US2940577A

US2940577A - Teletype machine ribbon control

Info

Publication number: US2940577A
Application number: US794665A
Authority: US
Inventors: Marion I Smallwood
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-02-20
Filing date: 1959-02-20
Publication date: 1960-06-14
Anticipated expiration: 1977-06-14

Description

June 14, 1960 M. 1. sMALLwooD TELETYPE MACHINE RIBBON CONTROL Filed Feb. 20, 1959 .i G.- l

so ff A ryA/5r 'rELE'rYPE MAcHiNE RIBBON CONTROL Marion I. Smallwo'od, 1345 Campbell Road,

klahoma City, Okla.

Filed Feb. 20, 1959, Ser. N0. 794,665

Claims. (Cl. 19715S) This invention relates generally to improvements in teletypewriter machines, and more particularly, to means for controlling the movement of the ribbon of a teletypewriter machine to utilize the maximum surface area of the ribbon.

In present day teletypewriter machines the ribbon is supported on two rolls and extends through a ribbon carrier positioned between the rolls. One of the 'rolls is driven for lengthwise movement of the ribbon until substantially the entire length of the ribbon has passed through the ribbon carrier; whereupon the opposite roli is driven to reverse the lengthwise direction of movement of the ribbon through the carrier. The ribbon carrier is reciprocated vertically during operation of the teletypewriter machine for raising the ribbon to a printing level when a key is depressed, such that the type will strike the ribbon and form a letter or symbol. When the teletypewriter key is released to lower the type, the ribbon carrier moves downwardly to expose the letter or symbol previously typed. Although the ribbon is of sufficient width to accommodate at least two rows of type, the ribbon carrier in a present day machine is raised only sutliciently that the top half portion of the ribbon is contacted by the type and the lower half portion of the ribbon is normally unused. As a result, the service life of teletypewriter ribbons is limited, which in turn requires frequent replacement of the ribbons.

The ribbon rolls of a present day teletypewriter machine may be turned over, such that the unused half portion of a ribbon may be used in a subsequent operation of the machine. However, the reversal or turning over of the ribbon rolls is a time consuming and messy operation, and is normally not performed in most organizations using any appreciable number of teletypewriter machines.

The present invention contemplates the use of both the upper and lower half portions of a teletypewriter ribbon, without the necessity of changing the ribbon rolls. This invention contemplates a novel lever engaged by the mechanism used in driving the ribbon lengthwise, for pivotal movement of the lever upon each reversal in the lengthwise direction of movement of the ribbon. The lever is so positioned on a teletypewriter machine as to limit the upward movement of the ribbon during lengthwise movement of the ribbon in one direction, such that one 'half portion of the ribbon will be raised to a printing level for contact'by the type during lengthwise movement of the ribbon in one direction, and the ribbon will be moved to such a height that the other half portion will be contacted by the type during movement of the ribbon in an opposite direction. The present mechanism is completely automatic in operation, such that the maximum surface area of a ribbon will be used without any manipulations of the ribbon by the teletypewriter operator.

An important object of this invention is to decrease the cost of operating teletypewriter machines.

Another object of this invention is to utilize the maximum surface area of a teletypewriter ribbon, without the aired States Patent O necessity of interrupting the operation of a teletypewriter machine.

Another object of this invention is to utilize the maximum surface area of a teletypewriter ribbon, without the necessity of interrupting the operation of a teletypewriter machine.

A further object of this invention is to minimize the time during which teletypewriter machines are out 'of operation.

A still further and more speciiic object of this invention is to utilize one half portion of a teletypewriter ribbon during lengthwise movement of the ribbon in one direction and to utilize the other half portion of the -ribbon during lengthwise movement of the ribbon in an opposite direction.

Another object of this invention is to adaptt an existing teletypewriter machine for use of both the upper and lower half portions of a ribbon, with a minimum of change or alteration of the existing teletypewriter machine structure.

Other objects and advantages of the invention will be evident from the following detailed description, when read in conjunction with the accompanying drawings which illustrate my invention.

in the drawings:

Figure 1 is a side elevational view of a 'portion of the type basket of a teletypewriter machine incorporating 'the present invention, wherein the existing structure is shown in dashed lines and the new structure is shown in solid lines.

Figure 2 is a bottom view of the type basket of a teletypewriter machine incorporating the present invention, wherein the existing structure is again shown in dashed lines and the new structure is shown in solid lines.

Figure 3 is a View similar to Fig. 2 illustrating a second position of the lever of the present invention.

