IMPROVE- MENTS IN CLOCKS AND OTHER TIMEKEEPERS
Year: 1877

page_text: LETTERS PATENT to William Gillett and Charles Bland, both of Croydon, in
the County of Surrey, Clock Manufacturers, for the Invention of "IMPROVE-
MENTS IN CLOCKS AND OTHER TIMEKEEPERS."
Sealed the 29th June 1877, and dated the 2nd January 1877.
PROVISIONAL SPECIFICATION left by the said William Gillett and Charles
Bland at the Office of the Commissioners of Patents on the 2nd January
1877.
WILLIAM GILLETT and CHARLES BLAND, both of Croydon, in the County of
Surrey, Clock Manufacturers. "IMPROVEMENTS IN CLOCKS AND OTHER TIME-
"
KEEPERS."
This Invention has for its object improvements in clocks and other timekeepers,
and consists in the application of arrangements of mechanism by which a constant
equal force is applied to the escapements of timekeepers so as to obtain accuracy in
the time recorded by means of our improvements, which are applicable either to the
indication of the time by means of hands and numerals, as is well understood, or by
means of numerals brought forward opposite to an aperture or apertures on the face
or dial of the clock or timekeeper.
This improved remontoire action is designed to make the force on the escapement
of a turret, clock constantly equal, and to allow the hands to advance by sudden
jumps at regular intervals, such as one minute or half a minute, so that the time
can be more accurately distinguished from a distance.
And in order that our improvements may be more clearly understood we will
proceed to describe the Drawings annexed.
The apparatus consists of two weights A¹ and A³ (as shown in Figures 1 and 2 of
the Drawings) attached by cords to levers B1 and B2, with segments for winding the
cords on. The levers have clicks C¹ and C², to connect them with the escapement
by the wheel W on which they alternately ride, thereby driving the escapement,
one weight being separated from the wheel W and wound up by the clock, while
the other is in action with the wheel and entirely detached from the clockwork.
This is effected by two cams D1 and D2 fixed in opposite positions on the last arbor F
of the clock train, which is turned half way round at intervals, thereby reversing
the position of the cams D' and D³. To each lever is attached a spring E¹ and E³
17

page_text: projecting in the direction of the cams, so that one cam D¹ in revolving comes in
contact with the roller on spring E¹ and forces it back in opposition to the pressure
of the weighted lever on the wheel W at C¹. Thus the resistance of the spring E¹
gradually increases until it becomes equal to the force of the weighted lever B¹
(when the pressure at C¹ is entirely counteracted) and the continued motion of the
cam D' raises the lever E¹ off the wheel W up to its highest position, when the
motion stops, and the weighted lever B remains supported on cam D¹ by the
spring E¹ until the cam arbor is again liberated.
While the acting force of this weight A¹ was thus being gradually removed from
the wheel W to the cam D¹, the pressure of the other weight A³ was being trans-
mitted in the same proportion from the cam D to the wheel W. For instance,
when the cam D¹ has forced the spring El so far back that its resistance equals half
the weight of A¹, so that half the pressure at C¹ has been counteracted, then the
other cam D2 which has moved through the same distance as D¹ has relaxed its
spring E to exactly the same degree of strength as E¹, thereby transferring half of
the pressure of A² from the cam on to the wheel, the other half still pressing on the
spring E2, then half the force of each weight is acting on the wheel. In the same
way the combined pressure on the wheel of the two levers in any other position of
the cams are always equal to the total pressure of one, thereby keeping a uniform
force on the escapement.
The cam arbor which is turned by the clock train is stopped in its motion by two
arms G¹ and G2 projecting from the cam arbor, alternately coming in contact with
two short arbors Hand H2, which have notches in them for liberating the arms
again. The whole of this portion is separate from the escapement:
'
We will now describe our improvements in chronoscope actions for showing
numerals opposite an opening.
The object of this arrangement is to enable the drums to be set backward as well
as forward independently of each other, and this plan allows a more uniform pressure
on the escapement, and is equally suitable for watches as for clocks.
