Shingle stacking machine
CA 2010784 C · Owner: Benson, Bruce V. · Inventors: Benson, Bruce V.; Siddigi, Ashraf A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A shingle stacking machine including a shingle stacking station, a shingle bundling station and a, conveyor for removing bundled shingles from the machine. The shingle stacking station includes a pair of parallel arid elongated wheel assemblies rotatably mounted to a frame of the machine. A drive mechanism is provided for rotatably indexing each wheel assembly during a drive mode of operation and permits free wheeling of the wheel assemblies during a jam mode of operation. The drive mechanism includes a motor for continuously driving a vacuum operated clutch assembly. The clutch assembly includes a pair of electromagnetic valves for controlling operation of a drive shaft which is connected …
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 February 23, 1990 and granted January 22, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 23, 2012.
- 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.