JPH06221176A - Auxiliary air feeding device for rotary piston engine - Google Patents

Abstract

PURPOSE:To improve the emission characteristics compatible with ensurance of responsiveness to acceleration in a high load area containing a throttle full opening in a low speed area. CONSTITUTION:In a high load area containing a throttle full opening area in a low speed area, so-called substitution air is fed through a substitution air feed passage 16. The feed of substitution air causes substitution of exhaust gas in an exhaust gas operating chamber 5 with fresh air and prevention of bringing of exhaust gas to the exhaust gas operating chamber. Further, the feed of substitution air causes reduction of an intake air temperature, the increase of an intake air temperature, improvement of filling efficiency, and improvement of responsiveness to acceleration. Meanwhile, in a low load area, so-called port air is fed through a port air feed passage 33, combustion stability is improved, and emission characteristics are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auxiliary air supply device for a rotary piston engine.

[0002]

2. Description of the Related Art Conventionally, in a rotary piston engine, in the idle operation region and the light load region, a relatively large amount of exhaust gas is brought into the intake working chamber due to the overlap of intake and exhaust, and this exhaust gas (dilution gas) Since the air-fuel mixture is diluted by this, there is a problem that ignition mistakes occur and combustion becomes unstable, and it is conceivable to supply extra fuel as a countermeasure, but if this is done, then in the idle operation region and light This will deteriorate the fuel consumption characteristics in the load region. .

Therefore, for example, as described in Japanese Patent Laid-Open No. 1-237320, a rotor provided with a planetary rotary motion in a housing having a trochoid inner peripheral surface is provided, and the trailing of the intake port and the leading side of the exhaust port is provided. A first auxiliary air supply passage opening to the side is formed in the housing, and replacement air is supplied through the first auxiliary air supply passage in the idle operation region to prevent carry-in of exhaust gas into the intake working chamber, A second auxiliary air passage opening in the exhaust port is provided, and in the idle operation range,
It is known that the supply of the replacement air is stopped when the engine is cold and the port air is supplied through the second auxiliary air supply passage to improve the combustion stability.

[0004]

[Problems to be Solved by the Invention]
In the high load range including full throttle opening in the low speed range, neither replacement air nor port air is supplied, while on the other hand, in the high load range including full throttle opening in the low speed range,
There is a demand to improve acceleration response.

By the way, as described in Japanese Utility Model Laid-Open No. 1-97041, a port insert divided into two passages is inserted into the exhaust port, and a pressurized air supply source is connected to the passage on the intake working chamber side. Although it is known that the replacement air is supplied, such a port insert cannot be used to independently control the supply of the replacement air and the port air described above. It is difficult to secure a sufficient air flow rate.

It is an object of the present invention to provide an auxiliary air supply device for a rotary piston engine, which achieves both improvement of emission characteristics and ensuring of acceleration response in a high load range including full throttle opening in a low speed range. It is what

[0007]

According to a first aspect of the present invention, there is provided a first auxiliary air supply passage which opens through an opening into an exhaust port provided in a rotor housing to supply first auxiliary air, and the opening. A rotary having a second auxiliary air supply passage located on the leading side for supplying the second auxiliary air into the working chamber, and a switching means for selectively switching the first or second auxiliary air supply passage according to an operating state. In an auxiliary air supply device for a piston engine, an engine load detecting means for detecting an engine load, an engine speed detecting means for detecting an engine speed, an output of the engine load detecting means and an engine speed detecting means, and the switching means are switched. By controlling, in the high load range including the throttle fully open range in the low speed range, the second auxiliary air is supplied through the second auxiliary air supply passage,
In the low load region, the control device is configured to supply the first auxiliary air through the first auxiliary air supply passage. Further, in the invention of claim 2, the engine temperature detecting means for detecting the engine temperature is provided, and the control means receives the output of the engine temperature detecting means and controls the switching of the switching means so that when the engine is cold, The second auxiliary air is supplied through the second auxiliary air supply passage in the high load area including the throttle fully open area in the low speed area, and the first auxiliary air is supplied through the first auxiliary air supply passage in the low load area. Further, in the invention of claim 3, the control means receives the outputs of the engine load detecting means and the engine speed detecting means to control the switching of the switching means, and in the idle operation range, the first auxiliary air supply passage through the first auxiliary air supply passage. Make sure auxiliary air is supplied.

