Vacuum thumper
CA 1189608 A · Owner: Miller, Norvell L. · Inventors: Miller, Norvell L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A variable frequency seismic pulse is produced by releasing a weighted piston within a partially evacuated cylinder. The piston compresses residual air in the cylinder before striking a base plate held firmly in contact with the ground. Controlling the pressure of the gas remaining in the cylinder controls the frequency and amplitude of the seismic pulse applied to the ground. The seismic pulse can be applied at various angles from vertical from a thumper mounted on a vehicle or from a hand-held thumper. -1-
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 June 25, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 25, 2002.
- 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.