JP4462246B2 - Cooling structure for multi-cylinder internal combustion engine - Google Patents

Description

The present invention relates to a cooling structure for adjusting cooling around a cylinder by a spacer in the water jacket in a multi-cylinder internal combustion engine including a cylinder block in which a water jacket is formed.

  Conventionally, a reciprocating engine has a cooling structure in which a water jacket is provided around a cylinder in a cylinder block and a cylinder head, and the engine is cooled by cooling water (coolant) flowing through the water jacket. This type of cooling structure takes away heat generated when the engine is driven (combustion) with cooling water, but the required degree of cooling differs depending on the portion of the cylinder outer periphery.

  For example, since the vicinity of the combustion chamber is particularly high at the outer periphery of the cylinder, this portion needs to be cooled more effectively than other portions. On the other hand, if the part far from the combustion chamber is excessively cooled and even the oil that lubricates between the cylinder inner wall surface and the piston ring is cooled, the friction between the piston and the cylinder may increase. For this reason, it is necessary to prevent the part away from the combustion chamber from being excessively cooled.

  Therefore, a spacer has been conventionally used as a member that adjusts the flow rate and flow velocity of the cooling water by changing the cross-section of the flow path in the water jacket in accordance with the degree of cooling required for the portion on the outer periphery of the cylinder.

  As a known document relating to this type of spacer, for example, Patent Document 1 described below can be cited.

  The cylinder block cooling structure disclosed in Patent Document 1 includes a water jacket spacer that is inserted into the water jacket. This spacer is arranged in a state of being spaced a predetermined distance from the inner wall of the water jacket near the cylinder (bore wall surrounding the cylinder). The gaps between these spacers and the bore wall serve as the main flow path for the cooling water. This gap is divided into an upper area, a central area, and a lower area in order from the side closer to the engine head. In the upper area and the lower area, the gap of the spacer is set so as to be larger than the central area. The thickness is different. That is, in the upper region and the lower region where effective cooling is required, the spacer is thinned so that the gap from the bore wall surface to the spacer is increased, and the central region where overcooling is desired to be suppressed is from the bore wall surface to the spacer. The thickness of the spacer is increased so that the gap up to is reduced.

That is, the spacer of Patent Document 1 is formed such that the inner side surface (the surface facing the bore wall surface) is stepped in the axial direction of the cylinder. With such a spacer, it is possible to increase the gap in the upper region and the lower region where the degree of cooling is desired to be high, and to reduce the gap in the central region where the degree of cooling may be low. Thereby, in the cooling structure provided with the spacer of Patent Document 1, an appropriate cooling state corresponding to the required degree of cooling can be realized, and the bore wall average temperature is made uniform in the circumferential direction of the flow of the cooling water. It is supposed to be possible.
JP-A-2005-273469

  By the way, in the case of an engine including a cylinder block in which a plurality of cylinders (cylinders) are arranged in parallel, a cooling water passage such as a drill path may be formed between the cylinders. The inlet and outlet of the cooling water passage are opened in the water jacket. A part of the cooling water flowing through the water jacket enters the cooling water passage from the inlet, exits from the outlet, and returns to the water jacket. The cylinders are cooled by the cooling water flowing through the cooling water passage.

  In such an engine, there is a demand for adjusting the flow direction of the cooling water in order to easily guide a part of the cooling water flowing through the water jacket to the inlet of the cooling water passage.

  Alternatively, in the case of a semi-closed deck type cylinder block, a part of the water jacket opens to the top deck of the cylinder block, while the other part is covered with a bridge. This bridge is formed between both side walls of the water jacket so as to cover the upper portion of the water jacket. If the flow of cooling water in the water jacket is blocked by the presence of this bridge, stagnation is likely to occur on the downstream side of the bridge.

  As described above, the bridge is formed so as to cover the upper portion of the water jacket on the top deck side of the cylinder block. The place where the bridge is formed is located in the vicinity of the combustion chamber, and if the stagnation of the cooling water occurs in this place, the vicinity of the combustion chamber that is desired to be cooled effectively may be difficult to cool. It is considered and a countermeasure is desired.