According to a fourth aspect of the present invention, there is provided a first auxiliary air supply passage which is opened through an opening in the exhaust port provided in the rotor housing and which supplies the first auxiliary air, and which is located on the leading side of the opening. Auxiliary air supply for a rotary piston engine having a second auxiliary air supply passage for supplying the second auxiliary air into the working chamber and a switching means for selectively switching the first or second auxiliary air supply passage according to the operating state. A device, wherein a port insert that divides the exhaust port into first and second passages on a trailing side and a leading side is inserted into the exhaust port, and the exhaust passage is connected to the first passage. The first auxiliary air supply passage is opened midway, while the second auxiliary air supply passage is connected to the second passage. And claim 5
In the invention, the rotary piston engine is a multi-cylinder engine, and the second auxiliary air supply passages of the cylinders are communicated with each other through the expansion chamber. According to a sixth aspect of the present invention, the gasket means provided between the rotor housing and the exhaust manifold is arranged between the first gasket arranged around the exhaust port and the circumference of the second passage. A second gasket that is installed, wherein the first gasket is a second
It has higher elasticity than the gasket.

According to a seventh aspect of the present invention, there is provided a first auxiliary air supply passage which is opened through an opening in the exhaust port provided in the rotor housing and which supplies the first auxiliary air, and which is located on the leading side of the opening. Auxiliary air supply for a rotary piston engine having a second auxiliary air supply passage for supplying the second auxiliary air into the working chamber and a switching means for selectively switching the first or second auxiliary air supply passage according to the operating state. A device, which is a port insert inserted into the exhaust port, and a first passage formed in the port insert, which is connected to an exhaust passage and in which a first auxiliary air supply passage is opened. The port insert is formed on the leading side of the first passage and the exhaust port is divided into a trailing side and a leading side by the first passage. A second passage to which the second auxiliary air supply passage is connected, an engine load detecting means for detecting an engine load, an engine speed detecting means for detecting an engine speed, the engine load detecting means and the engine speed detecting means. In response to the output, the switching means is switched to control the second auxiliary air through the second auxiliary air supply passage in the high load region including the throttle fully open region in the low speed region and through the first auxiliary air supply passage in the low load region. 1) A control means for supplying auxiliary air respectively.

[0010]

According to the first aspect of the present invention, the second auxiliary air (so-called replacement air) is supplied through the second auxiliary air supply passage in the high load range including the throttle fully open range in the low speed range,
The exhaust gas in the exhaust working chamber is replaced with the second auxiliary air, which is fresh air, so that the carry-in of the exhaust gas into the intake working chamber is blocked, and the amount of heat carried into the intake working chamber is also reduced due to the reduction of the carry-in amount of the exhaust gas. As a result, the intake air temperature is reduced, the charging efficiency is improved, and the acceleration response is improved. On the other hand, in the low load region, the first auxiliary air (so-called port air) is supplied through the first auxiliary air supply passage,
Combustion stability is improved.

According to the second aspect of the present invention, when the engine is cold, the second auxiliary air is supplied through the second auxiliary air supply passage in the high load range including the throttle fully open range in the low speed range, and the acceleration response is obtained. Is increased. In the low load range, the first auxiliary air is supplied through the first auxiliary air supply passage,
Is reduced.

According to the third aspect of the present invention, in the idle operation range, the first auxiliary air is supplied through the first auxiliary air supply passage, and the emission performance is improved.

According to the invention of claim 4, the exhaust port portion of the rotor housing for supplying the first auxiliary air and the second auxiliary air is formed in a compact and simple structure by the port insert.

