US2648418A

US2648418A - Variable escapement for typewriters

Info

Publication number: US2648418A
Application number: US91126A
Authority: US
Inventors: Frederick W Schremp
Original assignee: Remington Rand Inc
Current assignee: Remington Rand Inc
Priority date: 1949-05-03
Filing date: 1949-05-03
Publication date: 1953-08-11
Anticipated expiration: 1970-08-11

Description

Aug. 11, 1953 F. w. SCHREMP VARIABLE ESCAPEMENT FOR TYPEWRITERS 4 Sheets-Sheet 1 INVENZTZOR r 5c 2' 222 ,Fee r 2 I j p I TT ORNEY- Filed May 3, 1949 S i FE mw.

Aug. 11, 1953 F. w. SCHREMP 2,648,418

VARIABLE ESCAPEMENT FOR TYPEWRITERS Filed May 3, 1949 4 Sheets-Sheet 2 INVENTOR 1.953 F. w. SCHR EMP 2,648,418

VARIABLE ESCAPEMENT I FOR TYPEWRITERS Filed May 3, 1949 4 Sheets-Sheet 3 INVENTOR Aug. 11, 1953 F. w. sHREMP VARIABLE ESCAPEMENT FOR TYPEWRITERS 4 Sheets-Sheet 4 Filed May 3, 1949 INVENTOR flederzcii r 6222? 4"? ATORNEY Patented Aug. 11, 1953 VARIABLE ESCAPEMEN T FOR TYPEWRITERS Frederick W. Schremp, Elmira, N. Y., assignor to Remington Rand Inc., New York, N. Y., a corporation of Delaware Application May 3, 1949, Serial No. 91,126

Claims. (Cl. 197-84) This invention relates to variable escapement mechanism for typewriters.

The invention provides a variable escapement mechanism particularly adapted to obtain a duplex escapement operation of a kind suitable for use in writing languages such as Arabic and Burmese. According to the invention, the variable escapement is provided by mounting a pivoted stop on the escapement rocker for movement into and out of an operative position to limit the movement of the loose dog for producing a different stroke of operation of the loose dog to that obtained by the fixed stops on the escapement rocker; by increasing the number of teeth on the escapement wheel for cooperation with the pivoted and fixed stops on the rocker; and by providing a supplemental universal bar selectively operated by selected type actions for moving the pivoted stop into operative position to produce the difierent letter spacing operation of the carriage to that produced by the fixed stops. In this way, two different letter spacing movements of the carriage can be obtained through the use of a single pivoted stop on the escapement rocker actuated by the supplemental universal bar so as to modify the usual operation of the typewriter escapement mechanism by the type actuated universal bar. The escapement mechanism is also constructed to obtain a letter spacing operation of the carriage in either direction, the left to right carriage movement being obtained by adding a bracket rotatably mounting a pinion intermeshed with the escapement gear and the carriage rack bar to obtain the reverse movement required for writing Arabic and some other languages.

In the drawings:

Fig. 1 shows a vertical transverse section through a typewriter diagrammatically illustrating a center type action with the mechanism applied thereto according to the invention, to produce the two different letter spacing movements of the carriage.

Fig. 1a shows the forward ends of the key levers and space bar mechanism, offset above Fig. 1, which are omitted from the left-hand side of Fig. 1 and which complete the cross-section through the typewriter.

Fig. 2 is an enlarged vertical cross-section taken on line 2-2 of Fig. 1 showing the escapement mechanism and associated portions of the typewriter on a scale twice the normal size.

Fig. 3 is a vertical cross-section taken approximately on the line 3--3 of Fig. 2 illustrating the escapement rocker in the position of rest between letter spacing operations of the escapement.

Fig. 4 is a cross-section similar to Fig. 3 showing the escapement rocker at the opposite limit of its pivotal movement during a spacing operation, the pivoted stop being shown in an inoperative position in full lines and in an operative position in dot and dash lines.

Fig. 5 is a fragmentary perspective showing a few of the key levers and part of the case shift mechanism at the front of the typewriter in perspective looking from a position above and to the right of the machine with the frame and other portions removed, for illustrating the mounting of the supplemental universal bar and the key lever actuated members having selective cooperation with the universal bar in operating the pivoted stop mounted on the escapement rocker.

