JPH05141308A - Water jacket structure for internal combustion engine - Google Patents

Abstract

PURPOSE:To improve cooling efficiency by promoting cooling water circulation inside of a bag shape water jacket formed in a cylinder sleeve. CONSTITUTION:A cylinder sleeve 24 is provided with a bag shape water chamber 107 surrounding a cylinder bore, and cooling water is supplied to the inflow side half body HIN from a cylinder head through an opening 1111 of a gasket 111 and an orifice 111, and the cooling water is discharged to the cylinder head from the outflow side half body Hour through an opening 1112 of the gasket 111 and an orifice 1114. Cooling water inflow to the inflow side half body HIN of the water chamber 107 is regulated by means of an orifice 111, and cooling water outflow from the outflow side half body HOUT of the water chamber 107 is also regulated by means of the orifice 1114, and thereby a vortex flow in the arrow A direction is generated in the water chamber 107, so that heat exchange can be promoted between the cooling water and the cylinder sleeve 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a cylinder head with a first water chamber connected to a cooling water supply port and a second water chamber connected to a cooling water discharge port which are separated from each other.
A bag-shaped third water chamber that opens only on the mating surface with the cylinder head is formed inside the cylinder, and the first water chamber and the second water chamber are discharged from the inflow-side half part of the third water chamber. The present invention relates to a water jacket structure of an internal combustion engine, which is in communication with a side half body portion via the mating surfaces.

[0002]

2. Description of the Related Art Conventionally, as a water jacket structure for such an internal combustion engine, one described in JP-A-3-124912 is known.

According to the water jacket structure described above, the cooling water that has flowed into the first water chamber formed in the cylinder head from the cooling water supply port to cool the cylinder head passes through the mating surface between the cylinder head and the cylinder. And flows into the inflow side half of the third water chamber formed in the cylinder, and then into the outflow side half of the third water chamber to cool the cylinder. Then, the cooling water that has cooled the cylinder flows from the third water chamber through the mating surface into the second water chamber formed in the cylinder head, where it cools the cylinder head and is discharged from the cooling water discharge port.

[0004]

By the way, in the above-mentioned conventional water jacket structure, in order to sufficiently enhance the cooling effect of the cylinder, the cooling supplied from the first water chamber on the cylinder head side to the third water chamber on the cylinder side. It is necessary to retain the water inside the third water chamber to sufficiently cool the cylinder, and then discharge the water to the second water chamber on the cylinder head side. However, a part of the cooling water supplied from the first water chamber to the third water chamber does not reach all the inside of the third water chamber and reaches the second water chamber.
There was a problem that the cooling effect of the cylinder was not fully exerted because it was returned to the water chamber.

The present invention has been made in view of the above circumstances, and an object thereof is to sufficiently spread cooling water in a third water chamber formed in a cylinder to improve the cooling effect of the cylinder.

[0006]

To achieve the above object, the present invention provides a first water chamber connected to a cooling water supply port and a second water chamber connected to a cooling water discharge port inside a cylinder head. Are formed separately from each other, and a bag-shaped third water chamber that opens only on the mating surface with the cylinder head is formed inside the cylinder, and the first water chamber and the second water chamber are formed into the third water chamber. In a water jacket structure of an internal combustion engine in which the inflow-side half part and the outflow-side half part of the water chamber communicate with each other through the mating surfaces, at one end of the inflow-side half part of the third water chamber, A throttle means for restricting the inflow of cooling water is provided, and cooling is provided at one end of the outflow side half part of the third water chamber located opposite to one end of the inflow side half part with the center of the cylinder interposed therebetween. The first feature is that throttling means for restricting outflow of water is provided.

In addition to the first feature described above, the present invention also provides
A second feature is that the throttle means is composed of an orifice formed in a gasket that is pressed against the mating surface of the cylinder head and the cylinder.

