IP Library Granted Patent US 12,496,867
Granted Patent B2
US 12,496,867 · App. 17/507,357 · Granted Dec 16, 2025

Hydraulically-adjustable preload and/or cross-over

Inventors: Connor Randall (Salida, CO); Regan Woelfel (Scotts Valley, CA)
Assignee: Fox Factory, Inc.
B60G17/08F15B15/1447B60G13/08B60G2202/24B60G2206/41B60G2500/10B60G2500/30B60G2800/162
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Quick Facts
Patent No.
US 12,496,867
App. No.
17/507,357
Granted
Dec 16, 2025
Kind
B2
Abstract

A modular hydraulically-adjustable preload and/or cross-over system. The system includes a housing configured to couple with a main damper cylinder, the housing including a slave cylinder within a portion of a slave cylinder chamber, the slave cylinder telescopically movable with respect to the housing; a fluid chamber; and a fluid port configured to provide a fluid flow for the fluid chamber, wherein an increase in a fluid volume within the fluid chamber causes a portion of the slave cylinder to telescopically extend from the slave cylinder chamber. A preload flange coupled with the slave cylinder at an end of the housing such that a change in a location of the slave cylinder causes a change in a location of the preload flange.

Claims (53)

1 . A hydraulically-adjustable preload system comprising:

a housing configured to couple with a main damper cylinder, said housing comprising:

a slave cylinder chamber;

a slave cylinder within a portion of said slave cylinder chamber, said slave cylinder telescopically movable with respect to said housing in a direction along an axis of said main damper cylinder;

a fluid chamber within a portion of said slave cylinder chamber; and

a fluid port configured to provide a fluid flow for said fluid chamber, wherein an increase in a fluid volume within said fluid chamber causes a portion of said slave cylinder to telescopically extend from said slave cylinder chamber in an axial direction along said main damper cylinder;

a preload flange coupled with said slave cylinder at an end of said housing, said preload flange disposed such that a change in a location of said slave cylinder causes a change in a location of said preload flange and a corresponding change in a preload applied to a coil spring coupled with said housing, said coil spring disposed surrounding an external surface of said main damper cylinder, said coil spring having a first end coupled with said preload flange and a second end coupled with a lower flange, said coil spring applying a pressure to said preload flange and said lower flange to maintain a length which a damping rod initially extends from said main damper cylinder, said preload flange providing an initial preload to said hydraulically-adjustable preload system, said initial preload occurring prior to any additional telescopic movement of said slave cylinder in said axial direction along said main damper cylinder occurring during operation of said main damper cylinder; and

an adjustable crossover coupled with said preload flange, said adjustable crossover disposed such that said change in said location of said preload flange causes a change in a location of said adjustable crossover.

2 . The hydraulically-adjustable preload system of claim 1 , further comprising:

said fluid port configured to provide a fluid flow for said fluid chamber, wherein a decrease in said fluid volume within said fluid chamber allows said portion of said slave cylinder to telescopically retract into said slave cylinder chamber.

3 . The hydraulically-adjustable preload system of claim 1 , further comprising:

a hose coupled with said fluid port; and

a pump coupled with said hose, said pump configured to pump a fluid via said hose into said fluid port to increase said fluid volume in said slave cylinder chamber and receive said fluid via said hose from said fluid port to reduce said fluid volume in said slave cylinder chamber.

4 . The hydraulically-adjustable preload system of claim 3 , wherein said pump is selected from a group consisting of: a motor turning a lead screw to drive a master piston, a hydraulic pump.

5 . The hydraulically-adjustable preload system of claim 3 , further comprising:

an accumulator operationally coupled with said pump, said accumulator to provide an increase in actuation that is greater than an actuation of said pump alone.

6 . The hydraulically-adjustable preload system of claim 1 , wherein said hydraulically-adjustable preload system is a modular hydraulically-adjustable preload system configured to be retrofit to said main damper cylinder of a legacy shock assembly.

7 . A hydraulically-adjustable crossover system comprising:

a housing configured to couple with a main damper cylinder in an adjustably fixed location, said housing comprising:

a slave cylinder chamber;

a slave cylinder within a portion of said slave cylinder chamber, said slave cylinder telescopically movable with respect to said housing in a direction along an axis of said main damper cylinder;

a fluid chamber within a portion of said slave cylinder chamber; and

a fluid port configured to provide a fluid flow for said fluid chamber, wherein an increase in a fluid volume within said fluid chamber causes a portion of said slave cylinder to telescopically extend from said slave cylinder chamber in an axial direction along said main damper cylinder; and

an adjustable crossover coupled with said slave cylinder at an end of said housing, said adjustable crossover disposed such that a change in a location of said slave cylinder causes a change in a location of said adjustable crossover, said adjustable crossover including a clocking ring for defining an initial position of said adjustable crossover with respect to said housing, said adjustable crossover configured to extend or retract with respect to said housing in a direction along a central axis of said main damper cylinder parallel with a damping rod.

8 . The hydraulically-adjustable crossover system of claim 7 , further comprising:

a preload flange coupled with said slave cylinder at said end of said housing, said preload flange disposed such that a change in said location of said slave cylinder causes a change in a location of said preload flange, said preload flange providing an initial preload to said hydraulically-adjustable crossover system, said initial preload occurring prior to any additional telescopic movement of said slave cylinder in said axial direction along said main damper cylinder occurring during operation of said main damper cylinder.