  On the other hand, the cooling structure of Patent Document 1 described above adjusts the size of the gap (gap) between the bore wall surface and the spacer. According to this, although it is possible to change the flow rate and the flow velocity of the cooling water in each gap, it seems difficult to adjust the direction in which the cooling water flows.

  An object of the present invention is to provide a cooling structure for a multi-cylinder internal combustion engine that can adjust the flow direction of the coolant in the water jacket.

  The cooling structure of the present invention includes a cylinder block in which a plurality of cylinders are arranged in parallel, a water jacket formed in the cylinder block, in which a coolant flows along the cylinder row direction, and the water jacket. And a spacer for cooling a multi-cylinder internal combustion engine. The spacer is formed on the end face on the cylinder head side so as to be inclined or curved with respect to the cylinder row direction from the upstream side to the downstream side of the cooling liquid, and is configured to regulate the flow of the cooling liquid. It has a guidance part.

The cylinder block is a semi-closed deck type in which a bridge is formed to block a part above the water jacket, and the bridge has a side portion facing downstream of the coolant, The coolant extends toward the cylinder head with respect to the cylinder row direction from the upstream to the downstream of the coolant so as to guide the coolant to the side of the side portion .

According to the present invention, the flow of the cooling liquid can be regulated according to the inclination or curved shape of the end face of the spacer, so that a part of the cooling water can be guided in a desired direction .

Further , according to this structure, since the coolant is guided to the side of the side portion of the bridge where the flow of the coolant is obstructed and stagnation is likely to occur, the stagnation of the coolant is suppressed.

  In a preferred embodiment of the present invention, the end face has a concave shape that is inclined in a V shape or curved in a U shape with respect to the cylinder row direction from the upstream to the downstream of the coolant. The surface located downstream is the coolant guiding part.

  According to this structure, the shape of the end surface including the coolant guiding part is simple, and molding is easy.

A cooling structure according to another invention includes a cylinder block in which a plurality of cylinders are arranged in parallel, a water jacket formed in the cylinder block through which coolant flows along the cylinder row direction, and the water jacket arranged in the water jacket. And a cooling structure for a multi-cylinder internal combustion engine. The spacer is formed on the end face on the cylinder head side so as to be inclined or curved with respect to the cylinder row direction from the upstream side to the downstream side of the cooling liquid, and is configured to regulate the flow of the cooling liquid. It has a guidance part. The end surface has a convex shape that is inclined or curved in a mountain shape with respect to the cylinder row direction from upstream to downstream of the coolant, and the surface located downstream of the coolant is the coolant guide portion It has become. A coolant passage is formed between adjacent cylinders of the cylinder block so as to open in the water jacket and allow a part of the coolant to flow therethrough. The cooling liquid guiding portion is configured to guide the cooling liquid to the opening.

According to the present invention, the flow of the cooling liquid can be regulated according to the inclination or curved shape of the end face of the spacer, so that a part of the cooling water can be guided in a desired direction .

Further, according to this structure, the shape of the end surface including the coolant guiding part is simple, and molding is easy .

Further , according to this structure, the cooling liquid is efficiently guided to the cooling passage.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling structure of the multicylinder internal combustion engine which can adjust the direction through which a coolant flows in a water jacket can be provided.

  A cooling structure for a multi-cylinder internal combustion engine according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing a cylinder block 21 of a reciprocating engine 20 to which a cooling structure 10 of the present invention is applied. The engine 20 is an example of a multi-cylinder internal combustion engine referred to in the present invention.

  As shown in FIG. 1, the cylinder block 21 includes four cylinders 22. The cylinders 22 are arranged in series, and are arranged substantially parallel to a crankshaft (not shown), for example. Note that the cylinder row direction in which the cylinders 22 are arranged is B.

  FIG. 2 is a cross-sectional view of the cylinder block 21 shown in FIG. FIG. 2 is a cross-sectional view of the cylinder block 21 showing the cylinder block 21 by cutting the vicinity of each cylinder 22 along the cylinder row direction B. FIG. The engine 20 includes a cylinder head 100, as virtually indicated by a two-dot chain line in FIG. The cylinder head 100 is fixed on the top deck 23 of the cylinder block 21 via a gasket (not shown). Each cylinder 22 opens on a top deck 23 on the cylinder head 100 side of the cylinder block 21.

  A piston 25 is accommodated in each cylinder 22. The piston 25 is connected to a crankshaft (not shown). FIG. 2 shows a state in which the piston 25 is accommodated in one cylinder 22, and the pistons 25 in the other cylinders 22 are omitted.

  As shown in FIG. 1, the cooling structure 10 of the cylinder block 21 includes a cylinder block 21, a water jacket 30 formed in the cylinder block 21, and a spacer 40 disposed in the water jacket 30.

  The water jacket 30 surrounds the four cylinders 22 in the cylinder block 21 and is formed by being dug from the top deck 23 of the cylinder block 21. Cooling water R is fed into the water jacket 30 by a water pump (not shown). The cooling water R is an example of the cooling liquid referred to in the present invention. The coolant R flows in the water jacket 30 in one direction of the cylinder row direction B, and then flows into the cylinder head 100 and exits from the cylinder head 100, for example.

  In the present embodiment, the water jacket 30 is formed so as to pass around each cylinder 22. Therefore, the cooling water R that has entered the water jacket 30 flows around each cylinder 22.

  A plurality of bridges 32 are formed on the top deck 23 of the cylinder block 21 so as to span the width direction of the water jacket 30. A plurality of water holes 31 communicating with the water jacket 30 are formed between the bridges 32. Each bridge 32 covers a part above the water jacket 30. For example, one bridge 32 is provided for each cylinder 22 on each side across the cylinder row direction B. Thus, a cylinder block in which a part of the upper portion of the water jacket is covered with a bridge is generally called a semi-closed deck type (or a semi-open deck type).

  A slit 33 is formed between the cylinders 22 adjacent to each other (this portion is referred to as the adjacent portion 24 in this specification). The slit 33 opens to the top deck 23 side and extends in a direction crossing the cylinder row direction B. The openings 33 a at both ends of the slit 33 are opened in the water jacket 30. The slit 33 is an example of the coolant passage referred to in the present invention.

  The spacer 40 is accommodated in the water jacket 30. FIG. 3 is a perspective view showing a state where the spacer 40 is accommodated in the water jacket 30. In FIG. 3, the spacer 40 accommodated in the water jacket 30 is viewed from the cylinder 22 side.

  The spacer 40 is inserted into the water jacket 30 to adjust the flow path cross-sectional area through which the cooling water R can flow in the water jacket 30 and adjust the direction in which the cooling water R flows. In addition, the spacer 40 in a state before being inserted into the water jacket 30 is indicated by a two-dot chain line on the upper side in FIG. FIG. 4 is a perspective view showing a state in which the spacer 40 is viewed from the side opposite to the direction shown in FIG.

  As shown in FIGS. 3 and 4, the spacer 40 includes a spacer body 41 and a support member 42, and has a curved plate shape as a whole. The spacer body 41 is made of, for example, a sponge material. The support member 42 supports the spacer body 41 in the water jacket 30. The support member 42 includes a main body portion 47 that overlaps the spacer main body 41, a holding portion 47 a that holds the spacer main body 41, and an engagement portion 43 that is hung on the bridge 32 of the cylinder block 21 and supports the spacer 40 in the water jacket 30. And have.

  As shown in FIG. 4, the main body 47 has a size that covers one side surface (surface on the curved outer side) of the spacer main body 41. In a state where the spacer 40 is accommodated in the water jacket 30, the main body portion 47 faces the outside of the water jacket 30. The holding portion 47 a is a claw-like (hook-like) portion formed on the upper edge of the main body portion 47, and is depressed so as to crush a part of the spacer main body 41. The spacer main body 41 is inserted into the main body portion 47. It plays the role of fixing.

