CN2222396Y - Demagnetising device for floppy disc - Google Patents
Demagnetising device for floppy disc Download PDFInfo
- Publication number
- CN2222396Y CN2222396Y CN 94221069 CN94221069U CN2222396Y CN 2222396 Y CN2222396 Y CN 2222396Y CN 94221069 CN94221069 CN 94221069 CN 94221069 U CN94221069 U CN 94221069U CN 2222396 Y CN2222396 Y CN 2222396Y
- Authority
- CN
- China
- Prior art keywords
- magnetomotive force
- floppy disc
- permanent magnet
- transport tape
- degausser
- 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.)
- Expired - Fee Related
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Abstract
The utility model relates to a demagnetizing device for floppy discs, characterized in that a magnetomotive force source is composed of a plurality of rows of rectangle permanent magnets; each row of permanent magnet arranges on a magnetic conductive plaque with the space that poles with different names are adjacent, which are insulated by a nonmagnetic material; an alternating magnetic field whose extent is from high to low gradually and equably is produced on the surface of a transmission strap along the operation direction of the transmission strap by adjusting the included angle between the magnetomotive force source and the transmission strap or adjusting the performance of each row of permanent magnet. The utility model has the advantages of simple structure, low energy consumption, low cost, reliable running, and ideal demagnetizing effect.
Description
The utility model relates to a kind of floppy disc degausser.
Demagnetization is one important procedure during floppy disc is produced, and its purpose is to eliminate the strong signal that writes when detecting in the floppy disc production process, avoids in use occurring error code.In existing Deperming Facility, simple in structure as the dc erasing machine of magnetomotive force sources with permanent magnetic material, it is little to consume energy, reliable, but with residual very big direct current remanent magnetism in the medium after this kind equipment demagnetization, be easy to generate dc noise, influence the record reliability of medium; With electromagnet as the AC erasing machine of magnetomotive force sources when eliminating tracer signal, can make medium be returned to magnetic neutral state, has desirable erasure effect, but need feed bigger electric current when using, not only power consumption is big, complex structure, cost height, and faults such as heating, sparking in use appear easily, influence the normal operation of equipment.
The purpose of this utility model just is to overcome the shortcoming of above-mentioned two class Deperming Facilities, provides a kind of simple in structure, and it is little to consume energy, and cost is low, and is reliable, and has the floppy disc degausser of desirable erasure effect.
Realization approach of the present utility model is: the magnetomotive force sources of degausser is made of the square permanent magnet of many platoon leaders, produces an alternating magnetic field on the transport tape plane of this magnetomotive force sources side thereon on the throne.In order to reduce the direct current remanent magnetism after the medium demagnetization, this magnetic field is adjusted to amplitude alternating magnetic field decrescence, promptly the entrance side at floppy disc is a high field intensity, reduces gradually along transport tape traffic direction magnetic field intensity, the magnetic field intensity of outlet side is reduced to insignificant degree.For reaching this purpose, the square permanent magnet of many platoon leaders is spaced on the magnetic conduction substrate in the adjacent mode of unlike pole, each is arranged between the permanent magnet and fills out with non-magnetic material.Magnetomotive force sources is positioned at the transport tape below, and the angle α between the two is 0～20 °.By adjusting the performance respectively arrange permanent magnet or adjusting angle α, as shown in Figure 2 the amplitude of producing on the transport tape surface by strong to weak alternating magnetic field.
Peak-peak field intensity that the utility model provides and minimum peak field intensity can be according to determining by the coercive force of demagnetization medium with to the requirement of direct current remanent magnetism.For guaranteeing abundant demagnetization, it is coercitive more than three times by the demagnetization medium that the peak-peak field should be.Permanent magnetism row's number is many more, and the peak value field intensity of outlet side is low more, and the direct current remanent magnetism after the medium demagnetization is more little.
The utility model is compared with background technology, has the following advantages:
1. compare with existing permanent magnetism degausser, direct current remanent magnetism is little, has desirable erasure effect;
2. compare with existing AC erasing machine, simple in structure, it is little to consume energy, and cost is low, and is reliable.
Below in conjunction with drawings and Examples the utility model is further detailed.
The structural representation of the floppy disc degausser that Fig. 1 provides for embodiment 1
Fig. 2 is the Distribution of Magnetic Field of upper edge, degausser transport tape plane transport tape traffic direction
The structural representation of the floppy disc degausser that Fig. 3 provides for embodiment 2
Among the figure: [1] is that permeability magnetic material substrate [3] is a transport tape for non-magnetic isolated material [4] for permanent magnetic material row [2]
Among Fig. 1, [1] is performance and measure-alike high-performance Ne-Fe-B rectangle permanent magnet, totally 20 arranges that permanent magnet unlike pole adjacent spaces is arranged on the high purity iron magnetic conduction substrate [2], [3] be the bakelite isolated material between the permanent magnetism row, they form magnetomotive force sources jointly; [4] be transport tape, the angle α between magnetomotive force sources and the transport tape is 20 °.Fig. 2 is the Distribution of Magnetic Field of transport tape surface along the transport tape traffic direction, and the peak-peak field intensity of entrance side is 240kA/m (3000Oe), and the minimum peak field intensity of outlet side is 5.6kA/m (70Oe).
With coercivity H is that the commercially available floppy disc of 58.4kA/m (730Oe) carries out the demagnetization test.Start the transport tape of degausser, floppy disc is put on the transport tape successively from entrance side, run to outlet side with transport tape and promptly finish demagnetization.
Table 1 has been listed this degausser and existing AC erasing machine and the DC degausser erasure effect to similar floppy disc.In the table, the method for testing of residual signal ratio is, at first writes 1F and 2F signal respectively with the floppy disk tests instrument on the inside and outside magnetic track of floppy disc, measures its average signal amplitude value; Then, with the corresponding residual signal mean value of measuring of floppy disk tests instrument, obtain the residual signal ratio then according to (residual signal mean value)/(original signal mean value) with the demagnetization as stated above of this floppy disc; Then the disc sample after a certain size the demagnetization of clip is directly measured its residual direct current remanent magnetism Mr (not adding magnetic field) and saturated direct current remanent magnetism Mrs (remanent magnetism of saturation hysteresis loop correspondence) with vibrating specimen magnetometer (VSM), obtains residual remanence ratio Mr/Mrs.From tabular language as can be seen, the degausser that the utility model provides, its erasure effect is better than the dc erasing machine, and is close with the AC erasing machine.
Table 1
| Degausser | Magnetic track | Residual signal than (%) (db) | Residual remanent magnetism Mr (kA/m) | Residual remanence ratio Mr/Mrs (%) |
| The utility model | Road in the outer course | 0.4 -48 0.4 -48 | 1.35 | 2.6 |
| The AC erasing machine | Road in the outer course | 0.4 -48 0.3 -50 | 0.3 | 0.6 |
| The dc erasing machine | Road in the outer course | 0.7 -43 0.5 -46 | 50.3 | 95.0 |
Among Fig. 3, magnetomotive force sources is made up of 20 different rectangle neodymium iron borons of row's performances and strontium ferrite [1], the descending even reduction of the Surface field of these permanent magnets, and be arranged on the pure iron magnetic conduction substrate [2] with the unlike pole adjacent spaces, each arranges between the permanent magnet isolated with bakelite [3]; Magnetomotive force sources is positioned at the below of transport tape [4], parallels with transport tape, produces and the similar alternating magnetic field of Fig. 2 along the transport tape traffic direction on the transport tape surface, and its erasure effect is identical with embodiment 1.
The floppy disc degausser that the utility model provides except the demagnetization that is applicable to floppy disc, also is applicable to the demagnetization of other digital magnetic recording medium.
Claims (2)
1. a floppy disc degausser comprises magnetomotive force sources and transport tape, it is characterized in that: magnetomotive force sources is arranged on the permeability magnetic material substrate [2] with the unlike pole adjacent spaces by the square permanent magnet of many platoon leaders [1], and each arranges between the permanent magnet isolated with non-magnetic material [3].
2. floppy disc degausser according to claim 1 is characterized in that: the angle α between magnetomotive force sources plane and the transport tape [4] is 0～20 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 94221069 CN2222396Y (en) | 1994-09-05 | 1994-09-05 | Demagnetising device for floppy disc |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 94221069 CN2222396Y (en) | 1994-09-05 | 1994-09-05 | Demagnetising device for floppy disc |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2222396Y true CN2222396Y (en) | 1996-03-13 |
Family
ID=33835478
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 94221069 Expired - Fee Related CN2222396Y (en) | 1994-09-05 | 1994-09-05 | Demagnetising device for floppy disc |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2222396Y (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102254666A (en) * | 2010-05-21 | 2011-11-23 | 宝山钢铁股份有限公司 | Magnetic density order descending array demagnetizing plate |
| CN102646496A (en) * | 2011-02-22 | 2012-08-22 | 宝山钢铁股份有限公司 | Method and device for demagnetizing steel wire conveying belt without energy consumption |
| CN103137283A (en) * | 2011-11-24 | 2013-06-05 | 江苏星火特钢有限公司 | Degaussing method and device in machining deformation process of austenitic stainless products |
| CN103208346A (en) * | 2013-04-10 | 2013-07-17 | 机科发展科技股份有限公司 | Magnetizing equipment for rotors of compressors |
| CN103310802A (en) * | 2013-05-14 | 2013-09-18 | 上海交通大学 | Secure destroying device for magnetic storage medium |
| CN103400586A (en) * | 2013-07-05 | 2013-11-20 | 中国电子科技集团公司第三十研究所 | Magnetic storage medium data destruction effect testing method |
| CN105118607A (en) * | 2015-09-29 | 2015-12-02 | 洛阳轴研科技股份有限公司 | Multi-pole-set integrated through-type demagnetizing device |
-
1994
- 1994-09-05 CN CN 94221069 patent/CN2222396Y/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102254666A (en) * | 2010-05-21 | 2011-11-23 | 宝山钢铁股份有限公司 | Magnetic density order descending array demagnetizing plate |
| CN102646496A (en) * | 2011-02-22 | 2012-08-22 | 宝山钢铁股份有限公司 | Method and device for demagnetizing steel wire conveying belt without energy consumption |
| CN102646496B (en) * | 2011-02-22 | 2014-06-04 | 宝山钢铁股份有限公司 | Method and device for demagnetizing steel wire conveying belt without energy consumption |
| CN103137283A (en) * | 2011-11-24 | 2013-06-05 | 江苏星火特钢有限公司 | Degaussing method and device in machining deformation process of austenitic stainless products |
| CN103208346A (en) * | 2013-04-10 | 2013-07-17 | 机科发展科技股份有限公司 | Magnetizing equipment for rotors of compressors |
| CN103208346B (en) * | 2013-04-10 | 2015-09-30 | 机科发展科技股份有限公司 | A kind of compressor drum magnetizing equipment |
| CN103310802A (en) * | 2013-05-14 | 2013-09-18 | 上海交通大学 | Secure destroying device for magnetic storage medium |
| CN103400586A (en) * | 2013-07-05 | 2013-11-20 | 中国电子科技集团公司第三十研究所 | Magnetic storage medium data destruction effect testing method |
| CN103400586B (en) * | 2013-07-05 | 2016-04-27 | 中国电子科技集团公司第三十研究所 | A kind of magnetic storage medium data destroying effect detection method |
| CN105118607A (en) * | 2015-09-29 | 2015-12-02 | 洛阳轴研科技股份有限公司 | Multi-pole-set integrated through-type demagnetizing device |
| CN105118607B (en) * | 2015-09-29 | 2018-02-13 | 洛阳轴研科技股份有限公司 | A kind of more magnetic pole group integrations pass through formula demagnetizer |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |