Pinch roller drive engagement mechanism for a communications monitor and

Abstract

The communications monitor and logger preferably uses reel-to-reel tape recorders to continuously record communications over multiple channels such as multiple telephone lines. Each tape recorder uses a pair of capstans and pinch rollers to move the tape during recording and play-back. The pinch rollers are engaged with the capstans by means of a solenoid through a linkage and spring coupling. The spring is stretched by the solenoid only after the pinch roller makes contact with the capstan, thus reducing the force required from the solenoid. The spring is pre-loaded so as to improve the accuracy with which the force applied to the pinch roller is determined. The solenoid is used to apply force to the spring only when the solenoid plunger approaches its seat, so as to make the most efficient use of the solenoid and minimize its size and electrical power usage. Individually adjustable brakes are provided for each of two tape reels, thus permitting individual adjustments to compensate for different characteristics of the brakes. The interior of the cabinet for the monitor and logger unit preferably is maintained at a pressure above ambient by a blower in order to keep out contaminants and reduce drop-outs. Air filters and sound-insulation are used for the dual purpose of keeping contaminants out and reducing noise emissions from the blower.