JP2857180B2 - V-type liquid-cooled engine cooling system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for a V-type liquid-cooled engine for a motorcycle, and more particularly, to simplifying the wiring of a coolant passage and providing coolant to each cylinder. The present invention relates to a structure of a coolant passage in which an amount can be easily adjusted. Although the present invention is applicable to a water-cooled or oil-cooled engine, the following description will be made for a water-cooled engine.

2. Description of the Related Art A cooling device for a water-cooled engine is, for example, provided with a cooling water pump in a crankcase, and connects the pump, a water cooling jacket of a cylinder, and a radiator through a cooling water passage, and cools the cooling water with a water cooling jacket. And a radiator. When this cooling device is used in a V-type engine, since the cylinders are spaced apart so as to form a V bank, it is necessary to branch the cooling water passage from the cooling water pump toward each cylinder. Conventionally, as such a branch structure of the cooling water passage, for example, the discharge port of the cooling water pump is branched into two, and
One cooling water hose is connected and routed outside the crankcase. The cooling water pump has only one outlet, and one cooling water hose connected to the outlet is connected in the middle. There are a structure in which the cooling water pump and each water cooling jacket are connected to each other through two cooling water passages branched and formed in a crankcase, and the like.

[Problems to be solved by the invention]

In the above structure, the two cooling water hoses are routed outside the crankcase, so that the wiring space becomes large and the handling of the hoses becomes complicated. In this case, since the cooling water pump has a structure in which the discharge port is branched into two, there is a problem that the size of the pump itself is increased and the structure of the pump is complicated.

On the other hand, with the structure described above, although there is no problem in arranging the cooling water hose, the supply amount of the cooling water becomes uneven depending on the arrangement position of the cooling water pump depending on the cylinder, and it is difficult to form the cooling water passage itself. There are concerns. That is, although there is no problem when the cooling water pump is disposed in the V bank of the crankcase, the cooling water pump is connected to the V bank for convenience such as forming an intake port in the bank (in the case of a two-cycle engine). If it is necessary to dispose the cooling water outside, the length of the cooling water passage differs depending on the cylinder. In this case, it is sufficient to provide a water amount adjusting mechanism, but it is difficult to provide the adjusting mechanism because the cooling water passage is formed in the crankcase. Further, since the cylinder cooling water passage farther from the cooling water pump becomes longer, it is difficult to form this in the crankcase.

The present invention has been made in view of the above conventional problems,
A V-type liquid-cooled engine that can reduce the wiring space for the coolant hose, does not complicate the structure, and easily adjusts the distribution of coolant while disposing the coolant pump outside the V-bank. The purpose of the present invention is to provide a cooling device.

[Means for solving the problem]

According to the present invention, a plurality of cylinders having a liquid cooling jacket are arranged so as to form a V bank that opens forward of the vehicle and are offset in the crankshaft direction, and are mounted on the vehicle body with the crankshaft facing the vehicle width direction. In a cooling device for circulating a cooling liquid between the liquid cooling jacket and a radiator of a V-type liquid cooling engine for a motorcycle, a crankcase is provided outside the V-bank when viewed from a side of the vehicle in a crankshaft direction. A coolant pump disposed at an outer end portion in the crankshaft direction when viewed from the front of the vehicle in a direction perpendicular to the crankshaft, a discharge port of the coolant pump, and the liquid cooling jacket from the discharge port. And a liquid cooling jacket that is located farther away in the direction perpendicular to the crankshaft but shorter in the direction of the crankshaft. And a discharge port of the cooling liquid pump, and a liquid cooling jacket located at a position closer to the crankshaft but shorter in the crankshaft direction than the liquid cooling jacket from the discharge port. It is characterized in that it is connected via a coolant passage formed in the crankcase.

[Action]

According to the cooling device of the present invention, the cylinder coolant passage close to the coolant pump is formed in the crankcase,
Since only the far-side cylinder coolant passage is routed outside the crankcase, that is, since there is only one supply hose, the routing space and the routing structure are enlarged or complicated. Never.

The liquid amount can be easily adjusted by, for example, changing the hole diameter of the seal packing at the connection port between the pump and the cooling liquid passage in the crankcase or by providing a throttle valve in the cooling liquid passage arranged outside. Can be done.

