US1756961A - Typewriting machine - Google Patents

Description

" May 6, 1930.

B. c. sTlcKNEY TYPEWRITING MACHINE Filed Deo. 3, 1927 e sheets-sheet May 6, 1*930- B. c. sTlcKNEY 1,756,961

` TYPEwRITmG MACHINE Filled Dec. 3, 1927 e sn'ets-shee't 5 w /ff @l mumnnll i H/ i H756, v

Patented May 6, 1930 UNITI-:o sraxrlssv PATENT. oFFIoE BURNHAM C. STICKNEY, OF HILLSIDE, NEW JERSEY, ASSIGNOR TO UNDERWOOD ELLIOTT FISHER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE TYPEWRITIN G MACHINE Application filed December 3, 1927. Serial No. 237,368.

This invention relates to the type-actions of type-writing machines.

An object of the invention is to produce a simple, Compact and eflicient system of radially-arranged frontstrike type-actions which shall produce satisfactory impressions upon the work-sheet with a minimuml of noise. It is alsoan object to organize the type-actionsso as to make it practicable to build them into a standard typewriting machine in place of the vordinary noisy typebars. It is an Object to render the key-touch agreeable, and, further, to provide suitable means for vibrating the ribbon, and operating the ribbon-feeding mechanisms andthe` carriage-escapement mechanism.

Preferably there is employed an arcuate system of folding type-linkages, Working in planes that radiate downwardly and outwardly from the printingpoint, each linkage having upper and lower case characters; the types preferably lying face downward at the rear ends of the type-linkages, and rising as they unfold, and then moving rearwardly to deliver the type-impressions. The unfolding movementA of the type-linkage is effected at relatively high speed; and for the remainder of the printing stroke, the speed of the type substantially decelerates, said remainder being a. backward Hoat of the typecarrier on the links, to reach the platen. The type-linkage includes a rear drive-link and a forward guide-link, both fitted upon the framework of the typewriter, and a typecarrier which is floated upon the tips of said links and is normally in folded cumbentposition.

A feature of the invention is the means whereby the inertia of the type-carrier 1s easily overcome by giving thekeya maximum initial leverage upon the type-linkage, and gradually decreasing the key-leverage substantially throughout the unfoldlngmovement of the type-linkage, and thereafter maintaining the key-leverage nearly constant throughout the remainder of the printing stroke. At the concluding portion of the print-ing stroke, while the type is wlthrn say a hundredth of an inch of the platen, 1t 1s moving at greatly decelerated speed, and prlnts very quietly, due to such reduction in speed. When close tothe platen, the type itself moves at 'about ene-half or one-third ofthe speed of the free ends of said links,'and said links at that time'move at a speed which'is less than the maximum unfolding speed of the type itself. The momentum of the.9per

ators hand, when arrested 'at the bottom of the key-stroke, is utilized in pressing the typel against the platen, Aor the paper thereon, they leverage of the key upon the type being relatively great as compared with standard type-.striking machines) at the moment of.

printing. The momentum of the entire typeaction is also of assistance in compressing the type against the paper, to produce a clear impression and to conduce to satisfactory mani- 4folding power.

. touch, and yet avoid a high-speed, noisy typeimpression. To this and other ends, theI keys are mounted upon parallel levers which are vin the form of rearwardly-extending bellcranks which turn upwardly at their rear ends and are pivoted at'thcir tops. The upwardly-extending arms swing back against upstanding sub-levers to operate the latter. Said sub-levers are pivoted at their lower ends upon the framework, and at their upper ends are connected forwardly to the typelinkages. The vertical varms of the keylevers are arranged to roll down upon the sub-levers.

This invention includes improvements upon the machine disclosed in my Patent No. 1,717,527, dated June 18, 1929.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure l is a longitudinal sectional elevation taken about centrally of an Underwood also it-he separate universal bars, one for o'perating the carriage-feed, and one for operating the ribbon vibrating and feeding mechanism.

Figure 2 is a front sectional elevation of the principal parts seen at Figure 1.

Figure 3 is a sectional detailed plan 'of the radially slotted segment, in which are detachably secured the individual brackets which carry and guide the type-linkages seen at Figure '8, this being the preferred manner ofA mounting the linkages.

Figure 4 is an elevation showing the yprinting position of'one of the key-actions seen' at Figure 1.

Figure 5 is a -front sectional elevation corresponding generally with Figure 2, but lshowing the preferred form of type-actions and mountings which are seen at Figures 3 and 710.

Figure 6 is a sectional elevationof portions of the framework with the type-bracket'segment seen at Figure 5.

. ing in full lines the preferred form of typeaction in printing position, and showing in dotted lines the same in normal position. In this form, the type-actions are mounted individually upon brackets which are set into radial slots in a segment, 'a portion of whichis seen at Figure 3, and another view at F igure 9. l A

Figurev9 is a sectional front elevation of a slotted segment having brackets orhangers in the slots and type-linkages pivoted upon the brackets.

Figure 10 is a perspective sectional view ofthe guide-link portion of one of the typelinka'ges, and the bracket upon which it is mounted.

Figure 11 is a sectional side elevation corresponding with Figure 1, and showing ribbon Vibrating and feeding mechanism in normal positions.

Figure 12 corresponds with Figure 11, but shows the parts in printing positions.

Figure 13 is a detail of the ribbon-winding mechanism, and is to be read in connection with Figure 11. l Figure 14 is a diagram showing parts similar to Figure 8, normal positions being shown byvfull lines, and the dotted lines showing the .positions about midway of the type-unfoldingl movement, and also the positions at the region .where the upward type-unfolding movement changes fully to a rearward floating movement.

Keys 10 surmount stems 11 of V-shaped in upwardly-extending arms 13, vv vhich are pivoted at their upper ends upon a transverse, horizontal fulcrum-rod 14 arrangedat 'l about the level of the keyboard, so that .the

'link 22, 'a forward upstanding guide-link 23,

and a folded cumbent type-'carrier or float l24, having upon its tip a doubleA type 25.

The system of type-linkages is narrower than the system of key-levers 12. The width of the system of sub-levers 19 at the top is about equal to the .width of the system of type-linkages.. Towards their lower ends, said sub-levers fan out frornside to side Vof the machine to about the width of the keylever-system; 'and their fulcrum-rod 21 is bowed downwardly, and at their lower ends said sub-levers 19 work in radial slots 26 formed in a fulcrum-bar 27. Said sub-levers 19 are all straight, and, viewed from the front, radiate upwardly and inwardly from the broadly curved fulcrum-'bar 27. Said sub-levers 19'extend upwardly behind and above the horizontal transverse row of keylever-arms 13; and at 28 the tops of the sublevers are pivoted to the rear ends of the pull- "links 2O at points above the key-levers. Some of the sub-levers at their upper portions curve forwardly over the key-lever-tips, as at 29.

' The upright arm-portions 13 of the keylevers form treads or rocker-portions to roll down along the treads 18 of the sub-levers 19;

and these portions 13 are bent more or less inwardly to form diagon als, producing a con.- verging arrangement, as seen from the front, Figure 2, to agree with the arrangement of the sub-levers 19. To guide the levers andalso to keep the rocking edge of each in registry with its associated sub-lever, there are provided for the key-levers, in addition to the vertical slotted guides 15, a Vertical guidecomb 30 for the elbow-portions of the keylevers (so that th arms 13 are guided at top and bottom) and a vertical guide-comb 31 for the key-levers just-in rear of the keyboard. No trouble arises from lateral binding or twisting of the key-levers, even though the system of key-levers has less width at the fulcrums 14 than at the elbows 32.

