TECHNICAL FIELD

Systems and methods for automated, precision placement and layering of fibers without the need of a mandrel, base material or other support forms or structure. Generally this technique involves forming a winding structure with a receiving portion therein. In some embodiments the winding machine’s headstock and tail stock are driven. In some embodiments the tailstock is slaved to the headstock. The technique does not require a mandrel. The technique allows for a woven structure with a hollow center to be created, and into which additional structures can be placed.

BACKGROUND

Fibers provide significant manufacturing advantages over previous manufacturing techniques. The greater control the manufacturer has over the fiber the more control can be exercised over the mechanical properties of the final composite part. A number of fiber manufacturing techniques exist. Some manufacturers lay-up fibers by hand. This allows for placement of fiber mats, clothes, fabrics, uni-directional material, pre-impregnated clothes, fabrics or uni-directional materials. However, it is limited in manufacturing speed and accuracy of the structure to be formed.

Filament winding is another technique or process for producing fiber reinforced structures. Generally there is a mandrel that is connected at a headstock and a tail stock. The headstock is motorized and rotates the mandrel. The mandrel has enough structure to be mounted to a bearing in the tailstock. The winding process involves winding filaments under tension over a rotating mandrel. The mandrel rotates around the spindle while a delivery eye on a carriage traverses horizontally in line with the axis of the rotating mandrel, laying down fibers in the desired pattern or angle. Common filaments are glass or carbon and are impregnated in a bath with resin ahead of being wound onto the mandrel. Once the number of layers is wound to reach the desired thickness, the resin is cured. Depending on the resin system and its cure characteristics, often the rotating mandrel is placed in an oven or placed under radiant heaters until the part is cured. Once the resin has cured, the mandrel is removed or extracted, leaving the hollow final product.

Winding machines can have two, four, six or more axes of machine motion control. A two axis winding machine rotates a mandrel while the delivery eye travels horizontally along the mandrel winding the filament around the mandrel in the desired orientation. Two axis machines are best suited to winding cylindrical shaped parts. Four and six axis machines incorporate a radial axis perpendicular to carriage travel and a rotating fiber payout head mounted to the cross-feed axis. The payout head rotation can be used to stop the fiber band twisting and thus varying in width during winding. In addition, the additional winding axes allow winding around additional shapes.

In these winding processes a resin-impregnated filament is wound around the mandrel to create a composite structure or part. The structure is cured and the mandrel is removed.

One problem with this type of process is that the mandrel can be very difficult to remove once the part has been cured. However, removal of the mandrel before curing, such as when the fibers are wet, is also a difficult process.

Automated fiber placement is another advanced method of manufacturing composite materials. Fiber Placement is an automated composites manufacturing process of heating and compacting resin pre-impregnated non-metallic fibers on typically complex tooling mandrels. The fiber usually comes in the form of filaments or "tows". A tow is typically a bundle of carbon fibers impregnated with epoxy resin. Fiber placement machines generally have a capacity of 12 to 32 tows or when placing all tows at a time in a course, have respective bandwidths of 1.5 in to 4 in. The tows are fed to a heater and compaction roller on the FPM head and through robotic type machine movements, are placed in paths across a tool surface. Fibers are generally placed in orientations of 0°, +45°, -45° and 90° to build up plies which in combination, have good mechanical properties in all directions.

Automated fiber placement (AFP) machines are meant to increase rate and precision in the production of advanced composite parts. AFP machines place fiber reinforcements on molds or mandrels in an automatic fashion and use a number of separate small width tows of thermoset or thermoplastic pre-impregnated materials to form composite layups. This technology allows improved precision and increased deposition rates when compared with experienced laminators but, while allowing for more complex layup geometries than

Automated Tape Laying (ATL) it does not reach the same deposition rates. Similarly, AFP machines are limited in the size of structure they can create based on the size of the machine.

A need therefore exists for a machine and technique that provides for automated, precision placement and layering of fibers without the need of a mandrel, base material or other support form, mold or structure. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.

BRIEF SUMMARY OF THE INVENTION

The present disclosure relates generally to systems and methods for forming a winding structure without using a mandrel. In some embodiments the system comprises a mandrel-less winding machine. In some embodiments the winding machine is a lathe comprising a driven headstock comprising a pin ring, a driven tailstock comprising a pin ring wherein a tow or filament is wound between the headstock pin ring and the tailstock pin ring in selective directions and orientations. In some embodiments the winding structure is formed with additional fibers wound in selected layers. In some embodiments different fiber materials can be used in forming the same winding structure. In some embodiments the winding structure is wound in selected directions. In some embodiments the winding structure is formed to provide specific mechanical properties, such as strength, layering or fiber direction. In some embodiments, once the winding structure is formed, it is removed from the winding machine and layed over a form or mold such that the fiber orientation and layers are oriented to provide the desired mechanical properties to the form. In some embodiments the winding structure comprises a receiving portion into which a male form, such as an inflatable bladder can be placed. In some embodiments the composite winding structure and male form can then be placed into a female form such as a mold. In some embodiments the male form is inflated to allow the winding structure, or preform, to take the same form as the female mold. In some embodiments the structure is then cured. In some embodiments a method of forming a winding structure comprises forming a winding structure on a lathe with or without a mandrel.

In some embodiments a filament winding machine forms the winding structure and does not require a mandrel. In some embodiments the winding machine comprises a driven headstock. In some embodiments the winding machine comprises a driven tailstock, which optionally may be, but not necessarily is, slaved to the headstock.

In some embodiments the shape of the pin rings forms the cross-sectional shape of the winding structure. In some embodiments the system automates the selective winding of the filament in any desired pattern with a selectively modulated fiber shape, bandwidth and/or tension. In some embodiments the winding machine manipulates the headstock and tailstock to provide the selective placement of extra fiber layers in the winding structure. The winding machine can place the fibers in any direction in any functional thickness. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Example embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

Figure 1 A is an upper perspective view of an example winding machine, having a first driven element and a second driven element, according to some embodiments;

Figure 1B is an upper perspective view of the winding machine of Figure 1A, illustrating an example filament being wound onto a pin ring, according to some embodiments;

Figure 1C is another upper perspective view of the winding machine, illustrating a winding structure being wound around winding pins on a pin ring in a first direction, such as a 0° direction, according to some embodiments;

Figure 1D is another upper perspective view of the winding machine, illustrating the winding structure being wound in a second direction, such as an approximately 90° direction, according to some embodiments;

Figure 1E is another upper perspective view of the winding machine, illustrating the filament being wound in a third direction, such as an approximately 45°, according to some embodiments;

Figure 1F is another upper perspective view of the winding machine, illustrating the winding structure’s properties, according to some embodiments;

Figure 2A is an upper perspective view of an example winding machine comprising a cylindrical pin ring having a first driven element and a second driven element, according to some embodiments; Figure 2B is an upper perspective view of the winding machine of Figure 2A, illustrating an example filament being wound onto a pin ring, according to some embodiments;

Figure 2C is another upper perspective view of the winding machine of Figure 2A, illustrating a winding structure wherein the filament is wound around winding pins in a variety of directions, according to some embodiments;

Figure 3A is an upper perspective view of an example winding machine comprising a cuboidal pin ring having a first driven element and a second driven element, according to some embodiments;

Figure 3B is an upper perspective view of the winding machine of Figure 3A, illustrating an example filament being wound onto a pin ring, according to some embodiments;

Figure 3C is another upper perspective view of the winding machine of Figure 23A, illustrating a winding structure wherein the filament is wound around winding pins in a variety of directions, according to some embodiments

Figure 4 shows a method for forming a winding structure.

Figure 5 shows a method for processing a winding structure.

DETAILED DESCRIPTION OF THE INVENTION

The presently preferred embodiments of the disclosed invention will be best understood by reference to the drawings, wherein like reference numbers indicate identical or functionally similar elements. It will be readily understood that the components of the disclosed invention, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description, as represented in the figures, is not intended to limit the scope of the invention as claimed, but is merely representative of presently preferred embodiments of the invention.

