Hydraulic lift for stand-alone coil spring

A hydraulic lift actuator for adjusting a height of a vehicle, comprising:

• a hydraulic cylinder having a tubular wall defining an interior chamber;
• a piston rod extending axially into the interior chamber;
• a piston assembly connected to the piston rod and disposed within the interior chamber;
• a flexible top mount plate configured for attachment to a chassis element of the vehicle, the flexible top mount plate including an upper plate surrounding the piston rod and spaced apart therefrom, a lower plate, and an isolator disposed between the upper plate and the lower plate, wherein the isolator is configured to dampen vibrations, wherein the lower plate further comprises stand-offs configured to engage an upper surface of the spring seat when the spring seat is in the retracted position;
• an inner tube rigidly connected to the lower plate and the piston rod, wherein the inner tube is disposed within the interior chamber, and wherein the inner tube extends axially between the lower plate and the piston assembly;
• and
• a spring seat rigidly connected to the hydraulic cylinder and configured to engage a top end of a coil spring, wherein the spring seat and the hydraulic cylinder are linearly translatable between a retracted position adjacent to the flexible top mount plate and an extended position spaced apart from the flexible top mount plate.

A height adjustment system for adjusting a height of a vehicle, the height adjustment system comprising:

• at least one wheel;
• a first suspension arrangement including:
• a coil spring having an upper end and a lower end coupled to one of the at least one wheel, and
• a hydraulic actuator, the hydraulic actuator including:
• a top mount plate attached to a chassis element of a vehicle;
• a hydraulic cylinder having a tubular wall and an end cap, together defining an interior chamber;
• a piston rod extending axially into the interior chamber;
• a piston assembly connected to the piston rod and disposed within the interior chamber, wherein the piston assembly divides the interior chamber into an upper chamber and a lower chamber, the lower chamber extending between the piston assembly and the end cap;
• a spring seat rigidly connected to the hydraulic cylinder and configured to engage the upper end of the coil spring, wherein the spring seat and the hydraulic cylinder are linearly translatable relative to the piston rod between a retracted position adjacent to the top mount plate and an extended position spaced apart from the top mount plate;
• and
• a controller operatively connected to the hydraulic actuator and configured to control fluid flow into and out of the lower chamber for adjusting the height of the vehicle,
• wherein the top mount plate further comprises an upper plate, a lower plate connected to the piston rod, and an isolator disposed between the upper plate and the lower plate, wherein the lower plate further includes a plurality of stand-offs each configured to engage an upper surface of the spring seat when the spring seat is in the retracted position.