US2459821A - Electrical code printer - Google Patents

Description

Jan. 25, 1949. L. KOZMA ETAL 2,459,821

ELECTRICAL CODE PRINTER 6 Sheets-Sheet 1.

Filed Nov. 29, 194; i

W 'IIII IH Jan. 25, 1949. 4 L. KOZMA ETAL 2,459,821

' ELECTRICAL CODE PRIN\TER Filed Nov. 29, 1945 I e snets sheeiz INVENTORS 4140/62/45 KOZ/V/l 65096625 x i i/VS Jan. 25, 1949. KOZMA Er- 2,459,821

ELECTRICAL CODE PRINTER I Filed Nov. 29, 1945 e Sheets-Shet 4 IOZGZQ INVENTORS/ um/sms xaznm BY 660F665 X. 44W;

Jan. 25, 1949. 1.. KOZMA ETAL 2,459,821

ELECTRICAL CODE PRINTER Filed Nov. 29, 1945 6 Sheets-Sheet 6 AGENT Patented Jan. 25, 1949 ELECTRICAL CODE PRINTER Ladislas Kozma and Georges X. Lens, Antwerp, Belgium, assignors to International Standard Electric Corporation, New York, N. Y., a corporation of Delaware Application November 29, 1943, Serial No.- 51'2,l44-

12 Claims.

, 1 This invention relates to electrically actuated printers suitable for use with electrical control apparatus of the type which selectively energizes actuating elements of tho. printer, such as magnets, which control the character selecting and printing mechanism. The invention is applicable to printers provided with a type wheel on which the characters are arranged in a plurality of circumferential rows, being selected by a combination of rotary and axial movements of the type wheel.

An important purpose of the invention is to provide improved character-selecting mechanism. A feature of this mechanism is a novel arrangement for selectively rotating the type wheel. Another feature involves the use of a type wheel having at least three circumferential rows of characters, the wheel being located with an intermediate row in printing position when at rest between actuating impulses, requiring only a short axial shift of the wheel to bring either end row into position for printing. A further feature is the use of a short row of characters with an intermediate character in printing position when the type Wheel is at rest, requiring a minimum of rotary selective movement to bring any character into position. The combination of these features provides a minimum of combined selective movement of the type wheel, resultingin increased speed of operation, especially when the apparatus includes means for simultaneous rotation and axial shift of the type wheel, as disclosed herein.

Other features include an improved construction and arrangement of tape and ribbon feeding apparatus, adapted to provide not only efficient operation but also a compact and convenient construction adapted for mounting .in'a case with the printed tape in suitable position for convenient reading, and an improved construction and arrangement of actuating magnets and connecting mechanism. Other objects and ad-- vantages will appear from the following description considered in connection with, the accompanying drawings, in which Fig. 1 is a face view of the left side of a telegraph printer;

Fig. 2 is a rear view thereof partly in section taken along the line 2-2 at the left of Fig. 1;

Fig. 3 is a front view thereof partly in section taken along the line 3-3 at the right of Fig. 1; I

Fig l is a front view of ribbon feeding mechanism;

Fig. 5 is a section on line 5-5 of Fig. 4;

Fig. 6 is a schematic view of the type wheel actuating mechanism;

Fig. 7 is a face view similar to Fig. 1 showing a modified form;

Fig. 8 is a face view of said form taken from the lower side. of Fig. '7; r I

Fig. 9 is an end view taken from the left of Fig. '7;

Fig.10 is a detail on line m lo of Fig. 8 showing part of the actuating mechanism; and

Fig. 11 is a detail View showing the tape feeding roll drive. p

In accordance with a novel. feature of the pres-' ent invention, an aggregate. motion mechanism is provided for selectively rotating the type wheel,

including a number oflevers which are succes- "sively connected together in cascade by means of flexible bands or belts rather than by means of the usual connecting rods or pins andsliding links, The ends of the levers to which such .bands or belts are joined are formed as arcs of, "circles about the ,fulcra oftherespective levers and thebelts lie against these arcuate portions in such manner that rocking of a lever merely shifts the corresponding belt longitudinally but does not cause a tilt of the direction of such belt. -By such an arrangement the multiplication factors of the several levers of this system remain constant regardless of movement of the other levers. .Thus the aggregation of motion performed by this mechanism is linear at alltimes,

so that the motional output of such mechanism can readilybe arranged to correspond to a number of uniformly spaced positions of a type wheel positioning member. I r

The combination of levers with flexible bands furthermore results in unusually low friction and small inertia and renders theaction of thelinkage more perfectly reproduceable than if connecting rods and pivots or pins and slots were employed.

