SUPPORTING FRAME FOLDABLE MULTIPLE TIMES

Abstract

A foldable supporting frame includes a first frame set, a second frame set, and a first link at each of the left and right sides of the foldable supporting frame to pivotally connect the first frame set with the second frame set. Each of the first and second frame sets includes a first frame unit, a second frame unit, and a second link at each of the left and right sides of the foldable supporting frame to pivotally connect the first frame unit with the second frame unit. The first link allows the first and second frame sets to fold and unfold with respect to each other, and the second link allows the first and second frame units to fold and unfold with respect to each other. As a result, the supporting frame can be folded at least three times and has a much smaller folded size.

Claims

1. A foldable supporting frame, comprising: a first frame set; a second frame set; and a first link at each of left and right sides of the foldable supporting frame to pivotally connect the first frame set with the second frame set, thereby allowing the first and second frame sets to fold and unfold with respect to each other, wherein each of the first and second frame sets comprises: a first frame unit; a second frame unit; and a second link at each of the left and right sides of the foldable supporting frame to pivotally connect the first frame unit with the second frame unit, thereby allowing the first and second frame units to fold and unfold with respect to each other.

2. The foldable supporting frame of claim 1, wherein the first and second frame sets are substantially the same and disposed symmetrically with respect to each other.

3. The foldable supporting frame of claim 1, wherein: the first frame unit comprises a first upper frame, a first lower frame, and a first plurality of supports, wherein the first upper frame comprises a first upper peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame; the first lower frame comprises a first lower peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame; and each support in the first plurality of supports is disposed between and pivotally connected to the first upper peripheral longitudinal bar of the first upper frame and the first lower peripheral longitudinal bar of the first lower frame; the second frame unit comprises a second upper frame, a second lower frame, and a second plurality of supports, wherein the second upper frame comprises a second upper peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame; the second lower frame comprises a second lower peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame; and each support in the second plurality of supports is disposed between and pivotally connected to the second upper peripheral longitudinal bar of the second upper frame and the second lower peripheral longitudinal bar of the second lower frame; the second link at each of the left and right sides of the foldable supporting frame comprises a second upper link and a second lower link, wherein the second upper link pivotally connects the first upper peripheral longitudinal bar of the first frame unit with the second upper peripheral longitudinal bar of the second upper frame at proximal end portions thereof; and the second lower link pivotally connects the first lower peripheral longitudinal bar of the first frame unit with the second lower peripheral longitudinal bar of the second upper frame at proximal end portions thereof; and the first link at each of the left and right sides of the foldable supporting frame comprises a first upper link and a first lower link, wherein the first upper link pivotally connects the second upper peripheral longitudinal bar of the second frame unit of the first frame set with the second upper peripheral longitudinal bar of the second frame unit of the second frame set; and the first lower link pivotally connects the second lower peripheral longitudinal bar of the second frame unit of the first frame set with the second lower peripheral longitudinal bar of the second frame unit of the second frame set.

4. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame, the first lower link comprises a bent upper portion, wherein when the foldable supporting frame is unfolded, the bent upper portion of the first lower link is disposed above the second upper peripheral longitudinal bar of the second frame unit of the first frame set and above the second upper peripheral longitudinal bar of the second frame unit of the second frame set, serving as a stopper to prevent the second lower frames of the second frame units of the first and second frame sets beyond their unfolded positions from further rotating beyond their unfolded positions.

5. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame, the first upper link comprises an upper portion and a lower portion, the upper portion of the first upper link pivotally connects the second upper peripheral longitudinal bars of the second frame units of the first and second frame sets, wherein the first link further comprises: a first middle link for each of the first and second frame sets, wherein the first middle link has a first end portion pivotally connected to the lower portion of the first upper link and a second end portion pivotally connected to a middle portion of an adjacent support of the second frame unit of the first or second frame set.

6. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets, the second upper link comprises a bent lower portion, wherein when the foldable supporting frame is unfolded, the bent lower portion of the second upper link is disposed below the first upper peripheral longitudinal bar of the first upper frame and the second upper peripheral longitudinal bar of the second upper frame, serving as a stopper to prevent the first and second upper frames beyond their unfolded positions from further rotating beyond their unfolded positions.

7. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets, the second lower link comprises an upper portion and a lower portion, the lower portion of the second lower link pivotally connects the first lower peripheral longitudinal bar of the first lower frame and the second lower peripheral longitudinal bar of the second lower frame, wherein the second link further comprises: a second middle link for each of the first and second frame units, wherein the second middle link has a first end portion pivotally connected to the upper portion of the second lower link and a second end portion pivotally connected to a middle portion of an adjacent support of the first or second frame unit.

8. The foldable supporting frame of claim 3, wherein: the second upper link of the second link and the first lower link of the first link are substantially the same, and disposed upside down with respect to each other; and the second lower link of the second link and the first upper link of the first link are substantially the same, and disposed upside down with respect to each other.

9. The foldable supporting frame of claim 3, wherein for each of the first and second frame sets: the first upper frame further comprises a first upper peripheral lateral bar integrally formed with the first upper peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame, wherein the first upper peripheral lateral bar and the first upper peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame collectively form a substantially U-shaped upper peripheral frame; and the first lower frame further comprises a first lower peripheral lateral bar integrally formed with the first lower peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame, wherein the first lower peripheral lateral bar and the first lower peripheral longitudinal bar at each of the left and right sides of the foldable supporting frame collectively form a substantially U-shaped lower peripheral frame.

10. The foldable supporting frame of claim 9, wherein for each of the first and second frame sets, the first U-shaped upper and lower peripheral frames are substantially the same as each other.

11. The foldable supporting frame of claim 9, wherein for each of the first and second frame sets, each of the first U-shaped upper and lower peripheral frames is made of a bent bar.

12. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets, the second upper and lower peripheral longitudinal bars are substantially the same as each other.

13. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets: the first lower peripheral longitudinal bar has a length different than that of the first upper peripheral longitudinal bar; and the second lower peripheral longitudinal bar has a length different than that of the second upper peripheral longitudinal bar.

14. The foldable supporting frame of claim 3, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets: the first lower peripheral longitudinal bar has a length shorter than that of the first upper peripheral longitudinal bar; and the second lower peripheral longitudinal bar has a length longer than that of the second upper peripheral longitudinal bar.

15. The foldable supporting frame of claim 14, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets, the second link further comprises: a connecting piece for each of the first and second upper frames, and fixedly coupled to the first upper peripheral longitudinal bar of the first frame unit or the second upper peripheral longitudinal bar of the second upper frame at the proximal end portion thereof, wherein the connecting piece is bent with a lug to pivotally connect the second upper link.

16. The foldable supporting frame of claim 15, wherein at each of the left and right sides of the foldable supporting frame and for each of the first and second frame sets, when the foldable supporting frame is folded, the second lower link is received in a space defined by the second upper link, the connecting piece fixedly coupled to the first upper peripheral longitudinal bar of the first upper frame unit, and the connecting piece fixedly coupled to the second upper peripheral longitudinal bar of the second upper frame unit.

17. The foldable supporting frame of claim 3, wherein a support in the first or second plurality of supports comprises a first segment and a second segment collectively forming a substantially L shape.

18. The foldable supporting frame of claim 17, wherein the support further comprises one or more third segments extended and bent from an edge of the first segment, wherein the second segment and the one or more third segments are located on the same side of the first segment, wherein the one or more third segments abut the first upper and lower peripheral longitudinal bars or abut the second upper and lower peripheral longitudinal bars when the foldable supporting frame is unfolded.

19. The foldable supporting frame of claim 3, wherein: the first upper frame further comprises one or more upper interior bars; the first lower frame further comprises one or more lower interior bars corresponding to the one or more upper interior bars; and the first frame unit further comprises one or more supports, each disposed between and pivotally connected to a respective upper interior bar in the one or more upper interior bars and a corresponding lower interior bar in the one or more lower interior bars.

