Slow Striking Electric Bells.
Year: 1893

page_text: Date of Application, 5th Aug., 1893
Complete Specification Left, 5th May, 1894-Accepted, 5th Sept.,
1894
PROVISIONAL SPECIFICATION.
Slow Striking Electric Bells.
I HERMANN OPPENHEIMER Manager of The International Electric Co. of
55 Redcross Street in the City of London do hereby declare the nature of this
invention to be as follows:-
:-
In order to produce à stroke at larger intervals in electric bells, or so called
trembling bells, it is necessary that the automatic interruptions should not be
caused directly by the movement of the armature, but that the contact should be
interrupted by an intermediate mechanism. The length of such pause is regulated
by the inertia of the substance forming the parts of such intermediate mechanism.
The latter consists of a fly wheel M with pinion Z and rack S. They are actuated
by the movement of the armature, so that the rack S is thrown up when the
armature is receeding, thus revolving the fly wheel to the left. The weight of
the rack limits this movement, and when reaching the highest point, the rack falls
down by gravity, pushing against the lower part of the lever H Fig. 2, and the
contact spring F Fig. 2 respectively, thus interrupting contact C.
The armature
is then released, and the rack rebounds through the force of the spiral spring S.
According to the adjustment of such spiral spring, the rack will be raised more or
less high, and the strokes of the hammer will consequently be in quicker or
retarded intervals. It is necessary that the contact should be closed in whatever
position the armature may be, and the contact spring F (supported by the lever of
the armature H), must be so constructed that the small space a Fig. 2. between
rack and contact spring, created by the armature being attracted, is sufficient to
cause the first interruption of the contact, in consequence of which the rack
rebounds for the first time. The rack not being bodily connected to the armature,
the latter will be attracted as easily as in an ordinary bell. This advantage and
the fact that the contact is always closed, allows, by using an ordinary push
connected to the line, to produce distinct signals in the same manner as if the bell
were constructed as a single stroke bell.
Fig. 1. shows the bell in its normal condition; Fig. 2. at the moment the armature
is attracted for the first time.
Dated the 5th of August 1893.
COMPLETE SPECIFICATION.
Slow Striking Electric Bells.
1, HERMANN OPPENHEIMER of 55 Redcross Street, London, E.C. Electrical
3 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 :→
.
J4
In order to produce a stroke at larger intervals in electric bells, or so called
trembling bells, it is necessary that the automatic interruptions should not be
caused directly by the movement of the armature, but that the contact should be
interrupted by an intermediate mechanism. The length of such pause is regulated
by the inertia of the substance forming the parts of such intermediate mechanism.
D
j...

page_text: The latter, consists of a fly wheel M, with pinion Z, and rack S, (Provisional
drawing). They are actuated by the movement of the armature, so that the rack
S is thrown up when the armature is receding, having been attracted previously,
when a current was passing the electromagnets, thus revolving the fly wheel to the
left. The weight of the rack limits this movement, and when reaching the highest
point, the rack falls down by gravity, pushing against the lower part of the lever H,
Fig. 2, (Provisional drawing,) and the contact spring F, Fig. 2, (Provisional drawing,)
respectively, thus interrupting contact C. The armature is then released, and the
rack rebounds through the force of the spiral spring &, (Provisional drawing).
According to the adjustment of such spiral spring, the rack will be raised more or
less high, and the strokes of the hammer will consequently be in quicker or retarded
intervals. It is necessary that the contact should be closed in whatever position
the armature may be, and the contact spring F, (supported by the lever of the
armature H), must be so constructed, that the small space a, Fig. 2, (Provisional
drawing) between rack and contact spring, created by the armature being attracted,
is sufficient to cause the first interruption of the contact, in consequence of which
the rack rebounds for the first time. The rack not being bodily connected to the
armature, the latter will be attracted as easily as in an ordinary bell.
It can however be utilized not only as a slow striking bell, but also as a single
stroke bell or an ordinary. trembling. bell. For such purposes, 'I constructed the
bell in the following manner.
Having regard to the action of the bell to be worked as single stroke bell, I
have brought the pivot D, (Fig. 1 Complete drawing), of the armature A in such
close proximity to the electromagnets to produce a stroke of wide rangé even with
the slightest movement of the armature.
The circuit of the current which I show in Fig. 2, Complete drawing, is not
interrupted between the terminals E & R, and consequently when push No. 1 is
pressed,, only a single stroke of the hammer will follow.
When the bell is used for slow striking, it is now, not necessary that the current
should be closed during the long pauses. In order to attain this result 1 transfer
the contact C to the opposite part of the lever, and instead of the fixed contact
pillar, use the movable rack Z, as a contact piece.
The contact C. is in connection with that, part of the circuit as shown
in L. C. D. B. R. When the armature is attracted the rack Z is thrown up,
whereby the pinion is set revolving to the right. Rack & pinion are suitably.
suspended in a, frame, giving, where necessary, support to rack or pinion
respectively. The rack moves freely in the slotted part of said frame, and is at
its upper end, connected to L, by means of a flexible cord Fig. 1 & 2, (Complete"
drawing).
In consequence of the interruption at point C. the armature is released after the
first stroke, until the rack falls down again by gravity, and forms the contact anew
at Cwhereupon the second-stroke of the hammer takes place and so on.
The hammer necessarily will repeat these strokes, slowly following each other as
long as the push 2 is pressed.
Besides the contact C, I use another fixed contact pillar S, the same as is used
in ordinary trembling bells, which touches platinum point on spring F. attached
to armature.
L
...
On pressing the push 3, the current goes via U. S. F. D. B. R., and the bell
works as an ordinary trembling one, whereby the rack remains in a higher position
through the quick successive jerks at C, as the inertia of the pinion does not
allow the fall of the rack during the short intervals when the armature is
released.
2.
The construction of this universal bell is so arranged, that the parts which are
necessary for the safe working of the movement whiteford kind of signal..

page_text: 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. In slow striking bells as described the use and arrangement of a rack and
pinion acting upon such part of the lever of the armature which, when the armature
is attracted throws up the rack, and the further use of the rack as contact piece
for the self-interruption of the slow striking bell, substantially as described and
in the manner set forth.
2. The construction, simultaneous arrangement, and use of the slow striking bell
as an ordinary trembling bell by attaching to the same armature a second contact
spring F, making contact at the pillar S, substantially as described and in the
manner set forth.
3. The internal connecting up of this universal bell as shown in Fig. 2, which
demonstrates 3 different circuits with one common return, each circuit having a
different effect on the hammer, in such a manner that the bell when using the
circuit indicated by E. B. R.; L. C. E., and U. S. R, will work as single stroke
bell, as slow striking bell, and ordinary trembling bell respectively, substantially
as described and for the purpose set forth.
Dated this 5th day of May 1894.