US2078224A - Copy printing mechanism - Google Patents

Copy printing mechanism Download PDF

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US2078224A
US2078224A US631641A US63164132A US2078224A US 2078224 A US2078224 A US 2078224A US 631641 A US631641 A US 631641A US 63164132 A US63164132 A US 63164132A US 2078224 A US2078224 A US 2078224A
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ribbon
shaft
spools
opposite ends
copy
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US631641A
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Harry D Atwood
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J C TRIMBY
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J C TRIMBY
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J35/00Other apparatus or arrangements associated with, or incorporated in, ink-ribbon mechanisms
    • B41J35/30Manifolding or like arrangements

Definitions

  • This invention relates to copy-printing attachments for typewriters and similar machines and more particularly to the printing of copies by an auxiliary inking ribbon lying alongside the main printing ribbon.
  • the general object of the present invention is to provide a new and improved copy-printing attachment of the above character which is simple and inexpensive in construction, convenient and reliable in operation, and readily adaptable to standard typewriter constructions.
  • Another object is to provide a novel mechanism for supporting the copy-printing ribbon and maintaining the same in proper relation to the main ribbon while at the same time permitting movement thereof into and out of active position.
  • a further object is to provide a novel means for effecting feed of the copy-printing ribbon automatically and also reversal of such feed.
  • the invention also resides in the novel and compact arrangement of the parts permitting the use of a second copy ribbon for printing fourth and fifth copies.
  • FIG. 1 is a perspective view of a copy-printing attachment embodying the features of the present invention.
  • Fig. 2 is an end elevational view.
  • Fig. 3 is a section taken along the line 33 of Fig. 2.
  • Fig. 4 is a section taken along the line 4-4 of Fig. 3.
  • Fig. 5 is a. perspective view of the parts of the mechanism for effecting reversal of the ribbon feed.
  • Fig. 6 is a fragmentary perspective view of the line-spacing lever of a typewriter and the parts of the copy-printing attachment actuated thereby.
  • the numeral 1 represents the side frames of the carriage frame on a standard typewriter having a rotatably supported platen 8 opposite which the main ribbon 9 is led through guides Ill. Stepby-step rotation of the platen to effect line-spacing and lateral shifting of the carriage are effected by well known ratchet mechanism (not shown) actuated by the usual hand lever pivoted at I2 on the carriage.
  • the auxiliary ribbon by which second and third copies may be printed comprises an inked Strip I3 having opposite ends wound on spools l4 and the intermediate portion led through inclined slots ii in depending arms l8 and thus adapted for movement in a vertical plane into and out of printing position behind the main ribbon 9.
  • the arms l6 are' attached to blocks 22, bolted to intermediate blocks ll providing journals for opposite ends of a tubular shaft l8 upon which the spools l4 areloosely mounted between the blocks.
  • the latter are dis- 0 posed in vertical guide slots IS in parallel plates 20 having flanges 2
  • Plates 15 22 secured to the blocks I! on opposite sides of the plates 20 serve to maintain the ribbon-supporting arms IS in properly spaced relation.
  • a shaft 20 23 Extending through the tube l8 with ends projecting beyond the ends of the latter is a shaft 20 23 having pinions 24 fast. on its opposite ends and meshing with the teeth of two vertical bars 25 secured at their lower ends to the flanges 2
  • the shaft 23 thus supports the spools l4 and by vir- 25 tue of the constant engagement of the pinions 24 with the stationary rack bars, the shaft is always maintained in exactly horizontal position while at the same time being adapted for bodily movement in a vertical plane to carry the ribbon I3 30 into and out of the active position shown in Fig. 3.
  • this means comprises a pair of clutches 35 and 36 having a single control element in the form of atube 37 enclosing the shaft 88 and adapted to be shifted axially between two positions in either of which the tube is maintained by a spring detent 38 housed within a knurled sleeve 39 by which the tube is grasped during shifting.
  • Each of the clutches comprises a hub 6t fast on the end of the tube 37 and having teeth ll projecting axially beyond lugs 62 on the shaft i8 and having inner ends adapted to enter apertures 43 in the hub portion of the adjacent spool.
  • the clutch 3t willbe engaged and the clutch 35 disengaged with the result that rotationof the shaft 98 will advance the ribbon l3 to the right unwinding the same from the left-hand spool and winding the ribbon onto the right-hand spool.
  • the clutch Upon shifting the tube 31 into its other'positio'n, the clutch will be engaged thereby adapting the feed mechanism foradvance of the ribbon i3 in the reverse direction.
