Improvements in Type-writing Machines.
Year: 1897

page_text: Date of Application, 6th July, 1897-Accepted, 14th Aug.,
1897
COMPLETE SPECIFICATION.
Improvements in Type-writing Machines.
I JOHN THOMAS UNDERWOOD, of 99 St. James' Place, Brooklyn, Kings County,
State of New York, United States of America, Manufacturer do hereby declare
the nature of this invention and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement:
My invention relates to type-writing machines and has for its object to produce
a machine wherein ribbons or inking devices of various characters may be inter-
changeably used and at will.
To this end my invention consists in the construction and arrangement of
devices hereinafter particularly claimed in the claiming clauses.
My invention will be understood by referring to the accompanying drawing,
in which
Figure 1 is a plan view of a typewriter embodying my invention in which the
inking device comprises a rotary and reciprocating sheet:
Figure 2 is an enlarged detail sectional view of the operating mechanism
therefor;
Figure 3 is a section on line 3-3 of Figure 2;
Figures 4, 5 and 6, show the detachable inking sheet in detail, as will be
explained;
Figure 7 is a plan view of another typewriter embodying my invention;
Figure 8 is an enlarged broken away detail plan view of the reciprocating inking
sheet carrier;
Figure 9 is a vertical lateral section thereof; and
Figure 10 is a vertical longitudinal section thereof.
Referring to Figures 1 to 6, A indicates the frame of a typewriter machine
carrying a winding shaft a, upon which bevel gears b, c, are carried. B is the
carriage, of the machine which moves on the back and front rods D, E, in the
usual maner. This movement is effected during manipulation of the keys by
the carriage spring barrel Cand a strap connection f intervening between the
said spring barrel C and carriage B. This operation is well understood and need
not be further described. Carried by the shaft of the spring barrel C is a bevel
gear 9 which meshes with the gear 6 on the winding shaft a.
Mounted upon the
top plate D of the typewriter is a plate E which is provided with guides h, h,
between which guides passes a slide i carrying at or near one end a pin upon
which a circular gear wheel k is journalled. The slide i is slotted as at 7 for the
passage of a vertical shaft m, which carries a gear wheel n at its lower end, which
gear wheel meshes with the bevel gear o on the shaft p, which also carries a
gear 9 (Fig. 1) meshing with the gear on the winding shaft a.
Mounted upon
the upper end of the shaft m is an elliptical gear wheel r. In the present instance
this gear r closely approximates the circular form and is eccentrically mounted on
its shaft m. This gear wheel meshes with the circular gear wheel k, and is pro-
vided with a pin s, which is connected to the slide by means of a link t, which
is pivoted by the pin to the slide and works freely on the pin s. G is the
printing agent, which may be in the form of the usual type bar now employed.

page_text: Mounted and secured upon the gear so as to rotate therewith is the inking
device shown in the present instance as a plate or disk II (Figs. 4, 5, 6) of textile
fabric intervening between the printing agent and the impression roller or platen J
of the machine. For this purpose. I preferably employ a flimsy edge stiffened
inking sheet. This sheet is preferably connected to the disc by pins extending
upwardly from the wheel and entering apertures h' in the disk H.
As the operation of the other parts is well known, I will describe simply the
operation of the shifting mechanism for the inking device. As before explained,
the inking device His carried by the wheel k, and as the shaft is rotated, the
shaft P will be thereby rotated, also rotating the vertical shaft m, which carries
with it the elliptical wheel r. The elliptical wheel carried by the vertical
shaft m will rotate the wheel &, thereby also rotating the inking device H, and will
also in addition impart to the wheel and inking device carried thereby a motion
of translation, by reason of the fact that the wheel is eccentrically mounted on
its shaft and the wheel with which it meshes is carried by the freely movable
slide i. It is also to be observed that for every rotation of the inking disc the
said disc will be reciprocated back and forth only once; hence the motion of
rotation or peripheral speed of the disc will be faster than the bodily movement
of translation or reciprocation, that is to say, the disc will rotate at a relatively
fast rate of speed and the displacement of the centre of rotation thereby will
occur at a relatively slow rate of speed, the link connection between wheel r and
the slide serving to return the slide and wheel when has turned into such
position as to push to its greatest distance from the centre of rotation of r.
It will be obvious that as the point of strike of the printing agent or printing
point will always be in the same place, the combined rotation and reciprocation
of the disk will cause the printing agent to strike the said disk along paths which
are eccentric to the axis of rotation of the disk. These paths, which I denominate
the paths of travel of the inking-device, will lie within an annulus whose width
will depend upon the extent of reciprocating motion imparted to the disk. This
is clearly shown in Figure 5, wherein a disk II is shown having a zone or annulus
bounded by concentric circles 1, 2, whose distance apart depends upon the extent
of throw of the elliptical wheel r.
