Spring adjusting means for control devices

Claim 1

APPARATUS FOR VARIABLY LOADING THE DIAPHRAGM OPERATOR OF A PRESSURE RESPONSIVE CONTROL DEVICE TO RENDER THE DEVICE ADJUSTABLE BETWEEN MAXIMUM AND MINIMUM OPERATING POINTS COMPRISING: A SPRING FOR LOADING THE DIAPHRAGM IN OPPOSITION TO THE PRESSURE; FORCE TRANSMITTING MEANS ENGAGEING ONE END OF SAID SPRING MEMBER AND ADAPTED TO TRANSMIT FORCE THEREFROM TO THE DIAPHRAGM; A MOTION TRANSMITTING MEMBER ROTATABLY MOUNTED ON THE BODY OF THE DEVICE; AN ARM MEMBER FIXED TO SAID MOTION TRANSMITTING MEMBER AND EXTENDING GENERALLY TRANSVERSELY THERETO; A SELECTOR MEMBER MOUNTED ON SAID MOTION TRANSMITTING MEMBER; MEANS ASSOCIATED WITH SAID SELECTOR MEMBER FOR LIMITING ANGULAR MOVEMENT THEREOF TO MOVEMENT BETWEEN TWO POSITIONS CORRESPONDING TO THE MAXIMUM AND MINIMUM OPERATING POINTS OF THE DEVICE; MEANS ASSOCIATED WITH SAID SELECTOR MEMBER FOR INDICATING THE OPERATING POINT OF THE CONTROL DEVICE; AND CALIBRATION MEANS FOR THE DEVICE INCLUDING MEANS FOR ADJUSTING THE ROTATIONAL POSITION OF SAID SELECTOR MEMBER ON SAID MOTION TRANSMITTING MEMBER AND FOR LOCKING SAID SELECTOR MEMBER TO SAID MOTION TRANSMITTING MEMBER THEREAFTER, AND A SPRING ENGAGING MEMBER MOUNTED ON SAID ARM MEMBER AND ADJUSTABLE ALONG THE AXIS THEREOF AND ENGAGING THE OTHER END OF SAID SPRING, SAID SPRING BEING SO CONSTRUCTED THAT SAID ARM MEMBER IS SUBSTANTIALLY PERPENDICULAR TO SAID SPRING AT THE MAXIMUM OPERATING POINT AND SO THAT SAID ARM MEMBER FORMS AN ACUTE ANGLE WITH SAID SPRING AT THE MINIMUM OPERATING POINT; SAID CALIBRATION MEANS AFFORDING CALIBRATION OF THE DEVICE BY FIRST ROTATING SAID MOTION TRANSMITTING MEMBER TO A POSITION WHERE THE LOADING ON THE DIAPHRAGM CAUSES THE DEVICE TO OPERATE AT THE MAXIMUM OPERATING POINT, BY ADJUSTING THE POSITION OF SAID SELECTOR MEMBER WITH RESPECT THERETO TO INDICATE THE MAXIMUM OPERATING POINT AND THEN BY LOCKING SAID SELECTOR MEMBER TO SAID MOTION TRANSMITTING MEMBER, BY ROTATING SAID SELECTOR MEMBER AND SAID MOTION TRANSMITTING MEMBER TO SAID MINIMUM PRESSURE POSITION, AND BY ADJUSTING SAID SPRING ENGAGING MEMBER ALONG THE AXIS OF SAID ARM MEMBER TO A POSITION WHERE THE LOADING OF THE DIAPHRAGM CAUSES THE DEVICE TO OPERATE AT THE MINIMUM OPERATING POINT.