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US3574995A Expired / Lapsed US ⏱️ 0.0 years remaining

Digital timekeeping device with improved indexing mechanism

Assignee: GENERAL TIME INSTRUMENTS Inc A CORP OF DE
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Filing: 1969-10-08
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Granted: 1971-04-13
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Expires: 1989-10-08
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Abstract

Abstract A time-keeping device providing digital visual indication of the time. Indexing means are provided to permit digital visual indication of the time in terms of full integers. The indexing means utilized includes a cam wheel and an index wheel, the camming surfaces of the cam wheel being sloped in reverse of the ratchet teeth of the index wheel. A pawl is provided to engage the ratchet teeth of the index wheel until released by the camming surfaces of the cam wheel whereupon the index wheel rotates as a result of being continuously urged to rotate in the same direction as the cam wheel. The rotation of the index wheel is limited to a predetermined angular amount by means acting between the two wheels. Means are provided for permitting setting and adjustment of the indexing mechanism in order to cause the indicating means to permit visual observation of the correct time.

Inventors

  • 👤 Vernon P Turner

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 09:19
CPC Classifications
G; G04; G04B; G04B19/00; G04B19/20; G04B19/21; G06; G06M; G06M1/00; G06M1/04; G06M1/041; G06M1/042

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 222 words
A time-keeping device comprising the combination of indicating means for providing digital visual indication of the time, indexing means for operating said indication means and drive means for operating said index means, said indexing means comprising the combination of a cam wheel having a plurality of sloped camming surfaces and being operatively connected to said drive means for rotation at a predetermined angular rate, an index wheel rotating about the same axis as the cam wheel and having a plurality of ratchet teeth sloped in a direction reverse of the camming surfaces of the cam wheel, means acting between the cam wheel and the index wheel for continuously urging the index wheel to rotate in the same direction as the cam wheel, means engaging both wheels providing restraint of the index wheel until the cam wheel has undergone a predetermined angular rotation and thereafter releasing said index wheel permitting said index wheel to rotate, control means acting between the cam wheel and the index wheel and independent of said restraining means to limit the rotation of said index wheel upon its release to the said predetermined angular rotation of the cam wheel, means for selective adjustment of the cam and index wheels for selecting the desired initial positions of said wheels, and means operatively connecting said index wheel to said indicating means.
Claim 2
Dependent Claim 222 words
A time-keeping device comprising the combination of indicating means for providing digital visual indication of the time, indexing means for operating said indication means and drive means for operating said index means, said indexing means comprising the combination of a cam wheel having a plurality of sloped camming surfaces and being operatively connected to said drive means for rotation at a predetermined angular rate, an index wheel rotating about the same axis as the cam wheel and having a plurality of ratchet teeth sloped in a direction reverse of the camming surfaces of the cam wheel, means acting between the cam wheel and the index wheel for continuously urging the index wheel to rotate in the same direction as the cam wheel, means engaging both wheels providing restraint of the index wheel until the cam wheel has undergone a predetermined angular rotation and thereafter releasing said index wheel permitting said index wheel to rotate, control means acting between the cam wheel and the index wheel and independent of said restraining means to limit the rotation of said index wheel upon its release to the said predetermined angular rotation of the cam wheel, means for selective adjustment of the cam and index wheels for selecting the desired initial positions of said wheels, and means operatively connecting said index wheel to said indicating means.
Claim 3
Dependent Claim 52 words
A time-keeping device as set forth in claim 1 wherein said means for continuously urging the index wheel to rotate comprises a spring freely encircling part of the interior portions of said wheels, said spring having one end attached to said cam wheel and the other end attached to said index wheel.
Claim 4
Dependent Claim 62 words
A time-keeping device as set forth in claim 1 wherein said means providing restraint of said index wheel comprises a spring-loaded pawl engaging the ratchet teeth of said index wheel, said pawl being moved out of engagement with said ratchet teeth of said index wheel by rotation of the camming surfaces of said cam wheel, thereby permitting said index wheel to rotate.
Claim 5
Dependent Claim 80 words
A time-keeping device as set forth in claim 1 wherein said means acting between the cam wheel and the index wheel limiting the rotation of said index wheel comprises at least one circumferential slot, said slot being disposed inwardly from the outeR periphery of one of said wheels, and a lug, said lug having one end attached to the other of said wheels and the other end disposed within said slot to limit the relative angular displacement of said wheels.
Claim 6
Dependent Claim 56 words
A time-keeping device as set forth in claim 1 wherein said means for selective adjustment of the cam and index wheels includes a manually engageable and manually rotatable pinion, gears communicating said pinion with said cam wheel, and means activated by engagement of said pinion for displacing said cam wheel drive means from said cam wheel.
Claim 7
Dependent Claim 220 words
A time-keeping device comprising the combination of indicating means for providing digital visual indication of the time, indexing means for operating said indicating means and drive means for operating said indexing means, said indexing means comprising the combination of of a cam wheel having a plurality of sloped camming surfaces and rotating about an axis, said cam wheel being operatively connected to said drive means for rotation at a predetermined angular rate, an index wheel rotating about the same axis as the cam wheel and having a plurality of ratchet teeth sloped in a direction reverse of the camming surfaces of the cam wheel, means acting between the cam wheel and the index wheel for continuously urging the index wheel to rotate in the same direction as the cam wheel, means engaging both wheels providing restraint of the index wheel until the cam wheel has undergone a predetermined angular rotation and thereafter releasing said index wheel permitting said index wheel to rotate, control means attached to one of said wheels and acting on the other of said wheels to limit the rotation of said index wheel upon its release to the said predetermined angular rotation of the cam wheel, means for selective adjustment of the cam and index wheels, and means operatively connecting said index wheel to said indicating means.
Claim 8
Dependent Claim 220 words
A time-keeping device comprising the combination of indicating means for providing digital visual indication of the time, indexing means for operating said indicating means and drive means for operating said indexing means, said indexing means comprising the combination of of a cam wheel having a plurality of sloped camming surfaces and rotating about an axis, said cam wheel being operatively connected to said drive means for rotation at a predetermined angular rate, an index wheel rotating about the same axis as the cam wheel and having a plurality of ratchet teeth sloped in a direction reverse of the camming surfaces of the cam wheel, means acting between the cam wheel and the index wheel for continuously urging the index wheel to rotate in the same direction as the cam wheel, means engaging both wheels providing restraint of the index wheel until the cam wheel has undergone a predetermined angular rotation and thereafter releasing said index wheel permitting said index wheel to rotate, control means attached to one of said wheels and acting on the other of said wheels to limit the rotation of said index wheel upon its release to the said predetermined angular rotation of the cam wheel, means for selective adjustment of the cam and index wheels, and means operatively connecting said index wheel to said indicating means.

References Cited (Backward Citations)

US521001A Cited
US2102533A Cited
US2596370A Cited
US3279166A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-04-12 1974-10-12 1975-04-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-04-12 1978-10-12 1979-04-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-04-12 1982-10-12 1983-04-13 $7700.00 Window Closed / Lapsed

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