JPH041285Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to an intake/exhaust valve actuation stop device for a variable cylinder internal combustion engine, and is particularly applicable to a valve gap between a rocker arm of a valve mechanism and an intake/exhaust valve. This invention relates to an intake/exhaust valve operation stop device that can be adjusted as desired.

[Prior Art] A device shown in FIG. 2 has been known as a device for stopping the opening/closing operation of intake and exhaust valves in a deactivated cylinder in a variable cylinder internal combustion engine. This intake/exhaust valve operation stop device a, as shown in the figure,
The fulcrum part d of the rocker arm c of the valve operating mechanism that opens and closes the intake/exhaust valve b is supported from the fixed system f by hydraulic pressure sealed in the plunger e.

When operating the intake/exhaust valve b, the fixed system f
Oil is sealed in the hydraulic chamber i of the plunger e from an oil supply path g provided in the plunger e through a check valve h, and the sealed oil pressure obtains a reaction force of the thrusting force transmitted from the push rod j to support the rocker arm c. As a result, the rocker arm c swings around the fulcrum d, and the intake and exhaust valves b are opened and closed. Also, when stopping the operation of intake/exhaust valve b,
When stopping the operation, check valve h is opened by needle valve k. As a result, the plunger e no longer receives the reaction force of the pushing up force of the push rod j, and the fulcrum d of the rocker arm c moves up and down, stopping the operation of the intake and exhaust valves b.

[Problems to be solved by the invention] By the way, in the conventional intake/exhaust valve actuation stop device a described above, the fulcrum portion d of the rocker arm c of the valve mechanism is supported by hydraulic pressure sealed in the hydraulic chamber i of the plunger e. , is supported by the hydraulic pressure sealed in the hydraulic chamber i of the plunger e, but the plunger e has a function (commonly known as a lash adjust function) that keeps the valve gap between the rocker arm c and the intake/exhaust valve b at O at all times. have. However, on the other hand, the hydraulic reaction force within the hydraulic chamber i of the plunger e is transmitted to the intake/exhaust valve b, reducing the set force of the valve spring l. Furthermore, the plunger e is provided with a return spring m in order to increase the responsiveness of the lift speed of the fulcrum part d of the rocker arm c when the operation of the intake/exhaust valve b is stopped. The biasing force m also acts to reduce the set force of the valve spring l. and valve spring l
When the set force of B is lowered, when an attempt is made to obtain exhaust braking force by closing the butterfly valve installed in the exhaust pipe, the back pressure in the exhaust pipe increases and the sealing performance of exhaust valve B is reduced, resulting in insufficient A problem arises in that sufficient exhaust braking force cannot be obtained.

On the other hand, if the intake/exhaust valve b moves irregularly, the fulcrum part d of the rocker arm c will be pulled down below its specified position, and there will be excess oil in the hydraulic chamber i of the plunger e. may be sucked in and the intake/exhaust valve b may not be completely closed thereafter. When this happens, the performance of the internal combustion engine decreases, and in the worst case, the intake and exhaust valves
There was also the risk that the engine would interfere with the piston and cause damage to the engine.

In order to solve the above-mentioned problems, an inner sleeve n is provided between the plunger e that moves up and down and an inner sleeve n that is fitted and inserted into the plunger e and serves as a supporting side, so that the plunger e can be extended to its maximum extent. Snap spring (not shown) to regulate the length of time
There is known an intake/exhaust valve actuation stop device that prevents the fulcrum d of the rocker arm c from being supported below its specified position (Japanese Patent Laid-Open No. 59-23020, etc.). .

However, when such a snap ring is provided, the lash adjust function of the plunger e is canceled and a valve gap occurs in the valve mechanism, making it necessary to adjust the valve gap during assembly.

However, the inner sleeve n is not fixed to the fixed system f, and the plunger e has a structure in which a reaction force is obtained only when the inner sleeve n comes into contact with the fixed system f. Therefore, even if an attempt is made to adjust the valve gap with the plunger e and the inner sleeve n extended to the maximum extent, the plunger e and the inner sleeve n will become one and fall downward by the valve gap. For this reason, the valve gap ended up being formed between the inner sleeve n and the fixing system f, making it extremely difficult to adjust it.

[Purpose of the invention] The present invention has been devised in view of the above-mentioned problems and to effectively solve them.

The purpose of this invention is to stop the operation of the intake and exhaust valves of a variable cylinder internal combustion engine by creating a valve gap between the rocker arm of the valve mechanism and the intake and exhaust valves, and by easily adjusting the valve gap. The goal is to provide equipment.

