JPH03134217A - Cooling device for liquid-cooled v engine - Google Patents

Abstract

PURPOSE:To make distribution of a cooling liquid amount easily adjustable while arranging space of a cooling liquid hose reduceable by arranging only a cylinder cooling liquid passage, which is located in a distant side from a cooling liquid pump, in the outer of a crankcase. CONSTITUTION:A cooling water pump 55 is arranged in the lower part of a rear case 11b further in the vicinity of a division surface 11d of a crankcase 11. The cooling water pump 55 is connected to a cooling water jacket of a lower side cylinder 13a in a side approximate to the pump 55 through a passage, formed in the crankcase 11, and to a cooling water jacket of an upper side cylinder 12a in a side distant from the pump 55 through a cooling water hose 65 arranged outside a front case 11a. Thus by arranging only the single cooling water hose 65, space and structure for arranging the hose are prevented from being spread and complicated. Also a cooling water amount can be easily adjusted by changing the seal packing hole size of a connection port, for instance, between the pump 55 and a cooling water passage in the crankcase 11.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a cooling device for a V-type liquid-cooled engine suitable for motorcycles, and in particular, it is possible to simplify the routing of coolant passages and to improve the connection between each cylinder. The present invention, which relates to a structure of a coolant passage that allows the amount of coolant to be easily adjusted, can be applied to a water-cooled or oil-cooled engine, but the following description will be made regarding a water-cooled engine.

[Conventional technology]

A cooling system for a water-cooled engine includes, for example, a cooling water pump disposed in the crankcase, and the pump is connected to a water-cooled jacket of a cylinder and a radiator through a cooling water passage, and the cooling water is passed between the water-cooled jacket and the radiator. It is configured to circulate. When this cooling device is applied to a V-type engine, since the cylinders are arranged apart from each other to form a V bank, it is necessary to branch the cooling water passage from the cooling water pump toward each cylinder. Conventionally, as a branch structure of such a cooling water passage, for example, the discharge port of the cooling water pump itself is branched into two, two cooling water hoses are connected to the branched part, and these are connected to the outside of the crankcase. ■ Structure in which the cooling water pump itself has one discharge port, and one cooling water hose connected to the discharge port is branched into two in the middle and is routed, ■ Crank case There is a structure in which a cooling water pump and each water cooling jacket are connected through two cooling water passages branched within the cooling water jacket.

[Problem that the invention seeks to solve]

In the structures of (1) and (2) above, two cooling water hoses are routed outside the crankcase, which increases the space for routing the hoses and complicates the routing of the hoses. Moreover, in the case of (2), since the discharge port of the cooling water pump is structured to be branched into two, there is a problem that the pump itself becomes large and the structure of the pump becomes complicated.

On the other hand, with the structure (■), although there are no problems with the cooling water hose routing, depending on the placement position of the cooling water pump, the amount of cooling water supplied may be uneven depending on the cylinder, and it may be difficult to form the cooling water passage itself. There are concerns that. In other words, there is no problem if the cooling water pump is installed in the bank of the crankcase, but for reasons such as forming an intake port in the bank (in the case of a 2-stroke engine), the cooling water pump is installed in the bank. If the cylinders have to be placed outside, the length of the cooling water passages differs depending on the cylinder, resulting in a problem of non-uniform water flow. In this case, it would be sufficient to provide a water amount adjustment mechanism, but since the cooling water passage is formed within the crankcase, it is difficult to provide an adjustment mechanism. Furthermore, since the cooling water passage for the cylinders on the side far from the cooling water pump is correspondingly longer, it is difficult to form this passage inside the crankcase.

The present invention has been made in view of the above-mentioned conventional problems, and it is possible to reduce the wiring space for the coolant hose, without complicating the structure (also, by arranging the coolant pump outside the V-bank). At the same time, it is easy to adjust the distribution of the coolant amount.
The purpose is to provide a cooling system for type liquid-cooled engines.

[Means for solving problems]

The present invention relates to a cooling device for circulating a coolant between a liquid cooling jacket and a radiator of a V-type liquid cooled engine in which a plurality of cylinders each having a liquid cooling jacket are arranged to form a V bank. A coolant pump is disposed on the outer side of the V bank, and the coolant pump and the liquid cooling jacket of the cylinder near the pump are connected via a coolant passage formed in the crankcase, and the cooling It is characterized in that the liquid pump and the liquid cooling jacket of the cylinder on the side far from the pump are connected via a coolant passage routed outside the crankcase.

