JP2810902B2 - Lubrication system for 4-cycle outboard motor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a lubrication device for a four-cycle outboard motor.

[Related Art] Conventionally, a wet sump type lubrication device has been proposed as a lubrication device for a four-cycle outboard motor. In this wet sump type lubrication system, an oil pan that stores the lubricating oil after lubricating the required parts of the engine is arranged below the center of the engine body, and a lubrication pump that operates in conjunction with the engine is set up on the engine. The lubricating oil in the oil pan is connected to the lower end of the camshaft, and the lubricating oil is sucked up by the lubricating pump and supplied to a portion of the engine requiring lubrication.

[Problems to be Solved by the Invention] However, in the conventional lubricating apparatus described above, the oil pan is disposed below the center of the engine body, and the lubrication pump is located at the lower end of the camshaft. Are located below and in the side area of the lubrication pump.

This means that the suction pipe extending from the lubrication pump to the oil pan is long curved. Therefore, during storage of the outboard motor, the oil level in the suction pipe becomes the same as the oil level in the oil pan, and a long air portion is generated in the long curved suction pipe due to oil shortage. For this reason, the lubrication pump cannot suck and supply the lubricating oil immediately after the start for the restart of the engine, and there is a possibility that poor lubrication may occur.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a four-stroke outboard motor capable of supplying lubricating oil immediately after the start of an engine and constantly performing a stable lubricating action.

Means for Solving the Problems The present invention includes an oil tank for storing lubricating oil after lubricating a required portion of the engine, and supplies the lubricating oil in the oil tank to the required portion of the engine by a lubrication pump. In the lubricating device for a four-cycle outboard motor, the engine body is mounted on the upper part of the propulsion casing via a plate-shaped intermediate member, and the crankshaft standing on the cylinder block of the engine body and the camshaft standing on the cylinder head are mounted. , A lubrication pump is provided at the lower end of the camshaft, an oil tank is provided below the cylinder head and the lubrication pump, and an oil level gauge is inserted into the oil tank through an intermediate member near the cylinder head. .

[Operation] According to the present invention, there are the following effects.

Since the oil tank is provided below the lubrication pump, the suction pipe extending from the lubrication pump to the oil tank is substantially straight and short, and the installation structure is simplified.

Therefore, the length of oil shortage generated in the suction pipe during storage of the outboard motor is shortened, and lubricating oil can be supplied immediately when the engine is started.

Since the oil tank is provided below the cylinder head, the oil tank has less interference with the exhaust pipe arranged below the cylinder block, and the tank capacity can be increased.

Since the oil tank was placed below the cylinder head and the oil level gauge was passed from the intermediate member near the cylinder head to the oil tank, the oil level gauge was provided behind the outboard motor. Can be made short and vertically straight, so that even if the outboard motor is slightly inclined, there is no large shift in the oil level attachment position (oil level indication position) of the oil level gauge. If the oil level gauge is provided on the front side of the outboard motor, the oil level gauge will be inserted obliquely from the side, and the oil level attachment position of the oil level gauge will greatly deviate due to the tilting state of the outboard motor, impairing the oil level detection accuracy.

FIG. 1 is a side view schematically showing a four-cycle outboard motor, FIG. 2 is a partially broken side view showing the four-cycle internal combustion engine of FIG. 1, and FIG. 3 is a view of FIG. FIG. 4 is a sectional view showing an oil feed pump system in the pump device of FIG. 1, FIG. 5 is a sectional view showing a lubricating pump system in the pump device of FIG. 1, and FIG. FIG. 1 is a side sectional view schematically showing a four-cycle outboard motor to which the first embodiment of the present invention is applied, FIG. 7 is a sectional view showing a pump device of FIG. 6, and FIG. It is a sectional side view which shows typically the four-cycle outboard motor to which the 2nd Example was applied.

FIGS. 1 to 5 are out of the scope of the present invention.
FIGS. 7 and 8 show a first embodiment of the present invention, and FIG. 8 shows a second embodiment. FIGS. 1 to 5 will be described to show the basic structure of the outboard motor of the embodiment shown in FIGS. 6 to 8. FIG.

