JPS6138332B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a V-type multi-cylinder engine with improved output.

In general, in multi-cylinder engines, as a means of improving output, the exhaust manifold is made into a dual exhaust, and two cylinders whose explosion interval is different by 360 degrees in terms of the rotation angle of the crankshaft are paired as a pair. It is known that the exhaust pipes are merged into one pipe. By adopting this configuration, the influence of exhaust pulsation in one exhaust pipe will not affect the flow of exhaust gas in the other exhaust pipe, allowing smooth release of exhaust gas and improving engine output. . Furthermore, since the in-line multi-cylinder engine has exhaust ports for each cylinder open on one side of the engine, the dual exhaust system can be easily applied.

On the other hand, in the conventionally known V-type four-cylinder engine, the first and third cylinders are placed in the right bank, and the second cylinder is placed in the left bank due to engine balance.
A cylinder and a fourth cylinder are respectively arranged, and the crank pins of each cylinder on one crankshaft are arranged at positions shifted in phase from each other when viewed from the end of the crankshaft, so that the piston of the first cylinder and the If the pistons of the four cylinders go down at the same time, the pistons of the second cylinder and the piston of the third cylinder go up at the same time, and the ignition order is changed to either the first cylinder - the second cylinder - the fourth cylinder - the third cylinder, or 1st cylinder - 3rd cylinder - 4th cylinder -
Since they are set in the order of the 2nd cylinder, the phase of the explosion interval between the 1st and 3rd cylinders on the right bank and between the 2nd and 4th cylinders on the left bank are both 180 degrees in crank angle. They are spaced at unequal intervals of 540° and 540°.

Therefore, in this V-type 4-cylinder engine, the cylinders with an explosion interval of 360° are the 1st cylinder, the 4th cylinder, and the 2nd cylinder.
cylinder and the third cylinder, while the V-type engine has an intake manifold between both the left and right banks, and the exhaust port for each cylinder is located on the outer surface of both banks, so this V-type 4 To apply the dual exhaust system to a cylinder engine,
The 1st and 4th cylinders, and the 2nd and 3rd cylinders are each paired, and the exhaust pipes of the pairs must be merged into one, but the exhaust ports of the 1st and 3rd cylinders must be placed on the right bank. The exhaust ports of the second and fourth cylinders open on the outer side of the left bank, so the exhaust pipe from the first cylinder's exhaust port and the exhaust pipe from the fourth cylinder's exhaust port open. , merging the exhaust pipe from the second cylinder's exhaust port and the exhaust pipe from the third cylinder's exhaust port into one exhaust pipe would make the structure of the exhaust pipe extremely complicated and long, so it would be difficult to connect the exhaust pipe from the second cylinder's exhaust port to the third cylinder's exhaust port. Not only do various restrictions arise in terms of layout, but the effects of the dual exhaust system cannot be fully obtained.

The present invention provides a V-type multi-cylinder engine in which the phases of the explosion intervals between the cylinders in both the left and right banks are set at equal intervals of 360° in terms of the rotation angle of the crankshaft, thereby reducing fluctuations in torque and rotational speed, and by providing a dual exhaust system. This method can be easily applied without reducing the effects of dual exhaust.

Next, a description will be given of drawings of an embodiment in which an example of the present invention is applied to a V-type four-cylinder engine. In the figure, 1 is a V-type engine main body, and the main body 1 is integrally provided in a V-shape from a crankcase 2 with a right bank 3 and a left bank 4 at an appropriate angle θ with respect to the vertical line. An oil pan 5 is provided on the lower surface, and inside the crankcase 2 there are oil pans 3 formed on the front, rear, and center portions of the crankcase 2.
A single crankshaft 9 is provided which is supported by three bearings 6, 7, and 8.

The right bank 3 is provided with a first cylinder 11 and a third cylinder 13, and the left bank 4 is provided with a second cylinder 12 and a fourth cylinder 14, and both left and right banks 3 and 4 are provided with:
The second cylinder 12 is shifted in the axial direction of the crankshaft 9 so that the fourth cylinder 14 is located between the first cylinder 11 and the third cylinder 13, and the fourth cylinder 14 is located behind the third cylinder 13. A flywheel 15 is provided at the rear output end 9', and a pulley 19 is provided at the front end 9'' for transmitting power to the cooling water pump 16 and alternator 17 via a belt 18, which are attached to the front surface of the left bank 4. ing.

