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ОглавлениеFigure 2-1 FANUC 30i Machine Tool Controller Courtesy FANUC FA America
1. Become familiar with common CNC machine operator panel functions.
2. Become familiar with common machine control panel functions.
3. Learn common operations performed at the machine control.
4. Learn how to use the controls to input setup data including tool and work offsets.
5. Learn how to use the control to edit programs.
6. Examine some common cases of problem situations and learn how to solve them.
Every CNC Machine Tool has an operation panel and a control panel that provide the interface for the operators and programmers with the machine tool, sometimes referred to as the Human Interface (HMI). By using the operator panel, we physically manipulate the working components of the machine to do what we need; the control panel is where the program data are entered and stored. A thorough understanding of each is necessary for successful CNC machine use. First we will study an example of an operation panel.
The following descriptions for the model shown in Figure 2-2 represent the configuration for a common operator panel. Some differences exist for each manufacturer’s operator panel, but they generally contain the same features. Figure 2-2 shows a panel for a three-axis mill. The panel used for a lathe would be essentially identical except for the axes keys for X and Z only. You should consult the applicable manufacturer manual for detailed descriptions that match your needs. Please note that the Handle (Manual Pulse Generator) is not shown, although it is described in the text. Another common item not shown here are those lathe-specific switches used to change the chucking direction from external to internal. The following sections describe the buttons in order from top-left to right for the three columns of buttons in Figure 2-2.
Figure 2-2 Common Operator Panel Courtesy FANUC FA America
FEEDRATE OVERRIDE
The Feedrate Override dial allows the operator to control the feedrate by adjusting the position of the dial (Figure 2-3). During auto-cycle, when the dial is at the 100 position, the feed will occur at 100% of the programmed value. The control of the work feed is defined by the F-word in the program. You can increase the percentage of the value entered in the program to 120% or decrease it to 0%. This feature provides you the control needed to fine tune feeds. You can also use this feature to control feedrates while using the manual jog mode function. The same is true for the Spindle Override feature, which enables you to override the programmed control spindle speed between 50 and 120%.
Figure 2-3 Feed and Spindle Override Courtesy FANUC FA America
EMERGENCY STOP
The EMERGENCY STOP is the large, red, mushroom-shaped button used to stop machine function when an emergency situation occurs. Examples of such situations are
• overloading of the machine
• the machined part has come loose
• incorrect data in the program or work/tool offsets have caused a collision (crash) between the tool and the workpiece
When this button is pressed, all program-commanded feed rates and spindle revolutions are halted immediately. To recover from an “E-Stop” condition, you must reset the program controller and Home machine axes. To reset the EMERGENCY STOP button, turn it clockwise. It should “pop out” of the depressed condition. Check the monitor for any alarm signals and take note of the Alarm # and description; then eliminate the cause that forced the use of the EMERGENCY STOP button. Press the Reset button to clear all pending commands and Home the machine axes when no interference conditions are present.
Figure 2-4 EMERGENCY STOP Courtesy FANUC FA America
PROGRAM PROTECT
When the Program Protect key switch is in the ON condition (vertical), it prohibits any program changes to be made (Figure 2-5). The condition does not affect work or tool offset adjustments. Some shops set this condition to ON, remove this key, and allow only the programmer or set-up person access to the key. This is especially true in larger shops with multiple shifts and many workers. Some quality programs like AS9100 require that CNC program integrity be insured by locking out access to editing.
Figure 2-5 Program Protect Key Switch Courtesy FANUC FA America
OPERATION PANEL KEY DESCRIPTIONS
This section introduces the function of each individual key/button (Figure 2-6).
PROGRAM SOURCE
On some operation panels, a rotary switch referred to as Mode Select is used instead of the buttons shown in Figure 2-6. This switch includes both automatic (AUTO) and manual operation functions. The position of this switch determines whether the machine utilizes the automatic or the manual control. This switch can also be positioned to allow the entry of data into the control manually (Manual Data Input or MDI) or to make changes to the program through the EDIT mode. For this example, operator panel buttons are used to specify the control or operational mode.
Note: When the buttons are pressed, they are active and remain so until another mode button is pressed that overrides it. In some conditions, multiple Light Emitting Diodes (LEDs) may be lit simultaneously. The LED above the button is lit when the mode is ON and active.
Auto
Pressing this button enables the CNC programs stored in the memory to be executed for automatic operation. When the Cycle Start button is pressed and this mode is active, automatic operation will occur.
Edit
Pressing this button selects the program edit mode. The EDIT mode enables you to enter the part program to control memory via keypad and soft-keys, enter any changes to the program, transfer program data via one of several communication interfaces (RS232, USB, Memory Card, or Ethernet) to or from an offline storage device, or check the program file memory, file locations, and storage capacity.
MDI-Manual Data Input
Pressing the MDI button selects the MANUAL DATA INPUT mode. The MDI mode enables the automatic control of the machine, using information entered in the form of program blocks without interfering with the basic part program. This mode is often used when machining workpiece-holding equipment such as soft-jaws and during setup. It corresponds to single moves (milling surfaces, drilling holes), descriptions of which need not be entered to memory storage.
