Improvements in Electric and Magneto Bells and Apparatus to be used therewith.
Year: 1889

page_text: Date of Application, 31st Dec., 1889
Complete Specification Left, 30th Sept., 1890-Accepted, 13th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in Electric and Magneto Bells and Apparatus to be
used therewith.
We, HANS PETER FREDERIK JENSEN and JENS JENSEN both of 2 Gray's Inn Road
in the County of London Electrical Engineers do hereby declare the nature of this
invention to be as follows:-
The objects of these improvements are to improve and simplify the construction of
such apparatus and to cheapen the manufacture.
We form the armature of bells or indicators of a thin piece of iron or steel or both
suitably united, the upper end being made quite thin to form a spring and bent at
right angles and having an eye for passing the core shank through it and through the
top of the bell, one nut at the end of the shank serving to hold the armature, the
break spring, the insulating disc, the core and the bell together. The bottom end of
core is cut off square or sloping, and the lower end of the armature and of the break
spring are bent and continued down below it, thus rendering access to the break
spring easier than heretofore.
The break spring may be done away with altogether in a modified arrangement
where the spring end of the armature is fixed to the insulating disc and a platinum
wire inserted in the core protrudes slightly at the outer end of same, so that the
current is thereby short circuited each time the armature is attached and touches the
platinum, thus producing the required continuous sounding or trembling action.
as
In another form we fix the spring part of the armature to a disc of brass or
the like and provide the end of the armature with a thin disc which serves
an indicator flag. The armature operates against a pole piece at each end of the
electromagnet. The whole arrangement takes up very little space.
Sometimes we employ an additional armature to which is attached a disc or
equivalent device for indicating when the bell has rung, the electromagnet when
excited by a direct or alternating current imparting a trembling motion to both
armatures. The indicating armature is preferably placed at right angles to the one
operating the bell clapper.
We construct a simple form of drop indicator by mounting a flag disc on to the
end pole piece of the electromagnet, such disc having a radially struck slot and the
end of the armature being provided with a small pin which engages with the slot.
The latter is at one end formed with a notch or wider part for the armature pin
to hold the flag disc in the raised position as long as the circuit is broken, but
when the armature is attracted the armature pin is withdrawn from the notch and the
flag can then drop.
We form a simple and cheap combined flag and armature of one piece of stamped
out sheet iron bent up at right angles at each end, one such end part forming flag
and armature for one pole end of core, the other end part forming armature for the
other pole end of core, and a strip being bent off from the intermediate portion to
form the arm for the replacer rod to act against. We thus lessen the cost of
manufacture of annunciators and economize current. The same piece of stamped
out and bent metal can be used as a mere flag in connection with an independent
armature.
The forms described may be used either for bells or as annunciators or both and
may be fixed in or outside a bell or other sounding appliance. They may be used
in a manner similar to the indicators and bells ordinarily used or may be placed
round one or more gongs so as to serve the combined purpose of bell and
annunciator.
Electric bells of nearly every kind are sometimes accidentially or wilfully thrown

page_text: out of adjustment by reason of the break spring or the adjusting screw thereof
being tempered with or by forcibly bending the armature or the clapper. To
prevent this we sometimes enclose the mechanisin in a metal box suitably fastened or
we cover the base of the bell with a metal or other plate similarly mounted.
In order to actuate any one of two or more electric bells or annunciators by a
single push knob we fit the latter so as to slide but not turn in a socket which
is provided with a hand or marked line and is capable of turning round relatively to a
disc which is marked with two or more numbers corresponding to the respective bells
or annunciators.
The push knob has on its inner end a contact piece or arm which when the
socket with the knob is turned with the hand or marked line against any one of
the numbers can make electrical connection with and close the circuit of the bell or
annunciator in question. This form of push knob enables us within the compass of
an ordinary contact breaker to combine two or more such, taking up less space and
having a neater appearance. This is of especial advantage in rooms and where the
bells or annunciators, or both, are used in connection with a speaking tube.
