JPS5844206A - 4-cycle internal-combustion engine - Google Patents

Abstract

PURPOSE:To lubricate and cool each part of an internal-combustion engine through a single of oil passage, in the captioned internal combustion engine used for an outboard engine and the like, by supplying lubricating oil, flowing in a main oil passage, partially to a crankshaft through sub-oil passages. CONSTITUTION:Lubricating oil is led by a main oil passage 56 to the side of a cylinder head 28, and the oil, immediately after led out from an oil pump 44, is once led to the side of a crankshaft 15, here branching sub-oil passages 60, 61, leading the lubricating oil to the crankshaft 15, are provided in a portion positioned in the vicinity of this crankshaft 15. Lubricating oil, flowing into these sub-oil passages 60, 61, is distributed into a gap 21 of a bush 18 to lubricate upper and lower bearing supported parts of the crankshaft 15. On the other hand, the lubricating oil, divided flowing in an upper passage 58, is forcibly fed in this upper passage 58 to an end part in the side of a cam shaft 37, and then led into a bearing part 39, to lubricate an upper end bearing supported part of the cam shaft 37.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a four-stroke internal combustion engine used, for example, in an outboard motor.

It is widely known that the lubrication structure of two- and four-stroke internal combustion engines uses a forced-feeding splash type.This lubrication structure pumps up the lubricating oil in the cylinder block or cylinder head C oil pan. An oil pump is provided, and the lubricating oil pumped by the oil pump (2) is supplied to the camshaft by a first oil passage (2) extending toward the camshaft. A second oil passage branching from the starting end C2 near the pump and extending toward the crankshaft side is provided, and this second oil passage ≦2 2 is used to control lubricating oil delivered from the oil pump. It has 4 sides so that a part of it is supplied to the crankshaft.

However, as described above, in the structure in which the second oil passage is branched off at the starting end of the first oil passage, that is, the oil passage led out from the oil pump, the oil,
The lubricating oil sent out from the second oil passage is not evenly distributed between the first oil passage and the second oil passage, resulting in less inflow resistance! 1. Tendency to flow more into the oil passage side I:
There is a risk that the amount of oil supplied to the legs and crankshaft may be insufficient. As a countermeasure for this, it is possible to increase the amount of oil sent out from the oil pump so that a predetermined amount of lubricating oil is distributed throughout the second oil passage.
Of course, this would require an oil pump with a large discharge volume.

There is a point a that requires a large amount of lubricating oil.

The present invention was made based on these circumstances, and
The purpose of this is to be able to reliably lubricate and cool each part of the internal combustion engine, such as the camshaft and crankshaft, with a single oil path, and to simplify and downsize the vsm, as well as to This is an attempt to provide a four-stroke internal combustion engine that does not require an oil pump and requires a small amount of oil.

That is, 1. the present invention achieves the above object.

When the lubricating oil pumped by the oil pump is led to the crankshaft side and then fed to the camshaft side through the main oil passage that extends toward the camshaft side,
Both C:% An auxiliary oil passage is branched and provided in a part of this main oil passage located near the crankshaft,
The auxiliary oil passage supplies a portion of the lubricating oil flowing through the main oil passage to the crankshaft.

An embodiment of the present invention will be described below based on drawings in which an outboard motor 62 is applied.

In the figure, reference numeral 1 indicates an outboard motor, which is attached via a bracket 2 to the transom of a boat (not shown).

This outboard motor 1 is constructed by attaching a cowling 6 to the upper end of a casing 5 formed by connecting an upper casing J and a lower casing 4 made of aluminum alloy. C2 accommodates the four-stroke engine 1 according to the present invention.

The engine 1 of the present embodiment is a water-cooled four-stroke two-cylinder engine, and is rigidly mounted on an exhaust guide 8 formed with two layers so as to close an upper end opening 4 of a casing 5.

This engine 7 is installed in a cylinder block 9 (21 pairs of cylinders 10m, 10b are arranged vertically in parallel, each cylinder 10 layer, 10b is arranged so that its cylinder axis runs in the direction of the front fireflies). Sleeves 11.11 are attached to the inner surfaces of the 0% cylinders 10m and 10b, and pistons 12.12 are accommodated in these sleeves 11.11. A crankcase 13 is attached, and the inside of this crankcase 12 forms a crank chamber 14 connected to a cylinder 10m"10b. (written in notes).

