Improvements in mechanical Time-indicators.
Year: 1897

page_text: Improvements in mechanical Time-indicators.
I, SAMUEL POWERS THRASHER, of New Haven, Connecticut, United States of
America, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to mechanical time-indicators or time-pieces in which the
hours and minutes are indicated by numerals visible through an opening or open-
ings in the face or front of the casing of the apparatus, the said numerals being
changed at the proper times by the turning of one or more of a series of wheels
or drums.
I find it advantageous to employ three of these wheels or drums mounted upon
a common axis, one for indicating units of minutes, another for indicating tens
of minutes and the third for indicating the hours; and to mark the numerals for
indicating the time of day either upon the said wheels or drums themselves, or
upon endless bands or ribbons passing over the said wheels or drums.
I provide suitable mechanism whereby power will be constantly applied to the
said wheels or drums for the purpose of turning the same; and electrical or other
devices whereby the said wheels or drums will be restrained from rotation and
will be released at intervals to permit the required step-by-step rotation thereof.
Another feature of my present invention is an improved construction of the
apparatus whereby I am enabled to advantageously employ endless bands or ribbons
passing over the said wheels or drums and having marked thereon the numerals
for indicating the hours and minutes. By employing endless bands or ribbons in
this manner, large figures can be used for indicating the time of day without the
employment of large drums. This arrangement is therefore very advantageous
for use on towers or other places where the time has to be shown so that it can be
read at a long distance.
My said invention also comprises other improvements hereinafter mentioned.
In carrying my said invention into practice, I employ, in combination with each
of the aforesaid wheels or drums, mechanism similar to a clock-movement whereby
power is constantly applied to the said drum so as to turn it about its axis whenever
it is free, the trains of wheels being varied according to the periods of revolution
of the drums respectively. When the numerals are marked upon the drums them-
selves, I provide the minute-drums with stop-fingers and trip-fingers adapted to
engage with stop-pawls and trip-levers respectively, in the operations of stopping
and releasing the drums. The said stop-pawls and trip-levers are mounted on
independent shafts, there being a stop-pawl and shaft for each drum, and the shafts
for the tens-drum and hour-drum being provided with trip-levers whereby the said
trip-fingers will be caused to release the said drums from their stop-pawls.
I sometimes provide an electrical device for releasing the units-drum at the
proper times, which device comprises a rod or link coupled at its upper end to the
stop-pawl of the units-drum and provided at its lower end with an adjustable collar
or nut. The said device also comprises an electro-magnet having an armature
017

page_text: attached to a pivoted lever which is movable between two stops, and which has a
spring arm or extension provided at its free end with a perforated or slotted head
or hammer, through which extends the said rod or link, the said head or hammer,
in its normal position, resting a short distance above the collar or nut on the said
rod or link. When the magnet is energized by the completion of the electric
circuit by a master time-movement or clock, it draws the armature-lever up against
the upper stop, and on the electric circuit being interrupted, the said armature-
lever drops onto the lower stop, and, by reason of the flexibility of the spring
extension of the said lever, the said head or hammer falls so far below its normal
position as to strike the said collar or nut and momentarily disengage the stop-
pawl from the units-drum, the said head or hammer immediately rising to its
normal position, and the said pawl engaging with the next stop-finger on the
said drum when the latter has been rotated one step.
When I employ endless bands or ribbons with the numerals marked thereon,
I arrange each of the said bands or ribbons upon an upper and a lower wheel or
drum, and provide sets of mechanism or clockwork whereby power is constantly
applied to the upper drums respectively, the lower. drums being used simply to
keep the bands or ribbons taut. I combine, with the said upper drums and the
bands, stop-pawls mounted on independent shafts and adapted to engage with
projections on the said drums respectively, and I mount on the shafts for the tens-
drum and hour-drum, trip-levers which are arranged to be actuated by trip-fingers
on the bands for the units-drum and tens-drum respectively. The release of the
stop-pawl from the units-drum at the proper time is provided for by employing
an electrical releasing device such as that above mentioned, or any other suitable
releasing device controlled by a master-clock.
To prevent slipping or displacement of the bands or ribbons relatively to their
wheels or drums, I form perforations in the said drums at equal distances apart
around the same and corresponding perforations in the bands or ribbons, and I
provide sprocket-wheels mounted on suitably-supported spindles and adapted to
engage in the said perforations in the band and in the drums.
I sometimes provide for illuminating the drums or bands, for example, by
suitably-arranged electric lamps, so as to effectively indicate the time at night.
By employing the endless bands or ribbons I am enabled to obtain the further
advantage that I can illuminate the same from the interior thereof directly in rear
of the numerals. For this purpose I preferably arrange one or more electric lamps
within the space enclosed by each band or ribbon.
It is evident that I can somewhat modify the construction of my apparatus
without departing from the nature of my said invention.
ני.
DOLL
11907
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
Improvements in Mechanical Time-indicators.
I, SAMUEL POWERS THRASHIER, of New Haven, Connecticut, United States of
America, Engineer, 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 mechanical time-indicators of the kind or class in which
the hours and minutes are indicated by numerals visible through an opening or

page_text: openings in the face or front of the casing of the apparatus, the said numerals
being changed at the proper times by the step-by-step rotation of one or more of a
series of wheels or drums.
I find it advantageous to employ three of these wheels or drums mounted upon
a common axis, one for indicating units of minutes, another for indicating tens
of minutes and the third for indicating the hours, and to mark the numerals for
indicating the time of day either upon the said wheels or drums themselves, or
upon endless bands or ribbons passing over the said wheels or drums.
I provide suitable mechanism whereby power will be constantly applied to the
said wheels or drums separately for the purpose of turning the same, and devices,
controlled by a master time-movement or clock, whereby the said wheels or drums
will be restrained from rotation and will be released at the proper intervals to
permit the required step-by-step rotation thereof. For this purpose I employ in
combination with the separately driven wheels or drums, stop-pawls mounted on
separate shafts and adapted to engage with projections or fingers upon the drums
or upon endless bands or ribbons passing over the same. And I provide an elec-
trical or other releasing device for momentarily disengaging the stop-pawl from
the units-of-minutes drum, and means whereby the stop-pawls of the tens-of-
minutes and hour-drums respectively will be momentarily disengaged once in
each revolution of the preceding drum.
Another feature of my present invention is an improved construction of the
apparatus whereby I am enabled to advantageously employ endless bands or ribbons
which are passed over the said wheels or drums and have marked upon them the
numerals for indicating the hours and minutes. By employing endless bands or
ribbons in this manner, large figures can be used for indicating the time of day
without the necessity for employing drums of large diameter. This arrangement
is, therefore, very advantageous for use on towers or in other places where the
time has to be shown so that it can be easily read at a long distance.
My said invention also comprises other improvements hereinafter described.
In the accompanying drawings I. have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a front elevation of one form of my improved time-indicator, some
of the parts being removed or broken away.
Figure 2 is a side elevation of the same.
Figure 3 is a side view showing the train that operates the tens-of-minutes
drum.
Figure 4 is a side view showing the train that operates the hour-drum.
Figure 5 shows a portion of Figure 1 drawn to an enlarged scale.
Figure 6 is a similar view to Figure 2, some of the parts being removed.
Figure 7 is a section on the line a, a, Figure 5, looking towards the right.
Figure 8 is a section on the line a¹, a¹, Figure 5, looking towards the right.
Figure 9 is a section on the line a, a, Figure 5, looking towards the left and
Figure 10 is a section on the line,, Figure 5 looking towards the right,
these four sections being drawn to the same scale as Figure 6.
Figure 11 is a horizontal section showing the arbors for winding the different
movements.
Figure 12 is a perspective view showing the pawl-shafts and their pawls and
supports in connection with the wheels or drums, the latter being shown by dotted
lines.
Figure 13 is a side elevation, drawn to an enlarged scale, of an electro-magnetic
releasing device hereinafter described.
Figure 14 is a front elevation showing a tower provided with my improved
time-indicator.
Figure 15 is a front elevation showing another form or modification of my
improved time-indicator, in which I employ endless bands or ribbons.
Figure 16 is a side view of the same.

page_text: sprocket wheels and smarts.
Figure 18 is a plan or top view of the perforated idle drums with their sprocket-
wheels and shafts.
Figure 19 is a perspective view of one of the carrying-drums, showing the
ribbon and a trip-bar or trip-finger attached to it and engaging with one of the
releasing pawls.
Figure 20 is a sectional view showing the method of fastening the trip-fingers
to the ribbons.
Figure 21 is a plan of a stiffener for the ribbons, having a trip-finger formed
thereon.
Figure 22 is a plan of a stiffener made without a trip-finger.
Figure 23 is a horizontal section showing the winding arbors, and means for
keeping taut the parts of the endless bands or ribbons exposed through the open-
ings in the casing, and
Figure 24 is a perspective view of the pawls and shafts, the carrying-drums and
ribbons being shown by dotted lines.
Figure 25 shows a portion of Figure 15 drawn to an enlarged scale.
Figure 26 is a section on the line y, y, Figure 25, looking towards the left
showing one of the trip-pawls.-
Figure 27 is a similar section, looking towards the left, showing the restraining
pawl for the units-of-minutes drum.
Figure 28 is a section on the line y¹, y', Figure 25, looking towards the left.
Figure 29 is a section on the line y2, y2, Figure 25, looking towards the right,.
and
Figure 30 is a section on the line y³, y³, Figure 25, looking towards the right,
these five sections being drawn to the same scale as Figure 16.
A, A are brackets upon which are supported three movements
or trains of
gear B, B1, B2, each actuated by a weight or spring and adapted to drive one or
other of the wheels or drums D, D¹, D². By these means power is constantly
applied to the said drums separately so as to rotate them when released for the
purpose of effecting the required change in the time-indications. The gearing of
the several movements is calculated with reference to the difference in the periods
of revolution of the several drums in such a manner that the weights will run down
to their lowest limit in about the same length of time.
I have shown in Figures 11 and 23, arrangements of winding arbors whereby
the several weights can be wound up from one side of the apparatus.
The drum D is provided with numerals representing the units of minutes, and
the drum D with two sets or series of numerals representing the tens of minutes,
two series of numerals being used so as to make the drums of equal size or nearly
The drum D2 is provided with numerals representing the hours.
So.
For controlling the movements of the wheels or drums D, D¹, D², stop-
pawls Q, Q, Q, (Figures 1 to 12) provided with weighted arins e, e¹, e² respectively,
are mounted on separate shafts R, R1, R2, and engage with stop-fingers P on the
said wheels or drums. On the shafts R1, R2 are fixed releasing-pawls or trip-
pawls T, T¹ respectively, which are adapted to be actuated by trip-fingers 0,0¹ on
the drums D, D¹ respectively, for the purpose of releasing the drums D¹, D² at the
proper times. The stop-pawl Q of the units-of-minutes drum D has suspended
therefrom a rod or link W provided at its lower end with an adjustable collar or
nut Y. For drawing this rod W downward to release the drum D, I provide a
suitable releasing-device controlled by a master time-movement or clock. I find
it advantageous to employ, for this purpose, a releasing-device comprising an
electro-magnet 6 (Figures 1, 5 and 13) electrically connected with any well-known
device (not shown in the drawings) actuated by a master time-movement or clock,
for completing and interrupting the circuit once every minute. The armature of
this magnet is attached to a lever a having a spring extension Z, to the extremity
of which is attached a head or hammer X. This hammer is made with a hole or

page_text: slot S through which extends the rod W, and the said hammer normally rests a
short distance above the collar or nut Y on the said rod. When the armature-
lever a is drawn upwards by the magnet 6 to a position indicated by dotted lines
in Figure 13 and then released, the hammer X, by reason of its momentum,
descends below its normal position and strikes the collar or nut Y, and then
immediately resumes its normal position, indicated by full lines in Figure 13;
the said hammer thus momentarily disengages the stop-pawl Q from one stop-
finger P and permits the partial rotation of the drum D, but allows the said pawl Q
to return to its normal position in time to engage with the next succeeding stop-
finger P.
