JP6985679B2 - Multi-cylinder engine cooling structure - Google Patents

Description

The present invention belongs to the technical field relating to the cooling structure of a multi-cylinder engine.

Conventionally, as a cooling structure for a multi-cylinder engine, a water jacket is formed on the cylinder block so as to surround the periphery of a plurality of cylinder bores (multiple cylinder bore walls), and the coolant pumped from the water pump is introduced into the water jacket. The structure that cools the engine is known.

Further, for the purpose of improving cooling performance and the like, as disclosed in Patent Document 1, for example, it is known that a water jacket spacer for partitioning an internal space of the water jacket is housed in the water jacket. The water jacket spacer of Patent Document 1 is formed with a plurality of introduction holes communicating the outer portion and the inner portion of the water jacket spacer in the water jacket at positions corresponding to the adjacent cylinder bores. Then, the coolant pumped from the water pump first flows into the outer portion of the water jacket, and a part of the coolant flows into the inner portion by passing through the introduction hole. There is. With such a configuration, the portion between the cylinder bores of the cylinder block (cylinder bore wall), which tends to be hot, is effectively cooled.

JP-A-2015-224627

By the way, in a compression ignition type engine such as a diesel engine, in order to secure an environment for stable compression ignition of fuel, that is, to maintain the temperature of the combustion chamber of the engine at a temperature capable of compression ignition. It is necessary to keep the combustion chamber warm. On the other hand, it is necessary to cool the combustion chamber of the engine, especially during high load operation.

Therefore, as in Patent Document 1, the water jacket spacer forms an inner flow path located inside the water jacket spacer and an outer flow path located outside the water jacket spacer in the water jacket. It is conceivable to form a communication hole in the water jacket spacer for communicating the inner flow path and the outer flow path. Then, the cooling liquid pressure-fed from the water pump is made to flow into the outer flow path, and a part of the cooling liquid is made to flow into the inner flow path by passing through the introduction hole. In this case, in the inner flow path, the fresh coolant passing through the communication hole keeps the combustion chamber warm so that the fresh coolant does not spread over the entire inner flow path, and the vicinity of the cylinder bores on the cylinder bore wall is reached. It is conceivable to cool it.

However, simply forming a communication hole in the water jacket spacer does not stabilize the flow of the coolant that has passed through the communication hole, and depending on the flow, fresh coolant spreads over the entire inner flow path and the combustion chamber. It becomes difficult to secure the heat retention performance.

The present invention has been made in view of these points, and an object of the present invention is to cool a multi-cylinder engine capable of ensuring both cooling performance of a combustion chamber and heat retaining performance. To provide the structure.

In order to achieve the above object, in the present invention, a cylinder block is provided with a plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores, and a cylinder head is attached to one surface in the axial direction of the cylinder bores. The water jacket spacer is provided by the peripheral wall portion for a cooling structure of a multi-cylinder engine including a water jacket spacer housed in a water jacket of the cylinder block and having a peripheral wall portion surrounding the periphery of the plurality of cylinder bores. An inner flow path located inside the peripheral wall portion and an outer flow path located outside the peripheral wall portion are formed in the water jacket, and the outer surface of the cylinder block is covered with the outer flow path. A coolant inlet to the outer flow path is provided to communicate with the outer flow path, and the peripheral wall portion communicates with the inner flow path and the outer flow path at a position corresponding to the adjacent cylinder bores. A cooling liquid having a hole formed therein and flowing into the inner flow path from the outer flow path through the communication hole on the anti-cylinder head side portion of the communication hole on the inner flow path side surface of the peripheral wall portion. A projecting portion is provided on the inner flow path so that at least a part of the cylinder head can easily flow to the cylinder head side, and the communication hole is formed in the vicinity of the end portion of the peripheral wall portion on the cylinder head side. The protrusion is formed so that the surface of the protrusion on the cylinder head side is continuous with the portion of the inner peripheral surface of the communication hole on the anti-cylinder head side .

With the above configuration, the coolant flows into the outer flow path from the coolant inlet, and a part of the coolant flows into the inner flow path through the communication hole. The coolant that has flowed into the inner flow path easily flows toward the portion between the adjacent cylinder bores (constricted portion) of the cylinder bore wall along the surface of the protruding portion on the cylinder head side, and easily hits the constricted portion of the cylinder bore wall. Become. Moreover, since at least a part of the coolant that has flowed into the inner flow path through the communication hole is easily flowed to the cylinder head side by the protruding portion, basically, after hitting the constricted portion of the cylinder bore wall, It will flow to the cylinder head side, and the coolant flowing to the cylinder head side will be able to cool the portion of the constricted portion of the cylinder bore wall, which is particularly hot, on the cylinder head side.

Further, of the cooling liquid flowing into the inner flow path through the communication hole, the amount of the cooling liquid flowing to the anti-cylinder head side is reduced by the protruding portion, so that the cooling liquid in the inner flow path is opposite to the protruding portion. On the cylinder head side, it is difficult for fresh coolant to flow, and the coolant is stagnant. As a result, the heat retention performance of the combustion chamber of the multi-cylinder engine can be ensured.

Therefore, it is possible to effectively cool the cylinder head side of the constricted part of the cylinder bore wall to ensure the cooling performance of the combustion chamber of the multi-cylinder engine, and to maintain the heat retention performance of the combustion chamber by the coolant in the inner flow path. Can be secured .

Further, since the surface of the protruding portion on the cylinder head side is continuous with the portion on the inner peripheral surface of the communication hole on the anti-cylinder head side, the coolant flowing into the inner flow path through the communication hole flows into the cylinder bore wall. It becomes easier to flow toward the constricted part. Further, since the communication hole is formed in the vicinity of the end portion on the cylinder head side of the peripheral wall portion, the end portion on the cylinder head side and its vicinity, which are particularly hot, among the constricted portions of the cylinder bore wall, are effectively cooled. You will be able to. In addition, the coolant can be stored in a stagnant state in the part of the inner flow path other than the end on the cylinder head side, and as a result, it is easier to secure the heat retention performance of the combustion chamber of the multi-cylinder engine. Become.

In the cooling structure of the multi-cylinder engine, it is preferable that the surface of the protruding portion on the cylinder head side is inclined so as to be located closer to the cylinder head side toward the protruding tip side.