The invention is described and shown in the drawings as applied to a Remington typewriter more specifically known as the Model 17 or Remington KMC. This typewriter is shown in Patents Nos. 2,289,531, July 14, 1942; 2,304,216, December 8, 1942; 2,326,312, August 10, 1943; and in U. S. application S. N. 66,672, filed December 22, 1948, now Patent No. 2,579,763, in view of which only those portions of a typewriter are illustrated as are necessary to show the invention in association with related typewriter parts. The invention is designed to provide for the replacement of a few parts of the conventional typewriter with the addition of new parts for obtaining a duplex escapement with the usual carriage feed or with a reverse carriage feed for the purpose of writing such languages as Burmese and Arabic.

The conventional Remington typewriter has the usual frame, only portions of which are illustrated in the drawings. The back plate of the frame is illustrated at l and a front lower cross bar at 2. The transversely extending key lever bracket 3 is secured to the frame and pivotally mounts the rear end of each key lever 6 while the front end extends into the keyboard of the typewriter where it carries key cap 5. A transversely extending bell crank bracket 6 is attached to the frame and pivotally mounts each type bar operating bell crank l pivotally connected at one end by a link 8 with the corresponding key lever 4. Bell crank I has a link 9 connecting the other end with the corresponding type bar i9 pivotally mounted on type segment i I. Type segment i I is mounted for vertical shifting movement in the operation of the case shift mechanism for shifting the type bars in writing upper and lower case letters in the manner described in aforementioned Patent No. 2,289,531.

A bracket I2 is mounted on bell crank bracket 6 and has one end of tension spring l3 attached thereto while the opposite end is connected to key lever 4 as shown in Fig. l. A transversely extending anchor bar l4 has one end of bell crank operating tension spring l5 connected thereto with the opposite end attached to bell crank l, as shown in Fig. 1. Springs [3 and I5 normally return each key lever and type bar to the inoperative position with type bar It engaged on type bar cushion 16.

The platen is indicated at IT in Fig. 1 and each type bar has printing engagement in the central position in a manner well known in the art, the mechanism for supporting the platen including the ribbon guide and type guide construction shown in the aforementioned patents and being omitted in view of their having no direct association with the disclosure of the present invention.

The typewriter has the usual tabulator mechanism mounted on back plate I, including lower comb l8 and upper comb bars l9 mounted for slidably guiding a plurality of blades in spaced parallel relation for vertical movement. The tabulator mechanism is of conventional form and is not illustrated in the present application aside from the comb structure which is used in connection with the new escapement mechanism.

The escapement mechanism has an escapement rocker bracket 23 mounted on rocker bracket supporting plate 2! detachably secured to back plate 6. The escapement wheel assembly has a sleeve carrying escapement wheel 22 rotatably mounted on wheel bearing screw 23. Escapement wheel 22 has twice as many escapement teeth 24 as the usual escapement Wheel. Escapement gear 25 is rigidly mounted on the sleeve carrying escapement wheel 22 adjacent one side, while a friction brake 2B is also mounted on the sleeve or hub of escapement wheel 22 at the opposite side for holding loose dog silencer arm 21. This escapement wheel assembly is rotatably maintained in assembled relation on escapement rocker bracket by wheel bearing screw 23, as shown in the aforementioned application and used on the Remington typewriter. The movement of loose dog silencer arm 21 is limited by step screw 23 having one end engaged in a slot in loose dog silencer arm 27 which provides for sufficient movement of arm 27 to operate the loose dog of the escapement mechanism for holding it in disengaged relation relative to teeth 24 of the escapement wheel in the return movement of the carriage in the usual well-known manner.

Escapement gear 25 may be directly intermeshed with carriage feed rack 29 for normal carriage feed operation. However, in writing Arabic and some other languages, it is necessary t provide for a reverse motion of the carriage from that normallyv used. For this purpose a bearing plate 33 has one end mounted on wheel bearing screw 23 in spaced parallel relation to escapement rocker bracket 20 and the opposite end mounted on bearing plate supporting screw 3| mounted in horizontal relation to wheel bearing screw 23 on escapement rocker bracket 20. Bearing plate 30 carries bearing screw 32 for rotatably mounting reverse pinion 33 intermeshed with the teeth of escapement gear 25 and carriage feed rack 29. This provides a means for reversely feeding the carriage in writing languages, such as Arabic, through the addition of reverse pinion 33 and bearing plate 30 to the usual escapement wheel assembly of the Remington typewriter. The carriage feed rack 29'may 4 be mounted on the carriage in position for either direct intermeshing engagement with the teeth of escapement gear 25, or with the teeth of reverse pinion 33 in the manner shown in Fig. 2.

