JPS5917251B2 - Exhaust port structure of rotary piston engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust port structure for a rotary piston engine, and particularly to an improvement in an exhaust port structure consisting of a plurality of exhaust port groups that start opening at different times.

In general, in low-return piston engines, by making the opening ratio of the exhaust opening more gradual as the rotor rotates, turbulence near the exhaust opening is reduced and unpleasant high-frequency exhaust noise is prevented. For this purpose, it is known to provide a plurality of independent exhaust ports that open at different times.

The present invention aims to further reduce exhaust noise by further improving the above-described type of exhaust port structure.

The present invention will be described in detail below based on embodiments shown in the drawings.

1 to 4 show an exhaust port structure according to an embodiment of the present invention. In the figure, a 1Fi rotor housing is shown, and this rotor housing 1 has a trochoid inner circumferential surface 1a, and on both sides there are side walls. A housing 2 is arranged, and this rotor housing 1 and side housing 2
and form a casing 18.

Further, the rotor Ujifugu 1 is provided with a substantially triangular rotor 3 that is supported by an eccentric shaft (not shown) and rotates planetarily. An apex seal (not shown) is provided to maintain airtightness of the working chamber formed by the circumferential surface 1a and the flank surface 3a of the rotor 3.

Further, the rotor housing 1 is formed with an intake port 4 for introducing working gas into the casing 18 and an exhaust port 5 for discharging the working gas.

By the way, this exhaust port 5 has the following structure.

That is, there are three exhaust openings 6 in the rotano housing 1.
. are set at different times.

In addition, on the exhaust gas downstream side of the exhaust openings 6, 7, 8,
An enlarged quadrant 9 is provided in communication with the exhaust openings 6.7, 8.

Further, three cylindrical members 11, 12, 13 having a plurality of perforations 9 formed on the circumferential surface thereof, and the cylindrical members 11, 12, 1
A mounting flange member 17 having three small-diameter second communication holes 20 that are not continuous with the first communication hole group 14° 15.16 and the cylindrical member 11° 12.13. An insert member 10 is formed,
This insert member 10 is inserted into the enlarged fourth part 9, and the cylindrical member 1
1° 12.13 and the enlarged four-part peripheral wall 9a have a predetermined gap, and this gap communicates with the exhaust manifold (not shown) downstream of the insert member through the second communication hole 20, and each The cylindrical member 11.degree. 12.13 is fitted so that the opening surface at the tip thereof faces each exhaust opening 6, 7.degree.

According to the exhaust port structure of this embodiment configured as described above, the rotor 3 rotates in the direction of arrow A, and the exhaust openings 6,
7 and 8 open sequentially, and exhaust gas flows through each exhaust opening 6, 7, 8.
When the exhaust gas flows down into each of the cylindrical members 11, 12 and 13, a portion of the exhaust gas passes through the perforations 19 made in the circumferential surface of each of the cylindrical members 11, 12 and 13, and enters the enlarged four parts 9. It flows out into the gap between the cylindrical members 11, 12, 13 and the enlarged four-part peripheral wall 9a, further passes through the second communication hole 20 provided in the mounting flange member 17, and flows into the exhaust manifold (not shown) provided downstream of this. ) is emitted into the atmosphere.

Therefore, the pressure of the exhaust gas discharged from each exhaust opening 6, 7, 8 is reduced by the gap in the enlarged four part 9, that is, the gap in this enlarged four part 9 acts as an expansion chamber, so that each The exhaust gas discharged from the exhaust port can be expanded quickly and gradually, thereby effectively reducing exhaust noise.

Note that the second communication hole 20 provided in the mounting flange member 17
can be made most suitable for reducing exhaust noise by appropriately setting the shape (hole diameter) and number through experiments and the like.

As described above, according to the present invention, in the exhaust port structure of a rotary piston engine that includes a plurality of exhaust ports that start opening at different times, a plurality of exhaust openings that open independently in a casing, and a A cylindrical member forming one enlarged portion communicating with the opening on the downstream side, and having a plurality of perforations of the same number as the exhaust opening, a first communication hole group continuous to this cylindrical member, and this cylinder. An insert member is formed of a shaped member and a mounting flange member having a discontinuous second communication hole, and a predetermined gap is maintained between the enlarged four-part peripheral wall and the cylindrical member, and this gap is Since the exhaust port was formed by fitting each cylindrical member so that it communicated with the downstream exhaust manifold through the second communication hole and so that the opening surface at the tip of each cylindrical member faced each exhaust opening, the individual exhaust ports were It is possible to reduce the pressure of the exhaust gas flowing out, thereby further reducing exhaust noise.

[Brief explanation of drawings]

Fig. 1 is a partially sectional side view of a rotary piston engine having an exhaust port structure according to an embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, and Fig. 3 is a cutaway of the main part of Fig. 1. The front view and FIG. 4 are enlarged sectional views taken along the line B--B in FIG. 3. 1...Rotano-Using, 2...Site-no-Using, 3...Rotor, 5...
...Exhaust port, 6,7゜8...Exhaust opening,
9...Four enlarged parts, 9a...Peripheral wall, 10
...Insert member, 11, 12, 13...
... Cylindrical member, 14, 15, 16... First communication hole group, 17... Mounting flange member, 19...
...Drilling, 20...Second communication hole.

Claims (1)

[Claims] 1. Forming a plurality of exhaust openings that open independently in a casing in a rotary piston engine equipped with a plurality of exhaust ports that start opening at different times, and one enlarged recess that communicates with the openings on the downstream side. On the other hand, a cylindrical member having the same number of holes as the exhaust openings and a plurality of holes, a mounting flange having a first communication hole group continuous with the cylindrical member, and a second communication hole discontinuous with the cylindrical member. a predetermined gap is maintained between the enlarged four-part peripheral wall and the cylindrical member, and the gap is connected to the exhaust manifold on the downstream side through the second communication hole. 1. An exhaust port structure for a rotary piston engine, characterized in that the cylindrical members are fitted in such a manner that they communicate with each other and that the opening surfaces at the distal ends of the cylindrical members face the respective exhaust openings.