[0008]

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

1 to 12 show an embodiment of the present invention. FIG. 1 is an overall side view of a motorcycle, FIG. 2 is an overall side view of an internal combustion engine, and FIG. 3 is a line 3-3 of FIG. Cross section map,
4 is an enlarged view of part 4 of FIG. 3, FIG. 5 is an enlarged view of part 5 of FIG. 3, FIG. 6 is an enlarged view of part 6 of FIG. 3, and FIG. 7 is an enlarged view of part 7 of FIG.
FIG. 9 is a view showing a circulation path of cooling water, FIG. 9 is a view taken along line 9-9 of FIG. 4, FIG. 10 is a view taken along line 10-10 of FIG. 4, and FIG. 11 is a perspective view of a cylinder sleeve and a gasket. 12 is a block diagram of the cooling system.

As shown in FIG. 1, a motorcycle V includes a pair of left and right main frames 1, and a front fork 3 is supported by a head pipe 2 connected to the front ends of the main frames 1. The front wheel W is attached to the lower end of the front fork 3.
f is pivotally supported and the steering handle 4
Is provided. Pivot 5 on the rear edge of the mainframe 1
The rear fork 6 is pivotally supported through the shaft so as to be vertically swingable, and the rear wheel Wr is pivotally supported at the rear end of the rear fork 6.

A V-type 4-cylinder 4-cycle internal combustion engine E is suspended and supported below the main frame 1, and the driving force of the internal combustion engine E is transmitted to the rear wheels Wr via a chain 7. An upper radiator 8 and a lower radiator 9 are provided at the front of the internal combustion engine E. Also mainframe 1
A fuel tank 10 is mounted on the upper part of the cross member 1 that connects the rear end of the main frame 1 to the left and right.
1 on the seat frame 12 extending rearward from the seat 1
3 is supported. From the front of the head pipe 2 to the internal combustion engine E
The front cowling 14 covers both sides of the vehicle, and the rear cowling 15 covers the lower portion of the fuel tank 8 to the rear of the seat 11.

As shown in FIG. 2, the internal combustion engine E is provided with an upper case 21 constituting the cylinder block and the upper half of the crankcase, and a lower case 22 constituting the lower half of the crankcase and the mission case. The parts 21 and 22 are joined vertically by a split surface that slopes forward and downward through the axis of the crankshaft 23. Two cylinder sleeves 24 on the front side are fitted to the front part of the upper case 21, two cylinder sleeves 24 on the rear side are fitted to the rear part thereof, and cylinder cylinders 24 are fitted to the upper parts of the cylinder sleeves 24. The head 25 and the head cover 26 are joined. An elliptical piston 27, which will be described later, is slidably engaged with the cylinder sleeve 24, and each piston 2
7 are connected to the crankshaft 23 by two connecting rods 28, respectively.

The cylinder head 25 has an intake port 2
9 and an exhaust port 30 are formed, and an intake port 29 thereof is connected to a throttle body 31 arranged between V banks of the internal combustion engine E. An oil pan 32 and an oil element 3 are provided on the lower surface and the front surface of the lower case 22, respectively.
3, a water pump 34, a rotation speed detector 35 for a speedometer, and a left side surface of the lower case 22 are provided.
A master cylinder 36 of the clutch, which will be described later, is provided. An oil pump (not shown) is provided coaxially with the water pump 34.

[0014] The upper bracket 1 ₁ to the main frame 1, the middle bracket _2, and a lower bracket 1 ₃ are provided, the upper case 21 to the upper bracket 1 ₁
The stay 21 ₁ formed at the center of the
₂ is a stay 22 formed at the rear of the lower case 22.
_1, the bottom bracket 1 ₃ the lower of the lower case 22 are fixed with each bolt 37, 38 and 39, thereby the engine E is supported by suspension on the main frame 1.

Next, the structure of the internal combustion engine E will be described with reference to FIGS.

