Leggett & Platt, Inc.

Kenneth C Hybarger

Philip E Crossman

Bryan H Zeeuw

David A Young

LeRoy Bryan Johnson

A chair control mechanism is provided for use on a chair having a separate seat 14 and backrest 16 that move with respect to a base 12 of the chair. The mechanism 22 includes a housing 26 supported on the base, and brackets 28, 30 secured to the seat and backrest. The seat bracket 28 is supported on the housing for pivotal movement about a horizontally extending front pivot axis 68 between an upright position and a reclining position, and the front pivot axis is located adjacent the front end of the housing. The backrest bracket 30 is supported on the housing for pivotal movement about a horizontally extending rear pivot axis 80 that is located rearward of the front pivot axis. A mechanical linkage 70, 78 is connected between the brackets at a position spaced rearward of the rear pivot axis relative to the housing for transmitting pivoting movement between the brackets, and a spring assembly 32 is connected between the housing and the backrest bracket for biasing the seat and backrest toward the upright position.

Synchronized chair seat and backrest tilt control mechanism

A chair control mechanism is provided for use on a chair having a separate seat 14 and backrest 16 that move with respect to a base 12 of the chair. The mechanism 22 includes a housing 26 supported on the base, and brackets 28, 30 secured to the seat and backrest. The seat bracket 28 is supported on the housing for pivotal movement about a horizontally extending front pivot axis 68 between an upright position and a reclining position, and the front pivot axis is located adjacent the front end of the housing. The backrest bracket 30 is supported on the housing for pivotal movement about a horizontally extending rear pivot axis 80 that is located rearward of the front pivot axis. A mechanical linkage 70, 78 is connected between the brackets at a position spaced rearward of the rear pivot axis relative to the housing for transmitting pivoting movement between the brackets, and a spring assembly 32 is connected between the housing and the backrest bracket for biasing the seat and backrest toward the upright position. A forward travel-stop control assembly 38 is provided on the mechanism for adjusting the forward most position of the seat and backrest, as is a tilt control assembly 36 which permits the seat and backrest to be locked against tilting movement. The tilt control assembly 36 includes a locking plate 102 supported on the housing for relative translational movement between an extended position in which the locking plate is received in an aperture of the backrest bracket to lock the backrest bracket from further pivotal movement, and a retracted position removed from the aperture to allow further pivotal movement of the seat and backrest. A locking pawl 106 is supported on a lever 104 of the tilt assembly and engages the lock plate 102 to retract and extend the plate when the lever is rotated. In addition, a clutch is interposed between the actuating lever and the locking pawl for exerting a rotating force on the locking pawl to move the locking pawl from the second position when the actuating lever is rotated. The rotating force of the clutch is smaller than the friction force that is exerted on the locking plate when the pivoting force of the spring assembly 32 is exerted on the locking plate such that the locking plate can only be retracted when the friction force is reduced to a magnitude less than the rotating force.

A chair tilt mechanism incorporating a tilt stop and height adjustment mechanism on a single lever is disclosed. In addition, the component parts of the chair tilt mechanism can be formed by conventional stamping operations which allows for the standard components to be used for a wide variety of chair tilt applications. The chair tilt mechanism includes a housing mounted to the support spindle and rails mounted to the underside of a chair. The rails are pivotally mounted to the housing and a load bracket member is fixedly mounted to the rails. A tilt adjustment spring extends between the load bracket and the housing. A lever is received within the housing and is laterally movable within the housing to selectively engage a tilt lock and adjust the height of the chair.

Chair tilt and height adjustment mechanism

A low profile knee-tilt chair control for controlling biased tilting between a chair seat plate and a chair base plate of a pedestal base chair wherein the chair base plate is supported by a single vertical spindle at the rear of the base plate, and the chair seat plate pivots about a horizontal axis at the front of the base plate. The chair seat is biased to an at-rest position by a low profile, conical helical compression spring operable between the base plate and chair seat and located between the spindle and the horizontal pivot axis of the base plate. The low profile, conical helical compression spring is so mounted relative to the base plate and chair seat plate that the small coils of the compression spring may pass through the large coils during compression of the spring. The control is further characterized by a lockout for securing the chair seat plate against tilting relative to the base plate in either of two different, selectable, at-rest positions.

Growing community of inventors

Belding, MI, United States of America

Kenneth C Hybarger