Further, since only the cylinder coolant passage near the pump is formed in the crankcase, the passage formation for the cylinder on the far side described above is also difficult when forming the passage in the crankcase. No problem occurs.

The discharge port of the coolant pump disposed outside the V-bank is connected to a liquid cooling jacket located at a position far from the discharge port in the direction perpendicular to the crankshaft but short in the direction of the crankshaft. Since the discharge port of the liquid pump is connected to a liquid cooling jacket located at a position where the distance from the discharge port in the direction perpendicular to the crankshaft is short but the distance in the crankshaft direction is far from the discharge port, the cooling pump disposed outside the V-bank is The point where the length of the passage in the direction perpendicular to the axis to the liquid cooling jacket of the bank cylinder opposite to the pump is long is corrected to a shorter side as a whole due to the short length of the passage in the axis direction. On the other hand, the short passage length in the direction perpendicular to the axis to the liquid cooling jacket of the bank cylinder on the coolant pump side is due to the long passage length in the axial direction.
It is corrected to a longer side as a whole. In other words, the length of the coolant passage up to the liquid cooling jacket of each bank cylinder is equalized,
As a result, the difference in the passage resistance of the coolant passage to each bank cylinder is reduced, and the coolant supply amount is equalized.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

1 to 5 are views for explaining a cooling system for a two-stroke V-type water-cooled engine for a motorcycle according to an embodiment of the present invention. FIG. 1 is a left side view, and FIG. FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 1, FIG.
The figure is a cross-sectional plan view of a cooling water pump part, and FIG. 5 is a left side view of a motorcycle equipped with the engine of the embodiment.

In the drawing, reference numeral 1 denotes a motorcycle employing the apparatus of this embodiment, and a body frame 2 of the motorcycle is connected to a head pipe 2a by welding the front ends of a pair of left and right main frames 2b having a rectangular cross section in a rectangular shape. The rear arm brackets 2c welded to the rear end of the main frame 2b are connected to each other by a cross pipe (not shown). A radiator 31 is bridged between the lower surfaces of the left and right main frames 2b, and is supported by brackets 2d fixed to both frames 2b. The head pipe 2a supports a front fork 4 that supports the front wheel 3 at the lower end so as to be steerable left and right. The rear arm bracket 2c has a rear wheel 5 at the rear end.
Is pivotally supported up and down freely. In addition, 7 is a fuel tank and 8 is a seat.

The left and right lower portions of the left and right main frames 2b and the front portion of the head pipe 2a are surrounded by a cowling 9, in which a water-cooled two-cycle V-type two-cylinder engine 10 is suspended and supported. ing. This engine 10
Crankcase 11 divided into front and rear cases 11a and 11b
The upper cylinder 12a and the upper head 12b are stacked diagonally upward on the connection opening formed on the upper part of the front case 11a, and connected with the head bolt 14, and the lower side is connected to the connection opening formed on the lower part. The cylinder 13a and the lower head 13b are stacked diagonally downward and connected by a head bolt 14. Pistons 15a, 15b slidably inserted in the cylinders 12a, 13a are connected to connecting surfaces 16d of front and rear cases 11a, 11b of the crankcase 11 via connecting rods 16a, 16b.
It is connected to a crankshaft 17 disposed between the crankshafts 17 in the vehicle width direction.

Further, an intake port 11c is formed in the bank portion of the front case 11a, a reed valve is disposed in the intake port 11c, and a carburetor 25 is connected to the outside, and the carburetor 25 The air cleaner 27 is connected.

A cooling water pump 55 is provided at a lower portion of the rear case 11b and near the dividing surface 11d. The casing 58 of the cooling water pump 55 has a two-part structure including an inner case 56 and an outer case 57, and is fixed to a rear case 11b by fixing bolts 57c.
, And the impeller 59 is fixed by both cases.
Is formed therein. A seal packing 63b is interposed between the inner and outer cases 56 and 57, and a seal backing 63a is interposed between the inner case 56 and the rear case 11b. Further, the impeller 59 has a drive shaft
The drive shaft 59a is attached to the end of the inner case 56a.
The bearing 56b is supported by a ball bearing 61. Reference numeral 62 denotes a seal ring for sealing between the drive shaft 59a and the inner case 56.

