US4206337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave oven having improved defrost cycle timer means
Assignee: Robertshaw Controls Co
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Filing: 1978-04-12
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Granted: 1980-06-03
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Expires: 1998-04-12
Abstract
Abstract A microwave oven having an electrical switch construction provided with an electrical switch that in one operating condition thereof operates the power unit of the oven and that in another operating condition thereof turns off the power unit. A timer is operatively associated with the switch for causing the switch to be repetitively in one of the conditions thereof a certain percentage of a certain increment of time and for being in another condition thereof for the remainder of the certain increment of time, the timer being adapted for selecting the amount of the certain percentage of the certain increment of time within certain limits whereby a slow to fast defrost cycle of the oven can be provided. The timer includes a rotatable cam member having a cam part for caming the switch to one of the operating conditions thereof during each revolution of the cam member, the cam part of the cam member being radially moveable relative thereto. The timer is adapted for selecting a radial position of the cam part for caming the switch or a radial position of the cam part that will not cam the switch.
Inventors
- 👤 Edgar E. Marquis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:11
CPC Classifications
H; H01; H01H; H01H43/00; H01H43/10; H01H43/12; H01H43/125; H01H43/106
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
196 words
In a microwave oven having an electrical switch construction provided with an electrical switch that in one operating condition thereof operates the power unit of said oven and that in another operating condition thereof turns off said power unit, timer means operatively associated with said switch for causing said switch to be repetitively in one of said conditions thereof a certain percentage of a certain increment of time and for being in another condition thereof for the remainder of said certain increment of time, said timer means being adapted for selecting the amount of said certain percentage of said certain increment of time within certain limits whereby a slow to fast defrost cycle of said oven can be provided, said timer means including a rotatable cam member having a cam part for camming said switch to one of said operating conditions thereof during each revolution of said cam member, the improvement wherein said cam part of said cam member is radially movable relative thereto, said timer means being adaptable for selecting a radial position of said cam part for camming said switch or a radial position of said cam part that will not cam said switch.
Claim 2
Dependent Claim
196 words
In a microwave oven having an electrical switch construction provided with an electrical switch that in one operating condition thereof operates the power unit of said oven and that in another operating condition thereof turns off said power unit, timer means operatively associated with said switch for causing said switch to be repetitively in one of said conditions thereof a certain percentage of a certain increment of time and for being in another condition thereof for the remainder of said certain increment of time, said timer means being adapted for selecting the amount of said certain percentage of said certain increment of time within certain limits whereby a slow to fast defrost cycle of said oven can be provided, said timer means including a rotatable cam member having a cam part for camming said switch to one of said operating conditions thereof during each revolution of said cam member, the improvement wherein said cam part of said cam member is radially movable relative thereto, said timer means being adaptable for selecting a radial position of said cam part for camming said switch or a radial position of said cam part that will not cam said switch.
Claim 3
Dependent Claim
39 words
A microwave oven as set forth in claim 1 wherein said timer means is adapted for selecting a continuous operating condition of said switch whereby a continuous cook operation of said power unit for said oven can be provided.
Claim 4
Dependent Claim
35 words
A microwave oven as set forth in claim 1 wherein said certain limits comprises about 30% on time of said power unit and 70% off time thereof to 100% on time of said power unit.
Claim 5
Dependent Claim
31 words
A microwave oven as set forth in claim 3 wherein a timer motor is operatively interconnected to said timer means to cause each increment of time to be approximately one minute.
Claim 6
Dependent Claim
32 words
A microwave oven as set forth in claim 1 wherein said cam part is integral with said cam member so that said cam member and said cam part comprise a one-piece structure.
Claim 7
Dependent Claim
43 words
A microwave oven as set forth in claim 5 wherein said cam part of said cam member is hinged to said cam member by a hinge section of said cam member that has a natural resiliency to hold said cam part radially inwardly.
Claim 8
Dependent Claim
38 words
A microwave oven as set forth in claim 1 wherein said timer means includes a latch for holding said switch in said cammed position thereof each time said cam part cams said switch to that operating condition thereof.
Claim 9
Dependent Claim
49 words
A microwave oven as set forth in claim 7 wherein said timer means includes a rotatable unlatching member for operating said latch each revolution of said unlatching member to cause said switch to be unlatched from said cammed operating condition thereof to return to the other operating condition thereof.
Claim 10
Dependent Claim
69 words
A microwave oven as set forth in claim 8 wherein said cam member and said unlatching member are arranged to rotate about the same axis and respectively have interconnecting structure cooperating together to cause said cam member and said unlatching member to rotate in unison, said timer means being adapted to adjust the relative positions of said cam member and said unlatching member to thereby select said certain percentage.
Claim 11
Dependent Claim
106 words
A microwave oven as set forth in claim 9 wherein said switch comprises a pair of switch blades having a normal bias to place said blades together to provide one of said operating conditions of said switch, said cam part camming both of said blades to the other of said operating conditions where said latch holds one of said blades in said cammed position thereof, said latch being adapted to hold said one blade in said cammed position thereof while the other blade is adapted to move back to its uncammed position when said cam part is rotated by said cam member away from said blades.
Claim 12
Dependent Claim
52 words
A microwave oven as set forth in claim 9 wherein said unlatching member has a cam surface thereon which is adapted to move said cam part of said cam member to its said camming position when said unlatching member and said cam member are in certain rotational positions relative to each other.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-06-03 | 1983-12-03 | 1984-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-06-03 | 1987-12-03 | 1988-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-06-03 | 1991-12-03 | 1992-06-03 | $7700.00 | Window Closed / Lapsed |