Wiper device for stripping fluid from well pipe
CA 1189447 A · Owner: Brown, William H. · Inventors: Brown, William H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
WIPER DEVICE FOR STRIPPING, FLUID FROM WELL PIPE" ABSTRACT OF THE DISCLOSURE, A wiper device is provided comprising a container having a central opening through which the well string may pass. A pair of opposed wiper pads disposed in a horizontal attitude are mounted in spaced vertical relationship within the container for longitudinal movement toward each other, to engage the vertical string. A doubleacting pneumatic cylinder actuates each pad. Each cylinder is mounted in the plane of the pad, said cylinder being connected at its front end with the rear portion of the wiper pad and being pivotally connected at its rear end with a support member. The front end of the cylinder is thus …
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.