US2155997A - Typewriting machine - Google Patents

Description

April 1959-v I G. H. STERLING 2,155,997

TYPEWRITING MACHINE Filed June 30, 1937 4 Sheets-Sheet l INVENTORV GORDON H STERL/NG TTORNEY April 25, 1939- Q G. H. STERLING TYPEWRITING MACHINE 0 m f m g m I I INVENTOR (\\\\\\\\\\\\\m ATTORNEY (n N April 25, 1939. e. H. STERLING TYPEWRITING MACHINE Filed June 30, 1957 4 Sheets-Sheet 3 INVENTOR GORDON H. STERLING A TOR NEY Patented Apr. 25, 1939 'JP'ATENT OFFICE TYPEWBITING MACHINE Gordon H. Sterling, West Hartford, Conn., assignor to Underwood Elliott Fisher Company, Chi cago, 111., a corporation of Delaware Application June 30, 1937, Serial No. 151,143

3 Claims.

This invention relates to typewriting machines and with respect to certain more specific features thereof to the devices employed therein for, controlling the carriage in its letter feed escapement, and the ribbon guiding means in its movement toward and from the printing point to intermittently present one or another of the ribbon fields in position for engagement by the type bar.

Although the invention has particular adaptation to power-driven typewriters, it will be obvious that in certain of its aspects it is applicable to manually operated typewriters.

In typewriters employing a source of power such as an electric motor for advancing any keyselected type character to the platen it is desirable to impose on the power as many of the machine operations or actions as possible. In furtherance of this aimsuch actions as the letter- 20 feed escapement and ribbon vibration are desirably thrown over to the power control of the machine thus leaving the operator with only the light task of selecting the appropriate keys and by short, easy depressions of these keys coupling the power agency to do the remainder of the work. a

It is, however, another important consideration that the entire machine in its operation should be as quiet as possible, and difficulty has arisen in the employment of a continuously operated power drive, which is periodically called into action to perform the various functions of the machine, in that to obtain sufficient speed there is considerable abruptness in the power engagement with consequent shock vibration and noise.

It is an important object of the present invention to reduce the shock vibration and noise to a minimum and yet preserve the absolutely ac- 40 curate timing of the machine with respect to the letter-feed escapement, theribbon shifting and the printing movement of the type bar.

In power-driven typewriters the present day tendency is toward standardization on a constantly driven drive-roller which in one fashion or another has momentarily connected to it by depression of a key at the keyboard a. lever or actuator which is in turn connected to operate the type bar or other part of the machine. Preferably, in the present invention, the operation of the escapement and ribbon vibrator iseflected by these levers or actuators through the medium of.a, universal bar connected both tothe escapement and to the ribbon vibrator. A more speciflc form of power drive is a. toothed drive roller to which actuators having pawls are momentarily connected by depression of the keys. Such actuators are picked up abruptly and thrown with considerable force to their extremes of movement and where, as in the present case, these parts and their movement are depended upon to operate the universal bar it is necessary to provide some means by which the shock and noise of impact may be minimized. Laminating the universal bar and pivoting the same on an 1 axis at some distance from its point of contact by the actuator has resulted in considerably reducingthe shock and noise, but some difiiculty has been experienced in maintaining a correct timing of the movements of. the escapement, ribbon vibrator and typeaction owing to the fact that the power-driven actuators are ordinarily coupled at one end through a series of links and levers to the type bars respectively and, there'- fore, these actuators depend for their normal positions on the positions of the various typebars asthey lie at rest away from the printing point. By the present invention it is possible to secure excellent results in respect toaccurate timing and yet. employ a single laminated unlversal bar pivoted and engaged as'aforesaid. It appears, furthermore, that by the present invention the noise and shock of impact is further ized adjustment of the bar in respect to each particular actuator, preferably, as in the present case, by a mere bending of the tooth toward or fromthe actuator to obtain as a. result a prop erlytimed movement of the letter-feed escapement and the ribbon .vibrator with respect to the movement of the type bar. Furthermore the invention provides for including the operation of letter-spacing without printing, under control of the power drive and through the medium of the same toothed universal bar.