  As shown in FIG. 3, the engaging portion 43 includes a first arm portion 46 that extends from the upper edge of the main body portion 47, and a second arm portion 44 that extends horizontally from the tip of the first arm portion 46. have. A distal end 45 (third arm portion) of the second arm portion 44 is bent in a bowl shape on the lower side (main body portion 47 side). In a state where the spacer 40 is accommodated in the water jacket 30, the second arm portion 44 is placed on the bridge 32, and the tip 45 serves to make it difficult for the second arm portion 44 to be detached from the bridge 32. The structure of the support member 42 is not limited to the above structure.

  As described above, since the spacer 40 is supported by the bridge 32, the end surface 48 on the cylinder head 100 side of the spacer main body 41 faces the bridge 32.

  The length of the first arm portion 46 is set such that a predetermined gap S is formed between the top deck 23 of the cylinder block 21 and the end surface 48 of the spacer 40. This point will be specifically described.

  FIG. 5 is a cross-sectional view of the water jacket showing a state in which the spacer 40 accommodated in the water jacket 30 is viewed from the outside of the cylinder 22 toward the inside. In FIG. 5, the support member 42 is indicated by a two-dot chain line. In FIG. 5, the left side is the upstream side through which the cooling water R flows, and the right side is the downstream side through which the cooling water R flows.

  As shown in FIG. 5, the first range 50 on the top deck 23 side on the outer periphery of the cylinder 22 is close to the combustion chamber (not shown), so it is desired to be effectively cooled. Therefore, it is considered that the spacer main body 41 is not located in a portion facing the first range 50 in the water jacket 30. As a result, the spacer 40 does not hinder the flow of the cooling water R flowing on the first range 50.

  Further, when the second range 51 away from the combustion chamber (not shown) on the outer periphery of the cylinder 22 is excessively cooled, the lubricating oil interposed between the piston ring 25a and the inner surface 22a of the cylinder 22 is cooled. End up. When the lubricating oil cools, the friction between the piston ring 25a and the inner surface 22a increases, so it is not preferable that the second range 51 is excessively cooled.

  Therefore, it is considered that the spacer body 41 is disposed at a position facing the second range 51. Since the spacer main body 41 exists in the second range 51, the cooling water R flowing through the second range 51 flows through a gap defined between the spacer main body 41 and the side wall of the water jacket 30. That is, since the spacer main body 41 blocks the flow of the cooling water R, the amount of the cooling water R flowing through the second range 51 is reduced, and the second range 51 is not cooled too much.

  Therefore, the length of the first arm portion 46 is set so that the gap S faces the first range 50 and the spacer body 41 is disposed in a part of the second range 51 in the water jacket 30. Is set to be.

  The spacer body 41 may be disposed so as to contact the side wall of the water jacket 30 in the second range 51. In this case, since the cooling water R does not flow in a part of the second range 51, the outer periphery of the cylinder 22 in the second range 51 is effectively kept warm.

  Here, the end face 48 of the spacer 40 will be specifically described. As clearly shown in FIG. 5, the end surface 48 is formed in a substantially U-shaped valley shape that is curved with respect to the cylinder row direction B and concave with respect to the top deck 23 (that is, the cylinder head 100). Yes. The valley portion 48 a that is most recessed in the end surface 48 is disposed so as to face the bridge 32.

  A portion of the end surface 48 that is located downstream of the valley portion 48a is a coolant guiding portion 48b. The coolant guiding portion 48b is curved so as to rise gently toward the downstream side P of the side portion 32b of the bridge 32 as it goes from upstream to downstream. The upstream portion 48c located upstream of the valley portion 48a in the end surface 48 is gently lowered in a direction away from the bridge 32 from the upstream toward the downstream. The downstream side P of the bridge 32 is the side of the side portion referred to in the present invention. One spacer 40 formed as described above is supported by each bridge 32, for example.

  Next, the operation of the cooling structure 10 will be described.

  As shown in FIG. 5, when the cooling water R reaches the spacer main body 41 of the spacer 40, it flows into the gap S above the end surface 48. The cooling water R flows along the end surface 48 from the upstream side toward the downstream side (indicated by an arrow in the drawing). The gap S is originally narrowed by the presence of the bridge 32. However, the spacer 40 according to the present invention has a substantially U-shaped valley shape so that the gap S is sufficiently secured. The The end face 48 is preferably formed so as to cancel out the amount narrowed by the bridge 32.

