Method and apparatus for applying ink to ribbons

Disclosed is a method and apparatus for inking ribbons used in printing devices. Ribbon to be inked is unwound under tension from a core and passed over a heated roller and between a pair of transfer rollers. The transfer rollers lie in contact with inking rollers disposed in troughs of ink. The inking rollers have metering rollers in contact with the transfer rollers to meter a predetermined quantity of ink onto the transfer rollers. Once ink is transferred to the ribbon, the ribbon is passed over another heated roller to spread the ink and smooth the ribbon. A take-up roller winds the inked ribbon about a second core. The heated rollers on opposite sides of the transfer rollers engage opposite sides of the ribbon.

The present invention relates to a method and apparatus for applying ink to 
used inked ribbons, such as are employed in printing apparatus and more 
particularly in business machines and computer peripheral equipment. 
In one aspect, the present invention provides a method for applying fresh 
ink to a used inked ribbon comprising the steps of applying heat to the 
ribbon to expand and unwrinkle or smooth the fibers of the ribbon, 
applying ink under pressure to at least one side of the ribbon to 
impregnate the ink into the interstices of the fibers of the ribbon and 
again applying heat to the ribbon to spread the ink and smooth the ribbon. 
Preferably, ink is applied under pressure to both sides of the ribbon. 
Preferably, the ribbon is initially heated on one side by passing it under 
tension over a heated rotating roller thereby to flex and heat the ribbon. 
After the ink is applied, final heating of the ribbon is effected by 
applying heat to the other side of the ribbon by passing it under tension 
over another heated rotating roller to spread the ink and smooth the 
ribbon. 
Advantageously, the inking of the ribbon under pressure is effected by 
passing the ribbon between two ink transfer rollers, each of which 
receives ink from a roller rotating in a trough of ink. 
In another aspect of the present invention, there is provided apparatus for 
applying fresh ink to a used inked ribbon, including a frame, means 
carried by the frame for rotatably carrying a core thereby enabling the 
ribbon to be unwound therefrom, a first roller for applying heat to one 
side of the ribbon and over which the ribbon passes as it is unwound from 
its core, second and third rollers carried by the frame for applying ink 
to opposite sides of the ribbon as it passes between them after being 
heated by the first roller, a fourth roller carried by the frame for 
contacting and applying heat to the side of the ribbon opposite the one 
side thereof, and means for passing the ribbon over the first, second, 
third and fourth rollers and winding the inked ribbon on a second core.

Referring to the drawings, a machine constructed in accordance with the 
present invention includes a frame having two inclined parallel spaced 
side frame members 1 having their upper ends supported by columns 2 which 
rest on a base member 3. The lower ends of the side frame members 1 also 
rest on base member 3. Between side frame members 1 are arranged, in the 
direction of travel of a ribbon to be re-inked, a shaft 4 for supporting a 
core 5 containing a ribbon R to be re-inked, a first heated roller 6, a 
second heated roller 8 and a take-up shaft 9 supporting a core 10 (FIG. 2) 
on which the re-inked ribbon is re-wound. The rollers 6 and 8 contain 
electrical heating elements and electrical power is provided thereto by 
connections 33. 
The ribbon R, to be re-inked and supported on core 5 (FIG. 2), is 
positioned between chucks 11 on shaft 4. Shaft 4 is thus split into two 
parts. Ribbon R passes from core 5 over the first heated roller 6 with its 
lower surface (as viewed in FIG. 1) in contact with roller 6. Ribbon R 
then passes through the re-inking station 7. 
In accordance with the present invention, re-inking station 7 comprises two 
pairs of side frames 7a and 7n. The side frame 7a supports an 
ink-containing trough 7b in which an ink roller 7c rotates in contact with 
a transfer roller 7d. Roller 7d applies ink to the lower side of ribbon R. 
A further ink roller 7a rotates in an ink-containing trough 7f supported 
by side frames 7n. Roller 7e applies ink to the other or upper side of the 
ribbon through a transfer roller 7g. Thus, ribbon R passes under pressure 
through the nip between the two ink transfer rollers 7d and 7g. Ribbon R 
then passes over heated roller 8 supported on shaft 12, and is then 
re-wound on the take-up core 10 held by chunks 13 on shaft 9. Shaft 9 is 
thus split into two parts similarly as shaft 4. Shaft 12 is mounted 
between two parallel swing arms 39. 
