JPH0343115B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oil cooler applied to a motorcycle equipped with an engine having a horizontal crankshaft.

[Conventional technology]

Motorcycles with horizontal crankshafts, that is, crankshafts that are arranged to face the sides of the vehicle, are becoming more multi-cylinder and have higher output.
Consideration of cooling performance becomes even more important.

In such engines, the oil passages are designed to promote cooling of various parts of the engine, which causes the temperature of the lubricating oil itself to rise, causing deterioration of the lubricating oil.

For this reason, motorcycle engines are equipped with air-cooled oil coolers for cooling the lubricating oil.

Conventionally, this type of air-cooled oil cooler is usually installed in a down tube below the steering head pipe.

[Problem to be solved by the invention]

However, in conventional oil coolers, the front forks, front ender, etc. are located in front of the vehicle, which causes the inconvenience that the wind from the vehicle does not easily hit the oil cooler.

Further, in order to arrange the conventional oil cooler at the above-mentioned position, there were also disadvantages such as a long pipe for guiding the lubricating oil and an expensive heat radiator having many fins.

Furthermore, it is conceivable to provide an oil cooler integrally with the crankcase, but this has the disadvantage that the engine becomes larger if an oil passage with a large heat dissipation area and through which a large amount of lubricating oil passes is formed.

The present invention has been developed in view of the above circumstances, and provides good cooling performance by being well exposed to wind while traveling, increasing the flow rate of cooled lubricating oil, and simplifying the structure and reducing costs. The present invention provides an oil cooler that can achieve the following.

[Means to solve the problem]

The oil cooler for a motorcycle according to the present invention is formed by integrally providing a protrusion on the side surface of the crankcase near the side end of a horizontal crankshaft, and attaching a cover to the protrusion to form the oil cooler. In this oil cooler, an oil passage is formed by a recess provided inside the cover and a recess provided on the surface of the protrusion.

[Effect]

In the present invention, the traveling air directly hits the cover and the protrusion, and the lubricating oil passes through the oil passage formed by the recesses formed on both the inside of the cover and the surface of the crankcase.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the structure etc. of this invention will be explained in detail by the Example shown in the figure.

FIG. 1 is a side view showing a motorcycle to which the oil cooler according to the present invention is applied, and FIG. 2 is a side view of the motorcycle shown in FIG. 1.
3 is a side view of the engine with the cover removed, and FIGS. 4, 5, and 6 are a front view, a side view, and a bottom view of the cover in the present invention. In the figure, the reference numeral 1 indicates a main frame, which includes a steering head pipe 2, a down tube 3, a backstay 4, a tank rail (not shown), and the like. A rear arm 5 holds a rear wheel 6, and is pivotally supported by the main frame 1. 7 is a fuel tank installed over a tank rail (not shown); 8
is a sheet. 9 is a front fork that holds the front wheel 10, and the steering head pipe 2
It is pivoted on. 11 is a handle.

Reference numeral 20 denotes an engine mounted on the main frame 1, and a crankshaft 26, which will be described later, is arranged so as to point toward the side of the vehicle body, and serves as a horizontal crankshaft. An ignition device (not shown) is disposed at the left end of the crankshaft 26, and an oil cooler 50, which will be described later, is disposed at the right end. In this type of engine, a generator is disposed at the right end of the crankshaft 26, but in this embodiment, the generator 22 is disposed above the crankcase 21. In FIG. 1, numeral 23 is a carburetor, 24 is an air cleaner, and 25 is an exhaust pipe.

In FIG. 2, 26 is a crankshaft, 27 is a crankcase, 28 is a connecting rod, 29 is a piston, 30 is a cylinder block, and 31 is a plain bearing. The crankshaft 26 is pivotally supported by a plain bearing 31 in a vertically split crankcase 27 so as to partition each cylinder.
An outer wall 53 as a protrusion is integrally provided on the side surface of the crankcase near the side end of the crankshaft 26. 2 on the right end of the crankshaft 26
An oil passage 32 for supplying oil to the large end of each connecting rod 28 is bored in the cylinder. This oil passage 32 includes an oil passage 3 that is bored in the crankcase 27 and passes through a plain bearing 31 between both cylinders.
Lubricating oil is pumped from 3. Further, lubricating oil is pumped to the other plain bearings 31 from oil passages 33 and 34. 35 are these oil passages 3
3 and 34, and is formed in the crankcase 27 below the crankshaft 26 so as to be substantially parallel to the crankshaft 26. Note that a seal 36 is attached to the right end of the crankshaft 26 between it and the crankcase 27.

In FIG. 3, a trochoidal oil pump 37 sucks up lubricating oil from an oil pan 38 through an oil strainer 39 and pumps it to an oil filter 40. The oil passes through a cylindrical element 41 toward the center of the oil filter 40 and is filtered. This filtered lubricating oil is transferred to the oil passage 35.
The oil flows into an oil passage 42 formed parallel to the oil passageway 42, and is sent to an oil cooler 50, which will be described later.