An escapement rocker 35 is mounted for oscillating movement on rocker bearing screws 34 mounted in arms arranged in spaced parallel relation on escapement rocker bracket 20. Escapement rocker 35 is formed with a fixed stop 33 for limiting movement of loose dog 31 in one direction. Loose dog 31 is pivotally mounted on the upper end of carrying arm 38 pivoted at its lower end on escapement rocker 35. Tension spring 39 has one end attached to loose dog 31 and the opposite end to a stud on rocker 35 and normally moves loose dog carrying arm 38 in a counterclockwise direction and loose dog 31 in a clockwise direction, as shown in Fig. 2, for positioning stepping tooth 43 on the end thereof in the path of movement of teeth 24 on escapement wheel 22. The conventional escapement used in the Remington typewriter usually has another stop means for limiting the counter-clockwise movement of carrying arm 33 in a fixed spaced relation to fixed dog 36 for limiting movement of the loose dog to secure the desired letter spacing operation of escapement wheel 22. In the present invention, this stop means has a substitute which will be hereinafter described. The usual loose dog guide bracket 4! is mounted on the same side of escapement rocker 35 as the loose dog and is constructed in the usual manner to guide loose dog 37 for oscillating movement in a substantially horizontal position.

The invention provides a stop bracket 42 mounted on the opposite side of escapement rocker 35 from loose dog guide bracket 4!. The same screws secure loose dog guide bracket 4i and stop bracket 42 on opposite sides of escapement rocker 35 in the central portion thereof. Stop bracket 42 is formed with a laterallydirected fixed stop projection 43 extending over the upper edge of the central portion of escapement rocker 35 into the path of movement of carrying arm 38 to limit the counter-clockwise movement thereof, as shown in Fig. 2. This fixed stop 43 cooperates with fixed stop 3% to provide a pair of fixed stops for limiting the movement of loose dog 31 in producing a predetermined spacing operation of escapement wheel 22 and a uniform letter spacing movement of the carriage through carriage feed rack 29.

Stop bracket 42 is formed with a lateral projection at the lower left-hand end as shown in Fig. 2 projecting away from escapement rocker 35 to provide a pivot arm 44 mounting pivoted stop 45 on stud 46 carried by arm 44 in a position for pivotal movement in a plane substantially perpendicular to escapement rocker 35. Pivoted stop 45 is pivotally mounted on stop bracket 42 carried by rocker 35 adjacent the lower end thereof while the upper end has a stopiinger 4'! projecting through slot 48 in the upper edge of rocker 35 with the free end projecting beyond the opposite side of the rocker where it is formed with a depending inclined lipportion 49.

The free end of stop finger 4! is positioned to project into the path of movement of tooth 40 on the free end of loose dog 3'! in the operative positionof the pivoted stop for limiting counterclockwise movement of. carrying arm 38 and loose dog 31, as shown in Fig. 2, so that it has a smaller amount of movement than that provided between fixed stops 36 and 43. In this way pivoted stop 45 securesa. smaller. amount ofmovement ofloose dog 31 and a correspondingly smaller amount of movement of escapement wheel 22 and carriage feed rack 29 for producing a smaller letter spacing movement of the carriage.

The central portion of pivoted stop 45 projects outwardly away from escapement rocker 35. A stud is mounted on the central portion of rocker 35, projects laterally therefrom, rotatably mounts roller 56, and is formed to support one end of tension spring 51 secured at the opposite end to lower comb 18. This central portion of pivoted stop 45 also has an operating projection 52 extending laterally from stop 45 in the opposite direction from the stud carryin roller 50. Both roller 56 and operating projection 52 are positioned for engagement by actuating mechanism for moving pivoted stop 45 into operative position against the tension of spring 51 normally maintaining the stop in inoperative position. An arm 53 at the lower end of pivoted stop 45 is positioned to engage the adjacent face of escapement rocker 35 and limit the movement of stop 45 on the escapement rocker in a clockwise direction as shown in Fig. 3. Stop screw 54 limits the oscillating movement of rocker 35 on pivot screws 34 in a clockwise direction as shown in Fig. 3.

