JPH0674090A - Cooling device for engine - Google Patents

Abstract

PURPOSE:To uniformize temperature distribution in the peripheral direction of a cylinder liner. CONSTITUTION:An independent cooling water passage 1 formed in a cylindrical shape is formed at each cylinder of an engine by using the outer wall surface of a cylinder liner 9 and the inner wall surface 4a of a cylinder block. The cooling water inflow and outflow ports 2 and 3 of the cooling water passage 1 are arranged with the axis of the cylinder therebetween in a state to be positioned facing each other. A narrow passage part 8 is formed between an intermediate point, situated between the cooling water inflow and outflow ports 2 and 3 of the cooling water passage 1, and the cooling water outflow port 3. Thus, since the velocity of flow of cooling water is increased at the narrow passage part 8, the cooling efficiency of the portion, ranging from the intermediate point to the cooling water outflow port 3, of the cylinder liner 9 is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling device.

[0002]

2. Description of the Related Art A cooling water passage of a cylinder liner formed by an outer wall surface of an engine cylinder liner and an inner wall surface of a cylinder block is provided for each cylinder in order to obtain a stable engine output by reducing variations in cooling of each cylinder. The technique of making it independent is known.

Further, as illustrated in FIG. 22, the engine a includes a cylinder block b, a cylinder head c, a crankcase d, an air supply / exhaust portion e and a cooling water pump f.
Etc. are laid out respectively.

The respective positions of the cooling water inlet and the cooling water outlet in the cooling water passage avoid the benefits of filling the cooling water passage with cooling water and the positions of the bolts for tightening the cylinder block b and the cylinder head c. Cooling water pump f
In consideration of the benefits of installing the cooling water, it is advantageous to dispose the cooling water inlet at the bottom dead center side of the cylinder block and the cooling water outlet at the top dead center side of the cylinder block.

By the way, the flow pattern of the cooling water flowing through the cooling water passage of the cylinder liner as described above is as follows.
As shown in the flow pattern diagram of FIG. 17 which is a combination of the plan view of the cooling water passage and the development view of the cooling water passage, the main flow of the cooling water flowing from the cooling water inlet port g into the cooling water passage h is below the cylinder liner. It flows so as to pass through the dead point side (lower layer) and be discharged from the cooling water outlet i. Note that in FIG. 23, m
Is a cooling water retention zone, and v is a high-speed circulation part of the cooling water.

Therefore, as shown in the distribution diagram of the heat transfer of FIG. 24, the heat transfer contributing to the cooling along with the main flow of the cooling water is also near the cooling water inlet g and the cylinder liner of the cooling water passage h. It becomes the good heat transfer zone j on the bottom dead center side of the cooling water inlet (0 degree position) and the cooling water outlet (180
The range from the intermediate point (90 degree position) to the approximately 150 degree position is the low heat transfer zone k. The low heat transfer zone k is caused by the generation of the retention zone m of the cooling water and the separation of the cooling water from the outer wall surface of the cylinder liner (the flow of the cooling water occurs at a position apart from the outer wall surface). .

Further, when the collective trend of the heat transfer coefficient based on the flow pattern of the cooling water is viewed in the cross-sectional direction of the cylinder liner, as shown in FIG. 25 showing a typical heat transfer coefficient distribution. The cooling water generates a stationary zone as described above in the range from the midpoint between the cooling water inlet and the cooling water outlet to the cooling water outlet, particularly in the range between the 90 degree position and the 150 degree position, and It can be seen that the heat transfer coefficient is greatly reduced by peeling off from the outer wall surface of the cylinder liner, and the low heat transfer zone k is formed. In addition, in order to efficiently cool the top dead center side of the cylinder liner, the cylinder head side cooling water passage and the cylinder block side cooling water passage have two separate systems, and the cylinder liner top dead center side cooling is performed. It is proposed in Japanese Utility Model Application Laid-Open No. 61-57124 that the cooling water passage is provided on the cylinder head side.

[0008]

The conventional cooling water in the cooling water passage has the above-mentioned behavior,
In the latter half after the 90 ° position, which is the midpoint between the cooling water inlet and the cooling water outlet, the heat dissipation by the cooling water is greatly reduced, and the cooling performance of the cylinder liner in the above portion deteriorates. Therefore, on the top dead center side of the cylinder liner, there is a temperature difference between the first half and the second half of the intermediate point between the cooling water inlet and the cooling water outlet, so that the cooling of the cylinder liner in the circumferential direction becomes uneven. As a result, the cylinder liner has problems such as thermal deformation or deterioration of performance due to knocking.

Further, in the cooling water passage mechanism disclosed in Japanese Utility Model Laid-Open No. 61-57124, the cooling water introduced into the cooling water passage on the cylinder head side collectively cools a plurality of cylinders. The cooling of each cylinder liner varies, and it may be difficult to uniformly cool the individual cylinder liners in the circumferential direction due to the flow state of the cooling water.

