Apparatus for Folding a Sheet of Material Into a Support Structure

Apparatus and methods for forming three dimensional structures from a sheet of material of a desired medium are described. Examples described include an apparatus for folding a sheet of material to create a folded structure, the apparatus having a first and second array of creasing elements, and at least one actuator for causing relative movement of the first and second array of creasing elements from a first position to a second position.

TECHNICAL FIELD

This present disclosure relates to apparatus for folding a sheet of material, and more particularly apparatus for folding a sheet of material into a three dimensional structure.

BACKGROUND

Sandwiched structures are known in the art. Some sandwich structures are formed using corrugated materials, which may be fluted by passing a material between rollers. Other sandwiched structures may be formed using core materials, for example honeycomb cores or foam cores, which may be sandwiched or disposed between one or more ply sheets or external liners.

However, conventional sandwich structures exhibit many drawback in strength, rigidity, weight, and durability. Improved three dimensional support structures have been introduced, as described in U.S. Pat. No. 7,762,932, which is incorporated herein in its entirety by this reference for any purpose. Instead of corrugating the core or inner medium of the structure, the three dimensional support structures described in U.S. Pat. No. 7,762,932 are generally formed by folding a sheet of medium, which may be paper or other foldable medium, into a three dimensional structure.

While certain processes for large scale production of corrugated structures may be known, methods and apparatus for obtaining folded three dimensional structures in an automated fashion are not currently available. The present disclosure may address some or all of the shortcomings in the art.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative examples described in the detailed description, drawings, and claims are not meant to be limiting. Other examples may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are implicitly contemplated herein.

Apparatus, systems and methods for folding a sheet of material into a folded support structure are described herein, which apparatus, systems, and methods, as will be appreciated, lend themselves to a level of automation. An exemplary apparatus includes a first array of creasing elements and a second array of creasing elements, each of the creasing elements in the first and second arrays having a leading edge adapted to engage a sheet of material. The apparatus further includes at least one first actuator for causing relative movement of the first and second arrays of creasing elements from a first position in which the first and second plurality of creasing elements are spaced apart to a second position in which the first and second array of creasing elements are at least partially interdigitated whereby the sheet of material can be placed between the first and second arrays of creasing elements and folded by the leading edges of the creasing elements during the relative movement of the first and second arrays creasing elements to the second position. The apparatus also includes at least one second actuator for moving the creasing elements of the first array closer together and the creasing elements of the second array closer together during relative movement of the first and second arrays of creasing elements to the second position whereby the movement of the creasing elements of the first array closer together and the creasing elements of the second array closer together accommodates contraction of the sheet of material as it is folded by the first and second arrays of creasing elements.

An exemplary apparatus for folding a sheet of material into a support structure according to the present invention is illustrated inFIGS. 1-4. Exemplary folding apparatus1therein may include a support structure3, an actuation assembly5including a plurality of actuators, and a creasing assembly7including a first or top array10of creasing elements and a second or bottom array12of creasing elements. The support structure3generally includes any structural features provided for supporting and maintaining the relative positioning between components of the actuation assembly5and creasing assemblies7. The actuation assembly5can include an suitable actuation device such as a pump, motor or other mechanical or electrical actuator adapted for generating and providing the desired movement of the components of the creasing assembly7, for example the movement of creasing arrays10,12and creasing elements relative to each other. In the context of this disclosure, creasing elements may interchangeably be referred to as folding elements and accordingly, the term “folding element” is an alternate term for “creasing element.” The creasing assembly7includes structures configured to engage with a folding medium to obtain a folded three dimensional structure as will be described.

In the creasing assembly7, a first array10of creasing elements and a second array12of creasing element including a respective plurality of individual top creasing elements13and bottom creasing elements14can be provided, each creasing element13,14being configured to engage with a foldable medium during operation of the apparatus1to fold the medium according to a desired pattern. In the exemplary apparatus1, the creasing assembly7has a first or top array10of creasing elements13and a second or bottom array12of creasing elements14, each as described in further detail below. As will be understood, designations of relative positioning such as “top,” “bottom,” “left,” “right,” and similar identifiers are used herein only for the purposes of facilitating the description of the examples disclosed herein and are not to be taken in a limiting sense.

The support structure3may include a plurality of support elements or members, which can include platforms or plates, which may be generally rigid and used to mount various components of the actuation assembly5and creasing assembly7thereto. A first or top support member or plate2and a second or bottom support member or plate4may remain stationary relative to each other during the operation of the device, and accordingly may be respectively referred to herein as stationary top platform2and a stationary base platform4. A third or intermediate support member or plate6may be provided between the top plate2and bottom plate4. The third or intermediate plate6may be configured to move relative to the first and/or second plates2,4during operation of the folding apparatus1. In one embodiment, illustrated inFIG. 1, first plate2, second plate4, and intermediate plate6are each generally rectangular in shape and each extend in the x-y plane, noted inFIG. 1, and are disposed in spaced-apart positions along the z axis and generally parallel to each other. In one embodiment, intermediate or moveable plate6is movable along the z axis or vertical direction15relative to and between both top plate2and bottom plate4. Each of the plates2,4,6may be made from any suitable rigid material such as metal, plastic or ceramic. It is appreciated that other form factors and relative arrangement may be used in other embodiments of the invention.

The support structure3may also include one or more support members9. The support members may be implemented as posts or columns11extending between the top plate2and the bottom plate4. The guide columns11are mounted or secured to and support the top plate4in a fixed position relative to the bottom plate2. Each of the columns has a first or top end secured to top plate2and a second or bottom end secured to bottom plate4. The columns11may, in some examples, be used as vertical movement guides for the vertical movement of the intermediate plate6relative to and between the plates2,4. In one embodiment, four support members or columns11are provided, one at each corner of plates2,4and as shown inFIGS. 1-3, however it is appreciated that any number of support members11may be used as desired or suitable for the particular application. In some examples the plates or platforms2,4,6may be circular, for example, and different number of columns, for example three in number, or in some examples six or eight columns may be used to maintain the plates in the desired configuration. It is appreciated that other mechanisms, structures, guides or elements may be provided for permitting intermediate plate6to move relative to top and bottom plates2,4and for guiding the intermediate plate6during such movement.

The intermediate plate6, which is provided between the first plate2and second plate4, is configured to move in the vertical direction15, for example the direction perpendicular to the respective planes of top and bottom plates2,4and thus along the z axis or vertical direction15, during the operation of exemplary apparatus1. A plurality of apertures or openings may be provided through the thickness of the intermediate plate6such that the columns11can pass through the plate6and the plate6can move up and down, using the columns11as guides. Each of the apertures may include a bearing assembly or any other conventional sliding contact mechanism (not shown) for slidingly coupling the support member within the aperture to the intermediate plate6. The bearing may be selected such that it provides a nominally frictionless contact between surfaces of the columns11and the apertures. In some examples, one or more surfaces of the apertures and/or columns may be treated or otherwise coated with a low-friction coating to reduce friction between and minimize wear of the surfaces of the columns11and apertures as the plate6moves up and down. In one embodiment, some or all of the columns11are cylindrical and the apertures in plate6are circular, although it is appreciated that other cooperatively engaging cross-sectional configurations, such as oval, rectangular or square, can be provided.

In one embodiment, a plurality of linear actuators, for example cylinder-piston type, hydraulic or electric actuators, may be used instead of the stationary support members or columns11. That is, in some examples, a first plurality of pistons or actuators (not shown) may be provided between the first plate2and the intermediate plate6and a second plurality of pistons (non shown) may be provided between the intermediate plate6and the second plate4. The movement of the linear actuators may be controlled and/or synchronized as desired, using a programmable controller for example, to provide coordinated movement of such actuators and thus corresponding movement of the intermediate plate6along the z axis or vertical direction15.

Actuation assembly5may generally include actuation devices for causing relative movement between the first array10and the second array12between a first or home position where the first array10and second array12are spaced apart, as shown for example inFIGS. 2,3,16,17,19and20, and a second position where the creasing elements of the first array10and second array12are interdigitated, as shown for example inFIGS. 21,23and24. In the example inFIGS. 1-3, by virtue of the arrays10,12being mounted to two separate respective plates or platforms, movement of the arrays10,12towards or away from each other is achieved by one or more actuators configured to move one or both of such plates towards or away from each other. In one embodiment, first array10is mounted on the intermediate plate6, for example on the lower or inner-facing surface of the intermediate plate6, and second array12is mounted on bottom plate4, for example on the upper or inner-facing surface of the bottom plate4and thus arrays10,12face or are opposed to each other. The actuators of actuation assembly5can serve to cause intermediate plate6to move downwardly or towards bottom plate4, or cause bottom plate4to move upwardly or towards intermediate plate6, or both. In one embodiment the actuation assembly5moves intermediate plate6downwardly relative to bottom plate4, and top plate2, and the bottom and top plates4,2remain stationary, and in this manner first or top array10is moved from a first or home position in which the creasing elements13of the top array are spaced from the creasing elements14of the bottom array12to a second position in which the creasing elements13of the top array10are at least partially interdigitated with the creasing elements14of the bottom array12. The actuation assembly5may also include actuation devices configured to move the creasing element13,14and/or arrays10,12in the x-y plane, for example longitudinally and laterally.

An exemplary operation of the apparatus will be briefly described to further aid in understanding the components and functions of the actuation assembly. Generally, during operation, the first array10and second array12and respective individual creasing elements or folding elements13,14of the arrays are configured to move along the x and y directions. At some stages of a folding operation the individual creasing elements, for example creasing elements or folding elements13and14, of the first array10and the second array12move between a first or fully expanded position, as illustrated inFIG. 4, and a second or fully contracted position, as illustrated inFIG. 25. In the fully expanded or home position, the creasing elements13,14are spaced farther apart from each other more than when the creasing elements are in the fully contracted position, in which the creasing elements are closer together. In one embodiment, for example as shown inFIGS. 25-30, adjacent creasing elements are at least nearly touching each other and can in fact touch each other when the respective array is in the fully contracted position. Accordingly in some instances, the first or top array10and/or the second or bottom array12may be said to be in an expanded configuration, for example when the creasing elements are spaced apart, or in a collapsed configuration, for example when the creasing elements are close together. The arrays10and12can pass through several intermediate stages of being partially expanded or collapsed along the x and y directions when moving between such first and second positions. Contraction and expansion of the creasing elements of an array10,12in the x direction can be coordinated with or independent of the contraction and expansion of such creasing elements in the y direction. In addition, contraction and expansion of creasing elements13in one array10and can be coordinated with or independent of the contraction and expansion of creasing elements14in the other array12.

In addition, the first or top array10is also configured to translate or move up and down, that is along the z axis and vertical direction15, relative to the second or bottom array12(seeFIGS. 1-3). At some stages of a folding operation the individual creasing elements, for example creasing elements13and14, of the first array10and the second array12move relative to each other between a first or spaced-apart or non-interdigitated position, as illustrated inFIGS. 1-3,16-17, and a second or fully interdigitated position, as illustrated inFIGS. 28-30. In the first expanded position, the creasing elements13,14are spaced farther apart from each other and the leading edges120of the creasing elements13are not interdigitated with the leading edges122of the creasing elements14. In one embodiment, for example as shown inFIGS. 28-30, the top portion150of the creasing elements13are fully interdigitated with the top portion150of creasing elements14when the arrays10,12are fully interdigitated relative to or with each other. In one embodiment, the inclined surfaces124,126of creasings elements13are in contact with or in closed proximity to and substantially parallel to the opposed inclined surfaces124,126of the creasing elements14when the arrays10,12are fully interdigitated relative to each other. The arrays10and12can pass through several intermediate stages of being partially interdigitated in z direction when moving between such first and second positions. Interdigitation of the arrays10,12in the z direction can be coordinated with or independent of the contraction and expansion one or both of the arrays in the x direction and in the y direction. For example, the relative movement of the arrays10,12can be coordinated such that the arrays are fully contracted in the x and y directions and when the arrays are fully interdigitated in the z direction. It is appreciated that many combinations of independent or coordinated movement of the creasing elements or folding elements of one array in the x, y and z directions, or of the creasing elements or folding elements of both arrays in the x, y and z directions, can be provided by apparatus1.

Movement of the arrays10,12and creasing elements13,14along the x and/or y direction is provided by one or more array actuation assemblies or devices22. Movement in the vertical direction15of one or more of the arrays is provided using one or more plate actuation assemblies or devices25. This combination of array and plate actuation devices or actuators is configured to provide three-degrees of freedom of the creasing elements13,14of each of the arrays10,12, for example movement along all three of the x, y and z axes, such that each creasing element in an array10or12is moveable along the x, y, and z axes relative to the creasing elements in the other array12or10. Hence, for example, each creasing element13in the top array10is movable along all three orthogonal x, y and z axes relative to the creasing elements14in the bottom array12. In one embodiment, creasing elements13,14are restrained from rotational movement along all of the axes, however it is appreciated that arrays of creasing elements may be provided that rotate or pivot along one or any combination of axes such that various curved structures may be manipulated or formed using the apparatus described herein.

