JP2011106398A - Cooling structure for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure a smooth cooling water flow while stabilizing the position of a spacer arranged inside the water jacket of a cylinder block. <P>SOLUTION: The spacer 14 arranged inside the water jacket 13 formed to surround the peripheries of a plurality of cylinder bores 12a juxtaposed on the cylinder row line L1 of the cylinder block 11 adjusts the cooling state of the cylinder bores 12a by regulating a flow of cooling water in the intermediate portion of the water jacket 13 in a vertical direction. Since the spacer 14 includes support legs 14i, 14j extending in the vertical direction, the spacer 14 is vertically positioned inside the water jacket 13. Since the support legs 14i, 14j are arranged in a connecting portion 14g which is made to be large in width by facing a portion with the cylinder bores 12a positioned near to each other, an influence on a reduction in the flow passage cross-sectional area of the water jacket 13 caused by providing the support legs 14i, 14j is reduced and the smooth cooling water flow is achieved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  According to the present invention, a spacer is mounted inside a water jacket formed so as to surround a plurality of cylinder bores juxtaposed on a cylinder row of a cylinder block of an internal combustion engine, and the spacer is an intermediate portion in the vertical direction of the water jacket. The present invention relates to a cooling structure for an internal combustion engine including a spacer main body that regulates the cooling state of the cylinder bore by regulating the flow of cooling water in the engine.

  Six spacers for suppressing the flow of cooling water are arranged inside the water jacket surrounding the three cylinder bores arranged in series, and the upper support legs and the lower support legs from the spacer main body of each spacer. Patent Document 1 below discloses that a support leg portion is protruded up and down and the spacer is positioned in the water jacket by the support leg in the vertical direction.

Japanese Patent No. 4149322

  By the way, in the above conventional one, the position where the six spacers are arranged is the position farthest from the cylinder row in the water jacket to the intake side and the exhaust side. The cross-sectional area of the water jacket where the spacer is mounted is reduced by the support legs with respect to the cross-sectional area, and the flow of cooling water around the support legs is obstructed, resulting in a problem that the cooling performance is lowered.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to ensure a smooth flow of cooling water while stabilizing the position of the spacer disposed in the water jacket of the cylinder block.

  To achieve the above object, according to the first aspect of the present invention, a water jacket formed so as to surround a plurality of cylinder bores juxtaposed on a cylinder row line of a cylinder block of an internal combustion engine is provided inside the water jacket. A cooling structure for an internal combustion engine, wherein the spacer includes a spacer body that regulates a cooling state of the cylinder bore by regulating a flow of cooling water in an intermediate portion in the vertical direction of the water jacket. A cooling structure for an internal combustion engine is proposed, comprising a support leg extending in a vertical direction from a main body, wherein the support leg is disposed at a connecting portion of the spacer main body facing a portion where the cylinder bores are connected to each other. .

  According to the invention described in claim 2, in addition to the structure of claim 1, the flow width of the water jacket is larger at the portion where the connecting portion is disposed than at the other portion. A cooling structure for an internal combustion engine is proposed.

  According to a third aspect of the present invention, in addition to the structure of the first or second aspect, the spacer extends in the vertical direction from the spacer main body at one end side in the cylinder row line direction and extends to the water jacket. A cooling structure for an internal combustion engine, comprising: a partition wall that partitions between a cooling water supply port and a cooling water discharge port, wherein the support leg is disposed at the connecting portion on the most other end side in the cylinder row direction. Proposed but proposed.

  The upper support leg 14i and the lower support leg 14j of the embodiment correspond to the support leg of the present invention, and the communication holes 15a and 15b of the embodiment correspond to the cooling water discharge port of the present invention.