The upper and lower ends of the crankshaft 15 are connected to bearing portions 16m and 16b provided at the abutting portions of the crankcase 13 and the cylinder block 9 through oil seals I'j/, lfl and pushers 18 and 18, respectively. supported. The inside 6 of the crankshaft 1j is one end or the crankshaft 15.
The upper and lower ends of the crank bin 19, 19 are opened on the same surface, and oil passages 2o and 2o are formed through them, and the other end is opened on the same surface of the crank bin 19, 19. ,
The pushers 1g and 11 are opposed to gaps 21, 21 along the local direction -2 provided in the axially intermediate portions of the pushers 1g and Ill. The crank pin 1m, III of the crankshaft 15 is slidably fitted into the big end 2J of the connecting rod 2222, and these connecting rods 2, 2゜22
connects the piston 12.11 and the crankshaft 15. In this way, the upper and lower ends of the rank shaft 15 are the bearing parts Ja
m, 16b, and is led out to the outside.This upper end leading part area 2 is where the drive gear 24 is fixed (44=), and the lower end leading part 62 is the casing 5 yen. The upper end of the drive shaft 2j inserted in the vertical direction (2
It is designed to rotate.

Further, a cylinder head 28 is attached to the rear end surface of the cylinder block, and this cylinder head 28 has combustion chambers J#a, Jjl of each cylinder 10m, 10b≦2.
It has b. fkg1 for each combustion chamber 29m, 2mb
1 port 30 and exhaust port 31 are opened adjacent to each other.

These suction and exhaust ports JO and SL are connected to the air pulp J2 and exhaust pulp JJ4: so that they can be opened and closed. The intake pulp 32 and the exhaust pulp 3S are connected to a pulp spring; t4. s4t: Therefore, the direction ζ in which the suction and exhaust ports 30 and 31 are closed is biased.

A head cover (-35) is bolted to the rear end of the cylinder head 28, and a camshaft housing chamber 3 is located between the rear surface of the cylinder head 28 and the head cover 3s.
6 is formed.

In this camshaft storage chamber J6, one camshaft sr is arranged vertically along the vertical direction, and this camshaft S1 takes in air through rocker arms as and ax. The end portion of the camshaft 31 is rotatably supported via a C oil seal 40 in a bearing portion 3# at the top of the cylinder head 28. The book is passed through this bearing part 39 to the outside (two parts are led out),
A driven gear 41 is fixed to this upper end lead-out portion. A drive belt 42 is stretched between the driven gear 41 and the drive gear 24, and therefore the camshaft 31 is rotationally driven by the crankshaft IJ6. Further, a bearing portion 3 is provided at the bottom of the cylinder head 28.
#(=A pump mounting hole J is provided oppositely, and an oil pump 44 is integrally installed here. 45 is the pump housing, and the cylinder head 284: Bolt 46 is tightened. As shown in FIG.

A bearing part 4 is attached to the protruding tip of the pump housing 45.
F is recessed, bearing part 42 yen 1;

A lower end portion of the camshaft zr is rotatably inserted into the camshaft zr. Therefore, the lower end of the camshaft 1r is pivotally supported by the pump housing 45.

Further, the pump housing 45 has an interior (=pump chamber 4# and an oil passage 49), and a pump cover 50 is fastened to the bottom surface of the pump housing 45 together with the bolts 46.

The pump cover j0 is brought into close contact with the lower surface of the pump housing 45 to constitute a seat plate of the pump chamber 48, and is provided with a passage 51 that communicates the pump chamber 48 and the oil passage 49. Inside the pump M4J is a camshaft 31.
Lower end C: The connected shaft 5j is inserted, and an impeller 5J is attached to the insertion portion of the shaft 52. In addition, a suction passage 54 is connected to the oil passage 9 of the pump I housing 45. The suction passage 54 between the cylinder head 2# and the cylinder block 9
It is provided across the lower combustion chamber 2# and extends below the lower cylinder 10m in the front-rear direction 1: and communicates at the abutment surface between the cylinder block t and the cylinder head 21. has been done. One end of this suction passage 54 is connected to the oil passage 49 in the cylinder head 28 (second place), and the other end is located inside the cylinder 1g 9 (two places) on the lower surface of the cylinder block 9, and the other end is connected to the bottom surface of the cylinder block 9. It is opened in the abutting surface with the guide 8.

