Improvements in Type-writing Machines.
Year: 1899

page_text: Date of Application, 6th Mar., 1899-Accepted, 6th May, 1899
COMPLETE SPECIFICATION.
Improvements in Type-writing Machines.
1, BURNHAM Coos STICKNEY, of No. 151, Jefferson Avenue, in the City of
Elizabeth, County of Union and State of New Jersey, in the United States of
America, Inventor, 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 the platens of type-writing machines, and its object is
to prevent the repeated hammering action of the types from indenting or corrugat-
ing the surface of the platen, and also to provide the platen with an improved
cover or printing surface.
After short use a platen presents a series of indentations, which make it im-
possible to obtain perfect impressions of the types upon the paper. They are caused
by the repeated hammering of the types in the same places; the sharp types, such
as the period and comma, making the deepest impressions. The indentations
extend in lines lengthwise of the platen, at intervals corresponding to the teeth
in the letter-spacing rack, and the lines extend around the platen at intervals
corresponding to the teeth in the line-space wheel.
My invention consists in combining with a platen means for progressively
subjecting the entire circumference thereof to the hammering action of the types,
whereby the smoothness and evenness of its surface will be preserved; in combining
with a platen means for turning it through an aliquant part of a complete revolu-
tion at each line-spacing operation; in combining with a platen and a line-space
wheel means for rotating the platen relatively to the line-space wheel; in com-
bining with a platen and a line-space wheel provided with evenly spaced teeth
means for turning the platen an aliquant part of a complete revolution at each
line-spacing operation; in combining with the platen means for progressively
subjecting the printing-surface thereof to the impact of the types throughout its
length; in combining with a platen means for progressively giving it slight length-
wise movements independently of the letter-spacing movements; in providing means
for regulating the density of the platen cover.or printing surface; and it further
consists in the various features of construction and combinations of devices herein-
after more fully described and particularly pointed out in the appended claims.
In the accompanying, drawings,
Fig. 1 is a plan of so much of a type-writer carriage as is necessary to show my
invention;
Fig. 2 is a sectional plan of the platen;
Fig. 3 is a plan of the platen shaft and attached devices, the platen having
been removed;
Fig. 4 is another plan of the platen shaft, the ratchet-wheel having also been.
romoted.

page_text: rigs. 7 and 8 are respectively end and plan views of the line-space wheel and
attached devices;
rig. 9 is an end view of the scroll;
Fig. 10 is an end view of Fig. 1;
Fig. 11 shows plan and elevation of the worm;
Fig. 12 is a sectional front elevation of the line-space wheel and scroll, showing
the manner in which the worm is caused to revolve on its own axis by the scroll
during the rotation of the line-space wheel;
Fig. 13 is a front elevation of Fig. 1; and
Fig. 14 is a perspective view of one of the washers that constitute, the printing
surface of the platen.
In the various views the same numeral of reference will be found to designate
the same part.
1, 2, 3 and 4 are respectively the front, back and end bars of the platen frame,
which may be hinged to the guide-rail 5 in. the usual manner. 6 is the usual
letter-spacing rack. The carriage may be supported in front by the usual rail,
on which may run the roll shown attached to the front bar 1, and may be propelled
by a spring or other means. 7 is the platen, 8 the line-space wheel, provided with
evenly spaced teeth. 9 is the line-spacing pawl, and,-10 the line-spacing lever,
which after actuation are restored to normal position by spring 11. 12 is the
check-spring, provided with an anti-friction roll 13 and engaging the line-space
wheel to prevent accidental rotation thereof.
METHOD OF SUBJECTING THE ENTIRE CIRCUMFERENCE OF THE PLATEN TO THE
IMPACT OF THE TYPES.
I have so organized the machine that the line-space movements of the
platen do not match the teeth of the line-space wheel; that is to say, while the teeth
of the line-space wheel are evenly spaced, so that each tooth occupies an aliquot
part of the periphery of the wheel, the platen at each line-space operation is rotated
through an aliquant part of a complete revolution. Consequently the blows of
the types do not fall upon exactly the same spot at successive revolutions of the
platen, so that instead of deepening the impressions left by preceding types, they
tend rather to obliterate such former impressions. The entire circumference of
the platen is thus progressively subjected to the action of the types. I have devised
a variety of means for carrying out this portion of my invention, and will now
describe the preferred construction.
To the line-space wheel 8 is secured a bracket 15, in which is mounted a screw
or worm 14 (Figs. 7, 8), which is provided with a head 16, which has a series of
flat pins 17 (shown clearly at Fig. 11), by which the worm is actuated, as will
presently be explained.
To the platen shaft 18 is rigidly secured a worm-wheel 19 (Fig. 4), which is pro-
vided with a hub that fits the shaft and is secured thereto by the set-screw 21.
This hub also fits inside the hub 22 of the line-space wheel 8. At Figs. 3 and 5
the parts just described are shown assembled, the worm 14 meshing with the worm-
wheel 19. The platen-shaft may be rotated independently of the line-space wheel,
by the actuation of the worm 14. To prevent lateral motion of the line-space
wheel, the hub 20 is provided with an annular peripheral groove 23, and the hub 22
is provided with an inwardly projecting screw 24, which enters the groove.
the screw 14 locks the worm-wheel and shaft against independent rotation, the
rotary motion of the line-space wheel at the line-spacing operation will be trans-
mitted to the platen-shaft and platen.
As
To rotate the worm about its own axis, the teeth 17 are arranged in engagement
with the stationary scroll 25 (Fig. 12). These teeth are twisted or set diagonally
into the head 16, so as to match the grooves in the scroll at the point of their
engagement therewith. During the rotation of the-line-space wheel the worm 14

page_text: is carried bodily around, and its teeth 17 follow the evolute grooves of the stationary
scroll, which causes the worm to turn on its own axis. During six revolutions
of the line-space wheel the worm will make one revolution on its own axis, as
there are six of the teeth 17. Hence during six revolutions of the line-space wheel
the relative positions of the line-space wheel and worm-wheel 19 will be altered
to the extent of one tooth of the latter; and there is of course the same relative
change in the positions of the platen-shaft and platen as compared with the line-
space wheel. Assuming that there are 50 teeth in the worm-wheel, the platen will
make six and one-fiftieth revolutions while the line-space wheel is making six,
During one revolution of the latter, the platen makes one and one-three-hundredth
revolutions; and during 300 revolutions of the line-space wheel the platen makes..
301 revolutions. Assuming the circumference of the platen to be six inches, and
that the line-space wheel has 32 teeth, it will be seen that at every 33d line the
writing will fall upon the platen at a point one-fiftieth of an inch in advance.
The line-space distance or interval will be three hundred and one sixteen-
hundredths of an inch, which of course is an aliquant part of six inches, the entire
circumference. At each line-space movement the platen will revolve through
eleven and twenty-three eightieth's degrees, which is an aliquant part of a complete
revolution of 360 degrees.
If desired, the platen may be made to revolve more slowly than the line-space
wheel by making the scroll threads involute instead of evolute, or by reversing the
threads of the worm gear.
I provide a friction device between the platen and the line-space wheel, the
resistance of which must be overcome when the platen is rotated independently.
of the latter. The object thereof is to prevent the accidental independent motion
of the platen, which might occur by reason of loose fit or wear of the parts, and
which would cause a wavy and irregular appearance of the lines of writing. The
friction device consists of a split washer 26, which fits over the hub 20, and is
arranged to expand against the inner side of the worm-wheel 19 and the outer edge
of the hub 22 (Figs. 1.3). By this means the frictional opposition to the indepen-
dent rotation or shake of the platen may be rendered as great as or greater than
the resistance offered by the check-spring 12 to the rotation of the line-space
wheel, thus effectually preventing erratic movements of the platen.
LENGTHWISE PLATEN MOTION.
The previously described devices will serve to considerably prolong the life
of the platen; but I prefer to also employ means for, subjecting the platen. pro-
gressively lengthwise to the hammering action of the types, thus increasing the
tendency of the blows to obliterate preceding impressions and also avoiding the
liability of circumferential grooves being cut in the platen by the sharper types.
I provide the platen at its right-hand end with a hub 27, in the periphery of
which is cut a cam groove 28 (Figs. 1, 2). To the line-space wheel '8 is fixed.a
bracket 29, from which projects a pin 30, that engages the cam groove. The pin
traverses the groove during the independent motion of the platen relatively to the
line-space wheel, thus causing the platen to reciprocate endwise slowly, the extent
of such motion being about one-tenth of an inch. The groove is shaped so that
during one independent revolution the platen moves endwise twice in each direction.
It may, however, be caused to move three times, or only once, by changing the
shape of the cam groove. At Fig. 1 the platen is shown in full lines at the
extreme left-hand end of its lengthwise movement, and in dotted lines at the
extreme right-hand end.
During the line-spacing operation the whole system will appear to revolve
together as one piece around the axis of the platen, as the independent motions of
the platen relatively to the line-space wheel are so gradual as to be imperceptible.
To cause the platen to rotate with the shaft, the latter is provided at its left.
and end with a cross-arm 31, from which project inwardly pins 32, parallel with
the shaft (Figs. 3, 6). The platen is provided with holes 33, which receive the

