JP2803206B2 - Lubricating oil cooling system for motorcycle engines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a lubricating oil cooling device for a motorcycle engine having four cycles of air cooling.

(Prior Art) It is well known that an engine as an internal combustion engine needs to be cooled. One of the measures for setting the cooling performance involves suppression of the temperature of lubricating oil for lubricating each part. .

If the temperature of the lubricating oil rises more than necessary, the lubricating performance deteriorates and troubles such as seizure occur. Therefore, the lubricating oil is designed to keep the oil temperature below a certain temperature.

In order to maintain the oil temperature of the lubricating oil at a predetermined temperature as described above, generally, a method of increasing the cooling performance of the engine itself is adopted. As a method thereof, water cooling is used, and it is conceivable to increase the size of the 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 mounted on motorcycles, all of these methods for enhancing cooling performance have been used to increase the size of the engine unit or the major modification of the body by using a radiator or oil cooler. Because of the increase in cost and weight, it has been difficult to adopt this method especially for small motorcycles.

(Problems to be Solved by the Invention) The present invention has been made in view of the above-described problems, and focuses and efficiently cools lubricating oil by traveling wind without installing a separate oil cooler. Automatic 2 which can
An object of the present invention is to provide a lubricating oil cooling device for a wheel engine.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above object, a lubricating oil cooling device for a motorcycle engine according to the present invention includes a cylinder block or a cylinder head of a four-cycle engine mounted on a motorcycle. A finned cover having a cooling fin formed on the outer surface thereof is provided so as to be in close contact with the joint surface, and the oil passage passing through the engine is formed in the middle of the oil passage as an outlet hole and an inlet hole. An oil groove is formed on the inner surface of the finned cover while opening to the joint surface,
The oil groove is configured such that, when the oil groove is in close contact with the joint surface, the start end and the outlet hole are connected to each other, and the terminal end is connected to the inlet hole.

(Operation) With this configuration, the lubricating oil pumped to lubricate each part flows through the oil groove of the finned cover, and this part is close to the outer surface part where the cooling fin is formed. Therefore, the lubricating oil is directly and intensively cooled by heat exchange with the traveling wind.

Therefore, the oil cooler has the same function as an oil-cooled engine that cools lubricating oil by an oil cooler, and functions as an oil cooler built in the engine.

Cooling fins having almost the same cooling performance as those conventionally set may be used, and the engine will not be increased in size and weight.

(Embodiment) A description will be given below with reference to the drawings showing an embodiment of the present invention.

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

This engine unit is an air-cooled four-stroke engine mounted on a small motorcycle shown in FIG.
This engine unit is provided with a large number of cooling fins 4a, 4b, 4c on the surfaces of a cylinder block 1, a cylinder head 2, and a head cover 3 inclined substantially horizontally, between leg shields 6 arranged behind the front wheels 5. And is effectively cooled by the traveling wind induced by the leg shield 6.

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

Next, on one side surface of the head cover 3, a flat joining surface 10 parallel to the traveling wind processed to have a relatively high flatness is formed in a form in which the cooling fins of the portion are omitted. Joint surface 10
The width of the front and rear width, that is, the width Wa in the direction parallel to the flow of the traveling wind, is short, and the vertical width, that is, the width in the direction perpendicular to the traveling wind.
Wb is set relatively long.

In the joining surface 10, an outlet 11 communicating with the upstream and an inlet 12 communicating with the downstream are opened by dividing the middle of the oil passage disposed inside. The outlet 11 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 joining surface 10 so as to complement the deleted cooling fins, and a finned cover 14 whose inner surface is flattened is closely attached. Attach it to the bolt insertion hole 16 of the finned cover 14.
Is screwed into the screw hole 13 and tightened.

The finned cover 14 has a short front-rear width and a relatively long vertical width, as shown in FIG. 4, corresponding to the joint surface 10, and the cooling fins 15 are attached to the joint surface 10. Is set to be parallel to the traveling wind when A series of oil grooves 18 are formed on the inner surface of the finned cover 14.

The oil groove 18 has the cross-sectional shape shown in FIG. 5, and meanders so as to increase the total length. And the joining surface 10 as above
When the oil flow passage is in close contact with the
It is formed as shown in the figure, and is set so that its start end 18a is connected to the outlet 11 of the joint surface 10, and its end 18b is connected to the inlet 12.

In the meandering pattern, the upstream side of the traveling wind is bent tightly and the downstream side is roughly curved.

