JP2000297620A - Lubrication structure of vertical engine - Google Patents

Abstract

(57) [Problem] To provide a lubricating structure for a vertical engine capable of pumping lubricating oil with a simple structure. Kind Code: A1 In a vertical engine in which a crankshaft is placed vertically in an engine housing, a camshaft is arranged on the side of the crankshaft, and both shafts are provided with timing gears provided on the respective shafts. On the other hand, an oil pan 19 is disposed below the engine housing 14, and a cover plate 38 is provided on a joint surface between the engine housing 14 and the oil pan 19, and the two timing gears 3 are provided in the oil pan 19.
A liquid-tight gear chamber 37 for accommodating the gear chambers 3 and 34 is formed.
The positive pressure generated in the oil pan 7 is fed into the oil pan 19 and the lubricating oil in the oil pan 19 is fed into the engine 3 by pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a lubricating structure for a vertical engine.

[0002]

2. Description of the Related Art A droplet type is generally used as a lubrication method for a small OHV engine. The splash type lubrication method is, for example, to provide a splash member such as a slinger (wing) at a large end of a connecting rod, and to fly the lubricating oil to each part of the engine while scooping up the lubricating oil of an oil pan with the slinger. The cost is low because the structure is simpler than the oil pump pressure lubrication method such as the trochoid pump used for the engine.

[0003]

However, the splash type lubrication method is effective only when the crankshaft is in a horizontal state, and in the case of a vertical engine in which the crankshaft is arranged vertically like an outboard motor. In this case, it is necessary to provide a rotating body having a splashing member as a separate part, resulting in an increase in cost and weight.

Further, the lubrication method of the splash type is inferior to the lubrication method of the oil pump pressurization type in that the lubrication method is affected by the inclination of the engine and the oil is not smoothly circulated during acceleration and deceleration.

The present invention has been made in view of the above circumstances, and has as its object to provide a lubricating structure for a vertical engine capable of feeding lubricating oil with a simple structure.

[0006]

According to the present invention, there is provided a lubricating structure for a vertical engine in which a crankshaft is vertically disposed in an engine housing as described in claim 1 in order to solve the above-mentioned problems. In the above, a camshaft is arranged on the side of the crankshaft and both shafts are connected via a timing gear provided on each shaft, while an oil pan is arranged below the engine housing, and A cover plate is provided on a joint surface with the oil pan to form a liquid-tight gear chamber for accommodating the timing gears in the oil pan, and a positive pressure generated in the gear chamber by rotation of the timing gears. So that the lubricating oil in the oil pan is pumped into the engine. Are those that form.

In order to solve the above-mentioned problem, it is preferable that the gear chamber is used as an oil pump chamber and both timing gears are used as gear pumps to collect and pump lubricating oil. It was done.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a right side view showing an example of an outboard motor provided with a vertical engine according to the present invention. As shown in FIG. 1, the outboard motor 1 has a box-shaped engine cover 2 at the top, and a vertical (vertical) engine 3 therein.
Is stored. A steering handle 4 extends forward from the front of the engine cover 2 (the right side in FIG. 1), and a throttle grip 5 for adjusting the engine output is provided at its tip.

A shaft housing 6 is provided below the engine cover 2.
The gear case 7 is provided at the lower part of the vehicle. A propeller shaft 8 is rotatably supported inside the gear case 7, and a propeller 9 is provided at a rear end thereof.

In the engine 3, a crankshaft 10 is provided vertically (vertically) so as to be directed substantially vertically. A drive shaft 11 connected to the lower end of the crankshaft 10 extends downward in the shaft housing 6, and the lower end of the drive shaft 11 is connected to the propeller shaft 8 via a bevel gear 12. The output of the engine 3 is transmitted to the propeller shaft 8 via the drive shaft 11 and the bevel gear 12, and rotates the propeller 9.

The upper portion of the shaft housing 6 is rotatably supported by a rotation support portion 13b of a clamp bracket 13, and the clamp bracket 13 is fixed to a transom of a ship (not shown). That is, the outboard motor 1 is rotatable about 360 ° with respect to the boat, and the steering of the boat can be performed by swinging the steering handle 4 in the horizontal direction to change the direction of the entire outboard motor 1. It is configured as follows.

The engine cover 2 is, for example, vertically splittable, and comprises a lower cover 2a fixed to the lower part of the engine, and an upper cover 2b detachably mounted on the lower cover 2a. The steering handle 4 is provided integrally with the lower cover 2a.

FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3, and FIG. 5 is a view taken in the direction of the arrow V in FIG. As shown in FIGS. 1 to 3, the engine 3 used in the present embodiment is, for example, 4
This is a single-cylinder engine provided with a cycle OHV type valve operating mechanism. The engine housing 14 includes a front (right side in the figure) crankcase 15 and a rear (left side in the figure) cylinder block 16.