Figure 2-6 Operator Panel Courtesy FANUC FA America
MDI mode can also be used during the execution of the program. Suppose the program is missing the command M03 S350 needed to turn on the spindle clockwise at 350 r/min, and the End-Of-Block character (;).To correct this omission, press the SINGLE BLOCK button and then the MDI button. Using MDI, you can enter functions M03 and S350 from the control panel keypad followed by the EOB character. Then, enter this command by pressing INPUT on the control panel. Press AUTO to reenter the program auto-cycle mode and then press CYCLE START to continue executing the program from memory. Changes of this sort (program edits) should be saved to overwrite the original program.
Remote
The Remote button is used for DNC (Direct Numerical Control) program operations when the program is too large for the controller memory and is executed (drip-fed) directly from a remote personal computer (PC) via Ethernet or memory card. USB cannot be used for DNC operations.
OPERATION SELECT
The following buttons are related to the automatic operation of the machine. Activating one of these buttons has an effect on the operation.
Single Block
The execution of a SINGLE BLOCK (SINGL BLOCK) of information is initiated by pressing this button to turn it ON. Each time the CYCLE START button is pressed, only one block of information will be executed. This switch can also be used if you intend to check the initial performance of a new program on the machine or when the momentary interruption of a machine’s work is necessary.
Block Skip
When this button is pressed and is active simultaneously with the auto-cycle mode, the controller skips execution of the program blocks that are preceded by the slash (/) symbol and that end with the end of block (;) character. For instance, if a section of the part program or a particular block of the program is not presently needed—but you would like to keep this information for future use—then place the block skip symbol (/) at the beginning of each such block. The BLOCK SKIP button is located on the control panel. If it is activated, then information contained in the blocks that are preceded by the symbol (/) will not be executed.
Example:
N100 G01 X2.810 Y3.256
/N105 X3.253 Y2.864
/N110 X3.800
(Blocks N105 and N110 will be skipped.)
Notes: The symbol (/) should be placed at the beginning of the block. If it is not, then all the information contained in the block preceding the symbol (/) will be executed, while the information following this symbol will be omitted.
If the BLOCK SKIP is in the OFF condition, all blocks [regardless of the symbol (/)] will be executed.
When transferring the program to punched tape or external computer, all program information [regardless of symbol (/)] is transferred.
Opt Stop
When this button is pressed, the OPTIONAL STOP mode is active. The OPTIONAL STOP function interrupts the automatic cycle of the machine if the program word M01 appears in the program. Quite often, function M01 is placed in the program after the work of a particular tool is completed or before a tool change. This enables you to perform chip removal or a routine measurement directly on the machine and, if necessary, make adjustments, and then rerun the same tool to correct inaccuracies.
Teach
If the TEACH button is available, you can use it to create/edit a program, positioning the axes manually by jogging (Teach-in Jog) or handle (Teach-in Handle) mode, and inputting the other required codes while in the MDI or Edit mode. When the Teach mode is used, the movements of the axes are recorded while in either Jog or Handle mode. Machine positions along the X-, Y-, and Z-axes obtained by this manual operation are stored in memory as a program position; they are used to create a program. These movements can then be executed just as with any program. Consult the manufacturer’s operator manual for detailed descriptions on the TEACH button’s proper use. Not all controls have this feature.
Restart
The RESTART button allows you to restart automatic operation at a specific place in the program by entering a desired line sequence number. This sometimes becomes necessary after tool breakage or some type of collision. When the proper data are entered, the control processes through the program until the block entered is reached; it then activates any required modal G, F, D, and H commands. Any needed auxiliary codes (M, S, T, and B) must be entered during the Restart process.
MC Lock
This function is known as MACHINE LOCK. Activating this mode inhibits axis movement on all of the axes. This button is used to check a new program on the machine through the controller. All movements of the tool are locked, while a program check is run on the computer and displayed on the screen. You can observe the position display on the screen; if any program errors are encountered, an alarm will be displayed. This function is especially useful for checking very large programs requiring a long cycle time to complete. This test is normally the first in a series (Program Test, Dry Run, and Single Block) of preliminary actions to be executed before full auto cycle mode is attempted. For any program test, all offsets should be set first. During MACHINE LOCK, all axes are locked. It is possible to unlock selected axes during this mode in order to inhibit axis movement in only one axis. This function is especially useful when inhibiting the Z-axis so that all X, Y movements can still be observed.
Dry Run
When you press the DRY RUN button during automatic cycle, all of the rapid and work feeds are changed to a feed set in the parameters instead of the programmed feed (usually rapid traverse feed rate). In this mode, you can control the feed rate by using the Feed Override switch. Consult the manufacturer manual for specific directions on the use of this function.
DRY RUN is also used to check a new program on the machine without any work actually being performed by the tool. This is particularly useful on programs with long cycle times so you can progress through the program more quickly.
Use caution when using this function. It is NOT intended for metal cutting.
EXECUTION
These three buttons are related to automatic operation of the machine. The first button temporarily stops the operation, the second starts automatic operation, and the last key merely indicates when a program stop is encountered. Their specific functions are described below:
Cycle Stop (Feed Hold)
Pressing the CYCLE STOP button during automatic operation will halt all feed movements of the machine. It will not stop the spindle r/min or affect the execution of tool changes on some machines. When the CYCLE STOP button is pressed, the LED located on the button goes on, and the LED located on the CYCLE START button goes off. This button is used when minor problems are encountered, such as coolant flow direction or when checking DISTANCE-TO-GO during setup. When the problem is remedied, press CYCLE START again to resume automatic cycle operation. It is not recommended using this button to interrupt a cut because the spindle does not stop; therefore, damage to the tool or part may occur. When pressed during the execution of the tapping or threading cycle, CYCLE STOP will take effect after the thread pass or the tap is withdrawn. If the tap breaks during the tapping cycle, the only way to stop the machine is by pressing the RESET button on the controller or the EMERGENCY STOP button.
