Die-cushion apparatus of press machine
CA 2094827 C · Owner: Kabushiki Kaisha Komatsu Seisakusho · Inventors: Yoshikawa, Eiji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An object of the present, invention is to provide a die cushion device of a press machine, wherein, preliminary acceleration can be applied to a die cushion pad following the descent of a slide at an accurate, timing and with high accuracy and such improvements can be, achieved that a difference in pressure between a real pressure in a, hydraulic cylinder and a preset target value can be eliminated in the, vicinity of a bottom dead center of a slide stroke. Said die cushion, device comprises an air pressure cylinder (6) and a hydraulic cylinder, (7) having a servo valve (40) for controlling a discharge pressure, and fed with pressure oil through suction, wherein the supply of the, pressure …
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
- Filed November 1, 1991 and granted April 14, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 1, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 1, 2013.
- 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.