Very often linkages or mechanisms used in practice share the same
kinematic principles. Parametrized linkages give finer control over
link dimensions. But you might want to reuse simple linkages as
building blocks of more complicated mechanisms. LinkageDesigner
supports this kind of "copy and paste" linkage by providing
the AttacheLinkage function, which allows you to "glue" two
or more linkages together to achieve more complex mechanisms with
minimal effort. AttacheLinkage is especially useful in
defining mechanisms with replicate-base mechanisms, like an engine.
To illustrate this linkage definition technique, we will build a
V engine with four pistons.
Whitworth's Quick Return Mechanism
The Whitworth quick return mechanism converts rotary motion into
reciprocating motion, but unlike the crank and slider, the forward
reciprocating motion is at a different rate than the backward stroke.
At the bottom of the drive arm, the peg only has to move through a few
degrees to sweep the arm from left to right, but it takes the
remainder of the revolution to bring the arm back. This mechanism is
most commonly seen as the drive for a shaping machine.