초록 ▼

Self-tapping screw for small-bone surgery, includes a threaded proximal head (2), a threaded distal shank with greater pitch and an internal cannula (4), characterized in that the distal shank (3) is threaded over its entire length in that the end of the shank has, apart from milled portions forming

Self-tapping screw for small-bone surgery, includes a threaded proximal head (2), a threaded distal shank with greater pitch and an internal cannula (4), characterized in that the distal shank (3) is threaded over its entire length in that the end of the shank has, apart from milled portions forming self-tapping faces on the first distal threads, at least two milled faces and which with the cannula, determine at least two notches (11), and at least two self-boring edges at the distal end of the screw, and in that the thread of the head has, aside from milled portions forming self-tapping faces on the first threads of the proximal screw thread, chamfered faces (16-19), determining boring edges (12b-15b) preceded by a short groove.

대표청구항 ▼

The invention claimed is: 1. Self-tapping screw for small-bone surgery, particularly of the Barouk screw type, comprising: a threaded proximal head (2) with a screw thread; a threaded distal shank (3) with a screw thread, the pitch of the screw thread on the proximal head being shorter than the p

The invention claimed is: 1. Self-tapping screw for small-bone surgery, particularly of the Barouk screw type, comprising: a threaded proximal head (2) with a screw thread; a threaded distal shank (3) with a screw thread, the pitch of the screw thread on the proximal head being shorter than the pitch of the screw thread of the distal shank; and an internal passage (4) in the manner of a cannula, the distal shank (3) threaded over its entire length to meet the threaded head (2), the distal end of the distal shank having milled portions forming angularly equidistant self-tapping faces (5, 5 a, 6, 6a) on first distal threads terminating portions of the screw thread of the distal shank, apart from the milled portions, at least two milled portions forming angularly equidistant faces (9, 10) about the longitudinal axis of the screw that together with the internal passage determine at least two notches (11) in the terminal end of the internal passage, at least two self-boring cutting edges (5b, 6b) at the distal end of the screw, the distal end of the screw thread of the head having first milled portions forming angularly equidistant self-tapping faces ( 12 to 15, 12a to 15a) on first threads of the proximal screw thread, aside the first milled portions, second milled portions forming angularly equidistant chamfered faces (16-19), the second milled portions determining boring edges (12b- 15b); and a short groove (2b) preceding the boring edges and following the screw thread of the distal shank. 2. Screw according to claim 1, characterized, in that the milled portions forming angularly equidistant self-tapping faces (5, 6) are preceded by the milled portions (9, 10) determining the notches (11) and also forming respectively common perpendicular faces (5a, 6a), and in that angularly offset milled portions (7, 8) determine, with said perpendicular faces (5a, 6 a) said cutting edges (5b, 6b). 3. Screw according to claim 1, characterized by dimensions which lie in the following ranges: screw length: 10 mm to 60 mm head length 5-10 mm pitch of distal screw thread: between 1 and 3 mm pitch of proximal screw thread: between 0.8 and 2.5 mm diameter of the distal part (crest of thread): 2.5 to 5 mm. 4. Set of several screws according to claim 1, having different dimensions. 5. Set according to claim 4, characterized in that it contains a number of screws of different lengths, but having the same characteristics in terms of diameter and therefore diametral size and self-boring and self-tapping ability. 6. Self-tapping screw for small-bone surgery, particularly of the Barouk screw type, comprising: a threaded proximal head (2) and a threaded distal shank (3), the pitch of the screw thread on the proximal head being shorter than the pitch of the screw thread on the distal shank, and an internal passage (4) in the manner of a cannula, wherein, the distal shank (3) is threaded over its entire length to meet the threaded head (2), the distal end of the distal shank has milled portions forming angularly equidistant self-tapping faces (5, 5 a, 6, 6a) on first distal threads, at least two milled portions, preceding said self-tapping faces (5, 5a, 6, 6a) and forming angularly equidistant faces (9, 10) about the longitudinal axis of the screw and having respectively common perpendicular faces (5a, 6a) with the taping faces that with the internal passage, determine at least two notches ( 11) in the end of the internal passage, and angularly offset milled portions (7, 8) determine with said perpendicular faces (5a, 6 a) at least two self-boring cutting edges (5b, 6 b) at the distal end of the screw, and milled portions at the distal end of the screw thread of the head, and located aside from milled portions forming angularly equidistant self-tapping faces (12 to 15, 12a to 15a) on first threads of the proximal screw thread, form angularly equidistant chamfered faces (16-19), the chamfered faces determining boring edges (12b-15 b), and the milled portions are preceded by a short groove (2 b) which follows the distal screw thread. 7. Screw according to claim 6 characterized by dimensions which lie in the following ranges: screw length: 10 mm to 60 mm head length 5-10 mm pitch of distal screw thread: between 1 and 3 mm pitch of proximal screw thread: between 0.8 and 2.5 mm diameter of the distal part (crest of thread): 2.5 to 5 mm. 8. Set of several screws according to claim 6, having different dimensions. 9. Set according to claim 8, characterized in that it contains a number of screws of different lengths, but having the same characteristics in terms of diameter and therefore diametral size and self-boring and self-tapping ability. 10. A self-tapping surgery screw, comprising: a threaded proximal head (2); a threaded distal shank (3), the shank threaded over the entire overall length thereof; a relief groove (2b) directly connecting the head to the shank, a maximum diameter of the relief groove being less than a maximum diameter of the shank; an axial canal (4) formed throughout the entire overall length of the head, relief groove, and the shank; a socket (20) in the head, the socket shaped to take a screwing tool end; a first self-boring part located at the terminal end of the shank and including at least two self-boring cutting edges (5 b, 6b) at the distal end of the shank, and at least two milled portions forming angularly equidistant faces (9, 10) about the longitudinal axis of the shank that together with the axial canal define at least two notches (11) in the terminal end of the axial canal; and a second self-boring part located at an end of the head adjacent the relief groove and opening to the relief groove. 11. The screw of claim 10, wherein, the distal end of screw threads of the head have first milled portions forming angularly equidistant self-tapping faces (12 to 15, 12a to 15a) on the screw threads of the thread, and aside the first milled portions, second milled portions form angularly equidistant chamfered faces (16-19), the second milled portions determining boring edges (12b-15 b) of the second self-boring part. 12. The screw of claim 10, wherein, the shank is a longer distal part of the screw and has a cylindrical, first screw thread of a first pitch, and the head has a second screw thread of larger diameter, as compared to the first screw thread, and a second pitch shorter than the first pitch. 13. The screw of claim 12, wherein, screw threads facing towards the distal end have anterior flanks inclined forward and have posterior flanks practically perpendicular to the axis of the screw. 14. The screw of claim 13, wherein the screw threads of the head have anterior flanks inclined forward and have posterior flanks practically perpendicular to the axis of the screw. 15. The screw of claim 10, wherein, the second self-boring part has an initial conical part of a first inclination (γ) narrowing toward the relief groove (2 b), a self-tapping end, and four milled portions angularly offset by 90째 defining four faces (12, 13, 14, 15) with perpendicular tapping faces (12a, 13a, 14a, 5a) supplemented by four flat milled portions of a second inclination (δ) with respect to the axis of the screw.