JP3232837B2 - V-type engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a V
It concerns the type engine.

[0002]

2. Description of the Related Art In a cooling system structure of a V-type engine,
Utilizing the fact that the left and right banks are offset in the direction of the crankshaft, a configuration has been proposed in which a drain pipe for cooling water is provided in a space created at the shaft end position (Japanese Utility Model Laid-Open No. 5-58824). ).

[0003] As shown in FIG.
A pipe 4 for cooling water introduction that wraps around from the radiator 1 in front of the engine to the rear end side and passes through the inside 7 of the bank and branches to the left and right banks 2 and 3, and one from the front end of each cylinder head of the left and right banks 2 and 3 A discharge merging pipe 6 merging at the position of the offset space 5 is provided so as to reduce the size of the cooling water pipe and effectively use the space.

[0004]

However, in the above-described conventional V-type engine, the flow of cooling water in the cylinder head is mainly in the direction in which the cylinders are arranged (crankshaft direction). There has been a problem that variations occur, leading to deterioration of engine performance. In order to improve the knock resistance of the combustion chamber, it is desirable to perform pre-cooling so that the water temperature on the intake side (inside the bank) 7 is always low, but this is insufficient with the conventional structure. Furthermore, the cylinder head in the V-type engine has different shapes on the left and right, so two types of molds are required.
There was a problem that the manufacturing cost was high.

Accordingly, the present invention provides a V-type engine which can make the engine compact by effectively utilizing the offset space, has no variation in cooling between cylinders, improves knock resistance, and can use the cylinder head in common to the left and right. It was invented to provide. Another related prior art described above is disclosed in Japanese Patent Application Laid-Open No. 60-2010.
No. 21 publication.

[0006]

According to the present invention, a cooling water discharge passage is provided along the outside of the bank for cooling water of each cylinder to flow from the intake port side to the exhaust port side and to be collected. In addition to extending to the offset spaces of both cylinder heads generated at the shaft ends due to the displacement of the bank in the crankshaft direction, a joining flow path extending in the axial direction connected to these cooling water discharge paths is provided inside the bank. .

[0007]

According to the above construction, the cooling water discharge passage cross-flows the cooling water flowing into each cylinder so as to pre-cool the intake side, and guides the cooling water to the inside of the bank at the position of the offset space. The merging channel causes the cooling water discharged from the left and right to flow along the inside of the bank and return to the radiator.

[0008]

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

FIGS. 1 to 3 show an embodiment of a V-type engine according to the present invention. This V-type engine has three cylinders 11, 12, 13, 14, 1
Left and right banks 17 and 18 provided with 5 and 16 are displaced by a predetermined distance in the crankshaft direction a,
Offset spaces S ₁ and S ₂ are formed at the front end of the left (L) cylinder head 19 and the rear end of the right (R) cylinder head 20, respectively. A cooling water discharge passage 2 for appropriately collecting the cooling water w of each of the cylinders 11...
The cooling water discharge passages 21 and 22 are connected to the cooling water discharge passages 21 and 22 so as to extend in the axial direction.

A pair of intake ports (intake ports) 24 and 25 and an exhaust port (exhaust port) are provided in the cylinder heads 19 and 20 for each cylinder 11.
26 and 27 and a plug hole 28 for a spark plug (not shown) are formed around the water jacket 2.
9 is appropriately formed. And each cylinder 11 ... 1
Radially outward on the exhaust port 26, 27 side of the cooling water w
Outlets 30 are formed respectively.

The cooling water discharge passages 21 and 22 extend along the outer sides of the cylinder heads 19 and 20 to form offset spaces S ₁ ,
Width toward the S ₂ is formed on a wide a tapered shape and is divided integrally by an outer wall 31, 32 provided to cover the outlet 30. That is, each cylinder 11 ... 16
The cooling water w is guided from the intake ports 24 and 25 to the exhaust ports 26 and 27, respectively, and then collected in the axial direction. The downstream sides of the cooling water drainage channels 21 and 22 are bent at the positions of the offset spaces S ₁ and S ₂ and extended in the width direction, and open toward the inside 33 of the bank. Outer wall 34 in offset space S ₁ , S ₂ ,
35 is an end face 36 of the other cylinder heads 20, 19,
37.

The merging passage 23 is defined by a pipe 40 extending from a discharge path end 38 of the right cylinder head 20 to a discharge path end 39 of the left cylinder head 19, and extends slightly obliquely with respect to the crankshaft direction a. ing. Then, the left cylinder head 19 is appropriately bent from a position where the left cylinder head 19 joins the discharge passage 21 to a radiator 41 provided at the front end of the engine, and is connected to one end thereof.

The cooling water w introduction path 42 is bent and extended from the other end of the radiator 41 to the center of the inside 33 of the bank, branches right and left from the center front end position, and branches right and left from the left and right banks 17 inside the front end of the cylinder block 43. , 18 respectively. Radiator 41 on the upstream side of introduction path 42
An in-line thermostat 44 is provided in the vicinity, and a main body 45 that senses the temperature of the cooling water w opens and closes a passage by operating a valve body 47 provided with a spring 46 so that the cooling water w is maintained at an appropriate temperature. Has become. A cooling water pump 48 is provided at a branch position of the introduction path 42 at the center of the front end, and a pulley 4 to which a driving force is transmitted from a crankshaft (not shown).
9, the impeller 51 attached to the shaft 50 is rotated to send the cooling water w to the left and right banks 17 and 18 under pressure.

Next, the operation of this embodiment will be described.

The cooling water w passing through the thermostat 44 in the introduction passage 42 is pumped by a cooling water pump 48 and enters the front ends of the left and right banks 17, 18 of the cylinder block 43, passing through the lower periphery of the cylinders 11. To the water jacket 29 of the cylinder heads 19, 20. The coolant flows in the direction transverse to the crankshaft direction a from the intake ports 24 and 25 on the inner side to the exhaust ports 26 and 27 on the outer side to cool the respective parts.
Exit to 22. The cooling water w discharged from each of the cylinders 11... 16 is collected outside the cylinder heads 19 and 20, and is guided forward in the left cylinder head 19 and backward in the right cylinder head 20, respectively.
33 through the offset spaces S ₁ and S ₂
Is returned to the radiator 41 by the combined flow path 23. In the radiator 41, heat is taken away by the blowing of a fan (not shown), and thereafter the heat is circulated to the left and right banks 17, 18 through the introduction path 42.

As described above, the cross-flow cooling is performed at the positions of the cylinders 11... 16 by the cooling water discharge passages 21 and 22 provided outside the bank. As a result, the intake air-fuel mixture is maintained at a low temperature, and the knock resistance of the combustion chamber is improved. Then, the temperature of the water between the cylinders 11 to 16 becomes uniform, and variations in cooling can be eliminated.

The offset spaces S ₁ , S ₂ of the cylinder heads 19, 20 are respectively connected to the cooling water discharge passages 21,
Since the engine is used for the engine 22, the engine can be made compact in the crankshaft direction a, and the left and right cylinder heads 19 and 20 have the same shape. Therefore, for example, by manufacturing the left cylinder head 19 shown in FIG. 2 and FIG. 3, if the left cylinder head 19 is reversed, it can be used as the right cylinder head 20, thereby reducing the number of manufacturing steps and the manufacturing cost. You.

Further, in this embodiment, since the cooling water discharge passages 21 and 22 along the outside of the cylinder heads 19 and 20 are tapered, it is possible to make the cooling water flow rates of the cylinders 11... 16 uniform. It is possible to promote cooling variation prevention.

In this embodiment, the cooling water discharge passage 2
Although the outer walls 1 and 22 are integrally defined around the cylinder heads 19 and 20 by the outer walls 31, 32, 34 and 35, they may be formed by separate pipes or the like. Also, the merging channel 23 may be formed straight on the crankshaft without being inclined.

[0020]

In summary, according to the present invention, the following excellent effects are exhibited.

A cooling water discharge path is provided for flowing and collecting the cooling water of each cylinder from the intake side to the exhaust side, and the cooling water discharge paths are respectively extended to the offset spaces of the left and right cylinder heads. Is maintained at a low temperature, knock resistance is improved, and variations in cooling between cylinders can be eliminated. In addition, the engine can be made compact and a common cylinder head can be used.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a V-type engine according to the present invention.

FIG. 2 is a horizontal sectional view of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a plan view showing a conventional V-type engine.

[Explanation of symbols]

11, 12, 13, 14, ₁₅ , 16 Cylinders 17, 18 Left and right banks 19, 20 Left and right cylinder heads 21, 22 Cooling water discharge passages 23 Combined passages 24, 25 Intake ports 26, 27 Exhaust ports 33 Inside banks S1, S ₂ Offset space a Crank shaft direction

────────────────────────────────────────────────── (5) References JP-A-58-118422 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F01P 3/02 F01P 11/04

Claims (1)

(57) [Claims] 1. A cooling water discharge passage for flowing cooling water of each cylinder from an intake port side to an exhaust port side to be collected is provided along the outside of a bank, and the cooling water discharge path is deviated in the crankshaft direction between the left and right banks. To extend into the offset space of both cylinder heads generated at the shaft end,
A V-type engine provided with a merging flow path extending in the axial direction connected to the cooling water discharge path inside the bank.