JP2000356131A - Cooling device of vee-engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To equalize the temperature and quantity of the cooling water flowing into each bank to solve the temperature difference between the banks by providing such a structure as to distribute the cooling water discharged from a water pump to both the banks of an engine after passing through an oil cooler. SOLUTION: The cooling water discharged from a water pump 10 is introduced into an oil cooler 15 through a cooler inlet pipe 14 to perform heat- exchange with oil, then carried to a connecting pipe 18 through a connecting pipe 17, and run into each cylinder block 4 of a right bank 3 and then a left bank 2. The cooling water within each cylinder block 4 flows from the rear to the front, and an upward flow directing cylinder heads 5, 6 is also generated together with this to cool an engine 1. The cooling water carried in each bank 2, 3 is introduced to a thermostat housing 24 through outlet pipes 22, 23, and in cooling, the cooling water is entirely returned to the water pump 10 through a bypass pipe 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cooling device applied to various V-type engines such as a V-type diesel engine.

[0002]

2. Description of the Related Art Usually, a water cooling system for a V-type engine is as follows (Japanese Patent Application Laid-Open No. 62-91615,
7-189694, etc.). That is, a water pump is provided at one end side of the engine in the crankshaft direction, and while cooling water discharged from the water pump is distributed to both banks of the engine, and each bank is passed in the crankshaft direction,
At the other end, they are collected by a collecting pipe, sent to a radiator, and returned to a water pump.

[0003]

However, there are cases where oil is cooled using a water-cooled oil cooler. At this time, if the cooling water after cooling the engine is used as a cooling medium for the oil, the cooling water temperature is already high, and there is a possibility that the cooling of the oil may be insufficient.

Therefore, the layout of the oil cooler shown in FIGS. 4 and 5 can be considered. In the figure, a
Is a water pump, b and c are cylinder blocks and cylinder heads of each bank of the engine, d is a collecting pipe, e is a radiator, and f is an oil cooler.

In FIG. 4, after the flow of the cooling water is branched immediately downstream of the water pump a, the cooling water is passed through an oil cooler f before entering the cylinder block b of one bank. In FIG. 5, the cylinder block b of one bank is shown.
The cooling water flow is taken out from the upstream part of the pipe, and is sent to the collecting pipe d after passing through the oil cooler f. According to these, since the cooling water before cooling the engine is used as the oil cooling medium, sufficient oil cooling performance can be obtained.

However, in the layout shown in FIG. 4, high-temperature cooling water after passing through the oil cooler flows through only one of the banks having the oil cooler f, so that a temperature difference occurs between the banks. Also in the layout of FIG. 5, since the amount of cooling water in one bank having the oil cooler f is smaller than that in the other bank, a temperature difference occurs between the banks.

[0007]

A cooling device for a V-type engine according to the present invention is configured to distribute cooling water discharged from a water pump to both banks of the engine after passing through an oil cooler.

According to this, since the cooling water after passing through the oil cooler is distributed to both the banks, the temperature and the amount of the cooling water flowing into each bank become equal, and the temperature difference between the banks can be eliminated.

The water pump is provided at one end of the engine in the crankshaft direction, and the other end of the engine in the crankshaft direction is provided with a connecting pipe for connecting the water jackets of both banks of the engine. Is preferably supplied to the connecting pipe after passing through the oil cooler and distributed from the connecting pipe to the water jackets of both banks of the engine.

[0010] The communication pipe has an inlet for introducing cooling water after passing through the oil cooler, and at least two outlets which are sequentially connected from the inlet in a flow direction of the cooling water and communicate with water jackets of the respective banks of the engine. It is preferable to have a throttle portion for narrowing the passage area in the pipe at a position between the outlets.

[0011] Further, a portion between the outlets of the connecting pipe is tapered so as to be narrowed toward the upstream side, and the maximum throttled portion forms the narrowed portion, and is provided at a position immediately downstream of the outlet on the upstream side. Is preferred.

Preferably, the connecting pipe is formed integrally with the flywheel housing.

[0013]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows a cooling device for a V-type engine according to the present invention. The V-type engine 1 has left and right banks 2 and 3. A lower portion of the banks 2 and 3 is constituted by a cylinder block 4, and a top portion is constituted by cylinder heads 5 and 6. A crank gear 7 is provided at one end of the crankshaft (not shown) of the engine 1, that is, at the front end.
An idle gear 8 and a pump gear 9 that are rotatably driven by a crank gear 7 are rotatably mounted on a front end of the engine 1. Further, a water pump 10 that is driven by a pump gear 9 is mounted on a front end of the engine 1. It is attached. The water pump 10 sucks cooling water from two inlets 11 and 12, and discharges the cooling water from one outlet 13. In the drawing, the flow direction of the cooling water is indicated by white arrows.

