US2304216A - Typewriting and like machines - Google Patents

Description

Dec. 8, 1942. R. G. 'rHoMPsQN TYPENRITING AND LIKE MACHINES Filed Sept. 29. 1939 '3 Sheets-Sheet l NMI l. IWQN As Y u l l m l EQU 5. m uw hh m c f w Q mmm H wm g Nm n Q m5 JAS n QN 8, 1942. R. G. THOMPSON TYPEWRITING AND LIKE MACHINES 3 Sheets-Sheet 2 Filed Sept. 29, 1939 www De 8, 1942. R. G. THOMPSON TYPEWRITING AND LIKE MACHINES 3 Sheeis-Sheet 5 Filed Sept. 29, 1939 3 wc/whom /Pwsfu 77/0MP30N UNITED ls'rlrras PATENT] orales I v'r:revvnrig'nvoz:1.132.121lus:Marialuisa wel G. Thompson, West Bartford,-conn., aa-

signor to Remington Band lne., Buffalo, N. Y., a corporation of Delaware application semester ze, ma, serial Nq. 291,135 s claims. l(ci. iai-m) My invention relates to typewriting and like machines, and more particularly to improved ribbon feeding mechanism therefor.

The main .object of my invention, generally stated, is to provide improved means of the character specified which is simple, reliable and highly effective in operation.

A further object of my invention is to provide a ribbon feeding mechanism wherein the direction of feed of the ribbon is automatically reversed, and wherein provision is made against locking such ribbon reversing mechanism against operation when the machine is operated with the ribbon spools removed as in cutting or typing stencil sheets.

A still further object of my invention is to provide such ribbon feeding mechanism wherein certain parts thereof are carried by an exterior frame or casing and other parts are carried by an interior chassis which may be readily removed from said casing.

To the above and other ends which will hereinafter appear, my invention consists of the features of construction, arrangement of parts and combinations of devices set forth in the following description and particularly pointed out in the appended claims.

In the accompanying drawings, wherein like reference characters indicate corresponding parts in the different views:

Fig. 1 is a vertical, transverse sectional view taken through the central portion ofva typewriting machine, and illustrating a suiiicient number of parts thereof to show diy-invention in its embodiment therein.

Fig. 2 is a fragmentary, fore and aft, vertical sectional view taken on line 2-2 of Fig. 1 and viewed in the direction of the arrows at said line.

Fig. 3 is a fragmentary, detail sectional view taken online 3 3 of Fig. 2 and viewed in the direction of the arrows at said line.

Fig. 4 is another fragmentary, detail sectional view taken on line l-I of Fig. 2 and viewed in the direction of the arrows at said line.

Fig. 5 is an enlarged, fragmentary, vertical sectional view of one of the spool shafts and some of the associated parts, the .view showing the parts as they appear when the companion ribbon spool is removed. t

Fig. 6 is an enlarged, fragmentary, horizontal" sectional view taken on line l-C of Fig. 5 and viewed in the direction of the arrows at said line.

. Fig. 7 is an view similar to the upper portion of Fig. 5 but showing certain parts as they appear when the ribbon spool is applied.

I have shown my invention embodied in the present instance in a Remington Model No. 17 typewriting machine in. which the features of the invention may be readily incorporated with but few changes in the existing structure. However, it is to be understood that my invention is not restricted to embodiment in such machine but may be employed in various other types of typewriting and like machines wherever found available.

The drawings show only so much of the construction of the Remington Model No. 17 machine as is necessary to arrive at an understanding of the present invention in its embodiment 4 therein. In this machine, many of the parts including the type actions, key levers and various other related mechanism' are mounted on a removable chassis formed by side plates I0 which are rigidly connected by cross members which are not shown in the drawings. This chassis is removably mounted within an exterior frame or casing which includes a U-shaped member having side portions l2 which extend along the side plates il of the chassisin spaced relation thereto as may be seen in Fig. 1 wherein the left hand side member l2 only of the exterior frame is shown. The removable chassis and associated parts are fully disclosed .in my companion applicationfiled July 26, `1940, Serial No. 347,677.