د"
In the present instance, owing to the fact that the wheels and have not the
same number of teeth (one having 70 teeth and the other 72 teeth) there will be 35
of these paths intersecting each other, so that in order that any given point in the
disk may be moved from the printing point and returned to it, it would be
necessary to effect 35 revolutions of the disc.
The preferred form of disc employed by me is shown in Figure 4, wherein the
said dise H is stiffened at its edge 3 and at the points 5, 6, 7, surrounding the
apertures left for the passage of the pins of the carrier wheel k.
The modification shown in the remaining figures comprises as in the preceding
figures a reciprocating carrier for the inking sheet, but whereas in the former case
the reciprocating carrier for the inking sheet is reciprocated by the movement of
the type bars, in this latter case the reciprocating carrier is moved by hand so
as to introduce the inking carrier into or remove the same from the field of strike
of the type, leaving it in the position to which it has been reciprocated without
interfering with the mechanism for rotating the said inking sheet. It will be
obvious that in this case, as well as in the former case, the inking sheet may be
of a different colour from the ribbon or may be un-inked and interposed between
the type and the ribbon carrying ink so that the types will strike an un-inked
sheet and will not fill or clog with ink or gummy matters on the inking sheet.
In Figures 7, 8, 9 and 10, I have illustrated my invention in connection with
the ordinary form of typewriter such as that sold under the title of the Remington
Typewriter, or it may be employed with any machine wherein a printing sheet
is employed, in substantially the same manner.
In these figures, A represents such a type writing machine as I have described. u¹
is the table of the machine; a² is the gang of type bars of which is one of the

page_text: levers and one of the type and one of the levers leading to the bank of
keys, and a is the spacing lever leading to the space bar 8. The ink, ribbon a
passes through apertures in the table a¹. Set screws
are set in the
table al for the purpose of holding my attachment in position. I have deemed it
unnecessary in this connection to show the other operative.features of, the machine
which are unnecessary for the purpose of illustration here.
1
a
I will now proceed to describe the details of the construction of my attachment:
is a cross bar provided with the slots and, which are arranged to slide
under the set screws a¹ and 12, and to be held upon the table a' by said set screws.
Referring to Figure 10 it will be seen that this bar bis provided with the upturned
right-angular flange 62, which flange is again hent at right-angles as at 3, and
on the other side the bar is also provided with flange bent at right-angles
thereto, and the flange bent at right-angles to the flange b', thus forming
base on which the carrier of the attachment is mounted, of a width substantially
equal to that of said carrier, and also providing a space for the operative
mechanisms which I call the trigger movement of my device, as shown in section
in Figure 10 along the lines of Figure 9; this trigger movement of my
device may be described as follows: 66 is a plate provided with the slots or ways
and, through which the plate 16 is secured to the flange by the screws 8
and 8, but said screws are introduced only far enough to operate as guides for
the plate 6, and 10 is a binding post on the base plate or brace b', and b is a
binding post secured to the plate 66; between said binding posts 6 and 10 is
interposed a spiral spring with its tension-directed to maintain the plate 66
in the position shown in Figure 9 is a chain secured to the binding post b
and passing over the pulley 65, and secured to the spacing lever a, and operated
thereby, as heretofore described. A lug forming part of the plate. passes
through an aperture in the plate 17, hereafter to be described, and operating on
the lever 21 is a staple secured to the base plate or brace, and is a
pulley mounted on a spindle secured to said staple 64; 6 and 66 are set screws
for the purpose of elevating or lowering the attachment with reference to its
position between the type and the platen. 17 is a plate, which I prefer to call a
carrier upon which is mounted the operative mechanisms of my device, for moving
the printing sheet, it is provided with a right-angular flange 18, through, which
passes a thumb screw which is intended for the purpose of adjusting the
throw of the device, and 620 is a lock nut to fix said throw when the same is
determined by the thumb screw 619; 621 and 621 are slots in the plate and 622
and are screws to hold said plate 617 to the flanges 65, and 3 of the base plate 61;
these screws are sufficiently loose to permit the carriage to slide withinatho
ways 61 and 621; 623 is an aperture within the plate 617 to permit the lug or
trigger to pass through the same and operate freely within said aperture.. 624
and 626 form a crank lever pivoted at 625 said crank arm 626 being pivotally, con-
nected with the lever 62, which is provided at the other end with the pawl 29,
and the guide 628 is interposed to hold said lever 627 in position. 630 is a lug
secured to the plate 17, and is a knife spring secured to the binding post 62,
bearing on the lever 62+, at the point 63, for retaining the same against the post 630
The lever is provided with the aperture 6 to permit the lug or trigger 613 when
my attachment is withdrawn from operative position, to respond to the movement
of the space bar without operating my attachment. 65 is a ratchet wheel secured
to the spindle 36, which passes through a journal bearing in the plate 6. 637
is a metal disk employed to support the printing disk. i
