CA1191948A - Magnetic disk cartridge having record track indicating means - Google Patents

Abstract

MAGNETIC DISK CARTRIDGE HAVING RECORD TRACK INDICATING MEANS

ABSTRACT OF THE DISCLOSURE

A magnetic disc cartridge having a jacket which contains a rotatable magnetic disk of the type havinhaving a hub member which receives a rotatable drive shaft which rotatably drives the magnetic disk. The cartridge is comprised of a jacket having an opening therein through which the rotatable drive shaft passes. When the disk is rotated, information may be recorded in a plurity of circular tracks thereon.
The disk also is provided with an indicator for indicating the number of tracks in which information signals already have been recorded.

Description

B~C~C-RoU~D OF TE-Ir I V TNION
This invention relates -to a magnetic disk cartridge and~ more particularly, -~o such a cartridge which is formed of a jacket in which a rotatable magnetic disk is housed, the cartridge being used in recording/reproducing apparatus of an electronic still camera and the jacket being provided with an indicator to indicate the number of still "pictures"
which have been recorded.
Rotatable magnetic disks have been used for recording information in various types of devices. For example, in computer systems, word processers, and the like, magnetic disks, known as "ais]cettes", have been used to record information signals. Typically, such diskettes are housed in a jacket which serves to protect the magnetic information recording surfaces of the magnetic disk and, furthermore, to prevent the magnetic disk from being folded, crumpled or otherwise seriously damaged. Such a protective jacket is provided with a window through which one or more magnetic transducers may be inserted to magnetically contact the magnetic surface of the disk for recording or reproducing information signals thereon. Such information signals are recorded in a plurality of circular recording tracks.
In a magnetic disk of the aforementioned -type, there is no indication on the jacket or disk-housing apparatus for opposing a user of the number of tracks on which information signals have been recorded. Typically, this infiormation is zenerated by the recording apparatus which may keep account of those tracks which have been used as well as -those track which are available For subsequent recording. In most inEormation recording sys-tems, however, the user is not apprised of t:his accounting information and, -thus, may not be aware of t:he actual recording capacity which has been consumed or which remains available.

OBJI.CT~ OI;~ Tl~ IN~E~TION
There~ore, it lS ;In o~ ject of the presen-t invention to provide an improved magnetlc disk cartridge having an lndicator thereon which directly apprisesa user of the recording capacity of the magnetic disk which has been consumed and/or which remains available for further recording, Another of -the object of this invention is to provide an improved magnetic disk cartridge having a jacket on which -the aforementioned indicator is provided.
A furtner object of this invention is to provide a magnetic disk cartridge having a jackec which contains an indicator that directlyapprises a user of the number of tracks on the magnetic disk in which information signals have alre-ady been recorded.
An additional object of this invention is tc~ provide a maqnetic disk cartridge having a jacke-t which contains an indicator that is of relatively simple constuction, is easily manufactured and operates in a simple manner to appriseauser of the number of tracks of the magnetic disk on which information signals have been recorded.
Various other objects, advantages and fea-tures of the present invention will become readily apparent from the ensuing detailed description, and the novel fcatures will be particularly pointed out in the appended claims.

