| 摘要 |
An air cannon is used for removing adhering and accumulating bulk material in silos, heat exchangers, lines and the like with the aid of blasts of air. The necessary compressed air is stored in a pressure container and passes, via the outlet valve 3 and a discharge nozzle 11 adjoining the latter, into the region of the adhering bulk material and detaches the latter. The outlet valve 3 has a valve housing 9 and a piston 19 which is guided longitudinally in a guide 18 and is acted upon, at the rear, by a closing pressure which can be lowered abruptly. The piston 19 has, at its front side facing the discharge nozzle 11, an annular valve sealing surface 25, inside which, when the valve is closed, the pressure in the discharge nozzle 11 acts and outside which the pressure prevailing in the pressure container acts. In order, in the case of a simple construction of the air cannon, to produce a blast of air having a high momentum, an annular channel 17 which is connected to the pressure container is constructed between the valve housing 9 and the guide 18 for the piston 19. When the valve is open, the annular channel 17 opens, in the form of an entirely cylindrical opening 39, into the discharge nozzle 11. <IMAGE> |