Referring more particularly to Figs. 1, 2 and 3 of the drawings, the principal frame-work of the machine comprisesia vertical plate P31, from the front end of which two integral ears P32 and P33 project toward the left of Fig. 3 and near the rear of which is attached 'a plate P34 which also extends toward the left parallel to said ears. A vertical plate P35 is supported from ears P32 and P33 onlthe front and from plate P34 on the rear. Within the box-like space thus formed by plate "P3l, plate P35, plate P34 and ears P32 and CM3 (Fig. l), serve to control the rotary motion of a type wheel P31; the next two 0M4 and 0M5 (Figs. 3 and 1 respectively) serve to control the axial motion of this same type wheel;

while the sixth magnet PM (Fig.2) is the printing magnet which effects the actual printing and also advances the paper tape and inked ribbon. As illustrated in Figs. land 2, the six magnets are arranged in tv/otiersof three each, the arma tures of the magnets in the lower tier being arranged beneath the same and the armatur'es of the magnet of theupper tier being above the same.

The type Wheel P3! is mounted on a squareshaft P36, the end portions of whichhowever are circular and are rotatively supported in bearings P39 and P46 fixed to arms P41, P42 ot bracket P43. The front end of shaft P38 extendsthrough bearing P39 and carries a pinion P44- which meshes with the teeth of a rack P45 slidably supported in projections P46, P41 of arm-P41 The: bracket P43 thus forms the frame-work of a selfcontained unit comprising the type wheel P31, shaft P38, pinion P44 andlrack P45. This bracket P43 is supported from plate P35.

Type wheel P31 is provided with a plurality of rows of? characters, the form illustrated being provided with three rows; and when none of the selecting magnets is energized the wheel is located with a character approximately at the center of the central: row in printing; position. Mechanism is. provided for selectingother characters by rotatingv the. type wheel in either direction, and by shifting the wheel axially, as already indicated;

For rotatingthe type wheel P31 in either direction from its normal or home position, the rack- P4'5-must be pulled up or down. The motion of this rack is controlled on the one-hand by a spring P48 constantly tending to pullit upward, and on the other hand by an aggregate motion linkage which sometimes pulls it down below its normal position and sometimes lets it rise above its normal position.

As indicated generally in Fig; 6' and as also clearly shown in Fig. 1, the aggregate motion linkage comprises an initial flexible band P52, a first lever P49, whose right. end is connected to such initial band, a second band P53 connectedto the left end of such first lever P49, a second lever P56 whose left end is connected to such second hand P53, a third band P54 connected to the right end of this second lever P50. a" third lever Pi Whose right end is connected-to this third band P56 and finally a fourth band P55 connecting the left end of lever P5l tothe rack P45*which is to be moved.

The inputs of motion from magnets CMI, CM2, CM3 to this aggregate motion linkage areapplied' over three bars P56, P59 and P62. The first bar P56 is connected to the initial flexible strap P52 at the right hand end of lever P49 (Figs; 1 and 6%. The second bar P56 carries the central fulcrum ofleverP56; The third bar P62 carries the central fulcrums of both the levers P49 and P51. The end fulcrums of the levers, that is, the regions at which the flexible bands apply their forces, are provided with convex'arcuate surfaces, which extend over a sufficient arc so that the flexible bands lie against these arcuate surfaces even in the most tilted positions of the levers.- The arcuate surfaces of each lever center about the central fulcrum of the lever. The direction in which the belts extend is parallel to-the direction of movement of bars P59 and P62 which carry the central fulcra of the levers P49, P56- and P5 I.