  According to the configuration of the first aspect, the spacer mounted inside the water jacket formed so as to surround the plurality of cylinder bores juxtaposed on the cylinder row of the cylinder block is provided in the middle portion in the vertical direction of the water jacket. Regulate the cooling state of the cylinder bore by regulating the flow of cooling water. Since the spacer includes support legs extending in the vertical direction, the spacer can be positioned in the vertical direction inside the water jacket. Since the support legs are provided at the connecting portion of the spacer which is widened by facing the portions where the cylinder bores are close to each other, it is possible to reduce the influence of the reduction in the cross-sectional area of the water jacket due to the provision of the support legs. Smooth flow can be made possible.

  Further, according to the configuration of the second aspect, since the flow path width of the water jacket is larger in the portion where the connecting portion is disposed than in the other portions, the influence on the flow of the cooling water due to the arrangement of the support legs in the connecting portion. Further, it can be kept small.

  Further, according to the configuration of claim 3, the spacer includes a partition wall that extends in the vertical direction from the spacer main body portion at one end side in the cylinder row line direction and partitions the cooling water supply port and the cooling water discharge port of the water jacket. It is possible to prevent the cooling water from being short-circuited from the cooling water supply port to the cooling water discharge port by the partition wall to ensure the cooling performance. At this time, since the support leg is arranged at the connecting portion on the most other end side in the cylinder row line direction, the distance between the partition wall and the support leg can be secured to the maximum, and the spacer can be supported stably. .

The perspective view of one bank of a V type 6 cylinder internal combustion engine. (First embodiment) FIG. 2 is a two-direction arrow view of FIG. 1. (First embodiment) FIG. 3 is a three-direction arrow view of FIG. 1. (First embodiment) FIG. 4 is a four-direction arrow view of FIG. 1. (First embodiment) FIG. 5 is a sectional view taken along line 5-5 of FIG. (First embodiment) FIG. 6 is a sectional view taken along line 6-6 of FIG. (First embodiment) FIG. 7 is a sectional view taken along line 7-7 in FIG. (First embodiment) FIG. (First embodiment) FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 8. (First embodiment) FIG. 10 is a sectional view taken along line 10-10 in FIG. 8; (First embodiment) FIG. 11 is a view taken in the direction of arrow 11 in FIG. 4. (First embodiment) The figure which shows other embodiment of an upper support leg. Position relationship (second embodiment)

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 shows one bank of a cylinder block 11 of a V-type 6-cylinder internal combustion engine. Three cylinder sleeves 12 are embedded in the cylinder block 11 along the cylinder line L1, and a water jacket 13 is formed so as to surround the outer peripheral surface of the cylinder sleeves 12. The cylinder block 11 according to the present embodiment is a siamese type, and the water jacket 13 is not formed between the adjacent cylinder sleeves 12..., So that the water jacket 13 has individual outer peripheral surfaces of the three cylinder sleeves 12. The three cylinder sleeves 12... Are surrounded instead, so that the dimensions of the internal combustion engine in the direction of the cylinder line L1 can be shortened. The water jacket 13 that opens to the deck surface 11a of the cylinder block 11 extends downward from the crankcase side at a certain depth, and the water jacket 13 has an opening of the deck surface 11a of the cylinder block 11 inside the water jacket 13. A synthetic resin spacer 14 inserted from the side is arranged.

  In the present specification, the “vertical direction” is defined as “upper” on the cylinder head side in the cylinder axis L2 direction and “lower” on the crankcase side in the cylinder axis L2 direction.

  As is apparent from FIGS. 1 to 4, the spacer 14 includes a spacer main body 14 a that surrounds most of the outer periphery of the three cylinder sleeves 12 of the cylinder block 11, and a cooling water inlet 14 d that surrounds the remaining portion. And a cooling water outlet 14f. Since the spacer 14 is formed in a closed shape along the water jacket 13 and does not have a cut portion, the rigidity of the spacer 14 is high. The height H0 of the spacer body 14a in the cylinder axis L2 direction is basically constant over the entire circumference. A partition wall 14b that protrudes up and down from between the cooling water inlet portion 14d and the cooling water outlet portion 14f is integrally formed at one end side of the spacer 14 in the cylinder row L1 direction, that is, at the end of the cylinder block 11 on the timing train side. Provided.

  Further, the cooling water inlet portion 14d is a portion adjacent to one side (intake side) of the partition wall 14b and is formed so as to be sandwiched between inlet notches 14c and 14c provided at the upper and lower edges of the spacer 14a. The height H1 of the spacer 14 in the cylinder axis L2 direction is smaller than the height H0 of the spacer body 14a at the cooling water inlet portion 14d. Similarly, the cooling water outlet portion 14f is a portion adjacent to the other side (exhaust side) of the partition wall 14b so as to be sandwiched between outlet notches 14e and 14e provided on the upper and lower edges of the spacer 14. The height H2 of the spacer 14 in the cylinder axis L2 direction is smaller than the height H0 of the spacer main body portion 14a at the cooling water outlet portion 14f. The upper and lower inlet notches 14c and 14c of the cooling water inlet portion 14d are continuous while smoothly curving at the upper and lower edges of the spacer body portion 14a.

  2, 4, and 6, in the vicinity of the portion where the three cylinder bores 12 a are close to each other, the water jacket 13 around each cylinder bore 12 a. The width W ′ (see FIG. 6) of the water jacket 13 in the direction orthogonal to the cylinder row L1 is wider than the width W (see FIGS. 5 and 7) of the water jacket 13 in other portions. Therefore, the thickness T ′ (see FIG. 6) of the connecting portion g... Of the spacer main body portion 14a fitted to the portion where the water jacket 13 intersects at an acute angle is equal to the thickness T (see FIG. 6) of the spacer main body portion 14a in the other portion. 5 and FIG. 7). The width W ′ of the water jacket 13 in the portion that accommodates the connecting portions g... Is further widened at the portion connected to the cylinder head 15, and is radially inward from the upper end of the connecting portions 14 g. Projections 14h are projected in the direction (see FIG. 6).

  Two frustoconical shapes from the two coupling portions 14g and 14g of the spacer body 14a adjacent to the cylinder bore 12a closest to the transmission-side end of the cylinder block 11 and the cylinder bore 12a adjacent to the cylinder bore 12a. Upper support legs 14i and 14i protrude upward, and two truncated cone-shaped lower support legs 14j and 14j protrude downward. The upper ends of the upper support legs 14i and 14i and the upper end of the partition wall 14b are aligned at the same height, and the lower ends of the lower support legs 14j and 14j and the lower end of the partition wall 14b are aligned at the same height.

  Thus, by providing the upper support legs 14i, 14i and the lower support legs 14j, 14j on the connecting parts 14g, 14g having a thickness T 'larger than the thickness T of the other part of the spacer body 14a, The coupling strength of the upper support legs 14i and 14i and the lower support legs 14j and 14j to the spacer main body 14a is increased, and the spacer 14 is firmly supported inside the water jacket 13 by the upper support legs 14i and 14i and the lower support legs 14j and 14j. can do. Further, the positions at which the upper support legs 14i, 14i and the lower support legs 14j, 14j are provided are positions where the flow direction of the cooling water changes inside the water jacket 13 and the flow velocity is lowered. Therefore, the upper support legs 14i, 14i and The influence on the flow of the cooling water due to the provision of the lower support legs 14j, 14j can be reduced.

  As is apparent from FIG. 2, a part of the cooling water of the water jacket 13 of the cylinder block 11 is placed on the lower surface of the cylinder head 15 facing the upper part of the connecting portion 14 g of the spacer 14. The communication holes 15c to be supplied to are opened. And the two upper support legs 14i, 14i provided in the two connecting portions 14g, 14g are arranged slightly deviated downstream of the communication holes 15c, 15c in the flow direction of the cooling water, This makes it easy to supply cooling water to the upper support legs 14i, 14i and supply them to the communication holes 15c, 15c.

