Patent ID: 6485256
Filing Date: 2002-11-26
Classification: F04D,F16C

Abstract:
A seal apparatus for a water pump provided between a non-rotating member having an inner peripheral surface and a rotating shaft of the water pump inserted into the non-rotating member and having an outer peripheral surface; comprising a seal ring having an outer peripheral edge fastened to the inner peripheral surface of the non-rotating member, and a singer having an outer peripheral surface and a side surface, and fitted around the rotating shaft to block between the inner peripheral surface of the non-rotating member and the outer peripheral surface of the rotating shaft of the water pump, the seal ring comprising a first seal lip that comes in sliding contact with the outer peripheral surface of the rotating shaft or with the outer peripheral surface of the singer that rotates together with the rotating shaft, and a second seal lip that has a tip edge which comes in sliding contact with the side surface of the singer, and that is tilted outward in the radial direction toward the tip edge thereof, wherein the amount of compression of the second seal lip, which occurs when the tip edge of the second seal lip comes in contact with the side surface of the singer, is at least {fraction (1/10)} and up to {fraction (7/10)} the height of the second seal lip in a free state, and the roughness of a side surface portion of the singer with which the tip edge of the second seal lip comes in sliding contact is from 0.2 &mgr;m to 2.0 &mgr;m in the arithmetic mean Ra, or is from 0.8 &mgr;m to 8.0 &mgr;m in the maximum height Ry.