition that the length 91 of the intake passage from the enlarged chamber to the intake boat of each cylinder is set to 0.35 to 0.63 m, 5000 to 7000 r. When the engine rotates at a high speed of 500 pm, the expansion wave generated in the intake passage by the start of intake from the intake boat of each cylinder is reversed in the expansion chamber and the secondary pulsating wave of the compression wave reflected is generated immediately before the joint cylinder is fully opened. While supercharging is carried out by propagating to the intake boat, when the engine rotates when the trough between the secondary pulsating wave of the compression wave and its tertiary pulsating wave occurs, there is a supercharging inside the intake passage when the intake port of one cylinder is opened. The generated compression wave is propagated through the communication passage to the intake bow 1- of the other cylinder just before it is fully opened, thereby performing supercharging. The exhaust interference effect increases the charging efficiency from the mid- to high-speed range of the engine.

Here, the limitation of 5000 to 7000 ppm at high engine speed to eliminate the intake air pulsation effect is as follows:
Generally maximum output d3. 1 and the maximum speed are set within this range, which is a high load, high rotation operating range of the engine, which is an effective range for improving C1 charging efficiency and output.

In addition, the engine rotation range N2 to obtain the exhaust interference effect is 5000 to 70 to obtain the secondary pulsation in the intake right pulsation effect.
In order to compensate for the valley between the reference rotation speed N1, which is set within the range of 00 ppm, and the third pulsation (engine rotation N+/1.5),
/1.25), and the engine rotation range is set to the middle of the front and back.
±0.125) Howl.

In addition, regarding the setting of the intake boat opening period θ in setting item a above, the lower limit of 270° is the minimum period of the geometrical intake stroke from intake top dead center (TDC) to bottom dead center (BDC). Yes, it is necessary to set it at least higher than this in order to effectively inhale. On the other hand, the upper limit of 320° is I9! where two consecutive working chambers of one cylinder communicate through the intake boat! In other words, this is to prevent the opening period of each working chamber from lapping, and the upper limit of the opening period is 360 degrees due to the substantial opening and closing of the intake boat by the side surface of the rotor.
°, but the side seal attached to the side of the rotor has J
:The opening period is about 40 degrees larger than that, and in order to avoid the wrap of the small opening period on this side seal, it is necessary to suppress the intake bow period by 1 to 21 degrees to 32 degrees or less. be. By covering the opening [1 brightness is set to 320° or less, communication between the intake working chamber and the subsequent exhaust working chamber is prevented through the minute gap between the rotor side surface on the outside of the lead seal and the inner peripheral surface of the side housing. Therefore, it is possible to prevent exhaust gas from being brought into the intake working chamber during low loads and low rotations such as idling, and to ensure stable combustion. This is the actual opening/closing period of the intake ball l~ by the side of the rotor, and not by the side seal.This is the effective opening/closing period of the intake ball l~ by the side seal.This is due to the fact that the outside of the lead seal This is because the minute gap does not substantially have the influence 1.

In addition, regarding the setting of the downstream position of the throat 1 hell valve of the expansion chamber that exits the communication path to the right in the above settings, the existence of the throat 1 to 1 hell valves acts as a resistance to the propagation of pressure waves (compression waves and expansion waves), so it must be This is to prevent pressure waves from attenuating and propagate them effectively.

Furthermore, the passage length 91 between the expansion chamber and the intake bow 1 of each cylinder in the above setting C is 5000 to 700 Qrpm.
This is set to obtain a unique intake pulsation effect at high engine speeds. 9, +-(θ-θj)
... This is a value calculated from the formula of (I>. That is, in the above formula, the intake port opening period θ-270~
320°, and θ1 is 1111 from just before the intake port is fully closed to when the second pulsation wave of the compression wave, which is the inversion of the expansion wave, is propagated. θ1hi10
0', and therefore (θ-θ1) represents the rotation angle of the eccentric shirt 1 required from the generation of the expansion wave to the propagation of the secondary pulsating wave of the compression wave.

Also, the engine speed is N+ = 5000~700Qr.
pm, 60/36ON+ is 1° rotation (1)
D Represents the time (seconds) required. ζ, C is the propagation velocity of the pressure wave, and C=343 m 2 /s (20° C.).

Further, 2 is a positive order of the pulsating wave and since the secondary pulsation is used, Z=2, and 1/21 represents the reciprocal of the stroke in which the secondary pulsation makes two reciprocations. Therefore, from these values, 9 + ~0
．． It will be 35-0.63m.

