US1945097A

US1945097A - Typewriting machine

Info

Publication number: US1945097A
Application number: US544345A
Authority: US
Inventors: Russell G Thompson; Chester W Crumrine
Original assignee: ELECTROMATIC TYPEWRITERS Inc
Current assignee: ELECTROMATIC TYPEWRITERS Inc
Priority date: 1931-06-15
Filing date: 1931-06-15
Publication date: 1934-01-30
Anticipated expiration: 1951-01-30

Description

4 sheets-sheet 1 R. THOMPSON ET L TYPEWRITNG MACHINE Filed June l5, 1931 Jan. 30, 1934.

R. G. THOMPSON Er AL TYPEWRITING MACHINE Filed June 15. 1931- 4 sheets-sheet 2 .C .EL

S vmh m: mln vh @im imm INVENToRs RUSSELL G. THOMPSON .Y cgi-:STER w. CRUMRINE ATroRNEY Jan. 30, 1934. i

RG. THOMPsN Er AL l Jan. 3o, 1934.

R. G. THOMPSON ET AL y F v RUSSELL s. THOMPSON mn' l v PBESTER wcRuMRfNE 1 r l I l ATTORNEY Parella-d Jan. 3o, 1934 UNITED STATES PATENT OFFICE 1,945,091 mEwarrING yimonline tion of New York l.application June 15,1931. serial No. 544,34'5

I s Claims.

This invention relates to improvements in typewriting machines, and particularly to devices for shifting the platen and the type.bars relatively to each other for changing from upper to lower case type, and vice versa.

The principal object of this invention is the provision of simple and inexpensive means for shifting the 'platen and type bars relatively to each other for changing case, said means'being so arranged that the load on the actuating parts is reduced to a minimum, resulting in substantially noiseless operation.

Another object of the invention is to mount the shiftable part in a case shift mechanism on the free ends of a plurality of springs, which tend to resiliently move it toward one case position and guide its movement toward and from the other case position.

A still further object of the invention is the provision of resilient guiding members on a ilxed part, each of which is arranged between a pair of xed stops on the movable part and which is engaged by one or the other of said stops before the shiftable part reaches the limit of its movement and serves to slow up its movement and eliminate the noise normally caused by the force of impact.

Still another object` of the invention is the provision of simple and readily accessible means for adjusting the type basket to bring th concave types into proper engagement with the curved surface of a cylindrical platen.

Another object of the invention is the provision of means for shortening the path of movement of the type bar when shifted to writey upper case characters so that they will be struck with greater force than the lower case characters which have less printing surface area.

To these and other ends, the invention consists in the construction and arrangement of parts that will appear from the following description when read in conjunction with the accompany.

ing drawings, the novel features being pointed out in the claims at theend of the specification.

In the drawings:

Fig. 1 is a transverse section of a typewriting machine illlustrating one possible embodiment of the invention;

Fig. 2 is a similar view showing the parts in the other case position;

Fig.' 3 is a side elevation of a leaf spring for supporting and lifting the s'hiftable part;

Fig. 4 is a plan view of the same;

Fig. 5 is a fragmentary view illustrating certain of the shifting devices at the oppositeside of the machine in the Fig. 2 position;

Fig. 6 is an enlarged fragmentary of the type;

Fig. 7 is a fragmentary transverse section of a typewriting machine illustrating an arrangementfonvarying the force of the type blow on the platen when theA type basket is shifted from one case position to another; A

Fig. 8 is a similar view showing the type basket in another position; Fig. 9 is a view similar to Fig. 6 showing a modied type arrangement for use with the construction shown in Figs. 7 and 8, and Fig. 10 is a'fragmentary detail view-of a toggle lever and its actuator shown in rear elevation.