  When the trough 48a is exceeded, the cooling water R is guided to the downstream side P of the bridge 32 along the coolant guiding part 48b. The downstream side P of the bridge 32 tends to stagnate by being blocked by the bridge 32. However, the spacer 40 according to the present invention has the coolant guiding portion 48b on the end surface 48, so that the cooling water R is guided to the downstream side P of the bridge 32 along the coolant guiding portion 48b. Thereby, also in the semi-closed deck type cylinder block 21 in which the bridge 32 is formed, the stagnation of the flow on the downstream side P of the bridge 32 is suppressed.

  The cooling water R guided to the downstream side P of the bridge 32 flows in the vicinity of the top deck 23 as it is. Thus, a part of the cooling water R is guided into the slit 33 from the opening 33a formed in the adjacent portion 24 between the cylinders. The cooling water R cools between the cylinders 22 in the process of flowing in the slit 33.

  In the cooling structure 10 configured as described above, the flowing direction of the cooling water R is adjusted by the cooling liquid guiding portion 48 b of the spacer 40. And since the cooling water R is guide | induced to the downstream P by the cooling fluid guidance | induction part 48b, it is suppressed that a stagnation arises with the flow of the cooling water R, As a result, the combustion chamber vicinity is cooled effectively in the outer periphery of the cylinder 22. Is done.

  Further, since the end surface 48 of the spacer 40 has a substantially U-shaped valley shape, the coolant guiding portion 48b that guides the coolant R to the downstream side P can be easily formed.

  Further, the gap S between the end face 48 of the spacer 40 and the bridge 32 of the cylinder block 21 can be made sufficiently wide, and the cooling water R flowing through the first range 50 can be sufficiently secured. 50 can be cooled effectively.

  Next, a cooling structure for a multi-cylinder internal combustion engine according to a second embodiment of the present invention will be described with reference to FIG. In addition, the structure which has a function similar to 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits description. In the present embodiment, the shape of the end surface 48 of the spacer main body 41 on the cylinder head 100 side is different from that of the first embodiment. Other structures may be the same as in the first embodiment.

  The above different points will be specifically described. FIG. 6 is a cross-sectional view of the water jacket 30 showing a state in which the spacer 40 of the present embodiment accommodated in the water jacket 30 is viewed from the outside to the inside of the cylinder 22. In the figure, the support member 42 is indicated by a two-dot chain line.

  As shown in FIG. 6, the end surface 48 of the present embodiment is recessed so as to have a substantially V-shaped valley shape. More specifically, the end surface 48 has a substantially V-shaped valley shape that is inclined with respect to the cylinder row direction B and is concave with respect to the top deck 23 of the cylinder block 21 (that is, the cylinder head 100). In the present embodiment, the same effects as in the first embodiment can be obtained.

  Next, a cooling structure for a multi-cylinder internal combustion engine according to a third embodiment of the present invention will be described with reference to FIGS. In addition, the structure which has a function similar to 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits description. This embodiment is mainly different from the first embodiment in the structure of the spacer 40. Other structures may be the same as those in the first embodiment. The different points will be specifically described.

  FIG. 7 is a plan view showing the top deck 23 on the cylinder head 100 side of the cylinder block 21 of the present embodiment. Unlike the first embodiment, the cylinder block 21 of the present embodiment is a closed deck type. This type of closed deck type cylinder block 21 is such that most of the end face on the cylinder head side is closed, and the interval between adjacent water holes 31 (that is, the width of the bridge 32) is large.

  FIG. 8 is a cross-sectional view of the water jacket 30 showing a state in which the spacer 40 accommodated in the water jacket 30 is viewed from the outside to the inside of the cylinder 22. In the drawing, the engaging portion 43 is indicated by a two-dot chain line. Compared with the first embodiment, the spacer 40 shown in FIG. 9 is greatly different in the engaging portion (the pair of fourth arm portions 49 and the notch portion 102) of the support member 42 to the cylinder block 21. The fourth arm portion 49 extends from both sides of the main body portion 47 across the spacer main body 41 to the top deck 23 side of the cylinder block 21. An end portion 49a of each fourth arm portion 49 is bent outward. Each of the fourth arm portions 49 is generally bowl-shaped (L-shaped).

