JPH0381512A - Lubricating oil cooling device for motor cycle engine - Google Patents

Abstract

PURPOSE:To cool preponderantly and efficiently lubricating oil while supplying running wind without providing independently an oil cooler, by forming an oil groove on the inner surface of a finned cover having a cooling fin at its outside. CONSTITUTION:A cover 14 with a fin, where a cooling fin 15 is formed on the outside thereof, is provided so as to closely contacted with a joining surface 10 formed on the one side surface of a head cover 3. An intermediate part of an oil passage passing through the inside of an engine, is opened on the joining surface 10 serving as a lead-out port 11 and an introducing port 12, an oil groove 18 is formed on the inner surface of the cover 14 provided with the fin. When the cover 14 provided with the fin is closely contacted with the joining surface 10, it is respectively set so that the starting end of the oil groove 18 is connected to the lead-out port 11 and the termination of the oil groove 18 is connected to the introducing port 12. Lubricating oil pressure-supplied in order to lubricate each part, flows passing through the oil groove 18, so that the lubricating oil is thus cooled preponderantly and efficiently by heat exchanging for running wind. And it is thus possible to function as a device that an oil cooler is provided inside the engine.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a lubricating oil cooling device for an air-cooled four-cycle motorcycle engine.

(Prior art) It is well known that an internal combustion engine requires cooling, but one of the objectives for setting its cooling performance is to suppress the temperature of the lubricating oil that lubricates various parts. .

If the temperature of lubricating oil increases more than necessary, the lubricating performance will decrease and problems such as seizure will occur, so efforts are made to keep the oil temperature below a certain level.

In order to maintain the temperature of the lubricating oil at a predetermined temperature in this way, - In boat fishing, a method is adopted to improve the cooling performance of the engine itself. One way to do this is to use water cooling, and it is conceivable to use larger cooling fins while keeping the air-cooled engine. A special method is to install an oil cooler to cool the lubricating oil itself (oil cooling).

However, in the case of engines installed in motorcycles, all of these methods for enhancing the cooling performance involve enlarging the engine unit or majorly modifying the vehicle body by using a radiator or oil cooler. Since this increases cost and weight, it has been difficult to adopt it, especially for small two-wheeled motor vehicles.

(Problems to be Solved by the Invention) This invention was made in view of the above-mentioned problems, and it is possible to cool lubricating oil intensively and efficiently using the running wind without installing a separate oil cooler. The purpose of the present invention is to provide a lubricating oil cooling device for a two-wheeled motor vehicle engine.

[Structure of the invention]

(Means for Solving the Problem) In order to achieve the above object, the lubricating oil cooling device for a motorcycle engine of the present invention provides a cylinder block or a cylinder head of a four-stroke engine mounted on a motorcycle. A joint surface is formed on a part of the engine, and a finned cover with cooling fins formed on the outer surface is provided so as to be in close contact with this joint surface. Opening on the joint surface,
On the other hand, an oil groove is formed on the inner surface of the finned cover, and when the oil groove comes into close contact with the joint surface, the starting end and the above-mentioned lead-out hole are connected, and the ending end and the above-mentioned introduction hole are connected, respectively. It is what it is.

(Function) With this structure, the lubricating oil that is pumped to lubricate each part flows through the oil groove of the finned cover, and this part is close to the outer surface where the cooling fins are formed. Because of this, the lubricating oil is directly cooled at two points through heat exchange with the running wind.

Therefore, it has the same effect as an oil-cooled engine that cools lubricating oil with an oil cooler, and functions as if the oil cooler were built into the engine.

Cooling fins with almost the same cooling performance as conventional ones are sufficient, and the engine does not become larger or heavier.

(Example) DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings showing embodiments of the present invention will be explained below.

FIG. 1 is a side view of an engine unit equipped with a lubricating oil cooling device of the present invention.

That is, this engine unit is an air-cooled four-stroke engine mounted on the small two-wheeled motor vehicle shown in FIG. 11, and consists of a cylinder block 1. A large number of cooling fins 4a, 4b are provided on the surfaces of the cylinder head 2 and head cover 3.

4c is provided and is located between the leg shields 6 arranged behind the front wheels 5, and is effectively cooled by the running wind induced by the leg shields 6.

The intake 7 opens at the top of the cylinder head 2, and the exhaust 8 opens downward. 9 is a spark plug.

Next, on one side of the head cover 3, a flat joint surface 10 parallel to the traveling wind is formed by removing the cooling fins from that portion and processed to have a relatively high flatness. Joint surface↓
In the shape of No. 0, the width Wa in the front and rear directions, that is, in the direction parallel to the flow of the traveling wind, is short, and the vertical width, that is, the width Wb, in the direction perpendicular to the traveling wind, is set to be relatively long.

In the joint surface 10, an oil passage disposed inside is divided in the middle, and an outlet port ↑1 leading to the upstream side and an inlet port 12 leading to the downstream side are opened. This outlet ↑1 is arranged on the exhaust 8 side, and the inlet 12 is arranged on the intake 7 side. Also, a plurality of screw holes 13 are arranged.

A large number of cooling fins 15 are formed on the outer surface of the joint surface 10 to complement the removed cooling fins, and a finned cover 14 whose inner surface is processed to be flat is closely attached. The attachment is done by screwing a tightening bolt 17 passed through the bolt insertion hole 16 of the finned cover 14 into the screw hole 13.

As shown in FIG. 4, the finned cover 14 has a shape that is short in the front and middle and relatively long in the top and bottom widths, corresponding to the joint surface 10, and the cooling fins 15 are attached to the joint surface 10. It is set so that it is parallel to the wind when the vehicle is traveling. Further, a series of oil grooves 8 are formed on the inner surface of the finned cover 14.

The oil groove 18 has a cross-sectional shape as shown in FIG. 5, and meanderes so that its overall length is increased. And as above, the joint surface 1
0, it becomes an empty cavity, and the starting end 18a is connected to the outlet 11 of the joint surface 1.0, and the ending end 18b is connected to the inlet 12.

The above meandering pattern has dense bends on the upstream side of the traveling wind,
Roughly curved downstream.

Further, as shown in FIG. 6, on the outer periphery of the oil groove 18,
A loop-shaped O-ring groove 9 with a slightly shallow groove cross section is formed, and the O-ring is fitted into the groove to be closely attached to the joint surface 10 to seal the inside.

In this way, the lubricating oil pumped by the oil pump driven in conjunction with the crankshaft passes through the oil groove 18 during its transportation. The direction of the passage is approximately toward the exhaust 8 side (high temperature section) as shown by the arrow in Figure 4.
From there, it flows to the intake 7 side (low temperature section).

As described above, since the traveling air comes into contact with the cooling fins 15 and removes heat, the lubricating oil flowing directly behind them is thus efficiently cooled. The cooled lubricating oil is sent to each part, secondarily cooling the inside of the engine, and lubricating each part with good performance.

Moreover, the finned cover ↓ 4 is on a plane parallel to the running wind and has a long width in the direction perpendicular to the running wind, the cooling fins 15 are parallel to the running wind, and the oil groove 17 is on the upstream side of the running wind. Cooling performance can be improved more effectively by meandering tightly or by setting the flow of oil to flow from high-temperature areas to low-temperature areas.

The finned cover 14 is a separate part originally formed on the engine unit, with an oil groove provided on the joint surface, and there is almost no change in the external shape, so the engine part is larger and weighs less. A high-performance lubricating oil cooling device can be obtained without causing any problems.

Its cooling performance is comparable to that of an oil-cooled engine that uses an oil cooler, and since it can be configured as a built-in type without the need for a special oil cooler, there is no need to make extensive modifications to the vehicle body, and the number of parts can be kept to a minimum. It requires less man-hours for assembly, is provided at low cost, can be designed to be assembled into existing engines, and is superior in terms of maintenance and serviceability.

In addition, in the above embodiment, the finned cover 4 is arranged on the side of the head cover 3 of the cylinder part that tilts forward horizontally, but it is not limited to the head cover 3.
Cylinder head 2. It can be placed on the cylinder block 1 at appropriate positions on its top, bottom, left and right sides, and can be installed in the same way even if the cylinder portion is in an upright position.

Furthermore, FIGS. 7, 8, and 9 show other embodiments of the present invention.

A joint surface 20 is formed on the side surface of the head cover 3 which is horizontally tilted forward, and an intermediate cover 21 and a finned cover 14 are overlapped and closely attached to this.

The joint surface 20 has an oil outlet 22 and an oil inlet 23 and a screw hole 24, but the area is set smaller than that of the intermediate cover 21 and the finned cover 14.

The mating surface 26a inside the intermediate cover 21 has an area and shape corresponding to the joint surface 20, and an oil groove 25 is formed therein. The starting end 25a of the oil groove 25 matches the outlet 22,
The terminal end 25b is connected to the outer mating surface 26 through the lead-out through hole 27.
Opens at b. In addition, an introduction through hole 2 corresponding to the introduction port 23 is provided.
8 is placed.

29 is a bolt insertion hole corresponding to the screw hole 24, and 30 is a tapped hole.

An intermediate cover 21 is placed on the joint surface 20, and a finned cover 14 (FIG. 7) is placed on top of the joint surface 20, and the bolt insertion hole 1 is placed on top of the intermediate cover 21.
The tightening bolts 31a passed through 6 and 29 are collinear. Further, it is fastened by a fastening bolt 31b screwed into the screw hole 30. At this time, the oil groove 1 of the finned cover 14
8, the starting end 18a and the lead-out through hole 26 are connected, and the terminal end 18b and the introducing through hole 28 are connected.

In this way, lubricating oil flows from the outlet 22 of the joint surface 20 to the oil groove 25 of the intermediate cover 21 and to the finned cover 1.
The oil passes through the oil grooves 18 of No. 4 and returns to the inlet 23, during which time it is effectively cooled by the running wind that hits the cooling fins 15.

Obtaining high cooling performance for lubricating oil while keeping the engine unit compact is similar to the embodiment described above, and in this case, it is effective for use in engines where it is difficult to set a wide joint surface.

Further, by stacking a plurality of such intermediate covers, the total length of the oil groove can be increased and cooling performance can be improved.

Note that instead of the finned cover, starting ends 32a and 32b of a meandering oil pipe 32 as shown in FIG. 10 are connected to the outlet port 11.22 and the inlet port 1-223, respectively.
It is also effective to expose the oil pipe 32 directly to the running wind.

〔Effect of the invention〕

As described above, the lubricating oil cooling device for a motorcycle engine according to the present invention is provided with a lubricating oil cooling device for a motorcycle engine mounted on a joint surface formed on a cylinder block upper soil or a part of a cylinder head of a four-cycle engine mounted on a motorcycle.
A finned cover with an oil groove formed in it is closely fitted, and the lubricating oil supplied to the inside of the engine passes through this oil groove, so there is no need to install a separate oil cooler. The lubricating oil is cooled in a focused and efficient manner, making it possible to provide a compact oil-cooled engine.

[Brief explanation of drawings]

Figure 1 is a side view of a motorcycle engine equipped with a lubricating oil cooling device according to an embodiment of the present invention, and Figure 2 is Figure 1A.
FIG. 3 is an enlarged front view of the head cover as seen from the arrows, FIG. 3 is a side view taken from the C-C arrow in FIG. Figure 2 is an enlarged sectional view of the oil groove taken along the arrow C-C, and Figure 6 is Figure 2 C-C.
7 is a front view of a head cover showing another embodiment of the present invention; FIG. 8 is a side view taken along the line CC in FIG. 2; and FIG. 72 is an inner view of the intermediate cover taken along the arrow line GG in FIG. 10, a side view of an oil pipe according to another embodiment, and a first diagram is a side view showing an example of a two-wheeled motor vehicle. 1... Cylinder block, 2... Cylinder head,
3...Head cover, 10...Joint surface, 11...Oil passage outlet, 12...1 oil passage introduction, 14
...Cover with fins, 15...Cooling fins, ]8.
...Oil groove, 18a...starting end, ↑8b...terminating end,
20...Joint surface, 21...Intermediate cover, 22...
Outlet port, 23...Inlet port, 26a...Inner mating surface of intermediate cover, 26b...Outer mating surface.

Claims (1)

[Claims] 1. A joint surface is formed on a part of the cylinder block or cylinder head of a four-stroke engine mounted on a two-wheeled motor vehicle, and a finned cover with cooling fins formed on the outer surface is attached to this joint surface. At the same time, the oil passage passing through the engine is opened at the joint surface as a lead-out hole and an introduction hole, and an oil groove is formed on the inner surface of the finned cover. 1. A lubricating oil cooling device for a two-wheeled motor vehicle engine, characterized in that when the lubricating oil cooling device is in close contact with a surface, a starting end thereof is connected to the outlet hole, and a terminal end thereof is connected to the introducing hole. 2. Claim 1, characterized in that the joint surface is set long in a direction parallel to and orthogonal to the traveling wind, and the cooling fins of the finned cover are formed in a direction along the traveling wind.
The lubricating oil cooling device for a two-wheeled motor vehicle engine as described above. 3. The lubricating oil cooling device for a two-wheeled motor vehicle engine according to claim 1, wherein the oil groove has a meandering shape with a longer overall length and a higher density on the upstream side of the traveling wind. 4. The lubricating oil cooling device for a motorcycle engine according to claim 1, wherein the oil groove is arranged so that its upstream side is close to the exhaust side of the engine and its downstream side is close to the intake side. 5. One or more intermediate covers are closely stacked between the joint surface and the finned cover, and each mating surface is provided with an oil groove to form a series of oil flow passages. The lubricating oil cooling device for a two-wheeled motor vehicle engine according to claim 1.