As a result, the coolant that has flowed into the inner flow path through the communication hole becomes easier to flow toward the cylinder head side due to the protruding portion. Therefore, it becomes easier to secure both the cooling performance and the heat retaining performance of the combustion chamber of the multi-cylinder engine.

In the cooling structure of the multi-cylinder engine, the water jacket spacer is made of resin, and at least the portion on the protruding tip side of the protruding portion is due to the remaining gate portion left by cutting the gate during molding of the water jacket spacer. It is preferably formed.

As a result, the protrusion can be easily and efficiently formed as compared with the case where the protrusion is formed separately from the gate, and it is not necessary to reduce the remaining amount of the gate. Therefore, the water jacket spacer can be easily manufactured.

In order to achieve the above object, another invention includes a cylinder block in which a plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores are provided, and a cylinder head is attached to one surface in the axial direction of the cylinder bores. The water jacket spacer is intended for a cooling structure of a multi-cylinder engine including a water jacket spacer housed in a water jacket of the cylinder block and having a peripheral wall portion surrounding the periphery of the plurality of cylinder bores. Therefore, an inner flow path located inside the peripheral wall portion and an outer flow path located outside the peripheral wall portion are formed in the water jacket, and the cylinder block is provided with the outer flow path. A coolant inlet to the outer flow path is provided to communicate with the flow path, and the peripheral wall portion has a communication hole for communicating the inner flow path and the outer flow path at a position corresponding to the space between adjacent cylinder bores. Is formed, and on the surface of the peripheral wall portion on the inner flow path side, the coolant flowing into the inner flow path from the outer flow path through the communication hole at the portion on the anti-cylinder head side of the communication hole. A protruding portion is provided on the inner flow path to facilitate the flow of at least a part to the cylinder head side, and the surface of the protruding portion on the cylinder head side is located closer to the cylinder head side toward the protruding tip side. It was configured to be tilted like this.

With the above configuration, the coolant flows into the outer flow path from the coolant inlet, and a part of the coolant flows into the inner flow path through the communication hole. The coolant that has flowed into the inner flow path easily flows toward the portion between the adjacent cylinder bores (constricted portion) of the cylinder bore wall along the surface of the protruding portion on the cylinder head side, and easily hits the constricted portion of the cylinder bore wall. Become. Moreover, since at least a part of the coolant that has flowed into the inner flow path through the communication hole is easily flowed to the cylinder head side by the protruding portion, basically, after hitting the constricted portion of the cylinder bore wall, It will flow to the cylinder head side, and the coolant flowing to the cylinder head side will be able to cool the portion of the constricted portion of the cylinder bore wall, which is particularly hot, on the cylinder head side.

Further, of the cooling liquid flowing into the inner flow path through the communication hole, the amount of the cooling liquid flowing to the anti-cylinder head side is reduced by the protruding portion, so that the cooling liquid in the inner flow path is opposite to the protruding portion. On the cylinder head side, it is difficult for fresh coolant to flow, and the coolant is stagnant. As a result, the heat retention performance of the combustion chamber of the multi-cylinder engine can be ensured.

Therefore, it is possible to effectively cool the cylinder head side of the constricted part of the cylinder bore wall to ensure the cooling performance of the combustion chamber of the multi-cylinder engine, and to maintain the heat retention performance of the combustion chamber by the coolant in the inner flow path. Can be secured.

Further, with the above configuration, the coolant flowing into the inner flow path through the communication hole becomes easier to flow to the cylinder head side by the protruding portion. Therefore, it becomes easier to secure both the cooling performance and the heat retaining performance of the combustion chamber of the multi-cylinder engine.

In the cooling structure of the multi-cylinder engine, the water jacket spacer is made of resin, and at least the portion on the protruding tip side of the protruding portion is due to the remaining gate portion left by cutting the gate during molding of the water jacket spacer. It is preferably formed.

As a result, the protrusion can be easily and efficiently formed as compared with the case where the protrusion is formed separately from the gate, and it is not necessary to reduce the remaining amount of the gate. Therefore, the water jacket spacer can be easily manufactured.

In order to achieve the above object, in another invention, a cylinder block is provided with a plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores, and a cylinder head is attached to one surface in the axial direction of the cylinder bores. The water jacket spacer is intended for a cooling structure of a multi-cylinder engine including a water jacket spacer housed in a water jacket of the cylinder block and having a peripheral wall portion surrounding the periphery of the plurality of cylinder bores. The portion is configured to form an inner flow path located inside the peripheral wall portion and an outer flow path located outside the peripheral wall portion in the water jacket, and the cylinder block has the above-mentioned cylinder block. A coolant inlet to the outer flow path is provided to communicate with the outer flow path, and the peripheral wall portion communicates with the inner flow path and the outer flow path at a position corresponding to the adjacent cylinder bores. A cooling liquid having a hole formed therein and flowing into the inner flow path from the outer flow path through the communication hole on the anti-cylinder head side portion of the communication hole on the inner flow path side surface of the peripheral wall portion. A protruding portion is provided on the inner flow path so that at least a part of the water can easily flow to the cylinder head side. The water jacket spacer is made of resin and is at least on the protruding tip side of the protruding portion. The portion is formed by the remaining part of the gate left by cutting the gate at the time of molding the water jacket spacer.

With the above configuration, the coolant flows into the outer flow path from the coolant inlet, and a part of the coolant flows into the inner flow path through the communication hole. The coolant that has flowed into the inner flow path easily flows toward the portion between the adjacent cylinder bores (constricted portion) of the cylinder bore wall along the surface of the protruding portion on the cylinder head side, and easily hits the constricted portion of the cylinder bore wall. Become. Moreover, since at least a part of the coolant that has flowed into the inner flow path through the communication hole is easily flowed to the cylinder head side by the protruding portion, basically, after hitting the constricted portion of the cylinder bore wall, It will flow to the cylinder head side, and the coolant flowing to the cylinder head side will be able to cool the portion of the constricted portion of the cylinder bore wall, which is particularly hot, on the cylinder head side.

Further, of the cooling liquid flowing into the inner flow path through the communication hole, the amount of the cooling liquid flowing to the anti-cylinder head side is reduced by the protruding portion, so that the cooling liquid in the inner flow path is opposite to the protruding portion. On the cylinder head side, it is difficult for fresh coolant to flow, and the coolant is stagnant. As a result, the heat retention performance of the combustion chamber of the multi-cylinder engine can be ensured.

