Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
  • A61C1/08—Machine parts specially adapted for dentistry
  • A61C1/14—Tool-holders, i.e. operating tool holders, e.g. burr holders
  • A61C1/141—Tool-holders, i.e. operating tool holders, e.g. burr holders in an angled handpiece
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
  • A61C1/08—Machine parts specially adapted for dentistry
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
  • A61C1/08—Machine parts specially adapted for dentistry
  • A61C1/10—Straight hand-pieces
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
  • A61C1/08—Machine parts specially adapted for dentistry
  • A61C1/14—Tool-holders, i.e. operating tool holders, e.g. burr holders

Definitions

• the present invention relates to a device for fixing an instrument in a dental handpiece.
• Numerous devices for fixing dental instruments in handpieces are known in particular those designed to hold an instrument by hanging in a head in which the instrument is guided in rotation by separate means. This is for example the case of the device as described in patent EP 0 174 695.
• These devices generally call for radial displacement of mechanical components of the shoe type which come to cooperate with a shape of groove formed on the handle of the instrument. in which they engage, said shoes being maintained or recalled by a spring system.
• These embodiments in addition to the fact that they are expensive because they call on numerous parts, are bulky and lead to large head dimensions.
• the development of dentistry under the microscope requires the smallest possible instruments.
• the object of the invention is to propose a device for fixing the instruments which allows the production of heads of handpieces of small dimensions and of a reduced cost which is removable and applicable to parts with right hands and contra-angles.
• This object is achieved by the invention which consists of a device for fixing a dental instrument to a tool holder assembly for fixing and driving in rotation a dental tool or instrument around a drive axis.
• said tool holder assembly being integrated in a head of a dental handpiece, and coupled to a movement transmission assembly, integrated in a handle of said handpiece, characterized in that!
• the fixing device is removable relative to the tool holder and in that it is mainly composed of a deformable and elastic tightening-loosening means in the form of a belt, at least part of which has a section capable of engaging in a groove or groove by annular example which is provided in the upper part of the instrument and capable of holding said instrument by clamping forces, said loosening clamping means also comprising means for exerting loosening forces coming from meeting of the belt clamping forces to release the instrument.
• the clamping forces are due to the elasticity of the material or to the elasticity of the part and are exerted perpendicularly to the axis of the instrument, preferably at diametrically opposite points thereof.
• the belt made of elastic deformable material has a substantially parallelogram shape with a central zone provided for enclosing the head of the instrument at the level of a groove, the large diagonal of the parallelogram is provided so that its two ends protrude diametrically of the envelope of the head by two projections each placed in a notch of the head, the two projections constituting means for manually and directly exerting loosening forces on the belt.
• the belt has recesses provided near the projections and pressing on the periphery of a housing provided in the head to receive the fastening device.
• the elastic belt with a parallelogram shape and a central zone for enclosing the instrument has two ears forming protrusions perpendicular to the plane of the belt and situated on the same side thereof, the two ears constituting means for exerting loosening forces by means of a push button placed on the head of the handpiece.
• the fixing device also comprises a push button in several parts, namely: an elastic ring at the lower end which retains the push button on the head, an intermediate elastic zone which acts as a return spring for the push button, a cylindrical inner insert which allows, when the push button is pressed, to control the deformation of the elastic belt, thus releasing the tool.
• the insert has an internal conical shape to cooperate with conical blanks of the ears of the belt.
• the parallelogram belt also has a conical part formed on the underside of the central zone.
• the deformable elastic belt has the shape of an elastic split ring. More particularly, this split ring includes an upper cylindrical collar extended by a conical intermediate part and a transverse shoulder formed by segments directed towards the drive axis.
• the push-button comprises, on the underside, clipping hooks for cooperating with lights of a barrel pinion driving the instrument in rotation.
• FIG. 1 general three-dimensional view of a handpiece according to the invention
• FIG. 2 view in longitudinal section of the handpiece of FIG. 1
• FIG. 3 view in partial longitudinal section of a nonlimiting embodiment of the invention
• FIG. 4 representation in volume and partial of another nonlimiting embodiment comprising means of tightening loosening in the form of an elastic lozenge belt which can be released manually
• FIG. 5 view in axial section of the view in FIG. 4, FIG.