Figure 4 is an end view of the eccentric bolt used for supporting the lever shown in Figs. 1, 2 and 3. Y

in the detailed description of the present invention, only those portions of an existing teletypewriter ymachine which cooperate with the new structure will be described, to more clearly illustrate the invention. Referring to Fig. l, it will be observed that the ribbon 6 of a teletypewriter machine is extendedrthrough a ribbon carrier 8 between the ribbon rolls (not shown). The ribbon carrier 8 lis in turn pivotally connected to a ribbon oscillator 10 pivotally supported by a shouldered screw -12 and biased by a spring 14 for upward pivotal movement of the outer end of the oscillator about the screw 12. An extension 16 is secured by a suitable bolt 18 to the ribbon oscillator 1i? and extends generally vertically for pivoting the oscillator 10 about the screw 12 and raising and lowering the ribbon carrier 8. The lower end portion of the oscillator extension 16 extends into the path of movement of a pull bar bail plunger 20, as more clearly shown in Fig. 2.

The plunger 2.4i is mounted in the lower portion of a teletypewriter machine and reciprocates fore and aft Vtl'rrough suitable rollers 22 during operation of the-teletypewriter machine. A shoulder 24 on the pull vbar bail plunger 20 contacts the lower end portion of the oscillator extension 16 during forward movement of the plunger for pivoting the ribbon oscillator 10 in aV clockwise direction (as viewed in Fig. l) and lowering the .ribbonrcarrier 8. plunger 20 is operated by a vconventional mechanism (not shown) for a rearward vmovement when a key (not shown) on the teletypewriter machine is depressed and for forward movement when the key is released. In' a normal operation of a teletypewriter machine, the shoulder 24 of the plunger 20 is moved rearwardly to a position behind a stationary Vframe cross bar 25 when a key of the machine is depressed, such that the .such-,a position that'the upper halfportion of the ribbon Vtifisfcontacted by the type'when the plunger 20 is in its rearmostposition and the Yextension 16 is in contact with the cross bar 25, as illustrated in Fig. 3. jAsthe plunger .20 moves forwardly, theshoulder 24 contacts the oscillaftorJextensionV 16 andzlowers the carrier 8 andribbon 6 to Y f4 located bolt holes for reception of the screw 12 and bolt 18.for.relocating the outer end portion of the oscillator.

. The new oscillator 60 is positioned with respect to the a Ylevel below the printing level, such that the operator of Y themachine. maj/'observe the material which has been typed.: The detailed iconstructionand operation of the mechanismzused for moving the plunger fore and aft vfrms'no parlt of the present invention and is therefore tnotrdescribed in detail-herein.

' The ribbon 6 is driven lengthwise bye.` standard drive Y systemwhichincludes a` ribbon `rfeedshaftY 28 extending transverselyacross the teletypewriter machine rearwardly ofitheplunger 20, as illustrated Yin Figs. Zand 3. The ribbon feed shaft Y28 isfshifted lengthwise Vas illustratedV by the positions in Figs. 2 and 3 to alternately engage bevel gears 30 and 32 for driving the ribbon 6 lengthwise in opposite directions.. In other words, when the ribbon feed shaft`28'is in such a'position to engagethe bevel gear Y 30 as in Fig. 2, the ribbon 6 is moved lengthwise through the ribbon carrier 8 in one direction. i When the shaft 28 .isfshifted inits opposite position to engage the bevelV gear 32 las'. shown in`Fig. 3, the ribbon 6 is driven lengthwise in an opposite direction. The shifting of the ribbon feed jshaft 28 is automatically performed when ,theY ribbon 6 hasV been moved throughout substantially its entire length throughV the carrier 8. It will'also'be observed in Figs. 2'ar1d3jthat a Vdetent 34 is formedar'ound a medial portion of the'ribbon feed shaft 28 which normally cooperates with a spring 36 for holding the shaft 28 in its shifted positions.AV

InY accordance Awith the presentinvention, a lever 40 is vpivotally secured acrossrthe lower portion of the'teletype- 'writer machine type basket to position the rearward end V42'oftlie lever adjacent'the detent V34 of the ribbon feed Y'shaft 28`and the forward' end 44 of lthe lever adjacent the Ycross rbar'25 above the pathof'movementof theshoulder ment 'of the- 'shouldn-524 of the plunger 27).

the Vpivotpointofthe lever, such that the rear end 42 of Vthe lever isurged into contact withthe detent 34 and the forward Vend 44* of the'Y lever is Vurged vaway from the 'plunger 20.` It will also be Vobserved in Figs.2 and 3 that ainger is extended transversely from-the forward end 244: ofthe lever f4()` for movement in and out of the pathof `rnovement'ofthe oscillatorextension 16,' as will be moreV fully hereinafter set forth. .Y 1

.Y VThe leverY 40 is pivotally secured 'to the cross bar 46 Y gby a novelbolt-SZ shown in detail in'Fig. 4. The lbolt V52 is provided with an eccentric shoulder 54 adjacent the head of the'bolt which is tted in a complementary aperture 56 `(Fig. 1) extending .transversely through thelever V40.V "VIt willVV thus be apparent that when the bolt 52 is .-turned, the lever 40 is shifted fore and aft -to positionthe fore-and aft location of theV lever finger Sil. This adjustvment in turn controlsY the height towhich the ribbon6 is Y raised when the linger 50 is in the path of movement of the extension Y16, as will be described.

