External bypass apparatus for vehicle shock absorbers

1 . An external bypass apparatus for a vehicle shock absorber, the shock absorber comprising a substantially cylindrical shock housing within which a shock piston is positioned, the shock piston dividing the shock housing into a first fluid chamber positioned at a first end of the shock housing and a second fluid chamber positioned at an opposing second end of the shock housing, the apparatus comprising:

an at least one compression bypass assembly external to and in fluid communication with the shock housing, the at least one compression bypass assembly comprising:

a compression bypass tube positioned in line between the first fluid chamber and second fluid chamber of the shock housing for allowing a volume of shock fluid within the first fluid chamber to bypass the shock piston as the shock piston moves into a compressed position;

a non-circular-shaped compression bypass port positioned within a housing wall of the shock housing, in line between the first fluid chamber of the shock housing and the compression bypass tube, for establishing fluid communication therebetween; and

a one-way compression bypass valve positioned in line between the compression bypass tube and the second fluid chamber for selectively regulating a flow rate of the shock fluid passing through the compression bypass tube into the second fluid chamber, the compression bypass valve comprising:

a valve body providing an inlet port in fluid communication with the compression bypass tube and an outlet port in fluid communication with the second fluid chamber of the shock housing;

a hollow, substantially cylindrical spool slidably positioned within the valve body, an open end of the spool in fluid communication with the inlet port, with a circumferential sidewall of the spool providing an at least one spool aperture positioned and configured for temporarily allowing the shock fluid to flow radially therethrough, the spool configured for slidably moving within the valve body between an open position—wherein the at least one spool aperture is substantially aligned with the outlet port, thereby allowing the shock fluid to flow from the inlet port, axially through the open end of the hollow spool, radially through the spool aperture, and subsequently through the outlet port—and a closed position—wherein the at least one spool aperture is not aligned with the outlet port, such that the sidewall of the spool obstructs the outlet port and prevents the shock fluid from flowing therethrough;

a return spring positioned within the valve body and configured for biasing the spool into the closed position; and

an adjustment stopper mechanically engaged with the valve body and in mechanical communication with the return spring for allowing a spring force of the return spring to be selectively manually adjusted which, in turn, adjusts an amount of axial overlap between the at least one spool aperture and the outlet port when the spool is in the open position.

2 . The external bypass apparatus of claim 1 , further comprising an at least one rebound bypass assembly external to and in fluid communication with the shock housing, the at least one rebound bypass assembly comprising:

a rebound bypass tube positioned in line between the second fluid chamber and first fluid chamber of the shock housing for allowing a volume of shock fluid within the second fluid chamber to bypass the shock piston as the shock piston moves into a rebound position;

a non-circular-shaped rebound bypass port positioned within the housing wall of the shock housing, in line between the second fluid chamber of the shock housing and the rebound bypass tube, for establishing fluid communication therebetween; and

a one-way rebound bypass valve positioned in line between the rebound bypass tube and the first fluid chamber for selectively regulating a flow rate of the shock fluid passing through the rebound bypass tube into the first fluid chamber, the rebound bypass valve comprising:

a valve body providing an inlet port in fluid communication with the rebound bypass tube and an outlet port in fluid communication with the first fluid chamber of the shock housing;

a hollow, substantially cylindrical spool slidably positioned within the valve body, an open end of the spool in fluid communication with the inlet port, with a circumferential sidewall of the spool providing an at least one spool aperture positioned and configured for temporarily allowing the shock fluid to flow radially therethrough, the spool configured for slidably moving within the valve body between an open position—wherein the at least one spool aperture is substantially aligned with the outlet port, thereby allowing the shock fluid to flow from the inlet port, axially through the open end of the hollow spool, radially through the spool aperture, and subsequently through the outlet port—and a closed position—wherein the at least one spool aperture is not aligned with the outlet port, such that the sidewall of the spool obstructs the outlet port and prevents the shock fluid from flowing therethrough;

a return spring positioned within the valve body and configured for biasing the spool into the closed position; and

an adjustment stopper mechanically engaged with the valve body and in mechanical communication with the return spring for allowing a spring force of the return spring to be selectively manually adjusted which, in turn, adjusts an amount of axial overlap between the at least one spool aperture and the outlet port when the spool is in the open position.

