Abstract: A jack, comprising: a top plate adapted to contact a load; a base plate positioned below the top plate; at least one actuator coupled perpendicularly between the base plate and the top plate; wherein the at least one actuator is operable to move the top plate between a lowered position and a raised position to thereby lower and raise the load; and, at least one locking assembly adapted to lock the top plate in the raised position.

Abstract: A jack, comprising: a top plate having at least one adapter block mounted thereon and adapted to contact a load; an intermediate plate; a base plate; a first pair of actuators coupled between the base and intermediate plates; and, a second pair of actuators coupled between respective lowered portions of the intermediate plate and the top plate; wherein one of the first pair of actuators is positioned on the base plate on either side of the respective lowered portions; wherein the actuators are operable to move the top and intermediate plates between respective lowered and raised positions to thereby lower and raise the load; and, wherein a top adapter plate of the at least one adapter block is operable to slide between first and second positions across the top plate as the load is raised and lowered to maintain alignment of the top, intermediate, and base plates below the load.

Abstract: A jack, comprising: a top plate adapted to contact a load; a base plate positioned below the top plate; at least one actuator coupled perpendicularly between the base plate and the top plate; wherein the at least one actuator is operable to move the top plate between a lowered position and a raised position to thereby lower and raise the load; and, at least one locking assembly adapted to lock the top plate in the raised position.

Abstract: A jack, comprising: a top plate adapted to contact a load; an intermediate plate positioned below the top plate, the intermediate plate having a channel formed therein; a base plate positioned below the intermediate plate; a first pair of actuators coupled between the base plate and the intermediate plate, one of the first pair of actuators positioned on either side of the channel; and, a second pair of actuators coupled between the channel of the intermediate plate and the top plate; wherein the first and second pairs of actuators are operable to move the top plate and the intermediate plate between respective lowered positions and respective raised positions to thereby lower and raise the load.

Abstract: An ore chute system, comprising: a chute box for collecting material and having a chute opening formed therein for discharging the material therethrough; a chute press gate mounted over the chute opening and moveable between an opened position to allow discharge of the material from the chute box and a closed position to prevent discharge of the material from the chute box; a chute press gate actuator coupled to the chute press gate and controllable to move the chute press gate between the opened position and the closed position; and, a chute press gate counterweight system coupled to the chute press gate and configured to move the chute press gate from the opened position to the closed position upon failure of the chute press gate actuator.