US2336976A - Typewriting machine - Google Patents

Description

Dec. 14, 1943. J. P. BARKDOLL TYPEWRITING MACHINE Filed May 23, 1941 2 Sheets-Sheet l a M x m ma m 50 Jim A'r'r URNEY Dec. 14, 1943. J. P. BARKDOLL TYPEWRITING MACHI-NE Filed May 25, 1941 2 Sheets-Sixes: 2

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A TIJRNEY' Patented Dec. 14, 1943 TYPEWRITING MACHINE Joseph P. Barkdoll, Groton, N. Y., assignor to L Smith & Corona Typewriters, Inc, Syracuse, N. Y., a corporation of New York Application May 23, 1941, Serial No. 394,899

18 Claims.

The invention relates to improvements in typewriting machines and. more particularly, to improvements in type actions for such machines.

The primary purpose of the invention is to provide an efficient type action by means of which imprints of good quality may be made easily and rapidly and substantially without noise.

Another purpose of the invention is to provide a type action including means for controlling the final portion of the impression effecting travel of a rapidly impelled type carrier by snubbing said carrier as it nears impression effecting position and then forcing the carrier to impression effecting position by the snubbing means.

Another purpose of the invention is the provision of a key actuated toggle means for impelling a type rapidly and easily to a point adjacent the platen of the machine and there checking the movement of the type, and the provision of an independent toggle means, actuated by said type movement, first to store energy in said means, then to snub the type at (or substantially at) the time the key actuated toggle means checks the type, and finally to expend its stored energy in a toggle thrust drive of the type to the platen.

A further purpose of the invention is to provide an efiicient, inexpensive and compact silently printing type action especially suitable for use in a small and compact portable typcwriting machine.

To the above and other ends which will hereinafter appear, the invention consists in the features of construction, arrangements of parts and combinations of devices set forth in the fol lowing description and particularly pointed out in the appended claims.

In the accompanying drawings illustrating the preferred embodiment of the invention:

Figure 1 is a fragmentary vertical longitudinal sectional view taken medially of the machine and illustrating the central one of the type actions thereof with the parts in normal idle position.

Figure 2 is a similar sectional View illustrating the parts as they appear at the end of the down stroke of the character key.

Figure 3 is a similar sectional view showing the position of the parts at the end of the printing advance of the type.

Figure 4 is a detail sectional view on line 44, Figure 2.

The machine illustrated includes a suitable supporting framework for supporting, among other parts thereof, the usual traveling platen carriage H and a system of the improved type actions, the usual roller platen l2 being journaled in the carriage. A description of a single one of the improved type actions will suffice for'an understanding of the invention by those skilled in the art.

The type carrier of the improved type action is a type bar of bellcrank form, having a type head carrying arm l3 anda shorter arm it. The type bar is pivoted at the junction of its arms iii-Hi at i5 to part of the supporting framework to swing rearwardly about a horizontal axis to the platen from a normal idle or rest position. At its free" upper end arm 83 has fixed thereto the type carrying head it which is preferably provided with two types ll, one an upper case type and the other a lower case type. The type carrying head i6 has a portion thereof normally seated against a type bar rest or pad 18 held to the supporting framework of the ma.-

chine.

The free forward end of arm it is connected by a horizontal pivot E9 to one end of a pull link 20, the other end of which link is connected by a horizontal pivot 21 to the rear arm of a bellcrank lever 22. Lever 22 is pivoted on the supporting framework on a horizontal pivot 23. An arm 24 is pivoted at its rear end on' the supporting framework on ahorizontal pivot 25 located below pivot 23; The forward ends of lever 22 and arm 25 are connected by horizontal pivots 2t and 27 to an arm 28 which is formed at its lower end with an integral forwardly and upwardly extending key carrying stem or arm 29'to' which is fixed a suitable character key 35. A type action return spring M is connected at its opposite ends to link 2% and the supporting framework.