3 . The external bypass apparatus of claim 2 , wherein the rebound bypass port of the at least one rebound bypass assembly is positioned at a height relative to the housing wall of the shock housing that is above an at least one wear ring of the shock piston when the shock piston is in the rebound position.

4 . The external bypass apparatus of claim 2 , wherein the rebound bypass port of the at least one rebound bypass assembly provides a port bridge spanning the rebound bypass port and having a width that is less than a width of the rebound bypass port itself, such that the port bridge is capable of providing a supporting surface over which an at least one wear ring of the shock piston may travel as the shock piston moves between the compressed position and rebound position, while the rebound bypass port remains substantially unobstructed for allowing shock fluid to pass therethrough.

5 . The external bypass apparatus of claim 2 , wherein the rebound bypass valve of the at least one rebound bypass assembly is a pilot-operated valve, whereby an axial position and flow rate of the rebound bypass valve is a function of a pressure differential across the rebound bypass valve.

6 . The external bypass apparatus of claim 2 , wherein:

the compression bypass port of the at least one compression bypass assembly is secured to an outer surface of the housing wall of the shock housing;

the compression bypass valve of the at least one compression bypass assembly is positioned within a valve holder that is secured to the outer surface of the housing wall of the shock housing; and

the compression bypass tube of the at least one compression bypass assembly is engaged with each of the compression bypass port and the valve holder.

7 . The external bypass apparatus of claim 6 , wherein the compression bypass tube of the at least one compression bypass assembly is held captive between each of the compression bypass port and the valve holder by the inserted compression bypass valve into the valve holder.

8 . The external bypass apparatus of claim 6 , wherein one or both of the compression bypass port and valve holder of the at least one compression bypass assembly is secured to the outer surface of the housing wall of the shock housing using a non-permanent attachment mechanism.

9 . The external bypass apparatus of claim 6 , wherein:

the compression bypass tube and compression bypass valve of the at least one compression bypass assembly are positioned within an outer bypass tube;

the outer bypass tube is mechanically engaged with the valve holder; and

the compression bypass port of the at least one compression bypass assembly is engaged with the housing wall of the shock housing via an O-ring slip fit connection.

10 . The external bypass apparatus of claim 1 , wherein the compression bypass port of the at least one compression bypass assembly is positioned at a height relative to the housing wall of the shock housing that is below an at least one wear ring of the shock piston when the shock piston is in the compressed position.

11 . The external bypass apparatus of claim 1 , wherein the compression bypass port of the at least one compression bypass assembly provides a port bridge spanning the compression bypass port and having a width that is less than a width of the compression bypass port itself, such that the port bridge is capable of providing a supporting surface over which an at least one wear ring of the shock piston may travel as the shock piston moves between the compressed position and rebound position, while the compression bypass port remains substantially unobstructed for allowing shock fluid to pass therethrough.

12 . The external bypass apparatus of claim 1 , wherein the compression bypass valve of the at least one compression bypass assembly is a pilot-operated valve, whereby an axial position and flow rate of the compression bypass valve is a function of a pressure differential across the compression bypass valve.

13 . The external bypass apparatus of claim 1 , wherein the at least one compression bypass assembly is permanently secured to an outer surface of the housing wall of the shock housing.

14 . The external bypass apparatus of claim 1 , wherein:

the compression bypass port of the at least one compression bypass assembly is secured to an outer surface of the housing wall of the shock housing;

the compression bypass valve of the at least one compression bypass assembly is positioned within a valve holder that is secured to the outer surface of the housing wall of the shock housing; and

the compression bypass tube of the at least one compression bypass assembly is engaged with each of the compression bypass port and the valve holder.

15 . The external bypass apparatus of claim 14 , wherein the compression bypass tube of the at least one compression bypass assembly is held captive between each of the compression bypass port and the valve holder by the inserted compression bypass valve into the valve holder.

16 . The external bypass apparatus of claim 14 , wherein one or both of the compression bypass port and valve holder of the at least one compression bypass assembly is secured to the outer surface of the housing wall of the shock housing using a non-permanent attachment mechanism.

17 . The external bypass apparatus of claim 14 , wherein:

the compression bypass tube and compression bypass valve of the at least one compression bypass assembly are positioned within an outer bypass tube;

the outer bypass tube is mechanically engaged with the valve holder; and

the compression bypass port of the at least one compression bypass assembly is engaged with the housing wall of the shock housing via an O-ring slip fit connection.

