Piezoelectric crystal resonator with reduced impedance and sensitivity to change in humidity
CA 1209652 A · Owner: Ohaus Scale Corporation · Inventors: Eernisse, Errol P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus and method for exciting a piezoelectric crystal resonator is disclosed. An electric oscillator is connected to a double ended tuning fork piezoelectric crystal so that it flexurally vibrates in air at its mechanical resonant frequency. A novel electrode pattern connects the oscillator to the crystal such that changes in humidity do not affect the resonant frequency of the crystal. This arrangement is useful in measuring force, such as weight.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted August 12, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 12, 2003.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.