The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 19, 2001
Filed:
Dec. 10, 1997
W. Daniel Hillis, Toluca Lake, CA (US);
The Long Now Foundation, Sausalito, CA (US);
Abstract
A mechanical device converts one time base to another without using gears to do so. A mechanical adder adds a constant into an accumulator at regular intervals. The interval is generated by the overflow of the accumulator. In the case where a signal is to be generated once every solar year from a wheel that rotates only once per day, the fractional number 1/365.242198 is added to the accumulator each day by the rotation of a day wheel. Whenever the accumulation overflows, the one-year signal is generated. The fractional portion of the accumulated sum remains in the accumulator, such that round-off errors do not accumulate over time. The preferred adder is digital, such that this computation may be carried out to any desired level of precision. Additionally, the same design, but with a different constant, may be used to generate other intervals (e.g. for lunar months).