Here, in the present invention, the reason why secondary pulsation is used to obtain the intake-specific pulsation effect is that while primary pulsation has the above-mentioned effect, the passage length 91 becomes longer, It is twice as long as the next pulsation, making it difficult to mount on a vehicle.
It also tends to increase intake resistance. On the other hand, in the case of tertiary pulsation, the passage length 91 is 2/3 shorter than that of secondary pulsation (
On the other hand, the above effect against secondary pulsation is about 15-25%.
The degree of this decreases, and the intake resistance does not change much.

For this reason, the purpose is to make the passage length pl as low as λ0 while effectively exerting the unique pulsation effect of the intake air.

Furthermore, the passage length L between the intake ports of the mountain cylinder in the above setting d is 5000 to 7000 rpm/<1.2
Our cll-1 (θ-180-〇+)) X 60 / 360 N 2 X c-(II
) is the value obtained from the formula. That is, in the above equation, the intake port opening period is θ-270 to 320°, 180° is the phase difference between the inner cylinders, and θ0 is the invalid period until the compression wave is generated from the intake port opening. and the period from just before full opening of the intake pommill to full opening during which the opening compression wave is propagated.
Therefore, (θ-180-00) represents the rotation angle of the eccentric shift required from generation of the compression wave at one intake port 1 to propagation to the other intake port. Also, N2 = N+ / (1,25±0.1
25) rpm (N+ is the reference rotation speed of secondary pulsation set between 5000 and 7000 rpm), and 60/
360 N2 is the time required to rotate 1 degree (seconds)
represents. Further, C is the propagation velocity (sound velocity) of the compression wave, and is c=343 m/s at 20°C. Now, as a perfect example,
If N2=4'OOO~5000ppm (1), from these values, 9. + ~0.80~1.71m.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

In Figs. 1 and 2, 1△ and 1B are the first and second cylinders in a side intake port type two-cylinder rotary rev engine, and each cylinder 1A, 1
B is a rotor housing 2 having a two-section inner circumferential surface 2a, and a side housing 4.4 having an intake port 3 located on both sides of the rotor housing 2, which has an intake passage 16a, 16b to be described later. The inside of the casing 5 formed by
The approximately triangular rotor 6 is an eccentric seat 71-7
It is supported by a cylinder for planetary rotational movement, and each cylinder 1A.

The rotor 6.6 of 1B is eccentric 1~Rikushi 17)l~
It has a phase difference of 180° at a rotation angle of 7, and as each [1-Taro rotates, three working chambers 8.8
．． In each cylinder 1Δ, 1B, the intake, compression, explosion, expansion, and exhaust strokes are performed sequentially with a phase difference of 180°. In addition, 9 is an exhaust boat established in 1 coater housing 2 in each cylinder 1A, 1B, 10 and 11 are leading side and trailing side spark plugs, 12 is a "noid seal" attached to the side of rotor 6, and 13 is a 1 pixel seals are mounted on each top of the rotor 6, and corner seals 14 are mounted on both sides of each top of the rotor 6.

The intake boat 3 is opened and closed by the side surface of the rotor 6 (actually the side seal 12), and between the intake boats 3 D
1. ! The IJ interval θ is set in the range of 270 to 320 degrees based on the rotation angle of the eccentric shaft 7.

On the other hand, 15 is an air cleaner, and 16 is Yamaki WJ1Δ.

1B, the main intake passage 16 includes an air flow meter 17 for detecting the amount of intake air, and downstream thereof an air flow meter 17 for controlling the amount of intake air.
A double valve 18 is provided.

The main intake passage 16 has first and second intake passages 1 of equal length.
The first and second intake passages i5a and 161) are branched into the first and second intake passages i5a and 16b, and are connected to the working chambers 88 of the cylinders IA and 1B via the intake boats 3 and 3, respectively.
are each equipped with an electromagnetic valve type fuel injection nozzle 19 that controls the amount of fuel injected according to the output of the air flow meter 17.
19 is arranged, the branch part of the main intake passage 16 is located downstream of the throttle valve 18, and the branch part is located downstream of the first intake passage 16a.
and a second intake passage 161]. The above communication path 20
The passage area of the first section is designed to effectively transmit pressure waves (compression waves due to exhaust interference effect) by reducing their attenuation. It is set to be equal to or larger than the minimum passage area of the second intake passages 16a, 16t). Further, the volume of the expansion chamber 21 is set to 0.5 to 2 times the engine displacement,
If it is less than 0.5 times, the reversal effect between expansion waves and compression waves cannot be obtained, while if it is more than 2 times, the pressure waves will be diffused, and the unique pulsation effect of the intake air will be significantly reduced. Further, the expansion chamber 21 functions as a surge tank for intake air during transient operation such as during engine acceleration or deceleration,
This ensures good responsiveness of the fuel i3+.