Next, the oil cooler 50 will be explained. The oil cooler 50 includes a cover 51 attached to the side surface of the crankcase 27 near the right end of the crankshaft 26, and is formed by attaching the cover 51 to an outer wall 53. and,
In this oil cooler 50, an oil passage 52 is formed by a recess 61 provided inside the cover 51 and a recess 62 provided on the surface of the outer wall 53. That is, oil passages 35 and 42 are opened on the right side of the crankcase 27, and a cover 51 is provided to surround these oil passages 35 and 42 and the right end of the crankshaft 26.
A substantially egg-shaped outer wall 53 is integrally provided as a protruding portion with which the seams thereof abut. A partition wall 54 is formed inside the outer wall 53 and has a substantially U-shape, passing between the opening of the oil passage 35 and the opening of the oil passage 42 and sandwiching the end of the crankshaft 26. There is. This partition wall 54 does not intersect with the outer wall 53. On the other hand, the cover 51 is formed so as to be in close contact with the outer wall 53, and a partition wall 55 (FIG. 2) that is in close contact with the partition wall 54 is formed on the inner surface. As is clear from FIGS. 2 to 6, this cover 51 has a large number of substantially horizontal cooling fins 56 on its outer surface.
Moreover, uneven portions corresponding to these cooling fins 56 are formed on the inner surface. Also, cover 5
There is an O between the seam 1 and the mating surface of the outer wall 53.
A ring 57 is interposed.

In a motorcycle configured in this way,
Lubricating oil is pumped from the oil pump 37 and flows into the oil cooler 50 via the oil filter 40 and the oil passage 42. Here, the lubricating oil is
4 and flows into the partition wall 54 from between the upper end of the partition wall 54 and the outer wall 53, then descends and flows into the oil passage 35. From this oil passage 35, a portion of the lubricating oil is pumped to each plain bearing 31 and the big end of the crankshaft 26, as described above, and the remaining lubricating oil is pumped to other parts. In the process of passing through the oil passage 52 in the oil cooler 50, this lubricating oil is cooled by the traveling wind that directly hits the cooling fins 56 of the cover 51 and the outer wall 53. Moreover, at this time, the lubricating oil passes through the oil passage 52 which is made up of recesses 61 and 62 formed on both the inside of the cover 51 and the surface of the crankcase 27.

In this embodiment, since the generator 22 is disposed above the crankcase 27, the width of the engine is narrowed and the bank angle can be increased. Further, the cover 51 can be manufactured at low cost by aluminum die casting or the like.

〔Effect of the invention〕

As explained above, according to the present invention, a protrusion is integrally provided on the side surface of the crankcase near the side end of the horizontal crankshaft, and a cover is attached to the protrusion to form an oil cooler. In this oil cooler, an oil passage is formed by a recess provided inside the cover and a recess provided on the surface of the protrusion, so the airflow flows through the cover and the protrusion without being blocked by anything. Appropriate cooling occurs due to direct contact. Further, since the structure is such that lubricating oil passes through the oil passage formed by both the recesses, the amount of lubricating oil supplied to the oil cooler increases. In particular, in the case of a multi-cylinder engine, since the width of the engine increases, cooling can be performed more effectively.
In addition, by providing a protrusion on the crankcase side that the mounting surface of the oil cooler cover comes into contact with,
The surface of this protrusion can also be easily processed.
Furthermore, there is no need for an expensive radiator like in the past, and since the oil cooler can be placed close to the oil pan and close to the crankshaft, piping etc. can be shortened, reducing costs and making it more compact. It is possible to aim for Furthermore,
Since a part of the oil cooler is formed by a protrusion that is integrally provided with the crankcase, there is also the advantage that the structure can be simplified.

[Brief explanation of drawings]

FIG. 1 is a side view showing a motorcycle to which the oil cooler according to the present invention is applied, and FIG. 2 is a side view of the motorcycle shown in FIG. 1.
3 is a side view of the engine with the cover removed, and FIGS. 4, 5, and 6 are a front view, a side view, and a bottom view of the cover in the present invention. 26...Crankshaft, 27...Crankcase, 50...Oil cooler, 51...Cover, 5
2...Oil passage, 53...Protrusion, 61, 62...
recess.

Claims (1)

[Claims] 1. In a motorcycle equipped with an engine having a horizontal crankshaft, a protrusion is integrally provided on the side surface of the crankcase near the side end of the crankshaft,
An oil cooler is formed by attaching a cover to this protrusion, and an oil passage is formed in this oil cooler by a recess provided inside the cover and a recess provided on the surface of the protrusion. A motorcycle oil cooler characterized by: