US2457699A

US2457699A - Magnetic recorder with friction drive device incorporatied within the magazine

Info

Publication number: US2457699A
Application number: US585545A
Authority: US
Inventors: Richard A Marsen
Original assignee: Lear Inc
Current assignee: Lear Inc
Priority date: 1945-03-29
Filing date: 1945-03-29
Publication date: 1948-12-28
Anticipated expiration: 1965-12-28

Description

Dec. 28, 1948. R. A. MARSEN 2,457,699

' MAGNETIC RECORDER WITH FRICTION DRIVE DEVICE INCORYORATED WITHIN THE MAGAZINE Filed larch 29, 1945 2 Sheets-Sheet 1 1948- R. A. MARSEN MAGNETIC RECORDER WITH FRICTION DRIVE DEVICE INCORPORATED WITHIN THE MAGAZINE Filed March 29. 1945 2 Sheets-Sheet 2 MVENYUR Patented Dec. 28, 1948 MAGNETIC RECORDER WITH FRICTION DRIVE DEVICE INCORPORATED WITH- IN THE MAGAZINE Richard A. Marsen, New York, N. Y., assignor, by mesne assignments, to Lear, Incorporated, Grand Rapids, Mich., a corporation of Illinois Application March 29, 1945, Serial No. 585,545

Claims.

This invention relates to magnetic recording systems incorporating a novel drive arrangement for reeling the wire or tape at a uniform speed throughout the recording interval.

To secure the best results in magnetic recording systems of the type employing a linear magnetic recording medium such as a wire or tape, it is essential that the recording medium be moved at a substantially uniform rate past the translating head. Generally, the recording medium is stored on a pair of reels, and wound up on one reel as it is unwound from the other. Means are usually provided for driving the take on reel at a uniform rate throughout the recording antennae. However, since the diameter of the wire or tape coiled on the reel increases during the recording interval, its linear speed past the translating head likewise increases, resulting in non-uniformity of recording quality along the length of the medium. For example in an hour of recording, such speed difference may be more than fifty percent. Since the frequency characteristic of recording on a magnetic medium is generally proportional to its speed of movement,

the advantages of constancy of such speed are important.

Various relatively complicated means have been devised to overcome this diillculty and provide uniform speed of the recording medium past the translating head. Generally, these have embodied one or more additional driving means engaging the recording medium between the reels or spools, and have therefore added to the expense, complexity, number of component parts and weight of the driving mechanism. This has been particularly so in magnetic recording systems of the type in which the magnetic wire or tape is stored in a magazine which is detachably cooperative with a translating unit containing driving mechanism for the recording medium, and electrical components for recording or reproducing.

It is among the objects of this invention to provide magnetic recording systems including simple novel drivin mechanism for moving the recording medium at a continuously uniform speed relative to the magnetic translating head; to provide a novel magazine type magnetic recording system including a simple, inexpensive magazine containing reels for interchangeably receiving the magnetic recording medium for linear movement with respect to a translating head; to provide such a magazine detachably cooperative with a translating unit including friction driving means engaging the recording medium coiled on reels and a translating head cooperative with the recording medium; to provide such a magnetic recording system including simple latching means for maintaining the magazine in properly aligned relation with the translating unit; to provide such a system including means automatically operable to take up slack in the magnetic recording medium as the magazine is engaged with the translating unit; and generally to provide a simple, inexpensive, lightweight and efiicient magnetic recording system.

These and other objects, advantages and novel features of the invention will be apparent from the following description and the accompanying drawings. In the drawings:

Fig. 1 is a perspective view of a translating unit and a magazine engaged therewith, according to the present invention.

Fig. 2 is a longitudinal sectional view through cooperating portions of the magazine and unit of Fig. 1.

Fig. 3 is a view on the line 3-3 of Fig. 2, illustrating the translating head and its spooling mechanism.

Fig. 4 is a transverse view, partly in section, of the magazine and unit showing latching means for the magazine.

Fig. 5 is a perspective view of the magazine, on a reduced scale, showing one element of the latching means.

Fig. 6 is a view similar to Fig. 3 illustrating a slightly modified form of the driving mechanism.