Therefore, it is possible to effectively cool the cylinder head side of the constricted part of the cylinder bore wall to ensure the cooling performance of the combustion chamber of the multi-cylinder engine, and to maintain the heat retention performance of the combustion chamber by the coolant in the inner flow path. Can be secured.

Further, with the above configuration, the protruding portion can be formed easily and efficiently as compared with the case where the protruding portion is formed separately from the gate, and it is not necessary to reduce the remaining amount of the gate. Therefore, the water jacket spacer can be easily manufactured.

In one embodiment of the cooling structure of the multi-cylinder engine, the inner side wall surface of the water jacket is driven into a portion on the cylinder head side between adjacent cylinder bores and recessed inside the wall rather than the portion on the anti-cylinder head side. The protrusion is provided on the inner flow path side surface of the peripheral wall portion so that the tip portion of the protrusion enters the drive-in portion.

That is, when the inner side wall surface (outer side surface of the cylinder bore wall) of the water jacket does not have a driving portion, it is opposite to the protruding portion on the peripheral wall portion of the water jacket spacer at the position corresponding to the adjacent cylinder bores. The gap between the cylinder head side portion and the inner side wall surface of the water jacket is increased by the amount of protrusion of the protrusion. On the other hand, when the inner side wall surface of the water jacket has a driving portion, the portion on the side opposite to the cylinder head side from the protruding portion on the peripheral wall portion of the water jacket spacer and the inner side wall surface of the water jacket. The gap between the driven portion and the portion on the side opposite to the cylinder head can be reduced regardless of the amount of protrusion of the protruding portion. Therefore, it is possible to prevent the amount of the coolant in the inner flow path from becoming unnecessarily large.

Further, even if the error of the protrusion amount of the protrusion is large, the protrusion can be prevented from interfering with the inner side wall surface of the water jacket, and as a result, the water jacket spacer can be easily manufactured.

As described above, according to the cooling structure of the multi-cylinder engine of the present invention, in the peripheral wall portion of the water jacket spacer housed in the water jacket of the cylinder block of the multi-cylinder engine, at the position corresponding to the space between the adjacent cylinder bores. A communication hole is formed to communicate the inner flow path located inside the peripheral wall portion and the outer flow path located outside the peripheral wall portion, and the anti-cylinder head side of the communication hole is formed on the surface of the peripheral wall portion on the inner flow path side. The portion is provided with a protruding portion protruding from the inner flow path so that at least a part of the coolant flowing from the outer flow path through the communication hole into the inner flow path can easily flow to the cylinder head side. As a result, it becomes possible to secure both the cooling performance and the heat retaining performance of the combustion chamber of the multi-cylinder engine.

It is a perspective view which shows the cylinder block of the multi-cylinder engine to which the cooling structure which concerns on embodiment of this invention is applied, in the state which accommodates the water jacket spacer in the block water jacket. FIG. 1 is a plan view of a cylinder block in which a water jacket spacer is housed in a block water jacket. It is sectional drawing which cut along the line III-III of FIG. It is a perspective view which shows the water jacket spacer. It is the figure which looked at the water jacket spacer from the anti-transmission side. It is the figure which looked at the water jacket spacer from the exhaust side. It is the figure which looked at the water jacket spacer from the transmission side. It is the figure which looked at the water jacket spacer from the intake side. It is an enlarged plan view which shows the constricted part of a cylinder bore wall and the inner curved part of a block water jacket in an enlarged manner. FIG. 2 is a cross-sectional view taken along the line XX of FIG. FIG. 3 is an enlarged cross-sectional view showing an enlarged portion of the XI portion of FIG. It is a perspective view which shows the water jacket spacer before cutting a gate (bridge). It is a figure corresponding to FIG. 9 which concerns on a modification. FIG. 11 is a view corresponding to FIG. 11 (cross-sectional view taken along the line XIV-XIV in FIG. 13) according to a modified example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 and 2 show a cylinder block 1 of a multi-cylinder engine (hereinafter, simply referred to as an engine) to which the cooling structure according to the embodiment of the present invention is applied. In the present embodiment, the engine is an in-line 4-cylinder diesel engine, and the cylinder block 1 is provided with four cylinder bores 2 arranged in a row and a cylindrical cylinder bore wall 2a surrounding each cylinder bore 2. ing. Arbitrary adjacent cylinder bore walls 2a are integrally connected to each other, and the cylinder block 1 is called a siamese type cylinder block. The portion between the adjacent cylinder bores 2 in the cylinder bore wall 2a is constricted.

In the present embodiment, the engine is mounted in the engine room at the front of the vehicle so that the cylinder row direction is the vehicle width direction and the cylinder bore axis direction is the vertical direction. The front side of FIG. 1 and the lower side of FIG. 2 are the intake side where the intake air is introduced into the engine, and the back side of FIG. 1 and the upper side of FIG. 2 are the exhaust side where the exhaust gas is discharged from the engine. Further, a transmission (not shown) is attached to the end surface of the cylinder block 1 on the left side of the vehicle (right side in FIG. 2). In the following description, it is assumed that the engine is mounted on the vehicle.

In the present embodiment, a heater insertion hole 3 into which a block heater (not shown) used in a cold region is inserted by an occupant is provided in a portion of the cylinder block 1 on the intake side surface on the transmission side.

A cylinder head 35 is attached to the upper surface of the cylinder block 1 (one side of the cylinder block 1 in the cylinder bore axial direction) via a gasket 36 (see FIG. 10). On the upper surface of the cylinder block 1, eight screw holes 4 are formed in which bolts (not shown) for mounting and fixing the cylinder head 35 to the cylinder block 1 are screwed.

The cylinder block 1 is provided with a block water jacket 7 that surrounds the four cylinder bores 2 (four cylinder bore walls 2a). The block water jacket 7 is formed in a groove shape so as to open on the upper surface of the cylinder block 1. This opening is closed by the gasket 36 when the cylinder head 35 is attached to the upper surface of the cylinder block 1 via the gasket 36.

