| 摘要 |
A lamp holder includes a body provided with a recessed room, a metal helical cylinder fitted in the recessed room for a lamp bulb to screw with. The body has a through hole vertically in the body, and an elastic conductive unit is positioned in the through hole. A central conductor is fixed at the bottom side of the body, located at one side of the through hole and connected with one terminal of electricity. The elastic conductive unit consists of a coil spring and a conductive rod fitted around by the coil spring. The conductive rod has its lower end normally separated from the central conductor by the elasticity of the coil spring. Unless a lamp bulb is screwed in the helical cylinder completely, it cannot push down enough the conductive rod to let electricity get through to light up the lamp bulb. Thus the safety of the lamp holder is enhanced.
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