Fig. 7 is a plan view of the driving mechanism in the translating unit.

Fig. 8 is an end elevation view of the mechanism shown in Fig. 7.

Fig. 9 is an end view of a modified form of translating head for use with the invention.

Generally speaking, the present invention comprises a magnetic recorder containing a pair of spaced reels interchangeably receiving a linear magnetic recording medium. In the illustrated embodiment of the invention the reels and recording medium are mounted in a detachable magazine engageable' with the recorder unit. However, the invention drive may be used in a non-magazine arrangement. The magazine is detachably cooperative with a translating unit that contains driving mechanism for the recording medium, a translating head cooperable with the recording medium, and electronic components for recording and reproducing intelligence on or from the recording medium. Simple latching means are provided which are automatically r operative upon engagement of the magazine with the translating unit to latch the same in properly aligned relation with the translating unit.

Spooling mechanism is provided in association -with the translating head for level winding of provision of driving means which frictionally engage the magnetic recording medium, such as wire or tape, coiled on the reels in the magazine. The driving mechanism directly engages the recording medium coiled on the reels, and is operated at a uniform speed by suitable drive means. Compensating change occurs in the driving engagement whereby uniform traversing speed of the recording medium with respect to the translating head throughout its length is accomplished.

Referring to Fig. 1 of the drawings, illustrated embodiment of the magnetic recording system of the invention includes a magazine l8, containing the magnetic recording medium and a pair of reels interchangeably receiving the medium and which is detachably cooperative with a translating unit l5. Unit contains driving mechanism and a magnetic translating head cooperable with the recording medium in magazine Ill.

Unit |'5 also includes suitable electric and electronic circuit components for recording or reproducing as will be understood by those skilled in the art. A microphone 28, provided with a switch II, is connectable to unit l5 through a plug l2 cooperable with the jack |3.- A loud speaker, or other sound reproducing means, is mounted in unit |5 behind a grill l4. A suitable on-oif switch I6 is provided, as well as control knobs generally indicated at H, and indicating lights l8 and 2|. A further control knob 22 is provided for controlling the direction and speed of movement of the recording medium in magazine III with respect to the translating head in unit l5.

Referring more particularly to Fig. 2, magazine l0 comprises a casing 26 having an elongated aperture 21 in its bottom wall. A pair of

reels

28 and 3| are rotatably mounted in magazine I0 on longitudinally spaced shafts 32, 33 extending transversely of the magazine. The magnetic recording medium 35, which is suitable magnetizable wire, is disposed on

reels

28 and 3| and is wound on one reel as it is unwound from the other reel. In passing between the reels, wire 35 passes under guiding rollers 38, 36 freely rotatable on

shafts

31, 31 extending transversely of magazine I0.

As shown more particularly in Figs. 4 and 5, suitable means are provided for detachably holding magazine III in aligned relation with translating unit l5. Such means may comprise latch bars 4|, 4| pivotally mounted on

brackets

42, 42 on the upper wall 43 of unit l5. Wall 43 is provided with an aperture 44 having substantially the same dimensions and shape as the bottom wall of magazine Ill whereby the magazine may be inserted through the aperture. Springs 45, 45 normally maintain the outer ends of latch bars 4| in engagement with

brackets

46, 46 se- The translating head is especured to wall 43. The inner ends of latch bars 4| are beveled as at 41 for cooperation with similarly

bevelled recesses

48, 48 pressed into front and rear walls 50, 5| of magazine l0. Magazine I8 is preferably formed of thin sheet material so that walls 50, 5| may be sprung inwardly a small amount.

In operation, as magazine I0 is placed through aperture 44, the inner ends of latch bars 4| move downwardly until they engage with bevelled recesses 48. It will be noted that recesses 48 extend longitudinally a substantial distance and bars 4| have a length of the same order as that of the bevelled recesses. Therefore, the latch bars 4|, in cooperation with bevelled recesses 48, maintain magazine III in the proper position with respect to translating unit l5. To release magazine Ill, it is gripped by hand and side walls 50, 5| are pressed inwardly towards each other, thereby disengaging bevelled recesses 48 from latch bar 4|. The magazine may then be readily withdrawn from the unit.

