JPS59200006A - Pump style hydraulic tappet valve of internal combustion engine - Google Patents

Abstract

PURPOSE:To make opening/closing timing of a valve controllable independently by enabling pistons of two ports provided on plunger barrels to be in relatively moved in turn and also enabling a plunger with two leads to be moved in turn with respect to the appropriate barrel. CONSTITUTION:A plunger 2 driven by a cam 1 makes a reciprocating movement in a fixed type plunger barrel 26 and a rotary type plunger barrel 6 and, through discharging working oil from a pump chamber 20, drives a piston 30 which causes a valve 33 to make a reciprocating movement. SInce the barrel 6 and the plunger 2 are turned by means of a rack 5 and a rack 4 respectively timings of coincidence of a control lead 10 with a working oil entrance port 7 at the valve opening time and coincidence of a control lead 9 with a working oil return port 13 at the valve closing time can be controlled independently according to engine speed, load or the like. Thus, the timing of opening/closing of the valve can be controlled independently.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pump-type hydraulic valve system for an internal combustion engine that variably controls opening and closing timing.

Most conventional intake/exhaust valve drive devices for internal combustion engines are mechanical valve drive mechanisms using a valve arm system that connects a camshaft, tappet, and push rod via a valve arm nut. There was no mechanism to change the timing of opening and closing.

Furthermore, since moving objects with large masses such as push rods and valve arms are continuously connected, the influence of inertial force is large, and the installation locations of cams and the like are restricted.

Therefore, in a hydraulic valve operating system for opening and closing the intake and exhaust valves of a diesel engine, Japanese Patent Application Laid-Open No. 56 (1982) relates to a valve timing change device for a diesel engine that automatically changes the opening and closing timing of the intake and exhaust valves during machine rotation. The invention of No.-44406 has been made.

In this case, since two leads are formed on the plunger, the barrel is integral and not divided, and each lead is not independent, it is not possible to compensate for the effects of other operations.

Furthermore, in the invention of JP-A-56-444.05, which was made for the same purpose in a similar hydraulic valve train,
Since a separate valve-opening control piston is required, the structure is complicated and its durability is poor.

Furthermore, for the same purpose, the invention of Japanese Patent Publication No. 46-22962 relates to a valve device for an internal combustion engine using a hydraulic valve train, and the invention of Japanese Patent Publication No. 47-22726 relates to a valve opening/closing timing adjustment device in a hydraulic valve train. Although some inventions have been made, in these cases, only the valve closing timing is adjusted, and the valve opening/closing timing is not adjusted.

SUMMARY OF THE INVENTION Therefore, the present invention aims to provide a pump-type hydraulic valve system that can control the opening and closing timing of intake and exhaust valves. This was done with the ultimate purpose of improving the engine performance such as fuel efficiency and exhaust color by setting the timing of the engine.

That is, the pump-type hydraulic valve device of the present invention uses hydraulic oil generated by a plunger driven by a cam to open and close the intake and exhaust valves and to control the timing of the opening and closing by using two glue rods provided on the plunger. 2 installed in the plunger barrel
In a pump-type hydraulic valve system that is variable by changing the phase difference between the two boats, the plunger barrel is formed of two pieces, an upper fixed plunger barrel and a lower rotary plunger barrel, and The present invention is characterized in that a rack for rotating the plunger and a rack for rotating the rotary plunger barrel are provided, respectively.

The present invention will be described in detail below with reference to the drawings, in which the same parts in each embodiment are designated by the same part numbers.

First, FIG. 1 is an overall vertical cross-sectional view of a pump-type hydraulic valve system for an internal combustion engine according to an embodiment of the present invention, and FIGS. 2 and 3 are simplified vertical cross-sectional views of the main parts of FIG. 1. .

First, the hydraulic pressure generated by the plunger 2 driven by the force M 1 through the tappet 23 with the tappet roller 24 pushes down the operating piston 60 via the high pressure pipe 25, thereby causing the intake and exhaust valves 6 of the internal combustion engine to 6.
2, the intake/exhaust valve 66 is pressed down against the spring force of
The opening and closing operations are performed.

Next, the plunger 2 is provided with a glue 9 for controlling the valve closing time and a glue 10 for controlling the valve opening, and the upper fixed type is divided into two parts. By changing the phase difference between the hydraulic oil return boat 16 provided on the plunger barrel 26 and the hydraulic oil inlet boat 7 provided on the lower rotary plunger barrel 6, the timing of opening and closing of the intake and exhaust valves 66 can be varied. I try to do that.

That is, the upper glue 9 and the fixed branjar 2
The valve closing of the intake/exhaust valve 63 is controlled by the phase difference with the hydraulic oil return boat 16 of the rotary plunger barrel 6, and the valve is opened by the phase difference between the lower gate 10 and the hydraulic oil inlet boat 7 of the rotary plunger barrel 6. It is designed to control the timing.