Referring now to the Figures 1A-3C, an example winding machine 10 may include a first driven member and a second driven member. In some embodiments no structure, such as a mandrel or core, connects the first driven member and the second driven member. In some embodiments, the first driven member and the second driven member may be a headstock 12 and tailstock 14. In some embodiments independent structures support the headstock and the tailstock such that the distance between the two can be selectively set based on the size of the winding structure being formed.

In some embodiments the headstock and tailstock each further comprise a selectively removable pin ring 13. In some embodiments the pin ring 13 comprises a central support member with a plurality of pin rings or winding pins 17 extending from the central support member. In some embodiments winding pins 13 may extend from the central member of the pin ring at an oblique angle to allow access to the winding pin without interference from the pin ring. In some embodiments the pin 17 may comprise pointed tops, flat tops, curved lengths and a variety of other shapes. Embodiments of the pin ring may comprise a variety of cross-sectional shapes, including planar, cuboidal, parallelepiped, rectangular, triangular square, trapezoidal, ovular, elliptical, parabolic, hyperbolic, and variations of these cross- sectional shapes. The shape may comprise the shape of a mechanical part being fabricated, such as a wing, an artificial limb, or any other shape. Indeed, in some embodiments the cross- sectional shape may comprise any shape. In addition, in some embodiments the mechanical properties of the winding structure may be manipulated by varying the number of tows making up the band shape 19, or the tension placed on the individual tows during the winding process. In some embodiments the pin ring’s central support member may comprise a positioning member, such as a positioning track or pinholes into which the winding pins can be secured, to allow the spacing between the pin rings or winding pins to be selectively customized. In some embodiments a plug or cover may be used to prevent the filament from getting snagged on any features of the unused portions of the track or pinholes. In some embodiments the pins can be positioned to allow filaments being wound between the headstock and the tailstock to be wound at any desired angle between 0 degrees and 90 degrees. The angle at which the filament can be laid is determined by the angle between a first end of the headstock pin ring and a second end of the tailstock pin ring. In some embodiments the pin ring may be curved or arced to further change the angle at which the filament is wound. In some embodiments anchor pins may be selectively secured through the winding structure to provide additional locations for winding pins and allow greater control over where the filament may be placed during the winding. In some examples, after the winding structure is formed the pin may be interlaced through the wound filaments to provide a different winding angle and to allow more precision in placing filaments on the winding structure. Alternatively, in some embodiments the winding angle may be set by the position of a delivery eye and the winding structure.

Similarly, inasmuch as there is no mandrel limiting the length of the distance between the headstock and tailstock, the distance between the headstock and the tailstock can be any practicable distance, and depends on the tow or filament properties, mass, strength of the fiber and the strength of the pin rings. In some embodiments the headstock pin ring is placed a relatively short distance, less than one (1) meter, from the tailstock pin ring. In some embodiments the headstock pin ring is placed a relatively long distance, greater than fifty

(50) meters from the tailstock. In some embodiments the winding machine further comprises a delivery eye 18. In some embodiments, a first end of a filament 16 may pass through the delivery eye 18 and selectively tied to the first driven member 12 and/or a middle portion of the filament 16 may be coupled to the second driven member 14 such that the filament 16 is strung between the first driven member 12 and the second driven member 14.

In some embodiments, the headstock 12 and the tailstock 14 may rotate the respective pin rings while a delivery eye 18 of a carriage traverses from pin ring to pin ring to wind the filament around desired winding pins. In some embodiments the filament placement is selective with respect to an axis extending between the headstock pin ring 13 and the tailstock pin ring 13, to wind or layer the filament 16 in the desired position. In some embodiments wherein the winding structure 20 comprises a cylinder (Fig. 2C) or cuboid (Fig. 3C) formed between the headstock 12 pin ring 13 and a tailstock 14 pin ring 13 the winding may wrap circumferentially (hoop, approx.. 90 deg. or high angle) or helically (low angle, longitudinal) around the winding structure.

In some embodiments, the filament 16 may be wound at multiple angles, which may provide circumferential and/or longitudinal strength. In further detail, in some embodiments, a portion of the filament 16 disposed between the delivery eye 18 and the cylinder 20 may be angled with respect to the cylinder 20 or the axis extending between the first driven member 12 and the second driven member 14. In some embodiments the winding machine may comprise a plurality of delivery eyes 18 to simultaneously wind multiple filaments on the winding structure. The filament 16 can be secured in the selected angle by winding the filament between two winding pins with the desired angle. In some embodiments, the angle of the portion of the filament 16 with respect to the winding structure 20 or the axis extending between the headstock 12 and the tailstock 14 may change as the cylinder 20 is wound. In some embodiments, the fiber may be secured to a first winding pin 17 on a first pin ring and then wound around a first winding pin on the second pin ring. In some embodiments the filament may be wound around a first winding pin on a first pin ring then wound around a first winding pin on a the second pin ring, then wound back around the first winding pin on the first pin ring and then around a second winding pin on the second pin ring to create a winding pattern that will provide a winding structure to provide desired mechanical properties such as dissipate a force or energy, such as heat from a single point across the body of the winding structure. In some embodiments the filament 16 may be wound at various angles, in various orders, to form the winding structure 20.

In some embodiments, the cylinder 20 may be formed from a single, continuous filament 16. In some embodiments, the filament 16 may include glass fiber, carbon fibers and other suitable fiber material. In some embodiments, the filament 16 may include e-glass and/or one or more other suitable materials. In some embodiments, the filament 16 may include one or more of the following materials: e-glass, S2 glass, carbon, graphite, boron, ceramic, silicon carbide, thermoplastic polymer, polyether ether ketone (PEEK), etc. In some embodiments the filament may be wound dry. In some embodiments, a resin may be applied to the filament 16 to wet the filament 16. In some embodiments, the resin may be applied to the filament 16 in various ways. For example, the filament 16 may be pre-impregnated with the resin and/or pulled through a resin bath before being attached to the winding machine 10. In some embodiments, the filament 16 may be wound dry and then infused with the resin in a secondary process.

In some embodiments a mandreless winding machine 10 is provided comprising a driven headstock 12 and a driven tail stock 14. In some embodiments the headstock is controlled by a servomotor which allows for precise control of angular or linear position, velocity and acceleration of the headstock. In some embodiments the headstock can wind in a first direction, while in some embodiments the headstock can rotate in a first direction and a second direction.

In some embodiments the tailstock 14 is driven. In some embodiments the tailstock is slaved to the headstock, such that the position of the tailstock is determined by the position of the headstock 12. In some embodiments the tailstock comprises a servomotor with similar capabilities as the headstock servomotor. In some embodiments software controls the motion, speed and position of the headstock and the tailstock. In some embodiments the tailstock is mechanically slaved to the headstock such as through mechanical members, such as gears or belts, which control the speed, direction and position of the tailstock in response to the motion and position of the headstock.

In some embodiments the feed eye/delivery eye 18 comprises a carriage that can travel a first direction and a second direction longitudinally between the headstock and the tailstock. In some embodiments the feed eye can be articulated multiple directions. In some embodiments the feed eye comprises servomotors to allow the head to be selectively positioned. In some embodiments the feed eye comprises a filament control mechanism which controls the filament shape, size and tension over the band width of the fiber being wound. In some embodiments the ability of the headstock, tailstock and feed eye to be selectively positioned enables the winding machine to selectively and precisely wind the filament to form a winding structure with the filaments placed as engineered to maximize the mechanical properties.

In some embodiments the filament is run through a resin bath so that the winding structure is a wet wind. In some embodiments a dry filament is wound on the pin rings and a resin is applied to the winding structure after the winding structure is formed.

Some embodiments may comprise forming a winding structure with mechanical properties based on structural analysis such that certain structural areas require increased layering or certain filament orientation. In these embodiments the winding machine selectively winds the winding structure to place the material in the locations. In some embodiments the desired winding structure is analyzed to determine wherein a pin ring with the desired cross-sectional shape is selected and inserted into the headstock and tailstock. The filament is tied to the headstock pin ring and wound to provide filament placement, shape, bandwidth, layering and lay-up. In some embodiments the filaments is wound in the desired pattern with the filaments placed at the desired angles to provide the desired strength, elasticity, dampening, weight, conductivity or any other desired properties. In some embodiments the winding structure can be laid over the desired form. In some embodiments the desired form can be inserted into the receiving portion of the winding structure formed based on the cross-sectional area of the pin ring.

In some embodiments a method of forming a winding structure is provided. In some embodiments the method comprises providing a driven headstock 12, providing a driven tailstock 14. In some embodiments there is no mandrel between the headstock and the tailstock. In some embodiments the tailstock is slaved to the headstock. In some embodiments a filament 16 is tied to winding pin 17 extending from the pin ring 13. In some embodiments a first hoop wind is wound around a first pin ring and a second pin ring (Fig. 1C). In some embodiments the filament is wound in a second direction, such as a 90° wind (Fig. 1D). In some embodiments the winding takes place in a third direction, such as a 45°wind (Fig. 1E). In some embodiments the wind is performed in a plurality of directions such as any angle formed between the pin rings 13 or between a pin ring and a pin interlaced into the winding structure, or between a first pin and a second pin interlaced into the winding structure. In some embodiments the winding structure 20 is flexible and can be twisted and manipulated during or following the winding process to place the filament in a selected position. In some embodiments the method further comprises lacing a through a feed eye or delivery eye 18 and secured to a headstock pin ring 13 comprising a plurality of winding pins 17, and then guided by the feed eye to the tailstock pin ring 13 also comprising a plurality of winding pins 17. The plurality of winding pins on both the headstock pin ring and the tailstock pin ring allows the winding machine or lathe to selectively wind the filament and customize the mechanical properties of the form based on the tension of the fiber, the layers of fiber, the direction, orientation of the fiber, the shape of the fiber and the twist on the fiber. In some embodiments the headstock and tailstock are selectively and precisely positioned and the speed, direction and position are selectively set. In some embodiments the winding pattern for the winding structure is selected to maximize the strength of the winding structure in a first direction. In some embodiments a pattern is selected to maximize the strength of the winding structure in a second direction. In some embodiments a pattern is selected to maximize the strength of the winding structure in a plurality or third direction. In some embodiments a pattern is selected to maximize the strength of the winding structure in a combination of directions. In some embodiments this process is repeated until a winding structure is formed. In some embodiments the process is repeated until the winding structure is strengthened by winding additional filaments in selective areas to improve the mechanical performance of the winding structure in engineered ways.

In some embodiments the winding structure comprises a plank without a receiving portion (see Fig. 1) which can serve as a laminate with selective structural properties. In some embodiments a plurality of laminates, such as a first laminate and a second laminate, can be oriented and aligned on a form to give the form the desired mechanical properties. In some embodiments laminates can be layered and overlapped. In some embodiments laminates can encase an inner form. In some embodiments a composite structure is formed wherein an exterior surface material comprises the winding structure and wherein a subsurface material comprises another material selected for the desired properties. In some embodiments the form is a metal, a ceramic, a polymer or some combination thereof.

In some embodiments a winding structure comprising a receiving portion (see Figs. 2- 3) is formed. In some embodiments the receiving portion comprises a hollow or cavity substantially in the shape of the pin ring used. In some embodiments the winding structure comprises a receiving portion to receive a form, such as an inflatable bladder, an inflated bladder, or a solid form. The size of the receiving portion depends on the size of the pin ring used to wind the winding structure as well as the direction and tension of the tow used while winding the winding structure.

In some embodiments the winding structures are oriented and aligned to place the engineered portions ie layered elements or oriented fibers, in the desired locations to provide the form and the desired mechanical properties. In some embodiments the composite winding structure and form is placed in a female mold and cured.