Sliding bar P56 is normally'pulled down against back stop P5! by the tension in strap P52 and spring P51 of the linkage; but is raised by arm P58- or armature P36A whenever magnet CMI is energised. In like manner sliding bar P56 is normally pulled'downagainst back stop P66; but is" face, thus elevating bar P62.

raised by arm PM of armature P36B upon energis'ationof magnet CM2.

It will be noted that both bars P56 and P59 are arranged so that upon the cnergisation of the corresponding magnet-s CMI and CM2 these bars move. against the pull which is constantly maintained in the aggregate motion linkage by spring P46. Upon. deeenergization of such magnets (SM-i} and 0M2 the bars P56 and P59 are correspondihgly returned against their back stops P51 and Pfi'll'by'thetension of the linkage.

In accordance with. a feature of the present invention however the motion of the bar P62 upon the'ehergization of its corresponding magnet 0M3 is arranged to be in such direction as to correspond to-a yielding to the tension in the linkage; for'if all three bars were arranged to move against the pull of the linkage, every combination of energi'zation of magnets CMl CMZ and/or 0M3 1. would always give a downward motion of rack P from. its home position. But for maximum speed it is desirable that rack P45 should" move sometimesup and sometimes down from its nor mal or home position, thus reducing the maximum distance it must move. P62 is arranged to move upward upon energize..- ti'on of magnet (3M3, thus yielding to the-tension in thelinkage. The contrast between the pulling movement of bars P56 and P5 9 and the yielding movement of bar P62 is best seen from Fig. 6'.

In accordance witha further feature of the present invention, means is provided for positively locking bar P62 against upward movement in the non-energized condition of magnet CM-3, while yet permitting it to move upward upon energization of this magnet. Such meansis constituted by the roller P66 mounted on one end of bar P62 and the cam P63 mounted on a horizontal slidable'bar P64. In the normal non-energized condition of magnet 0M3 the bar P64 is heldagainst back stop P65 by spring P66 insuch position that cam P63 prevents upward motion of roller P63 and bar P62. Thus in the normal position" a vertical force on bar P62 cannot slide bar P64 horizontally no matter how great the force exerted upon bar P62, for example" by jerks or dynamic increasesof tension in the linkage;

For sliding the bar P64 to the'left a bell crank lever P61 is provided which is engaged" by arm P68 of armature P360 so as to be rocked counterclockwise upon energization of magnet CM3'. Such counter-clockwise motion of P61 pulls bar P64 to the left by means of flexible strap. P69, allowing roller P63? to roll up the sloping cam Upon the release of magnet CM3-the bar P64 is retracted to the right by spring P66, thus pushing downbar P62 and bringing cam P63" and roller P63 into the position shown in the drawing.

Whenever the cam P63 and roller P63" are in the position shown in Figs. 1 and 6, the bar P62 I is positively held against a vertical movement and thus no oscillation of this system between the opposing tensions of springs P66 and P48 can occur. ing. means P63 and P63, which effectively prevents transmission of forces from bar P62 to bar. P64, every movement of the aggregate motion linkage would give rise to an oscillation or pendulum action, determined by the masses of the linkag and the stifinesses of the two opposing springs P66 and P48.

The central fulcrums of the selecting levers P491P56 and 'PEI- are appropriately spaced between the end fulcrums of these levers so that For this reason bar If it were not for the action of the lock the aggregate motion resulting from selective movement of these levers by various combinations of bars P56, P59 and P62 will shift rack P45 either upwardly or downwardly from normal position by successive steps which correspond to the spacing between the characters on type wheel P31. 'With levers proportioned and arranged as indicated in the drawings, the type wheel may be located in any one of two circumferential positions above and three below the character that is in printing position when the type wheel is at rest, by selectively energizing magnets CMI, CMZ and M3.

Anarrangement may be provided for throwing out any of the armatures of these magnets, similar to that described hereinafter in connection with magnets 0M4 and 0M5. This is illustrated inFig. 7 in connection with armature P360 of magnet 0M3. Arm P68 is seated in a notch P61a at an end of lever P61 and is'removable therefrom by endwise movement of the arm and armature, which are then tilted backwardly by spring P611).

