JP3180801B2 - Numerically controlled machine tools - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerically controlled machine tool capable of quickly performing auxiliary command processing.

[0002]

2. Description of the Related Art In recent years, a numerical controller built in a computer (hereinafter, referred to as a numerical controller)
2. Description of the Related Art Machine tools (hereinafter, referred to as numerical control machine tools) using CNCs have become widespread, and automation and labor saving in the processing field have been promoted. The numerically controlled machine tool includes a CNC, a high-power sequence circuit, and a machine tool. The high-power sequence circuit is located between the CNC and the machine tool and performs various auxiliary tasks. Depending on the size of the machine, the high-power sequence circuit has conventionally been formed by 200 to 300 relay circuits. Just as the numerical control device (hereinafter, referred to as NC) has shifted from the wiring logic NC to the CNC, the programmable controller (hereinafter, referred to as PC) using a microprocessor has become the mainstream in the high-power sequence circuit from the relay circuit.

The PC includes a general-purpose PC and a built-in P dedicated to CNC.
There is C. A general-purpose PC is used for a machine tool that has hundreds of tools and an autoloader and requires a complicated sequence and input / output signals, but a built-in PC is used for most machine tools.
Is enough. In a built-in PC for a lathe or a small machining center, an independent microprocessor is not particularly prepared for the PC, and the PC function can be exhibited by utilizing the remaining power of the microprocessor for the CNC. In this case, the number of components for the PC is extremely small, and a product excellent in both reliability and cost can be realized.

Since a PC with a built-in CNC is built in the CNC, there is also an advantage that a space for installing the PC on the machine side is not required. Transfer of data between the built-in PC and the CNC does not require a special driver / receiver and requires only a common bus (or equivalent).
Is about half the number of input / output points required when a general-purpose PC is used.

[0005] Various settings such as timers and counters for the PC, status display and alarm message display can be performed using the operation panel of the CNC, and no additional operation panel is required. FIG. 10 is a schematic configuration diagram of a CNC machine tool using a CNC with a built-in PC.
In the figure, 10 is a CNC unit and 20 is a machine tool unit. The CNC unit 10 includes an NC unit 1, a PC unit 2, and an input / output circuit 3. The NC unit 1 includes an operator and a CNC.
Consisting of a man-machine control unit 4 for controlling by a man-machine interface with a machine tool, an auxiliary command control unit 5 for controlling auxiliary commands such as an M command, an S command, and a T command, and an axis movement control unit 6 for controlling a servo axis. Is done.

The PC section 2 is a part for storing a sequence program, and is a sequence control device (not shown) having the same structure as a computer, and includes a CPU, a program storage device mainly comprising semiconductor memories such as ROM and RAM, and the like. It is configured. The input / output circuit 3 is an interface portion with the machine side and is composed of a driver and a receiver.
3. Connected to the spindle amplifier 15 and the like.

The machine tool section 20 includes an operator and a CNC.
N which is the center of man-machine interface of machine tools
There is a C operation panel 11, which is usually composed of a CRT device, numeric keys, and the like, and displays data of the NC unit 1 on the CRT device and inputs data from the numeric keys.

[0008] In addition, the machine operation panel 12 is mainly for the operator to manually operate the machine tool, the high-power circuit 13 is for controlling the actuator of each machine section 14, and the like.
The spindle amplifier 15 controls the spindle motor 16 and the speed control unit 17 controls the 18 feed motors.

The original work of a machine tool is processing such as cutting and grinding, but there are many auxiliary works for performing this processing. For example, mounting / removing a workpiece, starting / stopping a spindle motor, turning on / off a cutting oil, selecting a tool, and the like. These auxiliary tasks are processed by the PC unit 2 upon receiving an auxiliary function signal (M command), a tool selection signal (T command), and the like sent from the NC unit 1.

FIG. 11 is an explanatory view of a conventional interface for an auxiliary function signal. The NC unit 1 sends an M code signal (M11 to M28) of two digits of BCD and a code reading signal (hereinafter referred to as MF) to the PC unit 2, and the sent code signal is decoded by the PC unit 2 and becomes necessary. Actuator is driven in a predetermined sequence, and the commanded operation is performed.

When the operation is completed, a completion signal (hereinafter referred to as FIN)
Is written to the NC unit 1. The NC unit 1 thereby turns off the MF. Subsequently, the FIN is turned off and the M code signal is turned off, and the process proceeds to the next block command. A time chart of this operation is shown in FIG.

