JPH0311375Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a casing for a rotary piston engine, and more specifically, to a connecting surface for connecting adjacent cooling water passages to a mating surface of a boss portion for insertion of a tension bolt. This invention relates to a casing in which grooves are formed. This is used in the field of rotary piston engines in which a rotor housing and a side housing are bolted together with a seal member in between.

[Prior Art] The casing of a rotary piston engine consists of a rotor housing having a trochoidal inner peripheral surface and side housings fastened to both sides of the rotor housing using tension bolts. Since such a casing is formed with a cooling water passage through which cooling water flows in the direction of the output shaft, there is a wall around the inner and outer walls of the mating surfaces of both housings to prevent leakage of cooling water. A sealing member is interposed.
For this purpose, a seal groove for fitting the mating surface is generally formed on one side of the mating surface.

Incidentally, in a rotary piston engine, the heat load acting on the casing is not uniform over the entire circumference, and a hot zone from the position where the spark plug is installed to the point where the exhaust port is opened is exposed to high temperatures. In particular, if an exhaust manifold is provided near the exhaust port, the heat load on the casing at that location increases. As a result, the cooling water flowing through the cooling water passage may locally insufficiently cool the casing, which may impair engine performance.

[The problem that the idea aims to solve]

In order to solve the above-mentioned problems, a device in which the cooling effect of that part is enhanced is described in, for example, Japanese Utility Model Application Publication No. 55-83225. this is,
The inner wall near the exhaust port has a thinner wall structure than the inner wall at other locations. As a result,
Cooling of areas with poor heat dissipation can be actively strengthened by the exhaust manifold, and some results can be obtained.

However, with such a structure, there is a concern that the strength of the casing may be locally reduced in engines intended for high output. In addition, the sealing member interposed between the mating surfaces is usually made of rubber or the like, which is susceptible to deterioration due to heat. Therefore, if there is a location where the heat load is locally high as described above, there is a problem in that a portion of the sealing member fitted around the inner and outer walls of the mating surface is likely to burn out.

In addition, since the temperature in the hot zone is higher than that in the cold zone, even though there is a cooling effect in the vicinity of the cooling water passage in that zone, the temperature in the vicinity of the boss that integrates the inner and outer walls is The cooling effect may not be sufficient. As a result, deterioration of the sealing member due to heat is unavoidable, and there is a problem that the durability of the sealing member is reduced.
A solution is desired.

By the way, Japanese Utility Model Publication No. 59-159734 discloses that in the vicinity of the attachment part of the seal member in the rotor housing, cooling water is made to flow through the flesh part of the side housing opposite to the attachment part, and the cooling water is also used. Examples of casings are described in which the sealing elements can be cooled.

This is a structure in which a recess is formed in the thick part of the side housing, and the cooling water flowing through the cooling water passage is supplied to the recess, and the cooling water is distributed along the extending direction of the seal member. It is said that In such a case, there are the following problems when casting the side housing. That is, the core sand after casting is difficult to be discharged from the recess and may remain in the recess, and the remaining core sand will have a negative effect on the cooling performance of the seal member. In addition, instead of the above-mentioned recess, a cooling water passage with a closed cross section is sometimes formed as a dedicated cooling water passage in the side housing, facing the mounting position of the seal member, but this is weak in strength. Since a core is used for casting, there are problems with the shape of the core, damage, etc. due to the fluid pressure of the molten metal during casting.

The present invention was developed in view of the above-mentioned problems, and its purpose is to form seal grooves in order to enhance the cooling of the seal member in locations that are difficult to reach and are away from the passage of cooling water flowing through the housing. It is possible to cool the sealing member placed inside with a simple structure using the boss part of the mating surface.
Also, the cooling structure is simple, the processing etc. applied to the housing during manufacturing to obtain the structure is easy, and the cooling water can be appropriately distributed and is not interposed between the mating surfaces of the housing. It is an object of the present invention to provide a casing for a rotary piston engine that can improve the durability of a sealing member.

[Means to solve the problem]

The present invention is applied to a casing of a rotary piston engine, which includes a rotor housing having a trochoidal inner circumferential surface and a side housing fastened to both sides of the rotor housing using tension bolts.

The feature is that the inner wall and outer wall of the casing are integrated through a boss through which the tension bolt is inserted, and the output is surrounded by both walls and the boss. A cooling water passage through which cooling water flows in the axial direction is formed.
Seal grooves into which the seal member is fitted are formed on the inside and outside of the cooling water passage on one surface of the mating surfaces of both housings, and at least the hot zone of the casing is formed between the inner seal groove and the bolt insertion hole. A communication groove is formed on the housing-side mating surface of the boss portion between the cooling water passages, which communicates the adjacent cooling water passages.

[Effect of idea]

According to the present invention, the communication groove that communicates the cooling water passage is formed on the housing-side mating surface of the boss portion between the inner seal groove and the bolt insertion hole in the hot zone. Seal members in areas that are difficult to reach,
It can be cooled by cooling water in the communication groove.
Therefore, the sealing member interposed on the mating surface of the housing is prevented from being locally exposed to high heat, and the durability of the sealing member is also improved. Further, by adopting a simple cooling structure using the boss portion of the mating surface in which the seal groove is formed, the effort required in casting the housing and subsequent machining when forming the communication groove in the housing is reduced.

〔Example〕

The present invention will be described in detail below based on examples thereof.

FIG. 1 is an end view of a rotor housing to which the casing of the rotary piston engine of the present invention is applied. The casing 1 is fastened to a rotor housing 3 having a trochoidal inner peripheral surface 2 using tension bolts 4 on both sides thereof. It consists of a side housing 5 shown in FIG.