• FIG. 6 view in transverse and partial section of the head of FIG. 4, produced at the elastic belt
• FIG. 7 volume representation and partial section of the head of FIG. 4
• FIG. 8 view in axial section of another nonlimiting embodiment comprising a tightening means for loosening in the form of a belt ure elastic looseable by the action of a push button
• figure 9 representation in volume and in partial section of the embodiment of figure 8
• figure 10 representation in volume of the elastic belt of figures 8 and 9
• figure 11 view in axial section of another nonlimiting embodiment comprising a loosening tightening means in the form of a split ring
• FIGS. 12 and 13 volume representation of the push button in FIG. 11, FIGS.
• FIGS. 14 and 15 representation in volume of a clamping loosening device in the form of a split claw ring of FIG. 11,
• FIG. 16 volume representation of a push button in FIG. 3.
• FIGS. 1 to 3 General concept of the body of the handpiece. Reference is first made to the nonlimiting examples of FIGS. 1 to 3.
• a handpiece (1) consists of a body (2) in one piece comprising a part serving as a handle (3) d rectilinear axis and a part constituting a head (4), for fixing and driving an instrument (5) along a drive axis (6) which can be aligned with the axis of the handle (7) or which can form a predetermined angle with it, between 90 and 180 ° and preferably between 100 ° and 130 °, as on the nonlimiting example of the figures.
• the body is formed by an outer casing (8) or carcass, monobloc or not, which can be electrically insulating and which can for example be made of polymeric, thermoplastic or thermosetting material, (preferably polyether ether ketone for short PEEK in the continuation of the text) incorporating the mechanical components of the handle and the head as well as means of electrical connection, ensuring the transmission of the movement and of the electrical energy from a connection (9) provided at the end of the handle to cooperate with an external motor , not shown, up to the instrument (5) fixed in the head (4).
• the contra-angle (1) according to the invention shown in FIGS. 1 to 3 has two axes (6) and (7) making it possible to limit the hazards of friction specific to each bearing, in order to guarantee the most stable performance.
• a handpiece according to the invention connected and coupled to a motor can thus generate, for example, a rotation to an instrument (5) (channel instrument for example) and thereby convey, an electric current exploitable for the detection of the apex.
• the electrical connection between motor and handpiece can be made by any means of connection, for example between a motor attachment finger and an attachment groove (10) of a socket (11) (or by telescopic pusher for example).
• the insulating envelope (8) is held by the practitioner, and its end on the head side (4) has the patient's mouth as its environment.
• the chain of mechanical and electrical transmission members is constituted as follows in the handle: the electric current passes from the bush (11) to a fixed outer ring of a first bearing (12), and to a first spring (13), then to a fixed outer ring of a second bearing (14), then to a ring (15) stopped axially by a first shoulder in the casing (8), then to a spring (16) stopped axially by a second shoulder of the envelope (8).
• a barrel pinion (20) mounted on the drive shaft (6) has teeth (21) which can be meshed with the teeth (22) of an output pinion (23) of the handle.
• the barrel pinion (20) is conductive and integral with the inner rings of the bearings, it ensures the electrical conduct to the instrument (5) and the mechanical drive of the latter.
• the electric current conveyed to the end of the instrument will delimit the apex by a resistance variation effect, taking into account the external insulation of the envelope (8) and a push button (55 ) provided on the head (4) and which will be described later.
• This solution will be better understood on reading the two embodiments described below. We first describe a first embodiment in conjunction with FIGS. 4 to
• the housing (26) of the tool holder assembly (24) has on the one hand a cylindrical bottom part (29) coaxial with the drive axis (6) and whose diameter is suitable for receiving the barrel (30) of the barrel pinion (20), and on the other hand a substantially cylindrical upper part (31), also coaxial with the drive axis (6), and of larger diameter and designed to receive the toothing ( 21) of the pinion-barrel with its means of engagement of the instrument as well as the clamping-loosening device thereof described below.
• the opening (27) emerging from the upper part of the housing (31) is closed by a plug or cap (28), preferably but not necessarily made of the same material as the casing (8).
• the upper part of the housing (31) also has a lateral opening (32) opening into an internal housing (33) of the handle (3) so as to allow the gear teeth of the pinion (20) to mesh with the teeth of the output pinion (23) of the handle (3).
• the pinion was freely rotated in the head and its axial strength is ensured between on the one hand the bottom (34) of the upper part of the housing which forms a shoulder, and on the other hand the front face (35) of the plug.
• the resulting axial freedom of said barrel pinion is a few hundredths of a mm.