Generally, the arrays10,12and individual creasing elements13,14are configured for linear motion along the x, y and z axes according to a desired timing or sequence to achieve the folding of a sheet of material into a folded support structure, as will be described herein. The timing and sequence of relative motion of the arrays and creasing elements may be controlled with one or more manual or programmable controllers (not shown), which are operatively coupled for example by hard wiring or wireless communication to the actuation assembly5.

In one embodiment, plate actuation may be accomplished by a plate actuation assembly or device25that includes one or more linear actuators8, for example piston-type actuator that can be hydraulic, pneumatic or electric or any other linear actuators currently known or later developed. In the present example, a single actuator8having a housing8aand a piston8bthat is extendable from the housing8ain a linear manner is used, with the first or free end of the piston8bsecured to the intermediate or moveable plate6and the housing8abeing secured to the top plate2. In this manner, as the first end of the piston8bmoves away from or extends from the actuator housing8a, plate6is translated or moved downwardly on columns11along the z direction to a position closer to the bottom plate4, thus contracting the creasing assembly7in the z direction by causing the creasing elements13of the top array10to interdigitate with the creasing elements14of the bottom array12. When the piston8bretracts into the housing8a, moveable plate6is translated or moved upwardly and away from the bottom plate4, thus expanding the creasing assembly7along the z direction by causing the creasing elements13of the top array10to move away from the creasing elements14of the bottom array12.

As will be appreciated, in some examples, any number of actuators8may be used in plate actuation device or assembly25. For example, in other embodiments, two or more actuators8, and in some embodiments smaller actuators8, may be used in place of a single central actuator8. In other examples, four actuators8may be used, which may for example be located at each corner of the apparatus1, such as at each corner of top plate2and intermediate plate6. As previously described, in some examples, the linear actuation of the plate6may be achieved by replacing the support members or columns11with active components, for example linear actuators. In one embodiment (not shown), a rack and pinion gearing mechanism may be used to provide linear actuation of the intermediate plate6. Any other actuation devices8currently known or later developed may be used to move the plate6and thus move the arrays10,12closer together and farther apart, that is provide vertical movement of one or both of the arrays10,12.

The actuation assembly5may also include an array actuation assembly or device22for providing movement of the first array10and second array12of creasing elements13,14and the individual creasing elements13,14along the x and/or y directions, for example lateral and/or longitudinal movement in the x-y plane. Array actuation assembly22may be implemented using any combination of hydraulic, pneumatic or electrical actuators, piston-type or otherwise. In some examples, the array actuation assembly22may include one or more hydraulically or pneumatically-driven rotary actuators. In some examples, electrical motors or other electrical actuators may be used to provide the desired movement of the arrays10,12and associated creasing elements13,14in the x-y plane. The x-y plane, as used in the context of the present disclosure, is meant to refer to some reference x-y plane, for example the x-y plane illustrated inFIG. 1, as well as any plane parallel to such reference x-y plane.

In one embodiment of apparatus1, array actuation assembly22for causing longitudinal and lateral actuation of the arrays10,12of creasing elements includes a plurality of rotary actuators, such as first or top rotary actuators18and second or bottom actuators20. The array actuation assembly may, in addition, include a plurality motion converters or transmission mechanisms, such as first or top gear mechanisms42and second or bottom gear mechanism45, for converting the rotation of the shafts of the respective actuators18,20to linear motion. The gear mechanisms42,45may be of the rack and pinion type, and in one embodiment may include a central gear or pinion and a pair of linear bar gears or racks, each of the pair of racks being disposed on opposite sides of the pinion gear and engaged with the teeth of the pinion gear. The components of each of gear mechanisms42,45may be made from any suitable material such as metal or plastic. In one embodiment of apparatus1, four rotary top actuators18are mounted to the intermediate plate6and move up and down with the plate6and four rotary bottom actuators20are mounted on the bottom plate2, and remain stationary with such plate2. Each of the plurality of actuators18and20is configured to rotate a one of the circular gears or pinions of the respective rack and pinion assemblies42and45to cause the related bar gear or rack of the respective rack and pinion assembly42and45to translate along the x or y directions. In some embodiments, certain coupling devices may be used, if desired, to couple the rotation of a single actuator to a plurality of rack and pinion assemblies, such that fewer number of actuators may be needed.

FIGS. 4, and11-13show perspective, side, and top views of the bottom half1aof the folding apparatus1, and specifically bottom plate4, bottom actuators20, bottom rack and pinion assemblies45and bottom array12mounted on the bottom plate4and more particularly carried by the bottom rack and pinion assemblies45. The bottom half assembly1aincludes four rotary actuators20as described above and four sets of rack and pinion gears45a,45b,45cand45d, described in further detail below. A first bottom rack and pinion gear assembly45a, which is arranged along the x axis and adapted for x movement, includes a first x-pinion17and a first pair of x-racks including inner bar gear or rack19and outer bar gear or rack21. The first pair of x-racks are provided on a first pair of x-rails. That is, the inner rack19is slidably coupled to inner rail23and outer rack21is slidably coupled to outer rail24in each case for example by a set of bearing mechanisms or bearings40. Any bearing mechanism currently known or later developed may be used to slidably couple the inner and outer racks17,19to the respective inner and outer rails23,24. The x-rails23and24may be rigidly mounted by any suitable means, for example by being bolted, welded or otherwise affixed, to bottom plate or platform2. The first x-pinion17is coupled to and rotated by a first rotary actuator20aduring operation of the array actuation assembly or device22, said rotation being transmitted to the racks19,21which are configured to slide along the x-rails in the x direction, as shown for example by comparison ofFIG. 4andFIG. 25. During such movement or translation, the outer gear teeth on pinion17are rotated by actuator20aand mesh with the respective teeth of racks19,24to cause the racks to slide or move in opposite linear directions on the respective rails23,24, either towards each other in a contraction motion of the assembly45aor away from each other in an extension motion of the assembly45a.

A second bottom rack and pinion gear assembly45cis also arranged along the x axis and adapted for x movement. The second rack and pinion gear assembly45cis disposed generally opposite the first bottom rack and pinion gear assembly45a, that is on the opposing side of the bottom array12of creasing elements13. The second gear assembly45cis substantially similar in construction and operation to first gear assembly45aand includes a second x-pinion37and a second pair of x-racks including second inner bar gear or rack39and second outer bar gear or rack41. The second pair of x-racks are provided on a second pair of x-rails, the rails being mounted to plate2. That is, the second inner rack39is slidable coupled to second inner rail43and second outer rack41is coupled to second outer rail44by any suitable means such as by respective sets of bearings40. The second x-pinion37is coupled to and rotated by a rotary actuator20cduring operation of the device, and rotation of the pinion37is used to translate the racks39and41in x direction in the manner discussed above with respect to first bottom rack and pinion gear assembly45c.

Two additional rack and pinion gear assemblies45b,45d, each substantially similar to assemblies45aand45c, may be provided along the y direction and adapted for y movement in a direction perpendicular to the movement of assemblies45aand45c. A third rack and pinion gear assembly45bincludes a third pinion gear or first y-pinion gear27and a third pair of racks also known as first pair of y-racks, including third inner bar gear or rack28and third outer bar gear or rack26. Similar to the gear assembly45a, the racks28and26are slidably coupled or engaged with a third pair of rails also referred to as a first pair of y-rails, such as third inner rail29and third outer rail30, by any suitable means such as a by respective sets of bearings40, and the racks28and26are configured to traverse along the y direction in response to the rotation of third actuator80bthat is connected to third pinion gear27in the manner discussed above with respect to first bottom rack and pinion gear assembly45d. Similarly, a fourth rack and pinion assembly45dis provided on the opposite side of the bottom array12of creasing elements14from the third rack and pinion gear assembly45b. Fourth rack and pinion gear assembly45dincludes a fourth pinion gear or first y-pinion gear47and a fourth pair of racks also known as second pair of y-racks, including fourth inner bar gear or rack48and fourth outer bar gear or rack46. Similar to the third gear assembly45b, the racks48and46are slidably coupled or engaged with a fourth pair of rails also referred to as a second pair of y-rails, such as fourth inner rail49and fourth outer rail50, by any suitable means such as a by respective sets of bearings40, and the racks48and46are configured to traverse along the y direction in response to the rotation of fourth actuator80dthat is connected to third pinion gear47in the manner discussed above with respect to first bottom rack and pinion gear assembly45d.

The actuation assembly22may further include a plurality of x-push/pull or translation bars51,52and y-push/pull or translation bars53,54, operatively coupled to the bottom array12and configured to collapse the array12. In one embodiment, each of the push/pull or translation bars51-54may be a generally elongate members which is coupled at its opposite ends to opposite respective rack gears, such as opposite sets of the racks discussed above. The push/pull bars may also be coupled to the sides of the bottom array12, or may be otherwise configured to apply a generally inward force to cause the bottom array12, under the force of the rack and pinion assemblies discussed above, to contract or collapse. The push/pull bars also apply a generally outward force to cause the bottom array12, under the force of the rack and pinion assemblies discussed above, to expand.

In one embodiment, as shown inFIG. 12, a first x-push/pull bar51is disposed such that a longitudinal direction of the push/pull bar51extends in the y direction. The push/pull bar51is attached at a first end to the top of one end of the outer rack21of the first rack and pinion assembly45aand is attached at its opposite second end to the top of an end of the inner rack39of the second rack and pinion assembly45c, in each case by any suitable means such as an adhesive or one or more fasteners. The central portion of the bar51abuts a side, such as the left side inFIG. 12, of the bottom array12and is attached to such side of array12by at least one and in one embodiment a plurality of first y-guides57which are each connected to the bar51and to one of the creasing elements14of the array12. As such, coordinated rotation of first and second actuators20aand20cin a counterclockwise direction inFIG. 12result in coordinated movement of the racks21and39in the x direction so as to cause the first x-push/pull bar51to translate, push or move in the x direction and thus urge the left side of the bottom array12to the right. A second x-push/pull bar52similarly extends in the y direction and is attached at its first end to the top of one end of the inner rack19of the first rack and pinion assembly45aand is attached at its opposite second end to the top of an end of the outer rack41of the second rack and pinion assembly45c, in each case by any suitable means such as an adhesive or one or more fasteners. The central portion of the second x-push/pull bar52abuts a side, such as the right side inFIG. 12, of the bottom array12and is attached to such side of array12by at least one and in one embodiment a plurality of second y-guides58which are each connected to the bar52and to one of the creasing elements14of the array12. Coordinated movement of the racks19and41, resulting from the foregoing coordinated rotation of first and second actuators20aand20cin a counterclockwise direction inFIG. 12, causes the push/pull bar52to translate, push or move in the x direction thereby bringing, sweeping or urging the entire right side of the bottom array12to the left or first x-push/pull bar51.

In a similar manner, a first y-push/pull bar53and a second y-push/pull bar54may be coupled to and extend between the rack and pinion assemblies45band45d. More specifically, the first y-push/pull bar53is attached at a first end to the top of one end of the outer rack26of the third rack and pinion assembly45band is attached at its opposite second end to the top of an end of the inner rack38of the fourth rack and pinion assembly45d, in each case by any suitable means such as an adhesive or one or more fasteners. The central portion of the bar53abuts a side, such as the front side inFIG. 12, of the bottom array12and is attached to such side of array12by at least one and in one embodiment a plurality of first x-guides55which are each connected to the bar53and to one of the creasing elements14of the array12. As such, coordinated rotation of third and fourth actuators20band20din a counterclockwise direction inFIG. 12result in coordinated movement of the racks26and48in the y direction so as to cause the first y-push/pull bar53to translate, push or move in the y direction and thus urge the front of the bottom array12to the rear. The second y-push/pull bar54similarly extends in the x direction and is attached at its first end to the top of one end of the inner rack28of the third rack and pinion assembly45band is attached at its opposite second end an end to the top of the outer rack46of the fourth rack and pinion assembly45d, in each case by any suitable means such as an adhesive or one or more fasteners. The central portion of the second y-push/pull bar54abuts a side, such as the back side or rear inFIG. 12, of the bottom array12and is attached to such side of array12by at least one and in one embodiment a plurality of second x-guides56which are each connected to the bar54and to one of the creasing elements14of the array12. Coordinated movement of the racks28and46, resulting from the foregoing coordinated rotation of third and fourth actuators20band20din a counterclockwise direction inFIG. 12, causes the push/pull bar54to translate, push or move in the x direction thereby bringing, sweeping or urging the entire back side of the bottom array12towards the front or first y-push/pull bar53. Third rack and pinion assembly45band fourth rack and pinion assembly45dare positioned higher in the z plane relative to bottom plate4, and first y-push/pull bar53and second y-push/pull bar54mounted to and extending between assemblies45band45dare positioned higher that first x-push/pull bar51and second x-push/pull bar52so that the travel of the y-push/pull bars53and54does not interfere with the travel of the x-push/pull bars51and52.

