JPS60256519A - Exhaust port structure in rotary piston engine - Google Patents

Abstract

PURPOSE:To aim at rectifying exhaust gas and reducing exhaust noise, by providing horizontal and vertical partition plates in a port insert which is fitted in an exhaust passage section communicated with an exhaust port and formed in a rotor casing. CONSTITUTION:A through-hole 9 which is composed of a seat hole section 9a extending inward from the outer surface 1b of a rotor housing, an inclined hole section 9b and a parallel hole section 9b nearest to an inner peripheral surface 4, is formed in an exhaust port 7 which is formed in the rotor housing 1, and is fitted therein with a port insert 8 which is provided therein with a horizontal partition plate 16 and a pair of vertical partition plates 17 continuous with the former, those of which divide the insert 8 into three exhaust section passages 20, 22, 24. With this arrangement, just after opening the port, exhaust gas is distributed to the section passages 22, 24 formed in the trailing side and is rectified, thereby exhaust noise is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an exhaust boat structure for a rotary piston engine, in which an exhaust port is opened on the inner circumferential surface of a rotor housing having a trochoidal inner circumferential surface.

(Prior Art) A rotor piston engine generally includes a rotor housing having a trochoidal inner circumferential surface in which a rotor is rotatably housed, and side housings attached to both sides of the rotor housing. form a chamber. This rotor chamber has an appendix seal portion between it and the inner circumferential surface of the rotor housing at the corner vertices of the regular polygonal rotor, whereby a plurality of working chambers are double-sided. The housing is formed with one or more intake ports and one exhaust port opening into the working chamber. The exhaust port of a conventional rotary piston engine is a +qB oval hole having a long axis in the direction of the rotor rotating wheel, and is formed on the trochoid inner peripheral surface of the rotor housing. When the seal part is passed, it opens. Since this exhaust port has a shape having a long axis in the rotational axis direction of the rotor, when the apex seal portion passes through the exhaust port, the open volume of the exhaust port 1-J increases rapidly. For this reason,
There is a problem in that a large amount of exhaust gas builds up in the exhaust port, creating a turbulent flow and rapidly expanding, producing high exhaust noise. In order to solve this problem using the M method, a so-called honeycomb structure has been proposed, in which the exhaust port is composed of a set of three circular boats, two on the leading side and one on the trailing side (Japanese Patent Application Laid-Open No. Showa 56-1/1862
(See public work No. 1).

This structure has three advantages in terms of reducing exhaust noise.
Although this is effective to some extent, it has the drawback of increasing exhaust passage resistance.

In order to deal with the problems of exhaust noise and air resistance, it has been proposed to provide a horizontal partition plate that partitions the exhaust port in the circumferential direction of the rotor housing, that is, in the long sleeve direction of the (1 air boat) above the kidney. According to the proposal, among the exhaust branch passages divided by the horizontal partition 1k,
The trailing side branch passage is further divided into small sections by vertical partitions 1 and 1 to disperse the exhaust energy immediately after the exhaust boat opens L1 and to prevent exhaust turbulence, thereby reducing noise. , the partition plate is placed only on the trailing side of the boat to minimize the increase in passage resistance. Dividing the exhaust passage into small sections using partition plates is effective in reducing exhaust noise, but on the other hand, when exhaust gas passes through the exhaust passage, it comes into contact with the partition plates, A new problem arises in that the temperature decreases, which inhibits the reaction of exhaust gas in the exhaust passage and deteriorates emission performance. In order to avoid such a deterioration in emission performance, it is necessary to minimize the contact area with the partition plate to prevent exhaust gas salt from becoming low F, and to promote the reaction in the exhaust road. Attack on the passage from the port, 1
In order to allow the flame of exhaust gas to naturally extend to the flow side, it is preferable that the exhaust passage not be made as wide as 15J within the range that can avoid a sudden increase in exhaust energy immediately after the ball is opened.

(Objective of the present invention) Therefore, the object of the present invention is to minimize the influence on the reaction of the J-dual exhaust on the road and prevent deterioration of emission performance, while effectively reducing exhaust noise. It is an object of the present invention to provide an exhaust boat structure for a rotary piston engine that can be used.

