A New or Improved Method of and Apparatus for Storing Energy in Small Mechanical Accumulators.
Year: 1888

page_text: Date of Application, 31st Dec., 1888
Complete Specification Left, 30th Sept., 1889-Accepted, 23rd Nov., 1889
PROVISIONAL SPECIFICATION. .
A New or Improved Method of and Apparatus for Storing Energy in
Small Mechanical Accumulators.
I, JAMES GRIEVE LORRAIN, of Norfolk House, Victoria Embankment, London, W.C.,
Consulting Engineer, do hereby declare the nature of this invention to be as
follows
My invention relates to a new or improved method of an apparatus for storing
energy in small mechanical accumulators such for example as springs or weights.
The principle of my invention lies in the employment of the expansion produced in
a metallic conductor by the heating of the same through the resistance which it offers
to the passage of an electric current through it, the said expansion being utilised to
store energy in the mechanical accumulator (as by winding up a spring or raising
weight) through the medium of any suitable form of mechanical transmitting
mechanism.
a
I may obtain the current necessary to heat the conductor from any suitable source
or reservoir of electrical energy and I may determine its passage through the said
conductor by means of any suitable form of contact or circuit closing dovice this
latter being conveniently actuated or driven by the said mechanical accumulator.
I may employ a detent for the purpose of limiting or controlling the movement
produced by the said expansion.
My invention is specially applicable to winding up, the springs or weights
serving to drive clocks, advertising machines, musical boxes, mechanical toys, and the
like.
Dated this 31st day of December 1888.
J. G. LORRAIN.
COMPLETE SPECIFICATION.
A New or Improved Method of and Apparatus for Storing Energy in
Small Mechanical Accumulators.
I, JAMES GRIEVE LORRAIN, of Norfolk House, Victoria Embankment, London W.C.,
Consulting 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 a new or improved method of and apparatus for storing
energy in small mechanical accumulators such for example as springs or weights.
The principal of my invention lies in the employment of the expansion produced
in a metallic conductor by the heating of the same through the resistance which it
offers to the passage of an electric currrent through it, the said expansion being used
to store energy in the mechanical accumulator (as by winding up a spring or raising
a weight) through the medium of any suitable form of mechanical transmitting
mechanism.
I may obtain the current necessary to heat the conductor from any suitable source
or reservoir of electrical energy and I may determine its passage through the said
conductor by means of any suitable form of contact or circuit closing device this
latter being conveniently actuated or driven by the said mechanical accumulator.
I may employ a detent for the purpose of limiting or controlling the movement
produced by the said expansion.
My invention is specially applicable to winding up the springs or weights
serving to drive clocks, advertising machines, musical boxes, mechanical toys and
the lil-

page_text: Having thus described in general terms the nature and object of my invention I
shall now proceed to describe in what manner it is to be or may be performed or
carried into effect and for this purpose I shall describe by way of a type or example
one way of performing my invention. In order that such description of the type or
example which I have selected for mention herein may be more readily understood I
have annexed hereto a sheet of drawings illustrating the essential parts of my invention
as applied to the said type or example.
The accompanying figure serves to illustrato a convenient method of and combina-
tion of devices for carrying my invention into effect in the case of a clock the energy
being in this case stored up in the driving spring and the result being to convert the
ordinary form of clock shown into an automatic or self-winding one.
The figure is
a view of the clock as seen from behind.
In this figure A represents the winding wheel, that is to say the first of the train of
wheels through which power is transmitted to the spring-barrel to wind up, or in
other words store energy in, the driving spring. B is a thin metal wire rigidly
fixed at one end to the cock or terminal plate C whilst its other end is attached to the
weighted lever D. This lever turns freely on the arbor a on which the winding
wheel is rigidly mounted and bears the click or pawl E which gears into the teeth of
the ratchet wheel El which like A is also rigidly mounted on the arbor a¹.
The action of the parts just mentioned is as follows. The parts are connected up
and an electric current is transmitted through them at intervals for the purpose of
winding up the driving spring. In the figure I have shown the course of the current
as being from one pole of the battery to C then through B and part of D to and
thence by the contact to the other pole of the battery. Let us now assume that a
current is transmitted. In passing through B which is of such material and so thin
as to offer a considerable resistance the current raises the temperature of B and so
causes it to expand. This expansion of B causes the weighted lever D to descend
and the pawl E to engage with the teeth of the ratchet wheel H and carry the latter
round through a part of a revolution. The current ceasing now to be passed the
wire B will cool and in cooling will shrink so as to bring the lever D back into its
normal position as shown in the figure whilst the click G will prevent any backward
movement of the ratchet wheel H. With the backward movement of the lever D
the paw! E will ride loose over the teeth of HI and the parts will again be in their
normal position and ready to go through a similar cycle of movements at the next
transmission of the electric current.
If the parts have been very carefully constructed and adjusted with great nicety
the click G may be dispensed with but I do not recommend this as the click is always
a useful safeguard.
If care be taken to transmit only the proper amount of current and for the proper
time then the spring will be wound up to the proper amount each time the current
passes, but inasmuch as in practice batteries weaken with lapse of tiine and the load
increases as the bearings of the wheels get dirty the current would require to be
altered accordingly, I prefer instead of adapting the current to suit the altered
circumstances after each change to adopt controlling devices so that a definite amount
of movement shall always take place without reference to the exact condition of the
current. This definite amount of movement I secure by means of the detent F (in
this case shown as a set-screw) which limits or stops the descent of D after a definite
amount of movement has taken place and this quite irrespective of the amount of
expansion and of current, but always provided that the current be sufficient to cause
expansion until the detent F is reached by the lever. Any margin of current beyond
this amount will produce no further winding up of the spring. As a further safeguard
for the same purpose 1 generally employ a second detent which may conveniently
consist of a pin J. The function of this detent is to limit the amount of winding up
of the spring to the required amount by ensuring that in the backward movement of
the pawl to its normal position it shall not take too large a feed as it is termed that
is to say not come back so far as to engage a tooth of the ratchet wheel further back
than that tooth which when moved forward to the proper limit will cause the proper
"

