JPH0222216B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention is used in the technical field of V-type engines installed in automobiles, etc., and in particular at the ends of the cylinder block and approximately at the center of the left and right banks. This relates to a V-type engine equipped with a water pump.

(Prior Art) Conventionally, in a V-type engine installed in an automobile, etc., a water pump is attached to the longitudinal end of the cylinder block, for example, as disclosed in Japanese Patent Laid-Open No. 57
This is known from, for example, Japanese Patent No.-135228.

(Problem to be Solved by the Invention) However, the water pump is attached to the longitudinal end of the cylinder block and approximately in the center of the left and right banks, so that the amount of water supplied to the water jackets of the left and right banks is equalized. I couldn't find anything that took this into account.

In other words, the cylinders in each cylinder block of the left and right banks in a V-type engine are moved back and forth because the crank pin that connects the large ends of the connecting rods of the pistons fitted in these cylinders is shifted back and forth. It's shifted. Therefore, if the water pump is installed at the longitudinal end of the cylinder block and approximately in the center of the left and right banks, and the cooling water is distributed to the left and right water jackets respectively, the water pumps for the left and right water jackets Among the side opening ends, one has a small distance from the cylinder liner outer wall surface, and the other has a large distance. If we look at the side where this distance is small, the distance between the outer wall surface of the cylinder liner and the edge of the opening end becomes small, the flow resistance as a cooling water passage becomes large, and the amount of water flowing to the left and right water jackets decreases. are no longer equal. In this case, it is not desirable to separate the water pump mounting surface from the cylinder liner in order to increase the above-mentioned distance, since this increases the overall length of the engine as a whole. Furthermore, there is a problem in that it is troublesome to make the water pump mounting surface stepped on the left and right sides in order to make the distance between the left and right sides the same.

In this invention, when the water pump is installed approximately in the center of the left and right banks at the longitudinal ends of the V-type engine, the overall length of the entire engine is not increased and no troublesome machining is required.
To provide a V-type engine in which the distribution of cooling water to water jackets of left and right banks is uniform.

(Means for Solving the Problem) In order to achieve the above object, in the present invention, a water pump is attached to the longitudinal end of the cylinder block, and cooling water is supplied to the water jackets of the left and right banks of the cylinder block. The target is a V-type engine that distributes the The water pump is installed approximately at the center of the left and right banks. The discharge port for each bank of the water pump is formed at a position offset inward with respect to the axis of the cylinder of each bank. Among the water pump side opening ends of the water jackets for each bank, the opening area of the water pump side opening end of the bank having a smaller distance from the outer wall surface of an adjacent cylinder is larger than that of the other bank. It is set. Each outflow passage extending from the water pump side opening end of each bank to the water jacket is inclined outward with respect to the axial direction of the crankshaft so that its outer surface follows the outer surface of the adjacent cylinder, and The length of the outflow passage in the crankshaft axial direction of the bank having a larger distance from the adjacent cylinder outer wall surface is longer than that of the other bank.

(Function) Accordingly, in the present invention, when the water pump is installed at the longitudinal end of the cylinder block and at the center of the left and right banks, the water pump side opening ends of the water jackets of the left and right banks are connected to each other. Because the area of the opening end of the bank with the smaller distance from the outer wall of the cylinder is larger than that of the other bank, even if the water pump is installed close to the cylinder liner, the area of the open end of the bank with the smaller distance from the outer wall of the cylinder is larger than that of the other bank. The distance between the open end of the cylinder liner and the outer wall surface of the cylinder liner is small, and it is possible to prevent flow resistance from becoming large.

Furthermore, by forming the discharge ports of each bank of the water pump inwardly with respect to the axis of the cylinder of each bank, the flow of cooling water in the axial direction of the crankshaft can be directed to the water jacket as much as possible. can be made uniform between the inner and outer parts of the cylinder. Moreover, each outflow passage extending from the water pump side opening end of each bank to the water jacket is inclined outward with respect to the axial direction of the crankshaft so that the outer surface thereof is along the outer surface of the adjacent cylinder. In addition, by forming the outflow passage of the bank having a larger distance from the adjacent cylinder outer wall surface in the crankshaft axial direction to be longer than the outflow passage of the other bank, the water jacket can be improved. It is possible to prevent the flow rate in the inner part from becoming larger than the flow rate in the outer part, and it is possible to equalize the flow rate between the inner part and the outer part of the water jacket in each bank.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. The left and right directions in FIG. 2 are referred to as longitudinal directions.