The crankshaft 23 has its journal supported by five journal metals 41 arranged on the split surfaces of the upper case 21 and the lower case 22, and the four crankpins each have two connecting rods. The big end of 28 is connecting rod metal 4
It is connected via 2. An AC generator 43 is attached to the left end of the crankshaft 23, and the outside of the AC generator 43 is covered with a cover 44.

A main shaft 47 of the mission is supported by a ball bearing 45 provided on the lower case 22 and a ball bearing 46 provided on a partition wall 22 ₂ supported inside the lower case 22, and the lower case 22 is provided behind it.
The counter shaft 50 is supported in parallel by the ball bearing 48 provided on the partition wall 22 and the ball bearing 49 provided on the partition wall 22 ₂ . A wet multi-plate clutch 51 is provided at the right end of the main shaft 47, and the outside thereof is covered with a cover 52. Therefore, by removing the cover 52, the clutch 51, and the partition wall 22 ₂ from the right side surface of the lower case 22, the missions including the main shaft 47 and the counter shaft 50 can be collectively attached and detached from the right side opening portion of the lower case 22. ..

A primary drive gear 53 fixed to the right end of the crankshaft 23 meshes with a primary driven gear 54 rotatably supported by a main shaft 47, and a clutch outer 55 of the clutch 51 has a damper 56 attached to the primary driven gear 54. Connected through. The clutch outer 5 is attached to the main shaft 47.
5 clutch inners 57 so that they are located inside
58 is fixed, and a one-way clutch 59 is attached to one of the clutch inners 58 in order to buffer a shock when the engine brake is operated.

A plurality of drive-side friction plates 60 slidably supported on the clutch outer 56 and a plurality of driven-side friction plates 61 slidably supported on the clutch inners 57 and 58 are axially overlapped with each other, and their outer ends. Pressure plate 62
Is provided. The base end of the pressure plate 62 is connected to a push rod 63 slidably inserted in the main shaft 47 via a ball bearing 64, and a diaphragm spring 65 engages the clutch 51 in the downward direction of FIG. Biased in the direction. Therefore, if the push rod 63 is pressed upward in FIG. 6 by the master cylinder 36 against the urging force of the diaphragm spring 65, the surface pressure of the driving side friction plate 60 and the driven side friction plate 61 by the pressure plate 62 is increased. Disappears and the clutch 51 is disengaged.

Main shaft 47 and counter shaft 5
Gear trains G _{1 to} G ₆ for _{1st to 6th} gears are provided between 0, and a desired gear stage is selectively established by three shift forks 66, 67, 68 driven by a shift drum (not shown). To be done. A drive sprocket 69 around which the chain 7 for driving the rear wheels Wr is wound is provided at the left end of the counter shaft 50, and the rotation speed detector 36 is coaxially connected to the outside thereof.

The piston 27 that slides on the left and right cylinder sleeves 24 _L has an elliptical shape whose major axis extends in the left-right direction, and the top surface of the piston 27 and the cylinder head 25.
The combustion chamber 70 defined by
The four intake valves 72 and the four exhaust valves 73 face each other. The intake valve 72 and the exhaust valve 73 are provided with a valve spring 74 and a valve lifter 75, and an intake cam 77 and an exhaust camshaft 7 provided on the intake camshaft 76 are provided.
The exhaust-side cams 79 provided on the contact surfaces 8 come into contact with the corresponding valve lifters 75.

The intake-side cam gear 80 and the exhaust-side cam gear 81 provided at the right ends of the intake-side camshaft 76 and the exhaust-side camshaft 78 respectively correspond to idle gears 82 and 8 respectively.
3 and a cam drive gear 85 provided on the crankshaft 23 via a common idle gear 84.
It rotates at a speed one-half the speed.

Next, the internal combustion engine E will be described with reference to FIGS.
The cooling system will be described in detail.