The pivot point iii of type bar iii-l4 is below and rearward of the point ofcontact of head It with rest I 8, and is below and forward of the printing point P, so that arm l3 extends generally upward and forward in the idleor rest position of the type bar and upwardand rearward in the printing position of the type bar. Arm I 4 preferably extends forward and downward from pivot I 5 in the rest position of the type bar, and said arm and the link 23' form atoggle which is downwardly collapsed or partly folded in the rest position of the type bar and is operable by lever 22, upon key depression, to swing arm l3 toward the platen. Depression of key 30 rocks lever 22 in a direction to straightentoggle I i-26, and the maximum throw of the type bar is such that said toggle willbecome fully straightened shortly before the type bar completes its printing stroke. Toggle I l-20 is thus at, the instant toggle I420 is straightened, and r to complete thereafter the printing stroke of the type bar in such manner as to effect a quietland powerful impression of the type by toggle pressure from power stored in 1 said secondto ggle' device during the previous and major portion of the printing stroke of the type bar Said second toggle device comprises generallythe toggle links 32 and 33, and hinge means connecting said links and providing successively ef-' fective hinge connections between said links. Link 32 is pivotally anchored to arm l3 by a horizontal pivot 34, and link 33 is pivotally anchored to thesupporting framework by a horizontal pivot 35. It will be seen, therefore, that this second toggle device is actuated exclusively from type driving arm l3, since it has no driving connection other than said arm.

This second toggle device functions, on the printing stroke of the type bar, to store energy, to snub the type bar, and finally to expend its stored energy to complete the printing stroke of the type bar by toggle pressure. To best accomplish these ends, in the preferred embodiment,

link 32 is preferably made as light as is conveniently possible, and link 33 is preferably made as heavy as is conveniently possible. This is attained preferably by perforatinglink 32 as at 32 to reduce its weight, and by augmenting the weight of link 33 (as by providing itwith, an integral weighting portion 33*), so that link 33 may constitute the primary momentum accumulating element of the second toggle device.

As will be apparent, this second toggle device is energized'exclusively by arm [3 and functions,

on the printing movement of a type, first to check. said type movement as the type approaches the impression point and thereafter to complete the printing movement of the type by powerfulto le pressure, the links of said toggle being so consuccessively effective hinge nected as to have two axes one of which moves into a straight line connecting the toggle anchorages to cause the toggle to exert a pull checking effect on the ad-' vancing type and the other one of which'advances toward said line to further expand the toggle to complete the printing movement of the type by toggle pressure.

While, preferably, the maximum type travel is not such as to instant, although preferably the two checking efforts of the two toggle devices occur, (as shown) at the samepoint inth travelof the type toward e a n- 4: rim

bring the secondly effective one I of said hinge axes into line with the toggle an- A pintle pin 36 extends horizontally through link 32 at that end of the link which is opposite the end anchored to arm l3. Pin 36 is fixed to link 32 and its opposite ends extend through and are slidable in slots 31 in a pair of brackets 33. Brackets 38 are rigidly affixed to opposite side faces of link 33 and overlap the side faces of the pintle carrying end of link 32. Slots 31 are directly opposed and extend generally longitudinally of link 33. A short link 39 is pivoted at one end thereof on pintle pin 36 between one of the brackets 38 and the adjacent side face of link 32, and said link 33 has its opposite end connected to link 33 by a contractile coil spring Iii) ' 40 'Spring' lll and link 39 extend generally longitudinally of link 33, said spring 40 being an-- chored to link 33 about midway between the ends of the latter link. Link 39 and spring 40 normally yieldingly hold the pintle 36 at that end of each of the slots 3'! which is nearest the pivotal anchorage 35 of link33. Links 32 and 33 have end faces 4! and 42 respectively adapted to be brought into engagement and to thereafter rock one on the other, as more fully hereinafter explained.

