Abstract A tape recording and playback device in which the recording tape is moved from a supply reel to a takeup reel at a constant tape speed and where the tape is driven by a drive motor coupled directly to the tape takeup reel. The tape speed is kept constant by a prerecorded control signal on the recording tape which is fed to the motor through a control or servoamplifier. The automatic adjustment of the takeup reel speed to provide a constant tape speed eliminates additional tape drive rollers or capstans and permits the tape to be run in either direction between the reels when a second motor is connected to the tape supply reel. When the system is driving a tape in the forward direction, the takeup reel motor supplies the power using the control system and the supply reel motor is used as a dynamic brake. When the tape is running in the opposite direction, the functions of the motors are reversed.
A drive system for moving a recording tape at a constant speed in either of two directions between two tape-carrying spools comprising: a. a first motor coupled to a first of said spools to drive said first spool in a first direction; b. a second motor coupled to the second of said spools to drive said second spool in a second direction; c. a coded signal recorded on and having a constant wavelength with respect to said recording tape; d. pickup means for sensing said coded signal; e. processing means coupled to said pickup means for generating a control voltage proportional to the frequency of the coded signal as sensed by the pickup means; f. means for supplying a reference voltage; g. means for comparing said control voltage and said reference voltage to provide a correction voltage; h. variable power means controlled by said correction voltage and selectively connectable to either of said first or second motor to supply power to the connected motor of such values as to produce movement of the tape at a constant speed; and i. means coupled between the processing means and the variable power means for sensing any absence of the coded signal and for generating a fail-safe voltage during such absence to further control the variable power means.
Claim 2
Dependent Claim
215 words
A drive system for moving a recording tape at a constant speed in either of two directions between two tape-carrying spools comprising: a. a first motor coupled to a first of said spools to drive said first spool in a first direction; b. a second motor coupled to the second of said spools to drive said second spool in a second direction; c. a coded signal recorded on and having a constant wavelength with respect to said recording tape; d. pickup means for sensing said coded signal; e. processing means coupled to said pickup means for generating a control voltage proportional to the frequency of the coded signal as sensed by the pickup means; f. means for supplying a reference voltage; g. means for comparing said control voltage and said reference voltage to provide a correction voltage; h. variable power means controlled by said correction voltage and selectively connectable to either of said first or second motor to supply power to the connected motor of such values as to produce movement of the tape at a constant speed; and i. means coupled between the processing means and the variable power means for sensing any absence of the coded signal and for generating a fail-safe voltage during such absence to further control the variable power means.