Also, the above 1. The passage length 9.1 of the second intake passages 16a, 16ti, that is, the distance from the opening end surface of each intake passage 16a, 161) to the enlarged chamber 21 to the intake bow 1 to 3) to the operating bar 8 is 9.1. Passage length 9+ is 5000 to 7000
Based on the above formula (I), U+ = ((270 ~ 3201 - 100)
0X (5000~7000)X343X1/2X2 - 〇, 35~0. 63 (m).

Furthermore, the passage length between the intake boats 3.3 of the mountain cylinders IA and 1B is the passage length 92 of the communication passage 20 and the passage length 92 of the communication passage 20.
0 downstream of the first and second intake passages 16a, 1611, each passage length 9+, 9+ is added <L=9
2 +2Q+ >, the passage length 1- is set to a value obtained from equation (II) in a rotation range N2 of 1/(1°25±0.125') of the reference rotation speed N1 for obtaining secondary pulsation. ing. In this case, the passage lengths 91 and 92 are each the center length of each passage.

In Fig. 2, 22 is an exhaust passage connected to the exhaust ports 1-0, and 23 is an enlarged manifold for exhaust purification that assists a catalyst device (not shown) interposed in the middle of the exhaust passage 22. be.

Next, the operation of the above embodiment will be explained with reference to FIG. 5.
At high engine speeds of 000 to 7000 ppm, each intake bow I to 3 in the first and q second cylinders 1△ and IB
1st due to the start of inspiration. The expansion waves generated in the second intake passages 16a and 16b are caused by the passage length 91 between each intake boat 3 and the expansion chamber 21 being 5,000 to 7,000 rl) m at high engine speed. 1) 0 by formula
．． By setting it to 35 to 0.63Trl, the first.
2nd intake passages 16a, 16b → expansion chamber 21 (inverted to compression wave, reverse *i > → 1st and 2nd intake passages 16a, 16
b → Intake boat 3 (reflected as an expansion wave) → 1st. Second intake passages 16a, 16b→expansion chamber 21 (reverse to compression wave!)l)→first. Second intake passage 16a.

16b is the secondary pulsating wave of the -C1 compression wave, and τ joint cylinder 1Δ
, 113 is propagated to the intake boat 3 immediately before fully closing. As a result, this secondary pulsating compression wave causes each cylinder to open just before full opening.
Δ, blowback of the intake air from the intake boat 3 of 1B is suppressed and the intake air is forced into the working chamber 8, that is, supercharging is performed. Therefore, each cylinder 1△, due to the supercharging effect due to the unique intake pulsation effect in IB itself, 5000 to 70
The charging efficiency at high engine speeds of 0.00 rpm increases and the output can be improved.

In addition, in the rotation range lower than the secondary pulsation base tp = rotation speed N1 set between 5000 and 7ooorpm,
The frontage compression wave generated in the second intake passage 16b when the intake port 3 of one cylinder, for example, the second cylinder 1B, is opened is based on the passage length between the intake boats 3.3 of the inner cylinder 1Δ and 1B. By setting the predetermined length determined by the above formula (II> in the rotation range of 1/(1,25±0.125) of the rotation speed N1, the communication passage 20 from the second intake passage 16b to the expansion chamber 21 → Via the first intake passage 16a, it is propagated to the intake bow h3 of the first cylinder 1A just before full opening, which has a phase difference of 180°.As a result, this compression wave causes the intake air of the first cylinder 1A just before full opening. The blowback of the intake air from 3 to BO 1 is suppressed, and the intake air is forced into the working chamber B to perform supercharging.

Subsequently, the compression wave generated at the frontage of the intake boat 3 of the first cylinder 1Δ is similarly propagated to the intake boat 3 of the second cylinder IB just before it is fully opened, and supercharging is performed. After that, do the same for cylinder 1△.

Due to the supercharging effect due to the exhaust interference effect between 1B,
: It is possible to improve the output by sufficiently compensating for the filling efficiency during engine rotation, which corresponds to the valley between the secondary pulsation and its tertiary pulsation in the intake-specific pulsation effect.

Therefore, as shown in FIG. 4, each cylinder IA.

1B, at high engine speed (5000 to 700
In addition to the output improvement due to the intake individual pulsation effect (indicated by the broken line) on the intake boat 3 just before full opening at the Intake bow 1 just before full opening when the engine speed is considerably high
-3 to the exhaust interference effect (shown by the solid line) J: Supplements the output decrease in the valley above and improves the output, thereby improving the output from the mid-speed range to the high-speed range of the engine. I can do it. In addition, Fig. 4 shows the intake pulsation effect at 60%.
0Q rpm is set as %i% and the output torque characteristics are shown below.