One or more guides coupled to the intermediate portions of the bottom array12may be provided for facilitating the uniform expansion and contraction of the bottom array12in the x and y directions. In one embodiment, a plurality of the first x-guides55may be slidably coupled to first y-push/pull bar53and a plurality of the second x-guides56may be slidably coupled to second y-push/pull bar54. A first x-slide bar59acan be provided on or mounted to the first y-push/pull bar53for slidably carrying the first x-guides55, which can each be slidably coupled or carried by the first x-slide bar by any suitable means such as a bearing. Similarly, a second x-slide bar59ccan be provided on or mounted to the second y-push/pull bar54for slidably carrying the second x-guides56, which can each be slidably coupled or carried by the second x-slide bar by any suitable means such as a bearing. Respective pairs of first x-guides55and second x-guides56can be secured to opposite ends of certain of the columns of creasing elements14of the bottom array12. In this manner, one or more of the first x-guides55and second x-guides56may slide or travel over or on respective x-slide bars or rails59a,59cwhen the array12is contracted or expanded in the x direction. In one embodiment illustrated in the drawings and shown for example inFIG. 12, a pair of guides55,56is respectively secured to the bottom and top of each of the left-most column of creasing elements14, the right-most column of creasing elements14, a left intermediate column of creasing elements14and a right intermediate column of creasing elements14.

In a similar manner, a plurality of the first y-guides57may be slidably coupled to first x-push/pull bar51and a plurality of the second y-guides58may be slidably coupled to second x-push/pull bar52. A first y-slide bar59dcan be provided on or mounted to the first x-push/pull bar51for slidably carrying the first y-guides57, which can each be slidably coupled or carried by the first y-slide bar by any suitable means such as a bearing. Similarly, a second y-slide bar59bcan be provided on or mounted to the second x-push/pull bar52for slidably carrying the second y-guides58, which can each be slidably coupled or carried by the second y-slide bar by any suitable means such as a bearing. Respective pairs of first y-guides57and second y-guides58can be secured to opposite ends of certain of the rows of creasing elements14of the bottom array12. In this manner, one or more of the first y-guides57and second y-guides58may be adapted to slide or travel over or on respective y-slide bars or rails59b,59dwhen the array12is contracted or expanded in the y direction. In one embodiment illustrated in the drawings and shown for example inFIG. 12, a pair of y-guides57,58is respectively secured to the left and right of each of the top-most row of creasing elements14and the bottom-most row of creasing elements14. The plurality of x-guides55,56may extend relative to the y-push/pull bars in a first direction along the z axis, for example in an upward direction, for attaching to the respective creasing elements, while the plurality of y-guides57,58may extend relative the x-push/pull bars in a second opposite direction along the z axis, for example a downward direction, for attaching to the respective creasing elements. In this manner, the x-guides and y-guides may slide along respective rails or slide-bars without interfering with each other. Interaction between the push/pull bars, guides and the creasing elements of the array will be described in further detail below.

As will be understood, during typical operation of the device, the pair of x-push/pull bars51and52generally move in a coordinated manner either towards each other or away from each other from the rotation of the first and second pinion gears17,37, respectively driven by first and second actuators20a,20c, which translate the respective sets of outer and inner racks21,29and inner and outer rack19,41. That is, during normal operation of the device, either the left or first push/pull bar51will move to the right while the right or second push/pull bar52will move to the left applying a generally inward or compressive force to the opposite left and right sides of the array12in the x direction. After such partial or complete contraction of the bottom array12, the left or first push/pull bar51will move to the left while the right or second push/pull bar52will move to the right applying a generally outward or tensile force to the opposite left and right sides of the array12in the x direction so as to pull the pull the creasing elements14apart thus expand the array12. In a manner similar to the discussion with respect to x contraction and expansion of bottom array12, coordinated movement of the racks26,24and racks28,46, driven respectively by pinions27,47and actuators20b,20d, may similarly drive or sweep the longitudinal push/pull bars53and54towards or away from each other such that they collapse or expand the bottom array12in the y direction. In one embodiment, such operation, as discussed below, results in either one-to-one contraction or one-to-one expansion of the creasing elements14in the bottom array12in both the x and y directions when viewed in plan, for example as illustrated inFIG. 12, and in one embodiment the movement of the array12in the x direction is coordinated with the movement of the array12in the y direction such that the contraction or expansion in the x direction is one-to-one with the contraction or expansion in the y direction. Guides55-58serve to secure the respective bars53,54,51,52to the sides of the array, to facilitate even expansion and contraction of the array and to minimize unwanted movement or distortion of all or any portion of the array along the z axis. Although in the illustrated embodiment the rack and pinion assemblies42,45are adapted to generate coordinated movement of respective pairs of push/pull bars, for example bars51and52move in unison and bar53and54move in unison, other actuation assemblies may be implemented to allow each individual push/pull bar to traverse its respective direction independently. For example, instead of rack and pinion gears, each individual push/pull bar may be coupled to a separate actuator, thus each push/pull bar may be individually driven to cause one or more of the sides of the arrays to move to a different extent than other sides of the array.

In one embodiment, top array10is substantially identical to bottom array12, and the actuation assembly22for the top array10is substantially identical to the actuation assembly22for the bottom array12. In one embodiment, first through fourth top actuators18a-18dare substantially identical to respective first through fourth bottom actuators20a-20dand are respectively coupled to first through fourth rack and pinion assemblies or other suitable gear mechanisms42a-42dthat are substantially identical to respective first through fourth bottom rack and pinion assemblies45a-45d. In one embodiment, the top actuators18a-dand rack and pinion assemblies42a-dare aligned or registered opposite the respective bottom actuators20a-dbottom rack and pinion assemblies45a-d, as shown for example inFIG. 3. In one embodiment the top actuation assembly22further includes x and y push/pull bars and guides substantially identical to the x and y push/pull bars and guides discussed above with respect to the bottom array12. The top actuation assembly22can operate with respect to the top array10in substantially the same manner as discussed above with respect to the operation of the bottom actuation assembly with respect to the bottom array12. Like reference numerals have been used herein to describe and identify like components of top actuation assembly22and bottom actuation assembly22.

Other form factors, assemblies or mechanisms for providing the desired horizontal motion of the arrays, for example along the x and y directions, may be used. In this regard, other assemblies or mechanisms, for example pulleys and drive belts, may be used in place of or in combination with gears for transmitting the motion generated by the power generation components, for example by actuators20or such other suitable pumps, motors or pistons, of the actuation assembly22. In some embodiments for example, x and y actuation or movement of the bottom array12may be driven directly by one or more electrical motors such that the actuation assembly22does not include any gears, such as rack and pinion assemblies42and45, or pulleys.

As can be observed inFIG. 2, the first or top array10and the second or bottom array12are disposed such that rows of respective creasing elements13,14are aligned in the y axis, while as can be seen fromFIG. 3the top array10and the bottom array12are disposed such that top and bottom columns31,32of respective creasing elements13,14are not aligned in the x axis, as will be described in greater detail below. That is, as shown inFIG. 2, each of the plurality of first or top columns31of creasing elements13is offset to either the right or left of each of the plurality of second or bottom columns32of creasing elements14. In one embodiment, the top array10has one less column31than the bottom array12(seeFIG. 2). As shown inFIG. 3, each of the plurality of first or top rows33of creasing elements13is in line with each of the plurality of second or bottom rows34of creasing elements14. In one embodiment, the number or rows33in the top array10is equal to the number of rows34in the bottom array12. The creasing elements13,14of each array10,12may be regularly spaced relative to each other, such that the relative spacing between adjacent top columns31and between adjacent bottom columns32, as well as the offset between adjacent top and bottom columns31,32may be the same, that is equal spacing between columns, as well as equal offset distances between top and bottom columns, as shown inFIG. 2. Similarly, the relative spacing between adjacent top rows33may and between adjacent bottom rows34may be the equal.

In some examples, the columns of creasing elements of one of the arrays, for example the columns31of the first array10, may be substantially centered between the columns of the other array, for example the columns32of the second array12. In some examples, the creasing elements may not be regularly spaced in that some columns of creasing elements may be closer together than other columns of creasing elements and thereby the apparatus being operable to achieve different spacing between the resulting cells of the folded structures as will be further described and appreciated in view of the present disclosure. As can be observed inFIG. 3, at some stages of the operation of apparatus1respective rows33,34of creasing elements are aligned in that a first or top row33of creasing elements13is in the same x-z plane as a corresponding second or bottom row34of creasing element14. However, as each of the top and bottom creasing arrays10,12have their own independent actuation assemblies22, each of the top and bottom arrays10,12can move, for example expand or contract, relative to each other and independent of each other in the x-y plane. Further, during certain stages of operation in some embodiments, the rows33of creasing elements or folding elements of the first array10may or may not be aligned with rows34of the creasing elements or folding elements of the second array12. In addition, the independent actuation assemblies22permit the second array to expand or contract in the x direction independently of any expansion or contraction of the array in the y direction.

As discussed above, the apparatus1may include one or more controllers operatively coupled to the one or more of the actuation devices or assemblies5of apparatus1, for example actuators8,18and20. The one or more controllers (not shown) may be programmable to translate, using the actuation assembly22, the arrays10,12of creasing elements13,14according to a predetermined sequence of directions and steps to achieve the folding of the medium.

An exemplary foldable medium60, and three dimensional support structure61, which may be formed using the apparatus and methods disclosed herein, are now described with reference toFIGS. 5-10. Various three dimensional support structures can be formed using the systems and methods disclosed, examples of which are described in U.S. Pat. No. 7,762,938 to Gale, which patent is incorporated herein by this reference in its entirety for any purpose. In some examples, three dimensional structures may be formed by folding one or more sheets of a flexible material, for example folding medium60, into a variety of patterns. The flexible material or medium60may be paper, or other cellulose products, metal, plastic, composite or other materials. The material60may be of varying grade and thickness, and may be selected from a variety of currently commercially available or later developed products based upon user preferences.

In some examples, a tessellation of generally rectangular folded regions, for example cells63, is defined, as will be further described. However, in some examples, substantially any shapes or patterns can be achieved depending on the desired three dimensional support structure and particular implementation of individual creasing elements13,14and arrays10,12of creasing elements utilized. In some examples, the array or tessellation of cells may define a regular pattern, or in examples, the cells may be irregularly arranged. Some cells may have a different size than other cells within the same tessellation. For example, groups of narrow cells may be interspersed between groups of wider cells such that additional stiffness or rigidity is imparted to the folded structure in the regions where the narrow cells are located. Other variations will be appreciated in light of the present disclosure and may be implemented without departing from the scope of the present invention.

In some examples, the three-dimensional support structures61, interchangeably referred to as folded structures herein, may be used in the manufacture and composition of packaging materials and other support structures, used for example in fuselages, wings, bulkheads, floor panels, construction panels, refrigerators, ceiling tiles, intermodal containers, and seismic walls. For example, the folded three-dimensional support structures of the present invention can be used in place of or in addition to conventional core materials, such as foam core or honeycomb core materials used in certain sandwich structures. However, other three dimensional structures for other applications can be implemented according to the present disclosure and additional advantages to the ones described will be appreciated in light of the present disclosure.

As will be described in further detail below, the folded structures61according to the present disclosure may be formed by folding the folding medium60in multiple directions so as to form vertical structures in three planar orientations, namely, the x, y and z-axes. In some examples, the three-dimensional structures are formed from a single sheet of material or folding medium60which is folded into a repeating pattern of cells63when viewed both from a first side or top, as shown inFIG. 7, and from a second side or bottom, as shown inFIG. 8. Each of the cells63is formed by and includes first and second spaced-apart endwalls72,74and first and second sloped sidewalls or facets76,78spanning between the endwalls. In one embodiment, the first and second spaced-apart endwalls72,74of the folded structure lie parallel to the x-z plane, while the first and second sloped sidewalls76,78are disposed at an angle to the y-z plane and the x-z plane (seeFIGS. 7 and 8).

Each of the endwalls72,74includes at least two plies of the material60and each of the sidewalls76,78includes at least a single ply of the material60. In the embodiment of the folded structure61illustrated herein, each of the endwalls72,74is formed of two plies of material60and each of the sidewalls76,78is formed from a single ply of the material60. First and second sidewalls76,78of adjacent cells63are adjoined at a folded edge80. The cells63are further aligned so that the first endwall72of one cell63from the repeating pattern abuts the second endwall74of an adjacent cell63from the repeating pattern to form at least a four-ply wall82of the material60. When structure61is viewed from a first side, as shown inFIG. 7, the repeating cells63define a first surface62having a trough or valley86therein, and when the structure is viewed from an opposite second side, as shown inFIG. 8, the repeating cells63define a second surface64having a trough or valley86therein. The first and second surfaces62,64are each planar and parallel to the x-y reference plane of the three dimensional structure61and to each other. The folding medium60, when folded into the desired pattern of repeating cells63, defines a pattern of rails65, which may be used to support and/or for attachment of an optional first liner (not shown) on first surface62and an optional second liner (not shown) on second surface64. That is, a first plurality of rails65ais formed on the first surface62and a second plurality of rails65bis formed on the second surface64. The first and second plurality of rails65a,65bin combination with the respective folded edges80of such surfaces62,64form first and second spaced-apart grid like patterns which lie in parallel x-y planes. Accordingly, one or more optional liners may be supported to and/or attached to the folded structure along the grid like patterns. Thus, one or more optional lines may be adapted to lie generally in-plane with the surfaces62,64, and parallel to the x-y reference plane.

