Shaft seal structure

The invention discloses a shaft seal structure which comprises an inner sleeve and an outer sleeve, a sealing structure fixedly connected to the outer sleeve is arranged on the inner sleeve, a lost channel is formed in the sealing structure so that invasion of foreign matter can be prevented, the foreign matter can be extruded out of the lost channel only by filling oil liquid during maintenance, maintenance is simple, and the shaft seal structure is high in practicability. Meanwhile, the sealing device further comprises a first sealing ring and a second sealing ring, the cross section of the second sealing ring is a concave face with a notch, pressure can be generated on the side walls of the rings when oil liquid is filled, the sealing effect is enhanced, the invasion degree of foreign matter is reduced, and the maintenance cost is reduced; and a plurality of rolling balls are arranged in the annular groove, and the outer sleeve is externally connected with the elastic composite sleeve, so that better suppo