US1920777A - Typewriter - Google Patents

Description

J. H. BARR TYPEWRITER Aug. 1, 1933.

Filed May 19, 1930 2 Sheets-Sheet J. H. BARR TYPEWRITER Aug. 1 1933.

Filed May 19, 1930 2 Sheets-Sheet 2 Patented Aug. 1, 1933 UNITED STATES TYPEWRITER John H. Barr, Ithaca, N. Y., assignor to Bar!- Morse Corporation, Ithaca, N. Y.

Application May 19, 1930. Serial No. 453,444

12 Claims.

This invention relates to typewriters, and particularly to the mechanism for feeding the ribbon step by step. More particularly, the invention relates to an improvement in the ribbon feeding mechanism set forth in my prior Patent No. 1,717,362 issued June 18, 1929. Heretofore it has been a common practice to feed the ribbon step by step by power taken from the finger operated printing mechanism but this requires extra pressure on the part of the fingers in operating the keys of the printing mechanism, and therefore, operation of such printing mechanism is tiring to the typist.

In another system of ribbon feed, the sources of power for feeding the ribbon is the carriage spring, which effects the step-by-step carriage feed. With this system it has been usual to gear the ribbon spool shafts to the carriage spring drum, with an interposed ratchet in the train of mechanism, so that the carriage feed and ribbon feed are in synchronism during all right-to-left movements of the carriage. With this system the ribbon is fed with each printing stroke, or space bar stroke, also when tabulating or when displacing the carriage by hand from right to left. The power for feeding the ribbon is derived from the carriage spring, and energy so taken is restored to the spring on return of the carriage to the left for beginning the next line. The effort of feeding the ribbon is not appreciable, but the ribbon is not used uniformly owing to travel of the ribbon with hand displacement of the carriage. Furthermore in such rapid right-to-left motion the spools may spin and thereby cause over-traveling, looping, and possible tangling of the ribbon. These objections are overcome in the present invention in which the spring drum and interposed mechanism feed the ribbon only when the carriage undergoes its step-by-step right to left motion under the control of the escapement.

An object of the invention is to improve the ribbon feeding mechanism of typewriters, and relieve the finger tips of the necessity of exerting the extra pressure requiredto feed the ribbon along; with which the key resistance of the printing mechanism is materially reduced; with which the ribbon will be operated step by. step in accordance with the travel of the carriage under the control of the escapement; with which the ribbon will not be operated during the return travel of the carriage; with which the ribbon will be used in actual impressions more evenly from end to end than in prior instances where the ribbon is fed along by the carriage; with which the ribbon may be automatically reversed after it has traveled in eitherdirection a desired extent, and operated in either direction by the travel of the carriage under the control of its escapement; with which spinning or overrunning of the ribbon will be avoided; with which the reversal of the direction of feed of the ribbon will be effectively and dependably accomplished at the desired time and always while the carriage is being operated step by step under the control of its escapement, Whether in printing or spacing operation; and which will be relatively simple, dependable, compact and inexpensive.

Other objects and advantages will be apparent from the following description of an embodiment of the invention, and the novel features will be particularly pointed out hereinafter in connec- 'tion with the appended claims. I

In the accompanying drawings:

Fig. l is a plan of a portion of a typewriter, and illustrating the ribbon feeding and reversing mechanism constructed in accordance with this invention;

Fig. 2 is an elevation of part of the means for feeding the ribbon step by step in accordance with the travel of the carriage;

Fig. 3 is a schematic elevation illustrating the mechanism for causing a reversal of the direction of travel of the ribbon by an operation of the space bar of the printing mechanism; and

Fig. 4 is a view similar to Fig. 3, but illustrating the position of the parts while causing a reversal in the direction of travel of the ribbon.

In the illustrated embodiment of the invention, the ribbon 1 (Fig. l) is connected at its ends to and wound upon spools 2. Each spool 2 is mounted upon a spindle 3 which is suitably mounted in a frame 4, Fig. 3. The frame may also include the usual guard 5 for the spool as usual in typewriters. The lower end of the spindle 3 mounts a driving gear wheel 6 which may be inthe nature of a stamped worm gear wheel. A shaft 7,. is

'rotatably mounted in a suitable reversing frame 8, and extends along corresponding sides of th spindle shafts 3 as shown in Fig. 1.

