Abstract: A bolt and nut assembly with loosening prevention including: a bolt; a nut screw-coupled with a screw thread of the bolt; an anti-loosening cap for receiving the nut therein to prevent the nut from moving in a loosening direction that the nut is released from the bolt; and a nut locking member coupled with the screw thread of the bolt penetrating through the nut, and accommodated in the anti-loosening cap together with the nut. The anti-loosening cap includes: a nut receiving cap for receiving the nut therein; and a bolt receiving cap disposed at an upper portion of the nut receiving cap and having a bolt exposure hole for exposing an end portion of the bolt penetrating through the nut to the outside. The nut locking member includes a coil spring coupled with the screw thread of the bolt, which penetrates through the nut in a predetermined length.

Abstract: Disclosed herein is an anchor bolt for a hollow wall including: a core shaft having an inner bolt insertion hole perforated therein in an axial direction; an inner bolt screw-coupled to the inner bolt insertion hole; and an expansion locking tube arranged between the core shaft and the inner bolt to surround the inner bolt. The expansion locking tube and the inner bolt are combined with the core shaft and are inserted into a through hole of the hollow wall. When the inner bolt is screw-coupled to the inner bolt insertion hole and is inserted into the core shaft, the expansion locking tube is bent to be expanded outwards in a radial direction of the core shaft so that an elastic force is applied in a resistant direction to a direction that the core shaft is outwardly separated from the through hole.

Abstract: The present invention relates to a side-discharge type nondirectional air purifier including: a housing extended in a vertical direction thereof and having a plurality of discharge holes formed on an outer peripheral surface thereof; a fan seated onto a top end periphery of the housing and adapted to absorb external air and to discharge the absorbed external air toward a bottom surface of the housing; a spiral wing disposed vertically in an internal space of the housing; a perforated board for pressure adjustment disposed outside the spiral wing and having a plurality of air ventilation holes formed piercedly thereon; and a main filter disposed vertically inside the housing in such a manner as to be surroundingly located outside the perforated board.

Abstract: The present invention relates to a bolt structure including: a base bolt having one side end portion inserted into holes formed at the time when a fixed structure and an object to be fixed are laid on top of each other; a core bolt adapted to be advanceably and retreatably screw-coupled to the base bolt; a nut fastened to the end portion of the base bolt protruding from the holes to maintain the state where the fixed structure and the object to be fixed are laid on top of each other; locking units adapted to selectively pressurize the external surface of the nut to prevent the escape of the base bolt; and a restraint unit adapted to be advanceably and retreatably screw-coupled to the base bolt and come into contact with the end portion of the core bolt to restrain the advancement and retreat of the core bolt.

Abstract: The present invention relates to a double nut including: a double nut part having a lower nut fastened to a lower peripheral surface of a protruding region of a bolt inserted protrudingly into fastening holes formed on fastening objects to be fastened together and an upper nut fastened to an upper peripheral surface of the protruding region of the bolt; and an anti-loosening part disposed between the lower nut and the upper nut to apply elasticity to the lower nut and the upper nut in a direction where the lower nut and the upper nut are distant from each other, wherein the lower nut and the upper nut have locking grooves concavely formed on top and underside thereof, so that one end and the other end of the elastic coil spring are locked onto the locking grooves.

Abstract: The present invention relates to a bolt structure including: a base bolt having one side end portion inserted into holes formed at the time when a fixed structure and an object to be fixed are laid on top of each other; a core bolt adapted to be advanceably and retreatably screw-coupled to the base bolt; a nut fastened to the end portion of the base bolt protruding from the holes to maintain the state where the fixed structure and the object to be fixed are laid on top of each other; locking units adapted to selectively pressurize the external surface of the nut to prevent the escape of the base bolt; and a restraint unit adapted to be advanceably and retreatably screw-coupled to the base bolt and come into contact with the end portion of the core bolt to restrain the advancement and retreat of the core bolt.