Abstract: Device for fixing drill bits into the head of air motors for hand-held dentists' tools, of the type incorporating a clip in the rotor inside which the shank of the drill bit is inserted. The fixing clip (6) includes longitudinal slits (7) and is acted on at one of its ends by an elastic means which tends to close the head (10) of the clip (6) on to the drill shank by the cooperation of an inclined surface (11) formed on the head of the clip with a matching inclined surface (12) formed on the inside face of the rotor (2), the head of the air motor being further provided with means which allow the shank of the drill to be released, by compressing said elastic means.

Abstract: A dental handpiece has a hollow main body enclosing a central rotating spindle equipped with tool grip means adjacent its forward end; spring means effects axial movement of the spindle in an inward direction for actuating the tool grip means to provide a gripping function and release means moves the spindle outwardly against the bias of the spring means for deactivating the tool grip means with the release means including a unitary plate removably mounted in the main body with first and second levers being pivotally mounted on opposite sides of the plate so as to be substantially positioned within the confines of the main body; driving ends of the levers are engageable with the spindle for moving the spindle axially outwardly of the main body to deactivate the grip means. The levers are on diametrically opposite sides of the axis of the handpiece and are mounted for pivotal movement in a plane passing through the axis of the hand instrument.

Abstract: Anaesthetic may be injected directly into the bone using a syringe in combination with a mechanism for causing the syringe needle to oscillate about its axis. The mechanism may be driven by a drive unit of the type conventionally used to power dental instruments.

Abstract: It consists of a movable guide (3) surrounding the drill and attached to the head of the hand-tool by way of elastic means able to be compressed, the frontal portion (7) of the said guide (3) during the whole duration of the drilling being applied against the gum which it compresses, and the guide including a bore through it for the drill (2) to pass through.

Abstract: This device for preventing the ingress of water into the head of a dental contra-angle comprises a ring seal of cylindrical configuration adapted to be inserted through a hole formed in the bottom wall of the head body for the passage of the dental tool. This ring seal comprises at one end a flange having a diameter greater than the diameter of the passage hole and at its opposite end a bead also of greater diameter than the hole but adapted to be compressed when inserting the ring seal through the hole.

Abstract: An air distributor for the supply of a blade-type motor which can be rotated about its axis by means of a sleeve with which it is integral external to a casing, the rear end plate of the blade-type motor being constituted by a ring traversed by at least three openings which are off set at angles of 120.degree., characterized in that the end of the distributor facing the said ring is shaped so as to form, on the one hand, a chamber causing the outlet openings of the motor block to communicate with one or more outlet pipes for the air toward the exterior traversing the distributor and, on the other hand, a surface in direct contact with the said ring, on which surface there merges a feed duct for air traversing the said distributor originating from the compressed air source.Application: to hand-held dental instruments.

Abstract: This plate for packaging dental root-canal instruments comprises a support formed with recesses adapted to receive the instruments and a protection cover which is a slide fit on the plate. The recesses consist of parallel elongated cavities extending at a short distance from, and at right angles to a longitudinal edge of the support, and comprise each an extension in the form of a neck towards the opposite longitudinal edge. The support also comprises a flat central area somewhat recessed in relation to the bottoms of the necks in order to facilitate the gripping of the instruments' shanks.

Abstract: This air-water mixer for the atomizer of a dental hand piece comprises a body formed with a circular chamber into which open an air supply conduit, a water supply conduit and an outlet conduit for the fluids. One wall of this chamber consists of the inner face of a selector ring mounted for free rotation in the chamber, the inner face of the ring comprising a flat sector adapted to close the inlet port of one and/or the other supply conduits in predetermined positions of the ring, and an inclined sector permitting the free passage of fluid between one and/or the other of the supply conduits and the outlet conduit in other predetermined positions of the ring, this mixer being particularly suited for a dental hand piece provided with an air-water atomizing conduit.

Abstract: A modular reduction gear for a dental handpiece comprises an input shaft coupled to the driving motor and provided with a pinion constituting the sun wheel of an epicyclic gear of which the planet carrier is rigid with the adjacent end of the output shaft transmitting the rotary motion to the dental instrument, the carrier supporting three planet pins having mounted thereon for free rotary motion three planet pinions meshing with the sun pinion and with a fixed toothed annulus clamped between the pair of sockets constituting the body of the handpiece.

