Vibration damping device and design method of the same
A vibration damping device including a supporting member rotating with a rotation element around a rotation center of the rotation element; a restoring force generation member coupled to the supporting member to transfer torque to and from the supporting member and configured to swing with rotation of the supporting member; and an inertia mass body coupled to the supporting member via the restoring force generation member and swinging around the rotation center with the restoring force generation member with rotation of the supporting member, in which the restoring force generation member swings around a swing center so that a relative position with respect to the inertia mass body does not change, and a distance between a center of gravity of the restoring force generation member and the swing center changes with a change in a swing angle of the restoring force generation member with respect to the inertia mass body.
1. A vibration damping device comprising:
a supporting member that rotates integrally with a rotation element, to which torque from an engine is transmitted, around a rotation center of the rotation element;
a restoring force generation member that is coupled to the supporting member so as to transmit and receive torque to and from the supporting member and that is configured to swing about a swing center offset from the rotation center of the rotation element in accordance with rotation of the supporting member; and
an inertia mass body that is coupled to the supporting member via the restoring force generation member and that swings around the rotation center in conjunction with the restoring force generation member in accordance with rotation of the supporting member, wherein
the restoring force generation member swings around the swing center that is set so that a relative position of the swing center with respect to the inertia mass body does not change, and
a distance between a center of gravity of the restoring force generation member and the swing center changes in accordance with a change in a swing angle of the restoring force generation member with respect to the inertia mass body.
2. The vibration damping device according to claim 1 , wherein the distance between the center of gravity of the restoring force generation member and the swing center is increased as the swing angle of the restoring force generation member is increased.
3. The vibration damping device according to claim 2 , wherein
the restoring force generation member includes a reference point that is set to be positioned radially outward of the center of gravity on a straight line including the swing center and the rotation center when the swing angle is zero, and
the reference point of the restoring force generation member swings around the swing center while keeping a distance from the swing center constant.
4. The vibration damping device according to claim 3 , wherein
the restoring force generation member includes a weight main body and a center of gravity adjusting weight that is fixed to the weight main body, and
a center of gravity of the weight main body matches the reference point, and the center of gravity adjusting weight is fixed to the weight main body so that the center of gravity of the restoring force generation member is positioned radially inward of the reference point on the straight line when the swing angle is zero.
5. The vibration damping device according to claim 1 , wherein the distance between the center of gravity of the restoring force generation member and the swing center is decreased as the swing angle of the restoring force generation member is increased.
6. The vibration damping device according to claim 5 , wherein
the restoring force generation member includes a reference point that is set to be positioned radially inward of the center of gravity on a straight line including the swing center and the rotation center when the swing angle is zero, and
the reference point of the restoring force generation member swings around the swing center while keeping a distance from the swing center constant.
7. The vibration damping device according to claim 6 , wherein
the restoring force generation member includes a weight main body and a center of gravity adjusting weight that is fixed to the weight main body, and
a center of gravity of the weight main body matches the reference point, and the center of gravity adjusting weight is fixed to the weight main body so that the center of gravity of the restoring force generation member is positioned radially outward of the reference point on the straight line when the swing angle is zero.
8. The vibration damping device according to claim 1 , the vibration damping device further comprising:
a guided portion that is provided on one of the restoring force generation member and the inertia mass body; and
a guide portion that is formed on the other one of the restoring force generation member and the inertia mass body, and that guides the guided portion so that when the supporting member rotates, the restoring force generation member swings around the swing center and swings along a radial direction of the supporting member and so that the inertia mass body swings around the rotation center, and to which a component force of a centrifugal force acting on the restoring force generation member is transmitted from the guided portion.
9. The vibration damping device according to claim 1 , the vibration damping device further comprising:
a first guide surface provided on the restoring force generation member;
a second guide surface provided on the inertia mass body; and
a coupling member that has a first rolling portion and a second rolling portion integrated with each other, and that is disposed so that the first rolling portion rolls on the first guide surface and the second rolling portion rolls on the second guide surface, wherein
the first and second guide surfaces are formed so that, by having the first rolling portion roll on the first guide surface and the second rolling portion roll on the second guide surface in accordance with rotation of the supporting member, the restoring force generation member swings around the swing center and swings along the radial direction of the supporting member with respect to the rotation center and so that the inertia mass body swings around the rotation center, and
when the supporting member rotates, a component force of a centrifugal force acting on the restoring force generation member is transmitted from the first guide surface to the second guide surface via the coupling member.
10. The vibration damping device according to claim 1 , wherein
the supporting member rotates coaxially and integrally with any rotation element of a damper device having a plurality of rotation elements at least including an input element and an output element, and an elastic body that transmits torque between the input element and the output element.
11. The vibration damping device according to claim 10 , wherein the output element of the damper device is a vibration damping device that is operatively coupled to an input shaft of a transmission.
12. A designing method of a vibration damping device comprising:
a supporting member that rotates integrally with a rotation element, to which torque from an engine is transmitted, around a rotation center of the rotation element;
a restoring force generation member that is coupled to the supporting member so as to transmit and receive torque to and from the supporting member and that is configured to swing about a swing center offset from the rotation center of the rotation element in accordance with rotation of the supporting member; and
an inertia mass body that is coupled to the supporting member via the restoring force generation member and that swings around the rotation center in conjunction with the restoring force generation member in accordance with rotation of the supporting member, in which the restoring force generation member swings around the swing center that is set so that a relative position of the swing center with respect to the inertia mass body does not change, wherein
a trajectory of a center of gravity of the restoring force generation member is set so that a distance between the center of gravity and the swing center changes in accordance with a change in a swing angle of the restoring force generation member with respect to the inertia mass body.
13. The designing method of a vibration damping device according to claim 12 , wherein the trajectory of the center of gravity of the restoring force generation member is set so that the distance between the center of gravity and the swing center is increased as the swing angle of the restoring force generation member is increased.
14. The designing method of a vibration damping device according to claim 13 , wherein
with respect to the restoring force generation member, a reference point that is positioned radially outward of the center of gravity on a straight line including the swing center and the rotation center when the swing angle is zero is set, and
a trajectory of the reference point of the restoring force generation member is set so that the reference point swings around the swing center while keeping a distance from the swing center constant.
15. The designing method of a vibration damping device according to claim 14 , wherein
the restoring force generation member includes a weight main body and a center of gravity adjusting weight that is fixed to the weight main body, and
a center of gravity of the weight main body is matched with the reference point, and the center of gravity adjusting weight is fixed to the weight main body so that the center of gravity of the restoring force generation member is positioned radially inward of the reference point on the straight line when the swing angle is zero.
16. The designing method of a vibration damping device according to claim 12 , wherein
the trajectory of the center of gravity of the restoring force generation member is set so that the distance between the center of gravity and the swing center is decreased as the swing angle of the restoring force generation member is increased.
17. The designing method of a vibration damping device according to claim 16 , wherein
with respect to the restoring force generation member, a reference point positioned radially inward of the center of gravity on a straight line including the swing center and the rotation center when the swing angle is zero is set, and
a trajectory of the reference point of the restoring force generation member is set so that the reference point swings around the swing center while keeping a distance from the swing center constant.
18. The designing method of a vibration damping device according to claim 17 , wherein
the restoring force generation member includes a weight main body and a center of gravity adjusting weight that is fixed to the weight main body, and
a center of gravity of the weight main body is matched with the reference point, and the center of gravity adjusting weight is fixed to the weight main body so that the center of gravity of the restoring force generation member is positioned radially outward of the reference point on the straight line when the swing angle is zero.