Further, the pump housing 45 is provided with a discharge port 55), one end of which opens on the upper surface of the pump chamber 48, and an upper bearing portion 41 (
=Opened.

The other end opening of this discharge port 55 (= is the main oil passage 6
6 are connected. The main oil passage 56 includes a lower passage 11 which is arranged in parallel with the suction passage 54 and extends inside the cylinder head 28 and the cylinder bush 9 from the camshaft 31 side to the crankshaft 15 side 6: and the cylinder head 21. and upper combustion chamber 2 inside cylinder 1gtsuk9.
gb (= camshaft 7 located above the upper cylinder 10b and from the crankshaft 15 side) JF@O2 and an upper passage 51 extending in the front-rear direction.

A crank shaft 15 connects these upper passage s1 and lower passage 51.
and a communication path 59 extending vertically within the cylinder block 9 and communicated with each other in the vicinity of the cylinder block 9 . That is, the upper passage 58 and the lower passage 57 are bent at a substantially right angle toward the end on the crankshaft 15 side or one side of the cylinder block 9, and are extended to a portion outside the cylinders 10m and 10b. Therefore, the communication passage 59 is located on the side of the cylinders 10m and 10b(1).

Therefore, the main oil passage 56 has a generally U-shaped side surface that extends toward the camshaft 31 after being led toward the crankshaft 15 side. The starting end of the main oil passage 56, that is, the cylinder head 28 of the lower passage 57
One end located inside the cylinder head 28 of the terminal end of the main oil passage 56 and the upper passage 68 communicates with the discharge port 55, and one end located inside the cylinder head 28 of the upper passage 68 is connected to a bearing portion into which the upper end portion of the camshaft 11 is inserted. 39 circular surfaces (opened.

In addition, at the bent portions of the lower passage 51 and the upper vaginal passage 58,
Side oil passages 60 and 61 are provided in a branched manner at the husband. These auxiliary oil passages 60, 61 are connected to the cylinder dog tube 9.
The inner part extends toward the crankshaft 15 side, and the tips thereof are opened at the inner surfaces of the bearing parts 16m and 16b.

The opening of this auxiliary oil passage 60.61 is opposed to the gap 21.21 between the pushers Lis and J7. Furthermore, an oil inflow passage 62 is branched and connected to the gauging portion between the upper passage 58 and the communication passage 59, and is used to adjust the pressure of the lubricating oil pumped through the main oil passage 56 to a constant value. An oil pressure switch 61' is installed.

Further, on the lower surface of the cylinder block 9, a combustion Wi 7 is provided.
9 m, ? An exhaust outlet 64 leading to the exhaust boat 31.31 #b is opened, and a recess 65 is provided adjacent to this exhaust outlet 64c.

The bottom front part 62 of this recess 65 has communication ports 1jfj, 6g leading to the crank chamber 14 opened therein, and is a contact surface with the cylinder head side side wall "rk" of the recess 65 and the cylinder valve vagina 9 of the cylinder head I8. Oil outflow holes 6r and 68 are opened in the lower part □ to face each other and communicate the inside of the recess 65 and the lower part of the camshaft housing chamber 36.Therefore, the recess 65 is connected to the crank chamber 14 and the camshaft housing chamber 36. It communicates with the chamber 36 and is arranged.

On the other hand, on the lower surface of the exhaust guide 8.

As shown in mxowJ, an oil pan 6# having a cylindrical shape with a bottom is fixed to a suspension support, and this oil pan 69yen62 stores lubricating oil.

The exhaust guide 8 (the second is the oil return hole 10 that communicates the recess 65 with the inside of the oil pan 69, the suction hole 11 that is opposed to the opening of the suction passage 54, and the exhaust lower 2 that leads to the exhaust outlet 64). The suction hole 71 is equipped with the suction port body 7j,
A suction pipe 74 for sucking up the lubricating oil from the oil pan 6 is connected to this suction port body 13 (second part).A vertical oil strainer containing wire is attached to the tip of the suction pipe 14. Also, approximately at the center of oil pan d'9,
An exhaust pipe passage 7r is defined by a partition wall 76 from inside this oil pan 6# and is provided along the vertical direction (two directions), and the front end portion of the partition wall 76 is continuous with the inner surface I of the oil pan 69. The upper end opening of this exhaust pipe penetration path 11 is aligned with the exhaust port 12 of the exhaust guide 8, and an exhaust pipe 75 is attached to the lower opening of the exhaust lower 2.Exhaust pipe 75 is loosely inserted through the exhaust pipe passage 11, and its lower end is led out into the upper casing 3, so that the inside of the upper casing 3 constitutes an exhaust expansion chamber 81. oil pan 6
A cooling water passage 19 is formed vertically through the part communicating with the gate g, and the upper end of this cooling water passage 79 is connected to the water jacket 78 of the engine 1. (=, ``The lower end is the water tube 82
It is connected to a quarter inlet 80 on the side of the lower casing 4 through a water pump 8J.