The inner side wall of the block water jacket 7 is composed of a cylinder bore wall 2a. The inner side wall surface of the block water jacket 7 is the outer side surface of the cylinder bore wall 2a.
The block water jacket 7 is curved inward so as to approach a virtual central plane including all the center lines of the four cylinder bores 2 corresponding to the intake side and the exhaust side portions between the adjacent cylinder bores 2 in the cylinder bore wall 2a. ing. Hereinafter, each of the intake side and exhaust side portions between the adjacent cylinder bores 2 in the cylinder bore wall 2a is referred to as a constriction portion 2b. In the present embodiment, the cylinder bore wall 2a is provided with six constricted portions 2b.

The block water jacket 7 is provided with a coolant introduction portion 7a for introducing the coolant into the block water jacket 7 on the intake side and the counter-transmission side.

A coolant inlet 8 for allowing a coolant (engine cooling water) to flow into the block water jacket 7 is provided on a portion of the cylinder block 1 on the side surface on the intake side on the counter-transmission side. The coolant inlet 8 communicates with the coolant introduction portion 7a via a communication passage 9 (see FIG. 3) having a rectangular cross section provided on the side wall portion on the intake side of the cylinder block 1. As a result, the coolant inlet 8 communicates with the block water jacket 7 (specifically, the outer flow path 7c described later). The coolant inlet 8 is connected to a water pump discharge port (not shown). As a result, the coolant discharged from the discharge port of the water pump is introduced into the coolant introduction section 7a via the coolant inlet 8 and the communication passage 9, and the block water jacket 7 (specifically, the block water jacket 7) is introduced from the coolant introduction section 7a. , Flows into the outer flow path 7c) described later.

As shown in FIG. 3, the communication passage 9 is open to the outer side wall surface of the block water jacket 7 (specifically, the side wall surface of the coolant introduction portion 7a). The lower surface of this opening is located at a height higher than the bottom surface of the coolant introduction portion 7a, and a step is formed between the lower surface of the opening and the bottom surface of the coolant introduction portion 7a. This step is die-cut between the mold for the communication passage 9 when casting the cylinder block 1 (die-cut on the coolant inlet 8 side) and the mold for the block water jacket 7 (die-cut on the upper side). It is caused by the relationship of.

As shown in FIGS. 4 to 11, a tubular water jacket spacer 11 having a peripheral wall portion 12 surrounding the periphery of the four cylinder bores 2 (four cylinder bore walls 2a) is housed in the block water jacket 7. .. The water jacket spacer 11 is made of resin. The height of the peripheral wall portion 12 (length in the cylinder bore axial direction) is substantially the same as the groove depth (length in the cylinder bore axial direction) of the block water jacket 7.

The water jacket spacer 11 has an inner flow path 7b located inside the peripheral wall portion 12 (on the side of the cylinder bore wall 2a) and the outside of the peripheral wall portion 12 (on the side of the cylinder bore wall 2a) in the water jacket 7 by the peripheral wall portion 12 of the water jacket spacer 11. It is configured to form an outer flow path 7c located on the side opposite to the cylinder bore wall 2a (particularly see FIG. 10). The width of the inner flow path 7b (distance between the inner surface of the peripheral wall portion 12 and the inner side wall surface of the water jacket 7) is the width of the outer flow path 7c (the outer surface of the peripheral wall portion 12 and the water jacket 7). It is smaller than the distance between the outer side wall surface). The peripheral wall portion 12 of the water jacket spacer 11 corresponds to each of the six constricted portions 2b of the cylinder bore wall 2a, and similarly to the water jacket 7, six inner curved portions 13 curved inward so as to approach the central plane. Have.

A portion of the lower end of the peripheral wall portion 12 of the water jacket spacer 11 corresponding to the coolant introduction portion 7a is provided with an extension portion 14 extending so as to cover the upper side of the bottom surface of the coolant introduction portion 7a. The upper surface of the extension portion 14 is located at the same height as the lower surface of the opening of the communication passage 9, and the extension portion 14 eliminates the step. If the step is left as it is, the flow of the coolant introduced from the communication passage 9 to the coolant introduction portion 7a is disturbed by the step, but the step is eliminated by the extension portion 14. Therefore, it is possible to suppress the flow of the coolant from being disturbed.

The coolant introduction portion 7a is inclined toward the exhaust side toward the transmission side and extends in a plan view. The downstream end of the coolant introduction portion 7a is connected to a portion of the outer flow path 7c on the counter-transmission side. As a result, the coolant inlet 8 is a coolant inlet to the outer flow path 7c and communicates with the portion of the outer flow path 7c on the counter-transmission side. As shown in FIGS. 4 and 5, most of the coolant flowing into the outer flow path 7c from the coolant introduction portion 7a due to the inclination of the coolant introduction portion 7a is the reaction of the peripheral wall portion 12 of the water jacket spacer 11. It flows toward the exhaust side along the outer surface of the transmission side portion. The remaining coolant flows toward the transmission side along the outer surface of the intake side portion of the peripheral wall portion 12 (see arrows in FIGS. 4 and 5).

Although not shown, the cooling liquid flowing through the anti-transmission side portion of the outer flow path 7c is applied to the end portion of the cylinder head 35 and the gasket 36 on the anti-transmission side, and the head water jacket 35a of the cylinder head 35 (FIG. An inflow hole for inflowing into (see 10) is formed. The inflow holes of the cylinder head 35 and the gasket 36 are located above the portion of the outer flow path 7c on the anti-transmission side, and communicate the outer flow path 7c to the head water jacket 35a in a state of communicating with each other in the vertical direction. Let me.

Since the coolant immediately after flowing into the outer flow path 7c from the coolant introduction portion 7a and trying to flow toward the exhaust side is the coolant just discharged from the discharge port of the water pump. The flow is strong and tries to flow vigorously to the upper side. As a result, a part of the coolant that tends to flow toward the exhaust side flows into the end portion of the headwater jacket 35a extending in the cylinder row direction on the anti-transmission side through the inflow hole. The coolant that has not flowed into the inflow hole has the anti-transmission side portion, the exhaust side portion, the transmission side portion, and the intake air in the outer flow path 7c so as to substantially go around the outer flow path 7c. It flows through the side portions in order (see the arrows in FIGS. 6 to 8). That is, the path of the coolant that flows into the outer flow path 7c from the coolant inlet 8 and flows through the outer flow path 7c is basically the portion of the outer flow path 7c from the counter-transmission side to the exhaust side. The path is such that it passes through the transmission side portion in order and flows to the intake side portion, and the cooling water flowing through the outer flow path 7c flows in a substantially U shape in a plan view.

On the outer surface (the surface on the outer flow path 7c side) of the peripheral wall portion 12 of the water jacket spacer 11, a coolant guide slope 15 for lifting the coolant upward is formed so as to be downstream of the outer flow path 7c. There is. As shown in FIG. 5, the coolant guide slope 15 extends from the base end portion of the extension portion 14 to the exhaust side at the portion of the peripheral wall portion 12 on the anti-transmission side, and from the middle thereof toward the exhaust side. Inclined upward, the exhaust side portion of the peripheral wall portion 12 toward the transmission side so as to be continuous with the coolant guide slope 15 in the counter-transmission side portion of the peripheral wall portion 12, as shown in FIG. Inclined upward, in the transmission side portion of the peripheral wall portion 12, as shown in FIG. 7, upward toward the intake side so as to be continuous with the coolant guide slope 15 in the exhaust side portion of the peripheral wall portion 12. As shown in FIG. 8, the portion of the peripheral wall portion 12 on the exhaust side that is inclined upwards toward the anti-transmission side so as to be continuous with the coolant guide slope 15 in the portion of the peripheral wall portion 12 on the transmission side. It is tilted. The coolant guide slope 15 on the exhaust side of the peripheral wall portion 12 is inclined downward from the position corresponding to the second cylinder bore 2 from the anti-transmission side toward the anti-transmission side on the anti-transmission side. is doing. This is to lift the coolant flowing toward the transmission side, which has flowed from the coolant introduction portion 7a into the outer flow path 7c, upward (see the arrow toward the right side in FIG. 8).

The coolant that has substantially circled the outer flow path 7c and the coolant that has flowed into the outer flow path 7c from the coolant introduction portion 7a and has flowed toward the transmission side are provided on the side wall surface on the intake side of the cylinder block 1. It flows from the coolant outlet 5 (see FIG. 1) to an oil cooler (not shown).

A part of the coolant flowing through the outer flow path 7c flows to the inner flow path 7b through the six communication holes 19 described later, and the six inner flow paths 7b described later flow from the inner flow path 7b, as will be described in detail later. It flows into the headwater jacket 35a through the inter-bore flow path 31.

The coolant that has flowed into the headwater jacket 35a from the inflow hole flows from the anti-transmission side to the transmission side in the headwater jacket 35a, and on the way, passes through the inter-bore flow path 31 to the headwater jacket 35a. It merges with the inflowing coolant. The cooling liquid thus merged flows out to the outside of the cylinder head 35 from the outlet provided on the end face of the cylinder head 35 on the transmission side. The coolant flowing out from this outlet and the coolant that has passed through the oil cooler are sucked into the suction port of the water pump after passing through the radiator.

An upper flange 16 projecting to the outside of the peripheral wall portion 12 (that is, projecting to the outer flow path 7c) is formed at the upper end portion of the outer surface of the peripheral wall portion 12 of the water jacket spacer 11. The upper flange 16 is formed in substantially the entire peripheral direction of the peripheral wall portion 12 except for the portion on the anti-transmission side (the portion corresponding to the inflow hole). The upper flange 16 suppresses the cooling liquid flowing through the outer flow path 7c from flowing beyond the upper end of the peripheral wall portion 12 into the inner flow path 7b.

Further, as shown in FIGS. 5 and 6, a part of the outer surface of the peripheral wall portion 12 in the circumferential direction is substantially parallel to the upper flange 16 with a predetermined space below the upper flange 16. A lower flange 17 extending in the circumferential direction of the peripheral wall portion 12 is formed. The lower flange 17 is formed in a portion corresponding to the upstream side of the outer flow path 7c in the circumferential direction of the peripheral wall portion 12, except for the portion corresponding to the inflow hole. That is, in the upstream portion of the outer flow path 7c, as described above, the coolant is about to flow vigorously to the upper side, so that the coolant is discharged by the double flange of the upper flange 16 and the lower flange 17. It is designed to prevent it from flowing into the inner flow path 7b beyond the upper end of the peripheral wall portion 12. A notch 17a is formed in the lower flange 17 so as to allow the cooling liquid to flow into the communication hole 19 in a portion directly below the communication hole 19 described later.

As shown in FIGS. 4 and 8, the transmission side and lower portion of the peripheral wall portion 12 on the intake side is notched to avoid interference with the block heater inserted into the heater insertion hole 3. The portion 18 is formed.

As shown in FIGS. 4, 6, 8 to 11, the peripheral wall portion 12 of the water jacket spacer 11 has an inner flow at a position corresponding to the constricted portion 2b of the cylinder bore wall 2a (that is, the inner curved portion 13). Communication holes 19 (six communication holes 19 in total in this embodiment) are formed to communicate the road 7b and the outer flow path 7c. These communication holes 19 are formed in the vicinity of the upper end of the peripheral wall portion 12 (near the end portion on the cylinder head 35 side). A part of the cooling liquid flowing through the outer flow path 7c flows to the inner flow path 7b through these communication holes 19.

Each communication hole 19 is formed in a vertically long rectangular cross section. That is, the vertical length of each communication hole 19 is made larger than the lateral width (length in the cylinder row direction) of the communication hole 19.

As shown in FIGS. 9 to 11, an outer flow path is provided on the lower side (anti-cylinder head 35 side) of each communication hole 19 on the inner surface (inner flow path 7b side surface) of the peripheral wall portion 12. A protruding portion 20 is provided on the inner flow path 7b so that at least a part of the coolant flowing from the communication hole 19 through the communication hole 19 into the inner flow path 7b can easily flow to the upper side (cylinder head 35 side). ing.

In the present embodiment, the lateral width (length in the cylinder row direction) of each protrusion 20 is made smaller than the lateral width of the corresponding communication hole 19. The amount of protrusion of each protrusion 20 is as large as possible, and the tip of the protrusion 20 does not come into contact with the inner side wall surface (outer side surface of the cylinder bore wall 2a) of the water jacket 7 even if there is a manufacturing error. Is set to. Therefore, although a gap is formed between the protruding tip of each protruding portion 20 and the inner side wall surface of the water jacket 7, the cooling liquid that has flowed into the inner flow path 7b through the communication hole 19 is the gap. It is difficult to flow from the bottom to the bottom.

In the present embodiment, in each protrusion 20, the upper surface of the protrusion 20 is the same as the lower portion of the inner peripheral surface of the corresponding communication hole 19, and the inner circumference of the corresponding communication hole 19 is the same. It is formed to be continuous with the lower part of the surface.