An important feature of the present invention is the novel driving arrangement for the recording medium. The invention driving arrangement traverses wire or tape 35 at a substantially uniform speed with respect to a suitable slotted magnetic recording head mounted in unit I5. An adjustable speed drive for this arrangement is shown in Figs. 7 and 8. However, such drive may take one of other well known forms. The illustrated drive includes a motor 55 having an armature shaft 56 on the end of which is mounted a friction disk 51. The drive shaft 58 is provided with a key-way 6| that extends traversely of recorder unit l5 and has mounted thereon a driven roller 62 having a rim of rubber or other suitable friction material engaging disk 51. The hub 63 of roller 62 is provided with a key 64 engaged in key-way 6|, so that drive shaft 58 is rotated with roller 62, and the position of roller is adjustable longitudinally of the shaft for changing the speed ratio of drive of shaft 58.

Roller 62 is moved longitudinally of drive shaft 58 by a, U-shaped bracket 65 having arms 86, 61 provided with apertures engaging shaft 58 and a threaded aperture '88 in its base engaged by a threaded member Ill. Threaded member 10 is adapted for rotation by knob 22 on the forward face of translating unit l5. By suitable rotation of knob 22, roller 62 may be adjusted diametrically of disk 51 to vary the speed of rotation of the roller 62 or to reverse its direction of rotation in a manner well known to those skilled in the art. Alternatively, a shifting lever or slide may be used to set bracket 65 and roller 62 for speed control of drive shaft 58. Shaft 58, which is rotated by roller 62 operates the novel driving arrangement for

reels

28, 3| and recording wire 35.

Referring more particularly to Fig. 2, the driving arrangement includes a. pair of friction rollers I5, 88 provided with rims 16 of rubber or other suitable friction material. In a manner to be described, rollers 15, 80 are urged into continuous frictional engagement with the wire 35 coiled on

reels

28 and 3|. Friction rollers I5,

I 88 are driven at a uniform angular velocity, and

lower ends of arm 11, 18, respectively, and pins 85, 88, normally urge arms I1, 18 in a direction to move rollers I5, 80 upwardly toward aperture 44. Rollers I5, 80 are-mounted on shafts 81, 88 in the upper end of arms 11, I8 and are preferably secured thereto by suitable means such as welding. brazing and so forth. Also secured to shafts 81, 88 are

pulleys

90, 9| provided with bevelled peripheries for engagement by flexiblebelts 02, 93 which are engaged with pulleys 94, 95 (Fig. 7) pinned to rotate with drive shaft 58. By the described arrangement, rotation of drive shaft 58 is smoothly imparted to

pulleys

94, 95 and through

belts

92, 93 to

pulleys

90, 9|. Rollers I5, 80 are therefore driven at equal uniform angular velocities to draw the wire 35 at a constant rate through recording head 90, and with no drive ripples that gearing would impart.

It will be noted that roller shafts 81 and 88 are offset outwardly with respect to vertical lines passing through reel shafts 32, 33, when the magazine I is in position. Therefore, when magazine I0 is inserted into aperture 44 and rollers I5, 80 engage the wire wound on reels 28. 3I, drive rollers I5, 80 are moved away from each other to exert a tensioning effect on record ing medium 35 to take up any slack therein and maintain the portion of the medium between the reels taut. Suitable means such as stop pins 91, 98 are provided to engage arms 11, I8, respectively, to limit movement of rollers I5, 80 toward each other when magazine In is disengaged from translating unit I5.

Translating unit I includes magnetic translating head 90, and spooling mechanism for reciprocating head 60 transversely relative to magazine I0 to wind wire 35 in uniform layers on to and off of

reels

28, 3|- as shown in Figs. 2 and 3. A pinion I00 is secured for rotation with shaft 58 and, through'intermediate gearing IOI, I02, rotates a gear I03 secured to a. spooling shaft I04 having oppositely extending helical rooves I05, I00 in its outer surface. Helical grooves I05, I06 are engaged by a suitable pin I09 in a block I01 mounted on shaft I04 and held against rotation with respect thereto by a transversely extending rod II9 (Fig. 2). When shaft I04 is rotated during movement of recording medium 35, block I01 will be reciprocated longitudinally of the shaft by alternate engagement of pin I09 with the helical grooves i05, I06.