Although the invention as illustrated is embodied in a power driven typewriting machine, it will be understood that its use is not limited to such machines, but is applicable to various machines in which the type bars are shiftable relatively to the platen for changing case. This machine comprises a frame 1 in which a type basket 2 is movably mounted. A plurality of type bars, one of which is shown at 3, are pivotally mounted in the type basket for cooperation with the printing point on the platen. Each of the type bars has two types 5, one for lower and the other for -upper case printing. With the parts in the normal position shown in Fig. 1, the lower one of the types 5 engages the platen for printing when the type bar is actuated. When, however, the type basket is shifted to the Fig. 2 position, the other type 5 engages the platen for printing.

The type basket 2 is mounted on the free front ends of a plurality of leaf springs 6 and 7. It will be understood that.two of each of said springs are employed, one at each side of the type basket. The springs 6 are secured at their rear ends to brackets 8 projecting from the frame and extend upwardly and forwardly theredetail view from and at their free ends are secured to lugs in the embodiment illustrated comprises two tog' gles so arranged that one or the other is in its straightenedposition when the type basket is shifted to one or the other of its printing posi tions. One of said toggles comprises the link 12 pivoted at one end to a bracket 13 projecting rearwardly from the type basket. endof the link 12 is pivoted to the arm 14 of a bell crank lever fixed on one end of a rock shaft 15 mounted on a fixed part and extending to the other side of the type basket. The other arm 16 oi the bell crank is connected with a toggle lever 17 by -means of a link 18. By this arrangement, thelink 12 and arm 14 constitute in eect a .toggley moved to its straight lposition when the type basket is in its upper or normal position, as seen in Fig. 1. This toggle not only serves to raisethe type basket, but also to slow up and limit its upward movement. It will be noted that when the parts are in this position, the'pivotal points of the link 12 are in substantial alinement with the axis 15 of the bell crank.

The ltoggle lever 17 and link 18 constitute in effect a second toggle movable from the broken position shown in Fig. 1 to the straightened position shown in Fig. 2,'in which the pivotal points of the link l18 are in substantial alinement with the pivot 'of the lever 17 when the type basket is shifted to its lower position, and this toggle serves to slow up and limit the downward movement of the type basket.

Power driven key controlled means are pro vided for actuating said toggles to shift the type basket. Said. means comprises a power driven roller 2,0 and a bell crank pivoted at 21 adjacent thereto on the frame.l One arm 22 of the bell crank projects rearwardly from its pivot and has its free end connected with an arm 23 of a threearmed lever Yby means` of a link 24. Said threearmed lever is pivoted on the frame and has an arm 25rto which a rearwardly extending interponentl 26 is pivoted. The interponent 26 lies closely adjacent the lever 17 and at its end is provided with oppositely projecting fingers or

lugs

27 and 28 adapted to engage one or the other of a pair of cooperating lugs or projections 29 'and 30 projecting laterally from the lever 17,

and arranged on diametrically opposite sides of its pivot 17. The free ends of the lugs 'or

pins

29 and 30 are connected by means of a plate 26', as shown in Fig. 10, which serves to retain the interponent therebetween. The other arm 31 of Athe bell crank projects downwardly from the pivot 21A and has a cam 32 pivotally mounted thereon adjacentv its lower end and' arranged adjacent the surface of the power driven roller 20. The cam 32 has a pair of lugs 33 and l34 projecting laterally therefrom on opposite sides of its pivot, one or Athe other of which is engaged by a 'spring-pressedarm 35 pivoted on the arm 31 and which Atends to turn the cam into engagement with the roller 20. The cam also has a pair of laterally

projecting stops

36 and 37 arranged on opposite sides of andat different distances from its pivot and adapted to cooperate with a stop provided on the lower end of a lever -38 also pivoted on the arm 31. The upper end of the lever 38 is provided with a laterally projecting lug which is engaged in a slot in the endv of an arm 41 depending from a key lever 42 having a key 43 by which it may be manuallyy operated. The key lever is pivoted on a xed part and'has a, rearwardly extending arm 44 which is slotted at its end for engagement with an eccentrically adjustable stud 45 projecting laterally from the The other depressed while writing upper case characters.

