CERTAIN IMPROVEMENTS IN OBTAINING COMPENSATION FOR THE EFFECTS OF CHANGES OF TEMPERATURE IN TIMEKEEPERS
Year: 1859

page_text: LETTERS PATENT to William Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for the
Invention of "CERTAIN IMPROVEMENTS IN OBTAINING COMPENSATION FOR THE
EFFECTS OF CHANGES OF TEMPERATURE IN TIMEKEEPERS."-A communication
from abroad by Henry Boehm James, of Trenton, in the County of
Mercer, and State of New Jersey, United States of America.
Sealed the 20th April 1860, and dated the 22nd November 1859.
PROVISIONAL SPECIFICATION left by the said William Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on the
22nd November 1859.
I, WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of
the said Invention for "CERTAIN IMPROVEMENTS IN OBTAINING COMPENSATION FOR
THE EFFECTS OP CHANGES OF TEMPERATURE IN TIMEKEEPERS," to be as follows:-
This Invention consists in controlling the active length of the pendulous
spring, or, as it is generally termed, the "hair spring" of a watch or other
timekeeper governed by a balance wheel, or of the pendulum rod of a clock
which is governed by a pendulum. This object is effected by means of

page_text: combined laminæ of brass and steel or other metals, which expand and
contract differently with the same changes of temperature. These combined
laminæ are applied to that end of the said spring or rod which has heretofore
commonly been fixed, and they are adapted thereto in such a manner that by
their expansion and contraction they will cause the spring to be taken up
through its curb pins, or in the case of clocks the pendulum rod will be taken
up through its stud as it (the said spring or rod) expands with an increased
temperature, and it will be let out as it contracts with a reduction of
temperature.
The Invention is capable of being applied in a variety of ways, but it is
proposed generally to coil the combined laminæ of metal into a convolute spiral
form, and to attach the inner end of the coil firmly to one of the plates which
hold the movement, and either to attach the end of the hair spring or
pendulum rod to the other end of the coil, or to a bar or lever against which
that end of the coil acts in such a manner as to cause the said bar or lever to
move with the expansion and contraction of the coil produced by changes of
temperature, and so to take up or let out the spring or rod.
According to one plan of carrying out the Invention, the inner end of the
coil of the hair spring is connected with the staff of the balance wheel in the
usual manner, but the outer end, or as it is generally termed, the "spare "end
instead of being secured in the usual manner to a fixed stud secured in the
potence plate, is attached securely to a stud carried by an arm, which is formed
by the extension of the outer extremity of what I term the compensating coil.
The regulator is of the ordinary form, and is applied and furnished with curb
pins to receive the outer coil of the hair spring in the usual manner. The
compensating coil and its arm are made of a strip of brass and a strip of steel
united by soldering, brazing, or other means, the steel being on the outside of
the coil. The inner extremity of the coil is firmly secured by a screw to a stud
that is secured in the potence plate, but the outer extremity and its arm are
left perfectly free. The effect of an increase of temperature is to expand or
open the coil and raise the arm in an upward direction, and also to produce a
flexure of the arm in a similar direction, and so to draw the hair spring up
through the curb pins, and reduce its active length, and thus to compensate
for the expansion of the spring and the balance, and the effect of a reduction
of temperature is of course precisely the reverse. There are a number of
small holes provided in the coil, and by screwing a screw into any one of
these holes so as to clamp the coil tightly, all that portion of the coil between
the inner extremity and the said screw is rendered inoperative, and hence by