Further, a lower discharge port 56a is formed radially outward of the impeller 59 of the inner case 56, and the discharge port 56a communicates with a lower passage 64a through an opening 63c of the seal packing 63a. I have. The lower passage 64a is connected to the crankcase 11
The lower cylinder (the distance from the pump in the direction perpendicular to the crankshaft is short but the distance in the crankshaft direction is long via a lower passage 64b formed in the front case 11a. (A cylinder disposed at the part) 13a, and communicates with a lower water-cooling jacket 13c formed at the lower part.

An upper discharge port 57b is formed in the outer case 57, and one end of a cooling water hose 65 is connected to the discharge port 57b. The hose 65 is routed upward on the side of the front case 11a, and the other end is fixed to a position near the upper cylinder of the front case 11a by a connection flange 65a, and communicates with an upper passage 64c formed in this portion. ing. The upper passage 64c is an upper cylinder (a cylinder formed at a position far from the pump in a direction perpendicular to the crankshaft but short in the crankshaft direction).
It communicates with the upper water cooling jacket 12c formed in a. The upper and lower heads 12b and 13b are connected to a radiator 31 via a return hose (not shown), and the radiator 31 is connected to a return port 60 of a cooling water pump 55 via a return hose 67. ing. This return port 60 is above the outer case
It is bolted and fixed to 57 with a seal packing 63d interposed therebetween, and communicates with the above-described impeller chamber 58a via a suction port 57a.

 Next, the operation and effect of this embodiment will be described.

In the cooling device of the present embodiment, when the engine is started and the water temperature becomes equal to or higher than a predetermined temperature, a thermo valve (not shown) is opened to start circulation of the cooling water, and the cooling water cooled in the radiator 31 is sucked into the cooling water pump 55. Is done. And the pump
A part of the cooling water pressurized by 55 flows from the lower discharge port 56a of the inner case 56 to the water cooling jacket 13c of the lower cylinder 13a through lower cooling water passages 64a and 64b formed in the crankcase 11. Supplied to The remaining cooling water is in the upper outlet 5
From 7b, cooling water hose 6 routed outside the crankcase
5, is supplied to the water cooling jacket 12c of the upper cylinder 12a through the upper cooling water passage 64c formed in the crankcase.

Here, when adjusting the cooling water amounts for the upper and lower cylinders, the seal packing 6 between the inner case 56 and the rear case 11b is required.
This is performed by replacing 3a with an opening 63c having a different size.

As described above, in the present embodiment, as the cooling water supply passage between the cooling water pump 55 and each cylinder, only the cooling water hose 65 for the upper cylinder 12a far from the pump 55 is routed to the outside. Only one water supply hose is required
Compared with the above-described structure of arranging two water supply hoses, less wiring space is required and the handling of the hoses is easier.

Further, since only the short cooling water passages 64a and 64b for the cylinder 13a on the side close to the cooling water pump 55 are formed in the crankcase of the cooling water passage, the long cooling for the cylinder on the far side described above is performed. There is no problem in forming the water passage as in the case where the water passage is also formed in the crankcase.

As for the water amount adjustment, the seal packing 63a described above is used.
Can be easily realized by exchanging. The water amount can be more easily adjusted by, for example, providing a throttle valve on the cooling water hose 65 arranged outside.

In addition, the discharge port 57b of the coolant pump 55 disposed outside the V bank is connected to the liquid cooling jacket 12c located at a portion far from the discharge port 57b in the direction perpendicular to the crankshaft but short in the crankshaft direction. Since the discharge port 56a of the cooling liquid pump 55 and the liquid cooling jacket 13c located at a position where the distance from the discharge port 56a in the direction perpendicular to the crankshaft is short but far in the direction of the crankshaft are connected, the outside of the V bank The point of the long passage length in the direction perpendicular to the axis from the coolant pump 55 disposed on the side of the pump 55 to the liquid cooling jacket 12c of the bank cylinder on the side opposite to the pump 55 is shortened as a whole by the short passage length in the axial direction. Is corrected to On the other hand, the point where the passage length in the direction perpendicular to the axis to the liquid cooling jacket 13c of the bank cylinder on the side of the coolant pump 55 is short is corrected to a longer side as a whole due to the long passage length in the axial direction. That is, the length of the coolant passage to the liquid cooling jacket of each bank cylinder is equalized. As a result, the difference in passage resistance of the coolant passage to each bank cylinder is reduced, and the amount of coolant supplied is equalized.