In the illustrated embodiment, when the key is depressed, the lower end of the lever 41 swings forwardly and moves the stop or lug 46 on arm 31 fromvthe path of the stop 36 and into the path of the stop 37 and permits the cam to move into engagement with the power roller under the action of the arm 35.l By the engagement of lits arm 44 with the interponent 26, the rear end of the interponent is raised from .the position shown'in Fig. 1 to that shown in Fig. 2 when the key is depressed. If the key is held depressed, as shown in Fig. 2,.the` cam 32 is turned through one-half a revolution until its stop 37 moves into engagement with the stop 46 on the arm 38. During this movement of the cam, the arm 22 is depressed and swings the arm-25 forwardly and with it the interponent 26, which by its position engages the lug 30 with its finger I28 and swings the armor lever 17 about its pivot 17, which in turn swings the arm 16 of the bell crank forwardly to straighten the toggle17, 18, and moves the arm 14 rearwardly to break the

toggle

12,14 and swing the type basketdownwardly against the tension of the spring arms 6 and 7. The parts come to rest while the key lever is held depressed in the position shown in Fig. 2. When the key lever is released, the cam 32 is again moved into engagement with power driven roller and the interponent returned to the Fig. 1 position. The cam makes another half rotation, during which the interponent 26 is again actuated and engages the lug 29 on the lever 17 and swings the lever to break its toggle and at the same time swings the bell crank to again straighten the

toggle

12, 14 against the tension of the springs 6 and 7 to return the type basket to normal lower case position.

A spring 51 connects the arm 52 of the threearmed lever with the frame of the machine and vtends to resiliently retain said lever in its nor-'- mal position and to vreturn it and with it thev interponent 26 after each acutation. A stop 53 adjustably mounted on the frame of the machine is normally engaged by the arm 52 and limits the movement of the three-armed lever under the action of the spring. The stop 53 is inthe form of a' headed bolt adjustably secured in the frame of the machine. A stop 54 is mounted on the rear end of a resilient bent arm 55 secured to the frame at one end and having its free end Qn which the stop is mounted free from the frame. The stop 54 is engaged by a stop 56 on the vlever 17 when its toggle is straightened, and the resiliency of its arm serves to avoid the noise which might otherwise be caused by such engagement.

' Asstated above, the bell crank 14, 16 is mounted on a rock shaft 15 which lextends to' the right hand side of the type basket. Means operatively connected with said rock shaft are provided for shifting the right side of the basket simultaneously with the left side vso that all parts ,of the type basket move simultaneously in substantially parallel lines. To this end, a lever 61 is flxedly see Fig. 5, to which one end of a link 62 corresponding to the link 12 is pivoted at 63. The other end of the link 62 is pivoted to a bracket 64 secured to the right side of the type basket and corresponding to the bracket 13 at the left hand side of the basket. The le'ver 61 has an arm 65 projecting rearwardly from the pivot 63, as seen in Fig. 5, which ,is ladapted to engage the bracket 64 Awhen the toggle, comprising the link 62 and the. lever 6l, is moved to the straight position in which the pivots of the link 62 are substantiallyalined vwith the axis of the rock shaft 15, and the type basket is in its elevated or lower case position corresponding to the position shown from the left in Fig. 1. A spring" 66 connects a forwardly projecting arm 67 on the lever 6l with a fixed. part and passes over the axis 15 when the lever 61 swings to shift the type j basket and resiliently tends to retain the basket in either shifted position.

Means are also provided for guiding the type basket in its shift movements and cooperating with the toggles previously Adescribed for resiliently slowing up or stopping its movement toward either shift position. To this end, a resilient arm 71 is secured to a bracket on the frame of the machine and extends forwardly and upwardly therefrom in a plane substantially perpendicular to the path in which the type basket moves. It will be understood that two of Athe arms' 71 are provided, one at each side of the type basket, although only one of them Vis shown in the drawings. At its forward end, the arm 71 is provided with an opening in which a rod or bolt 72 is arranged. The bolt 72 is mounted in a bracket 73 on-the type basket frame and depends downwardly and forwardly ltherefrom in a plane substantially parallel with the path in which the type basket moves.