FIG. 13 is a diagram showing a flow from creation of a machining program to inspection of a workpiece. The programmer 101 creates an NC machining program while looking at the machining drawing 100 (step 102). The machining program is created in a normal EIA format, an automatic program mounted on a CNC which has been frequently used in recent years, or an off-line CAM. Numeral 103 denotes an NC machining program created in this way.

When the creation of the machining program 103 is completed, the machining program 103 is checked (step 104). This can be performed, for example, by displaying the trajectory of the machining path on the screen, since many recent CNCs are capable of graphic display and the like. If the machining program 103 is deemed to be correct, the machine tool is actually moved by idle cutting, and the machining program 103 is checked while confirming the operation of the machine tool (step 105). If it is considered that cutting can be performed correctly, a work is actually attached and trial processing is performed (step 106). If the cutting can be performed correctly, a full-scale cutting process is started (step 107).
The workpiece is inspected as needed (step 108). If a defect of the machining program is found in each of the steps 104 to 108, the machining program 103 is corrected (step 109), and the necessary steps of steps 104 to 108 are checked again.

[0014]

Since the conventional numerically controlled machine tool is constructed as described above, even for auxiliary commands which do not need to wait for completion, the next is to wait for the completion of each auxiliary command. Since the process proceeds to the step, there is a first problem that the processing time is wasted.

In order to solve this problem, Japanese Patent Application Laid-Open No.
As disclosed in Japanese Patent No. 89506, a method of processing the next block without waiting for the FIN is described for the M command that does not need to wait for the completion of the M command, but simply waits for the FIN of the M command. If the processing of the next block is performed without doing so, a problem occurs in the following case, and the M command cannot be executed correctly.

That is, the next block is executed without waiting for the FIN of the first M command, and when the second M command is present in the next block, the second M command is output to the PC as it is. Since the PC is executing the first M command, the second
This M command is ignored or causes a trouble inside the PC such as interrupting the first M command and executing the second M command. The prior art described above does not particularly describe changing the interface with the PC, and if the interface with the PC remains unchanged, the PC issues the next M command while processing the M command. No output is allowed. In addition, the auxiliary command (MS
Regarding the T command, a method for performing the completion processing between the CNC and the PC at a high speed has been studied (Japanese Patent Laid-Open No. 63-2).
0707, and JP-A-64-3707).
However, the inventions disclosed in these publications also only speed up the completion processing of the auxiliary command in one block, and it is still possible to execute the next block unless the auxiliary command being executed is completed.

SUMMARY OF THE INVENTION The present invention has been made to solve the first problem. For an auxiliary command that does not need to wait for the completion of the auxiliary command, a numerical value for executing the next step without waiting for the completion of the auxiliary command. It is an object of the present invention to obtain a numerically controlled machine tool capable of correctly executing an auxiliary command in a control machine tool.

[Means for Solving the Problems]

According to the present invention, when an auxiliary command is issued from a machining program, the commanded auxiliary command is output to a programmable controller unit, and the programmable controller unit controls the machine tool in accordance with the content of the auxiliary command. In the numerically controlled machine tool to be controlled, the auxiliary command is transmitted to the next command without waiting for completion of the auxiliary command, which is required to wait for completion of the execution of the auxiliary command and execute the next command block without waiting for completion of the auxiliary command. A completion waiting unnecessary auxiliary command designating means for discriminating and specifying the completion waiting unnecessary auxiliary command which does not interfere with execution of the command block, and writing the auxiliary command to be executed at the time of executing the auxiliary command into a storage means. When the execution of the auxiliary command is completed, the information indicating that the written auxiliary command is completed is written into the storage unit. And assist instruction registration means, when the auxiliary command from machining program is commanded, the by checking the contents stored in the storage means, the auxiliary commands that assist command is commanded in the block before the command block Auxiliary command execution determination means for determining whether or not is being executed, and if it is being executed, waits for execution of the instructed auxiliary command, and if not, executing the auxiliary command. The auxiliary command executed by the auxiliary command execution availability determination means is transmitted to the completion wait unnecessary auxiliary command specifying means.
It is determined whether the command is an auxiliary command requiring completion wait or an auxiliary command not requiring completion wait, and if the command is an auxiliary command requiring wait for completion, execution of the next block is not permitted, and
If it is a completion waiting unnecessary auxiliary command, it is provided with a next block execution availability determination means for permitting execution of the next block .