In some examples, the pattern of repeating cells63includes the four-ply wall structure82as described above, and a repeating pattern of ascending facets or sloped sidewalls78and descending facets or sloped sidewalls76(seeFIGS. 6-8). As depicted inFIG. 6showing a partially folded medium and inFIGS. 7 and 8showing a fully folded structure, the plurality of adjoining sloped sidewall76,78, when viewed along the y direction, alternate in a pattern of ascending and descending sloped sidewalls relative to the x-z plane. Adjacent ascending facet or sloped sidewall78and descending facet or sloped sidewall76form a plurality of apexes or peaks80and a plurality of troughs or recesses86. Adjoining facets76and78meet at ridge or peak80to define the peak or top fold80, and also meet at the bottom of trough or valley, to define the trough fold86. The peak fold80on first surface62corresponds to the trough fold86on second surface64, and the trough fold86on first surface62corresponds to the peak fold80on second surface64. Similarly, the peak fold80on second surface64corresponds to the trough fold86on first surface62, and the trough fold86on second surface64corresponds to the peak fold80on first surface62.

The peak folds80and recess folds86are generally parallel to each other and are generally perpendicular to the rails65. When structure is viewed from the first side, for example as inFIG. 7, the peak folds80extend in a first x-y plane and the recess folds extend in a second x-y plane. The rails65generally span along the x direction, while the orthogonal folds80and86generally span the y direction. The grid-like pattern defined by the rails65and orthogonal folds80may provide an increased surface area for supporting an object on the structure61. Furthermore, the combination of four-ply wall structures82provided generally perpendicular to sloped facets76,78of the folded structure may provide enhanced structural rigidity and stability of the folded structure61which may be advantageous when using said folded structures to support various objects thereon. A substantially similar pattern of peaks80and troughs86, and a similarly repeating pattern of cells63is defined when viewing the structure61from the first side, as inFIG. 7, or the second side, as inFIG. 8. As will be appreciated, the effectively continuous rails65created by the plurality of four-ply walls82and folds80and86provide substantial strength and rigidity to the three dimensional structures61formed using the systems and methods described.

To aid in understanding of the folding methods and apparatus according to the present disclosure, a folding medium60will be described in further detail with reference toFIG. 5, which shows a plan view of an exemplary unfolded sheet of material or folding medium60for use in forming durable support structures according to examples described herein. To form the structure described above, the material60may be folded from a substantially flat, planar state. The medium60herein changes in three directions as it is folded from its planar, unfolded state shown inFIG. 5, into the three-dimensional form shown inFIGS. 7 and 8. Specifically, the medium60increases in height, that is along the z-axis, while decreasing in both length, that is along the y-axis, and in width, that is along the x-axis. The folding medium60may be provided as a generally rectangular sheet of material, or it may have any other desired shape such as circular, oval, trapezoidal, triangular, or other complex profiles as desired or as may be suitable for the particular application. The sheet of material60may include a first longitudinal edge66, a second longitudinal edge67, a first side edge68, and a second side edge69. The first longitudinal edge66and second longitudinal edge67extend between the first68and second69side edges together such edges66-69define the plan profile of the folding medium60.

To facilitate the folding of the sheet of material or folding medium60, a plurality of creases or fold lines70may be formed prior to or while the folding medium60is being folded. In one embodiment, the creases or fold lines70may be formed by scoring or otherwise weakening the foldable medium according to the desired pattern prior to the folding of the medium. For example, perforations, detents, or other features may be imparted along a predetermined pattern on one or both of the surfaces of the folding medium60before the folding process beings. In one embodiment, all of the fold lines70along which the medium will be folded may be pre-defined for example by scoring or perforating the medium60using a laser along a portion or all of such fold lines70. In one embodiment, only some of such fold lines70are be pre-defined before the folding process and other such fold lines70are formed during the folding process. Any combinations of scoring or pre-forming the fold lines may be used as may be suitable for a particular folding material or application. In one embodiment, the unfolded medium60may contain a repeating pattern of scores or creases70which include a plurality of intersecting crease paths71. As the folding medium60is being folded into a three dimensional structure, portions of the medium will displace upward relative to a reference plane of the unfolded medium, that is the x-y plane, while other portions will displace downward relative to the reference plane or remain in the reference plane. That is, the contour of the medium60when formed into a three dimensional structure61will include peaks and troughs defined along the plurality of creases or fold lines70as the respective portions of the medium60fold up and down relative to the plane of the unfolded material.

In broad terms, fold lines70of the folding medium60include a plurality of first crease paths73,75, as examples, extending parallel to each other and a plurality of second crease paths77,79also extending parallel to each other and intersecting the first crease paths73,75. Each first crease path73,75is formed from a plurality of first path segments81. Each plurality of first path segments81associated with each one of the first crease path73,75are generally aligned form a straight line along the x direction. As will be understood, the xyz reference frame referred to herein is used for the purposes of facilitating the description and relative arrangement of components and is not to be taken in a limiting sense.

Each second crease path77,79is formed from a repeating pattern of first and second chevron segments or angled legs83,85and a straight line or leg87extending from a free end88of one of the first and second angled legs83,85, for example the free end88of the second chevron segment85shown inFIG. 5. That is, unlike the plurality of first crease path73,75, which follow a generally straight line, each of the second crease paths77,79follows a path defined by adjoining angled legs83,85and straight lines or legs87. As will be understood, the term “legs” used to describe the imaginary fold lines or scoring pattern of the planar structure described herein is so designated for discussion purposes only and is not to be viewed in a limiting sense. Any similar or suitable designation would be acceptable for the purposes provided.

In one embodiment, the two angled legs or chevron segments83,85may be equal in length and may form an angle of about 120° . That is, a first angle89defined by two adjoining angled legs83,85may in some embodiments be equal to 120 degrees. Other angles may be used to provide different folding patterns or achieve different folded structures. In one embodiment, pairs of adjoining chevron legs or segments83and85have equal lengths, however in some embodiments some pairs may have different lengths. That is, a first pair91of chevron legs or segments may have a first length, while the next or second pair92of chevron legs, which is separated from the first pair91by a straight line segment87joined at one end to first pair91and at its other end to second pair92, may have a second length which is different from the first length. Each of the legs83,85in a pair of angled legs may generally have the same length, for example generally defining a top portion of an equilateral triangle.

A plurality of straight lines or legs87extend between non-adjoining ends of each chevron segments or angled legs83,85. The line87may be of any length. The length of line87may be the same as the length of the angled legs83,85, or it may be a length which is different than the length of such angled legs. Similarly, the first path segments81forming the first crease paths73,75may be of any length as may be desired. The length of the segment81may be the same as any one of the lengths of lines87, or angled legs83,85, or it may be a different length. As will be appreciated in light of the examples described, the length of segment81in combination with the angle of sloping facets76,78may generally define the overall thickness, for example the height in the z axis, of the final folded three-dimensional structure61.

As shown inFIG. 5, the plurality of second crease paths77,79intersect the plurality of first crease paths73,75. The medium60is foldable along the first and second crease paths73,75, and77,79to form three dimensional support structure61according to the present disclosure. One embodiment of the structure61formed from medium60, shown unfolded inFIG. 5, is shown in a partially assembled state inFIG. 6and in a fully folded state inFIGS. 7 and 8.

In one embodiment of the folding process of the present invention, and as shown inFIG. 6for example, during an intermediate folding stage one of the plurality of second crease paths,79for example, is folded upwards, while the next of the plurality of second crease paths in the x direction,79for example, is folded downwards. This is repeated along the length of the side edges68,69to form a pleating or accordion-like structure, as shown inFIG. 6. Due to the discontinuous nature of each of the second crease paths77,79, which as discussed above can be formed by a continuing sequence of first and second angled legs83,85and a straight leg87, the accordion-like pleating does not follow a straight line but instead follows a zigzagging path along the crease paths. This zigzagging of the second crease paths77,79,79, as shown inFIGS. 5 and 6, further facilitates the folding of the medium60into a compact shape. While such a zigzagging pattern has certain advantages, such a configuration is not to be taken in a limiting sense and other configurations or folding patterns can be provided. In one embodiment, the folding medium may be generally rectangular, such that all four sides, for example the longitudinal edges66,67and side edges68,69comprise straight line segments. Creases or fold lines70may be defined on such a generally rectangular medium, without requiring that the medium be cut to any particular shape or have any particular perimeter profile, to provide the desired folding pattern.

Each second crease path77is foldable in an opposite direction from the adjacent second crease path79. This results in the formation of an alternating pattern of ridges or peaks80and valleys or troughs86as the sheet of material or folding medium60is folded. For example, the lowermost second crease path77inFIG. 5can serve as a trough86of the folded structure61, when viewed from the first side such as inFIG. 7, and the adjacent second crease path79can serve as a peak or peak fold80when the structure61is so viewed from the first side. The next adjacent second crease path77in the x direction can serve as a trough86or valley fold86. Each of the first crease paths73,75are straight lines extending between the peaks80and troughs86of adjacent second crease paths77,79, and thus between the first and second longitudinal edges66,67of the folding medium60. Certain adjacent crease paths73,75form a pattern of facets76,78on a surface of the folded structure61. At least some of the first crease paths73,75, and in one embodiment all of the crease paths73,75,follow a zigzagging pattern or sequential ascending and descending lines to form a plurality of alternating ascending and descending paths90that extend between first and second longitudinal edges66,67and define the ascending and descending facets76,78of the folded structure. A first plurality of adjacent first crease paths93,94, included in paths90, connect the respective opposite ends of adjacent straight lines87and follow the ascending and descending contour of adjacent cells63. Each facet76,76is bounded by a portion of adjacent first crease paths93,94and a pair of adjacent peak folds80and valley folds86. A second plurality of the first crease paths95,96, included in paths90, respectively connect the adjoined ends of a first pair of adjacent angled legs83,85and the adjoined ends of a second pair of adjacent angled legs83,85, and each respectively fold into and become part of a pair of adjacent rail or wall65of the support structure61.

In one embodiment, and as depicted inFIGS. 7 and 8, each portion108of rails63spanning between adjacent cells63of the folded structure may include at least a pair of two-ply segments97, which form the end walls72,74and thus the at least four-ply wall structure82between such adjacent cells63. In one embodiment, each of the two-ply segments97may extend into the adjacent portion108of the rail65, that is the portion108between the adjacent cells along the x axis, and thus sections of the rail65may comprise8-ply structure. Other configurations may be achieved using different crease paths, for example varying the length of the first path segments81, chevron segments83,85and straight line or leg segment87, as well as varying the angles between such segments, for example the angle89between adjoined chevron or angled leg segments83,85. In one embodiment, when the length of angled segments83,85is greater than the length of line segment87, the resulting rail65may include portions which have more than four plies. In one embodiment, some portions of the rail65may have fewer than four plies, for example two plies.

The folding process will be further described with reference to one of a plurality of regions98of the tessellated folding medium60, illustrated inFIG. 6and depicted in greater detail during stages of the folding process inFIGS. 9 and 10. As shown in a partially folded state inFIGS. 6 and 9, in one embodiment a portion of the folding medium60comprises a first leg or chevron segment83and a second leg or chevron segment85forming a first angled segment or chevron. The first leg83and second leg85are preferably of equivalent length. A first angle89exists between the first leg83and the second leg85. The angle89preferably measures about 120° in the flat unfolded state. A third leg or straight line87extends from a free end88of the second leg85and another third leg87extends from a free end of the first leg83. The length of third legs87may be of any length to accommodate manufacturing preferences, thus the third leg may be equal to, shorter or longer than the first and second legs83,85. The third leg87adjoining first chevron segment83extends at a second angle99from the first chevron segment83and the third leg87adjoining second chevron segment85extends at a third angle100from the second chevron segment85. Each of the angles99,100which may be approximately 150° in the flat unfolded state of the folding medium, illustrated for example inFIG. 5. In one embodiment, the angles89,99and100may be different in size. In one embodiment, some or all of angles88,99and100may be the same in size.

A set of first segment or leg83, second segment or leg85and one of the adjoining third segments or legs87, for example the leg87adjoining first segment83, define a repeating pattern109along the length of the first crease paths77,79, and thus the length of folded structure91(seeFIGS. 6,9and10). Each such repeating pattern109is connected by a plurality of first path segments81to an adjacent pattern109of adjoined legs87,83,85, spaced apart along the x axis by such plurality of parallel first path segments81, to define a repeating pattern of facets101,102, and103that extend along the length of folded structure61. A fourth angle111is defined by the intersection of each first path segment81and the free end88of each first chevron segment83, and a similar fourth angle111is defined by the intersection of each first path segment81and the free end88of each second chevron segment85(seeFIG. 5). In one embodiment, the fourth angle111may be approximately 60 degrees in the flat unfolded state of the folding medium, illustrated for example inFIG. 5. In one embodiment, for example depending on the size of angles89,99, and100, the fourth angle111may be other than 60 degrees. A fifth angle113is defined by the intersection of the straight horizontal line segment87and the adjoining vertical line segment81, and may be approximately 90 degrees, as illustrated inFIG. 5. Angle113generally remains at 90 degrees when the structure61is fully folded, as illustrated with region98shown inFIG. 10. As the medium60is folded the angles99and100which may originally be obtuse angles may collapse or reduce to approximately 90 degrees, and angle89between adjoining angled legs83,85which may originally be obtuse an obtuse angle may collapse or reduce to zero, in the fully folded structure61having the grid-like pattern or tessellation of cells63.