i~ U~M ~Y O F' T~l C, 1 NV_N T I ON
In accordance with this invention, a disk cartrige is provided for houslngarnagne-tic disk -therein, the latter beingof the type having ahubwhich is adapted to receive a rotatable drive shaft and thereby rotate the magnetic disk so that information signals may be recorded on individual circular tracks. The cartridge is formed of a jacket which surrounds and protects the magnetic disk, and \
\ includes an opening through which the aforementioned drive shaft may pass so as to be received by the hub of the magnetic disk. The jacket also is provided with an indicator which gives a direct indication of the number of trac]cs in which information signals already have been recorded. The indicator thus provides an indication of the amount of recording capacity of the disk which has been consumed or, alternatively. which remains for further recording.
In accordance with one aspect of this inventlon, the information indicator is comprised of a dial and an index scale, the latter being provided with markings which indicate the number of tracks which may be recorded on the magnetic disk. The dial and index scale are relatively movable with respect to each other; and the dial includes a pointer which is adapted to point to successive track number markings on the index scale.
In on~ embodiment of the present invention, the dial is rotatable and includes a recess for receiving a drive pin associated wit:h the recording and/or reproducing apparatus in which themagnetic disk cartridge is used. This recess serves not on]y to rotate dial as the drive pin rotates but, in addition, also function as the aforementioned pointer.
In a speciic e~bodiment of this invention, the dial is mechanically coupled to a gear member, and a releasable locking device is insertable between adjacent teeth of the~gear member so as to releasably lock the dial in any particular angular position that is then present. The dial is released when it is rotatably driven,thereby permitting succ~ssive teeth on the gear me~er to pass the locking member. Preferably, the releasable locking member is in the form of a :- resilient pawl which is ecured to an inner surface of the ~acket.
~lorc pa~ i~ularly, there is pro~rided:

A magnetic disc cartridge of the type having a jacket for containing a rotatable magnetic disc therein, ~aid disc having a hub member for receiving a drive member to rotate said disc to record inEormation in circular tracks on said disc and comprising an opening in sald jacket through which said hub member is accessed; and externally accessible indicator means provided on said jacket for indicating the number of tracks in which information has been recorded by incremental rotation.

BRIEF DESCRIPTION OF THE DRAWINGS
The following detailed description, even by way of example, will be best understood in conjunction with the accompanying drawings in which:
Fig. 1 is a plan view of the jacke~ or cartridge containing a flexible magnetic disk, which is shown partly broken away;
Fig. 2 is a plan view of the jacket or cartridge sh~wn on Fig. 1, b~t as viewed from the opposite side thereof;

Fig. 3 is an enlarged sectional view taken along the line 3-3' on Fig. l;

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Fig. 4 is an enlarged fragmentary top plan view of the j acket in which the top wall i 8 removed;
Fig. 5 is an enlarged sectional view taken alorlg the line 5-S ' on Fiyn 4;
Fig. 6 is an enlarged fragnnentary top plan view of the ~acke~, in which the top wall is removed and wherein an indicater driving pin is inserted into an apertur~ ~hereof; and Fig. 7 is an enlarged ~ectional vlew taken along the line 7-7 ' on ~ig . 6 .

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li91~ 3 DETAILED DE~SCRIPTION Ol;` A PREFERRED EMBODIMENT
Referring now -to the drawings, wherein like reference numerals are used throughout, and intially to Figs. 1, 2 and 3, it will be seen that a cartridge 1 intended for use in a flexible disk recording and/or reproducing aparatus comprises a substantially flat rectangular jacket or housiny

2 which may be molded o-E a sui-table plastic and has opposed walls 2a and 2_ between which a :flexible disk 3 of magnetic material is freely rotatable. Disk 3 is of a suitably small diamete~, for example, no more than about 50 mm, so that jacket 2 can be of correspondingly small size, for example, m~asuring 60 mm by 54 mm by 3 mm, for conveni.ence of handling, storage and shipping, as by mail, and for use in a very compact recording and~or reproducing apparatus which may, for example, be part of a still picture camera which i.s not substantially larger than a conventional 35 mm single-lens reflex camera. Opposed walls 2a and 2b of jacket 2 have aligned openings or windows 4 therein which extend, in the radial direction of disk 3, at least tQ the inner and outer effective limits O.f circular recording tracks, of a recording surface 3a on the disk. A door member 5 strad-dless ~isk 3 and is slidable along an edge portion of jacket 2 with portions of door member 5 disposed against the inner surfaces of walls 2a and 2b for slidable movement in the direction of the arrow 5a on Fig. 1 from the illustrated closed postion to an opened position in which door member 5 clears windows 4. A tension spring 5b may be connected to door member 5 for urging the lat-ter to its closed position, and a projection 5c extends from door member 5 and may be acted upon by a sui-table member provided on __. /

