Window Sashes and the like.
Year: 1886

page_text: Window Sashes and the like.
I ALFRED JULIUS BOULT of 323 High Holborn in the. County of Middlesex,
Engineer do hereby declare the nature of this invention (a communication from
Reuben Clarke of Toronto, Canada, Machinist) and in what manner the same is
to be performed, to be particularly described and ascertained in and by the following
statement:
The object of the invention is to design a spring balance which will give forth a
power substantially of equal strength in all parts of its stroke; and it consists
essentially, in an arrangement of levers placed between the spring and the weight
or body to be balanced, so that increased power is secured by increased leverage as
the tension of the spring is increased, and decreased power by decreased leverage
as the tension of the spring is decreased.
Figure 1, represents the compensating spring balance applied to a window-sash,
the spring shown being a spiral one.
Figures 2, 3, 4 and 5 show alternative forms of balances adapted for different
styles of springs.
In order to illustrate this invention I show it applied to the support of a window-
sash, but of course it will be understood that the same style of balance may be
applied in any position where it is desirable to provide a balance for a movable
body, it being merely necessary to increase or decrease the dimensions of the
various parts in order to adapt it for any-desired purpose.
In the drawings, A, represents a window-sash, and B, the window sill.
C, are two arms pivotted on the bottom of the sash, A and also to the arms or
levers, D. These levers are pivoted at, a, and are connected to or acted upon by
the balance spring E.
Various forms of balance spring may be used. In the drawings I show five
different forms, merely to indicate that I do not confine myself to any particular
style of spring, as any kind of spring may be adapted to this invention without in
any way altering the principle involved in the said invention.
In the drawings, like letters of reference indicate corresponding parts in each
figure, and on reference to each it will be noticed that the elements correspondingly

page_text: lettered produce exactly the same result, although the movements and shapes of
corresponding parts are slightly different in each illustration shown, for instance in
Figure 1, the spring, E, is a spiral spring and the levers, D, are provided with
short arms, a, to hook into the loop-spindles, f, connected to and designed to
operate the spring, E. When the sash A is pushed down into the position in
which it is indicated in dotted lines in Figure, 1, the arm, C, and levers, D, assume
the position likewise indicated in dotted lines, and the spring, E, is drawn out, the
tension of the said spring being increased in proportion to the length it is extended,
and it will be seen that in order to compensate for this increased tension the
leverage directed on the said spring, E, by the levers, D, is increased in proportion
to the strain on the spring. In other words, the effective length of the lever is
gradually increased as they are pushed down into the position indicated by dotted
lines, and in this way the changing power of the spring is compensated by the
arrangement of levers connecting the said spring to the movable body it is designed
to balance.
In
an ellip I show the levers, D, acted upon by a curved spring supported by
.
In Figure, 3, I.show the levers, D, acted upon by a laminated elliptic spring.
In Figure, 4, I show the levers D, acted upon by curled springs; and in Figure, 5,
by spring plates.
As stated in the former part of this specification I show these various forms
simply to indicate that I do not wish to confine myself to any particular style of
spring, but I may state here that I think the arrangements shown in Figure, 1, will
generally be found the simplest and best.
'
Although I find it preferable. to employ a double set of levers, D, and a double
set of arms, C, it will be seen that the balance would act with only one arm, C, and
one lever, D, when actuated by a spring E.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is:
1. A compensating spring balance consisting of the arm, C, pivoted at one end to
the movable body, and at its other end to the pivoted lever, D, in combination
with the spring E, arranged to act on the lever, D, substantially as and for the
purpose specified.
2. A compensating spring balance consisting of the arms, C, pivoted at one end
to the movable body, and at their other ends to the pivoted levers, D, in combination
with a spring, E, arranged to act on the levers, D, substantially as and for the
purpose specified.
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Dated this 96th day of Febru 1986