page_text: free ends of the pins 32. The pins transmit the motion of the shaft to the platen,
and are sufficiently long to permit the latter to move independently endwise the
required distance. To minimize the possibility of shake or lost motion between
the platen and shaft, the pins 32 are placed as near as possible to the periphery
of the platen.
The nipple 36 formed upon the right-hand end of the platen-shaft fits into a
hole in the end bar 4. A hole in the other end of the shaft receives the end of
a screw 38 secured in the end bar 3. The shaft is thus easily removed from the
carriage.
IMPROVED PLATEN CONSTRUCTION.
The required density of rubber platen-covers is obtained by mixing with the
pure rubber, which is too soft to form a suitable printing surface, a suitable
quantity of various mineral substances. Platens or platen covers made from
such composition begin at once to harden, and in a short time become unfit for
use for making single copies, as when the platen is too hard the outlines of the
letters do not show clearly. I have provided means for obtaining the required
density of the platen or printing-surface by compression, and am enabled thereby
to employ other substances, such as leather or felt, which will not harden with
age, and the density of which may be increased or decreased to the proper degree.
A series of washers 40, preferably leather, are placed side by side upon a wooden
core 39, a sufficient number being used to extend beyond the ends of the core.
The end plates or discs 34, 35 are then secured to the core by screws 41, thus com-
pressing the washers. If desired, the washers may be submitted to pressure before
being placed in position, to increase their density. If the platen is found to be
too soft, one end plate may be removed and one or more washers added; then
the plate may be replaced and screwed into its former position, compressing all the
washers and making them harder. If the platen is found to be too hard, the screws
may be turned a little so as to diminish the compression, or one of the washers may
he removed, allowing the others to expand and soften.
No rubber composition of which I am aware will serve equally well for single
copies and heavy manifolding. Leather, however, may be compressed until it is
hard enough to serve excellently for manifolding purposes, and at the same time
it will be unsurpassed for making single copies, because it has a low degree of
elasticity and therefore brings out sharply the complete outlines of the types upon
the paper. In consequence of its comparative inelasticity, however, the types
will penetrate its surface more readily than that of the usual rubber composition:
but this will not prove an objection when the entire printing surface is subjected
uniformly to the action of the types, as in the manner above described.
So far as both the broad and minor features of my invention are concerned,
many changes in form and detail construction and arrangement may be made
without departing from the spirit of my invention, and it is not my intention to
limit myself in any instance to the precise details above described.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. In a type-writing machine, as a means for securing even wear of the platen.
the combination with a platen of automatically operating means for slightly vary-
ing the position thereof relatively to the printing point, substantially as set forth.
2. In a type-writing machine, the combination with a platen of automatically
operating means for progressively causing slight variations in the position thereof
relatively to the printing point, substantially as set forth.
3. In a type-writing machine, the combination with a cylindrical platen of
means for progressively subjecting the entire circumference thereof to the action
of the types, substantially as set forth,

page_text: 4. In a type-writing machine, the combination with a cylindrical platen and
a reciprocatory driver therefor, such as a line-space lever, of means actuated by the
lever for progressively subjecting the entire circumference of the platen to the
action of the types, substantially as set forth.
5. In a type-writing machine, the combination with a cylindrical platen and its
line-space lever of means for turning the platen through an aliquant part of a
complete revolution at each actuation of the line-space lever, substantially as set
forth.
6. In a type-writing machine, the combination with a cylindrical platen and
a line-space wheel provided with evenly spaced teeth of means for turning the
line-space wheel through an aliquot part of a complete revolution and simul-
taneously turning the platen through an aliquant part of a complete revolution,
substant'ally as set forth.
7. In a tyre-writing machine the combination with a cylindrical platen and a
line-space wheel connected thereto of automatically operating means for slightly..
rotating the platen relatively to the line-space wheel, substantially as set forth.
8. In a type-writing machine, the combination with a cylindrical platen and
a line-space wheel connected thereto of automatically operating means for pro-
gressively rotating the platen relatively to the line-space wheel, substantially as
set forth.
9. In a type-writing machine, the combination with a cylindrical platen and
a line-space wheel connected thereto of means for progressively rotating the platen
relatively to the line-space wheel during the rotation of the latter, substantially
as set forth.
10. In a type-writing machine, the combination with a cylindrical platen and
a line-space wheel connected thereto and rotating simultaneously therewith, of
automatically operating means arranged between the wheel and the platen for
progressively rotating the platen relatively to the wheel, substantially as set forth.
11. In a type-writing machine, the combination with a cylindrical platen and
aline-space wheel connected thereto and rotating simultaneously therewith, of
a screw device arranged between the platen and the line-space wheel and serving
to transmit the motion of the line-space wheel to the platen, and also adapted to
cause alterations in the relative positions of platen and line-space wheel, sub-
stantially as set forth.
12. In a type-writing machine, the combination with a cylindrical platen, a
linc-space wheel, and means arranged between them for automatically varying
their relative positions, of a friction device also arranged between the platen and
line-space wheel and serving to oppose the independent rotation of the former
relatively to the latter, substantially as set forth.
13. In a type-writing machine, the combination with a cylindrical platen pro-
vided with a worm-wheel of a line-space wheel provided with a worm to mesh
therewith, and means for actuating the worm to rotate the worm-wheel and platen.
relatively to the line-space wheel, substantially as set forth.
14. In a type-writing machine, the combination of a platen-frame provided with
a threaded device, such as a scroll, a line-space wheel provided with a worm having
a series of teeth to engage the scroll, and a platen provided with a worm-wheel
to engage the worm, substantially as set forth.
15. In a type-writing machine, the combination with a platen of automatically
operating means for progressively subjecting the printing surface thereof to the
action of the types throughout its length, substantially, as set forth.
16. In a type-writing machine, the combination of a platen, a carr age or
frame therefor, and automatically. operating. means for progressively moving the
platen lengthwise independently of the carriage or frame, substantially as set
forth.
17. In a type-writing machine, the combination of a platen, a carriage or framie
therefor, and automatically operating means for progressively reciprocating the