More specifically, ink roller 7c rotates in ink trough 7b in contact with a 
metering roller 7h which meters the quantity of ink applied to the 
transfer roller 7d. Roller 7d, in turn, applies ink to the lower side of 
ribbon R. A similar arrangement including a metering roller 7j is provided 
for ink roller 7e. Ink roller 7e contacts the transfer roller 7q which 
applies ink to the upper surface of ribbon R. Ink is fed to the troughs 
through an input 7p from a pump. Ink overflow from the troughs flows 
through a pipe 7m to the ink reservoir which feeds the pump. 
A control for metering the ink is illustrated in FIG. 1. Particularly, 
doctor blades 7r and 7s are arranged adjacent the ends of transfer rollers 
7d and 7g to remove surplus ink from those marginal edge areas of ribbon R 
which have not been subject to de-inking in use and which therefore 
already have a substantial full content of ink. 
As illustrated in FIG. 2, the left-hand part of the shaft 4, which supports 
the core 5 carrying the ribbon R to be re-inked, is axially slidable in a 
bearing block 14. A compression spring 15 is arranged around shaft 4 
between bearing block 14 and a collar 4a secured to the shaft. The 
right-hand part of shaft 4 extends through a bearing block 16 into a 
further section of the machine, generally indicated at 17, and carries two 
spaced collars 4b defining a gap which receives the end of an arm 4c 
mounted on the output shaft of a gear motor 18, for purposes described 
hereinafter. The machine section 17 also contains a drive mechanism for 
the various rollers, as will be described later. 
In a similar manner, the left-hand part of shaft 9 is axially slidable in a 
bearing block 20. A compression spring 21 surrounds shaft 9 between 
bearing block 20 and collar 9a attached to the shaft. The right-hand part 
of shaft 9 extends into drive section 17. 
The axially slidable left-hand parts of the shafts 4 and 9 as illustrated 
in FIG. 2 enable insertion and removal of the cores 5 and 10 between the 
respective chucks 11 and 13. 
As indicated by the dashed lines in FIG. 1, both the heated rollers 6 and 8 
and the upper ink transfer roller 7g throw off for easy threading of 
ribbon R and, to this end, the rollers 6 and 8 are mounted on swing arms, 
described hereinafter with reference to FIG. 3. 
The drive section 17 of the machine comprises a drive shaft 22 which drives 
roller 7c and which carries a gear 23 in mesh with a gear 24a driven by a 
main drive motor 24. A further gear train, not shown, is provided for 
rotating ink roller and 7e. Shaft 22 also carries a pulley 25 and a drive 
belt 26 passes about pulley 25 as well as about a pulley 27 carried on the 
right-hand end of shaft 9. Pulley 27 forms part of a clutch mechanism 
including a friction disc 28 and a further pulley 29. The clutch parts are 
urged together by a tension spring 30 disposed about shaft 9 between 
pulley 29 and an adjustable end stop 30a. A further drive belt 32 extends 
from pulley 29 to a pulley 31 carried by the right-hand part of shaft 4. A 
manually operable rewind crank handle 31a is also provided on the end of 
shaft 4. Both of belts 26 and 32 are crossed in their path between their 
supporting pulleys in order to provide the desired directions of rotation 
to pulley 27 and 31. 
In operation, motor 24 drives shaft 22 carrying roller 7c and also rotates 
pulley 25 thereby driving shaft 9 through belt 26 and pulley 27 to take up 
ribbon R on the core 10 held between the chucks 13. As ribbon R is wound 
about core 10, it is unwound from core 5 and rotates the shaft 4. 
Simultaneously pulley 31 rotates in the opposite direction by the back 
drive provided by pulley 29 and crossed belt 32 to take up slack in the 
ribbon feeding off core 5. The amount of back drive is adjusted by varying 
the tension of spring 30 on the clutch 27, 28, 29 by means of an 
adjustable end stop 30a, to provide a substantially constant winding 
tension and to compensate for variations caused by the changing diameter 
of the ribbon on the core as it is transferred from core 5 to core 10. 