In some embodiments, a cure profile may include several temperature stages, which may occur within a cylindrical mold. As an example, a first stage may include initial gelling and/or curing of the resin at a lower temperature, such as, for example, about l50-200°F. As another example, a second stage may include curing at a higher temperature, such as, for example, about 250-300°F. As yet another example, a third stage may include curing at an even higher temperature, such as, for example, about 350°F. In some embodiments, each stage may last between about 1-4 hours. In some embodiments, the pressure or temperature may be maintained, increased, or decreased during one or more of the stages.

In some embodiments a plurality of forms may be inserted and secured inside a receiving portion of a winding structure, allowing the winding structure to be conveyed through a female mold where the form is cured. In some embodiments the winding structure may remain in the pin ring until the structure is cured. In some embodiments, once the winding structure is cured the excess winding structure can be cut away. In some embodiments the cured winding structure can be further manufactured through grinding or other processes to provide the desired product.

In some embodiments the winding structure is wound into a parallelepiped- shaped winding structure. In some embodiments the winding structure is shaped as a cuboid. In some embodiments the winding structure is cylindrical.

In some embodiments, the forms may be secured to a CNC lathe and machined. It is contemplated that the form may be machined into the desired shape using various methods. In some embodiments, carving the form may include rough grinding using a grinding wheel, which may include a diamond abrasive grinding wheel or another suitable grinding wheel. In some embodiments, the grinding wheel may include a radius corresponding to half of a spherical shape. In some embodiments, the grinding wheel may be moved progressively along the cylinder 20 to form a row of multiple spherical shapes, which may be separated to form the spherical balls. In some embodiments, the row may include eight or more spherical shapes.

In some embodiments, carving the cylinder in Figure 2C into a ball may include placing a spherical inflatable bladder into the receiving portion, inflating the bladder, placing the winding structure into a female mold, curing the winding structure, removing excess material from the cured sphere, cutting or parting to length through a small connecting portion disposed between the spherical shape that may form a particular ball and a remaining portion of the cylinder. In some embodiments, carving the cylinder 20 into the balls may include cutting through a small connecting portion disposed between two adjacent spherical shapes that each may form a particular ball. Although the balls may be referred to in the present disclosure as being spherical, it is understood that the balls may be generally spherical in some embodiments. Similarly, it is understood that the cylinder 20 may be generally cylindrical.

Referring now to Figure 4, a flow diagram of an example method 100 of forming one or more composite structures is illustrated, according to some embodiments. In some embodiments the filament is wound dry. In some embodiments the filament is wound wet. In some embodiments the method may begin at block 101. In block 101, a resin may be applied to a filament to wet the filament.

In block 103, the filament may be tied to a winding pin 103. In some embodiments the winding pin may comprise an aperture through which a filament may be placed to secure the filament to the pin. In some embodiments the filament may be tied using a knot or wraps.

In block 105 winding filament around a pin ring 105. In some embodiments, the winding may start with several hoop. Some embodiments may start with low angle helical or longitudinal, 0 deg. winding layers. The filament may be wound at multiple angles without the core to form a winding structure. In some embodiments, the first windings may be 0° hoops followed by windings placing the filament in varying orientations to improve mechanical properties. In some embodiments, block 105 may be followed by block 107.

In block 107, the selectively adding filaments in preferred directions and orientations 107 to form a winding structure. In some embodiments the winding structure is selectively formed to place layers in specific locations or regions of the structure and in selective orientations to provide desired structural properties. The winding of the filaments is automated. The orientation and direction of the winding improves mechanical properties such as increased directional strength, vibration dampening, heat transfer, heat dissipation, electrical conductivity, weight reduction, directional tensile strength, directional strain, and directional ultimate strength. In some embodiments, block 107 may be followed by block

109. In block 109, selectively winding filaments to create layers in the winding structure 109. In some embodiments the filament may be wound in a pattern to create filament layers. In some embodiments the fiber layers are formed in a single direction. In some embodiments the fiber layers are formed from fibers being laid in more than one direction such as a plurality of directions. In some embodiments block 109 may be followed by block 111.