  Therefore, when the spacer 14 is mounted inside the water jacket 13, the lower end of the partition wall 14 b contacts the bottom wall of the water jacket 13, and the upper end contacts the lower surface of the gasket 16 sandwiched between the cylinder block 11 and the cylinder head 15. Thus, the end of the spacer 14 on the timing train side is positioned in the vertical direction (see FIG. 9). In addition, the transmission side portion of the spacer 14 is configured such that the lower ends of the lower support legs 14j and 14j are in contact with the bottom wall of the water jacket 13, and the upper ends of the upper support legs 14i and 14i are in contact with the lower surface of the gasket 16, thereby (See FIGS. 4 and 6).

  In the water jacket 13, an upper cooling water passage 13 c is defined between the upper edge of the spacer 14 and the lower surface of the gasket 16, and lower cooling water is provided between the lower edge of the spacer 14 and the bottom of the water jacket 13. A passage 13d is defined. At this time, the height of the upper cooling water passage 13c is determined by the height of the upper support legs 14c and 14c, and the height of the lower cooling water passage 13d is determined by the height of the lower support legs 14j and 14j.

  Hereinafter, the detailed structure of the spacer 14 will be sequentially described.

  As is apparent from FIGS. 4 to 6, the radial thickness T (see FIG. 5) of the spacer body 14 a is constant over the vertical direction and is smaller than the radial width W of the water jacket 13. Is set. When the spacer 14 is mounted inside the water jacket 13, the inner peripheral surface of the spacer main body portion 14a faces the inner wall surface 13a of the water jacket 13 with a slight gap, and therefore the outer peripheral surface of the spacer main body portion 14a. A relatively large gap α is formed between the outer wall surface 13 b of the water jacket 13.

  As is apparent from FIGS. 1 and 3 to 6, a flange-shaped protrusion 14 k is provided to protrude radially outward along the lower edge of the outer peripheral surface of the spacer body 14 a. The outer end in the radial direction of the ridge 14k faces the outer wall surface 13b of the water jacket 13 through a slight gap, so that the spacer main body 14a is positioned in the radial direction at the lower edge where the ridge 14k is formed. Is done. The protrusion 14k is not provided in the lower inlet notch portion 14c and the lower outlet notch portion 14e.

  As is apparent from FIGS. 2 and 8 to 10, a cooling water supply passage 11b extending in parallel with the cylinder row line L1 is formed at the end of the cylinder block 11 on the timing train side. The downstream end communicates with the water jacket 13 via the circular cooling water supply port 11c on the intake side of the spacer 14 with respect to the partition wall 14b. The cooling water supply port 11c of the cylinder block 11 and the cooling water inlet portion 14d of the spacer 14 are provided slightly offset toward the intake side with respect to the cylinder row line L1, so that the cooling water supply parallel to the cylinder row line L1 is provided. The cooling water supplied from the passage 11b can smoothly flow into the water jacket 13 on the intake side without greatly changing the flow direction. Further, as described above, the inlet notches 14c and 14c of the cooling water inlet portion 14d are continuously curved and smoothly curved at the upper edge and the lower edge of the spacer body portion 14a, so that the cooling that has flowed from the cooling water supply port 11c. The water is guided to the inlet notches 14c and 14c of the cooling water inlet portion 14d and is smoothly guided to the upper cooling water passage 13c and the lower cooling water passage 13d.

  The cooling water inlet portion 14d narrowed by being vertically sandwiched between the upper and lower inlet notches 14c and 14c of the spacer 14 has a triangular cross section and protrudes in a wedge shape toward the cooling water supply port 11c. When viewed from the inside of the cooling water supply passage 11b through the cooling water supply port 11c, the ridgeline of the cooling water inlet portion 14d having a triangular cross section of the spacer 14 is exposed (see FIG. 10). The height H1 of the cooling water inlet 14d in the cylinder axis L2 direction is smaller than the height H3 of the cooling water supply port 11c in the cylinder axis L2 direction.

