Air turbine handpiece

Abstract

An air turbine handpiece having: a head portion with built-in free turbine blade, a neck portion installed consecutively with the head portion and grasped by an operator, a grip portion installed consecutively with the neck portion, an air supply duct for driving the turbine blade, and an exhaust duct for exhausting the air. The exhaust duct is provided with a reflux duct, open at one end to the exhaust duct, and open at the other end to the turbine room as the exhaust exit, a value in which an aperture at the reflux exit of the reflux duct is divided by an aperture in the air supply port of the air supply duct, becomes one or less, and the reflux exit of the reflux duct is opened to the turbine room near the air supply port between the air supply port and the exhaust exit.

Description

TECHNICAL FIELD[0001]The present invention relates to an air turbine handpiece used for dental therapeutics etc., particularly, an air turbine handpiece capable of improving the rotation efficiency of the turbine, in which when the turbine stops in case of ending use of the kind of air turbine handpiece, generation of negative pressure due to inertia rotation of the turbine blade is prevented in the turbine room and the reflux duct as a negative pressure prevention means is used as the promotion means of driving force at the time of driving the turbine again.BACKGROUND ART[0002]When the drive of the turbine is ended, the conventional air turbine handpiece intercepts the supply of the pressurizing air being as driving medium. However, even if the supply of the pressurized air is intercepted, the turbine blade continues the inertia rotation by own inertia force so that the air in the turbine room is exhausted by the inertia rotation, resulting in a generation of negative pressure ther...

AI Technical Summary

Benefits of technology

The present invention provides an air turbine handpiece that prevents foreign material from being inhaled and cross infection between patient and operator or among patients through the handpiece. This is achieved by directing exhaust from the handpiece back to the portion where negative pressures are generated, and reducing the negative pressure there. The reflux duct in the handpiece is simple and easy to manufacture, and can also help in reinforcing the rotation driving force and obtaining energy-saving effect. The value of the aperture at the reflux exit is set to one or less, allowing for increased supply of air and reinforcement of the rotation driving force. Overall, the air turbine handpiece of the present invention is low-cost and efficient in preventing cross infection and can also improve the energy-saving performance.

Problems solved by technology

However, even if the supply of the pressurized air is intercepted, the turbine blade continues the inertia rotation by own inertia force so that the air in the turbine room is exhausted by the inertia rotation, resulting in a generation of negative pressure therein.

Moreover, the air in the turbine room is communicated with ambient air through the gap in surroundings of rotation axis so that interior of the turbine room becomes a negative pressure, resulting in generation of negative pressure in the turbine room.

Moreover, the air in the turbine room is communicated with the ambient air through the gap in surroundings of rotation axis, so that the interior of the turbine room becomes a negative pressure, resulting in a inhalation of ambient air in the turbine room, and resulting in a inhalation of contaminant such as saliva and blood etc. of patient together with the inhalation of ambient air.

As a result, the interiors of the joint metal fittings and the feed and exhaust hoses which are connected to the interior of the head portion and / or the handpiece, are polluted.

Moreover, in addition to the above constitution, the space between the turbine blade and upper and lower internal wall surface of the chamber is made narrow, particularly, an increase in the torque that caused to rotate the cutting tool.

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