JP6397708B2 - engine - Google Patents

Description

  The present invention relates to an engine, and more particularly to an engine capable of increasing the cooling efficiency of a piston head.

  Conventionally, as an engine, a pressure ring is fitted into the ring groove of the piston head, and the pressure ring is composed of a top dead center side ring and a bottom dead center side ring, and the top dead center side ring and the bottom dead center side. There is a configuration in which the mutual contact surfaces of the rings are inclined with respect to a direction parallel to the cylinder axis (see, for example, Patent Document 1).

  According to this type of engine, there is an advantage that the pressure ring is pressed against the cylinder wall by the gas pressure generated in the combustion chamber, and the sealing performance of the pressure ring can be improved.

  However, in this Patent Document 1, the mutual contact surfaces of the top dead center side ring and the bottom dead center side ring are inclined so as to approach the top dead center side as they approach the cylinder wall. There is a problem because the outer peripheral surface of the ring is in contact with the cylinder wall and the outer peripheral surface of the top dead center side ring is separated from the cylinder wall.

Japanese Utility Model Publication No. 43-23202 (see FIGS. 2 and 3)

<Problem> The cooling efficiency of the piston head is low.
In this patent document 1, since the outer peripheral surface of the bottom dead center side ring is in contact with the cylinder wall and the outer peripheral surface of the top dead center side ring is separated from the cylinder wall, the piston top surface is heated by the piston head. It is conducted to the cylinder wall through the bottom dead center ring far from the piston, and the cooling efficiency of the piston head is low.

  The subject of this invention is providing the engine which can improve the cooling efficiency of a piston head.

  As a result of research, the inventors of the present invention have focused on the fact that the cooling efficiency of the piston head increases when the outer peripheral surface of the top dead center side ring is in contact with the cylinder wall, and have reached the present invention.

Invention specific matters of the invention according to claim 1 are as follows.
As illustrated in FIG. 1B, the pressure ring (3) is fitted in the ring groove (2) of the piston head (1), and the pressure ring (3) is overlapped with each other on the top dead center side ring ( 4) and a bottom dead center ring (5), and the mutual contact surfaces (4a) and (5a) of the top dead center ring (4) and the bottom dead center ring (5) are the cylinder center axis (6). In an engine configured to be inclined with respect to a direction parallel to
As illustrated in FIG. 1B, as the mutual contact surfaces (4a) and (5a) of the top dead center side ring (4) and the bottom dead center side ring (5) approach the cylinder wall (7), Inclined to approach the bottom dead center, the outer peripheral surface (4b) of the top dead center ring (4) is in contact with the cylinder wall (7),
As illustrated in FIG. 1B, a bottom dead center side extension surface ( 4) extending from the contact surface (4a) toward the cylinder wall (7) toward the bottom dead center side of the top dead center side ring (4) ( 4e), and an acute edge portion (4d) toward the bottom dead center side is formed at the corner of the outer peripheral surface (4b) and the bottom dead center side extension surface (4e) of the top dead center side ring (4). An engine characterized by that.

(Invention of Claim 1)
The invention according to claim 1 has the following effects.
<Effect> The cooling efficiency of the piston head can be increased.
As illustrated in FIG. 1B, since the outer peripheral surface (4b) of the top dead center side ring (4) is in contact with the cylinder wall (7), the heat of the piston head (1) is high. It is conducted to the cylinder wall (7) through the top dead center side ring (4) close to (1a), and the cooling efficiency of the piston head (1) can be enhanced.

<Effect> The sealing performance of the pressure ring can be improved.
As illustrated in FIG. 1B, as the mutual contact surfaces (4a) and (5a) of the top dead center side ring (4) and the bottom dead center side ring (5) approach the cylinder wall (7), Since it is inclined to approach the bottom dead center side and the outer peripheral surface (4b) of the top dead center side ring (4) is in contact with the cylinder wall (7), the bottom dead center is generated by the gas pressure generated in the combustion chamber (10). The top dead center ring (4) pushed to the point side slides toward the cylinder wall (7) along the contact surface (5) of the lower point ring (5), and the top dead center side ring (4) Is pressed against the cylinder wall (7), and the sealing performance of the pressure ring (3) can be improved.

(Invention of Claim 2)
The invention according to claim 2 has the following effect in addition to the effect of the invention according to claim 1.
<Effect> The frictional resistance of the pressure ring against the cylinder wall can be reduced.
As illustrated in FIG. 1B, since the outer peripheral surface (5b) of the bottom dead center side ring (5) is separated from the cylinder wall (7), the pressure ring (3) and the cylinder wall (7) , The frictional resistance of the pressure ring (3) against the cylinder wall (6) can be reduced.

