US2156000A - Typewriting machine - Google Patents

Description

TYPEWRITING MACHINE Filed Jun 21, 1937 6 Sheets-Sheet 1 INVENTOR RUSSELL G. THOMPSON ATTORNEY April 1939- R. G. THOMPSON TYPEWRITlNG MACHINE 6 Sheets-Sheet 2 Filed June 21, 1937 INVENTOR RUSSELL 6. THOMPSON m I 3 Q s 5 k E 5 W ,.m o..l..r 7 1 \0 E h w m w km %S April 1939- R. G. THOMPSON 2,156,000

TYPEWRITING MACHINE Filed June 21, 1957 6 Sheets-Sheet 3 INVENTOR RUSSEL L G. THOMPSON TTORNEY THOMPSON P il 25 ING MACHINE 6 S'neet 4 F51? me 21, 193? 7 \M 6 w z a m In W U J April 25, 1939. R. e. THOMPSON TYPEWRITING MACHINE 6 Sheets-Sheet 5 Filed June 2l, 1937 INVENTOR RUSSIELL a. THOMPSON BY ATTORNEY April 25, 1939.

R. G. THOMPSON 2,156,000 TYPEWRITING MACHINE Filed June 21, 1937 6 Sheets-Sheet 6 Z IIIIIIIII IIIII w INVENTOR I RUSSELL G. THOMPSON BY Patented Apr. 25, 1939 UNITED STATES PATENT OFFICE mnwnrrma mom Russell G. Thompson, West Hartford, Conn, as-

signor to Underwood Elliott Fisher Company, New York N. Y., a corporation of Delaware This invention relates to typewriting machines and with regard to certain more specific features thereof to an improved type action and means for eflecting and controlling the movement of'the parts thereof. While the invention is shown and described in connection with a power-driven typewriter it will be obvious that several features of the invention are applicable to manually operated machines. 4

The invention has for one of its objects to provide a group of type actions each of which is suited to the particular requirements of a powerdriven machine. It is well known that suchma chines present a particularly diflicult'problem' because of the shocks incident to the engagement of the individual type actions with the driving means, and also because of the peculiar character of the blow on the engaged member by the driving means. In power-driven typewriters the mechanism for accomplishing the movement of the type bar to and from the platen is entirely removed from the control of the operator and the action of the power means when engaged is inclined to loosen and destroy the parts of the type action and increase the noise incident to all contac s.

Another difl'iculty presented by the employment of the power-drive unit and the shock incident to engagement therewith is the tendency of the type bar to vibrate as it approaches the platen in consequence of which the type bar is apt to impinge on the type bar guide adjacent the printing point and destroy the regularity of the writing and also result in exceptional wear of the parts. I

The type action here involved is of the noise less character and it is an object of the invention to so improve and modify such a type action as to make it capable of substantially silent power operation without the interposition of any elastic or yielding connections between the powerdrive unit and the type bar, it being particularly an aim of the invention to adapt the thrust principle of operation of a type bar to a fluted roller or.1 other form of constantly operating powerdrive unit so that the labor of the operator is reduced to the mere selection of the proper keys and engagement thereby of the actuating device of the type bar with the power-drive.

Itis a further aim of the invention to produce a quiet power-driven machine in which the thrust principle of type bar operation is used in connection with a standard four-bank keyboard and a single shift platen, and in which a number of type bars segmentally arranged for selective advance to the printing point are provided with upper and lower type heads each of which may have two type characters, the movement of eachtype bar in connection with such a construction being in variable paths controlled by diflerent keys at the keyboard.

Another object of the inventionis to insure the continuance of a toggle locked position of the supporting means for the forward end of the type bar as it completes its movement to the 10 platen andlto a reasonable extent away therefrom whether the type bar be moved in one path or the other by the selection of one or the other of the two keys which control its operation. Thus the pivotal axes of the bar areheld firmly when the bar is in the vicinity of the type g de and vibratory tendencies are checked.

Other objects are to provide improved means for deadening the sounds originating in contacts of the various parts of the action. This includes the contact of the type-with the paper onthe platen, the stopping of the power-drivelever in its advance of the typebar and the return of the energy storing device or hammer to its position of rest.

Another object of the invention is to provide a sturdy, inexpensive and generally improved power-drive unit between the selecting keys and the type bars, such unit being extremely compact and quiet in its operation and being especially adapted to the actuationof a series of type bars arcuately arranged above the unit, and correspondingly suited to a control of the carriage in its escapement, case shift, return and back spacingmovements.

