JP2722231B2 - Oil-cooled engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an oil-cooled engine using lubricating oil as a cooling medium.

[Conventional technology]

Engine cooling systems include an air cooling system using traveling wind as a medium, a water cooling system using cooling water as a medium, and an oil cooling system using engine lubricating oil as a medium.

In this oil-cooled engine, a recess is formed near the periphery of the combustion chamber in the cylinder head, and the lubricant generated in the combustion chamber is absorbed by supplying the lubricant in the crankcase to the recess. ing.

[Problems to be solved by the invention]

By the way, in the engine cooling device as described above, since lubricating oil is supplied only to the cylinder head,
The entire engine cannot be uniformly cooled, and the cooling effect of the cylinder head may be impaired.

An object of the present invention is to provide an oil-cooled engine capable of uniformly cooling the entire engine and improving its cooling effect without complicating the structure in view of the above situation.

[Means for solving the problem]

In the oil-cooled engine according to the present invention, a concave portion 18 formed in a portion between the inlet valve 16 and the exhaust valve 17 in the upper portion of the combustion chamber 19 provided in the cylinder head 15, and an inlet valve of the cylinder head 15 It is disposed between the recess 16 and the recess 18, and is open to the camshaft bearings 31, 32, and communicates with the recess 18 through the injection port 30,
A lubricating oil supply passage 27 having a base end opened to the outside of the cylinder head 15; and an exhaust valve 17 side of the cylinder head 15 having one end communicating with the recess 18 and the other end being a cylinder block mounting surface. Lubricating oil discharge passages 25, 26, 28, 35
A plurality of grooves 7,8 surrounding the cylinder liner 6 are formed between the cylinder block 1 and the cylinder liner 6 fitted to the cylinder block 1, and a plurality of lubricating oils O are formed in the plurality of grooves 7,8. A space 11 for cooling the cylinder liner 6 by pumping the oil, and one end is opened at a position connecting to the lubricating oil discharge passages 25, 26, 28, 35 on the cylinder head mounting surface, and the other end is connected to the crankcase. A main gallery 3 having an opening at 37 and a blind plug 4 fitted at an intermediate portion; and an upper communication passage for communicating a portion 3a of the main gallery 3 located above the blind plug 4 with the space 11 5a, a lower communication passage 5b for communicating a portion 3b of the main gallery 3 located below the blind plug 4 with the space 11, and a lubricating oil O stored inside the crankcase 37.
An oil pump 38 for pressure-feeding to an oil cooler 40 via a strainer 39; and a supply pipe from the oil cooler 40 to the outside of the cylinder block 1 and the cylinder head 15 to the base end of the lubricating oil supply passage 27. and c) pumping the lubricating oil O in the crankcase 37 to the oil cooler 40 by the operation of the oil pump 38 and then supplying the oil cooler via the supply pipe c. The lubricating oil O cooled by 40 is fed to the lubricating oil supply passage 27 by pressure, and is branched into two. While being returned to the crankcase 37 via the chain chamber 41, the other is injected into the concave portion 18, and the lubricating oil O cooled around the concave portion 18 is supplied with the lubricating oil discharge passages 25, 26, 28, 35, Above main gallery 3 Min 3a and the upper communication passage
The lubricating oil O, which has been pumped into the cavity 11 via 5a and cooled the cylinder liner 6 in the cavity 11, passes through the lower communication passage 5b and the lower portion 3b of the main gallery 3. It is returned to the inside of the crankcase 37.

[Action]

According to the above configuration, since the lubricating oil O supplied to the concave portion 18 of the cylinder head 15 is further supplied to the space 11 surrounding the entire circumference of the cylinder liner 6 in the cylinder block 1, the cylinder head 15 and the cylinder block 15 1
Can be cooled.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings showing examples.

FIG. 1 conceptually shows an oil-cooled engine according to the present invention. This engine is mounted on a motorcycle, and has a bore 2 in a cylinder block 1 thereof. As shown in FIGS. 3 and 4, the bore 2 has a hole 2a opened on the upper and lower surfaces 1a and 1b of the cylinder block 1.
An annular concave portion 2b formed on the outer periphery of the upper end of the hole 2a.