In addition, exhaust ports 21, 22 in each cylinder,
23 and 24 are respectively opened on the outer surface of the engine body 1, and an intake manifold 27 is provided between both banks 3 and 4 for distributing intake air from an air cleaner 25 and an intake air mixer from a carburetor 26 to each cylinder. The engine body 1 is provided with a camshaft 29 which is rotatably driven by the crankshaft 9 at the base of both banks 3 and 4, parallel to the crankshaft 9, and a camshaft 29 which is rotatably driven from the camshaft 29 is provided at the rear of the right bank 3. The data distributor 28 is provided with a data distributor 28.
is set so that the ignition of each cylinder is in the order of 1st cylinder - 2nd cylinder - 3rd cylinder - 4th cylinder.

Between the front bearing part 6 and the central bearing part 8 of the crankshaft 9, there is a crank pin 41 into which the large end part 31' of the connecting rod 31 of the first cylinder 11 is fitted, and a crank pin 41 of the second cylinder 12. The large end 33' of the connecting rod 33 in the third cylinder 13 is fitted between the central bearing part 8 and the rear bearing part 7, and the crank pin 42 is fitted with the large end 32' of the connecting rod 32. and the crank pin 4 into which the large end 34' of the connecting rod 34 in the fourth cylinder 14 fits.
4 respectively, and the crank pin 41 of the first cylinder 11
and the crank pin 43 of the third cylinder 13 are in the same position, and when viewed from one end of the crankshaft 9, the vertical line -
The crank pin 42 of the second cylinder 12 and the crank pin 44 of the fourth cylinder 14 are at the same position from the vertical line - to the phase position of the inclination angle θ of the left bank 4. When the crankshaft 9 rotates in the direction of arrow A, the pistons of the first cylinder 11 and the third cylinder 13 in the right bank 3 simultaneously move downward and upward, and at this time, the pistons in the first cylinder 11 and the third cylinder 13 in the right bank 3 move downward and upward. The pistons in the second cylinder 12 and the fourth cylinder 14 are configured to move upward and downward at the same time with the phase of the explosion interval being 180 degrees out of phase with the right bank in terms of the rotation angle of the crankshaft. Both cylinders 11,
The exhaust pipes 51, 53 from the exhaust ports 21, 23 in the left bank 4 are connected to one main exhaust pipe 55. They are constructed so as to merge with the main exhaust pipe 56, respectively.

In addition, both main exhaust pipes 55 and 56 are connected to each exhaust pipe 5.
1, 53, 52, and 54 at a relatively long distance from the merging point of pipes 1, 53, 52, and 54, and connect them to one exhaust purification device (not shown). 55 and 56 may be connected to each exhaust gas purification device or to one exhaust gas purification device.

In this configuration, when the first cylinder 11 in the right bank 3 is in an explosive downward stroke as the crankshaft 9 rotates, the second cylinder 12 in the left bank 4 is in a compression upward stroke, and the explosive downward stroke in the second cylinder 12 is Following the first cylinder 11, the rotation angle of the first cylinder is 180
The third cylinder 13 is in the compression upstroke when the second cylinder 12 is in the explosion downstroke, and the third cylinder
The explosion downward stroke in the cylinder 13 follows the second cylinder 12 and is delayed by 180 degrees in terms of the rotation angle of the crankshaft, and when the third cylinder 13 is in the explosive downward stroke, the fourth cylinder 14 is in the compression upward stroke, and the fourth cylinder 14 is in the compression upward stroke. cylinder 14
The explosion downward stroke in the third cylinder 13 is delayed by 180 degrees according to the rotation angle of the crankshaft, and the explosion stroke in each cylinder is carried out after the third cylinder 13.
and the left bank 4, and the explosion intervals between the cylinders in both banks 3 and 4 are equal intervals of 360 degrees with respect to the phase of the crankshaft, so as in the conventional case, the explosion stroke in each cylinder is This is not done continuously between cylinders in the right bank and between cylinders in the left bank.