On the other hand, in a multi-cylinder engine, heat is transferred from the cylinders adjacent to each other to adjacent parts of the cylinders, and heat radiation to the outside is reduced. It is easy for the temperature to become higher than that of the side part. Therefore, in the cylinder located at the end portion in the cylinder row direction, the temperature distribution in the circumferential direction of the cylinder liner becomes more uneven than in the other cylinders, and the problems of thermal deformation and knocking of the cylinder liner become more prominent. Is coming.

In view of the above, according to the present invention, in the cooling water passage of the engine in which the cooling water passage is independently provided for each cylinder, the cooling water is separated from the outer wall surface of the cylinder liner and the cooling water retention zone is formed. An object of the present invention is to provide an engine cooling water device capable of uniformly cooling the top dead center side of a cylinder liner in the entire circumferential direction by suppressing the occurrence of the occurrence or the like.

[0012]

In order to solve the above problems, the invention of claim 1 provides a cooling water passage provided independently for each cylinder rather than an intermediate point between the cooling water inlet and the cooling water outlet. In the latter half area, the cooling performance is improved by increasing the flow rate of the cooling water, and the cooling of the cylinder liner in the above area is promoted.

In the present invention, the intermediate point is
The position does not mean only the 90-degree position, but may be a position shifted in the front and rear thereof. Regarding the outer wall surface of the cylinder liner, the outer peripheral surface of the cylinder liner itself constitutes the outer wall surface in the case of a wet type, but the outer peripheral surface of the liner fitting portion of the cylinder block in which the cylinder liner is fitted in the case of a dry type. It constitutes the outer wall surface. These points are the same in the inventions of other claims.

Specifically, in the means for solving the problems of the first aspect of the invention, the cylindrical cooling water passage formed by the outer wall surface of the cylinder liner and the inner wall surface of the cylinder block is provided independently for each cylinder. The cooling water inlet and the cooling water outlet of the cooling water passage are provided at positions substantially opposite to each other with respect to the axis of the cylinder, that is, with the axis of the cylinder facing each other, and the cooling water flow in the cooling water passage. It is characterized in that a narrow passage portion having a narrower passage width than other portions is provided between an intermediate point between the inlet and the cooling water outlet and the cooling water outlet.

Further, the invention of claim 2 is intended to form a narrow passage portion in a required portion in the cooling water passage by a simple processing applied to the cylinder block. 2. The structure according to claim 1, wherein the narrow passage portion is formed by a bulging portion provided on the inner wall surface of the cylinder block so as to bulge into the cooling water passage and extends from the top dead center side toward the bottom dead center side. It is characterized in that it is done.

Further, in the invention of claim 3, the width of the narrow passage formed in the cooling water passage is changed between the top dead center side and the bottom dead center side of the cylinder liner so that the top dead center side is changed. An attempt is made to increase the amount of cooling water that can flow. Specifically, in the configuration of claim 2, the bulging portion expands more on the bottom dead center side than on the top dead center side. It is characterized in that it is formed so as to have a large output.

Further, according to the invention of claim 4, the heat radiation from the cylinder liner to the cooling water is partially different, so that the cooling water passage can be provided in the cooling water passage at an intermediate point between the cooling water inlet and the cooling water outlet. It is intended to facilitate cooling on the top dead center side of the cylinder liner facing the area, thereby making uniform the cooling performance in the circumferential direction.

Specifically, in the means for solving the problems of the fourth aspect of the invention, a cylindrical cooling water passage formed by the outer wall surface of the cylinder liner and the inner wall surface of the cylinder block is provided independently for each cylinder. The cooling water inlet and the cooling water outlet of the cooling water passage are provided at positions substantially opposite to each other with respect to the axis of the cylinder, and the cylinder liner has an intermediate point between the cooling water inlet and the cooling water outlet in the cooling water passage. It is characterized in that a heat radiating portion having a higher heat radiating property than the other portions is provided in a portion of the region from to the cooling water outlet.

According to the invention of claim 5, a turbulent flow is generated in the cooling water in the region of the latter half from the midpoint between the cooling water inlet and the cooling water outlet of the cooling water passage, and the turbulent flow is generated on the cooling water passage. It is intended to enhance the cooling performance by interfering with the cooling water flowing through the end portion on the dead point side.

Specifically, in the means for solving the problems according to the invention of claim 5, a cylindrical cooling water passage formed by an outer wall surface of the cylinder liner and an inner wall surface of the cylinder block is provided independently for each cylinder. The cooling water inlet and the cooling water outlet of the cooling water passage are provided at positions substantially opposite to each other with respect to the axis of the cylinder, and the cooling water flow is provided from an intermediate point between the cooling water inlet and the cooling water outlet in the cooling water passage. It is characterized in that a turbulent flow generating portion for generating a turbulent flow in the cooling water in the cooling water passage is provided in a region up to the outlet.