The cylinder block 1 has a main gallery 3 outside the bore 2. The main gallery 3 opens on the upper and lower surfaces 1a, 1b of the cylinder block 1,
In addition, a blind plug 4 is fitted at the center, and the upper part 3a and the lower part 3b divided into two parts by the blind plug 4 are inserted into the bore 2 via the upper communication passage 5a and the lower communication passage 5b, respectively. Is communicated to.

The upper communication passage 5a and the lower communication passage 5b
Are drilled by a drill or the like from the openings, each of which is inclined toward the opening of the bore 2. The bore 2 and the main gallery 3 are formed simultaneously with the cylinder block 1 by a core or the like when the cylinder block 1 is cast. The inclination angles of the upper communication passage 5a and the lower communication passage 5b are set within 45 ° from the upper surface 1a or the lower surface 1b of the cylinder block 1, respectively.

In this cylinder block 1, as shown in FIG.
A cylinder liner 6 is fitted in the bore 2. As shown in FIG. 4, the cylinder liner 6 has a flange 6a at the upper end.
And an outer peripheral surface of the cylindrical portion 6b.
A plurality of concave grooves 7, 7,... Are formed in 6c. These concave grooves 7, 7 are annular, and are connected to each other by vertical grooves 8, 8 ... formed along the axial direction of the cylinder liner 6. As is clear from the figure, the groove 7 located at the lowermost stage of the cylinder liner 6 is independent of the grooves 7, 7,... A ring 9 is fitted.

The cylinder liner 6 is fitted into the bore 2 of the cylinder block 1 by a cold fit, and the cylindrical portion 6b has a hole.
2a, and the flange 6a is fitted into the recess 2b.

In this state, as shown in FIG. 1, the concave grooves 7, 7 and the vertical grooves 8, 8 of the cylinder liner 6 and the holes 2a of the bores 2 of the cylinder block 1 Vacancies 11 are defined throughout the outer periphery, and the upper connecting passage 5a and the main gallery 3
The above space 11 is formed by the upper part 3a of the cylinder block 1
A connection supply passage 12 is defined to be opened on the upper surface 1a of the main gallery 3, and further a lower communication passage 5b and a lower portion 3b of the main gallery 3 are defined.
This defines a discharge passage 13 that opens the cavity 11 to the lower surface 1b of the cylinder block 1.

A cylinder head 15 is mounted on the upper surface 1a of the cylinder block 1 configured as described above via a gasket 14.

Although not explicitly shown in the drawing, the cylinder head 15 has one camshaft above the central portion, and further has two inred valves 16 and two exhaust valves 17 each operated by the cam of the camshaft. ing.

The cylinder head 15 has a concave portion 18 on the upper surface. The recess 18 is disposed at a position above the combustion chamber 19 between the inlet ports 20, 20 and the exhaust ports 21, 21, and its opening is closed by a lid 22. The cover 22 has a substantially U-shaped cross section, and is fixed to the cylinder head 15 by fastening a bolt 24 to a columnar portion 23 erected in the recess 18.

As shown in FIG. 2, the recess 18 is provided with a pair of communication passages 2.
The stud bolt insertion holes 26, 26 communicate with the stud bolt insertion holes 26, 26 through 5, 25, respectively. One end of each of the communication passages 25, 25 is open at the bottom of both ends of the concave portion 18, and as shown in FIG. 1, the other end is inclined downward outward from the one end. After passing in the vicinity of 17 and around the exhaust ports 21, 21, they are opened to the insertion holes 26, 26.

The cylinder head 15 has a lubricating oil supply passage 27 and a connection discharge passage 28.

The lubricating oil supply passage 27 is configured by burying a pipe 29 in a portion located between the inlet ports 20 and 20 and the concave portion 18 so as to be parallel to a camshaft (not shown). It opens on the side wall of the cylinder head 15 and the other end is closed, and as shown in FIG.
The central part is formed by a plurality of injection ports 30, 30,.
Open inside. The lubricating oil supply passage 27 is also branched from lubricating passages 33 and 34 that open to bearings 31 and 32 of a camshaft (not shown).

