US1532685A - Typewriting machine - Google Patents

Description

c. B. CORCORAN TYPEWRiTING MACHINE Filed Feb. 17, 1920 2 Sheets-Sheet 1 April 7, 1925.

lNVENTOfi AT RNEY April 7, 1925. 1,532,685

' C. B. CORCORAN TYPEWRI T ING MACHINE Filed. Feb. 17, 1920 2 Sheets-Sheet 2 FIG.2.

a MW

VENTOFF AT ORNEY.

Patented Apr. 7, 1925.

unrrnn sraras CORNELIUS B. VCORCOR-AN, orfnnw onK, -1\T.- Y., AssIeNon T0 nnnnnwoon'rrrnwarren COMPANY, on nnwronn, n. a ocnrona rron or DELAWARE.

rYrnwnrrrne MACHINE.

Application filed February 17, 1920, Serial No. 359;235.

T 0 (M whom it may concern.

Be it known that I, ConNnLrUs B. Conco- RAN, a citizen of the United States, residing in borough of the Bronx, in the county of the Bronx, city and State of New York, have invented certain new and useful Improvements in Typewriting' Machines, of

which the following is a specification.

This invention relates to ribbon-mechanism for typewriting machines, and particularly to machines of the type in which the ribbon is normally below the printing line of the platen, and is movable to a plurality of positions at the printing-line, to enable printing in different colors, in both upper and lower case. 1

The invention has for its'general object improvement in the ribbon-feed, and more particularly improvement in the feed when changing from one color to another, and from lower to upper-case type.

In the 'machines of the type above referred to, such as the Underwood, the ribbon is supported by a vibrator, and is normally held thereby below the printing line of the platen. is the type move towards the platen, the vibrator is also moved to interpose the ribbon between the typeand the platen, the usual arrangement being such that the upper stripe or field of the ribbon prints in black, and this stripe is used in printing lower-case characters. a small amount of movement of the vibrator suftices to position this stripe of the ribbon at the printing line, so that the lower-case type will strike through it. A greater movement is required to position the lower stripe or field, which is usually red, and this extra movement isprovided for by the usual color-changing mechanism. Case-shifting mechanism of any usual or well-known kind is provided to move the platen and also the ribbon-vibrator.

It has been customary to mount the rib bon-spools on vertical axes, so that the. nat ural or normal direction of ribbon-feed is horizontal and parallel with the printing line. However, as the actual unwinding of the ribbon from the loose spool takes place during the movement of the vibrator, the ribbon portions between the vibrator and the guide-roller for either spool make an angle with the normal direction of ribbon t'eed at this time, and this angle is greater Therefore,

rection of ribbon-feed, is also greatest at this time, the friction and resistance due to the bending the ribbon at the upper end of the guide-roller at the loose spool may sometimes prevent the vibrator from male ing its full movement, resulting in failure to position the ribbon with its lower or red stripe fully at the printing line. Uppercase characters may, therefore, in such cases,

have their upper portions black.

A feature of my present invention resides in so mounting the ribbon, that the pull of the vibrator to feed the ribbon occurs at the most natural angle during the operation of the vibrator. Preferably, I mount the ribbon so thatthe normal or natural feed is at an angle to the printing line of the platen, and so that the vibrator will exert a pull along said normal direction offeed at some point intermediate its normal and extreme ositions, the ribbon in normal position ying below the printing line, as is usual. This point of straight-line pull from the vibrator may be at any desired point intermediate the normal position and eXtreme'positions, and may be that corresponding substantially to the position the vibrator reaches when'p'rinting in lower case, with the upper or black stripe or strand of the ribbon at the printing line, although it is, of course, to be understood that this particular arrangement is not essential to the carrying out of my invention. When the Vibrator is in normal position, with the ribbon below the printing line, the portions of the ribbon between the vibrator and spools may form an angle with the normal direction of ribbon-feed, which is less than a straight angle, these portions forming a straight line or straight angle as the vibrator moves, passing beyond and forming an angle greater than a straight angle as the vibrator occupies other positions, such as upper-case black, lower-case red, and upper-case red. Preferably, I mount the ribbon spools on axes which are inclined slightly to the ver- At this latter case-shift tical, although other mechanical arrangements, accomplishing the purpose of my invention, may be employed.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure 1 is a side elevation of an Underwood typewriting machine, showing my improvements embodied therein.