Further, in the invention of claim 6, in the region from the middle point between the cooling water inlet and the cooling water outlet of the cooling water passage to the latter half, the central part of the top dead center side and the bottom dead center side of the cylinder liner is formed. Guide the main flow of circulating cooling water toward the top dead center side,
By making it merge with the cooling water flowing on the side of the top dead center, the flow rate on the side of the top dead center in the above-mentioned region is increased, thereby enhancing the cooling performance.

Specifically, in the solution means set forth in claim 6, a cylindrical cooling water passage formed by an outer wall surface of the cylinder liner and an inner wall surface of the cylinder block is provided independently for each cylinder, and the cooling is performed. The cooling water inflow port and the cooling water outflow port of the water passage are provided at positions substantially opposite to each other with respect to the axis of the cylinder, and the region from the midpoint between the cooling water inflow port and the cooling water outflow port in the cooling water passage to the cooling water outflow port. It is characterized in that a cooling water guiding portion for guiding the cooling water flowing through the cooling water passage to the top dead center side is provided at the center of the top dead center side and the bottom dead center side.

The invention of claim 7 relates to a cooling water passage for a cylinder arranged at an end portion in the cylinder row direction, and improves the cooling performance on the inter-cylinder side of the cylinder liner by providing an appropriate passage resistance. is there.

Specifically, the means taken by the invention of claim 7 is the cooling water flow of the cooling water passage of the cylinder arranged at the end portion in the cylinder row direction in each invention of claims 1 to 6. The inlet and the cooling water outlet are provided so as to substantially oppose each other in a direction intersecting with the cylinder row direction, and the cooling water passage is provided in the cooling water passage from the cooling water inlet to the adjacent cylinder. The amount of cooling water flowing through the inter-cylinder side path leading to the outlet is larger than the amount of cooling water flowing through the anti-cylinder side path that goes from the cooling water inlet to the side opposite to the adjacent cylinder and reaches the cooling water outlet. It is characterized by the passage resistance.

[0025]

According to the invention of claim 1, since the narrow passage is provided in the region from the intermediate point between the cooling water inlet and the cooling water outlet in the cooling water passage to the cooling water outlet, the narrow passage is provided in the narrow passage. Since the problem of separation of the cooling water is reduced and the flow velocity of the cooling water is increased, the cooling performance is improved from the intermediate point (for example, about 90 degrees position) of the cylinder liner to the latter half.

Further, in the invention of claims 2 to 3, since the narrow passage portion of the cooling water passage is formed by the bulging portion provided on the inner wall surface of the cylinder block, the cooling water is selected by selecting the width of the narrow passage portion. It becomes easy to set the flow velocity to the required value.

Further, in the case of the invention of claim 3, since the narrow path portion is narrower on the bottom dead center side than on the top dead center side of the cylinder liner, the cooling water flowing on the top dead center side of the region is Since the flow rate is increased as compared with other regions, the cooling performance on the top dead center side of the latter half of the cylinder liner is further improved.

Further, since the bulging portion provided on the inner wall surface of the cylinder block to form the narrow passage portion is provided on the inner wall surface of the cylinder block and extends from the top dead center side toward the bottom dead center side, it also functions as a reinforcing rib. To do.

Further, in the case of the invention of claim 4, the cylinder liner portion in the region from the midpoint between the cooling water inlet and the cooling water outlet of the cooling water passage to the cooling water outlet has a higher heat radiation property than the other portions. Since this is large, the amount of heat transferred from the cylinder liner to the cooling water in this portion is larger than in other portions, and the cooling performance in this portion is improved.

In the fifth aspect of the invention, since the turbulent flow generating portion is provided in the region from the midpoint between the cooling water inlet and the cooling water outlet in the cooling water passage to the cooling water outlet, the above region is provided. Due to the turbulent flow of the cooling water generated in step 1, the cooling water having a low temperature and the cooling water having a high temperature are mixed, which prevents the generation of locally high temperature parts in the cooling water. Performance is improved.

Further, in the case of the invention of claim 6, the central portion between the upper dead center side and the lower dead center side in the region from the midpoint between the cooling water inlet and the cooling water outlet in the cooling water passage to the cooling water outlet. Since the cooling water guiding part is provided in the main part, the main flow of the cooling water flowing through the central part is guided toward the top dead center side, and the high temperature of the high temperature flowing through the end part on the top dead center side of the cooling water passage. Since it merges with the cooling water, the temperature rise of the cooling water on the side of the top dead center is suppressed, and the flow rate of the cooling water at this site is increased.
The cooling water retention zone on the top dead center side is also reduced, and the cooling performance on the top dead center side of the latter half portion is improved.

