TECHNICAL FIELD

[0001] The present disclosure relates to fastening of tubes. In particular, the present disclosure relates to a mechanism and technique for fastening of tubes/rods that form part of a frame, making the frame foldable.

BACKGROUND

[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0003] Microlight / Ultralight aircrafts and gliders are category of airplanes that are affordable and can be purchased without hassle. However, in order to operate these aircrafts, they need to be transported to an airfield and / or require to be parked at the airfield. Transportation and parking have their inherent difficulties that are neither easy nor cost effective.

[0004] Flex wing aircrafts such as Hang Gliders, powered Hang Gliders, Paragliders, and powered Paragliders are cost effective to transport and operate. However, this category of airplanes has low aerodynamic performance, and therefore there is a need to create an aircraft with foldable wings, foldable tail plane, and foldable structure that occupies less space for storage, is easy to transport, and is quick to assemble for flight. In existing architectures, structure of wings does not collapse or fold, rather the mounting location is changed and is termed as folded wing as seen in existing Kolb Aircraft.

[0005] Therefore, in existing architectures, structure of the wing collapses only in a manner that results in small form factor for transport or storage, and therefore there is a need in the art for an improved mechanism and technique for making wings / frame foldable.

[0006] In some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0007] As used in the description herein and throughout the claims that follow, the meaning of“a,”“an,” and“the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of“in” includes“in” and “on” unless the context clearly dictates otherwise.

[0008] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g.“such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0009] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

OBJECTS OF THE INVENTION

[0010] Another object of the present disclosure is to provide a mechanism and technique for fastening of tubes / rods that forms part of an aircraft frame.

[0011] Another object of the present disclosure is to provide a foldable aircraft frame.

[0012] Another object of the present disclosure is to provide an aircraft frame that is easily collapsible.

[0013] Another object of the present disclosure is to provide an aircraft frame that enables quick assembly of the tubes. [0014] Another object of the present disclosure is to provide an aircraft frame that is easy to transport from one place to another.

[0015] Yet another object of the present disclosure is to provide an aircraft frame that is lightweight and occupies less space.

[0016] Still another object of the present disclosure is to provide an aircraft frame that can be retrofitted to existing microlight as well as flex wing aircrafts without any major design alterations.

SUMMARY

[0017] The present disclosure relates to fastening of tubes / rods. In particular, the present disclosure relates to a mechanism and technique for fastening of tubes that form part of an aircraft frame, making the frame foldable.

[0018] In an aspect, the present disclosure relates to an aircraft comprising a frame that includes a plurality of tubes, said plurality of tubes including at least a first tube and a second tube that are fastened with each other using at least one fork plate, said at least one fork plate having a first end and a second end, wherein said at least one fork plate is, at its first end, pivotally fixed to the first tube, and wherein the at least one fork plate is adapted to pivotally engage the second tube at a point that is intermediate between the first end and the second end; and wherein the fork plate further comprises a fork plate hole at its second end that is used for engaging a fastening member when the fork plate hole is in alignment with a second tube hole that is configured in the second tube so as to hold the second tube in an extended position.

[0019] In an aspect, the engagement of the second tube with the at least one fork plate is through an open slot at end of the second tube, wherein the open slot removably engages with a fixed pin located on the at least one fork plate at the intermediate point.

[0020] In an aspect, the fixed pin is fixed perpendicular to the at least one fork plate, and incorporates at its free end a means to prevent lateral movement of the second tube.

[0021] In an aspect, the first tube and the second tube are joined using two fork plates, each configured on diametrically opposite positions of the tubes.

[0022] In an aspect, the fixed pin is configured between two fork plates.

[0023] In an aspect, the frame is configured with a set of drag braces to retain stiffness.

[0024] In an aspect, the present disclosure provides a fork plate configured to join a first tube with a second tube, said fork plate having a first end and a second end, wherein the fork plate is, at its first end, pivotally fixed to the first tube, and wherein the fork plate pivotally engages to the second tube at a point intermediate between the first end and the second end through a fixed pin fixed on the fork plate and an open slot at end of the second tube, and wherein the fork plate further comprises a fork plate hole at its second end that is used for engaging a fastening member when the fork plate hole is in alignment with a second tube hole that is configured in the second tube so as to hold the second tube in an extended position.

[0025] In an aspect, the fastening member is a bolt or a pin.

[0026] In an aspect, removal of the fastening member enables bringing the second tube to a collapsed position, and wherein the open slot at the end of the second tube enables disengagement of the second tube from the fork plate.

[0027] In an aspect, the present disclosure provides a tube that includes an open slot at one end of the tube and a hole spaced apart longitudinally from the open slot, said open slot being configured to pivotally engage with a fixed pin of a fork plate, the fixed pin being fixed at an intermediate point of the fork plate such that a fork plate hole configured at a first end of the fork plate engages with the hole of the tube through a fastening member and enables the tube to take an extended position when a second end of the fork plate is pivotally coupled with a second tube.