The cross shaft 7 is provided, adjacent each gear wheel 6, with a driving worm gear or screw 9 which is shiftable into and out of driving engagement with the adjacent gear wheel 6 upon oscillation of the reversing frame 8. The reversing frame 8 is pivoted intermediate its ends upon a suitable part of the machine frame 10, through the medium of a pivot screw 11, and when one worm gear 9 is shifted into engagement with one gear wheel 6 by the rocking of the reversing franie 110 8 upon the pivot screw 11, the other worm gear 9 will be shifted out of engagement with its re:- lated gear wheel 6.

The gears or screws 9 are oppositely pitched, so that when the shaft 7 is rotated in one direction, the two worm screws 9 will be rendered effective alternately and thus will cause a reverse in the direction of travel of the ribbon 1 between the spools. The shaft '7, at a point closely adjacent the pivot 11 of the reversing frame 8, is provided with a gear 12, Figs. 1 and 2, which is fixed thereon, and this gear meshes with a gear 13 on a drive shaft 14. The shaft 14, Fig. 2, is disposed crosswise of the shaft '7, and the gear 13 may be removably fixed on the shaft 14 by means of a set screw 15 carried by a boss on the gear which fits over the shaft 14.

The shaft 14 is rotatably mounted in bearing lugs 16 and 17 of a suitable frame member 18 which-is attached to the main frame of the typewriter in any desired manner. The end of the shaft 14 which passes through the bearing lug 17 and carries the gear 13 is reduced slightly in diameter so as to provide a shoulder which abuts against one face of the lug 17 to limit endwise movement of the shaft 14 in one direction, movement of the shaft 14in the other direction being normally opposed by a collar 19 which is secured to the reduced end of the shaft 14, and abutting the other face of the lug 17, by a set screw 20.

The other end of the shaft 14 is provided with a gear 21 which meshes with and is driven from the gear 22, which in turn is connected to and rotates with the escapement wheel 23. The escapement wheel 23 is connected to a pinion 24 through the medium of a clutch element 25, the clutch element 25 and the pinion 24 having cooperating abutting ratchet faces which provide a driving connection in one direction of rotation of the pinion 24 and permit free rotation of the pinion 24 in the opposite direction. The clutch element 25 is resiliently pressed into engagement with the pinion 24 in any desired manner, such as by a suitable spring 26, so that the clutch element 25 may move endwise of its axis of rotation in order that it may ratchet over the pinion 24 when the pinion 24 is rotated in the direction given it during return travel of the carriage.

The clutch element 25 may also have an annular groove 27 for engagement by an operating or carriage release member, not shown, as usual in typewriters, whereby the clutch element may be shifted positively out of engagement with the pinion 24 by the usual or any suitable carriage release mechanism, now shown. The pinion 24 meshes with a rack bar 28 which is connected to and travels with the carriage 29, Fig. 2. The rotation of the escapement wheel 23 is controlled by the usual or any suitable mechanism, not shown, whereby the travel of the carriage is regulated step by step under the control of the printing mechanism or the space bar mechanism.

A spindle 30, Figs. 1 and 3, is disposed parallel to each shaft or spindle 3 at one side thereof. Each spindle 30, at its upper end, is provided with an arm 31 which extends into a position along side of the peripheral groove of the spool 2 and is provided with a slot or aperture 32 through which the ribbon 1 passes as it leaves or is wound upon that spool. The slot 32 serves as an aper ture for guiding the ribbon. An arm 33 is fixed upon the lower end of the spindle 30 so as to oscillate'therewith, the arm 33, spindle 30 and arm 31 together forming an offset lever whose axis of oscillation is the axis of the spindle 30.

The arm 33 is provided with a pair of studs 34 and 35 which are carried by and depend from the un-' der face of the arm 33, and which are spaced apart in a direction radially of I the spindle 30.

A reversing element or arm 36 is disposed against the underface of the arm'33, so as to extend toward the spindle 30 and form an endwise extension of the arm 33, that may be referred to as an interponent. The stud 34 extends through a slot or aperture 37 provided in the arm or element 36, the slot 37 being elongated in a direction somewhat radially of the spindle 30, that is, lengthwise of the arm 33, so that the arm or element 36 may be shifted endwise of the arm 33 to a limited extent. The stud 35 extends through a somewhat similar slot 38 in the arm or element 33.