In the seventh aspect of the present invention, in the cooling water passages of the cylinders arranged at the ends in the cylinder row direction, the inter-cylinder side passage is made to flow more cooling water than the anti-cylinder side passage. Since the cooling water passage resistance is provided in the cylinder liner, the cylinder liner has a higher cooling efficiency on the inter-cylinder side, and it is possible to prevent a large temperature difference between the inter-cylinder side and the non-cylinder side.

[0033]

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

In the engine cooling device according to the present invention, the cylindrical cooling water passage formed by the outer wall surface of the cylinder liner and the inner wall surface of the cylinder block is provided independently for each cylinder. The cooling water inflow port and the cooling water outflow port are arranged at positions substantially opposite to each other with respect to the axis of the cylinder.

In the embodiment, in order to make the temperature distribution of the cooling water passage in the circumferential direction of the cylinder liner uniform, from the midpoint between the cooling water inlet and the cooling water outlet of the cooling water passage to the cooling water outlet. This is to improve the cooling performance on the side of the top dead center of the cylinder liner facing the area between them, and the purpose thereof is achieved by the following measures.

(A) The flow velocity of the cooling water on the side of the top dead center is increased and the separation from the cylinder liner is prevented.

(B) To improve the heat dissipation of the cylinder liner on the side of the top dead center.

(C) The cooling performance is improved by generating a turbulent flow in the cooling water on the top dead center side.

(D) The cooling performance is improved by inducing the cooling water flowing through the other portion toward the top dead center side to increase the flow rate.

Each of the above-mentioned measures is the region from the position of about 90 degrees which is the intermediate point between the cooling water inlet and the cooling water outlet to the position of 180 degrees which is the cooling water outlet in the cooling water passage, or the portion facing the region. In particular, it is preferable to take it in the range from the position of about 90 degrees to the position of 150 degrees.

(Embodiment 1) The embodiment 1 is shown in FIG.
As shown in FIG. 2, the cylinder block inner wall surface 4a is located on the top dead center side in the cylinder block inner wall surface 4a in the range of approximately 90 ° position Q to 150 ° position R between the cooling water inlet 2 and the cooling water outlet 3 of the cooling water passage 1. The narrow path portion 8 is formed by providing the bulging portion 7 reaching from 5 to the bottom dead center side 6.

The flow velocity of the cooling water flowing through the narrow passage portion 8 is increased, so that the cooling water flowing through the narrow passage portion 9 becomes approximately 9 mm.
The cooling performance on the top dead center side 5 in the range of 0 degree position Q to 150 degree position R is improved.

Further, the bulging portion 7 has a larger amount of bulging on the bottom dead center side 6 than on the top dead center side 5, so that the top dead center side 5
Since it is possible to increase the amount of cooling water flowing through the other side, the cooling performance on the top dead center side 5 in the above range can be further improved, which is an advantageous configuration.

(Embodiment 2) The embodiment 2 is shown in FIG.
As shown in FIG. 5, a position Q from the cooling water inlet 2 to the cooling water outlet 3 of the cooling water passage 1 is approximately 90 degrees position Q to 150 degrees position R.
The thin-walled portion 10 as a heat radiation portion is provided in the portion of the cylinder liner 9 that faces the range.

The thin portion 10 is provided from the top dead center side to the bottom dead center side of the cylinder liner outer wall surface 9a.
At least the top dead center side is formed to be thin. As a result, the cylinder liner 9 has approximately 9
In the portion of the 0-degree position Q to 150-degree position R on the top dead center side, the heat in the cylinder liner 9 is transferred to the cylinder liner outer wall surface 9a more quickly than in other portions, and is effectively dissipated by the cooling water. Cylinder liner 9 because it can be pressed
The heat dissipation of the above part is improved and the cooling performance is improved.

As a modification of the second embodiment, a high heat transfer portion can be used instead of forming the thin portion 10 as a heat radiating portion for enhancing the heat radiating performance of the above portion of the cylinder liner 9. In this modified example, the heat radiating portion of the cylinder liner 9 is formed by using a material having a higher heat transfer coefficient than the other portions of the cylinder liner 9 only.

The high heat transfer portion in this modification can be provided on the cylinder liner outer wall surface 9a side in place of the base material, or can be embedded in the wall of the cylinder liner 9.

(Third Embodiment) The third embodiment is shown in FIG.
As shown in FIGS. 5A to 5C, positions Q to 15 at approximately 90 degrees between the cooling water inlet 2 and the cooling water outlet 3 in the cooling water passage 1.
In the range of the 0 degree position R, a turbulent flow generation section 12 for generating a turbulent flow 11 in the cooling water flowing through the cooling water passage 1 is provided.

The turbulent flow generating portion 12 projects into the cooling water passage 1 so as to project into the cooling water passage 1 at the top dead center side 5 within the range of approximately 90 ° position Q to 150 ° position R on the cylinder block inner wall surface 4a.
The continuous protrusion 12a is provided near the bottom dead center side and extends from the top dead center side. Therefore, an interval that allows the flow of cooling water is maintained between the continuous protruding portion 12a and the top dead center side 5, and the protruding length of the continuous protruding portion 12a generates an effective turbulent flow in the cooling water. To let
It is preferable that the tip has a length that almost reaches the outer wall surface 9a of the cylinder liner.

Thus, for example, the turbulent flow 11 generated in the cooling water flowing in the cooling water passage 1 by the turbulent flow generating portion 12 composed of the continuous protrusions 12a is the same as the cooling water flowing in the end portion on the top dead center side. Since they interfere with each other to form a vortex flow pattern as shown in the development view of FIG. 5, positions 90 to 15 approximately 90 degrees from the cooling water inlet 2 of the cylinder liner 9 are provided.
The cooling performance on the top dead center side in the range of the 0 degree position R is improved.

6 to 7 show a first modification of the third embodiment, in which the turbulent flow generating section 1 is used.
2 instead of the continuous protruding portion 12a constituting the intermittent protruding portion 12
It was made as b.

The interrupted protrusion 12b in the first modification of the third embodiment is obtained by dividing the continuous protrusion 12a by an appropriate number of notches 12e. As a result, the cooling water flows through each of the plurality of notches 12e in the intermittent protrusion 12b, and the cooling water flowing through the narrow notch 12e serves to make the turbulent flow more complicated.

Therefore, the intermittent protrusion 12b having the notch 12e urges the vortex-like behavior of the cooling water so that the cooling water inflow port 2 of the cylinder liner 9 is in the range of approximately 90-degree position Q to 150-degree position R. Further improve the cooling performance on the top dead center side.

8 to 9 show a second modification of the third embodiment, in which the turbulent flow generating section 1 is used.
Instead of the intermittent protruding portion 12b that extends from the top dead center side to the bottom dead center side, which is included in No. 2, a side by side interrupting protruding portion 12c that extends in the circumferential direction is formed.

In the second modification of the third embodiment, the laterally-interrupted intermittent projecting portions 12c are arranged side by side while the continuous projecting portions 12a are divided by an appropriate number of notches 12e. As a result, the cooling water circulates in each of the plurality of notches 12e even in the intermittent protrusions 12c arranged side by side, and the cooling water that circulates in the narrow notch 12e serves to make the turbulent flow more complicated.

Therefore, the intermittent protrusion 12c having the notch 12e urges the vortex-like behavior of the cooling water, so that the range from the cooling water inflow port 2 of the cylinder liner 9 to the position 90 to the position R of about 90 to 150 degrees. Further improve the cooling performance on the top dead center side.

Further, in the third embodiment, as shown in FIGS. 10 to 11, the continuous protruding portion 12a as the turbulent flow generating portion 12 is used.
Instead of the intermittent projections 12b and 12c, the cooling water passage 1
It is possible to use a third modified example in which the unevenness forming portion 12d provided on at least one of the cylinder block inner wall surface 4a and the cylinder liner outer wall surface 9a that form the is used.

In the third modification of the third embodiment, the turbulent flow is generated in the cooling water passage 1 in the range from the cooling water inflow port 2 to the cooling water outflow port 3 at a position of about 90 degrees Q to 150 degrees R. Concavo-convex forming portion 12d as the portion 12
Is provided on the inner wall surface 4a of the cylinder block and extends from the top dead center side 5 to the bottom dead center side 6.

Therefore, in the third modification of the third embodiment, the above-mentioned approximately 90 degree positions Q to 1 in the cooling water passage 1 are provided.
Since the convex portion and the concave portion extending from the top dead center side 5 to the bottom dead center side 6 are alternately provided only within the range of the 50-degree position R, the cooling water passage 1 flows as a main flow. The flow of the cooling water is disturbed, and further, the cooling water flowing through the end portion on the top dead center side flows countercurrently to generate a turbulent flow 11. Therefore, the eddy current state as shown in the development view of FIG. 11 is widely distributed. It becomes a flow pattern.

As a result, the cooling performance of the cylinder liner 9 on the side of the top dead center from the cooling water inflow port 2 in the range of approximately 90 ° to Q to 150 ° is improved.

In the third modification, the irregularity forming portion 12d as the turbulent flow generating portion 12 has the cylinder block inner wall surface 4a.
However, it goes without saying that the unevenness forming portion 12d may be provided on the outer wall surface 9a of the cylinder liner, or may be provided on both of them.

(Embodiment 4) This embodiment 4 is shown in FIG.
2 to 13, a position Q from the cooling water inflow port 2 to the cooling water outflow port 3 in the cooling water passage 1 is approximately 90 degrees.
Within the range of the 150-degree position R, the main flow of the cooling water flowing through the central portion is directed to the top dead center side 5 at the central portion between the top dead center side 5 and the bottom dead center side 6 of the cooling water passage 1. A cooling water guide portion 13 that guides toward the side is provided.

