Compound Lever: Difference between revisions

Revision as of 15:44, 27 August 2016

Description

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

Common examples of Compound Lever applications include: nail clippers, bolt cutters, bench shears, 'aviation' type tinsnips, bass drum pedal and mechanical typewriter mechanisms.

Animations

Examples from Nguyen Duc Thang's YouTube Channel 2100 Animated Mechanical Mechanisms

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.

DT Online Buyers' Guide

Simple Frames and Linkages can be explored using Construction Kits such as those listed below.

More varied models can be constructed using the materials listed at Truss Bridge Models or Stripwood Technology Materials and tools described in Stripwood Technology Tools.

Click top left to enlarge


Viga Wooden Construction Set	Straws and Connectors	Construction Engineering Blocks	K'Nex Education Group Set	Engino STEM Construction Set	Lego Duplo Tech Machines Set	Lego Education Core Set	Meccano Easy Construction Box	Fischertechnik Universal Building Kit

@@ Line 24: / Line 24: @@
 | [https://youtu.be/zLLgQCJ4vSQ '''Bench Shears'''] - a '''[[Four Bar Chain|4-Bar Linkage]]''' is used. Hand force is applied to one crank. The upper tool blade is fixed to the other crank.
 | {{#ev:youtube|zLLgQCJ4vSQ|200x200|right||frame|loop=1&autoplay=1&playlist=zLLgQCJ4vSQ}}
-| [https://youtu.be/pyGNgP6ZNvA '''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 inclining cutting
+| [https://youtu.be/pyGNgP6ZNvA '''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.
 | {{#ev:youtube|pyGNgP6ZNvA|200x200|right||frame|loop=1&autoplay=1&playlist=pyGNgP6ZNvA}}
 |}