JPH0318667Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is applicable to rotary piston engines, especially two
The present invention relates to a housing fixing device for a multi-cylinder rotary piston engine having more than one cylinder.

(Prior Art) Generally, in a multi-cylinder rotary piston engine, the engine body is provided with a plurality of rotor housings corresponding to the number of cylinders, two front and rear end side housings, and interposed between adjacent rotor housings. These housings are fastened together with a plurality of tension bolts (Japanese Patent Application Laid-Open No. 1989-1999).
-Refer to Publication No. 69208, etc.). Note that tension bolts having different lengths may be used. This means that when each housing of the engine body is fastened with multiple tension bolts of the same length (approximately the longitudinal length of the engine body), even when disassembling only the portion corresponding to one cylinder, This is because all tension bolts would have to be removed and the entire engine body would have to be disassembled.

(Problem that the invention aims to solve) By the way, in such a rotary piston engine, the tension bolt undergoes thermal expansion during operation, and its tightening force decreases. Hot zone side (side corresponding to the explosion, expansion, and exhaust strokes of the combustion cycle)
The tension bolt used in the engine body is different from the tension bolt used in the cold zone side of the engine body (the side corresponding to the intake and compression strokes of the combustion cycle), and as a result, each housing of the engine body is uneven. Even with a certain amount of tightening force, the bolts were tightened tightly, and there was a risk of gas leaks, cooling water leaks, etc.

The present invention has been made in view of these points, and its purpose is particularly for tension bolts of different lengths used for convenience in disassembling the engine body as described above. , we focused on the fact that the thermal expansion differs depending on the length when the temperature change is the same, and by appropriately setting the placement of tension bolts of different lengths, it was possible to cause the tension bolts to undergo thermal expansion. Even when the tightening force is reduced, each housing of the engine body is maintained in a state of being fastened with a uniform tightening force regardless of whether it is in a hot zone or a cold zone.

(Means for solving the problem) In order to achieve the above object, the solution of the present invention is such that the engine body is composed of a rotor housing and a side housing, and these housings are fastened together by a plurality of tension bolts. In the conventional rotary piston engine, tension bolts of different lengths are used. The hot zone side of the engine body is fastened with a short tension bolt, and the cold zone side is fastened with a long tension bolt.

(Function) With the above configuration, in the present invention, when the tension bolt undergoes thermal expansion during engine operation, the tension bolt on the hot zone side of the engine body is heated to a higher temperature than the tension bolt on the cold zone side. On the other hand, its length is shorter than the length of the tension bolt on the cold zone side, so in the end, the thermal expansion of the tension bolt on the hot zone side is almost equal to the thermal expansion of the tension bolt on the cold zone side. As a result, each housing of the engine main body is always maintained in a state where a uniform tightening force is applied regardless of a decrease in the tightening force due to thermal expansion of the tension bolt.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 and FIG. 2 show an example in which the present invention is applied to a three-cylinder rotary piston engine, and 1 is an engine body, and the engine body 1 has a trochoid-shaped inner circumferential surface. It has three rotor housings 2, 3, 4, two end side housings 5, 6, and two intermediate side housings 7, 8, and the rotor housing 2 has an end side housing 5, an intermediate side housing 7, and The rotor housing 3 is kept airtight by the intermediate side housings 7 and 8 to form the working chamber 9 of the first cylinder, and the rotor housing 3 is kept airtight by the intermediate side housings 7 and 8 to form the working chamber 10 of the second cylinder. is maintained airtight by the intermediate side housing 8 and the end side housing 6 to form the working chamber 11 of the third cylinder.

Reference numeral 12 denotes an eccentric shaft penetrating the axial center of the engine body 1 and extending in the front-rear direction, and 13 a rotor that is supported by the eccentric shaft 12 and rotates planetarily in each of the working chambers 9 to 11 of the engine body 1. The rotation of the rotor 13 causes the inside of each working chamber 9 to 11 to be
Inhalation as a combustion cycle while being divided into two chambers,
The compression, explosion, expansion, and ejection steps are performed in sequence. In FIG. 2, 14 is an intake port, and 15 is an exhaust port. This exhaust port 1
5 and the eccentric shaft 12 (explosion of the combustion cycle,
The part of the engine body 1 located above the straight line 1 (corresponding to the combustion cycle (corresponding to each suction and compression stroke)
is called the cold zone because it is not affected by the heat of combustion.

