Support ring for holding a fabric seat on inclined frame tube

Information

  • Patent Grant
  • 6241311
  • Patent Number
    6,241,311
  • Date Filed
    Thursday, July 29, 1999
    25 years ago
  • Date Issued
    Tuesday, June 5, 2001
    23 years ago
Abstract
A support ring for holding a fabric seat on an inclined frame tube of a portable chair frame allows the support ring to rest horizontally on the inclined frame tube so as to enable the fabric seat also resting horizontally on the chair frame. The support ring has a supporting hole contributed by two semi-circular portions and an intermediate portion extended between the two semi-circular portions. Each of the semi-circular portions has a diameter equal to or slightly larger than a diameter of the inclined frame tube. The intermediate portion also has a width equal to the diameter of the semi-circular portion. When the inclined frame tube fittingly passes through the supporting hole and is supported inclinedly with the horizontal, the support ring can be horizontally mounted on the inclined frame tube while a lower half of the frame tube resting on an upper edge of one of the semi-circular portion of the supporting hole and an upper half of the frame tube supporting by a lower edge of the another semi-circular portion of the supporting hole. Therefore, the fabric seat can be mounted horizontally on the chair frame and the downwardly force applied on the fabric seat can be evenly distributed and supported around the support ring.
Description




FIELD OF THE PRESENT INVENTION




The present invention relates to fabric made portable seat products, and more particularly, to a support ring for holding a fabric seat on an inclined chair frame tube.




BACKGROUND OF THE PRESENT INVENTION




Portable chair generally consists of a collapsible chair frame constructed by metal tubes, and a chair seat made of durable fabric.





FIG. 1

illustrates a type of portable chair which includes a chair frame A


1


which is constructed by a set of interlocking tubes A


11


to pvoide a back frame section A


2


and a seat frame section A


3


for supporting a fabric seat B


1


. The interlocking tubes A


11


of the seat frame A


1


are often arranged in inclined manner so that the chair frame A


1


can be easily opened to proivde a rigid cross-support for use and be folded up for storage.




The conventional method of attaching the fabric seat B


1


to the chair frame A


1


is to affix an upper end B


2


of the fabric seat B


1


to a top end of the back frame section A


2


and to have two tube placement holes B


11


provided at two front corners of the fabric seat B


1


for mounting a front end B


3


of the fabric seat B


1


on two the seat frame. Each of the placement holes The conventional fabric seat is attached to the seat frame by slipping the tube placement holes over the inclined frame tubes of the seat frame portion of the chair. The seat can then be hooked over the top of the back frame to secure the back of the fabric seat to the frame. This means that at least two tube placement holes on the front portion of the fabric seat for attaching the fabric seat to the front portion of a seat frame are needed for the conventional fabric seat in order to attach the fabric seat to a seat frame.




All typical frame tubes A


11


, including the two front frame tubes A


11




a,


are cylindrical hollow tube and the tube placement holes B


11


of the conventional fabric seat B


1


are cut in circular shape and to the size of the frame tube A


11


as if the fabric seat B


1


were resting perpendicular to the frame tube A


11


. This allows the tube placement hole B


11


of the fabric seat B


1


to slide onto the inclined frame tube A


11


easily and snugly. This conventional design, however, has inherent problems when the chair is used. Since the two front frame tube A


11




a


are supported inclinedly and pivotally in cross manner but not in vertical manner, an individual sitting down on the fabric seat B


1


causes stress to the lining of the tube placement hole B


11


of the fabric seat B


1


. This causes the tube placement hole B


11


to be stretched and misshapen, or worse, torn open, as a pulling pressure is applied to the lining of the tube placement holes B


11


as an individual sits on the fabric seat B


1


.




Conventionally, in order to reinforce the structural integrity of the tube placement hole B


11


, a circular support ring made of a rigid material, such as metal or hard plastic, can be mounted on the placed within the tube placement hole.




However, since the support ring lining of the tube placement hole B


11


is also cylindrical and just wider then the width of frame tube, it merely shifts the point of stress on the fabric seat B


1


. The circular support ring merely sits perpendicularly to an axis of the frame tube B


11


. In this situation, if an individual sits down, an angle is created on the fabric seat B


1


from the downward pulling force on the fabric seat B


1


at the point where the edge of the support ring ends. A person's weight causes the fabric seat B


1


to be pulled away from the edge of the support ring. Therefore, the fabric seat B


1


at the edge of the support ring is pulled from a stress created at the edge of the support ring. At the same time, the ring itself causes an opposite downward pulling force on the fabric seat B


1


at the same stress point. As a result, two things occur. First, the fabric seat B


1


will be distorted at the edge of the support ring, creating a pointed ridge at the edge of the support ring. Second, a stress point is created at edge of the support ring where the angle is created.




In other words, the stress on the fabric seat B


1


has simply been transferred from the lining of the tube placement hole B


11


to a point just off the tube placement hole B


11


. The stress created will then cause a tear, not at the tube placement hole B


11


, but along the edge of the support ring. Although additional lining layers B


12


may be added to the corners of the fabric seat B


1


around the tube placement hole B


11


to delay the tearing effect, ultimately the stress will cause the fabric seat B


1


to tear. Also, the fabric will be permanently misshapen at the stress point over a period of continued use.




SUMMARY OF THE PRESENT INVENTION




A main object of the present invention is to provide a support ring for the lining of a tube placement hole of a fabric seat for attaching the fabric seat to tube of a chair frame by sliding the support ring over an respective inclined frame tube of the chair frame in a manner as to allow the support ring to rest horizontally on the inclined frame tube so as to enable the fabric seat also resting horizontally on the chair frame.




Another object of the present invention is to provide a support ring for a fabric seat that can evenly distribute the stress around the support ring so as to minimize the deterioration of the tube placement hole of the fabric seat as the portable chair is used.




Another object of the present invention is to provide a support ring for a fabric seat for attaching the fabric seat to a chair frame that limits damage to the area around the tube placement hole of the fabric seat as the portable chair is used.




Another object of the present invention is to provide a support ring that reduces the horizontal strain on the tube placement hole from being pulled against the inclined frame tube by transferring some of the force to vertical pressure by the support ring against the inclined frame tube.




Another object of the present invention is to provide a support ring for a fabric seat, which slides onto the respective inclined frame tube in such a manner as to allow an individual to sit on the fabric seat without distorting the shape of the fabric seat.




Accordingly, in order to accomplish the above objects, the present invention provides a support ring provided on a corner portion of a fabric seat for holding the fabric seat on an inclined frame tube of a chair frame, wherein the inclined frame tube is a round tube arranged to be inclined with respect to the horizontally supported fabric seat. The support ring has a supporting hole contributed by two semi-circular portions and an intermediate portion extended between the two semi-circular portions. Each of the semi-circular portions has a diameter equal to or slightly larger than a diameter of the inclined frame tube. The intermediate portion also has a width equal to the diameter of the semi-circular portion. When the inclined frame tube fittingly passes through the supporting hole and is supported inclinedly with the horizontal, the support ring can be horizontally mounted on the inclined frame tube while a lower half of the frame tube resting on an upper edge of one of the semi-circular portion of the supporting hole and an upper half of the frame tube supporting by a lower edge of the another semi-circular portion of the supporting hole. Therefore, the fabric seat can be mounted horizontally on the chair frame and the downwardly force applied on the fabric seat can be evenly distributed and supported around the support ring.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view illustrating a conventional collapsible chair.





FIG. 2

is a perspective view illustrating part of a collapsible chair comprising a pair of support rings for holding a fabric seat on an inclined chair frame tube according to a preferred embodiment of the present invention.





FIG. 3

is an exploded perspective view of the support ring adapted to be mounted on a fabric seat according to the above-preferred embodiment of the present invention.





FIG. 4

is a sectional side view of the support ring for holding a fabric seat on an inclined chair frame tube according to the above-preferred embodiment of the present invention.





FIG. 5

is a schematic top view of the support ring having the inclined frame tube passing through according to the above-preferred embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Referring to

FIGS. 2 and 3

with reference to

FIG. 1

, a collapsible portable chair comprises a fabric seat


10


having two tube placement holes


111


formed at two corners thereof for two inclined frame tubes


70


to penetrate therethrough respectively for supporting the fabric seat


10


in position.




A pair of reinforcing patches


33


made of strong but flexible textile, such as leather, is integrally stitched to two corners of a top surface of the fabric seat


10


around the tube placement hole


111


for reinforcing the structural integrity of the tube placement hole


111


.




Referring to

FIGS. 2

to


5


, the present invention provides a support ring


30


for reinforcing the tube placement hole


111


and adding stiffness and durability to the tube placement hole


111


. As shown in

FIG. 3

, the support ring


30


comprises an oval upper ring member


31


and an oval lower ring member


32


. The upper ring member


31


and the lower ring member


32


of the support ring


30


each has a set of identical first and second curved end pieces


311


,


311


′,


321


,


321


′ and two identical side pieces


312


,


322


connecting the first and second end pieces.