In the Specification of Patent No. 4712 of 1882 is described an electric bell having
the clapper and shank or rod in one piece with and counterbalancing or thereabouts
the armature of an electro-magnet, which armature is attracted by pole pieces at
each end of the electro-magnet, and which is pin-jointed to the core of the electro-
magnet; being for that purpose formed with an oval eye embracing such core.
According to our invention we greatly cheapen and simplify the construction by
forming the clapper rod and armature out of a piece of iron of uniform thickness; by
preference by stamping it out of sheet iron having the thickness of the armature, and
we then twist the shank or root part of the armature round to an angle of
90 degrees.
-
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Electric and Magneto Bells and Apparatus to be
used therewith.
We, HANS PETER FREDERIK JENSEN and JENS JENSEN both of 2 Gray's Inn Road
in the County of London Electrical Engineers 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 :-
The objects of these improvements are to improve and simplify the construction and
use of such apparatus and to cheapen the manufacture, and especially of the apparatus
known as the Jensen electric bell and signal system described in the Specification of
Patents No. 471282, 611885 and 310688.
We form the armature of bells or indicators such for instance as shown in Figure 6
of No. 3106 of a thin piece of such a shape as to admit of using a make and break.
contact spring to greater advantage and of constructing a trembling bell possessing
the well known advantages of the Jensen bell while easier of adjustment.
Figure 1 of the accompanying drawings shews an armature in the form of a thin
piece of iron or steel, or both suitably united, the upper end B being made quite thin
to form a spring and bent at right angles and having an eye for passing the core
shank through it and through the top of the bell, one nut C at the end of the shank
serving to hold the armature, the break spring D with the insulating disc, E, the
core G and the bell F together. The bottom end of core G is cut off square or by
preference, sloping as shewn and the lower end A of the armature, and of the break
spring D are bent and continued down below it the upper part of the spring B forming
a polar extension of the electro-magnet X. By this construction we render access to
the break spring easier than heretofore.

page_text: Figure 1 shews a modification in which the electro-magnet ▲ 19 suspended in a
flat spring X the armature A being a fixture to the bell and either double
as shewn or single. The same arrangement that is to say making the magnet
movable and the armature a fixture may also be used in the other arrangements herein
described.
Figure 2 shews another form in which the armature spring B is fixed to a pro-
jecting pole B'.
Figure 3 shews another form of armature A which is hinged to a bracket or
bridge H fixed to the insulating disc E. The bracket H also carries a contact
spring D.
In Figures 4 and 5 the bobbin of the magnet X is used for supporting and
insulating the bracket H. Either end of bobbin may be used as
contact bracket H. The movement of the bell is prevented from
adjustment by being confined within a space, as shewn in Fig. 5.
hammer is regulated by means of the screw Y.
insulator for the
being put out of
The throw of the
In Figure 6 the armature A is arranged at the top, two electro-magnets being used
as an example, but two are also applicable in the other arrangements.
In Figure 7 the armature A is provided with a screw Y for regulating the spring r
described in Specification 47128. In Figure 6 the adjusting screw Y passes through
the bell itself.
In another form shown at Figure 8 in plan we fix the spring part A of the
armature to a disc E of brass or other non magnetic metal and provide the end of the
armature A with a thin disc I at right angles thereto which serves as an indicator
flag. This latter is arranged to be parallel with the glass of the case and is thus
plainly visible. The armature A operates against a pole piece extension M M' at
each end of the electro-magnet. The whole arrangement takes up much less space
than the pendulous indicators heretofore used. Also by the slanting position of the
bobbin we are enabled to get the flag parallel with the glass of the case.
indicator acts as single stroke bell and no insulation is required. It belongs to the
self replacing class of indicators and is very simple in construction and cheap.
Several of them may be placed round a gong so that the flag I strikes the same
when the armature A is attracted and it will vibrate some time after being
released.