In this manner, the repeating pattern of facets101,102and103, defined by various combinations of legs or segments87,83and85as described above connected by a plurality of first path segments81, repeat along both the y-axis and the x-axis (seeFIGS. 5-6). Any number of repeating pattern of facets101,102and103may be used to form the three-dimensional support structures herein. Preferably, the size of the three-dimensional support structure is defined by the number of facets101,102and103, the size of such facets, or the legs87,83and85creating the facets, and the desired size of the support structure to be created by the folded tessellated medium. Adjacent pairs of the repeating pattern109of legs87,83and85interconnected by a plurality of first path segments81spaced apart along the y axis define a repeating pattern of longitudinal regions or strips110,112of the folding medium60which extend along both the length and width of the medium60. When the medium60is folded, one or first region or strip110slopes upwards as it extending in the x direction and the adjacent second region or strip112slopes downwards as it extends in the x direction, as shown inFIG. 10, so as to provide a pleated or accordion-like portion of one embodiment of the folded support structure of the present invention.

As described herein, the scores or fold lines that can be preformed in the medium60for forming the legs or segments of the foldable medium, for example legs or segments87,83,85,81, serve to assist in folding the medium60into the support structure of the present invention. The fold lines depicted herein, for example inFIGS. 5 and 6, are provided for illustration purposes, and it is understood that in some embodiments no such preformed scores fold lines are present on the sheet of material. In this regard, folds can be formed during the folding process along at least some of the imaginary fold lines described above, for example along some or all of legs or segments87,83,85,81. As the medium60is folded, for example as shown inFIG. 6, the scores or fold lines cooperate to form a series of peaks80and valleys86in the medium60ultimately resulting in the repeating pattern of cells63described herein. In one embodiment, where scoring or other weakling of the material or foldable medium60) is provided prior to the folding process, the scoring may be provided on one or both of the surfaces of the foldable medium60. For example, scoring may be provided only on a top surface of the medium for a select set of the plurality of crease or fold lines70, and scoring may be provided on the bottom surface of the medium for the remaining crease or fold lines70. As will be appreciated, providing scoring selectively on the top or bottom surface of the material may guide the direction of folding, in that the medium may naturally fold in the direction of the weakened surface.

In one embodiment of the folding process of the invention, the foldable medium60may be folded in the desired pattern of cells63as follows. A pleating of the medium may be obtained by folding consecutive or adjacent second crease paths77,79in alternating upward and downward directions. Simultaneously or at a different time, which may be prior to or after the pleating step, the medium may also be folded along first crease paths73,75. As the folding medium is folded, the angle89decreases in size until it becomes approximately zero degrees, at which point, a first endwall72of one cell abuts or lies adjacent to a second endwall74of the adjacent cell forming the four ply structure82. The angles99defined by each straight line segment87and the adjoining angled leg83and the angles100defined by each such straight line segment87and the adjoining angled leg85both also decrease as the structure is folded, and in one embodiment of the structure61illustrated inFIGS. 7-8is approximately 90 degrees. In the folded configuration, each of the segments87coincides with a peak fold80or valley fold86. Accordingly, in the folded configuration, the resulting angles107between the segment87and each of the adjoining segments83and85, which define the edges of the four ply wall structure82, is approximately 90 degrees. In this manner, a repeating pattern of cells63is formed and may be arranged in a generally grid like or tessellated manner. As will be appreciated, the resulting folded structure has overall dimensions, for example length and width, which are less than the dimensions of the flattened unfolded medium. That is, as the three-dimensional structure is formed from a single sheet of material, the dimensions of the resulting product decrease along the x and y direction, while the dimension of the resulting product increases in the z direction, thus adding height to the structure.

Returning now to the exemplary apparatus and methods for forming the folded structures of the present invention, the relative positioning, actuation and operation of the top and bottom arrays10,12of creasing elements13,14will now be described. In the exemplary apparatus1, each array10,12includes a plurality of respective creasing elements13,14arranged in respective columns31,33and respective rows32,34and configured to be moveable along the x direction and the y direction. In addition, one or both of arrays10,12may also be moveable in the z or vertical direction15. Relative motion of the arrays10,12and of the individual respective creasing elements13,14will be further described below with reference to an exemplary folding operation.

FIG. 14shows a perspective view of a portion12aof the second or bottom array12, depicted inFIGS. 1-4, in a fully expanded or first position. A corresponding top portion10aof the first or top array10, in a fully expanded or first position, is shown along with the bottom portion12ainFIGS. 16-17,19-20. For clarity of illustration and simplification, only portions10a,12aof the arrays10and12are shown inFIGS. 14-17,19-21,23-24and28-30, however the exemplary arrangements depicted and described herein may apply to any size array according to the present disclosure, for example the full arrays10,12shown inFIG. 1, or to arrays of any other size or arrangement selected as may be desired.

It is appreciated that some or all of creasing elements13of top array10can be substantially identical, and that some or all of creasing elements14of bottom array12can be substantially identical. In one embodiment, illustrated in the above figures, all of creasing elements13,14are identical. Each individual creasing element13,14, which may also be referred to as a creasing member or a folding element or member, may be implemented as a generally elongate member, which may have a rectangular transverse cross section (seeFIGS. 14-15). It is appreciated that some or all of the creasing elements may be configured to have substantially any transverse cross section, for example such creasing elements may be circular or oval in the transverse cross-section such that the creasing elements are generally shaped as rods or other cylindrical members. Other form factors may be used as desired for forming some or all of the creasing elements.

In one embodiment, each creasing element13,14includes a first or top portion150and a second or body portion151(seeFIG. 14with respect to bottom array portion12a). The top portion150may be shaped to have a leading edge122which is configured to engage or fold the foldable medium60. The leading edge122may be shaped in any manner suitable to engage the sheet of material or folding medium60and facilitate the folding of the sheet of material. For example, the leading edge122may include a sharp or dull edge disposed at the top most end of the top portion150. The leading edge may be continuous or segmented with one or more spaces therein so as be noncontinuous. The leading edge122may be provided with sharp puncture or scoring elements spaced along the edge for scoring the medium60along a fold line70or otherwise facilitating folding of the medium at the portion engaged by the leading edge. The leading edge122may be defined by two opposite sloping sides or faces124,126of the top portion150inclined at any suitable angle relative to each other and sloping outwardly from and relative to leading edge122to accomplish the desired folding of the medium. In one embodiment the sloped sides124,126are inclined at an angle of not greater than 90 degrees relative to each other, and in one embodiment the sloped sides124,126are inclined at an acute angle, for example 60, 45 or 30 degrees, relative to each other. The leading edge122may be slightly rounded so as to prevent or minimize risk of tearing or otherwise damaging the material or medium60being folded. The sides or faces128,130extending between the sloping sides124,126may be generally parallel to each other, or they may be angled relative to one another, and in one embodiment extend at 90 degrees to the sides or faces128,130. As shown inFIG. 14for example, the top portion150of an exemplary creasing element14is shaped to resemble a gable in that it has a generally triangular cross section in the x-z plane formed by sloping faces124,126that are inclined relative to each other.

Body portion151of a creasing element can include a top, distal or upper section170, a middle or central section171and a bottom, proximal or lower section172, as shown inFIG. 14. The body portion151of each creasing element13,14may be shaped and configured in any manner desired which accommodates coupling the body portion151of each creasing element of the respective array10,12and which further accommodates coupling the array to the actuation assembly5. In one embodiment, as discussed above, the creasing elements of each array are arranged in rows and columns such that each creasing element is adjacent to at least one and preferably a plurality of other creasing elements. For example inFIG. 14with respect to bottom array12, creasing element14eis adjacent to and disposed between creasing elements14d,14falong the x direction and adjacent to and disposed between creasing elements14b,14hin the y direction.

Adjacent creasing elements can be connected together using suitable linking assemblies which can permit expansion and contraction of columns of creasing elements along the y axis and expansion and contraction of rows of creasing elements along the x axis. In one embodiment, the expansion and contraction of the creasing elements in the y axis is independent of the expansion and contraction of the creasing elements in the x axis. The linking assemblies may be configured such that all creasing elements in a row33or34of creasing elements are moveable together in a first direction, for example along the y axis, and all creasing elements in a column31or32of creasing elements are moveable together in a second direction, for example along the x axis. As such, the first direction and second direction can be orthogonal to each other. In one embodiment (not shown) of creasing element arrays substantially similar to arrays10,12, the linking assemblies may be implemented using x-guide rods and y-guide rods, where x-guide rods couple rows34of creasing elements together and y-guide rods couple columns32of creasing elements together, in each case to permit expansion and contraction of such creasing elements relative to each other. For example, a first x-guide rod may couple the creasing elements of a first row together such that the first row of creasing elements moves in unison in a first direction. A second x-guide rod may couple a second or adjacent row of creasing elements such that the all creasing elements in the second row move in unison in the first direction. In an exemplary orthogonal orientation in which the second direction is perpendicular to the first direction, a first y-guide rod may couple all of the creasing elements in a first column31or32together, and a second y-guide rod may couple all of the creasing elements in a second column31or32together. The y-guide rods may be disposed generally perpendicularly to the x-guide rods an as such create a matrix of rod elements when viewed in plan, that is in the x-y plane. Individual creasing elements may be provided at imaginary intersection points of the two rod elements. The x-and y-guide rods may be coupled to individual creasing elements such that each individual creasing element is able to move both in the x and y directions. For example, the x-guide rods may be provided in a first x-y plane, while the y-guide rods may be provided in a second x-y plane offset from the first x-y plane along the z axis. The plurality of parallel x-guide rods may be so offset along the z direction above or below the plurality of parallel y-guide rods such that the movement of the x-guide rods along the x direction does not interfere with the movement of the y-guide rods along the y direction.

In one embodiment, the linking assemblies, which may interchangeably be referred to herein as expandable linking assemblies or directionally expandable linking assemblies, may be implemented using y-travel scissor assemblies154and x-travel scissor assemblies152for respectively coupling together columns31or32of creasing elements and rows33or34of creasing elements. Each y-travel154and x-travel152scissor assembly, which can be made from any suitable material such as metal or plastic, includes a pair of scissor elements or links. For example, each y-travel scissor assembly154may include a first y-scissor link156and a second y-scissor link158(seeFIG. 14). The first and second y-scissor links156,158are pivotaly coupled together using a pivot means or joint that can include for example an x-center pivot element or pin157. Each y-scissor link156,158has a y-first end160and a y-second end162. In one embodiment, the y-first end160of each y-scissor link156,158may be fixedly coupled to central section171of the body portion151of respective adjacent creasing element, for example by using a y-fixed pivot element or pin161. In one embodiment, the y-first end160of first y-scissor link156is coupled to one side of its creasing element and the y-first end160of second y-scissor link158is coupled to the opposite other side of its creasing element. The y-second end162of each y-scissor link156,158may be slidably coupled to central section171of the body portion151of the respective adjacent creasing element, for example using a y-moveable pin163slidably disposed in a y-slot165provided on the central section171and extending longitudinally in the z direction. In one embodiment, the slidable end162of each scissor link156,158is below the pin161on the central section171but on the same side of the creasing element as the respective y-first end160of the link, however an alternate arrangement can be provided in which the slidable end162is provided above the fixed end160. In one embodiment, the y-first end160of each y-scissor link156,158may be slidably coupled to the respective adjacent creasing element13,14, and the y-second end162may be fixedly coupled to the respective adjacent creasing element. Furthermore, in the present example a single y-travel scissor assembly154is provided for coupling together each pair of adjacent creasing elements, however in one embodiment more than one, for example, two, three or more y-travel scissor assemblies may be included and similarly configured. Each y-scissor link156,158is longitudinally sized to permit the desired separation between adjacent creasing elements coupled together by such links during expansion of the respective array10,12in the y direction.

In a similar manner, each x-travel scissor assembly152may include a first x-scissor link153and a second x-scissor link155(seeFIG. 19). Similar to the y-travel scissor links156,158, each x-travel scissor link153,155has a x-first end164and a x-second end166. In one embodiment, the x-first end164may be coupled to the body portion151using a x-fixed pin167. In one embodiment, the x-first end164of first x-scissor link153is coupled to one side of its creasing element and the x-first end164of second y-scissor link155is coupled to the opposite other side of its creasing element. The x-second end166of the x-scissor links may be moveably or slidably coupled to the body portion151using a x-moveable pin169extending through a x-slot168provided in the body portion151and extending longitudinally in the z direction on the body portion151. The x-second end166of each link153,155is slidable coupled to the respective body portion151on the same side of the creasing element as the respective x-first end164of the link. The first x-scissor link153and second x-scissor link155may be pivotally coupled to each other using a x-center pin159. Each x-scissor link153,155is longitudinally sized to permit the desired separation between adjacent creasing elements coupled together by such links during expansion of the respective array10,12in the x direction. In one embodiment, the y-scissor links156,158are longer than the x-scissor links153,155to permit greater expansion of the arrays10,12in the y direction than in the x direction. In the present example, first and second x-travel scissor assemblies are utilized for coupling together each adjacent pair of creasing elements in the x-z plane. First x-travel assembly152ais coupled to distal or upper section170of each adjacent creasing element, above y-travel scissor assemblies154, and second x-travel assembly152bis coupled to proximal or lower section172of each adjacent creasing element, below y-travel scissor assemblies154. It is appreciated that any number of x-travel scissor assemblies may be provided. In one embodiment, a single-travel scissor assembly may be used for coupling together each pair of adjacent creasing elements. Further, it is appreciated that any arrangement of the scissor assemblies152,154on the creasing elements, different from the arrangements discussed above, can be provided.