  • do not enter the holes 43 properly upon shifting of the 35 tube 31, such entry will be permitted upon twisting the tube slightly as permitted by the relatively wide spacing of the teeth H.
  • friction brakes may be employed each comprising a drum 44 fast on the shaft l8 adjacent each spool and 4.5 a resilient band 45 encircling the drum with its opposite ends anchored to a pin 46 on the spool.
  • the degree of braking action may be adjusted by the screw 41.
  • a pawl 48 (Fig. 2) is pivoted at 49 on the plate 22 and urged toward the teeth 32 by a spring 5
  • the copy-printing attachment above described is adapted for printing two copies of the original, one on a paper sheet placed behind the ribbon l3 and the other on a transparent sheet disposed between the ribbons 9 around rollers 54 and through guide slots 55 in depending arms 56.
  • the latter and the spools 53 are mounted for vertical movement on the 5 plates 20 in the same manner as the arms a d spools for the ribbon IS.
  • the spools are maintained in horizontal position in the same way as the first mentioned spools, the rack-bars 5i engaging the pinions on the spool supporting shaft having teeth facing in the opposite direc- 5 tion from the teeth on the bars 25. This enables the spools it and 58to be placed close together thereby contributing to the overall compactness of the attachment as a whole.
  • the 10 supporting means therefor is lowered by grasping the sleeve 58 thereby bringing the intermediate portion of the ribbon alongside the ribbon it as shown in Fig.2.
  • a ratchet wheel 59 for advancing the ribbon 52 i5 is brought into engagement with a pawl 6t so that the ribbon will be advanced inthe same manner as the ribbon I3. If only three copies are to be printed, the ribbon 52 is raised to inactive position as shown in Fig. l. 20
  • the attachment provided is readily adaptable to -standard typewriter constructions and is rendered exceedingly compact and simple in construction by virtue of the novel manner of guid- 25 ing the ribbon spool supporting means and the relation of the guides for the different ribbons.
  • manipulation of the attachment for reversing the direction of ribbon feed is rendered simple'and convenient by employing -a single 30 clutch control element.
  • means for supporting a copy-printing ribbon for vertical movement intoand out of active position comprising a horizontal tubular shaft, a pair of spools loosely mounted on opposite ends of said shaft and hav- 7o ing opposite ends of said ribbon wound thereon, means by which one or the other of said spools may be coupled to said shaft, a pair of stationary upright rack-bars at opposite ends of said shaft, and a shaft extending through said tubular shaft and having pinions fast on its opposite ends and meshing with said rack-bars whereby to maintain said tubular shaft in horizontal position during vertical movement thereof.
  • means for supporting a copy-printing ribbon for vertical movement into and out of active position comprising a pair of concentric shafts one rotatable within the other, a pair of spools loose on opposite ends of one of said shafts and having opposite ends of said ribbon wound thereon, means by which one or the'other of said spools may be coupled to the latter shaft, means for turning the latter to advance the intermediate portion of the ribbon ion- 5 gitudinally of the shaft, a pair of stationary upright rack-bars. and pinions on opposite ends of said other shaft meshing with the respective rack-bars.
  • means for supporting a copy-printing ribbon for vertical movement into and out of active position comprising a pair of horizontal concentric shafts guided for bodily vertical movement, a pair of spools on opposite ends of one of said shafts having opposite ends of said ribbon wound thereon and adapted to be coupled selectively to the latter shaft, and means operatively associated with opposite ends of the other shaft to maintain the shafts in horizontal position during vertical movement thereof.
  • a horizontal shaft mounted on the typewriter carriage for vertical movement, a pair-0f spools loose on opposite ends of said shaft, a copy-ribbon having opposite ends wound on said spools, a frame movas able with said shaft and providingguides leading the intermediate portion of the ribbon in a straight path parallel to the typewriter platen.
  • means for supporting a copy printing ribbon for vertical movement into and out of active position comprising a pair of horizontal shafts mounted to turn about a common axis and arranged for bodily vertical movement, a pair of spools at opposite ends of one of said shafts having opposite ends of said ribbon wound thereon and adapted to be driven by the latter shaft, and means operatively associated with opposite ends of the other shafts to maintain the shafts in horizontal position during vertical movement thereof to carry said ribbon into and out of printing position.

