Impact apparatus for generating a sonic impulse employed in seismic geological exploration

Claim 1

IN APPARATUS FOR GENERATING A SONIC IMPULSE EMPLOYED IN SEISMIC GEOLOGICAL EXPLORATION: A MASSIVE COUPLING PLATE ELEMENT HAVING OPPOSED, GENERALLY FLAT MAJOR FACES, SAID ELEMENT BEING ADAPTED TO BE POSITIONED DURING USE THEREOF WITH ONE OF SAID FACES IN SUBSTANTIALLY FLAT ENGAGEMENT WITH THE EARTH AND ENTIRELY SUPPORTED THEREBY; A FRAME ASSEMBLY ON SAID ELEMENT AND PROVIDED WITH A MEMBER IN OVERLYING RELATIONSHIP TO SAID ELEMENT; A MASSIVE HAMMER RECIPROCABLE VERTICALLY IN SAID ASSEMBLY BETWEEN THE ELEMENT AND SAID MEMBER AND DISPOSED TO IMPACTIVELY ENGAGE THE OTHER FACE OF SAID ELEMENT; A LARGE, UPRIGHT COIL SPRING HAVING A VERTICAL CENTRAL AXIS DEFINING ITS LINE OF ACTION AND A PAIR OF OPPOSED, UPPER AND LOWER ENDS, SAID SPRING BEING DISPOSED BETWEEN SAID HAMMER AND SAID MEMBER WITH THE LOWER AND UPPER ENDS THEREOF ENGAGING THE HAMMER AND THE MEMBER RESPECTIVELY; STRUCTURE CARRIED BY SAID ASSEMBLY AND ENGAGEABLE WITH SAID HAMMER FOR SHIFTING THE LATTER VERTICALLY UPWARDLY ALONG SAID AXIS IN DIRECT OPPOSITION TO THE LINE OF ACTION OF SAID SPRING TO THEREBY EFFECT SUBSTANTIAL COMPRESSION THEREOF, AND FOR RELEASABLY MAINTAINING SAID HAMMER SPACED FROM SAID ELEMENT UNDER THE FORCE OF THE COMPRESSED SPRING; AND MEANS ON SID ASSEMBLY AND OPERABLY COUPLED TO SAID STRUCTURE FOR INSTANTANEOUSLY RELEASING THE HAMMER FROM SAID STRUCTURE FOR SUBSTANTIALLY FRICTIONLESS MOVEMENT OF THE HAMMER TOWARD SAID ELEMENT FREE FROM SAID STRUCTURE ALONG A DOWNWARD VERTICAL PATH EXTENDING AXIALLY OF THE SPRING, WHEREBY THE HAMMER IS ACCELERATEDLY DRIVEN BY THE SPRING INTO IMPACTIVE ENGAGEMENT WITH THE ELEMENT TO GENERATE A SINGLE RECORDABLE SONIC IMPULSE IN THE EARTH.