A fiber-reinforced plastic leaf spring and a method for producing the fiber-reinforced plastic leaf spring are provided, which is suitable in particular for use in a motor vehicle. It has an elongate leaf spring main body which comprises a first eye bushing at a first end and a second eye bushing at a second end. The leaf spring main body and the first and second eye bushings are formed using at least a first layer and a second layer of a composite material. Each of the layers is guided along a centerline of the leaf spring main body to form the leaf spring main body and, to form the first and second eye bushings, is respectively wrapped around a bushing element having a first center axis and around a bushing element having a second center axis.

An illustrative example composite leaf spring includes first and second bushing tubes near longitudinal ends. A ribbon of base material is wrapped at least partially around the first and second bushing tubes. The base material has a width that defines a width of the leaf spring. First portions of the base material are near the longitudinal ends and a second portion is between the first portions. The second portion is thicker than the first portions. A plurality of layers of a ribbon of tension material are wrapped around the base material. The tension material defines an outermost layer of the leaf spring. The tension material has warp strands in a longitudinal direction between the first and second longitudinal ends of the leaf spring and weft strands transverse to the warp strands. The warp strands establish a majority of a composition of the tension material.

A single-leaf spring comprising a body and two eyes located at the ends of the body, with the body having an upper side and a lower side, that comprises at least one composite material sheet comprising a series of fiber sheets embedded in a polymer matrix to form a single-leaf spring, where the sheet is a single sheet that runs longitudinally along both sides of the body and the eyes of the leaf spring and that by having both sides folded creates the eyes of the leaf spring.

A single-leaf spring comprising a body and two eyes located at the ends of the body, with the body having an upper side and a lower side, that comprises at least one composite material sheet comprising a series of fiber sheets embedded in a polymer matrix to form a single-leaf spring, where the sheet is a single sheet that runs longitudinally along both sides of the body and the eyes of the leaf spring and that by having both sides folded creates the eyes of the leaf spring.

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.

Described herein is a muscle trainer including a first and a second curved, elongate spring element, the two spring elements being arranged with their concave sides facing each other, having joint elements at their respective end areas and being connected to each other at their two end areas via joints formed from the joint elements. Also described herein is a method for producing such a muscle trainer.

A muscle trainer comprising curved, elongate spring elements is disclosed. The spring elements are arranged with facing concave sides and include end areas formed at each of the ends of the spring elements. The muscle trainer includes a first joint element being formed at a first end area of each spring element and a second joint element being formed at a second end area of each spring element. The spring elements are connected at their two end areas via joints formed from the joint elements. The first joint elements are designed as brackets having a bend in the direction of the concave side of the respective spring element and in each case at least partially enclosing the second joint element of the respective other spring element. A method for producing the muscle trainer and its use as a hand trainer are disclosed.

A method of making a carbon fiber wave spring includes forming a disc-shaped ring from prepreg carbon fibers. The disc-shaped ring is then formed into a desired wave shape. The disc-shaped ring in the wave shape is then cured to form a wave spring.

A fiber-reinforced plastic leaf spring and a method for producing the fiber-reinforced plastic leaf spring are provided, which is suitable in particular for use in a motor vehicle. It has an elongate leaf spring main body which comprises a first eye bushing at a first end and a second eye bushing at a second end. The leaf spring main body and the first and second eye bushings are formed using at least a first layer and a second layer of a composite material. Each of the layers is guided along a centerline of the leaf spring main body to form the leaf spring main body and, to form the first and second eye bushings, is respectively wrapped around a bushing element having a first center axis and around a bushing element having a second center axis.

The present invention is to provide a bound stopper, which has high mechanical strength, is excellent in durability against fatigue breaking, settling or the like when a heavy load is repeatedly received, and is easy to be produced, in which the bound stopper comprises a polyurethane foam obtained from a polyurethane foam composition containing an isocyanate component and a blowing agent, and the isocyanate component contains a urethane prepolymer having an isocyanate group, the urethane prepolymer being obtained from a polyol component, a polyrotaxane containing a cyclic molecule having an active hydrogen group as a constituent, and an isocyanate.