Laundry machine

Abstract

The patent application relates to a laundry machine comprising a drum in which laundry is to be placed, a drive assembly including a shaft ( 351 ) connected to the drum, a bearing housing ( 400 ) to rotatably support the shaft ( 351 ), a motor to rotate the shaft ( 351 ), and a suspension assembly to reduce vibration of the drum. The suspension assembly further includes at least two suspension units which are arranged one in front of the other and the front unit of which is located before a weight center of an assembly of the drum and the drive assembly.

1 . A laundry machine comprising:
 a drum in which laundry is to be placed;   a drive assembly including a shaft connected to the drum, a bearing housing to rotatably support the shaft, and a motor to rotate the shaft;   a suspension assembly to reduce vibration of the drum, the suspension assembly including at least 2 suspension units which are arranged one in front of the other and the front unit of which is located before a weight center of an assembly of the drum and the drive assembly.   
     
     
         2 . The laundry machine as claimed in  claim 1 , wherein the other suspension unit is located behind the weight center. 
     
     
         3 . The laundry machine as claimed in  claim 2 , wherein the front unit includes 2 spring dampers and the rear unit include only one spring damper. 
     
     
         4 . The laundry machine as claimed in  claim 2 , wherein a net spring constant of the front unit is different from a net spring constant of the rear unit. 
     
     
         5 . The laundry machine as claimed in  claim 4 , wherein the front net spring constant is greater than the rear net spring constant. 
     
     
         6 . The laundry machine as claimed in  claim 5 , wherein the front net spring constant is equal to or greater than twice of the rear net spring constant. 
     
     
         7 . The laundry machine as claimed in  claim 6 , wherein the front net spring constant is eaqual to or greater than 14000N/m and the rear net spring constant is eaqual to or smaller than 6000N/m. 
     
     
         8 . The laundry machine as claimed in  claim 5 , further comprising:
 a tub to hold water therein;   a flexible material to prevent the water inside the tub from leaking toward the drive assembly and allow the drive assembly to move relatively to the tub, the flexible material having a spring constant of 8000N/m or smaller with respect to a displacement of the drive assembly in an up-and-down direction.   
     
     
         9 . The laundry machine as claimed in  claim 5 , wherein a net damping factor of the front suspension unit is greater than a net damping factor of the rear suspension unit. 
     
     
         10 . The laundry machine as claimed in  claim 9 , wherein a total damping factor of the suspension assembly is equal to or smaller than 340 N/mm. 
     
     
         11 . The laundry machine as claimed in  claim 5 , wherein the front suspension unit has more suspensions than the rear suspension unit. 
     
     
         12 . The laundry machine as claimed in  claim 5 , wherein the front suspension unit includes 2 suspensions arranged left and right sides with respect to a rotational axis of the drum, and the rear suspension unit includes one suspension arranged offset from the middle of the 2 suspensions along the rotational axis. 
     
     
         13 . The laundry machine as claimed in  claim 12 , wherein the 3 suspensions are spring dampers. 
     
     
         14 . The laundry machine as claimed in  claim 12 , wherein respective spring constants of the front  2  suspensions are greater than a spring constant of the rear suspension. 
     
     
         15 . The laundry machine as claimed in  claim 12 , wherein the front 2 suspensions are arranged symmetrically with respect to the rotational axis. 
     
     
         16 . The laundry machine as claimed in  claim 12 , wherein the respective spring constants of the front 2 suspensions are 7000˜8600N/m, and the spring constant of the rear suspension is 4500˜5500 N/m. 
     
     
         17 . The laundry machine as claimed in  claim 16 , further comprising:
 a tub to hold water therein;   a flexible material to prevent the water inside the tub from leaking toward the drive assembly and allow the drive assembly to move relatively to the tub, the flexible material having a spring constant of 6000 N/m or smaller with respect to a displacement of the drive assembly in an up-and-down direction.   
     
     
         18 . The laundry machine as claimed in  claim 16 , wherein respective damping factors of the 3 suspensions are 35˜45N/mm. 
     
     
         19 . The laundry machine as claimed in  claim 18 , wherein the suspension assembly further comprises a damping unit exerting 70˜90 N/mm in total. 
     
     
         20 . The laundry machine as claimed in  claim 19 , wherein the damping unit includes 2 non-spring dampers arranged left and right sides with respect to the rotational axis of the drum. 
     
     
         21 . The laundry machine as claimed in  claim 1 , wherein the suspension assembly has a net spiring constant of 17820˜21780 N/m with respect to a displacement of the drum in an up-and-down direction. 
     
     
         22 . The laundry machine as claimed in  claim 1 , wherein the suspension assembly has a net damping factor of 180˜220 N/mm. 
     
     
         23 . The laundry machine as claimed in  claim 1 , wherein the rear suspension unit is compressed more than the front suspension unit is when they are initially installed. 
     
     
         24 . The laundry machine as claimed in  claim 1 , wherein the suspension assembly is attached to the bearing housing. 
     
     
         25 . The laundry machine as claimed in  claim 1 , further comprising:
 a flexible material to prevent the water inside the tub from leaking toward the drive assembly and allow the drive assembly to move relatively to the tub.   
     
     
         26 . The laundry machine as claimed in  claim 1 , wherein the tub is supported more rigidly than the drum is.