20. The foldable supporting frame of claim 3, wherein: the second upper frame further comprises one or more upper interior bars; the second lower frame further comprises one or more lower interior bars corresponding to the one or more upper interior bars; and the second frame unit further comprises one or more supports, each disposed between and pivotally connected to a respective upper interior bar in the one or more upper interior bars and a corresponding lower interior bar in the one or more lower interior bars.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate one or more embodiments of the present application and, together with the detailed description, serve to explain the principles and implementations of the application.

[0025] FIG. 1 is a schematic perspective view illustrating an exemplary foldable supporting frame in an unfolded state in accordance with some embodiments of the present invention.

[0026] FIG. 2 is a partially exploded view illustrating the exemplary foldable supporting frame of FIG. 1.

[0027] FIG. 3 is a schematic perspective view illustrating an exemplary support in accordance with some embodiments of the present invention.

[0028] FIG. 4 is an enlarged view taken along circle A of FIG. 1.

[0029] FIG. 5 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a first partially folded state.

[0030] FIG. 6 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a second partially folded state.

[0031] FIG. 7 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a third partially folded state.

[0032] FIG. 8 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a fourth partially folded state.

[0033] FIG. 9 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a fifth partially folded state.

[0034] FIG. 10 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a sixth partially folded state.

[0035] FIG. 11 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 1 in a folded state.

[0036] FIG. 12 is an enlarged view taken along circle B of FIG. 11.

[0037] FIG. 13 is a schematic perspective view illustrating another exemplary foldable supporting frame in an unfolded state in accordance with some embodiments of the present invention.

[0038] FIG. 14 is a partially exploded view illustrating the exemplary foldable supporting frame of FIG. 13.

[0039] FIG. 15 is an enlarged view taken along circle C of FIG. 13.

[0040] FIG. 16 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 13 in a first partially folded state.

[0041] FIG. 17 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 13 in a second partially folded state.

[0042] FIG. 18 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 13 in a third partially folded state.

[0043] FIG. 19 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 13 in a fourth partially folded state.

[0044] FIG. 20 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 13 in a fifth partially folded state.

[0045] FIG. 21 is a schematic perspective view illustrating the exemplary foldable supporting frame of FIG. 13 in a folded state.

[0046] FIG. 22 is an enlarged view taken along circle D of FIG. 21.

[0047] FIG. 23 is an enlarged view taken along circle E of FIG. 13.

[0048] FIG. 24 is an enlarged view taken along circle F of FIG. 21.

DETAILED DESCRIPTION

[0049] Reference will now be made in detail to implementations of the present application as illustrated in the accompanying drawings. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts. Those of ordinary skill in the art will realize that the following detailed description of the present application is illustrative only and is not intended to be in any way limiting. Other embodiments of the present application will readily suggest themselves to such skilled persons having benefit of this disclosure.

[0050] In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions are made in order to achieve the developer's specific goals, such as compliance with application- and business-related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure.

[0051] Many modifications and variations of the exemplary embodiments set forth in this disclosure can be made without departing from the spirit and scope of the embodiments, as will be apparent to those skilled in the art. The specific exemplary embodiments described herein are offered by way of example only, and the disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled.

[0052] Embodiments of the present invention are described in the context of supporting frames. The supporting frames can be of various sizes including but not limited to twin, full, queen and king sizes, and of various shapes including but not limited to rectangles and squares. Also, the supporting frames can be made of various materials including but not limited to plastics, woods, and metals such as iron and steel. The supporting frames can be used alone or in conjunction with bed frames. For example, the supporting frames can be placed on bed frames, before placing support mattresses, cushions, box springs or the like on the supporting frames, to increase the heights of the beds to accommodate users' different heights or preferences.

[0053] Generally, a supporting frame of the present invention includes first and second frames sets pivotally coupled to each other such that the first and second frame sets can be folded and unfolded with respect to each other. Each of the first and second frame sets includes first and second frame units pivotally connected to each other such that the first and second frame units can be folded and unfolded with respect to each other. As such, the supporting frame of the present invention can be folded at least three times, resulting in a much smaller folded size comparing to conventional supporting frames. Accordingly, the supporting frames are easier and convenient to handle, carry, store and transport.

[0054] Referring now to FIGS. 1, 2 and 4, there is depicted exemplary supporting frame 1a in accordance with some exemplary embodiments of the present invention. As shown, exemplary supporting frame 1a includes two frame sets such as first and second frame sets 10. The two frame sets can be the same as or different from each other. In some exemplary embodiments such as those illustrated in the figures, the first and second frame sets are substantially the same and disposed symmetrically with respect to each other.

[0055] The first and second frame sets are pivotally connected to each other at their proximal end portions by a first link such as first link 20 at each of the left and right sides (e.g., the two longitudinal sides) of the foldable supporting frame. First link 20 allows the first and second frame sets to fold and unfold with respect to each other. Each of the first and second frame sets includes a first frame unit such as first frame unit 100 and a second frame unit such as second frame unit 110. First frame unit 100 and second frame unit 110 are pivotally connected to each other at their proximal end portions by a second link such as second link 30 at each of the left and right sides of the foldable supporting frame. Second link 30 allows the first and second frame units to fold and unfold with respect to each other. As such, the foldable supporting frame of the present invention can be folded at least three times, resulting in a much smaller folded size comparing to conventional foldable supporting frames. Accordingly, the foldable supporting frame of the present invention is easier and convenient to handle, carry, store, and transport.

[0056] As used herein, the term proximal refers to a relative position or a relative segment. For instance, the proximal end portion of the first frame set is relative to the second frame set, and vice versa. In FIG. 1, the proximal end portions of the first and second frame sets are in the middle portion of the figure. The proximal end portion of first frame unit 100 is relative to second frame unit 110, and vice versa. In FIG. 1, the proximal end portions of the first and second frame units are in the middle portion of each respective frame set 10.

[0057] In some exemplary embodiments, first frame unit 100 includes a first upper frame such as first upper frame 102, a first lower frame such as first lower frame 104, and a first plurality of supports such as support 40. Upper frame 102 can be the same as or different from lower frame 104. At each of the left and right sides of the foldable supporting frame, first upper frame 102 includes first upper peripheral longitudinal bar 105, and first lower frame 104 includes first lower peripheral longitudinal bar 106. Each support in the first plurality of supports is disposed between and pivotally connected to the first upper peripheral longitudinal bar of the first upper frame and the first lower peripheral longitudinal bar of the first lower frame.

[0058] Similarly, in some exemplary embodiments, second frame unit 110 includes a second upper frame such as second upper frame 112, a second lower frame such as second lower frame 114, and a second plurality of supports such as support 40. Upper frame 112 can be the same as or different from lower frame 114. At each of the left and right sides of the foldable supporting frame, second upper frame 112 includes second upper peripheral longitudinal bar 115, and second lower frame 114 includes second lower peripheral longitudinal bar 116. Each support in the second plurality of supports is disposed between and pivotally connected to the second upper peripheral longitudinal bar of the second upper frame and the second lower peripheral longitudinal bar of the second lower frame. In an exemplary embodiment, the second upper peripheral longitudinal bar of the second upper frame and the second lower peripheral longitudinal bar of the second lower frame are substantially the same as each other. For instance, the second upper peripheral longitudinal bar of the second upper frame and the second lower peripheral longitudinal bar of the second lower frame have substantially the same length.

[0059] First link 20 includes a first upper link such as first upper link 202 and a first lower link such as first lower link 204. The first upper link pivotally connects the second upper peripheral longitudinal bar of the second frame unit of the first frame set with the second upper peripheral longitudinal bar of the second frame unit of the second frame set. The first lower link pivotally connects the second lower peripheral longitudinal bar of the second frame unit of the first frame set with the second lower peripheral longitudinal bar of the second frame unit of the second frame set. In some exemplary embodiments, when the supporting frame is unfolded, the pivotal points at which first upper link 202 pivotally connects the second upper peripheral longitudinal bars of the first and second frame sets are not aligned with the pivotal points at which first lower link 204 pivotally connects the second lower peripheral longitudinal bars of the first and second frame sets as illustrated by dash lines a and b in FIG. 4.