Fixedly mounted on the lower end of the bolt 72 is a, stop 74 which normally engages the finger 71 when the type basket is in the normal lower case position shown in Fig. 1. If desired, a sound deadening cushion 75 of fibrousl material, such as felt, may be arranged on the stopl to engage the arm. In order that the stop may be arranged in position to engage the arm 71 at the time when the basket approaches the limit of its upward movement and the lower type is properly positioned lwith respect to the printing' point on the platen, means are provided for adjusting the bolt axially and with it the stop 74.

4To this end, thebolt is threaded in a tapped opening in the bracket 73 and adapted to be turned in one direction or the other by means of a suitable tool to move-it axially in the bracket. A lock nut 76 is threaded on the upper end of the bolt into engagement with the bracket 73 to secure the bolt .in adjusted position. A second stop 77 in the form of a nut is threaded on the boltl to be adjustable thereon between the stop.

74 and the bracket 73. .The stop 77 is locked in adjusted position by means of a lock nut 78 threaded on the bolt in engagement therewith. The stop 77 is so adjusted on the bolt thatuit, or a sound deadening, cushion arranged thereon, moves into engagement with the arm 71 as the type basket approaches the limit of its downward `movement and when the upper type 5 is in position to engage the printing point on the platen.

It will be noted that by this arrangement, the.

stops 74 and 77 can be adjusted to so position the type basket in either case position that the types are properly alined with the printing point on the platen, even thoughI the bearings of the parts of the toggles become worn.

In machines of this kind having a cylindrical platen, the types are made concave to correspond to the curvature of the platen with which they cooperate. It is therefore essential that the types strike jthe platen in such position that the radius of curvature of the types is in'alinement with the radius of curvature of the surface of the platen, in order that a fulliclear type impression be made on the work sheet. Means are therefore provided for adjusting the type basket relatively to the printing point so that the concave types may fully register with the convex surface of the platen throughout their entire areas. To this end, the brackets 13 and 64 in which the

links

12 and 62 are pivoted have bearings on Atrunnions 8l provided therefor on the type basket. Each of the brackets projects both above and below the trunnion and is secured to the type basket at its ends by means of headed

screws

82 and 83 arranged in openings in the type basket'frame and projecting rearwardly `therefrom on opposite sides of the trunnion 81. The bracket is provided with openings adjacent-its upper and lower ends, whereby it is arranged on the 'screws 82 and 83 and its bearing 8l and secured'in such position by means of nuts threaded on the rear ends of the screws.

Guide members

84 and 85 project rearwardly from the typev basket frame adjacent the trunnion Bland engage the bracket to prevent lateral play between it and the basket. VBy this arrangement, the type basket is free from the endsl of the bracket and by turning one of the screws in one direction 1 and the other in the reverse direction, the relation of .the -type basket to the bracket v13 and the center of curvature of the platen may be varied. Since this adjustment is very small, the springs or arms 6 and 7 readily accommodate l themselves to it. It will be noted that when the parts are in the normal Fig. 1 position, the pivots of the link 12 arein substantial alinement with the axis of the bell crank 14 so that its distance from the axis is substantially fixed. This ad- 120 justment of the bracket,` however, also affects its upper case position 'or the position it occupies when the toggle 17, 18 is straight. Means are therefore provided for adjusting the lever 17 on its axis to vary the shift movement o f the basket 1 so that the upper case types properly engage the.

platen when the basket is shifted to.the upper case position shown in Fig. 2. To 'this end, the pivot 17' for the toggle lever 17 may be eccentrically mounted on the frame, as shown, to permit of a limited adjustment of the axial center of the toggle lever whereby the distance through which the'basket is shifted may be varied.