In such a casing 1, the inner wall portion 6 and outer wall portion 7 of the rotor housing 3 and the side housing 5 are integrated via a boss portion 8 through which the tension bolt 4 is inserted. Surrounded by both walls 6, 7 and boss 8, a large number of cooling water passages 10 are formed through which cooling water flows in the direction in which the output shaft 9 extends.

This cooling water passage 10 is provided in a hot zone H from a position 12 where a spark plug is attached to a position where an exhaust port 13 is opened along the direction of an arrow 11 in which a rotor (not shown) rotates, and also in a hot zone H from a position 12 where a spark plug is attached to a position where an exhaust port 13 is opened. 14 is also provided in the cold zone C on the open side.

In these cooling water passages 10, the cooling water passage 10h in the hot zone that requires a strong cooling effect is
Cooling water passage 10 of cold zone C as required
By circulating cooling water of different temperatures, desired cooling can be achieved.

A seal member 15 is interposed between the mating surfaces of the rotor housing 3 and the side housing 5 so that the cooling water passage 10 flows between the rotor housing 3 and the side housing 5 without leaking. In this example, seal grooves 16 and 17 for fitting the seal member 15 into the inner and outer sides of the cooling water passage 10, that is, the inner wall portion 6 and the outer wall portion 7, on the mating surface 3a of the rotor housing 3 among the mating surfaces. is formed.

At least in the hot zone H of the casing 1, an adjacent cooling water passage is provided on the mating surface on the housing side of the boss portion 8 between the inner seal groove 16 and the bolt insertion hole 18 through which the tension bolt 4 is inserted. Communication groove 1 that communicates 10, 10
9 is formed.

As shown in FIG. 3, this communication groove is provided to an extent necessary for cooling the sealing member 15, and usually has the same depth as the sealing grooves 16 and 17 (see FIG. 2). Note that since the outer wall portion 7 on the mating surface 3a is cooled to some extent by the outside air, unlike the inner wall portion side exposed to combustion gas, the outer seal groove 17
No communication groove is provided between the bolt insertion hole 18 and the bolt insertion hole 18. However, if an exhaust manifold is installed near the exhaust port 13 and heat dissipation in that area is insufficient, the communication groove 1 as shown in the figure
If 8A is provided, cooling can be accelerated. Furthermore, if cooling of the seal member 15 is required in the cold zone C as well, a communication groove similar to that described above may be formed, although not shown.

According to such an example, the seal member 15 is cooled almost uniformly all around the circumference in the following manner, and its deterioration and burnout can be reduced.

The cooling water flowing through the cooling water passage 10 in the hot zone H cools the inner wall 6 and outer wall 7 near the cooling water passage. On the other hand, since the tension bolt 4 for fastening both the housings 3 and 5 is inserted through the boss part 8 located between the cooling water passages, there is no room for the cooling water to flow through the boss part 8, and the inner wall part 6 is filled with combustion gas. heat acts strongly.

However, as described above, the inner seal groove 16 and the bolt insertion hole 1 through which the tension bolt 4 is inserted.
A communication groove 19 that communicates the adjacent cooling water passages 10, 10 is formed in the mating surface of the housing side of the boss portion 8 between the cooling water passages 10 and 8, so that a portion of the circulating cooling water flows therethrough. As a result, the communication groove 1
Exposure of the sealing member 15 in the portion corresponding to 9 to high heat is reduced, and local deterioration thereof is suppressed.

As can be seen from the above description, the inner wall and outer wall of the casing are integrated through the boss, and a cooling water passage through which cooling water flows is formed. A seal groove into which the seal member is fitted is formed on the outside, and a communication groove for communicating the cooling water passage is formed on the mating surface on the housing side of the boss portion between the inside seal groove and the bolt insertion hole in the hot zone. Therefore, it is possible to cool the seal member at a location where cooling from the cooling water passage is difficult to reach with the cooling water in the communication groove. Therefore, the sealing member interposed on the mating surface of the housing is prevented from being locally exposed to high heat, and the durability of the sealing member is improved. In addition, with a simple cooling structure that uses the boss part of the mating surface where the seal groove is formed, the seal member placed inside can be cooled. Machining etc. become easier, and costs in manufacturing the housing can also be reduced.

[Brief explanation of the drawing]

Fig. 1 is an end view of a rotor housing to which the casing of the rotary piston engine of the present invention is applied, Fig. 2 is a longitudinal cross-sectional view of the rotary piston engine, and Fig. 3 is a horizontal cross-section of the - line in Fig. 1. This is an enlarged view. 1... Casing, 2... Trochoid inner peripheral surface,
3...Rotor housing, 3a...Mating surface, 4...
...Tension bolt, 5...Side housing,
6...Inner wall part, 7...Outer wall part, 8...Boss part, 9
...Output shaft, 10,10h...Cooling water passage, 15
... Seal member, 16, 17 ... Seal groove, 18
...Bolt insertion hole, 19...Communication groove, H...Hot zone.

Claims (1)

[Scope of Claim for Utility Model Registration] In a rotary piston engine casing consisting of a rotor housing having a trochoidal inner circumferential surface and a side housing fastened to both sides of the rotor housing using tension bolts, an inner wall portion and an outer wall portion of the casing are integrated through a boss portion through which the tension bolt is inserted, and a cooling water passage is formed so as to be surrounded by both walls and the boss portion, through which cooling water flows in the direction of the output shaft. Seal grooves into which the seal member is fitted are formed on the inside and outside of the cooling water passage on one surface of the mating surfaces of both housings, and at least in the hot zone of the casing, between the inner seal groove and the bolt insertion hole. A casing for a rotary piston engine, characterized in that a communication groove for communicating adjacent cooling water passages is formed on a mating surface of the boss portion on the housing side.