JPS5996432A - Valve unit for supercharging cylinder of supercharging type multi-cylinder internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve the compression ratio as well as the volumetric efficiency in a supercharging cylinder by inserting a valve-fixing plate on which a nonreturn type suction valve and discharge valve are fixed between a cylinder head and a cylinder block for reducing a clearance space. CONSTITUTION:A disk-shaped valve-fixing plate 22 on which a nonreturn type suction valve 20 and a nonreturn type discharge valve 21 are fixed against a suction port 13 and a discharge port in a supercharging cylinder 3, is inserted between a cylinder head 23 and a cylinder block 24. In the first compression stoke by the rise of a piston 25 in the second cylinder 3, the third cylinder 4 is in the suction stroke, and in the next compression stroke of the second cylinder, the first cylinder 2 is in the suction stroke. The first cylinder 2 and the third cylinder 4 are alternatively brought into the suction stroke.

Description

Detailed Description of the Invention The present invention provides a multi-cylinder internal combustion engine in which some of the cylinders are configured as supercharging cylinders for compressing intake air. The present invention relates to a valve device for sucking and discharging air in a supercharging cylinder.

A multi-cylinder internal combustion engine in which some of the cylinders are used as supercharging cylinders for other combustion cylinders is disclosed in Japanese Patent Publication No. 55-27218 and Japanese Patent Application Laid-open No. 52-76.
This is proposed by Japanese Patent No. 517. The supercharging cylinder in this type of supercharged internal combustion engine requires an intake valve that opens when air is taken in and closes when air is discharged, and a discharge valve that closes when air is taken in and opens when air is discharged. And,
In both of the above-mentioned publications, the intake valve is a check valve type, and is provided in the middle of the intake passage to the supercharging cylinder, while the discharge valve is also used as an intake valve for another combustion cylinder. ing.

However, in the prior art described above, the cylinder volume at the end of compression when the piston of the supercharging cylinder reaches top dead center and at the time when the piston starts suction on the downward stroke from top dead center is limited to the cylinder volume for supercharging. The volume of the intake passage from the cylinder to the intake valve and the volume of the discharge passage from the supercharging cylinder to the intake valve in the other combustion cylinder are added, so that the volume at the end of compression and at the beginning of intake is Since the gap volume will increase significantly, the formula ε= (Vs +V
c) The compression ratio expressed as /Vc (where Vs is the stroke volume of the piston in the supercharging cylinder and VC is the gap volume) cannot be increased, and the volumetric efficiency of the supercharging cylinder is low. The efficiency of suction into the combustion cylinder was low.

The present invention provides a multi-cylinder internal combustion engine in which some of the plurality of cylinders are configured as supercharging cylinders for other combustion cylinders as described above. By providing the suction valve and discharge valve in the supercharging cylinder in a state where they can be easily assembled and disassembled, the gap volume can be reduced. , the compression ratio and volumetric efficiency of the supercharging cylinder have been improved.

The following describes an example in which the present invention is applied to a three-cylinder engine.
The third cylinder (4) is a four-cycle combustion cylinder, and the second cylinder (3) is a two-stroke supercharging cylinder. 4) The number cylinder has an intake boat (7) (8) with intake valve (5) (6) and an exhaust boat (01) α with exhaust valve (9) 00), and the second cylinder (3) has an intake boat ( 14 and discharge boat (14
), and the pistons of the first cylinder (2) and the third cylinder (4) move up and down simultaneously in the same phase, but the pistons of the second cylinder (
3) The piston moves up and down in the exact opposite direction to the pistons in the first and third cylinders, at a crank angle of 180 degrees. On the other hand, the first air cycle (2) and the third air cycle (4) are arranged so that the ignition order is cranked so that when the first cylinder (2) is on the explosion stroke, the third cylinder (4) is on the intake stroke. There is a 360° shift in the angle, and during the first compression stroke of the second cylinder (3), the third
When the cylinder (4) is in the intake stroke and the next compression stroke of the second cylinder (3), the first cylinder (2) is also in the intake stroke, and the stroke volume in the second cylinder (3) is the same as that in the first and second cylinders. 3 cylinders (2)
(4) is set to the volume required for supercharging.

00 is an air cleaner for intake, and the air cleaner a is connected to the intake bow 1-(of the second cylinder (3) through the passage a@).
1■, while the discharge bow 1- of the second cylinder (3)
(14) is the surge tank 071 for eliminating pulsation and the vaporizer θ
8) The intake boat (7) of the first cylinder (2) and the third
Connect to the intake boat (8) of the cylinder (4).

Then, the suction boat (13) in the second cylinder (3)
and a check valve type suction valve Q0 for the discharge boat (14).
Similarly, when installing a check valve type discharge valve (2!η), the second cylinder (3) is equipped with a disc-shaped valve mounting plate (A) between the cylinder head (C) and the cylinder block (C). A suction chamber (1) connected to the suction port 1.
A discharge chamber (A) communicating with the discharge boat 04) is formed, while a suction valve extending into the suction chamber (C) and a discharge valve extending into the discharge chamber (C) are formed on the valve mounting plate (A). It is made by attaching.

