Mechanical extension device of rocking seat

A mechanical extension device for a rocking chair, comprising:

• a base, a first swinging rod, a second swinging rod, an actuator, and two mechanical extension units arranged in a bilateral symmetry,
• wherein the first swinging rod and the second swinging rod are connected to the base, the two mechanical extension units are connected to the first swinging rod and the second swinging rod in a rotating mode, and the first swinging rod and the second swinging rod are configured to swing the two mechanical extension units on the base;
• the actuator is arranged between the two mechanical extension units and drives the two mechanical extension units to act;
• each of the two mechanical extension units comprises a linkage rod, a seat connector, a backrest connector, a footrest, a leg rest connecting rod assembly, a first connecting rod, and a second connecting rod, the footrest is installed on the leg rest connecting rod assembly, the leg rest connecting rod assembly is configured to extend under an action of the actuator and control the footrest to fold or extend, the leg rest connecting rod assembly is arranged at a front end part of the seat connector, and the backrest connector is arranged at a rear end part of the seat connector, the first connecting rod is rotationally connected to the first swinging rod, and the second connecting rod is rotationally connected to the second swinging rod, two ends of the linkage rod are respectively in a rotary connection to the leg rest connecting rod assembly and the second connecting rod;
• the actuator is respectively connected to the seat connector and the leg rest connecting rod assembly in a rotating way and drives the seat connector and the leg rest connecting rod assembly to move relatively;
• a locking device is arranged on the second connecting rod, a guide groove with an open side is formed in the base, and a locking groove is formed in a path end point of the guide groove;
• the rocking chair is provided with a sitting posture state for a human body to sit and a lying posture state for the human body to lie, and the leg rest connecting rod assembly is folded in front of the seat connector in the sitting posture state;
• when the sitting posture state is switched to the lying posture state, the leg rest connecting rod assembly is driven by the actuator to extend and the linkage rod drives the second connecting rod to move, the second connecting rod drives the backrest connector to tilt backwards, meanwhile, the locking device enters the guide groove from the open side of the guide groove and is guided to the locking groove by the guide groove, the two mechanical extension units and the base are locked to swing relatively, and the lying posture state is switched.