Figures 7 and 8 likewise disclose the use of springs P15b'and P162) for tilting armatures P36D and P38E outwardly when arms P15 and P16 are released from their respective notches.

.In addition to the aggregate motion mechanism above described for controlling the rotary motion of the type wheel in response to energize.- tion of magnets CMI, CMZ and CM3, further means is also provided for shifting this type wheel axially one step to the left or right from normal or home position. Such axial shifting means comprise a. three-armed bell crank lever P18, P1l, P81 whose arm P1! carries a pin P14 engaging an annular groove in the forward end of the type wheel P31 and whose arm P18 is in turn actuated by apin P12 on the rear end of a rocking lever P13. The rockin lever P13 is engaged at one end by arm P15 of armature P36D, and at the other end by arm P16 of armature P36E.

The attraction of armature P36D by magnet 0M4 will rock lever P13 clockwise, turning bell crank P16 counter-clockwise and shifting type wheel P31 forward. Attraction of armature P36E by magnet 0M5 on the other hand will rock'lever P13 counter-clockwise, turning bell crank Pill clockwise, and shifting type wheel P31 toward the rear of the machine.

For returning bell crank P18 to its intermediate position when neither magnet 0M4 nor 0M5 is energized, a pair of arms P11 and P18 having parallel laterally extending jaws P18 (Fig. 3) are provided which are drawn together by spring P19 and which embrace between them a block P88, attached to the main plate P35, and also the lower arm P8! of bell crank P18--P1lP8i.

Thus, any displacement of this bell crank, either toward the rear or the front of the machine (i. e. either to the left or right from its normal position, as viewed in Fig; 1) forces the two arms P11 and P18 apart against the action of the spring P19. Thetension of this spring, therefore, tends at all times to restore the bell crank P18--P1l P8! to its normal intermediate position, whereby the'ty'pe wheel P31 is brought to the intermediate, normal or home axial position shown in Fig. 1.

'When the printer is used with certain types of actuating apparatus it is'sometimes desirable to prevent magnet CM l or 0M5 from affecting the printing. This is conveniently accomplished by locating the ends of arms P15 and P16 in lateral notches P1511 and P16a in the ends of lever P13,: said arms and their respectivearmatures being. mmble er e? t e a ms we be t d:

out of said notches, allowing the armatures to swing away from the magnets into inoperative position.

In addition to the mechanism above described,

, which all serves for positioning type wheel P31 rotatively and axially under the control of mag-- tion of magnet PM armature P361 swings down about its pivot P88, so that pin P88 is moved to the left. This movement of pin P63 swings actuating arm P84 clockwise about its pivot P88 and thus the printing lever P85, which is integral with arm P88, is swung downward toward the type wheel. Just before this lever P strikes the type wheel the armature P885 abuts against the core of magnet PM. Due to the momentum of printing lever P85 the latter swings on downward until the rub.- ber hammer P88, which is clamped into the end thereof, forces ink ribbon P98 and paper tape P9! against the type wheel P31 to eifect the printing of the selected character.

Arm P82 also is provided with'a slot P92 into which extends pin P93 of rocker arm P84. This rocker arm is pivoted at P95 and its lower end lies I in line with the end of slidable lever P86. Thus when arm P82 swings toward the left side of the machine (i. e. to the left in Fig. 2) upon the energization of printing magnet PM, the rocker arm P84 is thereby swung counter-clockwise round its pivot P85 and the lower end thereof pushes sliding bar Pile to the right, as viewed in Fig. 2, against the tension of spring P91. Such movement of bar P98 to the right carries with it a lug P88 engagin a pin P99 carried by arm P|88 of centering lever P18 i. This centering lever Pl 8 l is thus swung counter-clockwise by spring PI82.

so as to engage centering cam Pl83 for the purpose of bringing the type wheel exactly to the centre of that rotary position in which it approximately stands.

