Structure of lamp socket

A lamp socket comprising a socket body to hold a lamp bulb, an electric wire fastened to a top transverse wire groove on said socket body, a center metal contact plate and a side metal contact plate respectively fastened to a first through hole and a second through hole on said socket body, and a socket cap fastened to said socket body to hold down said electric wire, causing said center metal contact plate and said side metal contact plate to make electrical contact with a respective conductor of said electric wire, wherein:

• said center metal contact plate has a flanged transverse head at one end fastened to a retaining groove inside said first through hole, a pointed upright tip adjacent to said flanged transverse head for piercing the electric wire to make electrical contact with one conductor thereof, and a springy tail at an opposite end disposed inside said socket body and supported on at least one first inside projecting bearing portion inside said socket body for contact with the tip contact of the lamp bulb in said socket body;
• said lamp cap including a bottom pressure block pressed against said electrical wire, two downward plugs at two opposite sides respectively inserted into a respective plug hole on said socket body, and a curved clamping plate raised from the periphery of the socket body, each downward plug having a step at an outer side engaged with a respective projecting block inside said socket body and a threaded portion at an inner side for engaging the ring contact of the lamp bulb, said curved clamping plate including a plurality of toothed portions, which face the periphery of said socket body, a second clamping portion defined on an inner side for fastening to a tree twig, a bigger tree branch or eaves, etc., and a first clamping portion defined outside the socket body between said curved clamping plate and said socket body for fastening to a tree branch, a gutter, etc., and a keyhole-like slot at one side for fastening to the wall by a nail.