Other objects will be in part obvious and in part particularly pointed out as the description of one preferred embodiment of the invention proceeds.

In the drawings: i

Fig. 1 is a view in top plan of a power-driven typewriting machine comprising the present invention.

Fig. 2 is a, view in fore-and-aft section of the I machine shown in Fig. l.

45 Fig. 3 is a fore-and-aft sectional view through the machine showing the type action advanced from its normal position of rest, as shown in Fig. 2, to a position of lower-case printing by th upper head of the type bar. I

Fig. 4 is a fore-and-aft sectional view through 'the machine showing a type action advanced 3, but with the platen elevated to receive the imprint of the upper case character of the upper head of the type bar.

Fig. 5 is a fore-and-aft section through the machine showing the same type action as seen in Figs. 2 to 4 inclusive but as viewed from the opposite side and with the type bar in its retracted position.

Fig. 6 is a' fore-'and-aft section through the frame showing the same type action as seen in Fig. 5 but as operated by the selection of another key at the keyboard to advance the type bar for printing by a lower-case character on the lower head of the bar. 8

Fig. 7 is a view in perspective of one of the type action hangers.

The machine is shown generally in Figs. 1 and 2 of the drawings. It comprises a frame having side walls 2| and 22 connected by a front bar 23 and by a rear bar 24. The side walls are further connected by a bar or backbone 25, cross bars 28 and 21 and atop plate 28.

The top plate has an arcuate bar 38 upon which are mounted the forward ends of a multiplicity of type actions indicated generally at 3|. The type actions are radially arranged and have rear supports in an arcuate bar 32 fixed to the top plate and provided with comb slots 33 to guide type bars 34. The latter are further guidedby comb slots 35 and 38 in arcuate webs 3'! and 38 projecting downwardly from a guide member 48 suitably mounted on the top plate below a cover 4|.

Toward the rear of the machine a center-tie 42 is adjustably fixed for slight fore-and-aft movement on a cross bar 43 and this center-tie carries the pivotal supports for a case-shifting rocker- 44, arms 45 of which pivotally support a track 41 which through anti-friction bearings supports a. carriage rail 48 connected to suitable carriage end frames-in which a roller platen 58 is mounted. The carriage also includes a rail 5| which, in the transverse movements of the carriage, is biased against a forward face of an upstanding arm 52 of the center-tie. A backing screw 53 is threaded in the upper portion of the rear wall 24 and suitably resists printing pressures on the platen. This center-tie construction and the means for ad- J'usting the center-tie relatively to the frame are described and claimed in my copending application filed Feb. 20, 1937, Serial No. 126,902.

A'magazine 55 is secured to spaced webs 56 extending rearwardly from the center-tie and contains one or more tabulator stop blades 51 adapted .for poweroperation, as clearly shown and described in my copending application filed April 1, 1937, Serial No. 134,324.

Any desired means may be employed for raising and lowering the carriage frame and consequently case-shifting the platen, but it is preferred to make use of a link 58 having its upper end connected to the rocker frame 44 and its lower end connected to a link 68 by a pivot stud 6|. The link 68 in turn is pivotally connected at 62 with an arm 63 adjustably secured to the frame of the machine. When the toggle involving links 58 and 881s straightened the forward side of frame 44 is elevated depressing the pivotal conmedian 45 and lowering the platen to its normal or lower case position. This position is deter- 1 58 and link 68. Lever arm- 68 is suitably connected to an actuator 18 which carries pawls adapted to be moved into engagement with a toothed drive shaft 1! by operation of a case-shifting key at the keyboard. Depression of this key causes a pawl to engage 0n the forward side of drive shaft II and be moved downwardly carrying the actuator 18, which breaks toggle 58-68, pulling link 58 downwardly and rocking frame 44 to elevate the carriage until the head of pivot stud 66 comes against a cushion stop 12 at which time a toggle comprising links 61 and 68 is straightened to hold the carriage in upper case position until the de pressed case-shift key is released. Upon release of the key a pawl at the rear side of the drive shaft engages the unit to move the actuator 18 upwardly and return the parts to original position with head of stud 66 against a stop 59. The case-shift mechanism herein briefly mentioned is fully described and claimed in my copending application filed Feb. 20, 1937, Serial No. 126,904.

