JPH0968014A - Rotary valve device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise and vibration, save time for the readjustment of a valve clearance and the like, and ensure the operation of a valve even in a high speed area. SOLUTION: A cylinder head 4 is provided with a rotary valve 9 having rotatory-sliding faces 10, 11 formed into conical faces or curved faces and disposed in a mutually facing state. The respective rotatory-sliding faces 10, 11 are so formed as to have an intersecting part toward the inside of a shaft. An intake side sealing means S for passing intake air, and an exhaust side sealing means S' for passing exhaust air are provided on the combustion chamber 3 side. Intake air is led into a cylinder 1 when an in-valve intake passage 12 is communicated with the intake side sealing means S with the rotation of the rotary valve 9 synchronous with a main shaft of an engine, and exhaust air in the cylinder 1 is exhausted when an in-valve exhaust passage 13 is communicated with the exhaust side sealing means S' With this constitution, the progress of intake, compression, combustion and exhaust strokes are made.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary valve device for an internal combustion engine that performs intake and exhaust actions, and relates to a rotary valve device in which reciprocating motion parts are eliminated and each motion is purely rotary motion.

[0002]

2. Description of the Related Art In general, a poppet valve is used as a valve device for an internal combustion engine that performs an exhaust action on intake air, and the valve is opened by a cam and closed by a spring force. Therefore, the reciprocal inertial force of the valve or the like cannot exceed the repulsive force of the spring. Further, in order to avoid malfunction due to thermal expansion of the valve in contact with the high temperature combustion gas, a slight valve clearance is provided between the valve and the portion that drives the valve (rocker arm, tappet, etc.). Conventionally, due to such a structure, problems such as jumping and balance of the valve are likely to occur in the high-speed rotation range, noise and vibration are large, and if the valve seat wears, readjustment of the valve clearance is necessary. there were.

[0003]

DISCLOSURE OF THE INVENTION The object of the present invention is to reduce noise and vibration by eliminating the cams, rocker arms, springs and the like which constitute the conventional valve device and removing the reciprocating motion parts such as poppet valves. It is an object of the present invention to provide a rotary valve device in which the operation of the valve can be surely performed even in a high-speed rotation range, without the need for re-adjustment of clearance.

[0004]

SUMMARY OF THE INVENTION In order to solve the conventional drawbacks, the present invention provides a cylinder head with a rotary valve having a conical surface-shaped or curved surface-shaped rotary sliding surface arranged to face each other, and Each rotary sliding surface fixed firmly and rigidly to the shaft is formed so as to have an intersecting portion toward the inside of the shaft, and further has an intake side sealing means for passing intake air and an exhaust side sealing means for passing exhaust air. Provided on the combustion chamber side, one of the rotary sliding surfaces is brought into close contact with the intake-side sealing means, and the other rotary sliding surface is brought into close contact with the exhaust-side sealing means to perform a sealing action, thereby synchronizing with the main shaft of the engine. By introducing the intake air into the cylinder by communicating the intake passage inside the valve formed in the rotary valve with the intake side sealing means in accordance with the rotation of the rotary valve, and by connecting the exhaust passage inside the valve to the exhaust side sealing means. A structure for discharging exhaust in Linder, thus it was the manner perform each stroke of the intake, compression, combustion and exhaust.

[0005]

The rotary valve provided in the cylinder head has conical surface-shaped or curved surface-shaped rotary sliding surfaces that are arranged so as to face each other, and one of the rotary sliding surfaces is provided with intake-side sealing means. Exhaust side sealing means is closely attached to the other rotary sliding surface to seal the pressure in the combustion chamber.
The intake action is performed by connecting the intake-side sealing means to the in-valve intake passage formed in the rotary valve, and the exhaust action is performed by connecting the exhaust-side sealing means to the in-valve exhaust passage formed in the rotary valve. Be done. The rotary valve is driven in synchronism with the main shaft of the engine, the whole makes pure rotational movement, and the reciprocating parts do not hit each other, so noise and vibration are small, and the valve operation is reliable even in the high speed range. is there.