Block 111 comprises selectively inserting a form into a receiving portion of the winding structure. In some embodiments the receiving portion 21 is a hollow or cavity created by the cross-section used for winding the filament on pin ring. In some embodiments the form may comprise an inflatable bladder. In some embodiments the form may comprise a sphere, an ellipsoid, or a non-standard three-dimensional shape. In some embodiments the shape or tension of the filament can be modulated to allow the winding structure to conform to the surface contours of the form.

Block 119 alternatively comprises some embodiments wherein the winding structure may comprise a plank, such as shown in Figs. 1A-1F. In some embodiments the plank winding structure is selectively wound to provide improved mechanical properties described herein e.g. strength along desired selected axes, which properties are obtained through selectively winding additional filaments or layers along desired direction and in preferred locations on the plank winding form. In some embodiments multiple winding structures are used to envelop a form wherein each winding structure can be uniquely wound to achieve the desired mechanical properties. In some embodiments filaments of different dimensions, weights, strengths, or materials can be used to accomplish the desired mechanical properties. Similar techniques can be used in making a winding structure in any shape. Desired mechanical properties can be achieved through modulating filament tension, shape and layer placement in winding forms in other shapes, such as those in Figures 1A to 3C as well as the shape of any other winding structure. In some embodiments or block 111 or block 119 may be followed by block 121.

In block 121 the composite winding structure is oriented on the form. In some embodiments the placement, orientation and alignment of the winding structure on the form is automated, while in other embodiments it is manual.

In some embodiments block 111 or block 119 may be followed by block 113. In block 113, the composite winding structure and form eg inflatable bladder or form, may be placed into a female mold 113 to mold the composite in the desired shape. In some embodiments the step of block 113 may be followed by 115.

In block 115 the mold may further comprise the step of curing the composite winding structure and form 115. In some embodiments the resin or another resin may be added into the mold. In some embodiments a pressure in the mold may be increased to at least 500 psi In some embodiments a hollow structure placed in an exterior mold there will need to be an inflatable bladder or core structure inflated to approximately 50-60 PSI on the inside of the wound structure, which will limit the external pressure that can be applied. In some embodiments the resin may be cured at the pressure and a temperature of at least 250°F. In some embodiments the composite may be extracted from the mold and processed into one or more final shapes.

In block 117 some embodiments of the method may comprise processing the composite structure.

Referring now to Figure 5, a flow diagram of an example method 200 of forming a composite form is illustrated, according to some embodiments. The method may begin at block 202. In block 202, a resin may be applied to a filament to wet the filament. Alternatively the filament may be dry. In some embodiments, block 202 may be followed by block 204. In block 204, the wetted filament may be wound to form a winding structure. In some embodiments the winding structure may have a receiving portion therein. In some embodiments, the filament may be wound at multiple angles to form the winding structure. In some embodiments, a winding filament of a first material may be exchanged for the winding filament of another material. In some embodiments the filament may be wound using a winding machine without a core or mandrel. In some embodiments, the receiving portion may allow a form such as an inflatable bladder to be inserted therein. In these and other embodiments, the winding machine may include a driven headstock and a driven tailstock which may be slaved to the headstock. In some embodiments, block 204 may be followed by block 206.

In block 206, the winding structure may be placed in a female mold. In some embodiments. In some embodiments, block 206 may be followed by block 208.

In block 208, the resin or another resin may be added into the mold. In some embodiments, block 208 may be followed by block 210.

In block 210, a pressure in the cylindrical mold may be increased to at least 500 psi. In some embodiments, block 210 may be followed by block 216.

In block 216, the resin may be cured at the pressure and a temperature of at least 250°F. In some embodiments, block 216 may be followed by block 214.

In block 214, the composite may be extracted from the mold.

The method of Figure 5 may be further described with respect to one or more of Figures 1-3. Various elements used in the method of Figure 5 may also be further described with respect to one or more of Figures 1-3. For example, the winding structure, the filament, the winding machine, and the cylindrical mold may correspond to the cylinder 20, the filament 16, the winding machine 10, and the cylindrical mold 22, respectively, described with respect to one or more of Figures 1-3. Although illustrated as discrete blocks, various blocks of method 200 may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. For example, block 208 may be eliminated. Furthermore, in some embodiments, the order of the blocks may be changed.

