Diving bell submersible seal

A submersible seal disposed at least partially in a body of liquid for protecting a motor from liquid intrusion and damage, the motor including a sealed fluid tight casing having a single shaft opening and a rotatable shaft which extends therethrough, the submersible seal comprising, in combination:

• a stationary seal element mounted to the casing of the motor, the stationary seal element comprising a tubular section surrounding but spaced from the motor shaft and extending along a substantial length thereof proximate the casing, and
• a rotating seal element attached to the shaft at the distal end inter-engaged with the stationary seal element to form a labyrinth passageway, the labyrinth passageway having a first end at the casing of the motor, a second end opposite the first end, and at least one reverse bend therebetween, the labyrinth passageway including an air-filled segment which extends through the reverse bend and blocks the passage of liquid from infiltrating the casing of the motor.

A submersible seal disposed at least partially in a body of liquid for protecting a motor from liquid intrusion and damage, the motor including a sealed fluid-tight casing having a shaft opening and a rotatable shaft which extends therethrough, the submersible seal comprising, in combination:

• a stationary seal element connected to the casing of the motor at the shaft opening and having a cylindrical tubular section surrounding a length of the shaft proximate the casing;
• and
• a rotating seal element attached to and surrounding a portion of the shaft at the distal end thereof, the rotating seal element being inter-engaged with the stationary seal element to form a labyrinth passageway having a first end at the casing of the motor, a second end opposite the first end open to the body of liquid, and at least one reverse bend therebetween, the labyrinth passageway comprising a sealed passageway for trapping an air cushion compressed by liquid from the body of liquid entering the first end, the air cushion extending through at least one reverse bend to prevent flow of liquid past the air cushion thereby to protect the motor from ingress of liquid.