[Effect]

According to the cooling device of the present invention, the coolant passage for the cylinder on the side closer to the coolant pump is formed in the crankcase, and only the coolant passage for the cylinder on the far side is routed outside the crankcase. In other words, since there is only one supply hose, the wiring space and the wiring structure will not be expanded or complicated.

In addition, the liquid level can be easily adjusted by, for example, changing the hole diameter of the seal gasket at the connection port between the pump and the coolant passage in the crankcase, or by installing a throttle valve in the coolant passage routed outside. can be done.

In addition, since only the coolant passage for the cylinder on the side closer to the pump is formed in the crankcase, it is difficult to No problems arise.

〔Example〕

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

1 to 5 are diagrams for explaining a cooling system for a two-cycle V-type water-cooled engine for a motorcycle according to an embodiment of the present invention, in which FIG. 1 is a left side view and FIG. 2 is a partial view. 3 is a cross-sectional view taken along the line ■-■ in FIG. 1, FIG. 4 is a cross-sectional plan view of the cooling water pump portion, and FIG. 5 is a left side view of the motorcycle equipped with the engine of this embodiment. It is a diagram.

In the figure, reference numeral 1 denotes a motorcycle in which the embodiment device is adopted, and its body frame 2 has a head pipe 2a connected to the front ends of a pair of left and right main frames 2b each having a rectangular cross section by welding. 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 mounted between the lower surfaces of the left and right main frames 2b, and is supported by brackets 2d fixed to both frames 2b. Further, the head pipe 2a has a lower end that pivotally supports a front fork 4 that pivotally supports the front wheel 3 so that it can be steered left and right, and the rear arm bracket 2a
The rear end of C supports a rear arm 6 which supports a rear wheel 5 so as to be able to swing up and down. Note that 7 is a fuel tank and 8 is a seat.

The lower left and right parts of the left and right main frames 2b and the front part of the hend pipe 2a are surrounded by a cowling 9, and a water-cooled two-stroke V-type two-cylinder engine 10 is suspended and supported within the cowling 9. There is. This engine 1
0 is a crankcase 1) which is divided into two parts, a front case 1) and a rear case 1)3. The lower cylinder 13a is stacked facing toward each other and connected with the head bolt 14, and the lower cylinder 13a is connected to the connection opening formed at the bottom.
, and the hood 13b is stacked diagonally downward on the lower side, and is connected with a head bolt 14. A piston 1 slidably inserted into each of the cylinders 12a and 13a.
5a and 15b are connected via connecting rods 16a and 16b to a crankshaft 17 disposed in the vehicle width direction between the dividing surfaces 1)d of the front and rear cases Ila and llb of the crankcase 1). There is.

In addition, there is an intake port 1) in the bank part of the front case lla.
C is formed, a board valve is disposed inside the intake port 1)c, and a carburetor 25 is connected to the outside.
5 is connected to an air cleaner 27.

and the lower part and dividing surface lid of the rear case llb.
A cooling water pump 55 is disposed near the. The casing 58 of this cooling water pump 55 has a two-part structure consisting of an inner case 56 and an outer case 57.
7c is fastened together to the rear case Ilb, and both cases form an impeller chamber 58a that accommodates the impeller 59. A seal packing 63b is provided between the inner and outer cases 56 and 57, and a seal gasket 63b is provided between the inner case 56 and the rear case l.
Seal packings 63a are interposed between each of them. Further, the impeller 59 is attached to the tip of a drive shaft 59a, and the drive shaft 59a is attached to the inner case 56.
The bearing portion 56b is pivotally supported by a ball bearing 61. Note that 62 indicates the drive shaft 59a and the inner case 56.
This is a seal ring that seals between the

Further, a lower discharge port 56a is formed in the inner case 56 radially outward of the impeller 59;
a communicates with the lower passage 64a via the opening 63c of the seal packing 63a.

This lower passage 64a is formed in the rear case Ilb of the crankcase 1), and is connected to the lower cylinder (the cylinder near the pump) via the lower passage 64b formed in the front case Ila. ) 13a is connected to a lower water cooling jacket 13C formed in the lower water cooling jacket 13a.

