SU1229815A1 - Device for controlling transportation speed of magnetic tape - Google Patents

Abstract

This invention relates to a magnetic recording technique. The purpose of the invention is to reduce the control error. Pulses from the output of the sensor 9 angular velocity, the frequency of which is proportional to the angular velocity of the gate, feed, its node 2, in the form of allowing the start of the counting go to counter 10, the second input of which receives pulses from the output of the generator 11 standard pulses. The number of pulses received from the standard pulse generator for the period between two consecutive angular velocity sensor pulses, counter 10 converts to a binary code, which until the next pulse arrives is stored in memory register 12, at the output of which a signal is generated in binary code that is directly proportional to the period or inversely proportional to the angular velocity of rotation of the feed unit. At the input, the current speed of the multiplying digital-to-analog converter (DAC) 13 is generated depending on the deflection signal of the current speed of the magnetic tape (ML) 15. An analog signal from the output of the multiplying DAC controls the moment of the feeding node 2, which leads to establishing the required value of the tension of the ML . 1 il. S ISD tc with 00 pr

Description

The invention relates to a magnetic recording technique, namely, devices for controlling the speed of stirring, magnetic tape.

The purpose of the invention is to reduce the control error.

The drawing shows a block diagram of the device.

The device contains receiving and supplying nodes 1 and 2, a linear speed frequency sensor 3, a deflection driver 4, an analog converter containing a limiting amplifier 5, a frequency detector 6, an operational amplifier 7, a filter 8, a frequency sensor 9 of angular speed of rotation, a counter 10, a standard pulse generator 11, a memory register 12, multiplying a digital-to-analog converter 13, racks 14, a magnetic tape.

The device works as follows.

When the speed of movement of the magnetic tape deviates from its average value, the frequency-modulated signal at the output of the deflection generator 4 is amplified and limited in the amplifier-limiter 5 and fed to the input of the frequency detector 6, from which the sign-polar signal is fed to the operating signal. amplifier 7 is converted to a voltage proportional to the speed deviation from the average value. The deviation passed through the filter 8, tuned to the resonant frequency of the speed sensor 3, changes the rotational speed of the receiving node 1.

To maintain the magnitude of the tension force at a certain level, the analog control signal of the input unit 2 is generated at the output of the multiplying digital-analog converter in the form of Uynp-, where V is the current value of the speed of the magnetic tape;

W - the current value of the angular velocity of the feed node.

Forming Uynp. occurs as follows. Pulses from the output of the angular velocity sensor 9, whose frequency is proportional to the angular velocity of rotation of the feeding unit 2, in the form of allowing the start of counting go to the counter 10, the second input of which constantly receives pulses from the output of the generator 11 standard pulses. The number of pulses that have time to arrive from the generator 11 for the period between two consecutive pulses of the sensor 9 of the angular velocity counter 10 translates into a binary code, which is stored in memory register 12 until the next pulse arrives. At its output, therefore, a signal is generated in binary

code, directly proportional to the period or inversely proportional to the angular velocity of rotation of the feeding unit 2. At the second input, the Current speed of the multiplying digital-to-analog converter is formed depending on the signal from the deviation of the current speed of the magnetic tape. The analog signal from the output of the multiplying digital-to-analog converter 13 controls the moment of the feeding unit 2, which leads to the determination of the required value of the magnitude of the magnetic tension j eHTbi.

Claims (1)

Invention Formula A device for controlling the speed of movement of a magnetic tape, comprising 5 receiving and feeding nodes with control inputs, a linear speed frequency sensor connected via a deflection generator with an analog converter containing series-connected limiting amplifier, a frequency detector, 0 an amplifier and a filter, as well as a multiplying unit associated with the control input of the feed node, characterized in that, in order to reduce control error, a frequency sensor of the angular velocity of rotation of the feed node, the output of which is connected to, is entered into it the counter and the input "reset the entered memory register, a generator of standard pulses connected through a counter to the memory register, and the multiplying block is designed as a multiplying digital analogue converter, the first input of which is one with a yield of the memory register and the second input of the "current speed - a filter output analog converter and a control input of the receiving node.