The cooling water guide portion 13 is provided on the inner wall surface 4a of the cylinder block such that the cooling water guiding portion 13 projects into the cooling water passage 1 and its upper portion is inclined toward the downstream side of the cooling water. Therefore, both between the upper end of the cooling water guide portion 13 and the top dead center side 5 of the cooling water passage 1 and between the lower end of the cooling water guide portion 13 and the lower dead center side 6 of the cooling water passage 1 are both provided. An interval that allows the circulation of cooling water is maintained.

Thus, the cooling water flowing in the central portion of the cooling water passage 1 and near the bottom dead center side is guided toward the top dead center side 5 of the cooling water passage 1 by this cooling water guiding portion 13, and By joining the cooling water flowing through the end portion on the dead center side, the flow rate on the top dead center side in the range of the approximately 90 ° position Q to 150 ° position increases and the flow velocity in this region also improves. Furthermore, by guiding the cooling water toward the top dead center side, it is possible to eliminate the above-described cooling water retention zone.

As a result, the cooling water has a flow pattern which is guided to the top dead center side as shown in the development view of FIG. 13, so that the cooling water inflow port 2 of the cylinder liner 9 is positioned approximately 90 degrees Q-150. The cooling performance on the top dead center side in the range of the degree position R is improved.

Further, as shown in FIGS.
This is a modified example of the fourth embodiment, and instead of the cooling water guide portion 13 provided on the cylinder block inner wall surface 4a so that the upper portion inclines toward the downstream side of the cooling water, it is parallel to the axis of the cylinder liner 9. On the cylinder block inner wall 4
This is the cooling water guide portion 13a provided in a in the axial direction.

Such an axial direction cooling water guiding portion 13a
The modified example in which is used also has the same cooling water guiding function and the function of eliminating the cooling water retention zone as those of the fourth embodiment shown in FIGS.

Further, the use of the cooling water guide portion 13a in this modification provides a great advantage in the casting method of the cylinder block because the cooling water guide portion 3a is oriented in the axial direction of the cylinder liner 9, so that it is industrially advantageous. The above availability is high.

(Embodiment 5) This embodiment is shown in FIG. 16, which shows a one-side bank of a 6-cylinder V-type engine. A water gallery 24 is provided on one side of the bank along the column direction of the cylinders 21 to 23, and an inlet 25 into which cooling water from the water pump flows is opened at one end of the gallery 24.

The cooling water inlet 2 of each cooling water passage 1 of each of the cylinders 21 to 23 is opened to the water gallery 24, and the cooling water inlet 2 and the cooling water outlet 3 intersect with the cylinder row direction (in this example). Are provided so as to substantially face each other in the direction (orthogonal). A swelling portion that swells into the cooling water passage 1 similar to that of the first embodiment is provided at a portion from the top dead center to the bottom dead center of the cylinder block inner wall surface 4a that constitutes the cooling water passage 1. As a result, the narrow path portion 8 is formed.

That is, in each of the cooling water passages 1 of the cylinders 21 and 23 located at both ends of the three cylinders in the cylinder row direction, the cooling water outlet 3 is rotated from the cooling water inlet 2 to the central cylinder 22 side. In the inter-cylinder side path 1a reaching the cooling water outlet 3 from the position of approximately 90 degrees described above.
7a is provided. On the other hand, in the path 1b on the side opposite to the cylinder that goes from the cooling water inlet 2 to the side opposite to the center cylinder 22 and reaches the cooling water outlet 3, the cooling water inlet 2 has a temperature of 50 to 60 degrees. A bulged portion 27b that is relatively long in the circumferential direction from the position to the cooling water outlet 3 is provided.

As described above, the relatively short bulge 27 is formed.
Due to the presence of a and the long bulging portion 27b, the passage resistance of the cooling water flow in the anti-cylinder side passage 1b is larger than that in the inter-cylinder side passage 1a, and the anti-cylinder side passage 1a is opposed to the inter-cylinder side passage 1a. The cooling water is configured to flow more than the inter-cylinder path 1b.

The short bulging portions 27a, 27a are formed in the cooling water passage 1 of the central cylinder 22.
The passage on the side of 1 and the passage on the side of the cylinder 23 are configured so that there is no difference in the flow rate of the cooling water.

Therefore, in the case of the present embodiment, the same operational effect as that of the first embodiment can be obtained, and in the cooling water passages 1 of the cylinders 21 and 23 at both ends, a large amount of cooling water flows between the cylinders, so that the cylinder liner. This is advantageous for cooling the inter-cylinder side portion of No. 9, and it is possible to prevent a temperature difference from occurring between the non-cylinder side portion and the inter-cylinder side portion.

