The present invention discloses a non-invasive blood pressure measurement apparatus and a safety protection method. The ring gear and the revolving gear are divided into halves in the thickness direction. The ejector of the present invention is able to eject the external device engaged therewith. In addition, methods for treating alternating constipation-predominantdiarrhea-predominant irritable bowel syndrome are an alternative embodiment of the invention. A queue manager may be provided to keep the priority queue updated during LED drive operations based on operating conditions associated with the LED channels. The clamping bars are connected to a pneumatic cylinder or an electromechanical actuator through a series of links and an actuator wheel so that extension and retraction of the pneumatic cylinder or the electromechanical actuator causes the clamping bars to rotate and counter-rotate.