At their upper ends, the sub-levers 19 are provided with tips 34 to work in a curved i guide-comb 35, which is cooperative with the ower radial slots 26 to guide thesub-levers. The sub-levers are of graduated lengths and form a system which is curvedvat its upper end to conform generally with the curvature of the system of type-linkages; while the system of key-levers extends' horizontally across the machine.

The pull-links 2O include turnbuckle-portions 33, to make them extensible, for securing proper contact and coaction of the rolling v wardly and forwardly to the forward guidelink 23. l

The pivoting of each of the rear drive-links 22 to the type-carrier or iioat'is indicated at 36. The pivoting' of the forward guide-link 23 to the same.type-.carrier is indicated at 37.

The drive-links 22 in one form of the invention are` pivoted upon. a rear fulcruin-rod 3S which is curved concentrically with the printing point at 43, said rod being fixed in a segment- 39 which has radial guide-slots 40 forthe hub-portions of the drive-links; the forward ends of the pull-links 20 extending forwardly over saidsegment 39. For the drive-links 22, a slotted guide or comb 4l may be fastened by screws-42 to the framework, and extend rearwardlyv and upwardly over the segment 39 to a point in the rear thereof,

links 23, and also curved concentrically with the printing point 43. By means of the combs 41 and 46, the. links and the type-Hoats or carriers are constantly guided, so that t-hey may move freely and accurately to the point where the types enter 'the common center guide at the front of the platen. The types at the side of the system may be also supported in part by the drive-link 22 at points thereof near the fixed guide-comb 41.

A curved or segmental dust-shed 47 may be secured to the front ofthe slotted segment 39 by screws 48, and extend rearwardly over the segment 39, to keep the slots free from particles that fall from the work-sheet. The drive-link 22 near its hub-portion may have a goose-neck portion 49 formed to clear the dust-'guard 47 in front thereof.

The pivotal attachment 50 of thev pull-link 20 tothe drive-link 22 is above the dustguard 47. i y

When the drive-'link 22 is pulled rearwardly by the link 20 and the sub-lever 19 at the operation of the key 10, the drive-link swings upwardly to about .a vertical position, thus unfolding the type-linkage until the type reaches a point forwardly of the platen. From this point the type-carrier is iioated backwardly upon the links 23 to the platen, by which itis arrested.

The key-levers may be individually returned to normal positions by means of a transverse horizontal row of coiled diagonal springs 51, extending forwardly and downwardly from the upper-,ends of the leverarms 13, and anchored at their lower ends upon a bracket 52 fixed upon the framework. The type-linkages may be individually returned by .means of radial diagonal tension springsB, attachedvat their upper ends to the drive-links 22, and at their lower ends to a bracket 54 also secured to the framework. The leverage of each spring 53 decreases during the printing stroke. Each of the drive-links may be provided with a guiding ear to maintain engagement with the guide-comb 41 at the last portion of the printing stroke. i

As seen from the front at Figure 2, the

type-linkages converge directly to the printing point 43, `and the segment 39 and the slotted guide-link-segment 56 are curved con* centrically with said printing point; while the sub-leversare less convergent than the type-bars, but at their upper ends stand about directly in rear of and levelI with the points 50 where the pull-links 20 engage the drive-linksy 22, so as to conduce to etliciency and avoid appreciable side strain or binding. The width of the system of sub-levers at their upper ends is about equal to the width ofthe system of drive-links 22 at the points 5() where they are pivoted to the pull-links.

Each key-lever tread 17 may be extended downwardly, if desired, at 57, to carry the rolling contact down as far as desired in each instancetowards the pivot 21 of the sublever. The springs 51 hold the key-levers up against a cushion or rest 58, while the springs 53v pull theV types down against a curved cushion or rest 59. 'T he turnbuckles 83 are individually adjusted to secure the desired contact of the arms 13 and 19 at the beginning of the key-stroke, and to compensate for unevenness in the normal positions ol' types 25 or levers 12. The sub-levers fan out toward their lower ends in an arc upon a common fulcrum-wire, said lower ends being l lower than the key-levers. The upward arms of the key-leversare also made divergentto coincide with their respective sub-levers.`

The key-levers are guided at their -pivots and also attheir elbows, andalso-at their key-ends to avoidside strain or binding at the sides of the system. All of the sub-levers move freely in their converging planes-and are free from binding lor side strains.

to a point above the level of the pivot 36 as.

the type approachesthe platen, Figure l. -At thistime, as both links about complete their rearward swing, the guide-link 23 is on the down-swing, and carries the forward end of :l the type-carrier downwardly, whereby the type-carrier tends to turn towards the left at Figure 1, around the point 36; or, in other words, the type itself is retarded or del celerated, so-that the speed of the type, as

it is almost in contact with the platen, may equal only about one-half or less of the speed of the link-pivots` 36,37. The speed of the type is brought down'so that it is arrested vwithout objectionable noise. However, the

shock of the slowly moving type against the platen or paper is heavy, because the platen must serve to arrest the finger-and the hand of the operaor, which is still driving down upon thedepressed key 10. The type' and platen must arrest the variousparts ofthe type-action as well, including the key-lever, the links, and the type-carrier itself. At the samev time the key has enough leverage to enable the pressure of the operators. hand to aid in pressing the type against the platen. From all of these causes, a satisfactory impression may be secured, without giving the type the quick blow which is so noisy in common typewriters.

This arrangement of the linkage gives the type-carrier such a path as to secure clearance between the same andthe platen-paperfeeding devices and other adjacent devices in the typewriting machine, and also gives a desirable relation between the upwardly-unfolding portion 'and the rearwardly-floating portion of the printing stroke of the typecarrier.

In order to lnake the operation of the key easy and to avoid the shock to the linger, the key is given a great leverage upon the typelinkage at the beginning of the printing stroke. For this purpose, the point of contact between the key-lever arm 13 and the sub-lever 19 is normally relatively close to the key-lever pivot 14. Ease of key-touch may be preserved beyond the initial portion of ,the key-depression, by arranging for the contact between said levers 13 and 19 to remain quite near the pivot 14 of the key-lever" depression. As the type gathers headway,

however, the Vpointgof contact vbetweensaid levers 13and 19 is gradually shifteddown farther from the key-lever pivot lll, and nearer to the pivot 21 of the sub-lever, thereby continually decreasing the leverage of the key upon the type-linkage, without making the key-touch harsh,'and tending to store up in the type-linkage some energy imparted by the hand of the operator. This decrease of leverage may continue untilthe type-linkage is substantially unfolded, and the type-carrier begins its relatively-slow rearward printing movement. From this time on, it is not necessary to decrease rapidly the leverage of the key upon the type-linkage, but rather it is a `desideratum to maintain the leveragenear the point where the movementof the type- .carrier changes from its upward unfolding movement to its rearward printing lmovement. It is desirable,` at the actual Contact of the type with the paper. that the leverage of thekey upon the type'shall vremain fairly good, so that pressure on the key may aid in producing substantial pressure of the type againstzthe platen at the instant of arrest. Moreover, it is desired to avoid speeding -up of the type at theconclusion of the printing stroke of the key. For these reasons, the leverage of the key upon the type-action does not need to be decreased substantially during the rearward floating of the unfolded type-carrier, that is, during the time when the type is within say one-half an inch of the platen. The weight of the moving type-linkage may, however, be so great that it will effectually resist the tendency of the hand to speedup the linkage near the conclusion of the printing stroke, even if the key-leverage upon the drive-link is diminished at this time beyond the point illustrated.

