Borehole inclinometer

Claim 1

IMPROVED BORE HOLE INCLINOMETER ASSEMBLY ADAPTED FOR INSERTION IN A STRING OF DRILL PIPE ABOVE A DRILL BIT IN A BORE HOLE, COMPRISING: AN ELONGATED CASING MEMBER ATTACHABLE TO SAID DRILL STRING AND HAVING A TOP CENTRAL OPENING AND A BOTTOM CENTRAL OPENING COMMUNICATING WITH THE BORE OF THE DRILL STRING, AN UPPER BELLOWS CHAMBER POSITIONED WITHIN SAID CASING MEMBER, AN UPPER BELLOWS WITHIN SAID UPPER CHAMBER, A PISTON CHAMBER POSITIONED BELOW SAID UPPER BELLOWS CHAMBER, IN FLUID COMMUNICATION WITH THE INTERIOR OF SAID UPPER BELLOWS, A LOWER BELLOWS CHAMBER POSITIONED BELOW SAID POSITION CHAMBER, A LOWER BELLOWS POSITIONED WITHIN SAID LOWER BELLOWS CHAMBER WITH THE INTERIOR OF SAID LOWER BELLOWS IN FLUID COMMUNICATION WITH SAID PISTON CHAMBER, A PENDULUM SUSPENDED WITHIN SAID PISTON CHAMBER, A FIRST PISTON SLIDABLY POSITIONED WITHIN SAID PISTON CHAMBER ADAPTED TO MOVE INTO CONTACT WITH AND THEREBY LOCK SAID PENDULUM, A COMPASS MOUNTED WITHIN SAID PISTON CHAMBER, A SECOND PISTON SLIDABLY POSITIONED WITHIN SAID PISTON CHAMBER ADAPTED TO MOVE INTO CONTACT WITH AND THEREBY LOCK SAID COMPASS, A SPRING URGING AT LEAST ONE OF SAID PISTONS INTO LOCKING POSITION, FLUID FILLING SAID PISTON CHAMBER AND SAID BELLOWS, MEANS ESTABLISHING FLUID COMMUNICATION BETWEEN SAID UPPER BELLOWS CHAMBER AND SAID TOP CENTRAL OPENING, MEANS ESTABLISHING FLUID COMMUNICATION BETWEEN SAID LOWER BELLOWS CHAMBER AND SAID BOTTOM CENTRAL OPENING, AND A CHANNEL WITHIN SAID CASING CONNECTING SAID TOP CENTRAL OPENING WITH SAID BOTTOM CENTRAL OPENING, SAID CHANNEL BOTTOM CENTRAL OPENINGS, WHEREBY FLUID CIRCULATION THROUGH SAID DRILL STRING WILL EXERT A PRESSURE DIFFERENTIAL, COMMUNICABLE TO SAID PISTONS THROUGH SAID BELLOWS, SUFFICIENT TO MOVE SAID PISTONS OUT OF LOCKING POSITION AGAINST THE ACTION OF SAID SPRING.