Patent ID: 9044290
Filing Date: 2015-06-02
Classification: A61C

Abstract:
1. A joint for connecting a motor unit to a power cord of a dental handpiece, comprising: a generally cylindrical motor casing, a motor unit detachably accommodated in said motor casing and supplying driving force to a dental tool, a generally cylindrical end cap connected to a hose which accommodates a power cord for supplying power to the motor unit, and detachably connectable to one end of the motor casing, and a motor-unit-side connector and a power-cord-side connector arranged between the motor casing and the end cap for mutual electrical engagement, said motor casing having an opening at its end to be connected to said end cap, said end cap having an opening at its end to be connected to said motor casing, connection of the motor casing to the end cap causing said motor unit to be electrically connected to the power cord, wherein said motor-unit-side connector is connected to the motor unit and arranged projecting outwards from the opening of the motor casing, and said power-cord-side connector is arranged offset from the opening of said end cap into an interior of the end cap, wherein said motor casing has a step protruding from the opening of the motor casing, and having a smaller outer diameter sized so that said opening of the end cap is capable of fitting thereon, wherein said step has male thread formed on its outer circumference, said thread having a smaller outer diameter than the rest of the motor casing, and said end cap has female thread formed circumferentially on its inner surface near the opening, so that the motor casing is capable of being screwed and fixed to the end cap, wherein said male thread is located distal to the motor-unit-side connector, and said female thread is located distal to the power-cord-side connector, and wherein said motor-unit-side connector projects beyond the step and the male thread formed on its outer circumference, and said power-cord-side connector is arranged offset beyond the female thread.