As shown in FIG. 1, the connection discharge passage 28 is provided at a position below the exhaust ports 21
It is formed so as to be parallel to 7. This connection exhaust passage 2
8 communicates the stud bolt insertion holes 26, 26 in which the communication passages 25, 25 are open with each other.
An opening is provided at a position corresponding to the opening of the connection supply passage 12 of the cylinder block 1 on the bottom surface of the cylinder head 15 through the opening.

The gasket 14 interposed between the cylinder head 15 and the cylinder block 1 includes a portion corresponding to the cylinder 10 and a portion corresponding to the opening of the connection supply passage 12,
Notches 14a and 14b are formed respectively.

On the other hand, a crankcase 37 is attached to the lower surface 1b of the cylinder block 1 via a gasket 36.

The crankcase 37 has a box shape for storing the lubricating oil O therein, and an opening 37a is formed on an upper surface thereof over a portion corresponding to the opening of the cylinder 10 and the discharge passage 13 of the cylinder block 1.

The crankcase 37 has an oil pump 38 therein. The oil pump 38 has its suction port 38
a is connected to a strainer 39 immersed in the lubricating oil O via a pipe a such as a pipe, and a discharge port 38b thereof is connected to an oil cooler 40 via a pipe b such as a pipe.

The oil cooler 40 is disposed outside the crankcase 37, and has a discharge port 40a connected to the lubricating oil supply passage 27 of the cylinder head 15 via a supply pipe c such as a pipe.

Now, when the engine is started, the oil pump 38 is driven, and the lubricating oil O stored in the crankcase 37 is sucked through the strainer 39.

The lubricating oil O sucked by the oil pump 38 is cooled by the oil cooler 40, and is then sent to the lubricating oil supply passage 27 of the cylinder head 15 via the supply pipe c, and is supplied to the passage 27.
Are sequentially branched. That is, one of the lubrication passages 33, 3
4 to the bearings 31 and 32, and the other
It is jetted and supplied into the recess 18 through 0.

The lubricating oil O supplied to the bearings 31 and 32 leaks therefrom after lubricating with a cam shaft (not shown) and is guided on the upper surface of the cylinder head 15, and
It is returned into the crankcase 37 via the cam chain chamber 41 of the 15 and the cam chain chamber 42 of the cylinder block 1.

On the other hand, the lubricating oil O pumped from the injection ports 30, 30,... Into the concave portion 18 is filled in the concave portion 18 around the combustion chamber 19 in the cylinder head 15, around the inred valves 16, 16, and the exhaust valves 17, 17,. After absorbing the heat of the surroundings and cooling these parts, they are sequentially pressure-fed to the communication passages 25, 25, the stud bolt insertion holes 26, 26, and the connection discharge passage 28. During this time, the lubricating oil O cools around the exhaust ports 21 and 21 in the cylinder head 15.

The lubricating oil O pressure-fed to the connection discharge passage 28
And is fed to the cavity 11 of the cylinder block 1 through the notch 14b of the gasket 14 and the connection supply passage 12.

The lubricating oil O in the cavity 11 is guided to the entire outer periphery of the cylinder 10 along the concave grooves 7, 7,... And the vertical grooves 8, 8,. Cool down.

When the lubricating oil O in the cavity 11 is fed to the lower groove 7 in the cylinder liner 6 by pressure, the lubricating oil O
, Is guided into the cylinder block 1, is further guided downward, and is returned into the crankcase 37.

Thereafter, the above-described operation is repeatedly performed, and the cylinder head 15 and the cylinder block 1 are always cooled during the operation of the engine.

In the above embodiment, grooves 7 and 8 are provided in the cylinder liner 6, and the grooves 1 and 8 are
1, but in the present invention, the cylinder block 1
The space may be defined by providing a groove in the space, or the space may be defined by providing a groove in both.

Further, the groove is constituted by a plurality of annular concave grooves 7, 7 and vertical grooves 8, 8 which connect these concave grooves 7, 7 to each other, but the present invention is not limited to this. Instead, for example, a spiral groove may be used.

〔The invention's effect〕

As described above, according to the oil-cooled engine of the present invention, the lubricating oil O supplied to the recess 18 of the cylinder head 15 is further supplied to the space 11 surrounding the entire circumference of the cylinder liner 6 in the cylinder block 1. Therefore, the cylinder head 15 and the cylinder block 1 can be cooled without complicating the structure, and the entire engine can be uniformly cooled to improve the cooling effect.