An outlet 13 of the water pump 10 projects rightward of the engine 1 and is directed rearward. Exit 1
The inlet of the cooler inlet pipe 14 is connected to 3. The cooler inlet pipe 14 extends rearward, and its outlet is connected to a cooling water inlet 16 of a water-cooled oil cooler 15. The oil cooler 15 performs heat exchange between oil (engine lubricating oil) and cooling water inside the oil cooler 15 to cool the oil. Oil cooler 15
Is connected to a bent connecting pipe 17. The oil cooler 15 is located at an intermediate portion of the engine 1 in the crankshaft direction, and the crankshaft direction matches the cooler longitudinal direction. The outlet of the oil cooler 15 is located at the rear end in the cooler longitudinal direction, and the connecting pipe 17 is connected thereto.

The connecting pipe 17 is bent in the middle and its outlet is directed to the left. Then, an inlet 19 of the communication pipe 18 is connected to the outlet.

The connecting pipe 18 is for connecting the left and right banks 2 and 3 of the engine 1, specifically, a water jacket (not shown) of the cylinder block 4 portion thereof, and in this case, a flywheel which is a housing member. It is provided integrally with the housing 20. That is, the connecting pipe 18 is provided integrally with the flywheel housing 20 normally provided at the other end in the crankshaft direction, that is, the rear end of the engine 1. The connecting pipe 18 extends right and left, has the inlet 19 at the right end thereof, and has two outlets 21 serially arranged in the pipe length direction (cooling water flow direction) from the inlet 19 in order. Are connected to the water jackets of the left and right banks 2 and 3.

At the front end of the engine 1, outlet pipes 22, 23 are provided on the front surfaces of the cylinder heads 5, 6 of the left and right banks 2, 3, respectively.
The outlet pipes 22 and 23 are extended to a central position between the banks 2 and 3, and the outlets thereof are connected to the thermostat housing 24. Thermostat housing 24
Has two built-in thermostats 25 and 26, one thermostat 25 is of a two-stage open type, and the other thermostat 26 is of a single-stage open type. A bypass-side outlet 27 is provided at the bottom of the thermostat housing 24, and is connected to a bypass pipe 28.
Is connected to the bypass-side inlet 11 of the water pump 10.

The upper part of the thermostat housing 24 is constituted by a housing cover 29 which can be opened and closed, and the housing cover 29 is provided with a radiator side outlet 30. The radiator side outlet 30 is connected to an inlet of a radiator (not shown) via a pipe (not shown). An outlet of the radiator is connected to a radiator-side inlet 12 of the water pump 10 by a piping (not shown).

The flow of cooling water in this cooling device is as follows. That is, the cooling water discharged from the water pump 10 flows backward through the cooler inlet pipe 14 and is introduced into the oil cooler 15. Then, heat exchange with the oil is completed here, and the oil is introduced into the connecting pipe 18 further rearward through the connecting pipe 17. In the connecting pipe 18, the right bank 3 flows out to the cylinder block 4 first, and then the left bank 2
Out of the cylinder block 4 is performed. Thus, the connecting pipe 18 distributes and supplies the introduced cooling water to the banks 2 and 3.

In the cylinder block 4 of each bank 2, 3, the flow is from the rear to the front, and together with this, the upward flow toward the cylinder heads 5, 6 is also generated. Thereby, cooling of the engine 1 is performed. The cooling water that has finished flowing through each bank 2, 3 is led out to outlet pipes 22, 23 and is introduced into a thermostat housing 24. When the thermostats 25 and 26 are all closed, the entire amount of the cooling water in the thermostat housing 24 is returned to the water pump 10 through the bypass pipe 28. That is, since the cooling water does not pass through the radiator, the cooling water is not cooled. This is the case, for example, in a warm-up state immediately after starting.

As the engine warms up, the thermostat 2
When a part or all of the openings 5, 26 are opened, an amount of cooling water corresponding to the opening degree passes upward through the thermostats 25, 26,
It is drawn out from the radiator side outlet 30 and heads for the radiator through a pipe (not shown). Then, the cooling water is cooled in the radiator. Cooling water after cooling is also supplied from the radiator side inlet 12 to the water pump 1 through a pipe (not shown).
Returned to 0. The remaining amount of water not passing through the radiator is bypassed to the water pump 10 through the bypass pipe 28.

