How does an Electric Bell use the Motor Effect?

[SSSingh]

I need help in explaining how electric bell uses motor effect.

 

[lekh2003]

I have a gut feeling this is for homework, is it? If so please post in the homework section and some attempt at the question instead of simply requesting an answer.

Also, what don't you understand about the motor effect in an electric bell? What part doesn't make sense.

 

[SSSingh]

I have a gut feeling this is for homework, is it? If so please post in the homework section and some attempt at the question instead of simply requesting an answer.

Also, what don't you understand about the motor effect in an electric bell? What part doesn't make sense.

This is not homework, i am new to this topic, and i am learning about the motor effect, what i understand about it is that a current carrying conductor produces a magnetic field. It is when the current carrying conductor interacts with an external magnetic field whicu produces a force. In this situation for an Electric bell there are no external magnets and it uses electromagnets, this is conufusing me and i don't exactly know how to write about the motor effect in the electric bell.

 

[lekh2003]

Ok, an electric bell works somewhat like a relay in this situation. You might want to look at this website: http://www.bbc.co.uk/schools/gcsebi...ng_things_moving/the_motor_effect/revision/2/

I found this quote which seems helpful:

1. When the current flows through the circuit, the electromagnet makes a magnetic field.
2. The electromagnet attracts the springy metal arm.
3. The arm hits the gong, which makes a sound.
4. The circuit is broken now the arm is out of position.
5. The electromagnet is turned off and the springy metal arm moves back.
6. The circuit is complete again.
   

The cycle repeats as long as the switch is closed.

Let me know if this was what you were looking for.

 

[Nik_2213]

This 'relay' design often produces a lot of RF interference, so a 'backlash catcher' diode may be added across the coil. It would be essential if you go to next step and use an 'astable' flip-flop or other pulse generator to drive the bell's hammer.

FWIW, one of our former 'ringers' held no bell, just a tiny loud-speaker and a 'playback' chip. Its timing components aged until, instead of a piercing 'DING-DONG', it went 'dunnnng-bonnng, dunnnng-bonnng' and was hastily replaced...

I've seen an old, 'industrial strength' bell that hid a tiny electric motor and two small 'flails'. Do not be stood near when that sounded off...