JPH036803Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a partial valve train deactivation device for an engine valve train, and relates to a clutch engagement device for stopping or releasing a part of the valve train. To provide a small and simple spring pressure adjusting device for a coiled return spring involved in cutting.

[Prior art]

Generally, a part of the valve train is stopped operating in the following cases.

(1) Swirl is strengthened by stopping one of the double intake valves during startup or low-speed operation.

(2) One side of the double exhaust valve is stopped at startup to suppress heat escape.

(3) Reduce energy consumption by operating a multi-cylinder engine with fewer cylinders.
Reduce loss.

Therefore, when the basic structure of a device for stopping a part of the valve train is shown in FIG. - The driven side rocker arm 5 is interlocked and connected via the arm 3 and the clutch 4, and the clutch 4 is configured to be able to be turned on and off by a hydraulic cylinder 6 and a coiled return spring 100. This is a type in which the arm 5 is fitted onto a common rocker arm shaft 7.

The prior art of this type is
There is one related to No. 66317 (see Figures 9 and 10).

That is, in the prior art, a meshing clutch is formed on the opposing surfaces of both the rocker arms 3 and 5 on the driving side and the driven side, and the return spring 1 is inserted in the circumferential direction of the clutch 4.
00 are attached to release the clutch 4, and when the hydraulic pressure of the hydraulic cylinder 6 is low, the clutch 4 is disengaged by the return force of the spring 100, and conversely,
When the oil pressure is high, the clutch 4 is configured to engage against the return force of the spring 100.

[Problem that the invention attempts to solve]

However, in the above-mentioned prior art, a plurality of return springs 100 are attached in the circumferential direction of the clutch 4, and the return springs 100 are arranged in a planetary manner around the locker arm shaft 7 on the outer periphery thereof.
As a result, the outer diameter of the hydraulic cylinder 6 becomes larger, which not only increases the size of the valve deactivation device itself, but also makes it necessary to space the parts around the valve mechanism apart from each other due to the increased size. trying to make it larger.

The technical problem of this invention is to make hydraulic cylinders compact.

[Means for solving problems]

Means for achieving the above object will be explained below using FIGS. 1 to 8, which correspond to embodiments.

That is, in the present invention, the coiled return spring 100 is attached to the rocker arm shaft 7 in an externally fitted manner, and the rocker arm
Spring receiving portion 1 that does not move relative to the axial direction of the arm shaft 7
The spring wire insertion hole 103 is inserted into the rocker arm shaft 7.
The adjustment screw 101 is screwed into one end 106 of the spring wire insertion hole 103 so that it can be adjusted forward and backward, and the spring wire at the fixed end 104 of the coiled return spring 100 is opened. The wire tip 105 is formed to be oriented substantially parallel to the axial direction S of the Rocker arm shaft 7, and the spring wire tip 105 is inserted into the other end 1 of the spring wire insertion hole 103.
07 and receive it at the tip of the adjustment screw 101 to adjust the tension of the coil return spring 100 to the adjustment screw 101.
It is characterized by being configured to be adjustable.

[Effect]

The coiled return spring 100 is always biased in the direction of releasing the clutch 4, and when the hydraulic pressure of the hydraulic cylinder 6 is low, the elastic force of the spring 100 overcomes and the clutch 4 is released, and only the locking arm 3 on the driving side is released. It will be driven independently.

On the other hand, when the oil pressure of the hydraulic cylinder 6 becomes high, this oil pressure overcomes the elastic force of the spring 100, and the clutch 4 is connected to drive both the driving side and driven side rocker arms in parallel. .

In this case, by adjusting the adjustment screw 101, the retracting force of the return spring 100 can be increased or decreased, and the clutch 4
The oil pressure that starts turning on and off can be changed.

[Effect of idea]

Since the coiled return spring that biases in the direction against the hydraulic cylinder is attached to the Rocker arm shaft in an external fit, the wire portion of the spring is wrapped around the Rocker arm shaft in the circumferential direction, so that the Rocker arm Compared to the conventional technology in which a plurality of return springs are arranged in a planetary manner around a shaft, the outer diameter of the hydraulic cylinder is smaller, and the valve train deactivation device itself can be made smaller.

Furthermore, since the tip of the thin spring wire of the coiled return spring can be adjusted using an adjustment screw, the spring tension adjustment device can be made smaller than adjusting the winding portion of the spring.

Therefore, members around the valve mechanism can be arranged close to the hydraulic cylinder, and the entire engine can be made compact.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

Fig. 1 is a plan view of the area around the Rocker arm shaft, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a right side view of the coiled return spring, Fig. 4 is a plan view of the same spring, and Fig. 4 is a plan view of the spring. Figure 5 is a front view of the engine, Figure 6 is a longitudinal sectional front view of the vicinity of the Rocker arm shaft, Figure 7 is an enlarged longitudinal sectional front view of the vicinity of the hydraulic cylinder, and Figure 8 is a longitudinal sectional right side view of the main parts of the diesel engine. be.

Diesel engine E cylinder block 21
A cylinder 22 is formed in the center of the cylinder 22, and a piston 23 is fitted inside the cylinder 22 so as to be vertically slidable.

The cylinder head 24 and the head cover 25 are sequentially fixed above the cylinder block 21, two intake and exhaust ports 26 and 27 are opened in the cylinder head 24, and the double intake valves 28a and 28b are connected to the two intake ports. In addition, double exhaust valves 29, 29 are made to face the two exhaust ports 27 so as to be openable and closable, respectively.

A bracket 30 is attached to the upper end surface of the cylinder head 24.
A plurality of brackets are fixed, and a rocker arch is attached to the bracket 30.
The rocker arm shaft 7 is mounted on the rocker arm shaft 7, and a driving-side rocker arm 3 and a driven-side rocker arm 5 for air intake are fitted onto the rocker arm shaft 7 so as to be able to swing freely, and the rocker arms 3 and 5 are placed opposite each other. A clutch 4 is formed by meshing with the end face.

A valve drive camshaft 31 that is linked to the crankshaft is mounted on the left side of the cylinder block 21, and the valve drive camshaft 31 is linked to the drive side rocker arm 3 via a tappet 32 and a push rod 33.

The input part 34 of the driving side rocker arm 3 is connected to the upper end 33a of the push rod 33, and the output part 3 thereof is connected to the upper end 33a of the push rod 33.
5 can be brought into contact with one side 28a of the double intake valve, and the output part 3 of the driven side rocker arm 5
6 is configured to be able to come into contact with the other 28b of the double intake valve.

Therefore, the rotational force of the valve train camshaft 31 is applied to the intake cam 2.
After the movement is converted into vertical movement, the main drive side opening arm 3 is moved through the tappet 32 and the push rod 33.
is transmitted to the intake valve 28a and swings the intake valve 28a.
Drive to open and close.

In this case, when the clutch 4 is engaged, the driven side rocker arm 5 also swings in accordance with the driving side, driving the other intake valve 28 so that it can be opened and closed (that is, both valves are driven), but when the clutch 4 is disengaged, Driven side rocker
The arm 5 receives no input from the active rocker arm 3, stops the other intake valve 28b, and performs single-valve drive using only one intake valve 28a.

A hydraulic cylinder 6 for engaging and closing the clutch 4 is disposed between the left end of the driven side rocker arm 5 and the bracket 30, and is attached to the rocker arm shaft 7 so as to be externally fitted thereto.

The hydraulic cylinder 6 consists of a cylinder body 8, a piston 10, and an oil-tight cylinder membrane 15, and is installed through the center of the Rocker arm shaft 7 in a hydraulic oil chamber 11 formed so as to be surrounded by the oil-tight cylinder membrane 15. An oil feed hole 56 branched from the lubricating oil hole 55 is communicated with the lubricating oil hole 55 so that oil can be pumped into the hydraulic oil chamber 11 from the lubricating oil pump of the engine E.

On the other hand, a coiled return spring 100 is attached to the outermost cylinder body 8 of the hydraulic cylinder 6 so as to be always in the direction of disengaging the clutch 4 so as to resist the hydraulic cylinder 6. energize.

As shown in FIGS. 3 to 5, the return spring 100 is a left end portion 10 of a single-turn coil 108.
8a is extended rightward to form a fixed side end 104,
The tip portion is folded back in a V-shape along a horizontal plane to form a spring wire tip portion 105, and the tip portion 1
05 in a straight line to the right (see Figure 5, which is a front view).

In addition, the right end 108b of the coil 108 is folded back in a V shape while being aligned with the vertical plane, and the support side end 1
10, and the tip of this supporting end 110 is directed leftward.

On the other hand, a chevron-shaped spring receiving part 102 is formed above the bracket 30, and a spring wire insertion hole 103 is formed in the spring receiving part 102 along the longitudinal direction S of the rocker arm shaft.

The supporting end portion 110 of the coiled return spring 100 is suspended from the output portion 36 extending forward of the driven rocker arm 5.

In addition, the spring wire tip 105 of the coiled return spring 100 is inserted from the left side of the spring wire insertion hole 103, and the tip 105 is moved in the length direction S of the rocker arm shaft (that is, in the direction of expansion and contraction of the spring 100). At the same time, insert the adjustment screw 1 from the right side of the insertion hole 103.
01, and the tip of the screw 101 is brought into contact with the spring wire tip 105.

In this case, the coiled return spring 100 has the spring wire tip 105 on the fixed side, and the support side end 110 is pressed to the right more than in the natural state (see FIGS. 4 and 1). At the same time, the output portion 36 is attempted to be pulled back in the direction of the arrow P in an attempt to return the supporting end portion 110 to its original position.

Therefore, the return spring 100 always works in the direction of releasing the clutch 4, and by screwing in the adjustment screw 101, the urging force of the spring 100 is increased, and the screw 101
The biasing force can be reduced by loosening the clutch 4. (1) When the engine speed is low, the hydraulic pressure is low and the biasing force of the compression spring 60 overcomes the locking force on the driven side. Slide the arm 5 in the direction of arrow P to release the clutch 4 (see Figure 1).

