US4808781A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Directly driven microwave oven turntable top
Assignee: Individual
•
Filing: 1988-03-16
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Granted: 1989-02-28
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Expires: 2008-03-16
Abstract
Abstract A portable microwave oven turntable having a base assembly defining a base interior. The base assembly includes a planar bottom and upwardly extending sides supporting a circular base cover member. Within the base interior is a spring motor which may be wound to rotate a drive shaft about a vertical axis. An upper portion of the drive shaft projects from the base interior through the base cover member. Atop the base cover member a drive gear is fixed to the upper portion of the drive shaft. The drive gear has a plurality of radially extending arms having coplanar upper surfaces and opposed lateral edges. A circular tabletop is rested upon the radial arms of the drive gear and tabletop teeth or projections engage the lateral edges of the radial arms. The tabletop projections extend downwardly from the lower surface of the tabletop and project radially inwardly from an annular hub. Rotation of the tabletop is translated directly from the drive shaft via the radial arms. A gear train governs the rotational speed of the tabletop.
Inventors
- 👤 Yiu-Ching Liu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:38
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/6408; H05B6/6411
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
231 words
A portable microwave oven turntable comprising, a base having a horizontal bottom and upwardly extending sides to form a base interior, a motor means disposed within said base interior, a central drive shaft attached to said base to form a vertical axis of rotation, said motor means disposed to turn said drive shaft, a means for governing the rotational speed of said central drive shaft, a circular base cover member connected to said upwardly extending sides of the base, said base cover member combining with the bottom and sides of the base to form said base interior into a sustantially enclosed volume, as said base cover member having an inner circumference defining a central aperture, as id central drive shaft having an upper portion projecting through said central aperture in proximity to said inner circumference, a drive gear position atop said base cover member, said drive gear axially fixed to said upper portion of the central drive shaft, said drive gear having an upper surface having a plurality of upwardly prominent arms, each arm spaced apart from adjacent arms, and a circular tabletop rested atop said arms of said drive gear in a freely removable manner, said tabletop having a substantially planar platform and a plurality of projections extending downwardly from a surface of said tabletop adjoining the arms, a plurality of said projections in rotational transfer engagement with said arms.
Claim 2
Dependent Claim
231 words
A portable microwave oven turntable comprising, a base having a horizontal bottom and upwardly extending sides to form a base interior, a motor means disposed within said base interior, a central drive shaft attached to said base to form a vertical axis of rotation, said motor means disposed to turn said drive shaft, a means for governing the rotational speed of said central drive shaft, a circular base cover member connected to said upwardly extending sides of the base, said base cover member combining with the bottom and sides of the base to form said base interior into a sustantially enclosed volume, as said base cover member having an inner circumference defining a central aperture, as id central drive shaft having an upper portion projecting through said central aperture in proximity to said inner circumference, a drive gear position atop said base cover member, said drive gear axially fixed to said upper portion of the central drive shaft, said drive gear having an upper surface having a plurality of upwardly prominent arms, each arm spaced apart from adjacent arms, and a circular tabletop rested atop said arms of said drive gear in a freely removable manner, said tabletop having a substantially planar platform and a plurality of projections extending downwardly from a surface of said tabletop adjoining the arms, a plurality of said projections in rotational transfer engagement with said arms.
Claim 3
Dependent Claim
28 words
The microwave oven turntable of claim 1 wherein said arms each extend radially outward with respect to said drive gear and wherein said arms have coplanar upper surfaces.
Claim 4
Dependent Claim
47 words
The microwave oven turntable of claim 2 wherein said projections are disposed to form a hub coaxial said central drive shaft, a plurality of said projections extending vertically along a lateral surface of an arm and radially inward along said surface of the tabletop adjoining said arms.
Claim 5
Dependent Claim
17 words
The microwave oven turntable of claim 1 wherein said circular tabletop has a vertical cylindrical side wall.
Claim 6
Dependent Claim
34 words
The microwave oven turntable of claim 1 wherein said means for governing rotational speed includes a gear train having an oscillating governor and having an input gear in meshing relation with said drive gear.
Claim 7
Dependent Claim
19 words
The microwave oven turntable of claim 1 further comprising a braking mechanism for preventing rotation of said drive shaft.
Claim 8
Dependent Claim
181 words
A portable microwave oven turntable comprising, a base assembly having a planar bottom and upwardly extending base sides and having a circular base cover member attached to said base sides to form an enclosed base cavity, said base assembly further having a drive shaft rotatable about a vertical axis and having a motor means for rotating said drive shaft, said motor means disposed within said base cavity, said drive shaft having a portion projecting through the center of said circular base cover member from said base cavity, a drive gear attached to said portion of the drive shaft projecting through said circular base cover member for rotation therewith, said drive gear having a plurality of radial arms having coplanar upper surfaces and opposed lateral surfaces, and a circular tabletop positioned above said drive gear in a freely removable manner, said tabletop having a plurality of teeth releasably engaging said lateral edges of the radial arms for rotation therewith, said table top having a downwardly protruding annular hub coaxial with said central drive shaft, said teeth extending radially inwardly from said hub.
Claim 9
Dependent Claim
181 words
A portable microwave oven turntable comprising, a base assembly having a planar bottom and upwardly extending base sides and having a circular base cover member attached to said base sides to form an enclosed base cavity, said base assembly further having a drive shaft rotatable about a vertical axis and having a motor means for rotating said drive shaft, said motor means disposed within said base cavity, said drive shaft having a portion projecting through the center of said circular base cover member from said base cavity, a drive gear attached to said portion of the drive shaft projecting through said circular base cover member for rotation therewith, said drive gear having a plurality of radial arms having coplanar upper surfaces and opposed lateral surfaces, and a circular tabletop positioned above said drive gear in a freely removable manner, said tabletop having a plurality of teeth releasably engaging said lateral edges of the radial arms for rotation therewith, said table top having a downwardly protruding annular hub coaxial with said central drive shaft, said teeth extending radially inwardly from said hub.
Claim 10
Dependent Claim
23 words
The microwave oven turntable of claim 7 further comprising a gear train means for governing the speed of rotation of the drive shaft.
Claim 11
Dependent Claim
28 words
The microwave oven turntable of claim 8 further comprising a braking mechanism, said braking mechanism selectively locking operation of said gear train means, thereby preventing drive shaft rotation.
Claim 12
Dependent Claim
29 words
The microwave oven turntable of claim 7 further comprising a plurality of freely rotating rollers fixed to said base cover member and in frictional contact with said circular tabletop.
Claim 13
Dependent Claim
43 words
The microwave oven turntable of claim 8 wherein said gear train means includes an input gear atop said base assembly and in meshing engagement with said drive gear, the gear train means further includes a plurality of gears disposed within said base cavity.
Claim 14
Dependent Claim
19 words
The microwave oven turntable of claim 7 wherein said drive gear and said radial arms are an integral member.
Claim 15
Dependent Claim
17 words
The microwave oven turntable of claim 7 wherein said circular tabletop includes a downwardly depending cylindrical sidewall.
Claim 16
Dependent Claim
27 words
The microwave oven turntable of claim 7 wherein said base cover member has a central recessed area and said drive gear is disposed within said recessed area.
References Cited (Backward Citations)
US4036151A
Cited
US4219715A
Cited
US4501945A
Cited
US4523070A
Cited
US4591682A
Cited
US4631379A
Cited
US4590351A
Cited
US4694132A
Cited
US4746781A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-02-28 | 1992-08-29 | 1993-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-28 | 1996-08-29 | 1997-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-28 | 2000-08-29 | 2001-02-28 | $7700.00 | Window Closed / Lapsed |