　　　　　4 However, the 4 lubricating oil in oil pan 6#.

Each part of the engine 7 is lubricated through the route described below (2).In other words, when the camshaft 31 is rotated with the start of the engine R, the impeller 53 is rotated integrally, so that the pump chamber 48 Negative pressure, oil pan 69
Inside 6 = Reserved lubricating oil is drawn into the pump chamber 4 #Pg (:@) via the suction pipe 74, suction passage 54, etc. This suctioned oil is gradually increased in pressure and sent from the discharge port 55 to the bearing. 41 and into the lower passage 51 of the main oil passage 5#.Then, this lubricating oil lubricates the lower end shaft support of the camshaft S1 and the lower passage iH of the camshaft S1.
q flows through the end neck on the crankshaft side, and then through the communication path 5#
It flows into the circle and is guided into the side passage W&51 via this communication path 59. Therefore, the lubricating oil that is pressure-fed is divided into two flows: one flows directly into the lower passage Jr at the branching point between the lower passage 51 and the auxiliary oil passage 60, and the other flows into the auxiliary oil passage 60. i The flow is divided into two parts, and the connection part C between the one continuous passage am and the upper passage 58;
The flow flowing into the upper passage 58 yen and the inside of the auxiliary oil passage 61 (
= The inflow flow and the flow divided into 6 parts. The lubricating oil that has flowed into the auxiliary oil passage 60.61 is transferred to the bush 18.
The clamping shaft 15 is distributed within the gap 21.11 of 18.
Lubricate the upper and lower shaft branches of the

Furthermore, this lubricating oil is supplied to the oil passage 20 in the crankshaft]5.
, 10 to the circumferential surface C of the crank pin 19° 19, and the crank pin III.

After lubricating and cooling the sliding contact parts between 19 and the big ends zs and zz, the oil is ejected from the clearance between them or from the oil jet holes of the big ends: ts and xs, and the inner wall of the sleeve JJ, 77 and the piston 77.73. Back side etc. 1
: Sprayed and cooled smoothly. After this, 7g
8. The lubricating oil falls from the lower part I of the crank chamber 14, and flows from this to the communication hole 66.6g, the recess 66, and the oil return hole 70.
The oil pan ILg is returned via .

On the other hand, the lubricating oil diverted into the upper passage 58 is forced into the upper passage II to the end on the camshaft side, and then guided to the bearing part 19 to lubricate the upper end shaft support of the camshaft 31. do. The lubricating oil led to the bearing part 3942 is transmitted through the clearance between the bearing part 39 and the camshaft 31 to the camshaft housing chamber 36.
It is ejected in a circular direction and is sprayed onto the inner surfaces of the cylinder head 28 and head cover 86 to cool them down and absorb 12% of the exhaust pulp. Valve mechanism (
: Adheres to lubricate and cool these. Thereafter, the lubricating oil falls to the lower part of the camshaft housing chamber 36, and from there it is returned to the oil pan via the oil outflow hole 61, 611% recess 65, and oil return hole 70.

According to the above configuration 1, the cylinder head 28 side = the main oil passage si for guiding the lubricating oil is connected to the crankshaft 1 immediately after the oil pump 44 is also led out.
．． 5 side 6 = Leading, near the crankshaft 1i - 1 located part 6 2, crankshaft IJ6; Since the auxiliary oil passage 60° 61 that leads the lubricating oil has been branched, each part in the engine 1 is continuous. Lubricating and cooling can be achieved through a single oil path, and there is no need to provide many long oil paths in the cylinder block 9 and head 28.
The lubricating oil distribution path is greatly simplified, and the number of man-hours required for machining the cylinder block 9 and the head 2# is reduced, reducing costs, and the engine 1 as a whole can be downsized.