Disclosed herein is an automated mandrel-less filament winding machine comprising a driven headstock comprising a pin ring, a driven tailstock comprising a pin ring wherein no mandrel connects the driven tailstock to the driven headstock, a delivery eye configured to guide a filament in a winding pattern onto the headstock pin ring and the tailstock pin ring, a drive mechanism to drive the headstock and drive the tailstock into positions wherein the filament is selectively wound onto the headstock pin ring and tailstock pin ring to create a winding structure.

In some embodiments the driven tail stock of the winding machine is slaved to the driven headstock. In some embodiments the headstock pin ring and tailstock pin ring further comprise winding pins configured to receive a filament. In some embodiments the delivery eye is configured to selectively guide the filament around the winding pins in a desired pattern. In some embodiments the drive mechanism comprises software-controlled servo motors configured to automate the position of the winding pins in relation to the delivery eye. In some embodiments the drive mechanism comprises mechanical members to drive and position the tailstock in response to the position and movement of the headstock. In some embodiments the headstock pin ring and tailstock pin ring are cross-sectional templates wherein a winding structure is formed upon winding a filament on the headstock pin ring and the tailstock pin ring. In some embodiments the winding structure further comprises a receiving portion. In some embodiments the winding structure comprises a form inserted into the receiving portion. In some embodiments the headstock pin ring and the tailstock pin ring are configured to selectively position the winding pins to receive the filament in a predetermined direction. In some embodiments the headstock pin ring and the tailstock pin ring are configured to selectively position the winding pins to receive the filament in a predetermined order. In some embodiments a plank is configured to laminate a form. In some embodiments the delivery eye comprises an articulation member to articulate the delivery on a plurality of axes and in a plurality of directions.

Some embodiments comprise a tensioning member to selectively adjust the tension applied to a filament. Some embodiments comprise a filament redirect configured to adjust the shape or thickness of a filament. In some embodiments the headstock pin ring and the tailstock pin ring are selectively releasable.

In some embodiments an automated mandrel-less filament winding machine comprises a driven headstock comprising a pin ring; a driven tailstock comprising a pin ring wherein the driven tailstock is slaved to the driven headstock; a driven articulating delivery eye configured to guide a filament onto the headstock pin ring and the tailstock pin ring in a predetermined winding pattern; a drive mechanism to drive the headstock into positions wherein the filament is selectively wound onto the headstock pin ring and tailstock pin ring to create a winding structure.

In some embodiments the winding machine further comprises a filament. In some embodiments the filament is wound to form a winding structure. In some embodiments the filament material is interchangeable without removing the winding structure from the winding machine.

In some embodiments an automated mandrel-less filament winding machine comprises a driven headstock comprising a pin ring; a driven tailstock comprising a pin ring wherein the driven tailstock is slaved to the driven headstock; a driven articulating delivery eye configured to guide a filament onto the headstock pin ring and the tailstock pin ring in a predetermined winding pattern; a drive mechanism to drive the headstock into positions wherein the filament is selectively wound onto the headstock pin ring and tailstock pin ring to create a winding structure.

In some embodiments a method of making a mandrel-less filament winding machine comprises providing a driven headstock comprising a pin ring; providing a driven tailstock comprising a pin ring wherein the driven tailstock is slaved to the driven headstock;

providing a driven articulating delivery eye configured to selectively guide a filament onto desired winding pins on the headstock pin ring guiding the filament onto desired winding pins on the tailstock pin ring in a predetermined winding pattern to selectively provide and position filament layers and orientations; providing a drive mechanism to drive the headstock into positions wherein the filament is selectively wound onto the headstock pin ring and tailstock pin ring to create a winding structure; inserting a form into a receiving portion formed in the winding structure; and placing the winding structure and form into a mold.

The disclosed invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments and examples are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

All examples and conditional language recited herein are intended for pedagogical objects to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Although implementations of the disclosed inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.