According to the fifth aspect of the present invention, the second auxiliary air supply passages of the cylinders are communicated with each other through the expansion chamber, so that there is no variation in the supply amount of the second auxiliary air between the cylinders, and the expansion chamber is expanded. At, the exhaust pulsation is alleviated.

According to the sixth aspect of the present invention, the second gasket having low elasticity is disposed around the second passage of the port insert, which is a portion having high heat resistance and high temperature rise. On the other hand, the first gasket, which has a higher elasticity than the second gasket, has a slightly lower heat resistance but an excellent sealing property, and is disposed around the exhaust port, which is a portion where the temperature rise is low.

According to the seventh aspect of the present invention, in the high load range including the throttle fully open range in the low speed range, the second auxiliary air is supplied through the second passage of the port insert, and the exhaust gas in the exhaust working chamber is fresh. Is replaced by and the carry-in of exhaust gas into the intake working chamber is prevented. In the low load region, the first auxiliary air is supplied through the first passage of the port insert to improve the combustion stability.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings.

In FIG. 1 showing a schematic structure, 1 is an engine body of a rotary piston engine, and its casing has rotor housings 2 and 2 having a trochoid inner peripheral surface.
And a pair of side housings 3 and 3 (only one of the side housings is shown). The rotors 4 and 4 are housed in such a casing so as to make a planetary rotational movement.

Three working chambers 5, ... Are defined between the casing and the rotors 4, 4, respectively. In these three working chambers 5, ..., the rotors 4, 4 are formed on the inner peripheral surface of the rotor housing 2. The volume changes due to the planetary rotational movement in the clockwise direction while sliding with respect to the intake, compression, explosive expansion, and exhaust strokes.

Reference numeral 11 is a main air passage to which pressurized air is supplied by an air pump (not shown), and a first opening 13 which is opened and closed by a first valve body 12 is formed. The first opening 13 is branched via the check valve 14 and the expansion chamber 15 (tank), and is opened to the leading side from the opening of the port air supply passage 33, which will be described later, and the working chamber 5 (exhaust working chamber) of each cylinder. A replacement air supply passage 16 (second auxiliary air supply passage) for supplying replacement air is connected to. Therefore, the expansion chamber 16 communicates with the replacement air supply passage 16 of each cylinder so that exhaust pulsation is not transmitted to the check valve 14 when the replacement air is not supplied. 14. The reliability of the air pump and the like is ensured, and the variation of the replacement air supply amount does not occur between the cylinders.

The first valve body 12 is constructed so as to be opened and closed by a first diaphragm device 18.
The diaphragm device 18 excites the first solenoid valve 19 (O
N) to displace the valve body 19, and the working chamber 18b in which the spring 18a is compressed is communicated with the boost tank (not shown) through the communication passage 20.
8c is displaced to open the first opening 13.

Further, second to fourth openings 21A, 21B, 22 are formed on the downstream side of the first opening 13, and the second to fourth openings are formed.
The openings 21A, 21B, 22 have the second and third valve bodies 23, 2
4 is configured to be opened and closed. The second and third valve bodies 23 and 24 are the second and third diaphragm devices 2
5, 26 connected to the second and third diaphragm devices 2
Reference numerals 5 and 26 energize the second and third electromagnetic valves 27 and 28 to displace the valve bodies 27a and 28a, and the negative pressure passage 30 in which the control valve 29 is provided in the middle of the intake manifold (not shown). The negative pressure is introduced into the working chambers 25a and 26a by connecting the valve to the second chamber 25a and 26a, and the displacement of the diaphragms 25b and 26b causes the second pressure against the spring force of the springs 31 and 26c.
Also, the third valve bodies 23, 24 are displaced.

The second opening 21A is connected to branch passages 34a, 34a connected to the respective cylinders of the exhaust passage 34 through a port air passage 33 having a check valve 32 interposed therein and opening through the opening in the exhaust port. The 3rd opening 21B is connected to the split air passage 37. Then, when the second opening 21A is closed and the third opening 21B is opened by exciting the second electromagnetic valve 27, split air is supplied through the split air passage 37, and the second opening 21A is demagnetized by demagnetizing the second electromagnetic valve 27. Is opened and the third opening 21B is closed, the port air is supplied through the port air passage 33.

