SU1065876A1 - Process for magnetic recording and reproducing with non-mechanical scanning of medium and universal scanning magnetic head - Google Patents

Abstract

1. The method of magnetic recording and BOQ-. products with non-mechanical scanning of the carrier, consisting in scanning the recording areas along the working gap. universal magnetic head by moving the magnetic field saturation areas by applying variable control magnetic fields, characterized in that, in order to improve the recording and reproduction quality of the universal magnetic head, saturated areas are created in the first half of the magnetic circuit from one side and in the second half from the side the other end of the working gap with the formation of a single boundary plane. (L / 9 1 O5 ate 00 a / 5

Description

2. Scanning universal magnetic head containing a magnetic core with two side branches, between which there is a working gap, a recording and playback winding and two control windings in the windows of the side branches of the magnetic core, characterized in that, in order to simplify the design, the side branches of the magnet

The toproid is made narrower in height of the working gap of the magnetic head and with the opposite direction of the constrictions, and the control windings are made in two sections and are included, both sections of each winding are located on different sides relative to the corresponding window.

one

The invention relates to instrumentation, in particular, to a technique of magnetic video recording, and can be used in television, computer technology, as well as for recording fast processes.

The known method of magnetic video recording and the universal head, according to which non-mechanical scanning of the tape at an angle is carried out due to the influence of alternating magnetic fields not on the magnetic circuit of the head, but on the closing field of the head, an auxiliary magnetic circuit, i.e. there are two magnetically conductive assemblies; in the first, a magnetic field is generated modulated by the recorded signal, and in the second, a scanning magnetic field {.

The magnetic field of the signal closes through a relatively large gap, which is the basis of the magnetic tape, which increases the area of magnetization. The area of magnetization along the direction of movement of the tape is even larger, it increases, because, in addition to the gap, it is determined by the width of the closing surfaces of the recording and scanning magnetic circuits. All this greatly reduces the quality of the recording.

The closest in technical essence and the achieved result is a method of magnetic recording and reproduction with non-mechanical scanning of the carrier, in which recording and reproduction is carried out by a single effective slit moving across the carrier from one edge of the head to another using a magnetic sweep, while recording magnetic the flux moving with the effective slot. varies depending on the magnitude of the desired signal.

A magnetic head is also known, which allows the creation of two magnetic circuits with oppositely directed skies, or negative fields that disappear inside the area in which the signal magnetic field is recorded on magnetic tape 2.

The disadvantages of the known head are the low quality of recording and reproducing and the complexity of its design.

The purpose of the invention is to improve the recording and reproduction quality of the universal magnetic head and simplify the design of the scanning head.

The goal is achieved in that according to the method of magnetic recording and playback; 0 works with non-mechanical scanning of the carrier, involving scanning the recording area along the working gap of the universal magnetic head by moving the saturation regions of the magnetic conduit by imposing variable control magnetic fields, saturated areas are created in the first half of the magnetic circuit from one side and the second half from the other the end of the working gap with the formation of a single boundary plane.

In addition, in the scanning universal magnetic / tin containing a magnetic core with two side branches, between the bores there is a working gap, a recording and playback winding and two cranking windings in the windows of the side branches of the magnetic circuit, the side branches of the magnetic circuit are made narrower in height of the working gap of the magnetic head and with the opposite direction of the constrictions, and the control windings are made in two sections and according to the included ones, with both sections of each winding being located on opposite sides with respect to corresponding window.

FIG. I shows a universal scanning magnetic head, general view; in fig. 2 - head magnetic core; FIG. 3 shows a record and play winding; in fig. 4 — first and second control windings; in fig. 5 - timing diagrams that show how the head works.

The scanning universal magnetic head contains a magnetowire 1 with the first 2 and second 3 side branches, between which there is a working gap 4,

the recording and replaying winding 5, the first 6 and second 7 control windings in the derv 8 and second 9 windows of the side branches of the magnetic conductor, the first control winding 6 made of the first 10 and second 11 sections, and the second control winding 7 from the first 12 and the second 13 sections included under. Scanning of the carrier 14 is carried out by skakHj pOBaHHH recording zones 15 along the working gap 4 when creating the first 16 and second 17 saturated regions in the first 18 and second 19 halves of the magnetic circuit I with the formation of a single boundary plane 20.

Scanning magnetic head works as follows.

The control windings 6 and 7 supply current pulses with a signal sweep frequency. In this case, in the winding 7, the current during each cycle increases its value, and at the end of the cycle it abruptly decreases to its initial value, and in the winding 6, the current value during each cycle varies from a certain value to zero or decreases to the first value, and at the end of the cycle, it jumps to its original value. In the narrower part of the magnetic circuit, saturation occurs at lower values of current than in more than 1 of the upper part; therefore, F the beginning of each cycle in the region of winding 6 is all unsaturated, and in the region of winding 7 we have 1 | schons. As the current in the winding 6 increases, the saturation region moves from bottom to top and the saturation region increases, and in windings 7 to decrease the current, the saturation region decreases and the boundary of this region moves upwards.

