Improvements in Type-writing Machines.
Year: 1890

page_text: Date of Application, 25th Nov., 1890
Complete Specification Left, 25th Aug., 1891-Accepted, 3rd Oct., 1891
PROVISIONAL SPECIFICATION.
Improvements in Type-writing Machines.
I, DAVID BLYTH ADAMSON, of 80 Hartington Road, Liverpool, in the County
of Lancaster, Manufacturer, do hereby declare the nature of this invention to be
as follows
-
This invention relates to type-writing machines of the kind set forth in the
Provisional Specification of my prior application for Letters Patent, dated
21st July 1890, and numbered 11349.
the two.
In such type-writing machines the type are fixed to a flexible type strip, one
end of which is attached to a light spring return drum, and the other end to a
segmental circular rim, the type strip passing over an impression roller between
When the key lever of any character is depressed, the appropriate type
is first drawn to the top of the impression roller and the impression is then made.
My present invention has reference to improvements in the method of mounting
and operating the type strip, to a device for arresting the motion of the type
drum immediately before the printing is effected, and to improvements in the
impression and paper carriage feeding mechanisms.
According to my present invention, I dispense with the light spring return drum
to which one end of the type strip is attached and I attach both ends of the type
strip to the segmental circular rim which now becomes, preferably, a circular drum,
and is journalled on the type frame. The type strip is led from the said drum,
between the sides of the type frame, over an impression bar and one or more
leading pulleys, and finally back to the drum, after the manner of an endless belt.
The device for arresting the-motion of the type drum just before printing is as
follows:-
provide a light lever, pivotted to the type frame, the lower end of which
carries a brake block of rubber or other suitable material which, when the lever is
operated, has a frictional grip on the inside of the rim of the type drum; the
lever is so balanced that normally the brake is clear of the drum.
The brake lever is operated by a tripper on the carriage feed lever which, in
passing, engages with a spring pawl on the brake lever; the contact is but
momentary and occurs just prior to the impression, so that if the drum has to
rotate an additional small amount before the impression takes place, it is free to
do so.
In my prior Provisional Specification aforesaid, the arrangement described for
effecting the printing consists of a device for swinging the type frame through a
small angle, so that the impression roller carried thereon is raised till the type
immediately over it comes into contact with the paper; according to my present
invention, the type frame is incapable of vertical movement and the printing is
effected by slightly raising an impression bar placed below the type strip at the
printing point.
This impression bar is carried on a lever pivotted on the type frame and is
raised by deflecting the lever through a small angle; the arrangement for deflecting
the lever is similar to that already described in my prior Provisional Specification
aforesaid for swinging the type frame, except that I prefer to use a weight in
place of the impression spring and to dispense with the return spring, using in
place thereof, a projection on the feed lever frame, adapted, on the ascent of the
latter, to bear under and return the impression lever to normal position.
I also fit on the lever which carries the impression bar, a pin which, just prior to
printing, bears against the lower free length of the type strip and draws it taut.

page_text: In order to secure exact register in printing I prefer to fix one or more short
conical pegs on the top of the impression bar, which engage with corresponding
holes in the type strip when the impression bar is raised at the instant of
printing.
the
The paper carriage feeding, mechanism consists of a toothed rack attached to
carriage and a feed pawl carried on a lever, operated by the feed lever frame,
and also independently by a finger plate or bar. The feed rack and pawl are of
ordinary construction except that the latter has an inclined or wedge shaped
portion which, at the end of its throw, bears under a fixed pin, thus locking the
pawl firmly into gear with the rack and holding the carriage firmly during
printing.
In order to prevent the possibility of several impressions being inadvertently
superposed at the end of a line, I fit a projection on the paper carriage which
immediately the last impression of the line has been made, rides over a fixed
abutment and so lifts the carriage clear of the type.
Dated this 24th day of November 1890.
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Type-writing Machines.
I, DAVID BLYTH ADAMSON of 80 Hartington Road Liverpool, in the County
of Lancaster, 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 :-
This invention relates to type writing machines of the kind set forth in the
Complete Specification of my prior Letters Patent dated 21st July, 1890 and
numbered 11349.
In such type writing machines, the type are fixed to a flexible type strip, one
end of which is attached to a light spring return drum and the other end to a
segmental circular rim, the type strip passing over an impression roller between
the two. When the key lever of any character is depressed, the appropriate type
is first drawn to the top of the impression roller and the impression is then made.
My present invention has reference to improvements in the method of mounting
and operating the type strip, to a device for arresting the motion of the type drum
immediately before the printing is effected, and to improvements in the impression
and paper carriage feeding mechanisms.
The accompanying drawings show a type writing machine constructed generally
in accordance with my prior Specification aforesaid but with my present
improvements incorporated.
Fig. is a front elevation, Fig. I is a plan, Fig. III is a side elevation,
Fig. IV is a side elevation in section on the line A A of Fig. II, Fig. V is a part
plan, Fig. VI is a view similar to Fig. IV but showing one of the key levers
depressed, Figs. VII and IX are elevations of the type frame from opposite
sides, Fig. VIII is a plan of same, Fig. X is a sectional elevation on the line B B
of Fig. IX, Fig. XI shows the device for lifting the paper carriage at the end of
the line and Fig. XII shows the clasp for attaching the type strip to the drum.
Throughout the drawings, the same parts are indicated by the same reference
figures and as far as possible the drawings are figured similarly to those of my
prior Specification aforesaid although many of the parts which are common to both
are not herein referred to; in the case of sections, the direction in which they are
viewed is indicated by the small arrows placed adjacent to the letters denoting the
plane of section.
According to my present invention, I dispense with the light spring return drum

page_text: to which one end of the type strip is attached, as described in my prior Specification
aforesaid, and I attach both ends of the type strip 10 to the drum 11 secured to
the spindle 111 journalled on the type frame. The strip 10 is led from the drum 11,
between the sides of the type frame. over the leading pulleys 12 and 13 and the
impression bar 44, and finally back to the drum 11, after the manner of an endless
belt; the clasps by which the attachment is made being shown in Fig. XII.
The type strip is operated in a manner resembling that described in my prior
Specification aforesaid, that is to say, the pinion 40 secured to the spindle 111
gears with the spur segment 39 fixed to the lever frame 38 extending below all the-
key levers and depressed by each; it will be seen, however, that in the present
arrangement, the type strip is driven in both directions by the spur segment 39.
The device for arresting the motion of the type drum 11 just before printing is
shown in Figs. III, VII and VIII.
62 is a light lever, pivotted at 61 to the type frame and carrying the brake
block 60 of rubber or other suitable material which, when the lever is operated,
has a frictional grip on the inside of the rim of the type drum 11; the lever 62 is
balanced by the weight 63 so that normally the brake is clear of the drum. The
brake lever is operated by the tripper 54, carried on an arm of the pawl lever 35,
which, in passing, engages with the pawl 64 pivotted to the lever 62; the motion
of 64 relative to 62 is limited by the stop 65 which allows the tripper 54 to return
without operating the brake lever. The contact between the brake and the type
drum is but momentary and occurs just prior to the impression, so that if the
drum has to rotate an additional small amount it is free to do so.
In my prior Specification aforesaid the arrangement described for effecting the
printing consists of a device for swinging the type frame through a small angle so
that the impression roller carried thereon is raised till the type immediately over
it comes into contact with the paper; according to my present invention the type
frame is incapable of vertical movement and the printing is effected by slightly
raising the impression bar 44 which is carried on the lever 45 pivotted at 47 to
the type frame. The arrangement for operating the lever 45 in order to raise the
impression bar resembles that already described in my prior Specification afore-
said for swinging the type frame. That is to say,-41 is an impression lever
carrying a pawl 42 adapted to engage in passing with the pin 43 carried by the
lever 45; the lever 41 is urged forward by the weight 41' but held back by the
holding pawl 46. When a key is depressed and just as it reaches its lowest
position, the depending arm 301 (Fig VI) of the lever 30, which is fulcrumed
at 28' and linked to the spacing frame 28 by the connecting link 30', bears upon
the adjustable screw 49, disengaging the holding pawl 46 from the lever 41 so that
the latter springs forward as shown in Fig. VI, deflects the pin 43 and lever 45
and raises the impression bar as shown in dotted lines in Fig. IX; by the same
movement the pin 15 bears as shown in dotted lines against the lower free length
of the type strip and draws it taut; on the ascent of the key lever, the pin 56 on
the lever 30 bears under the projecting piece 57 on the impression lever and returns
the latter to normal position. It will be seen that the present arrangement differs
from that set forth in my prior Specification aforesaid inasmuch as the impression
spring and the return spring are dispensed with, the place of the former being
taken by the weight 41' and that of the latter by the pin 56. The mass of the
weight 41 causes a minute time interval between the descent of the key lever and
the impression, which is of advantage as it allows the paper carriage to complete
its spacing movement before the impression occurs.
In order to secure exact register in printing I fix a short conical peg 16 on the
top of the impression bar 44, which engages with corresponding holes in the type
strip when the impression bar is raised at the instant of printing. If the type
have a metallic or hard backing the said holes are made in the latter; if the
material is not sufficiently strong and wear-resisting, the holes may be strengthened
by small eyelets.
The paper carriage feeding mechanism consists of a toothed rack 32 attachel to

page_text: the carriage and a feed pawl 31 carried on the pawl lever 35 operated by the feed
lever frame 28 and also independently by the finger plate or bar 36,
The feed rack and pawl are of ordinary construction except that according to
my present invention the feed pawl has an inclined portion which at the end of its
throw bears under the fixed pin 58 carried on the arm 59 of the bracket 52, thus
locking the pawl firmly into gear with the rack and holding the carriage firmly
during printing: 51 is a fixed pin for steadying the pawl lever.
In order to prevent the possibility of several impressions being inadvertently
superposed at the end of a line, I fit a projecting piece 75 on the paper carriage
(see Fig XI) which immediately the last impression of the line has been made,
rides over the fixed abutment 76 and so lifts the carriage clear of the type.
It is to be understood that I make no claim herein to any of the subject matter
of my prior Letters Patent aforesaid which has been introduced herein in order to
illustrate the application of my present improvements.
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
In type writing machines such as are herein described,-
1. Attaching both ends of the type strip, to a type drum, the angular motion
of which, on the depression of any key lever, draws the appropriate type to the
top of an impression bar over which the type strip passes after the manner of
an endless belt, substantially as described and illustrated.
2. The use of the pin 56 for returning the impression lever to normal position,
substantially as described and illustrated.
3. The device for arresting the motion of the type drum which consists of a
brake and mechanism whereby the movement which effects the spacing operates
the said brake bringing it into momentary contact with the type drum, substar-
tially as described and illustrated.
4. The device for holding the paper carriage stationary during printing which
consists of a pin rigidly attached to the framework of the machine and adapted
to lock the feed pawl, at the end of its stroke, into gear with the feed rack,
substantially as described and illustrated.
5. The device for preventing the accidental superposition of several impressions
at the end of a line, which consists of a projecting piece on the paper carriage
which, when the last impression is made, rides over a fixed abutment and lifts the
carriage clear of the type, substantially as described and illustrated.
6. The device for exactly locating the type prior to the impression which
consists of a pin on the impression bar adapted to engage with holes in the type
strip the latter being pulled tant by a pin attached to the lever operating the
impression bar, substantially as described and illustrated.
7. The combination and arrangement of parts forming the improved type writing
Imachine, substantially as described and illustrated.
Dated this 24th day of August 1801
SLOAN & LLOYD BARNES,
Castle Chambers, Castle Street, Liverpool, Agents for the Applicant.