US-12618446-B2 - Damper assembly

US12618446B2US 12618446 B2US12618446 B2US 12618446B2US-12618446-B2

Abstract

A damper assembly includes an outer cylinder, an inner cylinder positioned at least partially within the outer cylinder, a cap coupled to the inner cylinder, and a plunger positioned radially inward from the inner cylinder and coupled to a rod. The plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber. The suspension system further includes a passage extending through the rod and fluidly coupled with the first chamber, a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder, a first port in fluid communication with the plunger, the cap, and the inner cylinder through the passage, and a second port in fluid communication with the piston, the inner cylinder, and the outer cylinder. The piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber.

Inventors

Erik Ellifson
Darin Rosenboom

Assignees

OSHKOSH DEFENSE, LLC

Dates

Publication Date: 20260505
Application Date: 20220615

Claims (20)

1 . A damper assembly comprising: an outer cylinder at least partially defining a fluid flow path therewithin; an inner cylinder positioned at least partially within the outer cylinder; a cap coupled to the inner cylinder; a plunger positioned radially inward from the inner cylinder and coupled to a rod, wherein the plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber; a passage extending through the rod and fluidly coupled with the first chamber; a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder, wherein the piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber; a barrier coupled to the outer cylinder and extending radially inward toward the inner cylinder, wherein the barrier prevents fluid flow between outer cylinder and the barrier; a fluid passage opening defined in the outer cylinder, the fluid passage opening fluidly connecting the second chamber and the fluid flow path within the outer cylinder, the fluid passage opening spaced a distance apart from the barrier in a direction away from the cap, wherein an outer circumferential surface of the piston is configured to move along an interior surface of the outer cylinder and at least partially across the fluid passage opening; a first port in fluid communication with the plunger, the cap, and the inner cylinder through the passage; and a second port in fluid communication with the piston, the inner cylinder, the outer cylinder, and the second chamber.
2 . The damper assembly of claim 1 , wherein the first port is located on an exterior of the damper assembly, and wherein the second port is located on the exterior of the damper assembly.
3 . The damper assembly of claim 1 , wherein the plunger is configured to move relative to the inner cylinder, and wherein the piston is configured to move relative to the outer cylinder.
4 . The damper assembly of claim 3 , wherein the plunger is fixed to an end portion of the rod, and wherein movement of the plunger relative to the inner cylinder changes a volume of the first chamber.
5 . The damper assembly of claim 4 , wherein the movement of the plunger relative to the inner cylinder moves the piston relative to the outer cylinder and changes a volume of the second chamber.
6 . The damper assembly of claim 5 , wherein when the volume of the first chamber increases, the volume of the second chamber decreases.
7 . The damper assembly of claim 1 , wherein the barrier at least partially defines the second chamber.
8 . The damper assembly of claim 7 , further comprising an accumulator in fluid communication with at least one of the first chamber and the second chamber.
9 . The damper assembly of claim 8 , wherein the first chamber is at least partially defined by a face of the plunger, and wherein the face of the plunger has a cross-sectional area that is substantially equal to the cross-sectional area of a portion of the piston that at least partially defines the second chamber.
10 . The damper assembly of claim 1 , wherein the inner cylinder includes internal threads and a stem of the cap includes external threads adjustably received within the internal threads.
11 . The damper assembly of claim 1 , wherein each of the first chamber, the second chamber, and the fluid flow path receive hydraulic fluid.
12 . The damper assembly of claim 1 , wherein the rod has an outer diameter that is smaller than an inner diameter of the inner cylinder.
13 . A damper assembly comprising: an outer cylinder at least partially defining a fluid flow path therewithin, the fluid flow path containing a hydraulic fluid; an inner cylinder positioned at least partially within the outer cylinder; a cap coupled to the inner cylinder; a plunger coupled to a rod, wherein the plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber, wherein the plunger extends across a gap between the inner cylinder and the rod, and wherein the plunger prevents fluid from passing through the plunger between the inner cylinder and the rod; a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder, and wherein the piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber; and a barrier coupled to the outer cylinder and extending radially inward toward the inner cylinder, wherein the barrier prevents fluid flow between outer cylinder and the barrier; and a fluid passage opening defined in the outer cylinder, the fluid passage opening fluidly connecting the second chamber and the fluid flow path within the outer cylinder, the fluid passage opening spaced a distance apart from the barrier in a direction away from the cap, and wherein the piston is configured to move along an interior surface of the outer cylinder and at least partially across the fluid passage opening.
14 . The damper assembly of claim 13 , wherein relative displacement between the inner cylinder and the outer cylinder in a first direction increases a volume of the first chamber and decreases a volume of the second chamber.
15 . The damper assembly of claim 14 , wherein relative displacement between the inner cylinder and the outer cylinder in a second direction opposite the first direction decreases the volume of the first chamber and increases the volume of the second chamber.
16 . The damper assembly of claim 13 , wherein the plunger is fixed to an end of the rod, and wherein movement of the plunger relative to the inner cylinder changes a volume of the first chamber.
17 . The damper assembly of claim 16 , wherein the barrier at least partially defines the second chamber.