18 . The external bypass apparatus of claim 1 , further comprising a remote reservoir comprising:

a substantially cylindrical reservoir housing within which an internal floating reservoir piston is positioned, the reservoir piston dividing the reservoir housing into a first reservoir chamber positioned at a first end of the reservoir housing and a second reservoir chamber positioned at an opposing second end of the reservoir housing, such that a first end of the reservoir piston is positioned within the first reservoir chamber while an opposing second end of the reservoir piston is positioned within the second reservoir chamber;

the first reservoir chamber containing a volume of a shock gas;

the second reservoir chamber in fluid communication with the second fluid chamber of the shock housing via a reservoir tube, with a reservoir end of the reservoir tube positioned within the second reservoir chamber of the remote reservoir and an opposing shock end of the reservoir tube positioned within the second fluid chamber of the shock housing;

the reservoir end of the reservoir tube providing an eductor nozzle configured for introducing a volume of shock fluid from the second fluid chamber of the shock housing into the second reservoir chamber of the remote reservoir using the Venturi effect when the shock piston moves from a rebound position into the compressed position, the eductor nozzle comprising:

a converging first eductor end positioned proximal to the reservoir end of the reservoir tube;

a diverging second eductor end positioned distal to the reservoir end of the reservoir tube;

a constricted throat portion positioned between the first eductor end and second eductor end; and

an eductor base positioned between the first eductor end and the reservoir end of the reservoir tube, the eductor base providing an at least one eductor aperture positioned on a sidewall of the eductor base;

the second end of the reservoir housing providing a substantially concave eductor surface, with the eductor nozzle extending substantially perpendicularly from a center of the concave eductor surface;

the second end of the reservoir piston providing a substantially concave piston surface, substantially longitudinally opposing the concave eductor surface, with a protrusion extending substantially perpendicularly from a center of the concave piston surface, such that the protrusion is substantially axially aligned with the second eductor end of the eductor nozzle;

whereby, when the shock piston moves from the rebound position into the compressed position, shock fluid ejects through the second eductor end of the eductor nozzle, creating a low-pressure area around the at least one eductor aperture, which promotes shock fluid circulation within the second reservoir chamber and improves cooling efficiency of the shock fluid and, in turn, the shock housing.

19 . An external bypass apparatus for a vehicle shock absorber, the shock absorber comprising a substantially cylindrical shock housing within which a shock piston is positioned, the shock piston dividing the shock housing into a first fluid chamber positioned at a first end of the shock housing and a second fluid chamber positioned at an opposing second end of the shock housing, the apparatus comprising:

a substantially cylindrical reservoir housing within which an internal floating reservoir piston is positioned, the reservoir piston dividing the reservoir housing into a first reservoir chamber positioned at a first end of the reservoir housing and a second reservoir chamber positioned at an opposing second end of the reservoir housing, such that a first end of the reservoir piston is positioned within the first reservoir chamber while an opposing second end of the reservoir piston is positioned within the second reservoir chamber;

the first reservoir chamber containing a volume of a shock gas;

the second reservoir chamber in fluid communication with the second fluid chamber of the shock housing via a reservoir tube, with a reservoir end of the reservoir tube positioned within the second reservoir chamber of the remote reservoir and an opposing shock end of the reservoir tube positioned within the second fluid chamber of the shock housing;

the reservoir end of the reservoir tube providing an eductor nozzle configured for introducing a volume of shock fluid from the second fluid chamber of the shock housing into the second reservoir chamber of the remote reservoir using the Venturi effect when the shock piston moves from a rebound position into the compressed position, the eductor nozzle comprising:

a converging first eductor end positioned proximal to the reservoir end of the reservoir tube;

a diverging second eductor end positioned distal to the reservoir end of the reservoir tube;

a constricted throat portion positioned between the first eductor end and second eductor end; and

an eductor base positioned between the first eductor end and the reservoir end of the reservoir tube, the eductor base providing an at least one eductor aperture positioned on a sidewall of the eductor base;

the second end of the reservoir housing providing a substantially concave eductor surface, with the eductor nozzle extending substantially perpendicularly from a center of the concave eductor surface;

the second end of the reservoir piston providing a substantially concave piston surface, substantially longitudinally opposing the concave eductor surface, with a protrusion extending substantially perpendicularly from a center of the concave piston surface, such that the protrusion is substantially axially aligned with the second eductor end of the eductor nozzle;

whereby, when the shock piston moves from the rebound position into the compressed position, shock fluid ejects through the second eductor end of the eductor nozzle, creating a low-pressure area around the at least one eductor aperture, which promotes shock fluid circulation within the second reservoir chamber and improves cooling efficiency of the shock fluid and, in turn, the shock housing.

