Dental high-speed contra-angle for processing hard materials in the oral cavity of a patient

Abstract

A dental high-speed contra-angle handpiece (1) for processing hard materials in the oral cavity of a patient, comprising: an outer sleeve (2) delimiting the dental high-speed contra-angle handpiece (1) from the environment, said outer sleeve having a handle portion (2A) extending along a longitudinal axis (3) and a head portion (2B) extending along a rotational axis (4), wherein the longitudinal axis (3) and the rotational axis (4) are arranged at an angle other than 0° to one another; a holding device (5) arranged in the head portion (2B) for holding a processing tool (6) such that it can rotate about the rotational axis (4); a tool receiving opening (7) for inserting and releasing the processing tool (6) into the holding device (5); a mechanical drive device (8) for rotating the holding device (5) to an idle speed of at least 140,000 rpm; and a spring element (25) preloaded and displaceable along the rotational axis (4). Actuator (19),which is operatively connectable to the holding device (5) in order to selectively move the holding device (5) from a first position, in which the machining tool (6) is fixed in the holding device (5), to a second position, in which the machining tool (6) can be inserted into or removed from the holding device (5), characterized in that the holding device (5) comprises: a drive sleeve (9) for releasably receiving a shaft (6A) of the machining tool (6), wherein the drive sleeve (9) has an outer wall (9A) in which a plurality of through-bores (10) are provided, and the outer wall (9A) surrounds a cylindrical interior (11) in which the shaft (6A) of the machining tool (6) can be received, a plurality of holding bodies (12) movable radially to the axis of rotation (4), wherein a holding body (12) can be received in each of the through-bores (10) of the drive sleeve (9),a clamping sleeve (13) which is displaceable along the rotational axis (4) and has a clamping sleeve wall (13A) which surrounds the holding bodies (12) and at least the section of the drive sleeve (9) having the through-bores (10), wherein by displacing the clamping sleeve (13) along the rotational axis (4), the holding bodies (12) are movable radially with respect to the rotational axis (4) and the clamping sleeve (13) and / or the holding bodies (12) selectively assume the first position and the second position, wherein in the first position the holding bodies (12) are pressed by the clamping sleeve (13) into the through-bores (10) of the drive sleeve (9) in such a way that sections of the holding bodies (12) protrude into the cylindrical interior (11) of the drive sleeve (9), whereby the shank (6A) of the machining tool (6) is fixed in the cylindrical interior (11) of the drive sleeve (9), and in the second position the Clamping sleeve (13) surrounds the holding body (12) with play,so that the holding bodies (12) can be moved radially away from the axis of rotation (4), whereby the shaft (6A) of the machining tool (6) can be inserted into or removed from the drive sleeve (9).