A limiting projection 55 on pivoted stop 45 above stud 46 limits the movement of the stop in a counter-clockwise direction, as shown in Fig. 3, by engaging the face of escapement rocker 35 to control the position of pivoted stop 45 relative to escapement rocker 35 so the free end of finger 41 is positioned in the path of movement of the free end of loose dog 31. A tension spring 56 has one end connected to the lower end of escapement rocker 35 and the opposite end connected to laterally extending pivot arm 51 on escapement rocker bracket 20. Tension sprin 56 cooperates with spring 5| in maintainin the escapement rocker and pivoted stop 45 in the normal position of rest between letter spacing operations, as shown in Fig. 3.

Fixed stop 58 is formed by a lateral projection on the upper edge of rocker 35 positioned to engage a tooth on escapement wheel 22 in the operation of the escapement as rocker 35 is moved in a counter-clockwise direction as shown in Fig. 4 for stepping cooperation with the escapement wheel and loose dog 31 in securing both single and double spacing movements of the escapement and carriage.

The typewriter has the usual universal bar 60, Fig. 1, formed with rearwardly extendin arms 61 pivotally connected at the rear ends with type bar universal oscillator arms 62 carried by oscillator shaft 63 rotatably mounted in oscillator bracket 64 secured to type segment I l Universal bar 66 is of curved form and is slidable in type segment 11 in a position to be engaged by each type bar 16 adjacent the pivot mounting thereof on type segment H as the type bar moves into printing poistion against platen 11. This construction and operation of universal bar 60 with oscillator arms 62, oscillator shaft 63, and bracket 64 is the conventional type used in the Remington typewriter hereinabove mentioned and shown in Patent No. 2,326,312.

The rear end of arm 61 is positioned to engage roller 65 on escapement operating bail 66 pivotally mounted on the upwardly extending supporting arm for lower comb I8 at the left-hand end thereof, as shown in Fig. 1. On the opposite side of the pivotal mounting for escapement operating bail 66 from roller 65, the bail is provided with an arm having one end of escapement link 61 pivotally secured thereto while the opposite end extends rearwardly for connection with the escapement rocker. The opposite end is screw threaded for slidably receiving sleeve 68 on the screw threaded end for lengthwise adjustment. Sleeve 68 engages in a slot in the lower edge of escapement rocker 35 in which it is retained by retaining arm 69 secured to the lower edge of the escapement rocker 35 by a retaining screw.

A pair of escapement link adjusting nuts 10 are threaded on the threaded end of escapement link 61 at opposite ends of sleeve 68 and have a size adapted to engage opposite faces of escapement rocker 35 when the end of link 61 is retained in engaged relation with the escapement rocker by arm 69 with sleeve 68 engaged in the notch or recess in the escapement rocker. Sleeve 68- has a length suificient to provide for a limited amount of movement of escapement rocker 35 independent of the operation thereof by universal bar 66. In the normal typing operation each type bar 56 will operate universal bar 60 to secure a complete oscillating movement of escapement rocker 35 for securing a letter spacing operation of the carriage through the cooperation of loose dog 31 and fixed dog 58 with teeth 24 on escapement wheel 22. This operation will be clearly understood from the disclosures in the aforementioned patents and applications.

Accordin to the invention, the escapement rocker is controlled and operated by other means in addition to universal bar 60 in connection with the operation of pivoted stop 45 to secure a different and smaller letter spacing operation of the carriage. For this purpose, mechanism is provided as an attachment to a standard typewriter construction for selectively securing the operation of pivoted stop 45 to selectively produce the different spacing operation thereof in controlling movement of pivoted dog 31 so that a smaller spacing operation is produced for letter spacing movement of the carriage than when pivoted stop 45 is in the inoperative position during operation of the escapement rocker by the universal bar during type bar actuation.

An actuatin slide 15 is slidably mounted for vertical movement in the upper and lower comb assembly carried by back plate I, as shown in Fig. 1. An actuating arm 16 has the center portion pivoted on stud 16' carried by slide 15 arranged so that one end engages under roller 50 on pivoted stop 45. Arm 16 is positioned to operate pivoted stop 45 from its inoperative position of rest between letter spacing operations of the carriage into the operative position in upward sliding movement of actuating slide 15 to secure the operation of pivoted stop 45 in controlling movement of movable dog 31 to produce the different and smaller letter spacing operation of the escapement mechanism.

