Cnc axis and motion nomenclature

CNC MACHINES IN SHORT

1. NAME :- KRUNAL K. CHAMPANERI SUBJECT :- CAM ENROLL NO:- 156050319004 BRANCH:- MECHANICAL (SFI) COLLEGE :- B&B INSTITUE OF TECHNOLOGY CNC AXES AND MOTION NOMENCLATURE

2. Different CNC Machine tools A typical 3-axis CNC Gantry Machine Moves above the stationary work piece (part) Spindle moves at 90 0 in/out of the part A typical CNC lathe machine tool Slides along the part Multi-axis CNC Machines Rotary motion of spindle Stationary CNC machine, but tool is allowed to move in different direction

3. Axis and Motion Nomenclature Cartesian System Machine coordinate system is described based on Cartesian system A Cartesian coordinate system is a  coordinate system  that specifies each point uniquely in a plane by a pair of  numerical coordinates , which are the signed distances to the point from two fixed perpendicular directed lines, measured in the same unit of length.  Each reference line is called a  coordinate axis  or just  axis of the system, and the point where they meet is its  origin , at ordered pair (0, 0). 

4.  The coordinates can also be defined as the positions of the perpendicular projections of the point onto the two axes, expressed as signed distances from the origin . In this system, use Right-hand Rule to designate the primary axis of the machine tool.

5. Right Hand Rule of Coordinates Right Hand Rule of Coordinates, hold the thumb, forefinger and middle finger at 90 degree, to each other. Thumb (x-axis), Forefinger (y-axis), and Middle finger (z-axis), each finger points +ve direction of motion of the CNC tool motion of the CNC tool. In 3-axis CNC milling machine, the longest travel slide represents the x-axis, each finger points to +ve direction of motion of the CNC tool, the z-axis points into the spindle

6. CNC Lathe Axes Nomenclature

7. 3-Axis CNC Milling Machine

8. Positioning System Two type of positioning system Absolute system Incremental system

9. Absolute System Absolute positioning always tells the controller where to send the cutter  relative to the  origin. The controller always knows where the cutter currently is located, so it can calculate the distance and direction it must send the cutter to arrive at the desired destination.

10. Incremental Positioning Incremental positioning always tells the controller where to send the cutter  relative to the cutter's current location.

11. References http:// faculty.etsu.edu/hemphill/entc3710/nc-prog/nc-02-01.html. https:// en.wikipedia.org/wiki/Cartesian_coordinate_system.

12. Thank You