Velocity sensitive dual rate shock strut
OwnerFranklin C. Sandersinventor
Life of this patent
Estimating the term…
Abstract
A shock strut employing fluid as a damping medium and gas trapped in a primary chamber above the fluid as a spring is modified by adding a secondary chamber with an orificed inlet to the primary chamber above the normal fluid level. For low velocity deflections of the strut, the gas can pass freely through the orifice so that the effective volume into which the gas is compressed is enlarged thereby reducing the spring rate. For high velocity deflections, the orifice meters the passage of the gas to the secondary chamber so that a higher spring rate is momentarily present. On extreme deflections, the fluid level within the strut reaches the orifice which severely restricts flow therethrough to cause a second greatly increased spring rate for the gaseous spring which also is velocity sensitive.
Claims16
In a shock absorbing strut having first and second hollow telescoping portions, said first hollow telescoping portion having an interior, damping means including a fluid medium with a top surface and a primary chamber in said first hollow telescoping portion formed by said first hollow telescoping portion and the top surface of said fluid medium wherein a gaseous medium is retained and compressed by upward movement of said top surface caused by retraction movement of said second hollow telescoping portion with respect to the first, the improvement comprising:
- a secondary chamber defining a predetermined volume;
- and
- orifice means located between said secondary chamber and the interior of said first hollow telescoping portion, said orifice means being positioned with respect to said fluid medium top surface to allow communication of said gaseous medium into and out of said secondary chamber when said strut is in a generally extended condition and to allow communication of the fluid medium into said secondary chamber when said strut is in a generally retracted condition.
Means for modifying the reaction of a shock strut containing fluid as a damping agent and gas as a spring agent to retraction and extension forces, said means including:
- a container defining a predetermined volume;
- orifice means connected in communication with said container and adapted to communicate with the gas and fluid in said strut;
- means to retain said orifice means in sealed communication with said strut;
- and
- a strut plug bolt having a top and a bottom wherein said container is sealably attached to the top of said strut plug bolt, said orifice means including a hollow tube attached to the bottom of said strut plug bolt, and the plug bolt having an opening defined therethrough communicating said tube and said container.
A device for modifying the reaction of a shock strut to retraction and extension forces, the shock strut being of the kind containing fluid as a damping agent and gas as a spring agent, wherein the fluid and gas have an interface which moves to different levels in the strut in response to the extension and retraction forces applied to the strut, said device including:
- a container defining a predetermined volume;
- and
- a base member connected to said container having a semi-cylindrical surface for engagement with the strut, a passageway from said predetermined volume to said semi-cylindrical surface of a size to form an orifice, a seal formed about said passageway on said semi-cylindrical surface, and means to clamp said base member to the strut and to maintain a sealed condition therebetween, whereby said passageway can be held in sealed communication with an opening in the strut so that the passage of the interface thereby modifies the reaction of the shock strut.
Dependencies are inferred from the claim text.