Further, 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 lla, and the other end is connected to the connecting flange 65.
It is fixed at a position near the upper cylinder of the front case 1)a by a, and communicates with an upper passage 64c formed in this part. This upper passage 64C communicates with an upper water-cooled jacket 12C formed within the upper cylinder 12a. 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 the cooling water pump 55 via a return hose 67. ing. The return port 60 is bolted to the outer case 57 with a seal packing 63d in between, and communicates with the impeller chamber 58a via the suction port 57a.

Next, the effects of this embodiment will be explained.

In the cooling system of this embodiment, when the engine is started and the water temperature reaches a predetermined temperature or higher, a thermovalve (not shown) opens, cooling water circulation is started, and the cooling water cooled in the radiator 3I is sucked into the cooling water pump 55. be done. A part of the cooling water pressurized by the pump 55 is transferred to the inner case 5.
6 is supplied to the water cooling jacket 13c of the lower cylinder 13a through lower cooling water passages 64a and 64b formed in the crankcase 1).

The remaining cooling water is supplied from the upper discharge port 57b to a cooling water hose 65 routed outside the crankcase. The water is supplied to the water cooling jacket 12C of the upper cylinder 12a through an upper cooling water passage 64C formed in the crankcase.

Here, if you want to adjust the amount of cooling water for the upper and lower cylinders,
This is done by replacing the seal gasket 63a between the inner case 56 and the rear case Ilb with one having a different size opening 63c.

In this embodiment, only the cooling water hose 65 for the upper cylinder 12a on the side far from the pump 55 is routed outside as the cooling water supply path between the cooling water pump 55 and each cylinder. Only one water supply hose is required to be routed, compared to the above-mentioned structure in which two water supply hoses are routed.
It requires less space for wiring, and the hoses can be easily routed.

Furthermore, since only the short cooling water passages 64a and 64b for the cylinder 13a on the side closer to the cooling water pump 55 are formed in the crankcase among the cooling water passages, the long cooling water passages 64a and 64b for the cylinders on the far side are formed in the crankcase. There is no problem in forming the water passage, unlike when the water passage is also formed in the crankcase.

In addition, regarding water volume adjustment, the above-mentioned seal packing 63a
This can be easily achieved by replacing. Note that this water amount 1) can be more easily determined, for example, by providing a throttle valve on the cooling water hose 65 routed outside.

In the above embodiment, the case of a water-cooled two-stroke engine was explained, but the cooling device of the present invention can also be applied to an oil-cooled engine.
Of course, it can also be applied to a 4-cycle engine.

〔Effect of the invention〕

As described above, according to the cooling device for a V-type liquid-cooled engine according to the present invention, the coolant passage for the cylinder on the side closer to the coolant pump is formed in the crankcase, and the coolant passage for the cylinder on the far side is formed in the crankcase. Since the cables are routed outside the case, it is possible to prevent the expansion of the wiring space for the coolant passage and the complication of the structure, and also avoid the difficulty of creating the coolant passage inside the crankcase. There are effects that can be easily achieved.

[Brief explanation of the drawing]

1 to 5 show a water-cooled type 2 according to an embodiment of the present invention.
1 is a left side view, FIG. 2 is a partially sectional left side view, and FIG.
3 is a sectional view taken along the line m--■ in FIG. 1, FIG. 4 is a sectional plan view of the cooling water pump portion, and FIG. 4 is a left side view of the motorcycle on which the engine of this embodiment is mounted. In the figure, 10 is a ■ type water-cooled engine, 1) is a crankcase, 12a is a cylinder far from the pump, 12c, 1
3c is a water cooling jacket, 13a is a cylinder near the pump, 31 is a radiator, 55 is a cooling water pump, 64a, 6
4b is a cooling water passage formed in the crankcase, 65
is a cooling water hose (cooling water passage routed outside the crankcase).

Claims (1)

[Claims] (1) In a cooling system that circulates coolant between the liquid cooling jacket and the radiator of a V-type liquid-cooled engine in which a plurality of cylinders each having a liquid-cooling jacket are arranged to form a V-bank, A coolant pump is disposed on the outer side of the V bank, and the coolant pump and the liquid cooling jacket of the cylinder near the pump are connected via a coolant passage formed in the crankcase, and the coolant A cooling device for a V-type liquid-cooled engine, characterized in that a pump and a liquid-cooled jacket of a cylinder on a side far from the pump are connected via a coolant passage routed outside a crankcase.