page_text: amount of winding up of the driving spring. By this means also the action of the
clock is protected from any error due to variation of external temperature for it will
be readily seen that a fall of temperature when the current is not passing would
but for this detent J cause such a contraction of the wire B as to cause the pawl to
take a larger feed at the next transmission of the current and so produce a greater
mount of winding up of the spring than is desired.
It will be seen that at each transmission of the electro current a definite
movement of the expanding conductor takes place and that this imparts a definite
amount of movement through the train of wheels to the spring-barrel. In
practice I find it convenient to transmit the current from the battery or other
source or reservoir of electrical energy for a period of a second every one and
a half minutes and I adopt a train of wheels in accordance with this so that
the driving spring is wound up to the required amount at cach transmission.
The dimensions of the various parts hereinbefore described vary with the size
of the clock and the power required to wind it. In the case of an ordinary clock
as.inade with a dial about 8 inches in diameter a platinum wire of about 2 mils.
diameter and about 6 feet long will give good results. Sucli a wire may be heated by
a current of about to 1 ampère. The weight of or on the lever should be but little
in excess of what is required to wind the spring. The position of attachment of the
wire to the lever may be varied to suit the conditions of working. Thus if a large
current be supplied a shorter and thicker wire attached closer to the fulcrum may be
used but it should be borne in mind that the thicker the wire the fewer must be the
transmissions of the current within a given time or the shorter will be the amount of
movement of the wire at each transmission as a thick wire necessarily takes longer to
cool and contract than a thin one.
The clock case need not be made of great length to accommodate the wire. It may
be of ordinary form with a tube to contain the wire standing up from it. Or the
wire instead of being straight may pass over pulleys of non-conducting material so as
to be bent coiled or otherwise arranged in small compass.
In the type or example of my invention which I have described it is the expansion
of the wire which enables the weight to do the actual work of winding the spring.
As is self evident however the action might conveniently be reversed so that it would
be the contraction which would be used to wind the spring the expansion merely
serving to take the feed. In this case the position of F and of J would be
reversed as would the direction in which E and the teeth of H point, and the wire,
lever, detents and pawl would be arranged at the other side of the arbor a' from
that shown in the drawing. The lever would then need to be only sufficiently
weighted to take up the slack of the wire B as it is expanded or in other words
keep it taut.
The ratchet whee! and pawl arrangement for transmitting the movement of the
wire to the train of wheels leading to the spring-barrel is a convenient contrivance for
the purpose but equivalent devices will readily suggest themselves to mechanics.
same remark applies to the weighted lever.
The
The type or example which I have described illustrates the best means with which I
am acquainted for the carrying into effect of my invention. Other ways of utilising
the expansion of a conductor in accordance with my invention may be adopted if
desired and without departing from my invention. Many ways such for example as
the utilisation of the movement of a thermostatic band consisting of a compound strip
of two metals soldered together and having different co efficients of expansiou under
rise of temperature or the utilisation of the expansion of a metallic ring through
which passes a conical plunger so that the more the ring expands the further will the
plunger pass through it or the utilisation of the expansion of a mercury column are
obvious equivalents which would at once occur to the mind of any competent electrical
engineer.
In the figure it will be seen that the weight of or on the lever (a spring. would be
an obvious equivalent for the weight) takes up the movement of the conductor so
that the said movement can be utilised to produce the winding up of the spring,

page_text: I have shown how to perform my invention in the case of the driving spring of .a
clock. From this it will be readily seen by any one skilled in the art how my inven-
tion can be performed in the case of the driving weight of a clock. In the case of a
spring or weight serving to drive any other light piece of apparatus my invention
would be performed in the same way. Any competent Engineer will readily understand
from the foregoing specification how to carry my invention into effect in the case of
other small mechanical accumulators, such for example as minute hydraulic or com-
pressed air accumulators.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. The new or improved method of storing energy in small mechanical accumulators
consisting in utilising the expansion (of a conductor) produced by an electric current
substantially as set forth.
.
2. In apparatus for storing energy in small mechanical accumulators the employment
of an electrically expanded conductor substantially as set forth.
3. In apparatus for storing energy in small mechanical accumulators the com-
bination of an electrically expanded conductor and a weight or spring for taking
up the movement of the said conductor so that the said movement can be utilised.
4. In apparatus for storing energy in small mechanical accumulators actuated by an
electrically expanded conductor the means of securing a definite amount of movement
substantially as set forth.
5. In apparatus for storing energy in small mechanical accumulators the com-
bination of an electrically expanded conductor, a weighted lever, a pawl, a ratchet
wheel, and a train of wheels actuating the spring-barrel substantially as set forth.
Dated this 30th day of September 1889.
J. G. LORRAIN.