The slot 38 has approximately the same length as the slot 37 so as to permit of the movement of the arm 36 toward and from the spindle 30, but is also considerably wider than the portion of the stud which passes therethrough, so that the arm or element 36 may move laterally of the arm 33 to a limited extent, the arm 36 rocking about the stud 34 as a fulcrum during such lateral swinging movement of the element 36.

A spring 39 is connected between the frame 10 and the end of the element or arm 36 nearest the spindle 30. The spring 39 exerts a turning torque upon the element 36, with the stud 34 as a fulcrum, so as to maintain the stud 35 against one side of the slot 38, as shown at the right hand end in Fig. 1. The spring also, when the stud 35 abuts against the adjacent side of the slot 38, tends to move the arms 36 and 33 together about the axis of the spindle 30, and in a direction to carry the guide arm 31 toward the adjacent spool, until 'the arm 33 engages a stop 33a.

The arm or element 36 is provided with a stud 40 which engages with the reversing frame 8, when the arm 36 is shifted endwise along the arm 33 toward the spindle 30. and shifts it in a direction to carry the adjacent end of the shaft '7 and its adjacent worm screw 9 into driving engagement with the gear wheel 6 which drives the adjacent spool to wind the ribbon thereon. A similar construction identified by corresponding numerals is provided adjacent the other spool and operates in a similar manner to shift the reversing frame 8 in the opposite direction so as to carry the other worm screw 9 into driving engagement with its related or adjacent worm wheel 6. During the rocking of the frame 8, the gear 12 will remain in driving engagement with the gear 13 of the shaft 14, because the gear 12 is arranged in close proximity to the pivot or fulcrum 11 about which the frame oscillates, and at that point the movement of the gear 12 with the shaft 7 will be very small and not suflicient to disengage it from the gear 13.

The ribbon, at a point spaced from but adjacent each end, is provided with an eyelet or button 41, Fig. l, which is too large to pass through the slot 32 in the guide arm 31. When the ribbon 1 has been nearly unwound from one of the spools 2, such as that at the left in Fig. l, the button 41 will engage against the arm 31, and continued travel of the ribbon in the same direction will then cause rocking of the engaged arm 31 about its spindle 30, that is, in a clockwise direction at the left hand end of Fig. 1. The normal position of the arms 31, 33 and 36 is shown by dash lines at the left hand end in Fig. 1, and the position of the same parts after movement by the button 41 is the printing mechanism.

shown by the full lines at the same end or side of Fig. 1.

When the arm 31 is rocked in this manner by the button 41 of the ribbon, the arm or element 36 is set for movement in'an endwise direction to cause a shifting of the shaft 7 into driving engagement with the adjacent gear wheel 6, through the medium of the printing mechanism and the space bar mechanism which will now be described.

The printing mechanism comprises a plurality of type bar actuated drivers 42, Figs. 3 and 4, only one of such drivers being shown. Such printing mechanism is illustrated in'my U. S. Patent No. 1,674,273, issued June 19, 1928, to which reference may be had for a full disclosure. The drivers 42 are actuated in a more or less endwise direction by levers 43, which are in turn actuated by type keys 44. The drivers 42 are arranged in a row acrom the typewriter and a universal bar 45 is disposed along the ends of the drivers 42, so that when any driver is moved approximately endwise by the depression of its key, the universal bar 45 will be rocked rearwardly from the position shown in Fig. 3 into the position shown in Fig. 4, and toward the elements 36.

The universal bar 45 is provided with push members 46 on the face towards the elements 36, which push members normally clear the adjacent ends of the elements or arms 36 when the latter are in their normal positions, such as that shown at the right hand end in Fig. 1, or in dash lines at the left hand end in Fig. 1. When the ribbon guide arms 31 are in normal positions, the actuation of the universal bar 45 by the printing mechanism will have no effect upon the elements 36.

