Year: 1896

page_text: EDWARD WILLIAM HEARN 17 Nassington Road Hampstead N.W. Electrical
Engineer do hereby declare the nature of this invention to be as follows:-
This invention has reference to improvements in type writing machines and deals
more particularly with the motion communicated to the type wheel by which much
adjustment is dispensed with and a simple combination of parts produced.
The several parts of the machine consist of the following:-

page_text: working in the slot of the guide wheel, rising arrests the type arm, 3, attached to
the type spindle. By the same operation the printing hammer is thrown by the
action of the hammer lever against the face of the type wheel.
The action of the hammer lever also causes the carriage lever, 9, to be drawn
down. The pawl attached thereto pulls the ratchet wheel, 10, gearing with the
carriage rack. Each depression of the carriage lever pulling the wheel one
tooth.
Over motion of these wheels 10 is prevented by causing the carriage lever to
press against a stop which bites into the teeth of the ratchet wheel as will be easily
understood.
By driving the type spindle by means of a spring kept at tension it will be seen
that the key levers may all descend the same distance and no differential adjustment
is necessary in them.
On the return of the hammer lever to its normal position the winding lever is
pushed back to its normal position by the greater power of the spring which retracts.
the said hammer lever..
I may, in order to obtain a more positive result in the event of any hesitation
on the part of the winding lever to act quickly enough connect the winding lever
with the hammer lever by a light spring as well.
It should be clearly understood that the pin attached to the winding lever and
in contact with the hammer lever rests on the upper part of the hammer lever so
that there is no strain or locking on this lever as there otherwise would be when
the controlling type arm, 3, come in contact with the key lever.
The spacing lever, 8, operates the carriage lever in the same way as the hammer
lever hereinbefore described with the same result.
The face of the type wheel is inked by means of two felt rollers suitably
pivotted.
If necessary I may use a second hammer lever working in contact with the
hammer lever described in 7. The action of this second lever being to throw the
printing hammer back and on release cause it to be thrown against the face of
the type wheel. Thus getting an automatic stroke of the printing lever. To
prevent it remaining in contact with the type wheel a rebounding action would be
given to it by causing it to strike against a light spring.
It should be stated that all the levers are retracted by springs suitably fixed.
The paper carriage slides in a grooved bed the paper passing between two friction
rollers into a tube.
The said rollers being held together by springs.
In order to simplyfy the construction of the machine I may make the fulcrum of
the key levers a plain ring on which they would be mounted. In this case the
key levers would be notched at a suitable angle at that part where they rested on
the ring. While to prevent them shifting the part immediately above would have
vertical projections. These projections would be fitted into a stamped plate which
would also form the index plate of the machine. The said plate having slots
stamped on its inside edge and corresponding to the number of keys in the
machine.
As a modification of the winding mechanism I may connect the hammer lever
with the winding lever by a spring, as herein before explained and retract the
winding lever by a spring, in which case tension on the latter spring would be
caused by the descent of the hammer lever.
Dated this 20th day of January 1896.

page_text: cause the frame lever R to move upwards, this action will depress the driving
lever N at the end where it is attached to the lever K by the spring M. This
spring pulling on the lever K will cause it by the strap 1 attached thereto to draw
the segmental wheel H by which the type wheel will be caused to rotate. At the
same time the pawl Z will have thrown the hammer wheel Y a tooth forward, but
on releasing the key lever the pawl Z holding the wheel Y rigidly will throw the
hammer U forward to make the necessary impression and when the frame lever R.
returns to its normal position the pawl will have passed out of gear with the
wheel.
On the driving lever N striking the pin g the lever K will also be returned to
its normal position.
In order that the type wheel should be stationary while an impression is being
made, it should be explained that the depresion of the driving lever N at that
point where it operates the pin g is so regulated that it passes out of contact with
the pin and the hammer is caused to act just before the driving lever again comes.
in contact with the pin g to return the lever K to its normal position.
By thus throwing the difference on the spring M I am enabled to dispense with
a differential depression of the key levers or the necessity of graduating or stepping
the circular arm which is operated by them. As the key levers T come in the path.
of the type arm F at that point where they lift the circular arm S, the contact is
rigid; and if the the driving lever N were connected by a rigid arm to the lever K.
it would necessitate the graduating or adjustment of the keys or the circular arm.
before referred to.
The spacing mechanism is obtained by pivotting two wheels h. i on a support j.
The front wheel h gearing with a rack k hinged to the paper carriage frame l
at m. The ratchet wheel i being operated by a push pawl n controlled by a
spring. The lever o Fig. 5 which carries the pawl n being operated by the set-
screw p attached to the frame lever R.
To prevent any overmotion of the wheel ha pin 9 is caused to gear or lock it on
the lever o rising, and by this means imparting a step by step motion to the paper-
carriage.
The pawl is loosely mounted on the lever o and in its normal position rests
against a tooth of the ratchet wheel i to keep the carriage stationary. As the
lever o rises the pawl r frees itself of the ratchet wheel i. A spring serves to
return the lever o to its normal position.
The plate t represents the "spacer" and is attached to a lever u pivotted at v..
This lever u operates the lever o as shown in Fig. 5 by the curved head w.
The paper is held to the roller 18 by a curved spring a fixed to the frame of the
paper carriage at y; and to facilitate the insertion of the paper a segmental tube z
is hinged to the frame of the paper carriage at 2. I may if desirable hinge this.
segmental tube to the curved spring a.
Fig. 8 shows an alternative device for imparting motion to the type wheel. In
this case the spring 3 in its normal position is always kept at tension by the.
superior power of the spring operating the driving lever N. On the said lever
descending it will be seen that the lever K must follow by the contraction of the
spring 3.
The frame lever R is operated by a spring 4. To this spring tension may be given
by turning the nut 5; this will also cause the hammer to strike harder when it is
desired to manifold.
The different rows of type are brought into the printing plane by the lifter 7
which is pivotted on a support 25. On pressing the key for "caps." 8 or "figs." 9.
the type wheel will be raised as desired and in order to lock down the said lifter
notches are cut at 10 & 11 into which a sharp edged lever 12 fits.
A shield 13 common to wheel machines is shown in Fig. 1, and part of the
cover 30 of the machine on which the characters are placed in Fig. 3.
The inking of the type wheel is effected by a felt roller 27 mounted on a
support 14 Fig. 7, the support being pivotted to a pin 15 fixed to a bracket 16 as.