Referring now particularly to the construction shown in Figs. '1, a and 9, the type basket 101 135` is mounted on the free ends of

resilient arms

102 and 103 projecting forwardly from

brackets

104 and 105 projecting upwardly from the frame member 1. The

arms

102 and 103 and

brackets

104 and 105 are so constructed and arranged that L40 about an axis at a greater distance to the rear 15C of the type`basket than the axis of the arms 102. In the arrangement illustrated, the forceV which moves the type basket operates in a d i- -rectionl tangent to the curved paths described by the forward ends of the resilient arms. In the device illustrated in Figs. I to 6 of the drawings, the type basket moves through this point y of tangency when shifted, and since the path of movement is short and the effect of the curvature of its path is split or bisected, so to speak, tl'ige parts lof the type basket in shifted position occupy substantially the same relative positions as when in the normal position, except that they are farther from the printing point on the platen.

v'I and 8 of the drawings, it will` be noted that this component movement is downwardly and -rearwardly in a curved path from its normal or lower case position, but owing to' the shorter radius of movement of its lower endsaid lower end tends to move rearwardly slightly more rapidly than other] parts of the basket, so that it comes to rest in upper case position as shown in. Fig. 8, when shifted from the lower case position shown in Fig. 7. The result of this movement is to bring the normal inoperative position of the type bars nearer to the printing point, so that when actuated they swing through a shorter arc and strike the platenv or the work sheet thereon with a heavier blow, or before it has an opportunity to slow up at the end of its movement. By varying the relative lengths of the

resilient arms

102 and 103, the arc through whichv the type bar swings to engage the platen y Amay be varied withincertain limits.

By a comparison of Figs. 7 and 8 it will-be noted that the angular position of\the type4 bar relative to the printing point on the platen changes when the type basket is shifted, with` the result that with a type bar such as shown in Fig. 6 and having the faces of its type arranged in substantially the same plane, one of the types would strike the platen yon its edge and fail to make a clear impression on the work sheet when the type basket was in one of its shifted positions. In Fig. 9, atype bar is shown in which one-of the types 106, -the upper case in this instance, is inclined relatively to the type bar or other type so that its face fully engages the surface of the. platen when moved to the printing point.

When the basket is shifted to the upper case position from the Fig. 7'position to that shown in Fig. 8, or to the dotted line position, the parts of the basket move along the arcs indicated in broken lines, which causes the basket to swing rearwardly, but since the'arm 102 is shorter than t. the arm 103, its forward end describes an arc of greater curvature than the forward end of the arm 103 Which-causesv the lower end ofthe basket to swing rearwardly to a greater extent than .the part to which the forward end of the arm 103 is secured. This causes the upper end ofv the basket to swing Aless rapidly, and parts of the basket'when in one position are slightly inclined relatively to their positions when in the ""-fothershifted position; asia'result, the types move towardv the platen and if`V thefaces of the types on the type bar are in parallel planes or the same plane, one or the other would noty make a perfect impression, and .for thisreason thev face of one of the types on the type bar is ini clined relatively to the face of the 'other type. In'a construction such as shown yin Figs. 1V to 5, the parts of the basketare arranged in substantially parallel planes in either shifted position, and the faces of the typesare in the same plane or parallel planes. Due to the normal curvature of the arms 6 and '7, when the basket is shifted from the full line to the dotted line position shown in Fig. 1, it moves forwardly during the first half' of its movement and an equal distance rearwardly during the secondhalf of its movement, so that it comes to rest in either position with lits parts arranged in planes substantially parallel with the planes in which said parts are arrangedfwhen the basket isin its other position and at the same distance from the platen. 'I'he means for moving the basket and controlling the extent of movement may be the same for the modification shown in Figs. 7 and 8 as for that shown in Figs. 1 to 5.

