JPH07293214A - Valve device for internal combustion engine - Google Patents

Abstract

PURPOSE:To simplify a valve device and to deal with the performance enhancement of an internal combustion engine characterized in such as a variable valve timing and the like. CONSTITUTION:Inside the base end parts of air intake and exhaust pipes 4 and 5, a hole 6 is provided on air intake and exhaust passages 4a and 5a for connecting the respective pipes 4, 5 to a combustion chamber. A valve 11 having a closed part 13 and a circulation path 14 is rotatably provided in the hole 6 in order to open or close the air intake or the exhaust passage rotatably inside the hole 6. The valve 11 is rotated synchronously with the vertical movement of a piston P. Each pipe is opened when the flow path 14 is above the passage 4a or 5a of the air intake or the exhaust and air is taken in or exhausted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device for an internal combustion engine.

[0002]

2. Description of the Related Art Generally, a prime mover used for automobiles, motorcycles, ships and the like is a 4- or 2-cycle gasoline engine or a diesel engine. Each of these internal combustion engines repeats the strokes of intake, compression, explosion, and exhaust to extract kinetic energy. Among these, the intake and exhaust (exhaust for uniflow type diesel engine) is controlled. As shown in FIG. 17, this is a valve device except for the case of a small two-stroke gasoline engine used for motorcycles and the like. Incidentally, FIG. 17 shows a valve device of a conventional 4-cycle gasoline engine. This valve V is a member generally formed in a mushroom shape, that is, a mushroom valve (poppet valve), and at the top of the combustion chamber N, It is arranged at the opening of the intake and exhaust pipes. The valve mechanism such as the cam C or the tappet Ta reciprocates the mushroom valve in its axial direction to open and close the intake and exhaust pipes.

[0003]

By the way, regarding an automobile, for example, there are remarkable improvements in engine performance and output in recent years, but the improvement of the valve device is at the core of this. In internal combustion engine, high output,
In order to achieve high efficiency, improvements have been made to improve intake efficiency or intake amount, and to achieve high rotation without sacrificing in the low rotation range. Under such circumstances, the number of valves and the number of valve timings are being varied (cams, rocker arms, etc.), but the obstacle here is the problem of the conventional valve device itself.

The problem is as follows for the valve device of the automobile. (1) The limit of substantial opening area and ventilation resistance due to the shape of the valve. (2) Since the valve reciprocates linearly and opens and closes by a cam and a spring, each member may resonate, and there is a limit to the allowable number of rotations. Further, vibration and noise due to the linear reciprocating motion of many members including the valve cannot be avoided. (3) If the number of constituent parts is large and the performance is further improved, the number of parts and cost are further increased, and the size of the entire apparatus is increased. (4) The valve timing is desired to be changed in order to obtain the best intake efficiency suitable for each rotation speed, but the degree of freedom in design is not necessarily large.

Further, the conventional valve device is not limited to these problems, but has many problems due to its structural complexity. Further, there are great expectations for future development and application, and the development of new valve devices has been awaited. The present invention has been made in view of these problems of the conventional valve device, and an object of the present invention is to provide a valve device that is simple and capable of coping with higher performance.

[0006]

In order to achieve the above object, a valve device according to the present invention has a hole in which a columnar body is rotatable in an intake or exhaust passage leading to a cylinder,
A closing part for closing the passage and a flow passage for opening the passage are provided on the same cross section perpendicular to the rotation axis so that the intake or exhaust passage is opened and closed by rotating in the hole. A valve formed by the above is rotatably provided in the hole. In this case, it is preferable that the valve is provided in each cylinder of an internal combustion engine having a plurality of cylinders, and the valves are integrally connected with their rotation axes aligned.

And, in these, the valve is
Both the intake passage connecting the inside of the cylinder and the intake pipe and the exhaust passage connecting the inside of the cylinder and the exhaust pipe may be opened and closed in common. Further, the flow passage may be a concave groove having a split circular shape in a cross section perpendicular to the rotation axis of the valve, or a through hole formed so as to intersect with the rotation axis of the valve. You can also In any case, the valve may be attached to the intermittent driving means and rotated intermittently.

