JP2009275575A - Cooling device for internal combustion engine - Google Patents

Abstract

A cooling device for an internal combustion engine capable of reducing pressure loss while sufficiently cooling a portion to be cooled of the internal combustion engine.
A first cooling water passage 10 for applying cooling water to a cylinder block 3 and a cylinder head 4 applied to an internal combustion engine 1 having an exhaust manifold 7 formed integrally with a cylinder head 4 and a cylinder. A second cooling water passage 11 for circulating cooling water is provided on the exhaust side of the head 4 where the exhaust manifold 7 is located. The first cooling water passage 10 includes a block side cooling water passage 12 that extends in the vertical direction inside the cylinder block 3, and a head side cooling water passage that extends from the exhaust side toward the intake side inside the cylinder head 4. 13. The second cooling water passage 11 has a manifold portion cooling water passage 18 which is adjacent to the exhaust manifold 7 and extends in the vertical direction.
[Selection] Figure 1

Description

  The present invention relates to a cooling device applied to an internal combustion engine in which a plurality of cylinders are formed in one direction.

  As a cooling device for an internal combustion engine, a block-side cooling water passage formed inside the cylinder block and a head-side cooling water passage formed inside the cylinder head are provided independently, and the cooling water is circulated through these cooling water passages. There is known one that cools a cylinder block and a cylinder head (see Patent Document 1). In addition, Patent Documents 2 to 4 exist as prior art documents related to the present invention.

JP 2004-324459 A JP 2007-51601 A JP 2004-21645 A Utility Model Registration No. 2526038

  When the apparatus of Patent Document 1 described above is applied to an internal combustion engine in which a plurality of cylinders are formed in one direction, the pressure loss of the cooling water passage and the cooling efficiency of the internal combustion engine vary depending on the arrangement of the cooling water passage. For example, when each cooling water passage is provided so as to extend in the direction in which the cylinders are arranged, the length of the cooling water passage becomes relatively long, so that the pressure loss of the entire cooling water passage increases. In addition, when each cooling water passage is provided so as to extend in a direction orthogonal to the direction in which the cylinders are arranged, the flow passage cross-sectional area of the cooling water passage becomes relatively large, and therefore there is a risk that the cooling of the portion to be cooled will be insufficient. is there.

  Accordingly, an object of the present invention is to provide a cooling device for an internal combustion engine that can reduce pressure loss while sufficiently cooling a portion to be cooled of the internal combustion engine.

  An internal combustion engine cooling apparatus according to the present invention includes a cylinder block in which a plurality of cylinders arranged in one direction are formed, and an intake port for each cylinder on one side in a direction intersecting the arrangement direction of the plurality of cylinders. The exhaust port is applied to an internal combustion engine provided with a cylinder head formed on the other side in the intersecting direction, and a cooling water passage is provided for circulating cooling water to the cylinder block and the cylinder head. A cooling device for an internal combustion engine, wherein the cooling water passage includes a block side cooling water passage extending in the alignment direction inside the cylinder block, and the intake port and the exhaust port inside the cylinder head. The above-described problem is solved by providing a head side cooling water passage extending along each of the above.

  According to the cooling device of the present invention, since the head side cooling water passage extends along the intake port and the exhaust port inside the cylinder head, the passage is provided to extend in the direction in which the cylinders are arranged. Compared to the case, the pressure loss of the entire cooling water passage can be reduced. Further, since the block-side cooling water passage extends in the cylinder arrangement direction inside the cylinder block, the flow passage cross-sectional area is larger than the case where the passage is provided to extend in a direction orthogonal to the cylinder arrangement direction. It becomes small and the flow rate of the cooling water in the block side cooling water passage increases. Therefore, the cylinder block can be sufficiently cooled.

  In one aspect of the present invention, the cooling water passage is provided in the cylinder block, and is provided in a block side cooling water inlet for allowing the cooling water to flow into the block side cooling water passage, and in the cylinder head. A head side cooling water inlet portion that allows cooling water upstream of the cooling water inlet portion to flow into the head side cooling water passage may be further provided. According to this embodiment, the cooling water can be guided to the head side cooling water passage without going through the block side cooling water passage. That is, since the cooling water before being heated by the internal combustion engine flows into each of the block side cooling water passage and the head side cooling water passage, the cylinder block and the cylinder head can be cooled in a well-balanced manner.