Such motion of bar P98 also retracts pawl P184 mounted on the bar, so that the pawl engages the next tooth of the ratchet wheel Pi85. Upon the de-energization of printing magnet PM and the consequent retraction of bar P88 to the left under the influence of spring P81, this pawl PIM, rotates ratchet wheel Pi85 clockwise one step,v

thus turning the knurled paper advancing wheel P186 to which wheel Pitt? is fixed, soas to move the paper P8! one step forward. A holding pawl Pl 01 prevents the ratchet wheel P585 from rotating backwards during the withdrawing movement of stepping pawl P188. 7

A rubber roller P188 is carried by arm Pl89 which is pivoted at Pl l8 and urged clockwise by spring Pill, so as to press the rubber roller P188 against the paper PSI.

carriesarm Plllli. Still further rollers Pl l3, Pl l4 guide the paper tape PM from a supply roll PI 15 at the-right side of the machine toa suitable" point from which this tape can feed toward the left of the machine under roller PI 82, between knurled wheelPlllfi and rubberroller Pl88, and

hence'outover, type wheel P31.-

This printing lever ise A paper guiding when P: is mounted on the same pivot Pl I8 which assaaai The printing magnet PM also e'fiects the advancement of the ink ribbon. At the left side of armature P351? (i. e. the right side as seen in Fig. 1) is fixed an arm P154 which upon energizationof magnet PM presses against the tcp end of a vertically slidable bar P155 of the ribbon advance assembly shown in Figs. 4 and 5, thus forcing this bar downward against the reaction of a spring P156. A pin P151 in bar P1 55 engages the slotted end of a rocker arm P158, causing the latter to rock counter-clockwise about its pivot P159. The other end of rocker arm P-ESB carries a double stepping pawl Pitt, which is capable of engaging with either ratchet wheel P191 associated with the front ribbon spool P192 or ratchet wheel P193 associated with the rear ribbon spool P186.

When in the position illustrated in Fig. 4, the double pawl P190 is pressed against ratchet wheel P19! by toggle spring Pl'QS which pulls upward on pin Pi es of double pawl P199 at suchas angle as to urge the pawl to engage the teeth of wheel P191. If the double pawl P190 is swung against ratchet wheel Pitt, due to the toggle action, spring P595 will press the pawl against such left hand ratchet wheel.

With the pawl in the position shown the counter 'clockwise rocking arm P158 retracts this pawl so that the latter fall's behind the next tooth of ratchet wheel P191 under the pressure of spring P195. Subsequently, upon the de-energizati'on of magnet PM and upon the consequent upward movement of bar P155 under the force of spring ForkPZUl is suficiently loose on pin P196 so that the holding pawl and stepping pawl can rise and fall independently of one another for clearing the peaks of the teeth and dropping into the depressions between the teeth of the ratchet wheel P191. The engagement of fork P201 with pin Pies, however, ensures that when stepping pawl PM!) is swung over to the ratchet wheel P193, the holding pawl P191 will likewise swing over to this ratchet wheel.

The change-over from the one ratchet wheel to the other ratchet wheel, or vice-versa, for the purpose of reversing the direction of advance of the ribbon is efiectedunder the control of a rocker member P202 pivotally supported on base plate P198 by pivot P203. Inaccordance with a feature of the present invention, rocker member P202 carries at its ends two plates P204, P295 loosely pivoted on P202 but restrained by pins P206, P20'1 and slots P208, P209 so as to have only a limited angle of freedom. Plate P284 carries at its upper end a pair of pins P210, P211 while plate P205 carries a similar pair of pinssP2l2, P253. Ink ribbon P90 extends from each of the reels P192 and P193 directly to the nearest pair of pins, and is of the conventional type which is provided near each of its ends with a rivet or stud (not shown) to actuate ribbon reversing mechanism. The space between each pair of pins, such as P200-P2110, is so narrow that i it will not permit the passage of such rivet or stud. The freedomof movement-of each oi -the plates P264, P2li5is sufiiciently great so'that'each such plate can accommodate itself to the changing path of the ribbon as the reels varyfromiull to empty; thus it is unnecessary to pass the ribbon over a fixed pulley between the reel P1 02 and the pins P210, P21 I.