The method of magnetic recording and reproduction with non-mechanical. Media scanning is carried out as follows.

The method of magnetic recording and reproduction with non-mechanical scanning of the carrier is carried out as follows.

From the diagram (Fig. 5a, b) it can be seen that the currents .i in the control windings 6 and 7 (Fig. 1) change in antiphase. Thus, with an increase in current i%, in the control winding 6, a portion of the magnetic core (Fig. 1) is saturated from the bottom of the gate, while the current V1 in the control winding 7 decreases and the saturation region also decreases, shifting from bottom to top. The magnitude of the currents and iy depends on the material of the magnetic circuit and is chosen so that at the maximum current iy, p of the winding region 6, the magnetic conductor is completely saturated, at this time the current strength iy is such that in the winding region 7 the magnetic conductor is unsaturated, and vice versa for the minimum y, and the maximal i of the current. The frequency of change of these currents depends on the specific conditions. For example, when recording a single line of television signal on a single track, the rise time of the current iy and the decrease time of the current iyi are equal to the transit time P of the electron beam along this row. The return time of these currents to the initial state is equal to the time of the return path of the beam in the thermovision tube. FIG. 5 g shows the position of the active site in time. The value of xsh must be less than or equal to the length of the working gap of the magnetic head. The movement of the active area along the length of the working gap occurs with the same frequency with which the control currents iv, and h ,, change. The magnitude of the current i (Fig. 5d) depends on the material of the magnetic circuit, the size of the working gap of the magnetic head, such as a magnetic tape, as well as the parameters of the electrical part of the recording and playback equipment. FIG. 5e shows the location of the working gap from. relative to the magnetic tape, as well as magnetic field lines FS, which are created by the current of the useful signal i in the winding 5. The magnetic tape touches the head only in the area of the working gap in which the recording section moves, therefore the magnetic tape is affected only by the current FS of the useful signal and is not affected magnetic flux generated by control windings, laziness.

M 1 tape only touches the head in the area of the working gap in which the recording section moves, therefore only the flow F of the useful signal affects the magnetic tape and is not affected by the magnetic flux created by the control windings.

If current winding pulses iy and iy, of a certain form and with a frequency of sweep, are applied to the windings. 7 and 7 controls, then the gentle power lines from the magnetic field of the winding 5 generated by the current i will converge on the active head section at one point which moves across the active section with the frequency of the control currents iy and iy. The alternating magnetic field created by the current i, in the winding 5, affects the magnetic tape 14 at only one point of the core IS. Moving, this point records the signal on the magnetic tape 14 as a magnetic track. At the moment when the next track starts recording, the magnetic tape 14 is moved to the required distance relative to zone 1e1.

Thus, it is possible to move the recording point with a fixed magnetic head relative to the tape at a high speed, which is determined by the frequency of the control currents and the saturation rate of the plates. When playing the magnetic field of the tape 14 affects only the working point of the active zone 15 and excites the EMF

in the winding 5. The rest of the work of the head is similar to the work when recording information. In the proposed magnetic head, both the shape of the magnetic circuit (the details of a complex configuration are missing) and the shape of the magnetic fields, which is close to the circumference for control fields, are degraded. Therefore, the control magnetic fields in the head have less power and, due to their distance from the magnetic tape, eliminate recording noise, while in the well-known head, the gaps of the magnetic cores through which the scanning fields pass are in close proximity to the magnetic tape and some of their surfaces. even touching the tape. As a result, the proposed head provides a higher recording quality than is known. In addition, if in a known head both

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the floor scanners are visited, the unsaturated region disappears and the recording stops. In the proposed magnetic go.povka this leads only to a small increase in the size of the core during recording, which indicates a higher reliability of the device.

In the well-known head there are numerous joints and gaps, especially in symmetric magnetic cores, even a slight skew or excessive gap breaks the symmetry, which is a factor of interference and refusals. In the proposed head such gaps are absent and can not cause interference.

Thus, the invention provides better recording quality, improves reliability, is simpler in design to more technological.

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Claims (2)

1. The method of magnetic recording and production with non-mechanical scanning of the medium, which consists in scanning the recording zones along the working gap, the universal magnetic head by moving the saturation areas of the magnetic circuit by applying alternating control magnetic fields, characterized in that, in order to improve recording quality and reproduction by a universal magnetic head, saturated regions are created in the first half of the magnetic circuit from one side, and in the second half from the other end of the working about the gap with the formation of a single boundary plane. fig1 2. Scanning universal magnetic head containing a magnetic circuit with two lateral branches, between which there is a working gap, a recording and playback winding and two control windings in the windows of the lateral branches of the magnetic circuit, characterized in that, to simplify the design, the lateral branches of the magnesium of the axle are made narrowing along the height of the working gap of the magnetic head and with the opposite direction of the constrictions, and the control windings are made two-sectional and included, both sections of each winding olozheny on opposite sides of the corresponding window.