The two side portions Ilof the exterior frame are rigidly inter-connected by suitable cross members such as the rear cross member I3 shown in part in Figs. l and 2. The lower edge of each of the chassis side plates il rests on companion shelf portions I2* which extend inwardly from the associated side member I2 of the exterior frame. A guide plate Il is secured at I5 to the upper surface of each of the shelf portions I2* to engage the outside surface of the companion chassis side plates Il and thereby prevent lateral shifting of the chassis within the exterior frame. Suitable means, not shown, are also provided for holding the chassis frame against vertical displacement within the exterior frame, which means coact between the chassis side plates l0 and the side portion I2 of the exterior frame and l are readily releasable to permit the chassis and parts carried thereby to be lifted upwardly and forwardly out of the Yexterior frame.

The carriage in the present machine is removably mounted on the rear upper portion of the enlarged, fragmentary, sectional side members Il of the exterior frame. Thus,

a stationary carriage guide member I8 shown in part in Fig. 2 is removably mounted on the side-members I2 of the exterior frame by means which have not been shown, and the traveling carriage frame shown in part at 20 in Fig. 2 is mounted by crossed anti-friction rollers such as 2l, on the supporting member I8 for movement transversely of the machine in the usual manner.

'I'he carriage thus mounted for movement transversely of the machine is impelled in a letter spacing direction from right to left by a spring drum 24 which is mounted to turn about the axis of a screw 25 secured by a nut 26 to the rear cross member I3 of the exterior frame. The spring drum 24 includes the usual spiral internal spring (not shown) which exerts a force tending to turn the drum 24 in a counter-clockwise direction as viewed in Fig. 1, and the spring drum 24 is operatively connected to the carriage by a exible tape 21 which extends around the periphery of the drum. Thus. one end of the tape 21 is anchored to the spring drum while the other end is provided with'a connecting piece 28 which is detachably connected to an arm 28 attached at 30 (see Fig. 2) to the right hand end of the carriage frame member 20. The spring drum 24 thus turns in a counter-clockwise direction to move the carriage in a letter spacing direction from right to left of the machine under control of the usual escapement mechanism (not shown), and a return movement of the carriage accordingly effects a reverse or clockwise direction of turning movement of the drum through the tape 21.

The feeding mechanism for the ink ribbon in the present instance is driven by this turning movement of the spring drum 24, and is so arranged that the ribbon is fed intermittently past the printing point as the spring drum is turned in a counter-clockwise direction to impel the carriage in its step by step movement from left to` right of the machine for the spacing or Written characters. Thus, a ring gear 34 is iixedly secured to the front face of the spring drum 24 in any suitable manner such as by spot welding at 35, which gear 34 normally meshes with a smaller pinion gear 36. The pinion gear 36 is providedl with a hub portion 31 which is mounted to turn freely on the rear end portion of a shaft 38. The shaft 38 extends fore and aft of the machine in the space between the left hand chassis side plate I II and the left hand side portion I2 of the exterior frame as shown in Fig. 1. The rear end portion of the shaft 38 is mounted to turn in a U-shaped member 48 which is pivotally mounted at 4I on a bracket 42 secured at 43 to a horizontal inwardly extending portion 44 on the exterior frame cross member I3. The front end of the shaft 38 is supported by a bearing plate 46 secured at 41 to an upward extension 48 of the guide lug 52 extending forwardly from a bracket 53 which is secured at 54 (see Fig. 1) to the horizontal extension 44 of the cross member I3 of the exterior frame. The U-shaped bearing member 48 is thus normally held under the force of the spring 58 in engagement with a lug 55 (Figs. 1 and 2) on a downwardly extending portion of the bracket 42, and thereby holds the pinion 36 in proper meshed relation with the ring'gear34. The present invention is not particularly concerned with the mounting of the bearing member 40 for pivotal movement. this mounting being provided for at times rendering th ribbon feeding mechanism inoperative through devices which are disclosed in my copending application filed Nov. 17, 1939, Serial No.' 304,988, now Patent No. 2,254,921 issued Sept. 2, 1941.

