From DT Online
Levers of any of the 3 Classes may be combined such that the load of one lever is the effort applied to another.
This can be done to increase Mechanical Advantage (especially where operating space is restricted) or to increase movement as with a piano key mechanism for example.
Features and Uses
|Bench Shears - a 4-Bar Linkage is used. Hand force is applied to one crank. The upper tool blade is fixed to the other crank.||Foot Operated Shearing Machine - the blue slider carrying the red upper cutter is driven by a 6-bar mechanism. The sheet is clamped before sheared by a slider crank mechanism of brown eccentric shaft. The runway of the green slider is on the blue slider. The orange lower cutter is fixed to the machine base. The red upper cutter has an inclined cutting edge to cut with reduced force using a skewed slicing action.|
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