Patent ID: 11884193
Assignee: SUSPENSION SYSTEMS TECHNOLOGIES, INC.
Field: Transport (Mechanical engineering)
Classification: CPC B | IPC B

Claim 24:
25. A passive suspension apparatus for supporting a payload, the passive suspension apparatus comprising:
a base frame, and a supported frame coupled to the base frame, the supported frame configured to be disposed vertically a neutral height above the base frame when a payload having a payload weight is disposed on the supported frame, the suspension apparatus configured to support relative displacement in a generally vertical direction between the supported frame and the base frame from a minimum height to a maximum height, the supported frame being coupled to the base frame via:
a scissor linkage, the scissor linkage comprising two crossed scissor arms pivotably coupled together about a central pivot, each of the two crossed scissor arms extending from the base frame to the supported frame, each arm being free to rotate relative to the other arm as the supported frame and the base frame move closer to and farther away from each other;
a coarse suspension device coupling the base frame to the supported frame, the coarse suspension device configured to oppose relative displacement between the base frame and the supported frame in the generally vertical direction, the coarse suspension device not being directly coupled to the scissor linkage, the coarse suspension device being adjustable to support the payload at the neutral height;
a fine suspension device coupled to one of the base frame and the supported frame, the fine suspension device configured to provide a horizontal damping force in response to a first force applied to the base frame in the generally vertical direction, wherein the horizontal damping force is configured to vary in a non-linear manner such that:
the horizontal damping force provided by the fine suspension device when the first force applied to the base frame is in an upward direction is different from
the horizontal damping force provided by the fine suspension device when the first force applied to the base frame is in a downward direction; and

a mechanical assembly operably coupled to the fine suspension device, the mechanical assembly configured to convert the horizontal damping force into a second force applied to the supported frame in a generally vertical direction opposite to the first force applied to the base frame,
wherein the passive suspension apparatus comprises only passive components.