A one-way driving connection is provided between the hub member 31 of the pinion 36 and the shaft 38 in order that the shaft 38 will be turned only during the letter spacing direction of travel of the carriage. Referring to Figs. 2 and 3, it will'be seen that a disc 68 having a hub portion 6I is secured at 62 on the shaft 38. A pawl 64 is pivotally mounted at 65 on the rear surface of the disc 60, and a wire spring 66 presses the free end of the pawl 64 into cooperative relation with ratchet teeth 61 formed on the front end of the hub portion 31 of the pinion 36. It will be seen in Fig. 3 that the teeth 61 are so shaped that when the hub portionv31 of the pinion gear 36 is turned in a counter-clockwise direction as viewed in Fig. 3, the pawl 64 will be driven by the teeth 61 to accordingly turn the shaft 38 during a movement of the carriage from right to left of the machine for the spacing of printed characters. However, when the carriage is moved from left to right, the hub portion 31 of the gear 36 will be turned in a clockwise direction as viewed in Fig. 3 which causes the teeth 61 to cam the free end of the pawl 84 outwardly therefrom and accordingly this direction of rotation of the gear 36 is not transmitted to the shaft 38. v

In order to insure that the shaft 38 will not be turned in a clockwise direction during the clockwise turning movement of the gear 36, a holding pawl 18 is pivoted at 1I on the bearing member 40, and a wire spring 12 acts on the pawl 10 to normally hold the free end thereof in cooperative relation to ratchet teeth 13 formed on the forward end portion of the hub member 6I of the disc 60. It will be noted that the teeth 13 are oppositely arranged with respect to the teeth 61 on the hub member 31 so that the hub member 6I and accordingly the shaft 38 is securely held by the engagement of the free end of the pawl 18 with one of the teeth 13 when the hub member 6I tends to turn in a clockwise direction. The teeth 13, however, are effective to`cam the free end of the pawl 18 outwardly to an ineffective holding position when the disc 68 is driven in a counter clockwise direction by the gear 36.

Referring to Figs. l, 2 and 6, it will be seen that the front end of the shaft 33 is provided with a beveled pinion gear 15 secured thereto at 16 to mesh with a beveled gear wheel 11 mounted to turn freely on a headed pivot screw 18 threaded into the upper end of the extension 48. The parts of the ribbon driving mechanism thus far described are all mounted on and carried by the exterior frame of the machine while the ribbon itself and the remainder of the ribbon feeding mechanism is mounted on and carried by the removable chassis. Accordingly means are provided in accordance with the present invention for operatively connecting the gear wheel 11 with the ribbon feeding mechanism mounted on the removable chassisvin the chassis to be readily removed.

This connecting means is provided by a pin 88 secured to the gear wheel 11 to extend inwardly therefrom at a point spaced from the pivot screw a manner which permits by bearing openings provided in each of the end plates |0. In this manner, the ribbon driving mechanism carried by the external frame is oper-4 atively connected to the shaft 85 through the pin 80 and bifurcated arm 82 when the chassis is in its normal position, but the bifurcation 8| in they right hand spool shaft I8.

the arm 82 permits the chassis to be lifted upwardly out of the exterior frame and to be-readily replaced therein.

-A beveled gear 88 is secured at 81 to the right hand portion of the drive shaft 85, and at the position of the parts shown in Fig. 1, said gear 88 meshes with a beveled gear 88 secured at 88 to the lower end portion of a tubular ribbon spool shaft 90. Said shaft 90 is supported in a substantially vertical position at the right hand side of the machine in bearing openings in a U-shaped bracket 8| secured at 92 to the right hand chassis side plate I0. A beveled gear 95 similar to the bevel gear 88 is secured at 96 to the left hand portion of the drive shaft 85, and the shaft 85 may be moved to the left in the direction of its length to move the gear 95 into meshed relation with a beveled gear 91 secured at 98 to the lower end of a left hand ribbon spool shaft |00. The left hand ribbon spool shaft |00 which is shown in detail in Fig. 5 is of a tubular construction substantially the same as the right hand ribbon spool shaft 90, the left hand shaft |00 being rotatively supported in a substantially vertical position by a U-shaped bracket |0| which is secured at |02 to the left hand chassis end plate I0.

