How does the CVT transmission work in the Micra, i10 and Kia Picanto?

We are looking at buying either the Micra K13, Hyundai i10 or Kia Picanto. We are interested in the CVT models and wondered what connects the gearbox to the engines in these. Are they torque converters or computer controlled clutches? If they are torque converters, do any of them lock at speed, as in the past I have been very impressed by the fuel efficiency of the old Morris Ital auto, which had such a locking device.

Asked on 28 April 2012 by ES, Upleadon, Glos

Answered by Honest John
The i10 and Picanto have the same 4-speed torque converter automatic transmission that will stay in fourth gear until the car needs third. The whirrings of the Micra CVT are explained in these two videos:
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