• the rotational movement of the output pinion (23) is transmitted to the barrel pinion (20) then to the instrument (5) by means of a flat (36) provided on the instrument and cooperating with a flat (37) provided in the internal bore (38) of the barrel pinion.
• the blanks (44) of the notches ensure the rotation blocking of the belt, which is centered in the head by means of recesses (45) provided near the projections (42) and resting on the periphery (46) of the part upper part of the housing (26).
• the axial holding of the belt is ensured on the one hand by a shoulder (47) provided in the bottom (48) of an axial cavity (49) of the plug intended to receive the head of the instrument (40) and of on the other hand by the bottom (50) of the notches. In this way the belt does not touch the rotating part of the barrel pinion.
• said belt cooperates with an upper shoulder (51) of the annular groove of the head of the instrument to produce a first axial limitation of said instrument, the other axial limitation being ensured by a flat (52) of the barrel pinion cooperating with the transverse end (53) of the flat part of the instrument.
• Unlocking the instrument consists in exerting two diametrically opposite supports on the projections (42), directed towards the axis of rotation. These two forces cause an orthogonal component thus releasing the instrument.
• the fact of pressing simultaneously and directly on the two ears of the belt guarantees the tightening in mouth, compared to the system with push button not example.
• the attachment of the instrument can be done without support on the two ears of the belt thanks to the arrangement of a conical part (64) practiced under the central zone (39) in the belt, the axial displacement of the instrument translating a radial displacement of the belt, by elasticity, the belt returns to its shape to ensure the tightening function.
• a second embodiment of the clamping-loosening device is now described in connection with FIGS. 8 to 10.
• the elastic belt (25) with a diamond shape and a central zone (39) for clamping the instrument is different of the previous one by its ears (54) forming protrusions perpendicular to the plane of the belt and situated in the same side of it, and by the fact that it is held axially and radially by the barrel pinion as shown in Figures 8 to 9.
• the two ends of the belt pass through two peripheral slots (61) provided on the upper flange (62) of the barrel pinion, diametrically opposite, and arranged in a plane transverse to the drive axis (6), the two ears (54) are locked in rotation by two notches (63) of said collar.
• the head differs from the previous one in that the plug is replaced by a push button (55) with metal insert for example (to facilitate manufacturing).
• the push button in PEEK for example, has several parts: - an elastic ring (56) at the lower end, which limits the axial freedom of the barrel pinion and retains the push button on the head ( 4), an intermediate elastic zone (57) which acts as a return spring for the push-button, an internal cylindrical insert (58) which allows, when the push-button is pressed, to control the deformation of the elastic belt, thus releasing the tool, for this purpose pressing the push button (55) compresses its spring (57) and makes the internal conical shape (59) of the insert (58) cooperate with the complementary conical blanks (60) ears of the belt.
• the resulting radial component on the ears (54) of the belt induces another radial deformation perpendicular to this primary component. This deformation allows the unlocking of the instrument.
• the introduction of the instrument into the head can be done with pressing the push button, or without pressing the push button, in this case a conical arrangement (64) below the central area (39) of the belt allows the introduction of the instrument.
• the configuration of the belt helps to ensure tightening by centrifugal effect during rotation. Push button concept
• this push button may be integral with the dynamic assembly (rotating, vibrating, etc.) for endodontics for example, and with a fixed push button, independent of the dynamic assembly.
• a handpiece head carrying a strawberry tail has already been presented above with reference to FIGS. 2 and 3. It will be recalled here that: a head body (4) which is one piece or not with the handle (3), receives a rotating barrel pinion (20) driven in rotation by an output pinion (23) of the handle. The barrel pinion therefore has freedom in rotation and an axial connection ensured for example by ball bearings. Solutions without ball bearings as in FIGS. 5 and 7 can of course be envisaged, with added plain bearings, or with plain bearings combined with the head body.
• the push button (55) in PEEK for example
• the ring (65) is externally cylindrical and its internal wall has an upper flange with a conical slope (71), a part intermediate shoulder-shaped (66) transverse directed towards the axis (6).
• the shoulder (66) of the elastic ring (65) retains, in the axial direction, the instrument (5) by engaging in the annular groove (41).
• the push button (55) is guided radially in the bore (38) of the barrel pinion by one or more sectors or members (87) arranged on the underside of the push button (55) and each terminated by a conical end used to make the or the supports on the elastic ring (65).