An electric motor is positioned in a casing I3 at the rear of side wall 22. The motor is connected to continuously rotate the power-drive member H which, in the present preferred form of the invention, is a toothed roller extending almost entirely across the machine and rotating in a counterclockwise direction, as viewed in Fig. 2 of the drawings.

Provision is also made for returning the carriage to commence a new line of writing by momentarily connecting the motor with a drum indicated at 14, which winds up a tape 15 connected to the carriage and line-spacing mechanism, and restores the carriage to starting position. The connection is made through a friction clutch indicated at 16 which is rendered effective by pressure upon the carriage-return key at the keyboard (see Fig. 1). This carriage-return mechanism, together with means forline-spacing on each return and for power-driven additional linespacing, is clearly shown and described in my oo-pending application filed Feb. 20, 1937, Serial No. 126,983,'now Patent No. 2,103,921, issued Dec. 28, 1937.

In the present embodiment of the invention shown in the drawings the top plate 28 is adapted for the mounting of twenty-two type bars. Each of the type bars is adapted for actuation by the operation of either-of two keys at the keyboard. Except for minor differences due to the variations in angularity of mounting, all the type bars and their associated parts are idGI'ifi'.

cal and the following description of one type action will be sufficient for the purpose of the present case.

In Fig. 7 of the drawings an improved hanger 88 is shown. This hanger is made up of two or more thin metal pieces which may be held'together by spaced rivets or suitably spot welded. Thus a laminated hanger structure is produced which includes an arm 8| adapted to fit into a slot 82 cut in the arcuate bar 38 of the top plate 28. The laminated hanger 88 also comprises an arm 83 which is notched at 84 to fit it over a rib 85 on the arcuate bar 32. A lower lip 86 of arm 83 fits in a radial slot through the bottom of bar 32 so that by the slots in the bottom of bar 32 and the slots in bar 38 the hangers 88 of a complete series are definitely located in substantially radial arrangement.

The hangers 88 are also provided with cushion stop and noise reducing features in the form of a slender bent-over finger 81 of the laminated hanger and in the form of a pile or bank 88' of very thin metal strips arranged along the top of arm 8I and held in position thereon by straps 99 at opposite ends of the bank. The laminated finger 81 serves to cushion the blow and reduce the noise of impact of the lever which drives the type bar forward toward the printing point. The bank 88 of superposed thin spring metal strips cushions and reduces the noise of impact incident to the return of the type, bar.

The hanger 89 is laminated in major part but beyond the arm 83 one of the sheet metal laminations is carried beyond the laminated structure providing an arm 9I whichserves as a pivot support, as will hereinafter appear.

The type bars 34 suitably guided in comb slots 33, 35 and 36 are supported for pivotal movement on the hangers 89. Each type bar is connected to its hanger by two links 92 and 93. The link 92 is pivoted to the type bar 34 at 94 and the lower end of link 92 is pivotally connected at 95 to an arm 99 which is adjustably fixed to the hanger 89. The link 93 has its upper end pivotally connected to the type bar 34 at 91 and its lower end connected to a rocker arm or link 98 which is pivoted at I99. at the extreme end of arm 9I which was heretofore described as a continuation of one of the laminations of hanger 89. Thus it will be seen that link 92 has its lower connection substantially fixed except for possibility of slight adjustment provided by eccentric adjusting device I9I. Link 93, however, has its lower pivotal connection on rocker arm or link 98 and the axis of motion of link 93 may therefore be varied.

The type bar 34 is also connected to the hanger so through a toggle indicated generally at I92 comprising links I93 and I94. Link I93 comprises two uniformly shaped sheet metal pieces provided with a suitable spacer at I95 and is pivotally connected to the type bar 34 and link 92 at the pivot 94. The ends of the spaced members are brought together as indicated at I99 and I91 and at end I91 link I93 passes between spaced sides of link I94 and is pivoted thereto at I98. The other end of link I94 is pivoted to the hanger 89 at II9.

Link I94 is provided on both sides with arms III between which an end II2 of a hammer H3 is pivoted. A driving lever H4 is pivoted to hanger 89 at H5 and has a curved face II6 underlying the hanger'89 and the levers on opposite sides of the hanger as will hereinafter appear. Lever I I4 has arms II! extending upwardly on opposite sidesof hanger 89 and their upper ends fork around hammer H3 and are pivotally secured thereto at II8. AL bridge I29 joins the opposite sides of lever H4 and the lever is adapted, upon movement in a clockwise direction, as viewed in Fig. 2 of the drawings, to tension a spring I2I until bridge I29 abuts the finger stop 31 of the hanger.