On the other hand, the fourth opening 22 is connected to a relief silencer (not shown) through the passage 35, and when the fourth opening 22 is opened by the excitation of the third solenoid valve 28, the secondary air is forced. It is supposed to be relieved.

The portion provided with the second valve body 23 is connected to a split air passage 37 in which a check valve 36 is interposed, and air from the air pump is sent to the exhaust passage 34 through the split air passage 37. The catalyst of the provided catalytic converter 38 is supplied in order to enhance its exhaust gas purification function.

Further, the upstream side of the second opening 21A and the port air passage 33 are connected by a leakage passage 40 in which a fourth solenoid valve 39 is provided, and the leakage passage 40 is communicated by the excitation of the fourth solenoid valve 39. Then, a predetermined amount of port air leaks.

Reference numeral 41 is a control unit (control means)
Then, as shown in FIG. 2, an engine speed signal N from an engine speed sensor as an engine speed detecting means,
A throttle opening signal TV0 from an engine load sensor as an engine load detecting means, a cooling water temperature signal T from an engine cooling water temperature detecting sensor as an engine temperature detecting means, and a boost pressure signal P from a boost pressure sensor as an engine load detecting means. In response to this, the first to fourth electromagnetic valves 19, 27, 28, 40, which function as switching means, are switched and controlled.

Specifically, in the engine warm state, as shown in FIG. 3, in the region R11 which is a high load region including the throttle fully open region in the low speed region, the replacement air supply passage 1 is provided.
The replacement air is supplied through 6, so that the filling efficiency is enhanced and the acceleration response is enhanced. In the low load region R12, port air is supplied through the port air supply passage 33, and C
It is designed to positively purify O and HC. In the region R13 which is a low load region in the high speed region, CO, H
Split air is supplied through the split air passage 37 in order to efficiently purify C and NOx. In addition, in the region R14, split air is supplied while leaking port air in order to improve the traveling performance.
Further, the air pump is stopped in the region R15 which is a high speed region.

On the other hand, in the engine cold state, as shown in FIG.
As shown in, in the region R21 which is the high load region including the throttle fully open region in the low speed region, the displacement air is supplied through the displacement air supply passage 16 to enhance the acceleration response, while in the region R22 which is the low load region. , The combustion temperature of the engine is low and CO and HC are easily generated.
Port air is supplied through 3. Then, in the region R23 which is a high speed region, the air pump is stopped.

Therefore, in the idle operation range, the port air is supplied through the port air supply passage 33, and the emission performance is improved.

Next, a specific flow of processing by the control unit will be described with reference to FIG.

First, when the engine is started by turning on the ignition or the like, it is determined whether or not the engine cooling water temperature T is equal to or higher than a set temperature T1 in order to determine whether it is a warm state or a cold state (step). S1). If the engine cooling water temperature T is equal to or higher than the set temperature T1, it means that the engine is warm.
Since the control is performed based on FIG. 3, the engine speed is the first
It is determined whether or not it is equal to or less than the second set rotational speed N2 which is larger than the set rotational speed N1 (step S2). If the engine speed N is less than or equal to the second set speed N2, it is determined whether the throttle opening TV0 is greater than or equal to the first set opening TV01 (step S3). If the throttle opening TV0 is greater than or equal to the first set opening TV0, whether the engine speed N is less than or equal to the first set speed N1 (<N2) or whether the boost pressure P is less than or equal to the set pressure P1. Is determined (step S4).

If the engine speed N is the first set speed N1 or less, or the boost pressure P is the set pressure P1 or less, the region R11 is reached, so that the replacement air supply mode is entered (step S5). ), Return.

If the engine speed N is not lower than the first set speed N1 and the boost pressure P is not lower than the set pressure P1, the throttle opening TV0 is set to the second set opening TV02.
(> TV01) It is determined whether or not it is above (step S6).
), If it is equal to or greater than the second set opening TV02, it is in the region R13, and therefore the split air supply mode is set (step S7).
), If it is not equal to or more than the second set opening TV02, it is in the region R14, so the split air and port air leakage supply mode is set (step S8), and the process returns.

In step S3, the throttle opening T
If V0 is not equal to or larger than the first set opening TV01, it is the region R12, and the port air supply mode is set (step S9).
), Return.

At step S2, the engine speed N
If is not less than the second set rotational speed N2, it is the region R15, so the air pump stop mode is set (step S10), and the process returns.

If the engine cooling water temperature T is not equal to or higher than the predetermined temperature T1 in step S1, it means that the engine is in a cold state and the control is performed based on FIG. 4, and whether the engine speed N is the second set speed N2 or less. It is determined whether or not the boost pressure P is equal to or higher than the set pressure P1 (step S12) if the second set rotational speed N2 or lower (step S12). Since it is R21, the replacement air supply mode is set (step S5). If it is not equal to or higher than the set pressure P1, the region R22 is set, so that the port air supply mode is set (step S9) and the process returns.

On the other hand, if it is determined in step S11 that the engine speed N is not less than the second set speed N2, the region R23 is set.
Therefore, the air pump stop mode is set (step S1
0), return.

The states of the first to fourth solenoid valves 19, 27, 28, 40 in each of the above modes are as shown in Table 1 below.

[0040]

[Table 1] Next, a port insert is used to form the replacement air supply passage 16 and the port air supply passage 33, which will be described.

As shown in FIG. 6, in the rotor housing 2, an exhaust port 2a is formed on the trailing side of an intake port (not shown). Inside the exhaust port 2a, the exhaust port located on the leading side is located. The first passage 51 connected to the branch passage 34a of the exhaust passage 34 downstream of 2a and the working chamber 5 arranged on the trailing side so as to cover the first passage 51.
The port insert 5 that is divided into two passages, a second passage 52 that communicates with the replacement air supply passage 16 that supplies pressurized air for scavenging (so-called replacement air) into the (exhaust gas working chamber)
3 (see FIGS. 7 and 8) is inserted and mounted. The port insert 53 is made of a tubular member, and is inserted and mounted from the outside toward the working chamber 5 (exhaust working chamber) side.

A communication hole 2b for supplying port air is formed in the rotor housing 2, and the port air is supplied into the first passage 51 through the communication hole 2b and the opening 53a of the port insert 53.

On the other hand, in the second passage 52, as described above,
An air pump (not shown) is connected through a replacement air supply passage 16 so as to supply replacement air for scavenging into the working chamber 5 (exhaust working chamber), and is integrally formed with the port insert 53. The air nozzle portion 54 is provided.

The air nozzle portion 54 faces the working chamber 5 (exhaust working chamber), and its nozzle hole is formed upward toward the intake short shaft portion. Also, if the replacement air is supplied at high load to improve the filling efficiency,
Since the exhaust pressure of the replacement air supply unit is high and the differential pressure at the air nozzle portion 54 of the port insert 53 is small, the flow velocity of the replacement air is reduced. I try to increase the flow velocity. As a result, the dilution substitution ratio in the high load region is increased and the filling efficiency is improved without deteriorating the emission performance. In the replacement air supply passage 16, it is possible to reduce the pressure loss from the air pump to the air nozzle portion 54 and increase the differential pressure at the air nozzle portion 54 to increase the discharge flow velocity (flow rate) of the replacement air. If this is done, the amount of fresh air flowing to the catalytic converter side will decrease, and the emission performance will deteriorate, which is not preferable.

Then, with respect to the rotor housing 2, the expansion chamber 15 for communicating the replacement air supply passage 16 of each cylinder with each other.
Exhaust manifold 55 integrally formed with
(See FIGS. 9 and 10) are the first and second gaskets 5.
The first gasket 56 composed of Nos. 6 and 57 is connected via the gasket means that is formed to have higher elasticity than the second gasket 57 (see FIG. 11).

