A crank and rocker mechanism demonstration teaching aid used in teaching

The utility model discloses a crank and rocker mechanism demonstration teaching aid used in teaching. The teaching aid comprises a bottom plate, gear transmission supports, supports, a hull, a gear transmission device, and a rocker mechanism, wherein first bearing pedestals are fixedly mounted at the top of each support; the two sides of the hull are connected with the two ends of a horizontal shaft through connecting pieces; the two ends of the horizontal shaft are fixed on the first bearing pedestals at the tops of the two trapezoid supports respectively in a relatively rotated manner; the gear transmission device is fixed at one end of each gear transmission support through second bearing pedestals; one end of the rocker mechanism is fixed on the gear transmission device in a relatively rotated manner, so that the rocker mechanism may perform reciprocating motion with the gear transmission device in a vertical plane; the other end of the rocker mechanism is fixed at one end of horizontal shaft so as to dri