In the above embodiment, the case of a water-cooled two-cycle engine has been described. However, the cooling device of the present invention can be applied to an oil-cooled type or a four-cycle engine.

〔The invention's effect〕

As described above, according to the cooling device for a V-type liquid-cooled engine according to the present invention, the cylinder coolant passage on the side closer to the coolant pump is formed in the crankcase, and the cylinder coolant passage on the far side is the crankcase. Since it is routed outside the case, it is possible to prevent the wiring space for the coolant passage from being enlarged and to complicate the structure, to avoid the difficulty of making the coolant passage in the crankcase, and to adjust the fluid amount. There is an effect that can be easily realized.

The discharge port of the coolant pump disposed outside the V-bank is connected to a liquid cooling jacket located at a position far from the discharge port in the direction perpendicular to the crankshaft but short in the direction of the crankshaft. Since the discharge port of the liquid pump is connected to a liquid cooling jacket located at a position where the distance from the discharge port in the direction perpendicular to the crankshaft is short but the distance in the crankshaft direction is far from the discharge port, the cooling pump disposed outside the V-bank is The point where the length of the passage in the direction perpendicular to the axis to the liquid cooling jacket of the bank cylinder opposite to the pump is long is corrected to a shorter side as a whole due to the short length of the passage in the axis direction. On the other hand, the short passage length in the direction perpendicular to the axis to the liquid cooling jacket of the bank cylinder on the coolant pump side is due to the long passage length in the axial direction.
It is corrected to a longer side as a whole. In other words, the length of the coolant passage up to the liquid cooling jacket of each bank cylinder is equalized,
As a result, the difference in the passage resistance of the coolant passage to each bank cylinder is reduced, and the cooling water supply amount is equalized.

[Brief description of the drawings]

1 to 5 show a water-cooled type 2 according to an embodiment of the present invention.
It is a figure for explaining the cooling device of the cycle V type engine, FIG. 1 is a left side view, FIG.
FIG. 3 is a sectional view taken along line III-III of FIG. 1, FIG. 4 is a sectional plan view of a cooling water pump portion, and FIG. 4 is a left side view of a motorcycle on which the engine of the embodiment is mounted. In the figure, 10 is a V-type water-cooled engine, 11 is a crankcase, 12a is a cylinder farther from the pump, 12c and 13c are water-cooled jackets, 13a is a cylinder closer to the pump, 31 is a radiator, 55 is a cooling water pump, 64a and 64b are cooling water passages formed in the crankcase, and 65 is a cooling water hose (a cooling water passage arranged outside the crankcase).

Claims (1)

(57) [Claims] A plurality of cylinders having a liquid cooling jacket are arranged so as to form a V-bank opening forward of the vehicle and offset in a crankshaft direction, and are mounted on a vehicle body with the crankshaft directed in the vehicle width direction. In a cooling device for circulating a cooling liquid between the liquid cooling jacket and the radiator of a V-type liquid cooling engine for a motorcycle, the V-bank of the crankcase is viewed from a side of the vehicle in a crankshaft direction. A coolant pump is disposed at the outer portion and at the outer end in the crankshaft direction as viewed from the front of the vehicle in a direction perpendicular to the crankshaft, and a discharge port of the coolant pump and the liquid cooling pump from the discharge port are provided. A liquid cooling jacket, which is located at a position that is farther in the direction perpendicular to the crankshaft but shorter in the direction of the crankshaft than the jacket, is connected to a coolant hose that is routed outside the crankcase in the direction of the crankshaft. And a discharge port of the cooling liquid pump, and a liquid cooling jacket located at a position where the distance from the discharge port in the direction perpendicular to the crankshaft is shorter but the distance in the direction of the crankshaft is farther than the liquid cooling jacket. Is connected through a coolant passage formed in a crankcase.