The first gasket 56 is shown in FIG. 12 and FIG.
As shown in FIG.
A hole 56a for a) is formed, and the core material 56b is formed.
In contrast, mica sheet 56c (mica), heat-resistant steel plate 56d
(Inconel) is provided and they are made of stainless steel plate 56e.
Wrapped in. On the other hand, the second gasket 57 is a laminated steel gasket, and as shown in FIGS. 14 to 16, has a hole 57a for the second passage 52 of the port insert 53, and has stainless steel plates 57b, 57c, 57d.
Are laminated.

That is, since the periphery of the second passage 52 is surrounded by high-temperature exhaust gas, and the exhaust manifold 55 and the port insert 53 both reach high temperatures, the temperature of the second gasket 57 also rises. It uses a highly rigid gasket with excellent heat resistance and low stretchability. On the other hand, since the first gasket 56 contacts the rotor housing 2, the second gasket 5
Since the temperature is lower than in No. 7 and the heat resistance is small, a low-rigidity gasket having a high stretchability, which has a slightly low heat resistance but is excellent in sealing property, is used. As a result, between the exhaust manifold 55 and the rotor housing 2, the sealing performance around the second passage 52 through which the replacement air supply passage 16 communicates can be secured without deteriorating the sealing performance around the exhaust port 2a. .
Incidentally, 53b is a groove into which the second gasket 57 is fitted.

Therefore, when the top of the rotor 4 passes through the exhaust port 2a as the rotor 4 rotates, the expansion working chamber, which had been in the expansion stroke until then, shifts to the exhaust stroke and becomes a new exhaust working chamber. The gas after combustion inside thereof is discharged to the outside through the first passage 51, the branch passage 34a and the exhaust passage 34. At the same time, the replacement air pressurized by the air pump is supplied from the air nozzle portion 53 through the second passage 52 into the exhaust working chamber. At this time, the replacement air is blown out from the injection hole of the air nozzle portion 53 toward the short air supply shaft portion of the intake working chamber and toward the side housing 3 sides on both sides of the rotor housing 2. For this reason, the dilution gas staying in the vicinity of the intake short shaft portion in the exhaust working chamber is diluted while being replaced by the replacement air and is sequentially discharged from the exhaust passage 34 to the outside, so that the scavenging is efficiently achieved. It

As a result, when the exhaust stroke of the exhaust working chamber is completed with the rotation of the rotor 4 and the exhaust working chamber is changed to the new intake working chamber after the transition to the intake stroke.
The amount of dilution gas brought into the intake working chamber is reduced as much as possible.

With the above arrangement, the replacement air supply passage 16 and the port air supply passage 33 can be independently provided in one port insert 53.
The air supply amounts of the replacement air and the port air can be controlled independently.

Therefore, during start-up and warm-up, port air can be supplied from the port air supply passage 33 to reduce HC, and during idle operation, port air can be supplied through the port air supply passage 33 to improve emission performance. It is possible to improve, and even when the load is light,
Port air can be supplied from the port air supply passage 33 to improve combustion stability.

Further, in the high load range including the throttle fully open range in the low speed range, the replacement air is supplied from the replacement air supply passage 16 to replace the exhaust gas (dilution gas) with fresh air, thereby filling the exhaust gas. It is possible to improve efficiency and acceleration response. In this high load region, the exhaust pressure is relatively high, and when the replacement air is supplied, the load of the air pump increases as the flow rate increases, but the torque increase due to the replacement air increases more than the increase in the load. Can be set as described above, which is also advantageous in terms of fuel efficiency.

[0053]

As described above, the invention of claim 1 supplies the second auxiliary air (so-called replacement air) through the second auxiliary air supply passage in the high load region including the throttle fully open region in the low speed region. Therefore, in the high load range including the throttle fully open range in the low speed range, the exhaust gas in the exhaust working chamber is replaced by the second auxiliary air supplied through the second auxiliary air supply passage to exhaust the exhaust gas into the intake working chamber. It is possible to reduce the amount of heat introduced into the intake working chamber due to the reduction in the amount of exhaust gas brought in, to lower the intake air temperature, to enhance the charging efficiency, and to enhance the acceleration response. Further, in the low load region, since the first auxiliary air (so-called port air) is supplied through the first auxiliary air supply passage, the combustion stability can be improved.

