US2872016A - Ribbon winding device for typewriters and the like - Google Patents

Description

A. H. SHARPE Feb. 3, 1959 RIBBON WINDING DEVICE FOR TYPEWRITERS AND THE LIKE Filed Dec. 29, 1954 5 Sheets-Sheet 1 m/vewroe ARTHUR fair/m 5 6 ATTORNEY A. H. SHARPE 2,872,016

ERS AND THE LIKE Feb. 3, 1959 RIBBON WINDING DEVICE FOR TYPEWRIT 3 Sheets-Sheet 2 Filed Dec; 29, 1954 @mk w.

. INVENTOR. ARTHUR H .SHARPE ATTORNEY A. H. sHARPE 2,872,016

RIBBON WINDING DEVICE FOR TYPEWRITERS, AND THE LIKE Feb. 3, 1959 3 SheetS -Sheet 5 Filed Dec. 29, 1954 ATTORNEY INVENTOE ARTHUR H SHARPE Z6 27 7; g a: B) 4.

United States Patent RIBBON WINDING DEVKCE FOR TYPEWRITERS AND THE LIKE Arthur H. Sharpe, West Hartford, Conn., assignor to Underwood Corporation, New York, N. Y., a corporation of Delaware Application December 29, 1954, Serial No. 478,307

9 Claims. (Cl. 197-151) This invention relates to typewriting and like machines, especially electric typewriters, and more particularly to an improved means for winding the inked ribbon thereof from one spool to the other.

Typewriters and other printing type business machines are commonly provided with an inked ribbon adapted to be pressed by the types against a work sheet for producing a legible record. When in use, the ribbon is partially wound on two spools or reels mounted on opposite sides of the printing point with a portion between the two spools extending slightly below the printing point and moved upward to printing position upon each actuation of a type. As the machine is operated, the ribbon is moved in small increments back and forth across the printing point, becoming wound first on one spool and then on the other. When it is desired to change ribbons, the ribbon in use is customarily wound manually onto one of the spools, either by directly turning he spool by hand or by operating a special winding knob, and the full spool is then replaced with a new full spool. It frequently happens that the need for a new ribbon arises or is noticed at a time when a good portion thereof is wound on each spool so that the manual Winding or rewinding of the ribbon onto one spool is a time consuming and irksome operation.

It is the primary object of this invention to provide an improved power driven means for rapidly winding the ribbon of a typewriter or the like onto one of the ribbon spools whenever it is desired to change ribbons.

It is a further object of the invention to provide a power driven ribbon winding device which may be readily incorporated in existing machines without interfering with the usual ribbon feeding means thereof.

These and other objects, features and advantages thereof will become readily apparent as the description of a preferred embodiment of the invention proceeds.

, Referring now to the drawings:

Figure l is a side elevational view of a device constructed in accordance with the present invention and showing same incorporated in an electric typewriter,

Figure 2 is a view similar to Figure 1 and showing the parts in ribbon winding position, 1

. Figure 3 is a side elevational view of a portion of the device showing how the ribbon winding operation may be manually discontinued,

Figure 4 is a perspective view showing the device and a portion of the ribbon feeding means,

Figure 5 is a plan view of a portion of the ribbon feeding means of the typewriter,

Figure 6 is a simplified wiring diagram,

Figure 7 is a view partially in section and partially in front elevation of the ribbon feeding means of the typewriter and showing means operated by the ribbon feeding means to automatically disengage the ribbon winding device when the ribbon becomes fully wound on one spool, and

Figure 8 is a perspective view showing means for dis- 'ice abling the operation of certain parts of the machine during operation of the device of the present invention.

The invention is shown embodied in the well-known Underwood electric typewriter but it will be apparent that certain features thereof may readily be incorporated in other electric typewriters as well as in printing machines other than typewriters.

