An Improved Device for Indicating the Difference of Velocity of Two Clock Works.
Year: 1897

page_text: Date of Application, 30th Mar., 1897-Accepted, 30th Mar., 1898
COMPLETE SPECIFICATION.
An Improved Device for Indicating the Difference of Velocity of
Two Clock Works.
I, PAUL EIBIO, of Annenstrasse 16, Berlin S, in the Empire of Germany,
Mechanic, 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 is intended to indicate directly the difference of speed of two clock
works for instance for use in electric meters, without the functions of the iudicating
work having adverse influence on the clock works themselves.
The principle of the arrangement is, that the one clock, for instance I whilst
making a certain movement, for instance half a revolution, operates the coupling of
the other clock work II with the countor, and after this clock work II together with
the counter, bas turned a certain distance in one direction for instance to the left, the
former clock work I releases the counter from the clock work II and couples
itself with the counter during an equally long poriod for instance half a revolution
and turns the same again back to the right for a certain distance, so that thus only
the difference of the distances traversed by the clock works I and II is indicated
on the counter.
The turning to the left effected by the clock work II during the first movement
need not be shown on the indicating part of tho counter, as long as the difference
between the left and right movements is duly indicated.
The coupling of the clock work can be effected either elastically, by crank pins,
or toothed wheels, or the like in different ways.
Instead of letting one clock after the other operate on the counter during equal
periods of time as measured by the one clock work, the coupling of the one clock
work with the counter can be only momentary and the connection of the other
work with the counter can then remain almost constant and is only disengaged
during the momentary opposite effect of the first clock work.
The operations of the two clock works on the counter can of course be exchanged
at pleasure and the duration of their respective operation may be arranged as
required.
The characteristic feature of this construction is, that the two clocks operate
successively and not simultaneonsly on the counter, so that during the operation
by the one clock, that is for instance during only one movement, the effect of the
other clock on tho counter is stopped; the time rate of the two clock works is not
influenced perceptibly by the movemont of the counter.
This constructive idea can be executed in various ways according to the uses it
may be put to.
The simplicity of the principle is such that a schematic representation of the
general system of this differential meter is not necessary.
Therefore in the annexed drawing there is shown as an example only a specially
practical form of construction.
In this example the connection of the one clock work with the counter is shown
as nearly constant, that of the other is only momentary and the coupling is effected'
elastically.

page_text: This arrangement offers special practical advantages over the other forms and
these will be explained hereinafter.
The one clock work I turns constantly during its motion a disk 2, which is fixed
upon the axle 1 of this clock work. With this disk 2 there moves a dog 4 seated
excentrically on the latter at the point 3 and pressed into the star wheel 6 by means
of the spring 5. By means of this elastic coupling tho star wheel 6, loose on the
axle 1, is turned, for instance to the left, during the operation of the clock work I.
With this coupling wheel 6 is solidly connected a ratchet wheel 19 and also a
toothed wheel 7 which latter is in gear with the wheel 8. On this toothed wheel 8
is au excentrically placed driving pin 9 which moves with free play iu a slot 10 of
the wheel 11 the axis of which is concentric with the whool 8 but can turn
independently thereof. The wheel 11 by means of the toothed wheels 12 and 13,
drives the axle 14, upon which bosides the first counter disk 17 there is arranged
also an escapement wheel 16, the movement of which is regulated in the usual
manner by means of an oscapement 15. The further counter disks 18 etc. are
driven from the first axle 14 by means of gearing in the proportions of 1 to 10.
By this arrangement the clock work I acts upon the differential counter during
the revolution of the clock work I, through the coupling before described and
whools 7 and 8, the latter turning to the right whilst the axlo 1 turns to the left.
The driving pin 9 on the wheel 8 moves under uorinal circumstances in the
slot 10 of the opposite separately mounted wheel 11, so that no displacement or
turning of the counter disks 17 18 etc. takes places.
When however the driving pin 9 presses against the rear end of the slot 10 and
tends to move the wheel 11 and consequently the counter, the ratchet wheel 16 and
the escapoment 15 hinder such backward displacement of the counter, as the
escapoment 15 only lets the ratchet wheel 16 revolve in ono direction namoly
forwards.
Contrarily to the clock work I, it is desirable to let the other clock work II
operato on the counter only for a moment and this in an opposite direction to clock
work I, that is, for instance, turning to the right.
This sudden operation cau be effected either mechanically or electro-
magnetically.
In the annexed drawing this arrangement is shown in connection with electro
maguetic clock works, there being upon the axle 20 of the clook work II a cam
disk 21, which, after a certain poriod, for instance regularly at each revolution of
the axle 20, closes momentarily a contact 22 and thus excites an electro magnet 23,
which attracts its armaturo 24.
The contact arrangement and the electro magnet are shown only schematically
as their construction is not of consequence in the present connection, and the
drawing only shows au example of the momentary or short operation of the effect
of the clock work II upon the counter, which oporation may be effected either in a
mechanical or an electro maguetic manner.
The electro magnetic arrangement possesses special advantages, because greater
efforts of power can be obtained therewith and the clock work operating the
disengagement has then no percoptible work to do.
A direct operation of electrical winding up mechanism can accompany this
periodically operating arrangement.
With the armature 24 of the electro magnet is connected a lover 25, on which is
provided a dog 27 seated elastically against the spring 26.
Since, at regular intervals, that is, each time after the clock work II has run a certain
distance, for instance one revolution, the armature 24 and with it the dog 25 dre
moved to the right, the latter pushes the fine toothed ratchet whool 19 forwards for
a certain distance, for instance to the right.
Simultaneously the elastic power of the spring 5 is overcome by the shock and
the star wheel 6 slides for one tooth to the right under the pawl 4.
This forward movement of the star wheel operated periodically by the clock

page_text: work II is each time equally long but these periodical part revolutions to the right
would of course be effected at shorter intervals of time after one another, the
greater the velocity of the clock work II.
Therefore during the momentary operation of the clock work II upon the
counter the elastic coupling of the latter with the clock work I is interrupted or
overcome.
Instead of the star liko form here represented for the coupling device there may
be used any other angular or excentric forin.
Further, instead of this disengagement of an elastic coupling of the clock work I
with the counter, interruption can also be made for instance by a lever 25
completely disengaging for a moment the coupling and driving gear, which forms
the connection between the clockwork I, and the connter and brought again into
operation after the counter has already been pushed forwards by the clock
work II.
There remains only the explanation of the manner of operation of the differential'
counter.
After the clock work I as already described has moved to the left the driving
pin 9 in the slot 10 the clock work II as already described pushes the ratchet
wheel 19 in the opposite direction, for instance to the right, and thus moves the
pin 9 a certain distance to the right. The length of this latter movement
must always be the same as at each such movement a tooth of the star wheel 6
slides under the pawl 4 whilst the movement to the left by the clock work I may
vary.
Supposing that clock work II has a quicker movement than I, for instance whilst
clock work II makes 240 oscillations clock work I may make only 210 oscillations
in a minuto, thorofore clook work II makes in each minute, 30 oscillations more
than the clock work I.
Whilst tho clock work I has moved the pin 9 a distance equivalent to its 210 oscilla-
tions for instance for a length of 7 millimeters backwards in the slot 10 the quicker
running clock work II according to its 240 oscillations made during the same
time will at once after this push the pin 9 with a shook forward, for 240
x7=8mm.
210
This difference in the travel of the pin, that is, its displacement of 1 mm.
corresponds therefore to a difference of motion of the two clocks of 30 oscillations
a minute.
The pin 9 at the end of this forward push of 1 mm. (80 oscillations) will not yet
have reached the end of the slot 10, therefore the counter 17 etc. will not yet be
turned forwards; these 30 oscillations difference between the clock-works are
therefore not yet indicated but the pin compared with its position at the beginning
of the period is already 1 mm. nearer the end of the slot. During the next.
following period of motion of the two clock works there would be added a further
displacement of 1 m., provided that the previous difference in motion of the two
clock works remains the same, the forward push of the driving pin 9 by the clock
work II surpasses by 1 mm., the backward movement of the same by the clock
work during the same period. The forward movements of the driving pin 9 are
added successively corresponding to the addition of the differences of velocity.
The forward revolution of the counter is effected when the pin 9 after having
reached the end of the slot 10 presses against that end and moves the wheels 11, 12
etc. forwards and hereby also the counter disks 17 dlc.
As it is desirable to effect this successive forward movement of the counter
disks 17 etc., not as would be the case according to the above description, that is to
say very slightly in each interval, in fact almost in a creeping or sliding manner,
but to transform it into an equal forward springing movement, a ratchet wheel 16
is as already described connected with the first counter axlo 14, the revolution of
this wheel 16 being regulated in such a manner by the anchor escapement 15, that
when the pin 9 commences to press on the end of the slot 10 the pressure being

