Patent ID: 8101874

Claim:
A watertight junction box, comprising: a box body, said box body comprising a threaded neck, an opening transversely cut through said threaded neck to separate said threaded neck into two symmetrical halves for mounting an external power wire, an accommodation chamber defined beneath said threaded neck, an insertion hole cut through one side of said accommodation chamber, a modular cable inserted through said insertion hole into said accommodation chamber, and two sharp copper contacts mounted in said accommodation chamber at two sides and respectively kept in contact with said modular cable electrically; a lower floating plate set in said accommodation chamber, said lower floating plate having two through holes for said sharp copper contacts to pass through; an upper floating plate set in said accommodation chamber above said lower floating plate, said upper floating plate having two through holes corresponding to the through holes of said lower floating plate for said sharp copper contacts to pass through; a predetermined amount of a soft rubber filled in said accommodation chamber in between said lower floating plate and said upper floating plate; a holding down plate set in said box body and adapted to hold down an external power wire being set in said opening of said box body on said upper floating plate; and a screw cap for threading onto said threaded neck of said box body, said screw cap comprising an inside stop wall; wherein when said screw cap is threaded onto said threaded neck of said box body after an external power wire is set in said opening of said box body between said upper floating plate and said holding down plate, said inside stop wall of said screw cap is forced downwardly against said holding down plate, said external power wire, said soft rubber and said lower floating plate, causing said sharp copper contacts to cut into said external power wire and said soft rubber to wrap about the connection area between said sharp copper contacts and said external power wire.