The opposite end of actuating arm 16 has an aperture 11 engaged over stud 18 on actuating slide 15 having a smaller diameter than aperture 11 to provide for limited pivotal movement of actuating arm 16 on actuating slide 15. Tension spring 19 has one end secured to the end of actuating arm 16 engaged over stud 18, while the opposite end is secured to actuating silde 15 for normally moving actuating arm 16 in a clockwise direction, as shown in Fig. 3, to retain the free end of arm 16 under roller 50 in its uppermost position. This limited movement of pivoted actuating arm 16 on slide 15 provides for having arm 16 follow roller 50 in the operation of bar 83.

the escapement to hold pivoted stop 45 in the operative position in securing a single or half spacing operation of the escapement mechanism in controlling movement of loose dog 31, in a manner that will be hereinafter more fully described. Actuating slide has limited vertical sliding movement governed by the length of recess 80 in the rear edge thereof forming shouldered portions at the top and bottom of the recess for engagement with lower comb l8.

A supplemental universal bar 8|, Figs. 1 and 5, is provided for operating actuating slide 15 and pivoted stop to secure the shorter letter spacing operation of the carriage in the operation of the escapement mechanism through suitable linkage. Supplemental universal bar 8! is formed of a pair of angle bars each having one flange engaged in superimposed relation with the other flange of each angle bar extending laterally from these superimposed portions in spaced parallel horizontal relation to provide upper case selector bar and lower case selector bar 83. Upper case selector bar 82 has the flange transversely slotted to provide a pluralityof forwardly extending fingers 84 equal in number to the number of type actions in the typewriter and arranged so that each finger :84 is adapted for engagement and operation by one of the type actions in a manner that will be hereinafter described.

Laterally extending arms 85 are formed on opposite ends of supplemental universal bar 8| on the angle bar formedwith lower case selector Arms 85 project forwardly and downwardly and are pivotally secured on pivot studs carried by pivot brackets 86 mounted on case shift levers 81. Case shift levers 81 are mounted at opposite sides of the typewriter and are operatedfrom the-keyboard in the usual well-known manner. Case shift levers B! have the rear ends secured toshift lever shaft 88 rotatably mounted mechanism are shown which mount the supplemental universal bar 8| to support it in such a .way, that :it is moved in the operation of the case shift levers 81 for support in both upper and lower case positions, in order that the desired letter spacing operation of the carriagemay be obtained for both upper and lower case positions, in view of some languages having letters :requiring two .or more letter spacing movements of the carriage, difierent from each Other, in Write ing different upper and lowercase letters. In some cases, it is desired to obtain a different letter spacing operation of the carriage in the upper case position from :that produced in the lower case position for a particular type action. The present supplemental universal bar BI i constructed to obtain selective letter spaci s operations of the carriage er t pp r a ow rca le t r as m e con ered es abl or r ra e in wr n ny anguag The caseshift mechanism including levers 8'! is shown in the lowercase position at the upper limit of 'movemcnt'of case shift levers -81 in both Figs. 1 and 5.

A selector mechanism is provided for operating supplem'en'tal universal bar 8| selectively in the operation of a selected type action where single or half space operation of the carriage in letter spacing movement is desired. This selector mechanism has a selector comb 90 mounted on transversely extending frame bar 9| secured at opposite ends to front side portions of the typewriter frame. A pivot rod 92 is mounted in the beaded edge of selector comb 90 for pivotally mounting a plurality of selector levers 93 in the central portions thereof. The lower ends of selector levers 93 are bifurcated to provide a slot running lengthwise of the lower end of the lever to slidably engage over a stud 94 mounted on a key lever 4 of a type action.

Selector levers 93 are provided only for those type actions where it is desired to secure a single spacing operation of the escapement mechanism and a single letter spacing movement of the carriage in either or both the upper or lower case position. Where it is not desired to obtain .supplemental universal bar 8|. In order to provide a mechanism for obtaining at least a duplex escapement mechanism for obtaining two letter spacing movements of the carriage, namely single and double space movements of the carriage, selector comb 90 is constructed to receive and pivotally mount a selector lever for every type action normally used in the typewriter and each key lever 4 is provided with a stud 94, if desired, so that selector levers can be used for those type actions where both single and double spacing movements of the carriage may be desired. These two spacing movements of the carriage herein described may be referred to as half and full letter spacing movements of the carriage and it is therefore to be understood that this invention provides a mechanism for obtaining at least two different spacing movements of the carriage for two different letter spacing operations selectively controlled in the operation of the several type actions.

