Abstract: A dynamic seal advantageously utilizes a plurality of grooves on the active side or surface of the seal to capture a leaked lubricant and hydrodynamically pump the lubricant back into the lubricated side of the seal. The grooves are interrupted at an intermediate location by a continuous circumferential band that aids in preventing leakage past the band when the shaft is not rotating and the grooves on both sides of the band pump contaminants away from the sealing lip.

Abstract: A dynamic seal utilizes a groove on the active side of the seal to capture a leaked lubricant and pump the lubricant back into the lubricated side of the seal. The groove stops short of the leading edge of the seal that faces the lubricant side forming a static dam between the termination point of the groove and the seal edge. When the fluid pressure within the groove exceeds the opening pressure for the seal lip, the lubricant within the groove is pumped back into the lubricant side of the seal. The groove can have an induction zone wherein the fluid pressure rise is gradual and a booster zone wherein the fluid pressure rise is relatively faster than in the induction zone. The booster zone is disposed adjacent the static dam. Bars are provided across the spiral grooves to prevent contaminants from reaching and becoming trapped in the booster zone.

Abstract: A dynamic seal advantageously utilizes a plurality of grooves on the active side or surface of the seal to capture a leaked lubricant and hydrodynamically pump the lubricant back into the lubricated side of the seal. The grooves are interrupted at an intermediate location by a continuous circumferential band that aids in preventing leakage past the band when the shaft is not rotating and the grooves on both sides of the band pump contaminants away from the sealing lip.

Abstract: A dynamic seal utilizes a groove on the active side of the seal to capture a leaked lubricant and pump the lubricant back into the lubricated side of the seal. The groove stops short of the leading edge of the seal that faces the lubricant side forming a static dam between the termination point of the groove and the seal edge. When the fluid pressure within the groove exceeds the opening pressure for the seal lip, the lubricant within the groove is pumped back into the lubricant side of the seal. The groove can have an induction zone wherein the fluid pressure rise is gradual and a booster zone wherein the fluid pressure rise is relatively faster than in the induction zone. The booster zone is disposed adjacent the static dam. Bars are provided across the spiral grooves to prevent contaminants from reaching and becoming trapped in the booster zone.