Additively manufactured energy absorbing strut device

Patent metadata

Field	Value
Publication number	US-12429105-B2
Application number	US-202318199096-A
Country	US
Kind code	B2
Filing date	May 18, 2023
Priority date	Aug 4, 2022
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

An additively manufactured strut device including a cylinder body forming a chamber and a piston having a first part disposed in the internal chamber and a second part disposed outside of the chamber. A first deformable element formed as a lattice structure breaks to permit initial withdrawal of the piston when a tensive threshold is met and a second deformable crushes during continued withdrawal of the piston. In further embodiments, a third deformable element formed as a lattice structure may be collocated with the second deformable element. The strut may be manufactured by an additive manufacturing process. Applications for the energy absorbing strut include aircraft seat frames among other applications.

First claim

What is claimed is:

1. An energy absorbing strut device, comprising:
a cylinder body having an internal chamber and a first axial end attachable to a first component;
a piston having a first part disposed inside the internal chamber and a second part disposed outside of the internal chamber, wherein a piston head is formed at an axial end of the first part, and wherein an axial end of the second part is attachable to a second component;
a first deformable element positioned outside of the cylinder body, the first deformable element connected to the cylinder body and to the first part of the piston, the first deformable element configured to break, responsive to tension, to permit initial withdrawal of the piston relative to the cylinder body; and
a second deformable element positioned inside the internal chamber and configured to be deformed by the piston head during continued withdrawal of the piston relative to the cylinder body.

2. The energy absorbing strut device according to claim 1 , wherein:
the first deformable element is an annular lattice structure having a first axial end connected to the second part of the piston and a second axial end connected to a second axial end of the cylinder body; and
the annular lattice structure is configured to break into at least two separate parts.

3. The energy absorbing strut device according to claim 1 , further comprising a third deformable element positioned inside the cylinder body and configured to be crushed by the piston head during the continued withdrawal of the piston relative to the cylinder body.

4. The energy absorbing strut device according to claim 3 , wherein the first deformable element and the third deformable element are annular variable density lattice structures.

5. The energy absorbing strut device according to claim 3 , wherein:
the second deformable element is a deformable tube;
the third deformable element is an annular lattice structure positioned between the second deformable element and the first part of the piston and circumferentially surrounding the first part of the piston; and
the piston head is configured to engage an axial end of the deformable tube and an axial end of the third deformable element to cause the deformable tube and the third deformable element to deform during the continued withdrawal of the piston from the cylinder body.

6. The energy absorbing strut device according to claim 1 , wherein the second deformable element is a single-walled tube or a double-walled tube.

7. The energy absorbing strut device according to claim 1 , wherein the first deformable element is an annular variable density lattice structure.

8. The energy absorbing strut device according to claim 1 , manufactured by an additive manufacturing process.

9. An aircraft seat frame, comprising:
a first frame component;
a second frame component; and
an energy absorbing strut device forming a connecting link between the first frame component and the second frame component, the energy absorbing struct device comprising:
a cylinder body having an internal chamber and a first axial end attached to the first frame component;
a piston having a first part disposed inside the internal chamber and a second part disposed outside of the internal chamber, wherein a piston head is formed at an axial end of the first part, and wherein an axial end of the second part is attached to the second frame component;
a first deformable element positioned outside of the cylinder body, the first deformable element connected to the cylinder body and to the first part of the piston, the first deformable element configured to break, responsive to tension, to permit initial withdrawal of the piston relative to the cylinder body; and
a second deformable element positioned inside the internal chamber and configured to be deformed by the piston head during continued withdrawal of the piston relative to the cylinder body.

10. The aircraft seat frame according to claim 9 , wherein:
the first deformable element is an annular lattice structure having a first axial end connected to the second part of the piston and a second axial end connected to a second axial end of the cylinder body; and
the annular lattice structure is configured to break into at least separate parts.

11. The aircraft seat frame according to claim 9 , further comprising a third deformable element positioned inside the cylinder body and configured to be crushed by the piston head during the continued withdrawal of the piston relative to the cylinder body.

12. The aircraft seat frame according to claim 11 , wherein the first deformable element and the third deformable element are annular variable density lattice structures.

13. The aircraft seat frame according to claim 11 , wherein:
the second deformable element is a deformable tube;
the third deformable element is an annular lattice structure positioned between the second deformable element and the first part of the piston and circumferentially surrounding the first part of the piston; and
the piston head is configured to engage an axial end of the crushable tube and an axial end of the third deformable element to cause the crushable tube and the third deformable element to deform during the continued withdrawal of the piston from the cylinder body.

14. The aircraft seat frame according to claim 9 , wherein the second deformable element is a single-walled tube or a double-walled tube.

15. The aircraft seat frame according to claim 9 , wherein:
the energy absorbing strut device is manufactured by an additive manufacturing process;
the first frame component is a track fastener; and
the second frame component is a leg or is attached to a leg.

Assignees

• Be Aerospace Inc

Inventors

• Acharya Pradeep
• Rao Sreekanth
• Dempah Maxime
• Hosmani Mahesh

Classifications

• B33Y80/00 Primary

  Products made by additive manufacturing · CPC title

• F16F2236/06

  Tension · CPC title

• F16F2232/08

  Linear · CPC title

• F16F2236/04

  Compression · CPC title

• B64D11/0619

  with energy absorbing means specially adapted for mitigating impact loads for passenger seats, e.g. at a crash · CPC title