  In one embodiment of the present invention, an exhaust manifold that collects exhaust gas led from each cylinder to the exhaust port is formed integrally with the cylinder head, and the cooling water passage is connected to the exhaust manifold inside the cylinder head. You may further provide the manifold part cooling water path which adjoins and extended in the said row direction (Claim 3). According to this aspect, since the manifold portion cooling water passage is provided adjacent to the exhaust manifold whose temperature is relatively high in the cylinder head by collecting the exhaust, the exhaust manifold can be preferentially cooled. it can. Further, since the manifold portion coolant passage extends in the cylinder arrangement direction, the cooling efficiency of the exhaust manifold can be improved as compared with the case where the passage is provided so as to extend in a direction orthogonal to the cylinder arrangement direction.

  In the above aspect, the cooling water passage is provided in the cylinder block, and a block side cooling water inlet for allowing the cooling water to flow into the block side cooling water passage, the block side cooling water passage, and the head side cooling water. A communication passage that communicates with the passage, and a head-side cooling water inlet portion that is provided in the cylinder head and allows the cooling water upstream of the block-side cooling water inlet portion to flow into the manifold portion cooling water passage. (Claim 4). According to this aspect, the cooling water before being heated by the internal combustion engine flows into the manifold portion cooling water passage, so that the cooling efficiency of the exhaust manifold can be further improved.

  As described above, according to the cooling device of the present invention, the head-side cooling water passage extends along the intake port and the exhaust port inside the cylinder head, so that the passage is arranged in the cylinder array. Compared with the case where it is provided so as to extend in the direction, the pressure loss of the entire cooling water passage can be reduced. Further, since the block-side cooling water passage extends in the cylinder arrangement direction inside the cylinder block, the flow passage cross-sectional area is larger than the case where the passage is provided to extend in a direction orthogonal to the cylinder arrangement direction. It becomes small and the flow rate of the cooling water in the block side cooling water passage increases. Therefore, the cylinder block can be sufficiently cooled.

  FIG. 1 shows a main part of an internal combustion engine to which a cooling device according to one embodiment of the present invention is applied. FIG. 2 shows a top view of FIG. As shown in FIGS. 1 and 2, an internal combustion engine (hereinafter sometimes referred to as an engine) 1 includes a cylinder block 3 formed with a plurality of (four in FIG. 2) cylinders 2 arranged in one direction. And a cylinder head 4 disposed at the upper part of the cylinder block 3. The cylinder block 3 and the cylinder head 4 are formed such that the length of the plurality of cylinders 2 in the arrangement direction is larger than the length in the direction orthogonal to the arrangement direction. Hereinafter, the arrangement direction of the plurality of cylinders 2 may be referred to as a vertical direction, and the direction orthogonal to the arrangement direction of the plurality of cylinders 2 may be referred to as a horizontal direction.

  As shown in FIG. 2, the cylinder head 4 has an intake port 5 provided for each cylinder 2 on one side in the horizontal direction (upper side in FIG. 2), and provided for each cylinder 2 on the other side in the horizontal direction. The exhaust ports 6 formed are respectively formed. However, the intake port 5 and the exhaust port 6 may not be in the direction orthogonal to the vertical direction as long as the intake port 5 and the exhaust port 6 are located in a direction crossing the vertical direction. The cylinder head 4 is provided with an exhaust manifold 7 integrally formed on the exhaust side where the exhaust port 6 is located. The exhaust manifold 7 is connected to each exhaust port 6 and has a collecting portion 8 that collects exhaust from each cylinder 2. A cooling device 9 is combined with the engine 1 configured as described above.

  Next, the cooling device 9 will be described with reference to FIGS. 1 and 2. The cooling device 9 includes a first cooling water passage 10 for flowing cooling water to the cylinder block 3 and the cylinder head 4, and a second cooling water passage 11 for flowing cooling water to the exhaust side of the cylinder head 4. Is provided. In each figure, the solid line arrows indicate the first cooling water passage 10 and its cooling water flow, and the broken line arrows indicate the second cooling water passage 11 and its cooling water flow. However, FIG. 2 shows only the flow of cooling water in the cylinder head 4 by arrows. The first cooling water passage 10 extends along the block side cooling water passage 12 extending in the longitudinal direction (longitudinal direction) inside the cylinder block 3 and the intake port 5 and the exhaust port 6 inside the cylinder head 4. A plurality of (four in FIG. 1 and FIG. 2) head-side cooling water passages 13, a first communication passage 14 communicating the block-side cooling water passage 12 and the head-side cooling water passage 13, and a cylinder head And a discharge passage 15 extending in the vertical direction on the intake side where the four intake ports 5 are located. The head side cooling water passage 13 is connected to the discharge passage 15. The first communication passage 14 is connected to the block-side cooling water passage 12 on the exhaust side of the cylinder block 3, and is connected to the head-side cooling water passage 13 on the exhaust side of the cylinder head 4.