As shown in

FIGS. 3 and 4

, the upper ring member


31


comprises a holding ring plate


3111


, a ring shaped shank


3112


integrally extended from an inner ring edge of the holding ring plate


3111


downwardly, and a bottom engaging rim


3113


integrally extended from the shank


3112


and adapted to bend outwardly to engage with the lower ring member


32


so as to form the support ring


30


and mount the support ring


30


around the tube placement hole


111


of the fabric seat


11


. The size and shape of the shank


3112


is preferable equal to or slightly smaller than the tube placement hole


111


of the fabric seat


10


.




The lower ring member


32


comprises an oval ring-shaped base plate


3211


having a central ring hole


3200


(as shown in

FIG. 3

) and an engagement ridge


3212


downwardly projected around the ring hole


3200


of base plate


3211


. The ring hole


3200


has a size and shape preferably equal to that of the tube placement hole


111


.




To mount the support ring


30


around the tube placement hole


111


of the fabric seat


10


, as shown in

FIGS. 3 and 4

, the lower ring member


32


is first to place underneath the tube placement hole


111


so as to align the tube placement hole


111


with the ring hole


3200


coaxially. Second, insert the shank


3112


downwardly through the tube placement hole


111


until the holding ring plate


3111


pressing on the area around the tube placement hole


111


of the reinforcing patch


33


and the engaging rim


3113


downwardly extending out of the lower ring member


32


. Finally, outwardly and radially bend the engaging rim


3113


to fold over the engagement ridge


3212


of the lower ring member


32


, as shown in

FIG. 4

, so as to firmly connect the upper ring member


31


with the lower ring member


32


together to form the support ring


30


and to secure the support ring


30


on the fabric seat


10


by mounting around the respective tube placement hole


111


on the fabric seat


10


, wherein a round edge around the tube placement hole


111


of the fabric seat is securely clamped between the upper ring member


31


and the lower ring member


32


by compressing the upper ring member


31


and the lower ring member


32


towards each other.




As shown in

FIGS. 2

to


5


, the support ring


30


mounted on a corner portion the fabric seat


10


according to the present invention is adapted for holding the fabric seat


10


on the inclined frame tube


70


of a chair frame, wherein the inclined frame tube


70


is a round tube arranged to be inclined with respect to the horizontally supported fabric seat


10


as shown in

FIGS. 2 and 4

. The support ring


30


has a supporting hole


300


contributed by two semi-circular portions


301


,


302


and an intermediate portion


303


extended between the two semi-circular portions


301


,


302


(as shown in FIG.


5


).




Each of the semi-circular portions


301


,


302


has a diameter equal to or slightly larger than a diameter of the inclined frame tube


70


. As shown in

FIGS. 4 and 5

, the intermediate portion


303


also has a width equal to the diameter of the semi-circular portion


301


,


302


. When the inclined frame tube


70


fittingly passes through the supporting hole and is supported inclinedly with respect to the horizontal, the support ring


30


is horizontally held on the inclined frame tube


70


while a lower half of the frame tube


71


resting on an upper edge


304


of one of the semi-circular portion


301


of the supporting hole


300


and an upper half


72


of the frame tube


70


supporting by a lower edge


305


of the another semi-circular portion


302


of the supporting hole


300


. So that the support ring


30


can be horizontally rested on a seat joint


80


which is riveted on the inclined frame tube


70


, as shown in

FIGS. 2

to


4


. Therefore, the fabric seat


10


can be mounted horizontally on the chair frame and the downwardly force applied on the fabric seat


10


can be evenly distributed and supported around the support ring


30


.




Accordingly, raised points near each support ring


30


and stress points along the edges of each support ring


30


are eliminated. The shape and size of the support ring


30


is the same shape and size as a cross-section of the inclined frame tube


70


, as shown in

FIG. 5

, so that the inclined frame tube


70


may only rotate between a vertical position and an inclined position as shown in FIG.


4


.




In view of above, the support ring


30


of the present invention can substantially achieve the following features:




1. The support ring


30


is adapted for the lining of the tube placement hole


111


of the fabric seat


10


for attaching the fabric seat


10


to the chair frame by sliding the support ring


30


over the respective inclined frame tube


70


of the chair frame in a manner as to allow the support ring


30


to rest horizontally on the inclined frame tube


70


so as to enable the fabric seat


10


also resting horizontally on the chair frame.




2. It can evenly distribute the stress around the support ring


30


so as to minimize the deterioration of the tube placement hole


111


of the fabric seat


10


as the portable chair is used.




3. It can limit damage to the area around the tube placement hole


111


of the fabric seat


10


as the portable chair is used.




4. It can reduce the horizontal strain on the tube placement hole


111


from being pulled against the inclined frame tube


70


by transferring some of the force to vertical pressure by the support ring


30


against the inclined frame tube


70


.



Claims
  • 1. A support ring mounted on a corner portion of a fabric seat for holding said fabric seat on an inclined frame tube of a chair frame, said support ring having a supporting hole contributed by two semi-circular portions and an intermediate portion extended between said two semi-circular portions, said intermediate portion having a width at least equal to a diameter of each of said semi-circular portions, thereby said supporting ring is adapted for said inclined frame tube passing therethrough for supporting said fabric seat inclinedly with respect to horizontal, and said support ring is arranged for horizontally holding on said inclined frame tube while a lower half of said frame tube resting on an upper edge of one of said semi-circular portion of said supporting hole and an upper half of said frame tube supporting below a lower edge of another said semi-circular portion of said supporting hole, so as to hold said fabric seat horizontally on said chair frame.
  • 2. The support ring as recited in claim 1 wherein said support ring is mounted on a tube placement hole formed at one of a front corner of said fabric seat.
  • 3. The support ring as recited in claim 2 wherein said support ring comprises an oval upper ring member and an oval lower ring member, wherein said upper ring member comprises a holding ring plate, a ring shaped shank integrally extended from an inner ring edge of said holding ring plate downwardly, and a bottom engaging rim integrally extended from said shank and adapted to bend outwardly to engage with said lower ring member so as to form said support ring and mount said support ring around said tube placement hole of said fabric seat.
  • 4. The support ring as recited in claim 3 wherein said lower ring member comprises an oval ring-shaped base plate having a central ring hole and an engagement ridge downwardly projected around said ring hole of said base plate, wherein said engaging rim, which is downwardly extended out of said lower ring member, is outwardly and radially bent to fold over said engagement ridge of said lower ring member so as to firmly connect said upper ring member with said lower ring member together to form said support ring and to secure said support ring on said fabric seat by mounting around said respective tube placement hole on said fabric seat, wherein a round edge around said tube placement hole of said fabric seat is securely clamped between said upper ring member and said lower ring member by compressing said upper ring member and said lower ring member towards each other.
  • 5. The support ring as recited in claim 2 wherein a reinforcing patch is stitched on said front corner of said fabric seat around said tube placement hole for reinforcing a structural integrity of said tube placement hole.
  • 6. The support ring as recited in claim 5 wherein said support ring comprises an oval upper ring member and an oval lower ring member, wherein said upper ring member comprises a holding ring plate, a ring shaped shank integrally extended from an inner ring edge of said holding ring plate downwardly, and a bottom engaging rim integrally extended from said shank and adapted to bend outwardly to engage with said lower ring member so as to form said support ring and mount said support ring around said tube placement hole of said fabric seat.
  • 7. The support ring as recited in claim 6 wherein said lower ring member comprises an oval ring-shaped base plate having a central ring hole and an engagement ridge downwardly projected around said ring hole of said base plate, wherein said engaging rim, which is downwardly extended out of said lower ring member, is outwardly and radially bent to fold over said engagement ridge of said lower ring member so as to firmly connect said upper ring member with said lower ring member together to form said support ring and to secure said support ring on said fabric seat by mounting around said respective tube placement hole on said fabric seat, wherein a round edge around said tube placement hole of said fabric seat is securely clamped between said upper ring member and said lower ring member by compressing said upper ring member and said lower ring member towards each other.
  • 8. The support ring as recited in claim 1 wherein said support ring comprises an oval upper ring member and an oval lower ring member, wherein said upper ring member comprises a holding ring plate, a ring shaped shank integrally extended from an inner ring edge of said holding ring plate downwardly, and a bottom engaging rim integrally extended from said shank and bent outwardly to engage with said lower ring member so as to form said support ring and mount said support ring on said corner portion of said fabric seat.
  • 9. The support ring as recited in claim 8 wherein said lower ring member comprises an oval ring-shaped base plate having a central ring hole and an engagement ridge downwardly projected around said ring hole of said base plate, wherein said engaging rim, which is downwardly extended out of said lower ring member, is outwardly and radially bent to fold over said engagement ridge of said lower ring member so as to firmly connect said upper ring member with said lower ring member together to form said support ring and to secure said support ring on said fabric seat by mounting around a tube placement hole provided on said corner portion of said fabric seat, wherein a round edge around said tube placement hole of said fabric seat is securely clamped between said upper ring member and said lower ring member by compressing said upper ring member and said lower ring member towards each other.
  • 10. A support ring mounted on a corner portion of a fabric seat wherein an inclined frame tube is arranged to be inclined with respect to said fabric seat for holding said fabric seat on said inclined frame tube, said support ring having a supporting hole contributed by two semi-circular portions and an intermediate portion extended between said two semi-circular portions, each of said semi-circular portions having a diameter at least equal to a diameter of said inclined frame tube, said intermediate portion also having a width at least equal to said diameter of said semi-circular portion, wherein when said inclined frame tube fittingly passes through said supporting hole and is supported inclinedly with respect to horizontal, said support ring is horizontally held on said inclined frame tube while a lower half of said frame tube resting on an upper edge of one of said semi-circular portion of said supporting hole and an upper half of said frame tube supporting below a lower edge of another said semi-circular portion of said supporting hole.
  • 11. The support ring as recited in claim 10 wherein said support ring is mounted on a tube placement hole formed at one of a front corner of said fabric seat.
  • 12. The support ring as recited in claim 11 wherein a reinforcing patch is stitched on said front corner of said fabric seat around said tube placement hole for reinforcing a structural integrity of said tube placement hole.
  • 13. The support ring as recited in claim 12 wherein said support ring comprises an oval upper ring member and an oval lower ring member, wherein said upper ring member comprises a holding ring plate, a ring shaped shank integrally extended from an inner ring edge of said holding ring plate downwardly, and a bottom engaging rim integrally extended from said shank and adapted to bend outwardly to engage with said lower ring member so as to form said support ring and mount said support ring around said tube placement hole of said fabric seat.
  • 14. The support ring as recited in claim 13 wherein said lower ring member comprises an oval ring-shaped base plate having a central ring hole and an engagement ridge downwardly projected around said ring hole of said base plate, wherein said engaging rim, which is downwardly extended out of said lower ring member, is outwardly and radially bent to fold over said engagement ridge of said lower ring member so as to firmly connect said upper ring member with said lower ring member together to form said support ring and to secure said support ring on said fabric seat by mounting around said respective tube placement hole on said fabric seat, wherein a round edge around said tube placement hole of said fabric seat is securely clamped between said upper ring member and said lower ring member by compressing said upper ring member and said lower ring member towards each other.
  • 15. The support ring as recited in claim 10 wherein said support ring comprises an oval upper ring member and an oval lower ring member, wherein said upper ring member comprises a holding ring plate, a ring shaped shank integrally extended from an inner ring edge of said holding ring plate downwardly, and a bottom engaging rim integrally extended from said shank and bent outwardly to engage with said lower ring member so as to form said support ring and mount said support ring on said corner portion of said fabric seat.
  • 16. The support ring as recited in claim 15 wherein said lower ring member comprises an oval ring-shaped base plate having a central ring hole and an engagement ridge downwardly projected around said ring hole of said base plate, wherein said engaging rim, which is downwardly extended out of said lower ring member, is outwardly and radially bent to fold over said engagement ridge of said lower ring member so as to firmly connect said upper ring member with said lower ring member together to form said support ring and to secure said support ring on said fabric seat by mounting around a tube placement hole provided on said corner portion of said fabric seat, wherein a round edge around said tube placement hole of said fabric seat is securely clamped between said upper ring member and said lower ring member by compressing said upper ring member and said lower ring member towards each other.
  • 17. The support ring as recited in claim 11 wherein said support ring comprises an oval upper ring member and an oval lower ring member, wherein said upper ring member comprises a holding ring plate, a ring shaped shank integrally extended from an inner ring edge of said holding ring plate downwardly, and a bottom engaging rim integrally extended from said shank and adapted to bend outwardly to engage with said lower ring member so as to form said support ring and mount said support ring around said tube placement hole of said fabric seat.
  • 18. The support ring as recited in claim 17 wherein said lower ring member comprises an oval ring-shaped base plate having a central ring hole and an engagement ridge downwardly projected around said ring hole of said base plate, wherein said engaging rim, which is downwardly extended out of said lower ring member, is outwardly and radially bent to fold over said engagement ridge of said lower ring member so as to firmly connect said upper ring member with said lower ring member together to form said support ring and to secure said support ring on said fabric seat by mounting around said respective tube placement hole on said fabric seat, wherein a round edge around said tube placement hole of said fabric seat is secured clamped between said upper ring member and said lower ring member by compressing said upper ring member and said lower ring member towards each other.
US Referenced Citations (5)
Number Name Date Kind
3512224 Newton May 1970
4890362 Odajima et al. Jan 1990
5975626 Aycock Nov 1999
5984406 Lee Nov 1999
6045177 Grace Apr 2000