JPS6313396Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a rotor for a rotary piston engine, and more particularly to a rotor structure for preventing the occurrence of knocking.

(Prior Art) Generally, in a rotary piston engine, a hollow cooling chamber is formed inside a rotor that rotates planetarily within a casing, and cooling oil is introduced into the cooling chamber to cool the rotor. This is intended to improve the durability of the engine by preventing thermal deterioration of gas seal members, oil seal members, etc. installed in the engine.

However, such a rotary piston engine has a problem in that knocking occurs when the engine is operated under high load. Therefore, as shown in Japanese Unexamined Patent Publication No. 54-124105, the present applicant has proposed that the heat of the leading side portion of the succeeding rotor flank surface is applied to the trailing side portion of the preceding rotor flank surface. Knocking is prevented by focusing on the fact that the trailing side portion of the rotor flank surface becomes a knotting zone, which occurs when heat conducts beyond the temperature range and the temperature rises on the trailing side portion of the rotor flank surface. We are proposing countermeasures.

However, when the present applicant subsequently conducted detailed experimental research on the phenomenon of knocking, it was found that in the combustion chamber, the fire propagated smoothly toward the leading side as the rotor rotated, and the leading side portion of the rotor flank surface Although the temperature is high, the combustion does not flow smoothly to the trailing side and is difficult to burn, and the trailing side portion of the rotor flank is at a relatively low temperature and cannot be called a knocking zone. Rather, it was found that the trailing side edge of the rotary recess, which serves as the combustion chamber, is a heat point, and knocking is more likely to occur due to abnormal ignition at this heat point.

(Purpose of the invention) The purpose of the invention is to effectively cool down the heat point where knocking occurs, that is, near the trailing side edge of the rotary recess, by using the cooling effect of the cooling oil in the cooling chamber. By doing so, the purpose is to effectively and reliably prevent the occurrence of knocking even with a simple structure.

(Structure of the invention) In order to achieve the above object, the technical solution of the invention is to cool the rotor by introducing cooling oil into the cooling chamber formed inside the rotor as described above, and to form a recess in the flank surface of the rotor. In the rotary piston engine thus formed, by forming the wall portion near the trailing side edge of the recess among the wall portions constituting the cooling chamber with a material having higher thermal conductivity than the rotor base material, the rotary recess tray The cooling effect of the cooling oil in the cooling chamber on the vicinity of the ring side edge is promoted to sufficiently cool the trailing side edge of the rotary recess and prevent it from becoming a heat point.

(Effect of the invention) Therefore, according to the invention, the trailing side edge of the recess in the rotor of a rotary piston engine is prevented from becoming a heat point by the sufficient cooling action of the cooling oil in the cooling chamber. Therefore, even with a simple configuration, it is possible to effectively and reliably prevent the occurrence of knocking, and thus it is extremely effective in preventing knocking in rotary piston engines, and can be easily implemented. be.

(Example) Hereinafter, an example as a specific example of the technical means of the present invention will be described based on the drawings.

1 and 2 schematically show the structure of a rotary piston engine, in which 1 indicates a multi-arc inner circumferential surface 2.
A casing constituted by a rotor housing 2 having a rotor housing 2 and side housings 3, 3 disposed on both sides of the rotor housing 2;
As the rotor 4 rotates, the inside of the casing 1 is divided into three working chambers 6, and each stroke of intake, compression, explosion, expansion, and exhaust is carried out. It is designed to be carried out sequentially. 7 is an intake port provided in the side housing 3, 8 is an exhaust port provided in the rotor housing 2, and 9 and 10 are leading side and trailing side spark plugs, respectively.

The rotor 4 is made of cast iron, for example.
As shown in FIG. 3, a recess 11 constituting a combustion chamber is formed in each flank surface 4a. Also, inside the rotor 4, as shown in FIG.
A plurality of hollow cooling chambers 15, 15, .
is formed. On the other hand, an oil supply passage 16 extending in the axial direction is formed in the center of the eccentric shaft 5, and an oil jet whose one end communicates with the oil supply passage 16 and whose other end opens toward the cooling chamber 15 is formed. A hole 17 is formed so that oil from the oil supply passage 16 is jetted out from the oil jet hole 17 and guided to the cooling chamber 15 as cooling oil to cool the rotor 4 . In FIG. 2, reference numeral 18 indicates an oil passage for supplying oil from the oil supply passage 16 to the supporting portion of the rotor 4, 19 indicates an internal gear provided on the rotor 4, and 20 indicates an internal gear.
is an external gear that is provided on the eccentric shaft 5 and meshes with the internal gear.

As shown in FIG. 4, the cooling chamber 15
Of the wall parts (outer wall part 13) constituting the recess 1
The wall portion 13a near the trailing side (rotation rear) edge of the rotor 4 is formed by integrally casting a material (for example, copper) with higher thermal conductivity than the rotor base material (cast iron). The trailing side edge of the recess 11 is cooled by cooling oil in the cooling chamber 15 with good heat conduction.

Further, the wall thickness t 1 of the portion 13b on the trailing side of the recess 11 of the outer wall portion 13 is equal to the thickness _{t 2 of} the portion 13c on the leading side of the recess 11.
(t ₁ > t ₂ ), and the trailing side portion of the flank surface 4a of the rotor 4 is cooled by the cooling oil in the cooling chamber 15 more than the leading side portion of the flank surface 4a. It's making it difficult.

Therefore, in the above embodiment, the rotor 4
is cooled by introducing cooling oil into a cooling chamber 15 formed therein. In that case, of the wall portion (outer wall portion 13) constituting the cooling chamber 15, the wall portion 13a near the trailing side edge of the recess 11 is made of a material having higher thermal conductivity than the rotor base material (e.g. cast iron) (e.g. By forming the recess 11 with copper), the recess 11
The wall 13a near the trailing side edge of the recess 11 is cooled by the cooling oil in the cooling chamber 15 with better heat conduction than other parts, and the trailing side edge of the recess 11 becomes a heat point. Therefore, the occurrence of knocking can be effectively prevented.

Further, by making the wall thickness of the trailing side portion 13b of the outer wall portion 13 thicker than the leading side portion 13c than the recess 11, the trailing side portion of the flank surface 4a of the rotor 4 is formed on the leading side of the flank surface 4a. Cooling chamber 1 than part
It becomes difficult to be cooled by the cooling oil in step 5. As a result, it is possible to suppress overcooling of the trailing side portion of the flank surface 49, which is in a relatively low temperature state and corresponds to the trailing side where fire propagation does not occur smoothly in the combustion chamber and combustion is difficult. Combustibility and emission performance can be improved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a longitudinal side view showing the schematic structure of a rotary piston engine, FIG. 2 is a longitudinal front view thereof, FIG. 3 is a plan view showing the flank surface of the rotor, and FIG. The figure is an enlarged cross-sectional view of main parts showing the internal structure of the rotor. 1...Casing, 2...Rotor housing,
3...Side housing, 4...Rotor, 4a...
... flank surface, 11 ... recess, 12 ... inner wall, 13 ... outer wall, 13a ... wall near the trailing side edge of recess, 15 ... cooling chamber.

Claims (1)

[Scope of utility model registration request] In a rotary piston engine that cools the rotor by guiding cooling oil into a cooling chamber formed inside the rotor, and in which a recess is formed in the flank surface of the rotor, the trailing side edge of the recess among the walls forming the cooling chamber. A rotor for a rotary piston engine, characterized in that a nearby wall is formed of a material with higher thermal conductivity than the rotor base material.