[0008]

In the valve device constructed as described above, when the valve rotates in the hole and the intake or exhaust passage is closed by the closing portion, the passage is closed, and the intake or exhaust passage and the flow passage. When the two communicate with each other, the passage is opened. in this case,
When the valves of the plurality of cylinders are integrally connected, one valve opens and closes the intake or exhaust passage of each of the plurality of cylinders.

When the valves are common to the intake and exhaust passages, one valve opens and closes both passages. Further, when the flow passage is a concave groove having a split circular shape in a cross section perpendicular to the rotation axis of the valve, the intake or exhaust passage is opened every one rotation of the valve, and the flow passage is rotated by the valve. If the through hole intersects the axis, the intake or exhaust passage is opened every half turn of the valve. Then, when the valve is intermittently rotated, the intake or exhaust passage is quickly opened and closed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the valve device of the present invention will be described in detail with reference to FIGS. The valve device of this example is embodied in a 4-cycle gasoline engine (in-line 4-cylinder) for an automobile. The cylinder block 1 is composed of a cylinder portion 2 having four cylinders (only one is shown in the figure) and a cylinder head 3. At the top of the cylinder head 3, for each cylinder, a pair of intake pipes 4 and The exhaust pipe 5 is erected in a V-shaped cross section. Both pipes 4 and 5 are the same as those known in the art, and the air-fuel mixture is supplied from the intake pipe 4 into the cylinder, and the combustion gas in the cylinder is discharged from the exhaust pipe 5. At the base end side of the intake passage 4a or the exhaust passage 5a, which is a fluid passage connecting the combustion chambers with the respective pipes inside the intake pipe 4 and the exhaust pipe 5 at the head of the cylinder, In the cylinder arrangement direction,
A hole (cylindrical insertion portion) 6 in which a cylindrical body having a predetermined diameter is rotatable is provided in a penetrating manner in the lateral direction.

As shown in FIG. 5, the valve 11 in this example is a cylindrical shaft (rod) having an outer diameter slightly smaller than the inner diameter of the hole 6, and one end thereof is made of metal. The sprocket (gear) 12 is attached. However, the valve 11 in this example is formed of metal, ceramic, or the like. The outer peripheral surface (arc portion) of the valve 11 forms a closing portion 13 that closes the intake passage 4a or the exhaust passage 5a, as will be described later, but the four flow passages 14 in the axial direction correspond to each cylinder. 14 are provided by shifting the bottom surface (notch bottom surface) 15 of each flow passage by 90 degrees.
It has a closing portion 13 for closing a and 5a and a flow passage 14 for opening the passage on the same cross section perpendicular to the rotation axis. Thus, in this example, the four valves are integrally connected with their rotation axes aligned. In addition,
The flow passage 14 is a concave groove having a predetermined width W and having a split circle shape (notch shape) in a cross section perpendicular to the rotation axis of the valve 11. The valve 11 of this example is rotatably inserted in the hole 6, and each flow passage 14, 14 is inserted in the inserted state.
14 are provided so as to correspond to the positions of the four cylinders and the positions of the intake pipe 4 and the exhaust pipe 5, respectively. In this way, the valve 11 of the present example is provided in the cylinder and in the intake pipe 4.
A common valve that opens and closes both an intake passage 4a that connects the two and an exhaust passage 5a that connects the inside of the cylinder and the exhaust pipe 5 to each other. The valve 11 has a cylindrical shaft,
It is assembled by being axially inserted into a hole 6 which is a mounting portion of a valve on the cylinder side.

As shown in FIG. 6, the angle A formed by the leading edge 14a and the trailing edge 14b of the flow passage 14 is less than 180 degrees (a little over 135 degrees in this example), and the opening point 4k and the closing side on the intake side are closed. The angle B formed by the point 4h is slightly less than 45 degrees. Further, as shown in FIG. 7, the angle C formed by the open point 5k and the close point 5h on the exhaust side
In addition, the angle D formed by the closing point 4h on the intake side and the opening point 5k on the exhaust side is each less than 45 degrees. Thus, in this example,
When the valve 11 rotates in the hole 6, the intake or exhaust passages 4a and 5a are opened and closed.
The axial width W of the flow passage 14 is smaller than the inner diameter Ds of the cylinder and slightly larger than the inner diameter 4d of the intake pipe 4 (and the exhaust pipe 5) as shown in FIG. Further, while the above-mentioned members are exposed to heat during use, the valves and the cylinders are formed of a material having the same thermal expansion coefficient or the latter being a slightly larger material. Although not shown, necessary sealing is applied to both the valve and the cylinder head.