Further, in the present embodiment, the upper surface of each protruding portion 20 is an inclined surface 20a inclined so as to be located on the upper side toward the protruding tip side. As described above, since the upper surface of each protrusion 20 is the same surface as the lower portion of the inner peripheral surface of the corresponding communication hole 19, the portion is the same as the upper surface of each protrusion 20. The lower inclined surface 19a is inclined at an angle (inclined so as to be located on the upper side toward the inner flow path 7b side). The inclined surface 20a and the lower inclined surface 19a of the protrusion 20 make it easier for the cooling liquid that has flowed into the inner flow path 7b through the communication hole 19 to flow more easily on the upper side.

Further, in the present embodiment, the upper portion of the inner peripheral surface of each communication hole 19 is an upper inclined surface 19b inclined so as to be located on the lower side toward the inner flow path 7b side. An inclined surface 16a inclined so as to be the same surface as the upper inclined surface 19b is formed in a portion of the lower surface of the upper flange 16 located above each communication hole 19.

As shown in FIGS. 10 and 11, in each constricted portion 2b of the cylinder bore wall 2a, a part of the cooling liquid that has flowed from the outer flow path 7c through the communication hole 19 into the inner flow path 7b is applied to the cylinder head 35. An inter-bore flow path 31 for flowing into the headwater jacket 35a is provided.

The inter-bore flow path 31 of each constricted portion 2b is composed of an upstream side flow path 31a and a downstream side flow path 31b, and the upstream end of the downstream side flow path 31b is connected to the downstream end of the upstream side flow path 31a. .. The upstream end of the upstream flow path 31a has a larger diameter than the other portion of the upstream flow path 31a and opens to the inner side wall surface of the water jacket 7. The opening of the inner side wall surface in the upstream side flow path 31a corresponds to the inlet 31c of the inter-bore flow path 31. The downstream end of the downstream flow path 31b is open to the upper surface of the cylinder bore wall 2a. The opening on the upper surface of the cylinder block 1 in the downstream flow path 31b corresponds to the outlet 31d of the inter-bore flow path 31.

Both the upstream side flow path 31a and the downstream side flow path 31b extend so as to incline downward toward the central plane. The inclination angle of the upstream side flow path 31a on the acute angle side with respect to the horizontal is smaller than the inclination angle of the downstream side flow path 31b on the acute angle side with respect to the horizontal. Both the upstream side flow path 31a and the downstream side flow path 31b are formed by a drill.

The downstream end of the downstream flow path 31b (opening on the upper surface of the cylinder block 1) is a headwater jacket of the cylinder head 35 via a connection hole 36a provided in the gasket 36 and a connection flow path 35b provided in the cylinder head 35. It is connected to 35a.

Each protrusion 20 is located at the same position as the inlet 31c of the inter-bore flow path 31 of the corresponding constriction 2b in the cylinder row direction. Further, the height position at the protruding tip on the upper surface of each protruding portion 20 is located at a position lower than the height position of the inlet 31c of the inter-bore flow path 31 of the corresponding constricted portion 2b. Further, the upper inclined surface 19b of each communication hole 19 is inclined so as to direct the inlet 31c of the inter-bore flow path 31 of the corresponding constricted portion 2b.

A part of the coolant flowing into the inner flow path 7b through the communication hole 19 flows toward the constricted portion 2b of the cylinder bore wall 2a along the upper surface of the protruding portion 20, and the constricted portion 2b of the cylinder bore wall 2a. (Strictly speaking, it corresponds to the portion of the constricted portion 2b on the outer side surface of the cylinder bore wall 2a). The coolant that hits the constricted portion 2b does not easily flow downward from the gap between the protruding tip of each protruding portion 20 and the inner side wall surface of the water jacket 7, and thus easily flows upward. Therefore, after hitting the constricted portion 2b of the cylinder bore wall 2a, it basically flows upward, and the cooling liquid flowing upward thereof causes a particularly high temperature in the constricted portion 2b of the cylinder bore wall 2a. The end portion on the cylinder head 7 side (upper side) and its vicinity are cooled.

In the present embodiment, the vertical length of each communication hole 19 is made larger than the horizontal width of the communication hole 19, so that the constricted portion 2b of the cylinder bore wall 2a is cooled as wide as possible in the vertical direction. .. Further, by reducing the width of each communication hole 19, the flow velocity of the coolant is increased as much as possible, and the coolant is vigorously applied to the constricted portion 2b of the cylinder bore wall 2a. Further, since the width of each protrusion 20 is smaller than the width of the corresponding communication hole 19, among the coolant flowing into the inner flow path 7b through the communication hole 19, the direction of the cylinder row of the protrusion 20. The coolant flowing on both sides tends to flow downward because there is no protrusion 20. However, as described above, the lower portion (lower inclined surface 19a) on the inner peripheral surface of the communication hole 19 is inclined so as to be located on the upper side toward the inner flow path 7b side, and the flow velocity of the cooling liquid. The coolant flowing on both sides of the protruding portion 20 in the cylinder row direction hits a portion of the constricted portion 2b of the cylinder bore wall 2a at substantially the same height as the protruding portion 20. This cools a wider range in the vertical direction of the constricted portion 2b of the cylinder bore wall 2a.

A part of the coolant flowing upward by the protrusion 20 flows into the inlet 31c of the inter-bore flow path 31 located at the same position in the cylinder row direction as the protrusion 20 (sucked into the cylinder head 35 side). Further, the cooling liquid flowing through the upper portion in the communication hole 19 and flowing into the inner flow path 7b is guided by the upper inclined surface 19b, and the inlet 31c of the inter-bore flow path 31 to which the upper inclined surface 19b points. It becomes easy to flow into. Then, the cooling liquid flowing into the inlet 31c of the inter-bore flow path 31 flows in order through the upstream side flow path 31a and the downstream side flow path 31b, thereby further cooling the constricted portion 2b of the cylinder bore wall 2a from the inside of the wall. After that, the coolant exits from the outlet 31d of the inter-bore flow path 31 and flows into the headwater jacket 35a through the connection hole 36a of the gasket 36 and the connection flow path 35b of the cylinder head 35.

