Title (en)

Set of telescopic boring rods with automatic coupling racks designed to transmit axial forces in both directions and with blocking elements of contiguous rods.

Title (de)

Satz von teleskopischen Bohrstangen mit automatisch verbindenden Zahnstangen zur Übertragung von Axialkräften in beide Richtungen und mit Elementen zur Verriegelung von benachbarten Stangen.

Title (fr)

Ensemble de tiges de forage téléscopiques pourvues de crémaillère de raccord automatique permettant de transmettre des forces axiales dans les deux directions et comportant des éléments de blocage entre les tiges contigues.

Publication

EP 0335059 A1 19891004 (EN)

Application

EP 88830416 A 19881012

Priority

IT 4400988 A 19880325

Abstract (en)

The invention at reference concerns a set of telescopic boring rods with automatic coupling racks, designed to transmit axial forces in both directions and with blocking elements consisting of adjoining rods. It is possible to transmit the entire axial thrust due to the particular shape of the teeth on the racks applied to the rods, these teeth having some horizontal sections. The possibility of blocking one or more adjoining rods allows the set to be extracted without using other means, even if the cable breaks, and allows holes of a smaller diameter than the most exterior rod to be made.

IPC 1-7

E21B 17/07

IPC 8 full level

E21B 17/046 (2006.01); E21B 17/07 (2006.01)

CPC (source: EP US)

E21B 17/046 (2013.01 - EP US); E21B 17/07 (2013.01 - EP)

Citation (search report)

• [A] US 3447652 A 19690603 - TIPTON JOE D
• [A] US 3763666 A 19731009 - TIBUSSEK F
• [A] US 3255612 A 19660614 - MAYER JAMES R, et al
• [AP] DE 8714200 U1 19880310

Designated contracting state (EPC)

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

DOCDB simple family (publication)

EP 0335059 A1 19891004; IT 1220730 B 19900621; IT 8844009 A0 19880325

DOCDB simple family (application)

EP 88830416 A 19881012; IT 4400988 A 19880325