Refrigerator door ajar detection system

• US 4,891,626 A
• Filed: 01/18/1989
• Issued: 01/02/1990
• Est. Priority Date: 01/18/1989
• Status: Expired

• Current Assignee: Neumann Industries, Inc.
• Original Assignee: Neumann Industries, Inc.
• Inventors: Neuman, Charles E.
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US07/298,031
• Time in Patent Office: 349 Days
• Field of Search: 340/547, 340/686, 340/529, 200/61.62, 200/61.69, 62/131, 49/13
• US Class Current: 340/547
• CPC Class Codes: F25D 2700/02 Sensors detecting door opening
• CPC Class Codes: F25D 29/008 Alarm devices
• CPC Class Codes: G08B 21/18 Status alarms G08B21/02 takes precedence

Abstract

A door status detection system is provided for use in a refrigerator having a cabinet defining first and second food storage compartments and corresponding first and second doors hingely mounted to the cabinet for selectively closing the compartments. The doors each include a magnetic sealing strip secured thereto for sealing the doors to the cabinet and for maintaining the doors in closed position. First and second switch arrays are installed into the cabinet generally adjacent a section of the magnetic sealing strips of the first and second doors, respectively, when the doors are in closed position for signaling the opened/closed status of the doors. The first and second switch arrays are electrically connected in series and operated by the magnetic sealing strips of the doors. Circuitry is connected to the first and second switch arrays for signaling a user of the refrigerator if either of the doors remains in an opened position for a defined period of time. The first and second switch arrays each comprise two reed switches electrically connected in parallel and angularly oriented relative to the sealing strips to accommodate a positional range of the strips relative to the cabinet. Alternately, the first and second switch arrays may comprise Hall Effect switches preferably mounted along an axis which is angularly oriented relative to the strips to effect a staggered relation of the Hall Effect switches relative to the strips.

Claims

1. A door status detection system for use in a refrigerator having a cabinet defining a food storage compartment and a door hingedly mounted to said cabinet for selectively closing said compartment, said door including a magnetic sealing strip secured thereto for sealing said door to said cabinet and for maintaining said door in a closed position, said door status detection system comprising:

switch array means installed into said cabinet generally adjacent a section of said magnetic sealing strip when said door is in a closed position for signaling the opened/closed status of said door, said switch array means being operated by said magnetic sealing strip; and

circuit means connected to said switch array means for signaling a user of said refrigerator if said door remains in an opened position for a defined period of time.

2. A door status detection system for use in a refrigerator as claimed in claim 1 wherein said switch array means comprises at least two reed switches electrically connected in parallel with one another, said at least two reed switches being positioned side-by-side and generally axially aligned with said magnetic sealing strip to accommodate a positional range of said door and accordingly said magnetic sealing strip relative to said cabinet.

3. A door status detection system for use in a refrigerator as claimed in claim 2 wherein said at least two reed switches are positioned substantially parallel to one another.

4. A door status detection system for use in a refrigerator as claimed in claim 3 wherein said circuit means comprises:

signal means for alerting a person in the vicinity of said refrigerator that said door has been open for a defined period of time;

storage means connected to said signal means for activating said signal means upon receipt of a first one of a periodically occurring series of signal activation pulses; and

oscillator means for generating said series of signal activation pulses having a period corresponding to said defined period of time, said oscillator means being connected to and activated by said switch array means upon opening of said door.

5. A door status detection system for use in a refrigerator as claimed in claim 4 wherein said storage means comprises a flip-flop circuit which is cleared by said switch array means upon opening of said door and set by the first one of said periodically occurring series of signal activation pulses.

6. A door status detection system for use in a refrigerator as claimed in claim 1 wherein said switch array means comprises at least two reed switches electrically connected in parallel with one another, said at least two reed switches being positioned adjacent one another and angularly oriented relative to said magnetic sealing strip to accommodate a positional range of said door and accordingly said magnetic sealing strip relative to said cabinet.

7. A door status detection system for use in a refrigerator as claimed in claim 6 wherein said at least two reed switches are positioned substantially parallel to one another.

8. A door status detection system for use in a refrigerator as claimed in claim 7 wherein said circuit means comprises:

signal means for alerting a person in the vicinity of said refrigerator that said door has been open for a defined period of time;

storage means connected to said signal means for activating said signal means upon receipt of a first one of a periodically occurring series of signal activation pulses; and

oscillator means for generating said series of signal activation pulses having a period corresponding to said defined period of time, said oscillator means being connected to and activated by said switch array means upon opening of said door.

9. A door status detection system for use in a refrigerator as claimed in claim 8 wherein said storage means comprises a flip-flop circuit which is cleared by said switch array means upon opening of said door and set by the first one of said periodically occurring series of signal activation pulses.

10. A door status detection system for use in a refrigerator as claimed in claim 1 wherein said switch array means comprises at least two Hall Effect switches electrically connected in parallel with one another, said at least two Hall Effect switches being staggered relative to a nominal centerline of said magnetic sealing strip to accommodate a positional range of said door and accordingly said magnetic sealing strip relative to said cabinet.

11. A door status detection system for use in a refrigerator as claimed in claim 10 wherein said at least two Hall Effect switches are aligned with one another along an axis which is angularly oriented relative to said nominal centerline to effect the staggered relation of said Hall Effect switches relative thereto.

12. A door status detection system for use in a refrigerator as claimed in claim 11 wherein said circuit means comprises:

signal means for alerting a person in the vicinity of said refrigerator that said door has been open for a defined period of time;

storage means connected to said signal means for activating said signal means upon receipt of a first one of a periodically occurring series of signal activation pulses; and

oscillator means for generating said series of signal activation pulses having a period corresponding to said defined period of time, said oscillator means being connected to and activated by said switch array means upon opening of said door.

13. A door status detection system for use in a refrigerator as claimed in claim 12 wherein said storage means comprises a flip-flop circuit which is cleared by said switch array means upon opening of said door and set by the first one of said periodically occurring series of signal activation pulses.

14. A door status detection system for use in a refrigerator having a cabinet defining first and second food storage compartments and corresponding first and second doors hingedly mounted to said cabinet for selectively closing said first and second compartments, respectively, said doors each including a magnetic sealing strip secured thereto for sealing said doors to said cabinet and for maintaining said doors in closed positions, said door status detection system comprising:

first and second switch array means installed into said cabinet generally adjacent a section of the magnetic sealing strips of said first and second doors, respectively, when said doors are in closed positions for signaling the opened/closed status of said doors, said first and second switch array means being electrically connected in series and operated by the magnteic sealing strips of said first and second doors, respectively; and

circuit means connected to said first and second switch array means for signaling a user of said refrigerator if either of said doors remains in an opened position for a defined period of time.

15. A door status detection system for use in a refrigerator as claimed in claim 14 wherein said first and second switch array means each comprise at least two reed switches electricallyconnected in parallel with one another, said at least two reed switches being positioned side-by-side and generally axially aligned with the magnetic sealing strips of said first and second doors to accommodate a positional range of said doors and accordingly said magnetic sealing strips relative to said cabinet.

16. A door status detection system for use in a refrigerator as claimed in claim 15 wherein said circuit means comprises:

signal means for alerting a person in the vicinity of said refrigerator that one or both of said doors has been open for a defined period of time;

storage means connected to said signal means for activating said signal means upon receipt of a first one of a periodically occurring series of signal activation pulses; and

oscillator means for generating said series of signal activation pulses, said oscillator means being connected to and activated by said switch array means upon opening of either of said doors.

17. A door status detection system for use in a refrigerator as claimed in claim 16 wherein said storage means comprises a flip-flop circuit which is cleared by said switch array means upon opening of either of said doors and set by the first one of said periodically occurring series of signal activation pulses.

18. A door status detection system for use in a refrigerator as claimed in claim 14 wherein said first and second switch array means each comprise at least two Hall Effect switches electrically connected in parallel with one another, said at least two Hall Effect switches being staggered relative to a nominal centerline of the magnetic sealing strips of said first and second doors to accommodate a positional range of said doors and accordingly said magnetic sealing strips relative to said cabinet.

19. A door status detection system for use in a refrigerator as claimed in claim 18 wherein said circuit means comprises:

signal means for alerting a person in the vicinity of said refrigerator that one or both of said doors has been open for a defined period of time;

storage means connected to said signal means for activating said signal means upon receipt of a first one of a periodically occurring series of signal activation pulses; and

oscillator means for generating said series of signal activation pulses, said oscillator means being connected to and activated by said switch array means upon opening of either of said doors.

20. A door status detection system for use in a refrigerator as claimed in claim 19 wherein said storage means comprises a flip-flop circuit which is cleared by said switch array means upon opening of either of said doors and set by the first one of said periodically occurring series of signal activation pulses.