Figure 2 is a front elevation of so much of a typewriting machine as is necessary to show my invention embodied therein; this figure showing the normal position of the ribbon and'vibrator in full lines, the dottedline position of the ribbon being that to which it is moved when the lower-case type strike the platen to print through the upper or black strand of the ribbon.

Figure 3 shows the position of the ribbon and vibrator at the instant the type strike the platen to print in lower case through the lower or red strand of the ribbon.

Figure 4c shows the position of the ribbon and vibrator at the instant the type strike the platen to print in upper case through the lower strandof the ribbon.

In the drawings, 1 indicates the frame ofthe typewriter, and pivoted at 2 in this .frame are type-levers 3, which are connected to intermediate levers 4:, pivoted at 5, to the upper ends of which levers 4 are connected type-bars 6, which are adapted, on depression of keys 7, to be driven upwardly and rearwardly a 'ainst the front face of a platen 8, mounted in a carriage 9, all of these parts being those usually found in an Underwood typewriter. The carriage, as usual, slides upon a rod 10, mounted in the frame of the typewriter at the rear, and is suitabl guided at. its forward end. tep-by-step letterfeeding movements of the carriage are accomplished, as usual, by means of a rack 11, mounted on the carriage, said rack engaging a. pinion 12, forming part of an escapement mechanism, said esca-pement mechanism including, as usual, an escape-wheel 13, controlled by escape-dogs 1 1, which are rocked by the type-bars through engagement with a universal bar 15. The type-bars, as usual, have lower-case characters 16 and uppercase characters 17 thereon. Normally, the platen is in lower position, so that when the type-keys are operated, the lower-case characters 16 will strike the printing line of the platen, and, in order to enable the uppercase characters 1'? to strik the platen, the platen is adapted to be lifted bodily upwardly, and this is accomplished, as usual, by means of a bar 18 engaging a roller 19, connected to the platen-frame. The bar 18 is adapted to be moved upwardly through the medium of a frame 20, pivoted at 21, said frame 20 being rocked by a lever 22, moved forwardly on depression of a caseshift key 23, it being usual to provide one is at an angle with the printing line of they platen. The angle at which the spools are mounted may vary slightly, to suit diiferent conditions. As the ribbon leaves each spool, it passes around a guide-roller having end flanges or heads 5 and through a guide 26, which guide-roller and guide may be of the usual and well-known construction. The ribbon is also supported at the center of the machine adjacent the platen by a ribbon-vibrator 33, which may also be of the usual type, this vibrator being adapted to be to move the ribbon from 1101 al position,

below the printing line of the platen, to a' position such that the desired stripe of ribhon, through which the printing is to be done, is positioned between the type and the platen. T have shown a mult icolor ribbon,

the upper stripe being preferably black,

I moved during the printing stroke of a key,

while the lower stripe is red, although, of

course, other colors may be used, and the usual ribbon-shifting mechanism found in the Underwood.typewriter is employed to effect a change from black to red. The spindles 24 have, at their lower ends, the usual beveled pinions 27, engaging one or another of beveled pinions 28, mounted on feed-shaft 29, said shaft acting to rotate the ribbon-spool which has its beveled 2? connected with the beveled gear 28, said rotation being effected on the return-stroke of the key by means of pawl 30 (Figure 1), engaging ratchet-teeth of a ratchet 31, mounted on said shaft 29. The ratchet 31 is retained in its moved position by a holding pawl 32.