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0029] The diagrams are for illustration only, which thus is not a limitation of the present disclosure, and wherein:

[0030] FIGs. 1 A through 1D illustrate exemplary representation showing fastening of two tubes using proposed mechanism in accordance with an embodiment of the present disclosure.

[0031] FIG. 2 illustrates an exemplary photographic representation of proposed tube to tube joint using a quick release pin in accordance with aspects of the present disclosure.

[0032] FIG. 3 illustrates an exemplary photographic representation of the second tube/member having a hole for engaging with a fastening member when in alignment with fork plate hole where the second tube is pivotally connected with the fork plate at its one end in accordance with aspects of the present disclosure.

[0033] FIGs. 4A and 4B illustrate exemplary photographic representations of the proposed wing frame in extended and collapsed state respectively.

DETAILED DESCRIPTION

[0034] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

[0035] Various terms as used herein are explained below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.

[0036] The present disclosure relates to fastening of tubes / rods. In particular, the present disclosure relates to a mechanism and technique for fastening of tubes / rods that form part an aircraft frame, making the wing frame foldable.

[0037] In an aspect, the present disclosure relates to an aircraft comprising a frame

(also referred to as“wing frame” hereinafter) that includes a plurality of tubes / rods, said plurality of tubes including at least a first tube and a second tube that are fastened with each other using at least one fork plate, said at least one fork plate having a first end and a second end, wherein said at least one fork plate is, at its first end, pivotally fixed to the first tube, and wherein the at least one fork plate is adapted to pivotally engage the second tube at a point that is intermediate between the first end and the second end; and wherein the fork plate further comprises a fork plate hole at its second end that is used for engaging a fastening member when the fork plate hole is in alignment with a second tube hole that is configured in the second tube so as to hold the second tube in an extended position.

[0038] In an aspect, the engagement of the second tube with the at least one fork plate is through an open slot at end of the second tube, wherein the open slot removably engages with a fixed pin located on the at least one fork plate at the intermediate point.

[0039] In an aspect, the fixed pin is fixed perpendicular to the at least one fork plate, and incorporates at its free end a means to prevent lateral movement of the second tube. [0040] In an aspect, the first tube and the second tube are joined using two fork plates, each configured on diametrically opposite positions of the tubes.

[0041] In an aspect, the fixed pin is configured between two fork plates.

[0042] In an aspect, the wing frame is configured with a set of drag braces to retain stiffness of the wing frame.

[0043] In an aspect, the present disclosure provides a fork plate configured to join a first tube with a second tube, said fork plate having a first end and a second end, wherein the fork plate is, at its first end, pivotally fixed to the first tube, and wherein the fork plate pivotally engages to the second tube at a point intermediate between the first end and the second end through a fixed pin fixed on the fork plate and an open slot at end of the second tube, and wherein the fork plate further comprises a fork plate hole at its second end that is used for engaging a fastening member when the fork plate hole is in alignment with a second tube hole that is configured in the second tube so as to hold the second tube in an extended position.

[0044] In an aspect, the fastening member is a bolt or a pin.

[0045] In an aspect, removal of the fastening member enables bringing the second tube to a collapsed position, and wherein the open slot at the end of the second tube enables disengagement of the second tube from the fork plate.

[0046] In an aspect, the present disclosure provides a tube / rod that includes an open slot at one end of the tube and a hole spaced apart longitudinally from the open slot, said open slot being configured to pivotally engage with a fixed pin of a fork plate, the fixed pin being fixed at an intermediate point of the fork plate such that a fork plate hole configured at a first end of the fork plate engages with the hole of the tube through a fastening member and enables the tube to take an extended position when a second end of the fork plate is pivotally coupled with a second tube.

[0047] FIGs. 1A through 1D illustrate exemplary representations showing how two tubes can be fastened together using aspects of the present invention. In an aspect, the proposed construction can include a fork plate 300 that is configured to join a first tube 100 with a second tube 200, said fork plate 300 having a first end 302 and a second end 304, wherein the fork plate 300 is, at its first end 302, pivotally fixed to the first tube 100, and wherein the fork plate 300 is adapted to pivotally engage the second tube 200 at a point 306 intermediate between the first end 302 and the second end 304, and wherein the fork plate 300 further comprises a fork plate hole 308 at its second end 304 that is used for engaging a fastening member when the fork plate hole 308 is in alignment with a second tube hole 202 that is configured in the second tube 200 so as to hold the second tube 200 in an extended position.

[0048] In an aspect of the present disclosure as illustrated in FIG. 1 A, the second tube

200 can include a second tube hole 202 and an open slot 204 at one end of the second tube 200 that can engage to the fork plate 300 at the point 306 intermediate between the first end 302 and the second end 304 of the fork plate 300.