Y The presentinvention also contemplates the replacement of the existing ribbon oscillator V1l) with a new rib! Ybon oscillator"60.shaped in substantially the same manner asthe existing oscillator 10, but having slightly dilferently extension 16 such thatrwhenl the bar 25 stops the extension 16, the ribbon 6 will be raised higher than when using the existing oscillator 10. The increase in height is substantially equal to the height of the type used in a teletypewriter machine. In other words, when the extension 16 moves into-contact with bar 25,.the existing oscillator 10 raises the ribbon 6 to such a height that the type will contact the upper half portion ofthe ribbon; whereas the oscillator 60 will raise the ribbon 6 to such a height that the type will contact the lower half por-tion of the ribbon. It will be apparent that the bolt holes Yign the existing oscillator 10 may be changed to accomplish this result, although l prefer to replace the oscillator V10 with'the new oscillator 60 tovminimize the alteration required in an Yexisting teletypewriter machine by the mechanic or operator installing the present invention. y ,Y

In Y,operation of a teletypewriter machine` vhaving the present invention incorporatedV therein`,ilet it first be assumed that the ribbon feed shaft 28 is in its left hand posi- Ytion as illustrated in Fig. 3 and the ribbon 6 is being driven in one direction throughv the Vribbon carrier 8. In this position of the shaft 28, the detent 34 will be moved to Vthe left of the lever 40 and the spring 48 will have moved 4boncarrier 8'is raised to wherethe lower half Yportion ofthe ribbon 6 is at printing level as indicated by the arrow 26 shown in Fig.r l. As the key onthe teletype- Y.w'riteiimachine is released, the plunger 20 is moved forwardly until the shoulder V24 of the Yplunger engages and .forces the oscillator V'extension 16 in'a'clockwise direction to theV position shownV in Fig.' l. AThis movement of the extension 16 pivots the oscillator 60 back downwardly to such apositonthat theribbon is moved to below the printing level and the operator ofthe machine can observe the typed material.YV Vl `When'the ribbon feed shaft l28 is Vshifted tothe right to engage the bevel gear VV30 as illustrated inV Fig. 2, the

Vvdetent 34 contacts the rear Vend 142 Yof the lever '.40 kand fmoves`the iiger'50of-.the lever intothepathrof movevment of theext'ensionl'l against the actionofthespring 48. v It will be observedinFigl that thenger 50 will Y then'rbe positioned slightly forward of the cross kbar 25.

feed shaft Z8-is again shift It may also be noted thatgthe lever 40 willV be shifted when noY key on the teletypewriter machine isldepressed, such that the Vplunger 20 willbe' in` its forward position as shown in Fig. 1,'and the linger 50 may move freely into the path of movement of'theiex'tension v16 without inter- Y Vferringv with eitherthe plungerk 20 or .thetextension 16.

-to theY position shown in Fig. .-2.1 However, prior to reach- ;ing the cross bar 25, the extension 16'will contact the When akey onthe teletypewriterniachine is,v then depressedythe plunger ,20,will again be moved rearwardly linger 50 of Ythe-levend() and 'will prevent any further upward Vmovement of the ribbon carrier38 and ribbon 6. In this position of the exte'nsonr16,:tl:le ribbon 6 will be raised `to such a height :that the top half'portion'of the vribbon at` printinglcvel Arand will be contacted Vby the move forwardly and the shoulder 24 willbe moved into contact with'the'lextension 16` toagain'pivot the extension 16 clockwise and lower the ribbon 6 tobelow printinglevel. 'Ihis' operationfisf continuedV u ntil the Vribbon eid-lengthwise andthe lever 40 is pvoted in a clockwise direction (when viewed as in Figs. 2 and 3) to remove the iinger 50 from the path of movement of the extension 16.

