Variable damping system using a piezoelectric device

A damper assembly comprising:

• a housing defining an interior chamber, and extending along a longitudinal axis;
• a rod supported by the housing and at least partially disposed within the interior chamber of the housing;
• a piston assembly attached to the rod within the interior chamber of the housing, and positioned to separate the interior chamber into at least a first fluid chamber and a second fluid chamber, and operable to resist relative movement between the rod and the housing at a damping rate;
• wherein the piston assembly includes an annular plate defining at least one orifice interconnecting the first fluid chamber and the second fluid chamber in fluid communication;
• a piezoelectric device moveable between at least a disengaged position and an engaged position in response to a control signal, wherein the piezoelectric device does not affect fluid flow through the at least one orifice when disposed in the disengaged position, and wherein the piezoelectric device does affect fluid flow through the at least one orifice when disposed in the engaged position to adjust the damping rate of the piston assembly;
• wherein the piston assembly includes at least one valve disc disposed adjacent a face of the annular plate, between the piezoelectric device and the annular plate;
• wherein the at least one valve disk is bendable relative to the rod about a spring point in response to a fluid pressure to control fluid flow through the at least one orifice, between first fluid chamber and the second fluid chamber;
• and
• wherein the piezoelectric device engages the at least one valve disk to move the spring point, about which the at least one valve disk bends, radially outward relative to the longitudinal axis, to change the fluid pressure required to bend the at least one valve disk when the piezoelectric device is disposed in the engaged position.

A damping system comprising:

• a control module operable to generate a control signal;
• a damper assembly coupled to the control module, and including a piezoelectric device operable to move between an engaged position and a disengaged position in response to the control signal;
• wherein the damper assembly includes a housing defining an interior chamber, and a piston assembly disposed within the interior chamber and positioned to separate the interior chamber into a first fluid chamber and a second fluid chamber;
• wherein the piston assembly includes an annular plate defining at least one orifice interconnecting the first fluid chamber and the second fluid chamber in fluid communication;
• a damping fluid disposed within the interior chamber of the housing, and moveable through the at least one orifice between the first fluid chamber and the second fluid chamber;
• wherein the piezoelectric device does not affect fluid flow through the at least one orifice when disposed in the disengaged position,
• wherein the piezoelectric device does affect fluid flow through the at least one orifice when disposed in the engaged position to control a flow of the damping fluid through the at least one orifice and adjust a damping rate of the piston assembly;
• wherein the piston assembly includes at least one valve disc disposed adjacent a face of the annular plate, between the piezoelectric device and the annular plate;
• wherein the at least one valve disk is bendable relative to the rod about a spring point in response to a fluid pressure applied by the damping fluid to control fluid flow through the at least one orifice, between first fluid chamber and the second fluid chamber;
• and
• wherein the piezoelectric device engages the at least one valve disk to move the spring point, about which the at least one valve disk bends, radially outward relative to a longitudinal axis, to change the fluid pressure required to bend the at least one valve disk when the piezoelectric device is disposed in the engaged position.