When the drum D has made one revolution, the trip-finger O thereon acts upon
the trip-lever T, Figure 7, and momentarily disengages the pawl Q₁ from the
drum D¹, Figure 8, so as to permit the turning of the said drum through an angle
sufficient to expose the next succeeding figure through the opening in the casing.
The drum D2 is turned in like manner once in every revolution of the drum D¹,
the trip-finger O¹ thereon acting upon the trip-pawl T¹, Figure 9, so as to moment-
arily disengage the pawl Q³ from the said drum D³, Figure 10.
As a means of positively ensuring the return of the said stop-pawls to their
normal position, their respective arms e are arranged to be depressed by the next
stop-finger passing them, should they not be otherwise caused to return to their
normal position.
To provide for setting the time-indicating mechanism by hand, levers V are
fixed on the separate shafts R, R1, R2 at one side of the apparatus, so that each drum
can, at any time, be allowed to turn about its axis without affecting the other
drums.
In the form of my apparatus shown in Figures 1 to 13, the arrangement of the
numerals and the openings through which they are exposed are substantially the.
same as described in the Specification filed in respect of my application for Letters
Patent No. 10770 dated 30th April 1897.
I sometimes make the rims of the drums D, D1, D2 of celluloid or other suitable
transparent material, and arrange electric lights f, f between the said drums as
shown so as to plainly display the time at night.
In Figures 14 to 30, I have shown a modification of my time-indicator wherein
I employ endless bands or ribbons E, E', E2 having the numerals marked thereon.
These endless bands or ribbons are passed around carrying-drums D, D¹, D³ and
also around idle drums F, F1, F2, and I provide sprocket-wheels J which engage in
perforations H, I in the ribbons and drums, respectively, and thus prevent slipping
of the said ribbons upon the carrying-drums D, D', D2 and keep the said ribbons
in proper line while travelling over the idle drums F, F1, F2. The movement of
the carrying-drums D, D', D2 is effected by power constantly applied to the said
drums respectively as above described, and is controlled by a suitable releasing-
device, Figures 25 to 30, similar to that hereinbefore described, acting through
the medium of the rod or link W upon the pawl Q of the drum D, as above
described. The idle drums F, F1, F2 are used simply to keep the bands or ribbons
taut.
In this arrangement, the trip-fingers 0, 0¹ are carried by the ribbons E, E¹ of
the units and tens-of-minutes drums D, D¹ respectively, as shown in Figures 19,
24, 26 and 28. The levers V upon the shafts R, R1, R2 may be suitably weighted
so that they will move the pawls Q, Q1, Q2 back into engagement with the stop
fingers P after each displacement.
Flat pieces 03 of steel or other suitable material as shown in Figure 22, serve
to preserve even the surface of the ribbons. The perforations H in the ribbons,
are provided with eyelets H through which the teeth of the sprocket-wheels J
freely pass to enter the perforations in the drums; these eyelets serve also to fasten
the flat pieces of steel to the ribbons as shown in Figure 20; the aforesaid trip-
fingers 0, 0¹ can, if desired, be conveniently formed on the said strips 03 as shown,
for example, in Figures 20 and 21.

page_text: .
The front plate M is provided with guides N, N (which may be of glass or other
suitable material) to ensure close proximity of the ribbons to the openings therein,
and the said guide-rods and front plate are arranged a short distance in front of
the carrying-drums and idle drums, as shown more clearly in Figure 16, so that
a slight degree of tension will be exerted upon the ribbons sufficient to ensure
evenness of the exposed surface of the ribbons; this arrangement also particularly
adapts the device for use in a large tower.
When endless bands or ribbons such as E, E1, E2 are employed it is evident that
numerals of large size can be displayed upon the bands or ribbons without increas-
ing the size of the drums, and better illumination of the figures may be obtained,
since the artificial lights f can be disposed within the said bands or ribbons
directly in the rear of the openings in the front-plate as represented in Figures 15
and 16.
It is evident that other modifications in the construction and relative arrange-
ment of the parts herein shown and described may be made without departing
from the nature of my said invention.
I do not confine myself to the employment of an electrical releasing device, as
it is obvious that I can, if desired, use any other suitable form of releasing device
for the purpose of controlling the movement of the wheels or drums.
It is obvious, moreover, that the aforesaid endless bands or ribbons can be used
on wheels or drums to which step-by-step rotation is imparted by means other than
those above described: for example by any of the means described in the Speci-
fications filed in respect of my applications for Letters Patent dated 30th April
1897 No. 10770 and No. 10778.
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 an apparatus for indicating the time of day, the employment of a series
of wheels or drums to which power is constantly applied by separate movements
or trains of gear, and which are restrained from rotation by means of suitable
devices adapted to be disengaged at regular intervals determined by a master
time-movement or clock, for the purposes above specified.
2. A time-indicator of the kind or class hereinbefore referred to, in which wheels
or drums mounted upon independent shafts in line with each other, are provided
with separate driving movements or trains of gear, and are restrained from robation
by separate stop-pawls which are momentarily disengaged at the proper times
through the medium of a single releasing device controlled by a master time-
movement or clock, for the purposes above specified.
3. The combination of the separately-driven wheels or drums, the stop-pawls
mounted upon separate shafts, a releasing device controlled by a master time-
movement or clock for momentarily, disengaging the pawl of the units-of-minutes
drum at the proper times, and means whereby the pawls of the tens-of-minutes
drum and the hour-drum respectively will be disengaged at the proper times by
the action of the preceding drum, substantially as hereinbefore described.
4. The combination of the wheels or drums provided with the projections or
stop-fingers, and the stop-pawls adapted to engage with the said stop-fingers and
provided with weighted arms or tail-pieces which, when the pawls are disengaged
from the said fingers, will project into the path of the latter, substantially as, and
for the purposes, set forth.
5. The combination, with the wheels or drums and the stop-pawls mounted on
separate shafts, of trip-pawls on the pawl-shafts of the tens-of-minutes drum and
hour-drum respectively, adapted to be actuated by trip-fingers on the units-of-
minutes and tens-of-minutes drums respectively, substantially as, and for the
purposes, above specified.
6. A time-indicator of the kind or class herein before referred to, in which
suitable provision is made for setting the separately-driven wheels or drums

page_text: independently of each other in the forward direction by an intermittent motion
under the action of the driving movement or train, and in the reverse direction
by hand, substantially as herein before described.
7. The provision of suitable means whereby the wheels or drums can be set
independently of each other by hand from one side of the apparatus, substantially
as described.
8. In a time-indicator, the employment of a series of endless bands or ribbons
bearing the numerals for indicating the time of day, and passed around wheels or
drums to which step-by-step rotation is imparted, for the purposes above specified.
9. The combination, with the separately-driven wheels or drums and means for
restraining them from rotation and releasing them at regular intervals, of endless
bands or ribbons bearing numerals, passed around and driven by the said wheels
or drums, substantially as, and for the purposes, herein before described.
10. The combination of the endless bands or ribbons passed around the inter-
mittently-rotating wheels or drums, and means for positively maintaining the
said bands or ribbons in their proper relation to the said wheels or drums, substan-
tially as described.
11. The endless band or ribbon having pieces of steel or other suitable material
secured thereto to stiffen the same, and provided with the trip-fingers for releasing
the stop-pawls, substantially as described.
12. The combination, with the stop-pawl for the units-of-minutes drum, of a
rod or link depending therefrom and adapted to be momentarily depressed at
regular intervals by a device controlled by a master time-movement or clock, for
the purpose above specified.
13. The improved electrical releasing device for momentarily disengaging the
stop-pawl from the units-of-minutes drum, substantially as described.
14. The front-plate and the guide-rods or rollers for the endless bands or ribbons,
so arranged relatively to the drums as to maintain under a suitable tension that
part of each band or ribbon displayed, for the time being, through the aperture
in the said front-plate, substantially as described.
15. The employment of drums or of endless bands or ribbons made of celluloid
or other suitable transparent or semi-transparent material so that the numerals
thereon can be clearly displayed at night, by means of an artificial light, as above
described.
16. The improved time-indicator constructed substantially as described with
reference to Figures 1 to 13 or with reference to Figures 14 to 30 of the drawings,
and operating as above specified.
Dated this 29th day of January 1898.
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.