JPS58183384A - Outboard engine - Google Patents

Abstract

PURPOSE:To keep a lubricating oil at a suitable temperature and to enable the exhaust to be cooled, by providing a cooling passage between an exhaust passage and an oil containing section of an oil pan. CONSTITUTION:When an engine 16 is in operation, the lubricating oil contained in an oil containing section 59 of an oil pan 49 is circulated by operation of a lubricating oil pump 45 to lubricate sections. The exhaust of the engine 16 is discharged outside via an exhaust port, an exhaust passage 62 in the oil pan 49, an exhaust pipe 64 and an expansion chamber 29. By operation of a water pump, the surrounding water as cooling water is drawn, and is supplied to a water jacket 37 of the engine 16 via a water pipe 40 and a cooling water passage 66 of the oil pan 49. At the time of slow operation, the heat of the exhaust pssing through the passage 62 raises the lubricating oil in the section 59 to a suitable temperature through the dwelling water in the passage 66. At the time of high speed operation, the exhaust is cooled by the cooling water, while the lubricating oil is kept at a suitable temperature.

Description

[Detailed description of the invention] The present invention relates to an outboard motor.

Conventionally, outboard motors have been used in which the engine is mounted on the top of the casing, the oil pan is located approximately in the center of the engine downward, and the engine exhaust is discharged to the outside through an expansion chamber formed within the casing. It is being

However, in the above-mentioned outboard motor, the oil pan and the exhaust passage are placed close to each other in a relatively narrow area inside the casing, so the exhaust gas cannot be cooled sufficiently, and the oil tank The transmitted exhaust heat may cause the oil temperature to rise excessively.

The present invention maintains the oil in the oil pan at an appropriate temperature using cooling water pumped by a water pump, and also maintains the oil in the oil pan at an appropriate temperature.
An object of the present invention is to provide an outboard 41I that is resistant to cooling. In order to achieve the above object, the present invention mounts an engine inside a casing, arranges a first lupine on the underside of the engine, and disposes the exhaust gas of the engine. In an outboard motor that discharges cooling water from inside the casing to the outside and also supplies the engine side with cooling water that is pumped by water inside the casing, there is an exhaust vent W6t- which penetrates the oil pan approximately in the center of the oil pan.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing an outboard motor to which an internal combustion engine according to an embodiment of the present invention is applied, FIG. 2 is a sectional view showing the mounting part of FIG. 1, and FIG. 11 is a sectional view taken along line 11, and FIG. 4 is a plan view showing the oil pan taken out in the same embodiment.
Figure 5 is a sectional view taken along the line ■-■ in Figure 4, and Figure 6 is a cross-sectional view of the
It is a sectional view taken along the line ■-■ in the figure.

A casing 14 is supported on a stern plate 11 of the hull via a clamp placket 12 and a swivel racket 13. A plate-shaped intermediate member 15 is provided on the upper part of the casing 14.
An engine 16 is mounted via the . engine 1
The output of 6 is transmitted to the propeller 19 via a drive shaft 17 vertically installed in the casing 14 and a forward/reverse switching mechanism 18. , the roper 19 is rotatable.

As shown in FIGS. 2 and 3, the engine 16tlj is a water-cooled, four-stroke, two-cylinder engine, and its outline is formed by a cylinder case 20, a crankcase 21, a cylinder head 22, and a head cover 23. A pair of upper and lower cylinders are placed horizontally in the cylinder case 20, and a piston 24 is disposed in each cylinder.
Il has been.

A space defined above the piston 24 by the cylinder case 20 and the cylinder head 22 is a combustion chamber 25 . /In the part of the cylinder head 22 facing the combustion chamber 25, there is an ignition plug and an intake port 1 opened by the intake valve 26.
75A, and an exhaust boat 27A that is opened by the exhaust tank 27. The exhaust boat 27A communicates with an expansion chamber 29 in the casing 14 via an air passage 28 formed in the cylinder case 20 and an exhaust passage formed in the oil pan, which will be described later.

hffi'/Linda case 20 and crank case 2
A space defined by 1 on the back side of the piston 24 is a crank chamber 30. The crank chamber 30 includes a crankshaft 3
1 is arranged vertically, and the upper electric part of the drive shaft 17 is connected to the lower part of the crankshaft 310. The crankshaft 31 is
A crank pin 33 is provided between the two 91132, and the wide part 35 of the joint 4134 is connected to the crank pin 33. The small end of the connecting rod 34 is connected to the e x ) pin 24 by a piston pin 36 . A water jacket 37 is formed on the cylinder case 20 and the cylinder head 22, and the cooling water pumped by a water pump 38 can be circulated therethrough. The water pump 38 is arranged in the casing 14 and pumps up outside water as cooling water through a water suction pipe 39 by rotation of an impeller fixed to the middle part of the drive shaft 17. Water jacket 3 is supplied via a cooling water passage formed in the oil pan.
Pressure feed is applied to the 7 side. In addition, water jacket 3
In order to keep the cooling water temperature at the optimum temperature, there is a temperature-sensing valve that prevents the cooling water from flowing out from the water jacket 37 during startup when the cooling water temperature is below a certain temperature, and a temperature-sensing valve that prevents the cooling water from flowing out from the water jacket 37 when excessive water pressure is applied. A pressure sensitive cell is provided which opens the bypass passage of the valve.

A space defined by the front cylinder head 22 and head cover 23 is defined as a cam chamber 41. A cam shaft 42 is placed vertically in the cam chamber 41, and an intake cam 43 is mounted on the cam shaft 42.
An exhaust cam 44 is integrated, and a lubricating oil pump 45 is connected to the lower giA section. In addition, crankshaft 31Kli! A belt 4 is attached to the driving wheel 46 which is fixed to
8 is wound so that the camshaft 42 can be driven one revolution by the rotation of the crankshaft 310h.

