JP2002242676A - Oil cooler installing structure of marine engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide oil cooler installing structure of a marine engine preventing drop in filling efficiency caused by rising of intake air temperature. SOLUTION: This oil cooler installing structure of the marine engine mounts the engine 8 on the inside of an almost water-tightly formed hull 2, supplies lubricating oil of an oil tank 40 to the engine 8 with a feed pump 41, and returns the supplied lubricating oil to the oil tank 40 with a scavenge pump 42. An oil cooler 50 is installed in a lubricating oil passage between the oil tank 40 and the scavenge pump 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil cooler arrangement for cooling lubricating oil supplied to a marine engine.

[0002]

2. Description of the Related Art For example, a water vehicle that slides on water by rotating a propulsion unit by an engine may be provided with a dry sump type lubricating oil supply device. This type of lubricating oil supply device is provided with an oil tank separately from the engine, supplies the lubricating oil of the oil tank to each lubricated portion of the engine by a feed pump, and supplies the lubricating oil supplied to the engine to a scavenge pump. In general, the oil tank is returned to the oil tank.

[0003] Since lubricating oil heated by the engine is returned to the oil tank, the lubricating oil is cooled. In this case, 2
There is a case where a lubricating oil is cooled by forming a water jacket having a heavy wall structure and flowing cooling water through the water jacket.

However, when a structure in which a water jacket is formed in the oil tank is employed, a cooling area with respect to an oil capacity is small, and sufficient cooling performance may not be obtained.

Japanese Patent No. 3096016 discloses that a straight tubular oil cooler is arranged horizontally on the engine body in the longitudinal direction of the hull, and lubricating oil fed from an oil tank by a feed pump is cooled by the oil cooler. There has been proposed a lubrication system in which the cooled lubricating oil is supplied to an engine via a main gallery, and then the lubricating oil collected in an oil reservoir is returned to the oil tank by a scavenge pump.

[0006]

However, when the oil cooler is arranged between the oil tank and the engine as described in the above-mentioned prior art, the lubricating oil warmed by the engine is returned to the oil tank. As a result, the intake air temperature may increase due to an increase in the temperature of the oil tank. Particularly, in the case of a personal watercraft such as a water vehicle, the watercraft has a watertight hull structure on the premise of capsizing, and therefore the temperature inside the hull is likely to increase, and the charging efficiency may decrease due to an increase in the intake air temperature.

[0007] Further, when the above-described straight-tube oil cooler is arranged, depending on the arrangement posture and position of the oil cooler, cooling water may remain in the oil cooler when the engine is stopped. Rust and corrosion are likely to occur in the oil cooler due to seawater or the like, and the service life may be shortened.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and is intended to prevent a decrease in charging efficiency due to an increase in intake air temperature, and to suppress the occurrence of rust and corrosion to improve the life of a marine engine. It is an object to provide an oil cooler arrangement structure.

[0009]

According to a first aspect of the present invention, an engine is mounted in a substantially watertight hull, and lubricating oil in an oil tank is supplied to the engine by a feed pump. In an oil cooler arrangement structure for a marine engine in which lubricating oil is returned to the oil tank by a scavenge pump, an oil cooler is arranged in a lubricating oil path between the oil tank and the scavenge pump.

According to a second aspect of the present invention, an engine for driving a propulsion unit is mounted in a substantially watertight hull.
In the oil cooler arrangement structure for a marine engine in which lubricating oil in an oil tank is supplied to the engine by a feed pump and the supplied lubricating oil is returned to the oil tank by a scavenge pump, the oil cooler is Is arranged such that the cooling water inlet is located higher than the water injection port of the propulsion unit.

According to a third aspect of the present invention, in the first or second aspect, the oil cooler has a lubricating oil inflow port located near a downstream side of a discharge port of the scavenge pump and is disposed above the scavenge pump. It is characterized by being.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the oil cooler has an oil pipe having an annular oil passage disposed in a cylindrical cooler body through which cooling water flows. The cooling water is characterized in that the cooling water is arranged vertically so as to flow in a substantially vertical direction.

According to a fifth aspect of the present invention, in the fourth aspect, the oil cooler is vertically arranged such that the lubricating oil flows substantially vertically.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the oil tank is mounted on a rear wall of the engine, and the oil cooler is mounted on a rear wall of the oil tank or the engine. It is characterized by having.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the cooling water supplied to the oil cooler is supplied from the oil cooler to an exhaust system via an engine.

[0016]

According to the oil cooler arrangement structure according to the first aspect of the present invention, the oil cooler is arranged in the lubricating oil path between the oil tank and the scavenge pump. Cooling is performed before returning to, so that an increase in the temperature of the oil tank can be prevented. As a result, an increase in the intake air temperature can be avoided, and deterioration in the charging efficiency can be prevented.

According to the second aspect of the present invention, since the cooling water inlet of the oil cooler is located higher than the water injection port of the propulsion unit, the cooling water in the oil cooler flows out to the water injection port when the engine is stopped. This means that water or seawater does not accumulate. As a result, rust and corrosion can be suppressed,
Life can be extended.

According to the third aspect of the present invention, since the oil cooler is disposed near the downstream side of the scavenge pump, the length of a pipe connecting the oil cooler and the scavenge pump can be shortened, and the wiring space can be reduced. And can be easily piped.
In addition, since the oil cooler is arranged above the scavenge pump, it is possible to suppress air from entering the scavenge pump at the time of capsize or landing.

According to the fourth aspect of the invention, the oil cooler is a double-cylinder type in which an oil pipe having an annular oil passage is disposed in a cylindrical cooler body through which cooling water flows. The entire outer peripheral surface and inner peripheral surface of the pipe can be cooled, the cooling area can be increased, and the cooling efficiency of the lubricating oil can be improved. It is also lighter and lighter than the conventional structure in which a water jacket is formed on the outer peripheral wall of an oil tank.
Can be compact.

Further, since the oil cooler is arranged vertically so that the cooling water flows substantially vertically, the cooling water in the oil cooler can be easily discharged when the engine is stopped, thereby preventing rust and corrosion problems. it can.

In the fifth aspect of the present invention, the oil cooler is arranged vertically so that the lubricating oil flows substantially vertically, so that the lubricating oil and the cooling water flow in the same direction.
Lubricating oil cooling efficiency can be increased.

According to the sixth aspect of the present invention, since the oil tank is mounted on the rear wall of the engine, the oil tank can be disposed by effectively utilizing an empty space around the engine. Further, since the oil cooler is attached to the periphery of the oil tank or the rear wall of the engine, in this case, the oil cooler can be disposed by effectively utilizing the empty space around the engine and the oil tank.

According to the seventh aspect of the present invention, since the cooling water is supplied from the oil cooler to the exhaust system via the engine, the cooling water having a lower temperature is supplied from the oil cooler to the engine and the exhaust system which require the cooling water having a relatively higher temperature. As a result, supercooling can be prevented and cooling efficiency can be increased.

[0024]

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

FIGS. 1 to 5 are views for explaining an oil cooler arrangement structure of a small boat engine according to an embodiment of the present invention. FIG. 1 is a plan view of a water vehicle, and FIGS. Rear view of the engine mounted on the hull,
FIG. 4 is a longitudinal sectional view of an oil cooler showing a lubricating oil path, and FIG. 5 is a transverse sectional view of the oil cooler.

In FIG. 1, reference numeral 1 denotes a water vehicle, and its hull 2 has a structure in which a lid-like deck 4 is connected to a bathtub-like hull 3 in a watertight manner. A hatch 5 can be opened and closed at the front of the deck 4, and a bar-type steering handle 6 is disposed at the rear of the hatch 5, and a saddle-type seat 7 is provided at the rear of the steering handle 6. Are detachably provided.

A vertical wall-shaped blue work 4a is formed on the left and right edges of the deck 4.
A footrest 4b extending in the front-rear direction of the hull is formed in a stepped shape inside a.