(Configuration of the present invention) In order to achieve the above object, the present invention is configured as follows. That is, the present invention provides a horizontal partition plate that partitions an air boat opening in the inner circumferential surface of the rotor housing in the circumferential direction of the rotor housing and extends in the flow direction of exhaust gas, and a cylindrical outer cylinder that encompasses the horizontal partition plate. In the exhaust boat structure for a rotary piston engine, the horizontal partition plate includes a boat insert inserted in the exhaust flow direction into an exhaust passage portion formed in a rotor housing.
A vertical partition plate is provided on both sides of the exhaust port, and a vertical partition plate is provided continuously to the horizontal partition plate in a direction perpendicular to the temporary horizontal partition plate, thereby partitioning both corners of the exhaust port on the trailing side and in the exhaust flow direction. It is characterized in that three extending exhaust branch passages are formed.

In order to disperse exhaust energy and prevent exhaust gas from becoming turbulent, partition plates become more effective as they are longer in the direction of exhaust flow and as the number of compartments inside the boat increases. However, on the other hand, the area of contact with the exhaust gas also increases correspondingly, which facilitates the cooling of the exhaust gases and breaks up the flame of the exhaust gases for the reaction in the exhaust road, so that the exhaust passageway The internal reactivity decreases and therefore the emission performance deteriorates.

According to the present invention, horizontal partition plates are provided on both sides of the boat in which the exhaust ports extend in the circumferential direction of the rotor housing, that is, in the direction of the rotation axis of the rotor, and the exhaust ports are provided on both sides of the boat, and the exhaust ports are provided in a continuous manner orthogonal to each horizontal partition plate. A vertical partition plate is provided in the direction. The horizontal partition plate and the temporary vertical partition partition both corners on the trailing side in the rotational direction of the rotor to form two exhaust branch passages extending in the exhaust flow direction, that is, in the thickness direction of the rotor housing. Therefore, when looking at the entire exhaust passage portion of the rotor housing, three exhaust passages are formed.

In this case, there is a relatively large branch passage extending from the trailing edge of the boat to the leading edge between the two extraction passages thrown into the center of the exhaust port, that is, the trailing side corners of the exhaust port, and on the leading side. It is formed.

(Effects of the present invention) As described above, the present invention has a horizontal partition plate and a vertical partition temporary, so that the boat opening iP4', and later the minute 3 rfi path provided on the trailing side. Since the exhaust gas is dispersed and rectified, it is possible to prevent a large amount of exhaust gas energy from concentrating on a single boat, thereby reducing exhaust noise.

In addition, the central pipe of the exhaust port has a large branch passageway extending from the trailing edge to the leading edge, making it possible to keep the contact area of the exhaust gas to a relatively small area, as well as to The flame for promoting the reaction in the exhaust road extending downstream is not divided into small pieces, and therefore reactivity can be maintained well.
Therefore, deterioration of emission performance can be prevented. Note that, in order to naturally extend the flame of the exhaust gas toward the downstream side, it is desirable that the connecting portion between the horizontal partition plate and the vertical partition plate be rounded at least on the downstream side.

(Embodiment) FIG. 1 shows a side boat intake type rotary piston engine Z having an exhaust boat structure according to an embodiment of the present invention. This rotary piston engine Z includes a rotor housing 1 having a trochoid inner circumferential surface 4 and a pair of nide housings 2 that seal both sides of the rotor housing 1, thereby forming a rotor chamber 10 therein. Inside the rotor chamber 10, a roughly triangular rotor 3 is arranged. ．． 7 o 9.4 o-months, □yo. , 7, back 22
, , (The apex portion 30 is provided with an apex seal in sliding contact with the inner circumferential surface 4 of the rotor 1. As a result, the working chamber 27a is formed by the rotor housing 1 and the side surface of the rotor 3.
, 27b and '2.7c are formed, respectively. rotor 3
is supported by an eccentric shaft 5 and rotates in the direction indicated by the arrow in FIG. According to the rotation of the rotor 3, the working chamber 2
The volumes of 7a, 27b and 27C change periodically, thereby forming the intake, compression, explosion and exhaust strokes.

In FIG. 1, the state shown in the working chamber 2.7a is at the bell stage of the explosion stroke, at the beginning of the exhaust stroke.

The working chamber 27b is in the intake stroke, and the working chamber 27r is (
It's on the upper line. The nide housing 2 is equipped with an intake boat 6 that opens into the working chamber 27b during the intake stroke, and introduces the air-fuel mixture into the working chamber 27b. The rotor housing 1 is provided with an exhaust port 7, and the exhaust port 7 is connected to the working chamber 2 during the exhaust stroke.
Combustion gas is discharged from 7a.

