US 6,981,578 B2
Non-pressurized monotube shock absorber
Troy Leiphart, 30777 Highway 40, New Auburn, Wis. 54757 (US); and James D. Hansen, W. 9362 Woodlawn Dr., Holcombe, Wis. 54745 (US)
Filed on Jul. 16, 2004, as Appl. No. 10/893,041.
Claims priority of provisional application 60/491303, filed on Jul. 31, 2003.
Prior Publication US 2005/0023093 A1, Feb. 03, 2005
Int. Cl. F16F 9/34 (2006.01); F16K 15/16 (2006.01)
U.S. Cl. 188—322.14 15 Claims
OG exemplary drawing
 
1. A non-pressurized monotube hydraulic damper device comprising;
a hollow, cylindrical tube body having a first end and a second end, with a rod guide member fixed at the first end of the tube body and a base member fixed at the second end of the tube body;
a piston and rod assembly including a linear rod member passing slidingly and sealably through the rod guide member and secured at one end to a piston member slidingly and sealably positioned interior the tube body, the piston member dividing the tube body into a rebound chamber adjacent the rod guide member and a compression chamber adjacent the base member, the piston member including valving for fluid flow between the compression chamber and the rebound chamber;
a base valve member mechanically fixed at the second of the tube body between the piston member and the base member, the base valve member dividing the compression chamber into a third chamber adjacent the base member, the base valve member regulating fluid flow between the compression chamber and the third chamber, the base valve member comprising a deflective disk assembly including a replenishing valve member atop a valve plate member positioned on a metering valve member, the valve plate member containing a central replenishing passage in register with a similar replenishing passage in the metering valve member, the replenishing valve member containing a replenishing flapper portion covering the central replenishing passage of the valve plate member, the valve plate member containing a plurality of metering passages offset and fluidly disconnected from the central replenishing passage of the valve plate member, the metering passages unobstructed on one side by the replenishing valve member and covered on another side by the metering valve member such that during a compression stroke fluid flow through the central replenishing passage of the valve plate member is prevented by the flapper portion of the replenishing valve member covering the central replenishing passage of the valve plate member; and
a compressible member within the third chamber, the compressible member exerting essentially atmospheric pressure in an expanded condition.