JPH06592Y2 - Rotor housing for rotary piston engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a rotor housing of a rotary piston engine, and more particularly to the shape of a rotor sliding surface thereof.

(Prior Art) Generally, there is known a rotary piston engine in which a rotor makes a planetary rotational movement in a casing formed by a rotor housing and a side housing.

The rotor housing of such a rotary piston engine, as described in, for example, Japanese Utility Model Application Laid-Open No. 60-4722, has its inner peripheral surface slidable by an apex seal arranged at the apex of the rotor. In order to reduce the wear of the seal, it is composed of a curve which is translated outward by a certain amount with respect to the geometrically determined peritrochoid curve.

(Problems to be solved by the invention) By the way, a rotor in which an apex seal slides on the inner peripheral surface of such a rotor housing stops at a position before the compression stroke where the rotational resistance of the rotor increases when the engine stops. (Refer to the positional relationship between the rotor housing and the rotor in FIG. 1), the carbon adhering to one downward surface of the rotor is separated from the rotor by the action of gravity or the like in the exhaust state of the rotor housing in the stopped state. It falls on the corresponding inner surface.

Therefore, at the first rotation when cranking is started, the apex seal b located at the apex of the rotor a scrapes up the rotor housing that has fallen onto the inner peripheral surface of the rotor housing c, as shown in FIG. That is,
The scraped carbon d is generated at a portion where the rotor a approaches the rotor housing c and the gap between them becomes small.
Are leveled and deposited in the gap between the rotor and the rotor housing at that portion.

Therefore, there is a problem in that the deposited carbon becomes a large resistance when the rotor a starts to rotate due to the start of cranking, which hinders the smooth planetary rotational movement of the rotor a.

The present invention has been made in view of the above points, and an object thereof is to provide a rotor housing of a rotary piston engine in which the rotational resistance of the rotor at the start of cranking is reduced.

(Means for Solving the Problems) In order to achieve the above object, the present invention relates to a rotary piston engine in which a trocolloid reference surface as a rotor sliding surface on which a rotor slides is formed on the inner circumference. In the rotor housing, the rotor sliding surface from the exhaust port opening portion of the rotor housing to the minor shaft portion on the leading side (advancing side of rotor rotation) is deviated outward from the reference surface.

(Function) Even if carbon that has fallen onto the inner peripheral surface of the rotor housing from one surface of the rotor or in the vicinity of the side seals of the rotor is picked up during the first rotation at the start of cranking, the exhaust port of the rotor housing Since the rotor sliding surface is deviated outward from the reference surface from the opening to the minor axis portion on the leading side, the scraped carbon is accumulated in the gap between the rotor and the rotor housing and It does not cause a large rotation resistance.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a rotor housing of a rotary piston engine, and an inner peripheral surface 1a thereof is a sliding surface on which an apex seal 3 arranged on the top of a rotor 2 slides.

The inner peripheral surface 1a of the rotor housing 1 of the rotary piston engine basically coincides with the reference surface 4 which is formed by a curve parallel to the peritrochoid curve by an outward translation. In a predetermined section from the opening of the exhaust port 5 to the minor shaft portion 6 on the leading side thereof,
It is deviated to the outer side from the reference plane 4, and the gap 7 formed between the rotor 2 and the surface 2a is slightly widened (see FIG. 2).

Deviating from the reference surface 4 beyond this range is not desirable because it causes deterioration of the sealing property of the apex seal 3. That is, if the displacement is made beyond the short axis portion 6, a dilution from the exhaust side to the intake side is caused, and if the displacement is made beyond the opening of the exhaust port 5, the leakage of combustion gas is also caused. This is because the problem of

The range of deviation is the apex seal 3 of the rotor 2.
Front side positions P ₁ , P ₂ , P ₃ (See Fig. 3, L ₁ = L ₂ = 10 mm)
As for the change in the gap ΔF between the rotor 2 and the rotor housing 1, as shown in FIG. 4, the apex seal 3 on the side of the minor shaft 6 at the compression top dead center of the rotor 2 is eccentric. The rotation angle of the shaft 8 is -11
It is desirable to set it in the range of 0 ° to −30 °. The rotation angle of the eccentric shaft 8 is 0 ° at the position of the short shaft portion 6 and −130 ° at the opening end of the exhaust port 5.

The amount of deviation may be such that carbon deposited in the gap 7 between the rotor housing 1 and the rotor 2 at the start of cranking does not give a large resistance when the rotor 2 rotates, and It may be about 0.1 to 0.2 mm. In the above embodiment, 9 is a corner seal, 10 is a side seal, 11 is an intake port, 1
2 and 13 are spark plugs.

According to the above structure, the inner peripheral surface 1a of the rotor housing 1 is displaced outward at the portion where the rotational resistance of the rotor 2 increases due to carbon deposition, so that the rotor 2 at the start of clan In the first rotation, the rotational resistance of the rotor 2 due to carbon deposition does not increase so much, the rotor 2 easily rotates, and the startability of the engine increases.

(Effect of the Invention) As described above, according to the present invention, the inner peripheral surface of the rotor housing is displaced outward at the portion where carbon is deposited during the first rotation at the start of cranking, so that the engine starting resistance is Can be reduced.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a general configuration diagram of a rotary piston engine, FIG. 2 is a configuration diagram of a main part of the same, FIG. 3 is an explanatory diagram of a gap between a rotor housing and a rotor, FIG. 4 is a diagram showing test results, and FIG. 5 is a diagram similar to FIG. 2 showing a conventional example. 1 ... Rotor housing, 1a ... Inner peripheral surface, 2 ... Rotor, 3 ... Apex seal, 4 ... Reference surface, 5 ... Exhaust port, 6 ... Short shaft portion, 7 ... Gap.

Claims (1)

[Scope of utility model registration request] 1. In a rotor housing of a rotary piston engine in which a trochoidal reference surface as a rotor sliding surface on which a rotor slides is formed on an inner circumference, a short side from an exhaust port opening portion of the rotor housing to a leading side thereof. A rotor housing for a rotary piston engine, wherein a rotor sliding surface extending over the shaft portion is deviated outward from the reference surface.