An electric bell functions using an electromagnet. When electric current is applied to the electromagnet, it produces a repetitive buzzing or clanging sound from the bell. The electric bell evolved from oscillating electromechanical devices developed after the 1823 invention of the electromagnet. Modern electric bell mechanisms originated from vibrating contact breakers in the 1830s-1840s that interrupted currents in induction coils. John Mirand added a clapper and gong to these devices in 1850 to create the standard electric bell design used for telegraphs.

1. Adrià Pérez, Amy Pedrosa &
Queralt Marquès

2. ELECTRIC BELL
An electric bell is a mechanical bell that (with rare
exceptions) functions by means of an electromagnet.
When an electric current is applied, it produces a
repetitive buzzing or clanging sound. Electric bells have
been widely used at railroad crossings, in telephones,
fire and burglar alarms, as school bells, doorbells, and
alarms in industrial plants, but they are now being widely
replaced with electronic sounders

3. History
The interrupter bell evolved from various
oscillating electromechanical mechanisms
which were devised following the invention
of the electromagnet by William Sturgeon in 1823.
One of the first was the oscillating electric wire invented
by James Marsh in 1824.This consisted of a wire pendulum dipping
into a mercury trough, suspended between the poles of an
electromagnet. When current was passed through the wire, the
force of the magnet made the wire swing sideways, out of the
mercury, which broke the current to the magnet, so the wire fell
back. The modern electric bell mechanism had its origin in vibrating
contact breaker or interrupter mechanisms devised to break the
primary current in induction coils. Vibrating hammer interrupters
were invented by Johann Philipp Wagner (1839) and Christian Ernst
Neeff (1847), and was developed into a buzzer by Froment
(1847).John Mirand around 1850 added a clapper and gong to
make the standard electric bell for use as a telegraph sounder.
Other types were invented around that time by Siemens and Halske
and by Lippens.The polarized (permanent magnet) bell used in
telephones, which appeared about 1860,had its beginning in the

4. Haw does the battery work
• An electric bell contains an electromagnet, consisting of
coils of insulated wire wound round iron rods. When an
electric current flows through the coils, the rods become
magnetic and attract a piece of iron attached to a
clapper. The clapper hits the bell and makes it ring.

5. Agraïments
• Agraïm a en Jordi Barraca, que ens ha
ajudat a entendre aquest tema. I ens ha
ajudat amb els problemes que hem tingut
durant aquest tema.

6. Agraïments
• Agraïm a en Jordi Barraca, que ens ha
ajudat a entendre aquest tema. I ens ha
ajudat amb els problemes que hem tingut
durant aquest tema.