Means are provided for affording a slight resistance to the turning of the spool shafts 90 and |00, which means includes a collar |05, secured to each of the spool shafts at |06 and a companion expansion spring |01 arranged between each of the collars |05 and the lower arm of the associated bearing bracket. Thus, each of the springs |01 offers a slight frictional resistance to the turning of the companion spool shaft and acts to resiliently hold it '1n its upper position wherein a spacing sleeve |08 on each of the spool shafts engages the companion upper arm of the associated bearing bracket, each of the sleeves |08 being retained against displacement on the companion shaft by a collar |09 secured thereto at H0.

The upper end of each of the ribbon spool shafts 90 and |00 is provided with substantially the same means for holding the inking ribbon spool thereon. Thus, as may be seen in Fig. 5, a hub member I4 is fixedly secured in any suitable manner to the portion of the associated shaft which extends above the bearing bracket, and a supporting flange ||5 is formed on each of the hub members by a circular plate which is securely attached against the lower surface of a shouldered portion of the associated hub member H4. A guide ring ||8 is provided on each of the flanges ||5, which guide ring is disposed concentrically around the hub member ||4 and secured to the ange ||5 by downwardly projecting lugs (not shown) which pass through openings in the companion flange ||5 and are expanded against the walls thereof in the usual manner.

An inking ribbon of the usual construction is shown in Fig. '7 as partly wound around a spool mounted on the left hand shaft |80, which spool comprises flanges |22 secured in the usual manner to an inner core or ring|23 which fits snugly around the guide sleeve ||8 to turn therewith. Referring to Fig. 1, it will be seen that the inking ribbon |20 extends from thisspool at the left hand side of the machine through a ribbon vibrator |25 of the usual construction mounted for vertical movement on a type guide |28, and the otherl end of the inking-ribbon is wound around a spool of like construction Amounted on In Fig. 1 of the drawings, the ribbon feeding mechanism is shown in a condition wherein the right Ahand spool shaft 8l is turned through the engagement of the gears "and, 88 when the carriage is moved from right to left of the machine for the letter spacing of printed characters. Under this condition, the left hand spool shaft |00 is not driven by the shiftable drive shaft 85 due to the separation of the gear 88 from the gear 81 so that the turning of the spool shaft 80 winds the ribbon |28 on` the right hand spool and accordingly unwinds it'from the' left hand spool, thereby causing the left hand spool shaft |00 to turn against the slight friction provided by associated spring |01.

Means are provided in the present machine for automatically reversing the direction of the feed of the ribbon |20 when the supply thereof on one of the spools is exhausted. Under the condition shown in Fig. l, this means operates to shift the feed from the spool shaft 90 to the spool shaft |00 by a longitudinal movement of the drive shaft 85. Thus, referring to Fig. 5. it will be understood that a ribbon reversing member or plunger |30 is provided within each of the hollow spool shafts and |00, each of which plungers is mounted for a slight vertical movement in ya companion bushing |3| secured to the lower-end of the associated spool shaft and having a centrally disposed opening receiving the lower end portion of the companion plunger. The upper end portion of each of the plungers |30 is flattened as shown in Figs. 5 and 7 and an elongated opening |33 in this flattened portion of each plunger receives the hook-shaped end of a companion crank arm |35 pivotally mounted at |30 on an inwardly extending lug of the associated guide sleeve H6. The depending portion of the crank arm |35 is provided with an extending toe portion |35 extending through a verticallydisposed slot |31 in the companion guide sleeve H5. Each of the arms |35 and associated arm |35a constitute a bell crank. The hub portion |23 of each of the ribbon spools |22 is provided with a similar slot or opening which registers with the companion opening |31 when a spool is applied over the associated guide ring H8, as shown in Fig; '1. The toe portion |35a of each of the crank arms |35 engages the inner-most layer of the inking ribbon |20 on the associated spool, thereby holding the crank arm |35 in its position shown in Fig. '1 where the hook-shaped end portion thereof engages the upper wall of the opening |33 in the companion plunger |30 to hold it in its elevated or ineffective position shown in Fig. 5.