This
According to a modification we fix the armature and make it rigid and mount
the electro-magnet on a spring in the same manner as described with reference to
Figure 1. The flag would then be fixed on the top of the magnet.
Figure 9 shews an improved form of polar extension M, which we make with a
slot as shewn so that it can be readily adjusted by merely loosening the screw which
serves to secure it to the core iron. By this means we increase the usefulness and
ensure more accurate adjustment.
We construct a simple form of drop indicator by mounting a flag disc I such as
shewn at Figure 15 on to the end pole piece M' Figure 8 of the electro-magnet on a
pivot at 13, such disc having a radially struck slot I¹ and the end of the armature
being provided with a small pin which engages with the slot. The latter is at one
end formed with a notch or wider part I for the armature pin to hold the flag disc in
the raised or horizontal position as long as the circuit is broken, but when the
armature is attracted the armature pin is withdrawn from the notch and the flag can
then drop, its heavier end overbalancing itself in the inclined position.
We form a simple and cheap flag for the kind of indicator described with reference
to Figure 8 of No. 611888 of one piece of stamped out sheet iron.
Figure 10 shews such a blank stamped out and then bent up at right angles across
the dotted lines shewn. The lug K2 serves as the replacement lug, and the edge K*
engages with the ratchet tooth of the armature as shewn in Figure 12. We some-
times use this stamping as combined armature and flag one end part forming flag
and armature for one end of magnet and the other forming armature for the other
pole as shewn in Figure 11. We thus lessen the cost of manufacture of annunciators
and economize current,

page_text: In Figures 13 and 14 the flag K with replacement stud K2 is mounted on one end
of the core iron and the armature A is fixed on the other arm of the horse shoe
magnet.
Electric bells of nearly every kind are sometimes accidentally or wilfully thrown
out of adjustment by reason of the break spring or the adjusting screw thereof being
tampered with or by forcibly bending the armature or the clapper. To prevent this
we sometimes enclose the mechanism in a metal box suitably fastened.
In Figure 7 already referred to we shew the movement enclosed in a metal
box Z.
Figure 16 shews another form of enclosed electric bell. The bridge or support V
to which the electro-magnet the contact maker and the bell itself are fixed is much
narrower than the bell and is hinged to a base W which normally forms a closure to
the underside of the bell, but so that when the bell requires adjustment this can be
done by unscrewing the screw X from the base W and raising the bridge V to the
position shewn but without detaching the bell from its support V; and the accidentally
moving the clapper out of its proper position or distance from the bell is prevented.
The support V may be united to the base W by lock and key. The bell may be of
the form here shewn (like Figures 7 and 8 of Specification 471282) or of any other
form. The bridge V instead of being hinged may be secured detachably or movably
to the base plate W by a hook, clip or catch of any suitable construction.
The aforesaid bells and indicators may be used as heretofore being placed one or
more of them on a board or in a box with the battery in any convenient place but in
order to prevent their being wrongly connected up and that especially when sent
abroad where it is at times difficult to obtain the qualified professional assistance for
installations we prefer to include in one case one or more dry cells already connected
up to the indicators so that all that is needed is to fix the wires to the terminals fixed
on the case. Any good dry or semidry battery may be used but we prefer the one
described in Specification 199883 and granulate the compound before filling up the
cell, while leaving a suitable opening for adding a little solution of some alkali or
saline salt or mineral acid as required.
In order to actuate any one of two or more electric bells or annunciators by a
single push knob we use the arrangement shewn in Figure 17 where the push knob L
is made with a lower square end or so as to slide but not turn in a socket which is
provided with a hand or marked line and is capable of turning round relatively to a
disc P which is marked with two or more numbers corresponding to the respective
bells or annunciators. The push knob L: has on its inner end a contact piece or arm Q
which when the socket O with the knob Lis turned with the hand or marked line
against any one of the numbers can make electrical connection with any one of the
corresponding contacts R and close the circuit of the bell or annunciator in question.