20 . An external bypass apparatus for a vehicle shock absorber, the shock absorber comprising a substantially cylindrical shock housing within which a shock piston is positioned, the shock piston dividing the shock housing into a first fluid chamber positioned at a first end of the shock housing and a second fluid chamber positioned at an opposing second end of the shock housing, the apparatus comprising:

an at least one compression bypass assembly external to and in fluid communication with the shock housing, the at least one compression bypass assembly comprising:

a compression bypass tube positioned in line between the first fluid chamber and second fluid chamber of the shock housing for allowing a volume of shock fluid within the first fluid chamber to bypass the shock piston as the shock piston moves into a compressed position;

a non-circular-shaped compression bypass port positioned within a housing wall of the shock housing, in line between the first fluid chamber of the shock housing and the compression bypass tube, for establishing fluid communication therebetween; and

a one-way compression bypass valve positioned in line between the compression bypass tube and the second fluid chamber for selectively regulating a flow rate of the shock fluid passing through the compression bypass tube into the second fluid chamber, the compression bypass valve comprising:

a valve body providing an inlet port in fluid communication with the compression bypass tube and an outlet port in fluid communication with the second fluid chamber of the shock housing;

a hollow, substantially cylindrical spool slidably positioned within the valve body, an open end of the spool in fluid communication with the inlet port, with a circumferential sidewall of the spool providing an at least one spool aperture positioned and configured for temporarily allowing the shock fluid to flow radially therethrough, the spool configured for slidably moving within the valve body between an open position—wherein the at least one spool aperture is substantially aligned with the outlet port, thereby allowing the shock fluid to flow from the inlet port, axially through the open end of the hollow spool, radially through the spool aperture, and subsequently through the outlet port—and a closed position—wherein the at least one spool aperture is not aligned with the outlet port, such that the sidewall of the spool obstructs the outlet port and prevents the shock fluid from flowing therethrough;

a return spring positioned within the valve body and configured for biasing the spool into the closed position; and

an adjustment stopper mechanically engaged with the valve body and in mechanical communication with the return spring for allowing a spring force of the return spring to be selectively manually adjusted which, in turn, adjusts an amount of axial overlap between the at least one spool aperture and the outlet port when the spool is in the open position; and

a substantially cylindrical reservoir housing within which an internal floating reservoir piston is positioned, the reservoir piston dividing the reservoir housing into a first reservoir chamber positioned at a first end of the reservoir housing and a second reservoir chamber positioned at an opposing second end of the reservoir housing, such that a first end of the reservoir piston is positioned within the first reservoir chamber while an opposing second end of the reservoir piston is positioned within the second reservoir chamber;

the first reservoir chamber containing a volume of a shock gas;

the second reservoir chamber in fluid communication with the second fluid chamber of the shock housing via a reservoir tube, with a reservoir end of the reservoir tube positioned within the second reservoir chamber of the remote reservoir and an opposing shock end of the reservoir tube positioned within the second fluid chamber of the shock housing;

the reservoir end of the reservoir tube providing an eductor nozzle configured for introducing a volume of shock fluid from the second fluid chamber of the shock housing into the second reservoir chamber of the remote reservoir using the Venturi effect when the shock piston moves from a rebound position into the compressed position, the eductor nozzle comprising:

a converging first eductor end positioned proximal to the reservoir end of the reservoir tube;

a diverging second eductor end positioned distal to the reservoir end of the reservoir tube;

a constricted throat portion positioned between the first eductor end and second eductor end; and

an eductor base positioned between the first eductor end and the reservoir end of the reservoir tube, the eductor base providing an at least one eductor aperture positioned on a sidewall of the eductor base;

the second end of the reservoir housing providing a substantially concave eductor surface, with the eductor nozzle extending substantially perpendicularly from a center of the concave eductor surface; and

the second end of the reservoir piston providing a substantially concave piston surface, substantially longitudinally opposing the concave eductor surface, with a protrusion extending substantially perpendicularly from a center of the concave piston surface, such that the protrusion is substantially axially aligned with the second eductor end of the eductor nozzle.