A cylindrical cylinder 17 is formed integrally with the cylinder block 16 and extends rearward (leftward in the figure) in a direction perpendicular to the crankshaft 10. A cylinder head 18 is provided at the rear end of the cylinder 17. . An oil pan 19 storing lubricating oil therein is provided below the engine housing 14 including the crankcase 15 and the cylinder block 16, and a fuel tank 20 is disposed above the cylinder head 18.

A cylinder bore 17 is provided inside the cylinder 17.
a, and a combustion chamber 21 is formed in the cylinder head 18 so as to match the cylinder bore 17a.
The ignition plug 22 is connected to the combustion chamber 21 from outside.

In the crankshaft 10, a pair of webs 10a are formed in the middle part thereof at a distance from each other in the axial direction, and a crankpin 10b is eccentrically provided therebetween. In addition, the crankshaft 10 has both outer portions of the web 10 a supported by the engine housing 14 by bearings 23.

On the other hand, a piston 24 is slidably inserted into the cylinder bore 17a. The piston pin 24a of the piston 24 and the crankpin 10 of the crankshaft 10 are connected by a connecting rod 25, whereby the reciprocating motion of the piston 24 in the cylinder bore 17a is converted into the rotational motion of the crankshaft 10. At the upper end of the crankshaft 10, a flywheel magneto device 26 for power generation and a rope recoil type engine starting device 27 are provided.

An intake port 28 and an exhaust port 29 connected to the combustion chamber 21 are formed in the cylinder head 18.
Further, an intake valve 30 and an exhaust valve 31 for opening and closing both ports 28 and 29 are arranged in the cylinder head 18.

As shown in FIGS. 2 and 4, a camshaft 32 is arranged on the side of the crankshaft 10 in parallel with the crankshaft 10. A timing drive gear 33 is provided below the crankshaft 10 in the oil pan 19.
Is provided integrally or integrally with the crankshaft 10, and a timing driven gear 34 is provided integrally or integrally with the camshaft 32 below the camshaft 32 in the oil pan 19.
The rotational force of the crankshaft 10 is transmitted to the camshaft 32 by the meshing and operative connection of the four.

A cam 32a is provided on the camshaft 32, and the cam 32 rotates when the camshaft 32 rotates.
The profile a moves the push rod 35 disposed on the side of the cylinder 17 in the axial direction, and rocks the rocker arm 36 provided in the cylinder head 18 so as to be swingable as shown in FIG. . The rocking arm 36 swings the cylinder head 18.
The intake / exhaust valves 30 and 31 inside are opened and closed.

In the oil pan 19, both timing gears 3 are provided.
A gear chamber 37 that accommodates the gears 3 and 34 is formed. Further, a plate-shaped cover plate 38 is provided on a joint surface between the lower surface of the engine housing 14 and the upper surface of the oil pan 19, and the gear chamber 37 can be functioned as an oil pump chamber by keeping the gear chamber 37 liquid-tight.

The gear chamber 37 has two timing gears 33, 34.
The two timing gears 3 have a planar shape along the outer circumference of
Oil chambers 39a and 39b are formed on both sides of the meshing portions of the members 3 and 34, respectively. Of these oil chambers 39a and 39b, the cover plate 38 above the first oil chamber 39a formed on one side with a line 40 connecting the centers of both timing gears 33 and 34 formed inside the engine housing 14. Crank chamber 4
1 and an oil recovery port 4 that communicates with the inside of the first oil chamber 39a.
2 is formed, and a wall of the gear chamber 37 on the side of the second oil chamber 39b formed on the opposite side of the line 40 is provided with an oil that communicates the inside of the second oil chamber 39b with the inside of the oil pan 19. The discharge port 43 is formed. In addition, both oil chambers 39a, 39b
The first oil chamber 39a is disposed at a position where both timing gears 33 and 34 become negative pressure when the timing gears 33 and 34 rotate, and the second oil chamber 39b is disposed at a position where both timing gears 33 and 34 become positive pressure.

A check valve 44 is provided on a lower side surface of the oil pan 19, and an oil supply hose 45 extending from the check valve 44 is connected to, for example, the crankshaft 10.
Is connected to an oil supply passage 46 extending toward the bearing 23 supporting the upper portion of the oil supply passage.

Next, the operation of the present embodiment will be described.

When the crankshaft 10 rotates, its rotational force is transmitted to the camshaft 32 via the timing drive gear 33 and the timing driven gear 34. These timing gears 33 and 34 are structurally the same as a well-known gear pump used for a pressure-feeding oil pump. Therefore, the gear chamber 37 in which the timing gears 33 and 34 are housed is an oil pump chamber, and the gear chamber 3
If an oil recovery port 42 and an oil discharge port 43 are provided in 7, the timing gears 33 and 34 also function as a gear pump.

