Method and apparatus for mitigating static loads in components connecting multiple structures
An apparatus and method are described where one or more pre-stressed spring elements are disposed between two structures to mitigate or cancel the effect of static loads applied to a component connecting the structures. The apparatus and methods may be used, for example, to reduce the adverse impact of static loads on the performance of top-mounts in a suspension system of a vehicle.
1. A top-mount assembly for attaching a suspension component to a vehicle body, comprising:
a top-mount bracket;
a strike plate configured to be attached to a rod of the suspension component;
a first set of one or more first spring elements in contact with the strike plate, wherein each first spring element applies a first force to the strike plate in a first direction; and
a second set of one or more second spring elements in contact with the strike plate, wherein each second spring element applies a second force to the strike plate in a second direction that is opposite the first direction,
wherein, when the strike plate is disconnected from the rod of the suspension component, the first set of one or more first spring elements and the second set of one or more second spring elements are configured to position the strike plate in a pre-stressed position,
wherein, when the strike plate is connected to the rod of the suspension component and exposed to a predetermined rod force, the first set of one or more first spring elements and the second set of one or more second spring elements are configured to position the strike plate in a loaded position, and
wherein the loaded position is more centrally located within the top-mount bracket along an axis substantially parallel to the first and second directions than the pre-stressed position.
2. The top-mount assembly of claim 1 , wherein the suspension component is selected from the group consisting of a passive damper, an active damper, a semi-active damper, and a magnetorheological damper.
3. The top-mount assembly of claim 1 , wherein the predetermined rod force is a force applied by a piston rod of the suspension component under static conditions.
4. The top-mount assembly of claim 1 , wherein at least one of the first set of one or more first spring elements and the second set of one or more second spring elements comprises a resilient material interposed between the top-mount bracket and the strike plate.
5. The top-mount assembly of claim 4 , wherein the resilient material comprises an elastomer.
6. The top-mount assembly of claim 1 , wherein the predetermined rod force is between 700 and 2000 Newtons.
7. The top-mount assembly of claim 1 , wherein the predetermined rod force is between 800 and 900 Newtons.
8. The top-mount assembly of claim 1 , wherein the loaded position of the strike plate is approximately equal to a neutral position of the strike plate.
9. The top-mount assembly of claim 1 , wherein the second set of one or more second spring elements has a compliance greater than a compliance of the first set of one or more first spring elements.
10. The top-mount assembly of claim 9 , wherein the compliance of the second set of one or more spring elements is greater than the compliance of the first set of one or more first spring elements by at least a factor of 2.
11. An actuator assembly for a vehicle, the actuator assembly comprising:
a hydraulic actuator comprising a damper body and a rod protruding from the damper body; and
a top-mount comprising:
a strike plate operatively connected to the rod of the hydraulic actuator;
a top-mount bracket at least partially surrounding the strike plate;
a first set of one or more first spring elements in contact with the strike plate, wherein each first spring element applies a first force to the strike plate in a first direction; and
a second set of one or more second spring elements in contact with the strike plate, wherein each second spring element applies a second force to the strike plate in a second direction that is opposite the first direction,
wherein, when the strike plate is disconnected from the rod of the hydraulic actuator, the first set of one or more first spring elements and the second set of one or more second spring elements are configured to position the strike plate in a pre-stressed position,
wherein, when the strike plate is connected to the rod of the hydraulic actuator and exposed to a predetermined rod force, the first set of one or more first spring elements and the second set of one or more second spring elements are configured to position the strike plate in a loaded position, and
wherein the loaded position is more centrally located within the top-mount bracket along an axis substantially parallel to the first and second directions than the pre-stressed position.
12. The actuator assembly of claim 11 , wherein the hydraulic actuator is selected from the group consisting of a passive damper, an active damper, and a semi-active damper.
13. The actuator assembly of claim 11 , wherein the predetermined rod force is a force applied by the rod of the hydraulic actuator under static conditions.
14. The actuator assembly of claim 11 , wherein at least one of the first set of one or more first spring elements and the second set of one or more second spring elements comprises a resilient material interposed between the top-mount bracket and the strike plate.
15. The actuator assembly of claim 14 , wherein the resilient material comprises an elastomer.
16. The actuator assembly of claim 11 , wherein the predetermined rod force is between 700 and 2000 Newtons.
17. The actuator assembly of claim 11 , wherein the predetermined rod force is between 800 and 900 Newtons.
18. The actuator assembly of claim 11 , wherein the loaded position of the strike plate is approximately equal to a neutral position of the strike plate.
19. The actuator assembly of claim 11 , wherein the second set of one or more second spring elements has a compliance greater than a compliance of the first set of one or more first spring elements.
20. The actuator assembly of claim 19 , wherein the compliance of the second set of one or more spring elements is greater than the compliance of the first set of one or more first spring elements by at least a factor of 2.