[0049] In an aspect, engagement of the second tube 200 with the fork plate 300 through the open slot 204 at the end of the second tube 200, wherein the open slot 204 can removably engage with a fixed pin (not shown) located on the fork plate 300 at the intermediate point 306. In an aspect, the fixed pin can be fixed perpendicular to the fork plate 300 and can incorporate at its free end a means to prevent lateral movement of the second tube 200. In an aspect, the means to prevent lateral movement of the second tube 200 can include any or a combination of a flange, a dowel pin and a slotted fork plate to restrict lateral movement of the second tube 200.

[0050] In an aspect, one end of the fixed pin can be configured with the fork plate 300 at the point 306 intermediate between the first end 302 and the second end 304 of the fork plate 300, and other end can be supported by a flange to prevent lateral movement of the second tube 200 along the pin. In an aspect, the flange can restrict lateral movement of the open slot 204 of the second tube 200.

[0051] In an aspect, the first tube 100 and the second tube 200 can be joined using two fork plates (such as 300-1 and 300-2), each configured on diametrically opposite positions of the tubes 100/200.

[0052] In an aspect, a fixed pin can be configured between two fork plates 300-1 and

300-2 to prevent lateral movement of the second tube 200. Lateral movement of the second tube 200 is prevented by the presence of the two fork plates 300-1 and 300-2 at each lateral side of the slot 204.

[0053] In an aspect, removal of the fastening member enables bringing the second tube 200 to a collapsed position, and wherein the open slot 204 at the end of the second tube 200 can enable disengagement of the second tube 200 from the fork plate 300.

[0054] In an aspect, the present disclosure relates to an aircraft comprising a frame that includes a plurality of tubes / rods, where the plurality of tubes can include a first tube 100 and a second tube 200 that are fastened with each other using at least one fork plate 300. In an aspect, the at least one fork plate 300 can have a first end 302 and a second end 304, where the at least one fork plate 300 is, at its first end 302, pivotally fixed to the first tube 100, and where the at least one fork plate 300 can pivotally engage to the second tube 200 at a point 306 that is intermediate between the first end 302 and the second end 304 through an open slot 204 in the second tube 200. Furthermore, the fork plate 300 can further include a fork plate hole 308 at its second end that is used for engaging a fastening member when the fork plate hole 308 is in alignment with a second tube hole 202 that is configured in the second tube 200 so as to hold the second tube 200 in an extended position.

[0055] In an aspect, the fastening member can be any or a combination of a bolt or a pin such that removal of the fastening member enables bringing the second tube 200 to a collapsed position. In an aspect, the open slot 204 at end of the second tube 200 can enable disengagement of the second tube 200 from the fork plate 300.

[0056] In an aspect, by implementing the proposed fastening technique to connect two tubes of an aircraft frame, a tube to tube joint can be easily realized utilizing just a quick connecting pin or one or more bolts as the fastening member. In an aspect, drag braces / cables can be used to retain stiffness of the frame.

[0057] In an aspect, the present disclosure further relates to a fork plate that is configured to join a first tube with a second tube, said fork plate having a first end and a second end, wherein the fork plate is, at its first end, pivotally fixed to the first tube, and wherein the fork plate pivotally engages to the second tube at a point intermediate between the first end and the second end through a fixed pin fixed on the fork plate and an open slot at end of the second tube, and wherein the fork plate further comprises a fork plate hole at its second end that is used for engaging a fastening member when the fork plate hole is in alignment with a second tube hole that is configured in the second tube so as to hold the second tube in an extended position.

[0058] The present disclosure further relates to a tube / rod that includes an open slot at one end of the tube and a hole spaced apart longitudinally from the open slot, said open slot being configured to pivotally engage with a fixed pin of a fork plate, the fixed pin being fixed at an intermediate point of the fork plate such that a fork plate hole configured at a first end of the fork plate engages with the hole of the tube through a fastening member and enables the tube to take an extended position when a second end of the fork plate is pivotally coupled with a second tube.

[0059] In an aspect, the proposed mechanism / technique for fastening of tubes using the fork plate can be implemented and / or retrofitted in existing microlight as well as flex wing aircrafts and gliders without any major design and structural alteration. [0060] In an aspect, the proposed aircraft can include one or more foldable wings that utilize the proposed technique / mechanism of fastening tubes which enables the wings/structures to be collapsible and foldable like that of a hang glider. The proposed folded wings are easy to carry and can be assembled back with ease in a short time interval.

[0061] In an aspect, the present invention relates particularly to microlight/ultralight aircrafts and gliders, wherein in an embodiment, the present disclosure relates to aircrafts or structures that can be easily folded for transportation and storage and thereafter can be assembled back for flight or usage. The proposed technique of using foldable / extendable tubes / rods is applicable to tube fastening, and can be utilized on existing aircrafts or structures so as to enhance their portability. The proposed fastening mechanism has wide application from manned to unmanned aerial vehicles and different structures of the aerial vehicles.

[0062] In an aspect, the present disclosure further provides for a new category of aircrafts / gliders that are portable, affordable, and high-performance. A foldable wing structure incorporating the proposed tube fastening mechanism is structurally strong and quick to assemble, wherein the structure is compact to store and easy to transport after folding. The design retains its structural rigidity and has higher aerodynamic performance as compared to foldable flex wing aircrafts that are weight shift control and not 3 or 2 axis control.

[0063] In an aspect, the proposed ultralight/microlight aircrafts and gliders can use aluminum tube construction, wherein the tubes carry both compressive and tensile loads. Cable rigging can also be used when structural members/tubes are in tension which utilizes tumbuckles for adjustment. Tubes in tension can be replaced by cable bracing as per the design requirements.

[0064] In an aspect, the present disclosure provides a compact, portable and affordable solution to lightweight aircrafts by providing a novel fastening technique to fasten a plurality of tubes that form part of wing frame of an aircraft. Furthermore, the proposed fastening technique provides for length adjustment of a structural tube/member connected to a second structural member which results in adjustment of force in the structural member thereby utilizing mechanical advantage of the fork assembly.

[0065] FIG. 2 illustrates an exemplary photographic representation of proposed tube to tube joint using a quick release pin in accordance with aspects of the present disclosure. As would be appreciated, tube to tube joint as proposed can be easily realized here utilizing just a quick connecting pin or one bolt, wherein use of one bolt can be made possible by slotting one hole next to the tube edge.

[0066] FIG. 3 illustrates an exemplary photographic representation of the second tube

/ member 200 having a hole 202 for engaging with a fastening member when in alignment with fork plate hole 308, wherein the second tube 200 is pivotally connected with the fork plate 300 at its one end configured with the slot 204 through a fixed pin located on the fork plate 300 at the intermediate point 306.

[0067] As would be appreciated, slotting the hole in the proposed structure does not result in strength reduction since the material removed does not contribute to load bearing area in compression. Furthermore, a suitable truss design consisting of cables and rigid member can be realized by incorporating the proposed feature that negates use of turnbuckles (used for cable tensioning). Even further, statically determinate / indeterminate truss designed using this feature is easy to assemble and dis-assemble.

[0068] FIGs. 4A and 4B illustrate exemplary photographic representations of the proposed wing frame in extended and collapsed state respectively, wherein, in order to dis- assemble, three quick connect pins can be used to collapse the tubes that connect with each other using the proposed technique.

[0069] In an aspect, the first tube 100 and the second tube 200 can be connected using two fork plates 300-1 and 300-2 such that when the wing assembly / frame is in the extended state, fork plate holes 308 of the fork plates 300-1 and 300-2 are used for engaging a fastening member such as a bolt or a pin when the fork plate hole 308 is in alignment with a second tube hole 202 that is configured in the second tube 200 so as to hold the second tube 200 in an extended position. In an aspect, drag braces 402 (as shown in FIG. 4A) can be used to retain stiffness of the wing assembly. Mechanical advantage of the fork assembly can be utilized to preload members/tubes/rods in the frame.

[0070] In an aspect of the present disclosure as shown in FIG. 4B, the fastening member configured with the fork plate holes 308 of the fork plate 300-1 and 300-2 can be removed to bring the second tube 200 to a collapsed position, where the open slot 204 at the end of the second tube 200 can enable disengagement of the second tube 200 from the fork plates 300-1 and 300-2. Microlight aircraft wings can usually be supported at 2 or 3 points (fuselage root support + either 1 or 2 struts), wherein as can be seen, the representations of FIGs. 4A and 4B attach a wing on 2 supports.

[0071] It would be appreciated that although the proposed disclosure is explained in terms of application of the proposed fastening mechanism to a single surface wing of an aircraft, the scope of the present disclosure is not limited to the same in any way, and application of the proposed fastening mechanism to double surface symmetrical wings or tube structures is well within the scope of the present disclosure.

[0072] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION

[0073] The present disclosure provides a mechanism and technique for fastening of tubes / rods that forms part of an aircraft frame.

[0074] The present disclosure provides a foldable aircraft frame.

[0075] The present disclosure provides an aircraft frame that is easily collapsible.

[0076] The present disclosure provides an aircraft frame that enables quick assembly of the tubes.

[0077] The present disclosure provides an aircraft frame that is easy to transport from one place to another.

[0078] The present disclosure provides an aircraft frame that is lightweight and occupies less space.

[0079] The present disclosure provides an aircraft frame that can be retrofitted to existing microlight as well as flex wing aircrafts without any major design alterations.