As shown in FIG. 1, the outboard motor 10 has a clamp bracket 12 attached to a hull 11 and a tilt shaft 12 attached to the clamp bracket 12.
The swivel bracket 14 is supported via 13 so as to be tiltable,
A propulsion casing 15 is rotatably supported on the swivel bracket 14 via a steering shaft (not shown). Propulsion casing
A four-cycle internal combustion engine 17 is mounted on an upper part of the engine 15 through a plate-shaped intermediate member 16. 10A is a cowling.
The output of the internal combustion engine 17 is transmitted to a propeller shaft 20 via a drive shaft 18 suspended in a propulsion casing 15 and a forward / reverse switching gear train 19, thereby enabling the propeller 21 to rotate forward or backward.

The internal combustion engine 17 is a four-cycle, four-cylinder internal combustion engine, as shown in FIGS. 2 and 3, in which a cylinder block 22, a crankcase 23, a cylinder head 24, and a head cover 25 form an engine main body. Four cylinders are placed horizontally in the cylinder block 22, and a piston 26 is arranged in each cylinder so as to be able to reciprocate in the horizontal direction.

The space formed by the cylinder block 22 and the cylinder head 24 on the top side of the piston 26 is a combustion substance 27.

The space formed by the cylinder block 22 and the crankcase 23 on the rear side of the piston 26 is a crank chamber 28. In the crank chamber 28, a crankshaft 29 supported by a bearing formed at a mating surface between the cylinder block 22 and the crankcase 23 is erected, and a lower end of the crankshaft 29 is provided at an upper end of the drive shaft 18. Are connected. Reference numeral 30 denotes a connecting rod connecting the piston 26 and the crankshaft 29.

A space formed by the cylinder head 24 and the head cover 25 is a cam chamber 31. A cam shaft 32 is vertically disposed in the cam chamber 31, and upper and lower ends of the cam shaft 32 are supported by the cylinder head 24. In FIG. 3, reference numeral 33 denotes an intake cam, 34 denotes an exhaust cam, and 35 denotes a rocker arm. Also, crankshaft 29
Drive wheel 36 provided at the end protruding from the crank chamber 28
A belt 38 is wound around a driven wheel 37 provided at an end protruding from the cam chamber 31 of the camshaft 32, and a crankshaft 29
The camshaft 32 makes one rotation with 1/2 rotation of the valve, and opens and closes an intake valve and an exhaust valve (not shown).

Here, since the internal combustion engine 17 constitutes a dry sump type lubrication device, as shown in FIGS. 1 to 3, an oil receiver 41 is disposed on the intermediate member 16 located below the cylinder block 22 and a crankcase is provided. An oil tank 42 is arranged laterally or forward of 23, and a pump device 43 is arranged on a lower side surface of the cylinder block 22.

Thus, the oil tank 42 of this embodiment is arranged such that the oil level of the oil tank 42 is located below and outside a lateral region of a later-described lubrication pump 54 of the pump device 43, that is, in an upper region of the lubrication pump 54. Be placed.

At this time, the oil receiver 41 is set at a position in the intermediate member 16 that is close to the crankshaft 29. An oil return path 44 extending from the crank chamber 28 to the oil receiver 41 is formed in the cylinder block 22, and an oil return path 45 extending from the cam chamber 31 to the oil receiver 41 is formed in the cylinder head 24 and the cylinder block 22. The return paths 44 and 45 meet at the upper part of the oil receiver 41 and communicate with the oil receiver 41 via a filtration and bubble separation screen 46 sandwiched between the cylinder block 22 and the intermediate member 16. That is, the lubricating oil after lubricating the respective lubrication required parts of the engine flows down the oil return paths 44 and 45 by natural fall, and collects in the oil receiver 41 via the screen 46.