Cycle Start
The CYCLE START button is used to start automatic operation. Use this button in order to begin the execution of a program from memory. When the CYCLE START button is pressed, the LED located above this button goes on and the active program will be executed to the end.
PRG STOP (Program Stop)
When a Program Stop is commanded in the program by the program word M00, automatic operation is stopped and the LED on this button is turned on. This button does not have an ON/OFF function that affects the program stop condition. It is merely an LED indicator lamp to indicate when a program stop condition is active.
OPERATION
The keys in the Operation section (middle column) are used for manual operation of the machine during setup and initial startup. Their specific functions are described below:
REF (Reference)
Press the REF button to activate it. Then, pressing the X or Z buttons in the positive direction (X, Y or Z for machining centers) causes the machine to return to the Machine Zero position for each axis in relation to the machine coordinate system at the rapid traverse rate (maximum feedrate). The button must be held until the axis indicator LED is lit.
Jog
Pressing the JOG button activates a manual feed mode that allows the selection of manual feed movements along single axes X or Z (X, Y, or Z for machining centers). With the button activated, use the Axis/Direction (+ or –) buttons and the Feed Override dial to move the desired axis at the chosen feed rate. On some controls, Speed/Multiply is a rotary type switch that activates this function.
INC (Incremental)
Press the INC (Incremental JOG) button to activate the JOG mode in incremental steps. When the INC option is selected from the Operation Mode buttons, the incremental step selected by the Speed/Multiply buttons determines the magnitude of the displacement along the chosen axis in the selected direction. When one of the axes directional buttons is pressed and released, the movement will be as follows:
X1 = a movement of .0001 inch or .0025 millimeters (mm)
X10 = a movement of .001 inch or .0254 mm
X100 = a movement of .010 inch or .254 mm
X1000 = a movement of .100 inch or 2.54 mm
The buttons used to select the axis and the direction of movement (+, RAPID, and –) are located in the third column on the fourth row of the Operator Panel, as shown in Figure 2-6 for this controller.
For example, to displace the tool along the X-axis in a positive direction by the value of .010 inch, follow these steps.
• Press the INC button.
• Press the X100 button.
• Press the X button to activate the axis.
• Press the + button once.
Each time the button is pressed, a displacement of the selected value results.
If the JOG mode is selected when one of these buttons is activated, and the selected axis button is pressed and held in, the movement will occur at feed as indicated by the % Traverse Feed override dial.
Handle
Pressing the HANDLE button activates the manual handle feed mode for the selected axis. This handle is known as the Manual Pulse Generator (MPG). Pressing this button places the machine in the HANDLE mode, which enables manual control of axis movements [for X, Y, or Z; or for rotational axes 4 (A), 5 (B), or 6 (C)] by use of the handle after activating their respective axis buttons (Figure 2-7). For instance, press HANDLE, then press X, and then use the Handle to move to the desired position along the X-axis. By turning the handle clockwise, you can move the tool in a positive direction with respect to the position of the coordinate system. By turning the handle counterclockwise, the tool is moved in a negative direction with respect to the position of the coordinate system. The handle contains 100 notches, each of which corresponds to an increment (distance to be moved). Turning the handle, you can feel the displacement from one notch to the next.
To set the magnitude for the distance to be moved, press one of the Speed/Multiply buttons as described in the INC section above.
Caution: If the handle is rotated quickly while the magnitude is set at X100 or X1000, the tool will move at a rapid feed rate and a crash could occur!
When the HANDLE mode is selected, the incremental step selected by the Speed/ Multiply buttons determines the magnitude of the movement along the chosen axis in the selected direction. Each button setting corresponds with the scale of the hand-wheel. One full revolution of the hand-wheel (360°) corresponds to 100 units on the scale. On the button X1, the X means “times” the minimum increment. In manual control, you must use the + or – buttons to identify axis direction as well as to determine the axis of displacement.
Usually, X1 is used when you are precisely dialing-in the zero of the workpiece and when you are determining the tool length offset. For example, if you need to move the machine table with respect to the tool by 1.00” along the X-axis in a positive direction, follow these steps:
• Press HANDLE mode button.
• Press the axis directional button +X.
• Press the SPEED/MULTIPLY button X10.
• Turn the handle one full revolution (100 units) and then check the value of the displacement on the screen. It should indicate a movement of 1.00 inch.
Figure 2-7 Manual Pulse Generator (MPG) HANDLE Courtesy FANUC FA America
X, Y, Z
The X, Y, and Z buttons correspond with each of the linear axes. When one is pressed, that axis becomes active for manual positioning by any of the manual modes.
4, 5, 6
The 4, 5, and 6 buttons correspond with each of the rotary axes. When one is pressed, that axis becomes active for manual positioning by any of the manual modes.
AXIS DIRECTION
+ and −
These buttons are used to select the manual feed axis direction. Pressing these buttons executes movement along the selected axis in the selected direction relative to the machine coordinate system—by Jog feed (or INC feed) or HANDLE—when the corresponding button is set to ON in the jog feed mode (or INC feed mode). The same is true for each of the linear and rotational axis buttons. As long as the button is held, the axis will move at a feed rate determined by the Feed Override dial or INC setting until released.