When the left hand plunger |30 is thus held in its elevated position by the inner layer of ribbon on the companion spool, the lower end of this plunger is disposed above and out of cooperative relation with a spiral web or cam |40 (Fig. 1) formed on an extending hub portion |4| of the gear 95. Under the condition of the ribbon feeding mechanism shown in Fig. 1, the inking ribbon |20 is being wound on the right hand spool and as the supply of this ribbon on the left hand spool becomes exhausted, or as the last layer thereof is partly unwound to uncover the extending toe portion |35a of the crank arm |85, it will be clear that the plunger |30 will move downward -fby gravity inasmuch as the crank portion |35l will be free to move outward. 'Ihe lower end portion of the plunger |30 at the left hand side of the machine will then be in a position coacting with the spiral web |40 to cause an axial shift of the drive shaft 85 while it is being turned by a letter spacing movement of the carriage. In

other words, the lower end of the left handl plunger 30 in its lowered position is engaged by the side of the spiral web |40 during a turning movement of the drive shaft 85 which causes the spiral web |40 and the shaft 85 to be cammed to theleft as viewed in Fig. l, to a position wherein the gear 95 meshes with the gear 81. This longitudinal movement of the shaft 85 from right to left also causes the gear 86 to become disengaged from the gear 88, and accordingly the direction of feed of the inking ribbon |20 will be reversed so that the ribbon will then be wound on the left hand spool |22 and unwound from the right hand spool. As the first layer of the inking ribbon |20 is wound around the left hand spool, the crank arm |35 will be moved back to its position shown in Fig. 7 thereby raising the left hand plunger |30 back to its normal position wherein the lower end thereof is out of cooperative relation with the spiral web |40.

The plunger |30 which is mounted within the right hand ribbon spool shaft 90 is arranged in a similar manner so that when at least one layer of ribbon still remains on the companion ribbon spool, the extreme lower end of this plunger is disposed above and out of cooperative relation with a spiral web |44 formed on an extending hub portion |45 of the gear 86. However, as the innermost layer of ribbon on the right hand spool is partly unwound, the companion crank arm |35 is allowed to swing outwardly as the toe portion |35a thereof is uncovered. Thus, the plunger |30 within the right hand spool shaft 50 moves downward under the force of gravity so that the lower end thereof cooperates with the spiral web |44 to cause an axial shift of the drive shaft 85. The spiral web |44, however, is oppositely disposed with relation to the left hand spiral web |40, whereby the drive shaft 85 is moved from left to right to re-engage gears 88 and 81 and to disengage gears 85 and 81 when the right hand plunger |30 thus falls to its lower or operative position. Thus, when the supply of ribbon on either one of the two spools becomes exhausted, the drive shaft 85 is automatically shifted in a corresponding direction lto cause the direction of feed of the ribbon to be reversed so that it is wound back on the exhausted spool.

The shiftable drive shaft 85 is resiliently held in either of its two extreme shifted positions by an over-center spring means which has not been shown in detail in the present drawings. Thus, as shown in part in Fig. 1, a pin |48 is carried at the rearward end of a member (not shown) which is pivotally mounted on the chassis of the machine and the pin |46 enters an annular groove |41 provided in the hub of the gear 88, and means are provided, which have not been shown, to coact with the member carrying the pin |46 in the usual manner to resiliently hold the drive shaft 85 either in a position wherein gear 86 meshes with the gear 88 or in its other ther turning movement.

position wherein gear 95 meshes with gear 81. It will be clear that the pin and slot connections |30-8| between the gear wheel 11 and the arm 82 allow the drive shaft 35 to be shifted longitudinally relative to the gear wheel 11 and yet maintain the positive driving connection between the gear 11 and the drive shaft 85 at either shifted position thereof.