Referring to FIG. 2, the exhaust port 7 is provided with a through hole 9 provided in the rotor housing 1, and the through hole 9 opens into the rotor chamber 10 through a mouth edge 7a. At the same time, it passes through the rotor housing l in the thickness direction.

The through hole 9 includes a large portion 9a extending inward from the outer surface 1b of the rotor housing, a large inclined portion 9b extending further inward from the large portion 9a, and a parallel large portion 9b closest to the inner circumferential surface 4. It is composed of a portion 9c. Referring to FIG. 4, the mouth edge 7a has a rectangular shape with curved corners. The parallel major portion 9c of the through hole 9 has a shape substantially similar to the mouth edge 7a. At its inner end, that is, on the rotor chamber 10 side, the large inclined portion 9b has a width in the direction of the rotational axis of the rotor 3 that is slightly larger than the mouth edge 7a, and a length perpendicular to the mouth edge 7a. As a result, a step S1 is formed on the trailing side and a step S2 is formed on the leaping side.The major slope portion 9b has a leading side facing outward. The hole portion 9a is larger in both width and length than the outer end of the inclined hole portion 9b. As a result, a stepped portion S3 is formed around the periphery. Further, a lining 9d made of a highly heat insulating ceramic material is disposed on the inner circumferential surface of most of the slope. As shown in FIG. 2, the boat insert 8 is inserted into the through hole 9.
It is designed to be inserted into. Referring to Figure 3,
The port insert 8 has a large part 9a and a large part 9b.
It is provided with a flange part 11 that can be seated on a stepped part S3 formed between the two. This port insert 8 is
An inclined cylindrical portion 12 extending from the collar portion 11 is formed. This inclined cylindrical portion 12 has a shape corresponding to the inclined major portion 9b of the MiffI hole 9. In this case, the inclined cylinder portion 42 is configured such that a clearance G exists between the inclined cylinder portion 42 and the large inclined portion 9b. A plurality of openings 12b are provided on the downstream side of the inclined cylindrical portion 12, whereby a portion of the exhaust gas flows between the mouth edge portion 7a and the port insert 8, and the above-mentioned clearance G is Pass by, Beau 1-
It flows to the flow side of inserter 1 and inserter 3. This results in
Most of the periphery of the boat insert 1-8 is interposed between the port and the rotor housing 1 as an exhaust gas region 1, and direct heat transfer from the boat insert 8 to the rotor housing is restricted. Furthermore, most of the slope 9b of the through hole 9
Since a highly insulating lining 9d is disposed on the inner peripheral surface of the rotor housing, heat transfer from the port insert 8 to the rotor housing is further restricted.

Inside the port insert 8, the width direction of the insert,
That is, it includes a horizontal partition plate 16 that extends in the horizontal direction and a pair of vertical partition plates 17 that are continuous with the horizontal partition plate 16 and extend in a direction perpendicular to the direction in which the horizontal partition plate 16 extends. Inside the insert 8, there is a first exhaust passage 2 that expands from the center on the trailing side to the leading side.
0, and a second exhaust passage 22 and a third exhaust passage 24 are formed on both sides of the trailing side. This connection between the horizontal partition plate 16 and the vertical partition plate 17 is rounded. The horizontal partition plate 16 and the vertical partition plate 17 extend outward from the collar portion 1j, that is, in the exhaust gas outflow direction, and extend inwardly along the inclined cylindrical portion 12, and further extend from the inner end of the inclined cylindrical portion 12. It protrudes from the hole and reaches the mouth edge 7a of the through hole 9. And the tips 16a, 17a
reaches a position extremely close to the inner circumferential surface 4 of the rotor housing 1. Further, the rear ends 16b, 17b of the horizontal partition plate 16 and the vertical partition plate 17 reach the rear end 1b of the insert 8.

The trailing side of the pJj oblique cylinder portion 12 extends inward from the tip 12a, that is, toward the inner circumferential surface 4, and is bent toward the leading side at the tip. A screen plate 15 is formed. Therefore, the 1-railing side opening end 20a of the first exhaust branch passage 20 is more similar to the trailing side 1'' ends 22a, 24a of the second and third exhaust passages 22.24 in the rotor housing circumferential direction of the screen plate 15. It will be located slightly closer to the leading side.

Next, the operation of the rotary piston engine Z of the illustrated embodiment will be explained. When the engine Z is operated, the rotor 3 connects the apex portions 30 attached to the three ridges to the inner periphery of the trochoid 4, respectively. While rotating, the rotor 3 freely rotates around the eccentric shaft 5, and while the rotor 3 rotates once, intake air is sucked into the working chamber from the intake boat 6, pressurized, and then combusted and exploded to release the combustion gas (exhaust gas). Exhaust from exhaust port 7.