The train wheels of the movement and the drums are arranged together, one
wheel a and pinions C (as shown in Figures 3, 4, 5, and 6) being pivotted in each
drum eccentrically, and another pair B, B, between the drums in a central position,
which pair gear with the wheel a in one drum and the pinion C in the next drum,
so forming the train of wheels, to which a spring or weight is connected at one end
and the escapement at the other. This position of the wheels and pinions enables
the force in being transmitted to the escapement (at the same time) to impart energy
in turning the drums, each drum having teeth and a pair of pallets which are acted
on by a projection on the next drum or on one of the wheels, so as to liberate the
drum and stop it again when it has moved the 'required' 'distance for changing the
figure, and there to hold it still till the correct time for shifting to another figure, by
which time the wheel with its projection has travelled to a corresponding position
and again liberates the drum; thus each drum with its teeth' and pallets form a
separate escapement independent of the others, although all are driven by one weight
or spring.
The wheel and pinion, which are placed in an eccentric position in the drum, are
attached to it by a spring to relieve the wheel work of concussion as well as 'to
increase the rapidity of action of the drum.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Gillett and Charles Bland in the Great Seal Patent Office
on the 2nd July 1877:
_ 1..
WILLIAM GILLETT and CHARLES BLAND, both of Croydon, in the County of
Surrey, Clock Manufacturers. “IMPROVEMENTS IN CLOCKS AND OTHER TIME-
KEEPERS.
"
i

page_text: This Invention has for its object improvements in clocks and other timekeepers,
and consists in the application of arrangements of mechanism by which a constant
equal force is applied to the escapements of timekeepers so as to obtain accuracy in
the time recorded by means of our improvements, which are applicable either to the
indication of the time by means of hands and numerals, as is well understood, or by
means of numerals brought forward opposite to an aperture or apertures on the face
or dial of the clock or timekeeper.
This improved remontoire action is designed to make the force on the escapement
of a turret clock constantly equal as well as to reduce its friction, and to allow the
hands to advance by sudden jumps at regular intervals, such as one minute or half
a minute, so that the time can be more accurately distinguished from a distance.
And in order that our improvements may be more clearly understood, we will
proceed to describe the Drawings annexed.
The apparatus consists of two weights A¹ and A² (as shown in Figures 1 and 2
of the Drawings), attached by cords to levers B1 and B2, with segments for winding
the cords on. The levers have clicks C and C2 to connect them with the escape-
ment wheel W on which they alternately ride, thereby driving the escapement, one
weight being separated from the wheel W and wound up by the clock, while the
other is in action with the wheel and entirely detached from the clockwork. This
is effected by two cams D1 and D2 fixed in opposite positions on the last arbor F of
the clock train, which is turned half way round at intervals, thereby reversing' the
position of the cams D' and D². To each lever is attached a spring E' and E³, pro-
jecting in the direction of the cams so that one cam'D' in revolving comes in contact
with the roller on spring E' and forces it back in opposition to the pressure of the
weighted lever on the wheel W at C¹. Thus the resistance of the spring E¹
gradually increases until it becomes equal to the force of the weighted lever B¹ (when
the pressure at C₁ is entirely counteracted) and the continued motion of the cam D¹
raises the lever E¹ off the wheel W up to its highest position, when the motion
stops, and the weighted lever B' remains supported on cam D' by the spring E¹
until the cam arbor is again liberated.
While the acting force of this weight A¹ was thus being gradually removed from
the wheel W to the cam D¹ the pressure of the other weight A2 was being trans-
mitted in the same proportion from the cam D2 to the wheel W; for instance, when
the cam D has forced the spring E¹ so far back that its resistance equals half the
weight of A', so that half the pressure at C' has been counteracted, then the other
cam D2, which has moved through the same distance as D¹, has relaxed its spring E
to exactly the same degree of strength as E', thereby transferring half of the
pressure of A2 from the cam on to the wheel, the other half still pressing on the
spring E2, then half the force of each weight is acting on the wheel. In the same
way the combined pressures (on the wheel) of the two levers, in any other position
of the cams, are always equal to the total pressure of one, thereby keeping a uniform
force on the escapement.
