DE1474423A1 - Readout device for a magnetic memory - Google Patents

Description

Dr. Herbert Scholl Patent attorney A.ixDi'i--: iJ.V. Pü.LirS QLOEILAMPENFABRIEKEM

AxO: PHN- 501. HUI. 501

Registration dated May 17, 1965 'dJo / EB Unloading device for a magnetic storage device

The invention relates to a discharge device for a magnetic memory and in particular to a device for detecting a magnetic marking of a magnetizable carrier which is movable along a number of input and output heads in order to achieve a predetermined, mutual position between a magnetized point the carrier and an output head. Such a device can be used, for example, to sort out goods according to dimensions or claws. For example, a hola sorting device can be called Ea. Basically, sorting out takes place by means of a magnetic memory in the way that a magnetic marking is cut on a magnetic carrier at the moment when an object reaches a predetermined point on its conveying path, the magnetic carrier being connected to a transport device for the objects and the magnetic carrier being connected to a Marking on it is detected by means of a read-out head, which supplies a tilting pulse to a device which causes the object to leave the transport device when the magnetic mark has reached a certain point near the read-out head. Since the magnetic memory should be small , the device must be able to work with a high resolution of a few tenths of a millimeter when determining the relevant mutual position between the marking and the readout head. Ov are welter relatively large air gaps and high MagnetisierungflBtröme, no that the device mechanically strong and impervious en regen small changes in the air gaps and changes in MnfnetisierungBstrome and el? Newly found external Störfel.ier his muse. BATH ORIGINAL

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A device of this type is known in which the magnetic Marking of the carrier to the direction of movement, the carrier perpendicular and the position indicator is simply reversed by reversing the direction of the polarizing capillary is obtained.

This device has the disadvantage that and output head claims two magnetic tracks of the carrier and that the reversal point of the direction of magnetization on the Trägrr is indeterminate as a result of the fluctuations in the Air gaps and changes caused by the magnetization currents.

In the device according to the invention another type of marking is used, i.e. a magnetic point which is generated by a Kingabe head made with two side by side i'ol shoes which shoes will have different polarities at the bingale and are effective on the same bpur of the carrier. The entry is made during a short time interval so that the carrier can be viewed as stationary during input, whereby a magnetic point is generated, its orientation in the direction of movement of the carrier runs. These magnetic points, the direction of magnetization of which is essentially parallel to the surface of the magnetic carrier and runs in its direction of movement are often called magnetic longitudinal points. These places are generally used in data processing for storing data .digital information is used, whereby the presence of a place the number "1" and the absence of a digit the number "0" means. When reading a magnetic memory with these Difficulty arises in long spots, because it has been ascertained whether there is a magnetic carrier in certain places of the non-magnetic place there or not. The output takes place in the ..this that the magnetic carrier with a certain speed (length? of a dispensing head containing a detection coil which is guided by a magnetic flux originating from the magnetic base.

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The voltage occurring across the detection coil, which determines the output size of the output header is known to be proportional at the first time derivative of the detected flow. This is called dynamic readout because it is based on mutual movement established between the readout head and the magnetic carrier.

The Auelesekopf is usually of the same type as the pickup head and is therefore essentially sensitive to the longitudinal component of the magnetic flux from the site. The coil In this case, the flowing river changes over time, approximately similar to the original Sohreiblimpuls, so the output voltage of the readout head changes similarly to the first time-derived of the input pulse. Dien means a great distortion his Auepanpeimpulees compared to the original impulse. To remove this distortion, it has been proposed in association with the input head of the type described to use an Auerabe head that is sensitive to the magnetic flux that originates perpendicularly from the carrier. The first derivative of this perpendicular The flow, when the point passes the output head, changes over time approximately like the original input pulse, so that the original impulse through this output head practically is played back without distortion.

The present invention is based on the discovery that when measuring the perpendicular flux from a magnetic elongated point by means of a readout head, the output of which represents the magnitude of this perpendicular flux instead of a derivative, this output value can be used to determine the position of the magnetic point particularly precisely to determine. This type of readout, in which the output variable indicates the value of the detected flow at every instant, is known per se; it is often static readout /xenanr.t, since there is no r ^ r ^p r \ aei term movement between carriers

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and Ausleeekopf necessary 1st.

The invention is characterized in that reading a magnetic length a readout head is used, its detection direction almost perpendicular to the surface of the magnetizable The carrier runs, and which is connected to a device that displays the zero value of the magnetic flux component that originates perpendicularly from the carrier and thus from the Äusleeekopf. it is read that the aforementioned envelope indicator has reached the predetermined mutual position indexed

Since only the magnetic field component that is perpendicular to the wearer goes out, detected and the zero crossing of this field ' is used as a reference value for determining the position of the magnetic point in relation to the readout head, is very accurate achieved in the position indicator, even when using relatively large air gaps and high magnetizing currents. The location of the This is because the geometric configuration is the only way to achieve zero duration of the input headB independent of e.g. the air gaps and the input magnetizing currents Vedingt. To display the zero crossing To enable in a device according to the invention, the magnetic flux "must be detected statically, since the usual "Dynamic" readout does not contain any information with regard to the zero crossing would deliver.

