US1710751A - Typewriting machine - Google Patents

Description

April 30, 192.9. R. voN REPPERT TYEWRITING MACHINE Filed July 1, 1927 2 Sheets-Sheet April 30, 1929 R. voNV REPPERT 1,710,751

TYPEWRITING MACHINE Filed July 1, 1927 2 sheets-sheet' 2 /nvenfan' @MW-a by (W f4/fa ey.

Patented Apr. 3o, 1929.

UNITED `sT-"a'rlazs 1,710,751 PATENT oFFICE.

BICHAB) Vollv BEPPERT, OF HARTFORD, CONNEUIICUT, ASSIGNOB T UNDEBWOOD ELLIOTT-FISHEBCOHPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

TYPEWBITING MACHINE.

Application Bled J'nly 1v, 1927. Serial H0.202,792.

The present in vention relates to typewriting machines and more speclfically to type-bar actionsof that class where the depression of the key operates through inter- 5 mediate connections to lift the type-bar from its pad and project the type-end against the front face of the laten to type.

Machines of this character, which have obtained commercial supremacy,dependupon the staccato blow at the key to drive a type-head under a momentum, augmented by v.accelerating connections, to strike the face of the platen the quick, sharp blow that develops the noisy click so objectionable in any place where the machines are in use.

One feature of the present invention employs a standard type-bar swingable from a horizontal state of rest,`upwardly and rearwardly to strike the front face of a caseupper case characters; the type-bars `being uniformly arranged in radial planes, mounted as a series upon' a pivot-wire carried by a vertically-disposed radially-slotted segment in a conventional manner. .Each type-bar includes the unit-assembly of'connected parts forming al succession of toggles, oneend of one toggle connecting with the type-bar and the other end thereof pivotally anchored to the frame. These connecting parts co-operateto lift the type-bar from a pad to the platen by a decelerating translation of motion, due to the straightening out of the toggle-elements at the instant of the typeimpact at the platen. These connections per se promote an easy but slow movement of the type-bar of great power, and, at the instant of type-impact, the straight-line positions assumed by the parts serve to retard and arrest any momentive energy in the type-head, which results in a pressureimpact of the type-face against the platen instead of a sharp blow. To preserve these features and speed up the transmitted accelerated effect upon the type-bars motion, accelerating elements intermediate the keys and the type-bar lifting linkages are employed so that, as the deceleratinv effect on the type-bar decreases the speed o its movement, the accelerating effect of the key-lever movement increases the speed of the lifting linkages, and the resultant is a light, snappy, compressing type-bar movement that ma res its typing impact quietly and positively pivotal anchorage on the frame.

shiftable platen to type in either lower orV blage ofthe type-bar and its connected de- A -celerating lifting linkages as a unit, which units may be assembled into the machine upon segment-wires for fu-lcrums with each assembled unit assuming the same radial plane predetermined for the type-bar towards a common typing center that provides for a straight line of transmission from its Each typebar 'linkage has a key-actuated means that includes a pair of accelerative rolling or wiping contact bell-crank levers, one bellcrank positioned directly over its associated key-lever for a vertical straight-line pull, and the other bell-crank aligned verticali to the first bell-crank to coact therewith w ile the free ends thereof, as a series, progressively vary in height to align with a ivotal point on its associated linkage-mem r of the type-bar for a straight-line .transmission of power through a link that is .self-adjustable to the vertlcal planes of the bell-cranks and the radial planes of the type-bar linkages. y The whole train of transmission from the key-lever to the type-bar being laid off along straight lines as with four banks of strai ht parallel key-levers, forty-two straightine, radial type-bar linkages and straight-line transmissions of motion from part to part provide a type-bar action that is practically free of side stresses so colnmon in front-strike type-bar actions Vwhere a toggle-action operates to raise `a. type-bar to type.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure 1 is a vertical skeleton lay-out of the type-bar at the middle of the segment, the type-bar and connections being shown in normal positions in full lines, and in typing positions in dot-and-dash lines.

Figure 2 Vis a det-ail view of the extreme outside bell-crank, its key-actuated lever and its link-connection to extreme outside barlinkage.

Fi ure 3 is a vertical cross-section through the rame looking from the front of the machine, showing the relation of the keylevers and bell-cranksto the radial positions of the type-bars and their linkages.

