Hydraulic jack with a system for checking the position of the piston
CA 1287342 C · Owner: Gratzmuller, Claude Alain · Inventors: Gratzmuller, Claude Alain
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In order to check the operation of highvoltage electric circuit-breakers, proximity detectors are housed in through-bores pierced in the wall of the hydraulic jack cylinder, the through-bores being disposed in spaced relation over a distance corresponding to the range of travel of the jack piston. Since no provision is made fox any piston ring or packing seal the jack piston is not damaged as it passes against the outlets of the through-bores on the internal surface of the cylinder. The output signals of the proximity detectors are applied to a unit for measuring and controlling the position of the piston within the cylinder.
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 6, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 6, 2008.
- 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.