HYDRAULIC DAMPERS WITH PRESSURE REGULATED CONTROL VALVE AND SECONDARY PISTON
(19)AUSTRALIAN PATENT OFFICE(54) Title HYDRAULIC DAMPERS WITH PRESSUREREGULATED CONTROL VALVE AND SECONDARYPISTON(21) Application No: 2003232466 (22) Application Date: 2003.05.29(87) WIPONo: WO03/102426 (30) Priority Data (31) Number (32) Date (33) Country60/384,369 2002.05.29US(43) Publication Date : 2003.12.19(43) Publication Journal Date : 2004.02.12(71)Applicant(s)PROGRESSIVE SUSPENSION, INC.(72)Inventor(s) TURNER, Roy, A. (H) Application NoAU2003232466 A1(19)AUSTRALIAN PATENT OFFICE(54) Title HYDRAULIC DAMPERS WITH PRESSUREREGULATED CONTROL VALVE AND SECONDARYPISTON(21) Application No: 2003232466 (22) Application Date: 2003.05.29(87) WIPONo: WO03/102426 (30) Priority Data (31) Number (32) Date (33) Country60/384,369 2002.05.29US(43) Publication Date : 2003.12.19(43) Publication Journal Date : 2004.02.12(71)Applicant(s)PROGRESSIVE SUSPENSION, INC.(72)Inventor(s) TURNER, Roy, A. A suspension damper includes a housing bounding a main chamber. A hydraulic fluid is disposed within the main chamber. A piston rod is selectively movable between an advanced position wherein a portion of the piston rod is advanced into the main chamber and a retracted position wherein the portion of the piston rod is retracted from the main chamber, wherein as the piston rod is moved a fluid pressure of the hydraulic fluid within the main chamber progressively increases and a portion of the hydraulic fluid passes through a passage within the housing. A control valve is at least partially disposed within the main chamber, the control valve being moved by the fluid pressure of the hydraulic fluid so as to progressively restrict the flow of the hydraulic fluid through the passage as the fluid pressure of the hydraulic fluid within the main chamber progressively increases. CLAIMS What is claimed is: 1. A suspension damper comprising: a housing bounding a main chamber extending between a first end and an opposing second end; a piston rod having a first end slideably disposed within the main chamber and an opposing second end disposed outside of the main chamber; a main piston mounted on the first end of the piston rod within the main chamber of the housing so as to slideably engage against the housing in a substantially sealed engagement, the main piston having a first side and an opposing second side with a compression port extending therebetween; a secondary piston disposed within the main chamber at a location between the piston rod and the second end of the main chamber, the secondary piston having a first side and an opposing second side with a compression port extending therebetween;STDC0411 and a control valve assembly mounted on or adjacent to the secondary piston, the control valve assembly bounding a sealed valve compartment, the control valve assembly being moveable between a first position wherein the valve compartment is compressed to a first volume and a second position wherein the valve compartment is expanded to a second volume, the second volume being larger than the first volume.
2. A suspension damper as recited in claim 1, wherein the control valve assembly is disposed such that the control valve assembly substantially blocks the compression port on the secondary piston when the control valve assembly is in the first position and the compression port is substantially unblocked when the control valve assembly is in the second position.
3. A suspension damper as recited in claim 2, wherein the control valve is disposed on the second side of the secondary piston.
4. A suspension damper as recited in claim 3, further comprising: a rebound port extending between the first side and the opposing second side of the secondary piston; and means for enabling fluid flow through the rebound port from the second side to the first side of secondary piston while precluding fluid flow from the first side to the second side of the secondary piston. <Desc/Clms Page number 32> 5. A suspension damper as recited in claim 4, wherein the means for enabling fluid flow comprises a flexible shim mounted on the first side of the main piston so as to cover the rebound port thereat.
6. A suspension damper as recited in claim 1, further comprising a shaft coupling the control valve assembly to the secondary piston.
7. A suspension damper as recited in claim 1, wherein at least a portion of the control valve assembly is secured to or integrally coupled with the secondary piston.
8. A suspension damper as recited in claim 1, wherein the secondary piston is rigidly secured to the housing.
9. A suspension damper as recited in claim 1, wherein the secondary piston is slideably disposed on the housing in sealed engagement therewith.
10. A suspension damper as recited in claim 1, wherein the control valve assembly comprises a control valve slideably disposed on a valve guide, the sealed valve compartment being formed between the control valve and the valve guide.
11. A suspension damper as recited in claim 10, wherein the control valve has a first face and an opposing second face each having a surface area, an aspect ration of the area of the first face to the area of the second face being in a range between about 0.2 to about 0.6.
12. A suspension damper as recited in claim 1, further comprising a rebound channel extending through the piston rod between a first opening formed on the piston rod on one side of the main piston and a second opening formed on the piston rod on an opposing side of the main piston.
13. A suspension damper as recited in claim 12, further comprising a flow regulating pin movably disposed within a least a portion of rebound channel.
14. A suspension damper as recited in claim 13, further comprising means for enabling fluid flow through the rebound channel from the first opening to the second opening while precluding fluid flow from the second opening to the first opening.
