Damper for washing machine

Abstract

Disclosed is a damper for a washing machine, the damper including an external electric source, a movable part for adjusting damping force using the external electric source, a damping pad for varying an exerting state of the damping force in response to an operation of the movable part, a pad holder for supporting the damping pad, a cylinder contacting the damping pad to generate the damping force, a rod inserted in the cylinder. The cylinder is connected to one of a movable part and case of the washing machine, and the rod is connected to the other of the movable part and case of the washing machine. The pad holder is disposed on an outer circumference of the rod.

What is claimed is:  
     
         1 . A damper for a washing machine, comprising: 
 an external electric source;    a movable part for adjusting damping force using the external electric source;    a damping pad for varying an exerting state of the damping force in response to an operation of the movable part;    a pad holder for supporting the damping pad;    a cylinder contacting the damping pad to generate the damping force, the cylinder being connected to one of a movable part and case of the washing machine; and    a rod inserted in the cylinder and connected to the other of the movable part and case of the washing machine, the pad holder being disposed on an outer circumference of the rod.    
     
     
         2 . The damper according to  claim 1 , wherein the movable part comprises: 
 an electromagnet formed on a predetermined location of the rod and selectively magnetized; and    a magnetic member formed on the pad holder, the magnetic member moving by the electromagnet.    
     
     
         3 . The damper according to  claim 1 , wherein the movable part comprises: 
 a thermal expanding member formed on a predetermined location of the rod; and    a sliding rod connected to an expanding end of the thermal expanding member, the sliding rod being provided with a stopper end selectively contacting the pad holder.    
     
     
         4 . The damper according to  claim 1 , wherein the movable part comprises: 
 a heater formed on a predetermined location of the rod and heated by the external electric power; and    a thermal expanding member expanding by the heat transmitted from the heat to compressing the pad holder.    
     
     
         5 . The damper according to  claim 4 , wherein a fixing bar is disposed between the thermal expanding member and the pad holder to transmit expanding force.  
     
     
         6 . The damper according to  claim 1 , wherein the movable part is designed to generate heat, a magnetic field, or a shape variation by the external electric source.  
     
     
         7 . A damper for a washing machine, comprising: 
 an external electric source;    an electromagnet for selectively generating an magnetic field by the external electric source;    a pad holder for fixing a magnetic member operated by the magnetic field;    a damping pad supported on the pad holder;    a cylinder contacting the damping pad to generate the damping force, the cylinder being connected to one of a movable part and case of the washing machine; and    a rod for fixing the electromagnet, the rod being inserted in the cylinder and connected to the other of the movable part and case of the washing machine, the pad holder being disposed on an outer circumference of the rod.    
     
     
         8 . The damper of  claim 7 , wherein the magnetic member is protruded toward the electromagnet.  
     
     
         9 . The damper of  claim 7 , wherein the magnetic member is fixed on a protruded portion formed on the pad holder and protruded toward the electromagnet.  
     
     
         10 . The damper of  claim 7 , wherein the magnetic member comprises a plurality of a circular arc-shaped members that are spaced from each other at a predetermined distance.  
     
     
         11 . The damper of  claim 7 , wherein the rod is provided with a guide groove for receiving the magnetic member.  
     
     
         12 . The damper of  claim 7 , wherein the rod is provided at an outer circumference with a second damping pad contacting the inner circumference of the cylinder.  
     
     
         13 . The damper of  claim 7 , wherein the pad holder is provided at both sides with elastic members.  
     
     
         14 . The damper of  claim 13 , wherein the elastic member is a spring.  
     
     
         15 . The damper of  claim 13 , wherein the elastic member is a sponge.  
     
     
         16 . A damper for a washing machine, comprising: 
 an external electric source;    a thermal expanding member selectively expanding by the external electric source;    a sliding rod displacing by the thermal expanding member;    a pad holder disposed around an outer circumference of the sliding rod;    a damping pad supported on the pad holder;    a cylinder contacting the damping pad to generate the damping force, the cylinder being connected to one of a movable part and case of the washing machine; and    a rod connected to the sliding rode, inserted in the cylinder, and connected to the other of the movable part and case of the washing machine.    
     
     
         17 . The damper of  claim 16 , wherein the pad holder is disposed between an inserted end of the sliding rod and an inserted end of the rod.  
     
     
         18 . A damper for a washing machine, comprising: 
 an external electric source;    a thermal expanding member selectively expanding by the external electric source;    a pad holder compressed by the thermal expanding member;    a damping pad formed on an outer circumference of the pad holder;    a cylinder contacting the damping pad to generate the damping force, the cylinder being connected to one of a movable part and case of the washing machine; and    a rod connected to the sliding rode, inserted in the cylinder, and connected to the other of the movable part and case of the washing machine.    
     
     
         19 . The damper of  claim 18 , wherein the pad holder is formed in a circular arc-shape to expand and contract in a radial direction.  
     
     
         20 . The damper of  claim 18 , wherein a fixing rod is disposed between the pad holder and the thermal expanding member.  
     
     
         21 . A damper for a washing machine, comprising: 
 a stationary case disposed in the washing machine;    a movable part disposed in the washing machine;    a cylinder connected to one of the stationary case and the movable part;    a rod inserted in the cylinder, the rod being connected to the other of the stationary case and the movable part;    a damping pad contacting an inner circumference of the cylinder to selectively perform damping;    a pad holder for supporting the damping pad; and    a movable part for adjusting a state of the pad holder using the external electric source.