Self-contained refrigerator open door indicator
AssigneeJesse L. Sigelman
InventorsJesse L. Sigelman, Saul Miodownik
Life of this patent
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Abstract
A device for indicating that a refrigerator door is open, includes a housing which is mountable on a refrigerator in the vicinity of the refrigerator door during the use of the device. A transducer is mountable at the refrigerator door gasket for changing an electrical parameter in response to the movement of the refrigerator door from its closed position to an open position. Circuitry disposed in the housing senses the change in the electrical parameter of the transducer to produce an alarm after a preselected time delay.
Claims14
A device for indicating that a refrigerator door is open, the device comprising:
- a housing;
- means for mounting the housing on a refrigerator in the vicinity of its door during use;
- transducer means mountable at a refrigerator door gasket for changing an electrical parameter in response to the movement of the refrigerator door from its closed position to an open position, wherein the transducer means comprises capacitive sensor means including two electrically conductive coplanar plates having an insulating base and a dielectric layer thereover and adhesive means on the base for connecting the base to a gasket on the refrigerator;
- circuit means disposed in the housing for sensing the change in the electrical parameter of the transducer means to produce an alarm after a preselected time delay.
A device for indicating that a refrigerator door is open, the device comprising:
- a housing;
- means for mounting the housing on a refrigerator in the vicinity of its door during use;
- transducer means mountable at a refrigerator door gasket for changing an electrical parameter in response to the movement of the refrigerator door from its closed position to an open position;
- circuit means disposed in the housing for sensing the change in the electrical parameter of the transducer means to produce an alarm after a preselected time delay, and wherein the transducer means comprises a capacitive sensor and wherein the circuit means comprises phase shifting means receptive of a pulse train for splitting same into two out of phase pulse trains and responsive to the capacitance of the sensor to shift the phase of the two out of phase pulse trains into phase when the door is opened.
Dependencies are inferred from the claim text.