JPH0255828A - Four-cycle engine - Google Patents

Abstract

PURPOSE:To contrive the improvement of intake efficiency by providing a chamber, connecting each combustion chamber to communicate, between adjacent cylinders and opening this chamber to an intake port. CONSTITUTION:Recessed parts 4b, forming a combustion chamber of each cylinder, are provided in a cylinder head 4, and a recessed part 4e is formed between the adjacent recessed parts 4b. A chamber, formed by the recessed part 4e, is opened to an intake port 4f, when intake is performed, a mixture is additionally supplied to each combustion chamber through the chamber formed by the recessed part 4e. In this way, intake efficiency can be improved.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a four-stroke engine.

[Conventional technology]

Recent 4+J cycle engines tend to have more valves, and by increasing the number of pulps in each cylinder and increasing the opening area of the pulps, the air-fuel mixture intake efficiency is increased, thereby increasing output. There is.

[Problem to be solved by the invention]

By the way, in a four-stroke engine equipped with a normal cylindrical piston, the mechanism becomes extremely complicated, so the maximum number of intake valves per cylinder is three, and efforts are being made to further improve intake efficiency. That is difficult.

In order to solve this problem, a four-stroke engine has conventionally been provided in which a piston is configured in an elliptical shape and four intake valves are arranged in parallel in the long diameter direction of this ellipse.

However, in the above-mentioned engine, since the piston has an elliptical shape, it is disadvantageous in terms of balance and thermal strain compared to a cylindrical piston, and the machining of the piston and the like is complicated.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a four-stroke engine that is advantageous in terms of balance and thermal strain and can improve output through easy machining operations.

[Means to solve the problem]

In the four-stroke engine according to the present invention, a chamber is provided between adjacent cylinders that allows the combustion chambers of these cylinders to communicate with each other, and an intake port is opened in this chamber. A valve is installed to open and close the space between the two.

(Operation) According to the above configuration, suction efficiency can be improved using the cylindrical piston.

(Example) Hereinafter, the present invention will be described in detail based on drawings showing examples.

FIGS. 1 to 4 conceptually show the main parts of a 4-stroke 2-engine according to the present invention, and exemplify a DOL-IC type engine mounted on a motorcycle.

As shown in FIG. 245 and FIG.
It is equipped with a pair of pistons 1, 1. The pistons 1, 1 are
They have a cylindrical shape of the same size, and are each fitted into a sleeve 13.3 embedded in the cylinder tab [cock 2]. The sleeves 3, 3 are cylindrical, and the upper ends of their circumferential surfaces are connected to each other, and have a substantially figure 8 shape on the cylinder head mounting surface 2a of the cylinder block 2. Although not clearly shown in the drawings, the pair of pistons 1, 1 are each connected to crank bins of the same phase on the crankshaft via connecting rods.

On the other hand, as shown in FIG. 1, the cylinder head 4 used in this engine has a cylinder block mounting surface 4a.
It has a pair of recesses 4b, 4b.

The recesses 4b, 4b are formed at positions corresponding to the pistons 1, 1 in the cylinder block 2, respectively, and two ends of each of the intake bows 1 and 4C and the two ends of the Exith 1 boat 4d are communicated inside the recesses 4b, 4b. There is. These intake ports 4c, 4c, 4c, 4c
and exhaust boats 4d, 4d, 4d, 4d,
Recessed portion 4b.

One row of openings in each cylinder 4b are arranged along the longitudinal direction of the cylinder head 4, and the other ends of each opening are opened in opposing side walls of the cylinder head 4. In addition, as is clear from the figure, the intake ports 4c, 4c, 4c.

4C has its loose ends merged into the respective recesses 4b, 4b, and carburetors 5, 5 of the same diameter are connected to each of the recesses 4b.

Furthermore, two intake valves 6 and two exhaust valves 7 are provided in each of the recesses 4b, 4b. The intake valve 6.6.6.6 is the intake valve t-4c,
4. The openings of the valves c, 4c, and 4c are disposed at positions that close the openings of the valves, and are opened and closed at the same time by an intake valve camshaft (not shown) disposed in the cylinder head 4. On the other hand, the exhaust valves 7.7, 7.7 are the intake valves 6.
6°Similar to 6.6, the above exhaust boat 4d.

4d, 4d, and 4d, and are opened and closed at the same time by an exhaust valve camshaft (not shown).

On the other hand, the cylinder head 4 has a recess 4e in the cylinder block mounting surface 4a. This recessed portion 4e serves as the intake valve 6.6 between the pair of recessed portions 4b, 4b.
・The recesses 4b and 4b are formed on the side and communicate with each other.