[0006]

1 (a) shows an embodiment of a rotary valve device for an internal combustion engine according to the present invention, in which rotary valves 9 provided in a cylinder head 4 are arranged so as to face each other and have rotary sliding surfaces 10, 11. Has a conical surface shape in the figure,
Each rotary sliding surface 1 firmly and rigidly fixed to the shaft
0 and 11 are formed so as to have an intersecting portion toward the inside of the shaft. In this case, if the rotary sliding surfaces 10 and 11 are formed so as to have an intersecting portion toward the outside of the shaft as shown in FIG. 6, the shape of the combustion chamber is unfavorable and combustion deteriorates. Reference numeral 1 is a cylinder, 2 is a piston, and the rotary valve 9 is driven by a main shaft (crank shaft) of the engine through, for example, a chain and a sprocket 5, and rotates in synchronization with the main shaft of the engine.
Reference numerals 6 and 7 denote bearings for supporting the rotary valve 9, which are equipped with oil seals and which are rotated by the oil injected from the nozzle 8 to prevent the rotary valve 9 from rotating.
Is designed to be cooled. It is preferable that a slight gap be provided between the outer wall surface of the rotary valve 9 and the inner wall surface of the cylinder head 4 surrounding the rotary valve 9 so that they are not in contact with each other. The cylinder head 4 is AA ′ because of the mounting of the rotary valve 9.
It is divided by lines. The combustion chamber 3 side is provided with an intake side sealing means S for passing intake air and an exhaust side sealing means S'for passing exhaust gas. The former is brought into close contact with the rotary sliding surface 10 and the latter is brought into close contact with the rotary sliding surface 11. The pressure in the combustion chamber is thereby sealed, and the in-valve intake passage 12 formed in the rotary valve 9 communicates with the intake-side sealing means S to introduce intake air into the cylinder 1 to form the rotary valve 9. The in-valve exhaust passage 13 communicates with the exhaust side sealing means S'to exhaust the exhaust gas in the cylinder 1. The mixed intake of fuel and air from the carburetor is supplied into the valve intake passage 12. The in-valve exhaust passage 13 communicates with an exhaust passage formed in the cylinder head 4 (not shown). Thus, the intake, compression, combustion, and exhaust strokes are performed. Next, the intake-side sealing means S (exhaust-side sealing means S ') is a seal body 14 (14') without a gap, a seal ring 15 (15 '), and a spring for suppressing these on the rotary sliding surface 10 (11). 16 (1
6 ') and the intake side sealing means S,
The spring 16 (16 ') is not necessary because if the exhaust side sealing means S'has a little axial play, it will easily come into close contact with the rotary sliding surfaces 10 and 11 due to the pressure rise in the combustion chamber. As the seal ring 15 (15 '), it is preferable to use a seal type joint having a special shape as shown in FIG. 1 (b) or (c), the outer periphery of which is a machined corresponding wall surface (see FIG. 5 (b) (corresponding to the fitting portion 24). or,
Since the seal body 14 (14 ') needs to closely follow the surface runout of the rotary sliding surface 10 (11) and closely adhere to it, there is a slight gap between the seal body 14 (14') and the corresponding machined wall surface. Has been given. The intake side sealing means S is shown in FIG.
The seal body 14 and the diaphragm seal 20 may be used as shown in (a), and the seal body 14 may be brought into close contact with the rotary sliding surface 10 and sealed by the elastic force of the diaphragm seal 20 itself, as shown in FIG. A seal ring 21 may be fitted on the outer periphery of the seal body 14 and brought into close contact with the rotary sliding surface 10 for sealing. Further, as shown in FIG. 2C, chamfering is applied to the seal body 14 in order to reduce the pressing force against which the seal body 14 is pressed against the rotary sliding surface 10 by the gas pressure while sufficiently securing the strength, that is, the wall thickness. Is considered (because the effective pressure receiving area of the seal body 14 is reduced by an amount corresponding to chamfering).
The above also applies to the exhaust side sealing means S '. The exhaust-side sealing means S'through which high-temperature exhaust gas passes is shown in FIG.
It may be possible to arrange it outside the passage through which the exhaust gas passes to prevent heat damage as shown in (d). It should be noted that the seal body 14 has
The collar 22 may be formed as shown in (e) (the same applies to the seal body 14 '). In the present invention, it is desirable that the outer diameters of the intake-side and exhaust-side sealing means S and S'be equal to each other so that thrust is not generated in the rotary valve 9. As for the materials of the intake side and exhaust side sealing means S, S ', if a material having high thermal conductivity such as Al alloy or copper alloy is used, the temperature of each part is lowered and a high compression ratio can be adopted. Next, returning to FIG. 1 (a), the seal plate 17 (see also FIG. 1 (d)) is pressed by the spring on the rotary sliding surface 10 with which the intake-side sealing means S is in close contact, and its role is the valve. Internal intake passage 1
This is to prevent the liquid fuel flowing in 2 from scattering outside due to the rotation of the rotary valve 9.
It is not necessary to directly contact the corresponding wall surface of the cylinder head 4 (contact with a spring or the like). In this case, there is no problem as long as the seal plate 17 can be fitted in the rotary valve 9 from the axial direction, but if it cannot be fitted, it is desirable to use a split type as shown in FIG. That is, the upper half of the cylinder head 4 above the line AA 'is removed in advance, the intake side and exhaust side sealing means S, S', and the lower half of the seal plate 17 are assembled, and then the rotary valve 9 is installed. It is possible to fit by assembling and then aligning the upper half of the seal plate 17 with the lower half. Reference numeral 18 is a hole into which the seal body 14 is fitted. FIG. 1F shows a structure in which the seal body 14 and the seal plate 17 are integrated. In order to reduce friction in these seal plates 17, it is desirable to coat the surface with a solid lubricant such as Teflon having a small friction coefficient. Lubrication between the intake side sealing means S and the rotary valve 9 of the seal plate 17 is performed by the lubricating oil mixed with the fuel flowing through the in-valve intake passage 12 at a constant ratio or at a variable ratio according to the load. Exhaust side sealing means S '
The lubrication between the rotary valve 9 and the rotary valve 9 may be performed by the centrifugal force of itself by supplying the lubricating oil pumped by a metering pump (not shown) to the groove 19 as shown in FIG. By the way, high-temperature exhaust gas flows in the in-valve exhaust passage 13, and it is necessary to minimize thermal deformation of the rotary valve 9. Therefore, as shown in FIG. It is desirable to have a liner 23 with layers. In the figure, the liner 23 has an adiabatic air layer in itself, and the liner 23 is made to encircle during casting. In the present invention, the rotary valve 9 is the engine main shaft 1/2
Alternatively, FIG. 3B shows the rotary valve 9 which is driven at a deceleration of 1/4 or in the latter case. Here, the rotary sliding surface 10,
In-valve intake passage 12 or in-valve exhaust passage 13 on 11
Considering the case of machining each opening of the, the rotary body (indicated by a chain double-dashed line) including the tool and the shaft supporting the tool is the rotary sliding surface 1.
It is desirable to incline the rotary sliding surfaces 10 and 11 so that they can be machined without touching 1 (the rotary sliding surface 10 in the case of machining the opening of the in-valve inflow passage 13).
This is because the machining is difficult when the rotary sliding surfaces 10 and 11 are nearly perpendicular to the axis. 1 / of the engine spindle
The same applies when the drive speed is reduced to 2. FIG. 4 shows various embodiments of the present invention in a single cylinder engine.
In (a), the rotary sliding surfaces 10 and 11 arranged so as to face each other are curved (for example, spherical), and of course, the rotary sliding surfaces 10 and 11 have an intersecting portion toward the inside of the shaft. Has been formed. FIG. 4B shows the seal body 14 (14 ') when the rotary sliding surfaces 10 and 11 are spherical, but it is possible to reduce the axial width h to increase flexibility and improve adhesion. it can. FIG. 4 (C) shows the in-valve exhaust passage 13 in FIG. 1 (A) connected to the end face of the rotary valve 9 instead of the outer peripheral face. It uses an axial flow system that allows exhaust gas to flow out. In FIG. 4D, the valve intake passage 12 communicates with the outer peripheral surface of the rotary valve 9.

