JP2004285990A - Cylinder block with cooling fin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylinder block with a cooling fin for improving cooling performance by forming the cooling fin in a water gallery of the cylinder block. <P>SOLUTION: In this cylinder block 1 of an engine, a cooling fin 5 with indentations and projections is formed to a wall face 4 on a cylinder 3 side of a water gallery 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for improving the cooling performance of a cylinder block of an engine.
[0002]
[Prior art]
As a feature of the diesel engine, the magnitude of vibration and noise due to piston slap during combustion is a problem. As a countermeasure against such a problem, a method of increasing the thickness of the side surface of the cylinder block has been adopted. There is a problem that it can also cause burn-in.
[0003]
Here, a coolant passage for cooling is formed in the cylinder block (for example, see Non-Patent Document 1).
[0004]
Another conventional technique is a cooling device for an internal combustion engine in which a heat insulating member is provided inside a water jacket having a structure capable of storing a cooling liquid and contacting the outer peripheral wall surface of the cylinder barrel, the heat insulating member being a cylinder barrel. There is a technique in which the inner wall surface of the water jacket except for the outer peripheral wall surface is covered, and at least a part of the heat insulating member is connected to a cylinder head gasket (for example, see Patent Document 1).
However, this technique aims to improve the warm-up property of the engine and reduce the emission of harmful substances (low-temperature emissions) from the engine, and does not solve the above-mentioned problems.
[0005]
[Non-patent document 1]
Maintenance Instructions NISSAN Terrano R50 Type Car (Supplement 3) EM70
[Patent Document 1]
JP-A-2001-20738.
[0006]
[Problems to be solved by the invention]
The present invention has been proposed in view of the above-described conventional problems, and has as its object to provide a cylinder block with cooling fins that improves cooling performance by forming cooling fins in a water gallery of a cylinder block. I have.
[0007]
[Means for Solving the Problems]
In the cylinder block with cooling fins of the present invention, in the engine cylinder block (1), uneven cooling fins (5, 5A, 5B, 5C, 5D) are provided on the cylinder side wall (4) of the water gallery (2). It is characterized by being formed.
[0008]
The cooling fins (5, 5A) are formed unevenly in the vertical direction (claim 2).
[0009]
Thus, the cooling fins (5, 5A) are formed on the cylinder-side wall surface (4) in the vertical direction so that the cooling fins (5, 5A) are provided on the surface of the water gallery (2), particularly on the side closer to the heat source. (Radiation area) is greatly increased, and cooling performance is improved. That is, even if the thickness of the cylinder wall (4) is slightly increased for measures against vibration and noise, the cooling performance is improved.
[0010]
It is preferable that the cooling fin (5A) is formed such that the upper and lower portions of the cooling fins have large unevenness and the amount of unevenness decreases as going downward.
As described above, by increasing the size and pitch of the unevenness toward the upper side of the cylinder, that is, the upper side of the water gallery 2, and increasing the heat radiation surface area, it is possible to further improve the cooling performance above the cylinder exposed to high temperatures. I can do it.
[0011]
The cooling fins (5B, 5C, 5D) are formed with irregularities along the cylinder wall (4).
[0012]
By forming the irregularities (cooling fins 5B) along the cylinder wall (4) as described above, the area of the region where the cooling water flows (radiation area) can be increased, and the cooling performance can be improved appropriately. I can do it.
[0013]
It is preferable that the cooling fins (5C) are formed so that the unevenness on the downstream side of the cooling water is large and the amount of unevenness is reduced toward the upstream side.
In this way, the upstream side of the flow, which is easily affected by the flow, has a small unevenness amount with low resistance, and the downstream side, which is not easily affected by the flow, has a large unevenness amount to gain a heat dissipation area, so cooling while suppressing increase in resistance Performance can be improved.
[0014]
The cooling fin (5D) is formed with irregularities so as to protrude upstream of the cooling water (claim 4).
[0015]
In this way, by forming the irregularities (5D) so as to protrude to the upstream side of the cooling water, the cooling water can be positively captured on the concave side (5d) and sufficient heat exchange can be performed with the cooling water. As a result, the cooling performance is improved.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0017]
First, before describing the embodiment, the flow of cooling water for the engine will be briefly described with reference to FIGS. 8 and 9.
[0018]
In FIG. 8, the cooling system of the engine E is such that when the engine E starts, the cooling fan F rotates, and when the wind generated by the rotation of the cooling fan F passes through the radiator R, the engine cooling water flowing through the radiator R is cooled. It is.
The engine cooling water cooled by the radiator R is sucked into the water gallery 2 of the cylinder block 1 by the water pump P via the lower hose H1 (see FIG. 9). The arrows in FIGS. 8 and 9 indicate the flow of the cooling water.
[0019]
In the process in which the cooling water flows through the water gallery 2 of the cylinder block 1, combustion heat is taken from the cylinder wall 4, that is, the cylinder wall 4 is cooled. It flows upward toward the outlet with the thermostat S interposed.
[0020]
The outlet through which the thermostat S is interposed is connected to the suction port Ra of the radiator R by an upper hose H2, and the cooling water warmed in the engine (water gallery 2) returns to the radiator R from the suction port Ra again. And repeat the same cycle.
[0021]
Here, as described above, in FIG. 9, which is a horizontal cross section of the cylinder block 1, a portion indicated by reference numeral 50 may be thickened to prevent piston slap.
[0022]
The first embodiment of FIGS. 1 and 2 will be described below in order to eliminate the deterioration of the cooling performance which can occur when the wall surrounding the cylinder is laid as above to take measures to reduce vibration and noise. This is an embodiment in which uneven cooling fins 5 are formed in the vertical direction of the wall surface 4 on the cylinder 3 side.
[0023]