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the apparatus which receives cartridge 1 in the camera (not shown) for opening door member 5 upon the insertlon of cartridge 1 into -the recording and/or reproducing apparatus. ~hen door member 5 is thus opened, one or more magnetic heads can extend through one of the windows 4 for magnetically recording info:rmation signals, for example, representing a still imag2 or p:icture, in a selected one of concentric circular record tracks on surface 3a (E'ig. 3) of the disc.
A hub 6 is provided at the center of disk 3 and has a hole 7 extending therethrough for receiving a drive shaft (not shown) of the recording and/or reproducing apparatus. The hole 7 is preferably non-circular so as to define a pair of relatively angled positioning surfaces 8 adapted to tangentially engage the circular periphery of the drive shaft for centeriny rotary disk 3 relative to the axis of the drive shaft. A resilien-t chordal element 9 extends across hole 7 at the side oE the latter opposite positioning surfaces 8. Such Chrdalelement 9 is backed up by an elongated hole 10 extending along element 9 at the siae of the latter opposite that surface 9a thereof which Eaces toward positioning surfaces 8. The described hub 6 can be easily molded of suitable plastic material which Eurther lends elasticity to the resilient element 9. The hole 7 is dimensioned so that, when the drive shaft is inserted therein, resilient element 9 is flexed in the direc-tion away from positioning surfaces 8 by the shaft, whereby to maintain firm con-tact of surfaces 8 with the outer periphery of the drive shaf-t.

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Hub 6 is fur-ther shown to have an annular magnetic member l:L sultably mounted on its lower surface. A magnetic detecting pin 13 for use in de-tecting the ro-tational phase or position of disk 3, and a non-maynetic balancing pin 14 of substantially the same weight as pin 13 are embedded in hub 6 at diametrically opposed locations. In one embodiment, at least three supports or feet 16 extend from t.he lower surface of hub 6 at equally angularly spaced apart locations which are radially outward in respec-t to annular magnetic member 11. The bottom surfaces 16a of supports 16 projec-t slightly from the underside of hub 6 and define a reference level with respect to the magnetic recording surface 3a of disk 3. In ano-ther er~odiment, feet 16 are repla ed by a continuous annular rim. Walls 2a and 2b of jacket 2 have central openings].7a and 17b in which hub 6 is loosely rota-table~
In accordance wi-th the present invention, jacket 2 of cartridge 1 is provided with an indicator 20 which is adapted to di.splay an indication of that portion of the capacity of the disk 3 whi.ch has been c.nsumed or, al-ternatively, at position of the capacity of the disk which remains available for further recording. More particularly, indicat r 20 provides an .indication of the number of tracks in which information signalshave ~isplays been recorded on the disk. From Ei and 2, i-t is seen that the indi.cator in ludes a rotatable dial 21, and index scale 28 circularlyarranged about dial 21, and a pointerassociated with the dial and adapted -to point -to an :indication on the index scale which represents the number of tracks which have been recorded on the desk 3.
In th~ illus-trated embodiment, d:ial 21 is adapted to rotate with respect to index scale 28.