Rapid
After selecting the desired axis and pressing the Rapid button simultaneously with the + or – button, the machine will move along that axis at rapid traverse until released.
Caution: Prior to activation, be sure the part, fixture, or clamping devices that are in the chosen path are not going to interfere. The axis will move at a rapid feed rate and a crash could occur!
The Operator Panel in Figure 2-2 includes a Feed/Rapid % override dial you can use to control the rapid feed rate. This dial is used to reduce the rapid feed rate (G00). If it is positioned at 100, it corresponds to 100% of the rapid feed rate that the machine can generate. When override buttons are used, they are commonly incremented in steps of 10, 25, 50, and 100%.
SPINDLE
The spindle buttons are used exclusively during the machine’s manual operation for setup functions. The descriptions below explain their specific function:
SPDL CW
By pressing the SPDL CW button while in one of the operation modes REF, JOG, INC, or HANDLE, the spindle will start rotation in the clockwise (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 the control. These keys are also used to enter numerical data and offsets into memory. Many of the keys are used in conjunction with other keys.
Figure 2-12 Alpha-Numerical Keypad Courtesy FANUC FA America
Shift
Because there is not enough space on the control for all keys necessary, the ONG keys have two characters on them. When the letter or symbol indicated in the upper left corner of the key is needed, the operator first presses the SHIFT key, which switches the key to that character. This sequence must be followed each time an alternate letter is needed. The shift key functions the same way as its equivalent on a computer keyboard.
When the Shift key is pressed a special character will be displayed in the left upper corner of the screen. Then the desired (second) character on the key may be entered.
Figure 2-13 SHIFT Key Courtesy FANUC FA America
Cancel
The CANCEL key is used while inputting data in the MDI mode. It is essentially a destructive backspace key and can be used to correct an erroneous entry. Press this key to delete the last character or symbol input to the key input buffer. For instance, when the key input buffer displays:
N5 X12.00 Z
and then the cancel key is pressed, the address Z is erased and:
N5 Xl2.00
is displayed.
Figure 2-14 CANCEL Key Courtesy FANUC FA America
EOB
The EOB key is the END-OF-BLOCK key. When pressed while in the MDI mode, the EOB character (;) is inserted into the program at the cursor location.
Note: The (;) symbol is never part of the program manuscript. When a program is edited offline using a PC, the control system will automatically show the EOB character for each time the “Enter” key is used on the keyboard.
Figure 2-15 End-Of-Block Key Courtesy FANUC FA America
Input
The INPUT key is used for MDI operation and to change the offsets. After the data are entered via the keypad, the INPUT key is pressed. The data are entered into the offset register or the program for execution.
Figure 2-16 INPUT Key Courtesy FANUC FA America
PART PROGRAM EDIT KEYS
These keys are used to enter new program data (INSERT), to make program changes (ALTER/CALC), or to delete program data in memory (DELETE). They are used while editing programs.
Figure 2-17 Program Edit Keys Courtesy FANUC FA America
FUNCTION BUTTONS
The Function buttons correspond to particular display modes (active mode). By pressing any one of these buttons, the display will be switched to the corresponding screen. Then the soft keys may be used to display the needed data.
Figure 2-18 Function Buttons Courtesy FANUC FA America
• Press the POS key to display the position screen.
• Press the PROG key to display the program list screen.
• Press the OFS/SET (Offset/Setting) key to display the screen used to set offsets or adjust parameter settings.
• Press the SYSTEM key to display the system screen.
• Press the MESSAGE key to display the message screen.
• Press the GRAPH key to display the graphics screen.
• CUSTOM1 and CUSTOM2 are keys reserved for the display of conversational macro or C Language Executor.
Cursor
The cursor shows a blinking dash on the display located below the position of a particular address while in one of the Edit modes. On many controls, the cursor highlights the whole word, for example, X7.777.
Cursor Move
In order to navigate through the program, four keys are used to move the cursor.
The right pointing arrow key moves the cursor to the right or in the forward direction. When this key is pressed, the cursor moves only one space each press of the button, in the forward direction. The left pointing arrow key moves the cursor to the left or in the reverse direction. As with the right arrow, when this key is pressed, the cursor moves only one space each press of the button, in the reverse direction.
Figure 2-19 Cursor Move Keys Courtesy FANUC FA America
The downward pointing arrow key moves the cursor downward through the program in the forward direction. Each time this key is pressed, the cursor moves downward one full line. The upward pointing arrow key moves the cursor upward through the program in the reverse direction. Each time this key is pressed, the cursor moves upward one full line.
Use the CURSOR button with the arrow pointing up to change pages in the opposite direction. For example:
O0001
N1 G50 X7.777 Z7.777 S1000
N2 T0100 M39
N3 G96 S600 M03
In this example, the CURSOR is resting below N. By pressing the CURSOR button three times with the right-pointing arrow, the cursor moves below the letter (address) G.
By pressing and holding the CURSOR button with the up arrow, the prompt will move to the first word of program O, which corresponds to the upper limit of cursor movement. Another fast way to return to the program head is to press the RESET key.
By pressing the CURSOR button once, with the arrow pointing down, the cursor will move down one line. If the cursor must be moved over a few or many words, you need not press the button repeatedly. Just press and hold this button down; the cursor automatically jumps one word at a time in the given direction.