Normally, the ribbon-vibrator 33 is in the position shown in Figure 1, with the ribbon below the printing line of the platen, as shown in full lines in said figure. It will be noted that the portion of the. ribbon be tween the guides 26 at this time is substantially horizontal, and that this horizontal portion makes an angle with those portions of the ribbon between the guides and the spool. When a type-key is struck, causing a type-bar to move towards the platen, to print the ribbon-vibrator 33 is also moved upwardly by means of. lever 34, to position the ribbon at the printing line of the platen, so that the type may strike through the ribbon. Atthe instant a type strikes the platen,

the ribbon has been positioned to substantially the dotted-line position shown in Figure 1, and it will be noted that, at this time, the stretch of ribbon on either side of the ribbon-vibrator substantially coincides with the normal direction otribbon-ieed, or, in other words, these stretches or portions of ribbon make an angle with the normal direction of ribbon-teed from each spool,

which is substantially a straight angle. This results in an easy unwinding of the ribbon from the loose spool, due to the stroke or" the vibrator. The ribbon-vibrator 33 is actuated by the lever 36L pivotally supported on the bar 18 of the shift-frame 20, the lever being provided with pins and which enter slots 37 in the side portions of a member 38 slidable transversely of the universal bar frameaecording to the position of the member 38, tne left-hand position of member 38 causing printing in the upper stripe of the ribbon and the righthand position causing printing in the lower stripe. The color-changing mechanism may F be similar to that disclosed in the patent to CoolQNo. 926,050, dated June 22, 1909.

When the case-shift mechanism has been operated to cause printing of upper-case characters, the ribbon-vibrator is moved with the platen, and, when a type-key is operated, said vibrator is given a further movement to position theribbon at the printing line, and, oi course, at this time, the stretches or portions of the ribbon between the vibrator and either spool make an angle with the normal direction of ribbon-feed which is slightly greater than a straight angle. From what has been previously said, it will, or course, be obvious that, when the ribbon-shifting mechanism is operated, to cause the lower stripe of the ribbon, usually red, to be positioned at the printing line, at the type-strokes, the rib hon-vibrator also moves the ribbon to a position such that the reaches or portions between the vibrator and each spool make an angle with the normal direction of ribbonfeed which is'also greater than a straight angle, even when printing in lower case in red. when printing inv upper case in red, the ribbon-vibrator is given its greatest movement from normal, and the direction of pull on the ribbon by the vibrator makes the greatest angle with the normal direction of ribbon-feed, but in no case is the angle so great as would be the case if the ribbonspools were mounted to rotate in a horizontal plane. Consequently, the vibrator is not in any way interfered with in making the normal direction of ribbon-feed, and

that, between this normal position and the other positions to which the ribbon is moved, the stretches of ribbon between the vibrator and spools coincide with the normal direction of ribbon-teed. This point of coincidence may be that corresponding substantially to the position the ribbon occupies when printing in lower-case "black, as this is the position to which the ribbon is most frequently moved, although, to suit certain classes of work, a different arrangement may be employed.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I

' claim Ribbon-mechanism for a typewriting ma chine in which the platen is given a caseshift movement, comprising, in combination, a ribbon-vibrator normally holding a ribbon below the printing line, ribbon-vibrator-actuating means to position the rib bon for printing therethrough in lower and upper case, a ribbon-spool at each side of the machine adjacent the platen, the axes of said ribbon-spools being in the same vertical plane, parallel to the writing line, and diverging upwardly and laterally with respect to a plane perpendicular to the axis of the platen, a flanged roller to guide the ribbon in the proper direction from the spool, and a slotted guide for the ribbon between the roller and the printing point, the inclination and elevation of each spool and the corresponding guide-roller and slotted guide being such that the friction between the roller and the ribbon, due to the lifting of the vibrator for printing in upper case, will be avoided and interference with the, proper drawing ofi of the ribbpln from the ribbon-spool will be eliminate CORNELIUS B. CORCORAN. Witnesses JENNIE P. TI-IORNE, EDITH B. LIBBEY.

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