INDICATOR DEVICE FOR CASSETTES LOADED WITH MAGNETICAL INFORMATION CARRIER

Abstract: Indicator device for cassettes loaded with magnetical information carriers, in which one of the faces of the cassette defines a window, an indicator block is located and guided for a sliding movement between at least two discrete fixed positions in the window, a positioning means is provided to fix the indicator block in said discrete positions, and the free surfaces of the window covered or uncovered by the indicator block are in respective planes with different heights so that the height difference can well be detected by appropriate detecting means.

Description: M INDICATOR DEVICE FOR CASETTES LOADED WITH MAGNETICAL INFORMATION CARRIER" BACKGROUND OF THE INVENTION The invention relates to an indicator device for casettes loaded with magnetical information carrier that can be the widely used standardized compact* . casettes for magnetic tapes, or specially designed casettes comprising flexible magnetical discs for information recording. Various types of indicator devices are already used on such casettes, and the information contents of these indicator devices can be read out by appropriate detecting mechanisms. On the rear edge face of the most commonly used standard compact casettes such indicator devices are formed by tabs which are cut out from the casette material at their fourth sides. Such tabs cover respective recesses in the casette body. When such a ' tab is removed, this will be detected by 'a mechanism in the tape recorder which prevents the recorded in¬ formation from being erased by blocking the recording mode of operation of the tape recorder. A similar indicator device is used in chromiumdioxid casettes for which special magnetical bias should be applied during playback and recording. In that case a recess is formed at the rear face of the casette that represents the information to be indicated (the Cr0 2 tape) , . nd this information can be read out in recent tape recorders to change the bias accordingly. It has been already proposed in the Hungarian patent 170.790 to load a flexible magnetical inform¬ ation carrier disc in casette, whereby an information recording system can be designed that is similar to the well-known "mini-floppy" system but it uses ca¬ settes and makes use of the advantages of casette technique. In this casette system there is a need of indicating several information which is charac¬ teristic to the casette and/or to the mode of record- * ing, etc. that can be read out automatically. The indicator devices (removable tabs) used in compact casettes have several drawbacks. First, the recording of the information associated with such devices is irreversible, i.e. final. After removal of the tab, the original condition cannot be adjusted, any more. This irreversibility is advantageous in many cases, but there are fields of applications, in which the possibility of changing the already set indicating information is required. The location of the indicator device in the rear edge face of the casette is also not advantageous, because the recorder/playback device should be design¬ ed with such sizes to be able to give room to. the detecting mechanism which has the task of reading the in ormation associated with the indicator device. This requirement is particularly unpleasant in case of front loaded casette decks, because thereby the minimum height of such decks is increased. For automation of recording and/or playback, of casettes, special casette stores are required that enable automated casette insertion in recorder and/ or playback devices. In such casette stores provision should be made for inhibiting the inappropriate in¬ sertion of the casettes in the store i.e. each casette should be loaded in identical, predetermined position in the store. This requirement cannot be' satisfied automatically by means of conventional case-ite designs. OBJECT OF THE INVENTION The primary object of the present invention is to provide an indicator device, by means of which the indicated information ean be stored with high stAbility, however, with the possibility of sub¬ sequent changes in the stored information content, and which has a simple and inexpensive constructional design and takes ew room from the casette volume. A further object of the invention is to provide a device that can simply assure, the always correct insertion of casettes loaded with flexible magnetical information carrier discs in casette stores. SUMMARY OF THE INVENTION According to the first aspect of the present invention an indicator device has been provided for casettes loaded with magnetical information carriers, ' in whic one of the faces of the casette defines a window, an indicator block is located and guided for a sliding movement between at least two discrete fixed positions in the 'window, a positioning means is provided to fix the indicator block in said discrete positions, and the free surfaces of the window covered or uncovered by the indicator block are in respective planes with different heights so that the height difference can well be detected by appropriate detecting means. According to the second aspect of the present invention a device has been provided for casettes loaded with flexible magnetical information carrier discs, in which one of the shorter side walls of the casette define a guide slot extending through the full height of the casette which is arranged asymmet- rically compared to the imaginary center line of the casette. The invention will now be described in connecti with preferable embodiments thereof, in which refere will be made to the accompanying drawings. SHORT DESCRIPTION OF THE DRAWINGS FIG. 1 shows the axonometric view of a standard compact casette comprising the indicator device according to the invention in its rear edge face; FIG. 2 shows the schematical axonometric view of a casette loaded with flexible magnetical information carrier disc, comprising the indicator device according to the invention on its upper face; FIG.3 shows the top view of the casette of FIG. .2; FIG. 4 shows the ^ side_view of the casette shq j vn in FIG. 3, partly in section; FIG. 5 shows the elevation view of the casette of FIG. 3; - FIG. 6 shows an enlarged axonometrical detail of a casette wall comprising a window for locatin the indicator device according to the in¬ vention; FIG. 7 shows an enlarged axonometric view of the sliding member of the indicator device according to the invention; and FIG. ■8 shows an enlarged axonometric detail of an inner casette wall supporting the sliding member of FIG. 7. DETAILED DESCRIPTION OF THE PREFERABLE EMBODIMENTS FIG. 1 shows a conventional compact casette wit OM a rear edge face, in which instead of the commonly used removable indicator tabs, a first embodiment of the indicator device according to the present invention is illustrated. The indicator device comprises a window 10 defined in the rear edge face of the casette, end an indicator block 11 located and guided in the window 10. ' In longitudinal direction the indicator block 11 is shorter than the window 10, preferably shorter than or at most equal to the half length thereof, and the block 11 can slide in the . window between two fixed end positions. In the position shown in FIG. 1 the indicator block 11 covers the left part of the window 10. In that case the free face of the indicator block 11 flushes with the plane of -the rear edge of the casette. The part of the window 10 which is uncovered by the indicator block 11 defines an indicator recess 12. The free bottom surface of the indibator recess 12 is sub- ' stantially parallel to the rear edge of the case r tte and it lies inwardly compared thereto. When the indicator block 11 is slid in the window 10 into the second fixed position, then the indicator recess 12 will be at the other (left) side • of the window 10. It can be seen, that the. relative position of the indicator block 11 and indicator recess 12 within the window 10 may carry information that can be detected by a suitable detecting means attached to the window 10. The indicator block- 11 defines depression 13 for facilitating its lateral movement. In case of a standard compact casette, the position of the indicator device can indicate the "further recording is allowed resp. inhibited" condition, a particular characteristic of the mag- netical information carrier (tape) loaded in the OMPI casette (e.g. CrO ? tape or normal tape), or any other information that can be significant when the casette is used. FIG. 2 shows a further way of application of the indicator device according to the invention. In that case the casette is loaded by a flexible magnetical information recording disc instead of the conventional magnetic tape, and_such disc is capable of storing information in a manner similar to the information storage in mini-floppy applications. FIG. 2 shows only those parts of such a casette that are important for understanding the present inventio In the largest free face surface of the casette, adjacent to one of its corners three indicator de- vices 20, 21 and 22 are shown located side by side t each other, and they are designed in the same way as the indicator device shown in FIG. 1. In the oblong-like windows indicator block 23 i located in a far position from the wide edge «f the casette, while indicator blocks 24 and 25 are in clo positions to the wide casette edge. The side by side arrangement of the three indicator devices is pre¬ ferable, because that can facilitate the design of the associated three detecting means (not shown) . The above described arrangement is ' preferable in vie of the applications of the casette, because if the indicator devices are arranged in the largest face of the casette, then the size of the recorder/playba unit will not be increased due to the presence of the detecting means associated with the indicator devices in the recorder playback unit. This can be understoo by considering the fact that the recorder/playback unit must be sufficiently deep in the direction norm to the largest face of the casette to accomodate the -casette drive and the recording/playback heads, and -7- this depth will not be increased by the presence of the detecting means associated with the indicator devices being generally smaller than the drive. It can be seen in FIG. 2 that one of the shorter side edge surfaces of the casette defines an out¬ wardly open guiding slot 26- being offset from the imaginary center line of the casette. Owing -to the asymmetrical location of the guiding slot 26 it will be possible "to insert such casettes, loaded with flexible magnetical information carrier discs, in a suitable casette_store. If in the casette store (not shown) an appropriate guiding rod is provided that fits in the guiding slots 26 of the casettes inserted in the store, then the casette insertion can be done only with a predetermined relative casette position with respect ' to the store. The guiding slot 26 is closed only from three sides, which is in contrast to conventional side indicating recesses that are closed from five sides, i.a*, they are open only from their faces. The presence of the throughgoing guiding slot 26 is preferable in case of automatic casette storage, because it enables the lateral sliding movement of the casettes in the store.. FIGs. 3 » 4 and 5 show ' further-de ails of the indicator device illustrated in FIG. 2. FIG. 3 corresponds substantially to the top view of the casette shown in FIG. 2. It can be seen in FIG. 4 that the casette has 1 a comparatively thick upper wall 30 in the region of the windows which is support¬ ed from below by a separate support wall 31. The indicator blocks 23, 24 and 25 comprise respective widened bottom parts which are guided between the upper wall 30 and the support wall 31* T e sectional view of FIG. 4 shows the open indicator recess of the indicator device 20 having a depth "d". When * the. associated indicator block is moved into its other position, the depth "d" will be practically zero. A typical value for the depth "d" is between about 2 - 2,5 mm which is sufficient for instrumenta depth detection.. FIG. 5 shows the elevation view of the guiding slot 26. It can be understood that the casette can be slid normal to the face plane if. a guiding rod (not shown) of a. casette store engages the guiding slot 26, which can facilitate automatic casette loading. FIGs 6, 7 and 8 show enlarged details of a pre¬ ferable embodiment of the indicator device according to the invention. FIG. 6 shows a detail of the upper wall 30 of a casette defining an oblong-like window 10. FIG. 7 shows, a slidable moving part,and the indicator block 11 is jumping out of the surface of the moving part. The indicator block 11 fits in the window 10. A wedge-shaped groove 15 extends across the bottom of.the moving part 14 in the middle regio thereof, and the left end of the moving part is pro¬ vided with a flanked edge 16, the angle of which corresponding to that of the groove 15. FIG. 8 shows ah enlarged detail of the support wall 31, on which a transversal wedge-like rib 32 is provided. If the elements shown separately in FIGs. 7 and 8 are combined in a casette as illustrated in FIG. 3, then in a first fixed position of the moving part 14 the groove 14 engages the rib 32, as in case of indicator devices 21 and 22 of FIG. 2. In the • other fixed position of the moving part 14 the flank edge 16 abuts to a corresponding flanking surface of the rib 32 that fixes the position of the moving par 14. If an appropriate tool (e.g. a tip of a screw- OMPI -9- driver) is inserted in the depression 13 of the indicator block 11, and sufficiently high sliding . force is applied on the tool, the support wall 31 will move away elastically from the upper wall 30 and the engagement of the moving 'part 14 gets released, whereby the moving part 14 can be slid in the other position. The engagement is, however, stable enough to maintain any set position of the indicator device through-a long period of time. The number of the indicator devices arranged beside each " other is determined by the requirements for indication being characteristic to the casette system. It is preferable, however, to provide room for additional indicator devices even if such additional devices are not required in given con- ditions, because technical development might increase later the need for indication. OMPI

Claims: ' -10- What is claimed is: 1. An indicator device for casettes loaded with magnetical information carrier, comprising a window defined in one of the faces of said casette, an indicator block located and guided in said windo for unidirectional sliding movement, a means for fixing said indicator block at least in two discret positions in said window, in which the face of said indicator block being in a di erent_depth than the bottom surface of said window part left uncovered by said indicator block. 2. The indicator device as claimed in claim l, which said face of said indicator block substantial flushing said casette face ' defining said window. 3 * The indicator device as claimed in claim 2, wherein said face of said indicator block defining a depression for insertion of a tool applying a sliding force. 4. The indicator device as claimed in claim 2, in which said indicator block having a length in sa direction of sliding movement being at most equal to the half length of said window in the same directio 5. The indicator device,as claimed in claim 1, in which said indicator block being built integrall with a moving part, said moving part fully covering said window and extending over the edges of at least two sides of said window below said casette face, said moving part defining on its rear face opposite to said window a transversal groove and a flanked edge, a support wall abutting said rear face of said moving part, said support wall comprising a transversal rib engaging respectively said groove and said flanked edge in said two discrete positions of said indicator block. 6. The indicator device as claimed in claim 1, in which said window being defined in the vicinity of a corner region of the largest face of said " ' casette. 7. The indicator device as claimed in claim 1, in which said window being defined in the rear edge face of said casette. 8.- A device 'for locating oblong-shaped casettes loaded with flexible magnetical information carrier disc, wherein a short side face of said casette defining a guiding slot extending through the full height of said casette, and said guiding^slot being positioned asymmetrically relative to the imaginary center line of said casette.

Inventors: JANOSI M
Applicants: BUDAPESTI RADIOTECHNIKAI GYAR
Application year: 1980
Main classification: G11B27
IPC codes: G11B5, G11B15, G11B19, G11B23