In Figures 1 to 5, 1 is an OHC type V-type engine having left and right banks 2 and 3 arranged in a V-shape, 4 is its cylinder block,
An oil pan 5 is attached to the bottom surface. A crankshaft 7 is provided in a crankcase 6 constructed below the cylinder block 4.

The cylinder heads 8, 9, which are hermetically sealed to the upper surface of the cylinder block 4 of each bank 2, 3, are provided with camshafts 10, 11, respectively, which camshafts 10, 11 are connected at their ends to the crankshaft and thereby Then, camshaft 1
0, 11 and the crankshaft 7 can rotate synchronously. That is, the camshaft 10,1
Timing pulley 1 fixed to the end of 1
A timing belt 15 is wound around the crank pulleys 2 and 13 and a crank pulley 14 fixed to the end of the crankshaft 7. 16, 17, 18
is an idler.

Further, a transmission belt 20 wound around a large-diameter crank pulley 19 fixed to the crankshaft 7 connects to a water pump 21 that is directly attached to approximately the center of the front surface 4a of the longitudinal end of the cylinder block 4. The water pump 21 and the alternator 23 are wound around the pump pulley 22 and the pulley 24 of the alternator 23, thereby driving the water pump 21 and the alternator 23.

The water pump 21 is shown in FIGS.
As shown in detail in the figure, a pump housing 25 is located approximately in the center of the front surface 4a of the cylinder block 4, between the two banks 2 and 3, and inward of the rotating timing belt 15. A pump chamber 26 is formed by a part of the wall surface of the cylinder block 4, and a rotation shaft 27 of the water pump 21 is attached to the pump housing 25.
is rotatably supported via bearings 28 and 29. One end of this rotating shaft 27 has the pump chamber 2
An impeller 30 rotating inside the pump 6 is fixed to the pump pulley 22 at the other end via mounting members 31 and 32.
and a fan 33 are attached.

In the cylinder block 4, the cylinders 34 of one bank 2 are connected to the cylinders 34 of the other bank 3.
5 and is shifted in the axial direction of the crankshaft 7. A radiator (not shown) is located between the front surface 4a and the cylinder 34 closest to the cylinder block 4 of the one bank 2, which is the side where the cylinder 34 is further away from the front surface 4a of the cylinder block 4. An introduction passage 36 for introducing cooling water into the water pump 21 is formed.

On the other hand, outflow passages 37 and 38 through which cooling water flows out from the water pump 21 are located within the cylinder block 4 between the front surface 4a and the cylinders 34 and 35 closest to the front surface 4a in each bank 2 and 3. It is formed into an asymmetrical tapered shape. That is, as shown in FIG.
Since the discharge ports 21a and 21b of each bank 2 and 3 of 1 are formed at positions offset inward with respect to the axes of the cylinders 34 and 35 of each bank 2 and 3,
In each outflow passage 37, 38, the cylinder 34,
35, the inner parts 39a, 40a of the water jackets 39, 40 are the outer parts 39b, 40b.
The inner part 39 prevents the flow rate from increasing.
In order to make the flow rate substantially uniform between the flow rates between the flow passages 37a and 40a and the outer portions 39b and 40b, the inner surfaces 37a and 38a of the respective outflow passages 37 and 38 are arranged in a direction that substantially coincides with the axial direction of the crankshaft 7, and the outer surfaces 37b and 38b are
is inclined outward with respect to the axial direction of the crankshaft 7 along the outer surfaces of the cylinders 34 and 35, and the crankshaft 7 of the outflow passage 37 is
is formed to have a longer axial length than the outflow passage 38,
Thereby, the opening angle of the outflow passage 37 is adjusted to the opening angle of the outflow passage 37.
8, and both have an asymmetric tapered shape.

As mentioned above, the reason why the outflow passage 37 on the bank 2 side is longer in the axial direction of the crankshaft 7 than the passage 38 on the bank 3 side is because the cylinder 34 at the front of bank 2 is located at the front of the bank 3. Although it is shifted rearward than the cylinder 35 of 2.
This is to make the volumes of the water jackets 39, 40 in front of the two cylinders 34, 35 substantially the same. This prevents the volume of the water jacket 39 in front of the cylinder 34 of the bank 2 from increasing unnecessarily.