Although not shown, a route via a heater core for an indoor heater is provided in addition to the above route. Cooling water is replenished from the reserve tank to the radiator.

As described above, in this apparatus, the water pump 1
After passing through the oil cooler 15, the cooling water discharged from 0 is distributed and supplied to both banks 2 and 3 of the engine 1. In this way, the cooling water after passing through the oil cooler 15 can be equally distributed to the two banks 2 and 3, and the temperature difference between the banks 2 and 3 does not occur.

A water pump 10 is provided at one end of the engine 1 in the direction of the crankshaft, and a communication pipe 18 is provided at the other end of the engine 1 in the direction of the crankshaft. The cooling water discharged from the water pump 10 passes through the oil cooler 15 after passing through the oil cooler 15. Connecting pipe 1
8 from the connecting pipe 18 to both banks 2 of the engine 1
3, the engine 1 can be made more compact.

That is, in the present apparatus, the cooling water discharged from the water pump 10 is sent to the rear of the engine in front of the engine, passes through the oil cooler 15 in the middle thereof, and passes through both banks 2 and 3 from behind the engine. Then, the water pump 10 is returned to the front water pump 10. On the other hand, if the oil cooler 15 is passed in front of the engine and the cooling water is supplied to the left and right banks 2 and 3 from the front at the same time, the piping and the oil cooler 15 are densely arranged at the front end of the engine, and the layout on the front side is complicated. , It becomes large. Also, there is one pipe for returning cooling water from the rear of the engine to the front.
You need a book.

According to the layout of the present apparatus, problems such as complication of layout on the front side of the engine are eliminated, and the layout of each element can be performed efficiently, and compactness can be achieved.

In particular, since the oil cooler 15 is disposed at the middle and side of the engine 1 in the direction of the crankshaft, and its longitudinal direction coincides with the direction of the crankshaft, the length of the oil cooler 15 is effectively used, and (The cooler inlet pipe 14 and the connecting pipe 17) can be shortened.

The present apparatus is also characterized in that the communication pipe 18 is provided integrally with the flywheel housing 20. Hereinafter, the configuration of the flywheel housing 20 will be described in detail.

As shown in FIG. 2, the flywheel housing 20 is a cast integral product, and a fastening rib 31 protruding from the front surface thereof is joined to the rear surface of the engine 1 and fixed by a plurality of bolts. Has become. 32 is a bolt hole, the flywheel is located behind the housing 20, and its outer periphery is covered. Flywheel housing 20
A central hole 33 is provided at the center of the hole for inserting the rear end of the crankshaft. Numeral 34 denotes a reinforcing rib that extends around the fastening rib 31 from side to side and surrounds the center hole 33.

The connecting pipe 18 is formed integrally with the upper part of the flywheel housing 20. The connecting pipe 18 extends right and left and has a vertically long rectangular cross-sectional shape. Fastening rib 3
The outlets 21 are provided adjacent to the left and right outer sides of the vehicle 1 and face the front. Connecting pipe 18 on the right of exit 21 on the right
Is bent diagonally downward, and the entrance 19
Is provided. The left end of the connecting pipe 18 is open,
As shown in (5), it is closed by the cap 35, and the outflow of the cooling water is prevented.

As shown in FIG. 3, the fastening rib 31 protrudes forward from the connecting pipe 18. The outlet end of the outlet 21 is enlarged in a stepped manner, and the enlarged diameter portion 36 is formed in the cylinder block 4.
It is designed to be fitted into a tubular part (not shown) projecting from the spigot. The tubular portion forms an inlet of the water jacket in each bank 3. The ring portion 37 that defines the enlarged diameter portion 36 has a small gap 3 with the fastening rib 31.
8 and have a projection length equal to that of the fastening rib 31.

As shown in FIG. 2, the connecting pipe 18 is preferably tapered so that at least a portion between the left and right outlets 21 is narrowed toward the right side (upstream side). Here, the bending position A
The entirety of the portion on the left side (the connecting portion 39) is tapered so as to be narrowed toward the right side. The bending position A is located on the left side (directly downstream side) nearest to the center O of the right outlet 21. At this bent position A, the passage area of the connecting pipe 18 is reduced to the maximum. In this way, the constriction section 4 is placed in the connecting pipe 18 at the bending position A.
0 will be provided.