According to the second aspect of the present invention, as described above, when the engine is cold, the second auxiliary air is supplied through the second auxiliary air supply passage in the high load range including the throttle fully open range in the low speed range. Therefore, even when the engine is cold, it is possible to improve the acceleration responsiveness in the high load range including the throttle fully open range in the low speed range. First in the low load range
Since the first auxiliary air is supplied through the auxiliary air supply passage, HC can be reduced.

According to the third aspect of the present invention, the first auxiliary air is supplied through the first auxiliary air supply passage in the idle operating range, so that the emission performance in the idle operating range can be improved.

According to the invention of claim 4, the first auxiliary air and the second auxiliary air are provided.
Since the exhaust port portion of the rotor housing for supplying the auxiliary air is constituted by the port insert, the structure is compact and simple.

According to the fifth aspect of the present invention, the second auxiliary air supply passage of each cylinder is made to communicate with each other through the expansion chamber, so that it is possible to eliminate the variation in the supply amount of the second auxiliary air between the cylinders. It is also possible to prevent exhaust pulsation from being transmitted through the second auxiliary air supply passage when the replacement air is not supplied by the expansion chamber.

According to the sixth aspect of the present invention, the temperature of the second gasket having low elasticity is increased by increasing the temperature of the first gasket having elasticity higher than that of the second gasket with respect to the periphery of the second passage having a high temperature increase. Since the exhaust manifold and the rotor housing are respectively disposed around the exhaust port, the sealing performance around the exhaust port is ensured without deteriorating the sealing performance around the second passage between the exhaust manifold and the rotor housing. be able to.

In the seventh aspect of the invention, the second auxiliary air is supplied through the second passage of the port insert in the high load range including the throttle fully open range in the low speed range. Since it is possible to prevent gas from being brought in and to supply the first auxiliary air through the first passage of the port insert in the low load range, it is possible to improve combustion stability.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an auxiliary air supply device for a rotary piston engine.

FIG. 2 is an explanatory diagram of a control unit.

FIG. 3 is a diagram showing a control map in a warm state.

FIG. 4 is a diagram showing a control map in a cold state.

FIG. 5 is a flowchart showing a control flow of a control unit.

FIG. 6 is a cross-sectional view showing a schematic configuration of a portion provided with a port insert.

FIG. 7 is a vertical sectional view of the port insert.

8 is a sectional view taken along line VIII-VIII in FIG.

FIG. 9 is a partial cross-sectional view of an exhaust manifold.

10 is a cross-sectional view taken along line XX of FIG.

11 is a diagram as viewed in a direction along a line XI-XI in FIG.

FIG. 12 is a front view of a first gasket.

13 is a sectional view taken along line XIII-XIII in FIG.

FIG. 14 is a front view of a second gasket.

15 is a sectional view taken along line XV-XV in FIG.

16 is a sectional view taken along line XVI-XVI in FIG.

[Explanation of symbols]

 1 Engine body of rotary piston engine 2 Rotor housing 2a Exhaust port 3 Side housing 4 Rotor 5 Working chamber 15 Expansion chamber 16 Replacement air supply passage (second auxiliary air supply passage) 19 First solenoid valve (switching means) 27 Second solenoid Valve (switching means) 28 Third solenoid valve (switching means) 33 Port air supply passage (first auxiliary air supply passage) 34 Exhaust passage 40 Fourth solenoid valve (switching means) 41 Control unit (control means) 51 First passage 52 2nd passage 53 Port insert 55 Exhaust manifold 56 1st gasket 57 2nd gasket

Claims (7)