Such movement tends to straighten the toggle I92 and advance the type bar 34 toward the platen 59. As will later appear, the driving lever M9 is not given its entire throw to stop position under {direct control of the power actuators of the machine, but instead the lever is moved part way under direct control of the power actuators and the final throw of the lever and consequent final advance of the type bar is efiected by the momentum accumulator or energy storing device 8 it? which ultimately straightens the toggle I92 and applies suitable printing pressure to whichever type is at the printing line. To vary this pressure the platen is adjusted fore and aft of the machine by a hand wheel I22 on screw 59,

3 and 4. The movement of the axis X from one position to the other and the fixing of the axis in the different positions is effected by a system of levers and toggle links which will be later described. The power drive mechanism comprises primarily the toothed or fluted roller H which is continuously rotated in a counter-clockwise direction, as viewed in Fig. 2, from the electric motor positioned in the casing 13. The backbone 25 has a flange I23 extending downwardly at a right angle to its body. It also has an upwardly extending flange I99 and a rearwardly extending flange I I9. By a circular gang cutter a series of slots I24 is cut in the rear of the backbone and these slots are cut deep enough that the peripheries of the cutters pass through the flanges I99 and H9 and through the shoulder formed by the body and flange I23 of the backbone. Thus at I25 (Fig. 2) the slots extend entirely through the backbone for a purpose which will later appear. In each of the slots I 24 an actuator I29 is arranged. These actuators are substantially uniform in character having an easy sliding movement in the slots and they are located in transverse alignment by a pivot pin or rod I21 which passes through the flange H9 and through a vertical slot I28 in each of the actuators. Each of the actuators carries a pawl I39 pivoted thereon at I3I and having teeth I32 to engage with the teeth of drive shaft 1|. A forward edge I33.of each actuator bears against the rear face of flange I23 of backbone 25 and is normally held thereagainst by a spring I34 the lower end of which engages a lower arm I35 of the actuator and the upper end of which is connected to an anchor plate I39secured to the underside of flange I23. Spring I34 causes the actuator to pivot around pin I21 and hold pawl I39 normally out of'engagement with the drive shaft.

A standard 4 band keyboard is indicated at I31. Each character key on the keyboard is associated with a key lever I38 the end I49 of which extends into one of the slots I24 in the flange I99 of the backbone and is pivotally connected therewith by a pivot pin I4I. Each key lever also has an arm- I42 which carries a dog I43 pivoted at I44 and normally held in the position indicated in Fig. 2 by a spring I45. Each dog E43 passes through the opening provided at I25 by the gang cutting of slots I24 and, therefore, for each actuator arranged within a slot I 24 there is a dog H93 in the same slot in position to move the actuator upon depression of the corresponding key lever I38. Such lever movement engages pawl i39 with drive roller 1| which causes an approximately 30 rotation of pawl 539 against a suitable stop and a simultaneous downward movement of the actuator. The engagement of the first tooth of the pawl leads the second tooth into actuating engagement with the next tooth of the drive roller. A lug I49 near the lower end of the actuator passes between the balls of a crowder lock I41 and simultaneously the actuator picks up a universal bar E98 and rocks it for the purpose of efiecting escapement and ribbonvibration operations. As 7 the actuator proceeds downwardly in engagement with the drive roller a cam edge I50 of the actuator engages an adjustable throw-off screw I which insures disengagement of pawl I30 with the driving shaft and causes it to be returned to the control of spring I 34 which eventually draws the actuator back against the rear face of the backbone.

In addition to the actuators which are placed in engagement with the drive shaft by operation' of the character keys, there are similar actuators in the same row undercontrol of the space bar (indicated at I52 in Figs. 1 and 2), the carriage shift key, tabulator bar I49, and various other keys controlling the operation of the typewriter. These actuators are all carried by the backbone which also guides and pivots the key levers and also guides the actuating dogs, the function of which is to engage the actuators with the driving shaft.

A bar I53 of sound deadening. material such as rubber or leather extends transversely on the machine in a metal support I54 and is adapted to receive the impact of arms I35 of the actuators as they are thrown off by screws I5I and returned to normal position by their return springs I34. The face of bar I53 is set at a slight angle so that as the actuator returns upwardly to its original position the end of arm I35 may slide along this face until eventually the actuator is deposited against the backbone. All of the key levers have return springs I55 connected to an adjustable anchor plate I56. The springs normally hold the key lever against an upper stop I51 of cushioning material and the key levers have a uniform movement of depression to a lower stop I58, as clearly described and claimed in my copending application filed Feb. 20,1937, Serial No. 126,905.

