Damping arrangement
AssigneeStabilus GmbH
InventorHans Pohlenz
Life of this patent
Estimating the term…
Abstract
A damping arrangement for the tub assembly of a washing machine and the like in which a piston mounted on a piston rod in the cavity of a cylinder axially separates two compartments of the cavity and is formed with restricted throttling passages connecting the compartments. The piston may be by-passed by a bore in the piston rod having respective orifices in the two compartments, one orifice being capable of being blocked by an inert mass mounted on the piston rod in one of the compartments for oscillation at the end of a spring. Movement of the inert mass away from a rest position toward which it is normally biased by the spring is limited by a secondary hydraulic damper to prevent operating noise and reduce premature wear.
Claims10
A damping arrangement comprising:
- (a) a cylinder member having an axis and bounding a cavity therein;
- (b) a piston rod sealingly engaging said cylinder member for axial movement inward and outward of said cavity;
- (c) a liquid in said cavity;
- (d) a piston member mounted on said piston rod in said cavity and axially defining two compartments of said cavity,
- (1) said piston member being formed with at least one throttling passage for restricted flow of said liquid between said compartments,
- (2) said piston rod being formed with a bore having respective orifices in said compartments for by-passing said piston member,
- (e) an inert mass mounted on said piston rod for axial movement in one of said compartments between two axially terminal positions;
- (f) blocking means movable in said cavity toward and away from a blocking position in which said blocking means impedes flow of said liquid through one of said orifices, said blocking means constituting a portion of said inert mass and said blocking means being moved toward and away from said blocking position in response to said axial movement of said mass;
- (g) a spring interposed between said mass and said piston rod for biasing said mass toward a pre-determined axial position spacedly intermediate said terminal positions, ;
- and
- (h) hydraulic damping means for damping axial movement of said mass in a direction away from said intermediate position and toward both of said terminal positions to prevent contact with said piston and the end wall of said cylinder member in said compartment, said damping means comprising first damping elements on said inert mass and a second damping element on each of said piston and end wall in said one compartment, one of said first and second elements bounding a receptacle open axially toward the other element, the other element being dimensioned to be received in said receptacle during axial movement of said mass.
Dependencies are inferred from the claim text.