US2616547A - Reversible ribbon feeding mechanism for typewriting machines - Google Patents

Reversible ribbon feeding mechanism for typewriting machines Download PDF

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Publication number
US2616547A
US2616547A US756174A US75617447A US2616547A US 2616547 A US2616547 A US 2616547A US 756174 A US756174 A US 756174A US 75617447 A US75617447 A US 75617447A US 2616547 A US2616547 A US 2616547A
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United States
Prior art keywords
ribbon
lever
spool
power
lug
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US756174A
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English (en)
Inventor
Ronald D Dodge
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Business Machines Corp
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International Business Machines Corp
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Filing date
Publication date
Priority to BE483327D priority Critical patent/BE483327A/xx
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Priority to US756174A priority patent/US2616547A/en
Priority to FR967739D priority patent/FR967739A/fr
Application granted granted Critical
Publication of US2616547A publication Critical patent/US2616547A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J35/00—Other apparatus or arrangements associated with, or incorporated in, ink-ribbon mechanisms
    • B41J35/04—Ink-ribbon guides
    • B41J35/10—Vibrator mechanisms; Driving gear therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J33/00—Apparatus or arrangements for feeding ink ribbons or like character-size impression-transfer material
    • B41J33/14—Ribbon-feed devices or mechanisms
    • B41J33/40—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction
    • B41J33/44—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction automatically
    • B41J33/51—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction automatically and characterised by the use of particular reversing control means
    • B41J33/516—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction automatically and characterised by the use of particular reversing control means using a reversing-feeler responsive to the tension of the ribbon