The cooling water passage 1 for the cylinders 21 and 23 is also provided.
16, the cooling water inlet 2 is offsetly arranged at a position 2A (a position displaced by 20 to 30 degrees toward the inter-cylinder side) indicated by a chain line in FIG. 16 so that a large amount of the cooling water flows through the inter-cylinder side. Good. In this case, the ratio of the cooling water flow rate of the inter-cylinder side passage 1a to the cooling water flow rate of the anti-cylinder side passage 1b changes as shown in FIG. 17 depending on the offset amount of the cooling water inlet 2. From this, the effect of the offset can be understood.

FIGS. 18 and 19 show an example of the arrangement of the water gallery 24 as described above as an example of a dry liner. That is, FIG. 18 shows the water gallery 24 arranged at the bottom dead center side, and FIG. 19 shows the gallery 24 arranged at the top dead center side. When the gallery 24 is arranged on the top dead center side, it is advantageous for cooling the cylinder liner 9 on the top dead center side.

(Embodiment 6) This embodiment is a modification of Embodiment 5 and is shown in FIG. 20, in which vertical ribs which serve as passage resistance of the cooling water flow are provided on the inner wall surface of the cylinder block, and the anti-cylinder side path is provided. A larger amount of cooling water is allowed to flow in the inter-cylinder side passage 1a than in 1b.

That is, in each of the passages from the cooling water inlet 2 on both the inter-cylinder side and the inter-cylinder side paths 1a, 1b to the above-mentioned position of about 90 degrees, several lengths are gradually increased. Vertical ribs 31 to 34, 35 to 38 are provided. The vertical ribs 35 to 38 arranged on the anti-cylinder side passage 1b are formed to be longer than the corresponding vertical ribs 31 to 34 on the inter-cylinder side passage 1a.

Therefore, in the case of this example, the anti-cylinder side path 1b
The vertical ribs 35 to 38 of the vertical rib 3 of the inter-cylinder side path 1a.
Since a greater passage resistance is given to the cooling water flow than that of 1-34, the cooling water flows more in the inter-cylinder side passage 1a.

Although not shown, the nuclear path 1
A bulged portion similar to that of the first embodiment is provided between the above-mentioned positions of a and 1b at about 90 degrees to the cooling water outlet 3. This point is the same also in the following Example 7.

(Embodiment 7) This embodiment is a modification of Embodiment 6 and is shown in FIG. 21, in which the vertical ribs 41 to 44 of both the inter-cylinder side and the non-cylinder side paths 1a and 1b are provided. , 45-4
Among the eight, the vertical ribs 41 and 45 arranged at the portion closest to each cooling water inlet 2 are characterized in that the former is formed shorter than the latter.

Therefore, in the case of this example, the anti-cylinder side path 1b
Since the vertical ribs 45 provide greater passage resistance to the cooling water flow than the vertical ribs 41 of the inter-cylinder side passage 1a, more cooling water flows in the inter-cylinder side passage 1a.

[0083]

According to the engine cooling device of the first to sixth aspects, the cooling water inlet and the cooling water outlet of the cooling water passage provided independently for each cylinder are located substantially opposite to each other with respect to the axis of the cylinder. The cooling water passage is provided with a narrow path portion, a turbulent flow generating portion or a cooling water guiding portion in a region from an intermediate point between the cooling water inlet port and the cooling water outlet port to the cooling water outlet port, or a cylinder. Since the heat radiating portion is provided in the portion of the liner facing the above area, insufficient cooling on the top dead center side of the above area is eliminated, so that the temperature distribution in the cylinder liner circumferential direction becomes uniform.
Therefore, thermal deformation of the cylinder liner is prevented, and deterioration of performance due to knocking is prevented.

Further, according to the engine cooling device of the seventh aspect, in the cooling water passages of the cylinders arranged at the end portions in the cylinder row direction, the inter-cylinder side passage is directed toward the inter-cylinder side passage. Since the cooling water passage resistance is provided so that a larger amount of cooling water can flow than that of the cylinder liner, it is possible to prevent a large temperature difference between the inter-cylinder side of the cylinder liner and the anti-cylinder side of the cylinder liner. It is advantageous to prevent the deterioration of

[Brief description of drawings]

FIG. 1 is a plan sectional view of a first embodiment of the present invention.

FIG. 2 is a perspective view of the first embodiment.

FIG. 3 is a plan sectional view of a second embodiment of the present invention.

FIG. 4 is a perspective view of a third embodiment of the present invention.

FIG. 5 is a development view of the third embodiment.

FIG. 6 is a perspective view of a first modification of the third embodiment.

FIG. 7 is a development view of the first modified example.

FIG. 8 is a perspective view of a second modification of the third embodiment.

FIG. 9 is a development view of the second modified example.

FIG. 10 is a plan sectional view of a third modification of the third embodiment.

FIG. 11 is a development view of the third modification.

FIG. 12 is a perspective view of a fourth embodiment of the present invention.

FIG. 13 is a development view of the fourth embodiment.

FIG. 14 is a perspective view of a modified example of the fourth embodiment.