The main frame plates of the machine, between which most of the working mechanisms are mounted, are indicated in Figure 7 at 10 and 11 and it will be observed that said plates are provided with bent over portions at the top for supporting ribbon spool carriers 12 and 13. The ribbon 14 is secured at its opposite ends to ribbon spools 15, see Figure 4, which are keyed to the carriers 12 and 13 and the portion of the ribbon between the two spools passes around suitable guides and through a ribbon vibrator 16. As is known, it is the portion of the ribbon adjacent the ribbon vibrator which is used for making the impressions and upon each actuation of a type bar the ribbon vibrator is raised to position the ribbon between the type and a work sheet wound around a letter feed platen 17.

As shown in Figure 7, the ribbon spool carriers 12 and 13 are secured to cylindrical shafts 18 and 19 respectively guided at their upper ends in the bent over portions of the side plates and rotatably mounted near their lower ends in suitable brackets 20 and 21. Gears 22 and 23 are secured to the lower ends of the shafts 18 and 19 respectively and said gears are alternately meshed with gears 24 and 25 secured to a ribbon winding shaft 26 rotatably mounted in the brackets 21) and 21. A fine toothed Wheel 27 is secured to the shaft 26 and, as shown in Figures 1 and 2, a pivotally mounted holding pawl 28 and an actuating pawl 29 are normally held in engagement with the teeth of said wheel by means of a light spring 30 extending between said pawls. Upon each operation of a type action, the pawl 29 is slightly raised and lowered to thereby slowly rotate the toothed wheel 27 and the shaft 26 to which said wheel is secured. As the shaft 26 is rotated, one or the other of the cylindrical shafts 18 and 19 is rotated, depending upon which pair of gears 22 and 24 or 23 and 25 are meshed, to thereby drive the ribbon in one direction or the other.

The shaft 26 is automatically shifted endwise in a manner explained in the patent to Going No. 1,242,173 to disengage one of the pairs of gears 22, 24 or 23, 25 and engage the other pair to thereby reverse the direction of ribbon feed when said ribbon becomes fully unwound from one of the spools 15. A knob 31 is also provided on an end of the shaft 26, externally of the machine so that said shaft may be manually shifted or manually rotated whenever desired. Prior to the present invention, the knob 31 has been operated to wind the ribbon fully onto one spool whenever it was desired to change ribbons.

As shown in Figure 5 a suitable detent means may be provided for holding the shaft 26 in its shifted positions; The particular detent means illustrated comprises a shifter collar 32 secured to one end of the shaft 26 and an overthrow linkage 33 and 34 having a pin 35 engaged with said collar. The link 33 is pivoted at one end to a suitable bracket and at the other end to one end of the link 34, the opposite end of which is pivoted to an arm 36 urged by a spring 37 to hold the linkage 33 and 34 in one over center position or the other.

Referring now particularly to Figures 1, 2 and 4, the usual electric motor of the machine is indicated at 38 and said motor drives a shaft 39 through a pair of toothed pulleys 4i) and 41 and a toothed drive belt 42. The type actions and certain other working mechanisms of the machine are driven by the shaft 39 in the usual Wellknown manner.

Spaced outwardly from the frame plate by a pair of spacer plates is a bracket plate 43 carrying a non rotatable stub shaft 44 upon which is pivotally mounted an arm 45. Shafts 46 and 47 are secured to the arm and rotatably mounted on said shafts are engaged friction rollers 48 and 49. By swinging the arm 45 clockwise from the position shown in Figure 1 to the position shown in Figure 2, in a manner presently to be explained, the roller 48 is brought into driving engagement with the top of the belt 42 and the roller 49 is engaged with the toothed wheel 27.

A lever 50 is swingably mounted on the stub shaft 44 adjacent the arm 45. A spring 51 urges the lever 50 in a counterclockwise direction against a stop provided by a bent over portion of the bracket plate 43 and an ear 52 on the lower end of said lever engages an edge of the arm 45 to hold said arm in the Figure 1 position with the roller 48 disengaged from the belt 42. Pivotally connected at 53 to the upper end of lever 50 is an operating member 54 having a finger piece 55 at its upper end and a tab 56 at its lower end. The tab 56 is aligned with a collar 57 provided on the stub shaft 44 and lies between said collar and on upstanding arm 58 of a latch member 59. The latch member 59 is pivotally mounted on the bracket plate 43 at 60 and is provided with a latching shoulder 61 adapted to engage a square stud 62 projecting inwardly from the lever 50. A spring 63 extending between the arm 58 and the member 54 normally holds a portion of the latch member 59 against the square stud 62.

