JPH03217609A - Intake/exhaust system of engine using tappet valve together with rotary valve - Google Patents

Abstract

PURPOSE:To reduce the number of tappet valves and simplify a valve device by overlapping a cylindrical rotary valve on a tappet valve to use as a valve. CONSTITUTION:A cylindrical rotary valve 1 is overlapped on a tappet valve 2. Rotation of the rotary valve is corresponded to four stroke of an engine, and the opening part of a cylindrical part is selectively communicated to an intake port 3 or an exhaust port 4. The opening part of the rotary valve on the combustion chamber side is opened/closed through the tappet valve. Hereby, because intake and exhaust can be performed with one same tappet valve, the number of valves can be reduced and the valve device can be simplified. Further, assembly and adjustment of the valve can be easily performed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an intake/exhaust device for an engine.

(Prior art) In conventional engines, the tappet valve provided in the cylinder bore of the engine head is provided exclusively for intake and exhaust. There is a shift to multiple valves, such as 2 valves or 3 to 4 valves.

(Problem to be solved by the invention) At present, increasing the number of valves in an engine is a means of increasing engine speed (increasing output), and by increasing the number of valves, each valve is made smaller. Therefore, we are struggling to lower the inertial mass and make it compatible with higher speeds.

For this reason. The engine head is much larger than before, and inside, multiple camshafts are used to drive the rocker arms and act on the tappet valves.

Furthermore, the valve also includes a lift spring, etc., and is packed tightly into the limited space.

These parts inside the engine head become difficult to maintain and maintain valve clearance.

From the viewpoint of maintaining airtightness inside the cylinder, it is advantageous to have fewer valves.

The issue is how to increase the rotational speed of the engine, but I think that the most important themes in any era are higher performance, lighter weight, simplicity, and lower cost.

(Means to solve problem C) Therefore, as a means to get as close as possible to the moon drifting, we will take on the challenge of simplifying the engine head and increasing the output.We will review the engine valves and find that each valve has one for intake. I understand that it is divided and driven exclusively for exhaust.

The second thing is that these valve groups located in the same engine head are used only for the 5008, and we decided to use the following method to use all valves at the same time.

Since the valve moves intermittently, the gaps can be used to switch between intake and exhaust.

Conventionally, three or four valves were required for the engine head, but in this engine, the purpose can be achieved by using only two valves at the same time.

First, a cylindrical rotary valve with a cylindrical side surface and an opening at the bottom is superimposed on the dappete valve shown in Fig. 1 and rotated, and an opening is also formed in a part of the engine head that serves as the housing of the rotary valve. Set up and respond.

(Function) By constantly rotating the rotary valve in this way,
The tappet valve opens only during the engine's intake and exhaust strokes, and closes during the compression and combustion strokes to maintain the air in the cylinder.

The rotating rotary valve is part of the engine's intake stroke,
The opening in the housing and the opening in the rotary valve are aligned in time with the exhaust stroke.

The tappet valve uses the same valve for intake and exhaust, and the rotary valve above it distributes the air to the intake hole during the intake stroke and to the exhaust hole during the exhaust stroke.

Usually there are 2 valves or 3 and 4 in the encinhenod.
The intake valve and exhaust valve each operate independently, even in a 4-valve engine.
Two valves are operated at a time to correspond to the intake and exhaust strokes.

In the case of a two-harvest engine, the valve device of the invention operates two valves, which are all the valves, at the same time to perform the intake and exhaust strokes.

(Example) Figure 3 shows the basic model of this device. To explain it, first, one tappet valve and one rotary valve are operated by overlapping the mouth = tally valve from the top of the tappet valve. There is.

The tappet valve and rotary valve are rotatably engaged, so the tappet valve moves up and down, and the rotary valve rotates on the spot to correspond to the intake and exhaust holes.

Figure 4 shows the process during one stroke of a 4-stroke engine.
From the stroke to the intake stroke, the second compression stroke, and then the ignition.
explosion. The engine progresses to the third stroke, the combustion stroke, and the fourth stroke, the exhaust stroke, and then ends.

Therefore, in this device, the rotation of the rotary valve is made to coincide with these four strokes.

This corresponds to 1/2 of the rotation of the engine crankshaft, and when applied to the casing that houses the rotary valve of this device, Figure 5 shows the inner wall of the casing between the exhaust stroke of the 4th stroke and the intake stroke of the 1st stroke. Openings for intake and exhaust are provided in the valve, and these openings match the openings of the rotary valve.

Additionally, the exhaust valve is left open during the above-mentioned stroke, and a rotary valve is used to advance from exhaust to intake.

In the device shown in Figure 6. A rotary valve acts on two tappet valves, with an intake pipe at the bottom of the diagram, an exhaust pipe at the top, and valves that are a combination of tappet and rotary valves lined up between the two, and the housing of the rotary valve. A partition wall is provided between the valves lined up in the section.

The two rotary valves rotate in a symmetrical direction from the inside to the outside toward the intake pipe with their openings together, and the tappet valve is in the ozone state during the intake stroke, which is the first stroke of the engine. Then, when the piston reaches the bottom dead center, the tappet valve is closed and the second stroke, the compression stroke, begins.

Immediately before the piston reaches top dead center, the ignition cylinder explodes and burns at the ignition plug, pushing the piston down and proceeding to the third combustion stroke.After the piston reaches bottom dead center, the tappet valve begins to open. Proceed to the fourth stroke, the exhaust stroke.

There, the opening of the rotary valve aligns with the exhaust pipe and exhaust begins, and the exhaust stroke continues until the piston reaches top dead center, whereupon the engine advances to the first stroke and the engine continues its stroke.

The partition walls between the rotary valves are used to prevent blow-through from the intake side to the exhaust side and to maintain airtightness of the device.

(Effect of the invention) a. The valve device is simplified.

b. Even with a small number of valves, it is possible to have the same effect as a multi-valve device.

C. It can respond to higher speeds of engines.

d. Because there are fewer valves, assembly and adjustment are easier.

e. Intake and exhaust are performed using the same valve, which prevents the valve from overheating.

[Brief explanation of drawings]

FIG. 1 shows a perspective view of a tappet valve. Figure 2 shows a perspective view and a side sectional view of the rotary valve. It is used by superimposing it on the tapest valve shown in Fig. 1. FIG. 3 shows a side sectional view of the basic form of the entire valve device. FIG. 4 diagrammatically shows one stroke of the engine. FIG. 5 shows a front view of the rotary valve housing including the rotary valve, intake pipe, and exhaust pipe. FIG. 6 shows a valve device using two rotary valves.

Claims (4)

[Claims] (1) Overlap the cylindrical rotary valve shown in FIG. 2 on top of the tappet valve shown in FIG. 1. (2) Openings are provided in the bottom and side surfaces of the cylindrical rotary valve so that the valve can rotate and correspond to the intake and exhaust holes provided in the housing of the rotary valve. (3) A slope is provided inside the cylindrical rotary valve from the opening to reduce flow resistance, as shown in the cross-sectional view of FIG. (4) The two sets of valves shown in FIG. 6 are arranged in the valve system shown in FIG. 3, and the two rotary valves are rotated symmetrically to perform intake and exhaust.