Although only two embodiments of the ini vention are shown and'described herein, it will be understood y that this application-is intended to cover such other changes. or modifications as come within the spirit of the invention 'or scope of the following claims.j

We claim:

1, Ina typewriting machine, thecombination of`a frame, a platen, a type'basket, a type b ar movably mounted in said type basket, upper and lower case types on said ,typ bar, means for shiftably supporting the type basket on the frame, a bell crank mounted in the frame, means operatively connecting one arm of said bell'crank with the type basket,\ a lever pivoted on the frame, a link pivotallyvconnected at one end to said lever and at its other endfto the other arm yof said bell/crank and ,lhaving .its pivots in' substantial alinement with the `pivot of the lever whenv the type basket is in one shift position and out of such alinement when the vbasket is in another shift position, and -key controlled means for swinging said leverinone direction or th other to shift the type basket from one case position to another.

2. In a typewriting machinefthe combination ofa frame, a platen, "a type basket, a type bar movably mounted in said type basket, upper and lower case typeson said type bar, means for shiftably supporting. the type basket on the frame, a bell crank mounted in the frame, means operatively connecting one arm of said bell crank with the type basket, a lever pivoted on lthe frame, a resilient stop for limiting the movement of said lever in one direction, a link lpivoted at its ends to the free end of said lever and the other arm' of said bell crank and having its pivots in substantial alinement with the pivot of said lever when the lever engages said resilient` stop, and key controlled means for swinging said lever in one direction or the other to shift the type basket from one case position to another.

3. I a typewritingv machine, the combination of a frame, a platen, a type basket, a type bar movably mountedin said type basket, upper and low,- er case types on said type bar,\mean's for shiftably supporting the type basket on thel frame,` 7-

a bell crank mounted in the frame, means operatively connecting one arm of said bell crank with the type basket, a lever pivoted on the frame, a link pivoted at its ends to the free end of said lever and the other arm of said bell crank,` key controlled means for swinging said lever in one direction or the other to move the pivots of said link to and from a position of substantial alinement with the pivot of said lever to shift the basket to and from one case position, and means for adjusting the lever to vary the extent of movement of the basket required for shifting it to and from said case position.

4. I'n a typewriting machine, the combination of a frame, a platen, a-type basket, a ltype bar mounted in said type basketpand movable into engagement .with the platen, upper and lower case types on said type bar, arms on which said type basket is carried, said arms being of unequal lengths so that they swing the type basket in a curved path to shorten the path of movemen-t of the type bar when the basket is moved to one case position, and means for moving the type basket to shift it from one case position to another.

5. In a typewriting machine, the combination of a frame; a, platen, a type basket, a type bar mounted in said type basket and movable into engagement with the platen, upper and lower case types on said type bar, resilient arms on which said type basket is carried normally tendtype bar mounted in said type basket and mov-v able into engagement with the platen, upper and lower case types on said type bar, arms of unequal length on which said type basket is carried and operative to swing the type basket to shortenv the path of movement of the type bar when the type basket is moved to one case position, the faces of said types being relatively inclined to fully engage the printing point on the platen in either case position, and means fo shifting the basket.

7. In a typewriting machine, the combination of a frame, a platen, a type basket, a type bar movably mounted in said type basket, upper and lower case types on saidtyp'e bar, means for shiftably supporting the type basket on the frame,

-means for shifting the type basket to and from either case position,y said means comprising `a bell crank lever, a link connecting one. arm of said bell crank with the-type basket and movable to and from alinement therewith, an actuating lever pivoted on the frame, a second link connecting said actuating lever with the other ing to the curvature of the platen, a plurality of resilient arms on which the type basket is` carried, a bracket to which said type basket is secured, and means for adjusting the type basket on said bracket against the resiliencyoi' said arms to move the type relatively to the platen when in the printing position so that its lradius of curvature is in substantial radial alinement with the radius of the platen.

RUSSELL G. THOMPSON.

CHESTER W. C RUMRINE.