Dental turbine drive
AssigneeSiemens Aktiengesellschaft
InventorJuergen Wohlgemuth
Life of this patent
Estimating the term…
Abstract
A dental turbine drive which is provided with an arrangement to prevent suctioning of particles after deactivation of the drive air into the return air line. To accomplish this, the turbine space is closed during a run-out phase of the rotor except for an outflow channel that is arranged close to the axis of the rotor shaft adjacent the tool side and is connected to a return air channel. The return air channel can discharge directly into the outflow channel at a point spaced from the main portion of the rotor and a valve arrangement may be presented for closing the air opening once the input air has been interrupted.
Claims13
In a turbine drive for a dental handpiece comprising a housing with a turbine space, a rotor having a first shaft portion with a first bearing and a second shaft portion with a second bearing being mounted by the bearings for rotation in the housing with the first shaft portion extending from the housing and having means for holding a processing tool, said housing having a delivery channel for directing a flow of air on the rotor and a return air channel with a discharge opening for removing air from the turbine space, said discharge opening being located between said bearings, the improvements comprising means for preventing suction of air through the first bearing and into the return air channel during a run-down phase of the rotor, said means for preventing including the turbine space being closed during the run-down phase of the rotor except for an outflow channel arranged close to the axis of the rotor shaft of the first rotor shaft portion and being connected to the discharge opening of the return air channel.
In a turbine drive for a dental handpiece comprising a housing with a turbine space, a rotor having a first shaft portion with a first bearing and a second shaft portion with a second bearing being mounted by the bearings for rotation in the housing with the first shaft portion extending from the housing and having means for holding a processing tool, said housing having a delivery channel for directing a flow of air on the rotor and a return air channel for removing air from the turbine space, the improvements comprising means for preventing suction of air through the first bearing and into the return air channel during a run-down phase of the rotor, said means for preventing including the turbine space being closed during the run-down phase of the rotor except for an outflow channel arranged close to the axis of the rotor shaft of the first rotor shaft portion and being connected to a discharge opening of the return air channel, and said means for preventing including said first shaft portion having guide vanes on a circumference in the tool proximate region, said guide vanes being constructed so that during rotation of the rotor, the guide vanes direct an air flow along the shaft portion toward the means for holding a tool.
In a turbine drive for a dental handpiece comprising a housing with a turbine space, a rotor having a first shaft portion with a first bearing and a second shaft portion with a second bearing being mounted by the bearings for rotation in the housing with the first shaft portion extending from the housing and having means for holding a processing tool, said housing having a delivery channel for directing a flow of air on the rotor and a return air channel for removing air from the turbine space, the improvements comprising means for preventing suction of air through the first bearing and into the return air channel during a run-down phase of the rotor, said means for preventing including the turbine space being closed during the run-down phase of the rotor except for an outflow channel arranged close to the axis of the rotor shaft of the first rotor shaft portion and being connected to a discharge opening of the return air channel, and means for closing the discharge opening of the return air channel during the run-down phase of the rotor.
Dependencies are inferred from the claim text.