Control valve for counterblow-tap hole-boring machine

US5044398A · kind A · utility

Assignee

• Bohler Pneumatik International Gesellschaft m.b.H. · AT

Inventors

• Franz Mock · Bruck an der Mur, AT
• Peter Pacnik · Leoben, AT
• Werner Schantl · Mitterdorf, AT
• Josef Mocivnik · Fohnsdorf, AT
• Hans-Jorg Muller-Spath · Kreuztal, DE

Key dates

• Filing date: Dec 20, 1989
• Grant date: Sep 3, 1991
• Expiry date: Dec 20, 2009

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T137/87241
• WIPO field: Civil engineering
• WIPO sector: Other fields

Abstract

A counterblow--tap hole--boring machine, especially for pneumatic rammer advance, combined with a counterblow device which serves as tapping equipment and a rotator for the actuation of a bar drill or a striking bar, consisting of sliding control valves which feed the main air to the consumer and back as exhaust, whereby an additional quick action ventilating valve quickly reduces the pressure of the used air, is provided with a mobile control piston (20) disposed on the distal end of the axially sliding control valve (15), which holds a valve disk (16) and controls the main air supply, between the housing (12) and the shaft of the sliding control valve (15), whereby a separate annular piston (18) alternatingly rests against the valve fitting surface (19) and a fitting surface (29) at the control piston (20).