Furthermore, a rank 5 for rotating the rotary plunger barrel 6 is provided in addition to the rack 4 for rotating the plunger 2 via the pinion sleeve 6, and by rotating them independently, two glue rods 9 are provided. , 10 and the hydraulic oil return boat 16 and the hydraulic oil inlet boat 7 can be corrected independently.

At this time, depending on the rotation of the rotary plunger barrel 6, there is no change in the phase difference between the upper lead 9 and the hydraulic oil return boat 16, but when the plunger 2 rotates, the lower lead 10 Since the lower steering wheel also rotates, the phase difference between the lower steering wheel 10 and the hydraulic oil-filled boat 7 is affected, so it is necessary to rotate the hydraulic oil-filled lower to correct the original phase difference.

In addition, in FIG. 2, a check valve 11 is provided above the space 20 at the top of the plunger 2.

Therefore, as a control when the valve is opened, by pulling the rack 5 as shown in FIG.
, the hydraulic oil inlet boat 7 also rotates, and the lead 10
The phase difference between the

As the prestroke increases, which is zero at the beginning, the hydraulic oil becomes [1:,
This causes a delay in the movement of the actuating piston 60.

Next, as for the valve closing control, when the cam 1 is in the maximum lift state in Fig. 3, the hydraulic pressure is maintained at the upper part of the operating piston 60, and the intake and exhaust valves 66 are also in the open state shown by the solid line. maintain.

Therefore, when the cam 1 reaches the lift lowering section, the hydraulic pressure disappears, and as a result, the valve spring 62 causes the operating piston 60 to become the driving side, and the hydraulic oil is passed through the hydraulic oil return boat 1 to the plunger. 2 into the space 20 at the top.

However, if there is a phase difference between the lead 9 and the hydraulic oil return boat 16 as shown in FIG. It is.

Therefore, as shown in FIG. 3, when the phase difference is maximum, the oil confinement holding period is in effect, which is the hydraulic locking period.

On the other hand, at 1 o'clock when the closing time of the intake/exhaust valve 66 is changed, by pushing the rack 4, the plunger 2 is moved to the opposite time 81.
The phase difference between the reed 9 and the hydraulic oil return boat 16 decreases, the hydraulic lock period decreases, and as a result, the valve closing period of the intake/exhaust valve 63 is accelerated.

Here, as the plunger 2 rotates, a change occurs in the phase difference between the steering wheel 10 and the hydraulic oil inlet boat 7, and if correction is necessary, push the rack 5 and rotate the rotary plunger barrel 6 to correct it. .

Note that the valve opening period of the intake/exhaust valve 66 during actual low load is delayed, and the valve closing timing is advanced, thereby reducing the overall valve opening period.

Here, the pump-type hydraulic valve system of this embodiment]
In order to reduce the valve opening period under low load, first rotate the plunger 2 in the rack 4 in the counterclockwise direction when viewed from the - side, and the valve closing timing will be t, I, and 3
The phase difference in the diagram becomes smaller.

At this time, since the plunger 2 is rotating counterclockwise, the relationship between the lead 10 and the hydraulic oil boat 7 is such that the prestroke increases, so there is a delay when the valve opens. , correction by rank 5 is actually not necessary.

As described in -1-, the positions of the leads 9 and 10 of the plunger 2 in the plunger 2 have a significant effect on the valve opening/closing timing, so it is necessary to process them accurately. Therefore, in the present invention, leads 9 and 10 are
We were able to accurately determine the location of That is, the fourth
Figures (a), (b).

As shown in (c) and (d), the method of machining the lead 9 will be described. An annular groove 64 is machined in the plunger 2.

34
If the point of intersection with the lower end of is denoted by ``2'', this point ``2'' can be easily determined on the outer periphery of the plunger, so the starting point of the lead 9 becomes clear and the lead 9 can be accurately processed into the plumber 2. A groove 65 similar to the groove 64 is also provided for the guide 10.
By providing the lead 9, it is possible to accurately process the plunger 2 into the plunger 2.

The pump type hydraulic valve system i″i of the first embodiment will be described below.

To give a detailed explanation of the operating principle, first, in Fig. 2, the stroke of the working piston 60 when the free stroke at the beginning of the lift of the working piston 60 is set to zero and the oil 1 bottom lock period is set to the maximum, that is, the stroke of the working piston 60, that is, the intake/exhaust stroke. A diagram of the lift H of the valve 66 is shown in FIG.

Here, the working piston 60 is pushed by incompressible working oil.
starts to lift almost without delay, and since the diameter of the plunger 2 and the diameter d of the working piston 60 are D>d, the lift of the working piston 60 is (D/d) compared to the plunger 2.
2 Increase.