By the way, the apex portion 30
81' passes through the exhaust port 7 from the trailing side to the leading side, and the exhaust port 7 is connected to the apex portion 30.
Trailing side working chamber (number 2 in Fig. 1 and Fig. 2)
7b), the trailing side working chamber 2
The high pressure and high temperature exhaust gas in 7b is opened 1] Exhaust port 7
from there through the exhaust passage to the outside.

In this case, in this embodiment, the exhaust port 7 is divided to form the leading side exhaust passage (first exhaust passage) 20 and the second and third exhaust passages 22,24.
In particular, even immediately after opening when the exhaust gas pressure is high (exhaust energy is large), the exhaust gas is discharged in separate flows to the first, second, and third exhaust branch passages 20, 22, and 24, respectively.
Rapid expansion of the exhaust gas is prevented and exhaust energy of the exhaust gas is dispersed, and the horizontal partition plate 16 and the vertical partition plate 17 act as a type of rectifier 7, so that the exhaust gas flow is rectified. Therefore, the vibration noise is small and the exhaust noise of the engine Z is reduced.

Furthermore, in this embodiment, the partition plates 16 and 17 are arranged at both corners on the trailing side, and a relatively large first exhaust passage 20 is formed in the center, so that the exhaust gas is not directed to the partition plates. The number of contact parts can be reduced, thereby suppressing a drop in the temperature of the exhaust gas, and also allowing the flame of the exhaust gas to be maintained naturally without being split. In addition, there is a gas circulation area around the port inlet, and a heat insulating lining 9d is placed on the most inclined part 9b of the exhaust passage.
7. Dissipation into the rotor housing 1 via the exhaust cuff, (7) heat treatment, the cape 3□6-1, and the bottom 18 can be restricted as much as possible. With these, it is possible to maintain good reactivity of exhaust gas in the exhaust passage, and therefore, it is possible to prevent deterioration of emission performance.

Note that the ratio of the total cross-sectional area of the second and third exhaust branch passages 22.24 to the cross-sectional area of the first exhaust branch passage 20 is preferably 4 or less. This is because the emission performance deteriorates.

Note that the horizontal partition plate 16 and the vertical partition plate 17 are connected to the inclined cylinder part 1.
It is also possible to fix it to the inner surface of 2, but it is sufficient to restrain either one of them. In this way, by fixing the partition plate at one location, thermal stress can be alleviated and cracks can be prevented from occurring at the connection parts.

Furthermore, this exhaust port 7 is connected to a thin horizontal partition plate 16.
When the exhaust passage is partitioned by the vertical partition plate 17, the left side, especially the trailing side, has a unique structure, so it is different from the conventional one. -1 structure. , 4゜, ・ , (The reduction in passage area is small, so the exhaust port'/
When the exhaust gas is fully opened, a sufficient passage area can be secured, and problems such as a decrease in engine output due to an increase in exhaust resistance can be prevented from occurring.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a rotary piston engine according to the present invention, FIG. 2 is a partially enlarged sectional view of the vicinity of the exhaust port of the rotary piston engine of FIG. 1, and FIG. 3 is a sectional view of a boat insert according to the present invention. The perspective view, FIG. 4, is a view taken along the line IV-IV in FIG. 2. l...Rotor housing 2...Side housing 3...Rotor 4...Trochoid inner circumferential surface 6...Intake port 7...Exhaust port 8...Boat insert 9...Through hole■ 0...i:I-Evening room 16...Horizontal partition plate 17...Vertical partition plate

Claims (1)

[Claims] The rotor housing has a horizontal partition plate that defines an exhaust port opening in the inner circumferential surface of the rotor housing in the circumferential direction of the rotor housing and extends in the flow direction of exhaust gas, and a cylindrical outer cylinder that encompasses the horizontal partition plate. In the exhaust boat structure of the rotary piston engine, the horizontal partition plate is provided on both sides of the exhaust port, and the horizontal partition plate is provided on both sides of the exhaust port. A vertical partition plate was provided continuous to the horizontal partition in a direction perpendicular to the plate, thereby dividing both corners of the exhaust port on the trailing side and forming three exhaust branch passages extending in the exhaust flow direction. The rotary piston engine exhaust boat structure is characterized by