Here, the resin water jacket spacer 11 is molded by injection molding. When the water jacket spacer 11 is formed, the peripheral wall portion 12 is likely to be deformed so that the intake side portion and the exhaust side portion are separated from each other.

Therefore, as shown in FIG. 12, at the time of molding the water jacket spacer 11, one or a plurality of two portions on the inner surface of the peripheral wall portion 12 facing each other in the direction perpendicular to the central plane are connected to each other. Bridge 22 is formed. In the present embodiment, three bridges 22 are formed, and each bridge 22 connects to each other on the inner surface of the peripheral wall portion 12 a portion provided with a protrusion 20 facing the central plane in a direction perpendicular to the central plane. do. Each bridge 22 suppresses deformation such that the intake side portion and the exhaust side portion of the peripheral wall portion 12 are separated from each other when the water jacket spacer 11 is formed. Each bridge 22 is used as a gate when forming the water jacket spacer 11, and the bridge 22 is removed by cutting both ends of the gate.

When cutting the gate, the protrusion 20 can be formed by cutting with a part of the gate left. In the present embodiment, the entire protruding portion 20 is formed by the remaining gate portion left by cutting the gate during molding of the water jacket spacer 11. It is also possible to form a portion of the protruding portion 20 on the protruding tip side, instead of the entire protruding portion 20, by the remaining portion of the gate.

Therefore, in the present embodiment, the inner flow path 7b and the outer flow path 7c are provided at positions corresponding to the constricted portion 2b of the cylinder bore wall 2a (inner curved portion 13) in the vicinity of the upper end of the peripheral wall portion 12 of the water jacket spacer 11. A communication hole 19 is formed to communicate with each other, and an inner flow is formed from the outer flow path 7c through the communication hole 19 in the lower portion of the communication hole 19 on the surface of the peripheral wall portion 12 of the water jacket spacer 11 on the inner flow path 7b side. Since a protruding portion 20 is provided in the inner flow path 7b to facilitate the flow of at least a part of the coolant flowing into the path 7b upward, the cooling liquid flows into the inner flow path 7b through the communication hole 19. The resulting coolant can be applied to the constricted portion 2b of the cylinder bore wall 2a, and the coolant that hits the constricted portion 2b can basically be flowed upward, and the coolant flowing upward can be used. Of the constricted portion 2b of the cylinder bore wall 2a, the end portion on the cylinder head 7 side and its vicinity, which are particularly hot, can be effectively cooled.

Further, among the cooling liquids that have flowed into the inner flow path 7b through the communication hole 19, the amount of the cooling liquid that flows downward is reduced by the protruding portion 20, so that the protruding portion 20 is formed in the inner flow path 7b. Below, it is difficult for fresh coolant to flow, and the coolant is in a stagnant state. As a result, the heat retention performance of the combustion chamber of the engine can be ensured.

Therefore, the portion of the cylinder bore wall 2a on the cylinder head 7 side of the constricted portion 2b can be effectively cooled to ensure the cooling performance of the combustion chamber of the engine, and the cooling liquid of the inner flow path 7b can be used to cool the combustion chamber. The heat retention performance can be ensured.

13 and 14 show modified examples of the above embodiment.

In this modification, the inner side wall surface (outer side surface of the cylinder bore wall 2a) of the water jacket 7 is a portion on the upper side (cylinder head 35 side) of the constricted portion 2b and a portion on the lower side (anti-cylinder head 35 side). It has a drive-in portion 2c that is recessed inside the wall. The protruding portion 20 is provided on the surface of the peripheral wall portion 12 on the inner flow path 7b side so that the tip portion of the protruding portion 20 enters the driving portion 2c.

When the inner side wall surface of the water jacket 7 does not have the driving portion 2c as described above, it is below the protruding portion 20 in the peripheral wall portion 12 of the water jacket spacer 11 at the position corresponding to the constricted portion 2b. The gap between the side portion and the inner side wall surface of the water jacket 7 is increased by the amount of protrusion of the protrusion 20. On the other hand, when the inner side wall surface of the water jacket 7 has the driving portion 2c, the portion of the peripheral wall portion 12 of the water jacket spacer 11 below the protruding portion 20 and the inside of the water jacket 7. The gap between the side wall surface and the portion below the driven portion 2c can be reduced regardless of the amount of protrusion of the protruding portion 20. Therefore, it is possible to prevent the amount of the coolant in the inner flow path 7b from becoming unnecessarily large.

Further, even if the error of the protrusion amount of the protrusion 20 is large, the protrusion 20 can be prevented from interfering with the inner side wall surface of the water jacket 7, and as a result, the water jacket spacer 11 can be easily manufactured. Can be done.

The present invention is not limited to the above embodiment, and can be substituted as long as it does not deviate from the gist of the claims.

For example, in the above embodiment, the upper surface of each protrusion 20 is continuous with the lower portion of the inner peripheral surface of the corresponding communication hole 19, but the upper surface of the protrusion 20 is the corresponding communication. Even if it is located below the lower portion of the inner peripheral surface of the hole 19 and a step is generated between the upper surface of the protrusion 20 and the lower portion of the inner peripheral surface of the communication hole 19. good. However, in order to facilitate the flow of the cooling liquid flowing into the inner flow path 7b through the communication hole 19 upward, it is necessary to make the step amount as small as possible.

Further, in the above embodiment, the upper surface of each protrusion 20 is inclined so as to be located on the upper side toward the protrusion tip side, but it may extend horizontally. Further, the lower portion of the inner peripheral surface of each communication hole 19 may also extend horizontally. However, at least one of the upper surface of each protrusion 20 and the lower portion of the inner peripheral surface of each communication hole 19 (particularly the upper surface of each protrusion 20) is inclined as in the above embodiment. Is preferable. Further, the upper portion of the inner peripheral surface of each communication hole 19 may also extend horizontally.

Further, in the above embodiment, the width of each protrusion 20 is smaller than the width of the corresponding communication hole 19, but may be the same as or larger than the width of the corresponding communication hole 19. In this case, the protrusion 20 makes it possible to facilitate the flow of substantially all of the coolant that has flowed into the inner flow path 7b through the communication hole 19 upward.

Further, in the above embodiment, the engine is mounted on the vehicle so that the cylinder bore axial direction is the vertical direction, but the present invention is not limited to this, and for example, the engine is mounted on the vehicle so that the cylinder bore axial direction is the horizontal direction. The present invention can also be applied to the cooling structure of an engine.

