JPH07648Y2 - Engine valve clearance adjustment device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for adjusting a valve clearance of an automobile engine by a mechanical mechanism.

2. Description of the Related Art Problems to be Solved by Conventional Techniques and Inventions Conventionally, as one of valve clearance adjusting devices for an engine, the valve clearance is adjusted by using the pressure of hydraulic oil attached to a cylinder head of the engine. However, in such a hydraulic type adjusting device, not only the adjusting function greatly changes depending on the amount of air mixed in the hydraulic oil, but also the passage of the hydraulic oil is changed. Since it has to be provided inside the cylinder head, the molding of the cylinder head is complicated and the manufacturing cost is high.

Means for Solving the Problems As a means for solving the above problems, the present invention provides a sliding body fitted to a main body so as to be freely slidable and non-rotatable.
The first spring biases the main body in a direction away from the main body so that a gap is formed between the main body and the main body, and the sliding body is screwed in the axial direction by rotation about an axis parallel to the sliding direction. A rotating body is screwed onto the main body, and a second spring is stored between the rotating body and the main body, in which an elastic restoring force is accumulated along with the rotation of the rotating body in the direction of screwing while approaching the main body. It is configured to be attached.

Advantageous Effects and Advantages of the Invention The present invention is configured as described above, and cams one of the main body and the rotary body while the elastic restoring force is stored in the second spring by screwing the rotary body in the approaching direction to the main body. Or to the rocker arm linked to the cam, the other to the valve stem,
When mounted by abutting, the sliding body is separated from the main body by the urging force of the first spring, and is also separated from the main body of the rotating body by being sandwiched between the cam or the rocker arm and the valve stem. Of the second spring is elastically restored when the distance between the cam or locker arm and the valve stem is larger than a predetermined distance and the valve clearance is widened. By rotating the rotating body by force and screwing it in the direction away from the main body, the valve clearance is adjusted to be narrowed to 0, and the distance between the cam or locker arm and the valve stem is smaller than the predetermined distance. When it is also narrowed, the rotating body and the sliding body are united by being pinched between them, and the book is resisted against the elastic force of the first spring. To the valve stem, thereby avoiding interference between the cam or locker arm and the valve stem, and adjusting the valve clearance by a mechanical mechanism rather than hydraulically. Since there is no need to form a passage for hydraulic oil in the cylinder head, unlike the conventional device, the manufacturing cost of the cylinder head does not increase, and air mixed in the hydraulic oil is not used. Since there is no significant change in the adjusting function depending on the amount of, there is an effect that stable operation can be performed.

Embodiment Hereinafter, one embodiment of the present invention will be described with reference to FIG.

The adjusting device of the present embodiment is interposed between a cam a and a valve stem b protruding downward from a cam (not shown), and is a cylindrical main body 1 having an open bottom surface. However, the upper end surface of the main body 1 is made to correspond to the outer peripheral surface of the cam a, and the outer peripheral surface is tightly and slidably fitted into the circular guide hole B formed in the cylinder head A. On the lower surface in the hollow, a cylindrical sleeve 2 having a flange-shaped stopper 3 projecting from the outer periphery of the lower end is fixed concentrically by press-fitting the upper end thereof and non-rotatably around the axis. The sleeve 2 has a ring-shaped slide body 5, and the spline groove 6 formed on the inner periphery of the slide body 5 is closely fitted to the spline strip 7 formed on the outer periphery of the sleeve 2 so that the slide body 5 can freely slide in the axial direction. And is fitted so that it cannot rotate around the axis. There are, between the lower surface of the upper surface and the main body 1 of the slider 5, the disc spring 10 for biasing the sliding body 5 in the direction away from the main body 1 is attached.

Further, the sliding body 5 has a cylindrical shape with an open upper surface,
The rotating body 12 whose lower surface is curved so as to bulge downward is screwed with the female screw 13 formed on the inner periphery thereof to the male screw 14 formed on the outer periphery of the sliding body 5 to achieve concentric and smooth rotation. It is freely mounted along with the axial movement along with it,
Between this rotating body 12 and the main body 1, a coil spring 15 concentrically housed in the hollow of the sleeve 2 has bent portions 15a, 15a at both upper and lower ends thereof, respectively, on the lower surface of the main body 1 and the rotating body 12. It is mounted by being fixed to the upper surface of and by being hooked to the hooking portions 16, 16.

In the adjusting device having the above-described configuration, the rotating body 12 is rotated with respect to the main body 1 and the sliding body 5 and screwed in the direction of approaching the main body 1, and the elastic restoring force is stored in the coil spring 15, The upper surface of the main body 1 is brought into contact with the outer peripheral surface of the cam a, and the center of the curved lower surface of the rotating body 12 is brought into contact with the center of the upper end surface of the valve stem b biased upward by the compression coil spring c. Therefore, in a state where the outer peripheral surface of the cam a and the upper end surface of the valve stem b are kept at a predetermined distance, the sliding body 5 is moved by the biasing force of the disc spring 10. It is separated from the lower surface of the main body 1 with a gap S abutting against the stopper 3 of the sleeve 2 and is prevented from moving in the direction away from the main body 1 by being sandwiched between the cam a and the valve stem b. The rotating body 12 It is held in a state of non-rotatable relative to the sliding body 5 and.

When the distance between the cam a and the valve stem b becomes wider than the predetermined distance, the rotating body 12 moves to the coil spring.
Due to the elastic restoring force of 15, the sliding member 5 is rotated and screwed in a direction away from the main body 1, so that there is no gap between the cam a and the main body 1, and between the valve stem b and the rotary body 12. The valve clearance is adjusted accordingly, and conversely, when the distance between the cam a and the valve stem b is narrower than a predetermined distance, the cam a and the valve stem b are pinched. Therefore, the sliding body 5 and the rotating body 12 which is prevented from rotating with respect to the sliding body 5 are integrated, and the gap S is narrowed while being guided by the sleeve 2 against the urging force of the disc spring 15. The cam a and the valve stem b are prevented from interfering with each other by moving in the direction of approaching, thereby reducing the distance between the upper surface of the main body 1 and the lower surface of the rotating body 12.

Although the adjusting device of this embodiment is arranged to be interposed between the cam a and the valve stem b, the present invention comprises a rocker arm and a valve stem b that swing together with the cam a. It can also be applied to the case of interposing between.

[Brief description of drawings]

FIG. 1 attached is a sectional view of an embodiment of the present invention. 1: Main body, 5: Sliding body, 10: Disc spring (first spring), 12: Rotating body, 13: (Rotating body) female screw, 14: (Sliding body) male screw,
15: Coil spring (second spring), S: Gap

Claims (1)

[Scope of utility model registration request] 1. A sliding body which is slidably and non-rotatably fitted to a main body is urged by a first spring in a direction away from the main body, and a gap is formed between the main body and the main body. A rotating body is screwed into the sliding body so as to be screwed in the axial direction by rotation about an axis parallel to the sliding direction, and the body of the rotating body is provided between the rotating body and the body. A valve clearance adjusting device for an engine, characterized in that a second spring for accommodating an elastic restoring force with rotation in a screwing direction while approaching the engine is mounted.