The invention is described below in the accompanying drawing explained in more detail in the

Fig. 1 is a schematic view of a conveyor belt boy obeying goods,

Figure 2 schematically shows an end view of a storage drum for the conveyor belt according to Fig. 1,

3a schematically shows a view of an input head for use in the storage drum,

909828/1281 ^ original '

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Pig. 3b the pattern dee when using this Kingabekopfee preserved river lake,

Figures 4a and 4b show the corresponding views in use a storage drum with a premagnetized layer »

FIGS. 5a and 5b show a new read-out principle according to the invention;

6 shows a suitable embodiment of an input head »For use in a device according to the invention,

Fig. 7 shows the magnetization curve of a Hingkernee dee
Readout head and

Fig. 6 is a lock diagram of a circuit having this reading head »Own.

In Fig. 1, 1 denotes a conveyor belt for conveying objects 2, 3 in the specified direction from a loading point 4 to a number of unloading points 5 "6,7" connected to digits 5 - 6 and 7,
The sorting can be done by measuring the size of objects
same class or by class determination in the case of different types of objects.

The movement of the objects on the belt is recorded in a memory (see Fig.?), Which consists of a drum with a magnetizable layer and is coupled to the drive of the belt, 80 so that the drum rotates synchronously with the belt. The drum works with a number of riingabeköjjfen 9 and a number of
Read out heads 10, 11 and 12 agree. The input heads are arranged at a small distance from one another in the axial direction and each define a magnetic track on the magnetic drum. The leeward heads

are also arranged in the axial direction so that they each have a separate

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Scan the other M; i £ net track.

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The outfeed heads are furthermore arranged at different points along the circumference of the trone, which points are chosen such that the distance between stations 9 and 10 on the 'flow tube corresponds to' distance between 4 and 5 on the belt '. The distance between 9 and 11 corresponds to the distance between 4 and 6, etc. When an object is brought onto the belt at station 4, a short singing pulse is fed to one of the kingnbe heads. The measurement of the size of the size determination of the object placed on the stent or the selection of the information head to be excited, or the selection can be made beforehand, if the size measurement or determination of the clan provides the information that the object is at the. station is to be unloaded, the cüi. ^ ate head is excited, which interacts with the same opure as the luslesekopf 10. When the object is to be unloaded at the! station b , the i ^ ing head, which is driven with the same opur how the readout head 11 interacts, etc. During the movement of the object over the path, the magnetic point of the drum moves accordingly and when the object reaches the readout point, the magnetic point also reaches the readout head which detects the magnetic track in question. The Aaslesekopf then generates a Kippimpuls, which is fed to a device, the object lie voranlusst, -IAS country for the Next-'befördorun / ¹ 'in a :: ugehörenden 5peichf! Rrnum o. To leave the like..

If the number of remote stations is large , a reduction in the number of tracks on the drum can be excited by a number of kings at the same time. A \ ei must of course correspond to eiiiR; henle the number of Äur.lene heads intended for every blade attachment.

Der hlingabeimpulsgebor int s ;; hemat iticn in .'if. J5a shown; I ^ and Ib denote the ^ wei folschuhe de * A ^^ t "head

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and 17 denotes the magnetizable oil on the drum. the The drum can move in the direction χ. When entering a, magnetizing connected to the pole pieces of the input head Winding energized, so that during a short time interval the Pole shoes form magnetic poles of opposite polarity, whereby a magnetic flux is generated according to the plus lines in the drawing. The magnetic flux can be in a component in the direction of movement of the drum, or x-direction (B) and in a component perpendicular to the drum surface, or y-direction (B), the

Function of χ can be graphed so that the curves of Fig. 3b arise. Since the magnetic layer is permanently magnetic, a magnetic point remains on the carrier Termination of input circpulseu. This magnetic otelle has one Magnetic field strength on the surface of the magnetic layer accordingly the B -B curves. B has the same polarity over the entire magnetic field Place and the maximum lies at a point, which is conditioned by the symmetry line of the Ein ^ ubekopfes in the input moment, while Bn passes through zero at this point and has different polarities on either side of it.

If the magnetic point by means of a usual

Ausleaekopfcs is scanned, which is almost the same design as the Input head, an overvoltage is generated in the detection winding of this Auelesekopfes induced approximately in accordance with the B curve according to Fig. 3 The maximum is evidently never enough and therefore not suitable for me ila 'reference for the La ^ e 1er magnetic point. Ea is not either possible to get a precisely defined reference of the position, if as a reference z.l. a point is used where the magnetic r'luas exceeds a predetermined level.

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According to the invention, a readout head is used that only dm. scans the magnetic field emanating vertically from the magnetic drum and which supplies a voltage that is almost equal to the curve B In Fig. Jb when passing the magnetic point along the readout head follows. The zero crossing of the B field bat exactly determines the position and

y ■

is therefore used as a reference when reading out. A suitable tilting impulse is generated when dna B field has a small negative value after has reached zero continuous gear. However, that B-FtId is also beyond the magnetic point Mull uqd to avoid that Generate small dither fields tilting impulses, the magnetic Schioht suitably premagnetized according to Fig. 4 "

Fig. 5h shows the signal voltage e which is sensitive to that for B « aWBleeekopf 18 (Fig. 5a) is removed when a magnetic position Smell Fig. 4 runs along this head. The Auelesekopf 18 is involved eleventh * element 19 together, which generates a tilting impulse, which e.g. • an ejection mechanism in the conveyor belt 1 is fed when (Let signal voltage β a predetermined, low visual threshold value naob Aarita'tsKhang has reached, the magnetic body is suffering in

Orientation of the magnetic layer during the movement according to the drawing and fin · - 5 * «means that the signal voltage curve runs close to the reading head. Fig. 5 »shews the Augenbllok, i% dit the signal voltage the predetermined Schwellwtrt according rVlaritMteSnderunfr has reached and thus the Augtnbliok, is generated in the tin IClffilmpule.

The Auelesekopf 1Θ can, for example beatehtn from a Sieankern who did surrounded by a fioklung and mounted perpendicular aohipht to the äohieht einceordnet let and from which 'a iSnde close to the · 9s eiftnlcern is then traversed by a Magnetfluaa entepreehend the i · W »H . If no special precautions are taken,

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provides the voltage induced in the winding but only the temporal changes of the flux dar (dynamic detection) ι Ub Obtaining a static reading of the B field becomes a periodic Change of the permeability of the iron core carried out! di · basically is caused by "a periodic change in the magnetic state" of the nucleus. In a preferred embodiment of the reading head, according to the invention according to FIG. 6, the iron core the Fora of a toroidal core 2 t, which is completely controlled by the scanning coil 20 is surrounded and with x two series-connected excitation coils 22 and 23 is provided. The toroidal core 21 is made of a material with the Magnetieierunirakurv · after Fiß. 7. The change in permeability is obtained in that the core is driven alternately in one and in the other direction into the saturated state, e.g. through periodic switching of the core between points 24 and 25 in the aiu ^ netization curve. The hanging core 21 is attached in such a way that that its surface is perpendicular to the magnetic layer to be scanned. The symmetrically arranged excitation coils 22 and 23 act together to generate magnetic flux through the core, while the magnetic fluxes of the coils 22 and 23 oppose each other with respect to the flux sensed by the sensing winding 20. the Coils 22 and 23 have an equal number of turns and are Balanced exactly in such a way that practically no voltage is induced in the winding 20 when the core is switched in the absence of an external field will.

The external dimensions of the readout head are very small, e.g. a few millimeters, so that in practice the magnetic layer is scanned point by point.

The solution after. Fig. Θ ^ m excitation of the Ausleeekopf and for estimating output voltage, the output voltage includes a crystal controlled oscillator 30, for example at a frequency of

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50 IcHa. The oscillator carries its output voltage one Frequency halving device 31 to which the / oiregeapulen des. Auelesekopfee feeds via a resistor H. The tension of the * Sampling winding 20 of the readout head is connected to a low-pass filter 32 » da «to twice the switching frequency z.E. 50 kHz tuned and is further fed to a phase rectifier 33, the reference voltage of which is supplied by the oscillator 30.

The mode of operation of the device is based on the known «phenomenon that an iron core, which is supported by an external, static magnetic flux and is switched between different magnetieation states at the same time, in every instant ▼ on a magnetic flux is traversed by the Husseren, static Magnetic flux is created, which is the instantaneous permeability of the Kernes corresponds.

; The iron core? 1 with the magnetization curve according to Fig. 7 therefore, an external F is generated twice per cycle of the switching voltage Fluns (when the perpendicular parts of the magnetization curve pass through are) "absorb" and twice per period a uzoren B flow

'. . -Ji

(when passing through the horizontal parts of the fca / jnetieierun ^ skurve)

· ■ · ■■ "*

ßbstoasen. As a result, there is tension in the winding 2C induced, which is dependent on the 1 -flow and the double value of

S; ch.al'tfrequency has. The output voltage of the winding 20 contains in addition, a large amount of harmonics and possibly also a small component with the switching frequency. These components are however, screened out in the filter 32 and the output voltage of this filter is a V / echselopannun ^ with twice the Schillt frequency. The amplitude the alternating voltage is approximately proportional to the external, etatic Dy-PeId and the phase depends on the direction of this field away. The phase rectifier 33 with the signal voltage of the filter 32

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Reference voltage of the oscillator 30 supplies a in a known manner DC voltage proportional to the amplitude of the signal voltage ' and has a polarity that depends on the phase relationship zwtaohen depends on the signal and reference voltage. The phase rectifier will thus in this case deliver a voltage which is approximately proportional to the size of the B flux, while its polarity depends on the direction of the river.

For detecting the zero crossing of the E field and for Generation of a Kippinpulseo for an Auawerf Mechanism in the Traneportbahn the device 34 is connected to the output of the PhaDengleiohrichtere. i) The device 34 contains amplifier means and Discriminator ^ leather for generating a tilting impulse when the voltage of the rectifier when reading out a magnetic point the aforementioned * rt to a predetermined, low threshold value after the passage of the gauze and the change in rarity.

It is also advantageous to use a reading head with a Hall element for scanning the Ii field. Small Hall elements are available, which are attached close to the magnetic carrier, so that they lie in a plane running parallel to the carrier surface. In this case, the magnetic circuit and the fiber contact winding can be omitted, so that a very simple Ausleoekopf is obtained. One advantage of a Hall element as for the fluesenpfindlich.es element is that, in contrast to the described uuslene head, this element does not influence the magnetic flux from the wearer. However, there is a disadvantage in that the output designnl of the small Hall duck will necessarily be small.

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Claims (8)

- 12 - PHI. 501 1. Device sun laying out a magnetic marker of a magnetisable carrier, which is movable along input and output heads »whereby the achievement of a predetermined, mutual Position between an output head and a magnetic point on the carrier is indicated, which point is indicated by means of a Bingabekopf • * ■ it is created with two magnetic poles that are in the direction of movement of the carrier lie one after the other and the different during the input The polarity of the device contains a read-out head (18) whose detection direction is almost perpendicular to the surface of the magnetizable carrier (17) and the bit of a member (19) is connected to display the pen value of the magnetic flux component, which comes vertically from the carrier and from the reading head is measured so that the attainment of the Yorherbestieatten, mutual Location is indicated by the XuI! Value specification. 2 · Device according to claim 1, characterized in that the Ausleeekopf a magnetic circuit to · generate the magnetic flux component for the Contains magnetic flux component originating from the carrier, which circuit is at least partially surrounded by a Abttistwioklung (20) and with Links is connected by which the permeability of the magnetic circuit or a part thereof is periodically changed, the in the Detachment through the change in fluff as a result of the periodic Permeability change generated tension for the size and the direction the scanned flow component is decisive. 3.Vorrichtung according to claim 2, characterized in that the magnetic circuit has the shape of a king core (21), which is derived from the Abtaatwioklung (20) is surrounded, the members for periodic change of the Permeability contain two excitation coils (22, 23), which are symmetrical attached to the toroidal core and connected to an AC voltage source are wrapped around the core alternately in one direction and the other in the 909828/1281 - 13 - OT. 501 To drive satiety. 4.Vorrichtung according to claim 2 or 3 »characterized in that the Sampling winding (20) with the signal input of a phase rectifier (33) is connected, whose Eezugeepspannung from a generator (30) originates, which is effective with twice the frequency of the voltage to periodically change the permeability. 5 · Device according to claim 1, characterized in that the readout head contains a Hall element which is attached to the magnetizable carrier (17) in a plane parallel to the surface of the carrier is. 6.Vorrichtung according to any one of claims 1 to 5 »characterized in that that the element (19) for displaying the zero word of the flow is a signal can generate when a predetermined, small Üvoltage value after dom zero crossing is reached. 7.Vorrichtung according to any one of claims 1 to 6, characterized in that that the magnetizable carrier (17) aenkreoht in one direction 3a surface is pre-machined. 8.Sorting device for sorting out objects by means of a Device according to one of Claims ΐ to 7 »which objects are conveyed via a conveyor belt, characterized in that a number of readout heads for sensing the magnetic flux component is provided, which originates vertically from the carrier, which readout heads at different readout stations (1O, 11, 12) along the carrier are arranged according to different unloading stations (5 »6, 7) along the conveyor track and interact with ejection mechanisms, which are arranged at the abledestutionen mentioned and dl depending on the signals sent by members (19) to «displays the value of the fluence component perpendicular to the carrier (17) can be operated. BAD ORIGINAL, χ 909828/1281