Page Up/Down
Usually the length of the program exceeds what the height of the screen will display. The CURSOR move keys can be used to scroll through the program line-by-line. A more effective method to move a large amount is to use the two PAGE keys. Using these keys will advance in the direction selected by the number of lines the screen can display. The last block of a given page becomes the first block of the next page. The PAGE keys allow for scrolling through long programs more effectively.
Figure 2-20 Page Up/Down Keys Courtesy FANUC FA America
PC FUNCTION
This set of function keys are used for PC Functions.
ABC/abc
This key is used to switch from Caps-Lock (all capital letters) to lower case in the same manner as with PC functions.
Figure 2-21 PC Function Keys Courtesy FANUC FA America
Special
The Special Key allows selection of two keys simultaneously from within the NC Guide i software (PC version only). It is used for PC operations where pressing of multiple keys is required.
• Press the Special key.
• Press the required multiple keys in any order. The command will be executed upon final key entry.
Figure 2-22 ABC/abc Key Courtesy FANUC FA America
Figure 2-23 SPECIAL Key Courtesy FANUC FA America
OPERATIONS PERFORMED AT THE CNC CONTROL
The following explanations are for operations considered routine for users of CNC machine tools and are given in their sequence of use. Please note that these procedures are specific to the type of controller depicted here (Fanuc series 0i). The procedures for another type of control may be similar. Be sure to consult the manufacturer manuals specific to your machine tool operation and control panel.
The Machine is Turned On and Homed (Machine Zero)
Turn on the main power switch, and then press the ON Power button on the controller. Most modern machine tools will automatically start-up in the REF/ZERO RETURN mode. This means that before any automatic or manual operation may begin, you must Home the machine first.
If the LED above the REF button in the operation section of the Operator Panel is not lit, press it now to activate the mode.
Using the Axis/Direction keys, press the direction necessary to HOME the machine. Note that many machine tools will have LEDs for each axis that are lit to indicate when that axis is HOMED.
At machine start-up, a common screen displayed is ACTUAL POSITION (ABSOLUTE). If it is not displayed, press the function key labeled POS, then the soft-key ABSOLUTE. The displayed coordinate values represent the relationship between the Workpiece Zero and the Machine Zero (HOME). When the machine is HOME, press the soft-key OPRT, then ORIGIN, and then ALL AXIS to zero each of the coordinate axes.
By pressing the soft keys, you can activate other display screens. For instance, when you press the button ABSOLUTE (which corresponds to position), the digital counter appears on the screen for the X, Y and Z axes, which is the absolute coordinate system for a given workpiece (for turning centers, X and Z will be displayed). The position (POS) function is assigned four display screens and can be found by pressing the soft keys labeled ABSOLUTE, RELATIVE, ALL, and (OPRT). The first screen corresponds to a position change in the ABSOLUTE (ABS) system for X, Y, and Z, as illustrated in Figure 2-24. The second screen RELATIVE (REL) corresponds to position changes in the incremental system for milling machines X, Y, and Z (U and W for turning centers). The third, ALL, gives representation of all four of the displays simultaneously on one screen, as shown in Figure 2-25.
The values listed in the readout for MACHINE represent the distance from Machine Home position.
The DISTANCE TO GO readout is the most significant part of the third display. The coordinates in this quarter of the screen display correspond to the path that will be followed by the tool in order to complete the execution of a given block of information while under automatic operation.
Figure 2-24 Actual Position (Absolute) Screen Courtesy FANUC FA America
Figure 2-25 Actual Position, ALL Screen Courtesy FANUC FA America
Example
N20 G00 Z0.0
N22 G01 Z–12.00 F.015
When block N22 is first read by the control, the value Z–12.000 will appear under the DISTANCE TO GO readout in the upper right corner of the screen. After moving a distance of 1 inch, the value of coordinate Z changes to Z–11.000, and so on. The other displays, ABSOLUTE and RELATIVE, correspond to the first two display screens, but this time they are smaller so that all four displays may fit on one screen. All of the displays may be changed to read in millimeters, with respect to Machine Zero, by changing a machine parameter or by using a G-Code in the program.
The codes listed in the lower left corner of the display pictured in Figures 2-24 and 2-25 are the default G-Codes that are active upon startup of the machine. They are also reinstated by pressing the RESET key.
A Program is Loaded from CNC Memory
The program may be in the program directory, but not activated for automatic operation as shown in Figure 2-26. Follow these steps to activate a program.
1. Press the EDIT button to enter the EDIT mode.
2. Press the PROG function button.
3. Press the DIR soft key.
4. Key in the desired program number from the list. Soft key availability changes to include O SRH.
5. Press the O SRH soft key. The program is now activated.
6. Press the AUTO cycle key to execute the program.
Figure 2-26 Program Folder Screen Courtesy FANUC FA America
A Program is Loaded from an Offline Location
Examples of offline locations include memory cards (PCMIA) and USB drives. Be sure that the output device is ready.
1. Press the EDIT button.
2. Press the PROG function key.
3. Press the DIR soft key.
4. Press the OPRT soft key.
5. Press the DEVICE CHANGE soft key.
6. Select the MEMORY CARD soft key to see available the files or MEM CARD for those on USB.
Select the desired file from the list by keying in the program number and then press the EXEC soft key to activate.