When the ribbon P becomes almost completely unwound from the left hand real, for example, the corersponding stud on the ribbon will engage pinsP2 1 0, P211 and upon continued advance of the ribbon will finally tip rocker member P202 clockwise into reversed position, the rocker member being held yieldably'in either position by the engagement of spring nose P202-a with suitable notches in the rocker member. Point P224 is thus shifted into position to engage shoulder P225 on the pawl P190 when the latter is next shifted upwardly, swinging both pawls into engagement'with ratchet wheel P193. The pawls are similarly shifted back into engagement with ratchet wheel P191 when a ribbon studis caught by pins P212, P213, rocking the member P202 counter-clockwise and shifting point P222 into position for engagement by shoulder P223.

Provision is made also for the, use of a two color typewriter ribbon with the printer described herein. A ribbon shift mechanism comprising, a plate P238 supported so as toswing from a stud P232 fixed to plate P34, and carrying four rollers P232, F233,,P234 andP235 for guidingribbon P90,

isv shown in Figures 1, 2 and 3. The movement of plate P230 and consequently the shifting of the ribbon is therefore shown as controlled. by magnet 0M3. As previously described, energizei'ion of CME causes. the movement of slide P64 toward the rear of the machine (to the left as shown in Pig. 1). A projecting part of slide. P64 engages one arm of hell crank P126 pivoted at P121 to bracket P528, and causes the opposite. arm

of the bell crank to engage ear P125. integral with plate P235, thereby swinging plate P230 outward from the machine. Spring P55 (Fig. 2-) holds plateP-230 against the bell crank when the ribbon is shifted, and against adjustable stop screw P135 when the ribbon is in unshifted position.

The ribbon shift may be dispensed with by removing. the actuating bell crank P126 to eliminate shifting of plate P230, or by adjusting stop screw P130 so that the ribbon remains permanently in the shifted position, and/or by using a onecolor ribbon and disregarding shift opera" tions.

actuated from a particular selecting impulse will be useful, for example when a ribbon color shift mechanism may be actuated to cause printing in red for every character which is selectable with the aid of magnet CM3, while for those characters whose selection involves no energizetion of the CMS magnet the printing willgbe in black. Preferably the arrangementof the characters on the type wheel would then be such that the numerals 0-9 are selected without energizae tion of magnet 0M3, whereas signs denoting the various arithmetical operations are selected by impulse combinations which involve the energization of a magnet (2M3. Thus the numerals would be printed in black and the punctuation or operation-indicating marks in red. .Magnet 0M3 or a similar actuating means may be arranged to cause three steps of rotation of the.

type wheel. Then if energization of magnets produces the same effect as if none of these is energized, certain characters (corresponding to no rotation of the type wheel) can be selected either with or without energization of magnet CM3, making it possible to print such characters selectively in either red or black.

It will be noted that in a four impulse code arrangement no provision may be made for the usual word space operation. Since the device as disclosed is intended to record figure groups which are separated by mathematical signs, this con-- ventional function of aprinting device is not required. The respective problems may be separated otherwise, for instance b the three period groups; and on account of the novel disposition of the paths of the ribbon and tape where the tape is fed at substantially a right angle to thepath of the ribbon, eifective visible printing is achieved in a type wheel printer.

It will be noted that the characters indicated on the type wheel are not reversed, as is usual. Tape PSI overlies the type on the typewheel, as shown in Fig. l and the ribbon P90 is fed across the upper surface of the tape, so that when the print hammer strikes, the impressionof the type is received from the underside of the tape. At any time the tape may be pulled manually against the friction of pressure roller P|B8 and roller PIDB to Withdraw a length of tape from the printer. Obviously, if a so-called word space is required, this can be accomplished by the operation of magnet PM after the selection of a blank space on the typewheel, assuming that a code is used in which such a selection would be available. a

The embodiment shown in Figs. 7 to 11 employs mechanisms similar in m'any'respects to the form shown in the preceding figures, and corresponding parts are identified by the same numerals. This embodiment is particularly adapted for mounting in a cabinet with the side shown in Fig. 7 uppermost; and in order to provide apparatus that is' more suitably proportioned for this purpose and with the main operating parts and replaceable supplies in readily accessible position, the mechanism has been rearranged, and in particular provides atape feed extending lengthwise of the type wheel, with the ribbon at right angles thereto.

The aggregate motion lever system for rotating the type wheel is substantially the same,

and the actuating magnets are similarly mounted. The paper tape supply roll H is carried by a rotary one-sided spool 250 mounted on top plate supported by brackets 252 from plate P35. The tape passes over suitable guide rollers 253, between feed roller 254 and pressure roller 255 and into guideway 256 extending axially along and adjacent the type Wheel P31. Themargins of the guideway are turned over to hold the tape in place, and a suitable gap in printing position permits the printing hammer 251 to force the ribbon and tape against the type. The tape P91 projects to the left of the guideway .255, where it can be easily read, withdrawn and torn oi as desired.

The paper tape is fed by roller 254 driven by step mechanism actuated by magnet PM. The mechanism includes actuating arm 264 fixed to armature P365 and engaging the lower end of a pawl rocker arm 265 (Fig. '11) pivotedly mounted on the shaft 266 of feed roller 254. The roller is hollow to accommodate the drive mechanism, and is mounted on the upper end of the latter shaft. A pawl 261 on arm 265 engages mounted thereon and held by spring 81 against ratchet wheel 268 on shaft266, while a holding pawl 269 mounted on plate P35'likewise engages the wheel. The arm 265 is biased against the actuating arm 264 b leaf spring 218. With this arrangement the feed roller 254 will be rotated one step at each energizing of the magnet PM.

A somewhat different linkage is employed in this embodimentto shift the type wheel P31 in an axial direction. Actuating arms P15 and P16 engage the ends of a three armed lever.13 (Fig. 7), the center arm of which projects laterally and engages a link 213 connected to wheel=shift lever 1|, pivoted at its outer end on bracket 214 which is mounted on top plate P35 and carries wheel shaft P38. The lever H is pressed toward central position by the same construction as that employed in the previous embodiment, including the spring pressed opposed arms 11 and 18 corresponding to arms P11 and P18 and mounted on bracket 214.

A lower stub shaft 215 is 'journaled in bracket 26!) and carries printing hammer 251 freely the hammer propelling arm 216 fixed .to shaft 215. The end of shaft 215 is connected by rocker arm 211 (Figs. 8 and 10) to rocking plate 262 through a pin and slot connection 218, arranged so that the inward movement of armature P3615 when magnet PM is energizedrwill rock shaft 215, throwing the hammer 251 inwardly against the ribbon and tape, and against an adjustable stop 219 carried by bracket 26!].

Plate 262 is carried by pivot shaft 26] on bracket 260 and is biased counter-clockwise by spring 263. The centering lever P16! is freely mounted on shaft 26! and carries a dependingarm 21! (Fig. 8) yieldablyheld by spring 212 against pin 285 on arm 286, fixed to shaft 215.

With this arrangement the actuation of armature P36F and the rotation of shaft 215 will swing lever PIOI upwardly into engagement with centering cam Pl03; but in case of -interfere nce the spring 212 will permit leverPilll to yield without damaging the actuating mechanism.

The ribbon feed mechanism is essentially the same as that employed in the former embodiment, but is mounted across the left end of the frame as seen in Figs. 7 and 8, being shown best in Fig. 9.

In this arrangement the rocker arm Pl58 is actu ated through a link 28!] rearwardly biased by.

spring 28! and pivoted to. arm 282 on shaft 215.

The ribbon P is guided over rollers 283 on rock-Q ing plate 230 pivoted by studs 23! on ribbon,

mounting plate I98 attached to base plate P3l. A spring 284 presses the plate 239 inwardly against a projection on ribbon shift arm 126 (Fig. '1), which is pivoted at one end to bracket 214 and has a lateral extension288 engaging an arm-of bell crank P61. This construction provides a run -of inked ribbon P90 extending across the outer face of the tape PM in line with hammer 251 (Fig. 9).

The described embodiments are arranged to provide compact units taking up a minimum of space and adapted for housing in metal cabinets, with the printed tape fed out of the cabinet in;

position for convenient reading. Theembodiment disclosed in Figs. 1-6 is suitable for mounting i vertical position as shown, while the remaining embodiment is adapted for mounting in-flat posi;

tion, and may be combined with suitable keyboard mechanism to form a self-contained unit-suit able for desk use.

mg" device and means for selecting aoharacter on said device, including a plurality of levers at least one of'which-consists or an intermediate fulcrum portion and two arms'of unequallenc'that opposite sides of said intermediate fulcrum portion; means linkingtne'levers together to form an a gregate motion linkage, including flexible menibers'co'nnecting end fulcrumsof the levers, means for maintaining the flexible members under tension, a pluralityof selectively operable magnets, and a-plur'ality of lever actuating: devices each engaginga lever fulcrum, said. lever-actuating devices beirlg selectively"responsive to the opera tion' of said magnets to displace said latter fulcrums; saidend fulcrums comprising for each lever arcuate faces concentric with the intermediate fulcrum and bearing against the inner faces of the flexible members connected to saidlever.

31 A code cont'rolled-printer comprising-a printin'g deviceand means for selecting a characteron:

said device, including sit-least three-levers; means linking the levers-togetherto form an aggregate motion linkage, including connections between the ends of successive levers, a plurality of so. le'ctlvelyoperable magnets and'a lurality'of lever actuating devices each responsive to the operation of one of said magnets. one device engaging intermediate fulcrums oftwo of said leversandanother device engaging the intermediate fulcrum of a third lever.

4. A code-controlled printer comprising a print ing device, means for feeding an inked ribbon through a printing station, character-selecting:

means including a plurality of selectinginagnets andanaggregate linkage connected to said print lngdevice to'shift the same'and operated by'one or any number of said selecting magnets, and means operated by one of said magnets for shifting the ribbon laterally at theprinting station.

5. A code-controlled printer comprising sprinting device and means for selecting-a character on said device, including a plurality 'oi levers, means linking'the levers together to form an aggregate motion linkage, a plurality of selectively-operable magnets; and a plurality lever-actuating d'e-i vices each responsive to the operation of one of said magnets for displacing'a fulcrum of a lever,

one ofsa'id lever-actuating devices being directly connected to and displacing one fulcrum of a lever and another ofsaid lever-actuating devices beingdirectly connected to and" displacing fulcrams'of two levers.

6.- Acode controlled printer comprising a printing d'evice' and means for selecting a character on said-device, including a'plurallty of levers, means linking the levers together to form an aggregate motion linkage and including a flexiblemember 1?. connecting end fulcrums of two levers and means for maintainingthe flexible member under tension, a plurality of selectively operable magnets, and aplurality'of lever-actuating devices each responsive to. the operation of one of said magnets for displacing a; fulcrum of a lever.

7. A code-controlled printer comprising a printingdevice and means for selecting a character on said device including at least two links longitudinallymovable in substantially parallel adjacent paths, at least threelevers with the intermediate fulcrums of two of said levers connected toone of said links and the intermediate fulcrum of the other of said leversbeingconnected to the second link. a connection between-one end of the two leversfulcrumed on the first link to the corresponding end of the lever fulcrumed on the second link, a connection between the second end of the first lever andthe corresponding end-of the third lever, a connection/between the second end of the third lever and the printing device,

a plurality ofselectively operable magnets, and devices operable in response to the operation of.-

arms and on which the flexible bands wrap and unwrap;

9. A printer'as set forth in. claim '7 in which the first lever is located between the other two.

10. A printer as set forth in claim 2 in which at least two of the levers have arms of different lengths.

11. A- code-controlled printer comprising aprinting: device and means for selecting a char-- actor on said device including a plurality of levers,

meanslinking the levers together to form an aggregate motion'linkage, a series of selectively actuated magnets, means operated by the magnets ior differentially actuating said linkage including links movable in parallel side-by-side paths and each engaging a-levcriulcl'um and operated by means includingone of said magnets, and means, including a magnet controlled cam for shifting one of said linksand the fulcrum engaged thereby. 12. The combination according to claim '7 wherein each of said links is spring-urged to "a normal position when said magnets are deenergized.

LADISLAS KOZMA. GEORGES XAV'IER LENS.

REFERENCES CITED flheio'llowing references are of record in the file of this patent:

. UNITED STATES PATENTS Great Britain Nov. 25,5 1941--

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