An example of applying the present invention to a four-cylinder engine is shown in FIG.
In (a), the inside of the shaft is divided into two parts in the figure, and intake air is made to flow in from both ends. However, since it is possible to connect a fuel supply device to each, it is possible to distribute fuel more than in the case of making it flow in from one end. Is advantageous. When it is necessary to cool the rotary valve 9, the sleeve 26 is inserted and fixed to the inner surface of the passage in the shaft as shown in FIG. 5C, and a cooling liquid such as water or oil is placed in the cooling space 27 formed on the outer periphery thereof. It is configured to flow. By the way, depending on how much the rotary sliding surfaces 10 and 11 are inclined with respect to the axial center, as shown in FIG. 5B, the intake side of the cylinder head 4 (more specifically, the lower half of the line AA ′), When machining the fitting portion 24 into which the exhaust side sealing means S, S ′ are fitted, the rotating body 25 including the tool and the shaft supporting the tool does not come into contact with any part of the cylinder head 4 and can be machined. It is preferable to incline the rotary sliding surfaces 10 and 11 (usually, the rotor 25 is most likely to come into contact with the portion indicated by the arrow). This is because it is difficult to machine the fitting portion 24 when the rotary sliding surfaces 10 and 11 are nearly perpendicular to the axis. FIG. 5D shows an embodiment of the present invention in which each cylinder is independently provided with a rotary valve having a conical surface-shaped or curved surface-shaped rotary sliding surface arranged so as to face each other. Further, as a method of installing the rotary valve, it may be considered that the axis is parallel to the axis of the cylinder as shown in FIG. Next, in FIG. 5 (f), the intake air supplied from the carburetor or the like is sucked into the crank chamber through the reed valve 28, and is introduced into the cylinder 1 through the reed valve 29 and the rotary valve 9 during the downward stroke of the piston 2. Introduced the piston 2
The rotary valve 9 after compression, ignition, and combustion accompanying the movement of the
Combustion gas is exhausted through the. The intake air is introduced twice into the crank chamber and once into the cylinder 1 while the piston makes two reciprocations, so supercharging is performed by the difference. Conventionally, in such a crank chamber compression type supercharged engine, its action is performed by a poppet valve,
In order to overcome the drawback, the rotary valve 9 according to the present invention is used. The intake side and exhaust side sealing means are omitted (the same applies to FIGS. 5D and 5E).

