Stabilizer bar assembly and vehicle including the same

1. A stabilizer bar assembly, comprising:

a left bar;

a right bar;

an outer cylinder member connected to a first one of the left bar and the right bar;

an inner cylinder member provided inside the outer cylinder member and configured to enable relative rotation with the outer cylinder member, and the inner cylinder member being connected to the other one of the left bar and the right bar; and

a torsion spring configured to provide rotational stiffness to the inner cylinder member relative to the outer cylinder member.

2. The stabilizer bar assembly of claim 1 , wherein the torsion spring has a first end directly or indirectly coupled to the outer cylinder member and wherein the torsion spring has a second end directly or indirectly fixed to the inner cylinder member.

3. The stabilizer bar assembly of claim 2 , further comprising a shaft fixed to the inner cylinder member, wherein the second end of the torsion spring is fixed to the shaft.

4. The stabilizer bar assembly of claim 2 , further comprising a compression sheet fixed to the outer cylinder member, wherein the first end of the torsion spring is pressed by the compression sheet.

5. The stabilizer bar assembly of claim 1 , further comprising:

a stopper protruding inwardly from an inner diameter of the outer cylinder member; and

a stopper groove provided in an outer diameter of the inner cylinder member, wherein the stopper is inserted into the stopper groove.

6. The stabilizer bar assembly of claim 5 , wherein the stopper and the stopper groove are configured such that the stopper is caught by the stopper groove due to the relative rotation between the inner cylinder member and the outer cylinder member, and such that a rotational force between the outer cylinder member and the inner cylinder member is transmitted via contact of the stopper with the stopper groove.

7. The stabilizer bar assembly of claim 5 , wherein a first gap is between a stopper side surface of the stopper and a stopper groove side surface of the stopper groove in a rotational direction.

8. The stabilizer bar assembly of claim 1 , further comprising:

a compression sheet fixed to the outer cylinder member and by which a first end of the torsion spring is engaged; and

a shaft fixed to the inner cylinder member and to which a second end of the torsion spring is fixed.

9. The stabilizer bar assembly of claim 8 , wherein the shaft is configured to have a length in a longitudinal direction of the inner cylinder member, and wherein the first end of the torsion spring is inserted into the shaft.

10. The stabilizer bar assembly of claim 9 , wherein the torsion spring comprises a plurality of torsion spring portions that are sequentially inserted along the longitudinal direction of the shaft,

wherein the first end of the torsion spring comprises a set of outer ends of the plurality of torsion spring portions,

wherein the set of the outer ends of the plurality of torsion spring portions intersect each other and extend in alternating left and right directions to form a space therebetween the set of the outer ends along the longitudinal direction, and

wherein a portion of the compression sheet is inserted into the space therebetween the set of the outer ends to engage the first end of the torsion spring.

11. The stabilizer bar assembly of claim 10 , wherein the compression sheet has a compression protrusion extending therefrom, and wherein the compression protrusion protrudes into the space therebetween the set of the outer ends, such that the compression protrusion engages the set of the outer ends.

12. The stabilizer bar assembly of claim 1 , wherein the stabilizer bar assembly is configured such that as the outer cylinder member and the inner cylinder member initially rotate relative to each other, the torsion spring generates a primary roll stiffness due to elasticity of the torsion spring.

13. The stabilizer bar assembly of claim 12 , wherein the stabilizer bar assembly is configured such that after the outer cylinder member and the inner cylinder member initially rotate relative to each other and as the outer cylinder member and the inner cylinder member continue to rotate relative to each other beyond a transition rotation point, torsion of the left and right bars generates a secondary roll stiffness, wherein the secondary roll stiffness is greater than the primary roll stiffness.

14. The stabilizer bar assembly of claim 1 , further comprising:

a stopper of the outer cylinder member; and

a stopper groove in an outer diameter of the inner cylinder member, wherein the stopper is inserted into the stopper groove, and wherein the stabilizer bar assembly is configured such that as the outer cylinder member and the inner cylinder member rotate relative to each other, the torsion spring generates a primary roll stiffness at least until a first gap between a stopper side surface of the stopper and a stopper groove side surface of the stopper groove is closed.

15. The stabilizer bar assembly of claim 14 , wherein the stabilizer bar assembly is configured such that after the stopper side surface of the stopper contacts the stopper groove side surface of the stopper groove and the first gap is closed, through continued rotation of the outer cylinder member and the inner cylinder member relative to each other, a secondary roll stiffness greater than the primary roll stiffness is implemented by torsion of the left bar and the right bar.

16. A stabilizer bar assembly for a vehicle, comprising:

a first bar extending along a first partial width of the vehicle;

a second bar extending along a second partial width of the vehicle;

an outer cylinder member rotationally fixed to the first bar;

an inner cylinder member rotationally fixed to the second bar, wherein at least part of the inner cylinder member extends within the outer cylinder member;

a torsion spring member having a first end rotationally fixed to the inner cylinder member, and the torsion spring member having a second end configured to engage the outer cylinder member, wherein the torsion spring member is configured to provide spring force between the inner cylinder member and the outer cylinder member;

a first rotation stopper on the outer cylinder member; and

a second rotational stopper on the inner cylinder member, wherein the stabilizer bar assembly is configured such that as the outer cylinder member and inner cylinder member initially rotate relative to each other, the torsion spring member generates a primary roll stiffness due to elasticity of the torsion spring member, and wherein the stabilizer bar assembly is configured such that after the outer cylinder member and the inner cylinder member initially rotate relative to each other and as the outer cylinder member and the inner cylinder member continue to rotate relative to each other beyond a transition rotation point at which the first rotation stopper engages the second rotational stopper, torsion of the first and second bars generates a secondary roll stiffness, wherein the secondary roll stiffness is greater than the primary roll stiffness.

17. The stabilizer bar assembly of claim 16 , wherein the torsion spring member comprises:

a first set of torsion springs arranged in a first orientation;

a second set of torsion springs arranged in a second orientation, wherein the first orientation is opposite of the second orientation, and wherein the first set of torsion springs are alternated with and interleaved with the second set of torsion springs along a width direction of the vehicle; and

a protrusion member extending along the width direction of the vehicle between the first set of torsion springs and the second set of torsion springs.

18. The assembly of claim 17 , wherein the first rotation stopper extends inward towards the inner cylinder member from an inner surface of the outer cylinder member, and wherein the second rotational stopper is a stopper groove in an outer surface of the inner cylinder member, and wherein the first rotational stopper is inserted into the stopper groove of the second rotational stopper.