US3659068A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave oven safety interlock
Assignee: Heath Co
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Filing: 1970-09-23
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Granted: 1972-04-25
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Expires: 1990-09-23
Abstract
Abstract A safety latching device for a microwave oven in which the oven door can not be opened until the microwave generator circuit in the oven has been deenergized and wherein power can not be applied to the microwave generator circuit until the oven door has been latched to a closed position against the oven cavity.
Inventors
- 👤 Gordon Duffner
- 👤 Robert D Fernau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:38
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/6414; H05B6/6417
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
143 words
In a microwave oven including a heating cavity, a microwave generator circuit energizable by a source of operating potential for supplying microwave energy to said cavity, and a door providing access to said cavity, the combination comprising: switch means including a plurality of contact members providing a circuit path for connecting said operating potential to said generator circuit when the oven door is closed; camming means carrying one of said contact members and rotatable to a first position for opening said door and to a second position for latching said door closed, the other of said contact members positioned to make electrical contact with said one contact member upon rotation of said camming means to said second position; and means coupled to said camming means for driving said camming means from said second to said first position to permit opening of said door.
Claim 2
Dependent Claim
143 words
In a microwave oven including a heating cavity, a microwave generator circuit energizable by a source of operating potential for supplying microwave energy to said cavity, and a door providing access to said cavity, the combination comprising: switch means including a plurality of contact members providing a circuit path for connecting said operating potential to said generator circuit when the oven door is closed; camming means carrying one of said contact members and rotatable to a first position for opening said door and to a second position for latching said door closed, the other of said contact members positioned to make electrical contact with said one contact member upon rotation of said camming means to said second position; and means coupled to said camming means for driving said camming means from said second to said first position to permit opening of said door.
Claim 3
Dependent Claim
76 words
The combination as defined in claim 1 wherein said means for driving said camming means includes: an electromagnet having a winding and an armature core coupled to said camming means so as to rotate said camming means and unlatch said door when said winding is energized; an electrical circuit coupling said potential source to said winding; and manually operated means mounted on said door for selectively completing said electrical circuit and thereby selectively energizing said winding.
Claim 4
Dependent Claim
34 words
The combination as defined in claim 2 and further including: a handle mounted on said door and housing said switch means, said handLe including means for depressing said switch means to energize said winding.
Claim 5
Dependent Claim
118 words
In a microwave oven having a cooking cavity, a door providing access to said cavity, and a generator source for feeding microwave energy to said cavity, the combination comprising: camming means rotatable to a first position for locking said door closed and to a second position for unlocking said door; electromagnetic means including a coil winding and an armature core said core coupled to said camming means so as to rotate said camming means to said second position when said winding is energized; a first circuit for energizing said generator source in response to rotation of said camming means to said first position; and a second circuit for energizing said winding so as to open said oven door.
Claim 6
Dependent Claim
118 words
In a microwave oven having a cooking cavity, a door providing access to said cavity, and a generator source for feeding microwave energy to said cavity, the combination comprising: camming means rotatable to a first position for locking said door closed and to a second position for unlocking said door; electromagnetic means including a coil winding and an armature core said core coupled to said camming means so as to rotate said camming means to said second position when said winding is energized; a first circuit for energizing said generator source in response to rotation of said camming means to said first position; and a second circuit for energizing said winding so as to open said oven door.
Claim 7
Dependent Claim
84 words
The combination as defined in claim 4 wherein said first circuit includes: means providing a source of electric energy; first and second switch contact members coupled respectively to said generator source and said energy providing means, one of said switch contact members being carried by said camming means with the other of said switch contact members being positioned to electrically connect to said one contact for coupling electric energy to said generator source upon rotation of said camming means to said door closed position.
Claim 8
Dependent Claim
74 words
The combination as defined in claim 5 wherein said second circuit includes: a switch coupled between said electric energy source and said electromagnetic means; and a handle mounted on said door and coupled to said switch, said handle including means for actuating said switch to energize said winding and cause said camming means to rotate to said second position; thereby to separate said switch contact members and allow said oven door to be opened.
Claim 9
Dependent Claim
36 words
The combination as defined in claim 4 and further including: bias means coupled to said camming means for rotating said camming means from said record position to said first position when said oven door is closed.
Claim 10
Dependent Claim
34 words
The combination as defined in claim 7 and further including: an actuator arm mounted on said door so as to provide a latched engagement with said camming means upon closing of said oven door.
Claim 11
Dependent Claim
53 words
The combination as defined in claim 8 and further including: follower means for maintaining said camming means in said first position when said door is open said follower means positioned to be driven by said actuator arm upon closing of said door to release said camming means for rotation to said second position.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-25 | 1975-10-25 | 1976-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-25 | 1979-10-25 | 1980-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-25 | 1983-10-25 | 1984-04-25 | $7700.00 | Window Closed / Lapsed |