This form of push knob enables us within the compass of an ordinary contact breaker
to combine two or more such, taking up less space and having a neater appearance.
This is of especial advantage in rooms and where the bells or annunciators or both are
used in connection with a speaking tube.
In the Specification of Patent No. 4712 of 1882 is described with reference to
Sheet 2 of the drawings an electric bell having the clapper and shank or rod in one
piece with and counterbalancing or thereabouts the armature of an electro-magnet
which armature is attracted by pole pieces at each end of the electro-magnet and
which is pin-jointed to the core of the electro-magnet being for that purpose formed
with an oval eye embracing such core.
According to our present invention we greatly cheapen and simplify the construction
by forming the clapper rod and armature out of a piece of iron of uniform thickness
by preference by stamping it out of sheet iron having the thickness of the armature,
and we then twist the shank or root part of the armature round to an angle of 90°.
This enables us to use a thinner material than hitherto and yet obtain a sufficient body
for the rivet joint by which the armature is hinged to the magnet without in any way
lessening the durability or utility of the work. By this method we greatly refuce.
the cost of manufacture.

page_text: Figure 18 is plan view of a blank stamped out, the armature end A being of the
required width and the eye A of ample size to take a pin whereby it is jointed to the
magnet core, being passed through a slot formed therein while the hammer stem end
is of sufficient thickness. The blank is then given a twist as shewn in Figure 19 so
that the armature part A assumes the right form relatively to the eye, and can then
be bent into the required form to serve as armature and hammer stem as shewn in
Figure 4.
Figure 20 shews another form of blank which is suitable for the case that the core
passes through the armature. For this purpose the blank is formed with lugs or ears
which can be bent up as required to give the proper bearing for the rivet whereby it
is jointed to the core.
Figure 21 shews another form of stamped out or cast blank having the armature
part A formed with lugs Ax and which may be made of iron or brass. The soft iron
armature shewn in Figure 22 is formed with holes for the lugs A* to enter and to be
united thereto by rivetting over.
Figure 23 shews a blank made of wire bent into the required shape and flattened
at the place A2 where the joint pin passes through.
We sometimes utilize it for holding a piece of insulating material such as vulcanite
in which the contact screw is mounted. The aforesaid armatures are by preference
made of soft iron or they may be combined with soft iron.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is:
First. The improved construction of armature and contact spring and the fixing of
same to the same base, bell, or gong by means of one nut substantially as described
with reference to Figures 1, 2 and 3.
Second. The improved arrangements for regulating the contact spring substantially
as described with reference to Figures 1, 2, 3, 4, 5, 6 and 7.
Third. The improved construction of pole piece for facilitating adjustment sub-
stantially as described with reference to Figure 9.
Fourth. The improved construction of indicator having a slanting bobbin and
spring armature with a flag fixed at right angles thereto substantially as described
with reference to Figures 8 and 15.
Fifth. Constructing combined flag and armature and combined or double armature
in one piece from a stamped out blank which may also contain a replacer lug; sub-
stantially as described with reference to Figures 10, 11 and 12.
Sixth. An electro-magnet mounted on a spring in combination with one or two
stationary armatures substantially as described with reference to Figures 14 and 8.
Seventh. Enclosing in a casing the movement of an electric bell inside the dome of
the bell substantially as and for the purposes described with reference to Figures 7
and 16.
Eighth. In combination with bells and indicators one or more dry or semidry
battery cells charged as stated substantially as set forth.
Ninth. A push knob mounted in a socket so as to slide therein but not turn in
combination with an indicator disc said knob having a contact arm which can be
turned to contact with any one of a number of arms severally connected to electric
bells or indicators substantially as described with reference to Figure 17.
Tenth. The method of manufacturing armature and clapper stem substantially as
described with reference to Figures 18-23.
nated this 20th dox of S.
1000
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.