Minor fore and aft adjustments of the lever 40 may be provided by rotation of bolt 52, as previously indicated. It will be apparent that the fore and aft positions of the lever 40 will control the height to which the ribbon 6 is raised when the linger S is in the path of movement of the extension 16. Thus, the lever 40 may be adjusted to assure that the ribbon 6 will be moved to the desired position and the maximum surface area of the ribbon 6 will be used.

From the foregoing it will be apparent that the present invention will materially extend the service life of teletypewriter ribbons and will minimize the down time of teletypewriter machines presently required for changing ribbons. The present mechanism is automatically operated to utilize one half of the ribbon when the ribbon is moved in one direction through the ribbon carrier, and the other half of the ribbon is used during movement of the ribbon in the opposite direction. It will be further apparent that the present mechanism is extremely simple in construction and will require a minimum alteration of an existing teletypewriter machine.

Changes may be made in the combination and arrangement of parts or elements as heretofore set forth in the specication and shown in the drawings, it being understood that changes may be made in the precise embodiment disclosed without departing from the spirit and scope of the invention as defined in the following claims.

l claim:

l. in a teletypewriter machine having a ribbon, a ribbon carrier for moving a portion of the ribbon upwardly during printing and downwardly between printings, means for moving the ribbon lengthwise through the ribbon carrier rst in one direction and then in an opposite direction, a ribbon oscillator supporting the ribbon carrier and being spring biased to raise the ribbon, van extension on the ribbon oscillator arranged to contact a stationary cross bar of the machine and limit upward movement of the ribbon, and a pull bar bail plunger movable between a rst position and a second position, said plunger being arranged in the path of movement of the oscillator extension for contacting said extension and lowering the ribbon upon movement toward said rst position and releasing said extension for the upward movement of the ribbon in said second position; the improvement which comprises a lever secured to the machine for movement in and out of the path of movement of the oscillator extension between Vsaid first position of the pull bar bail plunger 'and said stationary cross bar, said lever being extended intoengagement with the ribbon moving means for movement upon a reversal in the direction of lengthwise movement of the ribbon, whereby the ribbon is raised to a lower level when the ribbon is moving in one direction than when moving in the opposite direction.

2. A teletypewriter machine as dened in claim l wherein the means for moving the ribbon lengthwise includes a ribbon feed shaft having a detent thereon, said ribbon feed `shaft being shiftable lengthwise to reverse the direction of movement of the ribbon, and wherein vao said lever is pivotally supported on the machine and is spring-loaded for pivotal movement in one direction to extend into contact with one side of the ribbon feed shaft detent for pivotal movement upon lengthwise shifting or" the ribbon feed shaft.

3. In a teletypewriter machine having a ribbon, means for moving a portion of the ribbon upwardly to a printing level during printing and downwardly below printing level between printings, said means including a generally vertically extending ribbon oscillator extension supported for pivotal movement and spring biased in a direction for raising the ribbon, said extension being movable into contact with a stationary cross bar on the machine for limiting the upward movement of the ribbon, a pull bail bar plunger movable fore and aft on the machine in the plane of movement of the ribbon oscillator extension for lowering the ribbon upon forward movement and releasing said extension for raising of the ribbon upon rearward movement, and said machine having drive means for moving the ribbon lengthwise lirst in one direction and then in an opposite direction, said drive means including a ribbon feed shaft rotatably mounted transversely across the machine aft of said plunger and shiftable lengthwise for reversing the lengthwise direction of movement of the ribbon and having a detent thereon; the improvement which comprises a lever having a front end and a rear end and a fingerY extending transversely from the forward end thereof, means for pivotally supporting the lever on the machine for movement in a horizontal plane with the rear end thereof adjacent said detent, and a spring anchored to the lever and to the machine urging the rear end of the lever against said detent for pivotal movement of the lever upon each reversal in the lengthwise direction of movement of the ribbon, the forward end of the lever being positioned for movement of said nger in and out of the path of movement of the oscillator extension forward of said stationary cross bar on the machine to limit the upward movement of the ribbon during lengthwise movement of the ribbon in one direction.

4. A teletypewriter machine as defined in claim 3 wherein said means for pivotally supporting the lever comprises a bolt extending through an aperture in the lever, said bolt having an eccentric shoulder thereon positioned within said aperture for adjusting the fore and aft position of the lever and adjusting the height to which the ribbon is raised when said nger is moved into the path of movement of the oscillator extension.

5. A teletypewriter machine as defined in claim 3 characterized further to include a ribbon oscillator connected to said extension positioned to raise the lower half of the ribbon to printing level when said linger on the lever is out of the path of movement of said extension and to raise the upper half of the ribbon to printing level when said nger is in the path of movement of said extension.

Pool Jan. 25, 1910 Bordonaro Mar. 2, 1943