CN112837705A - Demagnetizing method with magnetic field capable of being inverted - Google Patents
Demagnetizing method with magnetic field capable of being inverted Download PDFInfo
- Publication number
- CN112837705A CN112837705A CN202110214676.0A CN202110214676A CN112837705A CN 112837705 A CN112837705 A CN 112837705A CN 202110214676 A CN202110214676 A CN 202110214676A CN 112837705 A CN112837705 A CN 112837705A
- Authority
- CN
- China
- Prior art keywords
- field intensity
- degaussing
- signal
- coil
- magnetic medium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/465—Arrangements for demagnetisation of heads
Landscapes
- Video Image Reproduction Devices For Color Tv Systems (AREA)
Abstract
The invention provides a demagnetizing method with an invertible magnetic field. Step 1: a field intensity conversion control unit is arranged between the demagnetizing coil and the energy storage equipment in advance, and the demagnetizing coil is connected with a field intensity induction sensor and an information detection sensor; step 2: a degaussing signal is sent to the magnetic medium through the degaussing coil to carry out first degaussing, and a field intensity induction signal is generated in the field intensity induction sensor; and step 3: according to the field intensity induction signal, field intensity conversion is carried out through the field intensity conversion control unit, and after the field intensity conversion, a demagnetizing signal is sent to the magnetic medium again through the demagnetizing coil to be demagnetized again: and 4, step 4: and repeating the step 3, judging whether information exists in the magnetic medium through the information detection sensor, and controlling the degaussing coil to stop sending the degaussing signal when the information does not exist in the magnetic medium.
Description
Technical Field
The invention relates to the technical field of information security and demagnetization processing, in particular to a demagnetization method with an invertible magnetic field.
Background
At present, the existing demagnetization method destroys a magnetic medium by adopting a mode of once discharging and fixing the field intensity direction, but with the improvement of the manufacturing process of the magnetic medium and the uncertainty of the using environment, the phenomenon that the generated field intensity cannot overcome the coercive force of the magnetic medium and the demagnetization is not complete can occur, so that the information leakage is easily caused, and therefore, how to use the demagnetization method with the adjustable demagnetization times through the inversion of the field intensity direction is the research direction of the invention.
Disclosure of Invention
The invention provides a demagnetizing method with an invertible magnetic field, which is used for solving the problems that the field intensity generated by the uncertain demagnetizing method cannot overcome the coercive force of a magnetic medium and the demagnetization is not complete due to the improvement of the manufacturing process of the magnetic medium and the uncertainty of the using environment, and the information leakage is easily caused.
A method of field reversible degaussing comprising:
step 1: a field intensity conversion control unit is arranged between the demagnetizing coil and the energy storage equipment in advance, and the demagnetizing coil is connected with a field intensity induction sensor and an information detection sensor;
step 2: a degaussing signal is sent to the magnetic medium through the degaussing coil to carry out first degaussing, and a field intensity induction signal is generated in the field intensity induction sensor;
and step 3: according to the field intensity induction signal, field intensity conversion is carried out through the field intensity conversion control unit, and after the field intensity conversion, a demagnetizing signal is sent to the magnetic medium again through the demagnetizing coil to be demagnetized again:
and 4, step 4: and repeating the step 3, judging whether information exists in the magnetic medium through the information detection sensor, and controlling the degaussing coil to stop sending the degaussing signal when the information does not exist in the magnetic medium.
As an embodiment of the present invention: the setting up field intensity conversion control unit between degaussing coil and energy storage equipment in advance includes:
acquiring a connecting circuit of the demagnetizing coil, and setting a switching program for controlling field intensity conversion of the demagnetizing coil through a preset program;
determining a control signal for field intensity conversion according to the switching program;
and controlling the field intensity conversion of the degaussing coil according to the control signal, and taking the switch program as a field intensity conversion control unit.
As an embodiment of the present invention: the field intensity induction sensor is used for acquiring the current direction of the degaussing coil when the degaussing coil sends a degaussing signal, and determining the real-time field intensity and the real-time field intensity direction of the degaussing signal.
As an embodiment of the present invention: the information detection sensor is used for detecting whether the magnetic medium contains an information track or not and generating a degaussing success signal when the information track does not exist in the magnetic medium.
As an embodiment of the present invention: the energy storage device comprises a first energy storage device and a second energy storage device, wherein the polarity of the first energy storage device is opposite to that of the second energy storage device, and the first energy storage device and the second energy storage device are connected with the degaussing coil.
As an embodiment of the present invention: the information detection sensor detects whether the magnetic medium contains an information track or not, and comprises the following steps:
step A1, transmitting direct current pulses to the magnetic medium through the information detection sensor, and determining pulse signal feedback parameters:
wherein, wiRepresenting the content characteristics of the ith feedback signal of the magnetic medium in a degaussing period; x is the number ofiRepresenting the signal length of the ith feedback signal of the magnetic medium in a degaussing period; y isiRepresenting the signal duration of the ith feedback signal of the magnetic medium in a degaussing period; 1, 2, 3, … … n; n represents the total number of magnetic media feedback signals;
step A2: according to the feedback parameters, comparing by the following formula to determine a comparison value:
wherein j represents a contrast signal of the information track; d represents a contrast parameter of the frequency of occurrence of the information track; when J is more than or equal to 1, the information-containing track is shown; when J < 1, no information track is contained.
As an embodiment of the present invention: the step 2 comprises the following steps:
according to the field intensity induction sensor, when the degaussing coil is determined to be started, calculating the real-time field intensity of the magnetic medium, and determining field intensity information; wherein the content of the first and second substances,
the field intensity information comprises field intensity and field intensity direction;
determining the transmitting power of the degaussing coil according to the field intensity;
determining the working power of the degaussing coil according to the transmitting power;
adjusting the current and voltage for driving the degaussing coil according to the working power;
and generating a field strength induction signal according to the current and the voltage.
As an embodiment of the present invention: the step 2 further comprises:
step S1, acquiring the trial charge amount and the degaussing distance of the degaussing coil when field intensity induction is carried out according to the field intensity induction sensor, and determining the active power when the degaussing coil is started:
wherein K represents a constant; q represents the charge amount of the detection charge emitted by the field strength induction sensor; d represents the distance between the two ends of the degaussing coil; sPRepresenting the actual power of the degaussing coil; i isbRepresenting the actual current of the degaussing coil; rzRepresents the resistance value of the degaussing coil; rfRepresents a parasitic capacitance; pERepresents the rated power of the degaussing coil; pXRepresents the active power at the start of the degaussing coil:
step S2, acquiring a real-time detection signal of the degaussing coil, and determining the active power of the degaussing coil after starting:
wherein E represents the field strength voltage; sPRepresenting the actual power; i ishRepresenting the constant current after the field intensity direction; pqPqRepresenting the active power of the demagnetizing coil after starting;
step S3, determining the signal parameters of the field strength induction sensor according to the active power consumption when the degaussing coil is started and the active power after the degaussing coil is started:
and when the delta C is less than 0, the information of the field intensity induction signal is the direction of converting the field intensity.
As an embodiment of the present invention: the step 3 comprises the following steps:
acquiring the field intensity induction signal and determining a real-time degaussing signal;
transmitting the real-time degaussing signal to the field intensity conversion control unit, and triggering field intensity conversion control response in the field intensity conversion control unit;
generating a field intensity conversion signal according to the field intensity conversion control response;
sending the field intensity conversion signal to a degaussing coil and energy storage equipment, and converting the current direction of the degaussing coil and the polarity direction of the energy storage equipment;
after the current direction of the demagnetizing coil and the polarity direction of the energy storage device are changed, determining the field intensity direction after the change;
and according to the converted field intensity direction, sending a degaussing signal to the magnetic medium through the degaussing coil to degausse the magnetic medium.
The invention has the beneficial effects that: the invention relates to a processing method for destroying information of a magnetic medium, which aims to protect the information security and enhance the reliability of destroying confidential information. The energy storage device of the invention can adapt to repeated change of the magnetic field (namely polarity inversion) and can store and release energy efficiently. The strong conversion control unit controls a part of the degaussing unit (degaussing coil) to realize automatic inversion of the field intensity direction, and then the field intensity direction can be judged by the field intensity induction sensor every time through automatic inversion of the field intensity direction for many times, and the current direction is changed through a program switch generated by control software. The invention achieves the effect that the field intensity direction of the degaussing unit can be inverted, and meanwhile, the same medium to be destroyed can be destroyed for many times in a short time, thereby achieving higher confidentiality level.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is a flow chart of a method for demagnetizing a magnetic field with an reversible change in magnetic field according to an embodiment of the present invention;
fig. 2 is a circuit diagram of an embodiment of real-time degaussing according to the present invention.
Detailed Description
The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.
As shown in fig. 1, the present invention is a demagnetizing method with reversible magnetic field, comprising:
step 1: a field intensity conversion control unit is arranged between the demagnetizing coil and the energy storage equipment in advance, and the demagnetizing coil is connected with a field intensity induction sensor and an information detection sensor;
step 2: a degaussing signal is sent to the magnetic medium through the degaussing coil to carry out first degaussing, and a field intensity induction signal is generated in the field intensity induction sensor;
and step 3: according to the field intensity induction signal, field intensity conversion is carried out through the field intensity conversion control unit, and after the field intensity conversion, a demagnetizing signal is sent to the magnetic medium again through the demagnetizing coil to be demagnetized again:
and 4, step 4: and repeating the step 3, judging whether information exists in the magnetic medium through the information detection sensor, and controlling the degaussing coil to stop sending the degaussing signal when the information does not exist in the magnetic medium.
The principle and the beneficial effects of the technical scheme are as follows: the invention relates to a processing method for destroying information of a magnetic medium, which aims to protect the information security and enhance the reliability of destroying confidential information, and the invention carries out control change according to the defects that the field intensity of the original demagnetizer is irreversible, a magnetic field can be generated only along one direction, and the demagnetization times must be carried out manually. The energy storage device of the present invention can adapt to repeated changes in magnetic field (i.e., polarity switching, based on polar capacitance or other polar materials), and can efficiently store and release energy. The strong conversion control unit controls a part of the degaussing unit (degaussing coil) to realize automatic inversion of the field intensity direction, and then the field intensity direction can be judged by the field intensity induction sensor every time through automatic inversion of the field intensity direction for many times, and the current direction is changed through a program switch generated by control software. The invention achieves the effect that the field intensity direction of the degaussing unit can be inverted, and meanwhile, the same medium to be destroyed can be destroyed for many times in a short time, thereby achieving higher confidentiality level.
In a practical embodiment, as shown in FIG. 2: in the circuit diagram of fig. 2, 6 switching devices K1-K6 (which may be relays, thyristors or field effect transistors) are controlled to realize inversion of the direction of the demagnetizing field, and the switching devices are controlled to be switched on and off by a field intensity switching control unit. And the degaussing coil is connected with the field intensity induction sensor to determine the field intensity direction.
In the specific working process, at the beginning, K1-K4 is switched off, K5 and K6 are switched on, and the equipment charges the degaussing power supply 1 and the degaussing power supply 2. When the capacitor is fully charged, firstly K6 is switched off, K1 and K4 are switched on, and K2 and K3 are switched off, so that current passes through the degaussing unit from A to B; after the demagnetization is finished, K5, K1 and K4 are switched off, K6, K2 and K3 are switched on, at the moment, the current passes through the demagnetization unit from B to A, the second demagnetization is finished, the change of the circuit is only illustrated in the attached figure 2, the demagnetization control circuit further comprises a program for controlling field intensity transformation, the program is implanted into a control board for controlling the demagnetization machine to realize the demagnetization twice or more, and the direction of the demagnetized magnetic field is continuously reversed.
As an embodiment of the present invention: the setting up field intensity conversion control unit between degaussing coil and energy storage equipment in advance includes:
acquiring a connecting circuit of the demagnetizing coil, and setting a switching program for controlling field intensity conversion of the demagnetizing coil through a preset program; the program switch is arranged on the connecting circuit and is controlled by programming according to the control device on the connecting circuit
Determining a control signal for field intensity conversion according to the switching program;
and controlling the field intensity conversion of the degaussing coil according to the control signal, and taking the switch program as a field intensity conversion control unit.
The principle and the beneficial effects of the technical scheme are as follows: the invention realizes the field intensity conversion based on the strong conversion control unit, and the degaussing direction is changed after the field intensity conversion, and the degaussing is realized for many times by continuously changing.
As an embodiment of the present invention: the field intensity induction sensor is used for acquiring the current direction of the demagnetizing coil when the demagnetizing coil sends a demagnetizing signal, and determining the real-time field intensity and the real-time field intensity direction of the demagnetizing signal.
The principle and the beneficial effects of the technical scheme are as follows: the direction of the current and the magnitude of the current determine the magnitude of the degaussing capability, so the invention detects the magnitude and the direction of the field intensity, and then the magnitude and the direction of the field intensity are adjusted to realize the rotation of degaussing. The magnitude of the field intensity is determined by the quantity of the detection charges emitted by the field intensity induction sensor, and the direction of the field intensity is reflected in the current direction of the degaussing coil.
As an embodiment of the present invention: the information detection sensor is used for detecting whether the magnetic medium contains an information track or not and generating a degaussing success signal when the information track does not exist in the magnetic medium.
The principle and the beneficial effects of the technical scheme are as follows: the information detection sensor is a programmed sensor, belongs to an information detection program and has the following principle: if the floating grid is electrified, the existence of the information track is indicated. Therefore, the invention judges whether the information track exists by detecting whether the information track exists in the magnetic medium, and further judges whether the demagnetization succeeds.
As an embodiment of the present invention: the energy storage device comprises a first energy storage device and a second energy storage device, wherein the polarity of the first energy storage device is opposite to that of the second energy storage device, and the first energy storage device and the second energy storage device are connected with the degaussing coil.
The principle and the beneficial effects of the technical scheme are as follows: the energy storage unit generates opposite currents and currents in two directions through the conversion control unit, and therefore erasing in two directions is achieved. Because the current direction of the demagnetization unit is changed, an alternating magnetic field is generated in the demagnetization unit, one energy storage component discharges to the coil, the two energy storage components are connected to the coil at the same time, but the polarities of the two energy storage components are opposite, so that the two energy storage components are controlled to discharge respectively, currents in different directions can be generated in the coil, and magnetic fields in different directions can be generated at the same time. The energy storage component is a capacitor bank, and a plurality of capacitors are connected in series and in parallel inside the energy storage component. The power supply charges it, and after a certain voltage, the thyristor controls it to discharge to the coil.
As an embodiment of the present invention: the information detection sensor detects whether the magnetic medium contains an information track or not, and comprises the following steps:
step A1, transmitting direct current pulses to the magnetic medium through the information detection sensor, and determining pulse signal feedback parameters:
wherein, wiRepresenting the content characteristics of the ith feedback signal of the magnetic medium in a degaussing period; x is the number ofiRepresenting the signal length of the ith feedback signal of the magnetic medium in a degaussing period; y isiRepresenting the signal duration of the ith feedback signal of the magnetic medium in a degaussing period; 1, 2, 3, … … n; n represents the total number of magnetic media feedback signals;
when the feedback parameter of the pulse signal is determined, the invention defines a period, because within the period, the hard disk can be demagnetized once, and the content characteristic of the feedback signal is whether the floating gate of the memory device which is fed back contains current or not; the length of the feedback signal represents the continuous state or the discontinuous state of the feedback signal and also represents the length of the information track, and the duration of the feedback signal is the time of the stage of starting to have the feedback signal and the final feedback signal and is used for determining the whole area needing to be demagnetized again. By combining the content of the feedback signal with an exponential function, the pulse signal feedback parameter can be embodied in the form of a graph.
Step A2: according to the feedback parameters, comparing by the following formula to determine a comparison value:
wherein j represents a contrast signal of the information track; d represents a contrast parameter of the frequency of occurrence of the information track; when J is more than or equal to 1, the information-containing track is shown; when J < 1, no information track is contained.
The comparison signal of the information track and the comparison parameter of the occurrence frequency of the information track are preset by a user, and the feedback signal is embodied in a chart form, so that the comparison with the parameter set by the user is facilitated, whether the information track exists or not is judged, and when the information track is embodied in the chart form in a computer, the information track and the area of the information track can also be judged.
The principle and the beneficial effects of the technical scheme are as follows:
the invention transmits direct current pulse to the magnetic medium through the information detection sensor, constructs a pulse signal feedback model, the feedback model is used for judging whether an information track exists in the magnetic medium, the detection model is used for detecting the feedback condition, if the feedback exists, the information track also exists, and finally, whether demagnetization succeeds or not is determined based on real-time judgment.
As an embodiment of the present invention: the step 2 comprises the following steps:
according to the field intensity induction sensor, when the degaussing coil is determined to be started, calculating the real-time field intensity of the magnetic medium, and determining field intensity information; wherein the content of the first and second substances,
the field intensity information comprises field intensity and field intensity direction;
determining the transmitting power of the degaussing coil according to the field intensity;
determining the working power of the degaussing coil according to the transmitting power;
adjusting the current and voltage for driving the degaussing coil according to the working power;
and generating a field strength induction signal according to the current and the voltage.
The principle and the beneficial effects of the technical scheme are as follows: after the field intensity and the field intensity direction are clarified, the strong induction sensor still needs to control the demagnetizing coil in the form of current and voltage, so the invention calculates the real-time field intensity of the magnetic medium to further control the demagnetizing coil to generate the same demagnetizing signal, but the directions are opposite, thereby realizing repeated demagnetization. The transmitting power can be directly determined through the strength of the field intensity, then the working power is determined according to the auxiliary circuit and the control circuit of the degaussing coil, the working power is larger than the transmitting power, and finally the current and the voltage are determined, wherein the finally determined current and voltage are the current and the voltage which are controlled by the control device and sent from the power supply output end, so that the comprehensive regulation of the whole circuit is realized.
As an embodiment of the present invention: the step 2 further comprises:
step S1, acquiring the trial charge amount and the degaussing distance of the degaussing coil when field intensity induction is carried out according to the field intensity induction sensor, and determining the active power when the degaussing coil is started:
wherein K represents a constant; q represents the charge amount of the detection charge emitted by the field strength induction sensor; d represents the distance between the two ends of the degaussing coil; sPRepresenting the actual power of the degaussing coil; i isbRepresenting the actual current of the degaussing coil; rzRepresents the resistance value of the degaussing coil; rfRepresents a parasitic capacitance; pERepresents the rated power of the degaussing coil; pXRepresents the active power at the start of the degaussing coil:
in this step: the invention
ε represents a dielectric constant. In this process, power is suppliedThe product of voltage and current, but the invention calculates the active power according to the charge quantity in the field strength detection, the length of the degaussing end of the degaussing coil and the actual current more according to the accuracy of the active power because of the field strength.
Which represents the overall voltage during degaussing, the field strength inductive sensor determines the field strength formed by the degaussing coil by detecting charges (point charges), during which the field strength induced by the field strength inductive sensor simulates that the field strength formed by the degaussing coil is the same electric field internally. So that the voltage for doing work in the degaussing process can be deduced as
The actual current, +/-I, is obtained by calculation of the formulabThe expression ± represents the direction of current, and the current for performing work in the present invention is divided current including actually detectable current and devices such as resistance, and divided current by parasitic capacitance (mutual capacitance in wiring) in the circuit.
Step S2, acquiring real-time detection signals of the degaussing coil, and determining the active power of the degaussing coil after the field intensity direction is converted:
wherein E represents the field strength voltage; sPRepresenting the actual power; i ishRepresenting the constant current after the field intensity direction; pqRepresenting the active power of the demagnetizing coil after starting;
the active power of the demagnetizing coil after the field intensity direction is converted is the work done by the demagnetizing coil, and through the field intensity electricity (the actual working voltage of the demagnetizing coil is determined by the field intensity and is called field intensity voltage), the field in one period is the field in one period because of the uniform current circuit of the inventionThe strength is constant.
The calculated result is the resistance in the degaussing circuit, and then the power of the degaussing coil is obtained by comparing the square of the voltage of the field strength with the resistance value.
Step S3, determining the signal parameters of the field strength induction sensor according to the active power consumption of the degaussing coil when the degaussing coil is started and the active power of the degaussing coil after the degaussing coil is started:
and when the delta C is less than 0, the information of the field intensity induction signal is the direction of converting the field intensity.
In the last calculation step, the invention achieves repeated elimination by magnetic field inversion back and forth, so that PX+PqIf 0 or less, it means that the field strength direction has changed, whereas if PX+PqIf greater than 0, this indicates that the field strength direction has not changed. And: (P)X+Pq)-(±Ib)2(Rz+Rf) And the method is used for judging whether the sum of the two active powers exceeds the constant power, wherein the sum of the two active powers indicates that a period is completed when the constant power is exceeded, and indicates that the operation can be continued in the period when the constant power is not exceeded.
The beneficial effects of the above technical scheme are that: in the calculation process of the field strength induction signal, the active power consumption of the voltage of the demagnetizing coil is determined, the active power consumption of the induction is determined, and then the adjustment parameters of the field strength induction signal are judged by comparing the actual active power consumption of the demagnetizing coil with the constant power, so that the stable control of the field strength is realized.
As an embodiment of the present invention: the step 3 comprises the following steps:
acquiring the field intensity induction signal and determining a real-time degaussing signal;
transmitting the real-time degaussing signal to the field intensity conversion control unit, and triggering field intensity conversion control response in the field intensity conversion control unit;
generating a field intensity conversion signal according to the field intensity conversion control response;
sending the field intensity conversion signal to a degaussing coil and energy storage equipment, and converting the current direction of the degaussing coil and the polarity direction of the energy storage equipment;
after the current direction of the demagnetizing coil and the polarity direction of the energy storage device are changed, determining the field intensity direction after the change;
and according to the converted field intensity direction, sending a degaussing signal to the magnetic medium through the degaussing coil to degausse the magnetic medium.
The principle and the beneficial effects of the technical scheme are as follows: the invention relates to a processing method for destroying information of a magnetic medium, which aims to protect the information security and enhance the reliability of destroying confidential information. The energy storage device of the invention can adapt to repeated change of the magnetic field (namely polarity inversion) and can store and release energy efficiently. The strong conversion control unit controls a part of the degaussing unit (degaussing coil) to realize automatic inversion of the field intensity direction, and then the field intensity direction can be judged by the field intensity induction sensor every time through automatic inversion of the field intensity direction for many times, and the current direction is changed through a program switch generated by control software. The invention achieves the effect that the field intensity direction of the degaussing unit can be inverted, and meanwhile, the same medium to be destroyed can be destroyed for many times in a short time, thereby achieving higher confidentiality level.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (9)
1. A method of field reversible degaussing comprising:
step 1: a field intensity conversion control unit is arranged between the demagnetizing coil and the energy storage equipment in advance, and the demagnetizing coil is connected with a field intensity induction sensor and an information detection sensor;
step 2: a degaussing signal is sent to the magnetic medium through the degaussing coil to carry out first degaussing, and a field intensity induction signal is generated in the field intensity induction sensor;
and step 3: according to the field intensity induction signal, field intensity conversion is carried out through the field intensity conversion control unit, and after the field intensity conversion, a demagnetizing signal is sent to the magnetic medium again through the demagnetizing coil to be demagnetized again:
and 4, step 4: and repeating the step 3, judging whether information exists in the magnetic medium through the information detection sensor, and controlling the degaussing coil to stop sending the degaussing signal when the information does not exist in the magnetic medium.
2. The method of claim 1, wherein the step of providing a field strength switching control unit between the degaussing coil and the energy storage device in advance comprises:
acquiring a connecting circuit of the demagnetizing coil, and setting a switching program for controlling field intensity conversion of the demagnetizing coil through a preset program;
determining a control signal for field intensity conversion according to the switching program;
and controlling the field intensity conversion of the degaussing coil according to the control signal, and taking the switch program as a field intensity conversion control unit.
3. The method of claim 1, wherein the field strength sensor is configured to obtain a current direction of the degaussing coil when the degaussing coil emits the degaussing signal, and determine a real-time field strength and a real-time field strength direction of the degaussing signal.
4. The method of claim 1, wherein the information detecting sensor is configured to detect whether the magnetic medium contains information tracks and generate a degaussing success signal when the information tracks are absent from the magnetic medium.
5. The method of claim 1, wherein the energy storage device comprises a first energy storage device and a second energy storage device, the first energy storage device and the second energy storage device having opposite polarities and being connected to the degaussing coil.
6. The method of claim 4, wherein the information detecting sensor detects whether the magnetic medium contains information tracks, comprising the steps of:
step A1, transmitting direct current pulses to the magnetic medium through the information detection sensor, and determining pulse signal feedback parameters:
wherein, wiRepresenting the content characteristics of the ith feedback signal of the magnetic medium in a degaussing period; x is the number ofiRepresenting the signal length of the ith feedback signal of the magnetic medium in a degaussing period; y isiRepresenting the signal duration of the ith feedback signal of the magnetic medium in a degaussing period; 1, 2, 3, … … n; n represents the total number of magnetic media feedback signals;
step A2: according to the feedback parameters, comparing by the following formula to determine a comparison value:
wherein j represents a contrast signal of the information track; d represents a contrast parameter of the frequency of occurrence of the information track; when J is more than or equal to 1, the information-containing track is shown; when J < 1, no information track is contained.
7. The method of claim 1, wherein the step 2 comprises:
according to the field intensity induction sensor, when the degaussing coil is determined to be started, calculating the real-time field intensity of the magnetic medium, and determining field intensity information; wherein the content of the first and second substances,
the field intensity information comprises field intensity and field intensity direction;
determining the transmitting power of the degaussing coil according to the field intensity;
determining the working power of the degaussing coil according to the transmitting power;
adjusting the current and voltage for driving the degaussing coil according to the working power;
and generating a field strength induction signal according to the current and the voltage.
8. The method of claim 1, wherein the step 2 further comprises:
step S1, acquiring the trial charge amount and the degaussing distance of the degaussing coil when field intensity induction is carried out according to the field intensity induction sensor, and determining the active power when the degaussing coil is started:
wherein K represents a constant; q represents the charge amount of the detection charge emitted by the field strength induction sensor; d represents the distance between the two ends of the degaussing coil; sPIndicating the actual work of the degaussing coilRate; i isbRepresenting the actual current of the degaussing coil; rzRepresents the resistance value of the degaussing coil; rfRepresents a parasitic capacitance; pERepresents the rated power of the degaussing coil; pXRepresents the active power at the start of the degaussing coil:
step S2, acquiring a real-time detection signal of the degaussing coil, and determining the active power of the degaussing coil after starting:
wherein E represents the field strength voltage; sPRepresenting the actual power; i ishRepresenting the constant current after the field intensity direction; pqRepresenting the active power of the degaussing coil after starting;
step S3, determining the signal parameters of the field strength induction sensor according to the active power consumption when the degaussing coil is started and the active power after the degaussing coil is started:
and when the delta C is less than 0, the information of the field intensity induction signal is the direction of converting the field intensity.
9. The method of claim 1, wherein step 3 comprises:
acquiring the field intensity induction signal and determining a real-time degaussing signal;
transmitting the real-time degaussing signal to the field intensity conversion control unit, and triggering field intensity conversion control response in the field intensity conversion control unit;
generating a field intensity conversion signal according to the field intensity conversion control response;
sending the field intensity conversion signal to a degaussing coil and energy storage equipment, and converting the current direction of the degaussing coil and the polarity direction of the energy storage equipment;
after the current direction of the demagnetizing coil and the polarity direction of the energy storage device are changed, determining the field intensity direction after the change;
and according to the converted field intensity direction, sending a degaussing signal to the magnetic medium through the degaussing coil to degausse the magnetic medium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110214676.0A CN112837705B (en) | 2021-02-25 | 2021-02-25 | Demagnetizing method with magnetic field capable of being inverted |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110214676.0A CN112837705B (en) | 2021-02-25 | 2021-02-25 | Demagnetizing method with magnetic field capable of being inverted |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112837705A true CN112837705A (en) | 2021-05-25 |
| CN112837705B CN112837705B (en) | 2022-05-17 |
Family
ID=75933528
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110214676.0A Active CN112837705B (en) | 2021-02-25 | 2021-02-25 | Demagnetizing method with magnetic field capable of being inverted |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112837705B (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4663676A (en) * | 1985-09-13 | 1987-05-05 | International Business Machines | Return to zero vertical magnetic recording system |
| CN1823370A (en) * | 2003-08-29 | 2006-08-23 | 东洋测器电脑株式会社 | Magnetic data erase device and magnetic data erase method |
| US20070047128A1 (en) * | 2005-08-31 | 2007-03-01 | Fujitsu Limited | Data erasing device using permanent magnet |
| JP2007213701A (en) * | 2006-02-09 | 2007-08-23 | Fujifilm Corp | Method of demagnetizing magnetic tape |
| CN101091210A (en) * | 2004-12-27 | 2007-12-19 | 东洋测器电脑株式会社 | Magnetic recording medium recorded data erasing device, magnetic recording medium recorded data erasing method, and program for controlling magnetic recording medium recorded data erasing device |
| CN102364577A (en) * | 2010-11-30 | 2012-02-29 | 中国电子科技集团公司第三十研究所 | Method for destroying data of magnetic medium and demagnetization magnetic field generation circuit |
| CN110797052A (en) * | 2019-10-21 | 2020-02-14 | 北京工业大学 | Rapid demagnetization method based on magnetic medium characteristics |
| CN110911231A (en) * | 2019-12-23 | 2020-03-24 | 贵州振华群英电器有限公司（国营第八九一厂） | Magnetizing and demagnetizing method and device for magnetic latching relay with built-in three-pole magnetic steel |
| CN111157924A (en) * | 2019-11-23 | 2020-05-15 | 重庆大学 | System and method for measuring and eliminating residual magnetic chain of three-phase transformer core |
| CN111816219A (en) * | 2020-07-09 | 2020-10-23 | 北京中超伟业信息安全技术股份有限公司 | Intelligent electromagnetic demagnetization system and method based on target identification |
| CN111816403A (en) * | 2020-07-09 | 2020-10-23 | 北京中超伟业信息安全技术股份有限公司 | Target position determining method and system for demagnetization |
| CN111816404A (en) * | 2020-07-15 | 2020-10-23 | 北京中超伟业信息安全技术股份有限公司 | Demagnetization method and system |
-
2021
- 2021-02-25 CN CN202110214676.0A patent/CN112837705B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4663676A (en) * | 1985-09-13 | 1987-05-05 | International Business Machines | Return to zero vertical magnetic recording system |
| CN1823370A (en) * | 2003-08-29 | 2006-08-23 | 东洋测器电脑株式会社 | Magnetic data erase device and magnetic data erase method |
| CN101091210A (en) * | 2004-12-27 | 2007-12-19 | 东洋测器电脑株式会社 | Magnetic recording medium recorded data erasing device, magnetic recording medium recorded data erasing method, and program for controlling magnetic recording medium recorded data erasing device |
| US20070047128A1 (en) * | 2005-08-31 | 2007-03-01 | Fujitsu Limited | Data erasing device using permanent magnet |
| JP2007213701A (en) * | 2006-02-09 | 2007-08-23 | Fujifilm Corp | Method of demagnetizing magnetic tape |
| CN102364577A (en) * | 2010-11-30 | 2012-02-29 | 中国电子科技集团公司第三十研究所 | Method for destroying data of magnetic medium and demagnetization magnetic field generation circuit |
| CN110797052A (en) * | 2019-10-21 | 2020-02-14 | 北京工业大学 | Rapid demagnetization method based on magnetic medium characteristics |
| CN111157924A (en) * | 2019-11-23 | 2020-05-15 | 重庆大学 | System and method for measuring and eliminating residual magnetic chain of three-phase transformer core |
| CN110911231A (en) * | 2019-12-23 | 2020-03-24 | 贵州振华群英电器有限公司（国营第八九一厂） | Magnetizing and demagnetizing method and device for magnetic latching relay with built-in three-pole magnetic steel |
| CN111816219A (en) * | 2020-07-09 | 2020-10-23 | 北京中超伟业信息安全技术股份有限公司 | Intelligent electromagnetic demagnetization system and method based on target identification |
| CN111816403A (en) * | 2020-07-09 | 2020-10-23 | 北京中超伟业信息安全技术股份有限公司 | Target position determining method and system for demagnetization |
| CN111816404A (en) * | 2020-07-15 | 2020-10-23 | 北京中超伟业信息安全技术股份有限公司 | Demagnetization method and system |
Non-Patent Citations (1)
| Title |
|---|
| 沈贺磊: "漫谈信息消除技术", 《电子设计技术》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112837705B (en) | 2022-05-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4019519A (en) | Nerve stimulating device | |
| US3947738A (en) | Pulsed power supply | |
| JP2599268B2 (en) | Method and apparatus for controlling current of motor winding | |
| JP4185123B2 (en) | Transfection control device sending high voltage current profile | |
| US4524412A (en) | Peak current controlled converter with additional current threshold control level to limit current tailout during overload conditions | |
| US4511829A (en) | Direct current control in inductive loads | |
| JPS62501673A (en) | Power supply with noise-free current sensing | |
| US4396879A (en) | Coupled series and parallel resonant circuit, in particular for electric fence apparatus | |
| EP0418074A2 (en) | Gradient current speed-up circuit for NMR system | |
| CN112837705B (en) | Demagnetizing method with magnetic field capable of being inverted | |
| US6621251B2 (en) | Phase voltage controlled voltage regulator of vehicle AC generator | |
| US3590358A (en) | Electronic battery charger | |
| US4178628A (en) | Switching type regulated power supply | |
| CN117833730A (en) | Underground damping generator voltage stabilizing system and control method thereof | |
| CN104781029A (en) | Electrical discharge machining apparatus | |
| CN106677946A (en) | Device capable of detecting operating point of electromagnetic valve armature of oil sprayer | |
| US5811953A (en) | Motor driving circuit and method | |
| US4256982A (en) | Electric pulse shaping circuit | |
| US3515969A (en) | Trigger circuit for inverter | |
| JPH01311864A (en) | Switching system stablizing electric source device | |
| JPH0993920A (en) | Dc high voltage power supply for capacitive load | |
| EP1514337A1 (en) | Method for fast-charging a battery and device for carrying out said method | |
| CA1173503A (en) | Direct current control in inductive loads | |
| RU2035744C1 (en) | Method and device for checking turn insulation of windings of electrical machines and apparatuses | |
| JP2599230B2 (en) | Charging device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |