Electrical protective devices

An electrical protector assembly for protecting a circuit from excessive current increases and excessive voltage surges, said protector assembly comprising:

• a dielectric housing for supporting said assembly;
• a current protection subassembly which comprises a dielectric base adapted to be secured to said housing, first and second electrically conductive pins supported in said base and extending therethrough, said first pin having a tubular end portion, a sleeve which has electrically conductive flanged end portions and which is disposed concentrically about said tubular end portion of said first pin and supported in an initial position by a pellet of fusible material that extends between an end portion of said sleeve and an end surface of said first pin without said pellet being secured to said sleeve by a fused portion of said pellet, and a wire having predetermined resistance characteristics which is wound about an outer surface of said sleeve with one end being connected electrically to an end portion of said sleeve and with its other end being secured to said second pin to establish a current path from said first pin through said sleeve and said wire to said second pin;
• a voltage protection subassembly which includes first and second electrodes with said first electrode engaging one flanged end of said sleeve and with said electrodes supported within said housing in a manner to provide a predetermined gap therebetween;
• a grounding subassembly which is connected electrically to said second electrode to provide a current path from said first pin through said first electrode across said gap to said second electrode and to ground during a voltage surge which is sufficient to cause the current to bridge said gap;
• resilient means disposed between said voltage protection subassembly and said housing for maintaining said first electrode in engagement with said one flanged end of said sleeve and which is rendered effective upon the melting of the pellet of fusible material caused by the flow of excessive current for causing said sleeve to be moved along said first pin to a second position where another flanged end of said sleeve engages said grounding subassembly to provide a fault current path from said first pin to said grounding subassembly.

An electrical protector assembly for protecting a circuit against excessive voltages and excessive currents, said assembly including:

• a dielectric housing;
• grounding means disposed within said housing for providing a current path to ground when excessive voltage surges and excessive currents appear in a circuit;
• a current protection subassembly which includes:
• a dielectric base;
• and
• a current responsive means for sensing excessive currents, said current responsive means including a first metallic contact element for establishing electrical contact beween a circuit and said protector assembly and a metallic sleeve which is disposed concentrically about and held adjacent to one end of said first contact element by a pellet of a fusible material which is interposed between an end of said first metallic contact element and a closed end of said sleeve, said sleeve having a conductive flange at each end thereof and windings of an insulated wire having a predetermined resistance wound about an outer surface thereof, said first contact element extending through said base and said wire having an end portion which extends to and is bonded to said sleeve adjacent to one end of said first contact element, said sleeve being adapted to establish a fault current path with said grounding means when the current increases beyond a predetermined level;
• a surge voltage protection subassembly engaging said grounding means and including means being in engagement with one of said flanges of said sleeve of said current responsive means such that an axis through said first metallic contact element of said current responsive means is offset from an axis of said surge voltage protection subassembly;
• a second metallic contact element which extends through said base, and which is connected electrically to said current responsive means through said wire which has its other end bonded to said second contact element, said second contact element and said first contact element adapted to conduct normal circuit current with the application of normal circuit voltage;
• and
• spring means disposed between said voltage protection subassembly and said housing and removed from the normal current and the fault current paths for biasing said surge voltage protection subassembly into engagement with said one of said flanges of said sleeve of said current responsive means and being effective upon the occurrence of excess heat, which is generated by current above the predetermined level and which is sufficient to melt the pellet of fusible material, to move said sleeve to cause the other flange to engage said grounding means and establish the fault current path.

An electrical protector assembly for protecting a tip conductor and a ring conductor of a circuit against excessive voltage surges and excessive current increases, said assembly comprising;

• a dielectric housing;
• a dielectric base which is snap-locked to said housing;
• grounding means secured to said base for grounding said protector assembly when excessive voltage surges and excessive currents appear in the circuit to be protected;
• a voltage protection subassembly which is associated with each conductor and which is mounted in said housing, said voltage protection subassembly including:
• a first carbon electrode;
• a second carbon electrode adapted to be connected electrically to the circuit to be protected, aligned with said first electrode, spaced a predetermined distance therefrom and cooperating with one end thereof to form a gap across which excess voltage surges may be dissipated to said grounding means;
• and
• electrically conductive supporting means for holding said first and second carbon electrodes in aligned, spaced relationship within said housing, said supporting means being connected electrically to said first carbon electrode and to said grounding means;
• a current protection subassembly which is associated with each conductor and which is mounted in said housing, each said current protection subassembly comprising:
• a first conductive tubular pin which extends through said base and which is adapted to connect the circuit to be protected to said current protection subassembly, said first pin being a line pin;
• a second conductive pin which extends through said base and which is adapted to cooperate with the line pin to conduct normal circuit current;
• a movable conductive sleeve which is held along the line in a first position and being connected electrically thereto, said movable conductive sleeve having one end in electrical engagement with said second carbon electrode;
• heat generating means compising a plurality of convolutions of wire having predetermined electrical characteristics having one end thereof connected electrically through said movable conductive sleeve to the line pin and the other end thereof connected to said second pin;
• and
• heat responsive fusible spacer means interposed between an edge surface of an end of the line pin and said one end of said sleeve which is in engagement with said second electrode without said spacer means being secured to said sleeve by a fusible portion of said spacer means for holding said movable sleeve-adjacent to one end of the line pin in a first position and rendered effective by the occurrence of excessive current above a predetermined level for permitting said movable sleeve to be moved along the line pin to establish an electrical connection with said grounding means;
• and
• resilient means interposed between each of said voltage protection subassemblies and said housing for maintaining said second electrode in electrical engagement with said sleeve and for moving said sleeve to a second position along the line pin into engaement with said grounding means when the heat responsive means is rendered effective by an excessive amount of heat produced by said heat generating means in the presence of current flow above the predetermined level.