JP2011096114A - Numerical control device, method of controlling machine tool, and control program of the machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably and allocate a fixed portion of processes of a processor to control processes of peripheral equipment, without fail, without increasing the complexity of software or hardware. <P>SOLUTION: A numerical control device for controlling a plurality of operations, regarding servos 3, 4 and the peripheral devices includes the processor 13; a system control cycle timer 111; a system control cycle interrupt generator 112, which generates a first interruption request to the processor 13 at a system control cycle; a servo-synchronizing cycle timer 122 which is different from the system control cycle timer 111; a servo-synchronizing cycle interrupt generator 123, which generates a second interrupt request to the processor 13 at a servo-synchronizing cycle; a timer cycle divider 123a, which divides the cycle of the second interruption request into a predetermined number of sections; and a servo-synchronizing cycle interrupt generator 123, which generates a third interruption request for controlling the peripheral equipment to the processor 13, at the start of a predetermined section. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a numerical control device that numerically controls the operation of a machine tool including a plurality of servo drive mechanisms and peripheral devices, a control method for the machine tool, and a control program for the machine tool.

  A general machine tool operates a workpiece or a tool by controlling a plurality of servo drive mechanisms. Depending on the machine tool, a splash cover door opening / closing device that covers the machine tool, a coolant device that jets and circulates cleaning liquid and coolant, a chip conveyor device that discharges chips, and a loader robot that loads and unloads workpieces It is necessary to control the operation of various peripheral devices. An NC machine tool controlled by a numerical control device (Numerical Control) composed of a computer that has been used in recent years performs automatic control of a servo drive mechanism and peripheral devices according to an NC program.

  Conventionally, in order to control the plurality of servo drive mechanisms and peripheral devices in parallel, a programmable controller is provided corresponding to each peripheral device in addition to the numerical control device. Programmable controller, mainly in cooperation with a numerical control device that controls the operation of multiple servo drive mechanisms, controls the operation of each peripheral device in accordance with each sequential program, so that the NC machine tool as a whole can be harmonized. It was possible.

  In recent years, it has become possible to process all of the operation control individually performed by the numerical control device and the plurality of programmable controllers with a single processor of the numerical control device, as the functions of the processor become higher. As described above, when the control processing conventionally executed by a plurality of processors is integrated on a single processor, in order to maintain the conventional performance, the individual control processing originally performed by another processor is not performed. Therefore, it is required to allocate a new processor occupancy ratio (distribution of processable time) so as not to be affected by the length of each control process.

  As a specific control method for that purpose, there is a method in which one processor of a numerical control device switches a large number of control processes on a real-time OS at predetermined time intervals and performs parallel processing in a time division manner. In addition, after an interrupt requesting the start of each time-sharing process occurs, an elapsed time determination process provided in the real-time OS internally counts the elapsed time and controls when a predetermined elapsed time has elapsed. There is a method of managing time so as to start execution of processing (see, for example, Patent Document 1).

  After an interrupt requesting the start of each time-sharing process occurs, when a control process with a high priority is completed, there is also a method of performing the control process by the amount instructed by the function managed by the number of instructions (for example, Patent Document 2).

JP 2002-132306 A JP-A-8-320712

  In the conventional technique described in Patent Document 1 in which the elapsed time determination process as described above manages the time for starting the execution of the control process, the elapsed time determination process itself depends on the timer interrupt of the real-time OS. In this case, it is necessary to set interrupts at a uniform period that is shorter than the servo synchronization period, which is the period for performing the servo control process that is the main control process for the numerical control device. It becomes useless. In other words, in order to prevent peripheral device control processing that has been performed by a programmable controller from being affected by the length of the servo control processing and the length of the servo synchronization cycle, the peripheral processing is shorter than the servo synchronization cycle. There is a problem that it is necessary to set a timer interrupt at a cycle that can ensure the occupation rate of the processor that is desired to be assigned to the control processing of the device, and an interrupt that only counts up the elapsed time becomes excessive.

  In the conventional technique described in Patent Document 2 in which the control processing function is managed by the number of instructions, the processing needs to be managed by the number of instructions N, and the function of managing the number of instructions N is changed in that the capacity of the processor is consumed. There is no.

