Patent ID: 7438506
Filing Date: 2008-10-21
Classification: E21F

Abstract:
1. A jack for installing in a mine a plurality of elongate extensible panels adapted to extend in side-by-side relation, each panel comprising a lower panel member of the panel and an upper member of the panel, each of said lower and upper panel members of a panel being a sheet metal member having a web and first and second flanges along opposite sides of the web, one of said panel members having a telescoping sliding fit relative to the other panel member with the webs of the panel members generally face-to-face, the upper panel member of each panel having an end piece at its upper end and the lower panel member of each panel having an end piece at its lower end, said jack comprising: a base adapted to engage a first end piece of one of the upper and lower panel members; a guide extending from the base; an extensible member having an extensible fit with the guide and extending from the guide to have a free end; a support at the free end of the extensible member adapted to engage a second end piece of the upper and lower panel members; and an actuator for extending the extensible member to move the support into pressure engagement with the second end piece; said guide and extensible member having portions which are laterally offset with respect to said base and said support such that when the support is in pressure engagement with the second end piece, said laterally offset portions are disposed adjacent one side of the panel to leave an area between opposite sides of the panel substantially unobstructed.