The oil tank 42 has an oil inflow path 47 and an oil outflow path 48.
And a screen 49 positioned at an intermediate portion in the tank above the suction port 48A of the oil outflow passage 48. The discharge port 47A of the oil inflow path 47 is set to protrude above the oil level in the tank, and the suction port 48A
Since it is separated above A, it is effective for gas-liquid separation of the lubricating oil flowing into the oil tank 42. Also screen
49 is for filtration and foam separation, and prevents foreign substances and bubbles from flowing into the oil outlet 48 into the suction port side. The oil tank 42 has an oil inlet cap and an oil level gauge 50. Further, the oil tank 42 allows the air in the tank to flow into the cam chamber when the oil level in the tank or the tank internal pressure increases.
An air bleed pipe 51 is attached to the upper space of the oil tank 31 for escape to the space above the oil tank 42.
Check valve 52 to prevent oil leakage when the
(See FIG. 2 (B)). The valve opening pressure of the check valve 52 is set by a spring.

The pump device 43 is installed around the lower end of the crankshaft 29 as shown in FIGS. 4 and 5, and is provided with an oil feed pump 53 and a lubrication pump 54 in a two-stage stacked state in a pump body 43A. The common pump shaft 55 is driven by the rotational force of the crank shaft 29. That is, the pump shaft 55 has a pump shaft drive shaft
The driven gear 57 is fixed to the pump shaft drive shaft 56, and the driven gear 57 is engaged with a drive gear 58 provided on the crankshaft 29.

As shown in FIG. 4, the oil supply pump 53 includes a pump body 43.
A, and a suction port 60 connected to a suction path 59 provided in the cylinder block 22 is opened in the oil receiver 41,
The discharge path 61A provided in the pump body 43A is
The oil discharge passage 61B communicates with the discharge passage 61B provided on the pump 22, the oil discharge passage 61B communicates with the oil inflow passage 47 of the oil tank 42, and the rotation of the rotor 62 fixed to the pump shaft 55 causes the lubricating oil in the oil receiver 41 to be pumped. The oil is supplied to the oil tank 42. At this time, the pump body
A check valve 63 is provided in the discharge path 61A in the 43A, and lubricating oil in the oil tank 42 receives the oil in the oil receiver 41 when the outboard motor 10 is placed horizontally.
It prevents backflow to the side. The valve opening pressure of the check valve 63 is set by a spring.

As shown in FIG. 5, the lubrication pump 54 includes a pump body 43A.
The suction passage 64 provided in the cylinder block 22 communicates with the oil outflow passage 48 of the oil tank 42, and the discharge passage 65 provided in the pump body 43A is connected to the cylinder block 22 and the oil supply passage 66 provided in the cylinder head 24. Communication, pump shaft
The oil tank 42 is rotated by the rotation of the rotor 67 fixed to 55.
The lubricating oil is pressure-fed to the oil supply passage 66 and supplied to the lubrication-required parts of the engine (the bearing of the crankshaft 29, the bearing of the camshaft 32, etc.). At this time, a check valve 68 is provided in the discharge path 65 in the pump body 43A.
The lubricating oil supplied to the oil supply passage 66 is supplied to the rotor 67.
When the outboard motor 10 is placed horizontally with the lubrication pump 54 stopped with the engine stopped, the oil is prevented from flowing back to the The flow of the lubricating oil in the forward direction from the tank 42 to the oil supply path 66 is prevented.

Here, as shown in FIG. 2, the oil supply passage 66 is connected to a discharge passage 65 of the lubrication pump 54 located below the cylinder block 22 and extends upward from the connection point.
And a distribution-side oil supply passage 66B connected to the upper end of the pump-side oil supply passage 66A via an oil filter 69 and extending vertically from the oil filter 69, and further from each part of the distribution-side oil supply passage 66B. It has a branch oil supply passage 66C that branches and extends toward each lubrication required portion of the engine. Bearing part and camshaft 3 at the upper end of the crankshaft
A transfer oil supply passage 66D is arranged between the second oil holes 32A.
The lubricating oil in the uppermost branch oil supply passage 66C lubricates the crankshaft upper bearing, the camshaft upper bearing, the cam surface and the camshaft lower bearing. Pump side oil supply passage 66A to oil filter 69
Is provided with a relief valve 70 for regulating the pressure. The relief valve 70 protects the oil filter 69 by releasing the high pressure in the pump-side oil supply passage 66A to the crank chamber 28.

