IMPROVEMENTS IN TYPE-WRITING MACHINES
Year: 1880

page_text: "
LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for an Invention of IMPROVEMENTS IN
TYPE-WRITING MACHINES." A communication from abroad by Albert Mendes
Da Costa, of Brooklyn, in the County of Kings, State of New York, United
States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 28th September 1880.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN TYPE-WRITING MACHINES." [A communication
from abroad by Albert Mendes Da Costa, of Brooklyn, in the County of Kings,
State of New York, United States of America.]
The object of this Invention is to provide type writing machines with means for
enabling the operator to write much more rapidly than with the machines at
present in use, to avoid the clashing of two or more type levers, and blurred
impression of the type, and to obtain a uniform spacing of the letters.
The Invention consists in a band, string, or wire, which alternately passes
through staples or apertures in the key levers, and in rigid supports above or
between said key levers, said band or wire being furnished with means for adjusting
its tension so as to leave sufficient slack only to permit one key lever to be entirely
depressed at a time, and so also that if two keys should be struck at the same
time the band will prevent both from being raised sufficiently to clash against each
other.
The staples or eyes, which may be attached either to the upper or lower edge of
the levers, consist of a simple wire loop driven into the said levers or attached in
any other suitable manner, or of a wire held by metal bands and preferably
provided with a sleeve loosely mounted on the cross piece of said staples to reduce
the friction caused by drawing the bands or cords through the said staples and to
prevent chafing and cutting of the string or band. Between every two levers a
like staple or eye is attached to the underside of a transverse frame or rail
arranged directly above and adjacent to the key levers, or the above or any other
suitable kind of staple may be attached to a series of partitions or standard s

page_text: between the key levers, and all the staples on the key levers and on the rail or
standards are preferably arranged in the same vertical plane. The band or ribbon
is alternately passed through the staples on the key levers, and through the staples
on the transverse rail, or the partitions, so that the cross pieces of the several staples
are alternately below and above the said ribbon, which is attached to one or more
ratchet rollers, or other suitable devices, by which the tension of the said band can
be regulated. The ratchet rollers may be attached to the side of the frame of the
machine so that they can be operated conveniently. The band may be replaced by
a string, wire, strong silk thread, or cat gut, or other suitable material, which
alternately passes through the staples of the key levers and the staples of the
frame or partitions, or over a series of grooved discs loosely mounted on pins on
the sides of the transverse frame or rail, or on the front or rear sides of the
partitions or standards. The tension of the string or wire may be regulated by
means of one or two externally threaded tubes in which the ends of said strings
are secured. These tubes may rest in the sides of the frame of the machine, and
are provided with thumb screws or other device for turning them. The string may
also be alternately passed through the staple, eyes, or perforations in the key levers
and perforations in the standards.
The tension of the band or string is regulated so as to permit but a single key
lever to be depressed sufficiently to allow the type end of but a single type hammer
to touch the printing cylinder at a time, the band being drawn so taut that no
other key lever can be depressed, and if that should be attempted the key lever or
the band would break. If two key levers are depressed at the same time under
equal pressure the corresponding two type hammers will both be raised half way
only, and as long as the pressure on the two keys is equal they must remain in
this position, but as soon as the pressure on one key lever is increased the
corresponding type hammer will rise in proportion, whereas the other will descend.
One lever must rise as rapidly as the other descends, and consequently one type
hammer must descend as rapidly as the other ascends, thus producing elegant
writing, the spacing by this action being exact. The operator need not wait until
a type hammer drops by its own weight before raising another, but the more
rapidly the hammers are raised, with equal rapidity they will descend. The tension
of the band or string prevents the type hammers from being raised higher than up
to the printing cylinder, so that the blurring of letters now common from indentation
by the type when writing rapidly is obviated.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
28th March 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
"IMPROVEMENTS IN TYPE-WRITING MACHINES." A communication
from abroad by Albert Mendes Da Costa, of Brooklyn, in the County of Kings,
State of New York, United States of America.
The object of this Invention is to provide an improvement in type writing
machines, by which the operator is enabled to write much more rapidly than with
the ordinary type writing machine in use at present, and whereby the clashing of
two or more type levers or blurred impression of the type are avoided and a
uniform spacing of the letters is obtained. The Invention consists in a band,
string, or wire, which alternately passes through staples or apertures in the key
levers, and in rigid supports above or between said key levers, which band or string
can be drawn as taut as may be desired by means of ratchet rollers; thus it is
adjustable so as to leave sufficient slack only to permit one key lever to be entirely
depressed at a time, and so also that if two keys should be struck at the same
time the band will prevent both from being raised sufficiently to clash against each
other.
In the accompanying Drawings Figure 1 is a cross sectional elevation of the
mechanism of a type writing machine provided with the improvement, showing one
type hammer raised; Figure 2 is the same view, showing two type hammers
partially raised; Figure 3 is a cross sectional elevation through the key levers,
showing one of said levers depressed; Figure 4 is a cross sectional elevation of a
modification of the improvement, showing all the key levers at rest; Figure 5 is a
cross sectional elevation of another modification, showing one of the key levers
depressed; Figure 6 is a detail side view of the staples on the key levers; Figure 7
is a detail view of a modification of said staples. Similar letters of reference
indicate corresponding parts.
The key levers A, A, of a type writing machine are provided with staples or
lengthened eyes B, which may be attached to the upper or lower edge of said
levers, as shown in Figures 6 and 7 respectively. These staples may consist of a
simple wire loop driven into the said levers, or attached in any other suitable
manner, or may consist of a wire held by metal bands, as shown in Figure 6, and
are preferably provided with a sleeve C loosely mounted on the cross piece of said
staples to reduce the friction caused by drawing the bands or cords through the
said staples, and to prevent chafing and cutting of the string or band. Between
every two levers A a like staple or eye K is attached to the underside of a
transverse frame or rail D, arranged directly above and adjacent to the key
levers A, or the above or any other suitable kind of staple E may be attached to a
series of partitions or standards F between the key levers and all the staples on the
key levers, and on the rail D or standards F, are preferably arranged in the same
vertical plane. A band or ribbon G, of any desired suitable material, is alternately
passed through the staples on the key levers and through the staples on the
transverse rail or the partitions, so that the cross pieces of the several staples are
alternately above and below the said ribbon G, which is attached to one or more
ratchet rollers H, or other suitable devices, by which the tension of the said band
can be regulated. The ratchet rollers may be attached to the side of the frame of
the machine so that they can be operated conveniently. The band G may be
replaced by a string, wire, strong silk thread, or catgut J, or other suitable material,
which alternately passes through the staples B of the key levers and the staples K

page_text: or E, or over a series of grooved discs L, which are loosely mounted on pins on the
sides of the rail D, or on the front or rear sides of the standards F, as shown in
Figure 5. The tension of the string or wire J may be regulated by means of one
or two externally threaded tubes M, in which the ends of said strings are secured
in some suitable manner. The threaded tubes M may rest in the sides of the
frame of the machine, and are provided with thumb screws N, or other suitable
device for turning them. The string may also be alternately passed through
the staple, eyes, or perforations in the key, levers, and perforations in the
standards F, F.
The operation is as follows:-The tension of the band G or string J is regulated
so as to permit but a single key lever to be depressed sufficiently to allow the type
end of but a single type hammer O to touch the printing cylinder P at a time,
that is, the band or string has just so much slack that if one key lever is depressed
the staple of said lever will draw down the band or string, as shown in Figures 1,
3, and 5, taking up all the slack of said band or string, which is thus drawn so
taut that no other key lever can be depressed, and if that should be attempted the
key lever or the band would break. If two key-levers are depressed at the same
time under equal pressure the corresponding two type hammers O¹ and O³ will
both be raised half way, as shown in Figure 2, and as long as the pressure on the
two keys is equal they must remain in this position, for if the entire slack of the
band or string is taken up to raise one type hammer to the printing cylinder,
then the two key levers must share the slack equally, and then it is evident that
they can only be raised half way. But as soon as the pressure on one key lever is
increased, the corresponding type hammer will rise in proportion, whereas the other
will descend. It is evident that two or more type hammers cannot be raised at the
same time, and thus all clashing of the hammers is entirely avoided if they are so
selected in size that they will naturally pass each other at half stroke. As stated
above, if two type hammers are partially raised, as shown in Figure 2, one of them
can only be raised entirely if the other descends entirely; or, in other words, if one
key lever, for instance A', Figure 3, has been depressed, no other lever can be
depressed until the lever A' is released, and as soon as that is the case the lever
that is depressed next, for instance A³, will take up the slack of the band or string
and necessarily raise the lever A³, and it is seen from the above that one lever
must rise as rapidly as the other descends, and consequently one type hammer
must descend as rapidly as the other ascends, thus producing elegant writing, the
spacing by this action being exact. The operator need not wait until a type
hammer drops by its own weight before raising another, but the more rapidly the
hammers are raised with equal rapidity they will descend. A person is thus
enabled to write with about twice the speed attainable with type writers in use
heretofore, and the writing will be very regular and will not be marred by the
irregularities caused by the clashing of the type hammers; and further, the tension
of the band or string prevents (the type hammers from being raised higher than
up to the printing cylinder, and consequently the blurring of letters now common
from indentation by the type when writing rapidly is obviated.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
hereinbefore in part recited Letters Patent is,―
1st. In a type writer, a band or equivalent passing through staples or eyes on the
key-levers and on a frame above or between the key-levers, and held or checked
rigidly by stationary supports, all said parts being combined substantially as shown
and described.
2nd. The combination with the key levers A of the staples B, K, transverse
rail D, or an equivalent, ribbon G, and a tension adjusting device fastened to rigid
supports, substantially as shown and described.
3rd. In a type writing machine, the combination with the key levers A of the
staples B and K, the ribbon G, and the ratchet rollers H, the ribbon being attached

page_text: to the rollers, substantially as herein shown and described and for the purpose set
forth.
4th. In a type writing machine, the combination with the key levers A. of the
staples B and E, the standards F, and the string or wire J, substantially as herein
shown and described and for the purpose set forth.
5th. In a type writing machine, the combination with the key levers A of the
staples B, discs L, the string or wire J, and a transverse rail D, substantially as
herein shown and described and for the purpose set forth.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Twenty eighth day of March, A.D. 1881.
A. M. CLARK. (L.S.)