CS201262B1 - Vibration absorber of the distribution mechanism - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damper for a piston machine, in particular an internal combustion engine.

In the operation of the timing mechanism, there is an oscillation which causes, in particular at higher machine speeds, to exceed a certain limit given by the restoring force of the springs, which results in a break in the force contact between the individual members of the mechanism, manifested by the bounce. At the moment of reconnection, shock events occur, lasting for a very short time and therefore causing high stresses. Impacts cause excessive noise and wear. As is well known, the lines of most modern high-speed machines normally work with bouncing at higher speeds. The usual oscillation limitation by designing a favorable cam stroke curve is only partially successful because it is highly dependent on manufacturing accuracy. The efficiency of these methods also decreases due to uneven wear of the cams. A limited increase in the spring force is prevented by the limited space for their installation.

These drawbacks are solved by a shock absorber according to the invention, consisting of a resilient oscillating and damped inertial mass, and the principle is that the inertial mass is connected to the rocker arm of the valve by at least one connecting member which is a combination of at least one spring element and at least one element. attenuating.

The inertia mass limits the oscillation of the timing mechanism according to the arrangement either by a rotational oscillating movement about the axis of the rocker arm opening or by a rocking movement on a lever mounted on the rocker arm.

This arrangement does not interfere with the timing operation and is effective over the entire engine speed range. The damper function is independent of cam wear or imprecise design.

In the accompanying drawing, there is shown an exemplary embodiment of a vibration damper according to the invention, wherein FIG. 1 shows a damper limiting the rocker oscillations by rotary oscillating motion about the rocker arm axis; FIGS. Fig. 4 is a diagram of the inertial force over time without and with the use of a damper and the course of spring force.

Giant. 1 shows the connection of inertial mass 1 to the rocker arm 7 by means of spring elements 2 and damping elements 3. In the example shown, a rubber having both of these properties is used for both the cushioning and cushioning, i.e. it comprises an infinite number of cushioning and cushioning elements that form an integral connecting member.

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Giant. 2 shows an example of the connection of the inertia mass 1 to the rocker arm 7 by a spring-loaded lever element 2 which forms a ring inside the valve rocker hole 7 interconnected with the valve rocker body 7 by at least one damping element 3.

Giant. 3 shows an example of the connection of the inertia mass 1 to the rocker arm 7 by a spring-loaded lever element 2, wherein the damping element 3 is arranged to act on the lever formed by the spring-loaded element 2 and thus limits its oscillations.

In Fig. 4, where F denotes the coordinate axis of the force and t the coordinate axis of time, the time course of the inertia force 4 without the damper is shown in solid line and the course of the inertia force 5 using the dotted damper. In the lower part of this figure, part of the course of the spring force 6 is plotted. These graphs show that the application of the damper does not intersect the line of the inertia force 5 and the curve of the spring force 6, thus no harmful rebound occurs.

Claims (1)

A vibration damper for a piston machine, in particular an internal combustion engine, comprising a resiliently attached oscillating and damped inertial mass, characterized in that the inertial mass (1) is connected to the rocker arm (7) by at least one connecting member which is a combination of at least one a spring element (2) and at least one damping element (3).