Block I 0! serves as a support for translating head 60, which is secured thereto by suitable brackets I08, I 08 preferably of non-magnetic material such as composition, brass, aluminum, etc. Magnetic recording head 50 comprises a magnetic core IIO and a magnetizing coil III. The upper arms of core III), which is preferably constructed of suitable laminated ferro-magnetic material are separated a minute distance to provide a gap 2' in the magnetic circuit across which the wire 35 is passed and coacts therewith for recording or playback in a manher well understood by those skilled in the art.

Referring to Fig. 3, the upper surface of the inwardly extending arms of core H0 is provided with a narrow transverse slot or groove II2 that receives wire 35. Upwardly from groove H2, the arms are bevelled outwardly as indicated at H3 and a pair of trapezoidal members H4, H5

of suitable non-magnetic material such as copper brass, aluminum, plastic, etc., are secured to core I I 0. As will be noted from Fig. 3, a relatively wide angle V-groove is thereby provided leading inwardly to narrow groove H2. The described arrangement insures proper engagement of wire 35 with head as magazine I0 is placed into translating unit I5. The width of the upper end of the V-groove head 60 is substantially equal to the interior width of

reels

28, 3|, so as to engage wire 35 irrespective of the relative lateral position of the wire on the reels. Upon such engagement, the wire 35 will be guided into groove II2 as the magazine is pressed into recording position on unit I5. This described arrangement facilitates proper coaction between magazine I0 and translating unit I5 when the magazine is engaged with the unit.

Fig. 6' illustrates an alternative arrangement for mounting driving rollers 15, 90. As shown, angular arms I1, 18 are replaced by straight arms 11, I8 pivoted on shaft 58. Springs 83', 84 connected to the arms and to a pin H6 urge the arms and rollers I5, for continuous driving engagement with the wire and

reels

28, 3|. This arrangement otherwise operates in the same manner as does that illustrated in Fig. 2. The position of arms 11', I8 are shown in their uppermost position against stop pins 91, 98. As the

magazine containing reels

28, 3| is pressed into position in unit I5 drive rollers I5, 80, in either embodiment, are automatically adjusted to maintain driving and frictional engagement with the peripheral surfaces of the wire 35 on the reels 28, 3I.

Fig. 9 shows a modified form of recording head 60 particularly adaptable for use with magnetizable tape as the recording medium. As shown, the narrow groove II2 of head 50 is replaced by a relatively wide slot III across which the tape is guided in a corresponding manner as the wire 35 is guided through head 90. In some applications utilizing a magnetic tape, there is no need for transverse spooling for layer winding as provided for the wire.

The described magnetic recording system provides a magazine construction which is greatly simplified over those hitherto used in that it need contain only the reels and the wire or tape wound thereon. The driving mechanism for the recording medium, the translating head, the spooling mechanism therefor, and the electronic components of the system are all contained within unit I5. Consequently, the cost of magazine I0, as well as its weight and size, may be greatly reduced.

The driving mechanism provides a simple means for traversing the recording medium at a constantly uniform speed with respect to the recording head. This insures the maximum and uniform recording and playback quality and response. The drive ratio between the drive rollers and the wire reels are automatically adjusted to provide the constant uniform linear speed of the magnetic wire or tape. Furthermore, by a simple arrangement, the driving mechanism is designed to automatically tension the recording medium and take up any slack therein upon engagement of the magazine with the translating unit. The recording wire, also, is automatically engaged by the translating head, which in turn is traversed for layer winding the wire. Simple and easily disengageable latching means are provided for maintaining the magazine in proper relation with the translating unit when engaged therewith.

While specific embodiments of the invention have been described in detail to illustrate the application of the principles thereof, it will be understood that the invention may be otherwise 7 embodied without departing from such principles.

What is claimed is:

1. A magnetic sound translatingunit adapted to cooperatively receive a magazine containing a linear magnetic recording medium coiled on spaced reels, said unit comprising a casing having an aperture in a wall thereof adapted to receive the magazine; frictional drive means for engaging the periphery of the medium as coiled on the reels in said casing adjacent the aperture; and driving mechanism in said casing for driving said frictional drive means at a uniform speed when the magazine is engaged in the aperture to motivate the medium at a constantly uniform rate irrespective of the diameter of the coils of medium on the reels.

2. A magnetic sound translatingunit adapted to cooperatively receive a magazine containing a linear magnetic recording medium coiled on spaced reels, said unit comprising a casing having an aperture in a wall thereof adapted to receive the magazine; a pair of friction rollers mounted in spaced relation in said casing adjacent the aperture; and driving mechanism in said casing for rotating said rollers at a uniform angular velocity; said rollers frictionally engaging the recording medium coiled on the reels, when the magazine is engaged in the aperture, to draw the medium longitudinally of the magazine at a uniform speed irrespective of the diameter of the coil of recording medium on either reel.

3. A magnetic sound translating unit adapted to cooperatively receive a magazine containing a linear magnetic recording medium coiled, on spaced reels, said unit comprising a casing having an aperture in a wall thereof adapted to receive the-magazine; frictional drive means for engaging the periphery of the medium as coiled on the reels in said casing adjacent the aperture; driving mechanism in said casing for driving said frictional drive means at a uniform speed when the magazine is engaged in the aperture to motivate the medium at a constantly uniform rate irrespective of the diameter of the coils of medium on the reels; and a magnetic translating head engageable with the recording medium as it is motivated.

4. A magnetic sound translating unit adapted tive of the diameter of the coils of medium on the reels; a magnetic translating head engageable with the recording medium as it is motivated; and spooling means operating said head to layer wind the medium as it is traversed across said head and between said reels.

5. A magnetic recording system comprising, in

combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a linear magnetic recording medium and a pair of spaced rotatable reels for interchangeably receiving said medium; said sound translating unit containing frictional drive means for engaging the periphery of the medium as coiled on the reels, a magnetic translating head arranged to receive said recording medium when said magazine is engaged with said unit. and mechanism for driving said frictional drive means at a uniform speed to motivate the medium at a constantly uniform rate irrespective of the diameter of the coils of medium on the reels.

6. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageable mounted thereon, said magazine containing a linear magnetic recording medium and a pair of spaced rotatable reels for interchangeably receiving said medium; said sound translating unit containing frictional drive means for engaging the periphery of the medium as coiled on the reels, resilient means for maintaining uniform engagement of said frictional drive means against the medium on the reels, a magnetic translating head arranged to receive said recording medium when said magazine is engaged with said unit, and mechanism for driving said frictional drive means at a uniform speed to motivate the medium at a constantly uniform rate irrespective of the diameter of the coils of medium on the reels.

7. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a linear magnetic recording medium and a'pair of spaced rotatable reels for interchangeably receiving said medium; said sound translating unit containing a pair of spaced rotatable driving elements, mechanism for rotating said elements at a uniform angular velocity, and a magnetic translating head arranged to receive said recording medium when said magazine is engaged with said unit; said elements frictionally engaging the recording medium coiled on said reels, when said magazine is engaged with said unit, to draw the medium longitudinally at a uniform speed irrespective of the diameter of the coil of recording medium on either of said reels.

8. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a linear magnetic recording medium and a pair of spaced rotatable reels for interchangeably receiving said medium; said sound translating unit containing a pair of spaced rotatable driving elements, mechanism for rotating said'eiements at a uniform angular velocity and resilient means urging said elements into frictional peripheral engagement with the recording medium coiled on said reels, when said magazine is engaged with said unit, to draw the medium longitudinally at a uniform speed irrespective of the diameter of the coil of recording medium on either of said reels.

9. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a linear magnetic recording medium and a pair of spaced rotatable reels for interchangeably receiving said medium; said sound translating unit containing a pair of spaced rotatable driving elements, mechanism for rotating said elements at a uniform angular velocity and resilient means urging said elements into frictional peripheral engagement with the record ing medium-coiled on said reels, when said magazine is engaged with said unit, to draw the medium longitudinally at a uniform speed irrespective of the diameter of the coil'of recording medium on either of said reels; said driving elements being movable away from each other upon engagement with the coiled recording medium to take up slack in said medium between said reels.

10. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a magnetic recording wire and a pair of spaced rotatable reels for interchangeably receiving the wire; said sound translating unit-containing a pair of spaced rotatable driving elements, driving mechanism for rotating said elements at a uniform angular velocity, and a magnetic translating head arranged to receive said recording wire when said magazine is engaged with said unit; said elements frictionally engaging the wire coiled on said reels, when said magazine is engaged with said unit, to draw the wire longitudinally at a uniform speed irrespective of the diameter of the coil of recording wire on either of said reels; and spooling mechanism operable by said driving mechanism to reciprocate said head laterally relative to the wire to layer wind the later onto and off said reels.

11. A magnetic recording system comprising,

in combination, a sound translating unit and amagazine disengageably mounted thereon, said magazine containing a magnetic recording wire and a pair of spaced rotatable reels for interchangeably receiving the wire; said sound translating unit containing a pair of spaced rotatable driving elements, driving mechanism for rotating said elements at a uniform angular velocity, a magnetic .translating head arranged to receive said recording wire when said magazine is engaged with said unit, resilient means urging said elements into frictional engagement with the wire coiled on said reels, when said magazine is engaged with said unit, to draw the wire at a uniform speed irrespective of the diameter of the coil of wire on either of said reels, and spooling mechanism operable by said driving mechanism to reciprocate said head laterally relative to the wire to layer wind the latter onto and oi! said reels.

12. A magazine adapted to be engageable with a magnetic soundtranslating unit having friction driving means operable at a substantially v uniform speed, said magazine comprising, in combination, a casing; and a pair of spaced rotatable reels for interchangeably receiving said medium; said casing being apertured adjacent said reels whereby the driving means will engage the recording medium coiled on said reels. when said magazine is engaged with the unit, to draw the medium longitudinally of said casing at a uniform speed irrespective of the diameter of the coil of recording medium on either of said reels.

13. A magazine adapted to be engageable with a ma zneticsound translating unit having friction driving means operable at a substantially uniform speed and a magnetic translating head, said magazine comprising, in combination, a casing: a pair of spaced rotatable reels for interchangeably receiving said medium; one wall of said casing being apertured adjacent said reels whereby the driving means will engage the re- 10 cordingmedium coiled on said reels, when said magazine is engaged with the unit, to draw the medium longitudinally oi. said casing at a uniform speed irrespective of the diameter of the coil of recording medium on either of said reels; and

guiding means adjacent said wall for maintain ing said recording medium aligned for cooperation with the translating head.

14. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a linear magnetic recording medium and spaced rotatable reels for drawing said medium in either direction longitudinally of said magazine; said sound translating unit comprising a casing having an aperture in a wall thereof.

for receiving said magazine, and driving mechanism aligned with the aperture; said driving mechanism entering into operative association with the recording medium coiled on said reels upon insertion of said magazine into the aperture in said casing; and releasable latching means automatically operative, upon insertion of said magazine into the aperture in said casing, to retain said magazine in cooperative engagement with said unit.v

15. A magnetic recording system comprising, in combination, a sound translating unit and a magazine disengageably mounted thereon, said magazine containing a linear magnetic recording medium, and spaced rotatable reels for drawing said medium in either direction longitudinally of said magazine; said sound translating unit comprising a casing having an aperture in a wall thereof for receiving said magazine, and driving mechanism aligned with the aperture; said driving mechanism entering into operative association with the recording medi"m coiled on said reels upon insertion of said magazine into the aperture in said casing; and releasable latching means automatically operative, upon insertion of said magazine into the aperture in said casing, to retain said magazine in cooperative engagement with said unit; the side walls of said magazine having recesses for engageably cooperating with said latching means. I

RICHARD A. MARSEN.

REFERENCES CITED UNITED s'ra'ms ra'ran'rs Number I Name Date 1 2,089,287 Molloy Aug.10, 193': 2,361,753 7 Eilenberger Oct. 31, 1944 2,369,017 Camras Feb. 6. 1945 2,372,810 Camras Apr. 3, 1944 {roman ra'mn'rs Number Country Date 608,202 France Nov. 1'1, 1930 633,160

' Germany July 21, 1936