(Invention of Claim 3)
The invention according to claim 3 has the following effect in addition to the effect of the invention according to claim 1 or claim 2.
<Effect> The cooling efficiency of the piston head can be increased.
Since the top dead center ring (4) is made of a material having higher thermal conductivity than the bottom dead center ring (5), the heat of the piston head (1) is high thermal conductivity. It is transmitted to the cylinder wall (7) via (4), and the cooling efficiency of the piston head (1) can be increased.

(Invention of Claim 4)
The invention according to claim 4 has the following effects in addition to the effects of the invention according to any one of claims 1 to 3.
<Effect> The cooling efficiency of the piston head can be increased.
As illustrated in FIG. 1B, since the pressure ring (3) is fitted in the ring groove (2) on the top dead center side, the piston top surface is heated by the heat of the piston head (1). It is conducted to the cylinder wall (7) through the top dead center side ring (4) closest to (1a), and the cooling efficiency of the piston head (1) can be enhanced.

<Effect> The sealing performance of the pressure ring can be improved.
As illustrated in FIG. 1B, since the pressure ring (3) is fitted in the ring groove (2) on the top dead center side, the gas pressure generated in the combustion chamber (10) is top dead. Directly received by the point side ring (4), the top dead center side ring (4) is strongly pressed against the cylinder wall (7), and the sealing performance of the pressure ring (3) is enhanced.

(Invention according to claim 5)
The invention according to claim 5 has the following effect in addition to the effect of the invention according to claim 4.
<Effect> A piston having a simple structure can be used.
As illustrated in FIG. 1B, since the land portion (9) without the ring groove is formed between the ring groove (2) and the oil ring groove (8), an intermediate ring groove such as a second ring is provided. It is possible to use a piston (11) having a simple structure without the above.

(Invention of Claim 6)
The invention according to claim 6 has the following effects in addition to the effects of the invention according to any one of claims 1 to 5.
<Effect> The sealing performance of the pressure ring can be improved.
As illustrated in FIG. 2, the gaps (4c) (5c) between the top dead center side ring (4) and the bottom dead center side ring (5) are shifted from each other in the circumferential direction of the pressure ring (3). Since the bottom dead center side ring (5) or the top dead center side ring (4) overlapped with each gap gap (4c) (5c), each gap gap (4c) (5c) The blow-by gas can be prevented from being blown through, and the sealing performance of the pressure ring (3) can be improved.

(Invention of Claim 7)
The invention according to claim 7 has the following effect in addition to the effect of the invention according to claim 6.
<Effect> The sealing performance of the pressure ring can be improved.
As illustrated in FIG. 2, the gaps (4c) (5c) between the top dead center ring (4) and the bottom dead center ring (5) are opposite to each other in the radial direction of the piston head (1). The blow-by gas that has passed through the joint gap (4c) of the top dead center side ring (4) passes through the ring groove (2) to the opposite side of the cylinder head (1) in the radial direction. If it does not reach, it will not reach the joint gap (5c) of the bottom dead center side ring (5), and blow-by gas blow-through through the ring groove (2) can be suppressed, and the pressure ring (3) is sealed. Can increase the sex.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a diesel engine according to an embodiment of the present invention, in which FIG. 1 (A) is a schematic view of a main part, and FIG. 1 (B) is an enlarged longitudinal sectional view of a piston and a cylinder wall. It is the II-II sectional view taken on the line of FIG.

  FIGS. 1 and 2 are views for explaining an engine according to an embodiment of the present invention. In this embodiment, a direct injection vertical diesel engine will be described.

The outline of this engine is as follows.
As shown in FIG. 1 (A), in this engine, a cylinder head (12) is assembled on an upper portion of a cylinder wall (7), and a piston (11) is fitted in a cylinder bore. The piston (11) is connected to the crankshaft (14) via a connecting rod (13).
The cylinder head (12) is provided with an intake port (15) and an exhaust port (16), and a fuel injector (17) is attached.
The injection port of the fuel injector (17) is directed to the combustion chamber (10) surrounded by the cylinder head (12), the cylinder wall (7), and the piston (11).

  As shown in FIG. 1 (B), in this engine, the pressure ring (3) is fitted in the ring groove (2) of the piston head (1), and the pressure ring (3) overlaps the top dead center. It consists of a side ring (4) and a bottom dead center ring (5), and the contact surface (4a) (5a) between the top dead center ring (4) and the bottom dead center ring (5) is the cylinder center axis. It is comprised so that it may incline with respect to the direction parallel to (6).