As shown in FIG. 8, the water pipe 101 extending from the water pump 34 mounted on the left side surface of the lower case 22 of the internal combustion engine E is bifurcated into a forked water supply port 25 _{1 of the} front and rear cylinder heads 25. And the cooling water discharge ports 25 of both cylinder heads 25.
₂ is the thermo case 10 through the water pipe 102
3 is connected. The cooling water is the thermo case 103.
Is supplied to the radiators 8 and 9 through a water pipe (not shown), and is then returned to the water pump 34 through the water pipe 104.

FIG. 9 shows a state in which the cylinder head 25 of the front bank of the internal combustion engine E is viewed from the mating surface side with the cylinder sleeve 24. The right half of the drawing is the exhaust side and the left half is the intake side. Becomes In the cylinder head 25, a first water chamber 105 communicating with the cooling water supply port 25 ₁ and a second water chamber 106 communicating with the cooling water discharge port 25 ₂ are formed. 25 ₃ prevent mutual communication. The first water chamber 105 includes six elliptical communication holes 1 so as to surround the exhaust-side half circumference of each combustion chamber 70.
05 _{1-105 6} are formed, their six communication holes 10
5 ₁ to 10 5 ₆ open on the mating surface with the cylinder sleeve 24. Further, in the second water chamber 106, six elliptical communication holes 106 are provided so as to surround the intake side half circumference of each combustion chamber 70.
_{1-106 6} are formed, their six communication holes 106 ₁
- 106 ₆ also opens the mating surface of the cylinder sleeve 24.

10 and 11 show a cylinder sleeve 24 to which the cylinder head 25 is joined via a gasket 111. Cylinder sleeve 24
2 are provided corresponding to each of the cylinder heads 25, a flange portion 24 ₁ sandwiched between the cylinder head 25 and the upper case 21, and a cylinder portion 24 ₂ into which the piston 27 is slidably fitted. Equipped with. The cylinder head 25, the gasket 111, and the cylinder sleeve 24 are fastened together with the upper case 21 by a plurality of bolts 112.

Cylinder portion 24 of cylinder sleeve 24₂
Has a bag-shaped third water chamber 107 whose upper part is open.
It is formed so as to surround the outer circumference of the cylinder bore. sand
That is, twelve elliptical communication is made on the upper part of the third water chamber 107.
Hole 107₁~ 107₁₂Are formed, and six of them are formed.
Through hole 107₁~ 107₆Is the inflow half of the third water chamber 107
Part H_INAnd the first of the cylinder head 25
The six communication holes 105 connected to the water chamber 105₁~ 105
₆And the remaining six communication holes 107 facing each other.₇~ 107
₁₂Is the outflow-side half H of the third water chamber 107_OUTTo communicate with
Both are connected to the second water chamber 106 of the cylinder head 25.
The six communication holes 106₁~ 106₆To face. gas
The inflow-side half H of the third water chamber 107_IN
Corresponding to 8 circular openings 111 each₁And that
From opening 111₁Smaller than two orifices 111₃
And the outflow-side half of the third water chamber 107
H _OUTCorresponding to 8 circular openings 111 each₂
And those openings 111₂Smaller than two orifices 1
11_FourIs formed. As is clear from FIG.
Liffith 111₃Is the cooling water supply port 25 of the first water chamber 105.
₁Is located at the position closest to the
1_FourIs the cooling water discharge port 25 of the second water chamber 106.₂Farthest from
It is installed at a certain position.

The cooling water supplied from the cooling water supply port 25 ₁ to the first water chamber 105 is the same as that of the cylinder head 25.
Number of communication holes 105 _{1-105 6,} 8 of the gasket 111
Openings 111 ₁ and 2 orifices 111 ₃ , and 6 communication holes 107 _{1 to} 107 of the cylinder sleeve 24.
_It flows into the inflow side half body H _IN of the third water chamber 107 via ₆ . Further, the cooling water in the outflow-side half body H _OUT of the third water chamber 107 is supplied to the six communication holes 107 ₇ to _{7 7} of the cylinder sleeve 24.
107 ₁₂ , eight openings 111 ₂ and 2 of the gasket 111
The second water chamber 10 through the _six orifices 111 ₄ and the six communication holes 106 _{1 to} 106 6 of the cylinder head 25.
Inflow to 6.

