Patent ID: 7931278
Filing Date: 2011-04-26
Classification: F16J

Abstract:
1. A seal assembly for sealing a gap between a rotary member and a fixed member housing the rotary member, so as to prevent passage of a fluid from a first environment to a second environment located on opposite sides of said gap, said seal assembly comprising: a first ring integral with said rotary member; a second ring integral with said fixed member; and an elastically deformable sealing member integral with said second ring, and comprising a single sealing lip cooperating in a fluid-tight manner with a mating portion of said first ring, and an annular lip for retaining fluid; wherein on the side cooperating with said mating portion, said sealing lip comprises a spiral groove which, in use, produces a fluid-dynamic pumping effect to pump said fluid away from the sealing area and towards the first environment; wherein a cooperation area between the sealing lip and the mating portion extends radially with respect to an axis, about which the rotary member can rotate; wherein the sealing lip comprises an end portion cooperating in fluid-tight manner with a mating portion of the first ring and extending orthogonally with respect to an axis, about which the rotary member can rotate; wherein the cooperation area between the end portion of the sealing lip and said mating portion extends orthogonally with respect of such axis, so that such cooperation area is annularly-shaped, and thereby bounded between two circumferences having the same centre on such axis; wherein the cooperation area extends radially enough to allow at least three spires of said groove to face the mating portion of the first ring; and wherein the extension of said cooperation area measured radially to said axis is more than 10% of the distance between said axis and farthest point of said end portion of said sealing lip from said axis.