Shape memory alloy valve for an electronic device

Patent metadata

Field	Value
Publication number	US-12389168-B2
Application number	US-202318306847-A
Country	US
Kind code	B2
Filing date	Apr 25, 2023
Priority date	May 19, 2022
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

An in-ear electronic device comprising: an enclosure having an enclosure wall that defines an interior chamber surrounding a transducer and an opening from the interior chamber to an ambient environment surrounding the enclosure; and an acoustic valve comprising a driven member coupled to a driving member having a lever and a shape memory alloy operable to cause the driven member to open and close the opening upon application of a current.

First claim

What is claimed is:

1. An in-ear electronic device comprising:
an enclosure having an enclosure wall that defines an interior chamber surrounding a transducer and an opening along a first axis from the interior chamber to an ambient environment surrounding the enclosure; and
an acoustic valve comprising a piston coupled to a lever and a shape memory alloy operable to cause the lever to rotate about a second axis perpendicular to the first axis such that the piston is driven by the lever in a direction parallel to the first axis of the opening to open and close the opening upon application of a current.

2. The in-ear electronic device of claim 1 wherein the shape memory alloy comprises a first shape memory alloy wire and a second shape memory alloy wire coupled to the lever in a parallel arrangement.

3. The in-ear electronic device of claim 2 wherein the first shape memory alloy wire and the second shape memory alloy wire are separately activated by the current to cause the lever to rotate between a first position that causes the piston to close the opening and a second position that causes the piston to open the opening.

4. The in-ear electronic device of claim 1 further comprising a bistable spring coupled to the piston.

5. The in-ear electronic device of claim 4 wherein the bistable spring comprises a buckled flexure that holds the piston in a closed position in a first state and holds the piston in an open position in a second state in an absence of the current.

6. The in-ear electronic device of claim 5 wherein the buckled flexure is further operable to guide the driven member in the direction parallel to the first axis of the opening between the closed position and the open position.

7. The in-ear electronic device of claim 1 further comprising a damping member to dampen a transition of the piston between an open position and a closed position.

8. A portable electronic device comprising:
an enclosure having an enclosure wall defining an interior chamber separated from a surrounding ambient environment and an acoustic opening from the interior chamber;
a transducer positioned within the interior chamber and dividing the interior chamber into a first chamber comprising a first side of the transducer and the acoustic opening, and a second chamber comprising a second side of the transducer; and
a shape memory alloy valve operable to open and close a vent between the first chamber or the second chamber and the surrounding ambient environment, the shape memory alloy valve comprising a piston operable to move between an open position and a closed position by a lever coupled to a pair of parallel shape memory alloy wires and comprising a bistable buckled flexure operable to transition between a first stable state and a second stable state upon application of a force and in the first stable state the bistable buckled flexure holds the shape memory alloy valve in the open position to open the vent and in the second stable state the bistable buckled flexure holds the shape memory alloy valve in the closed position to close the vent in an absence of a current.

9. The portable electronic device of claim 8 wherein the pair of shape memory alloy wires comprise a first shape memory alloy that is activated to cause the lever to pivot in a first direction and move the piston to the open position and a second shape memory alloy that is activated to cause the lever to pivot in a second direction and move the piston to the closed position.

10. The portable electronic device of claim 8 further comprising a damping member to dampen a transition of a driven member between an open position and a closed position.

11. A shape memory alloy valve assembly comprising:
a piston operable to transition between a first position and a second position to open and close a vent between an interior chamber of an earpiece enclosure and a surrounding ambient environment;
a lever coupled to the piston to drive the transition of the piston;
a pair of shape memory alloy wires coupled to the lever in a parallel arrangement that is operable to cause the lever to pivot and drive the transition of the piston upon application of a current; and
a buckled flexure coupled to the piston to hold the piston in the first position or the second position.

12. The shape memory alloy valve assembly of claim 11 wherein the buckled flexure comprises a first stable state that holds the piston in the first position and a second stable state that holds the piston in the second position.

13. The shape memory alloy valve assembly of claim 12 wherein activation of at least one shape memory alloy wire of the pair of shape memory alloy wires causes a transition of the buckled flexure between the first stable state and the second stable state.

14. The shape memory alloy valve assembly of claim 11 wherein the pair of shape memory alloy wires are each coupled to a separate crimp fixed to the earpiece enclosure, and wherein the separate crimp allows for the current to be applied to a respective one of the pair of shape memory alloy wires.

15. The shape memory alloy valve assembly of claim 11 further comprising a damping member to dampen a transition of a driven member between an open position and a closed position.

16. The shape memory alloy valve assembly of claim 15 wherein the damping member comprises at least one of the pair of shape memory alloy wires actuated to dampen movement of the buckled flexure between a first stable state and a second stable state.

17. The shape memory alloy valve assembly of claim 15 wherein the damping member comprises a damping material coupled to the buckled flexure or a piston contact point surrounding the vent.

Assignees

• Apple Inc

Inventors

• Topliss Richard J
• Gregory Thomas M
• Grinker Scott C
• Walton Christopher J
• Canning Julia C
• Nussbaum Michael B

Classifications

• H04R2460/11

  Aspects relating to vents, e.g. shape, orientation, acoustic properties in ear tips of hearing devices to prevent occlusion · CPC title

• H04R25/652

  Ear tips; Ear moulds (hybrid ear moulds or post-processing thereof for their customisation H04R25/659) · CPC title

• H04R25/02

  adapted to be supported entirely by ear · CPC title

• H04R1/2803

  for loudspeaker transducers · CPC title

• H04R1/1016

  Earpieces of the intra-aural type · CPC title