Title (en)

BORING RAM

Publication

EP 0353400 A3 19910206 (DE)

Application

EP 89107906 A 19890502

Priority

DE 3825800 A 19880729

Abstract (en)

[origin: EP0353400A2] In a boring ram (1) having a percussion piston (3) displaceable in a tubular housing (2), and a displaceably mounted bit (10) which is passed through a housing tip (6), is guided with a collar (14) in a housing bore (13) having a front and a rear stop (20, 15) limiting the stroke (19) of the bit (10), and is provided with a stem (16) projecting into the working space (17) of the percussion piston (3), rebounding blows are avoided when the projecting length (18) of the stem (16) is less than the maximum stroke (19) of the collar (14) between the stops (15, 20). <IMAGE>

IPC 1-7

E21B 4/14; E21B 7/26

IPC 8 full level

E21B 7/26 (2006.01); E21B 4/14 (2006.01)

CPC (source: EP US)

E21B 4/145 (2013.01 - EP US); Y10T 279/17042 (2015.01 - EP US)

Citation (search report)

• [X] FR 2223143 A1 19741025 - FAVRE JACQUES [FR]
• [X] US 2181381 A 19391128 - ROBERTS JOHN J
• [X] US 1525471 A 19250210 - STEVENS EDWARD W
• [X] US 1481641 A 19240122 - JIMERSON FRANCIS A
• [X] US 2889811 A 19590609 - EMILE GUILLEMIER PIERRE LEON
• [XP] EP 0283734 A2 19880928 - ROMER HELMUTH
• [A] DE 3124524 A1 19830113 - JENNE GUSTAV
• [AD] DE 2157259 B1 19721109 - TRACTO TECHNIK [DE]
• [A] DE 2537176 B1 19761209 - JENNE & STRAHM AG [CH]

Designated contracting state (EPC)

BE CH FR GB IT LI NL

DOCDB simple family (publication)

EP 0353400 A2 19900207; EP 0353400 A3 19910206; EP 0353400 B1 19940316; DE 3825800 A1 19900201; DE 3825800 C2 19910829; JP 2693234 B2 19971224; JP H0247492 A 19900216; US 5095998 A 19920317

DOCDB simple family (application)

EP 89107906 A 19890502; DE 3825800 A 19880729; JP 16059589 A 19890622; US 55021090 A 19900706