Links 32. and 33 and the hinge means connecting the same form a toggle device which is collapsed or folded downward in the rest position of the type bar with link 33 seated against a suitable rest or pad 53 held to the supporting framework. In the rest position of the type bar, in the construction shown, this toggle device is fully collapsed with pivots 35, 34, 36 and i5 located in the recited order in a straight line which extends nearly'parallel to arm 13. In this position of the toggle device the end faces ii and 42 of links 32 and 33 lie in a common plane passing through the axis of pintle 33 but are located at opposite sides of said pintle, said plane being perpendicular to said last mentioned straight line. r

'- 45 in, the supporting framework. Lever 22 adjacent its pivot 23 is preferably guided in a suitable slot K3 in the supporting framework, and arm adjacent its pivot 25 is preferably guided in a suitable slot ll in the supporting framework.

To render the key touch as easy and light as possible, andto facilitate rapid operation, the parts in the key operated type action shown are arranged so that, in the rest position of the type bar, a straight line connecting pivots i5 and i9 makes a right angle with a straight line connecting pivots i9 and 2 i. Preferably also in the rest position of. the type bar the rearwardly extending ,arm. of lever 22 extends upward and rearward from pivot 23 at the same angle to the horizontal thatarm It extends downward and forward from pivot l5.

Preferably also, as shown, in the preferred construction illustrated, the forwardly extending arm of lever 22 is shorter vthanarrn 23, and, in the rest position of the type bar, extends upward and forward at a greater angle tothehorizontal than arm 2 so that, in the rest, position of the type bar, the arm 28extends forward and downward from pivot 23 to pivot 21.1.

The relative positions of the platen i2 and the type action in the construction shown are such that the printing point P is somewhat above the horizontal lane of the, platen axis for improved visibility, and, arealso such that the lowermost one of the two types H on the type bar will normally coact with the platen to effect an imprint, said lowermost type being preferably a lower case type and the other type an upper case type. Suitable case shift mechanism may be provided to render the uppermost one of the two types effective to print.

The operation of the type action is as follows:

Depression of the character key 3% will cause the lever 22 to rock until toggle l t-2Q becomes fully extended or straightened. Complete straightening of toggle li2@ prevents further downward motion of key 30, and also tends to check the printing stroke of arm l3, these ends being accomplished before arm is completes its printing stroke and preferably before the effective type contacts the paper backed by platen iii. A desirable point for occurrence of complete straightening of toggle ii2il is one at which the effective type is spaced about .200 inch from the printing point P on the platen.

During straightening of toggle i l-48, and by reason thereof, arm [3 has imparted thereto an accelerated movement about pivot l5, said arm swinging during this period from rest position toward the platen through the major portion of the printing stroke of the arm. This movement of arm it unfolds the toggle device 52-33 anchored to the free upper end of said arm, the links 32 and 33 of said toggle device unfolding about the axis of pintle 36 with said pintle held at the forward ends of slots 31 until said pintle reaches a straight line passing through the link anchorage pivots 3t and 35 to effect a preliminary straightening of the toggle device.

This preliminary straightening i toggle device S2-33 occurs before arm i3 completes its printing stroke and preferably, as shown, occurs coincidentally with the straightening of toggle l t-2t. The preliminary straightening of toggle device 32-33 causes said device to exert a snubbing effort on the rearwardly swinging arm is, supplementing the checking effort exerted by toggle I' l-20.

In moving from rest position, arm 53 imparts an accelerated motion to the momentum accumulating or energy storing link 33 of the toggle device 3233 with the result that, immediately following the preliminary full straightenin of toggle device 32-453, the end faces ll- 32 of links 32ii3 (brought into contact by said preliminary straightening) are caused to rock on each other by stored energy in link 33.

The toggle 32-33 which has at this time been preliminarily straightened is thus automatically converted into a non-straightened toggle which may be further extended under the impetus afforded by stored energy in its link 33 to complete the printing stroke of arm l3 and the impression of the effective type by toggle pressure. The extent of the final portion of the printing stroke imparted by the secondary unfolding of the toggle device 32-33 is small and will cause a slight upward breaking of toggle i l2fi.

Preferably the maximum throw of arm i3 is such that, as shown, the secondary unfolding of toggle device 32-33 does not result in a complete secondary straightening of said toggle device, although it will be obvious that the parts could be so proportioned as to permit complete secondary straightening if desired.