Further, on the outer periphery of the oil groove 18, as shown in FIG.
A loop-shaped O-ring groove 19 with a slightly shallow groove cross section is formed,
An O-ring is fitted to and closely attached to the joint surface 10 to seal the inside.

Thus, the lubricating oil pumped by the oil pump driven in conjunction with the crankshaft passes through the oil groove 18 during the transportation. The direction of the passage is, as shown by the arrow in FIG.
To the intake 7 side (low-temperature portion).

As described above, the traveling wind comes in contact with the cooling fins 15 to take heat, and thus the lubricating oil flowing immediately behind the cooling fins 15 is efficiently cooled. The cooled lubricating oil is sent to each section to secondarily cool the inside of the engine and lubricate each section with high performance.

Moreover, the finned cover 14 is on a plane parallel to the traveling wind and has a large width in a direction orthogonal to the traveling wind,
The cooling performance can be improved more effectively by setting the oil flow from the high-temperature part to the low-temperature part by setting the oil groove 17 to meander from the high-temperature part to the low-temperature part. Is enhanced.

The finned cover 14 has a part originally formed on the engine unit as a separate body and is provided with an oil groove on a joint surface, and there is almost no change in external shape. Thus, a high-performance lubricating oil cooling device can be obtained.

Its cooling performance is equivalent to an oil-cooled engine using an oil cooler, and it does not require a special oil cooler.
The number of parts is kept to a minimum, the number of man-hours for assembling and the like are reduced, and it is provided at a low cost. In addition, it can be designed to be able to be assembled to an existing engine, so that it is superior in maintenance and serviceability.

In the above embodiment, the finned cover 14 is disposed on the side surface of the head cover 3 in the cylinder portion that is inclined substantially horizontally forward. However, the present invention is not limited to the head cover 3.
It can be arranged on the cylinder head 2 and the cylinder block 1 at appropriate positions on the upper, lower, left and right surfaces, and can be similarly installed even when the cylinder portion is in an upright posture.

7, 8, and 9 show another embodiment of the present invention.

A joining surface 20 is formed on the side surface of the head cover 3 that tilts forward in the horizontal direction, and the intermediate cover 21 and the finned cover 14 are overlaid and adhered to this.

An oil outlet 22 and an inlet 23 are opened in the joint surface 20, and a screw hole 24 is provided. The area is set smaller than the intermediate cover 21 and the finned cover 14.

The mating surface 26a on the inner side of the intermediate cover 21 has an area and a shape corresponding to the joint surface 20, and has a through hole 28 corresponding to the outlet 22.
Is formed. An oil groove 25 is formed in a mating surface 26a inside the intermediate cover 21, and a connection through hole 27 communicating with a mating surface 26b outside the intermediate cover 21 is used as a start end 25a of the oil groove 25 and an end 25b is introduced. It communicates with the mouth 23 side. 29 is a bolt insertion hole corresponding to the screw hole 24, and 30 is a screw hole.

The intermediate cover 21 is superimposed on the joining surface 20, and the finned cover 14 (FIG. 7) is further superimposed, and fastened together with the fastening bolts 31a passed through the bolt insertion holes 16 and 29. Further, it is fastened by a fastening bolt 31b screwed into the screw hole 30.
At this time, the leading end 18a of the oil groove 18 of the finned cover 14 is connected to the lead-out through hole 28, and the terminal end 18b is connected to the connecting through hole 27.

Thus, the lubricating oil passes from the outlet 22 of the joint surface 20 through the oil groove 25 of the intermediate cover 21 and the oil groove 18 of the finned cover 14 to return to the inlet 23, during which the cooling fins
It is cooled effectively by the traveling wind hitting 15.

Obtaining high cooling performance of the lubricating oil while keeping the engine unit compact is the same as in the above-described embodiment, and in this case, it is effective to use a wide joint surface for an engine that is difficult to set.

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

Instead of the finned cover, the meandering oil pipes 32 as shown in FIG.
It is also effective to connect the oil pipe 32 directly to the traveling wind by connecting it to the inlet 22 and the inlets 12 and 23.

〔The invention's effect〕

As described above, the lubricating oil cooling device for a motorcycle engine according to the present invention is, as described in claim 1, a cylinder block or a cylinder head of a four-cycle engine mounted on a motorcycle. The joining surface formed in part is set parallel to the flow of the running wind, and the direction perpendicular to the flow of the running wind is set longer than the parallel direction, and the cooling fins of the finned cover are set in the direction along the flow of the running wind. On the other hand, the oil groove is meandered so as to have a longer overall length, and the upstream side of the traveling wind is set to have a high density shape. Since it is located close to the cooling fins of the cover with fan, a large amount of heat is taken away by the running wind and the heat is taken away. By increasing the density of the oil grooves and making the upstream side of the running wind a high-temperature exhaust side, lubricating oil can be cooled primarily and efficiently by the running wind, eliminating the need for a separate oil cooler, so to speak Because the engine is large, it is possible to prevent the engine part from becoming larger and heavier and more reliably, without the need for extensive remodeling of the body, reducing the number of parts, simplifying the assembly man-hours, improving engine performance and reducing costs. Can be achieved.

Also, in the motorcycle oil cooling device for a motorcycle engine according to the present invention, as described in claim 2, one or more intermediate covers are overlapped and closely attached between the joint surface and the finned cover, Since oil grooves are provided on each mating surface to form a series of oil flow passages, the overall length of the oil flow passages can be increased to improve the cooling performance and improve the engine performance. Play.

[Brief description of the drawings]

FIG. 1 is a side view of a motorcycle engine provided with a lubricating oil cooling device according to an embodiment of the present invention, and FIG. 2 is FIG.
FIG. 3 is an enlarged front view of the head cover as viewed from the arrow, FIG. 3 is a side view as viewed from the direction of the arrows BB in FIG. 2, FIG. 4 is an inner view of the cover with fins as viewed from the direction of the arrows CC in FIG. 4 is an enlarged sectional view of the oil groove as viewed from the arrow D-D, FIG. 6 is an enlarged sectional view of the O-ring groove as viewed from the arrow of FIG. 4E, and FIG. 7 is a head cover showing another embodiment of the present invention. FIG. 8 is a front view of FIG.
Fig. FF is a side view as viewed in the direction of arrow, Fig. 9 is an inner view of the intermediate cover as viewed in the direction of Fig. GG, Fig. 10 is a side view of an oil pipe according to still another embodiment, and Fig. 11 is FIG. 1 is a side view showing an example of a motorcycle. 1 ... Cylinder block, 2 ... Cylinder head, 3 ...
... head cover, 10 ... joint surface, 11 ... oil passage outlet, 12 ... oil passage inlet, 14 ... finned cover,
15 ... cooling fin, 18 ... oil groove, 18a ... start end, 18b
... Terminal end, 20 ... Junction surface, 21 ... Intermediate cover, 22 ... Outlet, 23 ... Inlet, 26a ... Intermediate cover inner mating surface, 26b ... Outer mating surface.

Claims (2)

(57) [Claims] 1. A joining surface is formed on a part of a cylinder block, a cylinder head or a head cover of a four-stroke engine mounted on a motorcycle, and a finned cover having cooling fins formed on an outer surface is closely attached to the joining surface. At the same time, an oil passage passing through the inside of the engine is opened in the joint surface as an outlet hole and an introduction hole, and an oil groove is formed on the inner surface of the finned cover. When they are brought into close contact with each other, the starting end is connected to the outlet hole, and the end is connected to the inlet hole.
In the lubricating oil cooling device for a wheel engine, the joining surface is set to be parallel to the flow of the traveling wind and a direction orthogonal to the flow of the traveling wind is set to be longer than the parallel direction. On the other hand, the oil groove is meandering so as to have a longer overall length,
The upstream side of the traveling wind is set to have a high-density shape, and the oil groove has its upstream side close to the exhaust side of the engine,
A lubricating oil cooling device for a motorcycle engine, wherein a downstream side is disposed near an intake side. 2. A finned cover in which a joining surface is formed on a part of a cylinder block, a cylinder head or a head cover of a four-cycle engine mounted on a motorcycle, and a cooling fin is formed on an outer surface of the joining surface. At the same time, an oil passage passing through the inside of the engine is opened in the joint surface as an outlet hole and an introduction hole, and an oil groove is formed on the inner surface of the finned cover. When they are brought into close contact with each other, the starting end is connected to the outlet hole, and the end is connected to the inlet hole.
In a lubricating oil cooling device for a wheel engine, one or more intermediate covers are overlapped and closely adhered between the joint surface and the finned cover, and oil grooves are provided on respective mating surfaces to provide a series of oil circulation. A lubricating oil cooling device for a motorcycle engine, characterized by forming a road.