In an alternative emb~diment, the index scale may be provided on the rota-table dial and, -thus, may be rotatable with respect to a pointer that is fixedly disposed on the jacket 2. It is appreciated, therefore, that dial 21 and index scale 28 are relatively rota-table with respect to each other.
Preferably, as illustrated in Fig. 1, index scale 28 is provided wi-th markings orindicia which provide a numerical indication of the number of tracks which have recorded on thedisk. ~s one example, disk 3 may be provided with a recordiny capacity of the order of 50 tracks.
Hence, index scale 28 is provided with numerical indications from track 1 to track 50. Suitable marks or gra~ations may be provided between the discrete numerals indicated in Fig. 1. Such marks may represent every track, every other track, or the like.
Jacket 2 is provided with a further aperture 27 through which dial 21) for example, may be accessed by a compa~ible drive mechanism, described below. Dial 21 is positioned within the space defined by spaced apart top and buttom walls 2a and 2b, and is adapted to rotate therein. The pointer described below with respect to Fig. 4 may be observed through opening 27a in top wall 2a, and the dial itself may be driven by a suitable device which engages the dial through an aperture 27b in bottom wall 2b.
~ s bes-t shown in E'igs~4 and 5, dial 21 is mechanically coupled to a gear member 24, the latter being provided with teeth about the periphery thereof. In the preferred embodiment,dial 21 and gear member 24 are of unitary construction formed of a suitable plastic.

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Alternatively, gear memher 2~ may be coupled, as by a suitable mechanical transmission,to dial 21.
In one embodiment wherein the dial and gear member are of unitary construction, the gear member is formed sy~me-trically with respect to the dial such that equal portions of the dial are disposed above and below the gear member, as shown ln Fig. 5. The dial may be thought of as the central hub of the gea~ member. In the embodiment shown in Fig. 5,-t~le top and bottom surfaces of dial 21 are stepped respectively so as to be seated within apertures 27a a~d 27b of top and bottom walls 2a and 2b, respectively. In an alternative embodiment, the stepped portions may be omitted, whereupon the upper and lower surfaces of gear 24 seat on the inner surfaces of the top and bi~ttom walls of jacke~t 2, respectively, whereupon dial 21 is positioned wi-thin apertures 27a and 27b.
A releaseable locking device 25 cooperates with gear member 24 to lock the gear member and, thus, dial 21, at the then-present position of the ~ial. As will be described~
dial 21 may be rotatably driven by a suitable drive mechanism provided in the recording and/or reproducing appara-tus with which the magnetic disk cartridge is used so as to update the indication provided by pointer 23 as the number of circular tracks in which information has been already recorded increases.
Dial 21 is rotated in a step-wise manner; and releasable locking device 25 serves to retain the dial at the last position to which it has been rotated. I'his enables the magnetic disk cartridge to be removed frorn the magnetic recording and/or reproducing apparatus while retaining the proper indication of the :Last track which has been recorded immediately prior to -the removal thereof. That is, dial 21 is restrained from inadvertent rotation when the magnetic disc cartridge is handled, stored or shipped.
In the illustra-ted embodiment, releasable locking device 25 is formed of a resilient pawl 25b which terminates in a nose 25a that is insertable be-tween adjacent teeth of gear member 24. Pawl 25b is formed of unitary construction with a mounting block portion 25c, this mounting block portion and the pawl being informed of a suitable plastic. As illuststrated, pawl 25b depends from mounting block 25c. The mounting block is adapted to be mounted on the inner surface of, for example, top wall 2a of the jacket. Suitable mounting elements, such as screws 26, may be used. Alternatively, mounting pins may be ~ormed integrally with the inner surface of the top wall of jacket 2 and mounting block 25c includes suitable apertures which register with such mounting pins such that the mounting block is mounted by a pressed fit.
The resilie~t pawl 25b urges nose 25a into engagement with the teeth of gear member 24. As the gear member is rotatably driven (to be described), the movement of the teeth thereof flexes pawl 25b so as to temporarily remove nose 25a from be-tween the teeth. As will be descrlbed, dial 21 is rotated so as to correspondinyly rotate gear 24 by which if passes one tooth past nose 25a~ After this passage of one tooth, nose 25a once again in inserted between adjacent teeth of gear member 24. Thus, dial 21 is rota-tably advanced by an angular distance equal to the angular separation bet:ween adjacent teeth of the gear member upon I
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-the recording of a si.ngle circular track on disk 3.
After the next track is recorded, dial 21 is driven to once again advance the gear member by this amount, and pointer 23 is stepped to indicate the number of tracks in which informa-tion signals have been recorded.
As illustrated in Fig. g 7 aperture 22 of dial 21 is keyhole shaped, whereby pointe:r 23 is formed by a recess or elongated notch portion of this aperture. That is, pointer23 is formed of an extension of aperture ~2, the latter being referred to herein as a recess. The purpose of this recess will best be understood by reference to Figs.6 and 7.
When magnetic disk cartridge 1 is loaded into a suitable holder (wnich.lsnot shown)of the magnetic recording/
reproducing apparatus, a drive shaft 30 having a radial projection 31 is inserted into aperture 22. As best shown in Fig. 6, projection 31 is received by . recess 23. Drive shaft 30 is partially surrounded by a collar, or sleeve 32.
Drive shaft 30, together with projection 31, is adapted to be moved in the a~ial direction thereof, or the vertical direction as viewed in Fig. 7. Thus, drive shaft 30 i:s movable with respect to collar 32. ~s will be explained, this axial movement of the drive shaft permits proper registration of projection 31 wi-th recess 23. Once the proper registratlon has been obtained, the recording/reproducing appara:tus is energized to ro-tate disk 3 and record information signals in a :respect.ive track thereon through window 4.
I'he magnetic head o:~ the recording/reproducing apparatus is mechanically :Linked to drive shaft 30. The posi-tioning of this magneti.c head on a respective track of disk 3 is effected ~L~