Upon full impression of the efiective type quick initial retraction of arm i3 is effected under the influence of spring 49, weighted link 33 and spring 3!, the parts being ultimately restored to starting position by spring 3! and weighted link 33. The final return movement of arm i3 and of link 33 is a decelerated one.

When the end faces ii-12 of links 3233 begin to rock on each other near the end of the printing stroke of the type bar the pintle 35 moves rearward toward the rear ends of slots 31, as shown in Figure 3. Preferably these slots 3? are slightly arcuate, being curved about the fulcruming point of said faces ii-52, although this is not essential.

Link 32 is preferably made as light as is conveniently possible to reduce thereby its energy storing capacity. To this end said link may be provided with perforations 32 Return or upward movement of key 33 is arrested by engagement of type head it with rest 58 and by engagement of link 33 with rest is. The return spring 3! is preferably so anchored to link 28 and to the parts supporting framework of the machine as to extend downwardly and forwardly from link 29 to said framework in the normal idle condition of the type action at approximately the angle shown, whereby, during the initial portion of the printing stroke of the type bar, said spring swings about its framework anchorage substantially without increase of the tension of the spring and said spring is thereafter abruptly stressed. This arrangement increases the initial lightness of key touch.

What I claim is:

1. In a typewriting machine, a silently printing type action comprising a type, an oppositely movable element connected with the type to advance the type positively to an impression limit and restore the type positively to a normal idle position, means for initiating a type advancing movement of said element, a pair of rigid link elements pivotally anchored one to said oppositely movable element and the other to the supporting framework of the machine, and means jointing said rigid link elements to form, together with said elements, as the type reaches a position close to its printing limit during type advancing movement of the oppositely movable element, both a tautened elastically extensible snubbing connection between the oppositely movable element and the machine framework and also an expansi'cle pressure toggle connection between said oppositely movable element and said framework for elastically extending said snubbing connection and pressing said element to complete the movement of the type to its impression limit, at least one of said pair of jointed link elements being suiliciently heavy for acquiring energy for expansion of said toggle connection.

2. A silently printing type action for a typewriting machine comprising a type, an element connected with the type and pivotally mounted for opposite swinging movements to advance the type positively to an impression limit and return the type positively to a normal idle position, a rigid momentum accumulator pivoted to swing about an axis parallel to and fixedly spaced from the axis of said element, a rigid link pivotally anchored to said element to swing about an axis parallel to and fixedly spaced from the axis of said element, and hinge means connecting said link and accumulator for relative turning movement therebetween about first one and then the other of two parallel axes which are fixedly spaced from and parallel to the pivotal axis of the accumulator and travel one be hin'd'the other about the pivotal axis of the accumulator during type advancing swinging movement of said element to bring the first effective one of said hinge axes, into a straight line connecting the pivotal anchorages of the link and accumulator as the type nears its im' pression limit, and means for initiating a type advancing movement of said element.

3. In a typewriting machine, a silently printing type action comprising a type, an oppositely movable element connected with the type to advance the type positively to an impression limit and restore the type positively to a normal idle position, means for initiating a type advancing movement of said element, a rigid momentum accumulator pivotally anchored to the supporting framework of the machine and provided with a slot having one end thereof nearer than the other to the pivotal axis of said accumulator, a rigid link pivotally anchored to said element to swing about an axis parallel to that of the accumulator, a hinge pintle fixed to said link and engaged in said slot, resilient means normally urging said pinto the end of said slot located nearest the pivotal axis of the accumulator, the link and accumulator forming the links of a toggle device which is collapsed in the idle position of the type and is expansible by type advancing movement of said element with the pin held at said nearest end of said slot until said pin reaches a straight line connecting the anchorages of the link and accumulator, said link and accumulator having portions normally located at opposite sides of said slot and engageable, as said pin reaches said straight line, to cause said link and accumulator to fulcrum on each other at one side of the slot to additionally expand said toggle device to complete the type advancing movement of said element by toggle pressure through energy stored in the accumulater.

