WO2021062720A1

WO2021062720A1 - Collapsible chairs

Info

Publication number: WO2021062720A1
Application number: PCT/CN2019/109626
Authority: WO
Inventors: Hongshan SHEN; Scott Richard THOMAS; Gerardo David AYALA; Benjamin Moore; James Ghormley
Original assignee: Datafly Commerce Inc.
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2021-04-08

Abstract

A collapsible chair includes a pair of hub assemblies (110a, 110b), to which pairs of legs (103a, 104b,103b, 104a) and arms (101a, 102a, 101b, 102b) are rotatably coupled, and a crossbar (105) having end portions, to which each hub assembly (110a, 110b) is rotatably coupled. Each leg (103a, 104b, 103b, 104a) or arm (101a, 102a, 101b, 102b) has one end portion that includes a pinion gear (201a, 202a, 203a, 204a) rotatably coupled to a hub housing (210) of each hub assembly (110a, 110b). Each hub assembly (110a, 110b) includes a hollow rack member (340) having exterior teeth that engage with the pinion gears (201a, 202a, 203a, 204a) of the legs and arms (103a, 104b, 103b, 104a, 101a, 102a, 101b, 102b). Each end portion of the crossbar (105) includes helical or diagonal grooves (442) that mate with corresponding ridges (342) on the interior surface of the hollow rack member (340). As the legs and arms (103a, 104b, 103b, 104a, 101a, 102a, 101b, 102b) are moved towards a collapsed position, the pinion gears (201a, 202a, 203a, 204a) cause the rack members (340) to move outwardly from each other and the grooves (442) cause the hub assemblies (110a, 110b) to rotate in opposite directions such that the arms and legs (103a, 104b, 103b, 104a, 101a, 102a, 101b, 102b) interleave with each other.

Description

COLLAPSIBLE CHAIRS

TECHNICAL FIELD

This disclosure is generally directed to collapsible chairs. More particularly, this disclosure is directed to compact, collapsible chairs designed to reduce manufacturing costs while ensuring ease-of-use and robustness for outdoor activities.

BACKGROUND

For decades, folding or collapsible chairs have been widely used because they can be collapsed down to a size that is easy to transport and compact for storage. Because of their portability, collapsible chairs are increasingly being used during outdoor activities, where seating options are limited. As collapsible chairs are often carried considerable distances, such as during hiking or backpacking, collapsible chairs are designed to be lightweight. However, such collapsible chairs may not be robust enough to withstand numerous uses during outdoor activities and may be too large to fit in a backpack or to be carried without difficulty. Moreover, the collapsible chairs are often difficult to set up and collapse and quickly wear down after repeated set-up and collapse cycles.

SUMMARY

In another aspect, this disclosure features a collapsible chair. The collapsible chair includes a crossbar including a first end portion and a second end portion. The first and second end portions each include at least one lengthwise groove. The collapsible chair also includes a first hub and a second hub rotatably coupled to the first end portion and the second end portion, respectively. The first hub and the second hub each including a rack gear having an inner portion and an outer portion. The inner portion includes at least one ridge that mates with the least one lengthwise groove. The outer portion includes gear teeth. The collapsible chair also includes two arms and two legs rotatably coupled to each of the first hub and the second hub. The two arms and the two legs each include end portions with a pinion gear that meshes with a portion of the teeth of the rack gear. The collapsible chair also includes the first hub and the second hub rotate about the crossbar in opposite directions as the arms and legs are rotated towards the crossbar.

In aspects, implementations of this disclosure may include one or more of the following features. The at least one lengthwise groove may be a linear or nonlinear groove. The nonlinear groove may be a helical or curved groove. The collapsible chair may also include a locking housing coupled to each of the first and second end portions of the crossbar at an outer side of each of the first and second hubs, respectively. The locking housing may include tabs. The end portions of the two arms and two legs may include locking channels that mate with the tabs.

The crossbar includes a center portion and the first and second end portions of the crossbar may be first and second crossbar connectors, respectively, which may be coupled to the center portion of the crossbar. A portion of each of the first and second crossbar connectors may pass through a hollow portion of the rack gear and may be coupled to the locking housing of each of the first and second hubs. The collapsible chair may also include an elastic member coupling the first and second end portions of the crossbar to the first and second locking housings, respectively. The elastic member may be a spring or a rubber band. The spring may be a leaf spring. The two arms may be backrest arms, each of which includes a first arm and a second arm including end portions that may be rotatably coupled to each other such that the first arm and the second arm can be folded together.

The collapsible chair may also include a chair cover configured to couple to end portions of the arms. The collapsible chair may also include chair cover connectors, each chair cover connector configured to couple between an end portion of each arm and a portion of the chair cover. The end portion of each arm may be hollow and each chair cover connector may include a cap, a male member coupled to the cap and configured to mate with the end portion of each arm, a retaining member coupled to the bridge member and configured to couple to each arm, and a bridge member coupled between the cap and the retaining member, the bridge member and a portion of each arm forming an aperture configured to receive a strap coupled to the chair cover. The retaining member may be an annular member configured to fit around each arm. The male member may be configured to be interference-fitted into the end portion of each arm.

In another aspect, this disclosure features a hub assembly of a collapsible chair. The hub assembly includes a hub housing. The hub assembly also includes a hollow rack member including inner and outer surfaces. At least one ridge protrudes from the inner surface and is configured to mate with and translate along at least one groove of a center axle to cause the hub housing to rotate with respect to the center axle. The outer surface includes teeth. The hub assembly also includes pinion arms rotatably coupled to the hub housing and includes respective pinions, which mesh with different portions of the teeth of the hollow rack member. The hub assembly also includes the pinion arms, which, when rotated towards the center axle, drive the hollow rack member along a length of the center axle.

In another aspect, this disclosure features a collapsible chair. The collapsible chair includes a center axle having a first end portion and a second end portion. The first and second end portions each include at least one lengthwise groove. The collapsible chair also includes a first hub and a second hub rotatably coupled to the first end portion and the second end portion, respectively. The first hub and the second hub each include a hollow rack having an interior portion and an exterior portion. The interior portion includes at least one ridge that mates with a least one helical groove. The exterior portion includes gear teeth. The collapsible chair also includes pinion axles rotatably coupled to each of the first hub and the second hub. The pinion axles have respective end portions with a pinion gear that mates with the gear teeth. The collapsible chair also includes the first hub and the second hub rotate about the center axle in opposite directions when the pinion axles are rotated towards the center axle.

In another aspect, this disclosure features a method of manufacturing a collapsible chair. The method of manufacturing includes fixing a hollow rack member to an inner portion of a hub housing. The method of manufacturing also includes disposing pinion arms in arm channels defined by pairs of fin members, respectively, of the hub housing so that the pinions of the pinion arms mesh with gear teeth on different portions of the hollow rack member. The method of manufacturing also includes inserting axles through respective apertures of the pairs of fin members and the pinion arms. The method of manufacturing also includes passing a center axle connector through the hollow rack so that interior ridges of the hollow rack engage with exterior grooves of the center axle connector. The method of manufacturing also includes passing a bolt through the center axle connecter and a spring. The method of manufacturing also includes coupling the bolt to a locking housing. The method of manufacturing also includes coupling arms to a portion of the pinion arms. The method of manufacturing also includes coupling legs to the remaining portion of the pinion arms. The method of manufacturing also includes coupling a center axle to the center axle connector.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects and features of the disclosure are described hereinbelow with reference to the drawings, wherein:

FIG. 1A is a perspective view of a collapsible chair frame in accordance with an aspect of this disclosure;

FIG. 1B is a front view of the collapsible chair frame of FIG. 1A;

FIG. 1C is a side view of the collapsible chair frame of FIG. 1A;

FIG. 1D is a rear view of the collapsible chair frame of FIG. 1A;

FIG. 2A is a perspective view of the inner side of a hub assembly of FIG. 1A;

FIG. 2B is a side view of the outer side of the hub assembly of FIG. 2A;

FIG. 2C is a side view of the inner side of the hub assembly of FIG. 2A;

FIG. 2D is a front view of the hub assembly of FIG. 2A;

FIG. 3A is an exploded, perspective view of the inner side of the hub assembly of FIG. 2A;

FIG. 3B is an exploded, perspective view of the outer side of the hub assembly of FIG. 3A;

FIG. 4 is an exploded, perspective view of a hub assembly of FIG. 1A;

FIG. 5A is a perspective view of the inner side of a hub housing of a hub assembly of FIG. 1A;

FIG. 5B is a perspective view of the outer side of the hub housing of FIG. 5A;

FIG. 6A is a side view of the outer side of a hub assembly of FIG. 1A;

FIG. 6B is a sectional view of the hub assembly of FIG. 6A taken along the line B-B;

FIG. 6C is a perspective view of a portion of the hub assembly of FIG. 6A;

FIG. 6D is a side view of a portion of the hub assembly of FIG. 6A;

FIG. 7 is a perspective view of an example collapsible chair according to an aspect of this disclosure;

FIG. 8A is an exploded, perspective view of a cover connector and an end portion of an arm according to an aspect of this disclosure;

FIG. 8B is a perspective view of the cover connector of FIG. 8A coupled to the end portion of the arm of FIG. 8A;

FIG. 8C is a perspective view of a portion of a chair cover coupled to the cover connector and the end portion of the arm of FIG. 8B;

FIG. 9A is an exploded, perspective view of a cover connector and an end portion of an arm according to another aspect of this disclosure;

FIG. 9B is a perspective view of the cover connector of FIG. 9A coupled to the end portion of the arm of FIG. 9A;

FIG. 9C is a perspective view of a portion of a chair cover coupled to the cover connector and the end portion of the arm of FIG. 9B; and

FIG. 10 is a flow diagram illustrating a method of manufacturing a collapsible chair according to an aspect of this disclosure.

DETAILED DESCRIPTION

Aspects of this disclosure are now described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. In the drawings and in the description that follows, terms such as front, rear, upper, lower, top, bottom, and similar directional terms are used simply for convenience of description and are not intended to limit the disclosure. In the following description, well-known functions or constructions are not described in detail to avoid obscuring this disclosure in unnecessary detail.

This disclosure is directed to robust collapsible chairs that are easy to manufacture and easy to set up. As illustrated in FIGS. 1A–1D, the chair frame 100 includes two hub assemblies: a first hub assembly 110a coupled to one end portion of a center axle 105 (which may also be referred to as a crossbar) and a second hub assembly 110b coupled to the other end portion of the center axle 105. The chair frame 100 also includes a first pair of

legs

103a, 104a coupled to a first hub assembly 110a and a second pair of

legs

103b, 104b coupled to the second hub assembly 110b. The collapsible chair also includes first and second front arms or

front seat arms

102a, 102b coupled to the first and

second hub assemblies

110a, 110b, respectively, and first and second back arms or back

rest arms

101a, 101b also coupled to first and

second hub assemblies

110a, 110b, respectively.

The

front arms

102a, 102b and

back arms

101a, 101b are designed to support a seat and back rest assembly, which may be coupled to end portions of the

front arms

102a, 102b and the

back arms

101a, 101b. Each of the

back arms

101a, 101b may include a first

back arm portion

111a, 111b, which is coupled to a

hub assembly

110a, 110b, and a second

back arm portion

112a, 112b. The first back arm portion 111a and the second back arm portion 112a are rotatably coupled to each other by a joint member 113a. Specifically, an end portion of the first back arm portion 111a is rotatably coupled to the joint member 113a via a pin 114a (e.g., the pin 114a passes through an aperture in an end portion of the first back arm portion 111a, and the end portions of the pin 114a attach to respective sides of the U-shaped joint member 113a) . An end portion of the second back arm portion 112a is rotatably to the joint member 113a via a pin 115a. The first back arm portion 111b and the second back arm portion 112b of the second back arm 101b are also rotatably coupled to each other via a joint member 113b and

pins

114b, 115b. The

joint members

113a, 113b may include detents protruding from the inner surfaces of the walls of the

joint members

113a, 113b. The detents may hold or lock the end portions of the first and second

back arm portions

111a, 111b, 112a, 112b in an extended state.

As illustrated in FIG. 1B, the

front arms

102a, 102b may be rotated in the directions shown by

arrows

122a, 122b towards a closed or collapsed state or position such that the

front arms

102a, 102b are parallel to or substantially parallel to the center axle 105. Similarly, the

front legs

103a, 103b may be rotated in the directions shown by

arrows

123a, 123b towards a closed or collapsed state or position such that the

front legs

103a, 103b are parallel to or substantially parallel to the center axle 105. In aspects, movement or rotation of the first front arm 102a and the first front leg 103a are mechanically linked to each via a rack and pinion assembly of the first hub assembly 110a. Thus, a force applied to the first front arm 102a to rotate the first front arm 102a towards a closed state in the direction of the arrow 122a would cause the first front leg 103a to rotate towards a closed state without any force being applied to the first front leg 103a. Movement or rotation of the second front arm 102b and the second front leg 103b are likewise mechanically linked to each via a rack and pinion assembly of the second hub assembly 110b.

As the

front arms

102a, 102b and the

front legs

103a, 103b rotate from an open state towards a closed state according to the

arrows

122a, 122b, 123a, 123b, the first and

second hub assemblies

110a, 110b rotate about respective end portions of the center axle 105 in opposite directions so that when the

front arms

102a, 102b and the

front legs

103a, 103b approach near to the center axle 105, the first front arm 102a and the first front leg 103a interleave with the second front arm 102b and the second front leg 103b. Consequently, the chair frame 100 in its collapsed state is compact.

As illustrated in FIGS. 1A and 1B, chair cover connectors 106 may be used to couple portions of a chair cover, e.g., the chair cover 702 of FIG. 7, to end portions of the

back arms

101a, 101b and the

front arms

102a, 102b. Before the chair cover connectors 106 are coupled to the end portions of the

back arms

101a, 101b and the

front arms

102a, 102b, as shown in FIG. 1A, straps (not shown) coupled to suitable portions of the back side of the chair cover may be placed between the male connector and the strap retaining member of respective chair cover connectors 106. Once a strap is placed between the male connector and the strap retaining member, the male connector is mated with a hollow end portion of one of the

back arms

101a, 101b or

front arms

102a, 102b, as illustrated in FIG. 1B, thereby preventing the strap from disconnecting from the chair cover connector 106.

As illustrated in FIG. 1C, the hub assembly 110a may be designed such that the angle 108 between the backrest arm 101a and the rear leg 104a is greater than the angle 107 between the seat arm 102a and the front leg 103a.

Referring now to FIG. 1D, the second

back arm portions

112a, 112b can rotate with respect to the first

back arm portions

111a, 111b according to the

arrows

125a, 125b, respectively. Specifically, for example, as the second back arm portion 112a rotates towards the first back arm portion 111a in a clockwise direction, either or both of the following movements may occur: (1) the second back arm portion 112a rotates about pin 115a with respect to the joint member 113a, and (2) the joint member 113a rotates about pin 114a with respect to the first back arm portion 111a. Thus, in a closed state of the first back arm 101a, both the first back arm portion 111a and the second back arm portion 112a are perpendicular to or substantially perpendicular to the first joint member 113a. Once the first and second

back arms

101a, 101b are in a closed state, the first and second

back arms

101a, 101b may be rotated in the direction indicated by

arrows

121a, 121b.

The first back arm 101a and the first back leg 104a are mechanically linked to each other and to the first front arm 102a and the first front leg 103a via the rack and pinion assembly of the first hub assembly 110a. Similarly, the second back arm 101b and the second back leg 104b are mechanically linked to each other and to the second front arm 102b and the second front leg 103b via the rack and pinion assembly of the second hub assembly 110b. As illustrated in FIG. 1D, the

back arms

101a, 101b and the

back legs

104a, 104b can rotate from an open state to a closed state according to the

arrows

122a, 122b, 123a, 123b, such that the

back arms

101a, 101b and the

back legs

104a, 104b are substantially parallel to the center axle 105 in the closed state.

FIGS. 2A and 2C show inner views of the hub assembly 110a of FIGS. 1A–1D and end portions of the

arms

101a, 102a and

legs

103a, 104a coupled to the hub assembly 110a according to an aspect of this disclosure. The

arms

101a, 102a and

legs

103a, 104a are illustrated as round tubular structures, but other aspects of this disclosure may include square, rectangular, or other-shaped tubular structures. The

arms

101a, 102a and

legs

103a, 104a are rotatably coupled to a hub housing 210 of the hub assembly 110a via pins 205. In other aspects, the pins 205 may be replaced with another fastener (e.g., rivets, bolts, etc. ) suitable for coupling the

arms

101a, 102a and

legs

103a, 104a to the hub housing 210 and allowing the

arms

101a, 102a and

legs

103a, 104a to rotate with respect to the hub housing 210. The hub assembly 110a uses a rack and pinion design to mechanically couple or link the

arms

101a, 102a and

legs

103a, 104a to each other. In particular, the gears or

pinions

201a, 202a, 203a, 204a at the end portions of the

arms

101a, 102a and

legs

103a, 104a, respectively, work simultaneously on the rack (not shown) and are dependent on each other when opening or closing the

arms

101a, 102a and

legs

103a, 104a. The

pinions

201a, 202a, 203a, 204a interface or mesh with corresponding arrays of teeth on various faces or sides of a rack (as illustrated in FIG. 3A) .

As shown in FIG. 2B, the hub assembly 110a includes a handle 215 to disengage all

arms

101a, 102a and

legs

103a, 104a in the open position or state. When a user pulls the handle 215 (in a direction out of the page) , a locking mechanism of the hub assembly 110a is unlocked, allowing the

arms

101a, 102a and

legs

103a, 104a of the chair to fold or collapse into each other (in a direction into the page) to collapse the chair. As illustrated in FIG. 2D, the hub assembly 110a includes an inner hub cap 220 that attaches to the hub housing 210. The inner hub cap 220 acts as both a structural feature and a cover that protects the

pinions

201a, 202a, 203a, 204a.

FIGS. 3A and 3B show the various features of the hub assembly 110b and how the hub assembly 110b couples to the

arms

101b, 102b and

legs

103b, 104b (also referred to as pinion axles) , and to the center axle 105 (also referred to as the center axle) . The hub assembly 110b includes a hub housing 210 and pinion arms or arm connectors, e.g., pinion arm 301, that is rotatably coupled between pairs of fin members, e.g.,

fin members

331a, 331b of the hub housing 210 by a pin, e.g., pin 321. An end portion of each pinion arm, e.g., pinion arm 301, connects to a pinion axle, e.g., backrest arm 101b. For example, an end portion of a pinion arm, e.g., pinion arm 301, may be a round tubular structure having a smaller diameter than an end portion of a round tubular structure of a pinion axle, e.g., backrest arm 101b, such that the end portion of the pinion arm, e.g., pinion arm 301, can fit within the end portion of the pinion axle, e.g., backrest arm 101b. The end portion of each pinion arm 301 may be fixedly coupled to the end portion of each pinion axle by one or more rivets, a suitable glue, or by welding the end portions together.

The hub assembly 110b further includes a rack member 340, which is fixedly coupled to an inside portion of the hub housing 210, and a crossbar or center axle connector 320, which connects to one of the end portions of the crossbar or center axle 105. In aspects, the rack member 340 simultaneously moves in a radial and longitudinal direction with respect to the center axle connector 320 when the arms and

legs

101b, 102b, 103b, 104b are opened or closed. The hub assembly 110b further includes a locking mechanism for locking the

arms

101b, 102b and the

legs

103b, 104b.

The locking mechanism includes a handle 215 (which may also be referred to as a pull handle or locking handle) , a locking housing 315, and a retaining ring 317. The locking housing 315 includes tabs, e.g., locking tabs 311, which mate with corresponding locking channels, e.g., locking channels 312, in each of the pinion arms, when the

arms

101b, 102b and

legs

103b, 104b are in the open state. The locking housing 315 is connected to the center axle connector 320 by a bolt 305, which passes through an interior portion of the center axle connector 320 and the spring 310 and attaches to protrusion 316 of the locking housing 315. Thus, when the handle 215 is pulled, the locking housing 315 and the center axle 105 move together and the spring 310 is compressed. While the handle 215 is being pulled, the

arms

101b, 102b and

legs

103b, 104b may be moved to their open state. Then, when the handle 215 is released, the spring 310 exerts a force to bring the locking housing 315 towards the hub housing 210 and the locking tabs 311 engage or mate with corresponding locking channels 312.

As shown in FIGS. 3A, 3B, and 4, the center axle connector 320 connects with the center axle 105. An end portion of the center axle 105 may be hollow such that the end portion of the center axle 105 mates with an end portion of the center axle connector 320. When the center axle connector 320 is mated with the center axle 105, the end portion of the center axle 105 may be in contact with the ridge 405. The end portion of the center axle 105 may include apertures (not shown) on opposite sides of the end portion of the center axle 105 that align with apertures 408 on opposite sides of the center axle connector 320. In this configuration, the pin 308 may pass through the apertures in the end portion of the center axle 105 and the apertures 408 in the center axle connector 320 to fix the center axle connector 320 to the center axle 105. The pin 308 may be press fit through the apertures and may have a length such that the end portions of the pin 308 are flush with the outer surface of the center axle 105. In other aspects, the center axle connector 320 may be fastened to the end portion of the center axle 105 by using glue, by interference or friction fitting the center axle connector 320 into the center axle 105, or by using any other suitable method for fixedly coupling or fastening the center axle connector 320 to the end portion of the center axle 105.

The center axle connector 320 includes grooves 442, which may be linear (e.g., a diagonal groove) or nonlinear (e.g., a helical or curved groove) , that engage or mate with corresponding ridges 342 (as illustrated in FIG. 3B) that extend from an inner surface of the rack member 340. As the rack member 340 moves longitudinally with respect to the center axle connector 320, the grooves 442 guide the ridges 342 to cause the rack member 340 to rotate. In other aspects, the grooves 442 may be a shape other than helical or diagonal that causes the rack member to rotate with respect to the center axle 105. In some aspects, the chair of this disclosure uses identical hub assemblies, which means that the rack member 340 and the corresponding two

hub assemblies

110a, 110b, which are fixedly coupled to the rack member 340, rotate in opposite directions, thus causing the

arms

101a, 101b, 102a, 102b and

legs

103a, 103b, 104a, 104b on opposite sides of the center axle 105 to interleave with each other as the

arms

101a, 101b, 102a, 102b and

legs

103a, 103b, 104a, 104b collapse into each other.

FIGS. 5A and 5B show an aspect of the hub housing 210. The hub housing 210 includes pairs of

fin members

331a, 331b that define an arm channel 531. The

fin members

331a, 331b each include a pinion axle aperture 521 in which end portions of a pinion axle or pin (e.g., pin 321 of FIG. 3A) are disposed. The center portion of the pinion axles extend across the arm channels 531. Each arm channel 531 is configured to receive a pinion arm (e.g., pinion arm 301 of FIG. 3A) , which is rotatably coupled to the hub housing 210 by a pinion axle that extends through a pair of pinion axle apertures 521 and an aperture (e.g., aperture 322 of FIG. 3A) in the pinion arm (e.g., pinion arm 301) . Each arm channel 531 may include detents (not shown) to hold the pinion axles in place when the pinion axles are in the closed position. The detents may be sized to obtain a proper balance between giving a user that ability to easily overcome the detents when opening the chair frame 100 and maintaining the chair frame 100 in a closed state when the user transports the chair frame 100.

As illustrated in FIG. 5A, the hub housing 210 also includes open slots 515 designed for receiving the locking housing 315 including the locking tabs 311 and a center axle aperture 520, through which the center axle connector 320 extends. As illustrated in FIG. 5B, the hub housing 210 further includes multiple ridges 544 formed at the base of pairs of

fin members

331a, 331b. The ridges 544 mate with corresponding grooves or channels 344 (FIGS. 3A and 3B) on the outer portion of the rack member 340 and thereby fixedly couple the hub housing 210 to the rack member 340 such that the rack member 340 and the hub housing 210 rotate together.

As illustrated in FIGS. 6A–6D, each of the pinion arms 301 includes a gear or pinion 601 on one side and a locking channel 312 on an opposite side. When each of the locking tabs 311 of the locking housing 315 engages or mates with a corresponding locking channel 312, the pinion arms 301 are locked in the open position. When a user pulls outward on the handle 215, each of the locking tabs 311 disengages from a corresponding locking channel 312, thus allowing the pinion arm 301 to rotate towards the closed or collapsed position or state. As the pinion arms 301 rotate towards the collapsed position, the pinions 601 rotate counterclockwise, thus causing the rack member 340 to move in a longitudinal direction towards the locking housing 315. As the rack member 340 moves towards the locking housing 315, the grooves 442 of the center axle connector 320 cause the rack member 340 to rotate clockwise.

FIG. 7 illustrates an aspect of a compact, collapsible chair 700. The collapsible chair 700 includes the chair frame 100 described herein and a chair cover 702 coupled to the chair frame 100. The chair cover 702, which may be made of a fabric, such as a nylon fabric, or any other suitable material for covering the chair frame 100 to provide a comfortable seat for the user, may attach to end portions of the

arms

101a, 101b, 102a, 102b. The chair 600 also includes feet, e.g.,

feet

703a, 703b, 704a, coupled to respective end portions of corresponding legs, e.g.,

legs

103a, 103b, 104a (a foot is also attached to an end portion of a fourth leg (not shown) ) . The feet, e.g.,

feet

703a, 703b, 704a, may be made of plastic, rubber, or any other material suitable for, among other things, providing stable footing and protecting the surface on which the collapsible chair 700 is placed. The feet may also be designed to be pressure fitted onto the end portions of the legs, e.g.,

legs

103a, 103b, 104a.

FIGS. 8A–8C illustrate a cover connector 810 that may be used to attach the chair cover 702 to end portions of the

arms

101a, 101b, 102a, 102b according to an aspect of this disclosure. FIG. 8A shows a cover connector 810 and an end portion 820 of an arm, which may be any one of

arms

101a, 101b, 102a, 102b. The cover connector 810 includes an end portion 812 (which, for example, may be referred to as a cap) , a male member 814, first and

second ridges

811, 815, a groove 813, and a protrusion 816 protruding from the second ridge 815. The male member 814 is configured to be interference-fitted within the hollow end portion 820 of the arm as illustrated in FIG. 8B. The male member 814 may be finned (with any suitable number of fins) , cylindrical, a combination of finned and cylindrical (as illustrated in FIG. 8A) , or any shape suitable for interference-fitting the male member 814 within the hollow end portion 820.

The end portion 820 of the arm may include an aperture (not shown) that mates with the protrusion 816 when the cover connector 810 is coupled to the end portion 820 of the arm to prevent the cover connector 810 from being removed from the end portion 820 of the arm. Alternatively, the protrusion 816 may be replaced by a screw, a pin, or other suitable fastener that passes through the second ridge 815 and the end portion 820 of the arm to fasten the cover connector 810 to the end portion 820 of the arm.

As shown in FIGS. 8B and 8C, when the cover connector 810 is coupled to the end portion 820 of the arm, the first and

second ridges

811, 815 and the groove 813 form an aperture 825 through which a strap 836 attached at two locations on a cover portion 832 (e.g., a portion of the chair cover 702) passes such that the cover portion 832 is coupled to the end portion 820 of the arm. The length of the groove 813 may be sized slightly larger than the width of the strap 836 such that the first and

second ridges

811, 815 limit movement of the strap 836. The first and

second ridges

811, 815 may include a curved surface that conforms to the curved surface of the end portion 820 of the arm. A pocket 834 or other suitable structure for receiving and coupling the end portion 812 of the cover connector 810 to the cover portion 832 may be attached to or form part of the cover portion 832.

FIGS. 9A–9C illustrate a cover connector 910 that may be used to attach the chair cover 702 to end portions of the

arms

101a, 101b, 102a, 102b according to another aspect of this disclosure. FIG. 9A shows a cover connector 910 and the end portion 820 of an arm. The cover connector 910 includes an end portion 912, a male member 914, a bridge member 911 coupled to the end portion 912, and an annular member 915 coupled to the bridge member 911. The male member 914 may be configured to be interference-fitted into the hollow end portion 820 of the arm as illustrated in FIG. 9B.

The male member 914 may be finned (with any suitable number of fins) , cylindrical, a combination of finned and cylindrical (as illustrated in FIG. 9A) , or any shape suitable for interference-fitting the male member 914 within the hollow end portion 820. The end portion 820 of the arm may include an aperture (not shown) that aligns with the aperture 917 when the cover connector 910 is coupled to the end portion 820 of the arm. A screw, pin, or any other suitable fastener may be passed through the aperture 917 and the end portion 820 of the arm to prevent the cover connector 810 from being removed from the end portion 820 of the arm.

As shown in FIGS. 9B and 9C, when the cover connector 910 is coupled to the end portion 820 of the arm, the end portion 912, the bridge member 911, and the annular member 915 form an aperture 925 through which a strap 936 attached at two locations on a cover portion 932 passes such that the cover portion 932 is coupled to the end portion 820 of the arm. The length of the aperture 925 may be sized slightly larger than the width of the strap 936 such that the end portion 912 of the cover connector 910 and the annular member 915 limit movement of the strap 936. A pocket 934 or other suitable structure for receiving and coupling the end portion 912 of the cover connector 810 to the cover portion 832 may be attached to or form part of the cover portion 932.

FIG. 10 is a flow diagram illustrating a method of manufacturing 1000 a collapsible chair according to an aspect of this disclosure. At block 1002, a hollow rack member is fixed to an inner portion of a hub housing. At block 1004, pinion arms are disposed in arm channels defined by pairs of fin members, respectively, of the hub housing such that the pinions of the pinion arms mesh with gear teeth on different portions of the hollow rack member. At block 1006, axles are inserted through respective apertures of the pairs of fin members and the pinion arms. At block 1008, a center axle connector is passed through the hollow rack so that interior ridges of the hollow rack engage with exterior grooves of the center axle connector. At block 1010, a bolt is passed through the center axle connecter and a spring, and, at block 1012, the bolt is coupled to a locking housing. At block 1014, arms are coupled to a portion of the pinion arms and, at block 1016, legs are coupled to the remaining portion of the pinion arms. Then, at block 1018, a center axle is coupled to the center axle connector.

While several aspects of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular aspects. For example, the pins described herein may be replaced by rivets, bolts, or any suitable structure for rotatably fixing two components to each other.

Claims

A collapsible chair, comprising:

a crossbar including a first end portion and a second end portion, the first and second end portions each including at least one lengthwise groove;

a first hub and a second hub rotatably coupled to the first end portion and the second end portion, respectively, the first hub and the second hub each including a rack gear having an inner portion and an outer portion, the inner portion including at least one ridge that mates with the least one lengthwise groove, the outer portion including gear teeth; and

two arms and two legs rotatably coupled to each of the first hub and the second hub, the two arms and the two legs each including end portions with a pinion gear that meshes with a portion of the teeth of the rack gear,

wherein the first hub and the second hub rotate about the crossbar in opposite directions as the arms and legs are rotated towards the crossbar.
The collapsible chair of claim 1, wherein the at least one lengthwise groove is a linear or nonlinear groove.
The collapsible chair of claim 2, wherein the nonlinear groove is a helical or curved groove.
The collapsible chair of claim 1, further comprising a locking housing coupled to each of the first and second end portions of the crossbar at an outer side of each of the first and second hubs, respectively,

wherein the locking housing includes tabs, and

wherein the end portions of the two arms and two legs include locking channels that mate with the tabs.
The collapsible chair of claim 1, wherein the crossbar includes a center portion and the first and second end portions of the crossbar are first and second crossbar connectors, respectively, which are coupled to the center portion of the crossbar.
The collapsible chair of claim 1, wherein a portion of each of the first and second crossbar connectors pass through a hollow portion of the rack gear and is coupled to the locking housing of each of the first and second hubs.
The collapsible chair of claim 6, further comprising an elastic member coupling the first and second end portions of the crossbar to the first and second locking housings, respectively.
The collapsible chair of claim 7, wherein the elastic member is a spring or a rubber band.
The collapsible chair of claim 8, wherein the spring is a leaf spring.
The collapsible chair of claim 1, wherein two arms are backrest arms, each of which includes a first arm and a second arm including end portions that are rotatably coupled to each other such that the first arm and the second arm can be folded together.
The collapsible chair of claim 1, further comprising a chair cover configured to couple to end portions of the arms.
The collapsible chair of claim 11, further comprising a plurality chair cover connectors, each chair cover connector configured to couple between an end portion of each arm and a portion of the chair cover.
The collapsible chair of claim 12, wherein the end portion of each arm is hollow, and

wherein each chair cover connector includes:

a cap;

a male member coupled to the cap and configured to mate with the end portion of each arm,

a retaining member coupled to the bridge member and configured to couple to each arm; and

a bridge member coupled between the cap and the retaining member, the bridge member and a portion of each arm forming an aperture configured to receive a strap coupled to the chair cover.
The collapsible chair of claim 13, wherein the retaining member is an annular member configured to fit around each arm.
The collapsible chair of claim 13, wherein the male member is configured to be interference-fitted into the end portion of each arm.
A hub assembly of a collapsible chair, comprising:

a hub housing;

a hollow rack member including inner and outer surfaces, at least one ridge protruding from the inner surface and configured to mate with and translate along at least one groove of a center axle to cause the hub housing to rotate with respect to the center axle, the outer surface including a plurality of teeth; and

a plurality of pinion arms rotatably coupled to the hub housing and including a respective plurality of pinions, which mesh with different portions of the plurality of teeth of the hollow rack member,

wherein the plurality of pinion arms, when rotated towards the center axle, drive the hollow rack member along a length of the center axle.
A collapsible chair, comprising:

a center axle having a first end portion and a second end portion, the first and second end portions each including at least one lengthwise groove;

a first hub and a second hub rotatably coupled to the first end portion and the second end portion, respectively, the first hub and the second hub each including a hollow rack having an interior portion and an exterior portion, the interior portion including at least one ridge that mates with a least one helical groove, the exterior portion including gear teeth; and

a plurality of pinion axles rotatably coupled to each of the first hub and the second hub, the plurality of pinion axles having respective end portions with a pinion gear that mates with the gear teeth,

wherein the first hub and the second hub rotate about the center axle in opposite directions when the plurality of pinion axles are rotated towards the center axle.
A method of manufacturing a collapsible chair, comprising:

fixing a hollow rack member to an inner portion of a hub housing;

disposing a plurality of pinion arms in a plurality of arm channels defined by a plurality of pairs of fin members, respectively, of the hub housing so that the pinions of the plurality of pinion arms mesh with gear teeth on different portions of the hollow rack member;

inserting a plurality of axles through respective apertures of the plurality of pairs of fin members and the plurality of pinion arms;

passing a center axle connector through the hollow rack so that interior ridges of the hollow rack engage with exterior grooves of the center axle connector;

passing a bolt through the center axle connecter and a spring;

coupling the bolt to a locking housing;

coupling a plurality of arms to a portion of the plurality of pinion arms;

coupling a plurality of legs to the remaining portion of the plurality of pinion arms; and

coupling a center axle to the center axle connector.