JPS644053B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a V-type engine, more specifically a V-type engine in which a cooling water pump is installed approximately in the center of the front face of the cylinder block, that is, between both banks. Regarding type engines.

(Prior art) Conventionally, in V-type engines,
As shown in Japanese Patent Application No. 135228 (Japanese Patent Application No. 56-21145), an engine is known in which the cooling water pump is directly attached to the outer surface of the cylinder block, thereby reducing the size of the engine.

However, in such a V-type engine, the cooling water pump is installed offset to one side, so the lengths of the passages that supply cooling water to the water jackets of the left and right banks are different, and the There was a problem in that it was difficult to meet the requirement of uniformly supplying cooling water.

(Object of the Invention) The present invention has been made in view of the above points, and in addition to balancing the flow rate of cooling water to the left and right banks, it also balances the flow rate of cooling water to the left and right banks. The present invention provides a V-type engine with improved cooling performance by balancing the flow rates.

(Structure of the Invention) The present invention relates to an overhead camshaft (OHC) type V-type engine in which the cylinders of one bank are shifted in the axial direction of the crankshaft so that they are located between the cylinders of the other bank. In order to achieve the above-mentioned object, in the V-type engine, a cooling water pump is installed directly in the center of the front of the cylinder block, that is, in the part located between the two banks. , an outflow passage to each bank through which cooling water from the cooling water pump flows out is provided in the cylinder block between the front face and the cylinder closest to the front face in each bank, and each outflow passage is provided, The outer portion of the outflow passage is formed in a tapered shape toward the outer portion of the water jacket of each bank, and the tapered shape of each bank is formed asymmetrically to equalize the flow of cooling water. It is. In other words, a cooling water pump is installed approximately in the center of the front of the cylinder block to balance the flow rate to the left and right banks, and the effect of the difference in the length of the outflow passage due to the misalignment of the cylinders between the left and right banks is compensated for. The outflow passage is asymmetrically tapered to balance the flow rate between the inner and outer portions of the water jacket cylinder.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

In Figures 1 to 4, 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 of each bank 2, 3, which are hermetically sealed to the upper surface of the cylinder block 4, are provided with camshafts 10, 11, respectively, which camshafts 10, 11 are connected to the crankshaft 7 at their ends, This allows the camshafts 10, 11 and the crankshaft 7 to rotate simultaneously. That is, the camshaft 10,
Timing pulley 1 fixed to the end of 11
A timing belt 15 is wound around the crank pulleys 2 and 13 and a small-diameter crank pulley 14 fixed to the end of the crankshaft 7. 16,1
7 and 18 are idlers.

In addition, a transmission belt 20 wound around a large diameter crank pulley 19 fixed to the crankshaft 7 connects a pump pulley 22 of a cooling water pump 21 and an alternator 23, which are directly attached to the approximate center of the front surface 4a of the cylinder block 4. pulley 24
The cooling water pump 21 and the alternator 23 are thereby driven.

As shown in detail in FIGS. 2 to 4, the cooling water pump 21 is installed approximately in the center of the front surface 4a of the cylinder block 4, between the two banks 2 and 3, inside the timing belt 15. The housing 25 is directly attached to the cylinder block 4.
A pump chamber 26 is formed by a part of the wall surface of the cooling water pump 21 in the pump housing 25.
A rotating shaft 27 is rotatably supported via bearings 28 and 29. An impeller 30 that rotates within the pump chamber 26 is fixed to one end of the rotating shaft 27, and a pump pulley 22 and a fan 33 are attached to the other end via attachment members 31 and 32.

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 provided 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. A cooling water introduction passage 36 to the cooling water pump 21 is formed.

