SU1401187A1 - Liquid damper - Google Patents

Abstract

The invention relates to mechanical engineering, namely to means for damping vibrations. The purpose of the invention is to increase the damping efficiency by automatically changing the amount of damping as the load changes. When moving the pistons 4 and 6 of the hydraulic damper, the working fluid flows through the throttle openings 9 and the oscillation energy is quenched. 1 il.

Description

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The invention relates to mechanical engineering, namely to means for damping vibrations.

The purpose of the invention is to increase the efficiency of damping by automatically changing the amount of damping as the load changes.

The drawing shows a hydraulic damper, longitudinal section.

The hydraulic damper contains; case 1 with a lid 2, inside of which: Go is placed the rod 3 with the piston 4, connected in series with it through the elastic elements 5 floating, the pistons 6 in which the throat holes 7 are made, coaxially 1 cup 8 disposed in the body with throttle openings 9 of different diameters along the cup height. All pistons in the beaker have 10 x longitudinal travel restraints to prevent the closure of the choke holes of the beaker.

Hydraulic damper works as follows.

When vibrations are perceived, the rod 3 displaces the first of the pistons 4 and through; Spring elements 5 - after-stroke floating pistons 6 in a cylindrical gtakk 8, causing the working fluid to directly flow from rod 3 at the same time from the molds 11, formed by jibix in the cup 8 by adjacent pistons, k also the last of the pistons and the bottom of the Cup, through the throttle holes 9 of different diameters, made to the walls of the glass 8, into the chamber 12 11 between the glass and the body 1, and with (}) the fraternal course of the rod 3 - from the chamber 12 f of the cavity 11.

; At low oscillation frequencies and, (successively, low displacement speeds of the stem 3, the working fluid is relatively free to flow through throttle openings that have large flow areas and there is little energy dissipation. At the same time, much of the energy dissipates the flow of fluid through the throttle holes of small diameter.

At high frequencies, the oscillations perceived by the damper, due to the large resistance to the flow of fluid through the throttle openings, small in diameter, bounding the cavities with such openings, are displaced almost as a whole, and

damping is carried out due to the flow of fluid through the throttle holes with large flow areas. Using a cup with a set of choke holes, each group of which effectively operates in a certain frequency range, and a moving element with a corresponding number of pistons, one can obtain the desired damping characteristic of the damper in a wide frequency range. The speed and reliability of the damper are due to the simultaneous flow of fluid through all the orifices.

When selecting the gap between the stops 10 and the adjacent piston, the corresponding orifices are turned off from work, which also expands the possibilities of obtaining the required damper characteristic when running stops of various lengths.

Due to the selection of the lengths of the stops 10, the throttle holes 7 within the stroke of the movable element do not overlap the pistons 4.

Adjusting the damper to work in different frequency ranges is carried out by replacing the movable element and the cup 8 with throttle holes 9, disconnecting them from the rod 3 and the housing 1, respectively. At the same time, to ensure efficient operation of the damper at the resonant frequencies of the protected mechanical system, the number of pistons of the movable element is chosen to be equal to the number of peaks of the amplitude-frequency characteristic of the system (the number of elastic-related masses). The same number of groups of choke holes (the holes of each group — two in the drawing — have the same bore diameter) has a cup 8, and the ratio of the diameters of the choke holes of different groups is determined by the formula

.with

50

DI J i2J Dj Ifcj-m;

where (L ,, n);

I) - diameter of the throttle hole;

m is the mass or moment of inertia of one of the bodies of the system;

c is the stiffness of the corresponding elastic element;

n is the number of pistons.

1401187

Claims (1)

Formula of invention Hydraulic damper, containing-, no damping efficiency, he. housing with a lid, inside which is provided with a coaxially located A piston is placed in the go, afterwards in a housing with a throttle body, connected with it through elbows of different diameters along the high elements floating pistons, in which glass are placed; only in the last runes are mostly executed and have limiters Saline holes, features longitudinal movement.