Elastic member structure and linear vibration motor using the same
An elastic member structure includes: a loop type inner plate; a loop type outer plate having the same center as the loop type inner plate; and a plurality of spiral elastic plates connected to the loop type inner plate and the loop type outer plate and having given elasticity, wherein the loop type outer plate includes a plurality of first areas having areas connected to the ends of the plurality of spiral elastic plates and a plurality of second areas formed between the plurality of first areas and the outer size of each first area of the loop type outer plate is greater than the outer size of each second area thereof.
1. An elastic member structure comprising:
a loop type inner plate ( 110 );
a loop type outer plate ( 120 ) having the same center as the loop type inner plate ( 110 ); and
a plurality of spiral elastic plates ( 130 ) connected to the loop type inner plate ( 110 ) and the loop type outer plate ( 120 ) and having given elasticity,
wherein the loop type outer plate ( 120 ) comprises a plurality of first areas (A 1 ) having areas connected to the ends of the plurality of spiral elastic plates ( 130 ) and a plurality of second areas (A 2 ) formed between the plurality of first areas (A 1 ) and the outer size of each first area (A 1 ) of the loop type outer plate ( 120 ) is greater than the outer size of each second area (A 2 ) thereof,
wherein the loop type outer plate ( 120 ) has a plurality of concave grooves (H) formed on the inner peripheral surface of each first area (Al), each concave groove having a given radius of curvature, and
wherein a minimum angle (θ 1 ) at which each first area (Al) of the loop type outer plate ( 120 ) is formed around the center (O 1 ) of the loop type inner plate ( 110 ) is the same as an angle formed between a first imaginary line (L 1 ) connecting the center (O 1 ) of the loop type inner plate ( 110 ) with a center point (C 1 ) of the concave groove (H) and a second imaginary line (L 2 ) connecting the center (O 1 ) of the loop type inner plate ( 110 ) with a center point (C 2 ) formed on the end of an outer slot (H′) formed on each spiral elastic plate ( 130 ).
2. The elastic member structure according to claim 1 , wherein the plurality of spiral elastic plates ( 130 ) are connected to the loop type inner plate ( 110 ) in such a manner as to be equally spaced apart from each other around the center (O 1 ) of the loop type inner plate ( 110 ).
3. The elastic member structure according to claim 1 , wherein the loop type inner plate ( 110 ), the loop type outer plate ( 120 ), and the plurality of spiral elastic plates ( 130 ) are made of the same material as each other.
4. A linear vibration motor ( 1000 ) having an internal space formed by means of a casing ( 20 ) and a bracket ( 10 ) to generate vibrations with an electromagnetic force generated between an oscillator ( 40 ) and a stator ( 30 ), comprising an elastic member structure ( 100 ) disposed on the bracket ( 10 ) to support the oscillator ( 40 ), the elastic member structure ( 100 ) comprising:
a loop type inner plate ( 110 ) coming into contact with the oscillator ( 40 );
a loop type outer plate ( 120 ) having the same center as the loop type inner plate ( 110 ) and coming into contact with the bracket ( 10 ); and
a plurality of spiral elastic plates ( 130 ) connected to the loop type inner plate ( 110 ) and the loop type outer plate ( 120 ), wherein the loop type outer plate ( 120 ) comprises a plurality of first areas (Al) having areas connected to the ends of the plurality of spiral elastic plates ( 130 ) and a plurality of second areas (A 2 ) formed between the plurality of first areas (Al) and the outer size of each first area (Al) of the loop type outer plate ( 120 ) is greater than the outer size of each second area (A 2 ) thereof,
wherein the elastic member structure ( 100 ) further comprises a plurality of concave grooves (H) formed on the inner peripheral surface of each first area (Al), each concave groove (H) having a given radius of curvature, and
wherein the elastic member structure ( 100 ) has a minimum angle (θ 1 ) at which each first area (Al) of the loop type outer plate ( 120 ) is formed around the center (O 1 ) of the loop type inner plate ( 110 ), the minimum angle (θ 1 ) being the same as an angle formed between a first imaginary line (L 1 ) connecting the center (O 1 ) of the loop type inner plate ( 110 ) with a center point (C 1 ) of the concave groove (H) and a second imaginary line (L 2 ) connecting the center (O 1 ) of the loop type inner plate ( 110 ) with a center point (C 2 ) formed on the end of an outer slot (H′) formed on each spiral elastic plate ( 130 ).
5. The linear vibration motor according to claim 4 , wherein the loop type outer plate ( 120 ) of the elastic member structure ( 100 ) is weldedly contacted with the bracket ( 10 ), and the minimum number of welded points (P) of the loop type outer plate ( 120 ) to the bracket ( 10 ) is equal to the number of spiral elastic plates ( 130 ).