4. In a typewriting machine having a framework, a silently printing type action comprising a type, a type driving element, and a momentum accumulating toggle device comprising two links pivotally anchored respectively to said element and the framework of the machine, and hinge means jointing said links and including'means providing successively effective pivotal axes about which said links are unfoldable during driving of the type in type impressing direction by said driving element, one of said pivotal axes being movable across a straight line passing through the link anchorages during printing and return movements of the type.

- 5. In a typewriting machine, atype actioncom prising a type, a type driver, and a toggle having two links and hinge means connecting the links for unfolding thereof about first one and then the other of two different hinge axes, one link of said toggle being anchored to the driver and the other to the supporting framework of the machine for an initial full straightening of the toggle by unfolding of the links about the first one of said hinge axes by the driver as the latter moves in type impressing direction and prior to type impression, said toggle including means to store energy in the toggle during said initial full straightening of the toggle and thereafter to exert a second toggle straightening effort on the toggle to cause saidlinks to unfold about the second one of said hinge axes to finish the type impressing movement of the driver,

6. In a typewriting machine, the combination of a Work backing platen, a type bar'pivoted to swing toward and from the platen and carrying adjacent one end thereof a type coactive with the platen, a toggle having one link thereof pivotally anchored to the supporting framework of said machine and the other link thereof pivotally anchored to said type bar adjacent the type carrying end of said type bar, said toggle being folded in the normal retracted position of the type bar and having hinge means affording two parallel axes about first one and then the other of which the toggle links are unfoldable during the printing stroke of the type bar, at least one of which two parallel hinge axes is carried before type impression, across a straight line passing through the pivotal anchoring axes of the toggle links, and means for initiating a type impressing stroke of the type bar.

'7. In a typewriting machine, a type action comprising a type, a pivoted type carrying arm, a key operated lever, a key depressible to swing said lever in one direction, a normally flexed toggle connecting said arm and lever for swinging of said arm by said lever, upon depression of said key, until said toggle is fully straightened, and a second normally flexed toggle including a pair of link elements respectively pivotally anchored to said arm and to the supporting framework of the machine and also including hinge means jointing said links to unfold about successively effective parallel hinge axes, one of which hinge axes passes between the toggle anchorages as th first mentioned toggle becomes fully straightened by depression of said key, and the other one of which hinge axes is thereafter effective to permit further extension of the second toggle for thrusting of the type into printing position by said second toggle, said second toggle including means for storing type impressing energy therein during straightening of the first toggle.

8. In a front strike typewriting machine having a work backing platen, a type action comprising a type bar pivoted on the supporting framework of the machine to swing rearwardly toward the platen about a horizontal axis to effect a type impression and carrying a type adjacent its free end for impression effecting coaction of the type with the front of the platen, key operated means for swinging said bar toward the platen and checking the bar with the type slightly short of the platen, and a normally downwardly flexed toggle having one of its links pivotally anchored to the supporting framework of the machine and the other one of its links pivotally anchored to said type bar adjacent the type, the anchorage axes extending horizontally transversely of the plane of movement of the type bar, the frame anchored link of said toggle being a heavy momentum accumulating link and the other link being a light link, said toggle including means hinging its links to each other to unfold, on the printing stroke of the type bar, about successively effective parallel horizontal hinge axes extending transversely of the plane of movement of the type bar, the first effective one of which hinge axes passes upward between the link anchorages before the type reaches its printing limit and is effective until said hinge axis reaches a straight line passing through the two anchorage axes.

9. In a typewriting machine, a silently printing type action comprising a type carrier, and a toggle for controlling and effecting the final motion of said carrier to theprinting limit of motion of the carrier, said toggle comprising two links anchored respectively to the carrier and the supporting framework of the machine, means forming a lostmotion pin and slot hinge connection. between said links, the slot extending substantially longitudinally of one of said links, resilient means for normally taking up lost-motion in said connection, and means to cause said links to fulcrum one on the other at one side of the slot of said pin and slot connection following a movement of the type carrier to a point which brings the pin to a straight line connecting the link anchorages.