I prefer in operation to interpose beneath the printing.idisk a .supplementary
disk of thin tough material, such as gold,beatersomembrane, which is intended to
separate the printing disk from the direct action of the type, and also where an
ink ribbon such as al is also used in the machine to prevent the marring of the
printing disk by the ink of the ink ribbon. It will be understood that I present
to the paper to be impressed, that side of the printing sheet, which is most favorable
for the transmission of the ink to the paper. I secure my attachment to the table

page_text: of the typewriter by the screws a¹³ and a¹², passing into the slots 65 and 6². I
may partially adjust the same in these slots, so as to bring the attachment in the
right position. I so adjust my attachment with reference to the operative field
of the type, that when the device is drawn back in the position shown in Figure 7,
the printing disk will be out of the field of the type, and when it is thrown forward,
it will be within the field of the type; this adjustment may be facilitated by the
operation of the thumb screw 19, and the set screw 620. I find this adjusting
device also convenient when it is desired to shift the printing surface of the
printing sheet, so as to bring a new surface into operation, when one surface is
partially exhausted; I then secure the chain 612 to one of the spacing levers con-
nected with the spacing bars, as a. When my attachment is thrust forward,
that is to say, when the carriage 617 is caused to move in the slots 21 and 621 into
the position shown in dotted lines in Figure 7, the trigger 613 is in position to
engage the crank lever 624, and with the operation of the space bar from time to
time, as the typewriter is operated, the plate 66 carrying said trigger 613 is caused
to reciprocate first by the power of the spacing bar, and it is then retracted by the
spiral spring. With the movement of the said plate and trigger in the power
of the said spacing bar, said trigger engages the crank lever 624 and causes
the ratchet 29 to engage the ratchet wheel 65, thus moving the printing disk one
step, and thus presenting to the type a fresh printing surface. When, however,
the carrier 17 is retracted, the trigger 6, responding to the movement of the space
bar moves within the slot 64 of the lever 62; thus the movement of said trigger
during the period that the carrier 617 is withdrawn is an idle movement, that is to
say, it does not affect the lever 624, and therefore the printing disk is stationary.
I may employ my device either singly or in duplicate, or I may use either one
or two attachments in association with the ordinary inking ribbon of a typewriter
or without such ribbon as convenience may dictate. The advantage of using
several printing sheets is, that I may employ printing sheets of different colours,
or having different qualities, that is to say, some printing sheets are prepared
with inks or coloring matters that will duplicate in an ordinary letter copying
book, while others have the quality of being indelible, and not capable of copying.
With the ordinary arrangement of the typewriter ribbon, it is necessary when it
is desired to use a copying ribbon or non-copying ink, or to introduce a new colour,
either to reel off the copying ribbon and introduce another or to carry two on
the reels, thus necessitating the winding and the unwinding of the reel with each
change. My device is intended to provide a convenient means of rapidly changing
the printing sheet and readily introducing another. Moreover, in the ordinary
printing ribbon only a limited part of the ribbon, that is to say, usually the centre
thereof, is brought into the field of the type, whereas with the arrangement that I
have shown by the adjustment of the thumb screw 619, I may bring substantially
the whole of the printing surface of the disk employed into the field of the type.
Moreover these disks may be introduced and removed with great readiness and
facility. Furthermore, I may use a disk made of materials which could not be
used as an ink ribbon, because of their lack of tensile strength.
Furthermore, my attachment is capable of very convenient economical use in
connection with what is known as the mimeograph process of duplicating type-
written matter. As the mimeograph process is at present operated, the ink ribbon
is first removed. Under the present arrangement of typewriters this requires the
unreeling of the ribbon, and the removal of the same from the field of the type,
for it is necessary in that process to bring the type directly in contact with the
wax sheet from which it is desired to make a stencil. In the operation of my
device, all that is necessary is to withdraw the carrier of the attachment so as to
remove the printing sheet from the field of the type; this done, the machine is ready
to receive the wax sheet which is employed in the preparation of the stencil used
in what is known as the mimeograph process.
I may employ as the printing sheet to be used as my attachment, any of the

page_text: well known printing sheets, which may be used for this purpose, but I prefer to
use a thin paper as this is more economical.
It will be obvious that several of the described devices may be employed upon
the same machine so as to enable the operator to employ one or the other of these
at will, so that by employing sheets of different colours, different colored writing
may be employed at will.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a typewriter machine, the following instrumentalities, namely, a printing
agent combined with an inking disk and means for moving the inking disk in
one plane.
2. A typewriter machine consisting of a printing agent combined with an inking
disk and with means for rotating the disk as and for the purposes set forth.
