Surge protection device including a thermal fuse spring, a fuse trace and a voltage clamping device

A surge protection device for a load supplied with at least one voltage from a power source, said surge protection device comprising:

• at least two terminals adapted to receive said voltage;
• and
• a plurality of surge protection circuits, each of said surge protection circuits comprising:
• a thermal fuse spring,
• at least one means for clamping a voltage, and
• at least one fuse trace, each one of said at least one fuse trace corresponding to one of said at least one means for clamping a voltage,
• with said thermal fuse spring, one of said at least one fuse trace and a corresponding one of said at least one means for clamping a voltage being electrically interconnected in series between said terminals, in order to form at least one series electrical connection between said terminals,
• with said thermal fuse spring being adapted to disconnect said at least one series electrical connection between said terminals under first fault conditions of said at least one means for clamping a voltage, said first fault conditions including a first current through one of said at least one means for clamping a voltage for a first duration,
• with said thermal fuse spring and said at least one fuse trace being adapted to cooperatively disconnect a corresponding one of said at least one series electrical connection between said terminals under second fault conditions of said at least one means for clamping a voltage, said second fault conditions including a second current through one of said at least one means for clamping a voltage for a second duration,
• with said second current being greater than said first current,
• with said first duration being greater than said second duration, and
• wherein said terminals include a phase input, a neutral input, and a ground input;
• and wherein said at least one means for clamping a voltage includes a plurality of first metal oxide varistors between said phase input and said neutral input, and a plurality of second metal oxide varistors between said phase input and said ground input.

A surge protection device for a load supplied with at least one voltage from a power source, said surge protection device comprising:

• at least two terminals adapted to receive said voltage;
• and
• a plurality of surge protection circuits, each of said surge protection circuits comprising:
• a thermal fuse spring,
• at least one means for clamping a voltage, and
• at least one fuse trace, each one of said at least one fuse trace corresponding to one of said at least one means for clamping a voltage,
• with said thermal fuse spring, one of said at least one fuse trace and a corresponding one of said at least one means for clamping a voltage being electrically interconnected in series between said terminals, in order to form at least one series electrical connection between said terminals,
• with said thermal fuse spring being adapted to disconnect said at least one series electrical connection between said terminals under first fault conditions of said at least one means for clamping a voltage, said first fault conditions including a first current through one of said at least one means for clamping a voltage for a first duration,
• with said thermal fuse spring and said at least one fuse trace being adapted to cooperatively disconnect a corresponding one of said at least one series electrical connection between said terminals under second fault conditions of said at least one means for clamping a voltage, said second fault conditions including a second current through one of said at least one means for clamping a voltage for a second duration,
• with said second current being greater than said first current,
• with said first duration being greater than said second duration,
• wherein said thermal fuse spring includes a first spring member, which is electrically connected to one of said terminals, and a second spring member;
• wherein said at least one fuse trace is a fuse trace having an input, which is electrically connected to said second spring member, and an output;
• and wherein said means for clamping a voltage has a first lead, which is electrically connected to the output of said fuse trace, and a second lead, which is electrically connected to another one of said terminals, and
• wherein said surge protection circuits include a printed circuit board;
• and wherein said fuse trace includes a first conductive trace on said printed circuit board, a conductive through hole in said printed circuit board, and a second conductive trace on said printed circuit board, with said first conductive trace being electrically connected to the input of said fuse trace and to said conductive through hole, and with said second conductive trace being electrically connected to said conductive through hole and to the output of said fuse trace.

A surge protection device for a load supplied with at least one voltage from a power source, said surge protection device comprising:

• at least two terminals adapted to receive said voltage;
• and
• a plurality of surge protection circuits, each of said surge protection circuits comprising:
• a thermal fuse spring,
• at least one means for clamping a voltage, and
• at least one fuse trace, each one of said at least one fuse trace corresponding to one of said at least one means for clamping a voltage,
• with said thermal fuse spring, one of said at least one fuse trace and a corresponding one of said at least one means for clamping a voltage being electrically interconnected in series between said terminals, in order to form at least one series electrical connection between said terminals,
• with said thermal fuse spring being adapted to disconnect said at least one series electrical connection between said terminals under first fault conditions of said at least one means for clamping a voltage, said first fault conditions including a first current through one of said at least one means for clamping a voltage for a first duration,
• with said thermal fuse spring and said at least one fuse trace being adapted to cooperatively disconnect a corresponding one of said at least one series electrical connection between said terminals under second fault conditions of said at least one means for clamping a voltage, said second fault conditions including a second current through one of said at least one means for clamping a voltage for a second duration,
• with said second current being greater than said first current,
• with said first duration being greater than said second duration,
• wherein said thermal fuse spring includes a first spring member, which is electrically connected to one of said terminals, and a second spring member;
• wherein said at least one fuse trace is a fuse trace having an input, which is electrically connected to said second spring member, and an output;
• and wherein said means for clamping a voltage has a first lead, which is electrically connected to the output of said fuse trace, and a second lead, which is electrically connected to another one of said terminals, and
• wherein said surge protection circuits include a printed circuit board having a first conductor which is electrically connected to one of said terminals, and a second conductor which is electrically interconnected with the input of said fuse trace;
• wherein the first spring member of said thermal fuse spring is soldered to the first conductor of said printed circuit board and the second spring member of said thermal fuse spring is stretched away from said first spring member and soldered to the second conductor of said printed circuit board.

A stretcher device for use in mounting at least one thermal fuse spring on a printed circuit board, said thermal fuse spring including a spring member having a pair of legs each of which has a hooked foot member, said stretcher device comprising:

• a base including first and second ends, first and second sides, and an elongated opening in said base;
• a first alignment member affixed to the first end of said base;
• a second alignment member affixed to the second end of said base;
• a first elongated arcuate member affixed to the first side of said base;
• and
• a second elongated arcuate member affixed to the second side of said base, with the opening of said base adapted to receive the spring member of said thermal fuse spring, and with said first and second elongated arcuate members adapted to hold the hooked foot members of said thermal fuse spring with the legs thereof being stretched thereapart for engagement with said printed circuit board.

A surge protection device for a load supplied with a voltage from a power source, said surge protection device comprising:

• a plurality of terminals adapted to receive said voltage;
• a printed circuit board;
• and
• a plurality of surge protection circuits, each of said surge protection circuits comprising:
• a thermal fuse spring on said printed circuit board,
• means for clamping a voltage,
• a fuse trace electrically interconnected in series with said thermal fuse spring and said means for clamping a voltage between said terminals, in order to form a series electrical connection between said terminals, said fuse trace including at least one conductive trace on said printed circuit board and also including a conductive through hole in said printed circuit board and electrically connected to said at least one conductive trace, and
• with said thermal fuse spring being adapted to disconnect said series electrical connection between said terminals under first fault conditions of said means for clamping a voltage, and
• with said thermal fuse spring and said fuse trace being adapted to cooperatively disconnect said series electrical connection between said terminals under second fault conditions of said means for clamping a voltage.