• the axial movement of the push button (55) is limited between the upper and lower ends of one or more openings (68) made in the upper body of the barrel pinion and in which cooperate one or more hooks (67) provided on the underside of the push button.
• the elastic ring (65) exerts an axial component on the push button (55) recalling the latter to its initial position.
• the clamping-loosening means is a split elastic ring open in a radial plane visible on the cutting plane of FIG.
• a push button independent of the dynamic assembly In the tool maintained position, the solution is characterized by a separation of the push button and the locking means.
• An embodiment of this type is shown by way of example in FIGS. 11 to 15.
• a conical elastic annular claw (72) In the rest state, in dynamic regime or not, and without action on the push-button, a conical elastic annular claw (72), thanks its arms (73) (for example 6 arms) each terminated by a shoulder (79) directed towards the axis (6), retains the tool (5) axially.
• the claw (72) is integral with the barrel pinion rotating by the engagement of the peripheral projections (74) of the claw in corresponding openings (76) made in the barrel pinion.
• a slot (77) completely crossing the claws allows the assembly and disassembly of the claw in the bore of the barrel pinion, giving it the necessary radial elasticity.
• the push button (55) is retained axially and centered by elastic blades (75) cut from its cap in the opening (27) of the head; these blades mounted under tension in the head body offer an elastic axial freedom (along axis 6) of the push button.
• Figures 12 and 13 show these blades (75) in the constrained position and show the clipping grooves (80) at the end of the blades for clipping the pusher (55) into the opening (27).
• the clamping-loosening means is the elastic conical claw (72) whose shoulders (79) are capable of engaging in the annular groove or groove (28) of the instrument, and the means for exerting the loosening forces and constituted by the conical interior shape (82) of said claw (72), the radial deformation of which is guaranteed by the slot (77).
• FIG. 8 is an axial section of FIG. 9 and which shows that the head has a cavity (83) provided around or next to the barrel of the pinion-barrel to contain a solid fat which is released at each use in small quantity by an orifice (84) of the wall (85) of separation between the cavity and the barrel in order to lubricate the barrel.
• the envelope (8) can be produced in a single piece by molding a plastic material (for example PEEK) and therefore electrically insulating or a sintered material comprising metallic inclusions (for example Metal Injection Molding for short MIM ) and conductor or any other material.
• a plastic material for example PEEK
• electrically insulating or a sintered material comprising metallic inclusions for example Metal Injection Molding for short MIM ) and conductor or any other material.
• This envelope includes: in the head, a first housing (26) for mounting a tool holder and an instrument along a drive axis (6) said housing opening on either side of the head through two openings, of which at least one, the opening (27) has dimensions suitable for allowing the introduction of all the organs of the head as well as their assembly, in the handle, a second housing (33) of rectilinear axis (7) opening on the one hand at the distal end of the handle by an opening (81) and opening on the other hand, at the end close to the head, in the first housing (26) by a lateral opening (32) allowing the cooperation between the mechanical parts of the head and those of the handle.
• the opening (81) is dimensioned so as to be able to allow the introduction of all the members of the handle as well as their mounting inside thereof, along a rectilinear axis called the axis of the handle (7 ).
• an envelope is provided, the axes (6) and (9) of which form, for example, an angle of between 90 and 180 °, preferably between 100 and 130 ° and to make a right handpiece on may provide that the axes (6) and (7) are parallel and offset so as to retain an opening (27) of the head for mounting the internal parts and fitting a plug of a push button.
• This concept is particularly advantageous because it makes it possible to: reduce the number of bearings, or even eliminate them, reduce the cost of the handpiece, reduce the dimensions of the handpiece facilitate cleaning (smoothed forms), improve hygiene (one piece so no interface).

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• Health & Medical Sciences (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Dentistry (AREA)
• Epidemiology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=34630225

Family Applications (1)

Country Status (6)

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Family Cites Families (3)

• 2003
  • 2003-11-25 FR FR0313900A patent/FR2863862B1/fr not_active Expired - Fee Related
• 2004
  • 2004-09-15 EP EP04787380A patent/EP1689311A1/fr not_active Withdrawn
  • 2004-09-15 BR BRPI0416917-4A patent/BRPI0416917A/pt not_active Application Discontinuation
  • 2004-09-15 CN CNA2004800301592A patent/CN101094620A/zh active Pending
  • 2004-09-15 WO PCT/FR2004/002334 patent/WO2005063141A1/fr not_active Application Discontinuation
  • 2004-09-15 KR KR1020067012759A patent/KR20060128897A/ko not_active Application Discontinuation

Non-Patent Citations (1)

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