Patent ID: 6565096
Filing Date: 2003-05-20
Classification: F16J

Abstract:
A lip type seal structure comprising:a housing (1) having a sealed space (S1) therein and an inner circumferential surface, a rotary shaft (2), a first lip member (32) having an inner circumferential seal part and an outer circumferential part, a second lip member (33) having an inner circumferential seal part, a third lip member (34) having an inner circumferential seal part, a pressure durable reinforcing ring (35) for reinforcing the first lip member (32), a first rear surface support plate (36) for supporting the second lip member (33), a front surface support plate (37) for supporting the third lip member (34), a second rear surface support plate (38) for supporting the third lip member (34), the first lip member (32), the second lip member (33) and the third lip member (34) being arranged in order between the sealed space (S1) and atmosphere (A), the outer circumferential part of the first lip member (32) being fixed to the inner circumferential surface of the housing (1), the second lip member (33) having the inner circumference seal part extends bendingly from a diametral direction part toward the sealed space (S1) and forms a seal between the rotary shaft (2) and the first lip member (32), the third lip member (34) being located between the second rear surface support plate (38) and the front surface support plate (37) so that the third lip member (34) forms a seal between the second lip member (33) and the atmosphere (A), the pressure durable reinforcing ring (35) being located between a rear surface of the first lip member (32) and the second lip member (33) and limiting deformation of the first lip member (32), the rear support plate (36) being located between the second lip member (33) and the front support plate (37) and limiting deformation of the second lip member (33), the second rear surface support plate (38) being located between the third lip member (34) and a support surface of the housing (1) facing in an axial direction so as to limit deformation of the third lip member (34), the front surface support (37) being located between the first rear surface support plate (36) and the third lip member (34) and including a stopper extending adjacent to a rear surface of the inner circumferential part of the first rear surface support plate (36) for preventing the first rear surface support plate (36) from contacting the rotary shaft.