Next, the operation of the embodiment of the present invention having the above-mentioned structure will be described with reference to the block diagram of FIG.

The cooling water discharged from the water pump 34 is supplied to the cooling water supply port 25 provided on the exhaust side of the cylinder head 25 before and after the internal combustion engine E via the water pipe 101.
₁ is supplied to the inside of the first water chamber 105 shown in FIG. The cooling water flowing into the first water chamber 105 cools the exhaust side of the cylinder head 25, and then the eight communication holes 105 _{1 to} 105 ₆ formed in the cylinder head 25 form the eight openings 111 formed in the gasket 111. Pass through ₁ and 2 orifices 111 ₃ and then cylinder sleeve 2
It flows into the inflow side half part H _IN of the third water chamber 107 formed in the cylinder sleeve 24 through the _six communication holes 107 _{1 to} 1076 formed in 4 (see FIGS. 10 and 11). The cooling water that has flowed into the inflow side half body H _IN of the third water chamber 107 is discharged from the outflow side half body H _{OUT of} the third water chamber 107.
It flows into the further from there the cylinder sleeve 24 six communication holes 107 _{7-107 12} formed in the gasket 111
Eight opening formed in 111 ₂ and two orifices 11
1 _4, and flows into the second water chamber 106 of the cylinder head 25 through the six communication holes 106 _{1-106 6} formed in the cylinder head 25. While the cooling water cools the cylinder sleeve 24 while flowing through the third water chamber 107 of the cylinder sleeve 24,
While flowing through the water chamber 106, the intake side of the cylinder head 25 is cooled. Then, the cooling water discharge port 2 of the second water chamber 106
5 ₂ cooling water discharged from the flows in the thermo-case 103 through the water pipe 102, flows back to the water pump 34 from there through the upper radiator 8 and the lower radiator 9.

As is clear from FIGS. 10 and 11, most of the cooling water flowing into the inflow-side half body H _IN of the third water chamber 107 of the cylinder sleeve 24 is mostly the gasket 1.
Corresponding to the opening 111 ₁ of 11 four communication holes 107 ₃ -
Inflow from 107 ₆ and the orifice 1 of the gasket 111
The amount of inflow from the _two communication holes 107 ₁ and 107 ₂ corresponding to 11 ₃ is extremely small. On the other hand, most of the cooling water that flows out from the outflow side half portion H _OUT of the third water chamber 107 of the cylinder sleeve 24 is in the opening 11 of the gasket 111.
1 ₂ flows out from the four communication holes 107 _{8-107 12} corresponding amount flowing out from the communicating hole 107 _7, 107 ₈ two corresponding to orifice 111 ₄ of the gasket 111 becomes negligible.

Therefore, when the cooling water flows from the first water chamber 105 to the inflow side half portion H _IN of the third water chamber 107, most of the cooling water passes through the upper part of the orifice 111 ₃ and the above-mentioned 4 to flowing from pieces of communication holes 107 _{3-107 6} to the inlet side half portion H _iN of the third water chamber 107, the cooling water in the inflow-side halves H _iN will flow in the arrow a direction. Further, when the cooling water flows out from the outflow side half portion H _{OUT of} the third water chamber 107 to the second water chamber 106, most of the cooling water passes through the lower part of the orifice 111 ₄ and the above-mentioned 4
From the individual communication holes 107 _{9 to} 107 ₁₂ to the second water chamber 106.
In this case, the cooling water flowing through the outflow-side half body H _OUT is directed in the direction of arrow A as described above. Thus, the cooling water supplied to the inflow side half body H _IN of the third water chamber 107 becomes a vortex in the direction indicated by the arrow A in FIGS. 10 and 11, and is directed toward the outflow side half body H _OUT . The cooling water can reach every corner of the third water chamber 107. Thereby, the heat exchange between the cooling water and the cylinder sleeve 24 is sufficiently performed, and the cooling effect of the cylinder sleeve 24 is enhanced.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various small design changes can be made.

