JP3057420B2 - Siamese cylinder cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling apparatus for a siamese cylinder of a multi-cylinder engine, which increases the strength of a continuous wall of the cylinder, cools the head-side portion strongly, and reduces the relative size of the multi-cylinder engine. Provide something that can reduce weight and increase output.

[0002]

2. Description of the Related Art In recent years, the interval between cylinder bores has to be narrowed to reduce the size and weight of a multi-cylinder engine, or the cylinder bore has to be increased by increasing the cylinder bore to increase the engine output by increasing the displacement. Siamese cylinders with as thin a wall as possible have come to be used. Examples of this type of prior art include, for example,
The one disclosed in -68155 is known.

FIG. 9 shows the above conventional example, FIG. 9 (A) is a longitudinal sectional view of a main part of a siamese cylinder, and FIG. 9 (B) is a plan view taken along line BB in FIG. 9 (A). FIG. 9C shows a head-side portion 4a of the continuous wall portion 4 of the siamese cylinder.
FIG. 4 is a perspective view of a water channel forming member cast into the tub. In this conventional example, a plurality of cylinders 3 are arranged side by side in a cylinder block 1 and adjacent cylinders 3 are connected by a continuous wall portion 4 to form a siamese cylinder 2. The siamese cylinder 2 is surrounded. A water jacket forming member 10 is cast in the continuous wall portion 4.

The water channel forming member 10 is shown in FIGS. 9A and 9B.
As shown in (C), a cooling water passage 15 communicating the left and right cylinder jackets 8 of the continuous wall portion 4 and a pair of right and left cooling water passages 15 located at both left and right ends of the cooling water passage 15 and communicating with the cooling water passage 15. , And a pair of left and right cooling water introduction portions 13, 13 located below the jacket communication passages 12, 12 and open toward the respective cylinder jackets 8.8, The cooling water flowing from the cooling water introduction portions 13 flows through the cooling water passage 15 and passes through the jacket communication passages 12 to a head jacket (not shown) located above the head leaning portion 4a. Spilled, meanwhile the head portion 4 of the continuous wall portion 4
a is cooled. The cooling water passage 15 is integrally formed by caulking two metal molded plates at a caulking portion 18.

[0005]

In the above prior art, since the cooling water passage 15 is flat, when machining the cylinder bore 3a, insufficient strength occurs at a portion corresponding to the cooling water passage 15, and consequently, the locality of the cylinder bore 3a is reduced. There is a risk of distortion. In order to avoid this, it is necessary to increase the thickness of the continuous wall portion 4 to some extent. In other words, in this conventional example, the thickness of the continuous wall portion 4 cannot be sufficiently reduced, so that the interval between the cylinder bores 3a is reduced.
Alternatively, there is a difficulty in increasing the engine output by increasing the displacement.

The cooling water introduction part 13 is formed by cutting out the lower part of the cylindrical body constituting each jacket communication passage 12. However, since the cooling water introduction part 13 has a small opening, a large amount of cooling water is provided. Cannot be smoothly introduced into the cooling water passage 15. Moreover, the flow velocity in the cooling water passage 15 cannot be increased, and there is a disadvantage that the head-side portion 4a of the continuous wall portion 4 cannot be cooled powerfully. As described above, if the head-side portion 4a of the continuous wall portion 4 cannot be cooled strongly and the heat radiation capability is low, the output of the engine cannot be increased.

That is, the piston ring is cooled via the cylinder wall. However, if the heat radiation ability of the head-side portion 4a is low, the top ring is particularly fixed from the top of the piston from the viewpoint of preventing seizure of the piston ring. I have to wear it at a distance. This means that a ring-shaped dead space which does not contribute to combustion occurs on the outer periphery of the piston top. For this reason, it is not possible to improve the air utilization rate, and as a result, it is not possible to increase the output of the engine.

In particular, in recent years, it has been required to further reduce the size and weight of the engine and to increase the output of the engine. However, since the conventional example has the above-mentioned disadvantages, it is not possible to sufficiently meet these requirements. Moreover, since the water channel forming member 10 is integrally formed as shown in FIG. 9 (C), the cooling water channel 15 is welded to the jacket communication channel 12 or is molded to form the same. However, in any case, it takes time and effort to manufacture, and the cost is high.

The present invention has been made in view of such circumstances, and aims to increase the strength of a continuous wall portion into which a channel forming member is cast, and to reduce the thickness of the continuous wall portion to the minimum. To further reduce the size and weight of multi-cylinder engines and improve the output of the engine, and to further enhance the air utilization rate by cooling the head-side portion of the continuous wall and positioning the top ring higher. It is a technical task to improve the output of the engine, to simplify the production of the waterway forming member, and to reduce the cost of the member.

[0010]

In order to solve the above-mentioned problems, the present invention is configured as follows. That is, the basic configuration of the siamese cylinder cooling device according to the present invention is based on the head-side portion 4 of the continuous wall portion 4 of the siamese cylinder 2.
a, the channel forming member 10 is cast into the cylinder jacket 8.
The cooling water in 8 is configured to flow out to the head jacket 22 located above the continuous wall portion 4 via the water channel forming member 10.

According to the first aspect of the present invention, in the cooling apparatus for a siamese cylinder having the above-described basic configuration, the water passage forming member 10 includes a pair of left and right jacket communication passages 12 located in an upper half portion, Communication passage 1
Located on the lower side of 2.12, each cylinder jacket 8.8
Left and right pair of cooling water introduction parts 13
And between the left and right jacket communication passages 12 and 12 and between the left and right cooling water introduction portions 13 and 13, each of which includes a non-hollow portion 11 and a cooling water passage 15 alternately formed in upper and lower stages. Each cooling water passage 15 is characterized in that it is configured symmetrically so that the tip formed in a wedge shape in a plan view faces the center, and the wedge-shaped tips communicate with each other through a minute gap S. .

According to a second aspect of the present invention, in the cooling device for a siamese cylinder having the above-described basic configuration, the water passage forming member 10 includes a pair of left and right jacket communication passages 12 and 12 located in an upper half portion, Communication passage 1
Located on the lower side of 2.12, each cylinder jacket 8.8
Left and right pair of cooling water introduction parts 13
And between the left and right jacket communication passages 12 and 12 and between the left and right cooling water introduction portions 13 and 13, each having a non-hollow portion 11 and a cooling water passage 15 alternately formed in upper and lower stages. Each cooling water passage 15 is characterized in that it is configured symmetrically so that the front end formed in a wedge shape in a plan view faces the center, and the wedge-shaped front end is closed as a non-hollow portion 11b.

According to a third aspect of the present invention, in the cooling device for a siamese cylinder according to the first or second aspect, at least the upper edge (15b) of each cooling water passage (15) is inclined upward and outward in the left-right direction. It is formed. Here, “at least” means that the upper edge 15b of the pair of left and right cooling water passages 15 is formed so as to have an upward slope outward in the left-right direction, and the lower edge 15c of each cooling water passage 15 is outwardly directed in the left-right direction. It means that it does not matter whether it is formed on an upward slope.

According to a fourth aspect of the present invention, in the cooling device for a siamese cylinder according to any one of the first to third aspects, the water passage forming member 10 is provided in each of the non-hollow portions 11 formed in a vertically multi-stage manner. The front and rear wall connecting holes 16 for connecting the front and rear wall of the continuous wall 4 are formed.

According to a fifth aspect of the present invention, in the cooling apparatus for a siamese cylinder according to any one of the first to fourth aspects, the water channel forming member 10 is formed of two metal plate-like members 10a. Are formed symmetrically by molding, and outer edge joints 17 are formed so as to protrude from the outer edges of the left and right jacket communication passages 12 vertically, and at least the outer edge joints 17 are fixed to each other. It is configured integrally.

According to a sixth aspect of the present invention, in the cooling apparatus for a siamese cylinder according to the fifth aspect, a pair of left and right cylinder head fastening bosses is provided on both left and right sides of the head-side portion 4a of the continuous wall portion 4. 5, one outer edge joint 17 is provided between one cylinder 3 and the cylinder head fastening boss 5, and the other outer edge joint 17 is provided between the other cylinder 3 and the cylinder head. It is configured such that one and the other are deflected toward the cylinder 3 between the fastening boss portions 5 and cast.

