Programming of CNC Machines. Ken Evans
(CW) direction. The spindle rev/min is adjusted by using the Spindle Override dial. When set at 100%, the spindle will rotate the last r/min commanded in the program. The spindle command is retained and will restart upon pressing the SPDL CW button. When the machine is first started, there has been no value established for the r/min. Therefore, if one of these buttons is pressed while in the modes listed above, an alarm will result. An r/min must be input via MDI or by activating the program. From that point on, as long as the machine is not turned off, the r/min will be activated at the last commanded value when one of these buttons is pressed.
SPDL STOP
Pressing the SPDL STOP button stops spindle motor rotation while in one of the operation modes listed above. However, pressing this button will NOT stop the spindle while in any of the Automatic execution modes.
SPDL CCW
Pressing the SPDL CCW button is exactly the same as pressing the SPDL CW except that the spindle will start rotation in the counterclockwise (CCW) direction.
COOLANT
Although not shown on this operator panel, there are buttons that control coolant flow during manual or automatic operation. In some cases, there is a manual switch to turn coolant on and off.
The control panel described here is quite typical of the control panels used on CNC machines. The control panel switches and buttons may be distributed differently on the panel for each individual machine; however, the purpose and function of each switch and button remains the same. Some control panels are equipped with additional buttons or switches not shown here. Definitions and applications of these buttons or switches can be found in the manufacturer instruction manuals for the machines.
The control panel is located at the front of the machine and is equipped with a CRT and with various buttons and switches, as illustrated in Figure 2-8.
PC integrated controls are commonly identified with the lower case letter i after the controller series number, i.e., 0i. They allow you to use third party software like Excel, etc., and to connect to the Internet for diagnostic purposes and remote access. Modern machine tools are equipped with Ethernet connectivity to your company’s network (some offer wireless), thereby offering unlimited part program and tool file storage with easy access via Windows-based operating systems.
For this controller, there is an access door on the upper left side of the display that contains a memory card slot and USB port. Some older controls still have a 3.5 floppy disk and possibly a PCMCI (Portable Computer Memory Card Interface) slot. All of these methods are used as a file storage medium and transfer.
There are two alpha key arrangements. QWERTY (Figure 2-1) matches standard keyboards while the ONG style, which is more popular for 0i, is shown in Figure 2-8. A detailed description for the use of each button and its purpose on the control panel are presented in the following sections.
POWER-ON AND POWER-OFF
Located in the lower left hand corner of the control in Figure 2-8, the Power-On and Power-Off buttons are used to activate/deactivate the power to the control. Press these buttons to turn CNC power ON and OFF. The ON button is white in color and when it is ON, the key is lit. The OFF button is typically black in color and when the power is turned OFF to the control, the key is lit. At startup of the main power to the machine, the OFF button is lit. On older machines, these keys will be green and red in color respectively. Directly above these buttons are the Operation Selection buttons which are described in the same-named section of this chapter. Path Select is used for multi-path controls. For this controller, it is inactive.
Figure 2-8 Common Control Panel Courtesy FANUC FA America
Note: The control is always turned ON after turning on the MAIN POWER switch, which is located on the door of the control system, typically at the back or side of the machine. The control is always turned OFF before the MAIN POWER switch is turned OFF.
CRT Display
The CRT is the display screen on which all the program characters and data are shown. Sizes vary from around 9 inches to approximately 15 inches. Displays are color, monochrome, or liquid crystal displays (LCD). FANUC displays (shown here) offer 8.4, 10.4, and 15-inch screens.
Reset
Pressing the RESET button resets or cancels an alarm; it can also be used to cancel an automatic operation. An alarm can only be cancelled if its cause has been eliminated.
When the reset button is pressed during automatic operation, all program-commanded axis feeds and spindle revolutions are cancelled. The program will return to its starting block when this button is pressed.
Figure 2-9 RESET Button Courtesy FANUC FA America
Help
Pressing the HELP key gives the operator access to help screens on how to operate the machine functions such as MDI key operation, or details related to an alarm that has occurred in the control.
Figure 2-10 HELP Button Courtesy FANUC FA America
SOFT KEYS
The soft keys have numerous functions, depending on the applications selected along with other keys. The specific functions of the soft keys are displayed in the box HELP above the key at the bottom of the CRT screen, as shown in Figure 2-11. The purpose of the soft keys is to minimize the use of dedicated keys on the control panel.
Figure 2-11 Controller Soft Keys Courtesy FANUC FA America
The selection soft keys are the first four rectangular keys under the CRT. By pressing one of them, the function selections that belong to that key appear. These selection choices are called chapters. If the soft key for a target chapter is not displayed, you must press the continuous menu key located at the right end of the soft keys (sometimes referred to as next menu). In some cases, there are additional chapters that can be selected from within a chapter. When the desired screen is displayed, press the soft key under operation selection (OPRT) on the display in order to manipulate the data. To reverse through the chapter selection soft keys, press the return menu key located at the left end of the soft keys.
The machine ORIGIN register can be reset by use of the soft keys. READ soft keys let you enter the program to memory from a punched tape or other storage medium; the PUNCH soft key allows program readout from memory to one of several options of storage medium.
The general screen display procedure is explained above; however, the actual display procedure varies from one screen to another. For details, see the description of individual operations.
Note: The operator should consult the manufacturer’s manual for more specific detailed instructions on the use of the soft keys.
ADDRESS AND NUMERIC KEYS (ALPHA-NUMERICAL KEYS)
This keypad of letters, numbers, and symbol characters is used to input data while writing or editing programs at