  In a numerical control device, it is considered that a separate configuration has an external interrupt mechanism and obtains an interrupt at an arbitrary timing to perform control processing in order to make maximum use of the processor capacity. If you want to operate multiple machine tools with different configurations with the same numerical control device and the same hardware, if the servo synchronization cycle varies depending on the configuration difference (number of servos and communication distance with servo), numerical control device It is necessary to provide a function for setting an interrupt timing to an external interrupt mechanism. In this case, a dedicated communication line for setting the interrupt timing from the numerical controller to the external interrupt mechanism and a processing mechanism for generating a dedicated protocol for setting the interrupt timing between the numerical controller and the external interrupt mechanism are provided. Therefore, the hardware scale of the numerical control device or the software development cost increases and the cost increases.

  All of the above-described prior arts execute a real-time OS, control processing mechanism software, and hardware in order to execute not only servo control processing but also peripheral device control processing by only one processor of the numerical control device. Cause a significant increase in complexity.

  An object of the present invention is to stably and surely allocate a certain percentage of the processing of the processor, which is a calculation means for operation control, to the control processing of the peripheral device without complicating software and hardware. A numerical control device, a machine tool control method, and a machine tool control program are provided.

  In order to achieve the above object, a numerical controller according to a first aspect of the present invention includes a machine tool main body provided with a servomotor for moving a tool or a workpiece, and a plurality of peripheral devices related to predetermined peripheral equipment related to the machine tool main body. Is a numerical control device for controlling the operation of the calculation means with respect to the calculation means at a predetermined cycle in the timing of the calculation means, the first timer, and the first timer. A first interrupt generating means for generating a first interrupt according to a period; a second timer different from the first timer; and a predetermined period in the time counting of the second timer; Second interrupt generation means for generating a second interrupt for servo data transmission / reception, and the second interrupt cycle by the second interrupt generation means is divided into a plurality of predetermined sections. And a third interrupt generating means for generating a third interrupt for controlling the peripheral device to the computing means at the start of a predetermined section among the plurality of sections divided by the dividing means. It is characterized by having.

  The numerical control device according to the first aspect of the present invention includes a first timer and a first interrupt generation means. The first interrupt generation means generates a first interrupt according to the period of the operation clock of the calculation means at a predetermined period measured by the first timer. Thereby, schedule management of a plurality of program functions on the real-time OS is performed.

  The numerical control apparatus according to the first aspect of the present invention includes a second timer, a second interrupt generating means, a dividing means, and a third interrupt generating means. The second interrupt generating means generates a second interrupt for servo data transmission / reception with the servo motor at a predetermined cycle by a time measured by a second timer different from the first timer. The dividing means divides the period of the second interrupt into a plurality of predetermined sections. The third interrupt generation means generates a third interrupt for controlling peripheral devices of the machine tool at the start of a predetermined section among the plurality of divided sections.

  As a result, command data can be transmitted to the servo motor at a predetermined timing with the servo motor in the second interrupt, and the return data can be received to capture the current position of the servo motor. In addition, by setting the third interrupt at a timing at which the process of receiving the return data from the servo motor is surely completed, the control processing of the peripheral device having different properties is performed at the timing of the third interrupt. Command data to be transmitted at the time of interruption can be generated after the control processing of the peripheral device is completed.

  As a result, the first interrupt by the first timer that informs the time to the normal real-time OS can be set sufficiently large with respect to the servo synchronization period by the second timer. That is, the command data to the servo motor can be transmitted at a timing synchronized with the servo motor without making the first interrupt due to the system clock on the real-time OS fine. A control section in which no transmission / reception process of command data and reply data with the servo motor occurs can be reliably obtained in the form of a third interrupt.

  Therefore, according to the first invention of the present application, it is possible to stably and surely allocate a certain proportion of the processing of the computing means to the control processing of the peripheral device without complicating software and hardware.

  According to a second aspect of the present invention, in the first invention, the second interrupt generation unit generates the second interrupt at a cycle shorter than the cycle of the first interrupt generated by the first interrupt generation unit. It is characterized by making it.

  As a result, the command data to the servo motor can be reliably transmitted to the servo motor in the second interrupt by the second interrupt generating means without making the first interrupt by the first interrupt generating means according to the system clock on the real-time OS fine. It can be transmitted at synchronized timing.

