A resin part, wherein the resin part has an asymmetrical shape in a thickness direction, so that a portion in which an increase in internal temperature by heating is relatively quick is positioned closer to one end of the resin part in the thickness direction while a portion in which an increase in internal temperature by heating is relatively slow is positioned closer to the other end of the resin part in the thickness direction, wherein the resin part has an asymmetrical shape in a width direction, so that the portion in which the increase in internal temperature by heating is relatively quick is positioned closer to one end of the resin part in the width direction while a portion in which an increase in internal temperature by heating is relatively slow is positioned closer to the other end of the resin part in the width direction.

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.

Disclosed herein are an electrically conductive stretchable interconnect using a twisted nature of yarn fibers and a method of manufacturing the same. According to an exemplary embodiment of the present invention, the electrically conductive stretchable interconnect includes: an elastic body in which a stretchable tunnel is formed in a length direction; and a conductive twisted yarn including a stretchable structure positioned inside the stretchable tunnel and extended by a force applied in the length direction and an extending part extending from the stretchable structure to an outside of the elastic body.

A protective tube for a coil spring and a method for manufacturing the same are disclosed herein. The protective tube for a coil spring is manufactured by: mixing 40-70 parts by weight of a thermoplastic elastomer, 20-40 parts by weight of a thermoplastic resin, 0.2-5 parts by weight of an antioxidant, and 0.2-5 parts by weight of a crosslinking agent to obtain a mixture; pelletizing the mixture to obtain pellets; extrusion-molding the pellets into a tube; crosslinking the tube by radiation; enlarging the diameter of the crosslinked tube while forming the tube into a spiral shape by heating; and setting the enlarged-diameter tube by cooling.

A composite coil spring includes a coil body that extends along a coiled axis. The coil body includes a polymer matrix and, disposed in the polymer matrix, a carbon fiber core and a plurality of fiber layers wrapped around the carbon fiber core in alternating oblique fiber angles to the coiled axis. The fiber layers include, from inside-out starting from the carbon fiber core, at least two consecutive carbon fiber intermediate fiber layers of alternating oblique fiber angles to the coiled axis, immediately followed by at least two consecutive glass fiber intermediate fiber layers of alternating oblique fiber angles to the coiled axis, and immediately followed by a carbon fiber outermost fiber layer.