When one of the elements or arms-36 has been rocked by the engagement of a button 41 of the ribbon with the related guide arm 31, as shown in full lines at the left side in Fig. 1, the free end of that arm or element 36 will lie in the path of movement of the member 46 at the corresponding end of the universal bar, Thereupon the actuation of any key of the printing mechanism will rock the universal bar 45, and the member 46 thereof will engage the interponent arm or element 36 and push it endwise toward the spindle 30 during which movement the stud 40 will engage the reversing frame 8 and shift it with the shaft 7 and carry the adjacent worm screw 9 into driving engagement with the adjacent gear wheel 6, at the same time disengaging the worm screw 9 at the other end of the shaft 7 from its related gear wheel 6.

If a button 41 should attemptto move its arm 31 and shift the interponent element 36 related thereto into the path of the member 46 of the universal bar while that member 46 is not retracted, the interponent arm or element 36 may rock about the stud 34 as a fulcrum, dm'ing which the other stud 35 will move across its related slot, the springs 39 being tensioned during this movement so as to exert a yielding pressure urging the interponent arm 36 to follow the arm 33. This presses the arm 36 against the side of member 46 resiliently, and immediately upon the retraction of the member 46 which would be before the next actuation of a printing key, the interponent 36 will be snapped laterally across the path of the member 46 into a position to be operated thereby at the following actuation of any type key 44 of Following the rocking of the shaft 7 in this manner, the ribbon will be wound in the opposite direction between the spools 2, at the beginning of which movement the button 41 which has caused the reversal, will move away from its arm 31, wh reupon the spring 39 will return the arms 31, 33 and 36 to their normal positions in which they are not actuated by the universal bar.

Inasmuch as the carriage, in moving step by step under the control of the escapement, will operate the ribbon in a similar manner, such step by step movement will be caused when the space bar key 47, Figs. 3 and 4, is operated to produce a letter spacing movement of the carriage, as well as when the carriage is spaced by the type keys. If considerable travel should be given the carriage by repeated operations of the space bar 47, the button 41 might operate its guide and interponent 36 into position to cause a reversal of the ribbon feed, but no reversal would occur until the next actuation of the printing mechanism.

Since the button 41 cannot pass through the slot 32, some provision shouldbe made to actuate the reversing mechanism when the space bar also is operated. For that reason, the space bar or key 47, Figs. 3 and 4, which is pivoted at 48 may have depending arms 49 each with a slot 50 at its lower end. A stud or pin 51 carried by each pivoted arm 52 of the spacing mechanism operates in the slot 50, so that upon depression of the space bar or key 47, the levers 52 will be rocked about their fulcrum. A pusher link 54 is pivotally connected by a pin 55 to the lower end of each lever 52, and extends rearwardly beyond the universal bar 45 as shown in Figs. 1 and 3.

The rear end of each pusher link 54 has a rearwardly extending slot 54a, which slides on a headed stud 56 carried by the adjacent end of the reversing frame 8, the stud 56 serving to slidingly support the rear end of the pusher link 54. The pusher links 54 are provided at opposite ends or sides of the machine, as shown in Fig. 1, it being noted that the levers 52 (Fig. 1) are fixed upon a common cross shaft 57, which serves as their fulcrum, so that both pusher links 54 will be operated in unison. Both links 54 are similarly mounted at their rear ends on the studs 56 of the reversing frame 8.

Each pusher link 54 has a nose or terminal 58 which normally clears the stud 40 of the adjacent interponent 36 when the interponent is in its normal ineffective position, as shown in full lines at the right in Fig. 1, so that when the ribbon guide arms 31 are in normal positions, pusher links 54 in moving rearwardly will clear the studs 40 and have no effect upon the interponent elements 36. When either interponent 36 is shifted laterally across the path of either member 46, as shown by full lines at the left side in Fig. 1, the stud 40 of the shifted interponent 46 will then lie in the path of travel of the projection 58 of the adjacent pusher link 54 and thereupon an operation of the space bar key 47 will force the pusher links 54 rearwardly and one of them will engage and push a stud 40 in a direction to cause a reversal of the direction of feed of the ribbon 1. The free end of each nose 58 is of such size that the stud 40 can never get in front of it.

