Monotube piston valving system with selective bleed
View Patent ↗A shock absorber piston assembly includes a piston having a first face, a second face and a plurality of fluid passages. Preloaded flow control devices each seal at least one of the fluid passages, including: a first bleed plate contacting the first face and a second bleed plate contacting the second face; and a pair of blow-off discs, with a first blow-off disc contacting the first face and a second blow-off disc contacting the second face. Each of the flow control devices opens at an individually adjustable device opening pressure. Each of the multiple passages in contact with the blow-off discs can also differ in flow area to permit the blow-off discs to angularly lift to limit disc chatter.
1. A shock absorber piston assembly, comprising:
a piston having a first face and an opposed second face, the piston defining a plurality of separate fluid passages allowing fluid communication through only the piston between the first face and the second face;
a piston rod attached to the piston; and
a plurality of flow control devices each operably sealing at least one of the fluid passages, including:
a first bleed plate operably contacting the first face and a second bleed plate operably contacting the second face;
a first blow-off disc operably contacting the first face and a second blow-off disc operably contacting the second face; and
a compression device operably maintaining each of the flow control devices in a closed position in contact with the piston; wherein
each of the flow control devices operably opens at an individually adjustable device opening pressure; and
the compression device comprises a spring; wherein the spring comprises:
a spring engagement end fixedly engaged with a slot of the piston rod; and
a spring force distribution end in contact with the first bleed plate.
2. The piston assembly of claim 1 , wherein the compression device comprises at least one spring disc plate operably maintaining contact between each of the blow-off discs and the piston.
3. The piston assembly of claim 2 , further comprising a preload spacer connectably affixed to the piston rod and operably preloading the at least one spring disc plate.
4. The piston assembly of claim 3 , further comprising an interface disc located between the at least one spring disc plate and each of the blow-off discs.
5. A shock absorber, comprising:
a piston tube;
a piston assembly slidably disposed within the piston tube and operably dividing the piston tube into a first working chamber and a second working chamber, the piston assembly including:
(i) a piston having a first face and an opposed second face, the piston defining a plurality of separate fluid passages allowing fluid communication through only the piston between the first face and the second face; and
(ii) a plurality of flow control devices each operably sealing at least one of the fluid passages, including:
(a) a first bleed plate operably contacting the first face and a second bleed plate operably contacting the second face; and
(b) a first blow-off disc operably contacting the first face and a second blow-off disc operably contacting the second face;
a piston rod fastenably attached to the piston assembly; and
a compression device operably maintaining each of the flow control devices in a closed position in contact with the piston; wherein
each of the flow control devices operably opens at an individually adjustable device opening pressure; and
the compression device comprises a spring; wherein the spring comprises:
a spring engagement end fixedly engaged with a slot of the piston rod; and
a spring force distribution end in contact with the first bleed plate.
6. The shock absorber of claim 5 , wherein the piston tube comprises, a first end fitting connectable to an axle assembly of an automobile vehicle.
7. The shock absorber of claim 6 , further comprising:
a second end fitting fixedly connectable to the piston rod and operably connecting the shock absorber to a vehicle body of an automobile vehicle.