Direct-drive connecting rod mechanism for electric backrest of sofa

The invention provides a sofa electric backrest direct-drive connecting rod mechanism which comprises a sofa framework and a backrest mechanism, sliding block devices are arranged on the left side and the right side of the sofa framework, the backrest mechanism is fixedly connected with one end of the sofa framework, and the backrest mechanism comprises a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod and a motor. A rotating shaft of the motor is fixedly connected with the first connecting rod, the middle of the first connecting rod is rotationally connected with the second connecting rod and the fourth connecting rod, the other end of the second connecting rod is rotationally connected with the third connecting rod, the tail end of the third connecting rod is rotationally connected with the middle of the fourth connecting rod, and the tail end of the first connecting rod is rotationally connected with the sliding block device. The fourth connecting rod is fixed