111 An oil pan 49 is located approximately in the center of the lower surface of the intermediate member 15.
is fixed to a suspension support. The fRa oil in the oil pan 49 is pumped up by the operation of the lubricating oil pump 45 through the suction pipe 50, and the oil w! The oil around the crankshaft 31 and the camshaft 42 is cleaned through S4 through I, and after being lubricated, the oil is returned to the oil pan 49 through return oil passages 53 and 54.

Here, as shown in FIGS. 4 to 6, the oil pan 49U includes an outer cylinder part 55, an intermediate cylinder part 56, and an inner cylinder 1657.
It forms an approximately triple cylinder structure consisting of. The outer cylindrical portion 55 and the intermediate cylindrical portion 56 are connected by a bottom [58] to form an oil storage portion 59.

A plug body 60 is attached to the bottom portion 58 forming the oil storage portion 59.
A drain hole 61 is provided to which a screw can be screwed. The inner cylindrical portion 57 is located approximately at the center of the oil pipe 49 and forms an exhaust passage 62f. The exhaust passage 62 is connected to a bolt 63
It opens into the expansion chamber 29 in the casing-4 through an exhaust pipe 64 of a connecting body 63 fixed to the lower part of the first lupine 49 by A. The intermediate cylinder part 56 and the inner cylinder part 57 are
Connected by Rizo 65 and 1 year old storage section 5
A cooling water passage 66 is formed between the exhaust passage 62 and the exhaust passage 62 . The cooling water passage 66 is closed at its bottom by a connecting body 63, and is connected to the water pipe 40 via a through hole 6I and a water intake port 6B.

Note that the oil pan 49f: the above-mentioned outer cylindrical portion 55 forming
, seal members 69A and 6 are provided on the valley surfaces of the intermediate cylinder s56 and the inner cylinder part 5T with the intermediate closing material 15, respectively.
98.69G is installed.

Next, the operation of the above embodiment will be explained.

When the engine 16 is operating, the lubricating oil pump 45 is operated to circulate the lubricating oil contained in the oil storage portion 59 of the oil pan 49 to lubricate the parts requiring trough lubrication. Further, the exhaust gas from the engine 16 is discharged through the exhaust bow 27A, the exhaust passage 28, the exhaust passage 62 in the oil pan 49, the exhaust pipe 64, and the expansion chamber 29 to the yS alcohol. In addition, the operation of the water pump 38 (by which water 71 as cooling water is pumped up, the water pipe 40 and the cooling water passage 66 of the oil pan 49
Water is supplied to the water jacket 37 of the engine 16 through the water.

However, when the engine 16 is warmed up, the temperature-sensitive valve in the water jacket 37 is operated to prevent the cooling water from flowing out of the water jacket 37, and the cooling water remains in the cooling water passage w566 of the oil pump 49. As a result, the temperature of the water in the cooling water passage 66 is increased. Therefore, the exhaust heat of the exhaust gas passing through the exhaust passage 62 is transmitted to the lubricating oil in the oil storage portion 59 via the heated water in the cooling water passage @66. Quickly raise the temperature to the appropriate temperature and shorten the warm-up time.

Also, when the engine 16 is operating at high speed, the water jacket 3
7 reaches a certain temperature or higher and the temperature-sensitive valve allows the cooling water to flow out, the cooling water pumped by the water pump 38 continuously flows into the water jacket 37 via the cooling water passage 66. It is circulated. Therefore, the exhaust gas passing through the exhaust passage 62 is cooled by the cooling water passing through the cooling water passage 66, and the lubricating oil in the oil storage portion 59 is properly maintained. is maintained.

As described above, the outboard motor according to the present invention has an exhaust passageway penetrating the oil pan approximately in the center of the oil pan, and a cooling water passageway is interposed between the oil storage portion of the oil pan and the exhaust passageway. During warm-up operation after starting the engine, the lubricating oil stored in the oil storage section is raised to an appropriate temperature by exhaust heat, and during high-speed operation, the lubricating oil stored in the oil storage section is raised to an appropriate temperature by the cooling water that continuously passes through the cooling water passage. This has the effect of cooling the exhaust gas and also cooling the lubricating oil in the oil storage section, thereby making it possible to maintain the temperature of the lubricating oil at an appropriate temperature.

[Brief explanation of drawings]

Figure m1 is a side view showing an outboard motor according to an embodiment of the present invention;
Fig. 2 is a sectional view showing the main part of Fig. 1, Fig. 4 is a sectional view taken along m-mIVil in Fig. 5 is a cross-sectional view taken along the line ■-v in FIG. 4, and FIG. 6Vi is a sectional view taken along the line ■-■ in FIG. 4. 14゛ case, 16゛・° engine, 38...
Water bong! , 49... Oil pan, 59° oil storage section, 62... Exhaust passage, 66...° Cooling water passage. Agent Patent Attorney Osamu Shiokawa Figure 4 ■ Figure 5

Claims (1)

[Claims] (1) The engine is mounted on the top of the casing, and an oil pan is placed on the bottom of the engine to discharge engine exhaust gas to the outside through the inside of the casing, and to supply cooling water pumped by a water pump inside the casing to the engine. The outboard motor to be supplied is characterized in that an exhaust passage passing through the oil pan is formed approximately in the center of the oil pan, and a cooling water passage is interposed between the oil storage portion of the oil pan and the exhaust passage. outboard motor.