For network drives connected via the Ethernet, if available:
1. Press the EDIT button.
2. Press the PROG function key.
3. Press the DIR soft key.
4. Press the OPRT soft key.
5. Press the DEVICE CHANGE soft key.
6. Select the EMBED ETHER soft key to see available the files from the EMBEDDED ETHERNET HOST FILE LIST.
7. Press the F INPUT soft key.
8. Key in the desired program file name or select desired file from the list by using the cursor move keys.
9. Press the F NAME soft key.
10. Press the EXEC soft key to activate.
A Program Folder is Saved from CNC Memory
1. Press the EDIT button on the operator panel to enter the EDIT mode.
2. Press PROG function key.
3. Press the OPRT soft key.
4. Press the rightmost (continuous-menu key) soft key two times.
5. Press the F OUTPUT soft key.
6. Select F SET or P SET to identify the File name or Program name respectively.
7. Use the keypad to enter the desired program number, preceded by the letter address O, and then press the EXEC soft key.
The program will be saved to the selected offline location media.
8. To save all programs stored in memory, use the same steps above Press O–9999.
A Program is Deleted from Memory
To delete a program from the controller memory, follow these steps:
1. Enter the EDIT mode.
2. Press the PRGRM soft key.
3. Press the DIR soft key.
The program directory will be displayed.
4. Press the OPRT soft key.
5. The screen with one of the soft keys labeled DELETE will be displayed.
6. Enter the program file number (preceded by the letter address O) that you wish to delete.
7. Press the DELETE soft key.
8. Press the EXEC soft key.
The file is deleted.
MDI OPERATIONS
You may input small programs via the keypad at the control. The size of the program, which is limited to 10 lines on the control described in this book, is determined by the parameter setting from the manufacturer. Small programs provide an excellent method of executing simple commands like tool changes, controlling the spindle r/min and its rotation direction, etc. To enter the MDI mode of operations, follow these steps:
1. Press the MDI button on the Operator Panel.
2. Press the PROGRAM function key.
3. Enter the data to be executed by using the methods described later in the section Program Editing Functions.
For the program number, the control assumes O0000 and the data may be entered. Each block ends with the end-of-block (EOB) character (;) so that individual blocks of information can be kept separately. For example:
N1 G50 S1000;
4. Press the EOB function key to insert the semicolon at the end of each line.
5. Press the INSERT key.
6. Press CYCLE START to execute the program information.
If you make a typographical error while entering a given block, you can eliminate it by pressing the CAN key to cancel the error and then reenter the correct value.
You may execute the MDI program as you do with automatic operation. The same control functions apply except that an M30 (tape rewind) command does not return the control to the program head; instead, M99 is used to perform this function. Please refer to the machine tool manufacturer manual for specific instructions.
You can erase an entire program created in MDI mode by the following step:
1. Press the RESET key.
The program will also be erased when the last block of the program is executed by single–block operation.
To perform an individual MDI operation, use the methods described above. For the control described, the display screen is shown in Figure 2-27.
Example 1
1. Turn on the spindle at 500 RPM in the clockwise direction.
2. Key in the following command:
3. S500 M03
4. EOB
5. INSERT
6. CYCLE START
Figure 2-27 Program Screen in MDI Mode Courtesy FANUC FA America
Example 2
Use the following directions to position tool number 5 to the active position on the turret (or to install tool 5 into the spindle on a milling machine). Key in the following commands:
1. T5 M6 (or T0500for a turning center)
2. EOB
3. INSERT
4. CYCLE START
MEASURING WORK COORDINATE OFFSETS: MACHINING CENTER
Following is the procedure for setting the Work Offsets for each workpiece coordinate system G54 to G59. When the values are known or adjustments are needed, you can:
1. Press the OFFSET/SETTING function key.
2. Press the WORK soft key. The WORK COORDINATES setting screen is displayed as shown in Figure 2-28.
Two display screens are needed to handle the six offsets G54–G59. To display a desired page, follow either of these two methods.
Method 1
1. Press the PAGE UP or PAGE DOWN keys until the desired offset is shown.
2. Use the cursor move keys to select the offset number G54–G59 and axis desired.
Alternatively, you can input an offset number 01–06 and press the NO.SRH (number search) soft key. To change the coordinate values of the offsets, use the following method.
Method 2
1. Use the alphanumeric keypad to enter the new value for the offset.
2. Press the INPUT soft-key.
Figure 2-28 Work Coordinates Display Screen Courtesy FANUC FA America
Note: When the INPUT key is used to enter values, the amount entered will replace any amount in the register. When the +INPUT or −INPUT key is used, the existing amount in the offset register will be added or subtracted, whichever applies, by the amount entered into it.
Once the value is entered here, it is the new Workpiece Zero or origin for the workpiece coordinate system. To change an offset by a specific amount, use the alphanumeric keypad to enter the desired value; then press the +INPUT soft key.
Measured Values
Work Offsets can be measured manually by positioning an edge-finding tool to contact with the workpiece zero surface in both X and Y axes sequentially. In this procedure, which is called edge-finding, it is nearly always the perpendicular edges (secondary and tertiary datum) of the workpiece that are referenced.