  As apparent from FIGS. 1, 2, 4, 7, and 8, the spacer main body 14 a of the spacer 14 is disposed along the inner wall surface 13 a of the water jacket 13. Only the cooling water outlet portion 14 f sandwiched between the outlet notches 14 e and 14 e protrudes outward in the radial direction, and the portion is arranged along the outer wall surface 13 b of the water jacket 13. Accordingly, a gap β (see FIGS. 2 and 8) is formed between the cooling water outlet 14f of the spacer 14 and the inner wall surface 13a of the water jacket 13. Two communication holes 15 a and 15 b (see FIGS. 2, 4, and 5) that open to the lower surface of the cylinder head 15 face above the cooling water outlet 14 f of the spacer 14.

  As is clear from FIGS. 1, 4 and 8, the outer surface of the partition wall 14b of the spacer 14 has three ribs 14m extending in the vertical direction, and two grooves 14n and 14n sandwiched between them. And are formed. The outer wall surface 13b of the water jacket 13 facing the tips of the three ribs 14m is not a simple arc surface but is bent like a wave (see FIG. 8). A notch 14o is formed at the lower end of the outer surface of the partition wall 14b, and the water jackets 13 on both sides of the partition wall 14b communicate with each other through the notch 14o.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  Before the cylinder head 15 is assembled to the deck surface 11a of the cylinder block 11, the water jacket 13 is opened so as to surround the outer periphery of the cylinder bores 12a of the three cylinder sleeves 12 exposed on the deck surface 11a. A spacer 14 is inserted into the water jacket 13 from the opening. Thereafter, the cylinder head 15 is fastened in a state where the gasket 16 is superimposed on the deck surface 11 a of the cylinder block 11.

  In the assembled state of the spacer 14, the lower end of the partition wall 14b and the lower ends of the lower support legs 14j and 14j are in contact with the bottom surface of the water jacket 13, and the upper end of the partition wall 14b and the upper ends of the upper support legs 14i and 14i are By contacting the lower surface of the gasket 16, the spacer 14 is positioned in the cylinder axis L2 direction. At this time, the inner peripheral surface of the spacer main body portion 14a of the spacer 14 is disposed so as to contact the inner wall surface 13a of the water jacket 13, but since the dimensional accuracy of the inner wall surface 13a of the as-cast water jacket 13 is not high, the spacer In order to prevent 14 from rubbing against the inner wall surface 13a of the water jacket 13 and lowering the assembly performance, a slight gap is formed between the inner peripheral surface of the spacer body 14a and the inner wall surface 13a of the water jacket 13. Is done.

  During operation of the internal combustion engine, cooling water supplied from a water pump (not shown) provided in the cylinder block 11 is supplied from a cooling water supply passage 11b provided at an end of the cylinder block 11 on the timing train side. It flows into the water jacket 13 through 11c. A spacer 14 is arranged inside the water jacket 13, and a narrow cooling water inlet portion 14d sandwiched between the upper and lower inlet notches 14c and 14c faces the spacer 14 facing the cooling water supply port 11c. As is apparent from FIGS. 8 to 10, the height H1 of the cooling water inlet portion 14d in the cylinder axis L2 direction is smaller than the height H3 of the cooling water supply port 11c in the cylinder axis L2 direction, and is triangular. Since the cooling water inlet portion 14d of the cross section protrudes in a wedge shape toward the cooling water supply port 11c, the cooling water that has exited the cooling water supply port 11c is guided by the upper and lower slopes of the cooling water inlet portion 14d in the vertical direction. It can be diverted and smoothly flow into the upper cooling water passage 13c and the lower cooling water passage 13d separated by the spacer 14, and the pressure loss at that time can be minimized.