That is, when both the timing gears 33 and 34 rotate, the first oil chamber 3 is set in advance so that the pressure becomes negative.
9a, the lubricating oil in the crank chamber 41 is sucked from the oil recovery port 42, and the second oil chamber 3 is set to have a positive pressure in advance.
The oil is discharged from the oil discharge port 43 into the oil pan 19 through 9b. While the engine 3 is running, both timing gears 3
The lubricating oil in the oil pan 19 is guided to the support bearing 23 on the upper part of the crankshaft 10 via the check valve 44 so that the oil pan 19 always keeps the positive pressure in the oil pan 19. Bearing 23 and connecting rod 2 that support crankshaft 10
5. Lubricate each part of the engine 3, such as the piston 24.

A part of the lubricating oil in the crank chamber 41 accumulates at the bottom of the crank chamber 41, and the remaining lubricating oil reaches the inside of the cylinder head 18 by using the primary compression action associated with the reciprocating motion of the piston 24, and reaches the rocker arm 36. After lubricating the valve train components, such as the valve train, the engine returns to the crank chamber 41. Then, the lubricating oil returned to the inside of the crank chamber 41 is returned to the oil collecting port 4 again.
2 is guided into the gear chamber 37 and circulates through the engine 3.

Since the timing gears 33 and 34 can function as gear pumps, the lubricating oil can be pumped to each part of the engine 3 without increasing the number of parts and costs. The lubrication performance is improved as compared with.

The two timing gears 3 are set in the gear chamber 37.
Since the lubricating oil in the engine 3 is collected by the negative pressure generated by the lubricating oil 3, 34, the efficiency of collecting the lubricating oil is improved, so that the required amount of the lubricating oil is minimized. As a result, the oil pan 19 can be reduced in size, and the entire engine 3 can also be reduced in size and weight.

Further, by always keeping the inside of the oil pan 19 at a positive pressure, the position of the lubricating oil discharge portion (check valve 44) provided in the oil pan 19 can be set freely.

In the above-described embodiment, an example is shown in which the timing gears 33 and 34 for transmitting the rotational force of the crankshaft 10 to the camshaft 32 are used as gear pumps. However, in the case of an engine having a balancer, details will be described. Although not shown, the balancer shaft is generally arranged on the side of the crankshaft, and both shafts are connected by a pair of balancer gears. Thus, as in the present invention, the storage chamber of the balancer gear is an oil pump chamber, and the balancer gear is a gear pump. It is also possible to use it, and it has the same effect as the present invention.

Further, in the above-described embodiment, the engine 3 used for the outboard motor 1 has been described. However, if the crankshaft is arranged vertically in the engine,
It is also applicable to general-purpose engines for lawnmowers and generators.

[0034]

As described above, according to the lubricating structure for a vertical engine according to the present invention, in an engine in which a crankshaft is installed vertically in an engine housing, a camshaft is arranged on the side of the crankshaft. Connecting the two shafts via timing gears provided on the respective shafts, disposing an oil pan below the engine housing, and providing a cover plate on a joint surface between the engine housing and the oil pan, A liquid-tight gear chamber accommodating the timing gears is formed in the oil pan, and a positive pressure generated in the gear chamber by rotation of the timing gears is sent into the oil pan to lubricate the oil pan. Since the oil is pumped into the engine, lubrication performance can be improved. .

The gear chamber is an oil pump chamber,
Since the lubricating oil can be collected and pumped using the two timing gears as a gear pump, the required amount of lubricating oil is minimized and the size of the oil pan can be reduced.

[Brief description of the drawings]

FIG. 1 is a right side view of an outboard motor showing one embodiment of a lubrication structure for a vertical engine according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a view taken in the direction of the arrow V in FIG. 3;

[Explanation of symbols]

 Reference Signs List 1 outboard motor 3 vertical engine 10 crankshaft 14 engine housing 19 oil pan 32 camshaft 33 timing drive gear (timing gear) 34 timing driven gear (timing gear) 37 gear chamber 38 cover plate 39a first oil chamber 39b second oil Chamber 42 Oil recovery port 43 Oil discharge port 44 Check valve

Claims (2)

[Claims] In a vertical engine in which a crankshaft is placed vertically in an engine housing, a camshaft 32 is arranged on a side of the crankshaft 10 and both shafts 10 and 32 are provided on the respective shafts 10 and 32. The oil pan 1 is connected to the lower portion of the engine housing 14 through the timing gears 33 and 34.
9, a cover plate 38 is provided on the joint surface between the engine housing 14 and the oil pan 19, and a liquid-tight gear chamber 37 that accommodates the timing gears 33 and 34 is formed in the oil pan 19. At the same time, the positive pressure generated in the gear chamber 37 by the rotation of the timing gears 33 and 34 is sent into the oil pan 19 and the lubricating oil in the oil pan 19 is fed into the engine 3. A lubricating structure for a vertical engine. 2. The gear chamber 37 is an oil pump chamber,
2. A lubricating oil recovery and pumping operation using the timing gears 33 and 34 as a gear pump.
The lubrication structure of the vertical engine described.