FIG. 15 is a development view of the modified example.

FIG. 16 is a transverse sectional view of a fifth embodiment of the present invention.

FIG. 17 is a graph showing the relationship between the offset angle of the cooling water inlet and the flow rate ratio of the inter-cylinder side path and the anti-cylinder side path.

FIG. 18 is a vertical cross-sectional view showing an example in which a water gallery is arranged on the bottom dead center side.

FIG. 19 is a vertical cross-sectional view showing an example in which a water gallery is arranged on the top dead center side.

FIG. 20 is a perspective view of Embodiment 6 of the present invention.

FIG. 21 is a perspective view of Embodiment 7 of the present invention.

FIG. 22 is a front view illustrating the layout of the engine.

FIG. 23 is a flow pattern of cooling water of a conventional example.

FIG. 24 is a perspective view showing a state of heat transfer in a conventional example.

FIG. 25 is a chart showing changes in typical heat transfer coefficient of a conventional example.

[Explanation of symbols]

 Q 90 degree position R 150 degree position 1 Cooling water passage 1a Inter-cylinder side path 1b Anti-cylinder side path 2 Cooling water inlet 3 Cooling water outlet 4 Cylinder block 4a Cylinder block inner wall surface 5 Top dead center side 6 Bottom dead center side 7 , 27a, 27b Bulging part 8 Narrow path part 9 Cylinder liner 9a Cylinder liner outer wall surface 10 Thin wall part 12 Turbulent flow generating part 13 Cooling water guiding part 21-23 Cylinder 31-38, 41-48 Vertical rib

Claims (7)

[Claims] 1. A cylindrical cooling water passage formed by an outer wall surface of a cylinder liner and an inner wall surface of a cylinder block is independently provided for each cylinder, and a cooling water inlet and a cooling water outlet of the cooling water passage are provided for each cylinder. A narrow passage portion which is provided at positions substantially opposite to each other with respect to the axial center and has a passage width narrower than other portions between the cooling water inlet and the cooling water outlet in the cooling water passage and the cooling water outlet. An engine cooling device characterized by being provided with. 2. The narrow passage portion is formed by a bulging portion provided on the inner wall surface of the cylinder block so as to bulge into the cooling water passage and extending from the top dead center side toward the bottom dead center side. The engine cooling device according to claim 1, wherein the cooling device is an engine cooling device. 3. The engine cooling according to claim 2, wherein the bulging portion is formed so that the bulging amount is larger on the bottom dead center side than on the top dead center side. apparatus. 4. A cylinder-shaped cooling water passage formed by an outer wall surface of a cylinder liner and an inner wall surface of a cylinder block is independently provided for each cylinder, and a cooling water inlet and a cooling water outlet of the cooling water passage are provided for each cylinder. The cylinder liner is provided at positions substantially opposite to each other with respect to the axial center, and in the cylinder liner, a portion of a region from an intermediate point of the cooling water inlet and the cooling water outlet in the cooling water passage to the cooling water outlet is more than a portion other than the other portion. Is a cooling device for an engine, which is provided with a heat radiating portion having high heat radiation. 5. A cylinder-shaped cooling water passage formed by an outer wall surface of the cylinder liner and an inner wall surface of the cylinder block is independently provided for each cylinder, and a cooling water inlet and a cooling water outlet of the cooling water passage are provided in the cylinder. A turbulent flow is provided in the cooling water in the cooling water passage in a region from the intermediate point of the cooling water inlet and the cooling water outlet in the cooling water passage to the cooling water outlet provided at positions substantially opposite to each other with respect to the axis. An engine cooling device, characterized in that a turbulent flow generating portion is provided. 6. A cylindrical cooling water passage formed by an outer wall surface of the cylinder liner and an inner wall surface of the cylinder block is provided independently for each cylinder, and the cooling water inlet and the cooling water outlet of the cooling water passage are provided in the cylinder. Centrally located between the top dead center side and the bottom dead center side in the region from the intermediate point between the cooling water inlet and the cooling water outlet in the cooling water passage to the cooling water outlet provided at positions substantially opposite to each other with respect to the axis. A cooling device for an engine, wherein a cooling water guiding portion for guiding the cooling water flowing through the cooling water passage to the top dead center side is provided in the portion. 7. The cooling water inflow port and the cooling water outflow port of the cooling water passage of the cylinder arranged at the end portion in the cylinder row direction are provided so as to be substantially opposite to each other in the direction intersecting the cylinder row direction. In the cooling water passage, the amount of cooling water flowing in the inter-cylinder side path from the cooling water inlet to the cooling water outlet through between the cooling water inlet and the adjacent cylinder is greater than that from the cooling water inlet to the adjacent cylinder. 7. The passage resistance is provided so as to be larger than the amount of the cooling water flowing in the anti-cylinder side path which goes to the opposite side and reaches the cooling water outlet.
The engine cooling device according to any one of 1.