Key lever 4, as shown in Fig. l, is illustrated in the upper inoperative position, as herein above described, with stud 94 near the upper end ofthe .slot in bifurcated selector lever 93. Stud .94 is located on key lever 4 in a position to the rear of pivot rod 92 and the lower end of the lever extends in angular relation downwardly and rearwardly from pivot rod 92 relative to stud 94 so that as key lever 4 is depressed to operate type bar It for a printing operation, selector lever 93 will be moved in a clockwise direction about ivot rod 92, as shown in Fig. 1. The upper end of each selector lever 93 is formed with an operating foot 95 positioned in rearwardly extending relation to engage the front edges of upper and lower case selector bars 82 and 33 respectively, in the lower case position of the case shift mechanism, as shown in Fig. 1. Lower case selector bar 83 is positioned in the lower case position of the-case shift mechanism to be engaged by all of the selector levers 93 for operating supplemental universal bar 8! for all type actions that are provided with selector levers 93.

It is desirable in writing Arabic to have a single or half space letter spacing operation of the escapement mechanism and carriage for all lower case letters and, therefore, lowercase selector 'bar 83 is formed as a continuous solid flange on supplemental selector bar 8|. Since it is desirable to have some upper case letters in Arabic printed with a single letter spacing operation of the carriage while others require a double letter spacing operation of the carriage, the upper case selector bar is provided with fingers 84 adapted for positioning so that they may have selected engagement with selector levers 93. For those letters requiring the full or double spacing operation of the carriage in letter spacing movement where the lower case letters have the half or single space operation of the carriage, selector fingers M are bent upwardly as indicated at 84' into a position so they will not be engaged by a foot 55 on a selector lever 93 in the operation of a type action in the upper case position.

A bracket 96 is mounted in the central portion of supplemental universal bar 3! and extends above the bar where it is formed with a forwardly extending projection having one end of a supplemental escapement operating link 9? pivotally secured thereto. The rear end of link 91 is pivotally secured to on end of bell crank 98 mounted on tabulator bell crank shaft 99. The opposite end of bell crank 98 extends under slide 15 and carries slide operating screw H09 adjustably mounted therein and having the upper end engaging the lower end of actuating slide 15 for operating pivoted stop 45. A tension spring it)! has one end secured to bell crank 95 and the opposite end secured to retaining plate I 02 mounted on the lower edge of key lever bracket 3 and normally used as a spring anchor and means for retaining key levers A pivotally engaged with the bracket. Tension Spring it! operates to retain bell crank 98 and suppl mental universal bar 8| in the inoperative position ready for operation by a type action to secure a single letter spacing operation of the carriage.

A bar I93, Fig. 1, extends transversely across the frame of the typewriter above supplemental universal bar 8!. A spring stop finger I94 is mounted in the central portion of bar Hi3 and extends downwardly into a position aligned with bracket 96 on supplemental universal bar 8! for limiting the counter-clockwise rotation of supplemental universal bar 8!, as shown in Fig. 1, operating link 97 and bell crank 98 through the operation of spring IOI.

In operating a typewriter equipped with the variable spacing mechanism herein described for producing a single and double spacing operation, an operator actuates the key levers in the usual manner for securing the operation of each type action to move the type bar for printing on the paper on the platen. If a key lever selected to secure a single spacing operation is actuated, stud 94 will operate selector lever 93 associated therewith in a clockwise direction, as shown in Fig. l, in the lower case position for engaging foot 95 with the free edge of lower case selector bar 83. Further movement of key lever 9 to produce a printing operation of the type bar will cause lever 93 to move supplemental universal bar 8| in a clockwise direction as shown in Fig. l and through the linkage mechanism move actuating slide 15 upwardly. This movement will cause pivoted actuating arm 19 to move pivoted stop 45 in a counter-clockwise direction from the position shown in Fig. 3 so that the end of finger 4'! will be moved and retained in alignment with the end of loose dog 31 for limiting its movement in the entire subsequent operation of the escapement for one letter spacing movement of the carriage.

As pivoted stop 45 is moved into the operative position shown in Fig. 3, the movement of actuating slide 15 upwardly will also move escapement rocker 35 in a counter-clockwise direction, as shown in Fig. 3, to a limited extent as actuator slide reaches its upper limit of movement. This is obtained through limiting projection 55 engaging the side of escapement rocker 35 in the movement of pivoted stop t5 into its operative position. This movement tends to disengage loose dog 37 from a tooth on escapement wheel 22 in the stepping operation between loose dog 3'! and fixed dog 58. However, the movement of escapement rocker 35 by operation of supplemental universal bar 8i is not sufiicient to release loose dog 31 from a tooth 24 of escapement wheel 22.

