JPH11280537A - Cylinder block for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve sound insulation of an engine noise. SOLUTION: In a cylinder block of wet liner type, block outer walls 17, 18 are formed respectively in an outer side of a water jacket outer wall 15 along a cylinder arrangement direction in both side, surfaces of the cylinder block, a double wall structure is provided, an interval between one water jacket outer wall 15 and the block outer wall 17 is formed as a cooling water passage space 19, and an interval between the other water jacket outer wall 15 and the block outer wall 18 is formed as an oil return space 20 returning oil from a cylinder head side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cylinder block for an internal combustion engine.

[0002]

2. Description of the Related Art In a cylinder block using a wet type cylinder liner, a water jacket is formed on the outer periphery of the cylinder liner, and the water jacket is cooled by a cooling water passage provided on an outer wall of the water jacket along a cylinder arrangement direction. Water is being introduced.

[0003] Further, in such a cylinder block, an outer wall is further formed outside the outer wall of the water jacket,
It is considered that oil from the cylinder head side is returned to the oil pan side through the space therebetween (Japanese Utility Model Laid-Open No. 6-63825). Also, Japanese Patent Application Laid-Open No. 9-209
Nos. 821 and 6-66199 are also known,
Each of these is a technology of a cylinder block using a dry type liner and is irrelevant to the present application.

[0004]

However, in the cylinder block disclosed in Japanese Utility Model Application Laid-Open No. 63825/1994, the outer wall is provided outside the outer wall of the water jacket on one side, so that engine noise is reduced. However, on the other side, since the outer wall of the water jacket is the outer wall of the block, there is a problem that the noise of the engine is emitted accordingly.

An object of the present invention is to solve such a problem.

[0006]

According to a first aspect of the present invention, there is provided a cylinder block of an internal combustion engine in which a water jacket is formed around a wet type cylinder liner to be inserted. The outer wall of the water jacket along the outer wall is formed to form a double wall structure, a space between one outer wall of the water jacket and the outer wall of the block is a cooling water passage space to the water jacket, and the other water jacket is formed. An oil return space for returning oil from the cylinder head side is provided between the outer wall and the block outer wall.

In a second aspect based on the first aspect, the cooling water passage space is provided on an exhaust path side of the engine.

[0008]

According to the first aspect of the invention, the sound insulation of the engine sound is improved, and the engine noise can be sufficiently reduced. Also,
Since the outer wall of the block is further provided outside the outer wall of the water jacket to form a double wall structure, the rigidity is increased as a whole, and vibration can be reduced.

According to the second aspect of the present invention, it is possible to secure good cooling performance of a portion having a large thermal load on the exhaust side of the cylinder block on the exhaust side.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 to FIG. 3 show a cylinder block 10 of a diesel engine.

The cylinder block 10 has an insertion opening 12 for a wet-type cylinder liner 11 on the upper surface of the block so that the cylinders are arranged in the block longitudinal direction.
Are formed, and the inserted cylinder liners 11 are supported by the insertion opening 12 and the inner annular portions 13 and 14, respectively.

Around each of the cylinder liners 11,
A water jacket 16 is formed on the outer periphery of the cylinder liner 11 by a water jacket outer wall 15 formed from the opening end of the insertion port 12 to the annular portion 14. Water jacket outer wall 1 between adjacent cylinders
5 is formed integrally.

Block outer walls 17 and 18 are formed on both sides of the cylinder block 10 outside the water jacket outer wall 15 along the cylinder arrangement direction to form a double wall structure.

The space between the water jacket outer wall 15 on one side and the block outer wall 17 is in a cooling water passage space 19 to the water jacket 16, and the space between the other water jacket outer wall 15 and the block outer wall 18 is from the cylinder head side. An oil return space 20 for returning oil is formed.

The cooling water passage space 19 is formed on the exhaust side (exhaust path side) of each cylinder. A cooling water inlet 21 for guiding cooling water from a water pump to the cooling water passage space 19 is provided at a predetermined position on the block outer wall 17 of the cooling water passage space 19, and the water jacket outer wall 15 facing the cooling water passage space 19 is provided. Are formed with openings 22 for guiding the cooling water entering the cooling water passage space 19 to the water jacket 16. Although not shown, cylinder block 1
0 cooling water passage space 19 and water jacket 1
In the upper part of 6, a guide hole for sending the cooling water in the cooling water passage space 19 and the water jacket 16 to the cylinder head side is formed.

The oil return space 20 is formed on the intake side (intake path side) of intake air of each cylinder. An oil drop hole (not shown) for dropping oil from the cylinder head side is formed in the upper part of the oil return space 20 of the cylinder block 10. An oil escape hole 23 for escape to the pan side is formed.

In the figure, reference numeral 25 denotes a bearing portion of the crankshaft;
Reference numeral 6 denotes a skirt, and reference numerals 27 and 28 denote an oil gallery and the like.

As described above, since the block outer walls 17, 18 are formed on both sides of the cylinder block 10 on the outer side of the water jacket outer wall 15 along the cylinder arranging direction to form a double wall structure, the engine sound is accurate. The engine noise is sufficiently reduced. Further, outside the water jacket outer wall 15, a block outer wall 17,
18 and the double wall structure, the rigidity is increased as a whole, and vibration can be reduced.

Further, since the cooling water passage space 19 filled with cooling water is formed on the exhaust path side of the engine, good cooling performance of a portion on the exhaust discharge side of the cylinder block 10 where the heat load is large is ensured. You.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view passing through the center of a cylinder showing an embodiment.

FIG. 2 is a sectional view between cylinders.

FIG. 3 is a cross-sectional view in a cylinder row direction.

[Explanation of symbols]

 Reference Signs List 10 Cylinder block 11 Cylinder liner 15 Water jacket outer wall 16 Water jacket 17, 18 Block outer wall 19 Cooling water passage space 20 Oil return space 21 Cooling water inlet 22 Opening 23 Oil escape hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02F 7/00 301 F02F 7/00 301B

Claims (2)

[Claims] 1. A cylinder block of an internal combustion engine having a water jacket formed around a wet-type cylinder liner to be inserted, wherein the cylinder block is provided on both side surfaces of the cylinder block and outside of a water jacket outer wall along a cylinder arrangement direction. The outer wall is formed to have a double wall structure, a space between one water jacket outer wall and the block outer wall is a cooling water passage space to the water jacket, and a cylinder head is formed between the other water jacket outer wall and the block outer wall. A cylinder block for an internal combustion engine, wherein an oil return space for returning oil from a side is provided. 2. The cylinder block according to claim 1, wherein the cooling water passage space is provided on an exhaust path side of the engine.