When the finger piece 55 is pressed toward the platen, the operating member 54 swings the lever 50 from the Figure 1 position to the Figure 2 position, said operating member being prevented from rotating clockwise on the pivot 53 by the engagement of its tab 56 with the collar 57. As the lever 50 swings to the Figure 2 position, a

- spring 64 extending between the tab 52 and the arm 45 moves said arm to the Figure 2 position to engage the roller 48 with the top of the belt 42 and the roller 49 with the toothed wheel 27. When the arm 45 reaches the Figure 2 position, the spring 63 snaps the latch member 59 in a counterclockwise direction to engage the shoulder 61 of said latch member with an edge of the square stud 62 to hold the arm 45 in active position.

The latch member 59 is provided with a substantially horizontally extending arm 65 the end of which, when said latch member is in the Figure 2 position, lies in the path of movement of an upper cammed end of a member 66, best shown in Figures 4 and 7. The member 66 is pivotally mounted on a screw stud 67 secured in an angle bracket 68 provided on the bracket plate 43 and the lower end of said member is provided with a pair of arms the ends of which lie closely adjacent opposite sides of the toothed wheel 27. When the shaft 26 to which the toothed wheel 27 is secured is shifted endwise as aforesaid, the member 66 is rocked and the upper end thereof cams the latch member 59 clockwise to disengage the shoulder 61 from the stud 62, thus permitting the spring 51 to restore the lever 50 and arm 45 to the Figure 1 position.

An arm 69 is secured to the shaft 46 and when the arm 45 is moved to the Figure 2 position, a cam end 70 of the arm 69 engages the pawls 28 and 29 and rocks said pawls out of engagement with the toothed wheel 27.

The finger piece 55 of the operating member 54 lies adjacent the ribbon spool carrier 12 and beneath a swingable door 71, see Figures I and 8, of the cover 72 of the machine. The door 71 is normally closed to protect the operator from injury by the motor driven parts of the machine and to protect the working mechanisms against harmful interference by the operator. Since it is normally not desirable to have the motor run-- ning when thedoor 71- is open, means is provided to prevent the opening of said door when the-main-motorswitch is closed, that is, when a switch operating knob 73 shown in Figure 8 is in on position. The details of the door locking mechanism are not a part of the present invention and therefore need not be explained in this application but same may be as fully explained in the patent to Helmond, No. 2,366,107. When the door 7i is open it is in the path of movement of the carriage and means is therefore provided to prevent operation of either the tabulating or carriage return mechanisms when the switch operating knob 73 is in off position, which is the only time that said door can be open. Such mechanism is fully explained in the patent to Sagner, No. 2,655,245 and the explanation need not be repeated herein. Suifice it to say that there is a lever 74, see Figure 8, pivotally mounted at 75 and that said lever must be swung counterclockwise about its pivot in order for the carriage return or tabulating mechanisms to become effective and when the main switch operating knob is in off position an end 76 of a rod 77 is moved to closely overlie the lever 74 so that said lever cannot move counterclockwise.

Since the door 71 must be open in order to change the ribbon and in order to operate the ribbon winding mechanism of this invention and since the main motor switch is open at that time, a second motor switch is provided for energizing the motor during ribbon winding operations. Such switch is indicated in Figures 1 and 4 at 78 and is entitled Winding Switch in the wiring diagram from which it will be observed that the two motor switches are wired in a parallel circuit so that when either one is closed the motor will be energized. The switch 78 is connected by a rod 79 to the tab 52 of the lever 50 so that when the lever 50 is swung to the Figure 2 position to engage the rollers 48 and 49 with the belt 42 and toothed wheel 27 respectively, as aforesaid, the switch 78 will be closed and the motor 38 will start operating.