Other objects of the invention will be in part obvious and in part pointed out particularly hereinafter. In the accompanying drawings wherein is shown one of various possible embodiments of the invention: j

Fig. 1 is a view in top plan of a power-driven typewriter embodying the invention.

Fig. 2 is a fore-and-aft section of the typewriter shown in Fig. 1.

Fig. 3 is a view in skeleton perspective showing the escapement, ribbon vibrator and controlling devices therefor.

Fig. 4 is a detail view of the field-changing mechanism of the ribbon control.

Fig. 5 is a plan view of the field-changing mechanism shown in Fig; 4 with certain parts in section.

Fig. 6 is a bottom plan view of. the universal bar and its mounting.

Fig. 7 is an end view of the universal bar shown in Fig. 6.

Fig. 8 is a transverse section through the universal bar, the view being enlarged over actual size in order to more clearly show the construction.

Fig. 9 is a view in left side elevation partly in section to more clearly show the working parts of the invention.

The machine comprises a frame having left and right side walls 2| and 22 joined by a front cross bar 23 and at the rear by a rear wall 24. A backbone 25 and a cross bar 26 extendfrom one side wall of the machine to the other.

The backbone 25 has an upwardly extending flange 21, a rearwardly extending flange 28 and a downwardly extending flange 30. The last said flange defines a right angle shoulder with the body of the cross bar and in the final construction of the bar a circular gang cutter is run into the bar from the rear producing a multiplicity of spaced slots 3|. The peripheries of the gang cutter are entered into the backbone to an extent sufllcient to pass through the shoulder defined by the body of the bar and the flange 30 so that the bar, as finally formed, has its flanges 21 and 28 comb-slotted, and spaced openings are produced at the shoulder provided by the flange 3D.

A standard 4-bank keyboard is indicated at 32' comprising type character keys, one of which is indicated at 33, and also carriage shift and return keys, back space and margin release keys and a tabulator bar 34. Each of the type character keys 33 has its associated key lever 35 extending to the upper flange 21 of the backbone 25 with its end in the slot 3| where it is pivoted on a pin 36 extending transversely through the flange 21.

A space bar 31 is located at the front of the keyboard on the opposite side arms 38 and 40 which in turn arefixed on a shaft 4| which is suitably journaled in the opposite side walls of the machine. Arm 38 has a laterally extending pin 42 engaging in a slot 43 of a lever 44 which has its rear end located in one of the slots 3| in the backbone and pivoted, as in thecase of the character levers, on pin 36.

An actuator 45 is arranged in each slot 3|, thus presenting all of the actuators in a row parallel with a drive element 46 which, in this present .preferred form of the invention, is in the shape of a toothed or. flute'd roller journaled in @1350- site side walls-of the machine and driven through a shaft 41 from anelectri'c motor indicated generally at 48. Each actuator is slotted near its upper end as indicated at 50. Through theslots .a pivot pin 5| passes and is held in flange 28; of the backbone'i Thus the actuators are located for. a limited movement inthe, slots 3| bythe pin and slot connection 5||5|. The actuators extend downwardly through the slots 3| and are shaped with a front edge which normally lies actuator toward the drive roller 46.

toward the depending flange 30 of the backbone. To yieldingly receive the actuators against this flange a fine wire coil spring 52 is located in a shoulder cut in the rear of flange 30 and a plate wardly following engagement with the .power-,

drive element. The arms 54 have their rear edges tapered at 56 so -as to facilitate entry of the arms between balls 51 of a crowder lock. A'lug 53 on each actuator just above its arm 54 is adapted'to take a position between the balls of the crowder look after the actuator has been projected downwardly and thus prevent entry of any other actuator until the one originally projected has been returned.

