PNEUMATIC SOURCE OF SEISMIC SIGNALS Russian patent published in 1994 - IPC

FIELD: mineral exploration. SUBSTANCE: source has rod 1 with top, middle, and bottom pistons 2, 3, and 4, respectively, moving within cylinder 23 in which the they form working chamber 24, control chamber 25, and damping chamber 28. Pistons 2 and 3 are provided with sealing assemblies 17 and 18 in the form of flexible rings fitted in annular drillings communicating with each other and with electropneumatic valve space 9. During operation compressed air is fed from space 9 to starting space 34 under external circular belt 28. Pressure drop within space 9 causes decrease in compressive force of flexible rings of assemblies 17, 18 applied to cylinder 23. The latter starts moving at high speed without friction upwards and brings working chamber 24 in communication with surrounding atmosphere. Sealing assemblies and design of damping chamber provide for reduction of friction force, wear of seals, elimination of spontaneous break. EFFECT: improved efficiency due to increased amplitude of seismic signal, enlarged service life due to reduced wear of seals and elimination of spontaneous break. 3 dwg