Since the enlarged chamber 21 having the communication passage 2o is located downstream of the throttle valve 18, the pressure waves are not attenuated by the throttle valve 18, and the exhaust interference effect and intake air pulsation are reduced. The effect can be effectively exhibited, and the supercharging effect can be ensured.

In addition, the supercharging effect due to the air interference effect and the intake air pulsation effect is
Between [1 light interval, first intake passage 16a and second intake passage 16
the position of the expansion chamber 21 having the communication path 2o communicating with b;
In addition, by setting the passage length between the intake boats 3 and 3 of the inner cylinders IA and 1B and the passage length 91 between the expansion chamber 21 and the intake boat 3 as described above,
Since there is no need for a turbocharger, etc., the existing intake system can be slightly installed.
Since the structure is extremely simple, it can be implemented easily and inexpensively, and it is possible to simplify the structure and reduce costs to a large extent.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but also includes various other modifications. For example, in the above embodiment, an example was shown where the present invention was applied to a fuel injection type 1]-taly piston engine, but it goes without saying that the present invention can also be applied to a carburetor type engine. However, in the case of fuel injection type,
The above example! 1.1.1 The fuel injection nozzle 19 is connected to the communication passage 20 (enlarged chamber 21) downstream of the intake passage 16a, l.
Step 6b (Puto J.

This is preferable because it is possible to prevent deterioration in fuel responsiveness caused by the passage length 91 of the intake passages 16a, 16b becoming longer.

Further, in the above embodiment, a case was described in which one system of intake boats 3 was provided for each cylinder 1Δ, 7B, but the present invention provides two systems of intake passages for each cylinder, one for low load and one for high load. It can also be applied when installing. In this case, if both or one of the two intake systems is set to suppress the Jjl air interference effect and the intake air unique pulsation effect. However, if the closing timings of the two systems are different, it is preferable to set the closing timing of the two systems so as to obtain the above effect.

In addition, in order to improve charging efficiency, it is preferable to set the frontage timing of the intake boat of each cylinder to a range of 30 to 60' in terms of the rotation angle of the eccentric 1 helical shaft after top dead center.

In addition, setting the intake/exhaust overlap period in the range of 0 to 20 degrees at a rotation angle of 1 to 11 feet will improve charging efficiency, reduce the amount of taillusion gas brought in, and lower the engine temperature. This is preferable because it can prevent misfires under load.

As explained above, according to the present invention, in a side-intake boat type two-cylinder rotary piston engine,
At high engine speeds of 000 to 7000 ppm, each cylinder's own intake pulsation effect increases the supercharging effect (q), and at the same time, the engine During rotation, the supercharging effect is increased by 1 to compensate for the decrease in output at the valley due to the exhaust interference effect between the cylinders. By making an extremely simple design change, it is possible to improve the efficiency and output from the mid- to high-speed range of the engine, making it easy to implement measures to improve engine output. This is because it can greatly contribute to reducing losses from 1 to 1.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall explanatory diagram, FIG. 2 is an overall schematic diagram of 11g, FIG. 3 is an explanatory diagram showing the intake stroke of the first J5 and the second cylinder, and FIG. is a graph showing the output torque characteristics according to the present invention. 1A...first cylinder, 1B...second cylinder, 2...rotor housing,
2a...Two-section trochoidal inner periphery, 3...Intake boat, 4...Side housing, 5...Casing,
6...Rotor, 7...Eccentric shaft 71~
．． 16... Main intake passage, 16a... First intake passage,
16b... Second intake passage, 18... Throttle valve, 20... Communication passage, 21... Expansion chamber. =211

Claims (1)

[Claims] (1) A substantially triangular rotor runs inside a casing formed by a rotor housing with a two-section trochoidal inner circumferential surface and a side housing with intake ports located on both sides of the rotor housing with intake ports opening into intake passages. A 2-cylinder rotary piston engine is supported by an eccentric shaft and rotates planetarily, and each rotor has a phase difference of 18° at the rotation angle of the eccentric shaft. Eccentric shirt period 1
B. Providing an enlarged chamber having a communication passage that communicates the intake passages of each cylinder downstream of the throttle valve; C5. Under the condition that the length of the intake passage to the intake boat of each cylinder is set to 0.35 to 0.63 TII, the intake bow of each cylinder is Supercharging is performed by inverting the expansion wave generated in the intake passage by the start of intake in step 1- and propagating the second pulsating compression wave of the reflected compression wave to the intake boat just before the joint cylinder is fully opened. On the other hand, when the engine rotates when the trough between the secondary pulsating wave and the tertiary pulsating wave of the compression wave occurs, the compression wave generated in the intake passage during the intake bow 1 to the opening of one cylinder is connected to -F. [-1-Intake Ha of the Talypiston engine.