  In order to further reduce the pressure loss when the cooling water flows into the water jacket 13, the spacer 14 may be divided at that portion by completely notching the cooling water inlet portion 14d. There is a problem that the rigidity of 14 is significantly lowered. On the other hand, according to the present embodiment, the rigidity of the spacer 14 can be ensured while reducing the pressure loss of the cooling water by the cooling water inlet portion 14d in which the height H1 in the vertical direction is reduced.

  Although the cooling water flowing into the upper cooling water passage 13c and the lower cooling water passage 13d of the water jacket 13 tends to branch in the left-right direction, the flow is hindered by the partition wall 14b existing on the right side of the cooling water inlet portion 14d. The direction is changed to the left, and the upper cooling water passage 13c and the lower cooling water passage 13d flow substantially clockwise along the entire length in the clockwise direction. When viewed from the cooling water supply port 11c, the cylinder head extends from the cooling water outlet portion 11f on the opposite side of the partition wall 14b. The 15 communication holes 15a and 15b are discharged. At this time, since the upper cooling water passage 13c and the lower cooling water passage 13d are partitioned by the protrusion 14k provided along the lower edge of the spacer main body 14a, the upper cooling water passage 13c and the lower cooling water passage 13d flow. The cooling water hardly mixes.

  Since the inner peripheral surface of the spacer main body portion 14a of the spacer 14 is in contact with the inner wall surface 13a of the intermediate portion of the water jacket 13 in the cylinder axis L2 direction, the cooling water is less likely to contact the inner wall surface 13a. It is suppressed. As a result, the intermediate portion in the cylinder axis L2 direction of the cylinder bores 12a... Facing the spacer main body portion 14a becomes hotter than the other portions and thermally expands to increase the clearance with the piston. When a large side thrust is applied to the piston during the expansion stroke, it is possible to reduce the friction between the piston and the cylinder bores 12a, thereby contributing to an improvement in fuel consumption of the internal combustion engine. Further, when the intermediate part of the cylinder bores 12a in the cylinder axis L2 direction becomes higher in temperature than the other part, the oil that lubricates the part rises in temperature and the viscosity decreases, so that the effect of reducing friction is further enhanced.

  On the other hand, the upper and lower portions of the cylinder bores 12a in the cylinder axis L2 direction are sufficiently cooled by the cooling water flowing through the upper and lower upper cooling water passages 13c and the lower cooling water passage 13d of the spacer 14, so that they can slide on the cylinder bores 12a. It is possible to prevent the overheating by ensuring the cooling performance of the top and the skirt portion of the piston that is fitted to the top.

  A part of the cooling water flowing into the water jacket 13 from the cooling water supply port 11c of the cylinder block 11 passes between the outer surface of the partition wall 14b of the spacer 14 and the outer wall surface 13b of the water jacket 13 to enter the cooling water inlet. As shown in FIG. 8, the outer surface of the partition wall 14b of the spacer 14 has three ribs 14m... And two grooves 14n and 14n alternately. Therefore, the cooling water that has passed through the gaps on the outer side of the ribs 14m makes a vortex inside the groove 14n, making it difficult to pass through the partition wall 14b. Therefore, even if a gap is formed between the outer surface of the spacer 14 and the outer wall surface 13b of the water jacket 13 in order to ensure the assembling property of the spacer 14, the cooling water supply port 11c and the communication hole 15a, It is possible to effectively prevent short circuit with 15b.

  In addition, since the outer wall surface 13b of the water jacket 13 facing the outer surface of the partition wall 14b of the spacer 14 is curved so as to wave (see FIG. 8), the labyrinth effect is exerted more strongly and the cooling water is further short-circuited. It can be effectively prevented.

