Mechanism for converting rotary motion into reciprocating linear motion

The utility model discloses a mechanism for converting rotary motion into reciprocating linear motion, which comprises a shell and a machine core mounted in the shell. The machine core comprises a motor, a motor fixing seat, a motor fixing screw, a transmission shaft, a first screw, a bearing, a sliding shaft sleeve, a damping rubber sleeve, a second screw, a damping rubber ring, a track shaft rear end, a third screw, a ball, a track shaft front end, a sliding shaft, a fourth screw, a connecting rod and a massage head. The motor is fixed on the motor fixing seat; a screw hole is formed in thetransmission shaft which is connected with a motor output shaft and fixed through a first screw; limiting ends are arranged on the two sides of the rear end of the sliding shaft sleeve, bearing fixinggrooves are formed in the middle of the rear end, bearings are installed in the bearing fixing grooves, and the limiting ends are sleeved with damping rubber sleeves. A positioning protrusion is arranged on a cylinder body of