  As shown in FIG. 1, the first cooling water passage 10 includes a block-side cooling water inlet portion 16 provided on the exhaust-side wall surface of the cylinder block 3 and a cooling water provided on the intake-side wall surface of the cylinder head 4. And an outlet portion 17. The block-side cooling water inlet 16 is located at the end of one side in the vertical direction (the right side in FIG. 1) so as to communicate with the block-side cooling water passage 12. The cooling water outlet portion 17 is located at the end of the other side in the longitudinal direction so as to communicate with the discharge passage 15.

  As shown in FIG. 2, the second cooling water passage 11 communicates with the manifold portion cooling water passage 18 adjacent to the exhaust manifold 7 of the cylinder head 4 and extending in the alignment direction, and the manifold portion cooling water passage 18. And a head-side cooling water inlet portion 19 provided on one end face of the cylinder head 4 in the longitudinal direction. The manifold portion cooling water passage 18 is formed to be somewhat longer than the collecting portion 8 of the exhaust manifold 7, bends to the exhaust side at the opposite end of the head side cooling water inlet portion 19, and enters the discharge passage 15. Connected. Further, the manifold portion coolant passage 18 and the first communication passage 14 are connected by a second communication passage 20.

  Next, with reference to FIG.1 and FIG.2, the flow of the cooling water which distribute | circulates the 1st cooling water channel | path 10 is demonstrated. The cooling water sent from the pump (not shown) to the block side cooling water inlet 16 is guided to the first communication passages 14 while flowing in the block side cooling water passage 12 in the vertical direction (left side in FIG. 1). The cooling water guided to the first communication path 14 flows in the first communication path 14 in the direction toward the cylinder head 4 and is guided to the head side cooling water path 13. The cooling water guided to the head side cooling water passage 13 flows in the head side cooling water passage 13 in the direction from the exhaust side to the intake side of the cylinder head 4 and flows into the discharge path 15. The cooling water guided to the discharge passage 15 is guided in the vertical direction (left side in FIG. 1) while joining with the cooling water flowing in from each head side cooling water passage 13, and from the cooling water outlet portion 17 to the outside of the cylinder head 4. To be discharged.

  Next, the flow of cooling water flowing through the second cooling water passage 11 will be described. The pump described above sends cooling water to the block side cooling water inlet portion 16 and also to the head side cooling water inlet portion 19. That is, the cooling water upstream of the block side cooling water inlet 16 is guided to the head side cooling water inlet 19. The head side cooling water inlet portion 19 allows the cooling water to flow into the manifold portion cooling water passage 18. The cooling water guided to the manifold portion cooling water passage 18 flows in the vertical direction (left side in FIG. 2) while joining the cooling water via the first communication passage 14 and the second communication passage 20, and then the discharge passage 15. Led to. The cooling water guided to the discharge path 15 merges with the cooling water via the first cooling water passage 10 and is discharged from the cooling water outlet portion 17 to the outside of the cylinder head 4.

  In the first cooling water passage 10 described above, since the head side cooling water passage 13 extends along each of the intake port 5 and the exhaust port 6, the head side cooling water passage 13 is provided to extend in the vertical direction. Compared to the case, the pressure loss in the first cooling water passage 10 is reduced. Therefore, the pump can be reduced in size. Further, since the block-side cooling water passage 12 extends in the vertical direction, the flow passage cross-sectional area becomes smaller than that in the case where the block-side cooling water passage 12 is provided so as to extend in the horizontal direction, and the block-side cooling water The flow rate of the cooling water in the passage 12 increases. Therefore, the cylinder block 3 can be sufficiently cooled.

  In the cooling device 9 of the present embodiment, the manifold portion cooling water passage 18 is provided so as to be adjacent to the exhaust manifold 7, so that the exhaust manifold 7 is preferentially cooled by the cooling water flowing through the manifold portion cooling water passage 18. be able to. Further, since the manifold portion cooling water passage 18 extends in the vertical direction, the cooling efficiency of the exhaust manifold 7 is improved as compared with the case where the manifold portion cooling water passage 18 is provided so as to extend in the horizontal direction. In addition, since the cooling water upstream of the block-side cooling water inlet portion 16 is guided to the head-side cooling water inlet portion 19, the cooling water before the temperature rises in the internal combustion engine 1 enters the manifold portion cooling water passage 18. Inflow. Thereby, the cooling efficiency of the exhaust manifold 7 is further improved.

