The following system of instructions is used on the tape of NC machine tools:
In NCmachine tools, the binary systems is used. In this system, the base of the system is 2 and only two characters, 0 and 1, are needed. The binary system is tedious to use in everyday life, but very suitable in the numerical control of machine tools.
The operation of NC machine tools is based on
Operation of NC machine tools is based on prepared programmes which consists of blocks or series of numbers in a coded language.
Conventional NC system is also known as:.
The criteria for selection of a CNC machine tool is
The main function of a spindle in CNC machine is
The main functions of the spindle are: (i) Centering the job or the tool (ii) holding the job or the tool (iii) rotating the job or.the tool
The following device is used for transmitting energy in CNC machine tools:
Conventional lead screw and its nut assembly is not suitable for CNC machine tools because of its lesser power transmitting capacity, lesser accuracy due to backlash and higher frictional forces. To avoid these problems, the recirculating ball screw and nut assembly is used as energy transmitting device in CNC machining
A CNC machine tool consists of a maintaining and repairing system. This system is known as
The method by which the control system calculates the intermediate points and speed of the motor, is known as
What is BLU in numerical control of machining?
Displacement are expressed in part programmes by integers. Each unit corresponds to the position resolution of the axes of motion and will be referred to as the basic length-unit (BLU). The BLU is the smallest length of motion that can be repeatably sensed in the machine
Miscellaneous function for coolant ON is
M 00 - Programme stop
M 01 - Optional stop
M 02 - End of programme
M 03-Spindle on CW
M 04 - Spindle on CCW
M 05 - Spindle off
M 0 8 -C o o la nt on
M 09 - Coolant off
M 17 - Chip conveyor on
M 18 - Chip conveyor off
M 30 - End of tape and tape rewind
M 39 - Auto recycl