A timing belt (not shown) is wound around the sprocket 12 and a crankshaft sprocket (not shown), and the valve 11 is rotated by the rotation of the crankshaft. Incidentally, T is an ignition plug, and the piston P and the like have the same construction as the conventional one.

Next, the operation of the valve device of this embodiment constructed as described above will be described. However, it is assumed that the valve 11 continuously rotates clockwise. First, opening and closing of the intake pipe 4 will be described (see FIG. 6). When the valve 11 rotates and the front edge 14a of the flow passage 14 passes through the open point 4k on the suction side (solid line in FIG. 6), the suction pipe 4 and the flow passage 14 of the valve 11 communicate with each other to open the intake pipe 4. When the valve 11 further rotates to the position shown by the alternate long and two short dashes line in FIG. 6 and the trailing edge 14b of the flow passage 14 reaches the closing point 4h, the suction pipe 4 is closed, but the suction pipe 4 is open. The rotation angle of 11 is set to a little over 90 degrees in this example. After that, the valve 11 rotates, and the leading edge 14a of the flow passage 14 is again generated.
The suction pipe 4 is closed until the open point 4k is reached.

Next, the exhaust pipe 5 will be described (see FIG. 7).
When the valve 11 is rotated about 180 degrees from the state where the intake pipe 4 is closed (indicated by the chain double-dashed line in FIG. 6), the front edge 14a of the flow passage 14 passes through the open point 5k on the exhaust side ( (Solid line in FIG. 7), the exhaust pipe 5 and the flow passage 14 of the valve 11 communicate with each other to open the exhaust pipe 5. Further, the valve 11 rotates,
When the trailing edge 14b of the flow passage 14 reaches the closing point 5h, the exhaust pipe 5
Is closed (two-dot chain line in FIG. 7), but the angle at which the valve 11 rotates with the exhaust pipe 5 open is a little over 90 degrees.
After that, the valve 11 is rotated and the leading edge 1 of the flow passage 14 is again generated.
The exhaust pipe 5 is closed until 4a reaches the open point 5k.
In this example, as described above, the intake pipe 4 and the exhaust pipe 5 are opened and closed by the single valve 11.

Next, each stroke, that is, the relationship between the movement of the piston P and the opening / closing of the intake pipe 4 and the exhaust pipe 5 will be described with reference to FIGS. During the four strokes of compression, explosion, and exhaust, the valve 11 makes one rotation. First, in the suction stroke, as shown in FIG. 1, first, the piston P is substantially at the top dead center. On the other hand, in the valve 11, the front edge 14a of the flow passage 14 is substantially at the open point 4k on the suction side (solid line in FIG. 1). When suction starts, the valve 11 rotates to open the suction pipe 4. On the other hand, the piston P descends while inhaling the mixture of fuel and air as shown by the chain double-dashed line in FIG. Then, as shown by the solid line in FIG. 2, when the piston P almost reaches the bottom dead center, the trailing edge 14b of the valve 11 reaches the closing point 4h on the intake side to close the intake pipe 4 and the intake stroke ends. To do.

Next, in the compression stroke, as shown in FIG.
As shown by the chain double-dashed line, the piston P that is approximately at the bottom dead center rises while compressing the air-fuel mixture, and as shown in FIG.
Almost to top dead center. On the other hand, the valve 11 has a state in which the trailing edge 14b of the flow passage 14 is substantially at the closing point 4h on the suction side (see FIG. 2).
Continues to rotate from the middle and solid lines), but intake pipe 4 and exhaust pipe 5
Are closed together (two-dot chain line in FIG. 3).