According to the present invention, each type bar is controlled by two different keys and consequently by two actuators. Preferably, therefore, the actuators I26 are arranged in successive pairs across the machine. From the upper ends of .the actuators of one pair links I60 and I6I extend respectively to opposite sides of each hanger 80. Link I60 is pivotally connected at I62 to a rock lever I63 which is pivoted on the hanger 80 at I64. This lever has a circular 'hole I65 within which extends a stop pin I66 extending laterally from the hanger 80. The hole I65 and pin I66 determine the extremes of movement of lever I63. Thus, viewing the construction in Fig. 2 of the drawings, as an actuator I26 is engaged with the power drive shaft and moved downwardly, link I60 pulls down the forward end of lever I63 until the lower edge of hole I 65 abuts the stop pin I 66. The rear end of the lever is thus thigiwn upwardly to a stop position, which is clearly shown in Fig. 4. This end of the lever is pivotally connected to one end of a link I61, the other end of which is pivotally connected at I68 intermediate the pivoted ends of a link I10. The lower pivoted end I1I of this link is connected to rocker 98 which, as heretofore described, is pivoted at I 00 on the end of the hange1-80 and the other end of which carries the variable pivot X of link 93. The upper end of link I10 is connected by a short link l12 wit'h a bracket arm I13 fixed to the hanger 80. Thus a downward pull on point I 62 of the lever I63 straightens a toggle from stop I66 through the lever I63 to a toggle point T, thence through link I61 to pivot point I68 (see Fig.3); This type bar has substantial 98 and the pivotal axis X. While this toggle is straightened the point X will not vary.

As lever I 63 is being pulled down to its stop position by its actuator and link I60, 9. forward rocker end I14 of the lever engages with curved face II6 of the drive lever H4 and rocks the drive lever around its pivot II5 to commence the straightening of toggle I02. Lever I63 arrives at its stop and toggle-locked position before the drive lever II4 has completed its full movement. It is at this point that the energy storing device II3 picks up the movement of the type bar and carries it forward until bridge I20 of the drive lever strikes against stop 81 at which time the toggle I02 is straightened and the lower case type of the upper head of type bar 34 is brought into printing engagement with the paper on the platen (Fig. 3). I

Lever I63 has its rocker end supplemented by a guard I15 pivoted to the lever at I16 and pressed by spring I11. to normally hold a stop lip I18 on the guard against the rocker end of the lever. The drive lever II4 has a laterally extending pin I80 which rides along the upper edge of guard I15 when the hammer I I3 is in control of the movement of the type bar toward the platen. Spring I2I returns the drive leverI I4 in the opposite direction and during the first part of this returning movement pin I 80 rides along the top edge of guard I15 in the opposite direction. Therefore, the toggle comprising lever I63 and link I61 may not be broken from the time that the hammer I I3 has started to pick up the movement of the type bar to the time that this hammer has returned under the influence of the spring to a point in th operation in which the ty moved away from the printing point. The spring I2I continues to return the drive lever until the hammer H3 is rocked back onto the bank of thin strips which constitute its cushion stop, as heretofore described.

While the pin on the drive lever is riding along the guide I15 in one direction or the other, the

corresponding actuator I26 is, of course, held against return to its upper normal position although it has been rejected from its engagement with the driving shaft by the engagement of throw-off pin I5I with cam edge I50 of the actuator. As soon, however, as the pin I80 rides over the end of guard I15 the actuator is returned upwardly by its spring I34 and carries with it the connector I60 thus moving upwardly the rocker end of lever I63 breaking the toggle I63-I61 and swinging the axis of movement X of link 93 substantially toward the position shown in Figs. 5 and 6 of the drawings.

An adjacent actuator I26 controlled by another character key at the keyboard has its upper end connected by connector I6I to a lever I8I pivoted at I32 on the opposite side of hanger 80. This lever has a rocker end I83 adapted to engage the curved face N6 of the drive lever II4 to move the drive lever in the same manner as ,moved by lever I63 to institute the straightening of toggle I02 and thrust the type bar 34 toward the platen. However, lever I 8I when moved by its actuator first straightens the toggle comprising the links I10 and I12 against a. guard I19 and moves the rocker 98 into a firmly held position indicated in Figs. 5 and 6 of the drawings. This is accomplished in the following manner.

