JPS6343368Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a valve mechanism for a multi-cylinder internal combustion engine, and in particular, when the engine is in operation or at low or medium load, when stopping the operation of some cylinders, the intake and exhaust valves are activated. This relates to a valve train that can stop the engine.

In general, when an internal combustion engine is at a so-called low load with surplus output, such as when idling or when going downhill, pumping loss in the compression process becomes large and the fuel consumption rate worsens.

Therefore, as an improvement measure for this, in the case of conventional multi-cylinder internal combustion engines, by stopping the operation of some cylinders during low to medium load, it is possible to create a high load operating state and improve the fuel consumption rate. has been measured.

As a means to stop the operation of some cylinders in this multi-cylinder internal combustion engine, in the case of electronically controlled fuel injection engines, a method has been used to temporarily stop fuel injection. It cannot be used in equipped engines, and even in cylinders where fuel injection is stopped, the intake and exhaust valves operate as usual, so air is sucked in and discharged as the piston operates. However, pumping losses still remain unavoidable.

Therefore, in recent years, attempts have been made to stop the operation of some cylinders by forcibly increasing the gap between the rocker arm and the valve. It's about to happen.

However, even with this method of stopping the valve operation by forcibly increasing the gap between the rocker arm and the valve, no valve train mechanism that can operate satisfactorily has been developed at present, so this development is difficult. This has become an urgent task.

In view of this situation, the present applicant has previously filed an application (Utility Application No. 130951/1983) to provide this type of excellent valve mechanism, but subsequent research has revealed that it can operate even more safely and reliably. We have devised a valve train for an internal combustion engine that achieves this goal, and we now offer this.

In other words, regarding the valve mechanism for an internal combustion engine that was previously filed, as shown in FIG.
The valve 8 is opened and closed by contacting and swinging the push rod 7 (cam in the case of OHC). First of all, Rotsukashaft 12
The first bush 3 is fitted with an eccentricity e in the downward direction on the Y--Y line passing through the shaft center with respect to the shaft center of the rocker shaft. A second bush is fitted onto the first bush 3 so as to be eccentric by e on the Y-Y line in the same direction as the eccentric direction of the first bush with respect to the axis of the first bush. To explain the principle with reference to Fig. 2, the first bush 3 and the second bush
By rotating and controlling the bushes 4 at the same angle with respect to the axis of the rocker shaft 2 in mutually opposite directions at the same time (the first bushing is rotated clockwise and the second bushing 4 is rotated counterclockwise), the rocker arm R is vertically rotated. By moving it upward, the rocker arm is separated from the valve 8.

Further, as shown in FIG. 2, the axes of the first bushing 3 and the second bushing 4 are fitted and assembled eccentrically on the same line Y-Y with respect to the axis of the rocker shaft 2. Therefore, when the valve in contact with the rocker arm is in the state of intake/exhaust operation due to rocking of the rocker arm, the F
The rocker arm can maintain its normal position in a stable state even when applied with a load in any direction.

Next, its normal operating state will be explained in order. 1st
In the figure, a transmission member 5 is fitted to the rocker shaft 2, a pin 41 is attached to the second bush 4, and a groove 52 (hole is provided at an arbitrary location of the transmission member 5) to allow the pin to fit. (You may do so.)
The pin 41 is fitted into the transmission member, so that the transmission member and the second bushing are configured to interlock with each other. Connecting pins 31 are placed on the first bushing 3 and the transmission member 5 at the same distance from the axis of the rocker shaft, respectively.
51, and links 6, 6 of equal length are connected to the connecting pins 31, 51, the other ends of the links are connected at the same fulcrum 9, and the same fulcrum 9 is connected to the air cylinder 10. There is. In the case of Figure 1, valve 8 is in contact with rocker arm R.
Although the air intake and exhaust operations are carried out by the rocking of the rocker arm, in order to stop the operation of some cylinders during operation of a multi-cylinder internal combustion engine or at low or medium load, there is a mechanism installed in the air cylinder 10. By moving the piston 11 vertically upward by sending pressurized air through the lower air supply hole 13, the same fulcrum 9 connected to the piston rod 12 also moves, and the first bush 3 is moved through the links 6, 6. Then, the second bushing 4 is simultaneously rotated in opposite directions at the same angle with respect to the axis of the rocker shaft 2 via the transmission member 5 (the first bushing is clockwise, the second bushing is counterclockwise), and the rocker arm R is rotated vertically upward. direction to separate the rocker arm R from the valve 8, so that the rocker arm R is moved toward the push rod 7.
Even if the cylinder oscillates, the valve 8 will not operate, and the operation of some cylinders will be stopped during operation of the multi-cylinder internal combustion engine. Conversely, to restart a partially stopped cylinder,
The air pumped through the lower air supply hole 13 of the air cylinder 10 is released, and the compressed air is sent through the upper air supply hole 14 to move the piston 11 vertically downward, thereby causing the rocker arm R and the valve 8 to move.
are brought into contact, and intake and exhaust operations are performed by normal swinging of the rocker arm.