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Description

A ril27, 1937. H. D. ATWOOD V 2, 8,
COPY PRINTING MECHANISM N Filed Sept. 5, 1932 2 Shets-Sheet 1 April 27, 1937. H. D. ATWOOD COPY PRINTING MECHANISM Filed Sept. 3, 1932' 2 SheetsSheet 2 47 43 J9 J6 63 4 /2 a; J8
.24 w V T 2 17 i 14 45 I 31/ i i i 21 I i5 1 x 4 F m J4 S Z7 15 p l'ruzenl'am A Mf D 04%000 Patented. Apr. 27, 1937 com? rmm'nva rrccmmsu Barry D. Atwood, Detroit, Mich, aasignor of 'one-half to J. C. Trlmby, Detroit, Mich.
Application September 3, 1932, Serial No. 631,641
8 Claims.
- This invention relates to copy-printing attachments for typewriters and similar machines and more particularly to the printing of copies by an auxiliary inking ribbon lying alongside the main printing ribbon.
The general object of the present invention is to provide a new and improved copy-printing attachment of the above character which is simple and inexpensive in construction, convenient and reliable in operation, and readily adaptable to standard typewriter constructions.
Another object is to provide a novel mechanism for supporting the copy-printing ribbon and maintaining the same in proper relation to the main ribbon while at the same time permitting movement thereof into and out of active position.
A further object is to provide a novel means for effecting feed of the copy-printing ribbon automatically and also reversal of such feed.
The invention also resides in the novel and compact arrangement of the parts permitting the use of a second copy ribbon for printing fourth and fifth copies.
Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings in which Figure 1 is a perspective view of a copy-printing attachment embodying the features of the present invention.
Fig. 2 is an end elevational view.
Fig. 3 is a section taken along the line 33 of Fig. 2.
Fig. 4 is a section taken along the line 4-4 of Fig. 3.
Fig. 5 is a. perspective view of the parts of the mechanism for effecting reversal of the ribbon feed.
Fig. 6 is a fragmentary perspective view of the line-spacing lever of a typewriter and the parts of the copy-printing attachment actuated thereby.
In the exemplary form shown in the drawings, the numeral 1 represents the side frames of the carriage frame on a standard typewriter having a rotatably supported platen 8 opposite which the main ribbon 9 is led through guides Ill. Stepby-step rotation of the platen to effect line-spacing and lateral shifting of the carriage are effected by well known ratchet mechanism (not shown) actuated by the usual hand lever pivoted at I2 on the carriage.
The auxiliary ribbon by which second and third copies may be printed comprises an inked Strip I3 having opposite ends wound on spools l4 and the intermediate portion led through inclined slots ii in depending arms l8 and thus adapted for movement in a vertical plane into and out of printing position behind the main ribbon 9. At 5 their upper ends, the arms l6 are' attached to blocks 22, bolted to intermediate blocks ll providing journals for opposite ends of a tubular shaft l8 upon which the spools l4 areloosely mounted between the blocks. The latter are dis- 0 posed in vertical guide slots IS in parallel plates 20 having flanges 2| at their lower ends bolted -or otherwise suitably secured to the carriage frame plates 1 and connected at their rear ends by a bar 2 I along the upper sides thereof. Plates 15 22 secured to the blocks I! on opposite sides of the plates 20 serve to maintain the ribbon-supporting arms IS in properly spaced relation.
Extending through the tube l8 with ends projecting beyond the ends of the latter is a shaft 20 23 having pinions 24 fast. on its opposite ends and meshing with the teeth of two vertical bars 25 secured at their lower ends to the flanges 2| and at their upper ends to the plates 20. The shaft 23 thus supports the spools l4 and by vir- 25 tue of the constant engagement of the pinions 24 with the stationary rack bars, the shaft is always maintained in exactly horizontal position while at the same time being adapted for bodily movement in a vertical plane to carry the ribbon I3 30 into and out of the active position shown in Fig. 3.
Automatic advance of the ribbon l3 as an incident to normal operation of the typewriter is effected through the medium of a slide bar 28 supported on the left hand flange 2| and be- 35 tween the plate 20 and the rack bar 25 and having a lateral arm 21 (Fig. 6) rigid therewith and depending therefrom into a position to be engaged by the usual arm 28 on the line-space lever Pivoted on the slide and nonnallyurged 40 upwardly by a spring 29 into a position determined by a stop pin 30 is a pawl 3| adapted, when the ribbon I3 is lowered to active position, to be brought into engagement with teeth 32 on the periphery of a ratchet wheel 33 fast upon 45 the end of the tubular shaft l8. As the slide 28 -is moved rearwardly upon actuation of the linespace lever I l, the pawl 3| catches behind one of the teeth 32 and advances the shaft l8. Upon release of the lever II a spring 34 acting on the 50 usual line-spacing slide 34' returns the slide 26 to its initial position. Thus in normal operation of the typewriter with the ribbon l3 lowered to active position, a step-by-step movement will be imparted to the shaft. when the ribbon and its supporting parts are raised to inactive position as shown in Fig. 1, the ratchet wheel is withdrawn from operative association with the pay, that the shaft l8 will not be advanced in he subsequent operation of the typewriter.