.The type-carrier is so mounted upon its llnks that in printing position the guidelink may form an obtuse angle with the typecarrier, that is, with a line drawn from the .type to the joint of the type-carrier with the .guide-link, and liability of spring of the guide-link rearwardly past its true position when the .type 1s arrested by the' platen, may be avolded. Hence the type delivers a solid,

clear-cut impression.

or excessive speed of the type-action, and

unnecessarily heavy type-impressions and unnecessary noise of impact. At first there is but little rolling of one lever along the other, so that theleverage of the key remains great until the type-carrier 24 has moved up a substantial distance. Then the key-lever arm 13 rolls upon lthe sub-lever tread 18, thereby graduall decreasing the key-leverage, until nearly t e completion of the unfolding or high-speed portion of the travel ofthe type 25, whereby undue resistance of the key to the linger-pressure Vis avoided and :the touch 1s kept easy, and thetype-linkage is notiunduly speeded and does not acquire undue' momentum. During the remainder of the A upon the type shall be as high as practicable to secure sufficient pressure of the type upon the platen or paper.

Av substantial advantage is gained by the provision of one lever rolling upon another lever, since, by this means, the leverage can be readily shifted, as and when required; the leverageof the key upon the type being say fifteen to eighteen times as greatat the beginning of the key-stroke as at the end thereof. This extraordinary leverage at the beginning of the stroke overcomes the normal resistance of the type carrier 24, the first part v of whose unfolding motion is extremely abrupt, owing'to the manner 1n which 1t 1s sub-lever; the arm 13 and the sub-lever armmounted upon the links 22 and 23; and, inI

addition, the carrier necessarily has considerable size and weight and is therefore heavy.

It will beseen'thatl the downward and up ward movement of the key effects a rearward movement and a forward movement of the 19 standingedge to edge in rear of the typelinkage-s'ystem, or, in other words, thetype? linkage-system being mounted between the keys and the vertically-standing roll-lever arms. simplicity of construction and operation, and accessibility, and produces a mechanism which can be manufactured at low cost and inserted in standard typewriting machines in lieu of the usual key-actions, as, for example, an Underwood standard machine.

It will also be seen that the rolling levers arms 'occupy the lower part of the machineframe, the upper part being occupied by type-linkage, and that the pull-links 20 extend forwardly from the sub-levers and beneath the type-basket 59 to the drive-links 22, whose segment is forward o f the typebasket, and that the type-carriers 24 Anormally lie between the type-basket and the segment 56, which carries the system of guidelinks 23.

The use of a key-lever having a rear elbow pivoted at its upper end and a sub-lever of the third order, pivoted below. said elbow and extending up in rear of said key-lever arm 13 and connected at its upper end to the type-linkage, presents the advantage of eficiency and 'of compactness andv simplicity in manufacture, and affords the further-advantage that the 'sub-lever-system can be This givescompactness and affords fanned out and thus be made at its upper end as narrow as the type-linkage-system, and at its lower end as wide as the key-linkagesystem. There may be a diagonal line of rolling of the key-lever arm 13 upon the sublevers 19 to accommodate said fanning out of the sub-levers, the diagonal line being slight and the key-levers, nevertheless, working in vertical planes without liability of binding from the diagonalposition of the key-lever arms 13, as .viewed from the front of the machine.

It is found in practice that the contact of the type with the platen may be accompanied by more noise than is accounted for by the speed of the type itself or by the hardness of the platen. As the type-carrier 24 approaches the platen, it tends, by reason of centrifugal force, to fiy upwardly bodily from the links 22 and 23. When the type is arrested by the platen, the drive-link 22 tends to continue its backward swing and to carry backthc lower end of the type-carrier, which therefore momentarily tends to swing downwardly and forwardly about pivot 36. This tendency is arrested by theV guide-link 23, which receives a downward pressure from the forward enid of the type-carriergthis down ward pressure being caused, as just explained, by the arrest of the type and by the constant tendency of the type-carrier to turn backwardly around' the pivot 36 andy downwardly at the pivot 37. This sudden change at the pivot 37, from an upward pull of the type-'carrierV immediately prior to printing) to a downward thrust (due to the arrest of the type), causes a knockin the link-joints 37 and 65. This knock is overcome by means of a tension spring .60, which, atits upper end,

may bel attached to the type-bar as shown,

or it may be caught through an axial hole indicated by a dotted circle 6l in the pivot 37, and, at its lower end, may be caught upon a curved bracket 62 fixed upon the slotted segment 56 in which the guide-links 23 vi brate. The springs keep the. oints 37 and 65 constantly closed, avoidingV noise. These springs occupy positions between the guidelinks 23- and the arms 63 of the type-carrier.

This tendency to knock in some forms of the invention may be further reduced by bulging the type-carrier rearwardly at 64, so tl1at,-when the type approaching the printing line, the weight of the bulge-portion 64 will be'on the opposite side of the pivot 36 from the bulk' of the weight of the type-v carrier, so that there is a tendency of the portion 64 to turn the type-carrier in a direction to hold the link'23 constantly down upon its ing and guiding thereof, this-form being op- 'erable by the same'key-lever and sub-lever ar 'and etticiencyin delivering type-1mpres-- action that has been described'.

In thispreferred form, the drive-link 66 is used the same as 22, for unfolding the typelinkage and fioating the type-carrier to the platen; and it is mounted upon an individual pivot 67 corresponding with- 38. A.l short front guide-link 68 is shown corresponding with 23 and pivoted at 69 .at a pointsubstantially higher than pivot 67. The triangular type-carrier 7 0- is pivoted at 7l and 72 to the free ends of said links 66, 68.

The guide-link 68 is'much shorter than 23', makingV a short reach from the pivot 69 tothe y laten and conducingto stability of the typesions. .The elbow-shaped type-carrier 70 forms a triangle lwhose sides are about equal inlength. Owing to this form, it may be of minimum size and maximum etliciency, while, owing to its mounting, its type-end is given sucha lpath 7 3 as to clear the usual paperlguiding devices 74, etc.; While normally the type-carriers compactlyoccupy a position in rear of the links 68 and with the types di- I rectly overlying the pivots 67.' The drive- 'link 66, whose length is about equal to that of the rearvside-of the trian ular type-carrier 70, may swing through su stantially less than ninety degrees; While in normal position line therewith', preferably a little below aline joiningv 69 to 70. vYVith the proportionit extends towards the pivot 69 andabout in ing and mounting aforesaid, and with the "pivot 72 spacedv considerably back of the pivot69, the, type-.linkage is easily started into action, and its ventire .movement isrendered smooth, and the touch upon the keys is better controlled bythe rolling`of the sublevers 19, and the imparting of excessive momentum to the type-linkageI is avoided, tending to quietness of'type striking. There is avoided excessive travel of the type at'any stage, in propio,rtijo'n-,tothe travel of the drivevIn this construction, the speed of the type is substantially7 retarded near the platen, and

especially when it is-a's close as one-sixteenth or one-thirty-second of an inch to the platen. There is shown diagrammatically in straight dotted lines at Figure 8 a position of the linkage, from which it vwill be seen that pivot 71 tion'.