Claims

[1] Dental high-speed contra-angle (1) for processing hard materials in the oral cavity of a patient, comprising: an outer sleeve (2) delimiting the dental high-speed contra-angle (1) from the environment, with a handle section (2A) extending along a longitudinal axis (3) and a head section (2B) extending along a rotational axis (4), wherein the longitudinal axis (3) and the rotational axis (4) are arranged at an angle other than 0° to one another, a holding device (5) arranged in the head section (2B) so as to be rotatable about the axis of rotation (4) for holding a machining tool (6), a tool receiving opening (7) for inserting and releasing the machining tool (6) into the holding device (5), a mechanical drive device (8) for rotating the holding device (5) to an idle speed of at least 140,000 rpm, and an adjusting element (19) pre-tensioned by a spring element (25) and displaceable along the rotational axis (4), which is operatively connectable to the holding device (5) in order to selectively move the holding device (5) from a first position in which the machining tool (6) is fixed in the holding device (5) to a second position in which the machining tool (6) can be inserted into or removed from the holding device (5), characterized by , that the holding device (5) comprises: a drive sleeve (9) for releasably receiving a shaft (6A) of the machining tool (6), wherein the drive sleeve (9) has an outer wall (9A) in which a plurality of through holes (10) are provided, and the outer wall (9A) surrounds a cylindrical interior (11) in which the shaft (6A) of the machining tool (6) can be received, a plurality of holding bodies (12) which are movable radially to the axis of rotation (4), wherein in each case one holding body (12) can be received in one of the through holes (10) of the drive sleeve (9), a clamping sleeve (13) displaceable along the rotational axis (4) with a clamping sleeve wall (13A) which surrounds the holding bodies (12) and at least the section of the drive sleeve (9) having the through holes (10), wherein by displacing the clamping sleeve (13) along the rotational axis (4), the holding bodies (12) are radially movable with respect to the rotational axis (4) and the clamping sleeve (13) and / or the holding bodies (12) selectively assume the first position and the second position, wherein in the first position the holding bodies (12) are pressed by the clamping sleeve (13) into the through-bores (10) of the drive sleeve (9) in such a way that sections of the holding bodies (12) protrude into the cylindrical interior (11) of the drive sleeve (9), whereby the shank (6A) of the machining tool (6) is fixed in the cylindrical interior (11) of the drive sleeve (9), and in the second position the clamping sleeve (13) surrounds the holding bodies (12) with play, so that the holding bodies (12) are radially movable away from the rotational axis (4), whereby the shank (6A) of the machining tool (6) is inserted into the drive sleeve (9) can be inserted into or removed from the device. [2] Dental high-speed contra-angle (1) for machining hard materials according to claim 1, characterized by that the drive sleeve (9) extends to the tool holder opening (7). [3] Dental high-speed contra-angle (1) for machining hard materials according to claim 1 or 2, characterized by that the drive sleeve (9) has a shoulder (26) on its outer circumference, on which a spring element (20) is mounted, which prestresses the clamping sleeve (13), wherein the outer wall (9A) of the drive sleeve (9) has a first section (9A-1) with a first wall thickness and a second section (9A-2) with a second wall thickness, wherein the first wall thickness and the second wall thickness have different values, and the shoulder (26) is formed where the first section (9A-1) adjoins the second section (9A-2). [4] Dental high-speed contra-angle (1) for machining hard materials according to claim 3, characterized byin that the drive sleeve (9) has a length (L) which extends from a first end face (27) surrounded by the clamping sleeve (13) to a second end face (28) at the tool receiving opening (7), wherein the shoulder (26) is formed in a section of the drive sleeve (9) which extends from the first end face (9A-1) to half the length (L). [5] Dental high-speed contra-angle (1) for machining hard materials according to claim 3 or 4, characterized by an output gear element (29) which is arranged centrally around the axis of rotation (4) of the holding device (5), wherein the shoulder (26) is arranged between the output gear element (29) and the first end face (27). [6] Dental high-speed contra-angle (1) for machining hard materials according to claim 3, 4 or 5, characterized bya drive gear element (30) arranged in the head section (2B) and rotating about an axis arranged at an angle other than 0° to the axis of rotation (4), wherein the shoulder (26) is arranged within an outer diameter (D) of the drive gear element (30). [7] Dental high-speed contra-angle (1) for machining hard materials according to one of the preceding claims, characterized by that the holding device (5) has a gear sleeve (31) on which the output gear element (29) arranged centrally around the axis of rotation (4) of the holding device (5) is provided, wherein the drive sleeve (9) is received in the gear sleeve (31) in a rotationally fixed manner. [8] Dental high-speed contra-angle (1) for machining hard materials according to claim 7, characterized by that the clamping sleeve (13) and / or the spring element (20) prestressing the clamping sleeve (13) and / or the holding bodies (12) are further accommodated in the gear sleeve (31). [9] Dental high-speed contra-angle (1) for machining hard materials according to claim 7 or 8, characterized by that the gear sleeve (31) has a constant inner diameter over its entire length. [10] Dental high-speed contra-angle (1) for machining hard materials according to one of claims 7-9, characterized by that the holding device (5) is rotatably mounted in the head section (2B) by a first rolling bearing (32) and second rolling bearing (33), wherein the gear sleeve (31) forms a one-piece bearing body for the first and second rolling bearings (32, 33). [11] Dental high-speed contra-angle (1) for machining hard materials according to claim 10, characterized by that a first and second bearing seat (34, 35) for the first and second rolling bearings (32, 33) is provided on the outer circumference of the gear sleeve (31). [12] Dental high-speed contra-angle (1) for machining hard materials according to claim 11, characterized bythat the first and second rolling bearings (32, 33) are pressed directly onto the respective bearing seat (34, 35) on the outer circumference of the gear sleeve (31). [13] Dental high-speed contra-angle (1) for machining hard materials according to one of the preceding claims, characterized by on an inner side (13B) of the clamping sleeve wall (13A) at least one groove (14) extending axially with respect to the axis of rotation (4) is provided, in which one of the holding bodies (12) is received and can be guided. [14] Dental high-speed contra-angle (1) for machining hard materials according to claim 13, characterized by that the at least one groove (14) is formed as a recess (14A) in the inner side (13B) of the clamping sleeve wall (13A). [15] Dental high-speed contra-angle (1) for machining hard materials according to claim 13 or 14, characterized bythat the distance (A) between the axis of rotation (4) and an apex (15) of the concavely shaped recess (14A) is constant at least over a section of the at least one groove (14). [16] Dental high-speed contra-angle (1) for machining hard materials according to one of claims 13-15, characterized by that the at least one groove (14) opens into a recess (16) provided on the inner side (13B) of the clamping sleeve wall (13A), which is arranged such that the holding bodies (12) can be received therein. [17] Dental high-speed contra-angle (1) for machining hard materials according to claim 16, characterized by that at the end of the at least one groove (14) which is remote from the recess (16), an annular shoulder (17) is provided which runs around the inside (13B) of the clamping sleeve wall (13A). [18] Dental high-speed contra-angle (1) for machining hard materials according to claim 16 or 17, characterized byin that the clamping sleeve (13) has an extension (18) which extends in the direction of an adjusting element (19) of the dental angle piece (1) in order to displace the clamping sleeve (13) along the axis of rotation (4), wherein the recess (16) is arranged between the extension (18) and the at least one groove (14). [19] Dental high-speed contra-angle (1) for machining hard materials according to one of the preceding claims, characterized by that the clamping sleeve (13) is pre-tensioned by a spring element (20) surrounding the drive sleeve (9). [20] Dental high-speed contra-angle (1) for machining hard materials according to one of the preceding claims, characterized by an anti-rotation device (21) which prevents rotation of the clamping sleeve (13) about the rotation axis (4) and relative to the drive sleeve (9). [21] Dental high-speed contra-angle (1) for machining hard materials according to claim 20, characterized bythat the anti-twist device (21) has interlocking shaped elements (22, 23) which are provided at one end of the drive sleeve (9), which is received in the clamping sleeve (13), and at the clamping sleeve (13). [22] Dental high-speed contra-angle (1) for machining hard materials according to claim 21, characterized by that the shaped elements (22, 23) engage with one another when the clamping sleeve (13) is displaced in the direction of the tool receiving opening (7) of the holding device (5) and / or when the clamping sleeve (13) assumes the second position. [23] Dental high-speed contra-angle (1) for machining hard materials according to claim 21 or 22, characterized by that the shaped elements (22, 23) comprise a tab-like extension (22) on the outer wall (9A) of the drive sleeve (9) and a receptacle (23) for the tab-like extension (22) on the clamping sleeve (13). [24] Dental high-speed contra-angle (1) for machining hard materials according to one of the preceding claims, characterized by that the holding bodies (12) comprise ceramic material. [25] Dental high-speed contra-angle (1) for machining hard materials according to one of the preceding claims, characterized by that the drive sleeve (9) has a bushing (24) made of hard metal at the end which is arranged at the tool receiving opening (7) or is hardened by a hardening process.

Images