Improvements in or relating to Typewriting Machines.
Year: 1899

page_text: Date of Application, 31st Jan.. 1899 -Accepted, 1st Apr., 1899
Improvements in or relating to Typewriting Machines.
A communication from Charles SPIRO, of 116th Street, Fifth and Lenox Avenues,
New York, United States of America, Gentleman.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of London,
Chartered Patent Agent, 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:-
This invention relates to improvements in typewriting machines, and has especial
reference to the mechanism for operating the inking ribbon.
The various mechanisms at present in use for automatically reversing the direction
in which the ribbon travels from one spool to the other, are open to several
objections, among which may be mentioned the following:-The entire ribbon
cannot be used, the latching of the spools is not very secure, the working parts
are exposed to dust from erasures &c. and are therefore liable to become clogged,
and the mechanism and its adjustment are complex and hence if a part has to be
renewed much trouble and difficulty are incurred.
These disadvantages are obviated in the mechanism herein described, which is
simple in construction, and of few parts, which are large and easily replaced;
practically the whole length of the ribbon may be used, and the working parts are
not likely to become clogged with dust.
In the accompanying drawings which illustrate one construction of ribbon
mechanism according to this invention applied to a bar-lock machine.
Figure 1 is an elevation of the mechanism looking from the back of the
machine, and
Figures 2 and 3 are side elevations of the same looking in the direction of the
arrows 2 and 3 in Figure 1 respectively.
Like letters indicate like parts throughout the drawings.
A is an oscillating ribbon carrier mounted upon a pivotted bar which is moved
by the key levers, one of the latter being indicated at B¹. The oscillation of the
ribbon carrier A causes a spring controlled pawl A¹ to rotate a ratchet wheel C¹
mounted at the centre of a shaft C, which also carries two pinions C2 one at each
end, these pinions serving to rotate the ribbon spools. The ratchet wheel C is
controlled by a spring detent C³. These features are all found in the bar-lock
ribbon mechanism now in use, and form no part of the present invention.
The pinion shaft C is carried in bearings in lugs or extensions D¹, forming part
of a plate 1), pivotted as by a screw 12 to a standard E rigidly fixed to the
frame-work of the machine. The plate D with the lugs D' forms a shield or guard
which tends to keep erasure dust from passing down at the back of the machine
into the pinions C³. The ribbon spools F the sides of which are provided with
teeth on their peripheries as at F, slip on to pins F carried by the standard E,
and are so placed that the teeth F¹ upon the inner side of the spools will gear with
the teeth of the adjacent pinion when the plate D is tilted in the proper
Hirection. The ribbon spools are kept in position by levers G pivotted as at G¹,
and provided with springs G2 which cause the levers to press against the ribbon
apon the spool and thus to act as brakes.

page_text: H are reversing levers pivotted as at H¹ and actuated by springs H2 upon the
pins these levers H are each controlled by an extension G³ upon the adjacent
brake lever G, and their function is to tilt the pinion plate D so that the
pinion on the same side as the operating reversing lever H is thrown into gear
with its ribbon spool F.
In order that the pinion and ribbon spool when thrown into gear shall continue
in that condition as long as required, locking levers J are provided, pivotted
about the same centres H as the reversing levers H, and having hooks which
engage with a recess D3 in the top of the pinion plate D. Each of the locking
levers J has a lateral projection J which is operated by the extension of the
brake lever G; and the locking levers J and the reversing levers H are provided
with projections J³ and H³ respectively, which are accommodated in, and operate
upon slots or recesses 1 in the pinion plate 1). In order that, as hereinafter
described, the direction of travel of the ribbon may, if desired, be manually instead
of automatically reversed, the locking levers J are provided with handles J
extending upwardly from them.
The operation of the improved mechanism is as follows:-
Assuming that, as shown in Figure 1, one of the ribbon spools F has become
filled with the inking ribbon F3, the pinion plate D is, by the action of the reversing
lever Hupon the opposite side to the full bobbin, tilted, and the full bobbin
thrown out of gear while the empty one is thrown into operation; this condition
of affairs is clearly shown in Figure 1, and the steps which lead up to such a
position are as follows:-
As the brake lever G (Figure 2) is forced outwards by the increasing diameter
of the roll of ribbon on the spool F, its extension G operates the reversing lever H,
and rotates it against the action of its spring H2, thus causing it to be inoperative
upon the plate D. On the other hand, the brake lever G upon the other side
(Figure 3) gradually approaches the hub of its ribbon spool, consequently its
projection G ceases to control the reversing lever H, and the latter is therefore
subjected to the full force of the spring H2, and therefore tends to rotate and by
its projection H to tilt the pinion plate D. This, however, cannot happen until
the brake lever G has still further approached the hub; when it has done so its
extension Goperates upon the portion J of the locking lever J and rotates the
latter, causing the hook J to be lifted out of engagement with the recess 13 in the
pinion plate D. As soon as this occurs the force of the spring H³, acting
upon the reversing lever H, throws the pinion plate Dover and places
the empty spool in gear. The pinion plate 1) is secured in its new position by the
other locking lever, the hook Ji of which falls by gravity into the recess D³. The
ribbon is now wound off the full bobbin on to the empty one and the cycle of
operations repeated.
If it is desired to reverse the direction of travel of the ribbon by hand, the handle J
of the locking lever adjacent to the spool which is to be thrown into operation
is moved backwards, this lifts the hook J¹ from engagement with the recess D³,
and also causes the projection J3 to tilt the plate D over into the new position where
it is locked by the hook J¹ of the other locking lever.
It will be apparent that the various parts forming this mechanism can nearly
all be readily and cheaply formed by pressing, stamping, or similar process, from
sheet metal, and the parts being comparatively large are easily assembled and not
at all liable to derangement.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what
manner the same is to be performed I declare that what I claim is:
1. In the ribbon mechanism of a typewriting machine the combination with a
pivotted plate such as I carrying the pinions of two independent spring-actuated
reversing levers H each operating one side of the plate substantially as described.
2. In the ribbon mechanism of a typewriting machine a lever such as G acting

page_text: Drake upon the ribbon and controlling the reversing and locking levers
substantially as described.
3. In the ribbon mechanism of a typewriting machine the combination with a
pivotted plate D of a locking lever J having a hook J¹ and a projection J³ arranged
and operating substantially as described.
4. In the ribbon mechanism of a typewriting machine a pivotted plate 1 having
portions D¹ bent over to carry the ends of the pinion shaft C and so shaped that
it forms a shield or guard to prevent clogging of the pinion teeth substantially as
described.
5. The combination and arrangement of parts constituting the complete ribbon
mechanism for a typewriting machine substantially as described and illustrated in
the accompanying drawings.
Dated this 30th day of January 1900