will, at the lastl part of its printing stroke, travel a much greater distance than is traveled by the type or inother words the speed ofthevtype-is relatively or; proportionately greatly decelerated, with resultantl minimizingA of then'oise of impact. This special deceleration is mainlyieected by causing link 68 at this stage to have a much inclined posi- Its free 'en d.V or pivot 72 is moving downwardly as well as rearwardly; and the Obliquity of movement is so great as to cause the car-rier to turn relativelyitowards .the

-overlie a segmental left at Figure 8, about ivot 71, as the latter travels rearwardly in a out a horizontal direction,l Thus, as the type-carrier 70 is'tloated rearwardly uponits pivots 72 and 7l, its

type is given an`independent movement of retardation about the pivot 71thus resulting in substantial deceleration with the result above noted. v A

Preferably, each type-linkage is mounted uponv an individual hanger, designated generally as 75, and inclusiveof a supporting plate or hanger 7 6 and forward and rear arms 77, 78 branching therefrom. A ,The hangers are radial, and each arm 77 carries pivot 69, while each arm 78 carries apivot 67'., -The plates 7 6 are fixed in slots 7 9 ,formed inasegment 80 curvingdownwardly-[andforwardi ly, said slots 79 radiating downwardly and forwardly from the printingl oint 43, and v being so placed that the arms 7 andv7 8 are about equal in length. Thehangers are'held in the slots by means of bolts 81 having heads a shouldered portion 86 on one side, Figure 3, whiclrfits over1 the finished forward tace y' 87 of the segment. When inserting or withdrawing a hanger, the'adjacent nuts 85 may be loosened to ermit the'hange to be lifted out of its slot 9. The bolts have flattened'- sides 88 to clear the hanger-plates 76,v andv permit their endwise insertion and withdrawal while the loosened bolt remains in'pla'ce. f,

It will be perceived that after the adjoining down'u'ntil a shoulder 89.formed 'on one face or side of the hanger-plate abuts against the -upper finished face ofthe segment 80, so thatvthe type-linkage is mechanically located in proper position.

The springs 60,l Figure 8may be pivoted n at their lower ends to'pins90-'provided upon the hanger-'arms 7 8 below the pivot 69, -in such position that the line jof'pull of 'each spring is constantly lapproziim'ate. to a line '105 hangers are Withdrawn, any'boltmay be released by removing its nut, and the bolt witli-` drawn. In inserting the hanger, it is pushed' Joining the pivots 6 9, 72,'so as alwaysl to hold the movement of the linkage.:

One ofthel advantages of the hanger 7 7, 78 is that it permits compatnes's of the linksv 68 said pivots tight, while notunduly affecting v Hfor which the room is restricted, and which must be confined closely sidejbyside, as will be understood from Figure 5. For compacts ness and stiffness. thisv link is folded,y length-v .Y

wise at 91; and it may be given a` U-'s'hape toafford clearance for the spring 60'. Ati/cs.- `upper end the link is formed withoppositeears or forks 92, Figure 10, which bcstride a pivot 93 .of large diameter, having oppo` sitely projecting central stud-portions 94, extending through the opposite ears the studs being riveted or headed over onto 'the ears 92, thus strengthening the link at this region and also forming a thin but ample bearing for the-type-carrier 70, whose hub 95- i's freely confined between the ears 92. 'ln this manner the requisite thinness of bearing is secured, and the links 68 can Work in vthe confined spacewhich they must occupy.

Upward from the hub-portion of the typecarrier projects a guiding nib 96, corresponding with 45, and milled to a' thin condition,

4 and working in one of the radial guide-slots hanger may be provideda horn by which may be `lightly guided the drive-link 66; preferably said-link is provided with an ear 101 bent to one side at Figure 7 and having a slot 102 which embraces said guiding'horn 100. Dust and falling particles may be kept ofi fromthepivots67 by a dust-shed 103 in the formof a segmentcovering all-of said pivots and suitably supported at its ends: the drive-link 66 formed with clearance 49 for said dust-guard 103. f

lAt Figure 14 isshown in full lines Pthe normal position of the type-linkage with the upright key-leverl arm contacting (at 103a) near its fu-lcrum with the upper portion of the roll 18 of the sub-lever. This gives the key maximum .leverage upon the type-linkage, for starting the same easily., This leverage is substantially maintained throughoutl about the first half of -theunfolding .movement of the type-linkage, at'which stage (1053") the key may be halt way down. At this point there begins a very great decline in the rate of travel of the type compared with the/rate of the drive-link 66as the upward unfolding movement merges into'the rearward floating' movement.4 At said point 103b there also begins a' rapid rolling ofthe lever-arm 13 upon the sub-lever 19, until (at 103C) the key has nearly its minimum' leverage upon the type as the latter begins to float rearwardly upon the links. From this lpoint on, the change of leverage of the key'upon the type-carrier is relatively small, the point of application of power of the key-lever to the sub-lever now'remaining near the maximuni distan-ce from-the key-lever pivot ,and near the minimum distance from the sublever .-pivot. -Owing to the reduction in keyleverage, the type-action tends to absorb lthe momentum of the hand of the operator, and

the key tends to slow down. .The drive-link l .66 may' be weighted on its free end portion at 104, andthe' type-carrier itself may also be weighted near its hub-portion 105, these parts now moving 'at 'relativelyhigh speed and increasing the shock of the type against the platen. r1`hus, though the speed of the type is at minimum atthel impact, still it -v must Aassume the burden of arresting the heavy type-'linkage and the hand of the operator, 4so that a' goed impression is secured with a minimum of noise.

At its lowerend each guide-linkGS has ears 106 embracing the thinned upper end 107 of the hanger-arm 78. At this end, the link 68 has a pivot similar to 92, 94 already described, and designated as 108, 109, the opposite stud-portions 109' being riveted over the ears 106 to stiften the link and confineV it upon the arm 78, the'latter vhaving a pivotliole 110 to fit upon the pivot 108.

The platen is mounted upon the usual Underwood platen-shift-trame 111, which .shifts up and down upon acarriage l112,mounted upona guide-rail 113. Upon the framework ot' the .machine is usually, mounteda shiftfra-me 1141' including a shift-rail 114 for sup porting the pleiten-frame 111. The carriage has a rack 115 meshingwith a pinion 116,

