Browse Prior Art Database

Magnetic Tape Reel Control Servo System

IP.com Disclosure Number: IPCOM000095702D
Original Publication Date: 1964-May-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Aweida, JE: AUTHOR [+3]

Abstract

This servo system automatically controls the upper and lower dynamic positions of tape loop 1 in vacuum column 2.

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Magnetic Tape Reel Control Servo System

This servo system automatically controls the upper and lower dynamic positions of tape loop 1 in vacuum column 2.

Oscillator 3 generates reference signal ER to be applied both to sensor 4, whose output signal is proportional to the position of loop 1, and to subtraction circuit 5. Placed between oscillator 3 and circuit 5 is loop centering impedance 6 serving to center loop 1 around the centric point of its path of movement. The second input to circuit 5 is output signal EX of sensor 4. Output signal EO of circuit 5 is obtained by subtraction of EX and ER.

If voltages EX and ER are alternating voltages, they can be converted to direct voltages prior to subtraction in circuit 5, so that the output signal EO switches polarity with respect to voltage ER. This occurs when the tape loop position moves above or below the center of column 2. On the other hand, EX and ER can be subtracted as alternating voltages within circuit 5, so that the phase of voltage EO shifts by 180 degrees when the tape loop moves above or below the center of column 2. Voltage EO is applied to network 7for forming an output EO +(MdEO/dt). This includes a component that is proportional to EO and another component that is proportional to the time derivative of EO, designated dEO/dt.

Network 7 is followed by an impedance adjustment 8. This controls the distance of the high and low loop positions from the center position of loop 1. Power amplifier 9 receives...