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, a numerically controlled machine tool according to the present invention will be described. FIG. 1 is a schematic configuration diagram of a CNC machine tool using a CNC with a built-in PC according to Embodiment 1 of the present invention. In the figure, 1
A is an NC unit, 1OA is a CNC unit, 51 is an auxiliary command designation unit that does not need to wait for completion to specify an auxiliary command that does not need to wait, 52 is an execution auxiliary command registration unit that registers an auxiliary command to be executed, and 53 is an execution auxiliary command registration An auxiliary command storage unit for storing the execution auxiliary command registered in the unit 52, an auxiliary command storage unit for execution 54 checks the auxiliary command storage unit 53 for execution when an auxiliary command is specified, and determines whether the specified auxiliary command can be executed. Is a next block execution possibility determination unit that determines whether the next block can be executed without waiting for the completion of the auxiliary command being executed.

Reference numeral 56 denotes a test mode lock designating means for designating an auxiliary command which is not executed during the test mode.
57 is a test lock storing means for storing the auxiliary command specified by the test mode lock specifying means, 58 is a check for the test lock storing means in the test mode, and execution of the auxiliary command specified by the machining program A test lock determining means 59 for determining whether or not the auxiliary command can be executed even when the auxiliary command is locked by a locking means (not shown) for locking the auxiliary command so as not to be executed; Time forced output designating means.

Reference numeral 60 denotes a forced output storage means for storing the auxiliary command specified by the test mode forced output specifying means, and 61 denotes a state in which the auxiliary command is locked by the lock means in the test mode. However, it is also a forced output determination unit that checks the forced output storage unit and determines whether the auxiliary command specified by the machining program can be executed. Also, the components having the same reference numerals as those in FIG. 10 have the same contents, and the description is omitted.

FIG. 2 is a screen display example for designating an M command according to the first embodiment of the present invention. It can be set on a screen on the NC operation panel 11. In the figure, reference numeral 161 denotes an M command value, and 163 denotes a table for specifying an M command that does not need to wait for completion (hereinafter, referred to as a “waiting for completion” section). Regarding the M command in which “*” is added to the “wait for completion” section 163,
Even if the M command is being executed, the next command can be executed without waiting for the completion of the M command. To specify "*", the cursor is moved to the "waiting for completion" section 163 of the corresponding M command, and if there is no need for waiting for completion, the numerical value "1" is keyed in. When "1" is keyed in, a mark "*" is displayed on the screen, indicating that the corresponding M command has been designated as an M command that does not require completion wait. If it is an M command that requires waiting for completion, the key-in may be “0”. When "0" is keyed in, the corresponding portion is blank on the screen.

Reference numeral 164 denotes a table for specifying an M command for locking the output of the M command in the test mode (hereinafter, a table 164).
"Test lock" section), "Test lock" section 16
Regarding the M command in which “*” is added to 4, the M command is not output even if the M command is issued in the test mode. The designation of “*” moves the cursor to the “test lock” section 164 of the corresponding M command,
If it is an M command that locks the output of the M command in the test mode, a numerical value “1” is keyed in. When "1" is keyed in, a mark "*" is displayed on the screen, indicating that the corresponding M command has been designated as the M command for locking the output of the M command in the test mode. If it is a normal M command that does not lock the output of the M command in the test mode, “0” is keyed in. When "0" is keyed in, the corresponding portion is blank on the screen.

Reference numeral 165 denotes a table for designating an M command for outputting the M command even when the auxiliary command is locked (hereinafter, referred to as a "forced output" portion). "*" Is added to the "forced output" portion 165. With respect to the set M command, the M command is output even when the auxiliary command is locked. "*"
Is designated, the cursor is moved to the “forced output” section 165 of the corresponding M command, and if the M command is to output the M command even when the auxiliary command is locked, the numerical value “1” is keyed in.
When "1" is keyed in, a mark "*" is displayed on the screen, indicating that the corresponding M command has been designated as the M command for outputting the M command even when the auxiliary command is locked. If it is a normal M command that does not output the M command when the auxiliary command is locked, “0” is keyed in. When "0" is keyed in, the corresponding portion is blank on the screen.

