| 摘要 |
1367733 Rotor and bearing replacement pack for a miniature highspeed turbine DENTAL MFG ENG Ltd 6 March 1973 [4 April 1972] 15531/72 Heading B8C [Also in Division A5] A rotor and bearing replacement pack for a miniature high-speed turbine of the kind comprising a rotor having a stub-shaft extending on each side thereof journalled in respective bearings which carry resilient O-ring supporting and sealing members, comprises such a rotor with bearing members mounted thereon orientated correctly for insertion into the respective turbine housing 3, contained within a cylindrical sleeve 10 of plastics material, or metal, dimensioned to hold the rotor and its associated parts snugly, and to be engageable with the turbine housing to permit the rotor and bearings to be slid into the turbine housing as a unit, by a plunger 6 associated with the sleeve 10. In order to replace the rotor of a miniature turbine 3 forming the head of a dental handpiece 4, Fig. 1, a cap 2 of the turbine 3 is unscrewed, using a clamp 1, and a dental burr 5 in the head 4 is used to push the rotor and its outer bearing, not shown, out of the turbine 3. The tapered stem 6 of the plunger in the sleeve 10, Fig. 3, is then introduced into the turbine to jam into the inner bearing therein the latter then being extracted by pulling on the sleeve 7, Fig. 2. The cap 9 is unscrewed from the sleeve 10 which is then screwed on to the turbine 3 in place of the cap, Fig. 4, the stem of the plunger 6 then being pushed to transfer the rotor bearing assembly from the sleeve 10 smoothly into the emptied turbine 3. Finally, the sleeve 10 is unscrewed from the turbine head 3 and the cap 2 is replaced, and tightened, by the tool 1. In the case of handpieces incorporating ballbearing turbines the bearing at the burr mounting end is expelled along with the rotor and other bearing by pressure on the burr so that, in this case, the tapered stem of the plunger does not have to be used as an extruder tool. |