In addition, the exhaust boat 0 of the first and third cylinders (2) (4)
An exhaust manifold (C) is connected to υ@.rL1 The mass of the reciprocating part and the mass of the rotary part in the first cylinder (2) and the third cylinder (4) are the same, and the mass is located between them. The mass of the reciprocating motion part and the mass of the rotary motion part in the second cylinder (3) are the mass of the reciprocating motion part and the mass of the rotary motion part of the other cylinders, that is, the first cylinder (2) or the third cylinder (4). By setting it approximately twice as much, the balance between the reciprocating mass and the rotating mass is maintained.

In this configuration, the piston (
During the first compression stroke due to the upward movement of c), the third cylinder (
4) is the intake stroke, and the first cylinder (2) is in the intake stroke when the second cylinder (3) is on the next compression stroke, so the air is drawn into the second cylinder (3) from the air cleaner 0, and the relevant 2nd Qi @(
3) The pressurized air is compressed in the first cylinder (2).
) and the third cylinder (4), and in this case, the air is injected into the first cylinder (2) and the third cylinder (4) alternately. If a fuel supply means such as 08) is provided downstream of the second cylinder (3) for supercharging, the fuel supplied by the carburetor 08) is
It is sent to the first cylinder (2) and third cylinder (4) for combustion without passing through the second cylinder (3) for supercharging.

And the piston (c) in the second air for supercharging @ (3)
During the suction stroke of the downward motion? During the compression stroke of the upward motion of the piston (c), the suction valve (21) closes while the discharge valve (21) opens. The suction valve and discharge valve Qυ are attached to the valve mounting plate (a) inserted between the cylinder head e (l) and the cylinder flock → in the second cylinder (3). By doing so, both valves-■D
is the position closest to the top surface of the piston (c), and the gap volume at the end of compression and the beginning of suction when the piston (c) is at the top dead center of the two-dot chain line is the position closest to the top surface of the suction boat (c).
Of course, the volumes of the passages (C) and (A) connected thereto are not added to the volumes of the 2nd cylinder (3) and the discharge bow +- (14), and are significantly smaller. )
It is possible to increase the compression ratio and volumetric efficiency of the suction valve (e) and the discharge valve (e2f) and f) by attaching it to the valve mounting plate (a). It outlet valve &1) is attached to the valve mounting plate (A) in advance, and by installing or removing this valve mounting plate (A) between the cylinder head cover and the cylinder block (to), It can be assembled and disassembled.

In the previous example, the central second air in the three-cylinder engine was
It may have been the case that (3) was used as a supercharging cylinder, or @1 cylinder (
2) Or the third cylinder (4) may be used as a supercharging cylinder and the other cylinders may be used as combustion cylinders, and it is also applicable to multi-cylinder engines such as 4-cylinder or 6-cylinder engines. Not even. In addition, the structure of the suction valve and discharge valve I2) may be a reed valve type as shown in Figure 2, or a type in which a flat valve body is supported by a spring as shown in Figure 3. , it goes without saying that it can also be used as a dialect.

As described above, the present invention allows some of the plurality of cylinders to
In a multi-cylinder internal combustion engine configured as a supercharging cylinder for other combustion cylinders, a valve mounting plate is inserted between the cylinder head and the cylinder block in the supercharging cylinder, and the valve mounting plate is inserted between the cylinder head and the cylinder block. A check valve type suction valve and a counter pressure valve type discharge valve are attached to the supercharging cylinder, which reduces the gap volume in the supercharging cylinder and increases its compression ratio and volumetric efficiency. As a result, the suction efficiency and supercharging efficiency to the engine are significantly improved, and the engine output and fuel efficiency can be improved.Moreover, the assembly and disassembly of the suction valve and discharge valve in the supercharging cylinder is easy. Since the valve mounting plate can be inserted and removed between the cylinder head and cylinder flock at the same time, it has the effect of significantly reducing the labor required for assembling and disassembling both valves. .

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, FIG. 1 is a schematic plan view of an engine equipped with the valve device of the present invention, and FIG.
-W enlarged cross-sectional view, FIGS. 3 and 4 are 1] showing other types of suction valves and discharge valves. (])...Engine, (2) (3) (4)...Cylinder, 0...Air cleaner, 09)...Intake passage, 0
8) Carburetor, (c) Cylinder head, Cylinder block, (A) Valve mounting plate, Suction valve, c/21)... discharge valve. 9-

Claims (1)

[Claims] (1) Some cylinders out of a plurality of cylinders are used for supercharging with respect to other combustion cylinders (in a multi-cylinder internal combustion engine configured in this way, the gap between the cylinder head and the cylinder block in the supercharging cylinder is Insert the valve mounting plate into the valve mounting plate, and insert the valve mounting plate into the valve mounting plate.
A valve device for a supercharging cylinder in a supercharging multi-cylinder internal combustion engine, characterized in that a check valve type suction valve and a check valve type discharge valve are installed in the supercharging cylinder.