As described above, the rocker arm R and the valve 8 are finally separated or connected due to the vertical movement of the piston 11 due to air being forcedly fed from the lower air supply hole 13 or the upper air supply hole 14 of the air cylinder 10. be. However, if the compressed air is no longer supplied due to a failure in the air supply device of the air cylinder 10 while the engine is running,
The piston 11 of the air cylinder 10 cannot be stopped at a certain position, and the piston 11 is in a halfway state, resulting in incomplete combustion in the engine, and there is a risk of valve breakage, which may lead to an accident while the vehicle is running.

This invention further improves the internal combustion engine valve mechanism that was previously applied for, and makes it possible to perform intake and exhaust operations with the rocker arm and valve in contact even if the air cylinder supply source fails. The present invention proposes a valve mechanism for an internal combustion engine that can operate reliably.

That is, the first bushing is fitted onto the rocker shaft eccentrically downwardly on the Y-Y line passing through the shaft center with respect to the shaft center of the rocker shaft;
on the bushing with respect to the axis of the first bushing.
A second bushing is fitted eccentrically on the Y-Y line in the same direction as the eccentric direction of the bushing, and a rocker arm is loosely inserted onto the second bushing, and the first bushing and the second bushing are connected to the axis of the rocker shaft. In a valve operating mechanism for an internal combustion engine configured to separate a rocker arm from a valve by rotating and controlling the rocker arm in opposite directions simultaneously at the same angle relative to the center, the locker arm is interlocked with the first bushing and the second bushing, respectively. Two links are provided, the other ends of each link are connected at the same fulcrum, the same fulcrum is connected to the piston rod of the air cylinder, and a support member is provided on the piston rod near the same fulcrum of each link, and the support member is provided on the piston rod near the same fulcrum of each link. The air cylinder is characterized in that an elastic body is disposed between the member and the lower outer wall of the air cylinder, and a space is formed by sealing compressed fluid in the elastic body.

Embodiments of the present invention will be described in detail below with reference to the drawings.

As shown in FIG. 3, in the air cylinder 10, a support member 17 is provided on the piston rod 12 near the same fulcrum 9 of the two links 6, 6, and an elastic member 17 is provided between the support member and the lower outer wall of the air cylinder. A body 5 is provided, and a space 16 is formed by sealing a compressed fluid in the elastic body (the supply source is not shown). When a multi-cylinder internal combustion engine is in operation, at low or medium loads, to stop the operation of some cylinders, the piston 11 is raised by pumping air through the lower air supply hole 13 of the air cylinder 10, The same fulcrum 9 is moved vertically upward, and then the rocker arm R is moved vertically upward according to the principle explained in FIGS. Therefore, the valve 8 will not operate even if it swings. Conversely, when returning to normal operating conditions, the air forced through the lower air supply hole 13 is released, and pressurized air is fed into the air cylinder through the upper air supply hole 14 to move the piston 11 vertically downward. As a result, the rocker arm R and the valve 8 come into contact with each other, and normal rocking of the rocker arm R allows intake and exhaust operations to be performed. However, if the air cylinder 10, which is the air supply source, becomes inoperable due to some kind of failure, compressed fluid is automatically sealed into the notch in the elastic body from another supply source (not shown). This causes the elastic body to swell in the radial direction and thus to stretch in the axial direction.
Therefore, regardless of the position of the piston, its elastic force will surely return the piston to its lowest point, and the air cylinder will remain in contact with the rocker arm R and the valve 8 until the air cylinder malfunction is corrected, so that intake and exhaust operations can be performed. When the air cylinder is operated under the above conditions and operates normally, the compressed fluid sealed within the elastic body 15 is configured to flow out.

