Chair control for tilting and swivel chairs having improved tensioning bolt

Claim 1

IN A CHAIR CONTROL FOR A TILTING CHAIR HAVING A BASE, A CHAIR SUPPORT MEMBER, A FIXED FRAME CARRIED BY THE MEMBER, A SECOND FRAME PIVOTALLY MOUNTED ON THE FIXED FRAME FOR LIMITED PIVOTAL MOVEMENT ABOUT A HORIZONTAL AXIS RELATIVE TO THE FIXED FRAME, SAID SECOND FRAME HAVING MEANS FOR ATTACHING IT TO A CHAIR SEAT, AND BIASING MEANS YIELDABLY CONNECTING THE FIXED FRAME AND THE SECOND FRAME AND URGING SAID SECOND FRAME TO A STOP POSITION RELATIVE TO THE FIXED FRAME AND YIELDABLY RESISTING PIVOTAL MOVEMENT OF THE SECOND FRAME AWAY FROM SAID STOP POSTION UNDER A FORCE APPLIED BY AN OCCUPANT OF THE CHAIR, SAID BIASING MEANS COMPRISING (A) A SUBSTANTIALLY RIGID CONNECTING MEMBER DISPOSED IN A HORIZONTAL PLANE TRANSVERSE TO SAID HORIZONTAL AXIS, (B) SAID CONNECTING MEMBER HAVING AT ONE END AN INTEGRALLY FORMED HEAD SEATED IN AN OPEN SLOT FORMED IN SAID FIXED MEMBER, SAID SLOT HAVING RETAINING SHOULDERS, (C) A FIXED PRESSURE PLATE SECURED TO THE SECOND FRAME AND HAVING AN OPENING THROUGH WHICH SAID CONNECTING MEMBER EXTENDS, (D) A SPRING SURROUNDING SAID CONNECTING MEMBER HAVING ONE END SEATED ON THE PRESSURE PLATE AND THE OTHER END RESTRAINED BY A TENSION ADJUSTING WHEEL MOUNTED ON THE OTHER END OF THE CONNECTING MEMBER.