From the foregoing, it will be observed that when a button 41 on the ribbon moves one of the guide arms 31 in a direction to place an interponent 36 in the path of the member 46 of the universal bar, any subsequent operation of either the space bar or the printing mechanism will cause a rocking of the shaft 7 and a reversal in the direction of feed of the ribbon automatically. The shaft 7 may be confined yieldingly in its two extreme positions in any suitable manner, such as by holding device 59', shown conventionally in Fig. 1. Such a holding device which may be employed is illustrated and described in my U.S.

Patent NO. 1,717,362 issued June 18, 1929.

The operation of the ribbon feed mechanism should be obvious from the foregoing description, but will be briefly stated. Any travel of the carriage in a return direction will have no effect upon the ribbon feed mechanism because during such movement, the ratchet clutch element 25 will permit the escapement 23 to remain stationary. The clutch element 25 will also permit the escapement 23 to remain stationary during the travel of the carriage in either direction when the carriage is released, by the usual carriage release, mechanism or during tabulating operation. Since the ribbon feeding mechanism only operates when the escapement is operated, the ribbon feeding mechanism will remain stationary, except when the carriageis given a step by step travel under the control of the escapement.

Assuming that the shaft '7 is in the relative position shown in Fig. 1, the ribbon is moved step by step towards the right, Fig. 1, in accordance .with the travel of the carriage in letter spacing direction under the control of the escapement wheel 23, and when the ribbon has been largely unwound from the left hand spool in Fig. 1, a

button 41 will cause a shifting of the interponent 36 (at the left in Fig. 1) from the dash line position to full line position.

Since the step by step travel of the carriage is produced by operation of the printing mechanism or operation of the space bar, the next succeeding operation of either the space bar or the printing mechanism will cause an endwise movement of the shifted interponent arm 36, and a rocking of the shaft '7 clockwise in Fig. 1, so as to carry the worm screw 9 at the left hand end into engagement with its related gear 6, and disengage the other worm screw 9 from its related gear wheel 6.

The continued travel of the carriage will then drive the ribbon in the other direction and after the ribbon has been largely unwound from the other spool, a similar operation will occur adjacent the other spool, whereupon the shaft 7 will be returned to the position shown in Fig. 1.

With such an arrangement, it will be noted that the force required to feed the ribbon is obtained from the carriage spring, which lessens the force normally necessary to operate the printing mechanism or space bar, and therefore operation of the printing mechanism is less tiring to an operator. It will also be noted that when the carriage is displaced by hand or by the tabulator, the ribbon feeding means will not be operated, and consequently spinning of the ribbon by rapid operations of the carriage or overrunning of the ribbon upon sudden stopping of the carriage is avoided. This results in more uniform service of the ribbon, decreases the frequency of the ribbon reverse, and the ribbon is used in actual impressions more evenly from end to end.

It will be obvious that various changes in the details, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. In ribbon feeding mechanism, a pair of gear wheels arranged in spaced relation to one another and each having means for mounting a ribbon spool for rotation therewith, a shaft extending from adjacent one wheel into proximity to the other, a driving gear carried by each end of the shaft and engageable with the gear wheels, means mounting 'said shaft for a limited movement to engagesaid gears with said gear wheels, alternately, one gear being disengaged from its wheel when the other is engaged with its wheel, an interponent adjacent each end of the shaft, means mounting each interponent for movement in different paths crosswise of one another, each interponent and said shaft mounting means having cooperating parts by which movement of each interponent in one direction inpne path will shift the adjacent end of the shaft in a direction to mesh its adjacent gear with the adjacent gear wheel, means including a member carried by the ribbon adjacent each end for shifting each interponent in another of said paths in which it is not effective to shift said shaft,

a plurality of printing devices, a space bar, and

means operable by said space bar or any of said printing devices for actuating any interponent which may have been moved by said ribbon to cause a movement of the shaft in a direction to reverse the direction of travel of the ribbon.

2. A typewriter of the type having carriage and a ribbonattached to and connecting'two spaced spools upon which the ribbon is wound alternately with a button on the ribbon near each end thereof, comprising a driving gear wheel for each spool, a shaft having two driving gears, each engageable with one of said gear wheels, means mounting said shaft for movement to mesh said gears alternately with the gear wheels, a driving connection between said shaft and the carriage, whereby step-by-step travel of the carriage operates said shaft, type key actions, a space bar, and means operable by said space bar and said key actions and rendered effective by the buttons on said ribbon for shifting said shaft to disengage one gear from its gear wheel and engage the other gear with its gear wheel upon operation of either a type key action or said space bar, after the ribbon has travelled a desired distance in either direction.

