摘要 |
A suspension unit includes a lower frame, an upper frame vertically movably mounted on the lower frame, and two link mechanisms disposed on respective sides of the upper and lower frames for connecting them to each other. Each of the two link mechanisms includes a parallel link mechanism having two arms extending generally parallel to each other and a pantograph-shaped link mechanism having a plurality of arms. The suspension unit further includes two permanent magnets each fixedly mounted on one of the upper and lower frames with like magnetic poles opposed to each other, a metallic spring engaged with one of the pantograph-shaped link mechanisms, and a shock absorber engaged with the other of the pantograph-shaped link mechanisms that has spring properties. With such construction, vibration below a predetermined amplitude is absorbed by the spring properties of the other of the pantograph-shaped link mechanisms with the shock absorber not operated.
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