US2764241A - Wiring unit for punched record reproducing machine - Google Patents

Description

0. E. KASE Sept. 25, 1956 WIRING UNIT FOR PUNCHED RECORD REPRODUCING MACHINE 5 Sheets-Sheet 1.

Filed May 22, 1952 F|G. l

INVENTOR.

OTTO E.. KASE A U RN E g 0. E. KASE Sept. 25, 1956 WIRING UNIT FOR PUNCHED RECORD REPRODUCING MACHINE Filed May 22, 1952 5 Sheets-Sheet 2 i a J w. \\L a E v n .V m x 2 i H g M v v 1 1 1 1-1. V T 2 F mw in 2f; 5 S. O l WM n H/ V. B u m 2 8 4 w E; .1 fi m S 8 m U E Fl 3 2 L h I a. 7 2 M1 1. z n &@ 8 &@ 3 g &@ &% m 0 O 2 m A o F 000 7 w @w w n .LL DI E E 0. E. KASE Sept. 25, 1956 WIRING UNIT FOR PUNCHED RECORD REPRODUCING MACHINE 5 Sheets-Sheet 3 Filed May 22, 1952 OTTO E. KASE INVENTOR.

Om NN B o O I ozmzwm E29 UOIW O2 200 m .6. m m h MOE L. 1m 22/ ATTORNEYS 0. E. KASE Sept. 25, 1956 WIRING UNIT FOR PUNCHED RECORD REPRODUCING MACHINE Filed May 22, 1952 5 Sheets-Sheet 4 FIG.8

INVEN TOR.

' OTTO E. KASE J11 ATTORNEY 0. E. KASE Sept. 25, 1956 WIRING UNIT FOR PUNCHEJD RECORD REPRODUCING MACHINE 5 Sheets-Sheet 5 Filed May 22, 1952 FIG.6

FIG]

INVENTOR.

- OTTO E KAS BY ATTORNEYS United States PatentO WIRING UNIT FOR PUNCHED RECORD REPRODUCING MACHINE Otto E. Kase, Stamford, Conn., assignor, by mesne assignments, to Sperry Rand Corporation, New York, N. Y., a corporation of Delaware Application May 22, 1952, Serial No. 289,300

Claims. (Cl. 164--114)- This invention relates to new and useful improvements in wiring units and has particular reference to a novel wiring unit used in a Multi-ControlReproducer for my co-pending application Serial No. 292,324, filed June 7, 1952, and entitled Card Position Selecting Means.

In the operation of this novel device the general operation requires that the cards to be fed into the interpreter be provided with suitable control holes which, through suitable mechanism on the interpreter, control" the operation of the card stops so that the printing takes place on the proper line. For instance, if a card is fedlinto the interpreter with no control hole in it, the printing" takes place on the first printing line; if it has one control hole in it, the printing takes place on the second printing line; if it has two control holes in it, the printin'g 'takes place on the third printing line and so on until. if [it'has twelve control holes in it (then the printing takes place On the thirteenth printing line. The mechanism-is arranged to print thirteen lines on a card. It may be provided'with means whereby the card thus fully printed or posted'may be segregated from the remainder of the cards asthey leave the machine.

It is well known, of course, that in the postinginterpreter a series of cards may be sensed and then advanced to the printing position whereupon the material sensed from a card may be printed on the same card. With the automatic line finder mechanism the line on which the printing takes place is automatically determined. In other operations a series of interfiled lead and trailercards are fed into the interpreter with the lead card introduced first to be sensed to set up in the printing mechanism information found'thereon. The trailer cards follow in order and have been previously interfiled so that they are active or match the lead card with which they'are related in the pile of cards thus interfiled.

The punching on the trailer cards of the card-stopcontrol holes for the line finding operation in a posting interpreter as above mentioned may be performed .automatically and completely through the useof an automatic line finding punching wiring unit. This uni-t maybe used with a regular multi-control reproducer or W-ithone provided with collating or interfiling -mechanism. This wiring unit is designed primarily for use withan interfiling multi-control reproducer so that the automatic punching Fatented Sept. 25, 1%56 of the card-stop-control holes may occur simultaneously with the interfiling of master or lead and detail or trailer cards for an interpreter posting operation.