3. In. a typewriter, a carriage, escapement mechanism for regulating the travel of said carriage, one-way clutch mechanism connecting said carriage andsaid escapement, whereby the escapement controls the carriage only in travel in one direction, reversible ribbon feeding mechanism, means connected to said escapement mechanism'for operating said feeding mechanism, concurrently therewith, whereby said rib bon feeding mechanism will operate step by step during the travel of said carriage under the control of said escapement and be motionless during the return travel of the carriage, type key actions, a space bar mechanism and means controlled by said ribbon, and operated directly by said space bar mechanism and key actions at a single stroke of either for causing a reversal of said ribbon feeding mechanism after the ribbon has traveled in either direction a desired extent.

4. In a typewriter, a pair of ribbon spools and a ribbon connecting the same, means mounting each spool for rotation, a carriage, means for driving each spool and shiftable to cause operation of the spools alternately, means for operating said spool driving means step by step in accordance with the travel of said carriage, printing mechanism step by step, carriage letter spacing means, and means positively controlled by said ribbon and directly operated by either said carriage spacing means or said printing mechanism for causing a shifting of said spool driving means in a manner to cause areversal by a single stroke of either said spacing means or said printing mechanism, of the direction of travel of the ribbon after the ribbon has traveled in either direction a desired extent.

5. In a typewriter, a pair of spools, a ribbon connected at its ends to said spools and extending between them, whereby the ribbon may be wound alternately on said spools, a carriage, means operable from said carriage for operating said spools to wind the ribbon in accordance with the travel of the carriage, and adjustable to vary the direction of winding of said ribbon on said spools, a plurality of printing devices, a universal bar operable by any of said printing devices, carriage letter spacing mechanism, members directly operable upon said spool operating means to cause a reversal in the direction of travel of said ribbon at a single operation of either member, and shiftable positively by said ribbon into and out of positions in which they are directly operated by said universal bar and said carriage spacing mechanism, to cause reversal in the direction of travel of said ribbon.

6. In a typewriter, a pair of spindles mounting ribbon spools, each spindle having a gear wheel, a reversing frame pivoted between its ends and at a point approximately midway between said spindles, a shaft rotatably mounted on-said frame, extending into proximity to said gear wheels, and having a driving gear at each end engageable and disengageable with the adjacent gear wheel when said frame is rocked, each gear being engaged with its gear wheel when the other gear is disengaged from its gear wheel, a lever mounted adjacent each spindleand operable by said ribbon when the ribbon has unwound from the adjacent spool a desired extent, an interponent connected to said lever for sliding movement radially of the lever and also movable on said lever laterally thereof, printing mechanism, a member operable at each operation of the printing mechanism in a path across which said interponent travels when said lever is rocked by said ribbon, the movement of said member after the interponent has been shifted into its path, causing sliding radial movement of said interponent on said lever, said interponent having means engageable with said frame to cause the movement of said shaft in a direction to reverse the direction of travel of said ribbon, and means resiliently holding said interponentat one limit of its lateral movement on said lever, whereby upon movement of said lever in a direction to carry the interponent across the path of said member, said interponent may yield if it moves across said path when said member is not in retracted position, and then snap into position across said path upon retraction of said member.

7. In a typewriter, a pair of gear wheels, a ribbon, a pair of spools driven by said gear wheels and connected to the ends of said ribbon, and upon which said ribbon is wound alternately, a shaft having a driving gear on each end thereof which is engageable with the adjacent gear wheel, means mounting said shaft for movement to shift said driving gears alternately into engagement with said gear wheels, whereby said driving gears element in said lateral direction, printing mechanism, and carriage spacing means, each normally ineffective upon said element but directly operable thereon when said element is shifted in said lateral direction to cause movement of said element in a direction to effect a reversal in the direction of travel of said ribbon.