The operated type bar I0 during this operation of actuating slide i5 will move from type bar cushion [6 toward the printing position against the platen. The operation of stop finger 45 and escapement rocker 35 above described through the movement of actuator slide 15 will take place while type bar it] is moving toward the printing position and before it engages the platen in the printing operation. This operation will also take place in advance of the point at which type bar I0 engages universal bar 69. As type bar I9 moves close into printing position against platen i1, it will engage universal bar 30 and operate the usual spacing mechanism of the typewriter which will move escapement rocker 35 in a further counter-clockwise direction into the position shown in Fig. 4. In Fig. 4 loose dog 31 has been disengaged from a tooth 24 and fixed dog 58 has moved into engagement with a tooth 24 in the stepping operation of the dogs. The springs for actuating the escapement rocker will return it to its starting position as a type bar returns from the printing position into its position of rest on type bar cushion bar l5. Loose dog 31 will engage the next tooth 24 on wheel 22 completing a single spacing operation of the escapement in the return movement to starting position.

Where a key lever 4 is operated to secure the printing of a character, without operating supplemental universal bar 8!, the type bar will operate the escapement mechanism only through universal bar 69 in the usual manner, which will obtain a full spacing operation provided by movement of loose dog 3! between fixed stops 35 and 43 in cooperation with fixed dog 58. This produces a double letter spacing movement of the carriage, as distinguished from the single letter spacing movement obtained in the operation of pivoted. stop 45 with stop 36 in controlling loose dog 31.

In writing upper case letters the operator depresses one of the case shift levers 97, as shown in Figs. 1 and 5, to shift type segment H into the upper case position and simultaneously move supplemental bar 8! downwardly into the upper case position. Lower case selector bar 83 will be positioned below the end of foot on selec-v tor levers 93 in upper case position of bar 8|. Foot 95 will be moved in a clockwise direction, as shown in Fig. 1 to engage one of the fingers 84 on upper case selector bar 82 when a key lever is operated to move the type bar to print an upper case letter. This will operate supplemental universal bar 8! in the same manner as described above to produce a single letter spacing operation of escapement rocker 35 with the movement of the supplemental escapement mechanism being slightly in advance of the usual escapement operation controlled by type bar actuation of universal bar 30.

Sleeve 68 on pivoted actuating arm 61 provides for the movement of escapement rocker 35 in the operation of the supplemental universal bar while the adjustment of adjusting nuts 18 provides for the usual escapement operation by universal bar 60.

Where it is desired to produce a double letter spacing movement of the carriage in the upper case position, as distinguished from a single letter spacing movement employed in the lower case position for the same type action, finger 84' is bent into an upwardly and forwardly inclined position where it will not be engaged by the foot 95 on selector lever 93 in the operation thereof by a key lever. In this way, lever 93 may be operated in the upper case position, its operation being idle motion in view of lower selector bar 83 being positioned below foot 95 and the upwardly bent finger 84' extending above foot 95 so that it has free movement without engaging the supplemental universal bar.

A space bar actuating mechanism is also provided on the present typewriter for operating the escapement to secure the usual spacing operation when it is not desired to operate a type action for a letter printing and spacing movement of the carriage. The usual space bar I? is mounted on a pair of space bar levers I08 as shown in Fig. 1. Space bar supporting shaft IE9 fulcrumed at opposite ends in the side frame members of the typewriter has levers [08 attached thereto. A space bar actuating arm HQ has one end mounted on space bar supporting shaft I69 while the opposite end extends to a position forwardly but adjacent back plate I.

A tension spring I l I has one end secured to back plate I and the opposite end to laterally extending arm I i2 on the rear end of space bar actuating arm ill] for normally moving space bar I0 1 upwardly and resiliently retaining it in an upper position at the front of the typewriter keyboard. This moves the rear end of space bar actuating arm Ill] downwardly at the rear of the machine into its normal position of rest.