10. In a typewriting machine, a silently printing type action comprising a type, an oppositely movable element connected with the type to advance the type positively to an impression limit and restore the type positively to a normal idle position, means for initiating a type advancing movement of said element, and normally collapsed toggle means independent of said firstmentioned means for controlling and effecting the final portion of the type advancing movement of said element, said toggle means comprising two links pivotally anchored one to said element and the other to the supporting framework of the machine and hinge means connecting said links, the link anchored to the framework being a weighted momentum accumulating link and the other link being a light link, the hinge means connecting said links including normally spaced means engageable, as the type nears its impression limit, for toggle-expanding ful-' cruming of the links on each other to complete final type advancing movement of said element by toggle pressure.

11. In a front striking typewriting machine, a work backing platen, a type bar pivotedgon the supporting framework of the machine to swing rearwardly toward the platen on its printing stroke about a horizontal axis and carrying a type coactive with the front of the platen, means for initiating a printing stroke of the type'bar and checking said stroke as the type reaches a point close to the platen, and a normally collapsed toggle having one of its links pivotally anchored to the type bar adjacent the type and its other link pivotally anchored to the support-' ing framework of the machine, the latter link being a heavy momentum accumulating link and the pivotal anchorage axes of the links being parallel and horizontal, said links having normally separated means rockably engageable for toggleexpanding fulcruming of the links on each other about a horizontal axis parallel to the anchorage axes to effect the final portion of the printing stroke of the type bar, and said links also having a pin and slot hinge connection therebetween fulcruming the links on each other for unfolding about a horizontal axis parallel to the other axes until said normally separated means engage, the slot of said pin and slot hinge connection extending substantially longitudinally of one of said links at all times, said pin and slot hinge connection including a spring arranged to resist movement of the pin of said connection from one end of said slot toward the other end of the slot by the fulcruming of the links on each other incident to rocking engagement of said normally separated means.

12. In a front strike typewriting machine, a work backing platen, a type bar pivoted on the supporting framework of the machine to swing rearwardly toward the platen on the printing stroke of said type bar about a horizontal axis and carrying a type coactive with the platen at the front of the platen, means connected to said type bar to initiate a printing stroke of the type ,5 bar and to check saidstroke as the type nears printing position, and a normally downwardly collapsed toggle havinga pair of rigid links respectively anchored to said bar adjacent the type andto the supporting framework ofthe machine and hinge means connecting said links to each other to unfold during the printing stroke of the type bar to first one and then toward the other of two fully extended conditions of, said toggle in moving, toward the latter one of which said conditions the toggle is further extended over its first fully extended condition to complete the printing 'stroke'of the type bar, by toggle pressure, said toggle including means for storing energy therein during unfolding there of to the first one of said fully extended conditions thereof and for expending said stored en'- ergy to. extend said toggle toward the second one of said fully extended conditions thereof.

:1 3. In a front strike typewriting machine, a type'action comprising a lever having twoarms respectively extending generally fore and aft of the machine in different directions from a hori zontal axis, an arm'fulcrumed on a horizontal axis directly-below the fulcrum of said lever and extending forwardly of the machine farther than the forward arm of said lever, a type key, a key carrier'pivotally anchored to the forward ends of said lever and arm, atype bar having a type carrying arm and a secondarm andpivoted on the machine framework for swinging of its type-carrying arm abouta horizontal axis rearwardly-toward the platen, a link connecting said second type bar arm to the rearwardly extending arm of said lever, a rest for the type carrying arm of said type bar, a return spring connected tosaid link to restore'the typebar to a normal idleposition in which said link and said arm of the type bar form'a normally downwardly collapsed toggle fully extensible bydepression of said key,

and a second normally collapsed toggle including two links respectively anchored to the supporting framework of the machine and to the type carrying arm of said type bar and hinge meansconnecting said links to unfold on a printing stroke of the type barabout first one and then the other of two parallel horizontal hinge axes to first one and then toward the other of two fully extended toggle limits in expanding toward the second of which limits the expanded length of the toggle is increased.