[0017]

According to the first aspect of the present invention, since the non-hollow portions 11 and the cooling water passages 15 are alternately formed in upper and lower tiers, the non-hollow portions 11 are connected to the continuous wall portions 4. Function as a rib for mechanically reinforcing the. That is, the cooling water passages 15 formed alternately and vertically in multiple stages with the non-hollow portions 11 have significantly higher mechanical strength than the flat and vertically long cooling water passages 15 of the conventional example. As a result, there is no possibility that partial distortion will occur in the drilling of the cylinder bore 3a.

The thickness of the continuous wall portion 4 is the thinnest at the center portion and the thickest at both right and left ends. In the invention according to claim 1, the thickness of the continuous wall portion 4 corresponds to the thickness. Thus, the cooling water passage 15 is formed in a wedge shape in plan view, and the cooling water passage 15 is formed symmetrically so that the tip thereof is directed to the center. Therefore, the water passage forming member 10 can be made thinner, and the continuous wall portion 4 can be made thinner. Thereby, the thickness of the continuous wall portion 4 can be made thinner than the conventional example, and the pitch between the cylinder bores can be reduced. Alternatively, the displacement can be increased and the output can be increased by increasing the diameter of the cylinder bore.

According to the first aspect of the present invention, since each of the cooling water passages 15 has a wedge-shaped leading end communicating with each other through the minute gap S, the cooling water flowing through the minute gap S is formed. The flow rate of water is increased, and the cooling efficiency is further increased. That is, the cooling water in the cylinder jackets 8.8 flows in from the cooling water introduction portions 13 and flows into the wedge-shaped cooling water passage 15 and the jacket communication passage 12 in large amounts.
The continuous wall portion 4 passes through the jacket communication passages 12.
Of the cooling water flowing through the small gap S, the cooling water flowing through the minute gap S becomes faster, and the head-side portion 4a is cooled strongly. Then, the piston ring is cooled strongly through the cylinder wall. As a result, the top ring can be brought as close as possible to the top surface of the piston, and a ring-shaped dead space that does not contribute to combustion on the outer periphery of the top portion of the piston can be minimized, thereby improving the air utilization rate. Accordingly, it is possible to eliminate the sticking of the top ring due to the carbonization of the unburned portion of the fuel and the lubricating oil.

With the top ring as close as possible to the piston top surface, the position of the piston pin is made as close as possible to the piston top surface, and the swinging dimension of the crankshaft can be lengthened accordingly. , Without changing the physique (height) of the connecting rod or engine, piston stroke,
As a result, the displacement can be increased. That is, it is possible to reduce the size of the multi-cylinder engine and increase the output of the engine. Conversely, when the piston stroke is not changed, the connecting rod can be set longer by an amount corresponding to the position of the piston pin closer to the piston top surface, so that the pressure on the piston side can be reduced, and as a result, the friction loss can be reduced.

According to the second aspect of the present invention, since each of the cooling water passages 15 has a wedge-shaped front end closed as a non-hollow portion 11b in a plan view, the continuous wall portion 4 has the smallest thickness. The channel forming member 10 can be made thinner at the center, and the continuous wall portion 4 can be made as thin as possible.
Thereby, the thickness of the continuous wall portion 4 can be made thinner, and the pitch between the cylinder bores can be reduced.

According to the third aspect of the present invention, since at least the upper edge 15b of each of the pair of left and right cooling water passages 15 formed in the water passage forming member 10 is formed so as to be inclined upward and outward in the left-right direction, each cooling water passage should be used. Even when the cooling water boils within the cooling water 15 and water vapor is generated, the water vapor moves upward along the upper edge 15b of each cooling water passage 15 formed uphill, and passes through the jacket communication passage 12 to the head jacket 22. escape. This keeps the cooling performance high.

In the invention described in claim 4, the front and rear wall walls of the continuous wall section 4 are connected by forming the front and rear wall connection holes 16 in the non-hollow portions 11 formed in the upper and lower stages of the waterway forming member 10. Therefore, the pressing force acting on the continuous wall portion 4 at the time of drilling the bore of the cylinder bore 3a or operating the engine can be more strongly countered, so that the mechanical strength is also remarkably increased in this respect, and the bore of the cylinder bore 3a is increased. In processing, there is no possibility that partial distortion occurs.