In FIG. 1, cooling fins (irregularities) 5 having irregularities are formed vertically on a wall surface 4 of the water gallery 2 adjacent to the cylinder 3 on the cylinder 3 side. Since the cooling fins 5 greatly increase the surface (radiation area) of the water gallery 2 particularly on the side close to the heat source, the cooling performance is greatly improved. That is, even if the thickness of the cylinder wall 4 is slightly increased for measures against vibration and noise, the cooling performance is rather improved.
[0024]
The difference between FIGS. 1 and 2 is that the first embodiment shown in FIG. 1 has the same size and pitch of the peaks and valleys of the cooling fins (concavities and convexities) 5, whereas the other embodiments of FIG. The size of the concavities and convexities is increased toward the upper side of the cylinder, that is, the upper side of the water gallery 2, so as to increase the heat radiation surface area and to further improve the cooling performance above the cylinder 1 exposed to a high temperature.
Although not shown in FIGS. 1 and 2, the cooling water flows in the front and back directions on the paper.
[0025]
Next, a second embodiment will be described with reference to FIGS.
FIG. 3 is a longitudinal sectional view of a main part of the second embodiment, and FIG. 4 is a sectional view taken along line XX of FIG. 3 (a horizontal sectional view corresponding to FIG. 9 as a prior art).
Here, from the FIG. 4 to the third embodiment of FIG. 7, the arrows attached to the drawings indicate the flow of the cooling water.
[0026]
In FIG. 4, cooling fins (irregularities) 5 </ b> B are formed along the cylinder wall 4. FIG. 5 shows a first example of the second embodiment, and is an enlarged drawing of one portion of the cylinder of FIG. 4, in which all the cooling fins 5B are formed with the same amount of unevenness and the same pitch. .
4 and 5, the two-dot line indicates the shape of the cylinder wall before the cooling fin is provided.
By forming the cooling fins 5B along the cylinder wall 4 as described above, the area of the region where the cooling water flows (radiation area) is increased, and the cooling performance can be suitably improved. .
[0028]
In the first example of the second embodiment of FIG. 5, the cooling fins 5B are all formed with the same unevenness. On the other hand, in another example of the second embodiment shown in FIG. 6, the unevenness (h1) of the cooling fin 5C is large on the downstream side of the cooling water, and the unevenness (h2) is reduced toward the upstream side. ing.
In this way, the upstream side of the flow, which is easily affected by the flow, has a small unevenness amount with low resistance, and the downstream side, which is not easily affected by the flow, has a large unevenness amount to gain a heat dissipation area, so cooling while suppressing increase in resistance Performance can be improved.
[0029]
FIG. 7 is a diagram illustrating a shape of a cooling fin according to the third embodiment.
The cooling fins 5D are formed with irregularities so as to protrude upstream of the flow of the cooling water.
[0030]
In this way, by forming the unevenness so as to protrude to the upstream side of the cooling water, the cooling water can be positively captured on the concave side 5d, and the cooling water can be sufficiently exchanged with heat. Is improved.
[0031]
【The invention's effect】
The effects of the present invention are listed below.
(A) By forming cooling fins having irregularities in the vertical direction on the wall surface on the cylinder side, the surface (radiation area) of the water gallery, particularly on the side near the heat source, is greatly increased, and the cooling performance is greatly improved. In other words, even if the thickness of the cylinder wall is slightly increased for measures against vibration and noise, the cooling performance is improved rather.
(B) The cooling performance above the cylinder exposed to high temperatures can be further improved by increasing the size of the unevenness toward the upper side of the cylinder, that is, the upper side of the water gallery, thereby increasing the heat radiation surface area.
(C) By forming the projections and depressions (cooling fins) along the cylinder wall, the area of the region where the cooling water flows (radiation area) is increased, and the cooling performance can be suitably improved.
(D) The cooling fins have a small unevenness on the upstream side of the flow that is susceptible to the flow with a small amount of resistance and a large unevenness on the downstream side that is less susceptible to the flow. While improving the cooling performance.
(E) By forming irregularities so as to protrude to the upstream side of the cooling water, the cooling water can be positively captured on the concave side, and the cooling water can be sufficiently exchanged with heat, thereby improving the cooling performance. I do.
[Brief description of the drawings]
FIG. 1 is a sectional view of a main part according to a first example of the first embodiment of the present invention.
FIG. 2 is a sectional view of a main part according to another example of the first embodiment of the present invention.
FIG. 3 is a longitudinal sectional view of a main part according to a second embodiment of the present invention.
FIG. 4 is a horizontal sectional view of a main part according to a first example of the second embodiment of the present invention.
FIG. 5 is an enlarged sectional view of a main part according to a first example of the second embodiment of the present invention.
FIG. 6 is an enlarged sectional view of a main part according to another example of the second embodiment of the present invention.
FIG. 7 is an enlarged sectional view of a main part according to a third embodiment of the present invention.
FIG. 8 is an engine schematic diagram for explaining the flow of engine cooling water.
FIG. 9 is a sectional view taken along line XX of FIG. 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cylinder block 2 ... Water gallery 3 ... Cylinder 4 ... Cylinder wall 5, 5A, 5B, 5C ... Concavo-convex / cooling fin 5d ... Concave side

Claims (4)

A cylinder block with cooling fins, wherein an uneven cooling fin is formed on a wall of a cylinder of a water gallery in a cylinder block of an engine. 2. The cylinder block with cooling fins according to claim 1, wherein the cooling fins are formed to have irregularities in a vertical direction. 2. The cylinder block with cooling fins according to claim 1, wherein the cooling fins are formed with irregularities along the cylinder wall. 4. The cylinder block with cooling fins according to claim 3, wherein the cooling fins are formed with irregularities so as to protrude upstream of the cooling water.

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