Apparatus and methods for the understructure of a chair base
AssigneeMedway Plastics Corporation
InventorsThomas A. Hutchinson, Jr., Gerald A. Hutchinson, Richard E. Hutchinson
Life of this patent
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Abstract
The embodiments relate to a geometric under structure, central and outer hub for a GFN plastic chair base. The geometric shape and dimensions are critical components to the overall strength of the chair base hub and arms when either vertical or rotational forces are applied at the central hub. The central hub is of sufficient thickness to maintain dimensional stability when the forces are applied. The overall geometry and material composition enable the hub area to be constructed with minimal plastic wall thickness while optimizing the physical strength of the article and facilitating high production rate.
Claims20
A chair base comprising an understructure and a top, the chair base further comprising:
- a central opening configured to receive a shaft of a swivel chair;
- a plurality of arms each configured to accept a caster stem;
- a hub surrounding the central opening and connected to the plurality of arms, the arms generally extending radially therefrom in an evenly spaced manner;
- a hoop structure encircling the hub and comprising:
- a plurality of hoop ribs spaced evenly around a circumference of the hub and supporting an outer wall thereof, each hoop rib extending along a radius aligned with a gap between two adjacent arms;
- a hoop wall to which the hoop ribs connect and from which the plurality of arms extends;
- and
- a plurality of hoop cores comprising voids surrounded by adjacent hoop ribs, a portion of the hoop wall, and a portion of an outer wall of the hub, each hoop core centered with one of the plurality of arms, wherein the chair base consists of a number of hoop cores that is the same as a number of the plurality of arms.
A chair base comprising:
- a plurality of arms each configured to accept a caster stem;
- a hub surrounding a central opening and connected to the plurality of arms, the arms generally extending radially therefrom in an evenly spaced manner;
- a hoop structure encircling the hub and comprising:
- a plurality of hoop ribs spaced evenly around the circumference of the hub and supporting an outer wall thereof, each hoop rib extending along a radius aligned with a gap between two adjacent arms;
- and
- a plurality of hoop cores comprising voids surrounded by adjacent hoop ribs and a portion of an outer wall of the hub, each hoop core centered to align radially with one of the plurality of arms such that the chair base has the same number of hoop cores as a number of the plurality of arms.
Dependencies are inferred from the claim text.