According to the fifth aspect of the invention, the water channel forming member 10 is formed by symmetrically forming the two metal plate-like members 10a, 10a, and forming the left and right jacket communication passages 12.1.
2 are formed so as to protrude outwardly at the outer edge of the outer plate 2 and at least the outer edge joints 17 are fixed to each other so as to be integrally formed.
The waterway forming member 10 can be easily manufactured simply by fixing the members 0a to each other, and the cost of the member can be reduced.

In the invention described in claim 6, both left and right sides of the head-side portion 4a of the continuous wall portion 4 are formed to be continuous with a pair of left and right cylinder head fastening bosses 5, 5 and one outer edge is joined. The portion 17 is provided between one cylinder 3 and the boss portion 5 for fastening the cylinder head, and the other outer edge joint portion 17 is provided.
Is a boss 5 for fastening the other cylinder 3 to the cylinder head.
Between the cylinder and the other cylinder 3, respectively, so that compared to the conventional example in which the joining portion is simply overlapped outside the left and right jacket communication paths, Twelve substantial passage cross-sections can be increased.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a channel forming member according to a first embodiment of the present invention, FIG. 1 (A) is a perspective view of the channel forming member, FIG. 1 (B) is a plan view of a right half of the channel forming member cut away, 1C is a vertical cross-sectional view taken along line CC in FIGS. 1A and 2B, and FIG. 2 is a front view of the water channel forming member. 7 shows a main part of a vertical multi-cylinder engine equipped with a siamese cylinder cooling device according to the present invention. FIG. 7 (A) is a partial vertical sectional view, and FIG. 7 (B) is a part of the cylinder block. It is a top view. FIG. 8 is a longitudinal sectional view of a main part of a vertical multi-cylinder engine equipped with a siamese cylinder cooling device according to the present invention.

As shown in FIG. 8, the vertical multi-cylinder engine E has a cylinder head 20 fixed on a cylinder block 1 integrally formed with a crankcase with a head bolt 6, and a cylinder formed on the cylinder block 1. The jacket 8 and the head jacket 22 formed on the cylinder head 20 are communicated with each other through a large number of jacket communication holes 24 formed on portions other than the continuous wall portion 4, and the cylinder head 20 is cooled with cooling water that has cooled the cylinder block 1. It is configured to be.

The siamese cylinder cooling device according to the present invention has the same basic configuration as that of the conventional example. That is,
As shown in FIGS. 7 and 8, a plurality of cylinders 3 are juxtaposed in front and rear on a cylinder block 1, and adjacent cylinders 3.
Are continued by the continuous wall portion 4 to form the siamese cylinder 2, and a cylinder jacket 8 is formed so as to surround the siamese cylinder 2. A water channel forming member 10 described below is cast into the continuous wall portion 4.

Hereinafter, the characteristic structure of the present cooling device will be described. As shown in FIGS. 1 and 2, the water channel forming member 10 includes two metal plate-like members 10a, 10a formed symmetrically by press molding, facing each other and overlapping each other. Outer edge joints 17, which are formed by projecting outward from the outer edge of the outer edge 12, are integrally formed by seam welding. Thereby, the outer edge joining portion 1 of the two metal plate-like bodies 10a, 10a molded into the same shape is formed.
Simple and inexpensive manufacture can be achieved simply by adhering 7.17 to each other. The arc spot welding according to the third and fourth embodiments described later may be replaced with the seam welding.

The water channel forming member 10 is provided with a pair of left and right jacket communication passages 12 and 12 located in the upper half portion, and is positioned below the jacket communication passages 12 and 12 toward each cylinder jacket 8.8. A pair of left and right cooling water introduction portions 13, 13, and non-hollow portions 11 a formed alternately between the left and right jacket communication passages 12, 12 and between the left and right cooling water introduction portions 13, respectively. The cooling water in the cylinder jacket 8.8 is supplied to a pair of left and right cooling water introduction portions 13 and 13 and the cooling water passages 15.
And the jacket communication passages 12, 12, in order, to flow out to the head jacket 22 located above the continuous wall portion 4.