  On the other hand, the water jacket 30 is formed with a protrusion 101 protruding from the bottom surface (see also FIGS. 8 and 11). In the main body 47 of the spacer 40, a notch 102 that engages with the protrusion 101 is formed at a portion facing the protrusion 101.

  In a state where the spacer 40 is accommodated in the water jacket 30, the fourth arm portion 49 is hooked on the edge 31 b of the water hole 31 of the cylinder block 21, and the notch 102 is engaged with the protrusion 101. As a result, the spacer 40 is fixed in the water jacket 30.

  10 is a cross-sectional view of the water jacket 30 shown along the line F10-F10 shown in FIG. As shown in FIG. 10, a drill path 60 is formed between the cylinders 22. The drill path 60 communicates with the water jackets 30 on both sides of the cylinder 22 crossing the cylinder row direction B, and the openings (inlet 61a and outlet 61b) at both ends of the drill path 60 are opened in the water jacket 30, respectively. The drill path 60 is inclined so as to climb from the inlet 61 a toward the outlet 61 b with respect to the direction crossing the cylinder row direction B, and two drill paths (one example) are formed in one adjacent portion 24. The drill path 60 is an example of a coolant passage referred to in the present invention.

  As shown in FIG. 8, the end surface 48 of the spacer body 41 has a shape protruding in a mountain shape. More specifically, the end surface 48 is inclined with respect to the cylinder row direction B and directed toward the top deck 23 (that is, the cylinder head 100) as it goes from upstream to downstream so as to guide the cooling water R to the inlet 61a of the drill path 60. It has a protruding mountain shape.

  In the present embodiment, the cooling water R is guided to the inlet 61a of the drill path 62 along the cooling liquid guiding portion 48b positioned downstream of the most projecting apex portion 48d on the end face 48, and therefore, between the cylinders 22 adjacent to each other. The (adjacent portion 24) is effectively cooled.

  Moreover, even if the inlet 61a of the drill path 60 is formed at a position away from the top deck 23 of the cylinder block 21 as in the present embodiment, the cooling water R can be efficiently introduced by the end surface 48 having a mountain shape. It can lead to 61a.

  Next, a cooling structure for a multi-cylinder internal combustion engine according to a fourth embodiment of the present invention will be described with reference to FIG. In addition, the structure which has the same function as 3rd Embodiment attaches | subjects the same code | symbol, and abbreviate | omits description. In the present embodiment, the shape of the end surface 48 of the spacer 40 is different from that of the third embodiment. Other structures may be the same as those in the third embodiment. The different points will be specifically described.

  FIG. 11 is a cross-sectional view of the water jacket 30 showing a state in which the spacer 40 accommodated in the water jacket 30 is viewed from the outside of the cylinder 22 toward the inside. In the drawing, the support member 42 is indicated by a two-dot chain line.

  As shown in FIG. 11, the end surface 48 is formed in a smooth convex chevron. More specifically, the end surface 48 has a convex shape that curves toward the cylinder row direction B and protrudes toward the top deck 23 (that is, the cylinder head 100) as it goes from upstream to downstream. In the present embodiment, the same effect as in the third embodiment can be obtained.

  In the third and fourth embodiments described above, the case where the spacer 40 having the end face 48 formed in a mountain shape (convex shape) is applied to a closed deck type cylinder block has been described. Of course, the present invention can be applied to such a semi-closed deck type cylinder block.

