Precast concrete manhole adjustable bolt slot for securing cast iron frame and cover and method for casting same
CA 1270139 C · Owner: Ditcher, Jack · Inventors: Ditcher, Jack
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An insert is provided herein for use as an adjustable fastener slot in manhole top sections and the like for mounting and securing a cover frame thereto. The insert includes an elongated plastic member having a hollow interior of a substantially-T-shaped-cross-section defining a wide base portion and a narrow upper portion. The exterior periphery of the insert generally conforms to that cross-sectional configuration. The top surface of the insert is formed of an integral web of a thickness which is substantially less than the thickness of the remaining portion of the web body to facilitate the cutting away and removal of the web for insertion of a threaded member. The enlarged base portion …
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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 12, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 12, 2007.
- 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.