JPH0630011B2 - Numerical control Machining restart control method - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION AND PRIOR ART The present invention allows a numerical controller to automatically perform a series of operations during a fixed cycle, that is, by programming a specific code and a minimum movement command. The present invention relates to a numerical control machining restart control method for restarting the machining, which is interrupted due to some cause such as a power failure or a stop operation during a fixed cycle in which a sequence operation is generated to control the machine to perform the machining.

In the case of machining with a numerically controlled machine tool, if machining is interrupted for some reason during machining, in order to restart the machining, in the conventional numerical controller, the NC program must be restarted from the beginning or by operator's operation. It was necessary to return to the block at the time of processing interruption and restore various modal data that determines the processing conditions. These restoration processes are the same even when the stop point, that is, the restart point, is in the fixed cycle, resulting in wasted time and error in the restoration work.

Object of the Invention The object of the present invention is to restart the machining when the machining is interrupted during a fixed cycle used for drilling such as drilling and tapping in a numerically controlled machine tool or turning for performing repetitive sequence operations. Another object of the present invention is to provide a numerical control machining restart control method capable of automatically determining a process and restarting correct numerical control machining under the same conditions as before interruption.

Embodiment Hereinafter, one embodiment of the present invention will be described with reference to the drawings by taking a tapping cycle as an example of a fixed cycle.

FIG. 1 is a block diagram of a main part of a numerical controller for implementing the method of the present invention, in which 1 is a microcomputer and 2 is N.
A CMOS memory that stores the C processing program, which may be configured by command data and a tape reader that reads the command data. Further, 3 is a non-volatile memory capable of writing and reading, 4 is a manual data input device, 5 is its interface circuit, 6 is an axis control circuit, 7 is a servo amplifier, 8 is a servo motor, 9 is a position detector, and 10 is a position detector. Is a current value counter composed of non-volatile elements. The axis control circuit 6,
Servo motor amplifier 7, servo motor 8, position detector 9
For convenience of explanation, the present value counter 10 is shown with only one axis.

FIG. 2 is an explanatory diagram of a tapping cycle which is a fixed cycle indicated by a G code G84. Fixed cycle G
The 84 tapping cycle command is commanded in the following format.

G84 X x Y y Z z R r F f P p When such a command is issued, the following series of sequence operations are automatically performed inside the numerical controller.

Move to the drilling start position (point I) of the x and y coordinate position values x and y input by the command G84. In addition, Z
Since the axis coordinate position is modal, it is specified at the coordinate position instructed in the previous block.

The approach amount r input by the command G84 is fast-forwarded in the Z-axis direction and moved to the point R.

Cutting is performed at the set value f of the feed rate F up to the value z of Z input by the command G84, that is, up to the hole bottom.

The dwell operation for the set value p is performed at the bottom Z point.

Spindle reverse rotation Pull out at the feed rate of set value f to point R.

Spindle forward rotation Fast return to the drilling start position (point I).

In addition, in the fixed cycle, FIG. 2 G90 or G
Whether the positioning is performed in the absolute mode or the incremental mode indicated by 91,
The moving positions such as the drilling start position I point, the approach point R point, the hole bottom Z point and the like are stored as absolute values in registers in the respective memories 3.

Next, the processing method of the present invention when the processing is interrupted and restarted during such a fixed cycle will be described in detail with the processing flow of FIG.

