ملف متكامل لماكينات CNC بالرسوم المتحركة

CNC means Computer Numerical Control. This means a computer converts the design into numbers which the computer uses to control the cutting and shaping of the material.



HOW TO USE A TYPICAL CNC MACHINE

1.
The design is loaded into the computer which is attached to the CNC
machine. The computer changes the design into a special code (numerical)
that controls the way the CNC cuts and shapes the material.




2.
The material to be shaped is taped on to a block with double sided
tape. This must be done carefully so that it does not come off the block
during machining.




3.
The block is then placed in the vice, inside the CNC. It must be
tightened up carefully. If it is not secure when the machine starts to
cut the material it can come away from the vice. When the machine starts
working, the vice moves up, down, right and left according to the
design.




4.
The guard is placed in position. It protects the machine operator in
case the material is pulled out of the vice by the power of the cutter.
For safety reasons, if the guard is not in position the motor will not
start.




5.
The CNC is turned on and the shape is cut from the material. When the
cutter has stopped the shaped material can be removed from the vice.
Total time - for simple designs - 15 minutes.




In
your own words and with the help of diagrams, explained the stages
involved in the use of a CNC machine such as the one shown above.


تابع

CNC MACHINE - INPUT, PROCESS, OUTPUT


A CNC production facility needs three pieces of equipment:

A Computer.

The
computer is used to draw the design. However, the design is only a
picture and the CNC machine cannot use this to manufacture the product.
The computer software must also convert the drawing into numbers
(coordinates) that the CNC machine can use when it starts to cut and
shape the material.

An Interface.

A
computer cannot be directly connected to a CNC machine. The computer is
connected to an interface. This converts the signals from the computer
to a form that the CNC machine understands. The signals are in the form
of digital signals when they are sent to the CNC machine.

CNC (Computer Numerical Control) Machine.
The
signals from the interface control the motors on the CNC machine. The
signals determine the way the vice moves. The vice moves in three
directions X, Y and Z. (Horizontally, vertically and depth). The signals
also control the speed of the cutting tool.




QUESTION: Draw the systems diagram shown above and explain what happens in the INPUT, PROCESS and OUTPUT sections.

تابعونا ...

POSTER / FLYER DESIGN TO PROMOTE
YOUR CNC PRODUCT


Designing
a promotional leaflet is very important. You may have spent a lot of
time and money developing a product but unless people know it exists, it
will not sell. You are to design a leaflet that will clearly explain
the nature of your product and where it can be purchased. An example can
be seen below.





QUESTION:
List any other information you feel is important - information that
should be mentioned on the leaflet. For example, cost.

تابع

CNC MACHINES AND SAFETY

CNC
machines are very safe to use as they are designed to be as safe as
possible. One of the main advantages of CNC machines is that they are
much safer than manually operated machines. The animation below shows a
Boxford

A3 HSRi² CNC Router with many of its safety features labelled.





1.
Most modern CNC machines are designed so that the cutting tool will not
start unless the guard is in position. Also, the best CNC machines
automatically lock the guard in position whilst the cutter is shaping
material. The guard can only be opened if the cutter has stopped.

2.
It is essential that pupils / students / machine operators receive
‘quality’ instruction before attempting to use any CNC equipment.

3.
CNC routers, used for shaping materials such as woods and plastics,
have built in extraction. Dust can be very dangerous if inhaled and can
also cause eye irritation. The CNC Router shown above has an outlet for
an extraction unit. As the router is fully enclosed, dust cannot escape
into the atmosphere. If an extraction unit is attached the dust is
removed automatically. Most manually operated machine routers have very
limited extraction systems which leave some dust in the air.

4.
The CNC router above has a single phase electrical supply. Most older
machines such as manually operated milling machines and centre lathes
have three phase supplies. A single phase electrical supply can be
‘plugged’ into any available socket. The electrical supply for the
machine comes through a residual circuit breaker (RCB). If an electrical
fault develops the RCB will cut off electrical power immediately.

5.
Single phase CNC machines can be moved more easily because they are
simply unplugged and relocated. Three phase machines are specially wired
by an electrician into the electrical supply and cannot be unplugged.
6.
Most CNC machines work behind a guard or even a closed, transparent
safety door. This means that the operated cannot be hurt by 'flying'
pieces of sharp/hot material. 7.
Commonsense applies to the use of all machines including CNC machines.
Basic safety training regarding working in a workshop and with other
machines applies to CNC machines as well.


QUESTIONS:
1. List the safety features of a typical CNC Machine.
2. Draw a simplified diagram of a CNC machine and point out it's safety features. Explain each feature.