Thus the clutch mechanism automatically controls the tension of the ribbon 
as it passes through the machine within a manual range of adjustment to 
ensure the desired tightness of ribbon R as it is wound on core 10. 
Consistent with this previous disclosure, the operation of the drive and 
tension mechanism will be more specifically disclosed. 
As is apparent from FIGS. 1 and 2, the ribbon is driven between ink 
transfer rollers 7d and 7g. Roller 7d is, in turn, driven by ink roller 7c 
(shown in FIG. 1), which is in turn driven by shaft 22. Therefore, the 
pulley 25, linked to ink roller 7c through shaft 22, rotates in a 
direction opposite that of shaft 9. As shown in FIG. 1, shaft 9 rotates 
counterclockwise to collect the ribbon on the take-up core 10. Therefore, 
the belt connecting pulley 25 with pulley 27 is twisted as shown in FIG. 2 
to reverse the direction between the two pulleys. In that manner, the 
drive from the motor 24, transmitted through the gear 23 to shaft 22 and 
pulley 25, is applied to the shaft 9, turning the take-up core 10 in a 
manner to exert tension on the ribbon. 
The shaft 4, on which the supply core 5 is detachably affixed, is driven by 
the unwinding of the ribbon from the supply core. Pulley 31, affixed to 
the shaft 4, rotates in the same direction as shaft 9 and the take-up core 
10. The pulley 31 is, however, linked to pulley 29, rotatably mounted on 
the shaft 9. As shown in FIG. 2, the belt linking pulley 29 and pulley 31 
are twisted to reverse the direction of rotation. Therefore, the rotation 
of shaft 9, transmitted to the friction material 28 between pulley 27 and 
29, resists the rotation of the pulley 31. 
The friction between the pulleys 29 and 27 transmits the force of the 
rotation of shaft 9 back to shaft 4, providing the back drive previously 
mentioned. Similarly, the rotation of the pulley 29, in opposition to the 
pulley 27, decreases the force applied to the take-up core 10 through the 
shaft 9. The tension, being balanced by the interrelationship of these 
driven shafts, is automatic since the slippage between pulley 27 and 
pulley 29 is predetermined by the tension in the spring 30. The length of 
the spring 30 is manually controlled but the slippage induced by the 
spring, once set, is constant. The tension in the ribbon, however, is not 
constant due to the different forces applied to shafts 4 and 9, 
respectively. 
The opposed rolls 7d and 7g drive the ribbon through the apparatus at a 
constant linear rate. As the supply core 5 is depleted of ribbon, its 
radius decreases. Therefore, its rotational speed increases. The increase 
in rotational speed provides an increased resisting force applied through 
the friction material 28 to the pulley 27. This decreases the tension 
applied to the take-up core 10. In that manner, the tension in the ribbon 
is automatically adjusted for the diameters of the ribbon on the 
respective cores. 
A photoelectric cell 34 carried by a mounting 35 is arranged to detect one 
edge of the ribbon R as it is fed through the machine and provide a signal 
to a control mechanism to maintain the alignment of the ribbon as it 
passes through the machine. 
More specifically, photoelectric cell 34 receives light from a light 
source, not shown, through a slit 35a in the mounting 35. The photocell 
controls a series of relays which in turn control the direction of 
rotation of electric gear motor 18. The arm 4c attached to the output 
shaft of this motor is thereby displaced and, since its free end is 
closely located in the gap between the collars 4b, this displacement 
causes axial movement of the shaft 4 in bearing block 16. This provides 
lateral or axial control over chucks 11 between which the core 5 is held 
under the force of spring 15. The direction of this lateral control is 
determined by the position of the edge of the ribbon R adjacent the slit 
35a in the mounting 35. If the lateral control is such that the edge of 
the ribbon covers the slit, light is cut off from photoelectric cell 34 
and it switches the relays to reverse the direction of rotation of the 
gear motor 18. The arm 4c is then moved in the opposite direction and 
hence shaft 4 is axially displaced to move the core 5 so that the edge of 
the ribbon uncovers the slit to again allow light to reach the photocell 
34. The system now reverses thereby providing constant correction to 
maintain the alignment of the ribbon as it passes through the machine. The 
constant correction previously noted is due to the fact that the edge 
detection means controls the direction of movement of the shaft 4 with the 
motor being activated at all times. This minimizes the time from the 
detection of the edges movement to actual adjustment of the equipment. A 
motor speed control is provided to compensate for different machine speeds 
and types and conditions of ribbon being handled. 