page_text: changing the position of the arm and moving the screw to one of the holes
further from the inner extremity of the coil, a less degree of compensation is
obtained, and by moving the said arm and screw to another of the said holes
the opposite effect is produced. Many other modes of checking the action of
a portion of the compensating coil on the hair spring may be used. The
regulator operates in the usual manner.
Another mode of applying the Invention differs from that above described in
having the outer or spare end of the coil attached by the stud to one end of a
bar whose other end is secured by a screw to a small plate that is secured by
screws to the potence plate, and in having a compensating coil applied, so that
its outer extremity presses against the bar. This compensating coil is like
that above described, except that its outer extremity is not continued to so
great a length in the form of an arm. The inner extremity of the said coil is
secured by a screw to a stud, which is fast in the fixed plate, and its outer
extremity is made of V or knife edge form to enter a notch in the com-
pensating bar; this bar must be made sufficiently elastic to keep bearing upon
the compensating coil notwithstanding the expansion and contraction of the
latter. The effect of the expansion of the compensating coil is to move the
bar upward, and make it take up the hair spring through its curb pins, and
the contraction of the said coil permits the bar to spring in the opposite
direction to let out the spring.
By another arrangement the coil is dispensed with, and a compensating bar
composed of laminæ of brass and steel above described, and applied in the
same manner is made use of to effect the whole amount of compensation. The
degree of compensation in this example is regulated by a screw and a number
of tapped holes in the fixed plate, which holds the said bar in the same manner
as described with reference to the other arrangements, the said screw rendering
a greater or less portion of the bar operative on the hair spring, according as it
is further from or nearer to the stud which attaches the hair spring to the said
bar, and so compensating more or less. The compensating bar may be nearly
straight or of any curved or of a reflex form.
There are many other forms in which the compensator may be constructed
for application to watches and other time keepers governed by balances, but
I consider it generally preferable to make it in the form of a coil, for the reason
that by it I am enabled to use as long a hair spring as is desirable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Edward Newton in the Great Seal Patent Office
on the 22nd May 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-second day of November, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Edward Newton, Her special license that I, the said
William Edward Newton, my executors, administrators, and assigns, or such
others as I, the said William Edward Newton, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "CERTAIN IMPROVEMENTS IN OBTAINING COMPENSATION FOR THE
EFFECTS OF CHANGES OF TEMPERATURE IN TIMEKEEPERS," being a communi-
cation from abroad by Henry Boehm James, of Trenton, in the State of
New Jersey, United States of America, upon the condition (amongst others)
that I, the said William Edward Newton, by an instrument in writing
under my hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Edward Newton, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawing hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
This Invention consists in controlling the active length of the pendulous spring,
or, as it is generally termed, the "hair spring" of a watch or other timekeeper
governed by a balance wheel, or of the pendulum rod of a clock, which is
governed by a pendulum. This object is effected by means of combined
lamina of brass and steel or other metals which expand and contract differently
with the same changes of temperature. These combined laminæ are applied

page_text: to that end of the spring or rod which has heretofore commonly been fixed,
and the metals are adapted thereto in such a manner that by their expansion
and contraction they will cause the spring to be taken up through its curb
pins; or in the case of clocks the pendulum rod will be taken up through its
stud, as it (the spring or rod) expands with an increased temperature, and it
will be let out as it contracts with a reduction of temperature.
The Invention is capable of being applied in a variety of ways, but it is
proposed generally to coil the combined laminæ of metal into a convolute
spiral form, and to attach the inner end of the coil firmly to one of the plates,
which hold the movement, and either to attach the end of the hair spring or
pendulum rod to the other end of the coil, or to a bar or lever against which
that end of the coil acts in such a manner as to cause the said bar or lever to-
move with the expansion and contraction of the coil produced by changes of
temperature, and so to take up or let out the spring or rod.
In the accompanying Drawing, Figs. 1, 2, and 3 represent different modes
of applying the Invention to the hair spring of a watch; and Figs. 4 and 5
represent modes of applying it to the pendulum rod of a clock.
In Figs. 1, 2, and 3, A represents the potence plate; a, the balance; C, the
cock which receives the outer pivot of the staff of the balance; and b, the hair
spring. The inner end of the coil of the hair spring, in all these examples of
the Invention, is connected with the staff of the balance wheel in the usual
manner, but the outer end, or, as it is generally termed, the "spare" end,
instead of being secured in the usual manner to a fixed stud secured in the
potence plate, is represented in Fig. 1 as being attached securely to a stud d;
carried by the arm c, which is formed by the extension of the outer extremity
of what is termed the "compensating coil" B. D is the regulator, applied
and furnished with curb pins e, e, to receive the outer coil of the hair spring in
the usual manner. The compensating coil B and its arm c are made of a strip
of brass and a strip of steel, united by soldering, brazing, or other means, the
steel being on the outside of the coil, as shown by the Drawing, in which the
steel is tinted blue, and the brass yellow. The inner extremity of the coil is
firmly secured by a screw f to a stud that is secured in the potence plate A,
but the outer extremity, and its arm c, are left perfectly free. The effect of an
increase of temperature is to expand or open the coil and raise the arm c in
an upward direction from the position represented in Fig. 1, and also to
produce a flexure of the arm c in a similar direction, and so to draw the hair
spring up through the curb pins e, e, and reduce its active length, and thus to
compensate for the expansion of the spring and the balance, and the effect of

