Patent US3673789A successfully refreshed from Google Patents.
US3673789A
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US
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Calendar timepiece with month advancement mechanism for 29,30,or 31 day months
Assignee: Citizen Watch Co Ltd
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Filing: 1971-06-11
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Granted: 1972-07-04
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Expires: 1991-06-11
Abstract
Abstract A calendar watch comprising a date calendar display dial, a month calendar display dial and a date feed wheel, all being rotatably mounted on the movement of said watch, said wheel being driven by said movement for performing a complete revolution per 24 hours, said watch being characterized by that a spring-loaded pawl means for performing an automatic month end date feed operation to said date display dial is pivotably mounted on said wheel.
Inventors
- 👤 Akira Tsuzuki
- 👤 Choken Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:20
CPC Classifications
G; G04; G04B; G04B19/00; G04B19/24; G04B19/243; G04B19/247; G04B19/253; G04B19/25333; G04B19/25353; G04B19/2536
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
191 words
A calendar feed mechanism for a watch movement, comprising in combination of: a date calendar display dial rotatably mounted on said watch movement; a series of 31 date calendar symbols carried on said dial; a series of feeding teeth formed on said dial and in correspondence to said date calendar symbols; a month end feed projection formed on said dial; a month calendar display dial rotatably mounted on said movement, said month dial being adapted for making partial rotation of a step for a complete revolution of said date dial; a series of month calendar symbols covering at least a year and carried on said month dial; a month discriminator cam made integral therewith; a date feed wheel for making a complete revolution for 24 hours by being driven by said movement; and a day feed pawl means pivotably mounted on said date feed wheel; said day feed pawl means being controlled by said discriminator cam and adapted for advancing said date dial daily by a date calendar step and engaging said projection at each end of a 29, 30, or 31 day month to advance the month calendar display dial.
Claim 2
Dependent Claim
191 words
A calendar feed mechanism for a watch movement, comprising in combination of: a date calendar display dial rotatably mounted on said watch movement; a series of 31 date calendar symbols carried on said dial; a series of feeding teeth formed on said dial and in correspondence to said date calendar symbols; a month end feed projection formed on said dial; a month calendar display dial rotatably mounted on said movement, said month dial being adapted for making partial rotation of a step for a complete revolution of said date dial; a series of month calendar symbols covering at least a year and carried on said month dial; a month discriminator cam made integral therewith; a date feed wheel for making a complete revolution for 24 hours by being driven by said movement; and a day feed pawl means pivotably mounted on said date feed wheel; said day feed pawl means being controlled by said discriminator cam and adapted for advancing said date dial daily by a date calendar step and engaging said projection at each end of a 29, 30, or 31 day month to advance the month calendar display dial.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |