Electric Sofa Stent

Abstract

An electric sofa stent comprising two coupled assemblies, a drive link and a motor drive. When the motor drive is driving the drive link into rotation, the headrest is driven to rotate via the coupled assemblies. Each of the coupled assemblies comprises of a first connector, a second connector, a third connector, a first fixture and a headrest connector. One end of the first connector is fixedly connected to the drive link, and the other end is pivot connected to one end of the second connector. The other end of the second connector is pivot connected to one end of the third connector. The other end of the third connector is pivot connected to the first fixture, which is fixed on the side frame. The upper end of the headrest connector is fixedly connected to the headrest, and the lower end is pivot connected to the third connector.

What is claimed is: 
     
         1 . An electric sofa stent, comprising:
 two symmetrically disposed coupled assemblies ( 1 );   a drive link ( 3 ) connecting the two coupled assemblies;   a motor drive ( 2 ) capable of driving the drive link ( 3 ) into rotation;   bottom ends of the two coupled assemblies ( 1 ) fixedly connected with ends of the drive link ( 3 );   top ends of the two coupled assemblies ( 1 ) are fixedly connected with ends of a headrest ( 4 );   a first connector ( 11 ) on each coupled assembly ( 1 ), a first end of the first connector ( 11 ) fixedly connected to a corresponding end of the drive link ( 3 )   a second connector ( 12 ) on each coupled assembly ( 1 ), a second end of the first connector ( 11 ) pivot connected to a first end of the second connector ( 12 );   a third connector ( 13 ) on each coupled assembly ( 1 ), a second end of the second connector ( 12 ) pivot connected to a first end of the third connector ( 13 );   a first fixture ( 14 ) on each coupled assembly ( 1 ), a second end of the third connector ( 13 ) pivot connected to the first fixture ( 14 ), the first fixture ( 14 ) fixed on a side frame ( 5 );   a headrest connector ( 15 ) on each coupled assembly ( 1 ), an upper end of the headrest connector ( 15 ) fixedly connected to the headrest ( 4 ); a lower end of the headrest connector ( 15 ) pivot connected to the third connector ( 13 ) such that the headrest connector ( 15 ) is capable of rotating around a pivot joint of the headrest connector ( 15 ) with the third connector ( 13 );   a first limiting structure provided between the headrest connector ( 15 ) and the third connector ( 13 ) to restrict a rotation angle of the headrest connector ( 15 ) relative to the third connector ( 13 ); and   a tension spring ( 6 ) provided between the headrest connector ( 15 ) and the third connector ( 13 ), capable of providing a backward pull to the headrest connector ( 15 ), a first end of the tension spring ( 6 ) connected to the headrest connector ( 15 ), a second end of the tension spring ( 6 ) connected to the third connector ( 13 );   wherein when the motor drive ( 2 ) is driving the drive link ( 3 ) to rotate in a forward and backward direction, the headrest ( 4 ) is driven to rotate forward and backward via the coupled assemblies ( 1 ).   
     
     
         2 . The electric sofa stent according to  claim 1 , further comprising:
 a first arcuate limiting slot ( 8 ) of the first limiting structure, the first arcuate limiting slot ( 8 ) formed on the third connector ( 13 ) or on the headrest connector ( 15 ); and   a first limiting stub ( 9 ) of the first limiting structure, the first limiting stub ( 9 ) fixed on the headrest connector ( 15 ) or on the third connector ( 13 ), the first limiting stub ( 9 ) mating with the first arcuate limiting slot ( 8 );   wherein when the headrest connector ( 15 ) rotates relative to the third connector ( 13 ), the first limiting stub ( 9 ) moves in the first arcuate limiting slot ( 8 ).   
     
     
         3 . The electric sofa stent according to  claim 1 , further comprising:
 a second limiting structure provided on the side frame ( 5 ) to restrict a rotation angle of the first connector ( 11 ).   
     
     
         4 . The electric sofa stent according to  claim 3 , further comprising:
 a second fixture ( 7 ) of the second limiting structure, the second fixture ( 7 ) fixed on an inner side of the side frame ( 5 );   a second arcuate limiting slot ( 10 ) formed on the second fixture ( 7 ) or on the first connector ( 11 ); and   a second limiting stub ( 101 ) of the second limiting structure, the second limiting stub ( 101 ) fixed on the first connector ( 11 ) or on the second fixture ( 7 ), the second limiting stub ( 101 ) mating with the second arcuate limiting slot ( 10 );   wherein when the second connector ( 12 ) rotates relative to the second fixture ( 7 ), the second limiting stub ( 101 ) moves in the second arcuate limiting slot ( 10 ).   
     
     
         5 . The electric sofa stent according to  claim 2 , further comprising:
 a second limiting structure provided on the side frame ( 5 ) to restrict a rotation angle of the first connector ( 11 ).   
     
     
         6 . The electric sofa stent according to  claim 6 , further comprising:
 a second fixture ( 7 ) of the second limiting structure, the second fixture ( 7 ) fixed on an inner side of the side frame ( 5 );   a second arcuate limiting slot ( 10 ) formed on the second fixture ( 7 ) or on the first connector ( 11 ); and   a second limiting stub ( 101 ) of the second limiting structure, the second limiting stub ( 101 ) fixed on the first connector ( 11 ) or on the second fixture ( 7 ), the second limiting stub ( 101 ) mating with the second arcuate limiting slot ( 10 );   wherein when the second connector ( 12 ) rotates relative to the second fixture ( 7 ), the second limiting stub ( 101 ) moves in the second arcuate limiting slot ( 10 ).