Improvements in the Method of and Means for Automatically Regulating Arc-lamps and other Electrical Apparatus.
Year: 1896

page_text: Date of Application, 24th July. 1896-Accepted, 31st Oct., 1896
COMPLETE SPECIFICATION.
Improvements in the Method of and Means for Automatically
Regulating Arc-lamps and other Electrical Apparatus.
I, WILLEM DE GRAAFF of Delft, Holland, Electrical 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 improvements in the method of and means for automatically regulating
electrical apparatus is primarily intended for use with arc-lamps, but is applicable
to any analogous purpose.
The irregularity of attraction exerted by a solenoid or electric magnet upon an
iron core can be corrected in some forms of arc and other lamps and apparatus by
giving a conical shape to the core. Fig. 1 represents in diagram a differential
lamp based upon the principle just mentioned where the cores kand (in the case
of the currents in the solenoids S' and S' having the same normal force) effect
(under all circumstances) an equal, but contrary rotary momemturn on the disc N
turning round the spindle W, because the attraction and the leverage are always
equal and therefore the equilibrium is maintained.
A similar action to that just mentioned is secured in the regulating apparatus
which is the subject matter of this invention, the essential feature being a
peculiarly shaped non circular disc.
In the diagram Fig. 2A, K' represents an iron core acted on by a current flowing
through the coil S'. The core K is suspended from a flexible metallic belt,
chain, link or other equivalent p', laid around the periphery of the circular
disc R and fixed thereon at s'. On the spindle of the disc R is secured the
non-circular disc or snail A, on the periphery of which is also a metallic belt
chain, liul: or other equivalent fixed at s². A weight pa is suspended from b³.
The force P by which the core K¹ is acted on at S' is not always the same, and
the disc A is therefore shaped in such manner that when the attraction P' increases,
the arm of the lever of the weight P is likewise extended and vice versa, equilibrium
being thus maintained. When therefore, the current in the coil S' is of the
normal intensity, the formula of equilibrium throughout the coil will be
p¹ p' = p² p².
When the intensity of the current is altered by reason of the consumption of
the carbons, the spindle W will revolve, when as is shown, for example, in Fig. 1,
the carbons will be brought into such position that the intensity of the current
will become normal and equilibrium again be established. In the instance just
mentioned, a gradual and continuous feed is given to the carbons as in the lamps
represented in Fig. 1.
Fig. 2 shows the iron core K¹ as operated by means of a rack and pinion R
acting on the spindle W, the other arrangements being similar to those of
Fig. 24.
Instead of employing a constant force P2 exerted by a weight, the attraction P¹
may be opposed by the varying force of a spring or the attraction on a second
core, or by other suitable means. The shape of the disc A is accordingly altered
so that in every position of the core P¹ p₁ = P³ p³.
In Fig. 3. Pacts upon the disc A. The arms p₁ of the lever are inversely
proportional to the values of P' when the opposing force p³ is constant. P* need
not, however. be constant in this case.

page_text: In Fig. 4, P and P cause the rotation of two non-circular discs A' and A
which in Figs. 4B and 4° are transformed into a disc A.
Ppl and P2 p² when normal need not be constant in every position so long
as PP p².
In the regulating apparatus represented in Figs. 5A 5B and 5", the non-circular
disc A acts as a kind of correcting disc to the third force P3 (which may be a
spring, weight or other contrivance) for the purpose of neutralizing the difference
between P and P2.
In Fig. 4 is shown a "snail "-like shaped disc A which permits the repeated
rotation of the spindle W.
Only a few of many possible modifications or arrangements have been shown in
the figures and I do not confine myself to those particular arrangements as I may
use any combination of them or their variations.
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. For the purpose of correcting the irregularity of magnetic attraction in
electrical apparatus in general and in arc-lamps in particular the application and
use of non-circular discs substantially in the manners (or any combination thereof)
described in the above specification and exemplified in the accompanying
drawings.
2. The improved method of and means for automatically regulating arc-lamps
and other electrical apparatus, the said method and means being provided for and
operating substantially as described in the accompanying specification and
exemplified in the accompanying drawings.
Dated this 21st day of July 1896.
HUGHES & YOUNG,
23, Coleman Street, London, E.C., Agents for the Applicant.