when projection 31 is insertecl into recess 23~ Then, as drive shaft 30 rotates~ -the mechnical linkage to the magnetic head serves to radial.ly change the position of that head so as to record another track on the disk.
Therefoxe, for proper recording, projection 31 should engage recess 23.
In a recording/reproducing appara-tus with which the magnetic disk cartridge is used, drive shaft 30 normally is biased to an initial circumferential or.angular position whereby projection~31 is opp~s]te a "O" indication on index scale 28. If~ however, one or more tracks have been recorded on thelmagnetic disk contained within the magnetic disk cartridge that is inserted into tha-t recording/
reproducing apparatus, recess 23 inti.ally would not be in registration or alignment with projection 31 and thus, when the magnetic disk cartridge is loaded, dial 21 contacts projection 31 so as to depress drive shaft 30 within cQllar 32. This depression of the drive shaft serves to actuate a drive motor whereby collar 32 is driven -to rotate drive shaft 30 and projection 31 and also to advance the magnetic head from one track to the next along disk 3. When the drive shaft 30 has been suitably driven so as to position projection 31 in alignment with recess 23, an up ward spring-bias exerted on -the drive shaft permits the projection to be inserted into the recess and thus deactuate the aforementioned drive motor. Consequently, the projection 31 now is in proper driving engagement with the di~l21 and, moreover,-the magnetic head is positioned opposite the proper -track on ~i.sk 3. A recording operation now may commence~ At the .
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completion of -that recording operation, the collar 32 is driven by the af~remen-tioned drive motor so as to rotate the drive shaft 30 and the projection 31, thereby advancing the dial 21 such that recess 23 now points to -the number of the last track which has been recorded. Also, the magne-tic head is advanced so as to be positioned to record the next track on magnetic disk 3.
It should be recognized that collar 32 is ro-tatably driven by an angular distance which corresponds to the angular separation betweeen the adjacent teeth of the gear 24.
Hence, dial 21 is rotated by a unit increment after -the track has been recorded. Preferably, this unit increment i.s proportional to the indication on the index scale 28 of a single track. That is, the angular distance between the angular teeth of the gear 24 is proportional to the angular dis-tance between indications on theindex scale 28, thereby providing incremental step~wise indications of the number of tracks which have been recorded.
From the foregoing description, it is recognized that recess 23 of dial 21 functions not only -t.o receive projection 31 of the dirve shaft 30 but, also, to indicate the number of tracks which have been recorded on the di.sk 3.
The dial 21 rotates in an incremental, step-wise manner by an angular distance which corresponds to an increment on index scale 28. Moreover, the linkage between drive shaft 30 and the maqnetic head Eunctions to prevent recordi.ng until yrojecti.on 31 is in engagement with the recess 23. This pre-vents the recording on the same track of new information ~ ~Lsg~.~3J~ / r-which woulcl des-tory the informcltion which had been xecorded previously in that track. After a track has been recorded, dial 21 is rotated so as to position the recess 23 opposite the next indica~ion on the index scale 28. Hence, the dial and the index scale cooperate to display an indication of the number of tracks which have been recorded on the magnetic disk 3. Such indications may be analo~us to the indications normally provided on phctographic film which apprises the user of either the number of pictures which he has taken or the number of pictures which remain available on that filmO
Stated otherwise7~ the recess 23 cooperates with the index scale 28 to apprise the user of the remaining capacity of ma~netic disk 3 which is available for further recording.
While the present invention has been particularly shown and described with reference to a prefereed embodiment, it should be readily appreciated by those of ordinary skilled in the art that various changes and modifications in form and details may be made without departing from the spirit and scope of the invention. Some of these modifications have been descrived above and others will be obvious to the reader. It is intented that the appended claims be interpreted as including the foregoing as well as other changes and modifications.