page_text: a reduction of temperature is, of course, precisely the reverse. To obtain the
required degree of compensation an arm E of steel is secured by means of the
screw to the same stud as the compensating coil, and this arm contains a
small slot i to admit a screw h, which may be screwed into one of a number of
small tapped holes g. 9, provided in the coil. By screwing this screw h into
any one of these holes, so as to clamp the coil tightly against the arm E, while
the arm is secured by the screw f, all that portion of the coil between its inner
extremity and the screw h.is rendered inoperative on the arm c, and hence, by
changing the position of the arm E, and moving the screw to one of the holes
9, 9, further from the inner extremity of the coil, a less degree of compensation
is obtained, and by moving the arm and screw to another of the holes the
opposite effect is produced. Many other modes of checking the action of a
portion of the compensating coil on the hair spring may be used. The
regulator D operates in the usual manner.
The mode of applying the Invention represented in Fig. 2 differs from that
represented in Fig. 1, in having the outer or spare end of the coil attached by
the stud d to one end of a bar 1, whose other end is secured by a screw k to a
small plate F that is secured by screws j, j, to the potence plate; it also differs
in having a compensating coil B' applied so that its outer extremity presses
against the bar . This compensating coil is like that represented in Fig. 1,
except that its outer extremity is not continued to so great a length in the
form of an arm. The inner extremity of the coil is secured by a screw f to a
stud, which is fast in the plate F, and its outer extremity is made of V or
knife-edge form, to enter a notch in the bar l. This bar must be made suffi-
ciently elastic to keep bearing upon the compensating coil, notwithstanding the
expansion and contraction of the latter. The effect of the expansion of the
compensating coil is to move the bar upward from the position shown in
Fig. 2, and make it take up the hair spring through its curb pins e, e, and the
contraction of the coil permits the bar to spring in the opposite direction to
let out the spring. The degree of compensation in this example of the Inven-
tion is regulated by a screw m, which screws into one of a number of tapped
holes n, n, in the edge of the plate F. The head of this screw m is made to
press upon the bar l, and confine it to the plate F at a greater or less distance
from the screw k, according to which of the holes n, n, the screw m is placed
in. The degree of compensation is greater the nearer the screw m is applied
to the screw k, or the farther from the stud d. The bar / may be of one kind
of metal, in which case its action is merely that of a lever; or it may be a
compound bar, made of combined laminae of two kinds of metal, as represented,

page_text: and in the latter case the flexure of the bar, produced by changes of tempera-
ture, aids the coil in effecting compensation for the expansion of the spring and
balance.
In the example shown in Fig. 3 the coil is dispensed with, and a com-
pensating bar l', composed of laminæ of brass and steel, like that shown in
Fig. 2, and above described, and applied in the same manner, is made use of
to effect the whole amount of compensation. The degree of compensation in
this example is regulated by a screw m, and a number of tapped holes n, n, in
the plate F, which holds the bar in the same manner as described with
reference to Fig. 2, the screw m rendering a greater or less portion of the
bar operative on the hair spring, according as it is further from or nearer to
the stud d, which attaches the hair spring to the bar, and so compensating
more or less. The bar l' may be nearly straight, or of any curved or of a
reflex form.
There are many other forms in which the compensator may be constructed
for application to watches and other timekeepers governed by balances; but
it is generally preferable to make it in the form of a coil, as illustrated by
Figs. 1 and 2, for the reason that by it as long a hair spring as is desirable
may be used. Experiment seems to show it to be desirable to have the length
of the combined laminæ of steel or brass equal to about half the length of the
hair spring, except when levers are employed to multiply their effect; and the
greatest length that can be embraced in a bar like 7, would require a very
short and hard hair spring. Care should be taken that the parts of the com-
pensation are stiff enough to prevent their yielding perceptibly to the effect of
vibration of the hair spring and balance.
a is the pen-
In Fig. 4, A represents the back plate of a clock movement.
dulum rod; and 6 the slit horizontal stud, in which the thin flexible upper
portion of the rod fits. This stud, at the bottom of which is the axis of oscil-
lation of the pendulum, is fixed, as in the clocks in common use; but the rod,
instead of being suspended from this stud is suspended above it from the
outer extremity of a compound compensating coil B substantially like that
represented in Fig. 1, and before described; the coil B having its inner extre-
mity secured firmly to the plate A, and being so arranged and applied that as
the coil expands or opens with an increase of temperature it takes up the rod
a through the stud b, and as it contracts or closes with a reduction of tem-
perature it lets out the rod, and so controls the active length of the rod in such
a manner as to compensate for the expansion and contraction of the pendulum.
The degree of compensation effected by this coil may be regulated by a similar

