SU930376A1 - Device for demagnetization of magnetic tape web - Google Patents

Description

one

The invention relates to instrument making, in particular to devices for demagnetizing a magnetic tape.

A device for demagnetization of a magnetic tape roll is known, in which demagnetization occurs when it is moved between two cylindrical electromagnets tl.

However, such a device is inconvenient for use, since a special mechanism is required to move the magnetic tape.

It is also known a device for demagnetizing a magnetic tape containing two mutually perpendicularly located one inside another electromagnet, a high-voltage capacitor and a power source. .

A coil with a roll of magnetic tape for demagnetization is installed in the space inside the electromagnets.

The known device does not allow the dc5 to demagnetize a roll of magnetic tape effectively enough, since demagnetization of the transverse component of the magnetic field does not occur.

The purpose of the invention is to increase the efficiency of magnetising a roll of magnetic tape.

This goal is achieved in that the device for demagnetizing a roll of magnetic tape, containing two mutually opposite one inside another electromagnet, high-voltage capacitor and power source, introduced an additional two electromagnets in the form of two spirals, one above the other at a distance equal to the height of the roll with magnetic tape, inside mutually perpendicular electromagnets, and an electronic switchboard, with the beginning of the windings of mutually perpendicular and spiral electrons - filaments, rows from the middle part of the spiral windings of the electromagnets, one terminal of the capacitor and an output connected to the power source switch, and the ends of syncope electromagnets vtorry capacitor, the second output power source and a common switch contact connected to the common bus.

Figure 1 shows the proposed device; figure 2 - section aa in figure 1; Fig. 3 is an electrical circuit of the device.

The device contains two straight angular mutually perpendicular windings 1 and 2 in the plane, two flat spiral windings 3, divided into two halves 4 and 5, an electronic switch 6, a storage discharge capacitor 7, a power source 3 and a common bus 9. Moreover, the electronic switch has a common contact 10. The spiral winding is a single, round, flat (atushku, in which each subsequent coil has an increment of the radius by the size of the drive diameter. One end of the windings 1,2 and 3 is one of the conclusions of the cumulative discharge cond nsatora 7 and one of the terminals of the power supply 8 are connected to a common bus (Figure 2). All of the other terminals of the windings 1,2 and 3 are connected to the electronic switch sootg sponding contacts 6.

The device works as follows.

A roll of magnetic carrier is placed between two spiral partitioned windings 3; Next, the spiral windings 3 with a roll of magnetic carrier are placed in the rectangular wrap 2. Next, the roll of magnetic carrier with two partitioned windings 3 and with the rectangular winding 2 is placed in the rectangular winding 1, mutually perpendicular to the winding 2. The entire assembly is connected to the electronic switch 6, after which the device is ready for operation. When the device is turned on, the capacitor 7 is connected via a switch 6 to the power supply and is charged to a certain voltage. When the voltage reaches the set value, the electronic switch 6 disconnects the capacitor 7 tons of the power source and connects it to the output winding 1I carried out its oscillating discharge. The discharged capacitor is connected to the power source 8 again and after charging to a certain voltage the electronic switch connects it to

the conclusion of the next winding. Thus, t using the electronic switch 6, the storage capacitor 7 is charged and sequentially discharged to the windings 1,

2 and 3, as well as on sections 4 and 5 of the windings 3.

At each discharge cycle in the winding {or a section of the winding, an alternating, slowly decreasing magnetic field is formed, which affects the magnetic carrier accordingly. Thus, the demagnetization of the longitudinal and perpendicular components of the magnetization of the magnetic

the carrier is produced by the magnetic field of the mutually perpendicular windings 1 and 2, and by the transverse component of the magnetic field of the spiral windings 3. As the current passes through the entire spiral winding in the center of its equivalent cross section (AJ magnetic field is absent due to the change in direction of the closed magnetic field the floor around the coils winding, then.

In the leveling of the demagnetization level of the transverse component, the spiral winding in the device is divided into two halves. Connecting the discharge storage capacitor, first to the entire winding and then to individual half of the winding, allows the magnetic field of zero intensity to be moved along the spiral winding.

Thus, the demagnetization efficiency in the proposed device is achieved by increasing the magnetic field strength in the transverse direction of the magnetic carrier by a factor of 2-3 compared with the known one.

Claims (1)

Invention Formula A device for demagnetizing a roll of magnetic tape containing two mutually perpendicularly located one inside the other electromagnet, a high-voltage capacitor and a power source, characterized in that, in order to increase the efficiency of degaussing a roll of magnetic tape,