An engine 8 is mounted below the seat 7 in the hull 2 and a fuel tank (not shown) is provided in front of the engine 8. A bulkhead 12 that divides the interior of the hull 2 into an engine room 10 and a pump room 11 is provided behind the engine 8, and a propulsion unit 15 is provided in the pump room 11.

The propulsion unit 15 has an impeller shaft 17 inserted and arranged in a propulsion duct 16 having a suction port 16a opening at the bottom 2a and an injection port 16b opening at the stern 2b, and a rear end of the impeller shaft 17. Impeller 17
a is fixed.

The nozzle 16 is provided with the nozzle deflector 1
8 are connected to be able to swing left and right and up and down. The nozzle deflector 18 is operated by operating the steering handle 6 to control the hull 2.
Or to change the trim angle. The impeller shaft 17 is mounted on the bulkhead 12.
The front end of this is rotatably connected to the crankshaft 9 of the engine 8 via a coupling 19.

The water vehicle 1 includes an impeller 17
The water is sucked up from the suction port 16a by the rotation of the nozzle, and the suctioned water is pressurized and the nozzle deflector 1
Gliding on the water by jetting backward from 8.

The engine 8 is a water-cooled four-cycle two-cylinder engine, and the crankshaft 9 is disposed so as to be substantially horizontal in the longitudinal direction of the hull. The engine 8 has a structure in which a cylinder block 21 and a cylinder head 22 are stacked and fastened to a crankcase 20, and a head cover 23 is fastened to the cylinder head 22. Note that 24
Reference numerals a and 24b denote an intake cam shaft and an exhaust cam shaft, respectively.

As viewed from behind the hull 2, an intake system is provided on the left side of the engine 8, and an exhaust system is provided on the right side. In this intake system, an intake manifold 25 is connected to each intake port (not shown) of the cylinder head 22, and a carburetor 26 having a built-in throttle valve 26 a is connected to each intake manifold 25. The intake silencer 27 is connected. Each of the carburetors 26 is housed in an intake silencer 27, and a fuel injection valve 28 is mounted on each of the carburetors 26 so that an injection nozzle is directed to an intake port.
In addition, on the lower inner wall of the intake silencer 27,
a is connected.

In the exhaust system, exhaust manifolds 30 are connected to exhaust ports (not shown) of the cylinder head 22 so that the downstream ends of the exhaust manifolds 30 are joined together and the exhaust manifold is joined to the junction. It has a structure in which tubes 31 are connected. The exhaust pipe 31 is connected to the bulkhead 12.
Is connected to a water lock 32 disposed in the pump chamber 11. Further, an exhaust pipe 33 is connected to the water lock 32, and the exhaust pipe 33 extends so as to straddle above the propulsion duct 15 and opens near the injection port 16b. A cooling jacket (not shown) having a double wall structure is formed on the outer peripheral portion of each of the exhaust manifold 30 and the exhaust pipe 31.

The lubrication system of the engine 8 is of a dry sump type, and includes an oil tank 40 filled with lubricating oil.
A feed pump 41 which pressurizes the lubricating oil in the oil tank 40 and feeds the lubricating oil to the engine 8 via a main gallery 8a; And a scavenge pump 42 for returning to the position 40, and has the following structure in detail.

The main gallery 8a is formed on the bottom wall of the crankcase 20, and an oil hole for supplying lubricating oil to each lubricated portion is connected to the main gallery 8a. The oil reservoir 8b is provided in the crankcase 20.
The lubricating oil that has lubricated each lubricated part falls naturally and accumulates.

The oil tank 40 is fixedly mounted on a rear wall 8c of the engine 8. The oil tank 40 has a structure in which an air separator 45 is connected and connected to an upper portion of a tank body 44 filled with lubricating oil. The tank body 44 is connected to the feed pump 41 via an oil pipe (not shown).

