BOOT SEAL

Boot Seal An elastomeric seal apparatus having an inner annular terminating portion which is attachable to a first member, an outer annular terminating portion which is attachable to a second member, and an annular convoluted flexible portion which is disposed between the inner and outer terminating portions and has an inner and an outer margin which are respectively joined thereto. The thickness of the convoluted flexible portion decreases from the relatively thicker inner margin to the relatively thinner outer margin in proportion to a radial distance extending from the inner margin to the flexible portion. A concentrically inner convolution and a concentrically outer convolution constitute the flexible portion and have a relatively small and a relatively large radius of curvature. When the inner and outer terminating portions are relatively reciprocated with the first and second members about a longitudinal seal axis , the tapered, convoluted structure of seal apparatus exhibits extended life as a result of substantially equalizing the maximum uniform strains induced therein.