To move the actuators '45 into engagement with the drive roller 46 each of the type character levers 35 and the space bar lever 44 is provided with a dog-carrying arm 60 having a dog 5| pivotedthereon at 62 and held in normally horizontal position by a spring 63 connecting a forward end of the dog with a lug 54 on the armifl. The rear end or nose 65 of dog 6| projects through one of the openings 66 formed where the circular gang cutter intercepted the right angle shoulder of the backbone and cut a series of openings in the front of flange 30. Thus the dogs enter the slots 3| in line with actuators 45 and as any key is depressed the dogs are advanced to move the Each actuator carries a pivoted pawl 61 having two teeth 68 one of which hangs normally in position to be engaged by teeth of roller 46 and when so engaged the pawl 61 will swing around its pivot to lead the second tooth on the pawl into engagement with the following tooth of drive roller 46, thereupon the pawl 61 reachesthe limt of its pivotal movement on the actuator and is moved downwardly carrying the actuator downwardly until a cam edge 10 of the actuator engages an adjustable throw-01f screw H on cross bar 26.

The upper end of the actuator is connected by links 'l2'with actuating levers 13 of a noiseless type action indicated generally at 14. The type bars of the type action are arranged in an are as clearly shown in 'Fig. 1. The actuators are arranged in a straight row, as previously stated, and compensation is made by varying the links 12 as to length or position, or both. Sprifigs 55 return the actuators to their normal position as soon as this'return is permitted by the positions of the type action and as the actuator returns upwardly, if the operators finger has not been removed from the operated key, a shoulder 15 on the actuator will pick up the nose of dog 6| and swing it around the dog pivot against the oppo- I lever has a spring 11 ,Which connects it to an adjustable anchor plate l8 extending transversely of the machine. c

. 70 A stop bar extending between the side walls of the machine limits the downward movement of key levers 35 so that the dogs 5| will be advanced just sufliciently to insure the engagement of the actuators with the drive roller '46. The 7 space bar 31 is also limited in its depression movement by a stop flange III on arm 40 engaging an adjustable stop 02 in a bracket 83 secured to side wall 22 of the frame. Thus the space bar lever 44' is limited in its-pivotal movement so. that its dog 6| will cause suitable engagement of its corresponding actuator with the drive roller 46.

The escapement and ribbon vibrating mechanism will now be described. The cross bar 26 which carries at its forward side the crowder lock mechanism including theballs 51 is provided with rearwardly extending ears 84 and 85 'at opposite sides of the machine. These ears carry pivot screws 86 which are adjusted to engage in conical recesses in the .end of a shaft 81. Rolled around this shaft and suitably secured thereto as by welding at spaced points is one side 88 of an otherwise substantially flat universal plate or bar 90. This'bar is constructed of at least two plies of thin material, preferably metal, as shown clearly in Fig. 8 of the drawings, the upper ply being indicated at- 9| and the lower ply at 92..

These thin metal plies or strips are spot welded together to produce a laminated bar which will absorb vibrations incident to the impact of the actuators with the bar. Preferably, I employ a rather wide bar and so arrange the bar with respect to the actuators that the latter contact with the former along themargin of the bar remote from the pivot.

According to the present invention the pivoted bar 90 laminated or unlaminated, as the case may be, is provided with spaced slots of suitable depth along its forwardmargin, as indicated at 93, thus providing a series of spaced teeth, one

for every actuator, underlying the same in posi-.

tion to be engaged thereby as the actuator is thrown by its engagement with the drive shaft.

The bar is of sufhciently thick and strong stock to prevent deformation of the teeth from engagement by the actuators, but on the other hand is sufllciently workable so that the teeth may be bent individually out of the plane of the bar in either direction, thereby suiting the bar to the position which each actuator assumes as a result of its connected type bar coming to the rest position. Provision is thus made for localized adjust-- ment of the type bar to suit the conditions existing along the row of actuators.

The universal bar 90 is normally held in the position shown in Fig. 2, with its forward margin underlying the slots of a comb-slotted plate 59, by a torsion spring 94 shown in Fig. 3. Thus the universal bar underlies any key-selected actuator prior to the downward movement of the actuator by the power-drive member 46. As the actuator is moved downwardly it picks up the universalbar by one of its teeth and swings the bar around its pivot 86 in opposition to the spring 94 until the cam edge 10 engages throw-off screw H and the actuatoris thus urged forwardly to escape the universal bar. :Therefore, in every instance of a selection and power actuation of a type bar, or movement of the space bar lever, followed by a power actuation of an actuator, the universal bar 90 is struck by an actuator and rocked. It is,

. however, almost immediately released to the action of its return spring 94 which restores it to normal position against a cushion 69 on the under side of plate '59.

At the end of the universal bar pronmate the 7 side wall 22 the bar has secured to it an arm 95 which arm is connected pivotally to a link 96 which in turn connects to a lever 91 pivoted at 98 to a bracket 99 which latter is supported in fixed relation to the frame. Lever 91 has its opposite end provided with a headed stud I upon the shank of which there is loosely articulated an arm IOI having at its upper end an angular projection I02.with a forwardly extending pin,

I03. The pin I03 passes forwardly through a curved slot I04 in an arm I05 fixed to the end of a shaft I06 suitably journaled in fixed relationwith provision for.relatively slight movement about a horizontal axis. An operating finger piece II6 projects through the frame of the machine into position to be manipulated by the operator. The slot I04 of arm I05 is substantially on a radius from the stud I00, thus providing for movement of the arm IOI with-the pin I03 riding through the slot Midway of the slot I 04 itienup and down movement of pin I03 without rocking the arm I05. This is aneutral or stencil position of the ribbon-vibrator mechanism. In either extreme position of the pin I03 in slot- I 04 the I arm I05 is rocked each time the universal bar is depressed by an actuator'and the depression of the universal bar straightens a toggle involving the links 95--96 which transmits movement through lever 91 and arm IM to pin I 03. In ac cordance with the distance of.the pin I03 from the axis of movement'of arm I05 there will be a greater or lesser rocking movement of arm I 05 and a corresponding difference in angle to rotative movement of shaft I06.

At the rear of shaft I06 there is an arm I I8 which is connected by a link I with an ear I2I on a. bell crank lever I22 pivoted at I23 on a bracket I24 secured to a cross bar I25 of the frame. Lever I22 carries a stud I26 the shank of which rides in a slot I21 in bracket arm I24. A ribbon guide is indicated in Fig. 3 at I28. It is of substantially U formation and at its right stem at red field or stripe I36. The ribbon is suitably reeved through the ribbon guide I29 for passage larges in an up and down direction providing for The other end of link therethrough in a lengthwise direction under con trol of the ribbon 'feed mechanism and it is supported for movement by the guide to elevate-one or the other of the fields into position opposite the printing line at each actuation of the ribbon vibrator mechanism. If the pin I03 is at theright extreme of slot I04 the same amount of downward pull of pin I03 will give a correspondingly greater angle of movement of shaft I06 than is obtained when the pin I03 is at the'left extreme of slot I04.

Thus the ribbon I35 will be elevated 51 greater distance when the pin I03 is at the right extreme. and the red field of the ribbon will be presented to the .printing line upon each actuation of the universal bar.

About midway oflthe length of the universal bar an angle bracket I31 is secured to the bar and 15 an upstanding arm I38 of this bracket is pivotally connected to a pull rod I40. The rear end of the pull rod projects through an eye I4I of a rocker frame I42 which has its opposite ends engaged by swinging movement a distance corresponding to the distance between teeth I4'I of an escapement wheel I48 which is rotatively mounted in a plate I50 secured to a cross bar I5I. A shaft I52 has a splined connection with the escapement wheel I48 and extends upwardly to a suitable journal bearing I53 which in turn is secured to a carriage track I54. Within the track a carriage rail I55 is mounted for endwise movement on anti-friction bearings and secured to the track is a car-.

riage rack I56 in engagement with a pinion I51 on the upper end of shaft I52. Thus for each step of escapement of the wheel I48 the rack I56 is permitted to escape one step of movement under the influence of the usual carriage spring. The rail I55 is secured to opposite end frames I58 of a carriage which includes a roller platen I60.