In the air separator 45, a plurality of downwardly inclined separation plates 45a are arranged alternately in the vertical direction. In addition, a downstream return pipe 46 connected to the scavenge pump 42 via an oil cooler 50, which will be described later, is connected to the upper wall of the air separator 45, and a blow-by pipe 47 connected to the intake system, and A breather pipe 48 connected to a chain chamber (not shown) of the engine 8 is connected to each other.

When the lubricating oil returned by the downstream return pipe 46 alternately travels on each of the separation plates 45a and flows down, the blow-by gas and vapor contained in the lubricating oil separate and rise, and the blow-by gas passes through the blow-by pipe 47. The fuel is burned through an intake system, and the vapor is discharged to a chain chamber via a vapor pipe 48. The lubricating oil thus purified is returned to the tank body 44.

The oil cooler 5 is provided in the oil tank 40.
0 is provided. This oil cooler 50 is shown in FIG.
As shown in FIG. 5, a cylindrical oil pipe 52 having an annular oil passage 52a is provided in a cylindrical cooler main body 51 having a cooling water inlet 51a and a cooling water outlet 51b. Is inserted and fixed. A lubricating oil inlet 53 is connected to a lower end of the oil pipe 52, and a lubricating oil outlet 54 is connected to the upper end of the oil pipe 52 so as to protrude outward from the cooler body 51. Cooling water inlet 5
The cooling water flowing from 1a is discharged from the cooling water outlet 51b through the outer peripheral surface and the inner peripheral surface of the oil pipe 52.

The cooling water inlet 51a of the oil cooler 50
Is connected to a downstream cooling water supply pipe 56. The downstream cooling water supply pipe 56 extends downward from the oil cooler 50, extends rearward from the lower end thereof along the ship bottom 2 a and penetrates through the bulkhead 12, and has an upstream end 56 a downstream of the impeller 17 a of the propulsion duct 16. Communication side.
The cooling water outlet 51b is connected to the upstream cooling water supply pipe 57.
Is connected. The upstream cooling water supply pipe 57 extends upward, then bends downward in a U-shape, and is connected to the engine 8. The cooling water supplied to the engine 8 is supplied from the cylinder head 22 to the cylinder block 21 in this order, and then supplied to each of the exhaust manifolds 30 and the exhaust pipes 31, and then discharged outboard along with the exhaust gas.

The cooling water inlet 51 of the oil cooler 50
“a” is located at a higher position than the communication connection with the propulsion duct 16 which is the upstream end 56 a of the downstream-side cooling water supply pipe 56. The oil cooler 50 is arranged vertically so that the axis is substantially vertical, so that the cooling water and the lubricating oil flow vertically. Further, the oil cooler 50 is integrally attached and fixed to the left side wall 40a on the intake side of the oil tank 40.

The lubricating oil inlet 53 of the oil cooler 50
Is connected to an upstream return pipe 58. The return pipe 58 extends downward from the lubricating oil inlet 53 and is connected to the discharge port 42 a of the scavenge pump 42. Thus, the lubricating oil inlet 53 of the oil cooler 50 is connected to the discharge port 42a of the scavenge pump 42.
It is located above and near the downstream side of the discharge port 42a. The lubricating oil outlet 54 is connected to the upstream end of the downstream return pipe 46.

Next, the operation and effect of this embodiment will be described.

As shown in FIG. 4, the lubricating system of the engine 8 supplies lubricating oil in an oil tank 40 to the feed pump 4.
While being pressurized by 1, the oil is supplied to the main gallery 8a via an oil filter, and is supplied to each lubricated portion from here. The lubricating oil that has lubricated each lubricated portion flows down by natural fall and accumulates in the oil reservoir 8b. The lubricating oil accumulated in the oil sump 8b is sucked up by the scavenge pump 42, supplied to the oil pipe 52 of the oil cooler 50 via the upstream return pipe 58, and cooled therein. Next, the lubricating oil is returned to the air separator 45 via the downstream return pipe 46. Vapor and blow-by gas in the lubricating oil are separated by the air separator 45, and the purified lubricating oil is collected in the tank body 44.