In addition, the lubricating oil O supplied to the space 11 is supplied to the lower communication passage 5b and the main gallery 3 provided in the cylinder block 1.
The lubricating oil O can be circulated and used without the need for an external pipe for returning, since the lubricating oil O is returned to the inside of the crankcase 37 via the lower portion 3b of the lubricating oil.

[Brief description of the drawings]

FIG. 1 is a sectional view conceptually showing an oil-cooled engine according to the present invention. FIG. 2 is a top view of a cylinder head portion applied to the oil-cooled engine according to the present invention. Fig. 3 shows a cylinder block portion applied to the oil-cooled engine according to the present invention. Fig. 3 is a top view, and Fig. 4 is an exploded sectional side view. 1 ... Cylinder block, 3 ... Main gallery, 3a
... upper part, 3b ... lower part, 4 ... blind plug, 5a ... upper communication passage, 5b ... lower communication passage, 6 ... cylinder liner, 7, 8 ... concave groove, 11 ... empty Location, 15: Cylinder head, 16: Inlet valve, 17: Exhaust valve, 18: Recess, 19: Combustion chamber, 25: Communication passage, 26 ...
… Stud bolt insertion hole, 27 …… Lubricant supply passage, 28…
… Connection drainage passage, 35 …… Connection drainage passage, 30 …… Injection port, 31,3
2 ... Camshaft bearing, 37 ... Crankcase, 38
…… oil pump, 39 …… strainer, 40 …… oil cooler, 41 …… cam chain chamber, c …… supply line, O ……
Lubricant.

Claims (1)

(57) [Claims] A recess formed in a portion of an upper part of a combustion chamber provided in a cylinder head between an inlet valve and an exhaust valve; an inlet valve of the cylinder head and a recess formed in the cylinder head;
And a lubricating oil supply passage which is open to the camshaft bearings 31 and 32, communicates with the recess 18 through the injection port 30, and has a base end opened to the outside of the cylinder head 15. 27, a lubricating oil discharge passage 25, 26, 28, 35 having one end communicating with the recess 18 and the other end opened to the cylinder block mounting surface on the exhaust valve 17 side of the cylinder head 15; A plurality of grooves 7,8 surrounding the cylinder liner 6 are formed between the block 1 and the cylinder liner 6 fitted to the cylinder block 1, and the lubricating oil O is pumped into the plurality of grooves 7,8. A space 11 for cooling the cylinder liner 6 is provided, and one end is opened at a position where the one end is connected to the lubricating oil discharge passages 25, 26, 28, 35 on the cylinder head mounting surface.
The other end of the main gallery 3 is opened to the crankcase 37, and a blind plug 4 is fitted to an intermediate portion of the main gallery 3. A part 3a of the main gallery 3 located above the blind plug 4 is placed in the space 11. An upper communication passage 5a for communication; a lower communication passage 5b for communicating a portion 3b of the main gallery 3 located below the blind plug 4 with the space 11; lubrication stored in the crankcase 37; An oil pump 38 for pressure-feeding the oil O to an oil cooler 40 via a strainer 39; and a base end of the lubricating oil supply passage 27 passing through the outside of the cylinder block 1 and the cylinder head 15 from the oil cooler 40. And an oil-cooled engine comprising:
After the lubricating oil O in the 37 is pressure-fed to the oil cooler 40, the lubricating oil O cooled by the oil cooler 40 is fed to the lubricating oil supply passage 27 via the supply pipe c to be branched into two. Is supplied to the camshaft bearings 31 and 32, and the lubricating oil O that has lubricated the bearings 31 and 32 is returned to the crankcase 37 via the cam chain chamber 41, while the other is injected into the concave portion 18. The lubricating oil O having cooled the periphery of the recess 18 is supplied to the lubricating oil discharge passages 25, 26, 28, 35, the upper portion 3a of the main gallery 3, and the upper communication passage 5a.
The lubricating oil O, which has cooled the cylinder liner 6 in the cavity 11 via the lower communication passage 5b and the lower portion 3b of the main gallery 3, An oil-cooled engine that is returned to the inside of the crankcase 37.