Note that reference numeral 16 in FIGS. 1A and 2
Are front and rear wall connecting holes for connecting the front and rear wall of the continuous wall 4. Since the non-hollow portion 11a of the present invention has the front and rear wall connecting holes 16 formed in a long hole, the continuous wall is not affected by the pressing force acting on the continuous wall 4 at the time of machining the cylinder bore or operating the engine. There is an advantage that the wall 4 can be more strongly opposed. The non-hollow portion 11a formed in the upper and lower tiers functions as a rib for mechanically reinforcing the continuous wall portion 4, and the cooling water passage 15 formed in the upper and lower tiers alternately with the non-hollow portion 11a Compared to the flat, vertically long cooling water channel 15, the mechanical strength is significantly increased. As a result, there is no possibility that partial distortion will occur in the drilling of the cylinder bore 3a.

As shown in FIGS. 1A and 1B and FIG. 2, each of the cooling water passages 15 is formed in a wedge shape in plan view, and is configured symmetrically so that its tip is directed to the center. That is,
The thickness of the continuous wall portion 4 is the thinnest at the center portion and the thickest at both right and left ends. The cooling water passage 15 is formed in a wedge shape in plan view corresponding to the thickness of the continuous wall portion 4. By symmetrically configuring the front end to the center, the water channel forming member 10 can be made thinner than the conventional example, and the continuous wall portion 4 can be made thinner. Thereby, the pitch between the cylinder bores can be reduced. Alternatively, the displacement can be increased and the output can be increased by increasing the diameter of the cylinder bore.

The pair of left and right cooling water passages 15 is shown in FIG.
(B) As shown in (C), the central portion (wedge-shaped tip portion) is formed so as to communicate with each other via the minute gap S, so that, for example, a wedge-shaped cooling water channel is formed by a manual molding machine. When the casting sand is packed in the inside 15, it is convenient because the sand can be compacted from one side in the left-right direction. Also,
The flow rate of the cooling water flowing through the minute gap S increases, and the cooling efficiency further increases. Moreover, each wedge-shaped cooling water channel 1
The upper edge 15b of the fifth member 5 is formed so as to rise outward in the left-right direction. That is, even when the cooling water boils in each of the wedge-shaped cooling water passages 15 to generate steam, the steam moves upward along the upper edge 15b of each cooling water passage 15 formed on the upward slope, and the jacket communication passage is formed. 12 through the head jacket 2
Escape to 2. This keeps the cooling performance high.

Further, a pair of left and right cooling water introduction portions 13 is provided.
Is a pair of front and rear cooling water guide plates 14.
4 is expanded along each outer peripheral surface 3b of the adjacent cylinder 3.3. Thereby, the frontage of the cooling water introduction portions 13 is formed large. Therefore, much of the cooling water is
A large amount of water flows into the cooling water passage 15 and the jacket communication passage 12 from the cooling water introduction portions 13 and 13 expanded toward 8, and is located above the continuous wall portion 4 through the jacket communication passages 12 and 12. Exit to the head jacket 22. Also,
The flow rate of the cooling water flowing through the minute gaps S is increased, and the cooling efficiency is further increased, so that a large amount of the cooling water strongly cools the head-side portion 4a.

That is, since the piston ring can be strongly cooled through the cylinder wall by strongly cooling the head-side portion 4a, the top ring is brought as close as possible to the top surface of the piston, and combustion of the outer periphery of the top portion of the piston is prevented. The ring-shaped dead space that does not contribute can be reduced as much as possible to improve the air utilization rate. In addition, the sticking of the top ring due to the carbonization of the unburned portion of the fuel can be eliminated.

In addition, as the top ring is brought as close as possible to the piston top surface, the position of the piston pin is brought as close as possible to the piston top surface, and the swinging dimension of the crankshaft is lengthened accordingly. It is possible to reduce the size of the connecting rod engine without changing its height, increase the piston stroke, and increase the displacement. Further, since the head-side portion 4a can be cooled strongly, the displacement can be increased by increasing the diameter of the cylinder bore. Furthermore, by applying the present invention to a multi-cylinder engine or the like equipped with a turbocharger, it is possible to achieve a relative reduction in size and an increase in engine output. Conversely, when the piston stroke is not changed, the connecting rod can be set longer by an amount corresponding to the position of the piston pin closer to the piston top surface, so that the pressure on the piston side can be reduced, and as a result, the friction loss can be reduced.