First, the execution operation of a machining program during machining, particularly the execution operation of an M command, will be described with reference to FIGS. That is, FIG. 3 is a table showing the state of the M command during the machining execution operation of the machining program. This table
147 indicates an M command value (hereinafter referred to as MD) being executed by the PC unit 2.
151) is stored. In this MD 151, P
When the M command is being executed by the C unit 2, the M command being executed is stored. When the M command is not being executed, a value of “−1” is stored.

FIG. 4 is a flowchart showing the output processing of the M command during the machining execution operation of the machining program. When the M command is instructed, the NC unit 1 causes the MD 15 shown in FIG.
Checking whether the value of 1 is "-1" or not, the PC unit 2
Then, it is determined whether or not the M command is being executed (step 1201). If the M command is being executed by the PC unit 2, the PC unit 2 cannot execute the next M command, so that the output of the M command is not completed and the process ends (step 1209). In this case, since the M command has not been processed, the process does not proceed to the execution of the next command, and the output process of the M command shown in FIG. 4 is performed again later.

If the M command is not being executed in the PC unit 2, the designated M command value is stored in the MD 151 (step 1202). Next, the M command value is output to the PC unit 2 (step 1203), and the MF signal is turned on (step 1204). Next, it is determined whether the waiting for completion of the M command is an unnecessary M command (step 1205). This is shown in FIG.
Is to determine whether or not the command is an M command in which “*” is specified in the “waiting for completion unnecessary” section 163.

If the M command needs to wait for the completion of the M command,
Execution of the next instruction is not permitted (step 1206). When this “next command execution is not permitted”, the execution of the next command is M
It shall be performed after the completion of the command. If the M command does not need to wait for completion of the M command, execution of the next command is permitted (step 1207). When the “next command execution permission” is reached, the next command is executed without waiting for the completion of the M command. Since the output of the M command to the PC unit 2 has been completed, the process ends as the output of the M command is completed (step 120).
8).

The process shown in FIG. 4 is a portion which is started when the processing of the M command is required in the program executed at regular intervals. In the figure, the output of the M command is not completed (step 1209). ), The process of FIG. 4 is performed again in the next cycle, and the output of the M command is completed (step 1208).
It is executed repeatedly until

FIG. 5 is a flowchart showing the completion processing of the M command during the machining execution operation of the machining program. In the PC section 2, when the commanded M command is completed, a completion signal (FIN) is sent to the NC section 1. In response to this, the NC unit 1 performs the following processing. First, since there is no M command being executed in the PC unit 2, the MD 15
The value of 1 is set to "-1" (step 1301). Next, the MF signal is turned off (step 1302), and the FI
The N signal is turned off (step 1303).
The command BCD output is turned off (step 1304) and the process ends.

FIG. 6 is an explanatory diagram for explaining the processing of the NC unit 1 and the PC unit 2. 201 to 203 are PCs from the NC unit 1
M command value to be output to the unit 2,
Reference numeral 17 denotes a value of the MD 151, and reference numerals 221 to 226 denote internal states of the PC unit 2. Now, when Ma is commanded (2
01), the value of MD 151 is “−1” (21)
1) The data is output to the PC unit 2 as it is, and the value of the MD 151 is changed to “a”. Here, a is a command value of M.

The PC section 2 receives this and executes Ma (221). At the time when execution of Ma is completed (222), M
The value of D151 is "-1" (213). When the next M command Mb is instructed (202), since the value of MD 151 is "-1" (213), the data is directly output to the PC unit 2 and the value of MD 151 is changed to "b". Here, b is a command value of M.

The PC section 2 receives this and executes Mb (223). When the next M command Mc is commanded (20
3) Since the value of the MD 151 remains “b” because the PC unit 2 is still executing the Mb, the data output to the PC unit 2 is stopped, and the value of the MD 151 becomes “−1”. wait.

When the execution of Mb is completed, the PC 2
The value of D151 is set to "-1" (224). As a result, the NC unit 1 outputs the M command Mc to the PC unit 2 and the MD 151
Is changed to “c”. Here, c is a command value of M. The PC section 2 receives this and executes Mc (22)
5). When the execution of Mc ends (226), MD15
The value of 1 is set to "-1" (226). In the example of FIG. 6 , it is assumed that Ma, Mb, and Mc are all M commands that need not wait for the completion of the M command.

In the above example, the conventional NC unit 1 and P
Although the case where the interface with the C unit 2 is used as is is shown, in the case of a built-in PC which has been increasing recently, N
Many of the C unit 1 and the PC unit 2 have a structure that has a common memory and can exchange data with each other.
It is no longer necessary to provide an interface between the conventional NC unit 1 and PC unit 2.

For example, the signal of MF or FIN is N
This is necessary when the C unit 1 and the PC unit 2 can only transmit and receive data in bit units. In a system having a built-in PC, the NC unit 1 and the PC unit 2 have a common memory, If you can freely exchange data with each other, MD151
The processing of the M command can be performed only by the above. That is, the M command value is set to N
When sending from the C section 1 to the PC section 2, it is only necessary to set the M command value to the MD 151. When notifying the NC section 1 of the completion from the PC section 2, simply set the MD 151 to “−1”. Is fine.

The NC unit 1 can confirm the completion of the M command by setting the MD 151 to "-1".
The MD 151 indicates that the M command has been sent from the C unit 1 to “−”.
This can be confirmed by a value other than “1”. For systems having such a built-in PC, it is possible to omit the processing in step 1203 and 1204 in FIG. 4, as shown in FIG.

In the above description, the M command that does not need to wait for the completion of the M command is set from the screen, but a distinction between waiting for the completion of the M command and not waiting may be specified in the machining program. . For example, the M command that needs to wait for the completion of the M command defines the M command value with a capital letter "M", such as M123; and the M command that does not need to wait for the completion of the M command, uses a lowercase letter, such as m123; The M command value is defined by “m”, and the determination in step 1205 of FIGS. 4 and 6 is performed so as to determine whether the designated M command is commanded by “M” or “m”. I just need.

Further, the distinction of M is not limited to the above. For the M command which needs to wait for the completion of the M command, the M command value is defined by a value of "+" as in the past, such as M123; The M command that does not need to wait for the completion of may be defined as a value of “−”, such as M-123; In addition, as a method of separating the two in the machining program, a lowercase letter is added to an M command that does not need to wait for completion of the M command, such as “M123;” and “Mw123;”, or “M123;”, “M123;” It is also possible to add a special character to the M command that does not need to wait for the completion of the M command as in M @ 123; In this way,
Instead of distinguishing specify completion waiting unnecessary assisting command in the manner shown in Figure 2, when a distinguishable specified by the presence or absence of upper / lower case or symbols such as the completion waiting unnecessary assisting command in the machining program, Tsugibu lock The execution availability determination unit 55 determines whether the completion waiting auxiliary command or the completion waiting unnecessary auxiliary command is specified by the distinction designation of the auxiliary command in the machining program. The execution operation of the machining program, particularly the execution of the M command, during machining in the first embodiment operates as described above.

Next, the operation when the machining program is tested in the test mode will be described with reference to FIGS. 1, 2 and 8. FIG. 8 is a flowchart showing the output processing of the M command. If the M command has been issued, it is determined whether or not it is in the test mode (step 1401).
This test mode is designated by a selection switch (not shown) on the NC operation panel 11.

If not in the test mode, the output processing of the M command is performed as usual (step 1403). If in the test mode, it is checked whether the designated M command is an M command for locking the output of the M command in the test mode (step 1402). This is shown in FIG.
This is to determine whether or not the command is an M command in which “*” is designated in the “test lock” section 164. If the command is an M command that locks the output of the M command in the test mode, the process ends without outputting the M command. This means that the specified M command has been ignored. The numerically controlled machine tool according to the first embodiment operates as described above when a machining program is tested in the test mode.

Next, FIGS. 1, 2 and 9 show the operation when the machining program is tested in a state where the lock means for locking the auxiliary program so as not to execute the auxiliary command is operating.
This will be described with reference to FIG. That is, FIG. 9 is a flowchart showing the output processing of the M command. When the M command is issued, it is determined whether or not the auxiliary command is locked (step 1).
501). This auxiliary command lock is specified by the NC operation panel 1
1 by using a selection switch (not shown).

If the auxiliary command is not locked, output processing of the M command is performed as usual (step 1503). If the auxiliary command is locked, it is checked whether the designated M command is an M command that outputs the M command even when the auxiliary command is locked (step 1502). This is to determine whether or not the command is an M command in which “*” is designated in the “forced output” section 165 in FIG.