connected to an escapement-wheel 117 controlled dby a Apair Vof bevel feed-dogs 118, 119, having a returning spring 120 and a stop 121. To opera-te this Underwood carriagefeeding mechanism,there may be providedr upon thesub-levers 19.*rearwardly directedtappets 122 to swing down about the lpivots 21 against" a universal bar 123, which is in the ,form cfa bail havingxopposite arms `124 that are rigidly connected by a rock-shaft 125. `From this rock-shaft vextends rearwardly an arm 1,26, connected by an extensible thrust-` link 127 to an arm 128 provided upon the olog- .rocker 129, this link being longitudinally slotted at-'its upper endwat 130't'o fit detachably upon an operating pin 131- provided upon an arm 132 of the dog-rocker, said arm lbeing slotted to receive the u-ppeiend 133 ot the link 127. The-upper portion of the linkv has a threaded bottom-shank .i134 screwed down -into the top ofthe main link 127, to permit endwiselengthening of-the link and thereby effect corrective adjustment between the universal bar 123 and the arm 129. A returning spring may also be provided for the universal bar, the spring also aiding in starting the type-barsback. from their printing positions. Spring 120v also affordsv similar aid, and further aid may be derived from the usual cammmg action of the escapement-.wheel 117 upon theusual beveled idogs 118, 119 of the Underwood typewritin machine. The tappets 122v are at di erent heights and of different lengths, to impart substantially uniform movements to the uniiversal bar; and any tappet may be led or 4 type-guide is mounted upon a front horizontal cross-bar 139 which extends beneath the type-guide forks or prongs 99 and is riveted at 140 to the front of said prongs; said crossbar 139 atits ends being bent down to form 'f''diverging supports 141, which extend to the lis fixed upon a transverse horizontal" rock- 156l may be maintained in a midway idle shiftpositionby adjusting the shaft 169 to itsv opposite sides of the machine, each being there securedl by screws 142 tothe main framework 143. The prongs 138 of the ribbon-vibrator device extend up from a vU- shaped operator 144. Said o erator has a shank 145, the bottom-whereo is pivoted at 146 to theforward end of an arm 147, which is pivoted at 148 upon a bracket 149,-that is screwed upon the platen-shift-rail-or frame 1 14 to shift up and down with the platen. The arm 147, together with the ribbon-'vibrator 144, is operated by means of-a Vuniversal bar 150 that extends transversely of the vmachine beneath the key-lever elbows and isv operateduniformly by lugs 151 `depending from the various key-levers. The lugs are of suicient length to afford slight corrective bending, to Secure uniformity inthe-'operation of the universal bar 150. The stroke of the,

towards or from the reader, and, by reason latter continues throughout the key-stroke, so that the vibration of the ribbon is'effected at a relatively slow rate, thus minimizing liability of the ribbon to overthrow, and also easing the key touch. It may be here noted that an-y tappet 122 may be cut off' when it is desired to operatethe -ribbon without feeding, the carriage, at the keystroke,

thus making it unnecessary for the-I employment of special mechanism when it 1s desired to provide the machine with silent :keys

The universal bar 150 extends horizontally across the machine, and has at its ends opposite arms 152 fixed upon a horizontal rockshaft 153. Upon the rock-shaft is provided anv arm 154, to which is connected a returning spring 155, and to which is also connected `an upwardly "and rearwardly extending pull-v link 156. .At its upper end provision is made for connecting said link to an arm 157 which shaft 158, .the -latter mounted in fixed brackets 158a and 158?, Figure 2, and having apend- "ent arm 159, connected by a link 160 te the ribbon-vibrating arm l147jalrea.dy descrlbed,

farms 157'and-165 vwith'their pins are sep- AvSaid link 160 vibrates up anddown idly" at rearwardly, and arm' 154 `is swung v down thereby swinging forwardly the arm 159, -and by means of link 160 the arm 147 isvibrated to lift the ribbon to cover the printing point.

The arm 157 mayV beprovided with an ad,

justable stop 161. The aforesaid long pinion-vibrating arm 157 is provided with operating pin 162, en-

gageable by a rear slot 163 in the upper end of the main'operating link 156.. Upon. therock-shaft 158, to which the. long arm 157 is secured by a set-screw 164, there is also se-l cured a short arinl65, having its operating pin 166, engageable by a forward slot 167 that is also provided in the upper end of link 156. The link may therefore be articulated at will either to the pin 162 or to the pin 166, thus giving either a short stroke or a long stroke to the ribbon-vibrator 155, to bring into'use either one ofthe colorstripes shown up'on the ribbon. The bringing into use of either pin 162 or 166 is effected by swinging the upper end of the link towards or away from the reader at'Figures A11 and 12, this shifting operation being Ieffected by means of the color-shift, key-lever 168 mounted at the usual place-in the front of the typewriting machine. Said lever is mounted upon a rearwardly extending rock-shaft169, suitably supported in the framework at 170 and else-- where, and at its rear end having'a crank a slot 172 in. an

171 constantly engagin ear 173 that'isv bent off om the link 156 at its upper end. As the shaft 169 is dropped by one of its color keys, the crank 171 is swung of its engagement with theslot 17 2, the upper end of the ribbon-operating link 156 is giveni a corresponding colorshift said slot `172 extending longitudinally of'said' link, pref erably parallel therewith, s o that. the link will ride freely upon said crank or pin 171 during the type-key strokes; said crank. 171

110.v and the ear l173 being at an acute angle to being, howeverpar'allel with the shaft 169 "said crank 171, since the ear extends in the direction of the pull ofthe link 156. At its upper end the link 1,56 terminates in a guiding tongue 174, working in a horizontal cross-slot 175 in a guide-bracket 176 that is suitably supported upon the" framework by means of screws 177 The slot 17 5 permits theside-to-'side color-shifting of the link 156,

while guiding it against accidental `forward or backwarddisplacement. 'Y

For stenciling purposes, theactive link midway` or stenciligposition, so that the crank171 occupies a midway-position.v The arated -suiiiciently to admit of the disengage- I pins at the Sametime.

Maasai machine, and it is also desired to increasethe' length of that portion of the ribbon which extends close to the platen at each side of the printing point, so as to give clearance to the type-actions at the sides of the system,

where the types rise near the front of the' platen, as will be understood from .the typepath shown at 73, Figure 8. Accordingly, the ribbon is carried straight along the platen from side to side of the type-linkage system at the upper border thereof, as will be understood from Figure 2. It is, however, desired that the spools remain stationary as usual at the ribbon-vibrating operation,- while at the printing point the ribbon must be vibrated up and down to the usual extent. There arises a difficulty in managing the ribbon between the printing point and the spools, inasmuch as a great length of ribbon extends horizontally along the platen andclose thereto from the opposite sides of the ribbonvibrator 138. The length of ribbon extending obliquely from each spool to the platen is very much shorter than heretofore, and one end of this short length it is desired to vibrate while the other end is stationary, without creasing, fouling or snarling of the ribbon.

To this end, there are provided subsidiary corner-guides 179 at opposite sides of the printing point and spaced therefrom, being situated at the ends of the great length of ribbon 180 which is kept close to the platen; and the ribbon turns corners over these guides 179 and runs obliquely forward to the spools 137. These corner-guides are mounted upon arms 181, which swing up and down at the ribbonvibrations, the extent of vibration of the corner-guides 179 being considerably less than the vibration of the central main ribbonguide 138. The central ribbon-vibrator 138 is preferably itself mounted upon the same arms 181 asA the guides 17 9, so as to vibrate therewith. Hence, while the ribbon is vibrated up and down to a suhcient extent at the printing point, its vibration is made considerablyl less at the corners 179 near the spools 137, so that the ribbon is successfully carried along the platen for quite a distance to points near the spools, without engendering a tendency to snarl or foul the ribbon or strip it down or up from the spools by-reason of the vibration of the' ribbon at the printing strokes. This advantage is gained because said vibration is relatively small at the corners where the ribbon leaves the vibrator, and the corner-guides 179 are relatively close to the pivots 182 of vibrating arms 181, and

move up and down correspondingly less than does the central two-part ribbon-vibrator 138 at the printing point. The operating shank 144 at its upper end is provided with transverse slots 183, engaging operating pins 184 on the inner ends of said ribbon-vibrator levers 181, so as to vibrate the levers and ribbon up and down at the keystrokes. Said pins 184 are provided upon ears 185, which arebent forwardly and upwardly from the inner ends of the levers 181, and may also serve to guide the inner ends of said levers.

There may bevalso provided midway ribbonguiding pins 186 arranged on the levers 181 'between the guides 179 and 138.