Means are also provided to automatically shut off the machine at the 
completion of the re-inking of a ribbon by increased tension on the ribbon 
when the end of the roll is reached. The torque required to achieve this 
is adjustable and also operates to detect loose or detective attachment of 
the ribbon on the core. This arrangement will now be described in 
conjunction with the throw-off arrangement for the rollers. 
The throw-off arrangement for the rollers 6 and 8 is illustrated 
diagrammatically in FIG. 3. This arrangement comprises an electric motor 
36 whose output shaft drives an arm 37 which is connected to the swing 
arms 38 and 39 carrying rollers 6 and 8 respectively. Once the ribbon has 
been threaded on the machine, the rollers 6 and 8 are moved into the 
running position, shown in full line in FIG. 1, by rotation of the 
electric motor and the arm 37 on which the swing arms are mounted. 
In the running position, rollers 6 and 8 deflect the ribbon in its passage 
through the machine and are held in this position by an adjustable torque 
control 40 on motor 36 until the ribbon is completely unwound from the 
core 5. At this point the tension of the ribbon R on rollers 6 and 8 
increases and causes the torque control 40 to break loose, thus rotating 
the swing arms 38, 39 to throw off the rollers 6 and 8 towards the 
threading position (shown by the dashed lines) and thereby creating slack 
in the ribbon. The main drive motor 24 is energized through a limit switch 
which is only closed when the rollers 6 and 8 are in the running position. 
The main drive motor will thus stop as soon as torque control 40 breaks 
away and the slack created by this allows the ribbon to stop without 
pulling away from core 10. If the ribbon attachment to core 5 is 
defective, the ribbon will pull away from the core. However, the ribbon 
can then be easily re-anchored to the core to prevent it from coming loose 
and causing problems during its subsequent use in a printing apparatus. 
It will be noted that both sides of the ribbon are re-inked under pressure 
with a relatively large arc of the ribbon in contact with a pre-metered 
layer of ink on the surface of the transfer rollers 7d, 7g on both sides 
of the ribbon. The pressure between these rollers impregnates the ink into 
the interstices of the fibers and is arranged to be adjustable. Moreover, 
the inking station 7 provides for accurate metering of the ink by the 
metering rollers 7h, 7j associated with each ink trough 7b, 7f. 
The heating elements associated with each of the heated rollers 6, 8 allow 
the temperature of the rollers to be adjusted within the range 100.degree. 
to 300.degree. F. 
A fluorescent lamp 41 mounted in a reflector 42 transverse to the path of 
the ribbon R is arranged to shine light through the processed ribbon 
between roller 8 and core 13 so that the re-inked ribbon can be visually 
inspected by an operator viewing the ribbon from the other side. 
It will be seen that the present invention provides a method and apparatus 
wherein re-inking of a ribbon can be accomplished from the front of the 
machine with all adjustments within easy reach. Furthermore, the ink 
reservoirs are large and have automatic ink level control re-circulation 
to cool and filter the ink. When not in use the inking rollers are easily 
separable to prevent spots occurring on the rollers and the rollers and 
ink pans can be easily removed for cleaning or replacement. 
If desired, the transfer roller 7g can be made adjustable so that it does 
not apply ink to the ribbon, but is only inked on one side by the lower 
transfer roller 7d. Such an arrangement may be preferred for the re-inking 
of light-weight ribbons. 
Generally, the ribbons to be re-inked will be nylon ribbons. Ribbons of 
other materials, of course, may also be treated. 
The method and apparatus of the invention may also be employed for 
initially inking fresh ribbons as well as for re-inking used ribbons as 
described herein. 
The invention may be embodied in other specific forms without departing 
from the spirit or essential characteristics thereof. The present 
embodiment is therefore to be considered in all respects as illustrative 
and not restrictive, the scope of the invention being indicated by the 
appended claims rather than by the foregoing description, and all changes 
which come within the meaning and range of equivalency of the claims are 
therefore intended to be embraced therein.