M for outputting M command when auxiliary command is locked
If not, the process is terminated without outputting the M command. This means that the specified M command has been ignored. If the M command outputs the M command when the auxiliary command is locked, the M command is output even when the auxiliary command is locked (step 1503). The numerically controlled machine tool according to the first embodiment operates as described above when a machining program is tested in a state in which a lock unit that locks so as not to execute an auxiliary command is operating.

[0045]

According to the numerically controlled machine tool according to the present invention, the following effects can be obtained. That is, if the commanded auxiliary command is an auxiliary command that does not need to wait for completion, in order to reduce the processing time, as in the invention described in Japanese Patent Application Laid-Open No. 62-189506, the auxiliary command If the system is configured to execute the block (which may be a G code or an auxiliary command) next to the block in which the auxiliary command exists before the execution is completed, the following problem occurs. Occurs. That is, even if the machining program causes the block following the block in which the auxiliary command exists to be executed before the completion of the execution of the auxiliary command if the block following the block in which the auxiliary command exists is the G code. No problem. However, for example, if the auxiliary command is also present in the block next to the block in which the auxiliary command is present, if the auxiliary command of the next block is executed before the execution of the auxiliary command in the previous block is completed, the programmable controller In some cases, the sub-unit may still be executing the auxiliary command existing in the previous block.In such a case, the auxiliary command of the next block is ignored or the execution of the auxiliary command being executed is interrupted and the next block is executed. However, according to the first aspect, such an inconvenience does not occur. In order to solve this problem, it is conceivable to change the existing programmable controller. However, changing the existing programmable controller is not practical due to a significant change in configuration.

[Brief description of the drawings]

FIG. 1 shows a built-in PC according to a first embodiment of the present invention.
FIG. 1 is a schematic configuration diagram of a CNC machine tool using a CNC with a hole.

FIG. 2 is a diagram showing an example of a screen display for designating an M command according to Embodiment 1 of the present invention;

FIG. 3 is an explanatory diagram of a table showing a state of an M command according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing output processing of an M command according to Embodiment 1 of the present invention.

FIG. 5 is a flowchart showing completion processing of an M command according to Embodiment 1 of the present invention.

FIG. 6 shows an NC unit and a PC according to Embodiment 1 of the present invention.
FIG. 9 is a diagram illustrating processing of a unit .

FIG. 7 is an output of an M command according to the first embodiment of the present invention.
It is a flowchart which shows the modification of a process .

FIG. 8 is a flowchart showing an operation when a machining program is tested in a test mode according to the first embodiment of the present invention.

FIG. 9 is a flowchart showing an operation in a case where the machining program is tested in a state in which a lock unit that locks so as not to execute an auxiliary command is operating, according to the first embodiment of the present invention;

FIG. 10 shows C using a conventional CNC with a built-in PC.
It is a schematic diagram of an NC machine tool.

FIG. 11 is an explanatory diagram of an interface of an auxiliary function signal.

FIG. 12 is a time chart of an M command processing operation.

FIG. 13 is a diagram showing a flow from creation of a machining program to inspection of a workpiece.

Claims (1)

(57) [Claims] When an auxiliary command is issued from a machining program, the auxiliary command is output to a programmable controller, and the programmable controller controls a machine tool according to the content of the auxiliary command. In the numerically controlled machine tool, the auxiliary command is transmitted to the next command block without waiting for completion of the auxiliary command which needs to wait for completion of execution of the auxiliary command and execute the next command block without waiting for completion of execution of the auxiliary command. allowed to run to distinguish specified in the completion waiting unnecessary assist command no safe to complete
And waiting unnecessary assist command specifying means, said auxiliary its run when running the command writes the auxiliary command in the storage means, the written assist command the storage information indicating that a complete run the upon completion execution of assist command and executing assist command register means for writing the unit, when the auxiliary command is commanded from the machining program, by checking the contents stored in the storage means, commanded by the previous block from the block in which the assist command is commanded Auxiliary command for determining whether or not a given auxiliary command is being executed, and if so, suspending execution of the specified auxiliary command, and executing the auxiliary command if not. The execution instruction determining means and the auxiliary instruction executed by the auxiliary instruction execution determining means are designated by the completion wait unnecessary auxiliary instruction designating means.
Completion waiting main assist instruction was to determine whether any of completion waiting unnecessary assist instruction, while not permitted to execute the next block if it is waiting to complete essential auxiliary command is waiting to complete required assist command Allow execution of next block in case
A numerically controlled machine tool comprising : a next block execution availability determination unit.