Now, the numerically controlled machine tool is moving the axis control circuit 6, the servo amplifier 7, and the servo motor 8 according to the NC program stored in the CMOS 2 shown in FIG.
Therefore, when the G84 code is read in the above format, the numerical control apparatus performs the processing of the above steps to, but at this time, the microcomputer 1 sets the x, which is the point I of the drilling start position given by the above command or the like. The coordinate positions of the y and z axes, the position of the approach point R point, and the Z axis coordinate position of the hole bottom Z point (in this embodiment, since the tap is made in the Z axis direction, the Z axis coordinate position may be used) are the absolute values. Each register in the memory 3 is stored as a value. Then, the processes of the above steps 1 to 3 are performed. However, when the machining is interrupted due to a power failure or the like in the middle of the process and then restarted, the cycle start button provided on the machine side or the manual data input device
When a restart command is input from, the microcomputer 1 reads the Z-axis value SP of the current value counter 10 which counts up and down by the output pulse of the position detector 9 and stores the current tool position (P _{1 in} FIG. 3). ). In addition,
This value SP indicates the tool stop position when the machining is interrupted. Then, the drilling start position I in the memory 3
The value of the position I (Z) is read from the register storing the Z-axis coordinate position I (Z) of the point, and the Z-axis coordinate position I of the point I is read.
(Z) is compared with the tool stop position SP (P _{2 in} FIG. 3), and if they are the same, the pointer (1) indicating the step is stored in the step counter in the memory 3 (P _{3 in} FIG. ₃ ). When the counter stores the step, the process is restarted from the step. That is,
X of point I, positioning the drilling start position I point to move the tool to a value of the register that stores the y-axis coordinate position and thereafter performs the normal processing (FIG. 3 P _4). Next, the tool stop position S
When the Z-axis coordinate position I (Z) of the point P and the point I are not equal, SP of the tool stop position and the value of the register storing the position of the approach point R point are compared (P _{5 in} FIG. ₃ ). If the tool stop position SP is larger (note that the tapping in this embodiment is processed in the minus direction of the Z axis), the tool is stopped at the step shown in FIG. Therefore, the pointer (2) of the step is stored in the step counter (P _{6 in} FIG. 3), and the process is restarted from the step. That is, the approach point R position is fast-forwarded to the value of the register which is stored as an absolute value (P _{7 in} FIG. 3). If the tool stop position SP is smaller than the approach point R, then the tool stop position SP and the hole bottom position Z are compared with the stored value of the register (P _{8 in} FIG. 3). As shown by, since it is smaller than the R point and not the Z point, it indicates that the tool is stopped during the step. Therefore,
Pointer (3) indicating the step in the step counter
Is stored, and the process is restarted from the step (P ₉ , P _{10 in} FIG. 3). That is, tapping is performed at the set value of the feed speed f up to the value of the register in which the hole bottom position Z is stored as an absolute value, and thereafter, the fixed cycle processing after the step is performed and the normal processing is performed. If the tool stop position SP and the hole bottom position Z are equal, the step pointer (5) is stored in the step counter and the machining is restarted from the step (P ₁₁ and P _{12 in} FIG. 3).

Although the tapping cycle is shown as the fixed cycle in the above-mentioned embodiment, the present invention can be applied to a fixed cycle such as drilling, boring, and machining.

EFFECTS OF THE INVENTION When machining is interrupted in a fixed cycle in machining with the numerically controlled machine tool of the present invention, the tool stop step is divided by comparing the tool stop position with the end point position of each step in the fixed cycle. Since the processing is restarted from this step, the processing can be interrupted, and when restarted, it can be restarted quickly, and the numerical control device automatically performs restart processing, preventing mistakes due to human operation. Is something that can be done.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a numerical controller for implementing the method of the present invention, FIG. 2 is an explanatory diagram of a tapping cycle,
FIG. 3 is a processing flow of an embodiment of the present invention. 4 ... Manual data input device, 9 ... Position detector.

Front Page Continuation (72) Inventor Motoaki Yoshino 3-5-5 Asahigaoka, Hino-shi, Tokyo Within Fanatsuku Co., Ltd. (56) Reference JP-A-57-60401 (JP, A) JP-A-57-60402 ( JP, A) JP 57-147709 (JP, A)

Claims (1)

[Claims] 1. In a fixed cycle machining process by a numerical controller, each register stores a command position of each step of the fixed cycle and a counter which stores a current position of a tool, so that each of the registers is restarted after machining interruption. And the value of the counter are compared, the step of the fixed cycle in which the tool is stopped is indexed, and the machining is automatically restarted from the indexed step. method.