In addition, the amount of lubricating oil accumulated in the oil receiver 41 is reduced,
By increasing the amount of lubricating oil in the oil tank 42 by that amount, it is possible to prevent poor lubrication at the time of restart after tilting up and down. For this purpose, it is necessary to enhance the pump performance of the oil feed pump that returns the lubricating oil from the oil receiver 41 to the oil tank 42, rather than the pump performance of the lubricating pump that circulates the lubricating oil from the oil tank 42 to the oil receiver 41. In addition, the pump performance needs to be further improved because the lubricating oil on the oil receiver 41 side contains more air than the oil tank 42 side. Therefore, the rotor thickness (capacity) of the oil pump 53
Is larger than the rotor thickness (capacity) of the lubrication pump 54. The air sent to the oil tank 42 by the oil feed pump 53 increases the tank internal pressure, and the air is discharged to the air bleed pipe 51 described above.

As shown in FIG. 1, the outboard motor 10 incorporates a water pump 71 driven by a drive shaft 18 in the propulsion casing 15, and the water pump 71 driven in conjunction with the internal combustion engine 17 External water taken in from an intake 72 is supplied to a water jacket 74 of the internal combustion engine 17 through a water supply pipe 73 to cool the internal combustion engine 17 with water.

First Embodiment As shown in FIG. 6, the outboard motor 110 has a four-cycle internal combustion engine 113 mounted on an upper part of a propulsion casing 111 via an intermediate member 112, as shown in FIG. . This internal combustion engine 1
Although 13 has two cylinders, the basic configuration of each part of the engine is substantially the same as that of the internal combustion engine 17, and the same functional portions as those in the internal combustion engine 17 are denoted by the same reference numerals and description thereof is omitted. The differences between the internal combustion engine 113 and the internal combustion engine 17 are as follows.

That is, since the internal combustion engine 113 constitutes a dry sump type lubricating device, as shown in FIG. 6, an oil receiver 114 is disposed on an intermediate member 112 located below the cylinder head 24, and a rear upper end of the propulsion casing 111 is provided. The oil tank 115 is disposed in the section, and the pump device 1 is
16 are arranged.

At this time, the oil receiver 114 is installed in the intermediate member 112 at a position close to the cam shaft 32.

The oil tank 115 is installed at a position near the camshaft 32 at the upper end on the rear side of the propulsion casing 15, and has a check valve 117A attached to the intermediate member 112 and an oil inflow pipe 117.
And an oil outflow pipe 118, and an oil outflow pipe 1
A screen 119 is provided at an intermediate portion in the tank above the 18 valved suction ports 118A. Oil tank 1
15 has an oil inlet cap and oil level gauge 120. The oil level gauge 120 is inserted into the oil tank 115 through the intermediate member 112 near the cylinder head 24. Further, the oil tank 115 is provided with an air bleed pipe 121 for releasing the air in the tank to the upper space of the cam chamber 31 when the oil level rises. A check valve 122 is provided to prevent oil from leaking when the oil tank 115 falls due to the tilting of the casing 15, for example. Check valve 122
Is set by a spring. Suction port with valve 11
The valve of 8A has the same function as the check valve 68 of the first embodiment, and the side of the oil tank 115 to the side of the oil supply passage 132 when the outboard motor 10 is placed horizontally with the lubrication pump 124 stopped with the engine stopped. Prevents the flow of lubricating oil in the forward direction. The check valve 117A is of the first embodiment.
It has the same function as 63 (check valve).

6 and 7, the pump device 116 is installed around the lower end of the camshaft 32, and includes an oil feed pump 123 and a lubrication pump 124 in a two-tiered state in the pump body 116A.
A pump shaft 125 common to both is directly connected to the lower end of the cam shaft 32.

