PURPOSE: To prevent terminals from being extracted when the external terminals are pulled.

CONSTITUTION: At mounting a first and a second terminal 43 and 43 on a terminal mounting part 23, protruding parts 47 and 49 and circular rings protrusions) around the protruding parts 47 and 49 for the prevention of extraction and an insertion hole 53 for the connection with an external terminal 55 are provided. Through holes 37 and 39 for holding the protruding parts 47 and 49 of the first and the second terminal 43 and 43 and an insertion hole 41, into which the external terminal 55 is inserted, are provided. The first and the second terminal 43 and 43 are mounted on the terminal mounting part 23, inserting an end part 45 of the terminal of it from the back surface side of the front surface side of the terminal mounting part 23 through it and press fitting the protruding parts 47 and 49 into the through holes 37 and 39 of the terminal mounting part 23. Then the external terminal 55 is connected to the hole 53 of the first and the second terminal 43 and 43, inserting a tip of it to the insertion hole of the terminal mounting part 23.