CN-116804398-B - Internal combustion engine

CN116804398BCN 116804398 BCN116804398 BCN 116804398BCN-116804398-B

Abstract

The internal combustion engine includes a cylinder in which a piston reciprocates, a stepped portion formed on an upper end portion of an inner peripheral surface of the cylinder, and a ring member provided to the stepped portion, having a cylindrical shape. The thickness of the ring member decreases toward the bottom distal center of the piston, and the outer peripheral surface of the ring member is an inclined surface, wherein the lower end of the outer peripheral surface is positioned closer to the center of the ring member in the radial direction than the upper end of the outer peripheral surface.

Inventors

Kohyoyama Takumi
YAMAMOTO KAZUNARI
Hou Tengcao

Assignees

五十铃自动车株式会社

Dates

Publication Date: 20260508
Application Date: 20230317
Priority Date: 20220324

Claims (9)

1. An internal combustion engine, comprising: A cylinder in which a piston reciprocates; A step portion formed at an upper end portion of an inner peripheral surface of the cylinder, and A ring member provided at the step portion, having a cylindrical shape, wherein, The thickness of the ring member decreases toward the bottom dead center of the piston, and The outer peripheral surface of the ring member is an inclined surface, wherein a lower end of the outer peripheral surface is positioned closer to a center of the ring member in a radial direction than an upper end of the outer peripheral surface, The internal combustion engine further includes an injector that injects fuel, wherein, In the ring member, a plurality of injection target portions as portions to be injected with fuel in the injector have a thickness smaller than that of other portions, and The injection target portions are formed at predetermined intervals in a circumferential direction of the ring member.
2. The internal combustion engine according to claim 1, wherein, An inner peripheral surface of the step portion is an inclined surface parallel to the outer peripheral surface, which is an inclined surface of the ring member.
3. The internal combustion engine according to claim 1, wherein, The thickness of the lower end of the ring member is equal to or less than half the thickness of the upper end of the ring member.
4. The internal combustion engine according to claim 1, wherein, The inner peripheral surface of the ring member is a mirror surface.
5. The internal combustion engine according to claim 1, wherein, The ejection target portion is a portion on the outer peripheral surface of the ring member where a concave portion is formed.
6. The internal combustion engine according to claim 5, wherein, A plurality of convex portions are formed on the inner peripheral surface of the cylinder, the convex portions being engaged with the respective concave portions of each of the injection target portions.
7. The internal combustion engine according to claim 6, wherein, The concave portion is a curved groove, and The convex portion has a curved convex shape.
8. The internal combustion engine according to claim 5, wherein, The minimum thickness in the recessed portion is less than half the thickness of the other portions of the ring member.
9. The internal combustion engine according to claim 1, wherein, The ejection target portion is a portion on the inner peripheral surface of the ring member where a concave portion is formed.

Description

Internal combustion engine Technical Field The present disclosure relates to an internal combustion engine including a cylinder and a piston. Background In an internal combustion engine, a ring member is provided at a stepped portion formed on an upper portion of an inner peripheral surface of a cylinder. For example, japanese unexamined patent application publication No. 2017-089410 discloses an internal combustion engine in which a scraper ring is provided to a stepped portion to remove soot adhering to a piston. Prior Art Patent literature Patent document 1 Japanese unexamined patent application publication No. 2017-089410 Disclosure of Invention Problems to be solved by the invention In internal combustion engines, it is desirable to reduce heat loss. However, when the ring member is provided at the upper portion of the cylinder, it is difficult to maintain the inside of the combustion chamber at a high temperature due to heat loss caused by the ring member. The present disclosure has been made in view of these points, and an object thereof is to provide an internal combustion engine capable of reducing heat loss even in the case where a ring member is provided. Means for solving the problem In one aspect of the present disclosure, there is provided an internal combustion engine including a cylinder in which a piston reciprocates, a step portion formed at an upper end portion of an inner peripheral surface of the cylinder, and a ring member provided to the step portion, having a cylindrical shape, wherein a thickness of the ring member decreases toward a bottom dead center of the piston, and an outer peripheral surface of the ring member is an inclined surface, wherein a lower end of the outer peripheral surface is closer to a center of the ring member in a radial direction than an upper end of the outer peripheral surface. Further, the inner peripheral surface of the step portion may be an inclined surface parallel to an outer peripheral surface, which is an inclined surface of the ring member. Further, the thickness of the lower end of the ring member may be equal to or less than half the thickness of the upper end of the ring member. Further, the inner peripheral surface of the ring member may be a mirror surface. Further, the internal combustion engine may further include an injector that injects fuel, wherein in the ring member, a thickness of a plurality of injection target portions that are portions of the fuel to be injected in the injector may be smaller than a thickness of other portions. Further, the ejection target portion may be a portion on the outer peripheral surface of the ring member where a concave portion is formed. Further, a plurality of convex portions may be formed on the inner peripheral surface of the cylinder, the convex portions being fitted with corresponding concave portions of each injection target portion. Further, the concave portion may be a curved groove, and the convex portion may have a curved convex shape. Further, the minimum thickness in the recessed portion may be less than half the thickness of the other portion of the ring member. Further, the ejection target portion may be a portion on the inner peripheral surface of the ring member where the concave portion is formed. Effects of the invention According to the present disclosure, even if the ring member is provided, heat loss in the internal combustion engine can be reduced. Drawings Fig. 1 is a schematic diagram showing an internal configuration of an internal combustion engine 1 according to an embodiment. Fig. 2 is a schematic diagram showing the internal combustion engine 100 according to the comparative example. Fig. 3 is a schematic diagram showing a modified example of the internal combustion engine 1. Detailed Description < Arrangement of International internal Combustion Engine > A configuration of an internal combustion engine according to an embodiment will be described with reference to fig. 1. Fig. 1 is a schematic diagram showing an internal configuration of an internal combustion engine 1 according to an embodiment. In fig. 1, only a part of the internal combustion engine 1 is shown, and other components are omitted for convenience of explanation. The internal combustion engine 1 is, for example, an engine mounted on a vehicle. As shown in fig. 1, the internal combustion engine 1 includes a cylinder 10, a piston 15, a stepped portion 20, a cylinder head 25, a gasket 30, and a ring member 40. The cylinder 10 is made of metal and formed in a cylindrical shape. A piston 15 is accommodated in the cylinder 10. The piston 15 reciprocates between a top dead center and a bottom dead center in the cylinder 10. In fig. 1, the piston 15 is located at the top dead center. The piston ring 16 is fitted into a groove formed on the outer circumferential surface of the piston 15. As shown in fig. 1, the stepped portion 20 is located at an upper end portion of the inner peripheral surface 11 of the cylinder 10. W