WO1998002064A1 - Collapsible chair - Google Patents

Abstract

A collapsible chair (10) has a seat material (12) and a plurality of pairs of cross braces (20, 22, 24, 26, 28, 30, 32, 34) pivotally joined at midpoints of each member thereof. The members have flattened ends. The pairs of cross braces being pivotally joined by a plurality of like connectors (36) in an end-to-end manner forming an endless lattice structure. The seat material (12) engages the like connectors (36) along an upper edge of the lattice structure. The collapsible chair is movable between a collapsed condition wherein the ends of the members are urged together compressing the cross braces and seat material and an open, or deployed, condition wherein the seat material (12) restrains the ends from moving apart and presents a seating surface. Each of the connectors (36) has a slot for receiving an end of the members and a rivet is used to couple the connector within the slot. The members (20, 22) have an offset flattened mid-section whereby the ends thereof move in substantially the same plane of pivotal rotation when the chair is moved between the collapsed and deployed conditions.

Description

Collapsible Chair Reference to Related Application

This application claims the benefit of U S Provisional Application No 60/021656, filed July 12, 1996 Background of the Invention

FIELD OF THE INVENTION

This invention relates generally to collapsible chairs, and more particularly, to an improved structure for an accordion type collapsible chair

DESCRIPTION OF THE RELATED ART Accordion style collapsible chairs generally employ metal tubing and a woven mesh construction Pairs of metal tubes are pivotally joined together and are pivotally attached to molded plastic foot pad connectors Usually metal rivets attach the metal tubes to the foot pads

Fig 5, illustrates a prior art foot pad connector 100 The foot pad connector has a central cylinder 1 14 having orthogonal tabs 1 16 and 1 18 that extend radially outward from a central axis of the cylinder The metal tubing (not shown in this figure) must be pivotally coupled to one side or the other of a tab. In order for the collapsible chair to be symmetrical, one of the pair of tubes must be connected on the inside, while the other of the pair connects on the outside For the foot connectors, the arrangement provided adequate strength However, when such an arrangement was used for the upper forward connectors joining the mesh seat to the cross braces, the torque forces caused by a person sitting on the seat created severe twisting forces that were transmitted through the coupling rivets The twisting forces cause shearing of the rivets, and consequently, premature failure whereby the chair becomes unusable

Further, different designs of connectors were used for different locations on the chair This requires additional molds and also a greater number of parts to be maintained as inventory for the manufacture and assembly of the chair

Summary of the Invention

The disadvantages of the prior art are overcome by the present invention that provides a collapsible chair having improved connections capable of resisting twisting conditions imposed by a person sitting on the chair It is desirable to provide a collapsible chair having a seat material and a plurality of pairs of cross members pivotally joined at midpoints thereof The pairs of cross members have flattened ends and are pivotally joined by a plurality of like connectors to form an endless lattice structure. The seat material engages the like connectors along one side of the lattice structure The collapsible chair has a collapsed condition wherein the ends of the members of the pairs of cross braces are urged together, compressing the cross members and the seat material. There is additionally an open condition for the chair wherein the seat material restrains the ends from moving apart. Each of the connectors has a slot for receiving an end of the pairs of cross members and a hole thereacross for accommodating a rivet that pivotally connects the connector to the slot. Each of the cross members has an offset flattened section for pivotally joining the members of the pair of cross braces together, whereby the ends thereof travel in substantially the same plane.

In accordance with a first aspect of the invention, there is provided a chair structure having collapsed and deployed conditions. The chair structure is provided with a seating web formed of a flexible material. A plurality of cross braces are provided, each formed of a pair of support members having flattened ends and offset flattened mid-sections The support members are pivotally coupled to one another at their respective flattened mid-sections whereby the coupled support members are pivotable with respect to one another substantially in the same plane of pivotal rotation. A plurality of connectors join the plurality of cross braces in an end-to-end manner to form an endless lattice structure having an upper portion for forming a seating region, and a lower portion. Each connector has a slot for receiving an associated flattened end of a support member. In addition, there is provided a plurality of pivot coupling members, each for engaging pivotally the slot of a respective one of the plurality of connectors and the flattened end of its respectively associated support member. A web coupler for couples the seating web to predetermined ones of the plurality of connectors in the upper portion of the lattice structure.

In this manner, when the chair structure is in the collapsed condition, the flattened ends of the support members are urged together compressing the cross braces and the seating web, and when the chair structure is in the deployed condition, a tensile force is applied to the seating web via the web coupling means, whereby a seating surface is presented and the flattened ends of the cross braces are restrained from pivoting further apart. In one embodiment of this aspect of the invention, the plurality of pivot coupling members are in the form of a plurality of rivets The slot of each connector is formed of a pair of substantially parallel tabs integrally formed with the connector, and the associated rivet is arranged to engage across the parallel tabs with the flattened end interposed therebetween so as to be pivotable about the rivet Each of the connectors is further provided with a base portion and a central collar portion that is integrally formed with the base portion The central collar portion is adapted to engage respective ones of the web coupling means, whereby the pair of substantially parallel tabs is integrally formed with the base portion and the central collar portion highly advantageous specific illustrative embodiment of the invention, the central collar portion has an aperture arranged axially therethrough for engaging the respective one of the web coupling means

In accordance with a further aspect of the invention, there is provided an arrangement for coupling support member to one another The arrangement is provided with a base portion having a first and second surfaces, and a central collar portion integrally formed with the base portion The central collar portion is arranged on the first surface of the base portion and is integrally formed therewith Additionally, there is provided a first pair of substantially parallel tabs integrally formed with the base portion and the central collar portion for forming a first slot The through holes in the parallel tabs are arranged axially in registration with one another, for accommodating therethrough a pivot axle

In accordance with a specific illustrative embodiment of the invention of this further aspect of the invention, there is provided a second pair of substantially parallel tabs integrally formed with the base portion and the central collar portion for foi ing a second slot, there being further provided a through hole in each of the second pair of parallel tab The through holes are axially in registration with one another, for accommodating therethrough a second pivot axle The first and second slots are arranged orthogonal to one another, and there is further provided an arrangement in the central collar portion for engaging a web coupler In a practicable embodiment, the arrangement in the central collar portion for engaging a web coupler is in the form of a substantially annular surface of an apertui e arranged in the central collar portion The aperture in the central collar portion has an axis that is coincident with an imaginary line of intersection of the first and second slots Brief Description of the Drawing

Comprehension of the invention is facilitated by reading the following detailed description, in conjunction with the annexed drawing, in which

Fig 1 is an isometric representation of a specific illustrative embodiment of the invention of the collapsible chair of the present invention,

Fig. 2 is an isometric representation of a connector for use in the collapsible chair of Fig. 1;

Fig 3 is a side elevational view of a pair of tubular cross members of the collapsible chair of Fig. 1 , Fig 4 is a front elevational view of a pair of tubular cross members of Fig 3; and

Fig 5 is an isometric representation of a connector of the prior art

Detailed Description

Fig 1 shows a specific illustrative embodiment of the invention of a collapsible chair 10 constructed in accordance with the present invention Chair 10, in general terms, has a seat 12, a back 14, rear legs 16 and 18, pairs of cross members or braces 20 and 22, 24 and 26, 28 and 30 and 32 and 34 The pair of cross braces 20 and 22, 24 and 26, 28 and 30 and 32 and 34 are pivotally connected together at connectors 36 in end-to-end fashion so as to form an endless lattice structure (not specifically designated)

Back 14 is preferably made of a woven NYLON mesh material The back is sewn to produce a sleeve 38 at each end for slidably receiving an upper end of rear legs 16 and 18

Optionally, back 14 is provided with a padding (not shown) for improving comfort Seat 12 is preferably also made of a woven NYLON material

Seat 12 has a generally square shape having a reinforcing corner layer 40, preferably a leather or artificial leather material, sewn to each corner Centered in the corner layer 40 is a grommet 42 Grommets 42 are sized to allow sliding movement along rear legs 16 and 18 A sized plug 44 extends through grommets 42 at the front corners of seat 12 through a bore 46 of connector 36 to secure the front portion of seat 12 to the connectors 36 Preferably, plug 44 engages connector 36 in a snap fit or a friction fit to retain securely the seat 12 to the connectors 36 along an upper edge of the lattice structure Referring to Fig 5, the prior art connector 100 is illustrated The connector 100, as previously discussed, generally has a disc-shaped base 1 12, an upstanding offset cylinder 1 14 and mounting tabs 116 and 1 18 extending orthogonally with respect to each other, the base 1 12, and to cylinder 1 14 The cross braces of the prior art are tubular In order for the chair to collapse, one of the pairs of cross braces must be pivotally connected to an outside of one of the tabs 1 16 or 1 18 while the other of the cross braces must be connected to the inside

For the connectors that function as the feet of the chair, the known arrangement provided adequate strength However when such an arrangement was used for the upper forward connectors joining the seat to the cross braces, the added torque created by a person sitting on the seat created severe twisting forces being transmitted through the rivet The twisting forces sheared the rivets used to joined the connectors to the cross braces

Fig 2 is an isometric representation of a connector for use in the collapsible chair of Fig 1 In this figure, connector 36 is illustrated Connector 36 has a base 48 having a generally triangular outline One of the corners or base 48 has a collar 50 with through-bore 46 Extending orthogonally from collar 50 and base 48 are pairs of tabs 52 and 54 and 56 and 58 Tabs 52 and

54, and 56 and 58 extend parallel to each other and and in spaced relation to define a slot for receiving an end of cross braces 20 and 22, 24 and 26, 28 and 30 and 32 and 34 Through-bore 46 has an axis (not shown) that extends transverse to base 48 The slots define imaginary planes (not shown) that, in this specific illustrative embodiment of the invention, intersect at the axis of the through-bore Each of tabs 52, 54, 56 and 58 has a bore 60 for receiving a rivet or other suitable fastener that pivotally joins the ends of the cross braces to the connector 36

Figs 3 and 4, are front and side representations of the members of the cross braces of the present invention Each of members 20 and 22, 24 and 26, 28 and 30 and 32 and 34 are identical and symmetrical Accordingly, only one pair of members 20 and 22 is needed to be illustrated to be fully understood

Each member 20 and 22 or the cross braces are preferably made of a tubular steel Each of the ends of the members are pressed or stamped until opposite sides are together forming ends 62 and 64 Holes 66 and 68 are drilled or stamped in respective ends 62 and 64 The middle portion of the members is pressed to present opposite flat sui faces 72 and 74 and 76 and 78 At the center of each member is a drilled or stamped hole for receiving a rivet 80 or other suitable fastener to pivotally join members 20 and 22 together.

The opposite flat surfaces 74 and 76 are offset from a central longitudinal axis of the members 20 or 22. When the members 20 and 22 of the cross braces pivot in a scissor-like motion, the opposite ends 62 and 64 will be in the same plane.

In use, the ends of the pairs of cross braces are urged together pivoting about rivet 80 in a scissor-like fashion until the individual brace extends in substantially the same direction. The rearward connectors 36 will slide upwardly along the rear legs 16 and 18. The seat 12 and seat back 14 can be folded. In the collapsed condition, the chair 10 occupies substantially less volume and can easily be stored in an elongated sack for carrying or storage.

To open, the chair 10 is removed from its storage sack and the ends of the cross braces are urged outwardly until the seat 12 becomes taut restraining further outward movement of the cross braces, presenting a seat surface.

In tests conducted on the chair of the present invention, the chair has been found to have improved strength. In particular, the connector 36 is able to withstand the added torque applied the weight of person (not shown) sitting on the chair 10. The tabs 52, 54, 56 and 58 retain the end of the cross braces to prevent an angled torque from being applied to the connecting rivet.

It is apparent that the chair of the present invention could easily be modified to remove the seat back and add a plurality of like lattice structures and a common seat material to form a cot.

Although the invention has been described in terms of specific embodiments and applications, persons skilled in the art can, in light of this teaching, generate additional embodiments without exceeding the scope or departing from the spirit of the claimed invention. Accordingly, it is to be understood that the drawing and description in this disclosure are profFered to facilitate comprehension of the invention, and should not be construed to limit the scope thereof.

Claims

What is claimed is:

1. A chair structure having collapsed and deployed conditions, the chair structure comprising: a seating web formed of a flexible material; a plurality of cross braces, each formed of a pair of support members having flattened ends and offset flattened mid-sections, the support members being pivotally coupled to one another at their respective flattened mid-sections whereby the coupled support members are pivotable with respect to one another substantially coplanarly, a plurality of connectors for joining said plurality of cross braces in an end-to-end manner to form an endless lattice structure having an upper portion for forming a seating region, and a lower portion, each connector having a slot for receiving an associated flattened end of a support member; a plurality of pivot coupling members each for engaging pivotally the slot of a respective one of said plurality of connectors and the flattened end of its respectively associated support member; web coupling means for coupling the seating web to predetermined ones of said plurality of connectors in the upper portion of the lattice structure, whereby, when the chair structure is in the collapsed condition, the flattened ends of the support members are urged together compressing the cross braces and said seating web, and when the chair structure is in the deployed condition, a tensile force is applied to said seating web via said web coupling means, whereby a seating surface is presented and the flattened ends of said cross braces are restrained from pivoting further apart

2. The chair structure of claim 1 , wherein said plurality of pivot coupling members comprises a plurality of rivets. 3. The chair structure of claim 2, wherein the slot of each connector is formed of a pair of substantially parallel tabs integrally formed with said connector, and said rivet is arranged to engage across the parallel tabs with said flattened end interposed therebetween so as to be pivotable about said rivet. 4 The chair structure of claim 3, wherein said connectors are each further provided with a base portion, and a central collar portion integrally formed with said base portion, said central collar portion being adapted to engage respective ones of said web coupling means, whereby said pair of substantially parallel tabs is integrally formed with said base portion and said central collar portion

5 The chair structure of claim 4, wherein said central collar portion has an aperture arranged axially therethrough for engaging the respective one of said web coupling means 6 An arrangement for coupling support member to one another, the arrangement comprising a base portion having a first and second surfaces, a central collar portion integrally formed with said base portion, said central collar portion being arranged on the first surface of said base portion and being integrally formed therewith, and a first pair of substantially parallel tabs integrally formed with said base portion and said central collar portion for forming a first slot, there being further provided a through hole in each of the parallel tabs, the through holes being axially in registration with one another, for accommodating therethrough a pivot axle

7 The arrangement of claim 6, wherein there is further provided a second pair of substantially parallel tabs integrally formed with said base portion and said central collar portion for forming a second slot, there being further provided a through hole in each of the second pair of parallel tabs, the through holes being axially in registration with one another, for accommodating therethrough a second pivot axle

8 The arrangement of claim 7, wherein said first and second slots are arranged orthogonal to one another

9 The arrangement of claim 6, wherein there is further provided means in said central collar portion for engaging a web coupler

10 The arrangement of claim 9, wherein said means in said central collar portion for engaging a web coupler comprises a substantially annular surface of an aperture arranged in said central collar portion

11. The arrangement of claim 10, wherein the aperture arranged in said central collar portion has an axis coincident with an imaginary line of intersection of said first and second slots.