15. A suspension damper as recited in claim 14, wherein the means for enabling fluid flow through the rebound channel comprises a flexible shim mounted on the piston rod so as to cover the second opening of the rebound channel.
16. A suspension damper as recited in claim 1, further comprising means for enabling fluid flow through the compression port from the second side to the first <Desc/Clms Page number 33> side of the main piston while precluding fluid flow from the first side to the second side of the main piston.
17. A suspension damper as recited in claim 1, further comprising: a rebound port extending between the first side and the opposing second side of the main piston; and means for enabling fluid flow through the rebound port from the first side to the second side of the main piston while precluding fluid flow from the second side to the first side of the main piston.
18. A suspension damper as recited in claim 17, wherein the means for enabling fluid flow through the rebound port comprises a flexible shim mounted on the second side of the main piston so as to cover the rebound port thereat.
19. A suspension damper as recited in claim 1, wherein the piston rod comprises a rod body having a bolt coupled therewith, the bolt extending through the main piston.
20. A suspension damper as recited in claim 1, further comprising a second control valve assembly mounted on or adjacent to the main piston, the second control valve assembly bounding a sealed valve compartment, the second control valve assembly being moveable between a first position wherein the valve compartment is compressed to a first volume and a second position wherein the valve compartment is expanded to a second volume, the second volume being larger than the first volume.
21. A suspension damper as recited in claim 1, further comprising a hydraulic fluid disposed at the first end of the main chamber and a compressible gas disposed at the second end of the main chamber, the hydraulic fluid being in direct contact with the compressible gas.
22. A suspension damper as recited in claim 1, further comprising a barrier disposed within the main chamber that divides the main chamber into a relative first chamber and a relative second chamber, the barrier preventing the transfer of fluids or gasses between the first chamber and the second chamber but enabling the transfer of a pressure differential between the first chamber and the second chamber, the main piston and the secondary piston each being disposed within the first chamber.
23. A suspension damper as recited in claim 22, wherein the barrier comprises a floating piston.
24. A suspension damper as recited in claim 22, wherein the barrier comprises an inflatable bladder disposed within the main chamber of the housing, the <Desc/Clms Page number 34> bladder bounding the second chamber.
25. A suspension damper as recited in claim 22, wherein the barrier comprises a flexible diaphragm mounted to the housing within the main chamber.
26. A suspension damper as recited in claim 22, wherein the housing comprises: an inner sidewall bounding an inner chamber; and an outer sidewall encircling the inner side wall, an outer chamber being formed between the inner sidewall and outer sidewall in fluid communication with the inner chamber, the combined inner chamber and outer chamber comprising the main chamber.
27. A suspension damper as recited in claim 26, wherein the main piston and the secondary piston are disposed within the inner chamber.
28. A suspension damper as recited in claim 26, wherein the barrier comprises an inflatable bladder disposed within the outer chamber of the housing.
29. A suspension damper as recited in claim 22, wherein the housing comprises : a primary housing bounding a primary chamber; a secondary housing spaced apart from the primary housing, the secondary housing bounding a secondary chamber, the combined primary chamber and secondary chamber comprising the main chamber; and a tubular stem fluid coupling the primary chamber to the secondary chamber.
30. A suspension damper as recited in claim 29, wherein the main piston and the secondary piston are disposed within the primary chamber.
31. A suspension damper as recited in claim 29, wherein the main piston is disposed within the primary chamber and the secondary piston is disposed within the secondary chamber.
32. A suspension damper as recited in claim 29, wherein the barrier is disposed within the secondary chamber of the housing.
33. A suspension damper as recited in claim 29, further comprising gas valve mounted on the secondary housing for selectively putting a gas into or withdrawing a gas from the secondary chamber.
34. A suspension damper as recited in claim 22, wherein the sealed valve compartment of the control valve contains a gas at a first pressure. <Desc/Clms Page number 35> 35. A suspension damper as recited in claim 34, wherein a hydraulic fluid is disposed within the first chamber and a compressible gas is disposed within the second chamber, the gas in the second chamber being at a second pressure that is greater than the first pressure in the valve compartment of the control valve.
36. A suspension damper as recited in claim 22, further comprising means for selectively adjusting the size of the second chamber.
37. A suspension damper as recited in claim 36, wherein the means for selectively adjusting the size of the second chamber comprises an adjustable piston bounding a portion of the second chamber, the adjustable piston being selectively movable into the second chamber so as to effectively decrease the size of the second chamber.
38. A suspension damper as recited in claim 22, further comprising means for selectively putting a gas into or withdrawing a gas from the second chamber.
39. A suspension damper as recited in claim 38, wherein the means for selectively putting a gas into or withdrawing a gas from the second compartment comprises an gas valve in fluid communication with the second chamber.
40. A suspension damper as recited in claim 22, further comprising a spring disposed within the second chamber and biasing against the barrier.
41. A shock absorber comprising the suspension damper as recited in claim 1.
42. A front fork comprising the suspension damper as recited in claim 1.