The explosion (expansion) stroke is as shown in FIG.
The ignition plug T ignites the air-fuel mixture when the piston P is almost at the top dead center. Then, the piston P is pushed down by the expansion of the combustion gas as shown by the chain double-dashed line in FIG.
As shown in FIG. 4, the bottom dead center is reached. During this time, the intake pipe 4 and the exhaust pipe 5 are closed (in FIG. 3, the solid line and the chain double-dashed line), but the valve 11 continues to rotate, and at the time when the explosion stroke ends, the leading edge 14a of the flow passage 14 is changed. It has almost reached the open point 5k on the exhaust side (see FIG. 4).

In the exhaust stroke, as shown by the chain double-dashed line in FIG. 4, the front edge 14a of the flow passage 14 of the valve 11 is opened beyond the open point 5k on the exhaust side, and the exhaust pipe 5 is opened to cause almost dead bottom. The piston P at the point (solid line in FIG. 4) rises while exhausting combustion gas (two-dot chain line in FIG. 4). And the piston P
When almost reaches the top dead center, the trailing edge 14b of the valve 11 reaches the closing point 5h on the exhaust side to close the exhaust pipe 5 (see FIG. 1),
The exhaust stroke ends. After that, the piston P and the valve 11 continue to operate similarly in the intake stroke again, and the engine continues to rotate.

As described in detail above, this embodiment functions as a valve device for a four-cycle gasoline engine with an extremely simple structure consisting of one valve. Therefore, the number of parts can be reduced and the engine upper part can be downsized.

The present invention is not limited to the above-mentioned embodiment, and various other implementations are possible without departing from the spirit of the invention. For example, the valve 1 in the above
By changing the size (opening cross-sectional area) of the flow passage 14, the intake pipe 4, the exhaust pipe 5, etc., one valve timing different from the above example can be obtained. Specifically, the angle A formed by the leading edge 14a and the trailing edge 14b of the flow passage 14 is increased, or the angle B formed by the intake side open point 4k and the closed point 4h and the exhaust side open point 5k. By reducing the angle C formed by the closing point 5h and the closing point 4h on the intake side and the opening point 5k on the exhaust side, the suction pipe 4
It is possible to increase the overlap in which both the exhaust pipe 5 and the exhaust pipe 5 open.

Further, as shown in FIG. 9, movable pieces Ka and Kb are provided at the open point 4k and the close point 4h on the intake side, and the movable pieces Ka and Kb are provided along the inner peripheral surface of the hole 6 by a swinging means (not shown). When it is rocked, the valve timing can be changed linearly. Of course, the movable piece may be provided at one or both of the open point and the closed point on one or both of the intake side and the exhaust side.

As shown in FIG. 10, the spark plug T
May be provided obliquely. It is also possible to attach spark plugs to the lower portions of both the intake pipe and the exhaust pipe. Further, instead of using the ceramic only for the valve, it is possible to use the ceramic for other members by utilizing the simplicity of the configuration. In particular, if the inner peripheral surface of the hole for mounting the valve is made of ceramic, heat resistance and wear resistance can be further improved. Although the valve is rotated continuously in the above example, it may be rotated intermittently.

In FIGS. 11 to 15, the flow passage 24 is a through hole formed so as to intersect the rotation axis (line) of the valve 21, and the valve 21 is provided for each cylinder on the intake side and the exhaust side. In this embodiment, each cylinder is used independently (however, only one cylinder is shown in the figure). More specifically, a step motor M as an intermittent drive means that can be arbitrarily rotated and stopped is attached to one end of the valve 21 of this example, and a position display means 25 is provided at the other end. A cylinder head (not shown) is provided with a position detection device corresponding to the position display means 25, and the position detection device is further connected to a central control device (hereinafter, CPU). Also, CPU
Signals such as the engine speed and the load are input to, and the step motor M is further connected to the CPU.

The CPU calculates the optimum valve timing according to the signal from the position detecting device, the engine speed and the load, and outputs the signal to the step motor M. Then, the step motor M repeats rotation and stop according to the signal, and drives the valve 21 at a timing according to the speed and the like.