Each housing 2 of the engine main body 1
- 8 are fastened using a plurality of three types of tension bolts 16, 17, and 18 of different lengths, each for the hot zone side and the cold zone side of the engine body 1. That is, the engine body 1
On the hot zone side of the engine, two types of short tension bolts 16 and 17 are used in parallel around the periphery of the engine body.
6 passes through the end side housing 5, the rotor housing 2, the intermediate side housing 7, and the rotor housing 3 in sequence from the side of the end side housing 5, and is screwed into the intermediate side housing 8;
Further, the tension bolt 17 passes through the end side housing 6 and the rotor housing 4 from the side of the end side housing 6 and is screwed into the intermediate side housing 8 . On the other hand, engine body 1
On the cold zone side of the engine, a plurality of long tension bolts 18 are lined up around the periphery of the engine body 1, and these tension bolts 18 are
It passes through the end side housing 5, the rotor housing 2, the intermediate side housing 7, the rotor housing 3, the intermediate side housing 8, and the rotor housing 4 in order from the side of the end side housing 5, and is screwed into the end side housing 6. ing.

In addition, 19 to 28 are cooling water passages, and 29 is an eccentric shaft 1.
A flywheel 30 attached to one end of the engine main body 1 is a pin for positioning when the adjacent housings 2 to 8 of the engine body 1 are fastened together.

Therefore, in the above embodiment, the shorter tension bolts 16 and 17 are used on the hot zone side of the engine body 1, and the longer tension bolt 18 is used on the cold zone side, so that the engine Tension bolt 16 during operation
18 undergo thermal expansion, the tension bolts 16 and 17 on the hot zone side will be heated to a higher temperature than the tension bolt 18 on the cold zone side, but their length will be shorter than that of the tension bolt 18 on the cold zone side. Since it is shorter than the length of 18, the result is the thermal expansion of the tension bolts 16 and 17 on the hot zone side and the tension bolt 18 on the cold zone side.
is equal to the thermal expansion of As a result, each of the housings 2 to 8 of the engine body 1 is always maintained in a state of being fastened with a uniform tightening force despite the reduction in tightening force due to thermal expansion of the tension bolts 16 to 18, preventing gas leakage and cooling. Occurrence of water leakage etc. can be prevented. In the above case, all the short tension bolts were used on the hot zone side and all the long tension bolts were used on the cold zone side, but many of the short tension bolts were used on the hot zone side, and Simply by using more long tension bolts on the cold zone side, the difference in thermal expansion between the hot zone side and the cold zone side can be alleviated.

Furthermore, even if the tension bolts 16 to 18 of different lengths are used separately for the hot zone side and the cold zone side of the engine body 1 as described above, only the portion of the engine body 1 corresponding to one cylinder can be disassembled. Of course, the effect of facilitating the work during inspection can be obtained. For example, when disassembling and inspecting the working chamber 11 of the third cylinder, it is necessary to completely remove the tension bolt 17, but the tension bolt 16 may remain fastened, and the tension bolt 18 is attached to the end side housing 6. Since it is sufficient to release the screwed state, the disassembly work becomes easy. Furthermore, since parts corresponding to other cylinders are not disassembled, assembly work after inspection can be easily performed.

In the above embodiment, the present invention was applied to a three-cylinder rotary piston engine, but it goes without saying that it can be similarly applied to a two-cylinder, four or more cylinder rotary piston engine.

(Effects of the invention) As described above, according to the rotary piston engine housing fixing device of the invention, a short tension bolt is used on the hot zone side of the engine body, and a long tension bolt is used on the cold zone side. By using bolts, the thermal expansion of the tension bolt on the hot zone side and the tension bolt on the cold zone side is almost equal, so even though the tightening force decreases due to thermal expansion, the tightening force is always uniform. Therefore, each housing of the engine body can be maintained in a tightened state, and gas leakage, cooling water leakage, etc. can be prevented from occurring.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional side view showing the overall configuration of a three-cylinder rotary piston engine, and FIG. 2 is a sectional view taken along the - line in FIG. 1. 1... Engine body, 2, 3, 4... Rotor housing, 5, 6... End side housing,
7, 9... Intermediate side housing, 16-18...
...Tension bolt.

Claims (1)

[Scope of utility model registration request] In a rotary piston engine in which the engine body is composed of a rotor housing and a side housing, and these housings are fastened together by a plurality of tension bolts, the tension bolts have different lengths and are attached to the hot zone side of the engine body. A housing fixing device for a rotary piston engine, characterized in that the is fastened with a short tension bolt, and the cold zone side is fastened with a long tension bolt.