Ear muff attachment having dual axis of rotation

1. An ear muff attachment assembly, comprising:

a housing with a protrusion that forms a first lever seat and a second lever seat on the housing and;

an ear muff;

an arm comprising a first end region and a second end region, wherein the first end region comprises a first lever seat engaging structure, extending from the arm, and a second lever seat engaging structure, extending from the arm;

wherein the first lever seat engaging structure, when engaging the first lever seat, forms a first axis of rotation for the arm, and wherein the second lever seat engaging structure, when engaging the second lever seat, forms a second axis of rotation for the arm;

wherein the arm is rotatable about the first axis of rotation between a first position and an intermediate position, and about the second axis of rotation between the intermediate position and a second position, and wherein the protrusion interacts with the arm such that the protrusion is in between the first and second lever seat engaging structures as the arm moves between the first position, the intermediate position, and the second position; and

wherein a spring is positioned within the housing and contacts a spring retention feature of the first end region on a first spring end and contacts the housing on a second spring end, and wherein the spring exerts a first spring force between the first position and the intermediate position that acts to return the arm to the first position, and a second spring force between the intermediate position and the second position that acts to return the arm to the second position, and wherein the spring retention feature comprises a recess.

2. The ear muff attachment assembly of claim 1 , wherein the first lever seat engaging structure and the second lever seat engaging structure are positioned on the arm to form a recess on the arm that receives the protrusion, wherein the protrusion is a shaped such that it engages the first and second lever seat engaging structures, respectively, in each of the first and second positions.

3. The ear muff attachment assembly of claim 1 , wherein the first and second lever seat engaging structures are positioned on the arm such that a groove is formed, wherein the groove receives the protrusion.

4. The ear muff attachment assembly of claim 1 , wherein the first and second axes of rotation are parallel.

5. The ear muff attachment assembly of claim 1 , wherein the spring is a spring selected from the group consisting of a coil spring, leaf spring, and wire spring.

6. The ear muff attachment assembly of claim 1 , wherein the ear muff is in an active position configured to cover a user's ear when the arm is in the first position and the ear muff is in a standby position away from a user's ear when the arm is in the second position.

7. The ear muff attachment assembly of claim 6 , wherein the arm exerts a force (F) at the second end region, and a first maximum force exerted between the first position and the intermediate position (Fmax1) is greater than a second maximum force (Fmax2) exerted between the intermediate position and the second position.

8. The ear muff attachment assembly of claim 1 , wherein the ear muff is removably attached to the second end of the arm.

9. The ear muff attachment assembly of claim 1 , wherein the ear muff is adjustably attached to the second end of the arm.

10. An ear muff attachment assembly, comprising:

a housing comprising a first lever seat defining a first axis of rotation and a second lever seat defining a second axis of rotation and a protrusion between the first and second lever seats;

an arm comprising a first end region and a second end region, the first end region comprising a first lever seat engaging structure and a second lever seat engaging structure that are each rotatably engageable with the first and second lever seats, respectively, and wherein the first and second lever seat engaging structures are positioned on the arm on either side of a recess that receives the protrusion, and wherein the engagement between the first and second lever seat engaging structures and the first and second lever seats allow the earmuff attachment assembly to move around the first and second axes of rotation, wherein the second axis of rotation is parallel to the first axis of rotation, and the second end region comprises an ear muff; and

a spring within the housing that is attached to a spring retention feature on the first end region of the arm within the housing, on a first spring end, and is attached to the housing on a spring second end, and wherein the spring retention feature is a recess that receives the spring;

wherein the arm is rotatable about the first axis of rotation between a first position and an intermediate position, and about the second axis of rotation between the intermediate position and a second position, and wherein the spring is rotatably engageable such that it exerts a first spring force between the first position and the intermediate position that acts to return the arm to the first position, and exerts a second spring force between the intermediate position and the second position that acts to return the arm to the second position.

11. An ear muff device, comprising:

a helmet; and

a first earmuff attachment assembly and a second ear muff attachment assemblies, each attached to the helmet, each of the first and second ear muff attachment assemblies comprising:

an earmuff housing comprising a first lever seat defining a first axis of rotation and a second lever seat defining a second axis of rotation, wherein the first and second lever seats are positioned, respectively, above and below a protrusion on the earmuff housing;

an arm comprising first and second end regions, the first end region comprising a first lever seat engaging structure that rotatably engages the first lever seat, and a second lever seat engaging structure that rotatably engages the second lever seat, and wherein the engagement between the first and second lever seats and the first and second lever engaging structures causes one of the first or second earmuff attachment assemblies to rotate about the protrusion on the first and second axes of rotation, wherein the second axis of rotation is parallel to the first axis of rotation, and the second end region comprises an ear muff; and

a spring attached to the earmuff housing on a first spring end and contacts, on a second spring end a recess in the first end region of the arm within the housing;

wherein the arm is rotatable about the first axis of rotation between a first and an intermediate position such that the arm rotates about the protrusion in the first lever seat between the first and intermediate position, and about the second axis of rotation between the intermediate position and a second position such that the arm rotates about the protrusion in the second lever seat between the intermediate and the second position, and wherein the spring exerts a first spring force between the first position and the intermediate position that acts to return the arm to the first position, and a second spring force between the intermediate position and the second position that acts to return the arm to the second position.

12. The ear muff device of claim 11 , further comprising an adapter attachable to the helmet and having a slot configured to slidably receive a mating feature of the housing.

13. The ear muff device of claim 11 , wherein the first position the ear muff is in an engaged position configured to cover a user's ear and the second position is a second engaged position configured to position the ear muff over a user's ear.