Definitions

  • the principal object of the present invention is to provide an improved ribbon mechanism.
  • Anobject is to provide a ribbon mechanism which is operated by a source of power other than. thetype bars or the type bar operating trains.
  • An object is to provide a ribbon mechanism which is suitable for use in power operated typewriters.
  • An object is to provide .a ribbon mechanism whichis more positive and reliable in its action.
  • Fig. l is a verticle section of a power operated typewriter and shows the ribbon vibrator mechanisrn.
  • Fig. 2 is a vertical elevation showing the power meansfor actuatingthe ribbon mechanism and theribbon feeding mechanism associated with the left hand ribbon spool.
  • Fig.3 is va detail view showing the ribbon feeding mechanism of Fig. Zin reversed condition.
  • Fig. 4 is a large scale view of the ribbon vibrator mechanism appearing in Fig. 1 and shows the mechanism in position to effect printing through the lower zone of the ribbon.
  • Fig. 5 1s aplan view of the mechanism shown inFig. 4'.
  • Fig. dis a view showing the ribbon vibrator mechanism adjusted to print through the middle zoneof the ribbon.
  • Fig.7 is a viewshowing the ribbon vibrator mechan smadiusted to print through the upper zoneof theribbon.
  • Fig.10 is a planfviewof the means for pivotally supportingthe left ,hand ribbon spool.
  • Fig.1 thereiis shown a vertical section of a power. operated typewriter.
  • the character keys iil are pivoted;.0n .a cross rod H and guided at their front enri s by.a suitable key comb !2, the keysbeingrestored by springs is.
  • the keys Iii controL power mechanism which. includes the power roller l4 normally rotatingin the direction of the arrow when the machine is in use.
  • Eachkegqcontrols itsownpower unit all of which coact with the power roller M to operate the corv fulcrum bar H longitudinally adjustably mounted in the support bar i8.
  • the support bar 18 1s slotted at 58a to receive both the sub-levers i6- and the rounded ends of the associated fulcrum bars ii.
  • the sub-levers iii are held in engagement with their fulcrum bars H by means of springs 19 which are anchored to suitable lugs formed in the fulcrum bars ll.
  • Theupper end of each sub-lever i6 is connected by link 20 to an arm lea formed in the associated type bar l5.- Only one type bar l5 and one sub-lever IS with its associated parts are shown in Fig. 1 but it will be understood that there is a set of these parts for each character key it in the machine.
  • the type bars i5 are pivotally mounted by means of a curved pivot wire 25 (Fig. 1) in the usual segment 22 attached to and forming part of the usual type basket (not shown).
  • This type basket may be case shiitable for the purpose of printing upper case characters or, if desired, the platen 23 may be shiftable for the same purpose.
  • the segment 22 may be provided with the usual type guide 24 and the ribbon Vibrator 25 which isvertically guided on the type guide 2 and normally occupies the position of Fig. 1 in which it is below the printing line.
  • the ribbon vibrator is actuated and controlled by novel means hereinafter. to be described.
  • Each power unit besides the sub-lever it, includes an L-shaped cam 26 pivoted at [6b on the sub-lever i6 and urged in a counterclockwise direction by a spring 21 anchored to an ear formed in the cam 26 and an ear formed in the sublever [6.
  • the sub-lever I6 is formed with an extension on which is pivotally slidably mounted at ltd an interposer 28 having the offset lug or shoe 28a engaging the cam 26 and a similar lug 28b engaging an extension ma formed in the key NJ.
  • the interposer 28 is urged in a clockwise direction by a sprin 29 which is anchored to an ear formed in the interposer 28 and to a stop lug We formed in the extension [60, and the spring also holds the interposer 28 in its left hand position (Fig. 1) with the pivot id at the right hand end of the slot by means of izglgch said interposer is mounted on the pivot
  • a sprin 29 which is anchored to an ear formed in the interposer 28 and to a stop lug We formed in the extension [60, and the spring also holds the interposer 28 in its left hand position (Fig. 1) with the pivot id at the right hand end of the slot by means of izglgch said interposer is mounted on the pivot
  • the depression of the key l0 rocks the interclockwise direction, thereby causing the serrated tread portion 26a of the cam to engage the power roller i4 and be gripped thereby.
  • the power roller then rotates the cam 26 and, due to the eccentricity of the cam tread with respect to the pivot lob, the sub-lever IE will be rocked in a clockwise direction against the tension of spring l9 and thereby actuate the type bar to printing position.
  • a nose portion 18f formed in the cam 26 engages an adjustable spring prong 30a formed in the spring comb 30 and is arrested.
  • the power unit does not propel the type bar the full distance to the printing point with the power unit coupled to the driver throughout the whole cycle, but the adjustment of the spring prong 30a is such that the nose piece lfic will strike said prong before the type bar reaches the printing point and the remainder of the stroke of the type bar will be effected by virtue of the inertia of the power unit and the type bar.
  • the point at which this takes place is determined by adjusting the spring prong 30a up or down by means of an adjusting screw 3
  • the spring prongs 30a are formed as part of a comb spring 30 secured to the support bar [8. This spring comb 30 also is slotted to space apart and guide the adjustable fulcrum bars l1.
