New or Improved Alarm Apparatus for Steam Boilers.
Year: 1899

page_text: Date of Application, 25th Mar., 1899-Accepted, 29th Apr., 1899
COMPLETE SPECIFICATION.
New or Improved Alarm Apparatus for Steam Boilers.
I, ELIAS ANDERSEN, of Koagger, North Schleswig in the Empire of Germany,
Farmer, 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 :-
This invention consists of an alarm apparatus for steam generators, which gives
notice by means of an electrical signal, when the water level in the steam boiler is too
high or too low. Boiler explosions, especially those which occur from the water
level being too low, are hereby prevented, as when the water level is either too high
or too low a bell or alarm is immediately brought into action.
Figure 1 of the accompanying drawings illustrates my improved apparatus fitted
on the boiler with the contact. connections in the water gauge, Figure 2 a similar
view with outside contact connection, Figure 3 the contact connection brought abɔnt
by a system of levers.
The apparatus in Figure 1 consists of a U-shaped piece of tube screwed into the
boiler, the longer piece of which tube can be formed by the gauge glass a the lower
part of which is in permanent communication with the water in the boiler. is a
float which rests continually on the water in the glass a at the same level as that of
the water in the boiler. To the top and bottom of this float are attached small
contact plates by which the two poles e e¹ or ff are brought into contact when
the level of the water in the boiler is too low or too high.
Figure 2 represents an apparatus with external contacts. The tube a is, in this
case, inade of metal, as the level of water in the boiler is indicated by the position of
a rod c which passes through the bottom of the tube as shewn and is attached to a
float b. In this case the cylinder a has a larger diameter, in order to enable the rod c
to overcome the friction caused by its passage through the bottom of the tube. The
poles e eland are attached to a bracket 7 and the contact is made by means of the
fork c on the rod c when the water level is too low or too high.
I
Figure 3 shows a third application of the apparatus, in which a float b is also used,
but in which the alarm mechanism is put into action by a system of levers. A float b
inside the boiler gives motion to a shaft i by means of a lever h. The shaft i passes
steam-tight through the shell of the boiler. On this shaft there is also attached
outside the boiler a lever : which effects the contact of the poles e e¹ and ƒƒ' when
the water level is too low or too high. The action of the waves of boiling water causes
the float to move up and down and it might happen that the bell ringing mechanism
would be set in action before the dangerous level had been reached. To obviate this,
springs are provided on each side of the lever k and serve the purpose of stopping
the bobbing up and down of the float. Only after overcoming the resistance of the
springs can the lever effect the contact between the two poles e e¹ or j¹ and
thereby set in action the bell-ringing mechanism.
In the apparatus illustrated in Figures 1 and 2 the up and down motion of the
float, caused by the boiling of the water, will be reduced to a minimum by the
employment of the tube a, and hence no springs are needed for the float. The action

page_text: of the apparatus which can be readily seen from the drawing shows clearly in what a
practical and certain manner the same must work in every arrangement of boiler.
It is obvious that the application of the apparatus to existing steam boilers is
extremely simple, that the cost of such an apparatus will be very low and that it can
be used on every description of boiler.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
Electrical alarm apparatus for steam generators in which contact is effected between
poles e e¹ or ff¹ by the use of a float b which moves either in the boiler itself or in a
water gauge glass or vessel a and either effects the contact by means of contact
plates inside the water gauge glass and attached to the float b, by means of a
fork cattached to a rod c which is carried through and below the vessel a, or that
the bell-ringing mechanism is set in action by a lever to which motion is com-
inunicated by means of a shaft i from a float b to which a lever is attached, the
lever moving between springs intended to check the up and down movement of
the float b, all substantially as described with reference to the drawings.
Pated this 25th day of March 1899.
E. ANDERSEN.
Per W. H. Beck, Agent.
115, Cannon Street, London, E.C.,