A chuck for clamping an article has a receiving portion including a receiving bore having a longitudinal axis L, and a radially inwardly facing contoured clamping and receiving inner surface. A clamping sleeve is accommodated in the receiving bore and is rotatable between a releasing position and a securing position. The contoured clamping and receiving surface has one or more clamping segments, each clamping segment having a ramp between a trough and a crest, a second ramp between the crest and a depression, and a third ramp between the depression and the succeeding stop ridge. Rotating the clamping sleeve within the receiving bore causes one or more rollers associated with each clamping segment to cooperate with the contoured clamping surface to effect the releasing and the securing of the article.
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