Chair Base Assembly

Abstract

A chair base assembly including a leg assembly, a seat support and a support column coupling the leg assembly to the seat support. Either one or both of the seat support and the leg assembly including an insert member that extends about a bore defined within each, configured to accept the support column. Such an insert member includes a winding that is outwardly deformable so as to be outwardly deformable. The insert member may include a winding of a substantially uniform wire-like member having a substantially uniform cross-sectional configuration so as to define a circular cross-section.

Description

CROSS-REFERENCE TO RELATED APPLICATION

N/A

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The invention relates in general to chairs, such as office chairs and the like, and more particularly, to a chair base assembly having a configuration which provides enhanced assembly and enhanced durability to the overall construction. The disclosure is not limited to use in association with office chairs and the like.

2. Background Art

The use of chairs, such as office chairs is known in the art. Office chairs, and the like, generally include a seating component and a support component. The seating component generally includes a typically horizontal seating surface, a substantially vertical backrest and opposing armrests. Each of these elements may be independently or dependently adjustable so as to provide a custom fit to the user. These components are each directly or indirectly coupled to a chair base assembly and more particularly to a seat support member. The seat support member is generally a robust member which provides the interface with the remainder of the chair base assembly.

The chair base assembly includes the seat support member and a leg assembly, with a support column coupling the two together. Each of the seat support member and the leg assembly include a bore that is configured to receive the opposing ends of the seat support member. As the structures tend to lighter and better performance materials, such as polymers, certain problems have been identified.

Among other problems, the bore configured to receive the support column in each of the leg assembly and the seat support tends to wear over time. Once worn sufficiently, the bore may contribute to a dramatic failure wherein the support column extends straight through the bore, collapsing the structure. Additionally, creep over time and deflection under high load can cause the support column to slip through the base support or the seat support.

A number of solutions have been provided including those disclosed in U.S. Pat. No. 5,692,715 issued to Hertel, U.S. Pat. No. 6,116,555 issued to Claus et al, U.S. Pat. No. 5,149,035 issued to Bonnema et al and U.S. Pat. No. 5,377,943 issued to Perl. These solutions have provided some improvement and resistance to failure.

Certain of the solutions include a molded and integrally formed insert member which is generally of a material harder than the remainder of either the seat support or the leg assembly, such as, for example, a metal or alloy thereof. While such a solution has been helpful, there are drawbacks. First, the metal member must be correctly sized within certain tolerances. Second, it is often difficult to properly locate the member. Finally, the member is not flexible so as to be usable with differently sized support columns or differently configured leg assemblies. There are other deficiencies with such configurations.

SUMMARY OF THE DISCLOSURE

The disclosure is directed to a chair base assembly. The chair base assembly includes a leg assembly, a seat support and a support column. The leg assembly includes a central hub with a plurality of legs extending axially outwardly therefrom. The legs have a proximal end coupled to the central hub and a distal end spaced axially outwardly therefrom.

The central hub defines a cylindrical wall having an upper end and a lower end. The cylindrical wall is inwardly tapered between the upper end and the lower end such that a cross-sectional configuration at the upper end is larger than a cross-sectional configuration of a portion of the cylindrical wall between the upper end and the lower end. The cylindrical wall has an inner surface with a channel positioned between the upper end and the lower end, with an insert member positioned within the channel. The insert member comprises a wound member configured to extend about the inner surface of the cylindrical wall at least a radial distance that is greater than half of the circumference of the inner wall. The insert member is outwardly deformable.

The seat support is configured to receive at least one of a seating surface and a back rest. The support column has an upper end coupled to the seat support and a lower end coupled to the leg assembly.

In a preferred embodiment, the insert member defines a generally cylindrical winding having a first end and a second end. The cylindrical winding extends at least about the circumference of the inner surface of the cylindrical wall with the first end and the second end being offset from each other and overlapping.

In another preferred embodiment, the insert member defines a cylindrical winding having at least two full windings.

Preferably, the insert member is outwardly elastically deformed, and wherein the configuration is maintained by the coupling of the insert member within the cylindrical wall of the central hub.