Abstract: In a dental handpiece, in particular a contra-angle, comprising a head and a handle coupled with a bayonet joint, an internal support for a tool-driving shaft fits freely in the head and has a rear portion fitting freely in the handle. In the vicinity of the coupling between the head and handle, the internal support has an enlargement providing a forwardly facing shoulder and a rearwardly facing shoulder. A groove at the base of the forwardly facing shoulder receives an O-ring. When the head and handle are coupled, the enlargement and O-ring are clamped between internal shoulders in the head and handle to position the internal support and restrain it from rotating.

Abstract: This dental handpiece comprises means for controlling the delivery of compressed air and water to an outlet conduit leading to the head of the handpiece. The water and air supply conduits from the motor open each into a circular groove formed in the inner periphery of a socket easily fitted on the tool holder retaining end of the motor. Radial ports formed in the socket open on the one hand into the grooves, respectively, and on the other hand into an annular chamber formed between the socket and the handpiece body, the outlet conduit extending from this chamber. A rotary ring accessible from outside the handpiece body is provided with a pair of seals off-set axially and angularly to each other and so arranged that in two end positions of the ring one of the two supply conduits is closed while the other conduit is open, and that in an intermediate position both conduits are open.

Abstract: This dental hand piece, notably of the contra-angle type, comprises three sleeve-like members assembled to each other by screwing and an external socket covering these three sleeves so as to clamp them between an inner shoulder formed at the front end of the socket and the front end of a complementary end sleeve fitted on the rear sleeve and to which the external socket is screwed at its rear end.

Abstract: This fixing device comprises a clamping claw consisting of a pair of diametrally opposed semi-cylindrical curved shells each connected by means of a small bar parallel to the shell generatrices to an end pivot pin, the bars extending on either side of the shells. An axial bore is formed through the claw and the pair of pivot pins are provided, in the vicinity of their junction with the corresponding bars, with a circular land having a diameter at least substantially equal to that of the shells, a cylindrical sleeve of flexible and sterilization-resistant material being slipped over these lands and extending therebetween in order to impart the necessary fluid-tightness to the axial bore in relation to the interior of the handpiece.

Abstract: This composite insert for injecting a liquid product under pressure into a member provided with an internal bore comprises first and second coaxial rigid sockets surrounding the outlet aperture of the container filled with said product, the first socket comprising an external flange and the second socket comprising an internal shoulder adapted to engage an internal abutment element of the member, the front end of the second socket comprising an external flange. A flexible resilient sleeve fits around the second socket and bears with its ends against the external flanges of the first and second sockets so that when an axial pressure is exerted against the second socket by means of the internal abutment element of the member the second socket is sunk more or less into the first socket, thus causing an elastic deformation of the sleeve which develops a bead engaging in a fluid-tight manner the wall of the inner bore of the member.

Abstract: This device for locking a dental tool in a handpiece of the contra-angle type comprises a keeper plate slidably mounted on the external surface of the holder and rigidly associated with a control member formed with a thumb-piece consisting of an inclined surface portion thereof. A keyhole formed in the keeper plate is engaged by a suitable shaped end portion of the tool shank so that when the keeper plate is moved to its release position the tool shank can pass through the larger portion of the keyhole and when the plate is in its locking position to which it is urged by a return spring the end portion of the tool shank engages the narrow portion of the keyhole.

Abstract: A contra-angle tool holder head notably for dental drills and cutters, for rotatably driving in opposite directions two coaxial dental tools such as drills or cutters comprises a first holding member adapted to drive the first tool and consisting of a claw supporting a first bevel pinion and a second holding member for rotatably driving the second tool in the opposite direction, this second holding member consisting of a second hollow bevel pinion, both holding members being driven simultaneously from a third bevel pinion carried by a shaft driven in turn from the motor and disposed between the first and second bevel pinions, the axis of the drive being disposed at right angles to the common axis of the first and second bevel pinions and of their holding members.