Headrest support structure of conveyance seat

摘要

A headrest support structure of a conveyance seat includes: an upper frame that is provided with a pair of fitting holes and that constitutes a back frame; and a pair of cylindrical headrest holders, each of which fits in one of the pair of fitting holes to be fixed to the upper frame. A transverse cross-section of a fitting portion of each headrest holder fitting in the corresponding fitting hole has an asymmetric shape about a fitting axis parallel to a fitting direction in which the headrest holder fits in the fitting hole, the transverse cross-section being a cross-section in a direction orthogonal to the fitting axis. The pair of fitting holes is formed such that each headrest holder is allowed to fit in only one of the pair of fitting holes provided at a position set as a fixing position of the headrest holder.

主权项

1. A headrest support structure of a conveyance seat, comprising:
an upper frame that is provided with a pair of fitting holes and that constitutes a back frame; and a pair of cylindrical headrest holders, each of which is configured to fit in each of the pair of fitting holes to be fixed to the upper frame, wherein a transverse cross-section of a fitting portion of each headrest holder configured to fit in each of the corresponding fitting holes has an asymmetric shape about a fitting axis parallel to a fitting direction in which the headrest holder fits in the fitting hole, the transverse cross-section being a cross-section in a direction orthogonal to the fitting axis, the pair of fitting holes are oriented differently relative to each other and when the asymmetric shapes of each headrest holder are oriented in a same initial position about the respective fitting axis of each headrest holder, the asymmetric shapes of each of the pair of headrest holders is configured to fit in one of the pair of fitting holes, and the asymmetric shapes of each of the pair of headrest holders is configured to fit in the other of the pair of fitting holes only when the pair of the headrest holders are at least one of:
inverted in a top-bottom direction of the conveyance seat with respect to the initial position; androtated about the fitting axis of the respective headrest holder with respect to the initial position.