  The cooling water that has flowed through the upper cooling water passage 13c and the lower cooling water passage 13d of the water jacket 13 is merged at the cooling water outlet portion 14f of the spacer 14, and is turned upward from there to communicate with the communication holes 15a of the cylinder head 15. After passing through 15b, it is supplied to the water jacket of the cylinder head 15. At this time, the height H2 of the cooling water outlet portion 14f of the spacer 14 in the cylinder axis L2 direction is formed to be smaller than the height H0 of the spacer main body portion 14a in the cylinder axis L2 direction, and the cooling water outlet portion 14f has a diameter. Since the cooling water exiting the lower cooling water passage 13d is arranged so as to be biased outward in the direction and in contact with the outer wall surface 13b of the water jacket 13, the cooling water outlet portion 14f of the spacer 14 and the outer wall surface 13b of the water jacket 13 Is smoothly guided to the communication holes 15a and 15b of the cylinder head 15 through the gap β (see FIGS. 2 and 8). At this time, since the height H2 of the cooling water outlet portion 14f is smaller than the height H0 of the spacer main body portion 14a, the cooling water flowing from the lower cooling water passage 13d toward the communication holes 15a and 15b passes through the cooling water outlet portion 14f. The resistance at the time of passing can be reduced.

  As shown in FIG. 11 (B), even if the protrusion 14k of the spacer 14 is provided along the upper edge of the spacer body 14a, the protrusion 14k partitions the upper cooling water passage 13c and the lower cooling water passage 13d. Although there is no substitute for the effect, a difference occurs in the behavior of the cooling water in the portion where the protrusion 14k is interrupted in the cooling water outlet portion 14f of the spacer 14. That is, as shown in FIG. 11A, when the protrusion 14k of the spacer 14 is provided along the lower edge of the spacer main body 14a as in the present embodiment, the cooling water is supplied from the cooling water outlet 14f. The flow is changed to an upward direction at the portion where the protrusion 14k is interrupted in the horizontal direction until the latest, and is smoothly guided to the communication holes 15a and 15b of the cylinder head 15. Thereby, a sufficient amount of cooling water can be supplied also to the lower cooling water passage 13d below the cooling water outlet portion 14f, and the entire circumference of the cylinder bore 12a facing the cooling water outlet portion 14f can be uniformly cooled.

  On the other hand, as shown in FIG. 11B, if the protrusion 14k of the spacer 14 is provided along the upper edge of the spacer main body 14a, the cooling water is directed upward from a position substantially before the cooling water outlet 14f. Since the flow is changed, there is a problem that a sufficient amount of cooling water does not flow in the lower cooling water passage 13d below the cooling water outlet portion 14f and the cooling performance is lowered.

  In addition, since the notch 14o (refer FIG. 1 and FIG. 9) was provided in the lower end of the partition wall 14b of the spacer 14, a part of cooling water of the lower part of the cooling water inlet part 14d passes through the notch 14o, and cooling water The cooling water that flows into the lower portion of the outlet portion 14f and stays in the cooling water outlet portion 14f is pushed up toward the communication holes 15a and 15b of the cylinder head 15 so that the cooling water is discharged from the water jacket 13. It is performed more smoothly.

  The spacer 14 inserted into the water jacket 13 has a lower end of the partition wall 14b in contact with the bottom wall of the water jacket 13, and an upper end in contact with the lower surface of the gasket 16 sandwiched between the cylinder block 11 and the cylinder head 15. Thus, the end of the spacer 14 on the timing train side is positioned in the vertical direction (see FIG. 9). The lower portion of the lower support legs 14j, 14j is in contact with the bottom wall of the water jacket 13 and the upper end of the upper support legs 14i, 14i is in contact with the lower surface of the gasket 16 so that the transmission side portion of the spacer 14 is in the vertical direction. The partition wall 14b is provided at one end portion in the cylinder row line L1 direction, and the upper support legs 14i and 14i and the lower support legs 14j and 14j are the cylinder bores 12a at the other end portion in the cylinder row line L1 direction. Since the connecting portions 14g and 14g between the second end and the second cylinder bore 12a are provided, the distance from the partition wall 14b to the upper support legs 14i and 14i and the lower support legs 14j and 14j is secured to the maximum. Thus, the support of the spacer 14 can be stabilized.