  In the first cooling water passage 10 of this embodiment, the block-side cooling water passage 12 and the head-side cooling water passage 11 are communicated with each other through the first communication passage 14, but the first communication passage 14 is omitted. The block-side cooling water passage 12 and the head-side cooling water passage 13 may be provided independently inside the internal combustion engine 1. In this case, with respect to the block side cooling water passage 12, a block side cooling water outlet portion (not shown) is added to the cylinder block 3 so as to communicate with the block side cooling water passage 12, and a block side cooling water inlet portion is provided. What is necessary is just to comprise so that cooling water may distribute | circulate in the path | route of 16-> block side cooling water channel | path 12-> block side cooling water exit part. On the other hand, the head-side cooling water passage 13 may be configured such that the cooling water flows through the path of the head-side cooling water inlet portion 19 → the head-side cooling water passage 13 → the discharge passage 15 → the cooling water outlet portion 17. Thereby, the cooling water before the temperature rises in the internal combustion engine 1 flows into the block side cooling water passage 12 and the head side cooling water passage 13, respectively, so that the cylinder block 3 and the cylinder head 4 are cooled with good balance. Can do.

  The present invention is not limited to the above-described embodiment, and can be implemented in various forms. For example, the first cooling water passage 10 may be configured such that the cooling water flows in the head side cooling water passage 13 in a direction from the intake side to the exhaust side of the cylinder head 4. The exhaust manifold 7 is not limited to being provided integrally with the cylinder head 4, and may be provided integrally with the cylinder block 3, for example, or may be provided somewhat apart from the cylinder block 3 and the cylinder head 4. The second cooling water passage 11 is not limited to the above-described example, and can be appropriately changed as long as the exhaust manifold 7 can be cooled. For example, when the exhaust manifold 7 can be sufficiently cooled only by the cooling water flowing into the manifold portion cooling water passage 18 from the second cooling water passage 20, the head side cooling water inlet portion 19 may be omitted. .

The figure which showed the principal part of the internal combustion engine to which the cooling device of this invention was applied. The top view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Cylinder 3 Cylinder block 4 Cylinder head 5 Intake port 6 Exhaust port 7 Exhaust manifold 9 Cooling device 10 1st cooling water path (cooling water path)
11 Second cooling water passage (cooling water passage)
12 Block side cooling water passage 13 Head side cooling water passage 14 First communication passage (communication passage)
16 Block side cooling water inlet portion 17 Cooling water outlet portion 18 Manifold portion cooling water passage 19 Head side cooling water inlet portion 20 Second communication passage

Claims (4)

A cylinder block in which a plurality of cylinders arranged in one direction are formed; one side in a direction in which an intake port for each cylinder intersects the arrangement direction of the plurality of cylinders; and the other in a direction in which an exhaust port for each cylinder intersects Applied to an internal combustion engine having a cylinder head formed on each side of
A cooling device for an internal combustion engine provided with a cooling water passage for circulating cooling water to the cylinder block and the cylinder head,
The cooling water passage includes a block side cooling water passage extending in the alignment direction inside the cylinder block, and a head side extending along the intake port and the exhaust port inside the cylinder head. A cooling device for an internal combustion engine, comprising a cooling water passage.   The cooling water passage is provided in the cylinder block, and a block-side cooling water inlet portion for allowing cooling water to flow into the block-side cooling water passage, and provided in the cylinder head, upstream of the block-side cooling water inlet portion. The cooling device for an internal combustion engine according to claim 1, further comprising a head side cooling water inlet that allows the side cooling water to flow into the head side cooling water passage. An exhaust manifold that collects exhaust led from each cylinder to the exhaust port is formed integrally with the cylinder head,
2. The cooling device for an internal combustion engine according to claim 1, wherein the cooling water passage further includes a manifold portion cooling water passage that is adjacent to the exhaust manifold inside the cylinder head and extends in the arrangement direction.   The cooling water passage is provided in the cylinder block, and communicates a block side cooling water inlet for allowing cooling water to flow into the block side cooling water passage, and the block side cooling water passage and the head side cooling water passage. 4. The apparatus according to claim 3, further comprising: a communication path; and a head side cooling water inlet portion provided in the cylinder head and configured to allow cooling water upstream of the block side cooling water inlet portion to flow into the manifold portion cooling water passage. A cooling apparatus for an internal combustion engine as described.

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