One of the arms 152 maybe provided with a spring-pawl 137 to engage a ratchet-wheel 188 on transverse shaft 189, geared to upright spool-shafts 190 to wind the ribbon in the manner usual in the Underwood machine.

Variations may be resorted to within the scope Vof the invention, and portionsfof the improvements may be used without others. Having thus described my invention, T claim:

1. In a front-strike typewiiting machine, the combination with a platen, of a system of type-keys, a system of rearwardly-extending key-levers whereon the keys are mounted,

said key-levers in the form of elbows which at their rear portions turn upwardly and are pivoted at their upper portions, a system of pivoted sub-levers which extend up vand down l and against which the upwardly-extending arms'of the key-levers swing edgewise, and a system of type-linkages to which the sublevers are connected by means of links extending forwardly from the sub-levers to the type-linkages, the vertical arms of the keylevers being arranged to roll upon the sublevers, each type-linkage including a rear drive-link connected by an adjustable conneotion to its sub-lever, and also including a forward upstanding guide-link, andy also including a type-carrier pivoted upon said links and normally in folded cumbent position. i 1

'2. In' a front-strike typewriting machine, the combination with a platen, of a system of type-keys, a system (tfirearwardly-extendingA key-levers whereon the keys are mounted, said key-levers in the form of elbows which at their rear portions turn upwardly and are pivoted at their upper portions, a system of pivoted sub-levers which extend up and down and against which the upwardly-ex-V tending arms of the key-levers swing edgewise, a system of type-linkages to which the sub-levers are connected by means of links extending forwardly from the sub-levers to the type-linkages, said key-levers working in substantially vertical planes and pivoted at about-the level of the keys, said rear keylever-arms forming a horizontal transverse row and having up and down treads, and a levers fanning out from side to side and at their lower ends about equal in 4width to the key-lever system and working in radial planes, said sub-levers extending upwardly in rearof and abbve the row of key-leverarms and being pivotally connected to the' type-linkagesat points above the key-levers, said upright arms of the key-levers forming 'treads or rocker-portions to roll down upon the sub-levers, said rocker-portions bent radially to correspond with the spreading arrangement of the sub-levers, said key-levers gui-ded laterally at their pivots, at their elbows, and at their key-ends.

3. In a front-strike typewriting machine, the combination with a platen, of a system of type-keys, a system of rearwardly-extending key-levers whereon the keys aremounted, said key-levers in the form of bell-cranks which at their rear portions turn upwardly and are pivoted at their upper portions, a system of pivoted sub-levers which ,extend up and down and against which the upwardly-extending arms of vthe key-levers swing edgewise, a system of typeflinkages to which the sub-levers are connected by means of links extending forwardly from the sub-levers to the type-linkages, the vertical arms of the key-levers being arranged to roll upon the sub-levers, each type-linkage including a rear drive-link connected Ito its sub-lever, and also including a forward upstanding guide-link, and also including ay type-carrier pivoted upon said links and normally in folded cumbent position, means for guiding the drive-links, a slotted radial guide for the type-linkages, each type-carrier havL ing an upwardly-projecting ear at the articulation thereof to its guide-link, to work in said slotted radial guide, the latter overlying the system of guide-links, the links and typecarriers being constantly guided throughout their printing strokes, `and a center guide at' the printing point common to all'of the type-carriers, a curved dust-shield being provided over the articulations of the drivelinks to their supports, the drive-links being formed with clearances for said dust-shield.

4. In a front-strike typewriting machine, the combination with a platen, of al system of type-keys, a system of rearwardly-extending key-levers whereon the keys are mounted, said key-levers in the form of bell-cranks which at their rear portions turn upwardly and are pivoted at theirlupper portions, a syswise, a system of'type-linkages to which the sub-levers are connected by means of links extending forwardly 'from the sub-levers to the type-linkages, the vertical arms of the .key-levers being arran ed'to roll upon the sub-levers, each type-lin age including a rear drive-link connected to its sub-lever, and also including a forward upstanding guide-link, and also' including a type-carrier pivoted upon said links and normally in folded cumbent position, returning springs connected to saidY key-levers and extending forwardly and downwardly from the, pivotal portions thereof, and returning springs connected to said type-linkages and radiating forwardly'and downwardly from said drive-links from points near the fulcrumthereof, the leverage of the returning spring upon the Adrive-link substantially decreasing during the printing stroke.

5. Machine constructed according to claim 2, the sub-leversbeing substantially less convergent than the type-bars, and at their upper ends standing about directly in rear of and level with the points of engagement of the pull-links with the drive-links.

6. In combination, a system of rearwardly-striking type-linkages, a system of keys,

a system of connections from the keys to the type-linkages affording a maxlmum leveragev of the keys upon the type-linkages at the beginning of the key-strokes and decreasing Y' leverage during the printing strokes, each type-linkage including a rear link, a front link pivoted upon the framework, and a carrier normally folded and pivoted upon the free ends of said links for an upward un.

f olding motion and a rearward floating motion to the platen, said type-carrier having a 1 type at its upper end, the pivot of the forj llO ward link being at a point substantially higher than the pivot of the rear link and' mov-y ing in a rearward and downward path at the conclusion of the printing stroke, thereby rotatl'ing reversely the type-carrier upon its point of pivoting to the rear link and conse-` quently effecting a deceleration of the type as it approaches the platen to reduce the noise of impact and give strong leverage of the keyaction upon the type to press the same firmly upon the platen; a line from the fulcrum of the forward link to the printing point nearly passing through the forward pivot of the type-carrier at the moment of printing, said forward link being substantially shorter and pivoted higher than said rear link and normally extending upwardly and rearwardly from its pivot, and the rear link normally extending toward the pivot vof the forward link,

the weight of the type-carrier lying mainly in line with its two pivots, and said type-caraveaeei rier and said rear link being weighted near their articulations to each other to increase the shock of impact of the type against the platen, and render the linkage enicient toprint at a decelerated speed of the striking type, the length of th-e type-carrier between its pivots being approximately equal lto the length of the forward link and less than the length of the rear link, and key-controlled means to operate said rear link.

7. In a front-strike typewriting'machine, the combination with a platen, of a-system of type-keys, a system of rearwardly-extending key-levers whereon the k-eys are mounted, said key-levers in the form of bell-cranks which at their rear portions turn upwardly and are pivoted at their upper portions, a system of pivoted sub-levers which extend up and down and against which the upwardlyextending arms of the key-levers swing edgewise, and a syst-em of type-linkages to which the sub-leversare connected by means of links extending forwardly from the sub-levers to the type-linkages, the vertical arms of the key-levers being' arranged to roll upon lthe sub-levers, cach type-linkage including a rear drive-link connected to its sub-lever, and also including a forward upstanding guide-link, and also including a type-carrier pivoted upon said links and normally in folded cumbent position, the point ofcontact between the forward upstanding key-lever arm and the sub-lever being normally close to the keylever pivot, and the contact between the keylever and the sub-lever remaining near said pivot throughout a substantial portion of the' key depression, and being again gradually shifted down to a point of nearest approach to the pivoted sub-lever, which point is reached when the type-linkage is substan- A tially unfolded and the type-carrier begins its relatively slow rearward floating movement, the decrease of the leverage bemg reduced but little, if any, during the remainder of the floating stroke of the type-carrier, to' avoid unnecessary speeding of the type at the conclusion of the printing stroke, the weight .of the linkage tending` to absorb the momentum of the operators hand, the forward or guide link forming` an obtuse angle with the type-carrier at the moment of printing.A

8. In a front-strike typewriting machine, the combination with a platen and a systemof normally folded front-strike type-linkages,

each including a rear drive-link, a forwardguide-link and a type-float, of a system of key-levers in the form of bell-cranks, and a system of upright sub-levers connected to said type-linkages and saidkey-levers, said bell'- cranks having upstanding arms constructed to roll upon said upright sub-levers toeifect reduction of the leverage of the keys throughout the printing strokes; said sub-levers being of the third order and pivoted at their lower ends below the key-lever elbows, and at their fill;

upper ends having links extending forwardly to the type-linkages; the downward movement of each key effecting a rearward movev ment of its sub-lever, the latter standing-edge to edge in line with the upstanding arm of the key-lever in rear thereof.