  • the interposer 28 is carried in a clockwise direction. If the key i0 should be held depressed, the left hand end of the lug 28b on the interposer will engage the right side of the extension I01; and the parts will stay in this position as long as the key is held depressed, thereby preventing the power unit from repeating. A slight clearance is provided between the extension Ma and the lug 28b in the normal position of the parts so that, when the key If) is released, the spring 29 will snap the interposer 28 back to the position of Fig. 1, permitting another release of the power unit by depression of the key I 0.
  • the ribbon mechanism and the ribbon vibrator are actuated by universal bars which are either driven directly by the power units or are actuated by the keys or certain parts of the trains of connections from the type bars to the keys.
  • the ribbon mechanism is actuated by a separate power unit which is merely rendered effective by the operation of the type bar power units l6 through a universal bar actuated by the power units.
  • a cross-shaft 32 Pivotally mounted on the framework of the machine (Figs. 1 and 2) is a cross-shaft 32 on which is pivotally mounted a universal bar 33 in the form of a vane.
  • This universal 'bar is engaged by nose pieces 169 formed in the sublevers l6 whereby, each time a power unit I6 is operated, the universal bar 33 will be actuated in a counterclockwise direction (Figs. 1 and 2) against the tension of a restoring spring 33a. anchored to the universal bar 33.
  • This movement of the universal bar 33 is utilized to trip a power unit generally designated 34 in Fig. 2.
  • This power unit 34 includes a suitable frame pivoted at 3501. (Fig. 2) to a fixed frame piece 35 suitably supported in the machine framework.
  • An elliptical cam 34a is pivoted at 34b in the frame of the cam unit 34 and cam 34a is provided with two pins 340 located on diametrically opposite sides of the pivot 34b and normally one or the other of the pins is engaged by an arm 34d pivoted at 34c in the frame of the power unit 34.
  • This arm 34d is urged in a clockwise direction by a torsion spring 34 partly coiled around the pivot 34c and hooked to lugs formed in the arm 34d and in the frame of the power unit 34, respectively.
  • a trip lever 34g having an off-set lug 34h coacting with one of two lugs 342' formed in the cam 34a on diametrically opposite sides of the pivot 34b.
  • the spring actuated lever 34d pressing on one of the pins 340,
  • the universal bar 33 is connected by a link 36 (Fig. 2) to the trip lever 34g whereby a counterclockwise motion imparted to the universal bar 33 by the power units l 6 will actuate the trip lever 349 in a clockwise direction and disengage the lug 34h from the lug 342'.
  • a lug 34 formed in the trip lever 34g is positioned in the path of movement of the second lug 341'.
  • the shaft 32 is provided at its ends with the arms 3211, one of which is connected by a link 31 to a lug formed in the frame of the power unit 34.
  • the power unit 34 is restored by a spring 35b (Fig. 2) anchored to the frame of the power unit and to a lug carried by frame 35. This restoring movement is limited by a resilient bumper 350 on which the frame of the cam unit rests and which is carried by frame 35.
  • each of the arms 32a Attached to each of the arms 32a is a link 38, one for each ribbon spool, and these lin s actuate two separate ribbon feeding mechanisms, each associated with a ribbon spool.
  • the drawings show the ribbon feeding mechanism located on the left hand side of the machine but it will be understood that the two mechanisms are similar in construction and. a description of one will sufiice for both.
  • the side plates 39 of the main framework are formed with a large open cut-out portion 39a (Fig. l) to accommodate the ribbon spools of which the left hand spool is designated 40 in Figs. 2 and 3.
  • the ribbon feeding and reversing mechanism for each spool is mounted as a unit in the cut-out 39a of the associated side frame 39 by means of a plate 4
  • (Figs. 2, 3, and 10) is a shouldered stud lla which serves as one pivot acre-seer for the; rib n pool 4.0,,theot-b r pirot 'coneis ina of. a stud; 42a. formedin; the. end ofla: finger button;
  • b formed inthe. plate: 4
  • ) is:c.on nected. to onearmg of a lever 45 (Figs. 2 and 3). pivoted on a stud 46 carried by the plate-.4
  • Means. are provided. for causing the pawls 41 to engage the teeth; 40a ofthe ribbon spools in alternation so as to cause one. ribbon spool to feed untilthe other is, exhausted and then render the other spool. effective to feed and. this mechanism is controlled by the tensionjproducedin the ribbon when the free running spool is exhausted.
  • is a lever50'to which is pivoted at 5
  • . is an interposer 52- which is connectedby a spring'link'53i to one arm of a tension lever 54 pivoted at MototheplateM.
  • the tension lever 54 is" formed with a ribbon guide lug 54a having anopenribbon guiding slotv 54?) (Fig. 10) formed therein andisurgediin a'.clock-. wise direction against: a stop lug. 4
  • the left handspool 40 is shown inLfree running condition in Fig. 3, that is, withthe ribbon R unwinding from. the spool and pawl 41' retracted. Due to the fact that the ribbon. is secured'to the spool, there will come a time when the ribbon will beno longer capable ofunwinding' from the spool 45 and this will anchor the ribbon. and, due to-the tendency of. the. ribbonto straighten, will rock the tension control lever 54 in a counterclockwisedirection (Fig. 3);. Due to thelink con' nection 53 interposer.- 54 willberocked clockwise into the path of an off-set lug- 45b formed in the lever 45. Consequently" thenext. oscillation of the lever 45 will cause. the; plate 5
  • Fig. 2 which illustrates the. left hand spool. feeding mechanism in .a driving condition.
  • a pawl 56 constructed somewhat similarly to the pawl 41 and similarly engaged by the. lug 5
  • the pawl 56 is urged in a. counterclockwise direction by a spring 51 ans chored to a lug formedin the plate 5] and alug formed in. the pawl.
  • the pawl 56 ispivotallymounted. on a fixed dog 58 secured. tov the plate 4
  • for the, left hand spool 40 has a loose pinconnection 68a (Figs. 2, 3,. and 9). with an arm. carried by a cross-shaft 6
  • for the right hand spool (not shown) is similarly connected at 620. to an arm 62 disposed on the opposite end of the shaft 5i adjacent the plate 4
  • the levers 55 are formed with. finger pieces 55a which may be grasped by the operator and pressed up or down, as desired.
  • the arm 62 In order to hold the plates 5
  • the toggle spring 63 is fairly stiff with the result that the actuating" lever 45 and the interposer 52 of either spool 49 need only raise the associated plate M a little beyond the dead center position of the toggle'spring: 53 which thereafter becomes effective to snap the plate 5! to the. alternate position.
  • One of'the advantages of the ribbon mechanism described above is it imposes a very small but constant load on the type bar operating mechanism, particularly at the times when the ribbon In ordinary ribbon mechanisms the full power necessary to effect the reversal of the. ribbon feedin mechanism imposes an additional load on the type bar mechanism,.. causing the type bar to print lighter while the ribbon is reversing than at other times, and
  • the tread portion Ma of the power roller which actuates the cam unit 34 is somewhat larger in diameter than the main part of the power roller in order to cause the ribbon mechanism to be actuated at a somewhat faster rate than the type bar in order to insure that the ribbon will be fully fed before the next type bar reaches printing position, and also to insure that the ribbon will be reversed immediately so as to minimize striking characters in succession through the same spot on the ribbon.
  • the ribbon vibrator 25 (Fig. 1) is actuated by mechanism shown in the lower left hand corner thereof and illustrated in successive manually set positions in Figs. 4 to 8.
  • a frame 65 which extends vertically and has an offset lug 65a on which is pivoted the lever 66. the free end of which is connected by a link 61 to the ribbon vibrator 25.
  • Pivoted to the lever 65 is a link 68 which, with a similar link 69, forms a toggle and the common pivot of the toggle link 68, 69 is connected by a shift link 70 to a shift lever H pivoted at 65b to the frame 65.
  • the lower arm of the lever H is connected by a link E2 to the universal bar 33 near its midpoint.
  • the link l2 Since the universal bar 33 is actuated clockwise each time a character is printed, the link l2 will be thrust to the left in Figs. 4 to 8, thereby rocking the lever H clockwise and drawing the link 70 to the right. This tends to straighten the toggle 68, 69 and thereby rock the lever 66 counterclockwise to elevate the link 67 and the ribbon vibrator 25.
  • the height to which the ribbon vibrator 25 is elevated depends upon the position of the pivot for the lower end of the toggle link 69.
  • the link 69 is pivoted at 13a to a control lever 13 secured to a shaft 14 journaled in the plate 65.
  • the shaft 14 extends toward the left hand side plate 39 (Fig.
  • the ribbon vibrator 25 Besides the normal retracted position of the ribbon vibrator 25 in which the ribbon R is located the ribbon, namely, a zone along the upper edge of the ribbon, a middle zone, and a zone along the lower edge, in order that the ribbon may be uniformly exhausted.
  • Fig. 4 illustrates the position of the mechanism whenthe ribbon vibrator is elevated to next-tominimumheight to effect striking of the type through the upper zone adjacent the upper edge of the ribbon.
  • the lever 70 is held in its various positions by means of a detent lever 19 which is pivoted at 650 in the frame and is urged in a clockwise direction by a spring 8! anchored to a lug formed in the lever 19 and to a lug formed in an extension arm 53b of the lever 13.
  • the detent arm 19 is provided with a roller 19a which may engage either of two notches 13c, 13d to hold the lever 13 in the positions of Fig. 4 and Fig. 6, respectively.
  • the lever 13 is provided with the bentover stop lugs 73:: and.
  • the frame 65 is formed with an extension arm 650 to which is attached aresilient bumper 65d which may be made of rubber or a resilient synthetic plastic of suitable characteristics.
  • a ribbon feeding mechanism for power operated typewriters and like machines having a main power actuator and power units for operating the type bars comprising a universal bar actuated each time one of said power units is operative, a ribbon feeding mechanism, and a power unit actuated by said main power actuator and rendered effective-by said universal bar for actuating said ribbon feeding mechanism.
  • typing means including a series of type bars and an inking ribbon therefor, a series of character keys for controlling the typing means, a main power actuator, power units for operating the type bars and selectively engaged with ,the main power actuator by selec tive operation of said keys; mechanism for feeding said ribbon'including a pair of ribbon spools and a pair of oscillatable members, one for each ribbon spool, for feeding said spools, and including shiftable disabling means associated with each spool forflrendering the feeding mechanism operative and inoperative, said disabling means being interconnected whereby disabling the feeding mechanism with respect to either spool renders the feeding mechanism effective with respect to the other; means responsive to exhaustion of the ribbon from said spools; a pair of coupling devices, one for each spool and operated by the exhaustion responsive means for coupling the oscillatable members to the shiftable disabling means, said coupling devices being rendered effective to shift the disabling means to disable the feeding mechanism with

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  • Impression-Transfer Materials And Handling Thereof (AREA)
US756174A 1947-06-21 1947-06-21 Reversible ribbon feeding mechanism for typewriting machines Expired - Lifetime US2616547A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BE483327D BE483327A (nl) 1947-06-21
US756174A US2616547A (en) 1947-06-21 1947-06-21 Reversible ribbon feeding mechanism for typewriting machines
FR967739D FR967739A (fr) 1947-06-21 1948-06-15 Mécanisme d'avance du ruban pour machines à écrire

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US673064XA 1947-06-21 1947-06-21
US967739XA 1947-06-21 1947-06-21
US278003XA 1947-06-21 1947-06-21
US756174A US2616547A (en) 1947-06-21 1947-06-21 Reversible ribbon feeding mechanism for typewriting machines

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US2616547A true US2616547A (en) 1952-11-04

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US756174A Expired - Lifetime US2616547A (en) 1947-06-21 1947-06-21 Reversible ribbon feeding mechanism for typewriting machines

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BE (1) BE483327A (nl)
FR (1) FR967739A (nl)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3038582A (en) * 1960-12-23 1962-06-12 Royal Mcbee Corp Ribbon feed mechanism for business machines and the like
US3048254A (en) * 1959-05-01 1962-08-07 Sperry Rand Corp Ribbon mechanism for typewriter
US3194379A (en) * 1963-04-05 1965-07-13 Royal Mcbee Corp Ribbon feed mechanism

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US936257A (en) * 1908-08-21 1909-10-05 Oscar Rutishauser Device for automatically reversing the travel of type-writer ribbons.
US1089042A (en) * 1913-11-21 1914-03-03 Ellis Adding Typewriter Company Ribbon winding and reversing mechanism.
US1196622A (en) * 1914-05-06 1916-08-29 Int Money Machine Co Ribbon-feeding mechanism.
US1602757A (en) * 1924-09-26 1926-10-12 North East Appliances Inc Power mechanism
US1680135A (en) * 1924-09-18 1928-08-07 Underwood Elliott Fisher Co Typewriting machine
US1722937A (en) * 1927-12-23 1929-07-30 Royal Typewriter Co Inc Typewriting machine
US1800854A (en) * 1927-04-06 1931-04-14 Barr Morse Corp Typewriter and the like
US1820903A (en) * 1930-04-29 1931-09-01 L C Smith & Corona Typewriters Typewriting machine
US1922991A (en) * 1930-09-11 1933-08-15 Electromatic Typewriters Inc Typewriting machine
US2152848A (en) * 1936-07-17 1939-04-04 Underwood Elliott Fisher Co Typewriting machine

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US936257A (en) * 1908-08-21 1909-10-05 Oscar Rutishauser Device for automatically reversing the travel of type-writer ribbons.
US1089042A (en) * 1913-11-21 1914-03-03 Ellis Adding Typewriter Company Ribbon winding and reversing mechanism.
US1196622A (en) * 1914-05-06 1916-08-29 Int Money Machine Co Ribbon-feeding mechanism.
US1680135A (en) * 1924-09-18 1928-08-07 Underwood Elliott Fisher Co Typewriting machine
US1602757A (en) * 1924-09-26 1926-10-12 North East Appliances Inc Power mechanism
US1800854A (en) * 1927-04-06 1931-04-14 Barr Morse Corp Typewriter and the like
US1722937A (en) * 1927-12-23 1929-07-30 Royal Typewriter Co Inc Typewriting machine
US1820903A (en) * 1930-04-29 1931-09-01 L C Smith & Corona Typewriters Typewriting machine
US1922991A (en) * 1930-09-11 1933-08-15 Electromatic Typewriters Inc Typewriting machine
US2152848A (en) * 1936-07-17 1939-04-04 Underwood Elliott Fisher Co Typewriting machine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3048254A (en) * 1959-05-01 1962-08-07 Sperry Rand Corp Ribbon mechanism for typewriter
US3038582A (en) * 1960-12-23 1962-06-12 Royal Mcbee Corp Ribbon feed mechanism for business machines and the like
US3194379A (en) * 1963-04-05 1965-07-13 Royal Mcbee Corp Ribbon feed mechanism

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Publication number Publication date
BE483327A (nl)
FR967739A (fr) 1950-11-10

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