Screening apparatus with self-adjusting eccentric weight

Claim 1

A SCREENING APPARATUS COMPRISING, IN COMBINATION, A FIXED BASE FRAME, A MOVABLE SCREEN FRAME INCLUDING A SUBSTANTIALLY HORIZONTALLY DISPOSED SCREEN DISPOSED OVER AND IN VERTICALLY SPACED RELATION WITH RESPECT TO SAID BASE FRAME, MEANS EXTENDING BETWEEN THE BASE FRAME AND SCREEN FRAME FOR SUPPORTING THE LATTER FROM THE FORMER SO THAT IT IS FREE TO GYRATE IN A SUBSTANTIALLY HORIZONTAL PLANE AT DIFFERENT AMPLITUDES ABOUT A FIXED CENTER WHILE NORMALLY AND YIELDINGLY BIASING THE SAME TOWARD SUCH FIXED CENTER, AND MEANS FOR EFFECTING GYRATION OF SAID MOVABLE SCREEN FRAME IN THE HORIZONTAL PLANE THEREOF, SAID MEANS COMPRISING AN UPSTANDING ELONGATED RIGID ROTARY DRIVE SHAFT EXTENDING BETWEEN THE BASE FRAME AND THE SCREEN FRAME, MEANS SWIVELLY CONNECTING THE EXTREME LOWER END OF SAID DRIVE SHAFT TO THE BASE FRAME WHEREBY THE SHAFT IS CAPABLE OF LIMITED TILTING MOVEMENTS ABOUT ITS SWIVEL POINT, MEANS ROTATABLY JOURNALLING THE UPPER END OF THE DRIVE SHAFT IN SAID SCREEN FRAME WHEREBY LATERAL COMPONENTS OF DISPLACEMENT OF SAID UPPER END WILL BE TRANSMITTED TO THE SCREEN FRAME BODILY, SAID JOURNALLING MEANS COMPRISING A ROLLER BEARING HAVING INNER AND OUTER RACES, MEANS SECURING THE OUTER RACE TO SAID SCREEN FRAME, THE UPPER END OF SAID DRIVE SHAFT PROJECTING INTO THE INNER RACE, AND AN ELASTOMERIC SPACING SLEEVE INTERPOSED BETWEEN THE UPPER END OF THE SHAFT AND THE INNER RACE, SAID ELASTOMERIC SLEEVE ALLOWING FOR LIMITED RELATIVE ANGULAR AND VERTICAL LOST MOTION DISPLACEMENTS BETWEEN THE SHAFT AND THE SCREEN FRAME, AN ECCENTRIC WEIGHT FIXEDLY SECURED TO SAID SHAFT ADJACENT TO THE UPPER END THEREOF AND HAVING ITS CENTER OF MASS DISPLACED OUTWARDLY OF THE SHAFT AXIS SO THAT UPON ROTATION OF THE SHAFT THE UPPER END THEREOF WILL BE CONSTRAINED TO GYRATE UNDER THE INFLUENCE OF CENTRIFUGAL FORCES ACTING UPON SAID UPPER END, THEREBY TRANSMITTING GYRATIONAL EFFECTS TO THE SCREEN FRAME THROUGH SAID ELASTOMERIC SPACING SLEEVE, AND MEANS FOR APPLYING TORQUE TO THE EXTREME LOWER END OF SAID DRIVE SHAFT TO EFFECT ROTATION OF THE SAME.