JPS5879638A - Valve driving device provided with idle function - Google Patents

Abstract

PURPOSE:To simplify construction of a device, by comprising a rock transmission mechamism in one end of a cam follower, constituting a pivotally supporting mechamism in the other end of the cam follower from a lash adjuster and shutting off a pressure oil supply passage to the lash adjuster in idle operation of valve opening. CONSTITUTION:Valve opening driving force is applied to a valve body 5 by rocking motion of one end of a cam follower 19 through a transmission mechanism, contained with the first and second meshing members 10, 11, and the transmission mechanism is controlled by a control rod 15, moved in accordance with a loaded condition of an engine, to perform active and idle operation of the valve body 5. While a pivotally supporting mechanism, pivotally supporting the other end of the cam follower 19, is constituted by a piston plunger 21, slidably inserted into a control cylinder 22 and internally provided with a pressure oil passage 21a. Further the pressure oil passage 21a is communicated to a pressure oil supply passage 24, opened to a side wall of the control cylinder 22, and the pressure oil supply passage 24 is communicated to a hydraulic pressure source via a control valve (not shown in the drawing), opened and closed interlocking to the control rod 15, then the pressure oil supply passage 24 is shut off in idle operation of valve opening to suppress collision of cam 18 with the cam follower 19.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pulp drive device with a valve stop function for an internal combustion engine.In order to improve the high-speed performance of an internal combustion engine, a plurality of intake valves or exhaust valves are provided, and at high speed, the plurality of intake valves or exhaust valves are provided. A system has been proposed in which the intake valve or exhaust valve canopy is activated, and a part of the intake valve or exhaust valve is deactivated at medium or low speeds. (As an example of a lubricating device, for example, JP-A-54-
Conventionally, a valve drive device equipped with such a stop function disclosed in Japanese Patent No. 36415 has had a problem in that the structure for the stop function is complicated and has poor durability.Therefore, an object of the present invention is to The object of the present invention is to provide a valve driving device having a simple structure and high durability.

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

1 to 4 show an arrangement in which a loop drive (according to the invention) is provided in a cylinder block l.

The cylinder block IKU is provided with an intake or exhaust passage 2, which communicates with a combustion chamber 3, as in the conventional cylinder block. An on-off valve 4 that functions as an intake or exhaust valve is provided at the opening of the intake or exhaust passage 2 to the combustion chamber 3, and the valve body 5 of the on-off valve 4 is slidably inserted into the loop guide 6.
The valve body 5 is connected to the tappet guide hole 7 together with the valve guide 6, and is opened and closed by a spring 9 compressed between the retainer 8 connected to the top portion 5a by a retainer 8α and the bottom wall surface of the tappet guide hole. Valve 4 is energized to close. A first engaging member lO is slidably fitted into the opening of the tappet guide hole 7, and a bottom projection lOα of the first engaging member 10 is in contact with the top portion 5α of the valve body 5. A second meshing member 11, which is combined with the first meshing member 10 to form a valve driving force transmission mechanism, is fitted into the first meshing member 10 at its cylindrical portion 11a so as to be rotatable with each other, The shape of the first and second engaging members IQ, 11 is particularly apparent from FIG. 4. First meshing member 10
It consists of a bottom cylindrical skirt part 10α surrounding the top part 5α of the fl valve body 5 and an upper engaging part 1t)b, and the upper engaging part lOb is formed to have a smaller diameter than the bottom cylindrical skirt part 10α, forming a stepped part 10G. This step 10e and the second
A return spring 13 is provided between the meshing member 11 and the meshing member 11 via a wonger ring 121i, and biases the first and second meshing members 10 and 11' () in a direction away from each other. In the transmission mechanism including the first and second meshing members configured in this way, the first and second meshing members 10
, 11 are in relative angular positions where they can mesh with each other, and when a driving force is applied, the first and second meshing members 10, 1
1 are designed to mesh with each other as shown in FIG. 0 control rod 15, which is provided with a control rod 15 that slidably carries the clamping member 14 and is movable in a direction perpendicular to the axis of rotation of the second engaging member 11;
A pair of collar members 16α are provided on each side of the clamping member 14,
166 is fixed, and the collar members 16g, 16&
A pair of compression springs 17α is provided between the holding member 14 and the holding member 14.
, 176 are provided to connect the clamping member 14 to the collar member 16a.
#0 control rod 1 maintained at approximately the center of 166
5 is a cam follower which is adapted to be moved by an electromagnetic solenoid (not shown) or the like according to the load condition of the engine, and which responds to the cam 1B which rotates in accordance with the rotation of the crankshaft (not shown). I19 contacts the second meshing member 11 at one end and applies a valve opening driving force to the valve body 5 via the above-described transmission mechanism. Note that one end of the cam follower 19 is guided by a guide member 20 so as to be in constant contact with a predetermined position of the second meshing member. The other end of the cam follower 19 is pivotally supported by a spherical head of a piston plunger 21 constituting a run sea adjuster. The piston plunger 21 is slidably inserted into a control cylinder 22 fixed within the cylinder block l. , has hydraulic passages 21a f penetrating inside.