Follow these steps for measuring Work Coordinate Offsets:
1. Position the machine to HOME.
2. Use the procedure above (steps 1–2) to find the Work Coordinates setting display screen.
3. Use the arrow keys to position the cursor on the offset you wish to use.
4. Press 0 INPUT for the X value.
5. Press 0 INPUT for the Y value.
6. Install an Edge-Finding tool into the spindle using MDI or manually.
7. Start the spindle RPM clockwise at approximately 1000 either manually or by using MDI.
8. Manually position the tool tip edge to contact the workpiece zero surface along the X- or Y-axis.
9. Use the cursor keys and select X or Y; then input the value of the current position related to the workpiece.
10. Press the MEASUR soft key. The absolute position value will be input to the offset.
11. Manually retract the edge-finding tool and repeat the same operation for the remaining axis. In most cases, you will be required to input the difference between the value input and the edge-finder radius (typically 0.100 or 3mm) before automatic operation can be executed.
MACHINING CENTER TOOL OFFSETS
Tool Length Offsets (TLO) are referenced in the program by words beginning with H. The values input into the corresponding T# (LENGTH) GEOM column are needed for to properly position the tool along the Z-axis. When adjustments are needed to compensate for wear, values are input into the WEAR column. Similarly, the Cutter Diameter Compensation (CDC) values are entered on the Offset display register into the (RADIUS) GEOM column and are referenced in the program words beginning with D. These compensations are important for proper radial (X, Y) positioning of the tool. If the values are known, the following sequence can be used to input them into the offset page. When the setup values are known, you may:
1. Press the OFFSET/SETTING function button.
2. Press the OFFSET soft key to display a figure such as Figure 2-29.
3. Use the cursor move keys or page keys to position the cursor to the tool number to be set.
The search method may also be used by entering the tool number whose compensation is to be changed and then pressing the NO.SRH soft key.
Enter the numerical, value of the offset (including sign) and press the INPUT soft key.
To add or subtract from an existing offset value, key in the amount (a negative value to reduce the current value) then press the +INPUT soft key.
Diameter compensation values are input as known after measuring their actual size. Depending on the parameter setting for the specific machine used, the value is entered as either tool diameter or radius. Consult the appropriate manufacturer operation manual for exact conditions.
Measured Values
Tools length offsets can be measured by manually positioning the tool tip to contact the Workpiece Zero surface (Z-axis). This procedure is called “Touching-Off” and is nearly always the top most surface, primary datum of the workpiece. All tools used in the program must have their offsets recorded in the Offset register. If there is not a value in the offset register for a programmed tool, the control will not execute for that tool call, an alarm will occur, and the machine will stop. If a value of zero is in the offset register, the control will accept the zero offset and over travel will result. Conversely, if a value in the offset register is incorrect, the control will execute the tool call as if it was correct and the result could be a collision. For this reason, it is a good idea to delete tool offset data from the offset register when the tool for which it was intended is removed. To do this, input a value of zero for the tool offset register desired.
Figure 2-29 Machining Center OFFSET/GEOMETRY Display Screen Courtesy FANUC FA America
The following steps are needed for the tool offset measuring procedure:
1. Manually position the tool tip to contact the workpiece zero surface (Z-axis).
2. Press the POSITION function key.
3. Select the RELATIVE soft key.
4. Use the alphanumeric keypad and press Z and then INPUT to enter the axis to be measured. The axis should be blinking on the display screen and the soft key options PRESET and ORIGIN shown.
5. Press the ORIGIN soft key and then EXEC. The value in the RELATIVE position display will be changed to 0.0.
6. Press the OFFSET/SETTING function button and then press the OFFSET soft key to display the offset page for tool compensation.
7. Manually position the tool tip to contact the workpiece zero surface (Z-axis).
8. Use the arrow direction keys or the search method described above to position the cursor to the desired offset.
9. Use the alphanumeric keypad and press Z.
10. Press the INPUT soft key.
The relative Z value for the tool offset will be input to the offset register. Repeat for each tool used in the program.
Machining Center Tool Sensor Measuring
On most modern machines, a tool sensor is used as opposed to manually measuring each tool length. When this is the case, all of the programmed tools are manually or automatically positioned to contact the sensor for each tool axis, and the offset values are automatically input into the control. Review the operator manual specific to your machine for exact procedures.
ADJUSTING WEAR OFFSETS FOR MACHINING CENTERS
For machining centers, WEAR offset is assigned in the direction of the Z-axis for tool length compensation. Variations in the X- and Y-axes are compensated by adjusting the values in the (RADIUS) WEAR column. The method for inputting adjustment data is similar to adjusting wear offsets for turning centers.
MEASURING WORK OFFSETS, TURNING CENTER
It is necessary to establish a relationship between the machine coordinate system and the workpiece coordinate system. The following steps are necessary to input the measured values for the workpiece zero to the control’s Work Coordinates offset page.
Measure the Z-Axis Work Coordinate
1. Identify the coordinate system G54–G59 to be used.
2. Manually position the cutting tool and make a cut on the face of the workpiece.
3. Without moving the Z-axis, stop the spindle and move the tool away from the part in the X-axis direction.
4. Identify the distance along the Z-axis from cut surface to the desired zero point.
5. Press the WORK soft key to display the WORK COORDINATES display screen.
6. Position the cursor to the desired workpiece offset to be set.
7. Use the letter address key Z to select the axis to be measured.
8. Use the value of the measurement taken to input the Z-axis work coordinate.
9. Press the MEASUR soft key.
The work coordinate for the Z-axis will be input.