Furthermore, the pistons of the first cylinder 11 and the third cylinder 13 in the right bank 3 and the pistons of the second cylinder 12 and the fourth cylinder 14 in the left bank 4 move up and down at the same time, but the pistons in the first cylinder 11 and 3rd cylinder 13, the phase of the explosion interval is 360 degrees out of phase with the rotation angle of the crankshaft, so both cylinders 1
While the exhaust strokes of the second cylinder 12 and the fourth cylinder 14 exist between the exhaust strokes of the cylinders 1-13 and 13-11, the phase of the explosion interval of the second cylinder 12 and the fourth cylinder 14 is the same as that of the first cylinder. Since the exhaust strokes of the first cylinder 11 and the third cylinder 13 exist between the exhaust pipe strokes of both cylinders 12-14 and 14-12, which are shifted by 360 degrees in rotation angle, the first cylinder 11 in the right bank 3
and the third cylinder 13 in the second cylinder in the left bank 4.
The cylinder 12 and the fourth cylinder 14 are each made into a pair, and the first
The exhaust pipes 51 and 53 of the cylinder 11 and the third cylinder 13 are connected to one main exhaust pipe 55, and the exhaust pipes 52 and 54 of the second cylinder 12 and the fourth cylinder 14 are connected to one main exhaust pipe 56.
By merging with the cylinders, the dual exhaust system described above can be applied only to the cylinders in the right bank and the cylinders in the left bank.

Note that although the above embodiment was a case of a V-type 4-cylinder engine, the present invention is not limited to this, and the present invention is also applicable to a V-type engine with an integral multiple of 4 cylinders, that is, 8 cylinders or 12 cylinders. The phases of the intervals are out of 360° with respect to the rotation angle of the crankshaft.2
On the other hand, two cylinders in the left bank whose explosion interval phases are shifted by 360 degrees by the rotation angle of the crankshaft are used as a pair, and the cylinder pair in the right bank and the cylinder pair in the left bank are paired. The phase of the explosion interval is shifted by 180 degrees in terms of the rotation angle of the crankshaft so that when the cylinder pair in the right bank is on the upstroke, the cylinder pair on the left bank is on the downstroke, and both exhaust gases in the cylinder pair on the right bank are A similar application can be made by connecting the pipes to one main exhaust pipe and both exhaust pipes in the cylinder pair of the left bank to one main exhaust pipe.

As described above, according to the present invention, the explosion stroke of each cylinder in a V-type multi-cylinder engine is performed alternately for cylinders in both left and right banks, and the explosion intervals between cylinders in the right bank and between cylinders in the left bank are equal. Since the dual exhaust can be applied separately to the cylinder pair in the right bank and the cylinder pair in the left bank, when the exhaust manifold of a V-type engine is to be dual exhaust, it is possible to apply dual exhaust to the cylinder pair in the right bank and the cylinder pair in the left bank. The exhaust pipe does not have to be complicated or long because it straddles both the left and right banks, and the installation space for the exhaust pipe can be reduced, making the engine smaller and lighter. It has an effect that can be effectively achieved without reducing the

[Brief explanation of the drawing]

The drawings show an embodiment of the invention, and FIG. 1 shows a V-type 4
A plan view of the cylinder engine, Figure 2 is a front view of the engine in Figure 1, Figure 3 is an enlarged front view of the crankshaft,
Figure 4 is a cross-sectional view of Figure 3, and Figure 5 is a cross-sectional view of Figure 3.
FIG. 6 is a sectional view taken from - in FIG. 3; 1...Engine body, 2...Crankcase,
3... Right bank, 4... Left bank, 9... Crankshaft, 11... 1st cylinder, 12... 2nd cylinder, 13... 3rd cylinder, 14... 4th cylinder, 2
1, 22, 23, 24...exhaust port, 27...
Camshaft, 41...1st cylinder crank pin, 42...
...Second cylinder crank pin, 43...Third cylinder crank pin, 44...Fourth cylinder crank pin, 5
1, 52, 53, 54...exhaust pipe, 55, 56...
...Main exhaust pipe.

Claims (1)

[Claims] 1 In the right bank, two cylinders whose explosion intervals are out of phase by 360 degrees with respect to the rotation angle of the crankshaft are paired, while in the left bank, the phases of explosion intervals are out of phase with each other by 360 degrees with respect to the rotation angle of the crankshaft. The two cylinders in the right bank and the cylinder pair in the left bank are made into a pair, and the cylinder pair in the right bank and the cylinder pair in the left bank are
The phase of the explosion interval is shifted by 180 degrees by the rotation angle of the crankshaft so that when the cylinder pair in the right bank is in the upward stroke, the cylinder pair in the left bank is in the downward stroke.
A V-type engine characterized in that both exhaust pipes in a pair of cylinders on the right bank are configured to merge into one main exhaust pipe, and both exhaust pipes in a pair of cylinders on the left bank are configured to merge into one main exhaust pipe. .