On the other hand, outflow passages 37 and 38 from which cooling water flows out from the cooling water pump 21 to the banks 2 and 3 are connected to the front surface 4a and the cylinder closest to the front surface 4a of each bank 2 and 3 within the cylinder block 4. 34 and 35, it is formed in an asymmetrical tapered shape to equalize the flow of cooling water. That is, as shown in FIG. 3, the discharge ports 21a, 21b of the cooling water pump 21 are formed at positions offset inward with respect to the axes of the cylinders 34, 35 of each bank 2, 3. In each outflow passage 37, 38, with respect to the cylinders 34, 35, the inner portions 39a, 40a of the water jackets 39, 40 are prevented from having a higher flow rate than the outer portions 39b, 40b. 39
b, 40b, the inner surfaces 37a, 38a of each outflow passage 37, 38 are arranged in a direction that substantially coincides with the axial direction of the crankshaft 7, and the outer surfaces 37b, 38b are arranged in a direction substantially consistent with the axial direction of the crankshaft 7.
(i.e., the outer portions of the outflow passages 37, 38 are tapered toward the outer portions 39b, 40b of the water jackets 39, 40 of each bank 2, 3. ), and the axial length of the crankshaft 7 of the outflow passage 37 is defined as the outflow passage 38
As a result, the opening angle of the outflow passage 37 is made larger than that of the passage 38, and both of them have an asymmetrical 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.

With the above configuration, since the cooling water pump 21 is installed approximately in the center of the cylinder block 4, that is, approximately in the center of the left and right banks 2 and 3, the flow rate of cooling water to the left and right banks 2 and 3 is reduced. is almost uniform.

Moreover, the discharge ports 21a, 21 of the cooling water pump 21
Due to its directivity, the amount of cooling water flowing out from b is suppressed in the outflow passages 37, 38 from flowing into the inner portions 39a, 40a of the cylinders 34, 35, and flows to the outer portions 39b, 40b. As a result, the flow rates in the inner portions 39a, 40a and the outer portions 39b, 40b of the water jackets 39, 40 are also substantially uniform.

Therefore, the cooling water flows almost uniformly in each part of the water jackets 39, 40 of each bank 2, 3, thereby uniformly cooling them.

In the above embodiment, the pump chamber 26 of the cooling water pump 21 is formed by the front surface 4a of the cylinder block 4 and the pump housing 25.
The pump chamber may be formed by the pump housing 25 and a plate member, and the plate member may be in contact with the front surface 4a of the cylinder block 4.

(Effects of the Invention) As described above, in the present invention, since the cooling water pump is installed approximately at the center of the front surface of the cylinder block, the flow rate of cooling water to each bank is balanced, and the cooling water pump Since the outflow passage through which water flows out has an asymmetrically tapered shape, the flow rate to the inner and outer portions of the water jacket cylinder is balanced, thereby improving cooling performance. Furthermore, in each bank, the lead-out passage is formed between the front face of the cylinder block and the cylinder closest to the front face of the cylinder block, so that the overall length of the engine does not become long.

[Brief explanation of drawings]

The drawings illustrate embodiments of the invention.
The figure is a schematic front view of a V-type engine, Figure 2 is a partial sectional view of the same, Figure 3 is a sectional view taken along the - line in Figure 1, and Figure 4 is a sectional view taken along the - line in Figure 1. . 1... V-type engine, 2, 3... Bank, 4...
...Cylinder block, 4a...Front, 34, 35
...Cylinder, 37, 38...Outflow passage.

Claims (1)

[Claims] 1. In a V-type engine that is arranged offset in the axial direction of the crankshaft so that the cylinders of one bank are located between the cylinders of the other bank, a cooling water pump is installed approximately in the center of the front face of the cylinder block, and an outflow passage to each bank through which cooling water from the cooling water pump flows out is provided in the cylinder block between the front face and the cylinder closest to the front face in each bank;
Each outflow passage is formed in a tapered shape in which the outer part of the outflow passage is directed toward the outer part of the water jacket of each bank, and the taper shape of each bank is formed asymmetrically to equalize the flow of cooling water. A V-type engine characterized by