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Claims (14)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A magnetic disc cartridge of the type having a jacket for containing a rotatable magnetic disc therein, said disc having a hub member for receiving a drive member to rotate said disc to record information in circular tracks on said disc and comprising an opening in said jacket through which said hub member is accessed; and externally accessible indicator means provided on said jacket for indicating the number of tracks in which information has been recorded by incremental rotation.

2. The magnetic disc cartridge of claim 1 wherein said indicator means comprises a circular dial; a pointer associated with said dial; and an index scale for providing track member indications; said dial and said index scale being relatively movable with respect to each other.

3. The magnetic disc cartridge of claim 2 wherein said dial is rotatably mounted in said jacket, and said jacket is provided with a further opening for receiving means to rotate said dial.

4. The magnetic disc cartridge of claim 3 wherein said dial is provided with a recess for receiving a projection on said means to rotate said dial, such that the rotation of said projection rotatably drives said dial.

5. The magnetic disc cartridge of claim 4 wherein said recess is said pointer.

6. The magnetic disc cartridge of claim 3 wherein said indicator means further comprises releasable locking means provided in said jacket for releasably locking said dial at discrete rotary positions.

7. The magnetic disc cartridge of claim 6 wherein said dial includes a rotatable gear member having peripheral teeth; and said releasable locking means comprises resilient pawl means for insertion between adjacent teeth to lock said rotatable gear member and said dial at the then-present position thereof.

8. The magnetic disc cartridge of claim 7 wherein said jacket includes spaced apart top and bottom walls defining a space for said magnetic disc; and further including means for mounting said resilient pawl means on the inner surface of one of said walls.

9. The magnetic disc cartridge of claim 8 wherein said resilient pawl means comprises a resilient arm having a nose portion for insertion between adjacent teeth of said rotatable gear member.

10. The magnetic disc cartridge of claim 9 wherein said means for mounting said resilient pawl means comprises a mounting block mounted on said inner surface of said one wall, said mounting block and said resilient arm being of unitary construction with said resilient arm depending from said mounting block.

11. The magnetic disc cartridge of claim 8 wherein said dial is formed on said rotatable gear member and is of unitary construction therewith.

12. The magnetic disc cartridge of claim 11 wherein said clear member is symmetrically disposed with respect to said dial, such that substantially equal portions of said dial extend above and below said gear member.

13. The magnetic disc cartridge of claim 7 wherein adjacent peripheral teeth of said clear member are angularly spaced apart by a distance corresponding to the separation between adjacent tracks on said disc.

14. The magnetic disc cartridge of claim 13 wherein said track member indications are angularly spaced apart from each other by an integral multiple of the angular separation between adjacent peripheral teeth of said gear member.