JPH0213703Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cooling water jacket device for an outboard motor.

Conventionally, an air-cooled engine is provided above an extension case provided in the outboard motor body, with an oil pan provided at the bottom of the engine seated on the upper end of the case, and the engine is mounted on one side of the case. There are known outboard motors that are provided with an exhaust duct that guides exhaust gas, and in which a drive shaft that guides the output of the engine is inserted into a space on the other side of the case. There is a problem in that the heat tends to cause the extension case to heat up and even the oil pan to heat up.

The object of the present invention is to provide a cooling water jacket device that can protect both the extension case and the oil pan from heat damage. An air-cooled engine 4 is provided with an oil pan 3 provided at the bottom of the engine 4 seated on the upper end of the case 2, and an exhaust duct 5 for guiding the exhaust from the engine 4 on one side of the case 2. A drive shaft 7 for guiding the output of the engine 4 is inserted into the space 6 on the other side in the case 2, and a drive shaft 7 is inserted between the oil pan 3 and the exhaust duct 5 in the case 2. A cooling water jacket 8 is provided.

As shown in FIG. 1, the extension case 2 includes a column portion 13 extending downward, and the drive shaft 7 is inserted through the case 2 into the column portion 13.
A propeller 11 driven by the drive shaft 7 is inserted into the lower part of the column part 13, and a water pump 10 is provided slightly above the propeller 11.

As clearly shown in FIGS. 1 and 2, the exhaust duct 5 is formed on the inner surface of one side wall of the extension case 2 so as to extend upward from a substantially middle position of the case 2, and has an upper portion 5a bent laterally. Case 2
An external connection port 5b is formed at the tip of the upper part 5a, and an exhaust pipe 14 connected to the exhaust port of the engine 4 is connected to this, and the exhaust gas is passed through the duct 5. The gas was introduced into the column section 13 and discharged into the water through an exhaust outlet 12 formed at the bottom of the column section 13.

As clearly shown in FIGS. 2 and 3, the jacket 8 is integrally formed with the extension case 2 and has a shape that covers the upper portion 5a of the exhaust duct 5 from its upper surface to both sides. Top surface 8
The oil pan 3 was seated on the upper end of the case 2 so as to cover the upper surface 8a, and was bolted to the upper end of the case 2. The jacket 8 has an inlet 8b on its side surface and an outlet 8c on its bottom, and is connected to the water pump 10 via the inlet 8b and a cooling water tube 9 to introduce cooling water. The outlet 8c is formed in the bottom surface in the form of a cast mold, through which water is discharged into the lower end of the exhaust duct 5.

To explain its operation, as the water pump 10 operates, the cooling water introduced into the jacket 8 through the cooling water tube 9 comes into contact with the lower surface of the oil pan 3 at its upper surface 8a and cools it.
After cooling the lower exhaust duct 5, the outlet 8
It is discharged into the lower end of the duct 5 through the pipe c, mixes with the exhaust gas, and falls while cooling it.

In this way, according to the present invention, the cooling water jacket 8 is provided in the extension case 2, interposed between the oil pan 3 of the engine 4 and the exhaust duct 5 that guides the exhaust gas from the engine 4.
By cooling both the oil pan 3 and the exhaust duct 5, a cooling effect can be performed over a wide range including cooling of the oil in the oil pan 3, and a temperature rise in the case 2 can be prevented and the case 2 can be cooled. This has the effect of eliminating heat damage to the case 2 and increasing the durability of the parts surrounding the case 2.

[Brief explanation of the drawing]

FIG. 1 is a partially cut-away side view of an example of an outboard motor equipped with the present device, FIG. 2 is a sectional view taken along the line ``--'', and FIG. 3 is a sectional view taken along the line ``--''. 1...outboard motor body, 2...extension case, 3...oil pan, 4...engine, 5...
...exhaust duct, 6...space, 7...drive shaft, 8...cooling water jacket.

Claims (1)

[Scope of utility model registration request] An air-cooled engine 4 is provided above an extension case 2 provided in the outboard motor main body 1, and an oil pan 3 provided at the bottom of the engine 4 is seated on the upper end of the case 2. An exhaust duct 5 is provided on one side to guide the exhaust gas from the engine 4, and a space 6 on the other side inside the case 2 is provided with an exhaust duct 5 for guiding the exhaust gas from the engine 4.
A cooling water jacket device for an outboard motor, which is inserted through a drive shaft 7 that guides the output of an outboard motor, and comprises a cooling water jacket 8 interposed between the oil pan 3 and the exhaust duct 5 in the case 2. .