Further, one end of the intake port 4f is communicated with the inside of the recess 4e. Intake bow! ~4f is 1
Intake bow 1-4c communicating with the pair of recesses 4b, 4b
, 4c, 4c, 4c, and the other end thereof is the intake port 4c in the side wall of the cylinder head 4.

It opens between the openings 4c, 4c, and 4c. As is clear from the figure, the intake ports 4G, 4C, and 4C are provided in the opening of the side wall of the cylinder head 4 in the intake port 4f.

A carburetor 8 having a smaller diameter than the carburetors 5, 5 connected to 4C is connected.

Further, an intake valve 9 is disposed in this recess 4e. As shown in FIG. 4, the intake valve 9 is arranged in a position to close the opening in the intake port 4, and is connected to an intake valve camshaft that opens and closes the intake valve 6. 10, these intake valves 6.6, 6.6 are opened and closed at the same time. In addition,
Reference numeral 11 in FIG. 4 is a swing arm type hydraulic lash adjuster, which is provided not only at the intake valve 9 but also at the intake valves 6.6, 6.6 and the exhaust valves 7.7, 7°7. There is. Also, reference numeral 12 in FIGS. 3 and 4
is an intake valve 9 provided at the connecting portion of the sleeves 3, 3.
This is a valve recess for use.

Further, reference numeral 13 in FIGS. 1 and 2 is a spark plug mounting hole.

In the above engine, when the cylinder head 2 is installed on the cylinder block 4 as shown in FIG.
A combustion chamber 14.14 is defined by the recesses 4b, 4b, the inner circumferential surfaces of the sleeves 3, 3, and the upper surfaces of the pistons 1, 1 located at the top dead center, respectively, and the recess 4e and the connecting portion of the sleeves 3, 3. A chamber 15 is defined between the combustion chambers 14.14, which allows these combustion chambers 14.14 to communicate with each other.

Now, the intake valve 6.6°6.6 in the combustion chamber 14.14
is actuated by the intake valve camshaft 10, the intake ports 4c, 4c, 4c, 4c are opened and the pistons 1, 1 are moved downward, so that the inside of the combustion chamber 14, which is in a negative pressure state and The above intake port 4G into the sleeves 3, 3.

The air-fuel mixture is sucked in from the carburetors 5, 5 through 4c, 4c, 4c. At this time, in the chamber 15 communicating with the combustion chamber 14.14, the intake valve 9 is operated at the same time as the intake valves 6.6 and 6.6, the intake port 4f is opened, and the pistons 1 and 1 are opened. It is in a negative pressure state due to the downward movement of. Therefore, the combustion chamber 14.
14 and into the sleeves 3, 3, the air-fuel mixture is also drawn from the carburetor 8 via the intake port 4f and the air 15.

In addition, in the above embodiment, the combustion chambers 14 and 14 of the two cylinders are
Although the combustion chambers of three or more cylinders may be communicated with each other through the chamber 15, in the present invention, the combustion chambers of three or more cylinders may be communicated with each other.

Moreover, although the case is illustrated in which there is one set of cylinders communicating with the combustion chambers 14, 14, the engine may include a plurality of sets of cylinders. In addition, the DO mounted on motorcycles
Although the HC type engine is illustrated, it is not necessarily limited to these.

Further, in the above embodiment, one intake port 4f is opened in the chamber 15, and one intake valve 9 is disposed in the similar character 15, but in the present invention, the intake port 4f and the intake valve 9 may be plural. Furthermore, although only the intake port 4f is opened in the chamber 15 and only the intake valve 9 is disposed, in the four-stroke engine according to the present invention, in addition to these, an exhaust boat is opened in the chamber 15, Additionally, an exhaust valve may be provided.

[Effects of the Invention] As described above, according to the four-stroke engine according to the present invention, suction efficiency can be improved by using a cylindrical piston, which is advantageous for balance and thermal distortion, and is easy to process. You can improve your output through work.

[Brief explanation of the drawing]

FIG. 1 is a bottom view conceptually showing a cylinder head section applied to a four-stroke engine according to the present invention, and FIG. 2 is a cross-sectional view conceptually showing main parts of a four-cycle engine according to the present invention. A side view, FIG. 3 is a perspective view conceptually showing a cylinder block section applied to a four-stroke engine according to the present invention, and FIG. 4 is an enlarged sectional view taken along the line IV-mV in FIG. 2. 4f...Intake port, 9...Valve, 14.
...Combustion chamber, 15...chamber.

Claims (1)

[Claims] A chamber is provided between adjacent cylinders to allow the combustion chambers of these cylinders to communicate with each other, an intake port is opened in this chamber, and a valve is provided in the chamber to open and close between the chamber and the intake port. A 4-stroke engine with the following features.