The perspective view which shows the cylinder block provided with the multi-cylinder internal combustion engine cooling structure which concerns on the 1st Embodiment of this invention. Sectional drawing which shows the inside of the cylinder block shown by FIG. 1 along the direction in which each cylinder is located in a line. The perspective view which shows the state in which the spacer of the cooling structure of the multicylinder internal combustion engine which concerns on the 1st Embodiment of this invention is accommodated in the water jacket. The perspective view which shows the state which looked at the spacer shown by FIG. 3 from the opposite side to FIG. Sectional drawing of the water jacket which shows the state which looked at the spacer shown in FIG. 3 accommodated in the water jacket from the outer side of a cylinder toward the inner side Sectional drawing of the water jacket which shows the state which looked at the spacer accommodated in the water jacket of the cooling structure of the multicylinder internal combustion engine which concerns on the 2nd Embodiment of this invention toward the inner side from the outer side of the cylinder. The top view which shows the top deck by the side of the cylinder head of a cylinder block provided with the cooling structure of the multicylinder internal combustion engine which concerns on the 3rd Embodiment of this invention. Sectional drawing of the water jacket which shows the state which looked at the spacer accommodated in the water jacket of the cooling structure of the multicylinder internal combustion engine which concerns on the 3rd Embodiment of this invention toward the inner side from the outer side of a cylinder. The front view which looked at the spacer shown by FIG. 8 from the opposite side to FIG. Sectional drawing of the cylinder block shown along F10-F10 line shown by FIG. Sectional drawing of the water jacket which shows the state which looked at the spacer of the cooling structure of the multicylinder internal combustion engine which concerns on the 4th Embodiment of this invention toward the inner side from the outer side of the cylinder.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Cooling structure, 20 ... Engine (multi-cylinder internal combustion engine), 21 ... Cylinder block, 22 ... Cylinder, 30 ... Water jacket, 32 ... Bridge, 32b ... Side part, 33 ... Slit (coolant liquid passage), 40 ... Spacer 48 ... End face on the cylinder head side, 48b ... Cooling liquid guiding part, 60 ... Drill path (cooling liquid passage), 100 ... Cylinder head, B ... Cylinder row direction, P ... Downstream side (side), R ... Cooling water ( Coolant).

Claims (3)

A cylinder block in which a plurality of cylinders are arranged in parallel;
A water jacket that is formed in the cylinder block and in which coolant flows in the cylinder row direction;
A spacer disposed within the water jacket;
A cooling structure for a multi-cylinder internal combustion engine comprising:
The spacer is formed on the end face on the cylinder head side so as to be inclined or curved with respect to the cylinder row direction from the upstream side to the downstream side of the cooling liquid, and is configured to regulate the flow of the cooling liquid. Having a guiding part,
The cylinder block is a semi-closed deck type in which a bridge for closing a part of the water jacket is formed,
The bridge has a side facing downstream of the coolant;
The cooling liquid guide section extends toward the cylinder head with respect to the cylinder row direction as the cooling liquid moves from upstream to downstream so as to guide the cooling liquid to the side of the side section. A cooling structure for a multi-cylinder internal combustion engine.
The end surface has a concave shape inclined in a V shape or curved in a U shape with respect to the cylinder row direction from the upstream side to the downstream side of the coolant, and the surface located downstream of the coolant is 2. The cooling structure for a multi-cylinder internal combustion engine according to claim 1, wherein the cooling structure is a cooling liquid guiding section . A cylinder block in which a plurality of cylinders are arranged in parallel;
A water jacket that is formed in the cylinder block and in which coolant flows in the cylinder row direction;
A spacer disposed within the water jacket;
A cooling structure for a multi-cylinder internal combustion engine comprising:
The spacer is formed on the end face on the cylinder head side so as to be inclined or curved with respect to the cylinder row direction from the upstream side to the downstream side of the cooling liquid, and is configured to regulate the flow of the cooling liquid. Having a guiding part,
The end surface has a convex shape that is inclined or curved in a mountain shape with respect to the cylinder row direction from upstream to downstream of the coolant, and the surface located downstream of the coolant is the coolant guide portion And
Between each cylinder adjacent to the cylinder block, there is formed a coolant passage that opens into the water jacket and through which a part of the coolant flows.
A cooling structure for a multi-cylinder internal combustion engine, wherein the cooling liquid guiding portion is configured to guide the cooling liquid to the opening .

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