The pivotal joints159in combination with the moveable or slidable coupling between at least one end166of the x-scissor links153,155and a respective portion of the adjacent creasing elements13,14allow the relative angle180between such scissor elements or links153,155to change (seeFIG. 19). The change in angle180causes the distance183along the x-axis between adjacent creasing elements13,14to decrease or increase. Similarly, the pivotal joints157in combination with the moveable or slidable coupling between at least one end162of the y-scissor links156,158and a respective portion of the adjacent creasing elements13,14allow the relative angle181between such scissor elements or links156,158to change (seeFIG. 20). The change in angle181causes the distance182along the y-axis between adjacent creasing elements13,14to decrease or increase. In this manner, the linking assemblies, for example scissor assemblies152,154facilitate expansion and collapsing or contraction of the arrays10,12of creasing elements during the folding process.

The creasing elements13,14can be made from any suitable material such as metal, plastic or a ceramic material, and in one embodiment can be made from a rigid such material. Not all of the creasing elements need be made from the same material, for example some creasing elements can be made from a rigid plastic, some other creasing elements can be made from metal and some other creasing elements can be made from a ceramic material. In one embodiment, the top150and body151portions of each creasing element13,14may be formed as a single unitary structure, for example a monolithic component fabricated in one piece by molding or machining, as examples. In one embodiment, each creasing element may comprise a plurality of individual sub-components which are assembled to form the creasing element and assembled into each of the arrays10,12of creasing elements.

In one embodiment, an end portion173of the bottom section172of a creasing element13,14may be provided with a sliding contact surface or bearing175. In one embodiment, the end portions173may be sufficiently spaced apart from and above the platforms4,6such that the end portions173do not contact the platform at any time or during operation of the actuation or creasing assemblies5,7. In such an embodiment, the arrays of creasing elements may be generally described as floating above the platforms4and6. Additional rigidity and force may be obtained by allowing the imaginary bottom surfaces of each array10,12to contact the respective platforms6,4. In this regard, the end portion173of each creasing element13,14may be lubricated and/or coated with a slip agent, or other low frictional material, for example a polymer. The end portion173may be fabricated using a material having a low coefficient of friction, or the end portion173may be otherwise configured for sliding and/or bearing contact with the platforms, for example by using roller bearings or other conventional low frictional bearing mechanisms. Various sliding or pivoting joints, such as the pivotal joints157,159, fixed pins161,167and sliding pins163,169as well as surface of sliding contacts, for example surfaces of slots165,168adapted for receiving the sliding pins163and169, may also be lubricated, coated with or otherwise manufactured from materials which provide low frictional resistance and minimize wear of such sliding components.

The specific embodiments of linking assemblies or expandable linking assemblies described above, including rod elements and scissor assemblies152,154, are just two examples of the various implementations of interlinking of creasing elements that are possible according to the present disclosure. It is appreciated that other variations are possible which accomplish the desired linking of creasing elements such that all creasing elements in a given row33,34of creasing elements may be moveable in unison in a first direction, and all creasing elements in a given column31,32of creasing elements may be moveable in unison in a second direction. In one embodiment, individual actuation of each creasing element13,14may also be provided if desired, and one or more controllers may be configured to create the coordinated movement of creasing elements13,14. For example, using a desired timing sequence, the plurality of push/pull bars51-54working in conjunction with the compliant linking assemblies, for example x-travel scissor assemblies152and y-travel scissor assemblies154, may operate to cause the arrays10,12to collapse or contract along the x and y directions thereby forming folded structures61according to the present invention (seeFIGS. 12,25-27).

An exemplary folding operation will now be further described with reference toFIGS. 16-31to further illustrate the methods and apparatus of the present invention. Although some of such figures include only portions10a,12aof top and bottom arrays10,12, the discussion herein is applicable to the entire arrays10,12and thus will reference the entire arrays10,12illustrated inFIG. 1and other figures herein. Initially, a sheet of material115, which may be configured as folding medium60and have a similar pattern of imaginary fold or crease lines as described above, may be placed between first or top leading edges120of the first or top creasing elements13of the first array10and second or bottom leading edges122of the second or bottom creasing elements14of the second array12, as shown inFIG. 17.

In one embodiment, the first array10and the second array12are initially in a first relative position in which the respective individual creasing elements13,14are not interdigitated with each other. Instead, the plane defined by the leading edges120of the creasing elements13of the first array10is generally in the same plane or spaced away from the plane defined by the leading edges122of the creasing elements14of the second array12(seeFIGS. 16 and 17). In one embodiment, the first array10and the second array12may be spaced apart from each other and the sheet of material115may be inserted or placed on the leading edges122of the creasing elements14of the bottom array12, and subsequently the first or top array10may be actuated downwardly to cause the leading edges120of the creasing elements13of the first or top array10to contact surface of the sheet of material115(seeFIGS. 17,19, and20).

As the folding operation proceeds, the top array10is actuated further downwardly along the z direction, for example by actuation assembly25, moving the leading edges120of the creasing elements13of the top array10below the plane defined by the leading edges122of the creasing elements14of the bottom array12. In this manner, the first array10and second array12of creasing elements13,14are moved to a second position relative to each other where the creasing elements13of the first array10are at least partially interdigitated with the creasing elements14of the second array12(seeFIGS. 21,23, and24).

During downward motion of the top array10to its second or partially interdigitated position, individual creasing elements13of the top array10may be brought closer together along the x direction, for example by use of first and second top x actuators18a,18cand first and second top x rack and pinion assemblies42a,42c, thereby collapsing the top array10along the x direction. In this regard, actuators18a,18ccan serve to rotate the gearing mechanisms or rack and pinion assemblies42a,42cto decrease the distance between top x push/pull bars51,52thereby contracting the top array10in the x direction. In a similar manner, individual creasing elements14of the bottom array12may be brought closer together along the x direction, for example by use of bottom x actuators20a,20cand first and second bottom x rack and pinion assemblies45a,45c, thereby collapsing the bottom array12along the x direction. In this regard, actuators20a,20ccan serve to rotate the gearing mechanisms or rack and pinion assemblies45a,45cto decrease the distance between bottom x push/pull bars51,52thereby contracting the bottom array10in the x direction.

The x push/pull bars51,52, which may be rigidly or otherwise coupled to the sides of the arrays10,12, for example using the y-guides57,58, may be translated along the x direction to cause the collapsing and contracting of the arrays10,12. An inward or compressive force is thus applied by one or more of the x push/pull bars51,52to the sides of the arrays10,12which span the y direction. The force is generally applied to the end row of creasing elements and transmitted, for example via rigid body motion of the end row of creasing elements, to each of the end x-travel scissor assemblies152and thus to each other creasing element in such row. The rigid body motion of each of the end creasing elements may force the unconstrained portion of the scissor assemblies152, for example the pivotally mounted ends166, to translate within the slots168moving the pivotally mounted ends166downward, in the case of the bottom set of x-travel scissor assemblies, and upward, in the case of the top set of x-travel scissor assemblies (seeFIG. 19). The pivotally mounted ends166are coupled to adjacent ones of the pivotally mounted ends166and as such they move in unison under the compressive force of the x push/pull bars51,52. Since the creasing elements in each row are coupled by the y-travel scissor assemblies154to adjacent creasing elements in the next or adjacent row, movement of certain rows of creasing elements by the x push/pull bars51,52cause similar movement in the x direction of all of the creasing elements in the array.

In an analogous manner, a compressive or inward force may be exerted by the y push/pull bars53,54which is applied to the end columns and certain of the internal or central columns of creasing elements via the x-guides55,56mounted to such bars53,54and connected to such columns of creasing elements. The inward motion of such columns of creasing elements of the top and bottom arrays10,12causes the y-travel scissor assemblies154of such columns to fold or collapse and the pivotally mounted ends162to move within slot165in a downward direction, in the case of the bottom array12, or an upward direction, in the case of the top array10. Pins163couple each of the pivotally mounted ends162to each other causing them to slide up and down in unison. Since the creasing elements in each column are coupled by the x-travel scissor assemblies152to adjacent creasing elements in the next or adjacent column, movement of certain columns of creasing elements by the y push/pull bars53,54cause similar movement in the y direction of all of the creasing elements in the array.

In one embodiment, the contraction of the top array10and top array12are coordinated and thus occur simultaneously such that the top array10and bottom array12contract in unison in the x direction. The downward motion along the z direction and contracting motion along the x direction of the arrays10,12may be coordinated such that the relative distance185between the leading edges120of the creasing elements13of the top array10and the leading edges122of the creasing elements14of the bottom array12remains generally constant (seeFIG. 19). In this manner, tearing or other damage to the sheet of material115may be prevented. In some examples, the coordination of relative movement of the arrays10,12may be adjusted such that the relative distance185is allowed to vary thereby imparting a stretching force to the sheet of material115, which sheet in some examples may be made of a compliant material. For example, and with reference toFIG. 19, the leading edges122of bottom creasing elements14contact the sheet of material115along a first plurality of straight line segments87along the y axis. The leading edges120of top creasing elements13contact the sheet of material115along a second plurality of straight line segments87along the y axis. In one embodiment, the straight line segment87contacted or engaged by a creasing element13in a row of top array10is adjacent the straight line segment87contacted or engaged by the adjacent creasing element14of the bottom array12in a corresponding row. The portion of the material115which includes the chevron or angled legs83,85of the crease paths is not engaged by any surface or edge of the creasing elements at this stage. That portion remains unsupported by the creasing elements and disposed between adjacent columns of creasing elements. As the top and bottom arrays10,12become partially interdigitated, the first plurality of straight line segments engaged by the top array10moves downwardly, while the second plurality of straight line segments engaged by the bottom12moves upwardly to form the accordion-like pattern of troughs or valleys86and peaks or folds80described previously with reference toFIGS. 5-10. The material spanning the chevrons or angled legs83,85also folds in a similar manner by virtue of being connected to the straight line segments87, which are in engagement with the plurality of creasing elements13,14. The folding of the unsupported material causes first spaced apart endwalls72and second spaced apart endwalls74to begin taking shape by bringing the two plies of each wall closer together.

In a next stage of the folding operation, the top array10and bottom array12of creasing elements13,14are contracted in the y direction, which as described above may be accomplished by bringing the y-push/pull bars53,54closer together. During this stage, the material extending unsupported between the columns of creasing elements, for example the portion of the medium60spanning the chevrons or angled legs83,85that is to become the spaced apart endwalls72,74, may be forced to fold in a forward or a backward direction, as may be desired. As previously described, selectively perforating or scoring the medium60or115along only one side of the medium may dictate the direction of the fold. By providing certain crease paths, for example the crease paths75, only along one face of the foldable medium60or115, the facets102,103(seeFIG. 9) defined by the chevrons or angled legs83,85may be forced to fold in a forward direction relative to the faces101, as shown for example inFIG. 21. Each endwall72may be formed a pair of adjacent facets102and each endwall74may be formed from the pair of adjacent facets103, each with respect to the x axis and as shown for example inFIG. 9. In this step, and as the columns of creasing elements move closer together, adjacent pairs of endwalls72,74are further collapsed to form the four ply wall structures82.

The top array10and bottom array12may move through several intermediate positions of interdigitations during the folding operation. Furthermore, in certain embodiments, contraction of the arrays10,12in the y direction may occur simultaneously with or separately from contraction of the arrays10,12along the x direction, and contraction or interdigitation of the arrays10,12in the z direction15may occur simultaneously with or separately from contraction of the arrays in one or both of the x and y directions. For example, the arrays may be moved from the noninterdigitated position, for example where the top array10and bottom array12are farthest apart, to the fully interdigitated position, for example where the creasing elements13,14are closest together along the x direction, before or while contracting of the arrays occurs along the y direction.

As the arrays10,12move from a partially interdigitated or second position to a fully interdigitated or third position, the x-travel scissor assemblies may become fully collapsed, and as the arrays10and12are fully contracted along the y direction, the y-travel scissor assemblies may also become fully collapsed to form the compact configuration shown inFIGS. 25-30. At this point, the medium60or115is folded to its final folded configuration, for example as depicted inFIG. 31and as also depicted and described in reference toFIGS. 7 and 8. In this fully collapsed position, each two abutting endwalls72,74may become sandwiched or compressed by the sides128,130of the top portion of adjacent creasing elements, particularly for example where the length of the leading edges120,122of the elements is substantially equal to the straight line segments87of the medium, and both sides of each of the adjacent sloped sidewalls or facets7678of a cell63may come in full contact with the sloping sides faces124,126of the respective creasing element. In other words, the interdigitation of the top portions150of the creasing elements13,14and the contraction along the y axis of the arrays10,12of creasing elements operates to fold the medium60or115into a three-dimensional structure61, for example as shown inFIGS. 7-8and31.

