Rolling-ball tilt switch

A rolling-ball tilt switch adapted to be electrically connected to a circuit board that is on a reference surface, said rolling-ball tilt switch comprising:

• a conductive housing adapted to be secured to the circuit board, and having
• an inner surface that is adapted to surround a longitudinal axis parallel to the circuit board, and that defines a roller cavity,
• an outer surface that surrounds and is opposite to said inner surface,
• a rim end surface that interconnects said inner surface and said outer surface, and
• a distal end surface that interconnects said inner surface and said outer surface, and that is opposite to said rim end surface along the longitudinal axis,
• said inner surface having
• a first surface portion that is adjacent to said rim end surface, and
• a second surface portion that extends from said first surface portion along the longitudinal axis towards said distal end surface, and that has
• a first section connected to said first surface portion and gradually converging towards said distal end surface, and
• a second section connected to an end of said first section which is opposite to the first surface portion, and gradually converges towards said distal end surface,
• the longitudinal axis and an extension of said first section of said second surface portion of said inner surface cooperatively defining a first angle that ranges from 2 to 12 degrees, the longitudinal axis and an extension of said second section of said second surface portion of said inner surface cooperatively defining a second angle that is not larger than 90 degrees and that is larger than the first angle;
• an insulating seat connected to said rim end surface and fittingly inserted into said roller cavity;
• a conductive terminal having a protruding section extending through said insulating seat into said roller cavity and cooperating with said insulating seat to seal an end of said roller cavity adjacent to said rim end surface;
• and
• a ball unit disposed in said roller cavity, and movable along said second surface portion between a conducting position, where said ball unit is concurrently in contact with said protruding section of said conductive terminal and said second surface portion, and a non-conducting position, where said ball unit is separated from said protruding section of said conductive terminal.