Means is provided for coupling one or the other of the spools it to the shaft is and thereby cause the ribbon it to be advanced in one 10 direction or the other. In the present instance, this means comprises a pair of clutches 35 and 36 having a single control element in the form of atube 37 enclosing the shaft 88 and adapted to be shifted axially between two positions in either of which the tube is maintained by a spring detent 38 housed within a knurled sleeve 39 by which the tube is grasped during shifting. Each of the clutches comprises a hub 6t fast on the end of the tube 37 and having teeth ll projecting axially beyond lugs 62 on the shaft i8 and having inner ends adapted to enter apertures 43 in the hub portion of the adjacent spool. When the tube Si is shifted to the right as shown in Fig. 3, the clutch 3t willbe engaged and the clutch 35 disengaged with the result that rotationof the shaft 98 will advance the ribbon l3 to the right unwinding the same from the left-hand spool and winding the ribbon onto the right-hand spool. Upon shifting the tube 31 into its other'positio'n, the clutch will be engaged thereby adapting the feed mechanism foradvance of the ribbon i3 in the reverse direction. In the event that the teeth 6| do not enter the holes 43 properly upon shifting of the 35 tube 31, such entry will be permitted upon twisting the tube slightly as permitted by the relatively wide spacing of the teeth H.
To avoid slackness in the ribbon by overrunning of the spool from which the ribbon is being unwound, provision is made for the application of frictional forces constantly resisting rotation of the spools i4. For this purpose, friction brakes may be employed each comprising a drum 44 fast on the shaft l8 adjacent each spool and 4.5 a resilient band 45 encircling the drum with its opposite ends anchored to a pin 46 on the spool. The degree of braking action may be adjusted by the screw 41.
The spool from which the ribbon'is unwound.
in the active motion of the slide 26 will tend to turn backwardly upon retraction of the slide which turning would, if permitted, produce considerable slack in the ribbon permitting the ribbon to move laterally relative to the paper causing smearing thereof. To avoid this, a pawl 48 (Fig. 2) is pivoted at 49 on the plate 22 and urged toward the teeth 32 by a spring 5| and the teeth 32 are spaced so close together that the pawl will be disposed close to one of the shoulders on the teeth so as to prevent any substantial reverse movement of the ratchet wheel as the movement of the slide 26 reverses.
The copy-printing attachment above described is adapted for printing two copies of the original, one on a paper sheet placed behind the ribbon l3 and the other on a transparent sheet disposed between the ribbons 9 around rollers 54 and through guide slots 55 in depending arms 56. The latter and the spools 53 are mounted for vertical movement on the 5 plates 20 in the same manner as the arms a d spools for the ribbon IS. The spools are maintained in horizontal position in the same way as the first mentioned spools, the rack-bars 5i engaging the pinions on the spool supporting shaft having teeth facing in the opposite direc- 5 tion from the teeth on the bars 25. This enables the spools it and 58to be placed close together thereby contributing to the overall compactness of the attachment as a whole.
When it is desired to use the ribbon 52, the 10 supporting means therefor is lowered by grasping the sleeve 58 thereby bringing the intermediate portion of the ribbon alongside the ribbon it as shown in Fig.2. In such movement a ratchet wheel 59 for advancing the ribbon 52 i5 is brought into engagement with a pawl 6t so that the ribbon will be advanced inthe same manner as the ribbon I3. If only three copies are to be printed, the ribbon 52 is raised to inactive position as shown in Fig. l. 20
From the foregoing it will be apparent that the attachment provided is readily adaptable to -standard typewriter constructions and is rendered exceedingly compact and simple in construction by virtue of the novel manner of guid- 25 ing the ribbon spool supporting means and the relation of the guides for the different ribbons. In addition, manipulation of the attachment for reversing the direction of ribbon feed is rendered simple'and convenient by employing -a single 30 clutch control element.
