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US 4,893,101 AGranted
Resettable ground fault circuit interrupter
AssigneeEricson Manufacturing Company
InventorJames M. Robitaille
Life of this patent
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AssigneeEricson Manufacturing Company
InventorJames M. Robitaille
Estimating the term…
A resettable circuit interrupter in a ground fault detector circuit utilizes a housing which slideably retains a solenoid coil wound on a bobbin. A contact carrier is attached to the bobbin and one or more moveable contacts are provided on the carrier opposite a corresponding set of fixed contacts. A plunger slides through a central passageway in the solenoid coil. The bobbin is spring biased so that the contacts are in a normally open position. In a manually resettable version, when the solenoid coil conducts a predetermined current, manually activating the plunger causes the plunger to magnetically couple to a footplate attached to the bobbin. When a plunger spring returns the plunger to its original position, the bobbin and contact carrier move with it and the contacts are closed. When the solenoid coil conducts insufficient current to magnetically couple the plunger and footplate, the bias springs maintain the contacts in the normally open position. In an electrically resettable version the contacts may be reset by electromagnetic energy alone, without manual activation of the plunger.
A manually resettable ground fault circuit interrupter comprising a pair of normally open contacts, a housing, solenoid means slideably retained by said housing, a contact carrier attached to said solenoid means and having one of said contacts fixed thereon opposite the other contact, said solenoid means being slideable between a first position and a second position, means biasing said solenoid means towards said first position, said contacts being electronically open when said solenoid means is in said first position and said contacts being closed when said solenoid means is in said second position, and a manually actuated plunger which extends at least partially through said solenoid means and is magnetized when said solenoid means conducts a predetermined current, said plunger being slideable between a plunger first position and a plunger second position and being biased towards said plunger first position, such that when a predetermined current is conducted by said solenoid means and said plunger is manually actuated said plunger directly engages said solenoid means and upon release of said manual actuation moves said solenoid means to said second position, and when said solenoid means conducts an insufficient current said solenoid means is in said first position regardless of actuation of said plunger.
A manually resettable switch device comprising a pair of normally open contacts, one of said contacts having a fixed position and the other contact being moveable relative to said fixed contact to make and break electrical continuity therewith, said moveable contact being mounted on a contact carrier, solenoid means slideably retained by a housing, manually actuable plunger means slideable within said solenoid means and magnetically engaging said solenoid means when said plunger means is manually actuated and a predetermined current is conducted by said solenoid means, said contact carrier being attached to said solenoid means for movement therewith such that when said plunger means and solenoid means are magnetically engaged said contacts are closed upon manual actuation of said plunger means, and biasing means to disengage said plunger means from said solenoid means to open said contacts whenever the solenoid means conducts less than a predetermined current.
Resettable switching apparatus for selectively interrupting an electrical connection comprising a pair of opposing contacts, a housing, solenoid means slideable in the housing between a first and a second position, a contact carrier mounted on said solenoid means and carrying one of said opposing contacts, means biasing said solenoid means toward said first position in which said contacts are open, and a plunger extending at least partially through said solenoid means and magnetizable to hold said solenoid means in said second position in which said contacts are closed when said solenoid means conducts a predetermined current.
Dependencies are inferred from the claim text.