[Claims] 1. A first auxiliary air supply passage that opens through an opening into an exhaust port provided in a rotor housing and supplies first auxiliary air, and a second auxiliary air supply passage that is located on the leading side of the opening and is located in a working chamber. An auxiliary air supply device for a rotary piston engine, comprising: a second auxiliary air supply passage for supplying auxiliary air; and a switching means for selectively switching the first or second auxiliary air supply passage according to an operating state. Engine load detecting means for detecting the engine speed, engine speed detecting means for detecting the engine speed, and switching control of the switching means in response to the outputs of the engine load detecting means and the engine speed detecting means to fully open the throttle in the low speed range. The second auxiliary air is supplied through the second auxiliary air supply passage in the high load area including the air conditioner, and the first auxiliary air is supplied through the first auxiliary air supply passage in the low load area. An auxiliary air supply device for a rotary piston engine, comprising: a control means for supplying air respectively. 2. An engine temperature detecting means for detecting an engine temperature, wherein the control means receives the output of the engine temperature detecting means and controls the switching means to switch the throttle temperature in a low speed range when the engine is cold. The second auxiliary air is supplied through the second auxiliary air supply passage in the high load area including the fully open area, and is first in the low load area.
The auxiliary air supply device for a rotary piston engine according to claim 1, wherein the first auxiliary air is supplied through the auxiliary air supply passages. 3. The control means receives the outputs of the engine load detecting means and the engine speed detecting means and controls the switching of the switching means so that the first auxiliary air is supplied through the first auxiliary air supply passage in the idle operation range. The auxiliary air supply device for a rotary piston engine according to claim 1 or 2, wherein the auxiliary air supply device is provided. 4. A first auxiliary air supply passage which opens through an opening into an exhaust port provided in the rotor housing and supplies the first auxiliary air, and a second auxiliary air supply passage which is located on the leading side of the opening and is located inside the working chamber. An auxiliary air supply device for a rotary piston engine, comprising: a second auxiliary air supply passage for supplying auxiliary air; and a switching means for selectively switching the first or second auxiliary air supply passage according to an operating state, A port insert that divides the exhaust port into first and second passages on the trailing side and the leading side is inserted into the exhaust port, and the first passage is connected to the exhaust passage and is connected to the first passage midway.
An auxiliary air supply device for a rotary piston engine, wherein the auxiliary air supply passage is opened, while the second passage is connected to a second auxiliary air supply passage. 5. The auxiliary air supply device for a rotary piston engine according to claim 4, wherein the rotary piston engine is a multi-cylinder engine, and the second auxiliary air supply passages of each cylinder are communicated with each other through the expansion chamber. 6. Gasket means interposed between the rotor housing and the exhaust manifold are provided for a first gasket arranged around the exhaust port and a second gasket arranged around the second passage. 6. The auxiliary air supply device for a rotary piston engine according to claim 4, wherein the first gasket is formed to have higher elasticity than the second gasket. 7. A first auxiliary air supply passage which opens through an opening into an exhaust port provided in the rotor housing and supplies first auxiliary air, and a second auxiliary air supply passage which is located on the leading side of the opening and is located in the working chamber. An auxiliary air supply device for a rotary piston engine, comprising: a second auxiliary air supply passage for supplying auxiliary air; and a switching means for selectively switching the first or second auxiliary air supply passage according to an operating state, A port insert inserted into the exhaust port; a first passage formed in the port insert, to which an exhaust passage is connected, and a first auxiliary air supply passage opened in the middle; The second auxiliary is formed so as to be located on the leading side of the first passage and divide the exhaust port into a trailing side and a leading side with the first passage. A second passage to which an air supply passage is connected, an engine load detecting means for detecting an engine load, an engine speed detecting means for detecting an engine speed, an output of the engine load detecting means and the engine speed detecting means, and the switching. By switching the means, the second auxiliary air is supplied through the second auxiliary air supply passage in the high load area including the throttle fully open area in the low speed area, and the first auxiliary air is supplied through the first auxiliary air supply path in the low load area. An auxiliary air supply device for a rotary piston engine, comprising: a control means for supplying the auxiliary air.