page_text: platen lengthwise independently of the carriage or frame, substantially as set
forth.
18. In a type-writing machine, the combination with a platen arranged to move
lengthwise for letter-spacing and to revolve for line-spacing, of means for auto-
matically moving the platen gradually endwise during successive revolutions
thereof, substantially as set forth.
19. In a type-writing machine, the combination with a cylindrical platen of
means for progressively subjecting the entire printing surface thereof both length-
wise and circumferentially to the action of the types, substantially as set forth.
20. In a type-writing machine the combination with a platen and a laterally
inactive line-space wheel connected thereto of means for gradually rotating and
moving the platen endwise relatively to said wheel, substantially as set forth.
21. In a type-writing machine, the combination with a platen provided with
a cam of a relatively fixed pin arranged in engagement with the cam, to cause
the platen to move endwise when rotated relatively to the pin, substantially as
set forth.
22. In a type-writing machine, the combination with a platen and a laterally
inactive line-space wheel of a cam device arranged between the platen and the
line-space wheel, and operating, to reciprocate the platen endwise when the latter
is rotated independently of the line-space wheel, substantially as set forth.
23. In a type-writing machine the combination with a platen provided with a
cam groove of a laterally inactive line-space wheel provided with a pin for engaging
the cam groove, and means for rotating the platen relatively to the line-space
wheel, substantially as set forth.
24. In a type-writing machine, the combination with a frame of a shaft mounted
therein, a platen having an automatic reciprocating movement upon the shaft,
means for rotating the shaft, and means for causing the platen to revolve with
the shaft, substantially as set forth.
25. In a type-writing machine, the combination of a platen having a limited
automatic reciprocating movement and provided with one or more openings 33,
and a shaft provided with an arm or arms 31 and pins 32 to enter the openings,
substantially as set forth.
26. In a type-writing machine, the combination of a shaft, means for rotating
it, a platen arranged to automatically reciprocate upon the shaft, and means fixed
to the shaft and connected to the platen at a point near its periphery to cause the
platen to revolve with the shaft, substantially as set forth.
27. In a type-writing machine, the combination of a platen-frame provided
with a threaded device, such as a scroll; a line-space wheel provided with a worm
having a series of teeth to engage the scroll, and provided also with a pin, as 30,
said line-space wheel being held against lateral motion; a shaft mounted in the
frame and provided with a worm-wheel for engaging the worm; and a platen
mounted upon the shaft and adapted to slide thereon but to revolve therewith,
and provided with a cam-groove to engage the said pin, substantially as set forth.
28. In a type-writing machine, the combination with a rigid cylindrical platen
or platen cover of means connected thereto for regulating the density thereof by
compression or expansion, substantially as set forth.
29. In a type-writing machine, the combination with a series of washers set
side by side to form a rigid cylindrical printing surface or platen, of means for
compressing the washers, substantially as set forth.
30. As a new article of manufacture, a rigid cylindrical platen or platen cover
for type-writing machines composed of a series of compressed leather washers,
substantially as set forth.
31. In a type-writing machine, a cylindrical platen comprising a core or frame
provided with end plates and a series of washers arranged between the plates and
compressed thereby, substantially as set forth.
32. In a type-writing machine, the combination with a cylindrical platen or

page_text: platen cover constructed from compressed leather of means for progressively sub-
jecting the entire printing surface thereof to the action of the types, substan-
tially as set forth.
Dotod this 21st day of Wahmo 1000
FELL & JAMES;
Agents for the Applicant.