Next, the relationship between each stroke and the opening / closing of the intake pipe 34 and the exhaust pipe 35 of this example will be described with reference to FIGS. 12 to 15. In addition, the following example is a case where the overlap or the like is not large. In the suction stroke, as shown in FIG. 12, initially, the piston P is almost at the top dead center. On the other hand, both the intake pipe 34 and the exhaust pipe 35 are closed (solid line in FIG. 12). When inhalation starts, the inhalation-side valve 21a rotates 90 degrees (clockwise) to the position indicated by the chain double-dashed line in the figure, and stops, thereby opening the inhalation pipe 34 through the flow passage 24a. On the other hand, the piston P is
As indicated by the chain double-dashed line, it descends while inhaling a mixture of fuel and air. When the piston P almost reaches the bottom dead center, the valve 21a rotates 90 degrees again (clockwise).
Then, the suction pipe 34 is closed (solid line in FIG. 13). During this time, the exhaust valve 21b is stopped with the exhaust pipe 35 closed.

In the compression stroke and the explosion (expansion) stroke, both valves 21a, 21a,
21b is stopped with the respective tubes 34 and 35 closed. In the exhaust stroke, as shown in FIG. 15, the valve 21b on the exhaust side rotates 90 degrees (clockwise) and stops as shown by the chain double-dashed line, while the exhaust pipe 35 is opened through the flow passage 24b. The piston P rises while exhausting combustion gas (two-dot chain line in FIG. 15). Then, when the piston P almost reaches the top dead center, the valve 21b rotates 90 degrees again (clockwise) and stops, and the exhaust pipe 35 is closed (FIG. 12).
solid line). During this time, the intake valve 21a is stopped with the intake pipe 34 closed.

As described above, in this example, each valve 21a,
Since every 21b is arbitrarily rotated and stopped, the valve can be opened and closed quickly and the effective ventilation time can be extended. Further, since the valve can be opened / closed at the optimum valve timing according to the engine speed, the load, etc., high output and fuel saving can be achieved. Also, at the time of explosive combustion, both valves 21a, 21
Since both b are stopped, airtightness can be secured. Further, the number of rotations of the valves 21a and 21b may be one fourth of the number of rotations of the crankshaft, that is, the piston P makes two reciprocations in four cycles, that is, the valves 21a and 21b make half rotations while the crankshaft makes two rotations. Therefore, it is possible to cope with high rotation.

FIG. 16 shows, similarly to the first embodiment, a valve 11 having a flow passage 14 formed of a groove having a predetermined width and having a split circle shape (notch shape), an intake pipe 34 side and an exhaust gas side. Tube 3
It is an example in which it was used independently on each of the five sides. In this example, both valves 11 and 11 are continuously rotated counterclockwise (the valve makes one rotation while the piston P makes two reciprocations), and the respective pipes 34 and 35 are opened and closed. Note that FIG. 16 shows the suction stroke.

Although the four-cycle gasoline engine has been described in the above example, it may be embodied as a valve device of a diesel engine (four-cycle, uniflow type, etc.). Further, a two-stroke gasoline engine generally does not have a valve device, but if it is embodied in the valve device, there is a possibility that the performance can be improved without impairing the characteristic of being small and lightweight.

Further, it can be embodied not only as an engine for automobiles but also as a valve device for an engine for other purposes (motorcycle, agricultural machine, small boat, small generator, lawn mower, etc.). The two-cycle engine is inferior to the four-cycle engine in fuel consumption but is small in size, and is generally used as a small power engine. According to the present invention, a conventionally large-sized 4-cycle engine can be downsized, so that it is also possible to provide a small 4-cycle engine with good fuel consumption in a field where a conventional 2-cycle engine has been selected.

[0032]

As described above, according to the present invention, it is possible to reduce the number of parts of the valve device as a whole, and thus it is possible to reduce the cost and the size thereof. Further, since the valve does not make a linear reciprocating motion but only makes a rotary motion, there is no problem such as resonance and it is possible to cope with high-speed rotation. In addition, it is expected that vibration and noise will be suppressed due to the decrease in the number of moving members. Further, when the intake or exhaust passage is fully opened, there is no obstacle like the shaft of the mushroom valve, so that the flow of intake and exhaust can be made smooth or efficient, and the effective area of the opening can be increased. .