Moreover, since the auxiliary oil passages 60.61 are branched in the vicinity of the crankshaft Jj, the auxiliary oil passages 60.
Since the overall length of 61 is extremely short and there is little inflow resistance, there is no fear that the amount of oil introduced into the crankshaft IS will be insufficient, and reliable lubrication and cooling can be obtained. In this case, since lubricating oil flows into the auxiliary oil passage ε0.61 yen, there is no need to use a special pump with a large discharge amount, and therefore the oil pump 44 has a small shape; a compact one. This has advantages such as being more convenient in reducing the size and weight of the engine 1.

In the above embodiment, a two-cylinder engine is used, but the same effect can be applied to a single-cylinder engine or a multi-cylinder engine with three or more cylinders.

Further, the internal combustion engine according to the present invention is for an outboard motor (not limited to two, therefore, the camshaft and crankshaft may also be of a vertical type (not specified, but may be of a horizontal type).

Of course, the oil pump is also driven by a camshaft (C2), but it is also possible to drive it by a crankshaft, for example. The lubricating oil is supplied to the camshaft side C2 through a main oil passage which is led to the crankshaft A and then extends towards the camshaft side. 4 = The located partial oil passage is provided with two branched auxiliary oil passages, and a part of the lubricating oil flowing through the above-mentioned main oil passage is supplied to the crankshaft. According to this article, it is possible to lubricate and cool each part of an internal combustion engine with a single oil path.
There is no need to provide many long and complicated oil passages in the cylinder block or head, and the lubricating oil distribution path is greatly simplified, making it ideal for internal combustion engines! It is possible to reduce the number of processing steps during LLI manufacturing, thereby reducing costs, and also to achieve a reduction in size and weight of the entire internal combustion engine. However, since the total length of the four auxiliary oil passages is short, there is little oil inflow resistance, and there is no shortage of oil introduced to the crankshaft side.

Since a sufficient amount of lubricating oil flows into the auxiliary oil passage C2, there is no need to use a special oil pump with a large discharge volume; therefore, a compact oil pump may be sufficient.

This has excellent effects such as being more convenient for downsizing the entire internal combustion engine.

[Brief Description of the Drawings] The drawings show an embodiment of the invention, in which Figure 1 is a side view of the outboard motor, Figure 2 is a cross-sectional view of the Tsumagai engine, and Figure 3 is a cross-sectional view of the engine orthogonal to the camshaft. 4 is a plan view of the cylinder block, FIG. 5 is a plan view of the cylinder head, FIG. 6 is a sectional view taken along line VI-Ml in FIG. 4, and FIG. 1 to 6 are cross-sectional views taken along the line VI-VA, and FIG. 8 is a bottom view of the cylinder block and cylinder head. a
Figure 9 is a bottom view of the cylinder block and cylinder head installed on the exhaust guide C: when viewed from the casing side, Figure 10 is a sectional view of the Atsunoken casing, and Figure 11 is taken along the line Xl-■ in Figure 10. FIG. 15...Crankshaft, 28...Cylinder head°. 37...Camshaft, 44...Oil pump. 56...Main oil passage, 60.61...Auxiliary oil passage, 69...Oil pan. Applicant's agent Patent attorney Takehiko E Takehiko No. 6 - Figure 7 Figure 11 Figure 69 Procedural amendment November 6, 1981 Commissioner of the Patent Office Shima 1) Haruki Tono 1, Patent application for indication of the case 1982- 142663 No. 2, Title of the invention 4, Internal combustion engine 3, Relationship with the case of the person making the amendment Patent applicant Sanshin Kogyo Co., Ltd. 4, f, Yu), (and others 8) 6, Power of attorney to be amended, details Letter, Drawing 7, @Correct Contents (1) Amend the power of attorney as shown in the attached sheet.

Claims (1)

[Claims] In a 4-cycle circular twist engine equipped with a cylinder head and a camshaft, an oil pump is provided to suck up lubricating oil from the internal combustion oil pan, and the lubricating oil pumped by this oil pump is guided to the crankshaft side. The main oil passage (2) extends toward the camshaft side after the main oil passage (2) is supplied to the camshaft side. Branch out and set up
A four-stroke internal combustion engine characterized in that a part of the lubricating oil flowing through the main oil passage is supplied to the crankshaft through the auxiliary oil passage.