Patent ID: 7416459

Claim:
A jack plate/hydraulic cylinder system for the vertical adjustable coupling of an outboard motor with respect to a boat in a safe, secure and economical manner comprising, in combination: a laterally extending fixed transom bat fixedly positioned at the rear of a boat; a jack plate adjustably positioned at the rear of a boat and adapted to support an outboard motor; a hydraulic cylinder adjustably coupled above to the jack plate and below to the fixed transom bar, the hydraulic cylinder including a hollow cylindrical housing with an upper end and a lower end and a cylindrical chamber there within, a bottom cap having an upper end positioned within the lower end of the housing and a lower end with a flat face and a bolt securing the bottom cap to the fixed transom bar, a top cap having a lower end positioned within the upper end of the housing and an upper end exterior of the housing, a lower split ring securing the bottom cap to the housing and an upper split ring securing the top cap to the housing, the hydraulic cylinder also including a cylindrical piston axially slidable within the housing between the top and bottom caps, the piston including a rod with a bottom end coupled to the piston and an upper end coupled to the jack plate with a clevis and bolt between the rod and the jack plate, the rod having a central extent with a bore through the upper cap for the passage of the rod; and a fluid handling assembly including a lower recess formed in the lower cap facing the piston and an upper recess formed in the upper cap facing the piston with a lower port extending through the housing adjacent to the lower end and into the lower recess and an upper port extending through the housing adjacent to the upper end and into the upper recess, the fluid handling assembly including a pair of annular recesses in the piston with an o-ring and a rectangular ring within each recess, a pair of annular recesses in the lower cap spanning the lower port with an o-ring and a rectangular ring within each recess, a pair of annular recesses in the upper cap spanning the upper port with o-rings and a rectangular ring within each recess, the rectangular rings being fabricated of nitrile 90 durometer packing rings, a single annular recesses in the upper end of the upper cap facing the rod with three o-rings within the recess, an annular recess adjacent each end of the cylinder with an o-ring between an associated end and split ring, the lower port adapted to input hydraulic fluid for raising the piston and jack plate while the upper port is outputting hydraulic fluid, the upper port adapted to input hydraulic fluid for lowering the piston and jack plate while the lower port is outputting hydraulic fluid.