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Ergonomic Office Chair

Product

Overview

The ergonomic office chair is a high-back task seat designed for full-shift use at a desk. It combines pneumatic height adjustment, a synchronized recline mechanism, a breathable mesh backrest, and four-way adjustable armrests so that the seat can be fitted to a wide range of body sizes. The chair is rated to a 136 kg occupant and conforms to BIFMA durability standards for commercial seating.

The chair resolves into seven major sub-assemblies. The Base Assembly carries the chair on five casters, the Pneumatic Gas Lift sets seat height, and the Synchro-Tilt Mechanism couples the Seat and Backrest for recline. A pair of 4D Armrest units and an optional Headrest complete the supported contact points.

How it works

Load travels from the occupant through the seat pan into the Synchro-Tilt Mechanism, a cast-steel housing that bolts to the top of the Pneumatic Gas Lift. The gas lift is a sealed nitrogen cylinder: pulling the height lever opens its valve, and the occupant's weight or the unloaded spring force raises or lowers the seat before the valve relocks the column at the chosen height. The cylinder seats into the tapered socket of the Base Assembly, a die-cast aluminium spider whose five arms each carry a swivel caster.

Recline is governed by the synchro-tilt mechanism. As the sitter leans back, the backrest reclines roughly twice as far as the seat tips, keeping the thighs supported and the eyes level with the screen. A coil tension spring inside the housing resists this motion, and a geared tension knob preloads the spring to match the sitter's weight; a lock lever fixes recline at several stops. The Backrest frame tensions an elastomeric mesh panel that flexes to the spine, while an adjustable lumbar pad presses into the mesh at the lower back. Each 4D Armrest adjusts in four axes so the forearms stay supported regardless of seat height or recline angle.

Ergonomic Office Chair parts and their functions

8 top-level parts · 48 parts in total · full bill of materials below
Ergonomic Office Chair parts diagram: 1 base assembly, 2 pneumatic gas lift, 3 synchro-tilt mechanism, 4 seat, 5 backrest, 6 4D armrest, 7 headrest, 8 fastener set. 48 parts in 8 top-level items.
Ergonomic Office Chair parts diagram. Numbers match the table below; each box is one top-level part or assembly with what it contains.
#PartQtyWhat it does
1 Base Assembly 2 parts 1× 5-star aluminium base with casters
2 Pneumatic Gas Lift 4 parts 1× Pneumatic height cylinder
3 Synchro-Tilt Mechanism 6 parts 1× Synchro-tilt seat mechanism
4 Seat 4 parts 1× Seat pan + cushion
5 Backrest 6 parts 1× Mesh back with lumbar
6 4D Armrest 4 parts 2× Left + right 4D armrests
7 Headrest 3 parts 1× Adjustable headrest (optional)
8 Fastener Set 1× Bolts and washers

3D model

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Build & assembly graph

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Bill of materials for Ergonomic Office Chair

8 top-level lines · 40 rows shown · 48 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Base Assembly 2 parts office-chair-base 1× 1 16 assembly
1.1 5-Star Aluminium Base office-chair-base-spider 1× 1 · part
1.2 Caster 3 parts office-chair-caster 5× 5 3 assembly
1.2.1 Caster Wheel office-chair-caster-wheel 1× 5 · part
1.2.2 Caster Stem office-chair-caster-stem 1× 5 · part
1.2.3 Ball Bearing ball-bearing 1× 5 · part
2 Pneumatic Gas Lift 4 parts office-chair-gas-lift 1× 1 4 assembly
2.1 Class-4 Gas Spring office-chair-gas-spring 1× 1 · part
2.2 Lift Cylinder office-chair-lift-cylinder 1× 1 · part
2.3 Guide Bushing office-chair-lift-bushing 1× 1 · part
2.4 Valve Actuation Pin office-chair-lift-actuator 1× 1 · part
3 Synchro-Tilt Mechanism 6 parts office-chair-mechanism 1× 1 6 assembly
3.1 Mechanism Housing office-chair-mech-housing 1× 1 · part
3.2 Coil Spring coil-spring 1× 1 · part
3.3 Tension Knob office-chair-tension-knob 1× 1 · part
3.4 Lock Lever office-chair-lock-lever 1× 1 · part
3.5 Tilt Pivot Axle office-chair-tilt-pivot 1× 1 · part
3.6 Fastener Set fastener-set 1× 1 · part
4 Seat 4 parts office-chair-seat 1× 1 4 assembly
4.1 Seat Pan office-chair-seat-pan 1× 1 · part
4.2 Foam Cushion office-chair-seat-foam 1× 1 · part
4.3 Upholstery Fabric office-chair-seat-fabric 1× 1 · part
4.4 Seat Slider office-chair-seat-slider 1× 1 · part
5 Backrest 6 parts office-chair-backrest 1× 1 6 assembly
5.1 Backrest Frame office-chair-back-frame 1× 1 · part
5.2 Mesh Panel office-chair-back-mesh 1× 1 · part
5.3 Lumbar Support office-chair-lumbar 1× 1 · part
5.4 Lumbar Adjuster office-chair-lumbar-adjuster 1× 1 · part
5.5 Back Foam Pad office-chair-back-foam 1× 1 · part
5.6 Back Upholstery office-chair-back-fabric 1× 1 · part
6 4D Armrest 4 parts office-chair-armrest 2× 2 4 assembly
6.1 Arm Post office-chair-arm-post 1× 2 · part
6.2 Height Button office-chair-arm-button 1× 2 · part
6.3 Arm Pad office-chair-arm-pad 1× 2 · part
6.4 Arm Slide Mechanism office-chair-arm-slide 1× 2 · part
7 Headrest 3 parts office-chair-headrest 1× 1 3 assembly
7.1 Headrest Frame office-chair-headrest-frame 1× 1 · part
7.2 Headrest Pad office-chair-headrest-pad 1× 1 · part
7.3 Headrest Adjuster office-chair-headrest-adjuster 1× 1 · part
8 Fastener Set fastener-set 1× 1 · part

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Sourcing: possible vendors

Browse the supplier directory → Prices, MOQ, and lead times are algorithmic estimates, not quotes, and not claims about these companies. Company mappings are curated by keyword; est. price band $50–$3k. How estimates work
VendorHQSpecialtyMOQLead time
🇺🇸Steelcase
steelcase.com ↗
Grand Rapids, US Office furniture 200 units 6–12 wks
🇺🇸MillerKnoll
millerknoll.com ↗
Zeeland, US Furniture (Herman Miller) 200 units 6–12 wks
🇺🇸Haworth
haworth.com ↗
Holland, US Office furniture 200 units 6–12 wks
🇺🇸HNI
hnicorp.com ↗
Muscatine, US Furniture & hearth 200 units 6–12 wks
ikea.com ↗ Älmhult, SE Furniture manufacturing 200 units 6–12 wks

341-word article