The connecting pipe 18 is bent at the bending position A,
An inlet side portion 41 is provided on the right side thereof, which is formed in a taper shape reverse to the above, that is, a taper shape narrowed toward the left side (downstream side). However, the taper angle is gentler than the connecting portion 39. The entrance 19 is provided at the right end of the entrance side portion 41. In this way, in the connecting pipe 18, the inlet 19, the right outlet 21, and the left outlet 21 are arranged in series in the cooling water flow direction in the order of the inlet 19 and each outlet 21.

When the connecting pipe 18 is provided integrally with the flywheel housing 20 as described above, the connecting pipe (collecting pipe) conventionally provided as an independent pipe becomes unnecessary, and the number of parts is reduced and the cost is reduced. I can do it. Usually, a flywheel housing is attached to the rear end of the engine, and this device utilizes this to integrate the connecting pipe. In addition, since one pipe is not required, a space margin is created, the layout is improved, and the arrangement of other accessories is facilitated. Thus, the rear end of the engine can be made compact.

Further, since the connecting pipe 18 serves as a reinforcing rib, the rigidity of the flywheel housing 20 can be improved, and the vibration noise can be reduced.

Further, since the throttle portion 40 is provided as described above, the amount of cooling water flowing out from each outlet 21 can be equalized, and the temperature difference between the banks 2 and 3 can be eliminated.

That is, the right outlet 21 is connected to the bent connecting pipe 1.
7 is located immediately downstream. In this case, under the influence of the bending in the connecting pipe 17, at the position of the right outlet 21, the flow sticks to the rear part in the pipe. Restrictor 40
Without this, the flow along the connecting pipe 17 at the position of the right outlet 21 becomes strong, and it is difficult for the right outlet 21 to flow out to the right outlet 21. Therefore, if the passage is narrowed on the downstream side of the right outlet 21, this becomes a resistance and easily flows out to the right outlet 21.

For this purpose, the throttle section 40 only needs to be located between the right outlet 21 and the left outlet 21.
However, the effect is greater if it is provided immediately downstream of the right outlet 21.

As described above, the embodiments of the present invention are not limited to those described above. For example, a plurality of outlets of the connecting pipe may be provided for each bank, and the narrowed portion may be formed as a projection without depending on the taper.

[0041]

The present invention exhibits the following excellent effects.

(1) The temperature and the amount of cooling water flowing into both banks are equalized, and the temperature difference between the banks can be eliminated.

(2) A compact engine can be achieved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment according to the present invention.

FIG. 2 is a front view of a flywheel housing.

FIG. 3 is a sectional view taken along the line III-III of FIG. 2;

FIG. 4 is a configuration diagram showing a proposal of a cooling device provided with an oil cooler.

FIG. 5 is a configuration diagram showing one proposal of a cooling device provided with an oil cooler.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 V-type engine 2 Left bank 3 Right bank 10 Water pump 15 Oil cooler 18 Communication pipe 19 Inlet 20 Flywheel housing 21 Outlet 40 Restrictor A Bending position

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Claims (5)

[Claims] 1. A cooling system for a V-type engine, wherein cooling water discharged from a water pump is distributed and supplied to both banks of the engine after passing through an oil cooler. 2. The water pump is provided at one end of the engine in the crankshaft direction, and the other end of the engine in the crankshaft direction is provided with a communication pipe connecting the water jackets of both banks of the engine. The cooling device for a V-type engine according to claim 1, wherein the discharged cooling water is supplied to the communication pipe after passing through the oil cooler, and is distributed and supplied to the water jackets of both banks of the engine from the communication pipe. 3. An inlet for introducing cooling water after passing through an oil cooler, at least two outlets serially connected in series with the flow of cooling water from the inlet and communicating with a water jacket of each bank of the engine. 3. The cooling device for a V-type engine according to claim 2, further comprising a throttle portion that narrows a pipe passage area at a position between the outlets. 4. A portion between the outlets of the connecting pipe having a tapered shape narrowed toward an upstream side, and a maximum throttled portion forms the narrowed portion and is provided at a position immediately downstream of the outlet on an upstream side. Item 4. A cooling device for a V-type engine according to Item 3. 5. The V according to claim 2, wherein the connecting pipe is formed integrally with the flywheel housing.
Type engine cooling system.