Operation When it is desired to change the ribbon, the operator turns the main switch operating knob 73 to off position, opens the door 71, and observes which of the two spools has the most ribbon wound on it. The knob 31 may then be pushed or pulled to shift the ribbon winding shaft 26 to the position where the ribbon will be winding onto the spool which already has the most ribbon. The finger piece 55 is then moved rearwardly toward the platen to engage the roller 48 with the drive belt 42 and the roller 49 with the toothed wheel 27. This latter operation closes the winding switch 78 and reenergizes the motor so that the belt 42 drives toothed wheel 27 through the rollers 48 and 49. As the wheel 27 rotates, it of course rotates the shaft 26 and winds the ribbon as aforesaid.

The Winding operation will be automatically discontinued when the ribbon becomes fully unwound from one of the spools because of the shifting of the shaft 26 and the consequent rocking of the member 66 to disengage the latch member 59 from the square stud 62 of the lever 50, as previously explained. The operator may discontinue the winding operation at any time by merely pulling forward on the finger piece 55 so that the tab 56 of the operating member 54 strikes the upstanding arm of the latch member 59 and disengages said latch member from the stud 62. Of course, it is not necessary for the operator to observe which spool has the most ribbon on it or to move the knob 31, because merely by operating the finger piece 55 the ribbon will be wound by power onto which ever spool it was winding onto at the time,v

but timemay be saved by causing the ribbon to become fully wound on the spool which already has the most ribbon on it. When the arm 45 is moved to position to cause power winding of the ribbon, the arm 69' disengages the usual ribbon feeding pawls 23 and' 29 so that they donut ratchet over the teeth of the-wheel27.

Even though the motor is running during the ribbon Winding operation there is no possibility of the carriage being accidently tabulated or returned because the main switch operating knob has been turned to off position to thereby cause the end 76 of rod 77 to render the tabulating and carriage return mechanisms ineffective.

Having thus described a preferred embodiment of the invention, what is claimed is:

1. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a printing point and feedable in small increments back and forth across the printing point during typing operations to become wound first on one spool and then the other; ribbon feeding means operable upon each actuation of a type action to impart a small increment of movement to the ribbon, said feeding means comprising a toothed wheel and a feed pawl spring urged into engagement therewith, power means for driving the various parts of the machine, selectively operable means for drivingly connecting said power means to said toothed wheel for continuously winding the ribbon and means operable by said selectively operable means to disengage said feed pawl from said toothed wheel.

2. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a print ing point and feedable in small increments back and forth across the printing point during typing operations to become wound first on one spool and then the other; an electric motor and a switch for connecting said motor to a power source, ribbon winding means comprising a rotatable shaft, mechanism spring urged to an inactive position but selectively movable to an active position, said mechanism in active position drivingly connecting said shaft to said motor, means operable by said mechanism to close said switch when said mechanism is moved to active position, latch means for holding said mechanism in active position and means automatically operable when the ribbon beomes completely unwound from one spool to release said latch means and permit said mechanism to return to inactive position.

3. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a printing point and feedable in small increments back and forth across the printing point during typing operations to become wound first on one spool and then the other; ribbon feeding means operable upon each actuation of a type action and comprising a toothed wheel and a feed pawl spring urged into engagement therewith, means automatically reversing the direction of ribbon feed when the ribbon becomes fully unwound from either one of the spools, power means for driving the various parts of the machine, selectively operable means for drivingly connecting said power means to said toothed wheel for continuously winding the ribbon, means operable by said selectively operable means for disengaging said feed pawl from said toothed wheel, latch means for holding said selectively operable means in operated position and means operable by the means automatically reversing the direction of ribbon feed to release said latch means.

4. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a printing point and feedable in small increments back and forth across the printing point during typing operations to become wound first on one spool and then the other; ribbon feeding means operable upon each actuation of a type action and comprising a toothed wheel and a feed pawl spring urged into engagement therewith, means automatically reversing the direction of ribbon feed when the ribbon becomes fully unwound from either one of the spools, a motor for driving the various parts of the machine, a switch for connecting said motor to a power source, selectively operable means for drivingly connecting said motor to said toothed wheel and for closing said switch, latch means for holding said selectively operable means in operated position and means operable 6 by the means automatically reversing the direction of ribbon feed to release said latch means.

5. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a printing point and feedable in small increments back and forth across the printing point during typing operations to become wound first on one spool and then the other; ribbon feeding means comprising a rotatably mounted shaft, a pair of gear members fixed to said shaft, shifting means for shifting said shaft endwise to bring one or the other of said gear members into driving engagement with one of the ribbon spools, means responsive to the complete unwinding of the ribbon from one of the spools to operate said shifting means and drivingly engage one of the gear members thereof with the spool from which the ribbon has become unwound, a toothed wheel fixed to said shaft, a feed pawl spring urged into engagement with said toothed wheel and adapted to drive said wheel through a small are upon each operation of a type action, power means for driving the various parts of the machine, selectively operable means for drivingly connecting said power means to said toothed wheel for continuous rotation of said wheel and consequent continuous winding of the ribbon, latch means for holding said selectively operable means in operated position and means operable by the endwise shifting of said shaft to release said latch means.

6. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a printing point and feedable in small increments back and forth across the printing point during typing operations to become wound first on one spool and then the other; ribbon feeding means comprising a rotatably mounted shaft, a pair of gear members fixed to said shaft, shifting means for shifting said shaft endwise to bring one or the other of said gear members into driving engagement with one of the ribbon spools, means responsive to the complete unwinding of the ribbon from one of the spools to operate said shifting means and drivingly engage one of the gear members thereof with the spool from which the ribbon has become unwound, a toothed Wheel fixed to said shaft, a feed pawl spring urged into engagement with said toothed wheelv and adapted to drive said wheel through a small are upon each operation of a type action, power means for driving the various parts of the machine, selectively operable means for drivingly connecting said power means to said toothed wheel for continuous rotation of said wheel and consequent continuous winding of the ribbon, means operable by said selectively operable means for disengaging said feed pawl from said toothed wheel, latch means for holding said selectively operable means in operated position and means operable by the endwise shifting of said shaft to release said latch means.

7. In a typewriting or like machine having a ribbon mounted upon spools located on opposite sides of a printing point and feedable in small increments in either of two directions across the printing point during typing operations to become wound first on one spool and then the other; ribbon feeding means including a ribbon-feed drive shaft unidirectionally rotated a fraction of a turn upon each actuation of a type action to impart a small increment of movement to the ribbon in either of two directions, unidirectionally operative power means for driving the various parts of the machine, a rotatingmotion transmission device normally spring urged to an inactive position but manually movable to an active position, said device in active position interconnecting rotatively said unidirectionally operative power means with said ribbon-feed drive shaft for driving it continuously, a latch means for holding said device in active position and means automatically operable when the ribbon becomes completely unwound from either of said spools to release said latch means and permit said device to return to inactive position.

8. In a typewriting 01' like machine having two ribbon spool rotating elements, each one rotatable to feed a ribbon in one of two opposite directions past a printing point, a ribbon-feed drive common to said rotating elements and adapted to impart at each typing operation to one or the other of said rotating elements a small ribbon feeding movement, said drive comprising a shaft to which either of said rotating elements is operatively connectable and which for effecting ribbon feeding movement of either of said elements is rotatable in a single direction, automatically operative means to entrain said shaft with the rotating element of that spool from which the ribbon becomes substantially exhausted, and to disentrain incidentally thereto said shaft from the other rotating element, a unidirectionally rotative power means normally operatively disconnected from said shaft, a rotating-motion transmission device to connect said power means rotatively with said shaft to rotate it continuously 8 in its ribbon-feeding direction, a manual control to men der said rotating-motion transmitting device operative and means responsive to each operation of said automatically operative entraining means to render said rotatingmotion transmitting device automatically inoperative.

9. The invention set forth in claim 8', said ribbon-feed drive comprising a toothed wheel and a pawl whereby said shaft at each typing operation receives a small ribbon feeding movement, and means to" release said pawl from said toothed wheel for each duration in which the said transmitting device is operative.

References Cited in the file of this patent UNITED STATES PATENTS

Images