That is, '+=H(1×(D/d)2).

Here, the lift H6 is the maximum lift in the lift diagram of the drive unit by the cam 1, that is, the plunger 2. The lift on the operating piston 60 side is limited to H, which is smaller than the above-mentioned lift H1.

At this time, the operating piston 60 is limited to the lift H, or
The remaining oil corresponding to H and -H, which would normally be lifted to Hl, is discharged by a relief valve 61 provided in the operating piston filter 0.

Next, at the time of full lift, the cam 1 has a shape consisting of points a, b, and c in FIG. 5, which maintains the full lift at the circular portion at the top due to the characteristics of its profile after the full lift.

When the entire lift section inside the term ends, the section after point C begins, which has the same profile as the lift rising section but decreases in the opposite way.

When the cam 1 is applied to the lift reduction section and the plunger 2 begins to descend, the hydraulic pushing force by the plunger 2 disappears, and conversely, the operating piston 30 becomes the driving side due to the spring force of the valve spring 62 shown in FIG. Attempts to push hydraulic oil toward plunger 2.

However, since there is a reverse +1 valve 11 in the space 20 at the top of the plunger 2, the hydraulic oil flows through the bypass passage 12 in the immediate vicinity, via the hydraulic oil return boat 16, and the communication holes 17 and 19. It attempts to return to the space 20 shown in Figure 3, but cannot return until it hits the hydraulic oil return boat 16 that communicates with the valve closing control glue 9 or the plunger 2 of the bypass passage 12. Until the plunger 2 descends, the actuating piston 60 stops moving and the intake and exhaust valves 66 also remain open, which is a so-called oil confinement holding period or hydraulic lock period.

Therefore, the pre-stroke at which the valve opening control lead 10 and the hydraulic oil inlet boat 7 coincide is Omm, and the difference between the valve closing control lead 9 and the hydraulic oil return 7Jf-to 16 is Omm. When the phase difference is at its maximum value, the opening period of the intake and exhaust valves 66 is at its maximum, which is a high load state, and here the valve opening angle is set to θ0.

Next, when reducing the valve opening period by delaying the valve opening timing, if the valve closing timing remains unchanged and the rotary plunger barrel 6 is rotated clockwise by subtracting rank 5, , the hydraulic oil inlet boat 7 also moves in the same direction, and the valve opening control lever 10 and the hydraulic oil inlet boat 7 change their positions relative to each other, producing a prestroke Ps as shown in FIG.

In this case, it is assumed that the plunger 2 does not rotate at 1/X, and the hydraulic oil inlet boat 7 moves in position as shown by the arrow.

When the pre-stroke Ps occurs in this manner, the operation of the working piston 60 shown in FIG. 2 becomes as shown in FIG. 7.

That is, while the cam 1, that is, the plunger 2 is rising by the prestroke Ps, the hydraulic oil is not compressed.

After the plunger 2 is lifted by the prestroke Ps, the hydraulic oil inlet boat 7 is closed by the valve opening control board 10, and the hydraulic oil is compressed and the working piston 60 is operated.

In FIG. 7, point a' is delayed by Δθ compared to FIG. 4, and as a result, the valve opening angle of the intake and exhaust valve 66 is reduced to θ−Δθ.

Furthermore, if you want to shorten the valve opening period by advancing the valve closing timing, keep the valve opening timing unchanged and press the rack 4 in Figure 3 to rotate the pinion sleeve 6 counterclockwise when viewed from the upper mi force). Since the plunger 2 similarly rotates counterclockwise when viewed from the top in conjunction with the on-sleeve B, the valve closing timing control lever 9 also rotates, and its relative position with the hydraulic oil return boat 16 changes.

That is, when the value of the phase difference at the uppermost position of the plunger 2 decreases, and the phase difference in the operation of the operating piston 60 decreases to h' as shown in FIG. 8, the hydraulic lock period decreases compared to when h. However, the valve closing timing is advanced by Δθ1, and the valve opening angle of the intake and exhaust valve 66 is reduced to θ−Δθ1.

However, since the plunger 2 rotated counterclockwise when viewed from the top, the valve opening timing control glue 10
The relative position between this and the hydraulic oil port 7 has changed in the direction of increasing the prestroke.

When restoring the valve opening timing, correction is made by pushing the rank 5 so that the rotary plunger barrel 6 rotates counterclockwise when viewed from the top.

This correction amount allows the rack 5 to be pushed in as much as the rack 4 is pushed in, and since the number of teeth of the rotary plunger no-marrel 6 and the binion sleeve 6 is the same as the number of modules, the stroke of rank 5 and the binion sleeve 6 are the same. The rotation angle matches.

