JPH0554131B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a method for setting a load monitoring state during machining of an NC (numerical control) device equipped with a display device (such as a CRT).

(Technical background of the invention and its problems) When machining with an NC device, the main spindle motor and feed axis motor may become overloaded due to differences in the material and shape of the workpiece, as well as tool wear and breakage. If this condition continues for a long time, the durability of the machine will deteriorate. It would be fine if an operator was always present and could monitor by listening for abnormal sounds, etc., but in the case of unmanned machining, this overload status monitoring is done by NC.
equipment must be used. Therefore, conventionally, the 6th
As shown in the figure, when creating or after creating a machining program, predict the number of sections where overload may occur, and program the monitoring setting mode, such as the "M" code, during the machining program. "On", "off" and limit values are set, and an alarm is issued when the limits are exceeded. However, with the above-mentioned method, it is not only time-consuming to create a program when there are many monitoring sections, but also there are many errors because the M code is specified in the program.Moreover, the settings are based on the predicted machining situation, so it is not reliable. The problem was that monitoring could not be carried out.

(Purpose of the Invention) This invention has been made in view of the above-mentioned points, and involves performing model processing prior to actual processing using an NC device, and monitoring the load fluctuations of the NC device during model processing using a CRT or other means. displayed on a display device,
It is an object of the present invention to provide a load monitoring state setting method for an NC device that allows the load monitoring section and limit value to be set on the screen of the display device.

(Summary of the Invention) The present invention is a numerical control device that detects a load condition during machining using a numerical control device equipped with a display device, and performs load monitoring by comparing the load condition with a set load limit value. This relates to a load monitoring state setting method, which includes a storage means for storing the load state, and a method for storing the load state;
Alternatively, a switching means is provided for switching whether to compare the load limit value and the load state, and model processing is performed prior to actual processing by the numerical control device, and the load state at the time of model processing is stored in the storage means. Monitor the load state by reading out the load state data stored in the storage device after model processing is completed, displaying it as a graph on the display device, and moving the cursor position on the display screen using the keyboard. This allows the section and limit value to be set.

(Embodiment of the invention) Fig. 1 is a block diagram showing an example of means for carrying out the invention, which detects the current values of the main shaft motor (M1) 11 and feed shaft motors (M2 to Mn) 12 to 1n of the NC device. Current detector 1 and the above current detector 1
The A/D converter 2 A/D converts the current value detected by the A/D converter 2, and the continuous rated current value of each of the above motors is set in advance, and the current value digitally converted by the A/D converter 2 is converted into a digital value. A load factor calculator 3 that calculates the load factor (each current value % with the rated current value as 100%) divided by the above rated current value is connected to the above load factor calculator and is operated from the outside to actually It has a switching device 4 that connects to the "b" side during model processing and to the "a" side during model processing. a model machining state memory 5 for storing the data, and a display control unit 6 for displaying the data in the memory 5 on a CRT display device 61.
When setting the load monitoring status, while visually checking the load status screen displayed on the CRT display device 61, move the cursor on the CRT screen to determine the time and load factor limit values corresponding to the monitoring interval. A keyboard 71 for setting the above, and a "monitoring section and limit value memory" 7 for storing the set monitoring section and limit values, and during actual machining,
When the switching device 4 is switched, the current load factor of each motor is compared with the limit value set in the "monitoring section and limit value memory" 7, and the load factor is determined to be the limit value. When it exceeds
The alarm device 81 includes a comparator 8 that issues an alarm.

The operation of this invention will be explained below with reference to the flowcharts of FIGS. 2 and 3 with respect to such a configuration.

