Underframe with improved structure

An underframe with an improved structure, comprising an underframe body, an operating handle, a reclining pull rope and a gas spring pull rope, a cushion back-and-forth moving mechanism being installed on the outer side of the underframe body, the operating handle being installed through a left outer wall of the underframe body at a lower end of the cushion back-and-forth moving mechanism, a backrest installed on a rear end of the underframe body through a backrest connecting rod;

• and wherein a reclining elastic adjusting mechanism is arranged at a front end of an inner wall of the underframe body, a backrest angle adjusting mechanism is arranged at the inner wall of the underframe body on a right side of the reclining elastic adjusting mechanism, a cushion height adjusting mechanism is fixedly connected in the underframe body, a handle is arranged at a left end of the operating handle, a handle connecting block is arranged at a right end of the handle through a bolt, a slider locking control lever is fixedly connected at a middle part of a top end of the handle connecting block, a handle base is fixedly connected at a right end of the handle connecting block, a reclining rope groove is provided at one end of the handle base, a bottom end of the handle is provided with a gas spring pull rope groove, one end of the reclining pull rope is fixedly connected in the backrest angle adjusting mechanism through a groove, the other end thereof away from the backrest angle adjusting mechanism is fixed at a right end of the operating handle, one end of the gas spring pull rope is fixedly connected in the cushion height adjusting mechanism through a gas spring pull rope groove, the other end thereof away from the cushion height adjusting mechanism is fixedly connected at a lower end of the operating handle, and the right end of the handle is connected with the cushion height adjusting mechanism through the slider locking control lever.