Patent Application
20110304185
The present invention generally relates to a locking adjustment system for chairs. More particularly, it relates to a spiral jaw locking mechanism for an adjustment system in chairs.
Several types of chairs are provided with reclining mechanisms. Certain reclining mechanisms in chairs include a base structure that allows the seat to slide forwards and backwards and cause inclination of the back part of the seat. Current locking mechanisms that are used to stop movement of the base structure and keep the seat base from sliding typically include nut and bolt type interfaces. However, this type of interface does not provide adequate locking capability for positioning of the seat. Bolt systems are typically not very performant and sometimes are subjected to problems after long periods of use.
Several different prior art mechanisms using spiral jaws as part of an adjustment mechanism in chairs, or other apparatuses, are known to the Applicant.
U.S. Pat. No. 6,135,524 (Faller et al.) discloses a frame structure (unrelated to a chair mechanism) using a spiral jaw clutch type system for the translational movement of a rod against a spring in order to adjust the configuration of a mechanism inside a structure.
US 2007/0170767 (Oberlaender et al.) teaches an adjustment mechanism for a surgical armrest using a spiral jaw clutch type system for the adjustment of a mechanism of the armrest.
U.S. Pat. No. 5,029,940 (Golynsky et al.) teaches a chair tilt and chair height control apparatus where the tilt control mechanism uses a spiral jaw clutch type system to control the adjustment of the tilting of a section of the chair.
Other mechanisms known to the Applicant include U.S. Pat. No. 3,936,091 (Rabinowitz); U.S. Pat. No. 4,540,148 (Jann); U.S. Pat. No. 4,728,072 (Mitchell); U.S. Pat. No. 6,719,372 (Glaspie et al.); and U.S. Pat. No. 7,611,201 (Moriyama et al.).
However, none of the prior art documents cited above discloses a spiral jaw clutch mechanism for locking and unlocking an adjustment system sliding along a slotted element and associated with the positioning of a chair seat.
Consequently, there is presently a need for a chair adjustment mechanism that uses a spiral jaw clutch to offer improved locking performance and operate reliably over a longer period of time.
An object of the present invention is to provide a locking chair adjustment mechanism that addresses at least one of the above-mentioned needs.
According to the present invention, there is provided a locking chair adjustment mechanism for adjusting a position of a chair component, the mechanism comprising:
The use of the spiral jaw clutch and spring mechanism provides a low cost solution offering improved locking capabilities than traditional braking mechanism for certain applications, while operating reliably over a period of time.
These and other objects and advantages of the invention will become apparent upon reading the detailed description and upon referring to the drawings in which:
In the following description, the same numerical references refer to similar elements. The embodiments shown in the figures are preferred.
Moreover, although the present invention was primarily designed for use with adjustment of a seat bottom of a chair, it may be used with other types of chair components, as apparent to a person skilled in the art. For this reason, expressions such as “chair” or “seat” used herein should not be taken as to limit the scope of the present invention and include all other kinds of chair assemblies or items with which the present invention could be used and may be useful.
Moreover, in the context of the present invention, expressions such as “structure” and any other equivalent expressions and/or compound words thereof known in the art will be used interchangeably.
In addition, although the preferred embodiments of the present invention are illustrated in the accompanying drawings and although the preferred embodiments of the adjustment mechanism as shown consist of certain geometrical configurations as explained and illustrated herein, not all these components and geometries are essential to the invention and thus should not be taken in their restrictive sense, i.e. should not be taken as to limit the scope of the present invention. It is to be understood, as also apparent to a person skilled in the art, that other suitable components and cooperations thereinbetween, as well as other suitable geometrical configurations may be used for the adjustment mechanism and corresponding parts according to the present invention, as briefly explained and inferred herein, without departing from the scope of the invention.
Referring to any one of
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Preferably, the chair component is a chair seat bottom whose displacement is reflected in the inclination of the back part of the seat. However, the adjustment mechanism according to the present invention may be used for adjustment of other chair components.
Although preferred embodiments of the present invention have been described in detail herein and illustrated in the accompanying drawings, it is to be understood that the invention is not limited to these precise embodiments and that various changes and modifications may be effected therein without departing from the scope or spirit of the present invention.
