Abstract: A door closer mechanism includes a base attached to a door frame, a housing attached to a door panel and a groove formed in the housing, a lever includes one end slidably engaged with the base and another end connected to the housing with a pivot axle, a rotary member is pivotally connected to the housing with the pivot axle, a shaft is slidably engaged in the housing and pivotally connected to the rotary member with a pivot pin, and a spring biasing member is disposed in the housing and engaged with the shaft for applying a spring biasing force onto the shaft and for biasing the shaft toward one end portion of the channel of the base.

Abstract: A door closer includes a damping device having a cylindrical housing which has a compartment formed by an inclined inner peripheral surface and which includes a greater inner diameter at one end than the other end, a cap attached to the cylindrical housing and having an air perforation for an air to flow into and out of the cylindrical housing, a piston rod slidably engaged in the cylindrical housing, and a sleeve attached to the piston rod and having an outer diameter for engaging with the inner peripheral surface of the cylindrical housing at one end of the cylindrical housing, but not engaged with the inner peripheral surface at the other end of the cylindrical housing.

Abstract: A door closer includes a damping device having a cylindrical housing which has a compartment formed by an inclined inner peripheral surface and which includes a greater inner diameter at one end than the other end, a cap attached to the cylindrical housing and having an air perforation for an air to flow into and out of the cylindrical housing, a piston rod slidably engaged in the cylindrical housing, and a sleeve attached to the piston rod and having an outer diameter for engaging with the inner peripheral surface of the cylindrical housing at one end of the cylindrical housing, but not engaged with the inner peripheral surface at the other end of the cylindrical housing.

Abstract: A socket device has an upper casing, a lower casing coupling with the upper casing, a copper plate disposed in an interior of the socket device, two conductive devices disposed in the interior of the socket device, and one or more switch devices inserted in the upper casing. The upper casing has a number of through holes, a number of receptacles, a number of upper clamp bars, and a number of upper separation plates. Each upper clamp bar has a distal notch. Each receptacle has two slots. The driven plate is inserted in the respective through hole. The lower casing has a number of lower clamp bars, and a number of lower separation plates. Each lower clamp bar has an end notch.