As shown in FIG. 1B, the left and right sides of the head-side portion 4a of the continuous wall portion 4 and the pair of left and right cylinder head fastening bosses 5, 5 are formed continuously. The distance between the head bolts 6 is reduced, and the cylinder 3 is fastened uniformly and strongly along the circumferential direction by the reduced amount. The present invention is not limited to this, but by connecting the cylinder head fastening bosses 5 and the left and right sides of the head shift portion 4a with each other, the jacket communication hole 23 formed in the upper end wall of the cylinder block 1 is formed. There is an advantage that a large amount of cooling water can be circulated by increasing the hole diameter of the pair of jacket communication paths 12.

As shown in FIGS. 1 (B) and 7 (B), one outer edge joint 17 of the outer edges of the jacket communication passages 12 is connected to one cylinder 3 and the cylinder head fastening boss 5. Between the other cylinder 3 and the boss 5 for fastening the cylinder head.
Each of the cylinders is cast so as to be deviated toward one of the cylinders 3 and the other. That is, since the interval between the left and right cylinder head fastening bolts 6 is constant, if the joining portion 17 is simply overlapped on the outside of the left and right jacket communication passages 12, the substantial passage cross section of the jacket communication passage 12 will be changed. Narrows. Therefore, as described above, the outer edge joints 17.
By displacing 7 toward one and the other cylinder 3, it is possible to increase the substantial passage cross section of the jacket communication passage 12.

As shown in FIGS. 1B, 7A, and 7B, the pair of jacket communication passages 12, 12 are located inside the bosses 5, 5, and the upper end wall of the cylinder block 1 and It communicates with the jacket communication holes 23 formed in the lower end wall of the cylinder head 20. Further, as shown in FIG. 1A, the upper end of the jacket communication passage 12 is slightly higher in height than the non-hollow portion 11 at the upper end. This corresponds to the jacket communication hole 2 in the upper end wall of the cylinder block 1.
By setting the length 3 relatively short, the sand core 12b for forming the jacket communication hole 23 is intended to be hardly broken.

FIG. 3 is a front view of a water channel forming member according to a second embodiment of the present invention. In this embodiment, as shown in FIG. 3, outer edge joints 17, 17 formed by projecting outward at the outer edges of the left and right jacket communication passages 12, 12 and the non-hollow portions 11 at the lower end, respectively. Are fixed together by seam welding. Other points are the same as those of the first embodiment (FIGS. 1 and 2).

FIG. 4 is a front view of a water channel forming member according to a third embodiment of the present invention. In this embodiment, as shown in FIG. 4, outer edge joints 17, 17 formed by projecting outwardly and vertically from outer edges of the left and right jacket communication paths 12, 12 and non-hollow portions 11, 11 at both upper and lower ends. 11 are seam-welded with each other, and non-hollow portions 11a
are fixed together by arc spot welding.
The front and rear wall connecting holes 16 formed in each non-hollow portion 11a
Are formed by forming a plurality of round holes at a predetermined pitch, and the other points are configured in the same manner as in the first embodiment (FIGS. 1 and 2). As described above, the non-hollow portions 11a
By fixing them together by arc spot welding, it is possible to prevent molding sand from entering between the non-hollow portions 11a to form a gap.

That is, when casting the channel forming member 10 into the head-side portion 4a of the continuous wall portion 4, the molding sand is pressurized into the jacket communication passage 12 and the cooling water channel 15 of the channel forming member 10 by, for example, a blow molding machine. In the case of press-fitting with air, if the non-hollow portions 11a and 11a are not fixed to each other, molding sand enters between the non-hollow portions 11a and 11a to form a gap. There is a problem that the thickness dimension of the water channel forming member 10 becomes large. However, by welding the non-hollow portions 11a and 11a together and fixing them together, such a problem can be solved and the accurate thickness dimension of the waterway forming member 10 can be maintained. .