I claim as my invention:
1. In combination with a typewriter having a laterally shiftable carriage frame with a platen roller thereon, two upright members secured to 35 opposite ends of said frame and each having oppositely facing rack-teeth along their forward and rearward vertical edges, two parallel horizontal shafts adapted for independent vertical movement and having pinions on their opposite 40 ends meshing with said racks whereby to maintain the shafts in horizontal positions, a pair of spools on each of said shafts, two copy ribbons each having opposite ends wound on the spools on one of said shafts and a substantially straight 45 intermediate portion-movable vertically with the shaft, and means for turning said shafts automatically as an incident to normal operation of said typewriter with the shafts lowered to bring the ribbons opposite said platen roller. 50
2. In combination with a typewriter having a laterally shiftable carriage frame with a platen roller thereon, two upright members secured to opposite ends of said frame, a pair of parallel horizontal shafts guided for bodily vertical move- 55 ment by said members, a pair of spools on opposite ends of eachshaft, a pair of copy-printing ribbons each having opposite ends wound on the spools of one pair, ratchet wheels each on the end of one of said shafts, a horizontal slide 60 adapted to be shifted rearwardly by operation of the line-spacing lever of said typewriter, and a pair of pawls mounted on said slide and adapted to engage the respective ratchet wheels upon lowering of said shafts. v 5
3. In a typewriting machine, means for supporting a copy-printing ribbon for vertical movement intoand out of active position comprising a horizontal tubular shaft, a pair of spools loosely mounted on opposite ends of said shaft and hav- 7o ing opposite ends of said ribbon wound thereon, means by which one or the other of said spools may be coupled to said shaft, a pair of stationary upright rack-bars at opposite ends of said shaft, and a shaft extending through said tubular shaft and having pinions fast on its opposite ends and meshing with said rack-bars whereby to maintain said tubular shaft in horizontal position during vertical movement thereof.
4. In a typewriting machine, means for supporting a copy-printing ribbon for vertical movement into and out of active position comprising a pair of concentric shafts one rotatable within the other, a pair of spools loose on opposite ends of one of said shafts and having opposite ends of said ribbon wound thereon, means by which one or the'other of said spools may be coupled to the latter shaft, means for turning the latter to advance the intermediate portion of the ribbon ion- 5 gitudinally of the shaft, a pair of stationary upright rack-bars. and pinions on opposite ends of said other shaft meshing with the respective rack-bars.
5. In a typewriting machine. means for supporting a copy-printing ribbon for vertical movement into and out of active position comprising a pair of horizontal concentric shafts guided for bodily vertical movement, a pair of spools on opposite ends of one of said shafts having opposite ends of said ribbon wound thereon and adapted to be coupled selectively to the latter shaft, and means operatively associated with opposite ends of the other shaft to maintain the shafts in horizontal position during vertical movement thereof.
6. In combination with a typewriter, a horizontal shaft mounted on the typewriter carriage for vertical movement, a pair-0f spools loose on opposite ends of said shaft, a copy-ribbon having opposite ends wound on said spools, a frame movas able with said shaft and providingguides leading the intermediate portion of the ribbon in a straight path parallel to the typewriter platen. means by which one of said spools may be coupied to said shaft while the other is uncoupled 4Q therefrom, means resisting overrunning of the uncoupled spool, a pawl and ratchet mechanism actuated by the line-spacing lever of the typewriter to advance said shaft with a step-by-step motion, and retaining means engaging the ratchet mechanism to limit reverse movement of the shaft after release of the line-space lever, said retaining means and the teeth of the ratchet being arranged-to become effective immediately upon retraction of said lever whereby to prevent the occurrence of slack in the straight portion of said ribbon.
7. In combination with a typewriter having a line-space member arranged for manual oscillation, a horizontal shaft mounted on the typewriter carriage for bodily vertical movement, a pair of spools loose on opposite ends of said shaft, a copy-printing ribbon having opposite ends wound on said spools and its intermediate portion guided in a straight path parallel to the typewriter platen. means by which one of said spools may be coupled to said shaft while the other is uncoupled therefrom, means providing a one-way driving connection between the line-space member and said shaft whereby to advance the shaft upon movement of the member in one direction. and means becoming operative immediately upon the initial retracting movement of said member to hold said shaft against reverse movement whereby to maintain the straight portion of said ribbon taut.
8. In a typewriting machine, means for supporting a copy printing ribbon for vertical movement into and out of active position comprising a pair of horizontal shafts mounted to turn about a common axis and arranged for bodily vertical movement, a pair of spools at opposite ends of one of said shafts having opposite ends of said ribbon wound thereon and adapted to be driven by the latter shaft, and means operatively associated with opposite ends of the other shafts to maintain the shafts in horizontal position during vertical movement thereof to carry said ribbon into and out of printing position.
- HARRY D. ATWOOD.
US631641A 1932-09-03 1932-09-03 Copy printing mechanism Expired - Lifetime US2078224A (en)

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