Global Patent Index - EP 0408517 A3

EP 0408517 A3 19910605 - CONTROL DEVICE FOR SLIDE VALVES IN OIL-OPERATED HAMMERS

Title (en)

CONTROL DEVICE FOR SLIDE VALVES IN OIL-OPERATED HAMMERS

Publication

EP 0408517 A3 19910605 (EN)

Application

EP 90830180 A 19900427

Priority

IT 2117789 A 19890714

Abstract (en)

[origin: EP0408517A2] In an oil-operated hammer (2) the movement of the striking mass (9) is controlled by a distributor (24) guided within a valve body (15) provided with delivery ports (16) to which oil under pressure is send and exhaust ports (17) communicating with the oil exhaust circuit. The distributor (24) is movable from an opened position in which the delivery ports (16) are uncovered to allow the entrance of oil under pressure thrusting the striking mass (9) towards a striking position, to a closed position in which the exhaust ports (17) are uncovered to let the oil outflow during the displacement of the mass (9) to the return position. The starting displacement of the distributor (24) to the opened position is caused by the pumping produced by the striking mass (9) as a result of the exhaust ports (17) being covered by the striking mass itself when the latter is about to reach its return position.

IPC 1-7

B25D 9/20

IPC 8 full level

B25D 9/14 (2006.01)

CPC (source: EP)

B25D 9/145 (2013.01)

Citation (search report)

Designated contracting state (EPC)

BE DE DK ES FR GB GR LU NL

DOCDB simple family (publication)

EP 0408517 A2 19910116; EP 0408517 A3 19910605; IT 1230342 B 19911018; IT 8921177 A0 19890714

DOCDB simple family (application)

EP 90830180 A 19900427; IT 2117789 A 19890714