When starting the machining program using the NC device (step S1), before starting the actual machining,
First, model processing is performed under the same conditions as in reality (step S2), and the main shaft motor (M1) 11 and feed shaft motor (M2 to Mn) that are to be monitored during model processing are
A current value representing a load state such as 12 to 1n is calculated as the load factor by the load factor calculator 3 via the current detector 1 and A/D converter 2, and is switched by an external operation. It is connected to the model machining state memory 5 via the switching device 4, and the load factor for the time sampled at predetermined time intervals is stored in the model machining state memory 5 (step S3). After finishing the model processing,
A switching device (not shown) is operated from the outside to select one motor from each of the motors 11 to 1n, and the load factor stored in the model machining state memory 5 is displayed on the CRT display device 61 via the display control section 6. (Step S4). FIG. 4 is a diagram showing, for example, the state of the load factor with respect to time of the main shaft motor (M1) 11, which is displayed on the CRT screen as described above. Here, the operator visually confirms a section where the load factor is a large value close to the continuous rated current value (100%) and where it is considered necessary to monitor the load state during actual machining. In addition,
If the CRT display of the load state cannot be displayed on one screen, it can be displayed by dividing the display into time units and switching the screen. and,
Setting the monitoring status (step S5)
The method of setting this monitoring state will be described below with reference to the flowchart in FIG. 3 and the CRT screen display example in FIG. 5.

First, while visually checking the CRT screen, the operator attempts to set the monitoring status (step
S51), operate the cursor keys on the keyboard 71 to move the cursor (indicated by "□" in FIG.
S52), for example, press the "monitoring on" command key provided on the keyboard 71 to command "monitoring on" (step S53). Next, in order to set the limit value of the load factor in this monitoring section, move the cursor "□" on the CRT screen to a predetermined position by operating the cursor keys (step 1).
S54), press the predetermined limit value command key to command the "limit value" L1 (step S55, FIG. 5A). Next, to set the end point of the monitoring interval,
Move the cursor as described above to the monitoring end point T12 (FIG. 5B) (step S56, indicated by "■" in FIG. 5B), press the above-mentioned predetermined "monitoring off" command key, and turn "monitoring off". (step S57).
As a result, "monitoring" T11 of the monitoring section 1
From “monitoring off” T12 and “limit value” L here
1 is automatically set during the NC program.

If there are other monitoring sections (step S58),
By repeating the above-mentioned operations (steps S52 to S58), the monitoring states are set in sequence, and when all monitoring states of all motors are set (steps S52 to S58)
S59), the switching device 4 is operated and switched from the outside, is connected to the display control section 6 and the comparator 8, and actual processing is carried out with the load factors of all the motors 11 to 1n being monitored (step S59). S6).

Here, the load factor of each motor during actual machining in the monitoring interval set above is compared with the "limit value" by the comparator 8, and if the load factor exceeds the "limit value", an alarm device 81 is activated. An alarm is issued. The following operation completes the NC machining with load condition monitoring according to the present invention (step S7).

(Modified example of the invention) In the above embodiment, when there are multiple motors to be monitored, the load operation status during model processing is displayed one by one and the monitoring status is set. display the fluctuation status,
The settings can also be made simultaneously by key operations on the keyboard. In addition, not only does it issue an alarm during actual machining, but it
It goes without saying that the load fluctuation status can be displayed on the CRT screen for visual confirmation.

(Effects of the Invention) As described above, according to the present invention, model processing is performed prior to actual processing, the load state during model processing is displayed on the CRT screen, and the load state on the CRT screen is By moving the cursor to a predetermined position, the operator can set the monitoring range and limit value while visually checking the area, making it easy to operate and accurately grasping the conditions that should be monitored. It has a great effect.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of means for carrying out the invention, FIGS. 2 and 3 are flowcharts showing the operation of the invention, and FIGS. 4 and 5 show examples of CRT screen display according to the invention. FIG. 6 is a diagram showing a process of setting a monitoring state in a conventional NC program. 1... Current detector, 3... Load factor calculator, 4...
...Switching device, 5...Model machining state memory, 7...
...Monitoring interval and limit value memory, 8...Comparator, 6
1...CRT display device, 71...keyboard.

Claims (1)

[Claims] 1. In a load monitoring state setting method in a numerical control device that detects the load state during processing by a numerical control device equipped with a display device and performs load monitoring by comparing a set load limit value and the load state, A storage means for storing the load state and a switching means for switching between storing the load state or comparing the load limit value and the load state are provided, and prior to actual machining by the numerical control device, perform model processing, and store the load state at the time of model processing in the storage means;
After the model processing is completed, the load condition data stored in the storage device is read out and displayed as a graph on the display device, and by moving the cursor position on the display screen using the keyboard, the load condition monitoring interval and limit can be determined. A load monitoring state setting method for a numerical control device, characterized in that a value can be set.