Suspension element systems and methods

Patent metadata

Field	Value
Publication number	US-11199239-B2
Application number	US-201916276273-A
Country	US
Kind code	B2
Filing date	Feb 14, 2019
Priority date	Mar 10, 2013
Publication date	Dec 14, 2021
Grant date	Dec 14, 2021

Abstract

A damper assembly includes a tubular member including a sidewall and a shoulder. The damper assembly includes a rod and a piston coupled to the rod. A secondary piston has a second contact surface, an opposing second surface, an inner cylindrical face defining a central aperture that receives the rod, and an outer cylindrical face. The opposing second surface includes one or more surface grooves, extending between the inner cylindrical face and the outer cylindrical face along the opposing second surface, and one or more bypass orifices disposed about the body member. The bypass orifices extend along the inner cylindrical face between the second contact surface and the opposing second surface. The secondary piston defines a channel extending between the inner cylindrical face and an outer periphery of the body member. The channel and bypass orifices form a fluid flow path when the piston contacts the secondary piston.

First claim

What is claimed is:

1. A damper assembly, comprising:
a tubular member including a sidewall and a cap at an end of the sidewall, the sidewall and the cap defining an inner volume, wherein the sidewall comprises a first portion and a second portion, wherein the first portion and the second portion define a shoulder;
a rod extending within the inner volume;
a primary piston positioned within the inner volume and coupled to the rod, the primary piston defining a first contact surface;
a secondary piston comprising:
a body member comprising a second contact surface, an opposing second surface, an inner cylindrical face defining a central aperture that receives the rod, and an outer cylindrical face, wherein the opposing second surface comprises one or more surface grooves disposed about the body member, extending across an entire radial width of the opposing second surface from the inner cylindrical face to the outer cylindrical face;
one or more bypass orifices disposed about the body member, wherein the one or more bypass orifices extend along the inner cylindrical face between the second contact surface and the opposing second surface;

wherein the secondary piston defines a channel extending between the inner cylindrical face and an outer periphery of the body member, wherein the primary piston and the secondary piston separate the inner volume into a first working chamber, a second working chamber, and a recoil chamber;
a resilient member disposed between the secondary piston and the cap and thereby positioned to bias the secondary piston into engagement with the shoulder;
wherein the first contact surface and the channel are configured to cooperatively define a flow conduit upon engagement between the primary piston and the secondary piston;
wherein the second contact surface is configured to engage the first contact surface such that an open flow path is formed from the recoil chamber through the central aperture and the flow conduit upon engagement between the primary piston and the secondary piston.

2. The damper assembly of claim 1 , wherein the primary piston is moveable within the tubular member between a first location, an intermediate location, and an end of stroke, and wherein the primary piston is configured to maintain engagement with the secondary piston between the intermediate location and the end of stroke.

3. The damper assembly of claim 1 , wherein the recoil chamber is defined between the opposing second surface of the secondary piston and the cap.

4. The damper assembly of claim 1 , wherein one or more of the one or more surface grooves are angled relative to a centerline extending radially outwards from a center of the secondary piston.

5. The damper assembly of claim 4 , wherein one or more of the one or more surface grooves are at an angle between 110 and 160 degrees relative to the centerline extending radially outwards from the center of the secondary plunger.

6. The damper assembly of claim 5 , wherein the first portion has a first diameter and the second portion has a second diameter, wherein the first diameter is greater than the second diameter, and wherein the transition between the first portion and the second portion defines the shoulder.

7. The damper assembly of claim 6 , wherein the diameter of the primary piston is less than the second diameter such that the primary piston is extendable along the length of the tubular member.

8. The damper assembly of claim 1 , wherein each of the one or more bypass orifices are adjacent to one of the one or more surface grooves.

9. A damper assembly, comprising:
a housing having an end cap and defining an inner volume, wherein the housing includes a first portion and a second portion, wherein the transition between the first portion and the second portion defines a shoulder;
a primary piston positioned within the housing; and
a limiter positioned between the primary piston and the end cap, the limiter comprising a damper piston comprising a body member having:
a contact surface;
an inner cylindrical face that defines an aperture through a central portion of the body member;
an outer cylindrical face;
an opposing second surface, wherein the opposing second surface comprises one or more surface grooves disposed about the body member, extending across an entire radial width of the opposing second surface from the inner cylindrical face to the outer cylindrical face;
one or more bypass orifices disposed about the body member, wherein the one or more bypass orifices extend along the inner cylindrical face between the second contact surface and the opposing second surface;

wherein the primary piston and the damper piston separate the inner volume into a first working chamber, a second working chamber, and a recoil chamber;
a resilient member disposed within the recoil chamber, between the opposing second surface of the damper piston and the end cap, the resilient member thereby positioned to bias the damper piston into engagement with the shoulder; and
a rod coupled to the primary piston and extending through the aperture defined by the damper piston;
wherein the damper piston defines a channel extending laterally outward from the inner cylindrical face across the contact surface to an outer periphery of the body member, wherein the primary piston and the channel are configured to cooperatively define a first flow conduit upon engagement between the primary piston and the damper piston; and
wherein an outer surface of the rod and the inner cylindrical face of the damper piston define a second flow conduit, and wherein the first flow conduit and the second flow conduit cooperate to define an open flow path from the recoil chamber.

10. The damper assembly of claim 9 , wherein the primary piston, the first portion, and the second portion have circular cross-sectional shapes.

11. The damper assembly of claim 10 , wherein the first portion has a first diameter and the second portion has a second diameter, wherein the first diameter is greater than the second diameter, and wherein the transition between the first portion and the second portion defines the shoulder.

12. The damper assembly of claim 11 , wherein the diameter of the primary piston is less than the second diameter such that the primary piston is extendable along the length of the housing.

13. The damper assembly of claim 12 , wherein the primary piston and the housing cooperatively define a space around an outer periphery of the primary piston thereby providing a flow path around the outer periphery of the primary piston.

14. The damper assembly of claim 9 , wherein each of the one or more bypass orifices are adjacent to one of the one or more surface grooves.

15. The damper assembly of claim 9 , wherein the primary piston is moveable within the housing between a first location, an intermediate location, and an end of stroke, and wherein the primary piston is configured to maintain engagement with the limiter between the intermediate location and the end of stroke.

16. The damper assembly of claim 9 , wherein one or more of the one or more surface grooves are angled relative to a centerline extending radially outwards from a center of the damper piston.

17. The damper assembly of claim 16 , wherein one or more of the one or more surface grooves are at an angle between 110 and 160 degrees relative to the centerline extending radially outwards from the center of the damper piston.

18. The damper assembly of claim 9 , wherein the recoil chamber is defined between the opposing second surface of the damper piston and the

Assignees

• Oshkosh Defense Llc

Inventors

• Dumitru Paul
• Rositch Aaron
• Ellifson Erik
• Dillman Patrick
• Schubart Kai
• Sollenskog Robert

Classifications

• B60G3/20 Primary

  all arms being rigid · CPC title

• B60G2204/129

  Damper mount on wheel suspension or knuckle · CPC title

• B60G2500/30

  Height or ground clearance · CPC title

• B60G2206/8105

  by extrusion · CPC title

• B60G17/08

  Characteristics of fluid dampers (adjusting fluid dampers in general F16F9/44 - F16F9/53) · CPC title