It is possible that the return of theactuator for lever I63 may have been of sufiicient energy to' throw the lever over until the upper side of hole 75 165 contacted with the pin I99 m which case thetoggle "Ila-I12 would be straightened and the parts would appear in the position shown in Fig.

5 of the drawings even though connector "I had. 'not been pulled down by its actuator. When the actuator is pulled down the lever I9I, being notchedat I95 around a stop pin I96 which extends from the side of the hanger, is swung from the position shown in Fig. 5 until it is stopped by engagement with pin I86, as shown in Fig. 6 of the drawings.

link I81 which lies beneath the hanger 90 with which the type bar is moved'forwardly by the an arm I88 of a bell crank lever I99 pivoted at I9I on the Hanger 89. The other arm I92 of the bell crank lever lies on the side of the hanger opposite lever It and its end is adapted to engage with lever I63 just above the hole I65. Swinging i of lever I8I to its stop position as shown in Fig.- 6 of the drawings operates the bell crank lever I90 to throw lever I83 downwardly-until the upper side of the hole I65 engages the stop pin I69.

drive lever in a different path to impress the lower case character of the lower head of the type bar against the paper on the platen. The lever I BI is supplemented by a guard I89 similar to the one, on lever I93 and the drive lever has on its opposite arm II! a pin I92 which drives in .the nected to the bar andits other end pivoted in fixed relationto the hanger, a rocker member same manner over the guard I89 preventing any disturbance in the position of the pivotal point of link 93 while the hammer H3 is in control of the advance or retraction oi the type bar.v

For upper case printing by either the upper or lower heads of the type bars the carriage is shifted to an upper toggle-docked position by actuators similar to those described in connection with the character keys and as more particularly described and claimed in my copending applica tion filed Feb. 20,1937, Serial No. 126,904.

The carriage is provided with a letter feed escapement indicated at I93 operatedfrom the universal bar I48, which is in turn power operated as any character lever or the space bar is depressed. This escapement includes a shaft I94 splined at its lower end to accommodate the carriage to escapement in either upper or lower case position, and the upper end of this shaft is provided with a pinion I95 meshing with a rack I99 on the carriage. The escapement dogs are thrown out of engagement when tabulating, as clearly shown and described in my copending application filed April 1, 1937, Serial No. 134,324.

What is claimed is? i,

1.- In a typewriter, a frame, a plurality of type actions segmentally arranged relatively to said frame, each type action comprising a hanger secured to the frame, a type bar, a toggle between the type bar and the hanger; a supporting link This lever is connected by curved for the type bar having one end pivotally connected to the bar and its other end pivoted in fixed relation -to the hanger, a rocker member pivoted on the hanger, a second type bar supporting link having one end connected to the type bar and its other end connected to the rocker member on one side of its pivot, a toggle link extending from said rocker member at the other side of its pivot, another toggle link having one end pivotally connected to the first said toggle link and its other end held fixed for pivotal movement relatively to the hanger, a lever pivotally mounted on one side of the hanger, a toggle link pivoted to the first said toggle link having its end connected pivotally with an end of said lever,

means for connecting the other end of said lever .to an actuator, means for limiting the range of pivotal movement of said lever, another lever pivotally mounted for movement in a limited range at the other side of the'hanger and having means for connecting one end with an actuator, a finger connected for movement by the last said lever to insure straightening of a toggle comprising the first and second said toggle links, and a driving lever operable by either of the aforesaid levers to actuate the toggle between the type .bar and the hanger.

2. In a typewriter, a frame, a plurality of type actions segmentally arranged relatively to said frame, each type action comprising a hanger secured to the frame, a type bar, a toggle between the type bar and the hanger, a supporting link for the type bar having one end pivotally conpivoted on the hanger, a second type-bar-sup porting link having one end connected to the type bar and its other end connected to the rocker member on one side of its pivot, a toggle link extending from said rocker member at the ment relatively to the hanger, a lever pivotally mounted on one side of the hanger, a toggle link pivoted to the first said toggle link having its end connected pivotally with an end of said lever, means for connecting the other end of said lever to an actuator, means for limiting the range of movable by its accumulated energy, to straighten the toggle between the type bar and the hanger. RUSSELL G. THOMPSON.

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