In using a typewriting machine for cutting duplicator stencils or other types of work where ink is not transferred to the work sheet, it is often desirable to remove the inking ribbon as well as both of the ribbon spools from the machine. This removal of both of the ribbon spools from a machine employing automatic ribbon reversing mechanism of the present type would ordinarily permit the bell cranks |35 at both sides of the machine to swing outward about their respective pivots |36 and thereby release both of the plunger members |30. If both of the plungers |30 are permitted to drop to their lowered positions coacting with their respective spiral webs |40 and |44, a subsequent turning movement of the drive shaft 85 would cause both of -the spiral webs 40 and |44 to simultaneously coact with their associated plungers |30 and thereby shift the drive shaft 85 slightly in one direction or the other until it becomes jammed or locked against fur- 'Ihis locking of the drive shaft 85 against rotation would accordingly prevent rotation of the spring drum 24 thereby preventing letter space movement of the carriage and rendering the machine inoperative.

In accordance with the present invention, means are provided which coact with at least one of the ribbon spools to prevent the associated plunger |30 from dropping when the spool is removed, thereby preventing the machine from beingi rendered inoperative by the removal of both of the ribbon spools. Said means in the present instance are associated with the left hand ribbon spool mechanism, and referring to Figs. 5, 6, and 7, it will be seen that a second crank arm |50 is pivotally mounted at |5| on a lug |52 depending from the ange ||5 which normally carries the left hand ribbon spool |22. An opening |58 is provided in the guide sleeve ||6 through which a bluntly pointed portion |50"l of the upstanding arm of the crank arm |50 extends. When the left hand ribbon spool |22 is in place, as shown in Fig. 7, the portion |50IL of the crank arm |50 engages the inner wall of the hub |23 of the spool. 'Ihe left hand ribbon spool, when applied thus shifts the crank arm 50 to and holds it in its position shown in Fig. 7 against the force of a spring |54. 'I'he spring |54 as shown in Fig. 6 is in the form of a circular piece of flat spring metal having an eccentric opening therein and the outer portion thereof is secured at |55 to the flange ||5. Thus the inner portion of the spring |54 engages the lower edge of the inwardly extending arrn |50b of the crank |50 to exert an upward force thereon.

The inwardly extending arm |50'J of the crank arm |50 is provided with a hook-shaped end portion which enters an opening |51 in the attened upper portion of the plunger |30. When the left hand ribbon spool l 22 is in place as shown in Fig. 7 this hook-shaped portion held in its lower position where the upper edge thereof is spaced downward from the upper end wail of the opening |51 asuicient distance to allow the plunger |30 to move downward under control of the crank arm |35 in the normal manner to reverse the direction of the feed of the of the arm |51!h ig ribbon when the supply of ribbon on the left hand spool is exhausted.

However, when the left hand ribbon, spool is removed the crank arm |50 is turned by the force of the spring |54 to its position shown in Fig. 5 due to the disengagement of the hub |23 of the spool from the portion |50 of the crank arm. This movement of the crank arm |50 to its position shown in Fig. causes the hook-shaped portion of the arm |50b to engage the upper end wall of the opening |5`| in the plunger |30 and thereby hold the plunger in its upper position under the force of the spring |54. At this time the asso'- ciated crank arm |35 is no longer effective to control the associated plunger. Thus, when both of the ribbon spools are removed from the machine, only the right hand plunger |30 will be allowed to drop into cooperative relation with the spiral web |44 on the drive shaft 85, the left hand plunger being maintained in its upper position by the crank arm |50. This prevents the machine from being rendered inoperative by the locking or jamming of the shiftable drive shaft 85 as would occur if both of the plungers |30 were allowed to drop into cooperative relation with their associated spiral webs.

It will be seen that I have thus provided an improved ribbon feeding mechanism wherein locking or holding means are provided to permit the typewriting machine to be operated with both of the ribbon spools removed thereby increasing the utility and exibility of the machine. It will be clear that it is only necessary to provide this locking or holding means to coact with one of the ribbon spools, and further that such means are very simple and inexpensive in construction and yet operate to effectively and reliably hold one of the ribbon reversing members or plungers against operation when the associated spool is removed without in any manner interfering with the normal operation thereof when the ribbon spool is in place.

