appliance charging via induction?

[Nelson]

A japanese national sent me a "National" brand electric razor made in japan. All of the documentation is japanese (particular unit is not intended for sale outside japan) - and I think one particular feature is unusual. The unit has the inevitable charger base which plugs into regular 115VAC, but neither the charger nor razor have any exposed electrical contacts. The charging light on the razor energizes when the razor is placed on the charging base. Do you folks think it is charging via induction or..? I have never seen a nicad battery-equipped unit (unit says Ni-Cd) and charger apparatus with no direct electrical contacts.

 

[jbartos]

Suggestion: Notice that Japan has 50HZ or 60HZ power supplies available in their country depending where one stays. This needs to be checked since the battery charger would have to be changed for 60HZ or 50HZ depending where you stay.
The low voltage side that charges battery is considered safe if it meets some industry standards, e.g. UL (Underwriters Laboratories (in USA), IEC (International Electrotechnical Commission), EN (European Norms), CSA (Canadian Standards Association), Japanese Standards, etc.

 

[Nelson]

Well yes I remember that half of Japan is 50Hz and the other half is 60Hz. The specs in the owner's manual say "AC 100-240V, 50-60Hz". I thought that the most interesting feature of the unit was that there were no electrical contacts on either the razor or the battery charger. That seemed to be a new technique to me; but it may be commonplace. I don't know.

 

[jbartos]

Comments: The electric energy may be converted by the transformation based on mutual electromagnetic induction between conductors/coils. For example, if you install a conductor under a high voltage line, which is sufficiently long, and attach some heater to its ends, that heater will produce the heat. Similarly, if the portable part accepts electrical energy through the electromagnetic induction for its operation and battery charging then there is no need for any contacts between the base and portable part. However, this is not the only principle on which a device similar to the shaver may operate.