When either weight is supported by the cam its pressure at the fulcrum rests on
the bearing G, and the hole in the lever through which the arbor of the wheel W
projects is a little larger than the arbor, and is held central with it by the bearing G,
so that the arbor, which continues revolving, does not touch the lever while the
lever is being held stationary by the cam, thus entirely detaching it from the
escapement. The other cam having advanced away from its levers leaves it pressing
on the wheel by its click, which then becomes a fulcrum, and the weight being
heavier than the lever raises it off bearing G to the scape arbor, against which it
rests, thus obviating the friction at G and separating the lever from everything
except the wheel on which it rides bodily. The cam arbor is driven by the clock
train, and stopped in its motion by its projecting arms (H¹ and H³) coming alter-
nately in contact with an arbor I, which has a notch in it for liberating them again;

page_text: '
this arbor takes the strain of the clock weight without causing friction, it being
motionless, except at the moment when it liberates the cam shaft, at which time it
is entirely detached from the escapement.
The liberation of cam shaft is effected by a very light arm J projecting from I
with a roller at its end, which rolls on a circular portion K of the wheel W; there
are openings in K, through which the roller falls, taking with it the arm J, so
turning I and letting H escape through the notch in I. The arbor I is immediately
set back again by the projection M on cam D acting against lever L on I, pushing
it back, and keeping it so till just before the motion of the cam shaft ceases, by
which time the opening in K has travelled past the roller, so that the roller can
again be supported by K. The roller must be small enough to completely fall during
one beat of the scape wheel, and the arin J should be so. light that its downward
motion will not commence as rapidly as K travels away from under it.
The action of the remontoire is more fully explained by reference to the following
diagram, showing the different positions of one cam and lever, the other cam and
lever being omitted, to prevent confusion. The cam arbor T is turned halfway
round at regular intervals by the clock train. The wheel W drives the escapement,
and is moving with uniform speed. The weighted lever L rides on the wheel W,
with which it is connected by a click on the lever against a pin P projecting from
the side of the wheel. The spring S, with its roller, is fixed to the lever L, and
when the cam revolves it presses back the spring, thereby raising the weighted
lever L off the pin P up to its highest position, when the motion of the cam ceases
and the lever remains supported by it, the other lever (omitted in Drawing) being
then in action with the wheel.
Figure 3 represents the lever L in action with the wheel W, on which it rides
through the distance C³ to B³, while the spring S moves upward from D2 to A2, and
its roller has just come in contact with the cam, as shown by Figure 4; in this
position the cam arbor is liberated, and as the cam moves from A to B₁ it presses
the spring down from A2 to B2, the lever L still riding on the wheel W, see Figure 5;
at this point the resistance of the spring S, which has been gradually increasing
(and so removing the force of the weighted lever from the wheel W) has now
become sufficient to lift it off the pin P, and by the continued motion of the cam
from B¹ to C¹ the spring is forced down from B² to C2 and the lever raised a
corresponding distance from B³ to C³, as in Figure 6, when the cam stops, liolding
the lever up in this position. The wheel W continues moving by the force of the
other weight, and when the second pin P2 on the wheel (and travelling with it) has
been brought in contact with the click on the lever L, as in Figure 7, the cam arbor
is again liberated, and while moving from C¹ to D¹ it gradually relaxes the spring
which follows it from C² to D2, the lever remaining at C3 on the pin P2, as in
Figure 8, then the spring has become entirely relaxed and the whole force of the
weighted lever is acting on the wheel W. The circular portion of the cam is simply
to prevent the swaying motion the spring would acquire if the cam left it
suddenly. The cam does not, stop at D¹ but continues to move on to A', leaving
the spring at D2, as in Figure 9, from whence it moves with the wheel W, as before
explained.
In considering the combined action of both levers it must be borne in mind that
the two cams are fixed on one arbor in opposite positions, which moves half a
revolution at intervals, thereby acting on the levers alternately, while the motion of
the wheel is continuous and regular.