On the other hand, when the impeller 17a is rotated by the operation of the engine 8, the water pressurized by the impeller 17a is supplied through the upstream cooling water supply pipe 56 into the cooler body 51 of the oil cooler 50. Here, the heat of the lubricating oil in the oil pipe 52 is absorbed. Next, the cooling water is supplied from the cooler body 51 to the engine 8 through the downstream-side cooling water supply pipe 57, and is supplied to the exhaust pipe 31 through the exhaust manifold 30.

According to the oil cooler arrangement structure of the present embodiment, since the oil cooler 50 is arranged between the oil tank 40 and the scavenge pump 42, the lubricating oil warmed by the engine 8 is cooled and returned to the oil tank 40. The temperature of the oil tank 40 can be prevented from rising. As a result, it is possible to prevent the charging efficiency from deteriorating due to an increase in the intake air temperature, and to avoid the problem of a decrease in engine output.

Since the section through which the lubricating oil whose temperature has risen flows is short from the engine 8 to the scavenge pump 42, the rise in the intake air temperature can be suppressed from this point as well. Further, since the appropriately cooled lubricating oil flows in the sections other than those described above, it is possible to prevent the flow rate shortage caused by the viscosity of the lubricating oil. That is, when the oil cooler is disposed between the oil tank and the engine, there is a problem that a section through which the cooled lubricating oil flows is short and a section through which the lubricating oil whose temperature has increased becomes long.

According to the present embodiment, the oil cooler 5
The cooling water inlet 51a of the oil cooler 50 is located higher than the upstream end 56a of the propulsion duct 16 for taking in the cooling water when the engine 8 is stopped during landing or mooring. The water flows backward through the side cooling water supply pipe 56 and flows out into the propulsion duct 16, so that water, seawater, and the like do not accumulate in the oil cooler 50. As a result, rust and corrosion can be suppressed, and the life can be extended.

Since the oil cooler 50 is disposed near the discharge port 42a of the scavenge pump 42, the length of the upstream return pipe 58 can be shortened, the wiring space can be reduced, and it is impossible. It can be installed without piping.

Since the oil cooler 50 is disposed above the scavenge pump 42, it is possible to prevent air from entering the scavenge pump 42 at the time of overturning or landing.

In this embodiment, the oil cooler 50
The oil pipe 52 having an annular oil passage 52a is inserted and arranged in a cylindrical cooler main body 51 having a cooling water inlet 51a and a cooling water outlet 51b. Cooling can be performed over the entire peripheral surface, improving the cooling efficiency of lubricating oil.
Lighter and more compact than a conventional structure in which a water jacket is formed on the outer peripheral wall of an oil tank.

Further, since the oil cooler 50 is arranged vertically so that the cooling water and the lubricating oil flow vertically,
When the engine is stopped, the cooling water in the oil cooler 50 can be easily discharged, and the problem of rust and corrosion can be prevented.
Lubricating oil and cooling water will flow in the same direction,
Lubricating oil cooling efficiency can be increased.

In the present embodiment, since the oil tank 40 is mounted on the rear wall 8c of the engine 8, the oil tank 40 can be disposed by effectively utilizing the empty space around the engine. Further, since the oil cooler 50 is mounted on the left side wall 40a on the intake side of the oil tank 40, the oil cooler 50 can be disposed by effectively utilizing the empty space around the engine, and the oil cooler 50 can be integrated with the oil tank 40. Becomes possible.

Here, in the above embodiment, the case where the oil cooler 50 is disposed on the left side wall 40a of the oil tank 40 has been described, but the present invention is not limited to this. For example, as shown in FIG. 6, the oil cooler 50 may be disposed on the rear wall 40b of the oil tank 40 or the right side wall 40c on the exhaust side, or at the corner of the rear wall 8c of the engine 8 with the oil tank 40. It may be arranged.

As shown in FIG. 7, the oil cooler 5
0 may be disposed horizontally on the upper wall or the rear wall of the oil tank 40 in the ship width direction, or the oil cooler 50 may be disposed obliquely inclined. Similar effects can be obtained.

