Sunday, April 5, 2009

BASIC ELECTRONICS

Semi Conductor Theory

According to this theory there are three types of materials with respect to its resistance.

Conductor

It is stated as follow
The materials is called conductor which has a resistance of (10)^-6ohm-cm It is a small valve of resistance

Copper, Gold, Silver and Iron are the some examples of conductor

Semi-Conductor

It is stated as follow
The materials is called semi-conductor which has a resistance of (10)^2 ohm-cm It is a medium valve of resistance.
Germanium, silicon and carbon are the some examples of semi-conductor

Insulator
It is stated as follow
The materials is called Insulator which has a resistance of (10)^6 ohm-cm It is a high valve of resistance

Paper, Glass, Rubber, Wood and Oil are the some examples of insulators

Shell or Orbit

It is the path in which the electrons are moved or circulate around the nucleus of the atom



Valance Shell

Last shell of an atom in which electrons are moved is known as valance shell.




Valance Electrons

The no. of electrons which are present in valance shell of the atom is known as valance electron


Energy bands

It is the group of the energy levels who are very closer but separate to each other.

Types of energy bands

There are three types of energy bands

1). Filled Band
2).Valance band
3).Conduction band
Explanation of these bands is following there

Filled Band

A band in which minimum no. of free electrons are present is called filled band. This band is situated above on the valance band. In this band the electrons have low energy.

Valance Band

A band in which a large no. of free electrons is present is called valance band. This band is situated above on the conduction band. In this band the electrons have high energy.

Conduction Band

A band in which a large no. of free electrons is present is called valance band. This band is full fill with free electrons. This band situated below the valance band. In this band the electrons have very high energy.

Diagram




There are two main types of semi-conductor materials

1). Intrinsic semiconductor
2). Extrinsic semiconductor
contact.


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Thursday, March 26, 2009

Semiconductor

The materials whose characteristics are between those of conductor and insulator is known as semiconductor in other words the materials which have high resistance than conductor and less resistance than that of insulator is called semiconductor.
With respect to valance band those materials are called semiconductor in which only four electrons are present in his last orbit germanium, silicon and carbon are examples of semiconductor

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Insulator

The materials which have very few free electrons are called insulator. In other words these materials are not conduct easily. Those materials which have eight valance electrons are known as good insulator. Glass, mica, rubber and plastic is the some examples of insulator. With respect to valance band those materials are called insulator in which greater than four electrons are present in his last orbit.

Electric Circuits And Networks

Conductor:
The materials which have many free electrons are called conductor. In other words these materials are conduct easily. Those materials which have only one valance electron are known as good conductor. For example copper, silver and gold.

With respect to valance band those materials are called conductor in which less than four electrons are present in his last orbit.

Thursday, December 25, 2008

data input keys

Data Input Keys
Note tot data input keys
Each data input key runs several functions (number,address character (s)).Repeated pressing of the key switches to the next function automatically








Function Keys
Note for function keys
At the PC keyboard the function keys can be displayed as softkeys with the key F I2
.

Sunday, December 14, 2008

CONTROL KEYBOARD,DEGITIZER LAYOUT

RESET .................... Cancel an alarm, reset the CNC (e.g. interrupt a program), etc.
CURSOR ................ Search function, line up/down, program call-up

PAGE ...................... Page up/down
ALTER .................... Alter word (replace)

INSERT ................... Insert word, create new program
DELETE .................. Delete program, block, word
/,# EOB ................... Skip block, End of Block
CAN ......................... Delete program, block, word
INPUT ..................... Word input, data input
OUTP START ........ Start data output

POS ......................... Indicates the current position
PRGRM .................. Edit and display of the program, input of the MDI data; display of command value in automatic mode
MENU OFSET ....... Setting and display of offset value, tool and wear data, varia‑ bles
DGNOS PARAM ... Setting and display of parameter and display of diagnostic data
OPR ALARM .......... Alarm and message display
AUX GRAPH .......... Graphic display

Saturday, November 29, 2008

PANEL SCREEN OF CNC MACHINE

THE SCREEN

1, Display of feed and spindle speed correction
2, Display of speed and actual tool
3, Display of operation mode
4, Display of softkey functions
5, Entry key
6, Return to main menu (Fl on PC-keyboard)
7, Soft keys(keys;F3 to F7 on PC-keyboard)
8, Extension of menu line (key F11 on PC-keyboard)

THE MAIN OPERATION MOD

INFORMATION



AUTOMATIC:

Used to work off a part programme. The control work off
the programmed blocks one after the other and includes 1the programmed corrction vaiue(tool,zero point shift)


JOG:

Conventional work with the machines by means of the direction keys and the corresponding function keys, respectively;e.g. spindle on/off, swivel tool turret, etc.


MDI-AUTOMATIC:

In this operating mode programme directions can be loaded into the intermediate memory of the control(manual Data Input) and worked off.The programme blocks are deleted
automatically after work-off.Example of application; check of zero point shift, positioning of tools for a-sample cut.

REFPOINT

Ia used for the zero adjustment of the system of units of' the machine. By approaching the reference point the control and the machine are "synchronized"
The reference point has to' be approached;
- After switch-on/a power failure of the machine
- after a collision and and an overload of the feed motor, respectively.

INC FEED 1 .... INC FEED 10 000

In this operating mode the slides can be traversed by means of the direction keys by the path increment selected (unit =um ).
Example of application; positioning of tools during measurement, scratching on raw material.

Friday, November 28, 2008

LEARNING OF G COD

Survey of commands G- functions

SCOPE OF COMMANDS





GOO.......... Rapid traverse
G01.......... Linear interpolation in working feed

G02.......... Circular interpolation, Clock wise
G03.......... Circular interpolation, Counter ciock wise
G04.......... Dwell, active block by block
G20......... Roughing cycle, Single
G21......... Threading cycle,Single

G24......... Facing cycle, Single
G28.......... Approach reference point
G33.......... Thread cutting
G40......... Deselction cutter radius compensation
'G41.......... Cutter radius compensation left
G42......... Cutter radius compensation right
G70.......... Dimension in inch
G71.......... Dimension in millimeter
G72......... Finishing cycle
G?3.......... Longitudinal turning cycle
G74......... Facing cycle
G75......... Patternlrepetition
G76......... Deep hole drill/face grooving cycle
G77......... Grooving cycleG78 Thread cutting cycle
G80........... Deselection drilling cycle
G83........... Drilling cycle
G84........... Tapping cycle
G85........... Drilling cycle with high excavation speed
G90.......... Absolute value programming
G91.......... Incremental value programming
G92........... Set coordinate zero point/ speed limitation
G94........... Feed in mm/min
G95 .......... Feed in mm/rev
G96........... Constant cutting speed
G97........... Constant speed
G98.......... Return to start plane
G99......... oReturn to withdrawal plane