If we suppose one cam and lever to be in the position of Figure 4, where the
weighted lever is riding on the wheel and its spring has moved up to the cam, then
the other lever and cam are represented by Figure 7, the lever being supported by
its spring on the cam. The pin P on the wheel W (and travelling with it) has
come in contact with the click on the lever, but the lever is not yet pressing on it;
at this moment the cam arbor is liberated, and during the motion of the cams
from Figure 4 to Figure 5, and from Figure 7 to Figure 8 respectively, their action
with the two springs is simultaneous though opposite, while both the levers are

page_text: remaining in contact with the, wheel W, but the pressure of them on the wheel W is
reversed; the spring of the first lever being pressed back has now become sufficiently
stiff to support the whole of the force of its weight, while the force of the other
which was pressing against the cam has been gradually transmitted to the wheel by
the relaxation of its spring, and these two acting portions of each cam are so formed
as to tighten one spring in exactly the same proportion as the other being loosened,
so that through the action from Figures 4 and 5 and Figures 7 to 8, the combined
pressures of the two weighted levers acting on the wheel Ware exactly equal to the
total pressure of one. The continued motion of the cam from Figure 5 to Figure 6
raises the weight and lever to its highest position, and there supports it while the
other cam in Figure 8 simply moves to a vertical position, Figure 9 leaving the
spring end to travel along with the wheel until its roller has again come up to the
cam, and the next pin on the wheel has come in contact with the click of the other
lever, when the cam arbor is again liberated and the process repeated.
We will now describe the arrangement for chronoscope action where the time is
shown in the same manner as in railway time tables instead of by ordinary hands
and dial; for instance, at half past ten, the figures 10.30 only are exhibited and
change instantaneously at every minute.
The object of this part of our improvements is to enable the drums or discs on
which the Figures are indicated to be set backward as well as forward independently
of each other, and this plan gives a more uniform pressure on the escapement, and
is equally suitable for watches as for clocks.
The train wheels of the movement and the drums are arranged together, one
wheel a and pinion c, as shown in Figures 10, 11, 12, and 13 of the Drawings
annexed, being pivotted in each drum eccentrically, and another pair B, B, between
the drums in a central position, which pair gear with the wheel a in one drum and
the pinion c in the next drum, so forming the train of wheels to which a spring or
weight is connected at one end and the escapement at the other. This position of
the wheels and pinions enables the force in being transmitted to the escapement (at
the same time) to impart energy in turning the drums, each drum having teeth and
a pair of pallets, which pallets are moved by a projection on the next drum or on
one of the wheels, so as to liberate the drum and stop it again when it has moved
the required distance for changing the figure, and there to hold it still till the
correct time for shifting to another figure, by which time the wheel with its
projection has travelled to a corresponding position and again liberates the drum;
thus each drum with its teeth and pallets form a separate escapement independent
of the others, although all are driven by one weight or spring.
The wheel and pinion which are placed in an eccentric position in the drum are
attached to it by a spring to relieve the wheel work concussion, as well as to
increase the rapidity of action of the drum.
Having thus described the nature of our Invention and the manner of performing
or carrying the same into practice, we would remark that we make no claim to any
of the mechanical parts herein shown and described separately, but what we
claim is,-
First. The improved arrangement and combination of mechanism for producing
a more equal force than heretofore on the escapement of clocks or other timekeepers
with less friction and more uniformity of force on the escapement, this result being
obtained by means of the "remontoire" arrangement of cams and springs, sub-
stantially in the manner and for the purposes herein-before described and represented
in Figures 1, 2, 3, 4, 5, 6, 7, 8, and 9 of the accompanying Drawings; we also claim
the method of preventing friction at the stops on the moving portions connected
with the escapement, and also the prevention of concussion on the same by causing
them to act on the stationary arbor I, substantially in the manner herein-before
described and shown in the Drawings annexed.
Secondly. We claim the improved chronoscope arrangement of mechanism con-
structed in such manner that cach drum contains its own moving force independent
of the others, so that they can be set to correct time much more easily, making

page_text: them less liable to disarrangement and giving more rapid action to the drums in
changing the figures, substantially in the manner herein-before described and
represented in Figures 10, 11, 12, and 13 of the Drawings annexed, instead of its
being applied to them suddenly by the clock work as heretofore, thereby varying the
pressure upon the escapement.
In witness whereof, I, the said William Gillett, have hereunto set my hand
and seal this Twenty-ninth day of June, in the year of our Lord One
thousand eight hundred and seventy-seven.
W. GILLETT. (LS.)