A space bar push link H3 has the lower end pivotally mounted on the rear endof space bar actuating arm H0 with the upper end slidably engaged in an aperture in lower comb l8 and a roller l I mounted on the upper extremity thereof in a position immediately below pivoted stop 45 for engagement with laterally extending operating projection 52. Whenever space bar I01 is depressed it will move space bar push link I I3 upwardly and operate pivoted stop 45 into the operative position to secure a single space movement of the escapement mechanism and the carriage through limited movement of loose do 31. This single space movement of the carriage will occur in each successive operation of space bar I01.

It will be understood that wherever it should be desired to obtain a double spacing operation of the carriage by the space bar instead of the single spacing operation described herein, that this may be obtained through the usual space bar construction and linkage mechanism used for directly operating escapement rocker 35 in a well-known manner. However, as herein disclosed it is desirable in writing some languages where a variable space mechanism is used in the typewriter to have a space bar operation that will secure a single spacing movement of the carriage instead of a greater spacing movement thereof such as the double spacing obtained through the operation of universal bar 60. v

It will be seen from the above description and 12 drawings that by providing pivoted stop 45 with the bracket for mounting it on escapement rocker 35 and the supplemental universal bar mechanism for operating slide 15 as attachments to a standard typewriter construction. in which the escapement wheel has been exchanged for one with additional teeth, a rather simple and inexpensive construction has been provided for obtaining a duplex escapement movement of the typewriter escapement mechanism and carriage.

The invention claimed is:

1. In a typewriter having a plurality of type actions, each including a key lever and a case shiftable type bar, a carriage movably mounted on a frame and normally operated in one direction, an escapement mechanism including an escapement wheel, a rocker having movable and fixed dogs cooperating with said escapement wheel in the movement of the rocker for producin letter spacing movements of the carriage, a pair of fixed stops mounted in spaced relation on said rocker at opposite ends of said movable dog for limiting movement thereof in relation to the fixed dog for cooperation in securing a fixed letter spacing movement of the carriage, and a universal bar actuated in the operation of each type action to oscillate said rocker to produce a letter spacing operation of the carriage, a movable stop pivotally mounted on said rocker and movable into and out of an operative position between said fixed stops for engagement with one end of the movable dog to limit the operation thereof in cooperation with the fixed stop on the opposite side of said movable dog to produce a smaller letter spacing operation of the carriage than the spacing obtained in the cooperation of the fixed stops, a supplemental universal bar movably mounted on said typewriter and connected to said movable stop for movin it into operative movable dog engaging position in the movement of said supplemental universal bar, a plurality of selector levers each mounted for engagement of one end with and operation by a selected key lever while the opposite end is positioned to engage and move said supplemental universal bar in operation by said key lever, and means on said supplemental universal bar movable selectively between operative and inoperative positions, engageable by said opposite ends of said selector levers in operative position and selectively controlling a supplemental universal bar operation by said selector levers in the operation of selected key levers for selectively operating said movable stop to produce smaller letter spacing movements of the carriage in the operation of said typewriter.

2. The combination claimed in claim 1, comprising a bracket detachably mounted on said rocker formed with one of said fixed stops and havin a laterally extending arm pivotally mounting said movable stop and resilient means for normally operating said movable stop on said bracket for retaining it in an inoperative position.

3. The combination claimed in claim 1, said supplemental universal bar having a pair of projecting portions and being shiftably positioned with the type bars for complementary cooperation with the selector levers operated by said key levers for individual cooperation with said selector levers in upper and lower case shift positions of the type bars.

4. The combination claimed in claim 1, said supplemental universal bar being shiftable with the type bars and formed with a pair of spaced parallel flanges formed for individual engagement with the selector levers operated by said key levers in upper and lower case positions, respectively, of the type bars of said typewriter, one of said flanges being formed to provide a plurality of tongues, one for cooperation with each selector lever, said tongues being bendable into and out of operative position for selectively controllin operation of the supplemental universal bar by each selector lever.

5. The combination claimed in claim 1, comprising a space bar actuating means on said typewriter and complementary interengaging parts on said pivoted stop and space bar actuating means for engagement in the operation of the space bar for moving said pivoted stop into operative position and simultaneously operating said rocker to produce a carriage spacing movement limited by said pivoted stop.

FREDERICK W. SCI-IREMP.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,250,416 Barr et a1 Dec. 18, 1917 1,676, 78 Myers July 10, 1928 10 2,212,435 Buschmann Aug. 20, 1940 2,527,213 Graepel Oct. 24, 1950 FOREIGN PATENTS Number Country Date 292,338 Germany of 1916 528,976 Great Britain of 1940