The object of this invention is to provide a simple, efiicient, modified wiring unit to be used with a multicontrol reproducer, whether of the regular, collating, or interfiling type, so that while the reproducer may be performing its regular functions of feeding, punching, segregating, interfiling, or collating, it may at the same time automatically punch card stop control holes in the detail or trailer cards. Yet another object is to provide a simple, efiicient wiring unit related to adjacent sensing and punching sections of the machine whereby detail or trailer cards may pass into the sensing section, be sensed toset up punch pins according to information in the detail card, and pass to the punching section, at which time the datasensed in the card may be punched in the same or other sections of the same card.

A. further. object is to provide a wiring unit of such construction that as it is introduced into the machine it will automatically set up a wire in the punching section of the unit so that, when punching takes place, a special starter hole is punched in all cards.

A still further object is to provide meanson the" unit so thatwhen a fully posted detail or trailer card happens to be fed into the machine, the last control hole therein will be sensed to set up mechanism in the machine to eject the card instead ofinterfiling it.

Yet other objects have to do with' the provision of simple and eflicientmeans to utilize mechanism in the machine, whatever the type employed, to effect proper retraction of the wires which control the punching of the control holes during each cycle of the machine.

Furtherand more specific objects, features, andadvantages-willmore clearly appear from a consideration of the specification hereinafter set forth especially when taken in: connection with the accompanying drawings which illustrate a present preferred form which the invention may assume and which also form part of the specification.

In the ordinary multi-control reproducer there is a sensing wiring unit and a punch wiring unit disposed adjacent to each other. ln'developing this invention these two units have been permanently joined together as one unit. The sensing section of this unit maybe specified to contain what Wiring is necessary to establish comparison between cards fed by the upper and lower card feeding magazines for feeding, punching, segregating, and interfiling'purposes. This may include wiring to the sequence control unit if the machine is to be used as a collating reproducing'punch. The comparing and sequence control' wiring in the sensing section of this unit would be identical to and serve the same purpose as the like wiring'in the usual comparing or sequence comparing wiring unit.

The punching section of this novel wiring unit may be specified to contain punching wiring (if it is necessary) to punch information contained in the cards fed by the upper card feeding magazine into those fed by the lower card feeding. magazine. Of course, this section would also contain wiring to the sequence unit if the machine is to be used as a collating reproducing punch. The punching and sequence control wiring in the punching section of thisnovel' wiring unit would be identical to and serve the same purpose as the like wiring in the usual punching or. sequence punching wiring unit.

The novel features of this wiringv unit have to dowith the punching into the trailercards of card-stop-control holes to determine the line upon which printing may take place when the card is run through an interpreter. Although the control hole positions may be punched in any part of the card it is generally preferred to find these holes or positions in any column or combination of columns in the lower zone of the card (from column 46 to 90). In the following description and illustrations columns 88 to 90 will be used as an example in order to simplify the understanding of the application. These columns provide space for the punching of six holes in each of the two columns and a special starter hole in the third column. The starter hole does not control printing but when a card with such a hole enters the reproducer the hole will be sensed to punch the first control in that card as will be explained hereafter. However, any card column containing a card-stop control hole may not be used for interpretation during an automatic line finding operation. The specification that the control holes be in the lower zone is mainly for the reason that advantage may be gained of certain locking slide disabling controls which are not applied to the upper zone card columns.

One novel feature is the provision of linkage in the unit connected to a Bowden wire leading to the starter hole position in the punching section of the unit which will setup a punching die in the punching setup section of the reproducer to punch this starter hole upon the next punching operation of the machine. This linkage is operated at the time the unit is inserted into the machine and this setup is maintained until the unit is withdrawn from the machine, and consequently every detail or trailer card will be punched with the so-called starter hole except non-matched cards.

Another feature of the invention is the provision of novel wiring from the starter and card-stop-control positions in the sensing section of the wiring unit leading to the card stop control positions in the punching section of the wiring unit;

Assuming a l3-position printing device used with the automatic line finding interpreter, the wiring above mentioned is done on the following basis:

Sensing Section Punching Section From starter position to From #1 card stop control position to From #2 card stop control position to From #3 card stop control position to #1 card stop control position; #2 card stop control position; #3 card stop control position;

and so on.

starter and card-stop-control positions are wired from the sensing wiring section to the locking slide and then from the slide to the punching section of the wiring unit. This slide makes it possble to sense from a card fed by the lower card feeding magazine and to punch the result of that sensing into the same card when that card reaches the punching position. After the set-up is made in the punching section, the locking slide is retracted (cleared) ready to receive the sensing from the next card to enter the lower sensing section.