page_text: contrivance to that illustrated in Fig. 1 for the same purpose, and herein-before
described.
In the example of the application of the Invention to clocks represented in
Fig. 5, the stud b is fixed in the plate A, as before described; but the rod a,
instead of being suspended directly from a compensating coil is suspended from
a lever C, which works on a fixed fulcrum c secured in the plate A, and rests
upon the outer extremity of the compensating coil B. The expansion and
contraction of the coil causes the rise and fall of the lever, and so causes the
pendulum rod to be taken up and let out through the stud 6 to compensate for
the expansion and contraction of the pendulum. In this application of the
coil the degree of compensation may be regulated by the use of a moveable
piece p attached to the end of the coil by a screw r passing through a slot in
the piece p, and screwing into the terminal portion of the coil. By moving
this piece toward the pendulum the degree of compensation is diminished, and
vice versa. The lever C may be a simple bar, or be composed of lamina of
brass and steel, so applied that by its flexure produced by changes of tem-
perature, it may aid the coil in its action. The length of the laminae of brass
and steel in the application of the Invention to pendulums may be equal to
about half the length of the pendulum rod when the principle of leverage is
not employed, but when a lever is used to multiply the movement effected by
the laminæ, their length may be correspondingly diminished. Instead of the
combined laminæ of brass and steel, combined laininæ of other metals, as silver
and platinum, which expand and contract differently with variations of tem-
perature, may be applied either to clocks or watches in any of the modes
herein described. Instead of a circular coil like those represented in Figs. 1,
2, 4, and 5, an angular coil, like that represented in Fig. 6, may be used in
combination, either with the hair spring or pendulum rod, and I would observe
that the brass may be applied outside of the steel in the coil instead of inside,
as described above, if preferred.
Having now described this Invention of Certain Improvements in Obtain-
ing Compensation for the Effects of Changes of Temperature in Timekeepers,
and having explained the manner of carrying the same into effect, as com-
municated to me by my foreign correspondent, I desire it to be distinctly
understood that I do not confine myself to the precise details herein described,
as such may be varied or modified without departing from the principle of
action thereof, and I do not confine myself to the strict figure or form of any
part of the apparatus herein described; but I claim as the Invention secured
to me by Letters Patent, as aforesaid,―

page_text: 1st, controlling the active length of the pendulum spring or "hair spring"
of a watch or other timekeeper, governed by a balance wheel by means of
combined laminæ of different metals, so applied to act upon the end of the
spring which has been usually fixed, that by an increase or diminution of tem-
perature the said spring will be caused to be taken up or let out through the
curb pins or their equivalent, and so to compensate for the expansion and
contraction of the said spring and the balance, as herein described.
2nd, controlling the active length of the pendulum rod of a clock by means
of combined laminæ of different metals so applied to act upon its upper end,
that by an increase or diminution of temperature the said rod will be caused
to be taken up or let down through the fixed stud b, or its equivalent, and so
to compensate for the expansion and contraction of the pendulum, as herein
described.
In witness whereof, I, the said William Edward Newton, have hereunto
set my hand and seal, this Nineteenth day of May, in the year of our
Lord One thousand eight hundred and sixty.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)