High pressure pistol for installation of hydraulic pit props - has central control sleeve with series of radial control holes forming bore crown

摘要

Pistol in which the thrusting end (44) of the plunger (23) on the sealing pin (30) or the lower end of the sealing pin itself is formed as a control sleeve (45). The control sleeve has control bores (46 47) arranged at a distance from the sealing seat (31) of the sealing pin and the outlet bore (25) of the prop valve (4). The radial control bores may be made as radial bores to form a bore crown (48 49). A further bore crown, or several bore crowns, are provided as far as the lower bore crown in the direction of the outlet bores (25), and the control bores are displaced in relation to one another.