Furthermore, the water pump side opening end 39c of the water jacket 39, 40 for each bank 2, 3,
Among the opening ends 40c, the opening end 40c has a smaller distance from the liner outer wall surfaces 34a and 35a of the adjacent cylinders 34 and 35, that is, the opening area _S1 of the opening end 40c is as follows:
It is formed larger than the opening area _S2 of the other opening end 39c, and both water jackets 39, 40
The resistance to the flow of cooling water at the cooling water inlet part of the cooling water is equalized. That is, as shown in FIG. 4, the opening end 39c is circular, whereas the opening end 40c is formed into an oval shape extending further outward.

Therefore, the V-type engine 1 configured as above
In this case, the water pump 21 is installed almost in the center of the cylinder block 4, and the flow resistance of the cooling water inlets of the left and right water jackets 39, 40 is made equal, so that the cooling water is distributed evenly to the left and right banks 2, 3. is not only distributed, but also the outflow passage 37,
38, cooling water is distributed in a well-balanced manner to the inner portions 39a, 40a and outer portions 39b, 40b of the cylinders 34, 35 of the water jackets 39, 40, achieving good cooling performance.

In the embodiment described above, the opening end 40c has a horizontally elongated shape, but it may have another shape. Also, the water pump may be installed approximately in the center of the left and right banks. Further, a pump chamber 26 of the water pump 21 is formed by the front surface 4a of the cylinder block 4 and the pump housing 25.
and a plate member, and the plate member may be brought into contact with the front surface 4a of the cylinder block 4. Furthermore, the engine itself is not limited to use in automobiles, and of course may be used in other applications.

(Effects of the Invention) As described above, the present invention has the water pump attached to the longitudinal end of the cylinder block and the center of the left and right banks, and the water pump side opening ends of the water jackets of the left and right banks.
Since the area of the open end of the bank with the smaller distance from the adjacent cylinder liner outer wall surface is larger than that of the other bank, the water pump can be installed fairly close to the cylinder liner to reduce the overall length of the engine. Even if the length is shortened, the amount of cooling water for the left and right water jackets will not be biased and will be equal, and there is no need to make the structure particularly complicated. Furthermore, the discharge port for each bank of the water pump is formed at a position offset inwardly with respect to the axis of the cylinder of each bank, and each outflow passage is inclined so that its outer surface follows the outer circumferential surface of the cylinder. At the same time, the length of one outflow passage is longer than the other, so the flow rate between the inner and outer parts of the water jacket in each bank can be made uniform, thereby ensuring good cooling performance. It can produce unique and remarkable effects.

[Brief explanation of drawings]

The drawings show a V-type engine according to an embodiment of the present invention; FIG. 1 is a schematic front view, FIG. 2 is a partially sectional side view, FIG. 3 is a sectional view taken along the line -- in FIG. 1, and FIG. Figure 3 is a cross-sectional view of Figure 1. Figure 5 is a cross-sectional view of Figure 1.
FIG. 1... V-type engine, 2, 3... Bank, 4... Cylinder block, 4a... Front (of the end of the cylinder block), 21... Water pump, 21a, 21
b...Discharge port, 34, 35...Cylinder, 37, 38
...Outflow passage, 37b, 38b...Outer surface, 39, 4
0... Water jacket, 39a, 40a... Inner part, 39b, 40b... Outer part, 39c, 40
c...Water pump side opening end, 34a, 35a...
Liner outer wall surface.

Claims (1)

[Scope of Claims] 1. A V-type engine in which a water pump is attached to a longitudinal end of a cylinder block and distributes cooling water to water jackets of left and right banks of the cylinder block, wherein the water pump has the following features: The water pump is installed approximately in the center of the left and right banks, and the discharge port of each bank of the water pump is formed at a position offset inward with respect to the axis of the cylinder of each bank, Of the water pump side opening ends of the water jacket, the opening area of the water pump side opening end of the bank having a smaller distance from the outer wall surface of the adjacent cylinder is set to be larger than that of the other bank. , each outflow passage extending from the water pump side opening end of each bank to the water jacket is inclined outward with respect to the axial direction of the crankshaft so that its outer surface follows the outer surface of the adjacent cylinder, and , a V-type engine characterized in that the length of the outflow passage in the crankshaft axial direction of the bank having a larger distance from the adjacent cylinder outer wall surface is longer than that of the other bank. .