[Summary of the invention] In order to achieve the above object, the present invention includes a plunger that hydraulically supports the fulcrum part of the rocker arm that opens and closes the intake and exhaust valves from a fixed system, and a plunger that hydraulically supports the fulcrum part of the rocker arm that opens and closes the intake and exhaust valves, and the plunger that moves the fulcrum part up and down. The apparatus includes an oil supply and discharge means for supplying and discharging oil, and a valve gap adjustment means that adjustably regulates the lowest position of the fulcrum part from a fixed system to create a valve gap between the rocker arm and the intake/exhaust valve. This constitutes an intake/exhaust valve operation stop device.

[Embodiment] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a side cross section of the intake/exhaust valve operation stop device 1 according to the present invention. provided.

The intake/exhaust valve actuation stop device 1 supports a rocker shaft 4, which serves as a fulcrum for a rocker arm 3 of a valve train mechanism 2. When opening/closing the intake/exhaust valves 5, it hydraulically receives thrust force from a bushing rod 6. The rocker shaft 4 is supported at a specified position, and the rocker arm 3 is reciprocated around the rocker shaft 4 to open and close the intake and exhaust valves 5.

On the other hand, when stopping the opening/closing operation of the intake/exhaust valve 5, the hydraulic pressure is released to move the rocker shaft 4 up and down with the thrust force of the push rod 6, absorbing the thrust force, and opening/closing the intake/exhaust valve 5. Stop the opening/closing operation.

That is, as shown in the figure, the intake/exhaust valve actuation stop device 1 includes a plunger 8 that hydraulically supports the rocker shaft 4 from a fixed system 7 such as a cylinder head;
An oil supply/discharge means 10 that supplies and discharges oil into a hydraulic chamber 9 formed in the plunger 8 to freely move up and down the rock shaft 4, and a fixing system 7 that adjustably regulates the lowest position of the rock shaft 4. The valve gap adjusting means 11 generates a valve gap α between the rocker arm 3 and the intake/exhaust valve 5.

The plunger 8 has a cylindrical shape with a bottom, and at its lower end there is a support 1 that pivotally supports the rock shaft 4.
2 is attached, and the upper end side is spaced apart from the fixing system 7. An inner sleeve 13 is provided on the upper end side of the plunger 8 and is inserted into the inner peripheral surface of the plunger 8 so that its upper edge abuts against the fixing system 7. The above-mentioned hydraulic chamber 9 is formed in the plunger 8 by the inner sleeve 13, and when the hydraulic pressure in the hydraulic chamber 9 is released, the plunger 8 slides up and down with respect to the inner sleeve 13. It is designed to move up and down. Further, an outer sleeve 14 is provided on the outer circumferential surface of the plunger 8 to guide its vertical movement, and the outer sleeve 14 is fixed to the fixing system 7 via a cylindrical holder 15. The outer sleeve 14 is screwed into the inner circumferential surface of the holder 15, and the holder 15 is screwed into a recess 16 provided in the fixing system 7 to move up and down relative to the fixing system 7. It has become freely possible.

The oil supply means 10 supplies oil into the hydraulic chamber 9 through a check valve 17 provided at the bottom of the inner sleeve 13, a needle valve 25 for opening the check valve 17 as appropriate, and the check valve 17. It is composed of an oil gear rally 18 for supplying and discharging oil.

The oil gear gallery 18 is composed of an oil supply passage 19 provided in the fixed system 7 and an oil supply chamber 20 defined in the upper part of the recessed part 16. A port 21 is provided. The check valve 17 is provided on the hydraulic chamber 9 side at the bottom of the inner sleeve 13, and opens the supply/discharge port 22 when the plunger 8 moves downward to supply oil from the oil supply chamber 20 side into the hydraulic chamber 9. It's becoming like that. Further, the cylinder head, which is the fixing system 7, is formed with a through hole 24 extending from its upper surface 23 toward the inside of the inner sleeve 13 in the concave portion 16. The needle valve 25 is provided therethrough. A solenoid 26 for vertically extending and retracting the needle valve 25 is provided on the upper surface 23 of the cylinder head, which is the fixed system 7.
is energized when the cylinder is stopped to extend the needle valve 25 downward and press the check valve 17 to open it. That is, when the check valve 17 is opened, the hydraulic pressure in the hydraulic chamber 9 is released, and the plunger 8 is no longer able to support the thrusting force of the bushing rod 6, causing oil to flow into the hydraulic chamber 9 as the pushrod 6 moves up and down. While supplying and discharging air, the rock shaft 4 is moved up and down to absorb the uplifting force and stop the opening/closing operation of the intake/exhaust valves 5.
Reference numeral 27 denotes a return spring provided to increase the response speed when the plunger 8 descends.One end of the return spring is locked to the fixing system 7 via the outer sleeve 14 and the holder 15, and the other end is connected to the plunger 8. A flange portion 28 provided with an enlarged diameter at the lower end of the
It is locked to.

