Abstract: A headrest device, intended for a chair, a seat or the like having a substantially vertical backrest, has an attachment part (1), by means of which it is to be attached to the backrest, and a headrest (6), which is mounted on the attachment part (1). The headrest (6) is mounted on the attachment part (1) by means of two link arms (7, 8), which at one end are connected, pivotally about a substantially vertical pivot axis, to the attachment part (1) and which at the other end are connected, hingedly about a substantially vertical axis, to a respective nut element (15, 16). The nut elements (15,16) are threadingly engaged with a substantially horizontal screw (23), which is turnably attached to the headrest (6) and which is arranged, in turning, to synchronously displace the nut elements (15, 16) in opposite directions along the screw (23) and thereby to pivot the link arms (7, 8) about their pivot axes to change the horizontal distance of the headrest (6) from the attachment part (1).

Abstract: An armrest device for an office chair comprises a fastening element (6) intended to be fixed to the chair beside the seat (4). The-device further includes an armrest (7, 8, 9, 20) which is connected to the fastening element (6) and has a vertical column (7) so connected to the fastening element as to be rotatable about its longitudinal axis, a horizontal rear supporting bar (8) connected to the column, and a front supporting bar (9) carrying a forearm rest (20), on which the user's forearm is to rest, and being telescopically displaceable in relation to the rear supporting bar (8) in order to form an armrest that can be lengthened and shortened as desired. The rear supporting bar (8) is so mounted on the column (7) as to be pivotable about a horizontal transverse axis (10).

Abstract: A device for releasably locking, in a tubular first member (1), a second member (2) which is displaceable in the first member, has a slide (6) mounted on the first member. A driver pin (7) on the second member <2) extends through a slot (4) in the first member and through a hole in the slide to entrain the slide in the displacement of the second member. A spring (9) urges an operazing lever (8) rotatably mounted on the driver pin (7), towards the slide (6). The slide has cam means (10) cooperating in such a manner with the operating lever (8) that this lever, when being rotated from a free position to a locking position, is urged out from the slide against the action of the spring (9), such that the spring urges the driver pin (7) outwardly so as to resiliently urge the second member (2) against the first member (1) which is thus clamped between the slide (6) and the second member (2), whereby to lock the latter in its position of displacement.