Measure the X-Axis Work Coordinate
1. Manually position the cutting tool and make a cut along the Z-axis to create a diameter on the workpiece.
2. Without moving the X-axis, stop the spindle and move the tool away from the part in the Z-axis direction.
3. Measure the diameter you just cut on the workpiece.
4. Use the value of the measurement taken to input the X-axis work coordinate (enter the diameter).
5. Follow the same procedure for setting the Z-axis work coordinate value as stated above in Steps 6 and 7.
The work coordinate for the X-axis will be input.
TURNING CENTER TOOL OFFSETS
On turning centers, the tool offsets are measured in two directions: Z and X. These values represent the difference between the reference position (Machine Home) of the tool turret and the actual position of a tool tip used as the programmed tool point. The amount of Tool Nose Radius is input on the OFFSET display screen where R is indicated for each tool. An incorrect value here will have an effect on the finished part where tapers and radii are turned. Refer to Part 3, Tool Nose Radius and Tip Orientation (T), for more details.
Measured Values
If the position register commands (G50 for turning and G92 for milling) are used, the values for each tool that have been measured will be input into the program for each tool with the G50 or G92 command.
The more commonly used method today is to input these values into the OFFSET/ GEOMETRY register for each tool (Figure 2-30). Follow these steps to input the measured tool offset value.
Measure the Z-Axis Offset
1. Manually position the cutting tool and make a cut on the face of the workpiece.
2. Without moving the Z-axis, stop the spindle and move the tool away from the part in the X-axis direction.
3. Measure the distance along the Z-axis from the cut surface to the desired zero point.
4. Use this value to input the Z-axis offset for the desired tool number with the following procedure:
a) Press the OFFSET/SETTING function button.
b) Press the OFFSET soft key.
c) Use one of the search methods or use the cursor keys to move the cursor to the offset number to be set.
d) Use the alphanumeric keypad to select the letter address Z.e) Use the alphanumeric keypad to key in the value of the measurement taken.
f) Press the MEASURE soft key.
Figure 2-30 Turning Center OFFSET/GEOMETRY Display Screen Courtesy FANUC FA America
Input the difference between measured value and the coordinate as the offset value.
Measure the X-Axis Offset
1. Manually position the cutting tool and make a cut along the Z-axis to create a diameter on the workpiece.
2. Without moving the X-axis, stop the spindle and move the tool away from the part in the Z-axis direction.
3. Measure the diameter just cut on the workpiece.
4. Follow the same procedure for setting the X offset value as stated above (steps 4. a–f) to input the diameter measured in step 3.
Apply this method for all of the remaining tools used in the program. The offset values are automatically calculated and set.
Turning Center Tool Sensor Measuring
On most modern machines, a tool sensor is used as opposed to machining the diameter and face of the material. In this case, all of the programmed tools are manually or automatically positioned to contact the sensor for each axis and the offset values are automatically input to the control. The operator still must manually enter Tool Nose Radius compensation values in the “R” column of the OFFSET/GEOMETRY register and Tool Tip Orientation “T”. Review the Operator Manual specific to your machine for exact procedures.
Adjusting Wear Offsets for Turning Centers
Wear-Offsets are used to correct the dimensions of the workpiece that change because of cutting tool wear. For a turning center, the X direction offset corresponds to the diameter. For example, if the X wear offset for a tool is .01, an incremental change of minus .01 refers to a decrease of the diameter by .01 and an incremental change of plus .01 refers to an increase of the diameter by .01.
To adjust the WEAR-offsets:
• Press the OFFSET/SETTING button.
• Press the OFFSET soft key. The screen display shown in Figure 2-31 appears.
Examples of Adjusting Wear Offsets
• For the following examples, the operator should display the OFFSET screen for WEAR offsets and the cursor should be positioned to the tool and axis requiring adjustment.
Example 1: The Absolute System
After machining the workpiece shown in Figure 2-32, if the measured external diameter exceeds the value of tolerance (for example, 1.003), enter the offset with a negative sign assigned to the value –.003 in the wear offset by following these steps.
1. Press X
2. Key in –.003
3. Press INPUT+
Then, after machining several more pieces, the diameter increases due to tool wear. If the measured diameter is 1.002, enter the offset as follows:
1. Press X
2. Key in –.005
3. Press INPUT+
Figure 2-31 OFFSET/WEAR Display Screen Courtesy FANUC FA America
Figure 2-32 Example of a Machined Workpiece Used for Adjusting Wear Offsets Courtesy FANUC FA America
Please note that it was necessary to add a value of .002 into the Offset register to the previously entered value of .003. A similar approach is applicable in the direction of the Z-axis.
If the measured length is 1.492, then the value of the offset entered is –.008.
1. Press Z
2. Key in –.008
3. Press INPUT+
A new measured length of 1.494 gives an entered value of the offset of –.006.
1. Press Z
2. Key in –.014
3. Press INPUT+
Example 2: The Incremental System
To gain a better understanding, let us examine identical cases when the incremental coordinate system is used. The measured value is = 1.003.
Offset: U
1. Key in –.003
2. Press INPUT
Following that, the diameter is = 1.002.
3. Press U
4. Key in –.002 (on the screen)
5. Press INPUT (X–.005)
And Z = 1.492
Offset: W
1. Key in –.008
2. Press INPUT
After machining a few pieces, Z = 1.94.
Offset: W
3. Press W
4. Key in –.006 (on the screen)
5. Press INPUT (Z–.014)
TOOL PATH VERIFICATION OF THE PROGRAM