After the three-dimensional structure61has been formed, one or both of the arrays10,12may be actuated along the z axis or direction15away from each other to allow for the formed structure to be retrieved from the apparatus1. For example, the top array10may be actuated using the linear actuator8along the z axis or vertical direction15. The folded three-dimensional structure61may be removed from the bottom array12and may then be available for use or further processing. Each of the top array10and bottom array12may then be expanded to their respective first, starting or home position, with the expansion of each of the top and bottom arrays10,12occurring simultaneously or in sequence. For example, array10may be expanded along the x direction by moving the x-push/pull bars51,52from the contracted position shown inFIG. 25to the farthest apart position shown inFIGS. 4 and 12by rotating the pinion gears17,34of the rack and pinion assemblies45a,45cin a clockwise direction. The pairs of rack gears19,21and39,41may translate along the x direction ends of the outer ends of the rack gears moving farther apart and thereby causing the x-push/pull bars to move farther apart. As previously described, each of the x-push/pull bars may be coupled, rigidly or otherwise, to the end rows of the arrays10,12, and the outward movement of the x-push/pull bars causes the end row of creasing elements to move outwardly. As during the contraction of the array, by virtue of interconnecting each creasing element or folding element to the next or adjacent creasing element or folding element using x-travel scissor assemblies152, the pulling motion or force applied to the end rows of the creasing elements is transmitted towards the interior of the array causing all interior x-travel scissor assemblies152to expand.

The array10may be expanded along the y direction in an analogous manner by moving the y-push/pull bars53,54from the contracted position ofFIG. 25to the expanded or home position ofFIGS. 4 and 12. Rotation of the pinion gears27and47in the clockwise direction causes the pairs of rack gears46,48and26,28to move along the y direction such that outer ends of the rack gears move apart from each other thereby causing the y-push/pull bars53,54, which are coupled to the ends of the racks, to move outwardly relative to each other. The expansion of the y-push/pull bars53,54applies a pulling force along the top and bottom end columns of creasing elements, for example by means of x-guides55,56. The pulling force along the end columns is transmitted to the interior of the array causing all of the y-travel scissor assemblies154to expand.

In the present example, four x-guides55are used at the front side of the arrays and four x-guides56are used at the back or rear side of the arrays, however any other number of x-guides may be used. Similarly, two y-guides57and two y-guides58are used to couple the left and right sides of each array to the respective push/pull bars of the portion of apparatus1, however any other number, for example four, eight or more, of guides may be used along each side. As will be appreciated, the x-travel scissor assemblies152allow the arrays10,12to collapse or contract or expand when an appropriate force is applied along the x direction. When a force is instead applied along the y direction, the x-travel scissor elements act as a generally rigid link connecting each of the creasing elements of a column of creasing elements forming a generally rigid column or beam. Similarly, the y-travel scissor assemblies154allow contraction or expansion along the y direction but form a generally rigid coupling along rows of creasing elements. In this manner, a pulling force applied perpendicular at one or more points along the generally rigid column of creasing elements may be sufficient to cause all of the creasing elements in the column to move in reaction to that force. Similarly, a pulling force applied perpendicular to the rigid row assemblies formed by interconnected creasing elements and y-travel scissor assemblies may be sufficient to cause the rows of elements to move along the pulling force. In this regard, the combination of orthogonally arranged x-travel and y-travel scissor assemblies152,154not only allows for collapsing of the arrays but also advantageously forms generally rigid rows and columns of creasing elements allowing for the expansion of the arrays.

In one embodiment, the angle by the inclined faces124,126forming the leading edge120,122of a creasing element is not greater than, or substantially equal to or less than, the angle between the sloped side walls or facets76,78of the desired cell63to be formed by the creasing element. In one embodiment, apparatus1is constructed so that the angle between the inclined faces124,126of the creasing elements13,14is less than or equal to the smallest desired angle between the sloped side walls or facets76,78of the cells63in the folded structure61intended to be created by such creasing elements13,14.

The depth of the cells63in the folded structure61created by apparatus is determined by the amount of full interdigitation of the creasing elements13,14forming such cells63, that is the distance along the z axis that the leading edge120of the respective creasing elements13extend between and beyond the leading edge122of the respective creasing elements14forming the cell. In one embodiment, the amount or distance of full interdigitation between a creasing element13of top array10and adjacent creasing elements14of bottom array12permitted by apparatus1is not less than the maximum distance along the z axis that valley fold86of the desired cell63to be created extends below the opposed end walls72,74of such cell63.

Each cell63of the folded structure61has a width along the x axis and a length along the y axis. The width of a cell63, which is generally the distance between adjacent peak folds80is determined by the amount or distance along the x axis to which the leading edges120,122of adjacent creasing elements of the first and second arrays10,12contract to in the final or contracted position. The length of a cell63, which is generally the length of the straight line segment87, is defined by the cumulative length of opposing leading edges120,122of opposing creasing elements. That is, in some examples, the top and bottom arrays may be offset along the y direction to vary the length of each resulting cell. The configuration and operation of an apparatus according to the present invention to achieve offsetting of the arrays along the y direction, for example, will be further described with reference toFIGS. 32 and 33below.

Further variations of the resulting cells63may be achieved. For example, if the leading edge122of the opposed creasing element in the second array of the apparatus1forming such cell is located between such creasing elements of the first array an equal distance from each such creasing element of the first array, then valley fold86of the cell will be located in the middle of the cell. Alternatively, if the leading edge122of the opposed creasing element of the second array is spaced closer to the leading edge122of one of the adjacent creasing elements of the first array, then the valley fold86of the cell will likewise be closer to one of the peak folds80of the cell. In one embodiment, the amount or distance along the x axis of the leading edge122of adjacent creasing elements of the first array10,12permitted by apparatus1is not less than the maximum distance along the x axis that of the peak folds80of the desired cell63to be created by the apparatus.

As can be appreciated from the foregoing, apparatus1permits folded structures61to be created having cells63therein of various shapes and sizes.

As previously discussed, an apparatus of the invention call also be provided that permits the length of a cell63of the formed folded structure61to be varied from structure to structure, which may be achieved without changing the size of the creasing elements or otherwise reconfiguring the top and/or bottom arrays10,12. As such, opposed creasing elements having respective leading edges120,122of fixed lengths can be utilized with a foldable medium60having an imaginary straight line segment87of a first length defined thereon, so as to form a first cell63having a distance or length between opposed end walls72,74of such first length. In addition, such opposed creasing elements can be utilized with a foldable medium60having another imaginary straight line segment87of a second length defined thereon, that is different from the first length, such that a second cell63having a distance between opposed end walls72,74of such second length may be formed. One embodiment of such an apparatus is illustrated inFIG. 32, which for simplicity and clarity shows a partial isometric view of the apparatus. In the example shown inFIG. 32, certain components of the actuating assemblies and support assemblies are shown, while certain other portions of the apparatus, for example the top and bottom arrays10,12, are omitted so as not to obscure the disclosure of the present example. The arrays10,12(not shown inFIG. 32) may be essentially the same as previously described with reference to apparatus1, and it will be understood that any combinations of creasing elements and arrays of creasing elements may be used in the example ofFIG. 32.

Apparatus201illustrated inFIG. 32is substantially similar to apparatus1and like reference numerals have been utilized to describe and identify like components of apparatus1and201. Apparatus201permits relative movement along at least one of x and y axes between the creasing elements13of top array10and the creasing elements14of the bottom array12(not shown inFIG. 32). In one embodiment, creasing elements13of the top array are movable in unison in a direction along the y axis relative to the creasing elements14of the bottom array. Although such movement can be of any suitable distance, in one embodiment such distance ranges from 0.125 to 1.0 inch, in one embodiment from 0.125 to 0.5 inch and in one embodiment is approximately 0.25 inch.

In one embodiment, an additional moveable plate202is included in apparatus201. Translation plate202, also known as y-translation plate202, is slidably secured to the bottom of moveable plate6by any suitable slide assembly203. In one embodiment, the slide assembly includes at least first and second grooves206a,206bformed in the bottom of plate6in spaced-apart positions along the x axis. Translation plate202is provided with at least first and second slide elements207a,207bfor cooperating with respective grooves206to permit plate208to move in the y direction relative to plate6. The slide elements207can be in the form of first and second rails207a,207bthat cooperatively seat in respective grooves206a,206bin a manner with permits the rails to slide along the y axis or215direction, in the grooves. The rails207a,207band grooves206a,206bcan be configured such that the rails are restricted from moving in the two directions orthogonal to the direction of travel, and as such the rails207a,207band grooves206a,206bmay be shaped so that the rails207a,207bcannot move in the x direction or in the z direction while seated in the grooves206a,206b. The cooperating rails and grooves may be implemented in a dovetail arrangement, as shown inFIG. 32, however other techniques, currently known or later developed, for slidably coupling the plate202to the bottom of plate6may be used.

Rack and pinion assemblies42can be mounted to the bottom213of translation plate202in the same configuration as such assemblies42are mounted to the bottom of moveable plate6in apparatus1. Similarly, actuation devices or actuators18a-18dare mounted to the top of movable plate6, and rack and pinions assemblies42, in the same manner as discussed above and illustrated with respect to moveable plate6in apparatus1. A plurality of respective apertures211can be provided through the width of translation plate202for receiving the actuators18and permitting movement of the actuators18along the y axis during y travel of the plate202. In some examples, the apertures211may be circular and a diameter of each of the apertures211may be selected such that the inner wall of the aperture211does not interfere with the shaft of each of the actuators18a-18dwhen the plate203is translated along the y direction. In certain examples, one or more of the apertures211may shaped as an oval, a rectangle, or an elongated slot. Any other suitable form factor may be used for the apertures211to allow the plate202to move relative the plates2,4, and/or6along the y direction.

An actuation assembly216can be included in apparatus201for translating or moving plate202relative to elevationally-adjustable plate6. In one embodiment, a plurality of linear actuators217, for example cylinder-piston type, hydraulic or electric actuators, may be utilized and controlled and/or synchronized as desired, using a programmable controller for example that is the same or in addition to the controllers discussed above. In one embodiment, first and second actuators217are provided and mounted in spaced-apart positions along the x axis to the top of moveable plate6. The piston of each actuator can be connected to a bracket or other suitable member218that is joined in a suitable manner to the top of translation plate202and extends through an opening in the moveable plate6so as to be accessible to the actuator.

Actuation assembly216permits the creasing elements13of top array10to be moveable along y axis relative to the creasing elements14of the bottom array12(seeFIG. 33). As such, the rows33of creasing elements13can be translated in the y direction relative to the corresponding rows34of creasing elements14, either during or prior to the folding process of apparatus201.

Apparatus201operates in substantially the same manner as discussed above with respect to apparatus1. In one method of operation where the straight lines87of the foldable medium60, and thus the distance between end walls72,74of the cells63of the folded structure to be formed, are greater than the length of the leading edge of the creasing element13,14, the top array10can be moved along the y axis relative to the bottom array12, for example before the creasing elements engage the foldable medium60, such that the end surface of the creasing elements in one of arrays10,12is registered along the y axis with one end of an alternating set of straight lines87of the medium60and the end surface of the creasing elements in the other of arrays10,12is registered along the y axis with the other end of each of the set of straight lines87between such alternating set. For example, the end surface130of a creasing element13can be registered with one end of a straight line87of the medium60, and the end surfaces130of the opposing creasing elements14on both sides along the x axis of such creasing element13can be registered with the other end of the two adjacent straight lines87on the medium located on opposite sides of the first line87along the x axis. During the folding process, the opposed leading edges120,122of the creasing elements13,14engage the straight lines87of the medium60during interdigitation of the creasing elements to cause such alternating straight lines87to form alternating peak folds80and valley folds86in the medium. A slight offset of the top creasing elements13relative to the bottom creasing elements14along the y axis as shown inFIG. 33, such as for example in the amounts discussed above, does not affect the folding process or the formation of cells63and wall structures82.

In the foregoing manner, apparatus201permits creasing elements13,14having leading edges120,122of fixed lengths to be utilized to form cells having a distance between end walls72,74approximately equal to the length of such leading edges120,122and to form cells having a distance between end walls72,74greater than the length of such leading edges120,122.

Other embodiments of the first or top array of creasing elements and the second or bottom array of creasing elements of the creasing assembly of the present invention, for example creasing assembly7, can be provided. An additional embodiment of an array of creasing elements that can be utilized for one or both of top array10and bottom array12of the invention is illustrated inFIGS. 34-36. Creasing array301disclosed inFIGS. 34-36can be utilized for one or both of top array10and bottom array12of the invention, including in any of the disclosures above or herein. The creasing array301is substantially similar to top array10and bottom array12and like reference numerals have been used to describe like components of arrays301,10and12.

