Rotary Shaft Seal Lip Geometry for Lower Sliding Torque

The side lip is divided into multiple sections along its length, with grooves created at specific positions. This segmentation allows different portions of the side lip to have different functions: some portions contact the deflector for sealing, while others have reduced contact or clearance to minimize sliding torque. The grooves create distinct zones that separate the sealing function from the low-friction movement function.

Different portions of the side lip are given different geometric properties through the grooves. The sections between grooves maintain the necessary contact pressure and surface area for effective sealing, while the groove regions provide reduced contact zones that lower sliding resistance. This local variation in geometry optimizes both sealing performance and torque characteristics at different locations along the side lip.

The bent distal end portion is segmented by grooves that create zones of varying contact. The bending maintains overall contact pressure for foreign matter prevention, while the grooves introduce localized reduction zones that decrease the cumulative sliding torque. This allows the bent configuration to serve dual purposes: maintaining sealing pressure while reducing frictional losses.

The grooves change the geometric parameters of the side lip by introducing variations in thickness and contact surface area at specific locations. These parameter changes allow the distal end to maintain the bent configuration for sealing while creating local regions of reduced contact that lower the sliding torque. The groove depth and positioning are optimized to balance contact pressure maintenance with torque reduction.