FIG. 5 shows a fourth embodiment of the present invention.
It is a front view of the waterway formation member which concerns on the invention as described in. In this embodiment, as shown in FIG.
Is closed in a bag shape by the non-hollow portion 11b. That is, the upper and lower multi-stage non-hollow portions 11a are connected to the vertical non-hollow portions 11b at the center. Thereby, the waterway forming member 10 can be further thinned at the central portion where the thickness of the continuous wall portion 4 is the thinnest, and the continuous wall portion 4 can be made as thin as possible. Thereby, the thickness of the continuous wall portion 4 can be made thinner, and the pitch between the cylinder bores can be reduced.

As described above, the pair of left and right wedge-shaped cooling water passages 15 is partitioned by the vertical non-hollow portion 11b and formed in a bag shape with a closed end. 13 and 13 flows into the bag-shaped cooling water passage 15 and the jacket communication passage 12, and flows into the jacket communication passage 12.1.
2 to the head jacket 22 located above the continuous wall portion 4.

The upper edge 15b of each bag-shaped cooling water channel 15
Are formed at an upward slope outward in the left-right direction, so that the cooling performance is maintained at a high level. That is, even when the cooling water boils in each of the bag-shaped cooling water passages 15 and steam is generated, the steam moves upward along the upper edge 15b of each cooling water passage 15 formed in an upward slope, and the jacket communication passage is formed. 12 and escape to the head jacket 22. This keeps the cooling performance high. The front and rear wall connection holes 16 formed in each non-hollow portion 11a are formed as long holes, and the other points are configured in the same manner as the third embodiment (FIG. 4).

FIG. 6 is a front view of a water channel forming member according to a fifth embodiment of the present invention. In this embodiment, as shown in FIG. 6, outer edge joints 17, 17 formed by protruding outward from the outer edges of the left and right jacket communication paths 12, and the non-hollow portions 11 at the lower end are connected. Secured by seam welding. The front and rear wall connection holes 16 formed in each non-hollow portion 11a are formed with a single round hole, and the other points are configured in the same manner as the fourth embodiment (FIG. 5). I have.

[Brief description of the drawings]

1A and 1B show a channel forming member according to a first embodiment of the present invention, FIG. 1A is a perspective view of the channel forming member, and FIG. 1B is a cutaway right half of the channel forming member. Plan view, FIG. 1
(C) is a vertical sectional view taken along line CC in FIGS. 1 (A) and 1 (B).

FIG. 2 is a front view of a water channel forming member according to the first embodiment of the present invention.

FIG. 3 is a front view of a water channel forming member according to a second embodiment of the present invention.

FIG. 4 is a front view of a water channel forming member according to a third embodiment of the present invention.

FIG. 5 is a front view of a water channel forming member according to a fourth embodiment of the present invention.

FIG. 6 is a front view of a water channel forming member according to a fifth embodiment of the present invention.

7 shows a main part of a vertical multi-cylinder engine provided with a siamese cylinder cooling device according to the present invention, and FIG.
7A is a partial longitudinal sectional view, and FIG. 7B is a partial plan view of the cylinder block.

FIG. 8 is a longitudinal sectional view of a main part of a vertical multi-cylinder engine including the siamese cylinder cooling device according to the present invention.

9A shows a conventional example, FIG. 9A is a longitudinal sectional view of a main part of a siamese cylinder of a vertical engine, and FIG. 9B is a cross-sectional view taken along line BB in FIG. 9A. FIG. 9 (C) is a perspective view of a water channel forming member.

[Explanation of symbols]

1: Cylinder block, 2: Siamese cylinder, 3
... Cylinder, 3a ... Cylinder bore, 3b ... Cylinder outer peripheral surface, 4 ... Continuous wall portion, 4a ... Head portion of continuous wall portion, 5 ... Cylinder head fastening boss, 8 ... Cylinder jacket, 10 ... Water channel Forming member, 10a: metal plate, 11 / 11a: non-hollow part, 12: jacket communication path, 13: cooling water introduction part, 14: cooling water guide plate, 15 ...
Cooling water channel, 15b: upper edge of cavity, 16: front and rear wall connection hole, 17: outer edge joint, 22: head jacket.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akira Hayaya 64 Ishizukita-cho, Sakai City, Osaka Prefecture, inside Kubota Sakai Factory (72) Inventor Yasuichi Kamata 64, Ishizukita-machi, Sakai City, Osaka Prefecture Inside Kubota Sakai Factory ( 72) Inventor Masahiko Sugimoto 64, Ishizukita-machi, Sakai-shi, Osaka, Japan, inside Kubota Sakai Works, Ltd. (JP, A) JP-A-63-253156 (JP, A) JP-A-6-147002 (JP, A) JP-A-60-57758 (JP, U) JP-A-59-107946 (JP, U) Japanese Utility Model Application 59-68154 (JP, U) Japanese Utility Model Application 54-93605 (JP, U) Japanese Utility Model Application 57-117742 (JP, U) Japanese Utility Model Application 59-68155 (JP, U) (58) Int.Cl. ⁷ , DB name) F02F 1/00-1/42 F01P 3 / 02 B22D 19/08