In the present embodiment, the cooling water taken out of the propulsion duct 16 is supplied from the oil cooler 50 through the engine 8 to the exhaust manifold 30 and the exhaust pipe 31 of the exhaust system in this order. Therefore, the cooling water having a relatively high temperature is supplied to the exhaust system through the engine 8 which requires relatively high temperature, so that the supercooling can be prevented and the cooling efficiency can be improved.

In the above embodiment, a small boat of the type in which the steering wheel 6 is operated while sitting on the seat 7 arranged on the deck 4 has been described as an example, but the boat of the present invention is not limited to this. It can also be applied to a standing type that operates the steering wheel while standing on the deck, or a jet boat type with an open deck with an open deck, in other words, the engine is mounted in a substantially watertight hull It can be applied to any ship that has done this.

[Brief description of the drawings]

FIG. 1 is a plan view of a water vehicle according to an embodiment of the present invention.

FIG. 2 is a rear view of an engine mounted in the hull of the water vehicle.

FIG. 3 is a side view of an engine mounted in the hull.

FIG. 4 is a longitudinal sectional view of an oil cooler showing a lubricating oil path of the engine.

FIG. 5 is a cross-sectional view of the oil cooler.

FIG. 6 is a plan view showing an arrangement structure of an oil cooler according to another embodiment of the above embodiment.

FIG. 7 is a rear view showing an arrangement structure of an oil cooler according to another embodiment of the above embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water vehicle (ship) 2 Hull 8 Engine 8a Main gallery 8b Oil reservoir 8c Rear wall 15 Propulsion unit 30 Exhaust manifold (Exhaust system) 31 Exhaust pipe (Exhaust system) 40 Oil tank 41 Feed pump 42 Scavenge pump 42a Discharge port 50 Oil cooler 51 Cooler body 51a Cooling water inlet 51b Cooling water outlet 52 Oil pipe 52a Oil passage 53 Lubricating oil inlet 54 Lubricating oil outlet

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F01P 3/20 F01P 3/20 T

Claims (7)

[Claims] An engine is mounted in a substantially watertight hull, lubricating oil in an oil tank is supplied to the engine by a feed pump, and the supplied lubricating oil is returned to the oil tank by a scavenge pump. In the oil cooler arrangement structure of the marine engine,
An oil cooler arrangement structure for a marine engine, wherein an oil cooler is arranged in a lubricating oil path between the oil tank and the scavenge pump. 2. An engine for rotationally driving a propulsion unit is mounted in a substantially watertight hull, and lubricating oil in an oil tank is supplied to the engine by a feed pump, and the supplied lubricating oil is supplied to a scavenge pump. In the oil cooler arrangement structure for a marine engine that is returned to the oil tank, the oil cooler is arranged such that a cooling water inlet thereof is located higher than a water injection port of the propulsion unit. Oil cooler arrangement structure for marine engines. 3. The oil cooler according to claim 1, wherein the lubricating oil inlet of the oil cooler is located near a downstream side of a discharge port of the scavenge pump, and is arranged above the scavenge pump. Characteristic oil cooler arrangement structure for marine engines. 4. An oil cooler according to claim 1, wherein the oil cooler has a double-cylinder pipe structure in which an oil pipe having an annular oil passage is arranged in a cylindrical cooler body through which cooling water flows. An oil cooler arrangement structure for a marine engine, wherein the oil cooler is arranged vertically so that the cooling water flows substantially vertically. 5. An oil cooler arrangement structure for a marine engine according to claim 4, wherein said oil cooler is arranged vertically so that lubricating oil flows substantially vertically. 6. The engine according to claim 1, wherein the oil tank is mounted on a rear wall of the engine, and the oil cooler is mounted on a rear wall of the oil tank or the engine. Oil cooler arrangement structure for marine engines. 7. The oil cooler arrangement for a marine engine according to claim 1, wherein the cooling water supplied to the oil cooler is supplied from the oil cooler to an exhaust system via the engine. Construction.