[0008]

The prior art is a valve device having a reciprocating part such as a poppet valve, which requires a valve clearance to avoid malfunction due to thermal expansion of the poppet valve. In the present invention, since the entire rotary valve device performs pure rotary motion, the valve operation is reliable even in the high speed range, and high speed rotation is possible. Since there is no equivalent to the conventional valve clearance, it is troublesome to readjust it. Is easy to maintain, and noise and
It also has the advantage of reducing vibration. Further, in the rotary valve device according to the present invention, since the rotary sliding surfaces 10 and 11 are appropriately inclined, first, the flow of intake air and exhaust gas in the combustion chamber 3 is smooth, and secondly, as shown in FIG. As described above, it is easy to machine the fitting portion 24 into which the intake side and exhaust side sealing means S and S ′ fit, and thirdly, the radial load acting on the rotary valve 9 is the rotary sliding surfaces 10 and 11. Since it appears as a component force corresponding to the inclination angle of, the friction loss is smaller than that of the conventional rotary valve (cylindrical type).

[Brief description of drawings]

FIG. 1 is a diagram of a rotary valve device and main parts of an internal combustion engine according to the present invention.

FIG. 2 is a diagram of intake side and exhaust side sealing means.

FIG. 3 is a diagram of a rotary valve.

FIG. 4 is a diagram of various embodiments of a rotary valve device for an internal combustion engine according to the present invention.

FIG. 5 is a diagram of various embodiments of a rotary valve device for an internal combustion engine according to the present invention.

FIG. 6 is a diagram for reference in comparison with the present invention.

[Explanation of symbols]

1 is a cylinder, 2 is a piston, 3 is a combustion chamber, 4 is a cylinder head, 5 is a sprocket, 6 and 7 are bearings, 8 is a nozzle, 9 is a rotary valve, 10 and 11 are rotary sliding surfaces, 1
2 is an intake passage in the valve, 13 is an exhaust passage in the valve, and 14 and 14 '.
Is a seal body, 15.15 'is a seal ring, 16.1
6'is a spring, S is an intake side seal means, S'is an exhaust side seal means, 17 is a seal plate, 18 is a hole into which a seal body is fitted, 19 is a groove, 20 is a diaphragm seal, 21 is a seal ring, and 22 is Tsuba, 23 is a liner, 24 is a fitting part,
25 is a rotating body, 26 is a sleeve, 27 is a cooling space, 28
・ 29 is a reed valve.

Claims (3)

[Claims] 1. A cylinder head is provided with a rotary valve having conical surface-shaped or curved surface-shaped rotary sliding surfaces which are arranged to face each other, and each rotary sliding surface is firmly and rigidly fixed to a shaft. In addition, each rotary sliding surface is formed so as to have an intersecting portion toward the inside of the shaft, and further, an intake side sealing means for passing intake air and an exhaust side sealing means for passing exhaust gas are provided on the combustion chamber side, The intake side sealing means is brought into close contact with one of the sliding surfaces and the exhaust side sealing means is brought into close contact with the other rotating sliding surface to seal the pressure in the combustion chamber and synchronize with the main shaft of the engine. The intake air is introduced into the cylinder by communicating with the intake side sealing means of the valve intake passage formed in the rotary valve in accordance with the rotation of the rotating rotary valve, and the valve exhaust passage formed in the rotary valve is A rotary valve device for an internal combustion engine, characterized in that exhaust gas in a cylinder is discharged by communicating with an exhaust side sealing means, and thus each process of intake, compression, combustion and exhaust is performed. 2. When machining the fitting portion of the cylinder head into which the intake-side and exhaust-side sealing means is fitted, a rotating body including a tool and a shaft supporting the tool comes into contact with any portion of the cylinder head. The rotary valve device for an internal combustion engine according to claim 1, wherein the rotary sliding surface is inclined to such an extent that it can be machined without performing the machining. 3. When machining each opening of the in-valve intake passage or the in-valve exhaust passage on the rotary sliding surface, a rotating body including a tool and a shaft supporting the tool comes into contact with the rotary sliding surface. The rotary valve device for an internal combustion engine according to claim 1 or 2, wherein the rotary sliding surface is inclined to such an extent that it can be machined without incident.