[0060] In an exemplary embodiment, first lower link 204 includes a bent upper portion such as bent upper portion 206. When the foldable supporting frame is unfolded, bent upper portion 206 is disposed above the second upper peripheral longitudinal bar of the second frame unit of the first frame set and above the second upper peripheral longitudinal bar of the second frame unit of the second frame set. At such a position, bent upper portion 206 serves as a stopper to prevent the second lower frames of the second frame units of the first and second frame sets from further rotating beyond their unfolded positions.

[0061] In some exemplary embodiments, first upper link 202 includes an upper portion and a lower portion as illustrated in FIG. 4. The upper portion of the first upper link pivotally connects the second upper peripheral longitudinal bars of the second frame units of the first and second frame sets. In an exemplary embodiment, first link 20 further includes a first middle link such as first middle link 208 for each of the first and second frame sets. The first middle link has a first end portion pivotally connected to the lower portion of first upper link 202 and a second end portion pivotally connected to a middle portion of an adjacent support 40 of the second frame unit of the first or second frame set.

[0062] In some exemplary embodiments, for each of the first and second frame sets, second link 30 includes a second upper link such as second upper link 300 and a second lower link such as second lower link 302. The second upper link pivotally connects the first upper peripheral longitudinal bar of the first frame unit with the second upper peripheral longitudinal bar of the second upper frame at their proximal end portions. The second lower link pivotally connects the first lower peripheral longitudinal bar of the first frame unit with the second lower peripheral longitudinal bar of the second upper frame at their proximal end portions.

[0063] In some exemplary embodiments, for each of the first and second frame sets, second upper link 300 includes a bent lower portion such as bent lower portion 306. When the foldable supporting frame is unfolded, bent lower portion 306 is disposed below the first upper peripheral longitudinal bar of the first upper frame and the second upper peripheral longitudinal bar of the second upper frame. At such a position, bent lower portion 306 of second link 30 serves as a stopper to prevent the first and second upper frames from further rotating beyond their unfolded positions. In an exemplary embodiment, second upper link 300 of second link 30 is substantially the same as first lower link 204 of first link 20, but disposed upside down.

[0064] In some exemplary embodiments, for each of the first and second frame sets, second lower link 302 includes an upper portion and a lower portion. The lower portion of the second lower link pivotally connects the first lower peripheral longitudinal bar of the first lower frame and the second lower peripheral longitudinal bar of the second lower frame. In an exemplary embodiment, second link 30 further includes a second middle link such as second middle link 304 for each of the first and second frame units. Second middle link 304 has a first end portion pivotally connected to the upper portion of second lower link 302 and a second end portion pivotally connected to a middle portion of an adjacent support 40 of the first or second frame unit. In an exemplary embodiment, second lower link 302 of second link 30 is substantially the same as first upper link 202 of first link 20, but disposed upside down.

[0065] In some exemplary embodiments, for each of the first and second frame sets, first upper frame 102 further includes first upper peripheral lateral bar 107, and first lower frame 104 further includes first lower peripheral lateral bar 108. First upper peripheral lateral bar 107 is integrally formed, for instance by bending a bar, with first upper peripheral longitudinal bar 105 at each of the left and right sides of the foldable supporting frame. In an exemplary embodiment, first upper peripheral lateral bar 107 and first upper peripheral longitudinal bar 105 at each of the left and right sides of the foldable supporting frame collectively form a substantially U-shaped upper peripheral frame. Similarly, first lower peripheral lateral bar 108 is integrally formed, for instance by bending a bar, with first lower peripheral longitudinal bar 106 at each of the left and right sides of the foldable supporting frame. In an exemplary embodiment, first lower peripheral lateral bar 108 and first lower peripheral longitudinal bar 106 at each of the left and right sides of the foldable supporting frame collectively form a substantially U-shaped lower peripheral frame. In an exemplary embodiment, for each of the first and second frame sets, the first U-shaped upper and lower peripheral frames are substantially the same as each other.

[0066] Referring to FIGS. 3 and 4, there is depicted an exemplary support in accordance with some embodiments of the present invention. As shown, support 40 has a first segment such as first segment 42 and a second segment such as second segment 44. In an exemplary embodiment, first segment 42 and second segment 44 collectively form a substantially L shape. In some exemplary embodiments, support 40 further includes one or more third segments such as third segment 46. By way of illustration, FIGS. 3 and 4 show two third segments 46. Third segment 46 can have any suitable length. In an exemplary embodiment, third segment 46 is extended and bent from an edge of first segment 42, and is located on the same side as of second segment 44. The support can be disposed in various directions as long as one of the first and second segments is connected to the upper frame and the other of the first and second segments is connected to the lower frame. When the foldable supporting frame is unfolded, the one or more third segments abut the upper and lower frames to help supporting the upper frames.

[0067] Referring to FIGS. 5-11, there is depicted an exemplary process to fold the supporting frame. First, rotate first frame unit 100 of the first frame set in a first direction for approximately 90 degrees as illustrated in FIG. 5. During the rotation, the first upper and lower frames of the first frame unit move toward each other and, in some cases, touch each other at the end of the rotation. Then, rotate second frame unit 110 of the first frame set along with the first frame unit in a second direction for approximately 90 degrees as illustrated in FIG. 6. During the rotation, the second upper and lower frames of the second frame unit move toward each other and, in some cases, touch each other at the end of the rotation. Then, fold the first frame unit of the first frame set onto the second frame unit of the first frame set as illustrated in FIG. 7. Afterwards, rotate second frame unit 110 of the second frame set towards the folded first frame set 10 as illustrated in FIG. 8 until it is folded onto the first frame set 10 as illustrated in FIG. 9. Then, rotate first frame unit 100 of the second frame set towards the folded first frame set 10 and second frame unit 110 of the second frame set as illustrated in FIG. 10. The folded supporting frame is illustrated in FIG. 11.

[0068] In some exemplary embodiments, the first and second frame units are substantially the same and arranged symmetrically. In such exemplary embodiments, when the supporting frame is folded, the pivotal points at which second upper links 300 pivotally connect the first and second upper peripheral longitudinal bars of the first and second frame sets are aligned with each other as illustrated by dash line e in FIG. 12. In an exemplary embodiment, when the supporting frame is folded, the pivotal points at which the adjacent supports pivotally connect the first and second upper peripheral longitudinal bars of the first and second frame sets are also aligned with each other as illustrated by dash line f in FIG. 12.

[0069] The foldable supporting frames of the present invention can include additional, optional, modified, or alternative components. For instance, referring to FIGS. 13-15, there is depicted exemplary supporting frame 1b in accordance with some exemplary embodiments of the present invention. Like exemplary supporting frame 1a, exemplary supporting frame 1b includes first and second frame sets 10 pivotally connected to each other by first link 20 at each of the left and right sides of the foldable supporting frame. Each of the first and second frame sets includes first frame unit 100, second frame unit 110, and second link 30 at each of the left and right sides of the foldable supporting frame pivotally connecting first frame unit 100 with second frame unit 110. In some exemplary embodiments, first frame unit 100 includes upper frame 102 and lower frame 104, and second frame unit 110 includes upper frame 112 and lower frame 114.

[0070] Unlike exemplary supporting frame 1a, in some exemplary embodiments, first lower peripheral longitudinal bar 106 of exemplary supporting frame 1b has a length different than that of first upper peripheral longitudinal bar 105, and second lower peripheral longitudinal bar 116 has a length different than that of second upper peripheral longitudinal bar 115. In an exemplary embodiment, first lower peripheral longitudinal bar 106 of exemplary supporting frame 1b has a length shorter than that of first upper peripheral longitudinal bar 105, and second lower peripheral longitudinal bar 116 has a length longer than that of second upper peripheral longitudinal bar 115. Conversely, in an exemplary embodiment, first lower peripheral longitudinal bar 106 of exemplary supporting frame 1b has a length longer than that of first upper peripheral longitudinal bar 105, and second lower peripheral longitudinal bar 116 has a length shorter than that of second upper peripheral longitudinal bar 115.

[0071] In such exemplary embodiments, when the supporting frame is unfolded, the pivotal points at which second lower links 302 pivotally connect the first and second lower peripheral longitudinal bars are not aligned with the pivotal points at which second upper links 300 pivotally connect the first and second upper peripheral longitudinal bars as illustrated by dash lines c and d in FIG. 23. In some exemplary embodiments, the upper and lower frames are configured such that when the supporting frame is folded, the pivotal points at which second lower links 302 pivotally connect the first and second lower peripheral longitudinal bars are aligned with the pivotal points at which second upper links 300 pivotally connect the first and second upper peripheral longitudinal bars as illustrated in FIGS. 21 and 24.

[0072] Referring to FIGS. 15, 21 and 22, in some exemplary embodiments, for each of the first and second frame sets, second link 30 further includes a connecting piece such as connecting piece 308 for each of the first and second upper frames. Connecting piece 308 is fixedly coupled to a proximal end portion of the first upper peripheral longitudinal bar of first frame unit 102 or a proximal end portion of the second upper peripheral longitudinal bar of second upper frame 112. The connecting piece is bent with a lug such as lug 310 to pivotally connect second upper link 300. With respect to the first or second upper peripheral longitudinal bar, the connecting piece is bent inwardly such that when the supporting frame is folded, second upper link 300 and connecting pieces 308 fixedly coupled to the first and second upper peripheral longitudinal bars collectively define a space to receive second lower link 302.

[0073] Referring to FIGS. 16-21, there is depicted an exemplary process to fold the supporting frame. First, rotate first and second frame sets toward each other as illustrated in FIG. 16, until they are folded onto each other as illustrated in FIG. 17. Then, rotate the first frame unit of one frame set as illustrated in FIG. 18, until it is folded onto the second frame unit of the one frame set as illustrated in FIG. 19. Afterwards, rotate the first frame unit of the other frame set as illustrated in FIG. 20. The folded supporting frame is illustrated in FIG. 21.

[0074] Referring to FIGS. 1 and 13, in some exemplary embodiments, first or second frame unit includes additional components such as interior bars. Interior bars can be disposed either longitudinally or laterally. For instance, in some exemplary embodiments, first upper frame 102 further includes one or more upper interior bars such as longitudinal bar 501. Corresponding to the one or more upper interior bars, first lower frame 104 further includes one or more lower interior bars such as longitudinal bar 502. In an exemplary embodiment, first frame unit further includes one or more supports such as support 40, each disposed between and pivotally connected to a respective upper interior bar in the one or more upper interior bars and a corresponding lower interior bar in the one or more lower interior bars.

[0075] Similarly, in some exemplary embodiments, second upper frame 112 further includes one or more upper interior bars such as longitudinal bar 503. Corresponding to the one or more upper interior bars, second lower frame 114 further includes one or more lower interior bars such as longitudinal bar 504. In an exemplary embodiment, second frame unit 110 further includes one or more supports such as support 40, each disposed between and pivotally connected to a respective upper interior bar in the one or more upper interior bars and a corresponding lower interior bar in the one or more lower interior bars.

[0076] As disclosed herein, the supporting frames of the present invention can be folded at least three times, resulting in a much smaller folded size. As such, it is easy and convenient to carry, store and transport the supporting frames of the present invention.

[0077] The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the claims. As used in the description of the implementations and the appended claims, the singular forms a, an and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be understood that the terms upper or lower, left or right, lateral or longitudinal and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures. It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first link could be termed a second link, and, similarly, a second link could be termed a first link, without changing the meaning of the description, so long as all occurrences of the first link are renamed consistently and all occurrences of the second link are renamed consistently.