For example, instead of forming the throttle means on the gasket, the throttle means may be formed directly on the cylinder sleeve. Further, in the embodiment, the internal combustion engine having the elliptical piston is illustrated, but the present invention can be applied to an internal combustion engine having a normal circular piston.

[0035]

As described above, according to the first feature of the present invention, the inflow of cooling water enters one end of the inflow side half of the third water chamber and one end of the outflow side half opposite to the third water chamber. And the throttle means for restricting the outflow are respectively provided, so that the swirling flow of the cooling water surrounding the outer periphery of the cylinder bore is generated inside the third water chamber and the cooling water is spread to every corner inside the third water chamber. be able to. Accordingly, the time during which the cooling water stays inside the third water chamber can be extended and the cooling effect of the cylinder can be improved.

Further, according to the second feature of the present invention, since the throttle means is constituted by the orifice formed in the gasket which is sandwiched between the mating surfaces of the cylinder head and the cylinder, it is special to the conventional cylinder head and cylinder. The squeezing means can be added by simply replacing the gasket without processing.

[Brief description of drawings]

[Figure 1] Overall side view of a motorcycle

FIG. 2 is an overall side view of an internal combustion engine

FIG. 3 is a map of a sectional view taken along line 3-3 of FIG.

4 is an enlarged view of part 4 of FIG.

5 is an enlarged view of part 5 of FIG.

6 is an enlarged view of part 6 in FIG.

7 is an enlarged view of part 7 in FIG.

FIG. 8 is a diagram showing a circulation path of cooling water.

9 is a sectional view taken along line 9-9 of FIG.

10 is a sectional view taken along line 10-10 of FIG.

FIG. 11 is a perspective view of a cylinder sleeve and a gasket.

FIG. 12 is a block diagram of a cooling system.

[Explanation of symbols]

24 ... Cylinder sleeve (cylinder) 25 ... Cylinder head 25 ₁ ... Cooling water supply port 25 ₂ ... Cooling water discharge port 105 ... First water chamber 106 ... Second water Chamber 107 ... Third water chamber 111 ... Gasket 111 ₃ ... Orifice (throttle means) 111 ₄ ... Orifice (throttle means) H _IN ... Inflow side half H _OUT ... Outflow side Half body

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location F16J 15/08 F 7233-3J

Claims (2)

[Claims] 1. A first water chamber (105) connected to a cooling water supply port (25 ₁ ) and a second water chamber (106) connected to a cooling water discharge port (25 ₂ ) inside a cylinder head (25). Are formed so as to be separated from each other, and a bag-shaped third water chamber (107) is formed inside the cylinder (24), the bag-shaped third water chamber (107) opening only on the mating surface with the cylinder head (25).
The water chamber (105) and the second water chamber (106) are connected to the inflow side half body (H _IN ) and the outflow side half body (H _OUT ) of the third water chamber (107) via the mating surface. In a water jacket structure of an internal combustion engine that communicates with each other, a throttle means (111 ₃ ) for restricting the inflow of cooling water is provided at one end of an inflow side half body (H _IN ) of the third water chamber (107). Along with the center of the cylinder (24), one end of the outflow half body (H _OUT ) of the third water chamber (107) located opposite to one end of the inflow half body (H _IN ). A water jacket structure for an internal combustion engine, characterized in that a throttle means (111 ₄ ) for restricting the outflow of cooling water is provided in the. 2. An orifice (11) formed by the throttle means in a gasket (111) that is pressed against the mating surface of the cylinder head (25) and the cylinder (24).
1 _3, 111 _4), characterized in that is constituted by, the water jacket structure for an internal combustion engine according to claim 1.