The hydraulic pressure m21a has one end open on the side surface of the piston plunger 21 and the other end open on the bottom surface of the piston plunger 21. A check valve 23 is formed at the bottom opening of the hydraulic path 21a. - the side opening of the hydraulic pressure path 21α is the hydraulic pressure supply path 2 opened in the side wall of the control cylinder 22;
The zero hydraulic pressure supply path which can communicate with the control rod 15 communicates with the hydraulic pressure source via a control valve 25 that is opened and closed by a valve body 15α that is interlocked with or integrated with the control rod 15. Therefore, when the control rod 15 is moved and the valve is in the inactive state, the hydraulic pressure supply 24 is cut off and the hydraulic pressure supply to the tappet mechanism is cut off, and the piston plunger 21 of the tappet mechanism is maintained at the lowest position and the cam 18 Thus, the collision noise caused by the cam follower 19 is suppressed.

In the pulp drive mechanism according to the present invention configured as described above, during normal pulp operation, the second meshing member 1
1 is in contact with the A side of the first meshing member 10, and the height of the transmission mechanism including the first and second meshing members 10, 11'ij is large (the height of the transmission mechanism is large). The body 5 performs a valve opening operation.Next, when the engine becomes lightly loaded and the control iron 15 moves downward in FIG. 3, the clamping member 14 moves to the position shown by the dashed line in FIG. and rotate the second meshing member 11 in the counterclockwise direction in FIG. 3. Then, the second meshing member 1tu,
When a pressing force is applied to the second meshing member 11 by the cam follower 19 facing the groove B of the first meshing part, the second meshing member enters into the groove B as shown in FIG. 2, and the cam follower 19 The driving force caused by this is no longer directly transmitted to the valve body 5, and the pulp is in a state of rest.

At this time, the side surface of the first meshing member 10 is pressed against the side surface C of the groove B due to the biasing force of the springs 17α, +76, and the second meshing member 11 is pressed against the side surface C in response to the swinging of the cam follower 19. The load of the return spring 13, which reciprocates with the cam follower 19 by the return spring 13 up to 0, is such that the second meshing member 11 and the cam follower 19 do not separate from each other, and is sufficiently smaller than the load of the pulp spring 9. Choose as you like. Therefore, even if a drive is applied to the second meshing member 11, it is absorbed by the return spring 13 and the valve body 5 is not driven and is in a resting state.

At this time, the hydraulic pressure supply path 24 is blocked by the control valve 25, the piston plunger 21 is maintained at the lowest point, and collision between the cam 18 and the cam follower 19 is suppressed, thereby suppressing noise.

Next, when the engine rotational speed increases, the control iron 15 moves upward in FIG. The second meshing member 11 is the surface A of the first meshing member IO.
After returning to the position where it contacts the pulp, the pulp is in a normal operating state.

According to the above-mentioned pulp drive device according to the present invention, a special transmission mechanism is disposed between the valve body of the on-off valve and the cam follower, and other parts have the same structure as before. This is preferable because the pulp suspension function can be provided with only a slight design change compared to the conventional technology. In addition, a lash adjuster is used, and although the pulp suspension and tappet clearance automatic adjustment ζ can be performed at the same time, the structure is simple, and when the pulp is suspended,
The hydraulic pressure supply path to the lash adjuster is blocked, suppressing the hammering noise caused by the collision between the cam and cam follower, and improving the durability of the valve train.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of a pulp driving device according to the present invention, FIG. 3 is a plan view of the device shown in FIG. 1, and FIG.
FIG. 3 is an exploded perspective view of the transmission mechanism in the illustrated device. Explanation of symbols of main parts l...Cylinder block 2...Intake or exhaust passage 3...Combustion chamber 4...Opening/closing valve 5...
・Valve body 10, 11...First and second meshing member 18...Cam 19...Cam follower 21...Piston plunger 25...Control valve applicant Honda Motor Co., Ltd. agent Patent attorney Fuji Muramotohiko

Claims (1)

[Scope of Claims] ('i) A cam that rotates in accordance with the rotation of the crankshaft of an internal combustion engine, a cam follower that responds to the cam and drives an on-off valve of the internal combustion engine at one end thereof, and the other end of the cam follower. a transmission mechanism that is interposed between the on-off valve and one end of the cam follower and that transmits the swinging motion of the one end of the cam follower to the valve body of the on-off valve; The mechanism is configured such that its height changes depending on the operating condition of the internal combustion engine to stop the valve body from opening, so that the rocking motion of the cam follower can be selectively transmitted to the valve body of the opening/closing valve. 1. A pulp driving device according to the present invention, wherein the pivot mechanism includes a lash adjuster, and a hydraulic pressure supply path to the lash adjuster is cut off during an opening/closing operation of the valve body. (2) The transmission mechanism is a pair of meshing members that mesh with each other and can take first and second relative angular positions about the central axis of the valve body of the on-off valve, and the meshing members are the meshing members that mesh with each other. The meshing members are configured to mesh with each other by compressive force in the central axis force direction only when they are in a second relative angular position, and include an elastic member that applies a force that causes the meshing members to separate from each other; and a positioning rod that positions the meshing member at either one of the first and second relative angular positions according to the positioning rod, and is configured to selectively shut off the hydraulic pressure supply path by the positioning rod. Claim 1 characterized in that
The pulp drive device described in Section 1.