초록 ▼

A frame element includes a first scissor including a first and a second strut pivotably connected to each other at a first pivot point, a second scissor including a third and a fourth strut pivotably connected to each other at a second pivot point, and a hub to which the first and the third strut ar

A frame element includes a first scissor including a first and a second strut pivotably connected to each other at a first pivot point, a second scissor including a third and a fourth strut pivotably connected to each other at a second pivot point, and a hub to which the first and the third strut are pivotably connected, the first and second scissors being pivotable about the hub between a closed position in which the first, second, third, and fourth struts are substantially parallel to one another and an open, locked position in which the first and third struts define a non-zero angle with each other and abutment portions of the second and fourth struts contact receiving portions of the third and first struts, respectively, and prevent the first and third struts from pivoting beyond the non-zero angle.

대표청구항 ▼

What is claimed is: 1. A frame element, comprising: a first scissor comprising a first and a second strut pivotably connected to each other at a first pivot point; a second scissor comprising a third and a fourth strut pivotably connected to each other at a second pivot point; and a hub to which th

What is claimed is: 1. A frame element, comprising: a first scissor comprising a first and a second strut pivotably connected to each other at a first pivot point; a second scissor comprising a third and a fourth strut pivotably connected to each other at a second pivot point; and a hub to which the first and the third strut are pivotably connected, the first and second scissors being pivotable about the hub between a closed position in which the first, second, third, and fourth struts are in a first substantially parallel relationship to one another and side-by-side, through an intermediate position in which the first and the third struts define a non-zero angle with each other and in which the second and fourth struts are substantially end-to-end and in a second substantially parallel relationship to each other and end-to-end, and to an open, locked position in which the first and third struts define the non-zero angle with each other, and the second and fourth struts define a second non-zero angle with each other and abutment portions of the second and fourth struts contact receiving portions of the third and first struts, respectively, and prevent the first and third struts from pivoting beyond the non-zero angle. 2. The frame element as set forth in claim 1, wherein the first and fourth struts are pivotable in a substantially common plane, and the second and third struts are pivotable in a substantially common plane. 3. The frame element as set forth in claim 2, wherein the abutment surfaces of the second and fourth struts are ends of the second and fourth struts. 4. The frame element as set forth in claim 3, further comprising a brace on the first and third struts proximate each receiving portion. 5. The frame element as set forth in claim 1, wherein each of the first, second, third, and fourth struts have first and second ends, the frame element comprising at least three hubs, the first ends of at least one of the first, second, third, and fourth struts being pivotably connected to at least one of the three hubs. 6. The frame element as set forth in claim 5, comprising a tension member extending between successive ones of each of the at least three hubs. 7. The frame element as set forth in claim 1, comprising a tension member associated with the first and the second scissor for retaining the first and the second scissor in the open, locked position. 8. The frame element as set forth in claim 1, wherein the first and second pivot points are parallel pivot axes. 9. The frame element as set forth in claim 1, comprising a third scissor comprising a fifth and a sixth strut, the fifth strut being pivotably connected to the hub and the sixth strut being pivotably connected to the second and fourth struts. 10. The frame element as set forth in claim 9, wherein the third scissor is substantially perpendicular to the first and second scissors when the first, second, and third scissors are in an open position. 11. A frame element, comprising: a first scissor comprising a first and a second strut pivotably connected to each other at a first pivot point; a second scissor comprising a third and a fourth strut pivotably connected to each other at a second pivot point; a hub to which the first and the third strut are pivotably connected, the first and second scissors being pivotable about the hub between a closed position in which the first, second, third, and fourth struts are substantially parallel to one another and an open, locked position in which the first and third struts define a non-zero angle with each other and abutment portions of the second and fourth struts contact receiving portions of the third and first struts, respectively, and prevent the first and third struts from pivoting beyond the non-zero angle, wherein each of the first, second, third, and fourth struts have first and second ends, the frame element comprising at least three hubs, the first ends of at least one of the first, second, third, and fourth struts being pivotably connected to at least one of the three hubs; and a tension member extending between successive ones of each of the at least three hubs, wherein the second and the fourth struts are pivotably connected to each other at pivot points intermediate the first and second pivot points and the abutment portions of the second and fourth struts. 12. The frame element as set forth in claim 11, wherein, in order to pivot the first and second scissors from the closed position to the open, locked position, the second and fourth struts are moved from a closed position in which they define a 0° angle with each other and in which the tension member is relaxed, to a transition position in which the second and fourth struts define a 180° with each other and the tension member is under tension, to the open, locked position in which the second and fourth struts define non-zero angle greater than 180° with each other and the tension member is under less tension than when the second and fourth struts are in the transition position. 13. The frame element as set forth in claim 12, wherein the tension member is elastic to permit the first and second scissors to move between the closed and the open positions. 14. The frame element as set forth in claim 13, wherein the first and second scissors are flexible to permit the first and second scissors to move between the closed and the open positions. 15. The frame element as set forth in claim 12, wherein the first and second scissors are flexible to permit the first and second scissors to move between the closed and the open positions. 16. The frame element as set forth in claim 12, wherein a distance between the first pivot point and a center of the hub is greater than a distance between the first pivot point and the intermediate pivot point. 17. A frame element, comprising: a first scissor comprising a first and a second strut pivotably connected to each other at a first pivot point; a second scissor comprising a third and a fourth strut pivotably connected to each other at a second pivot point; and a hub to which the first and the third strut are pivotably connected, the first and second scissors being pivotable about the hub between a closed position in which the first, second, third, and fourth struts are substantially parallel to one another and an open, locked position in which the first and third struts define a non-zero angle with each other and abutment portions of the second and fourth struts contact receiving portions of the third and first struts, respectively, and prevent the first and third struts from pivoting beyond the non-zero angle; and a tension member associated with the first and the second scissor for retaining the first and the second scissor in the open, locked position, wherein the second and the fourth struts are pivotably connected to each other at points intermediate the first and second pivot points and the abutment portions of the second and fourth struts. 18. The frame element as set forth in claim 17, wherein, in order to pivot the first and second scissors from the closed position to the open, locked position, the second and fourth struts are moved from a closed position in which they define a 0° angle with each other and in which the tension member is relaxed, to a transition position in which the second and fourth struts define a 180° with each other and the tension member is under tension, to the open, locked position in which the second and fourth struts define non-zero angle greater than 180° with each other and the tension member is under less tension than when the second and fourth struts are in the transition position. 19. A folding frame system, comprising: at least two frame elements, each frame element comprising a first scissor comprising a first and a second strut pivotably connected to each other at a first pivot point, a second scissor comprising a third and a fourth strut pivotably connected to each other at a second pivot point, and at least three hubs, each of the first, second, third, and fourth struts having first and second ends, the first ends of at least one of the first, second, third, and fourth struts being pivotably connected to at least one of the three hubs, the first and second scissors being pivotable about the hubs between a closed position in which the first, second, third, and fourth struts are in a first substantially parallel relationship to one another and side-by-side, through an intermediate position in which the first and the third struts define a non-zero angle with each other and in which the second and fourth struts are substantially end-to-end and in a second substantially parallel relationship to each other and end-to-end, and to an open locked position in which the first and third struts define the non-zero angle with each other, and the second and fourth struts define a second non-zero angle with each other and abutment portions of the second and fourth struts contact receiving portions of the third and first struts, respectively, and prevent the first and third struts from pivoting beyond the non-zero angle; and at least three third scissors, each third scissor comprising a fifth and a sixth strut, the fifth strut being pivotably connected to one of the hubs and the sixth strut being pivotably connected to the second and fourth struts. 20. The folding frame system as set forth in claim 19, wherein the third scissors are substantially perpendicular to the first and second scissors when the first, second, and third scissors are in an open position. 21. The folding frame system as set forth in claim 20, comprising a tension member associated with the first and the second scissor for retaining the first and the second scissor in the open, locked position. 22. The folding frame system as set forth in claim 21, wherein the tension member comprises a cover attached to the hubs. 23. The folding frame system as set forth in claim 19, comprising at least one foot member pivotably attached to the second end of at least one of the first, second, third, and fourth struts.