Friction Damper Device for a Washing Machine

Abstract

A washing machine contains a friction damper device for a washing unit comprising a tub, a washing drum which is rotationally mounted in the tub and a drive for the washing drum. The washing unit is supported in an elastic manner by at least one damper counter to a lower frame part of the housing. In order to prevent the vibratory behavior of the oscillating unit from being influenced above the rotational speed of the resonance, the friction in the damper above the rotational speed of the resonance can be reduced. As a result, at least one friction covering which interacts directly on a piston rod of the damper is pretensed by an energy store counter to the piston rod and can be displaced away from the piston rod by activating an actuator.

1 - 21 . (canceled) 
     
     
         22 . A friction damper device for a washing machine in whose housing is arranged a washing unit with a tub, a washing drum rotationally mounted in the tub and a drive for the washing drum, wherein the washing unit is supported by at least one damper having a piston rod in an elastic manner against a lower frame part of the housing, wherein at least one friction lining acting directly on the piston rod of the damper is provided which is pretensed counter to the piston rod by an energy store and can be displaced away from the piston rod by activating an actuator. 
     
     
         23 . The friction damper device according to  claim 22 , wherein a slide running in the direction of the piston rod of the damper is provided which has, on its side facing the piston rod, a friction lining which is pretensed by an energy store counter to the piston rod, and in that the slide is displaceable when an electromagnetic actuator is energized, so that the friction lining is moved away from the piston rod. 
     
     
         24 . The friction damper device according to  claim 23 , wherein the friction lining is fastened to a shoulder part arranged on the side of slide facing piston rod. 
     
     
         25 . The friction damper device according to  claim 23 , wherein the slide runs perpendicularly to a longitudinal axis of the piston rod. 
     
     
         26 . The friction damper device according to  claim 23 , wherein the energy store includes a compression spring. 
     
     
         27 . The friction damper device according to  claim 23 , wherein the energy store includes a compression spring in the form of a helical spring surrounding a partial region of the slide whose one end bears against the shoulder part and whose other end bears against a stop part, in that the region of the slide facing away from the shoulder part is guided through an opening in the stop part and can be attracted by an electromagnet of the actuator for moving the slide. 
     
     
         28 . The friction damper device according to  claim 27 , wherein the actuator is arranged in a housing part whose end face facing the piston rod forms the stop part. 
     
     
         29 . The friction damper device according to  claim 28 , wherein the housing part is fastened to a region of a second housing part running transversely to the piston rod, which region surrounds the shoulder part with the friction lining, the tension spring and a partial region of the slide, and in that a second region of the second housing part runs in the direction of the longitudinal extension of the piston rod, surrounds it and is connected to the region of the housing running transversely to the piston rod, wherein the piston rod is guided outwards through an opening of the second region of the second housing part. 
     
     
         30 . The friction damper device according to  claim 23 , further comprising a second friction lining fixedly arranged on the side of the piston rod opposite the friction lining so that the piston rod is retained in a damping manner between the friction lining and the second friction lining by the force of the compression spring when the actuator is energized. 
     
     
         31 . The friction damper device according to  claim 23 , wherein the friction lining is provided on its side facing the piston rod with an annular friction surface which is able to bear against a partial region of the peripheral surface of the piston rod. 
     
     
         32 . The friction damper device according to  claim 30 , wherein the second friction lining is provided on its side facing the piston rod with a second annular friction surface which is able to bear against a partial area of the peripheral surface of the piston rod. 
     
     
         33 . The friction damper device according to  claim 32 , wherein the second friction lining is fastened on its side facing away from the piston rod to an inner wall of the second housing part running in a circular course. 
     
     
         34 . The friction damper device according to  claim 23 , wherein the electromagnetic actuator actuates the slide so that when the actor is energized, the friction lining releases the piston rod and in that when the actuator is de-energized the friction lining is pressed against the piston rod. 
     
     
         35 . The friction damper device according to  claim 23 , wherein a control unit is provided by means of which the electromagnetic actuator can be energized so that the compression force exerted by the energy store on the piston rod through the friction lining is compensated for according to the predetermined damping profile. 
     
     
         36 . The friction damper device according to  claim 22 , wherein the friction lining is fastened to a support part which is arranged on the periphery of a piston arranged in a cylinder of the damper and connected to the piston rod, and is pretensed by the energy store counter to the inner wall of the cylinder, and in that the actuator, when activated, displaces the support part and the friction lining away from the inner wall of the cylinder against the pretension of the energy store. 
     
     
         37 . The friction damper device according to  claim 36 , wherein the actuator is a memory metal part arranged on the piston, which part, when energized mechanically, generates the force that moves the friction lining away from the inner wall. 
     
     
         38 . The friction damper device according to  claim 36 , wherein the energy store has a recuperating spring that pretenses the support part and the friction lining to the inner wall of the cylinder. 
     
     
         39 . The friction damper device according to  claim 36 , wherein a second friction lining is provided which is connected to the friction lining so that it rotates about a fulcrum, in that the friction lining and the second friction lining run at least partially around the periphery of the piston, and engages on its side facing the piston in a peripheral groove of the same, in that the memory metal part acts on the support part and a second support part, and in that the end regions of the support part and the second support part facing away from the fulcrum are spread apart by the recuperating spring. 
     
     
         40 . The friction damper device according to  claim 39 , wherein the memory metal part is a rod-shaped part running through a through opening running transversely through the piston, which part is fastened with one end to the support part and with the other end to the second support part. 
     
     
         41 . The friction damper device according to  claim 40 , wherein the memory metal part is formed by a metal wire. 
     
     
         42 . The friction damper device according to  claim 39 , wherein the memory metal part takes the form of a memory wire which is formed into a loop and, when energized, reduces the circumference of the loop, and in that the loop runs around a roll arranged in the piston and fastened to the support part, and is fastened on the side opposite the roll to the second support part. 
     
     
         43 . A washing machine comprising:
 a housing having a frame;   a washing unit disposed within the housing and including a tub, a washing drum rotationally mounted in the tub and a drive for rotating the washing drum,   a damper least partially supporting the washing unit and having a piston rod in an elastic manner against the frame of the housing,   a friction lining acting directly on the piston rod of the damper and being pretensed to counter to the piston rod by an energy store and being displacable in a direction away from the piston rod in response to activation of an actuator.