A composite spring made of a wire of a longitudinal axis curved around a spring axis in a winding direction and a method of fabrication thereof, the spring, the wire comprising a core; and fibers layers wound around the core, and an angular positioning, relative to the spring axis, of each one of the fiber layers being selected, along a length of the core, depending on the winding direction of the wire about the spring axis, to adjust at least one of: high natural frequency of the spring, resistance to buckling and resistance to tensile and compressive stress components induced by a compressive load on the spring.

Tooling for use in forming a variable taper component is provided. The tooling includes an inner mandrel and an outer mandrel disposed around the inner mandrel. The inner mandrel includes a master insert defining opposed tapered edge faces, an external surface having a variable taper and a plurality of recesses configured to receive at least a portion of the variable taper component, and a tapered internal surface. The inner mandrel also includes a plurality of interlocking pieces arranged concentrically around the master insert, and a tapered inner sleeve disposed against the tapered internal surfaces of the plurality of interlocking pieces and the master insert. The outer mandrel defines a corresponding plurality of recesses configured to receive at least a portion of the variable taper component, wherein a maximum width of the interlocking pieces and the master insert is smaller than a minimum width of ends of the variable taper component.

A wire material for an elastic member includes: inner circumferential-side reinforced fibers that are wound in a spiral form; outer circumferential-side reinforced fibers that are provided on an outer circumference of the inner circumferential-side reinforced fibers; and thermosetting resin that is provided in at least a part of the inner circumferential-side reinforced fibers and the outer circumferential-side reinforced fibers and firmly fixes the reinforced fibers with each other. An angle formed by a winding direction of the inner circumferential-side reinforced fibers and a center axis of the winding is 70 to 110. A winding direction of the outer circumferential-side reinforced fibers with respect to a center axis of the winding is along a direction of a tensile load applied to the wire material for the elastic member in accordance with a load applying torsional stress to the wire material for the elastic member as an externally applied load.

The coil spring according to the present invention is a coil spring that is formed by spirally winding a wire rod and that includes a core that is elastically deformable and a reinforced fiber layer including reinforcing fibers wound around an outer circumference of the core and a thermoset resin that firmly adheres the reinforcing fibers to one another, wherein, in at least a part of a surface layer of the reinforced fiber layer, a content percentage of the reinforcing fibers on an inner circumferential side of the coil spring is larger than a content percentage of the reinforcing fibers on an outer circumferential side of the coil spring.

A composite coil spring includes a coil body that extends along a coiled axis. The coil body includes a core and fiber layers impregnated with a polymer material. The fiber layers are arranged around the core at different radial distances from the coiled axis. Each fiber layer extend around the coiled axis at an oblique fiber angle to the coiled axis. The fiber layers include at least one glass fiber layer and at least one carbon fiber layer. Each fiber layer includes a number of fibers that is a product of a common base number of fibers multiplied by a positive non-zero integer from a set of positive non-zero integers. The positive non-zero integer of at least one of the fiber layers is different from the positive non-zero integer of at least one other of the fiber layers.

A method for forming a three-dimensionally (3D) printed flexible support apparatus includes: producing arrays of V-spring elements using a 3D printing system, each array including a plurality of V-spring elements arranged in a predefined array shape, and each V-spring element having a predefined firmness or hysteresis characteristic; arranging the arrays of V-spring elements in at least one two-dimensional (2D) array grid using the 3D printing system, such that at least one V-spring element of each array is attached to a V-spring element of at least one adjacent array; and shaping the at least one array grid according to a predefined volume to form the support apparatus.

A torsion spring may be formed as a bar spring or helical spring comprising a spring wire of fiber composite material. In some examples, the torsion spring comprises a number of layers of fiber reinforcement, which are impregnated with a matrix material. The layers may comprise tensile-loaded fibers and compression-loaded fibers. Groups of layers of the same loading direction may exist and, seen from an inside to an outside, the group stiffness of at least two groups may differ. Likewise, methods for making such torsion springs of fiber composite material are disclosed.

An inner mandrel for forming a variable taper component includes a plurality of interlocking pieces and a brace. Each interlocking piece defines opposed tapered edge faces, a first surface, and a tapered second surface opposite the first surface. One of the edge faces defines a locking feature and another of the edge faces defines a receiving feature engaging the locking feature of an adjacent interlocking piece. The first surface defines a variable taper and a plurality of recesses. The brace secures the plurality of interlocking pieces to each other in a concentric arrangement about a central axis. A maximum width of each of the interlocking pieces is smaller than a minimum width of an end portion of the variable taper component. A central portion of the variable taper component is wider than the end portions.

A coil spring includes: a core that is elastically deformable; and a reinforced fiber layer including reinforced fibers wound around an outer circumference of the core, and a thermoset resin that firmly adheres the reinforced fibers to one another. In at least a part of a surface layer of the reinforced fiber layer, a content percentage of the reinforced fibers on an inner circumferential side of the coil spring is larger than a content percentage of the reinforced fibers on an outer circumferential side of the coil spring.

A wire material for an elastic member includes: inner circumferential-side reinforced fibers that are wound in a spiral form; outer circumferential-side reinforced fibers that are provided on an outer circumference of the inner circumferential-side reinforced fibers; and thermosetting resin that is provided in at least a part of the inner circumferential-side reinforced fibers and the outer circumferential-side reinforced fibers and firmly fixes the reinforced fibers with each other. An angle formed by a winding direction of the inner circumferential-side reinforced fibers and a center axis of the winding is 70 to 110. A winding direction of the outer circumferential-side reinforced fibers with respect to a center axis of the winding is along a direction of a tensile load applied to the wire material for the elastic member in accordance with a load applying torsional stress to the wire material for the elastic member as an externally applied load.