A further feature of the present ribbon feeding mechanism is in the arrangement of the parts to permit the interior chassis to be readily removed from the outer casing. In other words, it is desirable in the present machine to mount certain of the parts of the ribbon feeding mechanism on the outer casing while the` remainder of the parts are mounted on the removable inner chassis, and connecting means have been provided in the feeding mechanism for the ribbon which are automatically disconnected when the chassis is removed and which are automatically brought into cooperative relation when the chassis is replaced. It will further be noted that this connecting means in the feeding mechanism for the ribbon not only allows the chassis to be readily removed but also affords longitudinal movement of the ribbon reversing drive shaft with relation to the parts carried by the outer casing. Thus, this particular connecting means has a definite cooperation with the ribbon reversing mechanism including the locking or holding means and has a particular value and significance when used in combination therewith.

Various changes may be made in the construction, and certain features thereof may be omitted without departing from my invention as it is defined in the accompanying claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a typewriting or like machine, the combination of an exterior frame, a chassis removably mounted in said frame,- a carriage mounted for movement on said exterior frame, ribbon driving means mounted on said exterior frame and operatively connected with said carriage, ribbon spool carrying means mounted on said chassis, and means for operatively connecting -said ribbon driving means on said exterior frame with said ribbon spool carrying means on said chassis, said means including a rotatable part, on said chassis, a rotatable part on said exterior frame disposed in axial alignment with said rotatable part on the chassis, and cooperating members on said rotatable parts which are engageable at points spaced outwardly Ifrom the periphery of said rotatable part on the chassis and arranged to be automatically disengaged when said chassis is removed from said exterior frame and automatically reengaged when said chassis is replaced.

2. In a typewriting or like machine. the combination of an exterior frame, a chassis removably mounted in said frame, ribbon driving means mounted in said exterior frame, a ribbon reversing shaft mounted in said chassis for shifting movements in the direction of its length, and means for operatively connecting said ribbon driving means with said ribbon reversing shaft regardless of the shifted position thereof, said means including cooperative engageable parts in axial alignment on said ribbon driving means and said ribbon reversing shaft which are automatically disengaged when said chassis is removed from said exterior frame and automatically reengaged when said chassis is replaced.

3. In a typewriting or like machine, the combination of an exterior frame, a chassis removably mounted in said frame. a ribbon reversing shaft mounted in said chassis for shifting movements in the direction of its length, ribbon driving means mounted in said exterior frame including arotatable part disposed in axial alignment with said reversing shaft, and means for operatively connecting said rotatable part with said reversing shaft regardless of the shifted position thereof, said means including a pin carried by said rotatable part in spaced parallel relation to the axis thereof and an arm carried by said reversing shaft in contactive relation to the side of said pin to permit the removal of said chassis from said exterior frame.

4. In a typewriting or like machine, the combination of a ribbon carrying member, mounting means for removably holding said ribbon carrying member, drive means shiftable into and out of operative relation with said mounting means, shifting means Iforv said drive means including a shifting member movable to and from effective position, a rst control means carried by said mounting means and coacting with said ribbon carrying member and said shifting member to allow the latter to move to effective position only when the ribbon carrying member is in place on the mounting means, a second control means carried by said mounting means and coacting with the ribbon on said carrying member to move from normal position when the supply of ribbon is substantially exhausted, and means connecting said shifting member with said second control means to hold the shifting member from effective position when the second control means is in normal position and to afford movement of the second control means when the shifting member is held from eective position by the iirst control means.

5.l In a typewriting or like machine, the combination of a ribbon carrying member, mounting means for removably holding said ribbon carrying member, drive means shiftable into and out of operative relation with said mounting means, shitting means for said drive means including a plunger movable by gravity to effective position,

a Ibell crank pivotally mounted on said mounting means and having one arm-thereof coacting with said ribbon carrying member and the other arm thereof coacting with said plunger to allow the latter to move to effective Iposition only when the ribbon carrying member is in place on said mounting means, control means carried by said mounting means to coact with the ribbon on said mounting member and move from holding position when the supply of ribbon is /rubstantially exhausted, and connecting means including an 10 eifective position by said bell crank.

RUSSELL G. THOMPSON.

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