page_text: transferred to the wheel 16 causes it to run suddenly forward each time one tooth's
width only, corresponding for instance to a difference of 40 oscillations.
This movement, oarried through the gearing, coincides with a similar movement
of the wheel 11 so that the latter moves intermittently in the same manner and at
the same time as the wheel 16. The slot 10 thus moves suddenly in advance of the
pin each time that the latter presses on the end of the slot.
The pin 9 has thus each time to recover the distance equal to the forward
advance of the slot before again operating the counter, and supposing that the
counter disks aro so marked as to give a true indication equivalent to the position
at tho time of the pin 9 when the forward springing of the wheel 16 has just takon
place, it will be obvious that no further differences will be marked on the counter.
until the pin has recovered the aforesaid distance when another 40 oscillations
difference will be suddenly indicated and so on. Thus differences less than
40 oscillations remain in abeyance so far as their indication on the counter is
concerned, until they attain a sum of 40 oscillations.
As already mentioned this escapement 15 and wheel 16 provent the counter from,
moving backwards for instance with a reversed ratio between the speeds of move-
ment of the two clock works.
Excess speed of clock work I must therefore be compensated in another manner
since excess of velocity of the olock work I, would possibly cause clook work II to
be stopped or damaged.
This compensation for reversed ratio of movemont is effected in a peculiar manner,
namely by the operation of the elastic coupling in the following manner: since as
already mentioned, the escapement 15, 16 stops the counter wheels and the toothod
wheels 12 and 11 against backward movement, in this case these said devices may
be considered as immovably fixed. Consequently in case the clock work I in any
period gives a greater revolution of the star wheel 6 to the left than the revolution
to the right by the clock work II the pawl 4 which turns permanently further to the
left with the disk 2 will be pressed graudally out of the teeth of the star wheel 6 which,
as can be seen, is in this case immovable backwards, until the pawl 4 falls over the
next tooth into the following indent. By this successive sliding of the pawl 4
backwards over the teeth of the star wheel 6 the reversed ratio of movement which
is not to be indicated of the clock work I compared with that of II is thus com-
pensated and made harmless; the elastic power of the pawl spring 5 which is to be
overcome, being so small that the movement of the two clock works is not
hindered.
In practice one might also easily prevent the indicating of unintended differences
of motion of the two clock works by means of this escapement and compensation, if
for instance the two clock works have under normal conditions exactly the same
velocity, in the course of a long time there would gradually arise a perceptible
indication on the counter in consequence of possible deficiency in exact regulation,
if the clock work II obtains a forward movement, howevor small in relation to the
clock work I, even without the aid of exterior forces which would influence its
velocity. The measurement of the difference may be ascertained by employing this
invention.
In order to avoid in this case too subtle regulation of the clocks of normally
equal volocity, the regulation would be such as to slightly favor clock work I,
giving to this clock work I at a normal movement a slightly greater velocity than
the clock work II.
This minimal advance of I would however, as already explained, not be indicated
by the counter in consequence of the stoppage against backward movement and of
the elastic coupling and therefore not impair the indication.
It can be soon from the above description that thus by the alternate operation of
both clock works upon the countor effected at certain intervals not simultaneously
but one after the other, the differences of the clocks are added exactly in the same
direction and that an inverted indication is avoided. The movement of the clocks
themselves is not perceptibly altered by the operations of the counter, especially

page_text: when the forward push of the counter work is operated by electric mechanism and
not by the clock itself.
This arrangement can be made by weights, springs or the like in different
combinations and with different applications of the operations of the singlo dovices,
as previously explained, and for clock works with either electric or mechanical
winding gear.
The form of construction shown in the annexed drawing and described more
particularly heroinbefore with momentary and suddenly effected operation of the
one clock work on the counter offers also this practical advantage, that the counter
can be constructed with forward springing numbers; the forward springing of
tooth after tooth is already explained in, the description.
It is evident that in this arrangement the effort of force for counters with forward
springing numbers is given by the electric mechanism, without the clock works
themselves having to perform this work, as is unavoidable in other constructions.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. An improved device for indicating the difference of velocity of two clock or
going works, in which the one clock work actuates poriodically a coupling, after
having travelled certain distances, in such a manner, that both clock works one
after the other operate on a counter in a sense opposed to one another during
certain equal time periods of the one clock work, whereby the advancing of the
one clock work before the other one is indicated on the counter at certain intervals
and the differences of travel effected during the different periods are added
together.
2. A device as under Claim 1 characterised by an elastic escapement coupling
which, effecting the almost permanont connection of the ono clock work with the
counter, is overcome during the short effect of the other clock work upon the
counter by means of the greater counter force and is thus hindered in its effect, for
the purpose of allowing a permanent exact indication of the differences produced,
without hindering or influencing the clock movement and to compensate by the
elasticity of the coupling for an inverted effect upon the counter.
3. A device as in Claims 1 and 2, in which the sudden operation at certain
intervals of the pue clock work upon the counter is produced by the winding up of
gear of the clock works operated periodically by the clock work for the purpose of
moving the counter also by the thrnst given to this gear without hindering the
clock movement.
Dated this 30th day of March 1897.
HERBERT HADDAN & Co.,
Agonts to Applicant, 18, Buckingham Street, Strand, London.