9 . The hydraulically-adjustable crossover system of claim 7 , further comprising:

said fluid port configured to provide a fluid flow for said fluid chamber, wherein a decrease in said fluid volume within said fluid chamber allows said portion of said slave cylinder to telescopically retract into said slave cylinder chamber.

10 . The hydraulically-adjustable crossover system of claim 7 , further comprising:

a hose coupled with said fluid port; and

a pump coupled with said hose, said pump configured to pump a fluid via said hose into said fluid port to increase said fluid volume in said slave cylinder chamber and receive said fluid via said hose from said fluid port to reduce said fluid volume in said slave cylinder chamber.

11 . The hydraulically-adjustable crossover system of claim 10 , wherein said pump is selected from a group consisting of: a motor turning a lead screw to drive a master piston, a hydraulic pump.

12 . The hydraulically-adjustable crossover system of claim 10 , further comprising:

an accumulator operationally coupled with said pump, said accumulator to provide an increase in actuation that is greater than an actuation of said pump alone.

13 . The hydraulically-adjustable crossover system of claim 7 , wherein said hydraulically-adjustable crossover system is a modular hydraulically-adjustable crossover system configured to be retrofit to said main damper cylinder of a legacy shock assembly.

14 . A modular hydraulically-adjustable preload and crossover system comprising:

a clocking ring configured to couple with a main damper cylinder in an adjustably fixed location;

a housing coupled with said clocking ring, said housing comprising:

a slave cylinder chamber;

a slave cylinder within a portion of said slave cylinder chamber, said slave cylinder telescopically movable with respect to said housing in a direction along an axis of said main damper cylinder;

a fluid chamber within a portion of said slave cylinder chamber; and

a fluid port configured to provide a fluid flow for said fluid chamber, wherein an increase in a fluid volume within said fluid chamber causes a portion of said slave cylinder to telescopically extend from said slave cylinder chamber in an axial direction along said main damper cylinder;

a preload flange coupled with said slave cylinder at an end of said housing opposite of said clocking ring, said preload flange disposed such that a change in a location of said slave cylinder causes a change in a location of said preload flange and a corresponding change in a preload applied to a coil spring coupled with said housing, said coil spring disposed surrounding an external surface of said main damper cylinder, said coil spring having a first end coupled with said preload flange and a second end coupled with a lower flange, said coil spring applying a pressure to said preload flange and said lower flange to maintain a length which a damping rod initially extends from said main damper cylinder, said preload flange providing an initial preload to said modular hydraulically-adjustable preload and crossover system, said initial preload occurring prior to any additional telescopic movement of said slave cylinder in said axial direction along said main damper cylinder occurring during operation of said main damper cylinder; and

an adjustable crossover coupled with said preload flange, said adjustable crossover disposed such that said change in said location of said preload flange causes a change in a location of said adjustable crossover, said adjustable crossover including said clocking ring for defining an initial position of said adjustable crossover with respect to said housing, said adjustable crossover configured to extend or retract with respect to said housing in a direction along a central axis of said main damper cylinder parallel with a damping rod.

15 . The modular hydraulically-adjustable preload and crossover system of claim 14 , wherein said adjustable crossover is coupled with said preload flange via a threaded connection such that said location of said adjustable crossover is manually adjustable with respect to said preload flange.

16 . The modular hydraulically-adjustable preload and crossover system of claim 14 , further comprising:

said fluid port configured to provide a fluid flow for said fluid chamber, wherein a decrease in said fluid volume within said fluid chamber allows said portion of said slave cylinder to telescopically retract into said slave cylinder chamber.

17 . The modular hydraulically-adjustable preload and crossover system of claim 14 , further comprising:

a hose coupled with said fluid port; and

a pump coupled with said hose, said pump configured to pump a fluid via said hose into said fluid port to increase said fluid volume in said slave cylinder chamber and receive said fluid via said hose from said fluid port to reduce said fluid volume in said slave cylinder chamber.

18 . The modular hydraulically-adjustable preload and crossover system of claim 17 , wherein said pump is selected from a group consisting of: a motor turning a lead screw to drive a master piston, a hydraulic pump.

19 . The modular hydraulically-adjustable preload and crossover system of claim 17 , further comprising:

an accumulator operationally coupled with said pump, said accumulator to provide an increase in actuation that is greater than an actuation of said pump alone.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 22, 2025
From: RANDALL, CONNOR; WOELFEL, REGAN
To: FOX FACTORY, INC.
Reel/Frame 072645/0491 →
SECURITY INTEREST Recorded Apr 5, 2022
From: FOX FACTORY, INC.
To: WELLS FARGO BANK, NATIONAL ASSOCIATION
Reel/Frame 059616/0435 →
Continuity (7)
Continuation In Part 17185691 · Feb 25, 2021
Continuation In Part 17185766 · Feb 25, 2021
Provisional Application 63110204 · Nov 5, 2020
Provisional Application 63105796 · Oct 26, 2020
Provisional Application 62982645 · Feb 27, 2020
Provisional Application 62982629 · Feb 27, 2020
Related Publication 20220041029A1 · Feb 10, 2022
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