9. Machine constructed according to claim 8, the type-linkage system being mounted between the keys and the sub-lever system, and

the systemv of type-floats lying between the.

system of sull-levers and the system of guidelinks; said sub-levers arranged in converging planes and the upstanding arms of the keylevers being correspondingly arranged for rolling upon the sub-levers, said key-levers working in vertical planes, and thesystem of upstanding arms at their upper ends being a type-carrier pivoted upon the other members of the linkage,l and springs to take up the play at articulations of the type-carrier to its supports in a manner to avoid knocking of said articulations as the result of the impact of the types against the platen.

ll. In a typewriting machine, the combii nation with a platen and a 'system of typelinkages including links and type-carriers" mounted thereon, of keys for operating said type-linkages,reach of said linkages including a type-carrier pivoted uponthe other members of the linkage, and springs to take up the play at articulations of the type-carrier to its supports in a manner to avoid knocking of said articulations as the result of the imy pact of 'the types against the platen, each spring connected to pull the type-carrier against its supporting link and also to pull said link against the pivot upon which it roc is. l

y 12. ln a typewriting machine, the combination with a platenand a system of typef linkages including'links and type-carriers mounted thereon, of keys foroperating said type-linkages, each of said linkages including f a type-carrier pivoted upon the other members of the linkage, and springsto take up the play at articulations of the type-carrier to its supports in a manner to avoid-knocking of said articulations as the result of the impact of the types against the platen, each system of type-linkages including a forward and rear link, and the type-carrier pivoted upon said links, and each spring being connected to the forward end of the type-carrier to pull the same down together with the forward link, the spring passing about through the axis of the pivot and extending substantially towards the pivot of the guide-link upon the framework of the machine.

13. In a typewriting machine, the lcombi-v Y nation with a lplaten and a system of keydriven type-linkages, each including a typecarrier and links upon which it is mounted, of springs opposing the tendency of llinkage' joints to knock byreason of the impacts of the types against the platen.

' 14. In a ront-strike typewriting machine,

A' p the combination with a, platen, of a system Yof type-linkages, each including a rear link anda front link pivoted upon the framework and a triangular type-carrier'norm'ally folded and pivoted onthe free ends of said links for an upward unfolding motion and a rearwardfloating motion to the platen, each type-carrier having a type at its upper end and having its sides about equal in length, the typecarriers compactly occupying a position in rear of the 4forward links and with their rear type-ends directly overlying the pivots Y of the rear links,A the' length of the rear link normally spaced considerably back of the pivot 69, the forward link being substantially shorter than the rear link and also standing at a substantially higher elevation, so that in i printing position the direction of the lower side of the type-carrier is obliquely downward and backward from the front link to the rear link, said front link in printing position extending obliquely upward and backward, and the rear link in printing position standing about upright, whereby the speed of the type itself when close to the platen is greatly decelerated, relatively to the remainder of the linkage, to minimize lt-he nois'eof impact'of the type on the platen, the type-carrier turning relatively towards the left about pivot 71 as the lattertravels rearwardly, the type being Vgiven an independent movement of retardation about said traveling pivot 71.

15. In combination, a system of rearwardly-striking type-linkages, a system of keys, a systemof connections from the keys to the type-linkages, each type-linkage including a rear drive-link, a front guide-link, and a type-carrier normally folded down and pivoted upon the free ends of said links for an upward unfolding motion and a rearward floating motion to the platen, saidlinks being pivoted upon a system of individual radial plates or hangers, each inclusive of a plate, with forward and rear arms branching from said plate, the system of plates being fixed in a'system of slots formed in a segment,

said slots radiating downwardly and forwardly from the printing point, bolts rigidly holding the plates in the slots, each bolt having a head catching over adjoining hangers,

' a common segment or fastening plate sur- "mountingthe plates and held down thereony by the headsof said bolts, said bolts extending through holes formed in the segment, said bolts being thinned or having flattened sides to clear the hanger-platesv and to permit the endwise-insertion or withdrawal of the plates while the loosened bolts remain in place, and

nuts to draw said bolts tight upon the fastening plate, the latter engaging the edgesof the hangers which protrude from the segment, each hanger-plate having a' shouldered portion which fits upon the inished forward face of the segment, the. hanger having a shoulder formed thereon above the inner or iinished face of the segment, the rear branch of each type-hanger having a guiding horn A for the drive-link.

16. Machine constructed according `to claim 14, in which each forward guide-link is folded lengthwise and also given a U-shape for the purpose set forth, the upper end of vlthe link formed of opposite ears to bestride a type-carrier pivot, said pivot having oppositely projecting. central stud-portions extending through said opposite ears and headed thereover, a guiding nib extending upl wardly from the forward hub-portion of the type-carrier, and a-segmental general guide overlying said forward links, said guide radially slotted on its under side, said vnibs working in said radial slots, and guiding and supporting the type-carrier in its movement towards the central fixed type-guide, each guide-link having at its bottom corresponding ears embracing the upper end of the hanger-arm and similarly pivoted thereto.

17. The combination with a platen, of a type-linkage below the platen and including a rear drive-link which is normally cumbent, a forwardly-extending link, and a type-carrier pivoted upon said links and normally folded down, whereby at the operation of said drive-link the linkage unfolds rapidly until the type-carrier is fully elevated and floats slowly rearwardly upon the links against the platen, an operating lever connected to said drive-link,'and a key-lever, each of said levers extending from its fulcrum towards the fulcrum of the other lever, said key-lever having a rolling engagement with said operating lever, including an edge which has a flattened curve terminating at its ends in dwell-portions near the fulcrums of saidlevers, the first dwell-portion affording a great leverage to the key, to slow down the early portion of the unfolding movement of the type-linkage, and the other dwell-portion y giving a much-reduced leverage of the key upon the linkage, to speed the linkage in its rearwardly-floating movement to strike the type against the platen.

18. In astandard -front-strike typewriting machine modified substantially as set forth,

the combination with a system of type-linkages and a system of key-bearing bell-cranks to Operate said linkages, upwardly extending arms operated by said bell-cranks and having rear tappets thereon, of a universal bar in the form of a bail operated by said tappets, an arm connected to said universal bar, a thrust-link extendingupwardly from said arm, and a carriage-feeding dog-rocker havinfT an arm engaged by the upper end of upwardly and are pivoted at their upper portions, a system of pivoted sub-levers which extend up and down and against which the upwardly-extending arms of the key-levers swing edgewise, and a system of type-linkages to which the sub-levers are connected by means of links extending forwardly from the upper ends of the sub-levers to the typelinkages, the upwardly-extending arms of the key-levers being arranged to roll downwardlas ly upon the sub-levers, each type-linkage including a rear drive-link connected to its sublever, and also including a forward upstanding guide-link, and also including. a typecarrier pivoted upon said links and normally in folded cumbent position, said sub-levers being of the third order and fulcrumed at their lower ends, and being in rear of the key-levers, and said linkages being in rear of the keys and above the rearwardly-extending bodies of the key-levers and in front of the upwardly-extending arms of thekey-levers.

