Abstract:
In order to detect the angular position of a permanent magnet rotor (13) of a brushless motor, measuring means are connected to the windings of the stator in such a way as to form an oscillatory circuit and the variations in the frequency of resonance as a function of the position of rotor are measured. In order to augment these variations, the rotor has a non-magnetic structure (26) around the magnet (14) with zones of different thicknesses or of different permeabilities. This structure can be formed by a metal sleeve, of brass for example, having openings or recesses (44) which can be filled with a dielectric material.
Abstract:
The arrangement comprises an external supply unit that feeds into two flexible conductors (5, 5') a variable d.c. voltage (V.sub.A) superposed on a modulated high frequency voltage (V.sub.C), the modulation being dependent on the position of a switch. The arrangement further comprises, inside a handpiece, means (20, 21) connected to the conductors for receiving therefrom and separating the two voltages, means (23, 25, 26, 27, 28, 29) for feeding a supply voltage (V.sub.D) to the circuits of the handpiece, means (30, 31, 33, 34) for demodulating the high frequency voltage and for generating a logic signal (S.sub.L) representative of the position of the switch, a three-phase motor, sensors (A, A', A") controlled by the motor, an inverting circuit (41) receiving the logic signal, a control circuit (50), and a drive circuit (60) issuing a three-phase signal (S.sub.M, S'.sub.M, S".sub.M) to the terminals (X, X', X") of the motor.The speed of the motor is determined by the d.c. voltage being applied and the direction of rotation is determined by the position of the switch.
Abstract:
A supply pipe for connecting an instrument for dental or surgical use to a control and supply unit contains fluid conduits and electric lines and includes at a front end a universal coupling for connecting different types of the instrument in a removable manner to part or all of the conduits and lines. The universal coupling includes fluid connectors coupled to conduits and electric connectors coupled to lines, wherein each of the connectors occupies a place on a front face of the universal coupling. The supply pipe contains at least one additional electric line including an additional conductor which is not coupled to one of the electric connectors, but to one of the fluid connectors of the universal coupling, wherein the dual function connector is arranged to provide a choice between a fluid connection, an electric connection or both.
Abstract:
The invention relates to a handheld part for dental or surgical use that comprises static components, i.e. head and body, and dynamic components, i.e. dented wheels, drivers, turbines, characterized in that some at least of the static and/or dynamic components are made of a metallic alloy that solidifies at least partially in an amorphous phase in the volume.
Abstract:
A supply pipe (1) for connecting an instrument for dental or surgical use to a control and supply unit contains fluid conduits and electric lines and includes at a front end a universal coupling (4) for connecting different types of said instrument in a removable manner to part or all of said conduits and lines. The universal coupling includes fluid connectors (6 to 9) coupled to said conduits and electric connectors (20 to 23) coupled to said lines, each of said connectors occupying a place on a front face (11) of the universal coupling. The supply pipe (1) contains at least on additional electric line including an additional conductor (24) which is not coupled to one of said electric connectors (20 to 23), but to one (7) of the fluid connectors of the universal coupling (4), said dual function connector being arranged to provide a choice between a fluid connection, an electric connection or both. The additional conductor (24) can be inside or outside the flexible tube (17) forming the fluid conduit, or even in the wall of said tube.
Abstract:
In order to allow a dental instrument such as an air turbine or an electric motor hand piece to be quickly connected or disconnected to a supply unit, a revolving connecting unit is provided with a fixed portion (4), provided with channels (13 to 16) for fluids and electric contact rings (26) at the front, a coupling sleeve (32) freely rotating on the fixed portion, an a stop ring inserted between said sleeve and the fixed portion and rotating freely thereon. The coupling sleeve (32) is secured to the back of the instrument by a bayonet device (38). This sleeve extends far enough forwards to prevent accidental contact between the electric contact rings (26) and an external object when the connecting unit is not connected to an instrument.
Abstract:
The invention concerns a multi-purpose revolving connecting assembly intended to connect dental instruments (1a, 1b) having rear portions (22) of different geometrical configurations to a supply source (S).This connecting assembly is characterized in that it includes a nut (16) formed, at the front, of a removable sleeve (50a, 50b) and, at the rear, of a bush (52) which can be connected to the sleeve (50a, 50b) by a screw-nut system, the sleeve (50a, 50b) being provided to be fixed onto the dental instrument (1a, 1b), while the socket (52) has a support surface (58b) intended to abut against the ring (4) axially holding a mobile coupling piece (28a, 28b) on a fixed coupling piece (26).