Therefore, only the main drive side rocker arm 5 swings independently, and only one of the double intake valves 28a is driven as a single valve.

As a result, the intake port 2 on the side where the single valve is driven
Intake air is concentrated at 6, which strengthens the swirl and improves combustion efficiency.

(2) As the engine speed increases, the hydraulic pressure increases, overcoming the biasing force of the return spring 100 and sliding the driven side Rocker arm 5 in the direction of arrow Q.
Connect clutch 4 (see Figure 2).

Therefore, both the rocker arms 5, 3 on the driving side and the driven side swing, and both the double intake valves 28a,
Both valves 28b are driven.

As a result, intake air flows in from the two intake ports, improving air utilization and combustion efficiency.

On the other hand, as shown in FIGS. 2 and 3, the coiled return spring 100 supports both ends of the fixed side end 104 and the support side end 110 in a direction in which the coil 108 is closed from its natural state. Therefore, the support side end 110 is urged in the direction of arrow S (ie, counterclockwise) with the fixed side end 104 as the center.

Therefore, the driven side rocker arm 5 is always connected to the intake valve 3.
6 (however, this urging force is weaker than the valve closing force of the valve spring 112). As a result, (1) there is no valve clearance between the driven side rocker arm 5 and the intake valve shaft 114, which prevents the driven side rocker arm from wobbling;
It is possible to prevent the lift amount of the driven-side intake valve 28b from becoming smaller by the amount corresponding to the swing angle corresponding to the clearance, and it is possible to increase the intake time area of the intake valve 28b.

(2) If the clutch 4 is released while the locker arms 3 and 5 on the driving side and the driven side are driving both valves and pressing the intake valves 28a and 28b, the elastic force of the valve closing spring 112 The driven locking arm 5 tries to spring upward, but the biasing force of the return spring 100 is acting on the driven locking arm 5, so this springing force is suppressed, so that the return spring prevents the stopper from being thrown. Can serve as eyes.

As described above, the present invention attempts to reduce the outer diameter of the hydraulic cylinder 6 by attaching the coiled return spring 100 that resists the on/off action of the hydraulic cylinder to the rocker arm shaft 7 in an externally fitted manner. Although the present invention may be applied to a double intake valve train as in the above embodiment, it may also be applied to a double exhaust valve train or a reduced cylinder operation mechanism as described above.

[Brief explanation of the drawing]

1 to 8 are drawings showing an embodiment of the present invention, and FIG. 1 is a plan view around the Rocker arm shaft;
Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a right side view of the coiled return spring, Fig. 4 is a plan view of the same spring, Fig. 5 is a front view thereof, and Fig. 6 is a locking spring. Fig. 7 is an enlarged longitudinal sectional front view of the area around the hydraulic cylinder, Fig. 8 is a longitudinal sectional right side view of the main parts of the diesel engine, and Fig. 9 is a view equivalent to Fig. 6 showing the prior art. , FIG. 10 is an enlarged vertical sectional view of the vicinity of the clutch showing the prior art. DESCRIPTION OF SYMBOLS 1... Valve train, 2... Valve drive cam, 3... Drive side Locker arm, 4... Clutch, 5... Driven side Locker arm, 6... Hydraulic cylinder, 7... Locker arm shaft , 100... coiled return spring, 10
1...Adjustment screw, 102...Spring receiver, 103
... Spring wire insertion hole, 104 ... Fixed side end of 100, 105 ... Spring wire tip, 106 ... 103
One end of , the other end of 107...103.

Claims (1)

[Claims for Utility Model Registration] A driven side rocker arm 5 is interlocked and connected to a valve driving cam 2 of a valve train 1 of an engine E via a driving side rocker arm 3 and a clutch 4, and the clutch 4 is connected to a hydraulic cylinder 6. and a coiled return spring 100 so that the locker arm 3 on the driving side and the rocker arm 3 on the driven side can be turned on and off.
In a partial valve operation deactivation device for an engine valve train, in which the arm 5 is fitted onto a common Locker arm shaft 7, a coiled return spring 100 is fitted onto the Locker arm shaft 7 in a fitted manner, A spring wire insertion hole 103 is formed in a spring receiving portion 102 that does not move relative to the axial direction of the Rocker arm shaft 7 in a direction substantially parallel to the axial direction S of the Rocker arm shaft 7, and one end of the spring wire insertion hole 103 is formed. The adjustment screw 101 is fitted into the section 106 so that it can be adjusted forward and backward, and the spring wire tip 105 of the fixed end 104 of the coiled return spring 100 is aligned almost parallel to the axial direction S of the Rocker arm shaft 7. the other end 1 of the spring wire insertion hole 103.
07 and receive it at the tip of the adjustment screw 101 to adjust the tension of the coil return spring 100 to the adjustment screw 101.
A partial valve train deactivation device for an engine valve train, characterized in that it is configured to be adjustable.