The keys 10 are arranged in four banks and each key provided with a key-lever 11 that assumes the form of a U, one leg thereof, as 12, forming thel stem of the key and the other leg, as 13, terminating at a horizontal fulcrum-wire 14 mounted in the frame 15 of thevmachine. The key-levers 11 are disposed in parallel planes and spaced ofi' at their rear ends by slots 16, while a front comb 17 provides a forward guide for the up-and-down movement of the keys. This U-shaped yformation of the key-levers, taken as a series, forms a transverse pocket within which an actuating mechanism for the type-bars is arranged, in condensedrela tion, to reduce the height of the machine, and further provides that the vertical dip of the keys 10 shall be practically in straight lines through the elevation of the fulcrum 14 to the horizontal plane of the keys, and

hence there is less interference between the.

depressed key and the adjoining keys, as heretofore, where the fulcrum is at the rear nd of a straight key-lever.

Between the two side walls 18 of the frame 15, and adjacent the top `edges of the key-levers 11, there may be secured a straight cross-bar 19 having open slots 20 cut crossways of the bar at the upper edge, with the slots spaced and aligned to the keylevers 11. Preferably at the rear face of the bar 19 a slot 21 is cut longitudinally of the bar to provide for the entrance of a fulcrum-rod 22 that may be secured therein by suitable screws threaded into the bar to bear upon the ends of the rod. Within each slot 20 a sub-lever, having two arms 23 and 24, is assembled and held therein for a free rocking movement by the fulcrum-rod 22 passing through a perforation of the lever.

This sublever may be formed of sheet metal to rovide that the edge of the arm 23 thereof be bent over at right angles to form a fiat arcuate face 25 to serve as a tread for purposes to appear. The arm 24 ma be pivotally connected to a link 26 pivota ly secured toa key-lever at 27. y Y A bar 28 Vmay be secured to the side walls 18 to lie parallel to the bar 19 and formed with open slots 29 and slotted longitudinally to receive a fulcrum-rod 30 secured therein in a manner described for the rod 22. Within each slot 29 a bell-crank 31 is assembled to rock upon the fulcrum-rod 30, and each bell-crank includes two arms 32 and 33. The arm 33 has an arcuate-,edge formation 34 to b ear against and be wiped by the arcuate face 25 of the arm 23. The relation between these two arms 23 and 33 provides for an acceleration of motion between the two arms in a well-known manner. A suitable s rino 34 may be provided to restore each eyever to a normal position against a pad 35. Y 36 indicates a segment-bar secured atthe ends thereof to the side walls 18 and having slots 37 cut across the front face thereof that radiate from a common point at or just under the typing position. rIhe front face is further provided with an arcuate slot 38 to receive a curved fulcrum-wire 39 secured therein in the usual manner.v Within each slot 37 there is assembled to pivot upon the wire 39 a pair of links 40 having a combined thickness to fill the slot for a free rocking movement. These links 40, after leaving the segment-bar 36, are offset or spread.

apart to embrace a lever 41 at their upper ends, the lever being swingable upon a shouldered stud 42 that also binds the free ends of the two links together.

43 indicates a segment-bar slotted radially across its rear face and provided with a curved fulcrum-wire 44 upon which and within said slots there is assembled one end 45 of a T-shaped lever having two other arms 46 and 47 depending from said fulcrum-wire. The arm 46 is pivotally secured to one end of the lever 41, and the free end of the arm 47 is pivotally secured between two links 48, as upon a shouldered stud 49,

from sheet metal and takes the 'form of a truss that includes the straight member 52 i joinable at both ends to angular members 53, forming an apex at the point of the connection 51 to the links 48 and reinforced by a tie-bar 54 that assumes a position substantially in line to the line of pressure from the actuating links 48 when the'type-bar is at' a typing position, to prevent any spring of the open type-bar as it makes its im ression under pressure. The outer end of tiie typebar may be provided with a plurality of types 55 and may normally restv upon a sound-deadeningv pad 56 supported byI the segment 43.V The inner end of the type-bar may be perforated to receive a fulcrum-rod 57 mounted in a slot 58, and each type-bar guided to a common printing point by the sides of the radial slots 59 Icut across the front face of the segment 60 in a well-known manner. The type-bars have a working fit llt) within the slots 59 to provide a free s'wlng- I in planes parallel to the key-levers 11; that,

as the position of the type-bar and `its intermediate connection to the links 40 climb the sides of their segments from the middle position at Figure 1, `the length of the arm 32 progressively increases to the length shown in Figure 2, where the arm 32* indicates the height for an extreme side type-bar, and that the arm 24 is correspondingly lengthened at 24to provide for the'equalization of transmittedv motion from a uniform dip of the key-'lever to the positions of the segmental type-bars.