It is clear from the above description that other slides may be provided to handle other sets of wires running from one section to the other and that these wires may run from predetermined positions in one section to any other positions in the other section. Therefore information punched in a card fed to the machine in the lower level may be punched in that card in other positions as the occasion may demand. It is also thus useful to punch a card with a double set of control holes so that twentysix lines of printing may be made, in right and lefthand sections of the card, thirteen lines in each section. This latter possibility of course might require some alteration of the printing apparatus of the interpreter.

Still another feature of the invention relates to the #4 card stop control position;

wiring of the #12 card-stop-control position in the sensing section of the wiring unit to any desired position within a blank card column of the cards fed by the upper card feeding magazine. The card column selected for this purpose must be blank in all cards fed by the upper card feeding magazine. It is obvious that any card fed through the lower level which has twelve control holes punched in it has been fully printed on thirteen lines and should be segregated.

In the multi-control reproducer of any of the types mentioned, there is provided a mechanism for column comparing control and by setting this control for this selected blank column the thus fully posted cards will automatically be segregated from the remainder.

Another feature of the invention concerns the means for retracting the special locking slide or slides above mentioned. With a reproducer having sequence or collating provisions advantage is taken of certain rock arms associated with said mechanism which are connected to linkage associated with the slide to operate it for retraction cyclically. With a reproducer having no collating mechanism the slide connected linkage is operated from an arm associated with the eccentrically operated arm connected to the upper reciprocating sensing pin box of the machine.

Other features and advantages resident in this invention may be apparent from the following detailed description and general summation of the operation given at the end of the specification.

Other objects and structural details of the invention will be apparent from the following description when read in connection with the accompanying drawing, wherein Fig. l is a vertical front-to-rear section through a collating reproducer in which the invention is incorporated;

Fig. 2 is a plan view of the wiring unit shown in Fig. 1;

Fig. 3 is a transverse vertical section taken on the line 3-3 of Fig. 2;

Fig. 4 is a detail view of the mechanism for punching a starter hole into the card;

Fig. 5 is a partial side elevation of a retract mechanism cooperating in my invention in a non-collating reproducer when such a machine is used;

Fig. 6 is an end view of the mechanism shown in Fig. 5;

Fig. 7 is a vertical section taken on the line '7-7 of Fig. 5;

Fig. 8 is a horizontal section taken on the line $-8 of Fig. 5;

Fig. 9 is a detail view of part of the retraction linkage shown in Fig. 5, showing it in an operative position; and

Fig. 10 is a diagrammatic view showing how the connections for the control hole punching extend from positions in the sensing wiring section to the punching wiring section under setup control of the lock slide.

The invention is shown as embodied in a collating multi-control reproducer and is generally of the type shown in U. S. Patent No. 2,211,094, issued August 13, 1940, to K. J. Braun. Only such part of this machine will be described herein as appears necessary to understand the invention embodied therein. As shown particularly and generally in Fig. 1 there are the following general units involved:

1. Lower sensing pin box A.

2. Lower card receiving chamber B.

3. Connecting pin section C.

4. Lower sensing portion D of the wiring unit which has been somewhat modified to incorporate features of the invention.

5. Comparing unit (front section), E. 6. Comparing levers F. 7. Comparing unit (rear section), G. 8. Punch section H of the wiring unit. 9.' Punch set-up section I 10. Punching section I. E P s hereinafter set forth these units operate in the regular manner clearly set for in the above mentioned patent.

The sensing wiring unit D and the punching wiring unit H have been combined into-single structure and are of particular interest with respect to this invention. Certain columns of the card to be punched with control holes are pre-selected. Actually they may be any columns but for sake of simplicity and clarity it is here assumed that .the lower zones columns $8, 89 and 90 are used. As

shown in the diagram of Fig. the control holes which may be employed are punched in these columns, a starter hole in column 99 and six holes in each of columns 88 and 89. The holes in column 88 are numberedl to 6 and those in column 3% are numbered 7 to 12. The starter hole is punched in the top position in column 90 (lower zone).

The Wiring sections D and H in this invention are now connected as one unit by means of a supporting plate so that they may be inserted into the machine and Withdrawn therefrom in the usual manner but as one unit and not as separate sections as hitherto. This supporting plate 20 slides in grooves in side guide rails 21 and 22 as shown particularly in Fig. 3. The sections thus supported are latched in place by the usual finger-operated spring actuated latch plates 23 and 24 having end notches engaging studs 25 and 26 on the rails 21 and 22;

As shown in .Fig. 2 particularly there is a stud27 on top of the rail 22 midway thereof. This stud isadapted to engage one end of a bell crank lever 28 when the wiring unit is inserted into place in the machine. When the unit is fully inserted this engagementcauses the lever to be rocked clockwise (Fig. 4). The lever is mountedon top of plate 2% and the other end of it engages and moves a Bowden wire element 29 the adjacent end of which is mounted on a bracket 3%) mounted on the same plate 20. This wire 29, as shown in Figs. 1 and 10 extends directly to the punching wiring section to set up a pin in the punching set-up section I so that a hole will be punched in the card at the next punching operation. This wire as shown connects to the position in the punchingwiring section corresponding to the top or zero hole (lower zone) in column 90 of the card and is called the starter hole. It is clear that whenever the wiring unit is in the machine this particular punching set pin is down ready to punch with the starter hole any card that comes through.

Referring now to Figs. 1 and 10 particularly, several connections arev shown in Fig.1 and all of them areind cated in Fig. 10 insofar as they relate to thisinvention. It'is to beunderstood, as above set forth, that the. wiring connections in this unit except for those herein specifically mentioned'as related to the control features, are the usual wiring connections hitherto employed in multi-control reproducers either of the regular type, the interfiling, type, or'the collating type, which latter. is the type generally shown in Fig. 1.

As shown'in Figs. 1 and 2 a plate 33 connects .the wiring units D and H near their upper end. Securedto the plate 33 are a pair of slotted bars 33a in Which'are slidably mounted pins 32 having extrusions 39 thereon adapted to cooperate with the locking noses 38 of a lockslide 34. When a pin 3?. is moved from left to right by a Bowden wire the extrusion 359 cams the slide 34'toward thetop of Fig. Z'against the tension of spring-49 until the extrusion is latched behind the nose 38 thus holding the: selected pin operated.

As shown in 10 a Wire 31 extends from the zero position in column M? in the unit D and leads me set pin 32 in alock slide mechanism K supported ona plate 33. The slide plate is numbered 34 although the set pins are not shownin Fig. 1% which is mainly diagrammatic. From this set pin a wire 35 extends directly to the punchingsection and is related to the position therein to set up a;set-up pin to punch a hole in the fzero position in the 88th column of the card which corresponds to the numher-1 control hole indicated .in. therdiagram shown in Fig. 10. Following out the connections-indicated in the. diagram it will be perceived that the wiring connections from thelower portion of the unit proceed from a numbered position to the next higher position in the punching section until .the eleventh hole punches the 12th position hole in the card.-

In theunit the connection over the twelfth hole position extends 'upwardly and is numbered 36 (Fig. 1) and, when operated, is adapted to actuate an element such as 37 in the front section of the comparing unit E, which through the comparing leversF: will operate a similar elementin the rear comparing unit G associated'with any desired position within a blank card column of the cards fed by the upper card'feedingmagazine. The card column'se lected for this purpose must be blankin all cards fed by the upper card feeding magazine. By -setting in its efiective position the usual andwell known column comparingcontrol of the. reproducer for this blank column, the so-called fully posted cards will be automatically segregated from the balance. This usual segregating mechanism is of the. sort shown. and described in the above mentioned Braun patent.

Theslide 34 may be retracted by two different trainsof mechanism depending. upon What type of reproducing punch is being used.

Ifthereproducer is of theicollating type, the retraction of the lock slide 34 is effected as follows:

' The'bell crank 41 1 (Fig. 3) is pivoted on the frame of the wiring unit and is connected to a link 43 having a slot 44 in which rides a lateral pin 45 on. an arm 46 pivoted at 47 011a bracket 48 supported on the bottom of the usual collating pin box 49'. A spring 50' extends between pin 45 and a pin 51 on the lower end of link 43'. Another spring 52" extends from the endof'arm 46 to the adjacent plate 20 of the wiring. unit. The .other end of the arm 46 is adapted to be engaged by an arm 53 'fixedon a shaft 54 extending through a supporting block 55 mounted on the frame of the machine. A rear extension 56'ofthe arm 53 is. engaged by spring 57 to hold. the outer end of arm 53 upward and the other end of this spring is connected to the frame of the machine. To the other end of shaft 54 (Fig 2) is fixed'an arm 53'. These arms 53 and 53' are used in "collating operations ordinarily and are taken advantage of for this refractive operation. At an intermediate. point the arm 53' has connected thereto a link 58 the other end of which is connected to a crank arm 59 on a shaft 60 extending through the block 55and having a crank arm 6'1'011 its other end. The crank arm 61is connect-ed to a downwardly extending link 62' which is .connected to any suitable cyclically operated cam mechanism (not shown) to operate the linkage system above described and retract the lock slide 34. The details of this system form no part of this invention except insofar as it forms ameans for cyclicall'y causing the retraction of the lock slide to release any set-up pins preparatory to the sensing of a new card at the lower level for control punching.

If the multi-control reproducer is not of the collating type then the lock slide 34 is retracted by the following means;

Referring to Figs. 5, 6; 7, 8, and 9 particularly, ltlWlll be seen that a vertically extending rod '63 is eccentrically related to one of the main power shafts 64 of the machine. At its upper end it is connected to the upper pin box (not shown) for reciprocating said box to affect sensing of the lead cards running through the machine. This rod is employedto actuate the retract mechanism for lock slide 34 by means of a finger 65 secured at a mid-point thereof and extending horizontally therefrom. This finger has a lateral edge 66' (Figs. 5, 8, and 9) adapted, at thehigh position of the rod 63 to bear against the straight side of an arm 67 dependent from a collar 68 fixed on a shaft 69 rotatable in a bracket 70- mounted on across bar 70 extending across the side of the wiring unit. A stud 71 in c0llar'68 is connected by a spring 72 to a post 73 on bar 70'. This 7 spring keeps the arm 67 pressing against the finger 65. The lower portion of the arm 67 adjacent the finger 65 has a curved edge 74. As the eccentric movement of the rod .63 moves the finger 65 downwardly it travels down and inwardly following a path, as shown in dot and dash lines 'in Figs. and 9, and moves the arm 67 to the left and travels along this curved lower edge thereof. On the return stroke of rod 63 the finger 65 clears the arm 67 altogether. Should the motion of the machine, for some manual purpose be reversed, the curved surface of the arm edge 74 will permit the finger to pass upward without being blocked, since the arm 67 will not be moved to the right so far by spring 72 as to block the upward reverse movement of the finger.

The shaft 69 at its other end supports a dependent arm 75 pinned pivotally at 76 to a link 77 having a slot 78 therein in which rides a pin 79 on one end of a bell crank 80 pivoted at 81 and mounted as shown to the bar 70'. The outer end of the link 77 has a pin 82 connected by a spring 83 to pin 79. The other end of the bell crank 80 is pinned at 84 to the lower end of a link 85. This link 85 (see Figs. 5 and 7) extends upwardly and is connected to another link 86 which has a long slot 87 therein. A pin 88 on link 85 extends into slot 88. A set screw is threaded into link 85 above the pin 88 and its stem extends through the slot 87 and its head 89 locks the two links together. This construction permits the longitudinal relative adjustment of links 85 and 86 but prevents any relative angular I movement. The upper end of link 86 is pinned at 90 to the previously described bell crank 41 which contacts the lock slide 34.

General operation Assuming a series of trailer cards are passing through the lower level of the device. It is clear that if a card is sensed that has no control hole in it, it is nevertheless going to have a starter hole punched in it by reason of the mere insertion of the wiring unit into the machine as above mentioned. If it has a starter hole already punched in it this hole will be repunched but also a control hole in the number 1 position as indicated in the diagram of Fig. will.-

be punched therein. If it already has a starter and one control hole punched in it these two holes will be repunched but a number two hole will be punched and so on until twelve holes have been punched in it. When a card enters the machine with twelve control holes already punched in it, the sensing of this twelfth hole will lift the wire 36 in the sensing wiring unit over this position and cause the eject mechanism of the reproducer to act as above described to throw this fully posted card into a preselected pocket and thus remove it from those cards which are not fully punched.

All the time that this punching of control holes is proceeding, the machine may be set for ordinary operations such as card feeding, punching, segregating and interfiling operations desired through the intermediary of the other wire connections in the units which are connected in the usual manner to perform these functions.

As far as the automatic punching of card stop control positions is concerned, the setting for the card punching operation is most important. The punching of these positions is controlled to selectively punch just as though the information were being sensed from the cards fed by the upper card feeding magazine, whereas, in truth, they are being sensed from the trailer cards and punched in these same cards. This fact brings us to the obvious conclusion that this wiring unit and its operative relation to trailer cards will permit information punched on trailer cards to be punched in the same cards in any desired columns or position thereon whether the punched data being sensed relates to control holes or to regular punched data.

In most cases, though not necessarily so, the machine is set to operate with lead cards and to punch on, match or equal trailer cards. Then only the matching or active cards would be punched with a new card stop control hole. The operation for which the automatic line finding punching wiring unit is primarily designed is the interfiling of matching lead and trailer cards just prior to a posting operation in the interpreter, that is, lead cards interfiled ahead of matching trailer cards, and inactive or nonmatching trailer cards being segregated.

The punching of the starter and control holes in matched trailer cards would occur as follows: Every trailer card will be punched or repunched with the starter hole as they pass through the punching section of the machine. As this starter hole has no effect upon the automatic line finding feature of the interpreter, the cards punched with this hole only will be interpreted on the first printing line. When a trailer card punched with the starter hole only enters the sensing section of the wiring unit this position, as above described, will cause it to be subsequently punched with a control hole in the first control hole position. In natural order, cards already punched with the number 2 control hole will be sensed in the hole and set up connections to punch it with a number 3 hole and so on until the card is punched with the full complement of holes whether it be a few or many but generally not more than twelve holes since the card can only be printed in this case with thirteen lines of printing. Of course it is realized by now that all previous positions in the cards are sensed and set up in the punching section. However, this will have no new effect except merely to repunch.

It is to be borne in mind that I have set forth an example showing the use of twelve control holes with the twelfth hole connected so as to reject a card thus punched as it is sensed in the sensing section. However, there may be fewer holes used and the last one would be connected to reject the card so punched.

As previously stated, when the reproducer is of the collating type the retract mechanism for the lock slide 34 is of the form shown in Figs. 2 and 3. If the reproducer is of the regular or interfiling type then the retract mechanism of the form shown in Figs. 5 to 9 is used.

While the invention has been described and shown with respect to specific forms it may assume in practice, it is not to be limited to such details and forms since many changes and modifications may be made in the invention without departing from the spirit and scope of the invention in its broadest aspects. Therefore, it is desired to cover any and all forms and modifications of the invention which may come within the spirit and scope of any one or more of the appended claims.

What I claim as new, and desire to secure by Letters Patent, is:

1. A wiring unit for multi-control reproducers which comprises sensing and punching wiring sections with wiring connections therein, a projection on the frame of the machine adjacent the wiring unit, a pivoted member on the side of the wiring unit to engage said projection and be moved by it as the unit is inserted into the machine, a Bowden wire connected at one end to said pivoted member and at the other end to a connection in the punching section to automatically set up said connection for punching when the unit is inserted into the machine.

2. A wiring unit comprising sensing and punching sections, a projecting element on the unit adapted to be moved by means exterior to the unit, a Bowden wire connected to said element and extending to a predetermined position in the punching section to set up a connection for punching in that position.

3. A wiring unit comprising sensing and punching sections which includes means made operable by the insertion of the unit into a machine for punching cards, to punch a special hole in every card that enters the machine through said sections.

4. A wiring unit comprising sensing and punching sections which includes means involving wiring connections flowing directly from the sensing section to the punching section to sense a hole in one position in the card passing through said sections, and, as a result of said sensing, to punch a hole in another position of the same card as it is disposed in the punching section.

5. A wiring unit for multi-control reproducers which comprises sensing and punching wiring sections and associatedsensing and punching sections, fixed means on the frame of the reproducer, movable means on the wiring unit adapted to be moved by engagement with said fixed means as the wiring unit is inserted into the reproducer, and a connection from said movable means to a set pin in the punching section to set the pin as said means is moved.

References Cited in the file of this patent UNITED STATES PATENTS 2,108,681 Lasker Feb. 15, 1938

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