14. A front strike typewriting machine as claimed in claim 13, wherein said return spring is connected to the first-mentioned link and to the supporting framework of the machine to swing about its frame anchorage substantially without stressing the spring during the initial portion of the printing stroke of the type bar.

15. In a typewriting machine having a framework, a type action mounted in the framework comprising a type carrier mounted for movement from a retracted limit to a printing limit, key controlled means for initiating movement of the type carrier from its retracted limit toward its printing limit, normally collapsed means anchored to the framework and to the type carrier and extending therebetween independently of said key controlled means for expansion of said normally collapsed means by the type carrier into a taut type carrier snubbing condition before the type carrier reaches its printing limit, and, means carried by said normally collapsed means to automatically effect an additional momentary expansion of the normally collapsed means following tautening of the latter me ns tothereby briefly press the snubbed type carrier to its printing limit.

16. In a typewriting machine having a framework, a type action mounted in the framework comprising a type supported for movement from a normal retracted limit to an impression limit and back again, anormally collapsed toggle having 'two links and hinge means connecting the links for unfolding thereof about first one and then the other of two parallel hinge axes during movement of the type from its retracted limit to its impression limit, one link of the toggle being connected with the framework and the other with the type for an initial full straightening of the toggle by unfolding of the links about the first one of said hinge axes as the type nears its impression limit to thereby snub the'type, and momentum accumulating means associated with said toggle to' first acquire momentum and thereby store energy therein-during said initial full straightening of said toggle and to thereafter automatically transmit its stored energy to the toggle to efiect unfolding of the toggle links about the second one of said hinge axes and thereby press the type to its impression limit through the medium of said toggle.

17. In a typewriting machine having aplaten .for backing paper to receive type impressions, a

type action comprising in combination, a type, a type carrier to which which is mounted for type protracting and retracting strokes respectively toward and from the platen between a normal retracted limit and a protracted limit -at which type protracting strokes of the carrier end, a normally collapsed device having a fixed anchorage and an anchora e movable from and toward said fixed anchorage and positively connected to th carrier for expansion of said device during type protracting strokes of the carrier and collapsing of said device during type retracting strokes of the carrier, said device including means activated by an initial expansion of said device to thereafter thrust the movable anchorageof the device farther from the fixed anchorage'to complete a type protracting stroke of the carrier, resilient means carried by said device and connected said type is fixed and 2' asses-1e therewith for control by expansion and contrac-' tion 'of said device to yieldingly resist expansion of said device during only a minor final portion of each type protracting stroke of the car rier and exert a collapsing effort on said device during only a corresponding initial portion of each type retracting stroke of the carrier, and typing operation initiating means connectedwith the interconnected carrier and device for transmitting type" protracting, power thereto during only an initial portion of each type protracting stroke of the carrier. 18. In a typewriting machine having a platen for backing paper to receive type impressions, a type action comprising, in combination, a type, a type carrier to which the type is fixed and which is mounted for type protracting and retracting strokes respectively toward and from the platen between a-normal retracted limit and a protracted limit at which type impressing actions end, a normally collapsed pressure toggle having a fixed anchorage and an anchorage positively connected with the type carrier for expansion of the toggle during type protracting strokes of the carrier and collapsing of the toggle during type retracting strokes of the carrier, momentum accumulating means carried by the toggle for actuationof said means during initial expansion of the toggle to acquire energy and for ubsequent energy expending action'of said means on the toggle to continue expansion of the latter to press the type carrier to its protracted limit, resilient means carried by the toggle and connected therewith for automatic conditioning of said means by the expanding, and contracting actions of the toggle to exert a toggle collapsing efforton the toggle during only the final portion of each type protracting stroke and a corresponding initial portion of each type retracting stroke of the type carrier, and typing operation initiating means connected with the interconnected toggle and carrier for transmitting type protracting power thereto during only an initial portion of each type protracting stroke g of the carrier. 3

- JOSEPH P. BARKDOLL.

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