It is an advantage that the type-bars ,and all the connections to the links 40 be uniformly the same and that the piv'otal connections 63 to the links 40 be uniformly thev same distance from the fulcrum-wire 39 for all the links for production purposes and to avoid confusion in assembling. It is lalso an advantage to provide a single adjustment between two of the parts to com ensate for variations in manufacture. To t iis end, an adjustable connection is provided between the links 40 and the arms 32 of the bellcranks that includes a rod 65 flattened at 66 and erforated Yat the end to pivot upon a shouidered stud between the two links 40, as indicated at 63, and a threaded screw end 67 to enter a threaded hole in the end of a spring-clip 68 and arranged in a well-known manner to snap into a perforation in the free end of the arm 32. The threading of the screw 67 into the clip 68 provides an adjustable connecting means which provides that the type-bars may be adjusted to lie upon the pad 56 and the key-levers 11 be springpressed against the pad 35 Without vibratory tensions in the intermediate connections. l

It will be noted at Fi ure 3 that the arms 32 assume vertical para el planes and that the pivotal osition63 on the links 40 bi- Asects these p anes at points that are radial to the typing position; hence, the pull of the connections 64 is in straight lines, and the usual. manner of oisetting or fanning the upper ends of the arms 32 to bring these two polnts into alignment is avoided. Furthermore, the sections 66 of the connections 64 having a free turning movement through the WhenV a key 10 is depressed to rock its l lever 11, the connection 26 vibrates the arm 24 to rock about the fulcruml 2 2 to rock the arm 23, while the arcuate tread 25 engages the arm 33 of the bell-crank at a bearing point near the fulcrum 22 and distant from the fulcrum 30, and, as the arm 23 rises to the dotted position of Figure 1 for the end of the key-stroke, this lbearing point between the two arms 23 and 33 progressively creeps towards the ulcrum 30 of the arm 33 and away from the fulcrum 22 of the arm 23, transmitting a well-known form of accelerating motion to provide an easy initial movement of the key-lever to convey motion to a train of inert parts.- The rocking of the arm '32 pulls upon the links 40 to vibrate the upper ends thereof to drive the lever 41, T-lever`45-47 and links 48 to lift the ty ebar to its typing position. During t is movement of lifting the type-bar, the arm 47v and link 48 become toggle-elements which, in straightenin out, lift and project the type-bar and finaly, as the bar acquires its greatest momentum at the typing position,` the straightenin out of a toggle retards and deceleratest e type-bar against its momentum and transmits a relatively great printing pressure but at a low velocity.

The type-bar performs the printing operation by 'pressure instead of impact, and, to avoid aniylI tendency of the type-faces to blur during t e typing instant,'the arms 32 may be arrested by contact with a bumper or resilient pad 70 secured to the bar 28, and the sudden checking of' these arms by the pad conveys a catapult reaction to the intermediate connections to the type-bar to further accelerate the movement of the type-bar approximately at the instant of typing, andv this reaction may be further augmented by providing the free end of each lever 41 with a weight 71 whose rotary momentum is converte into a straight-line pressure to the lever 45-47 and the-type-bar.

After the togglinvr elements have been brought to a state o? rest, as indicated by dot-and-dash lines in Figure 1, there are reactionary forces brought into play to break the to gle due in part to the sudden checking o the arms 32 by the pad 70 andthe recoil of the weight 71, and by the springs 69, to quickly remove the type from the typing position.

It will be noted that the type-actions are controlled from a standard keyboard with a single case-shift; but operating motion is transmitted to each type-bar from a uniform touch and dip of the keys; that each ty ebar is provided with a ylifting toggle t at becomes straightened out at the typing position; that the type-bar-lifting toggle is actuated by an intermedia/te toggle that becomes straightened out-in straightening out the first toggle; that both toggles are aligned to the same radial plane as their associated type-bar for a straight-line transmission of motion; that intermediate radially-disposed toggles are actuated by accelerating belltype-carriers swingable upwardl cranks arranged in vertical parallel planes that bisect the planes of the toggles at a uniform radial point for a uniform transmission of leverage and in approximately astraight line; that each type-bar and its two connecting toggles may be assembled as a stock unit and assembled radially to their segments as units; that the keylevers and accelerating members arealigned in parallel vertical planes predetermined by a standard spacing of the keyboard; and that the keylevers are U-shaped with a pivot at one end and a key at the other to provide for a substantially straight up-and-down movement of the key in typing without the interference from adjoining keys so manifest in the usual four-bank keyboard.

p Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

l. In a front-strike typewriting machine having a seriesI of horizontally-disposed and rear-- wardly to type from a vertica ly-disposed radial segment, and a series of parallel horizontal key-levers therefor, the combination of mechanism for conveying motion from the horizontal ke -levers to swing the vertically-radial stri ing type-carriers, includ-l ing a pair 'of connected togglino' linkages aligned to the swingingplane o its typecarrier, one toggle operative to swing the type-carrier to type and another toggle operative to drive the first toggle, and mechanism supported upon strai ht horizontal supports and connecting the ey-levers and the driving toggles, including bell-cranks driven one way by the key-leversand permanent connections from lthe bell-cranks to the driving toggles.

2. In a front-strike typewriting machine having a series of horizontally-disposed type-carriers swingable upwardly and rearwardly to type from avertically-disposed radial segment, and a series of parallel hori- 4. zontal key-levers therefor, the combination of mechanism for conveying motion from the horizontal ke -levers to swing the vertically-radial stri ing type-carriers, including a pair off connected togglnnf` linkages ,aligned to the swinging plane o its type- `carrier, one toggle operative to swing the type-carrier to type and another toggle operative to drive the first toggle, and mechanism pivotally supported in straight uniform planes -and connecting the key-levers and the driving toggles, including vertical bell-cranks operable by key-lever-actuated olie-wayaccelerating connections and um'- iffwfmi form horizontal connections from the bell-V cranks to the radial driving toggles.4 t

3. In a front-strike typewriting machine having a series of horizontally-disposed type-carriers swingable upwardly and rear- 7o wardly to type from a vertically-disposed radial segment, and a serieskof parallel horizontal key-levers therefor, the combination of mechanism for conveying motion from t-he horizontal key-levers to swing the vertically-radial striking type-carriers, including a pair of connected togglinv linkages aligned tothe swinging plane o its typecarrier, one toggle operative t0 swing the type-carrier to type and another toggle op- Y erative to vdrive the first toggle, and mechanism intermediate .the key-levers and the driving toggles pivotally supported in straight uniform planes and including vertical bell-cranks swingable about a straight'S of a uniform"length between each bell-crank to a drivmr toggle.

4. In a tfront-strike typewriting machine having a segmental series of horizontallydisposed type-carriers swingable upward y and rearwardly to type and a series of key- I levers therefor, the combination of mecha- ,nism for conveying motion froin the key- 'levers to swingl the type-earners, including` a train of connected -radially-disposed toggling linkages for each type-carrier, one m0 toggle operative to swing the type-carrier to typev and another toggle operative to drive the first toggle, and mechanism intermediate the keys and the driving toggles, including vertical bell-cranks, horizontal connec-106 gle and a sub-lever intermediate the tions from each bell-crank to a driving togbel cranks and connected tothe keys. Y

5. In a front-strike typewritmg machine having a segmental series of horizontall 110 disposed type-carriers swingable upward y land rearwardly to type and a series of key levers therefor, the combination of mechanism for conveying motion from the keylevers to swing the type-carriers, including 115 a train of connected radially-disposed tog-v gling linkages for each type-carrier, one

toggle operative to swing the type-carrier to type and another toggle operative .to drive the first toggle, and mechanism intermediate the keys and the driving toggles, including verticalbell-cranks, horizontal connections fromeach bell-crank to a driving btg- -gle and a sub-lever intermediate the h cranks and connected to the keysz said sublevers having a one-way connectlon yto the bell-cranks, including motion-accelerating. Y

wiping faces. 4 c 6. In a front-strike' typewrlting machine having a segmental series of horizontally- 139 disposed type-carriers swingable upwardly an rearwardly to type and a series of keylevers therefor, the combination of mechanism for conveying motion from the keylevers to swing the type-carriers, including a train of connected radially-disposed toggllng linkages for each type-carrier, one

toggle operative to limit the typing move-1 nient of the type-carrier and another toggle operative to drive and limit the movement of the first toggle, and mechanism inter-v mediate the keys and the driving toggles, including vertical bell-cranks of varying llengths and horizontal con-nections of uniform lengths between the bell-cranks and the driving toggles.

7. In a front-strike typewriting machine having a segmental series of horizontallydisposed type-carriers swingable upwardly and rearwardly to type and a series of keyy levers therefor, the combination of mechanism for conveying motion from the key-levers to swing the type-carriers, including a train of connected radially-disposed toggling linkages for each type-carrier, one toggle operative to limit the typing movement of the type-carrier and another toggle operative to drive and limit the movement of the firstl toggle, mechanism intermediate the keys and the driving toggles, including verticalbell-` cranks of varying lengths and horizontal connections of uniform lengths between the bell-cranks and the driving toggles, and means to jointly arrestthe typing stroke of the keys and the driving movements of the bell-cranks to arrest theY driving toggles at 4the impact of the types in typing.'

intermediate the keys of the driving toggles operative to accelerate the movement of the type-carrier, vincluding bell-cranks having link-connections to the driving toggles and sub-levers connected to the key-levers, each sub-lever having a wiping tread to engage its associated bell-crank.

9. In. a front-strike typewriting machine having a vertically-disposed segment with' a series of type-carriers swingable upwardly and rearwardly to type and a seres'of horizontally-disposed key-levers therefor, the

combination of means for conveying motionV from the `key-levers to the type-carriers, a

.actuate each type-carrier uniformly from a pair of vertically-disposed segments below the type-carrying segment, toggle-links anchored to one segment and connected to each type-carrier, other toggle-links anchored to the other segment and connected to drive the 70 first-mentioned toggle-links to lift the typecarrier, and connections between-each driv- A ing toggle and a key-lever.

10. In a front-strike typewriting machine' having a platen, a swingable type-carrier and a key-lever therefor, the combination of mechanism connecting the ty -carrier and .the key-lever for ty infr, vinc uding a pair of co-operating buc led-up toggles to be straightened out, one toggle operatively connected to swing the type-carrier when straightened outfandl an actuating toggle operative to straighten out the first toggle when saidactuating toggle is straightened out, and mechanism intermediate the .key and the actuating toggle, including a` bell-crank having a link-connection .to said toggle andv operatively connected to the key. t

11. In a front-strike typewriting machine having a series of segmental type-carriers pivotally disposed for a.l standard`` radial spacing to type at a common center and ha keyboard of standard form having key-levers disposed in horizontal, straight, parallel planes from the keys, the combination of means for conveyin motion from each key-V lever to its associate type-carrier by straightline transmissions without side stresses, said means including a decelerating linkage mounted toassume the same radial plane of the t pe-carrier, accelerating bell-cranks vertica y disposed in the planes of the keys., horizontal connections between each bellcrank and its linka the relative elevation of each connection eing predetermined by105 the position of the type-carrier on the segment, and connections between the key-levens to variably accelerate di'erent bell-cranks to uniform dip of the keys. 110

12. In a type-bar action for a typewriting machine having a series of parallel yhorizontal key-levers and a series of horizontallydisposed pivoted type-bars swingable upwardly and rearwardly to type, the combina- .115 tion of motion-transmitting mechanism intermediate the key-levers and the type-bars, including accelerating elements connected to -each key-lever and swingable in the -plane of said lever, and a pair of deoelerating toggles cooperative in lconnecting the acceleratingl elements with a type-bar and swingable in the radial plane of said type-bar, the accelerating and decelerating elements V providing separate straight-line motions that co-operate at a point determined by the segmental' angle of the `type-bar. y

13. In a type-bar action for a typewritng machine having a series of parallelhorizontal key-levers and a 4series of horizontally- 130 disposed pivoted ty e-bars swingable upwardly and rearwar y to type, the combination of motion-transmitting mechanism intermediate the keyJeversland the type-bars, including accelerating elements connected to each key-lever and swingable in the plane of said lever, a pair of decelerating toggles cooperative in connecting the accelerating ele- -vments with at pe-bar and swingable in the 10 radial plane o said type-bar, the accelerating and decelerating elements providing separate straight-line motions that co-operate at a point determined by the segmental angle of the type-bar, and a connection between the two straight-line moving elements operative to compensate for the varying angles of the type-bars for Va non-side-stressingr translation of power in driving a type-bar to type.

RICHARD VON REPPERT.

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