20. ln a front-strike typewriting machine` the combination with a platen, of a system of type-keys, a system of key-levers having bodies extending rearwardly from the keys, said key-levers in the form of elbows whose portions form arms which extend upwardly and are pivoted st their upper endwhich extend up and down and against which the upwardly-extending arms of the keylevers swing edgewise, and an arcuate system of radially arranged'type-linkages to which the sub-levers are connected, said key-levers working in substantially vertical planes, said rear key-lever-arms forming a transverse row and lhaving up-and-down treads, said sublevers being pivoted at their lower ends, said sub-levers being of varied lengths to accommodate the arcuate 'arrangement ofthe system of type-linkages, and said typelinkages being below the front of the platen and above thekey-lever bodies and forward of the npa f-syst'em. of pivoted sub-levers.

wardly-extending arms, the system of typelinkages being narrower than the system of key-levers, the width of the system of' sublevers at the top being about equal to the width of the system of type-linkages, said system of sub-levers ,fanning out from side to side and at their lower ends about equal in width` to the key-lever system, said keylevers having rocker-portions bent radially to correspondwith the spreading arrangement of the sub-levers.

21. In a front-strike typewriting machine, the combination with a platen, of a system of type-keys. a system of key-levers, a s .stem of pivoted sub-levers, a system of typeinkages to which the sub-levers are connected, each type-linkage including a rear drive-link connected to its sub-lever, and also including a forward upstanding guide-link, and also including -a 'type-carrier pivoted upon said links and normally in folded cumbent position, a means for guiding the drive-links between their ends, a slotted radial guide for the type-linkages, each type-carrier laterally guided thereby at the region of its articulation to its guide-link, the radial guide overlying the system. of guide-links, the links and type-carriers being constantly guided throughout their printing strokes, and a center guide at the printing point common to all of the type-carriers. c

22. ln a front-strike typewriting'machine, the combination with a platen, of a systemv of type-keys, a system of key-levers having bodies extending rearwardly from the keys, said key-levers in the form of elbows whose portions form arms. which extend upwardly. and are pivoted at their upper end-portions,

a system 'of pivoted sub-levers which extend up and down and against which the upwardly-extend'ing arms of the key-levers swing edgewis'e, and an arcuate system of radially arranged' type-linkages to which the sublevers are connected, said'key-levers working in substantially4 vertical planes, said rear keylever-arms formi-ng a transverse row and having up-and-down treads, said sub-levers being pivoted at their lower ends, said sub- A levers being of varied lengths to accommodate the arcuate arrangement of the system of type-linkages, and said type-linkages being below the front of the platen and above the key-lever bodies and forward of the upwardly-extending arms,'returning springs being connected to said key-levers, and returning springs being also `connected to said typelinkages and radiating forwardly and downwardly from said drive-links from points near the fulcrums'thereof.

23. ln a front-strike typewriting machine, the combination with a platen, of a system of type-keys,a system of rearwardly-extending key-levers whereon the keys are mounted, said key-levers in the form of elbows which at their rear portions turn upwardly and are pivoted at their upper portions, a system ofl pivoted sub-levers which extend up and down and against which the upwardly-extending arms of the key-levers swing'edgewise, and an arcuate system of type-linkages to which the sub-levers are connected by means of links extending forwardly from the sub-levers toV the type-linkages, said key-levers working in substantially vertical planes and pivoted at about the level of the keys, said rear keylever-arms having up-and-down treads, saidvabove the row of key-lever-arms and being pivotally connected tothe type-linkages at points above the key-levers, sai upright arms of the key-levers forming treads of rockerportions to roll down upon the sub-levers, the

. sub-levers at their upper ends standing about directly in rear'of and level with the points of engagement of the pull-links with the drive-links. j 24. In combination, a system ofrearwardly-striking type-linkages, a system of keys, a system of connections from the keys `to the type-linkages constructed to aHord ay maximum leverage of the keys upon the type-link` ages at the beginning of the key-strokes and decreasing leverage throughout the printing strokes, each type-linkage' including a cumbent rear link, an upstanding front link, both links pivotedupon the framework, and a carrier normally folded and pivoted upon the free 'ends of said links for an upward unfolding motion` and a rearward floating motion to the platen, said type-carrier having a type at its upper end, the upper pivot of the forward link being at a point substantially higher than 'the pivot of the free end of the-rear link and moving in a rearward and downward path at the conclusion of the printing stroke, thereby rotating reversely the type-carrier Y upon its point of pivoting to the rear link and effective to decelerate the type as it approaches closely to the platen to reduce the noise of impact and give strong leverage of the keyaction upon the type to press the same firmly upon the laten, said upstanding link being fulcrumed) at a point substantially higher than the fulcrum of the rear link, and the free end of the rear link being normally nearly fin line with the fulcrums of both links.

` 25. In' combination, a system of rearwardly-striking typelinkage's,'a systeml ofkeys,

a system of connections from the keys-to the .i

type-linkagesl affording a maximum leverage of the keys upon the type-linkages at the beginning of the key-strokes and enormously decreasing j leverage during, the printing strokes, each type-'linkage including a rear drive-luik, a front guide-link pivoted Iupon lthe framework, and a carrier normally fold` ed and pivoted upon the free/ends of said links for an upward unfoldingmotion followed by a rearward floating motion to the platen, said type-carrier having a type at its upper end, the free pivot ofthe\guide-link being at a point substantially higher than the free pivot-of the drive-link and moving in a rearward and downward path at the conclu- 'sion of theprinting stroke, and effective to rotate' reversely the type-carrier upon its point of pivoting to the drive-link and decelerate-the type as it approaches the platen, a linefrom the fulcrm of the forward link f to the' printing point passing immediately in the rear link normally extending toward the pivot of the forward link.

26. Machine constructed in accordance with claim 25, in-which the weight of the type-carrier lies mainly. in line with its two pivots, said type-carrier and said rear link be- I ing weightednear their articulations to each other to increase the shock of impact of the typeagainst the platen, and render the linkage eiiicient to print at a decelerated speed of the striking type. 27. In a front-strike typewriting machine, the combination with a platen, of a system of type-keys, al system of rearwardly-extending key-levers whereon the keys are mounted, said key-levers inthe form of elbows which at their rear portions turn upwardly and are pivoted at their upper portions, a system of pivoted sub-levers which extend and down and against which the upwardlyextending arms of the key-levers swing rearwardly edgewise, and a system of type-linkages to which the sub-levers are connected, the vertical arms of the key-levers being arranged to roll upon flattened curves `1 Amally in folded cumbent position, a dwell being provided at the point of contact between the forward upstanding key-leverarm and the sub-lever, said dwell being close to the key-lever-pivot, and the contact between the key-lever and the sub-lever remaining upon said dwell and near ,said pivot throughout a substantial portion of the key depression, the flattened curve shifting thepoint of contact rapidly to a lower dwell provided at the point of nearest approach to the pivoted sub-lever, which lower dwell'is reached when the typelinkage ,is substantially" unfolded and the type-carrier begins its relatively slow rearward ioating movement, the decrease of the

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