  Further, by providing the upper support legs 14i, 14i and the lower support legs 14j, 14j on the connecting portions 14g, 14g of the spacer 14, the water jacket 13 is provided by providing the upper support legs 14i, 14i and the lower support legs 14j, 14j. The influence on the flow of cooling water can be minimized.

  The reason is that, in the connecting portions 14g and 14g, the spacer main body portion 14a intersects at an acute angle from two different directions, so the width W ′ (see FIG. 6) of the water jacket 13 in the direction orthogonal to the cylinder row line L1 is The width W of the water jacket 13 in the general part other than the parts 14g and 14g (see FIGS. 5 and 7) is larger. Therefore, by arranging the upper support legs 14i, 14i and the lower support legs 14j, 14j in the portion where the width W ′ of the water jacket 13 is increased, the influence of the water jacket 13 on the cooling water flow is minimized. be able to.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  In the first embodiment, the upper support legs 14i, 14i are formed in a pin shape with a circular cross section, but in the second embodiment, the upper support legs 14i, 14i are plates that curve along the flow of cooling water. Thus, the cooling water flowing through the upper cooling water passage 13c is hardly blocked by the upper support legs 14i and 14i. Further, the upper support legs 14i, 14i are biased to the downstream side in the flow direction of the cooling water from the communication holes 15c, 15c of the cylinder head 15 facing the connection parts 14g, 14g, and the communication holes are the same as in the first embodiment. The cooling water can be smoothly supplied to 15c and 15c. The lower support legs 14j and 14j can be formed in a plate shape like the upper support legs 14i and 14i.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, although the V-type 6-cylinder internal combustion engine is exemplified in the embodiment, the present invention can be applied to an arbitrary type of internal combustion engine having an arbitrary number of cylinders.

  The present invention also relates to an internal combustion engine that bifurcates the coolant supplied from one end side of the cylinder row line L1 into an intake side surface and an exhaust side surface and collects and discharges the coolant at the other end side of the cylinder row line L1. Can be applied.

11 Cylinder block 11c Cooling water supply port 12a Cylinder bore 13 Water jacket 14 Spacer 14a Spacer main body 14b Partition wall 14g Connection part 14i Upper support leg (support leg)
14j Lower support leg (support leg)
15a Communication hole (cooling water outlet)
15b Communication hole (cooling water outlet)
L1 Cylinder row line

Claims (3)

A spacer (14) is mounted inside a water jacket (13) formed so as to surround a plurality of cylinder bores (12a) juxtaposed on a cylinder row line (L1) of a cylinder block (11) of the internal combustion engine. The spacer (14) includes a spacer main body (14a) that regulates the cooling state of the cylinder bore (12a) by regulating the flow of cooling water in the middle portion in the vertical direction of the water jacket (13). In structure
The spacer (14) includes support legs (14i, 14j) extending in the vertical direction from the spacer body (14a), and the support legs (14i, 14j) face the part where the cylinder bores (12a) are close to each other. A cooling structure for an internal combustion engine, wherein the cooling structure is disposed in a connecting portion (14g) of a spacer body (14a).   The cooling structure for an internal combustion engine according to claim 1, wherein a flow path width of the water jacket (13) is larger at a portion where the connecting portion (14g) is disposed than at other portions.   The spacer (14) extends vertically from the spacer main body (14a) on one end side in the direction of the cylinder row (L1) and extends to the cooling water supply port (11c) and the cooling water discharge port ( 15a, 15a) is provided with a partition wall (14b) for partitioning, and the support legs (14i, 14j) are disposed on the connecting portion (14g) on the other end side in the cylinder row line (L1) direction. The cooling structure for an internal combustion engine according to claim 1 or 2.

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