By the way, the feature of the present invention is that the lowest position of the shaft 4, which is moved up and down by the plunger 8, is regulated and locked by the fixed system 7, and the lowest position can be arbitrarily adjusted to control the intake/exhaust valve. A valve gap adjustment means 11 is provided between the rocker arm 5 and the rocker arm 3 to create a valve gap α.

In the case of this embodiment, the valve gap adjusting means 11 is composed of the above-mentioned holder 15 and a locking piece 29 of the flange portion 28 of the plunger 8 formed on the holder 15.

As shown in the figure, a locking piece 29 is provided at the lower end of the holder 15 and extends radially inward to lock the lower surface 30 of the flange portion 28 of the plunger 8 . As mentioned above, the holder 15 is screwed into the recess 16 provided in the cylinder head, which is the fixing system 7, and by rotating the holder 15, the position of the locking piece 29 relative to the fixing system 7 (i.e., the position of the locking shaft 4) is adjusted. (lowest position) can be adjusted as desired. The holder 15 is securely fixed to the fixing system 7 with a lock nut 31.

That is, as is clear from the above explanation, the intake/exhaust valve actuation stop device 1 of the present invention regulates the lowermost position of the rocker shaft 4 (the fulcrum of the rocker shaft 3) from the fixed system using the valve gap adjusting means 11 to set it at a specified position. to be locked. This makes it possible to provide a valve gap α between the rocker arm 3 of the valve mechanism and the intake/exhaust valve 5.

Further, since the valve gap adjusting means 11 can freely adjust the lowest position of the rocker shaft 4 to a specified position, it is possible to arbitrarily adjust the value of the valve gap α, and the adjustment can be easily performed using a thickness gauge. It becomes like this.

On the other hand, if a valve gap α is generated in the valve mechanism 2, the reaction force of the support hydraulic pressure of the plunger 8 and the biasing force of the return spring 27 will not act on the intake/exhaust valve 5, and the set force of the valve spring 32 will be reduced. It will be possible to prevent this from occurring. This prevents the exhaust braking force from decreasing, and since the intake/exhaust valves 5 are reliably closed, the performance of the internal combustion engine does not deteriorate, and the intake/exhaust valves 5 and the piston There is no risk of damage to the engine due to interference.

Note that the valve gap adjustment means 11 is the valve gear mechanism 2.
from the lower fixation system (not shown) to the locking arm 3.
The lowest position may be regulated.

[Effects of the invention] In summary, the present invention provides the following excellent effects.

(1) Since the lowest position of the rocker arm fulcrum is regulated and locked by the valve gap adjustment means from the fixed system, a valve gap can be created between the rocker arm and the intake/exhaust valve.

(2) Since the valve gap adjusting means can freely adjust the lowest position of the rocker arm to a specified position, the valve gap value can be easily adjusted.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a preferred embodiment of the intake/exhaust valve operation stop device according to the present invention, and FIG. 2 is a side sectional view showing a conventional intake/exhaust valve operation stop device. In the figure, 1 is an intake/exhaust valve operation stop device, 3 is a rocker arm, 4 is a rocker shaft that serves as a fulcrum of the rocker arm, 5 is an intake/exhaust valve, 7 is a fixed system, 8 is a plunger, 10 is an oil supply/discharge means, 11 is a valve gap adjusting means.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A plunger that hydraulically supports the fulcrum part of the rocker arm that opens and closes the intake and exhaust valves from a fixed system, and a plunger that supplies and discharges oil to the plunger to move the fulcrum part up and down. The present invention is characterized by comprising an oil supply/discharge means and a valve gap adjustment means for adjusting the lowest position of the fulcrum part from a fixed system to create a valve gap between the rocker arm and the intake/exhaust valve. Intake/exhaust valve operation stop device. (2) The scope of the above utility model registration claim comprises a holder in which the valve gap adjusting means is screwed into a fixed system so as to be movable up and down, and has a locking piece extending from the lower end of the holder to lock the plunger. The intake/exhaust valve operation stop device according to item 1. (3) The intake/exhaust device according to claim 2 of the utility model registration claim, wherein the holder has a cylindrical shape surrounding the circumference of the plunger and has a lock nut for fixing the holder to a fixed system. Valve stop device.