The rocker frame I42 at the rear of the machine has a forward obliquely extending arm I6I upon the end of which there is pivotally mounted a holding dog I62. Normally this dog is in engagement with a flat face of one of the teeth I41 of escapement wheel I48. A coil spring I63 connects a tail I64 of dog I62 with a tail I65 of dog I46. As the rocker frame I42 is rocked by the engagement of an actuator with the universal bar bothdogs I46 and I62 are moved upwardly, the stepping dog I46 entering between two successive teeth ofthe escapement wheelv and the holding dog I62 eventually moving out of its position of holding engagement with the first of these teeth. This releases the escapement wheel to the control of dog I46 which'permits a single tooth escapement of the wheel during which spring I63 is stressed. After the actuator has passed beyond the universal bar, the bar is returned and the rocker frame is moved in the reverse direction,

which enters the holding dog into position against the next tooth of the escapementand moves the dog I46 out of engagement with the wheeLwhereupon its spring I63 returns it to its original position where it is adapted to engage between the next teeth of the escapement wheel upon subsequent movement of the universal bar.- Thus on every power actuation of the type barthe letter feed escapement is let off one step prior to the time bar reaching the printing point.

It will be noted that owing to the toggle straightening action of arm and link 06 the movement upward of the ribbon vibrator will be at first speedy followed by deceleration and a substantial dwell at its upper extreme. This provides a very desirable action in that the ribbon, when at the printing line and engaged by the type, is substantially without movement so that the liability of blurred write is obviated.

Desirably the platen carriage is mounted on pairs of upstanding flat springs at opposite sides of the machine which bias the carriage so that a rail I66 thereof is constantly urged rearwardly against a plate I61 on an upstanding arm I66 of a center tie I10.

From the foregoing it will be apparent that a universal bar is provided for controlling the ribbon vibrator and escapement mechanism of a typewriter which bar has its resonance reduced by the formation of individual teeth remote from the pivotal axis of the bar and taking the blows of the actuators, and which bar has provision for localized adjustment to suit it to the position or movement of each actuator. Thus by a very simple and inexpensive device the extremely important timing between the type bar, escapement and ribbon vibrator of the machine may be obtained.

What is claimed is:

1. In a power-driven typewriter, a power-drive element, a plurality of selectively operable actuators arranged in a row parallel to said drive element, a comb-slotted member adapted to receive the actuators respectively in the slots and a universal plate mounted for pivotal movement on an axis parallel with the drive member and normally spring-held in position against said comb-slotted member so as to underlie the slots, said plate having bendable teeth which underlie the slots and are adapted to be engaged by the actuators as they are selectively engaged with the power-drive element. 7 I

2. In a power-driven typewriter, a power-drive element, a transverse comb-slotted member, a plurality of selectively operable actuators having their ends respectively located slidably in the comb-slots, in a row parallel to said drive element, and a member mounted for pivotal movement on an axis parallel with the drive member and springheld with its free margin adapted to intercept said actuators, said member having bendable teeth along its free margin which teeth lie opposite the comb-slots to intercept respectively the actuators in their selective operation.

3. In a power-driven typewriter, a. power-drive element, a transverse comb-slotted member, a plurality of selectively operable actuators having their ends respectively located slidably in the comb-slots, means movably mounting said actuators in a row parallel to said driveelement, a member mounted for pivotal movement on an axis parallelwith the drive member and spring-held with its free margin adapted to intercept said actuators, said member having bendable teeth along the .free margin which teeth bridge the comb-slots respectively, means for disconnecting said actuators from said power-drive element after they have actuated the pivoted member and means for returning said actuators to position for subsequent engagement by the power-drive element and repeat operation of the pivoted member.

GORDON H. STERLING.

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