Isolated bearing viscous speed retarding device for rotary nozzles

A speed retarding device for a rotary nozzle comprising:

• a hollow cylindrical housing;
• a rotatable tubular shaft rotatably carried by the housing, the shaft having a drag sleeve portion in the housing and having a shaft end extending through at least one end of the housing, wherein the shaft end is adapted to receive a rotary nozzle thereon;
• a pair of lubricated support bearings supporting and sandwiching the drag sleeve portion of the shaft between the bearings in the housing;
• an annular axial inner seal between each of the support bearings and the drag sleeve portion isolating the drag sleeve portion from the support bearings, wherein the inner seals, the housing and the drag sleeve portion define a cavity within the housing;
• a viscous fluid confined within the cavity;
• and
• a plurality of centralizing vanes radially extending outward from the housing.

In a high pressure water blasting tool assembly having a rotatory nozzle for cleaning inside surfaces of a piping system, a speed retarding device connected between a hose and the rotary nozzle, the retarding device comprising:

• a hollow cylindrical housing;
• a rotatable tubular shaft rotatably carried by the housing, the shaft having a drag sleeve portion in the housing and having a shaft end extending through at least one end of the housing, wherein the shaft end is adapted to receive a rotary nozzle thereon;
• a pair of lubricated support bearings on the shaft supporting and sandwiching the drag sleeve portion of the shaft in the housing;
• an annular axial inner seal between each of the support bearings and the drag sleeve portion isolating the drag sleeve portion from the su ort bearings, wherein the inner seals, the housing and the drag sleeve portion define a cavity within the housing around the drag sleeve portion;
• a viscous fluid confined within the cavity;
• and
• an outer axial annular seal on the shaft adjacent to each support bearing whereby each lubricated support bearing is sandwiched between inner and outer annular seals in the housing and separated from the viscous fluid in the cavity.