Acceleration sensitive flow sensitive mcpherson strut

Abstract

A modified McPherson strut has inner and outer tubes which are connected to the wheel of a vehicle. A piston within the inner tube is connected to a piston rod which is connected to the body of a vehicle. The piston divides the inner tube into an upper chamber and a lower chamber, with the upper chamber being in fluid communication with an annular gallery formed between the inner and outer tubes. Normal damping is provided by fluid passing though metering valves in the piston between the upper and lower chambers. The strut also includes an accumulator gallery inside the bottom of the outer tube with a foot valve for restricted fluid flow from the lower chamber into the accumulator gallery and essentially unrestricted flow from the accumulator gallery back into the lower chamber. An acceleration sensitive inertial mass in a bypass passage is normally closed and opens upon upward acceleration of the tubes during strut compression. This bypasses fluid directly from the lower chamber into the accumulator gallery, making the strut 'softer.' Similarly, a rebound inertial mass in another bypass passage opens a valve when the downward acceleration of the tubes is greater than a selected magnitude. A restricted flow path is provided downstream from the rebound inertial valve opening for maintaining the inertial mass in a port-open position in response to fluid flow past the rebound inertial mass.