When the valves are integrally connected for a multi-cylinder cylinder, the intake or exhaust passages of the plurality of cylinders can be opened and closed by one valve, so that the number of parts can be further reduced. In the conventional valve device, it was necessary to divide the cylinder block and the cylinder head in order to mount the mushroom valve, but according to the present invention, it is possible to integrally form both.

When the valves are common to the fluid passages on the intake side and the exhaust side, both passages can be opened and closed by one valve, and in this case, the number of parts can be further reduced. . Further, if the flow passage is a concave groove having a split circular shape in a cross section perpendicular to the rotation axis of the valve, the shape or structure can be simplified. If the flow passage is a through hole that intersects with the rotation axis of the valve, the intake or exhaust passage can be opened every half rotation of the valve, so that high rotation can be achieved. Further, in the case where the valve is intermittently rotated, the effective ventilation time can be lengthened by quickly opening and closing the intake or exhaust passage, and therefore the intake efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a front sectional view for explanation showing a state in which intake is started in an embodiment in which a valve device of the present invention is embodied in a 4-cycle gasoline engine.

FIG. 2 is a front cross-sectional view showing a state in which compression has also started.

FIG. 3 is a front sectional view showing the same exploded state.

FIG. 4 is a front cross-sectional view showing a state in which exhaust has also started.

FIG. 5 is a perspective view showing a valve used in the embodiment.

FIG. 6 is a partially enlarged front sectional view showing opening and closing of the intake pipe of the embodiment.

FIG. 7 is a partially enlarged front sectional view showing opening / closing of an exhaust pipe of the embodiment.

FIG. 8 is a conceptual plan view showing the relationship among the cylinders, the flow passages of the valves, the inner diameters of the intake pipes and the exhaust pipes of the embodiment.

FIG. 9 is a partially enlarged front cross-sectional view illustrating a means for changing valve timing.

FIG. 10 is a partially enlarged front cross-sectional view in which an ignition plug is attached at a position different from that of the above embodiment.

FIG. 11 is a perspective view and an explanatory view showing a valve and the like of another embodiment.

FIG. 12 is a front cross-sectional view showing a state in which intake is started in an engine equipped with the valve of FIG.

FIG. 13 is a front cross-sectional view showing a state where compression is started similarly.

FIG. 14 is a front cross-sectional view showing the same exploded state.

FIG. 15 is a front cross-sectional view showing a state in which exhaust has started.

FIG. 16 is a front cross-sectional view showing a state where the engine has started inhalation, for explaining still another embodiment.

FIG. 17 is a front sectional view illustrating a valve device of a conventional 4-cycle gasoline engine.

[Explanation of symbols]

 1 Cylinder 4 Intake Pipe 4a Intake Passage 5 Exhaust Pipe 5a Exhaust Passage 6 Hole 13 Closure 14 and 24 Flow Passage 11 Valve

Claims (6)

[Claims] 1. A hole in which a cylindrical body is rotatable is formed in an intake or exhaust passage leading to the inside of a cylinder, and the passage is formed so as to open and close the intake or exhaust passage by rotating in the hole. An internal combustion engine, characterized in that a valve having a closing portion for closing and a flow passage for opening the passage on the same cross section perpendicular to a rotation axis is rotatably provided in the hole. Valve device. 2. The valve is provided in each cylinder of an internal combustion engine having a plurality of cylinders, and the valves are integrally connected with their rotation axes aligned. Internal combustion engine valve device. 3. The valve is common to open and close both an intake passage connecting the inside of the cylinder and the intake pipe and an exhaust passage connecting the inside of the cylinder and the exhaust pipe. The valve device for an internal combustion engine according to item 1 or 2. 4. The valve device for an internal combustion engine according to claim 1, wherein the flow passage is a concave groove having a split circular shape in a cross section perpendicular to the rotation axis of the valve. 5. The flow passage is a through hole formed so as to intersect the rotation axis of the valve.
Alternatively, the valve device for an internal combustion engine according to item 3. 6. The valve according to claim 1, wherein the valve is attached to an intermittent drive means to rotate intermittently.
5. A valve device for an internal combustion engine according to any one of 1.