Furthermore, in the above embodiment, the present invention is applied to a multi-cylinder diesel engine, but the present invention can be suitably applied to any engine as long as it is a multi-cylinder compression ignition type engine.

The above embodiments are merely examples, and the scope of the present invention should not be construed in a limited manner. The scope of the present invention is defined by the scope of the claims, and all modifications and modifications belonging to the equivalent scope of the claims are within the scope of the present invention.

In the present invention, a plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores are provided, and a cylinder block to which a cylinder head is attached to one surface in the axial direction of the cylinder bore and a water jacket of the cylinder block are housed in the cylinder block. It is useful for a cooling structure of a multi-cylinder engine provided with a water jacket spacer having a peripheral wall portion surrounding the periphery of the plurality of cylinder bores, and particularly when the multi-cylinder engine is a compression ignition type engine such as a diesel engine. It is useful for.

1 Cylinder block 2 Cylinder bore 7 Block water jacket 7b Inner flow path 7c Outer flow path 8 Coolant inlet 11 Water jacket spacer 12 Peripheral wall 19 Communication hole 20 Protrusion 20a Inclined surface 22 Bridge (gate)
35 Cylinder head

Claims (7)

A plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores are provided, a cylinder block in which a cylinder head is attached to one surface in the axial direction of the cylinder bore, and a plurality of cylinder blocks housed in the water jacket of the cylinder block. A cooling structure for a multi-cylinder engine with a water jacket spacer having a peripheral wall surrounding the cylinder bore of the engine.
The water jacket spacer is configured such that an inner flow path located inside the peripheral wall portion and an outer flow path located outside the peripheral wall portion are formed in the water jacket by the peripheral wall portion. ,
The cylinder block is provided with a coolant inlet to the outer flow path that communicates with the outer flow path.
A communication hole for communicating the inner flow path and the outer flow path is formed in the peripheral wall portion at a position corresponding to the adjacent cylinder bores.
At least a part of the coolant that has flowed from the outer flow path through the communication hole into the inner flow path to the portion on the inner flow path side surface of the peripheral wall portion on the anti-cylinder head side of the communication hole. A protruding portion is provided in the inner flow path to facilitate flow to the head side .
The communication hole is formed in the vicinity of the end portion on the cylinder head side of the peripheral wall portion.
The protrusion is a cooling structure for a multi-cylinder engine, wherein the surface of the protrusion on the cylinder head side is formed so as to be continuous with a portion of the inner peripheral surface of the communication hole on the anti-cylinder head side. .. In the cooling structure according to claim 1 Symbol placement multi-cylinder engine,
A cooling structure for a multi-cylinder engine, characterized in that the surface of the protruding portion on the cylinder head side is inclined so as to be located closer to the cylinder head side toward the protruding tip side. In the cooling structure of the multi-cylinder engine according to claim 1 or 2.
The water jacket spacer is made of resin and is made of resin.
A cooling structure for a multi-cylinder engine, wherein at least a portion of the protruding portion on the protruding tip side is formed by a remaining gate portion remaining by cutting the gate during molding of the water jacket spacer. A plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores are provided, a cylinder block in which a cylinder head is attached to one surface in the axial direction of the cylinder bore, and a plurality of cylinder blocks housed in the water jacket of the cylinder block. A cooling structure for a multi-cylinder engine with a water jacket spacer having a peripheral wall surrounding the cylinder bore of the.
The water jacket spacer is configured such that an inner flow path located inside the peripheral wall portion and an outer flow path located outside the peripheral wall portion are formed in the water jacket by the peripheral wall portion. ,
The cylinder block is provided with a coolant inlet to the outer flow path that communicates with the outer flow path.
A communication hole for communicating the inner flow path and the outer flow path is formed in the peripheral wall portion at a position corresponding to the adjacent cylinder bores.
At least a part of the coolant that has flowed from the outer flow path through the communication hole into the inner flow path to the portion on the inner flow path side surface of the peripheral wall portion on the anti-cylinder head side of the communication hole. A protruding portion is provided in the inner flow path to facilitate flow to the head side.
A cooling structure for a multi-cylinder engine, characterized in that the surface of the protruding portion on the cylinder head side is inclined so as to be located closer to the cylinder head side toward the protruding tip side. In the cooling structure of the multi-cylinder engine according to claim 4.
The water jacket spacer is made of resin and is made of resin.
A cooling structure for a multi-cylinder engine, wherein at least a portion of the protruding portion on the protruding tip side is formed by a remaining gate portion remaining by cutting the gate during molding of the water jacket spacer. A plurality of cylinder bores and a water jacket surrounding the plurality of cylinder bores are provided, a cylinder block in which a cylinder head is attached to one surface in the axial direction of the cylinder bore, and a plurality of cylinder blocks housed in the water jacket of the cylinder block. A cooling structure for a multi-cylinder engine with a water jacket spacer having a peripheral wall surrounding the cylinder bore of the engine.
The water jacket spacer is configured such that an inner flow path located inside the peripheral wall portion and an outer flow path located outside the peripheral wall portion are formed in the water jacket by the peripheral wall portion. ,
The cylinder block is provided with a coolant inlet to the outer flow path that communicates with the outer flow path.
A communication hole for communicating the inner flow path and the outer flow path is formed in the peripheral wall portion at a position corresponding to the adjacent cylinder bores.
At least a part of the coolant that has flowed from the outer flow path through the communication hole into the inner flow path to the portion on the inner flow path side surface of the peripheral wall portion on the anti-cylinder head side of the communication hole. A protruding portion is provided in the inner flow path to facilitate flow to the head side.
The water jacket spacer is made of resin and is made of resin.
A cooling structure for a multi-cylinder engine, wherein at least a portion of the protruding portion on the protruding tip side is formed by a remaining gate portion remaining by cutting the gate during molding of the water jacket spacer. In the cooling structure of the multi-cylinder engine according to any one of claims 1 to 6.
The inner side wall surface of the water jacket has a drive-in portion recessed inside the wall in a portion on the cylinder head side between adjacent cylinder bores rather than a portion on the anti-cylinder head side thereof.
The protrusion is a cooling structure for a multi-cylinder engine, characterized in that the protrusion is provided on the inner flow path side surface of the peripheral wall portion so that the tip of the protrusion enters the drive-in portion.

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