As shown in FIG. 1B, in this engine, the contact surfaces (4a) and (5a) of the top dead center side ring (4) and the bottom dead center side ring (5) are formed on the cylinder wall (7). As it approaches, it is inclined so as to approach the bottom dead center side, and the outer peripheral surface (4b) of the top dead center side ring (4) is in contact with the cylinder wall (7).
As shown in FIG. 1B, in this engine, the outer peripheral surface (5b) of the bottom dead center side ring (5) is separated from the cylinder wall (7).
As shown in FIG. 1 (B), this engine has a bottom dead center side extended from the contact surface (4a) toward the cylinder wall (7) toward the bottom dead center side of the top dead center ring (4). comprises an extension surface (4e), acute edge portion toward the bottom dead center to the corners of the outer peripheral surface (4b) and the bottom dead center side extension surface of the top dead center ring (4) (4e) (4d ) Is formed.

In this engine, the top dead center side ring (4) is made of a material having higher thermal conductivity than the bottom dead center side ring (5).
An inexpensive cast iron is used for the bottom dead center side ring (5).
For the top dead center ring (4), alloy steel having higher thermal conductivity than the bottom dead center ring (5) is used. The surface of the alloy steel may be subjected to hard chrome plating with high thermal conductivity.

  As shown in FIG. 1B, in this engine, the pressure ring (3) is fitted in the ring groove (2) closest to the top dead center.

As shown in FIG. 1B, in this engine, a land portion (9) having no ring groove is formed between the ring groove (2) and the oil ring groove (8).
An oil ring (18) is fitted in the oil ring groove (8).

  As shown in FIG. 2, in this engine, the joint gaps (4c) and (5c) of the top dead center side ring (4) and the bottom dead center side ring (5) are mutually connected to the circumference of the pressure ring (3). Arranged to be shifted in the direction.

  As shown in FIG. 2, in this engine, the gaps (4c) (5c) between the top dead center side ring (4) and the bottom dead center side ring (5) are arranged in the radial direction of the ring groove (2). They are arranged on opposite sides.

(1) Piston head
(2) Ring groove
(3) Pressure ring
(4) Top dead center ring
(4a) Contact surface
(4b) Outer surface
(4c) Aperture gap
(5) Bottom dead center ring
(5a) Contact surface
(5b) Outer peripheral surface
(5c) Opening gap
(6) Cylinder center axis
(7) Cylinder wall
(8) Oil ring groove
(9) Land

Claims (7)

The pressure ring (3) is fitted in the ring groove (2) of the piston head (1), and the pressure ring (3) is overlapped with the top dead center side ring (4) and the bottom dead center side ring (5). The contact surfaces (4a) and (5a) of the top dead center ring (4) and the bottom dead center ring (5) are inclined with respect to a direction parallel to the cylinder center axis (6). In the configured engine,
The mutual contact surfaces (4a) and (5a) of the top dead center ring (4) and the bottom dead center ring (5) are inclined so as to approach the bottom dead center side as they approach the cylinder wall (7). The outer peripheral surface (4b) of the top dead center ring (4) is in contact with the cylinder wall (7),
A bottom dead center side extended surface (4e) extended from the contact surface (4a) toward the cylinder wall (7 ) is provided on the bottom dead center side of the top dead center side ring (4). An engine having an acute edge portion (4d) toward the bottom dead center side formed at a corner portion of the outer peripheral surface (4b) and the bottom dead center side extension surface (4e) of 4). The engine according to claim 1,
An engine characterized in that an outer peripheral surface (5b) of a bottom dead center ring (5) is separated from a cylinder wall (7). The engine according to claim 1 or 2,
The engine characterized in that the top dead center ring (4) is made of a material having higher thermal conductivity than the bottom dead center ring (5). The engine according to any one of claims 1 to 3,
The engine, wherein the pressure ring (3) is fitted in the ring groove (2) closest to the top dead center. The engine according to claim 4, wherein
An engine characterized in that a land portion (9) having no ring groove is formed between the ring groove (2) and the oil ring groove (8). The engine according to any one of claims 1 to 5,
The gap gaps (4c) and (5c) of the top dead center ring (4) and the bottom dead center ring (5) are arranged so as to be shifted from each other in the circumferential direction of the pressure ring (3). A featured engine. The engine according to claim 6, wherein
The gaps (4c) (5c) between the top dead center side ring (4) and the bottom dead center side ring (5) are arranged on the opposite sides in the radial direction of the piston head (1). A featured engine.

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