In another preferred embodiment, the insert member is positioned at the upper end of the cylindrical wall.

Preferably, the insert member comprises a winding formed from a substantially uniformly configured metal member having a substantially uniform cross-sectional configuration.

In another preferred embodiment, the leg assembly further includes a caster positioned at the distal end of each of the legs of the leg assembly.

In a preferred embodiment, the seat support further comprises a body and a seat support insert member. The body has a central bore defining an inner wall with a proximate end and a distal end. The channel is positioned within the inner wall between the proximal and distal end. The seat support insert member comprising a wound member configured to extend about the inner surface of the central bore at least a radial distance that is greater than half of the circumference of the inner surface. The seat support insert member is outwardly deformable.

In a preferred embodiment, the seat support insert member defines a generally cylindrical winding having a first end and a second end. The cylindrical winding extends at least about the circumference of the inner surface of the inner wall of the central bore with the first end and the second end being offset from each other so that they are overlapping each other.

In another preferred embodiment, the seat support insert member defines a cylindrical winding having at least two full windings.

In yet another preferred embodiment, the seat support insert member is outwardly elastically deformed. The configuration is maintained by the coupling of the seat support insert member with the inner wall of the central bore.

In yet another preferred embodiment, the seat support insert member comprises a winding formed from a substantially uniformly configured metal member having a substantially uniform cross-sectional configuration.

In another aspect of the disclosure, the disclosure is directed to a leg assembly for use in association with a chair assembly. The leg assembly comprises a central hub with a plurality of legs extending axially outwardly therefrom. The legs each have a proximal end coupled to the central hub and a distal end spaced axially outwardly therefrom. The central hub defines a cylindrical wall having an upper end and a lower end. The cylindrical wall is inwardly tapered between the upper end and the lower end such that a cross-sectional configuration at the upper end is larger than a cross-sectional configuration of a portion of the cylindrical wall between the upper end and the lower end. The cylindrical wall has an inner surface with a channel positioned between the upper end and the lower end, with an insert member positioned within the channel. The insert member comprises a wound member configured to extend about the inner surface of the cylindrical wall at least a radial distance that is greater than half of the circumference of the inner wall. The insert member is outwardly deformable.

In a preferred embodiment, the plurality of legs are integrally formed with the central hub and comprise a polymer member. Additionally, the insert member comprises a metal member which is formed from a winding having a substantially uniform cross-sectional configuration.

In another preferred embodiment, the insert member defines a generally cylindrical winding having a first end and a second end. The cylindrical winding extends at least about the circumference of the inner surface of the cylindrical wall with the first end and the second end being offset from each other and overlapping.

In a preferred embodiment, the insert member defines a cylindrical winding having at least two full windings.

In another preferred embodiment, the insert member is outwardly elastically deformed. Such a configuration is maintained by the coupling of the insert member with the cylindrical wall of the central hub.

In another preferred embodiment, the insert member is positioned at the upper end of the cylindrical wall.

In another aspect of the disclosure, the disclosure is directed to a seat support for use in association with a chair base assembly. The seat support includes a body and a seat support insert member. The body has a central bore defining an inner wall with a proximate end and a distal end. A channel is positioned within the inner wall between the proximal and distal end. The seat support insert member comprises a wound member configured to extend about the inner surface of the central bore at least a radial distance that is greater than half of the circumference of the inner surface. The seat support insert member is outwardly deformable.

In a preferred embodiment, the seat support insert member defines a generally cylindrical winding having a first end and a second end. The cylindrical winding extends at least about the circumference of the inner surface of the inner wall of the central bore with the first end and the second end being offset from each other so that they are overlapping.

In a preferred embodiment, the seat support insert member defines a cylindrical winding having at least two full windings.

In another preferred embodiment, the seat support insert member is outwardly elastically deformed. The configuration is maintained by the coupling of the seat support insert member with the inner wall of the central bore.

In a preferred embodiment, the seat support insert member comprises a winding formed from a substantially uniformly configured metal member having a substantially uniform cross-sectional configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will now be described with reference to the drawings wherein:

FIG. 1 of the drawings is a perspective view of a chair base of the present disclosure;

FIG. 2 of the drawings is an exploded perspective view of the chair base of the present disclosure;

FIG. 3 of the drawings is a partial cross-sectional view of the leg assembly of the present disclosure, showing, in particular, the central bore thereof, taken generally about lines 3-3 of FIG. 1;

FIG. 4 of the drawings is a perspective view of the insert member of the leg assembly of the present disclosure;

FIG. 5 of the drawings is a partial cross-sectional view of the seat support of the present disclosure, showing, in particular, the central bore thereof, taken generally about lines 5-5 of FIG. 1;

FIG. 6 of the drawings is a partial cross-sectional view of the chair base of the present disclosure, taken generally about lines 3-3 of FIG. 1; and

FIG. 7 of the drawings is a perspective view of the insert member of the seat support of the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and described herein in detail a specific embodiment with the understanding that the present disclosure is to be considered as an exemplification and is not intended to be limited to the embodiment illustrated.

It will be understood that like or analogous elements and/or components, referred to herein, may be identified throughout the drawings by like reference characters. In addition, it will be understood that the drawings are merely schematic representations of the invention, and some of the components may have been distorted from actual scale for purposes of pictorial clarity.

Referring now to the drawings and in particular to FIGS. 1 and 2, the chair base assembly is shown generally at 10. The chair base assembly 10 is configured for use in association with, for example, an office chair or the like. The office chair typically includes a seating surface, a back rest and opposing armrests. The seating surface generally rests on the seat support 16 which is coupled to the support column 14 and, in turn, to the leg assembly 12. The particular configuration of the office chair is generally not limited, and a number of different configurations are contemplated.

The chair base assembly 10 includes the leg assembly 12, the support column 14 and the seat support 16. With additional reference to FIG. 3, the leg assembly includes central hub 20, legs 22, such as legs 22, and casters, such as caster 24. It is contemplated that the central hub and the legs 22 comprise an integrally molded polymer based member, although other configurations are also contemplated. The central hub 20 includes cylindrical wall 30 and insert member 32. The cylindrical wall 30 comprises an elongated configuration that includes an inner surface 38 which spans between upper end 34 and lower end 36. The inner surface 38 defines a central axis with a cross-sectional configuration along the length thereof. At the upper end 34, the cross-section includes an enlarged portion with an upwardly directed upper flange 35 that extends upwardly from the upper end 34. The inner surface 38 is generally tapered from the upper end 34 to the lower end 36. In the embodiment shown, below the upper flange 35, the inner surface is generally tapered toward the lower end 36. That is, the diameter is larger at the upper end than at the lower end. In the embodiment shown, the taper between the upper and lower ends is generally uniform and substantially continuous. In other embodiments, the taper between the upper end and the lower end may be non-uniform. In still other embodiments, the inner surface may include a step-down portion or portions so as to reduce the cross-sectional configuration in more abrupt manners.

The inner surface 38, proximate the upper end 34 thereof includes channel 39 which is disposed into the surface. Insert member 32 is positioned so as to be within the channel 39. The insert member 32, as will be explained below, is positioned within the mold during the manufacturing process of the central hub. The insert member 32 comprises a winding of material, generally a metal member, that has a winding diameter that matches the cross-sectional configuration of the inner surface. With reference to FIG. 4, the insert member 32 includes first end 27 and second end 29. In the embodiment shown, the insert member comprises a metal winding that has approximately two full windings when in an unstressed configuration. The metal winding is a steel member having a cross-sectional configuration that is that of a generally circular member with a predetermined diameter. In the embodiment shown, the diameter is approximately two inches, while a number of other diameters are likewise contemplated, and this is not to be deemed limiting but, solely exemplary.

It will be understood that the insert member may comprise a winding of material that is of a different, uniform, or non-uniform cross-sectional configuration. In addition, while two full windings are disclosed, it will be understood that the insert member may include a greater or lesser number of windings. It is contemplated that the first and second ends 27, 29 of the insert member may be spaced apart from each other or may overlap. In certain embodiments, the insert member may be as small as a bit larger than half of the circumferential configuration of the inner surface proximate the channel 39.

Referring back to FIGS. 1 through 3, the legs 22 extend axially away from the central hub in a spaced apart orientation generally equally spaced about the central hub 20. While a number of different configurations are contemplated, a total of between 4 and 6 legs is contemplated. The leg 22 will be described with the understanding that the other legs are substantially identical to the leg 22.

Leg 22 extends from proximal end 40 at the central hub 20 to distal end 42 spaced apart therefrom. The leg 22 extends in a generally downward direction from the proximal end to the distal end. The leg 22 generally comprises a substantially inverted u-shaped configuration with leg upper beam 44, first side wall 46 and second sidewall 48. Within the cavity defined by the u-shaped configuration, a plurality of cross-supports 50 are positioned thereacross in a spaced apart configuration. The cross-supports 50 provide additional rigidity to the u-shaped configuration. The cross-supports may have a plurality of different configurations. For example, they may extend in an intersecting criss-cross configuration, or may extend generally parallel to each other. A number of different configurations are contemplated.

As is shown in FIG. 3, a caster bore 52 is positioned at the distal end 42 of the leg 22. The caster bore 52 is generally positioned so as to be substantially parallel to the central hub 20 in a spaced apart configuration. Caster 24 includes caster axis 56 and caster wheel assembly 58. The caster axis 56 is offset relative to the axis rotation of the caster wheel assembly and perpendicular thereto. The caster axis 56 is dimensioned so as to extend into the caster bore 52 of the distal end of the leg 22. Generally, an assembly is positioned on each of the caster axis 56 and the caster bore 52 so as to capture and releasably lock the two structures together and to each other. In certain embodiments, the caster 24 may be replaced with a leg member that provides for a generally fixed configuration on the ground.

With reference to FIGS. 1, 2 and 7, the support column 14 comprises a cylinder member that includes upper end 60 and lower end 64. The cylinder member generally includes an outer wall configuration which may define several different cross-sectional configurations. The support column is configured to couple the seat support 16 to the leg assembly 12. In certain configurations, the support column 14 comprises an adjustable member comprising multiple nesting cylinders. The different cylindrical members can be adjusted pneumatically, hydraulically, mechanically, among other configurations. As will be explained below, the upper end 60 interfaces with the seat support 16 and the lower end 64 interfaces with the central hub 20 of the leg assembly 12.

Seat support 16 is shown in FIGS. 1 and 5 as comprising body 70, central bore 72 and insert member 74. The body 70 provides the support for the seating surface and the backrest, typically. Generally, the seat support provides the basis upon which the upper portion of the seat is coupled and configured. The body may comprise a molded polymer member, a metal member, or a combination of members.

The central bore 72 extends into the body 70 and includes inner wall 77, proximal end 78, distal end 79 and channel 80. The inner wall includes a generally conical configuration which tapers inwardly from the proximal end 78 to the distal end 79. The channel is generally molded into the inner wall so as to provide a receptacle for the insert member 74.

With reference to FIG. 6, the insert member 74 is much like the insert member 32 of the leg assembly 12. The insert member is also positioned within the mold during the manufacturing process of the body 70. The insert member 74 comprises a winding of material, generally a metal member, that has a winding diameter that matches the cross-sectional configuration of the inner surface. The insert member 74 includes first end 82 and second end 84. In the embodiment shown, the insert member comprises a metal winding that has approximately two full windings when in an unstressed configuration. The metal winding is a steel member having a cross-sectional configuration that is that of a generally circular member with a predetermined diameter. In the embodiment shown, the diameter is approximately one inch, while a number of other diameters are likewise contemplated, and this is not to be deemed limiting but, solely exemplary.

It will be understood that the insert member may comprise a winding of material that is of a different, uniform, or non-uniform cross-sectional configuration. In addition, while two full windings are disclosed, it will be understood that the insert member may include a greater or lesser number of windings. It is contemplated that the first and second ends 82, 84 of the insert member may be spaced apart from each other or may overlap. In certain embodiments, the insert member may be as small as a bit larger than half of the circumferential configuration of the inner surface proximate the channel 80.

To manufacture the chair base assembly, the leg assembly is molded in an injection molding press. Generally, the insert member 32 is positioned within the mold, around the portion that forms the cylindrical wall 30. When the polymer material is injected into the mold, the insert member 32 is driven by the force toward the bottom of the mold, which is the location of formation of the upper end 34 of the cylindrical wall 30. The force of the molten material within the mold directs the insert member to the desired location at the upper end 34. The insert member 32 can elastically deform outwardly in the event that the cross-sectional configuration of the insert member 32 is not within the desired tolerance, so that it is pushed into the desired orientation. That is, advantageously, it is not necessary to size the insert member to the tolerances required for a ring member, as the insert member can be deformed into the proper diameter during the molding process through the injection of the material itself, or through the insertion process by a user.

Once molded, the insert member 32 will form the channel 39 and remain within the channel 39. In each instance, the insert member 32 has the proper and desired cross-sectional configuration and opening dimension, as well as the proper position within the molded member. Once fully formed, the casters 24 can be assembled onto the respective one of the legs, such as leg 22. In particular, the caster axis 56 of each caster is inserted into the corresponding caster bore 52 until each desired caser bore 52 includes a caster coupled thereto.

Similarly, the seat support is formed through an injection molding press, in a preferred embodiment. In such a configuration, the insert member 74 is positioned within the mold. The injection of polymer material into the mold forces the insert member 74 toward the desired orientation within the mold. If required, the insert member 74 is expanded by the mold and through the force of the injected material. Once formed, the insert member 74 defines channel 80 and is integrated with the seat support at the desired orientation.

In either instance, the insert member 32 and the insert member 74 provide additional support to receive and capture the respective end of the support column 14 so as to engage the same at the desired location. In addition, the member is generally more resistant to wear than the surrounding material, thereby providing additional durability to the connection between the support column and the seat support and the leg assembly and the seat support. In addition, through the configuration and elastic deformability of the insert member, the insert member can be configured to adapt (and during molding of the respective leg assembly and seat support) to the precise desired configuration. Even when deformed, the insert member has cross-sectional configuration that provides the necessary support within the cylindrical wall of the central hub, and also within the central bore of the seat support.

The foregoing description merely explains and illustrates the invention and the invention is not limited thereto except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modifications without departing from the scope of the invention.

Claims

1. A chair base assembly comprising:

a leg assembly having a central hub with a plurality of legs extending axially outwardly therefrom, the legs having a proximal end coupled to the central hub and a distal end spaced axially outwardly therefrom, the central hub defining a cylindrical wall having an upper end and a lower end, being inwardly tapered between the upper end and the lower end such that a cross-sectional configuration at the upper end is larger than a cross-sectional configuration of a portion of the cylindrical wall between the upper end and the lower end, the cylindrical wall having an inner surface with a channel positioned between the upper end and the lower end, with an insert member positioned within the channel, the insert member comprising a wound member configured to extend about the inner surface of the cylindrical wall at least a radial distance that is greater than half of the circumference of the inner wall, the insert member being outwardly deformable;

a seat support configured to receive at least one of a seating surface and a back rest; and

a support column having an upper end coupled to the seat support and a lower end coupled to the leg assembly.

2. The chair base assembly of claim 1 wherein the insert member defines a generally cylindrical winding having a first end and a second end, the cylindrical winding extending at least about the circumference of the inner surface of the cylindrical wall with the first end and the second end being offset from each other and overlapping.

3. The chair base assembly of claim 2 wherein the insert member defines a cylindrical winding having at least two full windings.

4. The chair base assembly of claim 3 where the insert member is outwardly elastically deformed, and wherein the configuration is maintained by the coupling of the insert member with the cylindrical wall of the central hub.

5. The chair base assembly of claim 4 wherein the insert member is positioned at the upper end of the cylindrical wall.

6. The chair base assembly of claim 2 wherein the insert member comprises a winding formed from a substantially uniformly configured metal member having a substantially uniform cross-sectional configuration.

7. The chair base assembly of claim 2 wherein the leg assembly further includes a caster positioned at the distal end of each of the legs of the leg assembly.

8. The chair base assembly of claim 1 wherein the seat support further comprises:

a body having a central bore defining an inner wall with a proximate end and a distal end, a channel is positioned within the inner wall between the proximal and distal end; and

a seat support insert member comprising a wound member configured to extend about the inner surface of the central bore at least a radial distance that is greater than half of the circumference of the inner surface, the seat support insert member being outwardly deformable.

9. The chair base assembly of claim 8 wherein the seat support insert member defines a generally cylindrical winding having a first end and a second end, the cylindrical winding extending at least about the circumference of the inner surface of the inner wall of the central bore with the first end and the second end being offset from each other and overlapping.

10. The chair base assembly of claim 9 wherein the seat support insert member defines a cylindrical winding having at least two full windings.

11. The chair base assembly of claim 10 where the seat support insert member is outwardly elastically deformed, and wherein the configuration is maintained by the coupling of the seat support insert member with the inner wall of the central bore.

12. The chair base assembly of claim 9 wherein the seat support insert member comprises a winding formed from a substantially uniformly configured metal member having a substantially uniform cross-sectional configuration.

13. A leg assembly for use in association with a chair base assembly comprising:

a central hub with a plurality of legs extending axially outwardly therefrom, the legs having a proximal end coupled to the central hub and a distal end spaced axially outwardly therefrom, the central hub defining a cylindrical wall having an upper end and a lower end, being inwardly tapered between the upper end and the lower end such that a cross-sectional configuration at the upper end is larger than a cross-sectional configuration of a portion of the cylindrical wall between the upper end and the lower end, the cylindrical wall having an inner surface with a channel positioned between the upper end and the lower end, with an insert member positioned within the channel, the insert member comprising a wound member configured to extend about the inner surface of the cylindrical wall at least a radial distance that is greater than half of the circumference of the inner wall, the insert member being outwardly deformable.

14. The leg assembly of claim 13 wherein the plurality of legs are integrally formed with the central hub and comprise a polymer member, with the insert member comprising a metal member which is formed from a winding having a substantially uniform cross-sectional configuration.

15. The leg assembly of claim 13 wherein the insert member defines a generally cylindrical winding having a first end and a second end, the cylindrical winding extending at least about the circumference of the inner surface of the cylindrical wall with the first end and the second end being offset from each other and overlapping.

16. The leg assembly of claim 15 wherein the insert member defines a cylindrical winding having at least two full windings.

17. The leg assembly of claim 16 where the insert member is outwardly elastically deformed, and wherein the configuration is maintained by the coupling of the insert member with the cylindrical wall of the central hub.

18. The leg assembly of claim 13 wherein the insert member is positioned at the upper end of the cylindrical wall.

19. A seat support for use in association with a chair base assembly comprising:

a body having a central bore defining an inner wall with a proximate end and a distal end, a channel is positioned within the inner wall between the proximal and distal end; and

a seat support insert member comprising a wound member configured to extend about the inner surface of the central bore at least a radial distance that is greater than half of the circumference of the inner surface, the seat support insert member being outwardly deformable.

20. The seat support of claim 19 wherein the seat support insert member defines a generally cylindrical winding having a first end and a second end, the cylindrical winding extending at least about the circumference of the inner surface of the inner wall of the central bore with the first end and the second end being offset from each other and overlapping.

21. The chair base assembly of claim 20 wherein the seat support insert member defines a cylindrical winding having at least two full windings.

22. The chair base assembly of claim 21 where the seat support insert member is outwardly elastically deformed, and wherein the configuration is maintained by the coupling of the seat support insert member with the inner wall of the central bore.

23. The chair base assembly of claim 20 wherein the seat support insert member comprises a winding formed from a substantially uniformly configured metal member having a substantially uniform cross-sectional configuration.