3. A typewriting machine consisting of a printing agent combined with an
inking disk intervening between the printing agent and an impression surface and
with means for moving the disk in one plane.
4. In a typewriter machine, the combination of a printing agent, an impression
surface, an inking disk intervening between the impression surface and the printing
agent, and means for rotating and shifting the disk.
5. A shifting mechanism for inking devices consisting of a gear as k, an eccen-
trically mounted elliptical gear as meshing with the gear k and a connection
between the gear r and the gear k, whereby upon rotation of the gear r, the gear k
will be rotated and displaced.
6. The combination of a slide, a gear carried thereby, an eccentrically mounted
elliptical gear meshing with the first mentioned gear and a connection between
the elliptical gear and the slide for moving the slide.
7. A typewriter organization comprising a printing agent and platen combined
with an inking plate or disk, means for rotating the disk and mechanical means
for imparting a reciprocating motion to the centre of rotation of the disk.
8. A typewriter organization comprising a printing agent and platen combined
with an inking disk, means for rotating the inking disk and mechanical means
for producing a reciprocating motion to the centre of rotation of the inking disk
along a rectilinear path.
9. A typewriter organization comprising a printing agent, key levers and a
platen, an inking disc, means for rotating the said inking disc and means for auto-
matically displacing the axis of the inking disc by means of the action of the key
levers in such a manner that successive portions of the disk will be presented to
the printing point, said successive portions lying in an annular space between
circles concentric with the centre of rotation of the disc.
10. A typewriter organization comprising the following instrumentalities in
operative combination, to-wit; a printing agent and platen, an inking disc, means
for rotating the disc in a relatively rapid rate of speed and means for automatically
displacing the centre of rotation of the disc at a relatively slow rate of speed by
means of the action of the key levers, whereby the printing agent will be made
to act upon curves lying eccentrically within a ring on the disc which ring 1
concentric to the centre of rotation of the disc.
11. The here in described new and useful improvement in inking devices for
typewriter machines, the same consisting of a substitute for existing inking devices
comprising a sheet or disc of textile fabric provided with means for co-operating
with propelling devices, as and for the purposes set forth.
12. An inking device consisting of a sheet of textile fabric stiffened at or near
the edge, substantially as described.
13. As a new and useful article of manufacture, the herein described improve-
ment in inking devices consisting of a sheet or disc provided with a stiffener and
perforated for co-operation with propelling means.

page_text: 14. In a typewriting machine the combination with a type and platen, of an
inking sheet suitably mounted on a reciprocating carrier to move said sheet into
and out of the operative field of the type, substantially as described.
15. In a typewriting machine the combination with the type and platen, of an
inking disk suitably mounted on a reciprocating carrier, to move said disk into
and out of the operative field of type, and means operated by the typewriting
machine, to rotate said disk, substantially as described.
!
16. In a typewriting machine, the combination with the platen, of an inking
disk suitably mounted on a reciprocating carrier to move said disk into and out.cf
the operative field of the type, and means operated by the movement of the
typewriting space-bar to rotate said disk, substantially as described.
17. In a typewriting machine the combination with the type and platen, of an
inking disk suitably mounted on a reciprocating carrier to move said disk into
and out of the operative field of the type, said disk being secured to the carrier
by a spindle having at one end a ratchet wheel, with a pawl for said ratchet, and
a trigger engaging said pawl, operated by the movement of the machine to rotate
said disk, substantially as described.
"
18. In a typewriting machine the combination with the type and. platen, of an
inking disk suitably mounted on a reciprocating carrier, to move said, disk into
and 'out of the operative field of the type, said disk, being mounted on said carrier
by means of a spindle having at one end a ratchet wheel, with a pawl for said
ratchet and a trigger engaging said pawl while the disk is in the field of the type,
said trigger being operated by the movement of the machine, substantially as
described.
19. In a typewriting machine the combination with the type and platen, of an
inking disk suitably mounted on a carrier, said carrier being mounted to recipro-
cate on a frame secured to the top plate of the typewriter machine, at either site
thereof, to move the disk into and out of the operative field of the type, said disk
being mounted on said carrier by means of a spindle having at one end a ratchet
wheel with a pawl for said ratchet and a trigger engaging said pawl while the disk
is in the field of the type, said trigger being operated by the movement of the
space-bar, substantially as described.
20. In a typewriter, the employment of a printing disk movable into and out
of the field of strike of the type.
21. In a typewriter, the employing with an ordinary inking means of a sheet
movable into and out of the field of strike of the type and adapted to be either
interposed between the inking device and the. platen or between the type and the
inking device.
22. In a tewriter, the combination of a plurality of movable inking devices
of different colours capable of being moved into and out of the operative field of
the tone for the purposes set forth.
!