Turntable With Press; Linear Feed - fischertechnik Profi Pneumatic II Manual De Instrucciones

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either the inside or the outside.
Answer:
See Construction Manual page 21 .
While doing so, you have to pay attention that every valve is
returned to the middle position after operation. Otherwise the
door cannot be operated by means of the second valve.

3.3 Turntable with press

Machines with which one is able to produce or assemble components in
factories are quite frequently pneumatically driven. Our machine consists
of a turntable and a press. You will build the model as is described in the
Construction Manual on page 22.
(Illustration_Turntable)
Each of the two functions will be operated with a specific valve. The
turntable is designed so that it continues to pulsate (clocks forward) with
every extension of the cylinder without having to turn back during retraction
of the cylinder.
Experiment:
The two functions "turning" and "pressing" shall be executed in
succession. How many components can you process in one minute?
Operate the valves successively and do the necessary timing.
Are you able to do this so quickly that the compressor "runs out of
breath"; i.e. that it cannot produce enough air to operate the cylinder
at this speed?
Exercise:
In reality such systems are not actually controlled by hand. How does
one actually control such systems?
14
Exercise:
The disadvantage of
our door is that you
can only open and
close it from one side.
Now you will install a
second valve so that
the door can be opened and closed from
Answer:
Instead of the hand valves, valves which can be opened or closed by
means of an electric impulse are used. These (valves) receive their
impulses from a programmable control mechanism called "SPC"
(Stored Program Control). The programmer provides input concerning
the sequence in which the valves are to be operated, stores (saves)
all of the information — and, "lo and behold", the system functions
without someone having to constantly open and close the valves.
We will deal with how you can automate such systems with fischertechnik in
Chapter 5.

3.4 Linear feed

In the previous model the turntable was always "clocked" a step further
during operation of the valve. The possibility also exists to gradually clock
the motion forward in a straight line. For information concerning construction
of the "Linear Feed" model, see the Construction Manual on page 26.
You can see that the linear feed requires much more effort to realize than
the turntable. Now we need three pneumatic cylinders.
Exercise:
Can you imagine how such a feed mechanism is utilized in reality?
Answer:
For instance, in sawmills for transporting logs which will be sawn off
at a specific length.
Of course, in real systems the function would also be automated. But
our manual operation is completely sufficient for understanding how this
principle functions.