Instrument for the treatment of dental canals
AssigneeFluckiger & Huguenin S.A.
InventorFrancois Cattin
Life of this patent
Estimating the term…
Abstract
An instrument for use in the treatment of dental canals. The instrument includes a tool such as a pulp-burr or reamer connected by a friction coupling or slip-clutch to a mandrel driven by power to rotate the tool. Should the tool jam in a dental canal, the clutch allows the mandrel to rotate by slipping relatively to the tool thus avoiding application of excessive torque to the tool which might break it. The slip-clutch can be a helical spring fast with one end of the tool and fitted in a cylindrical bore in and co-axial with the mandrel, the spring being stressed so some of its turns press against inner surfaces of the bore to provide the friction coupling between the spring and bore.
Claims11
An instrument for the treatment of dental canals comprising:
- a mandrel having a substantially cylindrical bore extending axially of said mandrel;
- and a pulp burr comprising a helical wire having a helical extension fitted in the substantially cylindrical bore under stress, the cylindrical bore and the helical extension fitted in the cylindrical bore under stress together comprising drive transmitting means having a torque-limiting function for transmitting rotation of the mandrel by friction to the pulp-burr wherein said extension is of substantially cylindrical helical form which prior to being fitted under stress in the cylindrical bore is bent at an angle to the axis of the helical pulp-burr.
An instrument for the treatment of dental canals comprising:
- a mandrel, a tool fitted to said mandrel, and drive transmitting means having a torque-limiting function for transmitting rotation of the mandrel by friction to said tool, said drive transmitting means comprising a cylindrical bore in the mandrel, said bore extending axially of the mandrel, the tool having a shank fixed to an end of a coil spring, said spring being disposed under stress in the bore, and prior to said spring being disposed in the bore the spring being bent at an angle to the axis of the shank.
Dependencies are inferred from the claim text.