Claims (6)

(57) [Claims] 1. A water channel forming member (1) is provided on a head-side portion (4a) of a continuous wall portion (4) of a siamese cylinder (2).
0), and the cooling water in the cylinder jackets (8) and (8) is supplied to the head jacket (22) located above the continuous wall portion (4) via the channel forming member (10).
In the cooling device for a siamese cylinder configured to be discharged to the side, the water channel forming member (10) includes a pair of left and right jacket communication paths (12) and (12) located in an upper half portion, and the jacket communication path (12). A pair of left and right cooling water introduction portions (13) and (13) which are located below the (12) and open toward the respective cylinder jackets (8) and (8), and the left and right jacket communication passages (12) and (12). Between the cooling water inlets (1
3) Between (13), a non-hollow portion (11) and a hollow portion forming a cooling water channel (15) alternately formed in upper and lower stages are provided, and each of the cooling water channels (15) is A cooling device for a Siamese cylinder, characterized in that the wedge-shaped tips are symmetrically configured so that the tips formed in a plan view face toward the center, and the wedge-shaped tips communicate with each other via a minute gap (S). . 2. A channel forming member (1) is provided on a head-side portion (4a) of a continuous wall portion (4) of a siamese cylinder (2).
0), and the cooling water in the cylinder jackets (8) and (8) is supplied to the head jacket (22) located above the continuous wall portion (4) via the channel forming member (10).
In the cooling device for a siamese cylinder configured to be discharged to the side, the water channel forming member (10) includes a pair of left and right jacket communication paths (12) and (12) located in an upper half portion, and the jacket communication path (12). A pair of left and right cooling water introduction portions (13) and (13) which are located below the (12) and open toward the respective cylinder jackets (8) and (8), and the left and right jacket communication passages (12) and (12). Between the cooling water inlets (1
3) Between (13), a non-hollow portion (11) and a hollow portion forming a cooling water channel (15) alternately formed in upper and lower stages are provided, and each of the cooling water channels (15) is A cooling device for a siamese cylinder, characterized in that the wedge-shaped tip is formed symmetrically so that the tip formed in a plan view faces the center, and the wedge-shaped tip is closed in a bag shape. 3. Each of said wedge-shaped cooling water passages (15)
The cooling device for a siamese cylinder according to claim 1 or 2, wherein at least an upper edge (15b) thereof is formed so as to be inclined upward in the left-right direction. 4. The water channel forming member (10) is formed with front and rear wall connecting holes (16) for connecting front and rear wall of the continuous wall (4) to each of the non-hollow portions (11a) formed in upper and lower tiers. The cooling device for a siamese cylinder according to any one of claims 1 to 3. 5. The water channel forming member (10) is formed by molding two metal plate-like bodies (10a) (10a) symmetrically by molding, and is formed at the outer edges of the left and right jacket communication paths (12) (12). The outer edge joints (17) and (17) are formed so as to protrude outwardly and vertically, and at least the outer edge joints (17) and (17) are fixed to each other to be integrally formed.
A cooling device for a siamese cylinder according to any one of the above. 6. The left and right sides of the head-side portion (4a) of the continuous wall portion (4) are formed so as to be continuous with a pair of left and right cylinder head fastening bosses (5), (5). The joint (17) is provided between the one cylinder (3) and the cylinder head fastening boss (5), and the other outer edge connection (17) is provided between the other cylinder (3) and the cylinder head fastening boss. The cooling device for a siamese cylinder according to claim 5, wherein the cooling unit is formed so as to be deflected toward one of the cylinders (3) and the other of the cylinders (3).