18 . A vehicle, comprising: a vehicle body; and a suspension system coupled to the vehicle body, the suspension system comprising: a first damper comprising: an inner cylinder extending within an outer cylinder, the outer cylinder at least partially defining a fluid flow path therewithin; a rod extending within the inner cylinder, an annular gap extending between an outer surface of the rod and an inner surface of the inner cylinder; a plunger coupled to the rod, extending within the inner cylinder and across the annular gap, and movable relative to the inner cylinder; a first chamber at least partially defined by the plunger and the inner cylinder; and a second chamber at least partially defined by an exterior surface of the inner cylinder, the outer cylinder, and a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder; a barrier coupled to the outer cylinder and extending radially inward toward the inner cylinder, wherein the barrier prevents fluid flow between outer cylinder and the barrier; and a fluid passage opening defined in the outer cylinder, the fluid passage opening connecting the second chamber and the fluid flow path within the outer cylinder, the fluid passage opening spaced a distance apart from the barrier, wherein the piston is configured to move along an interior surface of the outer cylinder and at least partially across the fluid passage opening; and a second damper comprising: a third chamber having a variable volume; and a fourth chamber having a variable volume, wherein the first chamber is fluidly coupled to the third chamber through the plunger; and wherein the second chamber is fluidly coupled to the fourth chamber.
19 . The vehicle of claim 18 , wherein the suspension system further comprises: a first accumulator coupled to a first conduit, the first conduit coupling the first chamber to the third chamber to facilitate fluid communication therebetween; and a second accumulator coupled to a second conduit, the second conduit coupling the second chamber to the fourth chamber to facilitate fluid communication therebetween, wherein a response of the first damper and the second damper is at least partially controlled via operation of the first accumulator and the second accumulator.
20 . The damper assembly of claim 1 , wherein the barrier is either a rod-end head or a rod gland.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS This application is a continuation of U.S. Application No. 17,462,924, filed Aug. 31, 2021, which is a continuation of U.S. application Ser. No. 16/517,209, filed Jul. 19, 2019, now U.S. Pat. No. 11,209,067, which is a continuation of U.S. application Ser. No. 15/707,675, filed Sep. 18, 2017, now U.S. Pat. No. 10,422,403, which is a continuation of U.S. application Ser. No. 14/846,600, filed Sep. 4, 2015, now U.S. Pat. No. 9,765,841, which is a continuation of U.S. application Ser. No. 13/047,648, filed Mar. 14, 2011, now U.S. Pat. No. 9,127,738, all of which are incorporated herein by reference in their entireties. BACKGROUND The present application relates general to the field of suspension systems for vehicles. More specifically the present application relates to hydraulic shock absorbers. Dashpots, and more specifically dampers, function as shock absorbers for vehicles. The dampers are typically formed from hydraulic cylinders, such as double-acting cylinders. The hydraulic cylinder includes a rod end, a cap end, and a plunger (or piston) on an end of a rod. Movement of the plunger drives hydraulic fluid into and out of the rod and cap ends. Friction from movement of the hydraulic fluid through the cylinder and associated plumbing dissipates energy associated with actuation of the suspension system in a manner proportional to the velocity of the actuation. SUMMARY One exemplary embodiment relates to a damper assembly including an outer cylinder, an inner cylinder positioned at least partially within the outer cylinder, a cap coupled to the inner cylinder, and a plunger positioned radially inward from the inner cylinder and coupled to a rod. The plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber. The suspension system further includes a passage extending through the rod and fluidly coupled with the first chamber, a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder, a first port in fluid communication with the plunger, the cap, and the inner cylinder through the passage, and a second port in fluid communication with the piston, the inner cylinder, and the outer cylinder. The piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber. Another exemplary embodiment relates to a damper assembly including an outer cylinder, an inner cylinder positioned at least partially within the outer cylinder, a cap coupled to the inner cylinder, a plunger coupled to a rod, wherein the plunger, the cap, and the interior of the inner cylinder at least partially define a first chamber, and a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder. The piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber. The plunger prevents fluid from passing through the plunger between the inner cylinder and the rod. Still another exemplary embodiment relates to a vehicle including a vehicle body and a suspension system coupled to the vehicle body. The suspension system includes a first damper having a variable volume and a second damper having a variable volume. The second damper includes a third chamber having a variable volume and a fourth chamber having a variable volume. The first chamber is fluidly coupled to the third chamber, and the second chamber is fluidly coupled to the fourth chamber. Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited in the claims. BRIEF DESCRIPTION OF THE FIGURES The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, in which: FIG. 1 is a perspective view of an axle assembly according to an exemplary embodiment of the invention. FIG. 2 is a perspective view of a suspension system of the axle assembly of FIG. 1. FIG. 3 is a sectional view of a damper according to an exemplary embodiment of the invention. FIG. 4 is a sectional view of the damper of FIG. 3, taken along line 4-4 as shown in FIG. 3. FIG. 5 is a sectional view of a damper according to another exemplary embodiment of the invention. FIG. 6 is a sectional view of the damper of FIG. 5, in another configuration. FIG. 7 is a sectional view of a damper according to yet another exemplary embodiment of the invention. FIG. 8 is a sectional view of a damper according to still another exemplary embodiment of the invention. FIG. 9 is a perspective view of dampers of the axle assembly of FIG. 1. FIG. 10 is a schematic diagram of a vehicle suspension system and a damper according to another exemplary embodiment of the invention. DETAILED DESCRIPTION Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present application is not limited to the details or met