Creasing array301is formed from a plurality of creasing elements302that are substantially similar to creasing elements13of top array10and creasing elements14of bottom array12and like reference numerals have been used to describe like components of creasing elements302,13and14. The creasing elements can be arranged in a plurality of columns303and a plurality of rows304that can extend perpendicular to the columns303. It is appreciated that some or all of creasing elements302of creasing array301can be substantially identical and, in one embodiment, for example as illustrated inFIGS. 34-36, all of creasing elements302are identical. Each individual creasing element302, which may also be referred to as a creasing member or a folding element or member, may be implemented as a generally elongate member, which may have a rectangular transverse cross section. It is appreciated that some or all of the creasing elements may be configured to have substantially any transverse cross section, for example such creasing elements may be circular or oval in the transverse cross-section such that the creasing elements are generally shaped as rods or other cylindrical members. Other form factors may be used as desired for forming some or all of the creasing elements.

In one embodiment, each creasing element302includes a first or top portion150and a second or body portion306(seeFIG. 34). Body portion306of a creasing element can include a top, distal or upper section307and a bottom, proximal or lower section308, as shown inFIG. 34. The body portion306of each creasing element302may be shaped and configured in any manner desired which accommodates coupling the body portion306of each creasing element of the array301and which further accommodates coupling the array to the actuation assembly5. In one embodiment, as discussed above, the creasing elements of each array are arranged in rows and columns such that each creasing element is adjacent to at least one and preferably a plurality of other creasing elements. For example as shown inFIG. 34, creasing element302eis adjacent to and disposed between creasing elements302d,302falong the x direction and adjacent to and disposed between creasing elements302b,302hin the y direction.

Adjacent creasing elements can be connected together using any suitable linking assemblies, including any of the linking assemblies described herein, which can permit expansion and contraction of columns of creasing elements along the y axis and expansion and contraction of rows of creasing elements along the x axis. In one embodiment, the expansion and contraction of the creasing elements in the y axis is independent of the expansion and contraction of the creasing elements in the x axis. The linking assemblies may be configured such that all creasing elements in a row304of creasing elements are moveable together in a first direction, for example along the y axis, and all creasing elements in a column303of creasing elements are moveable together in a second direction, for example along the x axis. In one embodiment, the linking assemblies, which may interchangeably be referred to herein as expandable linking assemblies or directionally expandable linking assemblies, may be implemented using y-travel scissor assemblies316and x-travel scissor assemblies317for respectively coupling together columns303of creasing elements302and rows304of creasing elements302.

Each y-travel316and x-travel317scissor assembly, which can be made from any suitable material such as metal or plastic or ceramic, can include a plurality of first and second scissor elements or links. For example, each y-travel scissor assembly316may include a plurality of first y-scissor links321and a plurality of second y-scissor links322(seeFIG. 34). The first and second y-scissor links321,322are pivotaly coupled together using a pivot means or joint that can include for example a y-center pivot element or pin323. Each y-scissor link321,322has a y-first end portion326and a y-second end327. In one embodiment, each pair of y-scissor links321,322couples together three adjacent creasing elements in a column303at the upper section307of the creasing elements302. In this regard, the y-first end326of each y-scissor link321,322may be slidably coupled to upper section307of the body portion306of one of the outer creasing elements of such three adjacent creasing elements, for example the left creasing element302, by for example using a y-moveable element or pin328slidably disposed in a respective y-slot331,332provided on the upper section307of such left creasing element302and extending longitudinally in the z direction. The y-slot331for the y-first end326of the first y-scissor link321can be in the lower portion of the upper section307, and the y-slot332for the y-first end326of the second y-scissor link322can be in the upper portion of the upper section307. The y-second end327of each y-scissor link321,322may be slidably coupled to upper section307of the body portion306of the other of the outer creasing elements of such three adjacent creasing elements, for example the right creasing element302, by for example using a y-moveable element or pin328slidably disposed in a respective y-slot332,331provided on the upper section307of such right creasing element302and extending longitudinally in the z direction. The y-slot332for the y-second end327of the first y-scissor link321can be in the upper portion of the upper section307, and the y-slot331for the y-second end327of the second y-scissor link322can be in the lower portion of the upper section307. The y-center pivot pin323is fixedly coupled within a bore (not shown) in the upper section307of the center creasing element302of such three adjacent creasing elements. In one embodiment, such bore in the creasing element302is disposed midway between the slots331,332. In one embodiment, a first y-travel scissor assembly316is coupled to one side of the creasing elements302of each column303of creasing elements and a second y-travel scissor assembly316is coupled to the other side of the creasing elements302of such column303, although it is appreciated that an embodiment can be provided where only one y-travel scissor assembly316is utilized for a column303of creasing elements302. At the outer-most rows304of creasing elements302, only half of each y-scissor link321,322is fixedly coupled by the y-center pivot pin323to the upper section307of each such end creasing element302. In this regard, a y-end portion326or327of each scissor link321,322extends from the end creasing element302to the respective slot331,332in the adjacent creasing element302disposed inwardly of the array301from such end creasing element. Each first y-scissor link321extends parallel to each other and each second y-scissor link322extends parallel to each to each and the y-travel scissor assembly316extends in a plane. Contraction of the scissor links321,322of the assembly316, by pivoting y-first end portions326away from each other about pin323and y-second end portions327away from each other about pin323, causes the y-moveable pins328of each creasing element302to move away from each other in slots331,332so as to draw the creasing elements of the array301together in the y direction in unison. Expansion of the links321,322of the assembly316, by pivoting y-first end portions326towards each other about pin323and y-second end portions327towards each other about pin323, causes the y-moveable pins328of each creasing element302to move towards each other in slots331,332so as to move the creasing elements of the array301away from each other or expand in the y direction in unison.

In a similar manner, each x-travel scissor assembly317may include a plurality of first x-scissor links341and a plurality of second x-scissor links342(seeFIG. 36). The first and second x-scissor links341,342are pivotaly coupled together using a pivot means or joint that can include for example a x-center pivot element or pin343. Each x-scissor link341,342has an x-first end portion346and a x-second end347. In one embodiment, each pair of x-scissor links341,342couples together three adjacent creasing elements in a row304at the lower section308of the creasing elements302. In this regard, the x-first end346of each x-scissor link341,342may be slidably coupled to lower section308of the body portion306of one of the outer creasing elements of such three adjacent creasing elements, for example the left creasing element302, by for example using a x-moveable element or pin348slidably disposed in a respective x-slot351,352provided on the lower section308of such left creasing element302and extending longitudinally in the z direction. The x-slot351for the x-first end346of the first x-scissor link341can be in the lower portion of the lower section308, and the x-slot352for the x-first end346of the second x-scissor link342can be in the upper portion of the lower section308. The x-second end347of each x-scissor link341,342may be slidably coupled to lower section308of the body portion306of the other of the outer creasing elements of such three adjacent creasing elements, for example the right creasing element302, by for example using a x-moveable element or pin348slidably disposed in a respective x-slot352,351provided on the lower section308of such right creasing element302and extending longitudinally in the z direction. The x-slot352for the x-second end347of the first x-scissor link341can be in the upper portion of the lower section308, and the x-slot351for the x-second end347of the second x-scissor link342can be in the lower portion of the lower section308. The x-center pivot pin343is fixedly coupled within a bore (not shown) in the lower section308of the center creasing element302of such three adjacent creasing elements. In one embodiment, such bore in the creasing element302is disposed midway between the slots351,352. In one embodiment, a first x-travel scissor assembly316is coupled to one side of the creasing elements302of each row304of creasing elements and a second x-travel scissor assembly316is coupled to the other side of the creasing elements302of such row304, although it is appreciated that an embodiment can be provided where only one x-travel scissor assembly316is utilized for a row304of creasing elements302. At the outer-most columns303of creasing elements302, only half of each x-scissor link341,342is fixedly coupled by the x-center pivot pin343to the lower section308of each such end creasing element302. In this regard, a x-end portion346or347of each scissor link341,342extends from the end creasing element302to the respective slot351,352in the adjacent creasing element302disposed inwardly of the array301from such end creasing element. Each first x-scissor link341extends parallel to each other and each second x-scissor link342extends parallel to each to each and the x-travel scissor assembly316extends in a plane. Contraction of the scissor links341,342of the assembly316, by pivoting x-first end portions346away from each other about pin343and x-second end portions347away from each other about pin343, causes the x-moveable pins348of each creasing element302to move away from each other in slots351,352so as to draw the creasing elements of the array301together in the x direction in unison. Expansion of the links341,342of the assembly316, by pivoting x-first end portions346towards each other about pin343and x-second end portions347towards each other about pin343, causes the x-moveable pins348of each creasing element302to move towards each other in slots351,352so as to move the creasing elements of the array301away from each other or expand in the x direction in unison.

The creasing elements302can be made from any suitable material such as metal, plastic or a ceramic material, and in one embodiment can be made from a rigid such material. Not all of the creasing elements need be made from the same material, for example some creasing elements can be made from a rigid plastic, some other creasing elements can be made from metal and some other creasing elements can be made from a ceramic material. In one embodiment, the top150and body306portions of each creasing element302may be formed as a single unitary structure, for example a monolithic component fabricated in one piece by molding or machining, as examples. In one embodiment, each creasing element may comprise a plurality of individual sub-components which are assembled to form the creasing element and assembled into the array301of creasing elements. In one embodiment, an end portion173of the lower section308of a creasing element302may be provided with a sliding contact surface or bearing175.

Creasing array301can operate in the same manner as discussed above, for example with respect to top array10and bottom array12. The spanning of the first and second y-scissor links321,322and the first and second x-scissor links341,342across three respective adjacent creasing elements302, and the slidable coupling together of such three adjacent creasing elements302by such respective scissor links, enhances the structural integrity and uniform movement of the creasing array301so as to increase the reliability of the operation of folding apparatus1and the quality of the folded structure formed thereby.

Examples of apparatus, systems and methods for folding a sheet of material into a folded support structure have been described herein, which apparatus, systems, and methods may afford a level of automation for achieving three dimensional folded structures as described.

An exemplary apparatus according to the present invention may include a first array of creasing elements and a second array of creasing elements, each of the creasing elements in the first and second arrays having a leading edge adapted to engage a sheet of material. The apparatus may further include at least one actuator for causing relative movement of the first and second arrays of creasing elements from a first position in which the first and second plurality of creasing elements are spaced apart to a second position in which the first and second array of creasing elements are at least partially interdigitated and for moving the creasing elements of the first array closer together and the creasing elements of the second array closer together during relative movement of the first and second arrays of creasing elements to the second position. In this manner a sheet of material can be placed between the first and second arrays of creasing elements and folded by the leading edges of the creasing elements during the relative movement of the first and second arrays creasing elements to the second position. Furthermore, the movement of the creasing elements of the first array closer together and the creasing elements of the second array closer together accommodates contraction of the sheet of material as it is folded by the first and second arrays of creasing elements.

In certain embodiments, the at least on actuator may include at least one first actuator for causing relative movement of the first and second arrays of creasing elements from the first position to the second position and at least one second actuator for moving the creasing elements of the first array closer together and the creasing elements of the second array closer together during relative movement of the first and second arrays of creasing elements to the second position. In one embodiment, an apparatus may include a plurality of arrays of creasing elements, wherein creasing elements of a first array are disposed in rows and columns and the creasing elements of a second array are disposed in rows and columns. In one embodiment, the number of columns in the first array of creasing elements may be one less than the number of columns in the second array of creasing elements. In one embodiment, the rows of creasing elements in the first array may be alignable in a plane with the rows of creasing elements in the second array.

In one embodiment, the first array of creasing elements may be moveable transversely relative to the second array of creasing elements so that the rows of creasing elements in the first array are not aligned in a plane with the rows of creasing elements in the second array. In one embodiment, the apparatus may further include at least one additional actuator for moving the first array of creasing elements relative to the second array of creasing elements so that the rows of creasing elements in the first array are not aligned in a plane with the rows of creasing elements in the second array when the first and second arrays of creasing elements are in the first position.

In one embodiment, the columns of creasing elements in the first array may be offset from the columns of creasing elements in the second array when viewed in plan so that that columns of creasing elements in the first array are interdigitated with the columns of creasing elements in the second array when the first and second arrays of creasing elements are in the second position. In one embodiment, the columns of creasing elements in the first array may be substantially centered between the columns of creasing elements in the second array when viewed in plan.

In one embodiment, adjacent creasing elements in each column of the first array may be interconnected by a first column scissor assembly and adjacent creasing elements in each column of the second array may be interconnected by a second column scissor assembly. In one embodiment, adjacent creasing elements in each row of the first array may be interconnected by a first row scissor assembly and adjacent creasing elements in each row of the second array may be interconnected by a second row scissor assembly.

In one embodiment, leading edges of the creasing elements of the first array may be substantially coplanar with each other when the first and second arrays of creasing elements are in the first position. In one embodiment, the leading edges of the creasing elements of the second array may be substantially coplanar with each other when the first and second arrays of creasing elements are in the first position. In one embodiment, the leading edge of the creasing elements of the second array may be substantially coplanar with each other and the leading edge of the creasing elements of the first array may be substantially coplanar with each other when the first and second arrays of creasing elements are in the first position.

While various aspects and examples have been disclosed herein, other aspects and examples will be apparent to those skilled in the art. The various aspects and examples disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.