The oil feed pump 123 has a suction opening 127 of a suction passage 126 provided in the pump main body 116A opened in the oil receiver 114, and the pump main body 116A, the cover 116B, the elastic seal member 13
4 to the oil inlet pipe 1 of the oil tank 115.
The lubricating oil in the oil receiver 114 is fed by the rotation of the rotor 129 fixed to the pump shaft 125 and supplied to the oil tank 115.

At this time, a check valve (not shown) is provided in the discharge path 128 in the pump body 116A to prevent the lubricating oil in the oil tank 115 from flowing back to the oil receiver 114 when the outboard motor 110 is placed horizontally. Preventing.

The lubricating pump 124 has a suction passage 130 provided in the pump body 116A, the cover 116B,
It communicates with the oil outflow pipe 118 of 115 and the pump body
A discharge path 131 provided in 116A communicates with an oil supply path 132 provided in the cylinder block 22 and the cylinder head 24, and the pump shaft 1
The rotation of the rotor 133 fixed to 25 turns the oil tank 1
Fifteen lubricating oils are pressure-fed from the oil feed passage 132 and supplied to parts of the engine requiring lubrication (bearings of the crankshaft 29, bearings of the camshaft 32, etc.). At the bottom of oil tank 115, drain plug 115A
Is provided.

At this time, a valve (not shown) that opens when pressure is applied is provided in the discharge path 131 in the pump body 116A to prevent the lubricating oil supplied to the oil supply path 132 from flowing back to the motor 133 side. At the same time, the outboard motor 1 with the lubrication pump 124 stopped due to the engine stop is operated by the valve closing pressure set by the spring.
This prevents the flow of lubricating oil in the forward direction from the oil tank 115 to the oil feed path 132 when the 10 is placed horizontally.

In FIG. 7, an intermediate portion of the cooling water supply pipe 73 is attached to the side wall of the oil tank 115 with an adhesive 134 containing a metal such as Al, which is a good heat conductor, and lubricating oil in the oil tank 115 is provided. Is water-coolable. Also, in FIG.
135 is an exhaust pipe.

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

According to the first embodiment, the oil tank 115 is
2 and the lubrication pump 124 is connected to the camshaft 32.
At the lower end. As a result, the oil tank 115
Are arranged so that the oil level of the oil tank 115 is located below the lubrication pump 124 and outside the side region, that is, in a region substantially immediately below the lubrication pump 124.

Therefore, the oil outflow pipe 118 as a suction pipe extending from the lubrication pump 124 to the oil tank 115 is substantially straight and short. Therefore, during storage of the outboard motor 110,
The length of oil shortage generated in 18 is shortened, and lubricating oil can be supplied immediately upon starting the engine.

Therefore, according to the first embodiment, the four-cycle outboard motor
At 110, lubricating oil can be supplied immediately after starting the engine,
A stable lubricating action can always be performed.

Further, since the oil tank 115 is provided below the cylinder head 24, the oil tank 115 has less interference with the exhaust pipe 135 disposed below the cylinder block 22, and the tank capacity can be increased.

Also, since the oil tank 115 is disposed below the cylinder head 24 and the oil level gauge 120 is passed from the intermediate member 112 near the cylinder head 24 to the oil tank 115, the oil level gauge 120 is located behind the outboard motor. The oil level gauge 120 can be made short and vertically linear, so that even if the outboard motor is slightly inclined, there is no significant shift in the oil level attachment position (oil level indication position) of the oil level gauge 120. . If the oil level gauge 120 is provided on the front side of the outboard motor, it will be inserted diagonally from the side,
The oil level attachment position of the oil level gauge 120 is greatly shifted due to the tilting state of the outboard motor, thereby impairing the oil level detection accuracy.

