EP 0288780 A3 19900613 - EXTRUSION TOOL FOR MAKING A DRILL BLANK WITH AT LEAST ONE INTERNAL HELICAL FLUSH BORE

Title (en)

EXTRUSION TOOL FOR MAKING A DRILL BLANK WITH AT LEAST ONE INTERNAL HELICAL FLUSH BORE

Publication

EP 0288780 A3 19900613 (DE)

Application

EP 88105349 A 19880402

Priority

DE 3714479 A 19870430

Abstract (en)

[origin: US4831859A] An extrusion tool for making a drill bit blank provided with an internal rinsing bore extending helically in a longitudinal direction of the drill bit blank, includes a nozzle having an inner wall defining a throughgoing axial bore through which a malleable material is passed in a direction of extrusion parallel to the tool axis. The axial bore forms an inlet portion and a mold chamber adjoining the inlet portion downstream thereof as viewed in the direction of extrusion. There is further provided a mandrel situated in the inlet portion; a resiliently deformable wire supported by the mandrel and projecting into the mold chamber; and a helical device provided on the inner wall in the mold chamber for twisting the malleable material as it passes through the mold chamber. There is further provided a clamping device having a tightened state for immobilizing the nozzle and the mandrel with respect to one another during extrusion operation. In the loosened state of the clamping device a positional adjustment of the nozzle with respect to the mandrel may be made.

IPC 1-7

B21C 23/14; B21C 25/00; E21B 10/60

IPC 8 full level

B21C 23/10 (2006.01); B21C 23/14 (2006.01); B21C 25/00 (2006.01); B21C 25/02 (2006.01); B21C 25/04 (2006.01); E21B 10/60 (2006.01); E21B 10/61 (2006.01)

CPC (source: EP US)

B21C 23/10 (2013.01 - EP US); B21C 23/147 (2013.01 - EP US); B21C 25/00 (2013.01 - EP US); E21B 10/61 (2013.01 - EP US)

Citation (search report)

[AD] DE 8536805 U1 19860821
[A] US 2954121 A 19600927 - BENSON DONALD O
[A] US 3605475 A 19710920 - EAKIN GERALD R, et al
[A] US 2422994 A 19470624 - TAYLOR GEORGE F
[A] US 4059031 A 19771122 - ERDELYI FRANK F

Designated contracting state (EPC)

AT BE CH ES FR GB GR IT LI LU NL SE

DOCDB simple family (publication)

EP 0288780 A2 19881102; EP 0288780 A3 19900613; EP 0288780 B1 19911127; AT E69744 T1 19911215; DE 3714479 A1 19881117; DE 3714479 C2 19890615; DE 8717444 U1 19890112; JP H0450085 B2 19920813; JP S63278612 A 19881116; US 4831859 A 19890523

DOCDB simple family (application)

EP 88105349 A 19880402; AT 88105349 T 19880402; DE 3714479 A 19870430; DE 8717444 U 19870430; JP 10151888 A 19880426; US 18907788 A 19880502