Abstract: A chair includes a base, a seat operably supported on the base for depth adjustment, and a back operably supported by an upright that extends from the base for recline. The back includes a structural back support, a rear cover covering a rear side of the back support, and a front/lower concave cover covering the upright between a rear of the seat and below the back support to provide a one-piece back and seat appearance. The concave cover defines a concavity shaped to receive a rear of the seat to facilitate depth adjustment, but so that the one-piece back and seat appearance is maintained. The concave cover further includes upwardly extending tabs that engage a lower marginal edge of the back support to facilitate assembly.

Abstract: A chair includes a base, a seat operably supported on the base for depth adjustment, and a back operably supported by an upright that extends from the base for recline. The back includes a structural back support, a rear cover covering a rear side of the back support, and a front/lower concave cover covering the upright between a rear of the seat and below the back support to provide a one-piece back and seat appearance. The concave cover defines a concavity shaped to receive a rear of the seat to facilitate depth adjustment, but so that the one-piece back and seat appearance is maintained. The concave cover further includes upwardly extending tabs that engage a lower marginal edge of the back support to facilitate assembly.

Abstract: A chair including a seat support, a seat movably supported on the seat support for movement between a raised position permitting sliding depth adjustment of the seat and a lowered position preventing adjustment, and a detent device for securely holding the seat in the raised position while the seat is being slidable adjusted. A rack is formed integrally on or attached to the bottom of the seat shell. The detent device includes a seat support bracket attached to a top of a chair control, and a pair of moldings attached to opposite sides of the bracket. The moldings each include upwardly facing teeth for selectively engaging the racks to hold the seat in a selected, depth adjusted position. A resilient finger on each molding is adapted to engage a ridge on the seat shell for selectively holding the seat in either a raised position or in a lowered position.

Abstract: A structural support shell for a tilt-back chair has a back portion, a seat portion, and a flexible compression zone extending between the back and seat portions in an integrally molded, one-piece unit. The chair has a base with a recline control and pivoting recline control lever. The seat portion of the shell is fixed to the base and the back portion of the shell is fixed to the recline control lever. The flexible compression zone provides a simplified construction for an ergonomic chair design having an effective axis of rotation between the back portion and seat portion which is located above the seat portion, forward of the back portion, and generally adjacent to the hip joints of a seated user.