(Second embodiment) As shown in FIG. 8, an outboard motor 140 is substantially the same as the outboard motor 110, and the same functional portions as those of the outboard motor 110 are denoted by the same reference numerals and description thereof is omitted. . This outboard motor 140 is different from the outboard motor 110 in that the oil receiver 114A is
The oil receiving pump 123 is disposed at a position sandwiched between the crankshaft 29 and the camshaft 32, and the oil supply pump 123 is connected to a suction passage 126A provided in the pump body 116A, the cylinder head 24, and the intermediate member 16 through the suction pipe 127A. Opened to 114A.

At this time, in the second embodiment, as in the first embodiment, the oil tank 115 is provided at a lower position close to the camshaft 32, and the lubrication pump 124 is installed at the lower end of the camshaft 32. did. For this reason, the oil tank 115 is arranged so as to be located substantially immediately below the lubrication pump 124, and as a result, the oil outflow pipe 118 as a suction pipe extending from the lubrication pump 124 to the oil tank 115 becomes a straight pipe and becomes shorter. Therefore, the length of oil cutoff generated in the oil outflow pipe 118 during storage of the outboard motor 140 is shortened, and lubricating oil can be supplied immediately when the engine is started. As a result, the four-cycle outboard motor 14
At 0, the lubricating oil can be supplied immediately after the start of the engine, and a stable lubricating action can always be performed.

In FIG. 8, the intermediate portion of the water supply pipe 73 is also attached to the bottom wall of the oil receiver 114A by the above-mentioned adhesive 134, so that the lubricating oil in the oil receiver 114A can be water-cooled.

Further, the present invention is not limited to the dry sump type lubricating apparatus including the oil receiver and the oil tank as in the above-described embodiments, but the return lubricating oil of the engine is received in an oil pan below the engine, and the lubricating oil is pumped. The present invention can also be applied to a wet sump type lubricating device that supplies a lubricating oil required part of an engine. That is, in the case of the wet sump type, the oil sump is arranged so as to be located substantially immediately below the lubrication pump, and the oil level of the oil sump is positioned below the lubrication pump and outside the side area. Is set.

[Effects of the Invention] As described above, according to the present invention, in a four-stroke outboard motor, lubricating oil can be supplied immediately after the start of the engine, and a stable lubricating action can always be performed.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing a four-cycle outboard motor, and FIG.
1 is a side view, partially broken away, showing the four-stroke internal combustion engine of FIG. 1, FIG. 3 is a cross-sectional view showing the four-stroke internal combustion engine of FIG. 1, and FIG. 4 is an oil feed pump in the pump device of FIG. FIG. 5 is a sectional view showing a lubricating pump system in the pump device of FIG. 1, and FIG. 6 is a schematic view showing a four-cycle outboard motor to which the first embodiment of the present invention is applied. FIG. 7 is a side sectional view showing the pump apparatus of FIG. 6, and FIG. 8 is a side sectional view schematically showing a four-cycle outboard motor to which the second embodiment of the present invention is applied. 10 outboard motor, 17 internal combustion engine, 22 cylinder block, 23 crankcase, 24 cylinder head, 29 crankshaft, 32 camshaft, 41 oil receiver, 42 …… oil tank, 43 …… pump device, 53 …… oil pump, 54 …… lubrication pump, 60 …… suction port, 110 …… outboard motor, 113 …… internal combustion engine, 114 …… oil receiver, 115 …… oil tank, 116 …… pump device, 118A …… suction port, 123 …… oil pump, 124 …… lubrication pump, 140 …… outboard motor.

Claims (1)

(57) [Claims] An oil tank for storing lubricating oil after lubricating a required portion of an engine is provided, and the lubricating oil in the oil tank is supplied to a required portion of the engine by a lubricating pump. In the lubrication device, the engine body is mounted on the upper part of the propulsion casing via a plate-shaped intermediate member, and the upright crankshaft is provided in the cylinder block of the engine body, and the upright camshaft is provided in the cylinder head. A lubricating device for a four-stroke outboard motor, comprising: a lubrication pump; an oil tank provided below the cylinder head and the lubrication pump; and an oil level gauge inserted into the oil tank through an intermediate member near the cylinder head.