As shown in FIG. 4, the elastic body 15 provided between the support member 16 and the lower outside of the air cylinder is shaped like a bellows so that the elastic body 15 operates smoothly with respect to the vertical movement of the piston 10.

Furthermore, in FIGS. 3 and 4, the air cylinder 10 was provided with a lower air supply hole 13 and an upper air supply hole 14, but as shown in FIG.
0 is provided with only a lower air supply hole 13, and when the piston 11 is located at the highest point in the air cylinder, compressed air is retained between the piston 11 and the upper inner wall of the air cylinder. The piston 11 is formed into a convex shape so that a space 17 is partially formed. In this case, the piston 11
When the piston 11 is to be raised, pressurized air is sent through the lower air supply hole 13, and conversely, when the piston 11 is to be lowered, the pressurized air that has been forced through the lower air supply hole 13 is released, and the elastic force of the elastic body 15 is The piston 11 can be lowered by the compressed air force forced into the space, but if the elastic force of the elastic body 15 is weak, the piston 11 can be lowered by enclosing compressed fluid in the elastic body. is also possible.

Since the present invention has the configuration as explained above, even if the air supply device stops functioning due to some kind of accident, compressed fluid can be automatically filled into the elastic body from another supply source. This causes the elastic body to expand in the axial direction and the piston to return to its lowest point. Therefore, the locking arm and the valve are in contact with each other so that intake and exhaust operations can be performed.
Particularly, when the operation of some cylinders is stopped during low or medium load while the engine is operating, the system can operate smoothly and safely. Furthermore, the valve operating mechanism maintains a stable holding state of the rocker arm even during normal valve operation, and has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a partial cross-sectional front view showing the valve train mechanism applied for earlier, Fig. 2 is a partial cross-sectional schematic diagram showing the valve train mechanism applied for earlier, and Figures 3 to 5 are examples of the present invention. FIG. 2 shows a partially sectional front view showing a certain valve mechanism. Explanation of the numbers, R...Rotsuka arm, 2...Rotsuka shaft, 3...First bushing, 4...Second bushing, 5...Transmission member, 6...Link, 7...
Push rod, 8... Valve, 9... Same fulcrum, 10... Air cylinder, 11... Piston,
12...Piston rod, 13...Lower air supply hole, 14...Upper air supply hole, 15...Elastic body,
16... cut portion, 17... support member.

Claims (1)

[Claims for Utility Model Registration] (1) A first bushing is fitted onto the locking shaft eccentrically downward on the Y-Y line passing through the axis with respect to the axis of the locking shaft; A second bushing is fitted eccentrically on the Y-Y line in the same direction as the eccentric direction of the first bushing with respect to the axis of the first bushing, and a rocker arm is loosely inserted onto the second bushing. In a valve operating mechanism for an internal combustion engine, the first bushing and the second bushing are simultaneously rotated and controlled in opposite directions at the same angle with respect to the axis of the rocker shaft, thereby causing the rocker arm to separate from the valve. , two links respectively interlocking with the first bushing and the second bushing are provided, the other ends of each link are connected at the same fulcrum, the same fulcrum is connected to the piston rod of the air cylinder, and the same fulcrum of each link is connected. A support member is provided on the piston rod near the fulcrum, an elastic body is placed between the support member and the lower outer wall of the air cylinder, and a space is formed by sealing compressed fluid within the elastic body. A valve mechanism for an internal combustion engine characterized by: (2) The valve operating mechanism for an internal combustion engine according to claim 1, wherein in the air cylinder, the elastic body has a bellows shape. (3) The valve mechanism for an internal combustion engine according to claim 1, wherein the air cylinder is provided with an upper air supply hole and a lower air supply hole. (4) In the air cylinder, when the piston is held at a position in contact with the upper inner wall of the air cylinder, a partial space is provided between the piston and the upper inner wall of the air cylinder in which compressed air is held. The valve operating mechanism for an internal combustion engine according to claim 1, further comprising a lower air supply hole. (5) The valve operating mechanism for an internal combustion engine according to claim 4, wherein in the air cylinder, the shape of the piston and/or the upper inner wall of the air cylinder is convex or concave.