Various embodiments of the present technology may provide methods and apparatus for a 3D-printed spring. The 3D-printed spring may be formed from a plurality of toroidal elements spaced apart from each other and connected with a plurality of connectors. Each connector connects one toroidal element to a directly adjacent toroidal element.

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 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 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.

Apparatus for forming a pocketed spring unit, comprising a plurality of strings of pocketed springs and at least one cover sheet, comprises welding tools for welding together the pocketing material and the sheet. One of the welding tools is provided with a cutter for cutting the pocket prior to welding. The tool travels in the direction of Arrow A1, so that the cutter penetrates the pocketing material substantially centrally at the circular proximal end face of the pocket. Once inside the pocket, the tool moves axially through the centre of the spring until it reaches the distal end face of the pocket. Before the end face is reached, the piercing member becomes retracted in the direction of Arrow A2, so that the blade does not pierce the distal end face of the pocket.

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.

The invention relates to a roller casting method for producing a spiral structure, in particular a spiral structure for use in electric machines. Molten metal is supplied between a first roller and a second roller miming opposite thereto, wherein the first roller has first teeth, and the second roller has second teeth, said first and/or second teeth having tooth flanks with cavities for receiving the supplied molten metal. The teeth are designed and aligned such that the cavity of at least one tooth is at least temporarily delimited by the surface of a tooth of the other roller when the rollers are rotating such that the supplied molten metal is molded between the teeth while cooling and is molded into a section of the spiral structure.

An inner mandrel for forming a variable taper component includes a master insert and a plurality of interlocking pieces. The master insert includes opposed tapered edge faces, each tapered edge face defining at least one locking feature, a first surface having a variable taper and a plurality of recesses configured to receive a portion of the variable taper component, and a tapered second surface opposite the first surface. Each interlocking piece includes opposed tapered edge faces, one of the opposed tapered edge faces defining a locking feature and another of the opposed tapered edge faces defining a receiving feature to engage the locking feature of an adjacent interlocking piece, a first surface defining a variable taper and a plurality of recesses configured to receive a portion of the variable taper component, and a tapered second surface opposite the first surface.

An inner mandrel for forming a variable taper component includes a master insert and a plurality of interlocking pieces. The master insert includes opposed tapered edge faces, each tapered edge face defining at least one locking feature, a first surface having a variable taper and a plurality of recesses configured to receive a portion of the variable taper component, and a tapered second surface opposite the first surface. Each interlocking piece includes opposed tapered edge faces, one of the opposed tapered edge faces defining a locking feature and another of the opposed tapered edge faces defining a receiving feature to engage the locking feature of an adjacent interlocking piece, a first surface defining a variable taper and a plurality of recesses configured to receive a portion of the variable taper component, and a tapered second surface opposite the first surface.

A torsion spring may be configured as a torsion bar or a helical spring made of a spring wire made of fiber-composite material. The torsion spring may have a plurality of layers of fiber reinforcement that have been saturated with a matrix material, wherein the layers may have fibers that are tension-loaded and fibers that are compression-loaded. The at least one compression-loaded group may have a lower group stiffness than the tension-loaded group with the highest group stiffness. Methods for designing or making torsion springs made of fiber-composite material are also disclosed.