In the pump-type hydraulic valve device of the double-lead type valve opening/closing independent control type according to the first embodiment described above, the plunger barrel is divided into a fixed type and a rotary type, and the rotary type plunger barrel 6 is rotated. The effect of the operation can be corrected.

Generally, when the load is low, the opening timing of the intake and exhaust valves 63 is delayed and the opening timing is advanced to shorten the overall valve opening period. However, in the timing change in the first embodiment, the plunger 2 is If you rotate it and advance the valve closing timing,
Since the valve opening timing is delayed due to this influence, there is actually no need for correction.

Next, FIG. 9, FIG. 10, and FIG. 11 each show a pump type hydraulic valve system according to each embodiment of the present invention, which has almost the same configuration and function as Embodiment 1, and will not be described here. Only the differences will be explained.

First, in the second embodiment shown in FIG. 9, there are two plungers 2 for an intake valve indicated by A and an exhaust valve indicated by B for each cylinder of an internal combustion engine, and their fixed plunger barrel 2.
6 and rotary plunger versill 6 etc., it is an integrated type of intake and exhaust type, which is more compact than Embodiment 1, and further improves the supply of hydraulic oil from one location. .

Next, in the third embodiment shown in FIG. 10, a rank hole is provided in each rack 4, 5 of the apparatus of the second embodiment in the middle of each plunger 2, and one rack 4, 5 each has two rotations. The hydraulic plunger harrell 6 and the plunger 2 are moved, and the hydraulic oil boat 7 is also placed in one place for dual use for intake and exhaust as well as for the exhaust valve. Furthermore, the number of parts is reduced and the device itself is simplified.

In addition, in the third embodiment shown in FIG. 11, the racks 4 and 5 in the second embodiment are divided into halves at the center, and while the rack holes are used for dual purposes, each rack 4 and 5 is made into an independent integrated air intake and exhaust system. This is a single-rack type that also has rack holes.

Therefore, in an internal combustion engine to which the pump-type hydraulic valve system of the present invention is applied, the valve opening/closing period control of the intake and exhaust valves is made OJ function, and the opening/closing timing can be changed, so that the opening/closing timing can be changed according to the load and rotation speed of the engine. The most appropriate timing can be set, which has the effect of improving engine performance such as fuel efficiency and exhaust color.

In addition, the opening and closing control of the intake and exhaust valves can be controlled independently by two ranks, and the valve opening and closing control section is centrally located in the plunger pump section, which saves space and allows for rank control. Another advantage is that the actuator is easy to control.

Furthermore, since the control mechanism is concentrated in the pump section as described above, it is possible to reduce the size and weight of the entire device.

[Brief explanation of drawings]

FIG. 1 is an overall vertical sectional view of a pump-type hydraulic valve system for an internal combustion engine according to an embodiment of the present invention, and FIGS.
Simplified vertical cross-sectional view of the main part of the figure, Fig. 4 (a), (b), (C
) and (d) are respectively side views of the plunger, (a) an enlarged view of part A in the figure, an explanatory diagram of the starting point of the lead, and (C) I in the figure.
-1 sectional view, FIG. 5 shows the lift diagram of the plunger by the cam at the beginning of the lift of the working piston in FIG. 1, and the intake/exhaust valve operation diagram by the working piston, and FIG. FIGS. 7 and 8 are side views of the main parts showing the relative positions of the oil inlet boat and the valve opening control lead, and FIGS. 7 and 8 are diagrams similar to FIG. 10 and 11 are overall vertical cross-sectional views of pump-type hydraulic valve systems according to embodiments of the present invention, respectively, with FIG. 9 showing the second embodiment, FIG. 10 showing the third embodiment, and the first embodiment.
FIG. 1 shows the fourth embodiment. 1...Cam, 2...Plunger, 4, 5...Rack, 6...Rotary blank shirt rail, 7...Hydraulic oil inlet bow I, 9-Lead for control when valve is closed , 10...Lead for valve opening control, 16...Hydraulic oil return boat, 26
・Rotary plunger barrel, 66 ・Intake and exhaust valve. Agent: Patent Attorney Shin Ogawa − Patent Attorney Ken Noguchi Patent Attorney Kazuhiko Saishita Figure 3, Figure 4L21

Claims (1)

[Claims] The hydraulic fluid generated by the plunger driven by the cam G controls the opening and closing of the intake and exhaust valves and the timing of the opening and closing by adjusting the phase difference between two leads installed on the plunger and two boats installed on the plunger barrel. In a pump-type hydraulic valve system that is variable by changing the plunger, the plunger barrel is formed of two parts, an upper fixed plunger barrel and a lower rotary plunger barrel, and a rank for rotating the plunger and a rotary plunger barrel for rotating the plunger. A pump-type hydraulic valve device for an internal combustion engine, characterized in that each rank is provided to rotate a plunger barrel.