8. In a typewriter, a ribbon, a pair of spools to which the ends of said ribbon are connected, and upon which the ribbon is wound alternately, a gear wheel connected to each spool for rotating it in a direction to wind the ribbon thereon, means for driving said gear wheels alternately, a member shiftable by said ribbon when the ribbon has unwound from a spool to a desired extent, a bar having pin and slot connections to said member at a plurality of points along said member laterally of its direction of movement in shifting, whereby said bar may be moved laterally of said shifting movement to a limited extent, one of said slots being wider than the pin which runs therein, whereby said bar may also rock upon said member about the other pin as a fulcrum to an extent permitted by the width of the slot, a spring connected to said bar and urging said bar yieldingly in one direction about the fulcrum pin, so as to maintain the other pin yieldingly against one wall of said wide slot, and also urging said member in a direction opposite to that given it by said ribbon when the ribbon has unwound to the desired extent, means operable by said bar to cause a reversal in the direction of travel of said ribbon produced by said driving means when the bar is shifted endwise of said member, key actuated mechanism, an element operated by said key actuated mechanism normally clearing said bar but operable thereon to shift it endwise of said member when the bar has been shifted with said member by the ribbon, whereby if said bar is shifted laterally with said member when said element is not retracted, said bar will be pressed against the side of said element by continued movement of said member and then snapped into the path of said element after the latter has been retracted.

9. In a typewriter, a pair of ribbon spools on which a ribbon is mounted and wound and unwound, a gearwheel connected to and driving each of said spools, a shaft, gears mounted on said shaft, means mounting said shaft for movement to engage and disengage said gears alternately with said gear wheels and control the direction of operation of said ribbon by said shaft, an operating element operable on said shaft to cause a reversal in the direction of travel of the ribbon and also movable laterally of said direction without causing movement of said shaft, a space bar, a shift element operable thereby and normally clearing said operating element when said space bar is operated, printing mechanism, a member operable back and forth at each operation of said printing mechanism and also normally clearing said operating element, and means controlled by said ribbon and causing lateral movement of said actuating element into a position to be actuated by said shift element and said member which is operated by the printing mechanism, said operating element when operated by said shift element or said member which is operated by said printing mechanism being moved in a direction to cause a reversal in thedirection of travel of said ribbon.

10. In a typewriter, a ribbon, a carriage, means for feeding said ribbon selectively in either of two directions in accordance with the letter spacing travel of said carriage, and including a member i'or controlling the direction of travel of the ribbon, printing means having an element operable thereby in a prescribed path, and letter spacing means also having an element operable thereby in a prescribed path, and means controlled by said ribbon and operable after the ribbon has traveled a desired distance in either direction for shitting said controlling member into the paths of travel oi said elements, whereby the next following operations of either printing means or said spacing means will cause a reversal of the direction of travel of said ribbon.

11. In a typewriter, a ribbon, means for feeding the ribbon in either direction, key actuated means having a member movable intermittently in a prescribed path, a control element formed of two connected sections, one of said sections being operable by said ribbon, after the ribbon has been fed in one direction a desired extent, in a direction to place the other of said sections in said path for actuation thereby, said one section completely supporting said other and permitting free movement of said other section thereon in two crosswise directions, oneof which is the direction of travel when operated by said ribbon, said other section being operable on said feeding means to reverse it when moved in the otherof said crosswise directions, means yieldingly holding said other section in a desired relation to said one section during their movement by the ribbon, whereby actuation of said member while said other section is in its path will cause movement of said other section on said one section in the other of. said crosswise directions, and reversal of said feeding means.

12. In a typewriter, a ribbon, means for feeding the ribbon in either direction, a lever rocked by said ribbon after the ribbon has been fed in one direction to the desired extent, a bar having two separate pin and slot connections to said lever, said connections being spaced apart radially of the lever whereby the bar may move radially of the lever to a limited extent, one of said slots being wider than the related pin whereby said bar may also rock on said lever about the pin in the other slot as a fulcrum to a limited extent, means for holding said bar yieldingly against one side of the slot, and key actuated means for engaging and operating said bar radially of the lever after the lever and bar have been moved by said ribbon, whereby said bar may yield on said lever when moved by said ribbon until said key actuated means is retracted, said bar, when moved radially of the lever, operating said feeding means to reverse the direction of travel of the ribbon.

JOHN H. BARR.

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