  A numerical control device according to a third aspect of the present invention is the first or second aspect of the invention, in order to perform synchronous communication periodically between the servo motor and the arithmetic means, a servo communication bus connected to the servo motor, First communication interface means for performing input / output control with the arithmetic means, second timer setting means capable of changing the cycle and timing of the second timer, the servo communication bus, and the second timer setting means, The arithmetic means and the servo motor are synchronized with the second communication interface means for performing the input / output control of the servo motor and the servo timer setting means capable of changing the cycle and timing of the servo timer for generating the operation timing of the servo motor. And setting the cycle and timing for the second timer setting means, via the servo communication bus, The period and timing for synchronizing with serial arithmetic means and said second interrupt generating means and the third interrupt generating means and further comprising a timer setting means for setting through the servo communication bus.

  Thereby, the synchronization of the second interrupt by the second interrupt generating means and the third interrupt by the third interrupt generating means can be set reliably through the servo communication bus.

  According to a fourth aspect of the present invention, in the numerical control device according to any one of the first to third aspects, the third interrupt generation means avoids a congested section of the servo communication bus from the plurality of sections, and On the other hand, the third interrupt is generated.

  As a result, a certain proportion of the processing of the computing means can be stably distributed to the control processing of the peripheral devices without increasing the burden on the computing means.

  In order to achieve the above object, a machine tool control method according to a fifth aspect of the present invention relates to a machine tool body provided with a servo motor for moving a tool or a workpiece, and a predetermined peripheral device related to the machine tool body. A machine tool control method for controlling a plurality of operations by multitasking, wherein a first interrupt corresponding to a cycle of an operation clock of an arithmetic means provided in the machine tool is generated at a predetermined first cycle. A procedure, a procedure for generating a second interrupt for transmitting / receiving servo data with the servo motor at a predetermined second cycle different from the first cycle, and a cycle of the second interrupt are divided into a plurality of predetermined sections. And a procedure for causing the arithmetic means to generate a third interrupt for controlling the peripheral device at the start of a predetermined section of the plurality of divided sections. And features.

  In the machine tool control method according to the fifth aspect of the present invention, the first interrupt is generated in the first cycle according to the cycle of the operation clock of the computing means. Thereby, schedule management of a plurality of program functions on the real-time OS is performed. A second interrupt for transmitting / receiving servo data with the servo motor is generated at a second period different from the first period. In addition, the second interrupt cycle is divided into a plurality of predetermined sections, and a third interrupt for controlling peripheral devices of the machine tool is generated at the start of the predetermined section among the divided sections.

  As a result, command data can be transmitted to the servo motor at a predetermined timing with the servo motor in the second interrupt, and the return data can be received to capture the current position of the servo motor. In addition, by setting the third interrupt at a timing at which the process of receiving the return data from the servo motor is surely completed, the control processing of the peripheral device having different properties is performed at the timing of the third interrupt. After completing the control process, command data to be transmitted at the next second interrupt can be created.

  As a result, the first period of the first interrupt for informing the time to the normal real-time OS can be set sufficiently larger than the second period for servo motor synchronization. That is, the command data to the servo motor can be transmitted at a timing synchronized with the servo motor without reducing the first cycle by the system clock on the real-time OS. A control section in which no transmission / reception process of command data and reply data with the servo motor occurs can be reliably obtained in the form of a third interrupt.

  Therefore, according to the fifth aspect of the present invention, it is possible to stably and surely distribute a certain ratio of the processing of the arithmetic means to the control processing of the peripheral device without complicating software and hardware.

  In order to achieve the above object, a machine tool control program according to a sixth aspect of the present invention relates to a machine tool main body provided with a servo motor for moving a tool or a work, and a predetermined peripheral device related to the machine tool main body. , A machine tool control program for controlling a plurality of operations by multitasking, wherein a computer has a first program corresponding to a cycle of an operation clock of an arithmetic means provided in the machine tool at a predetermined first cycle. A procedure for generating one interrupt, a procedure for generating a second interrupt for servo data transmission / reception with the servo motor at a predetermined second cycle different from the first cycle, and a predetermined plurality of cycles for the second interrupt. A third division for controlling the peripheral device to the computing means at the start of a predetermined section among the plurality of divided sections. Characterized in that to execute the steps of generating only.

  The computer that executes the machine tool control program of the sixth invention of the present application generates a first interrupt in the first period according to the period of the operation clock of the computing means. Thereby, schedule management of a plurality of program functions on the real-time OS is performed. A second interrupt for transmitting / receiving servo data with the servo motor is generated at a second period different from the first period. In addition, the second interrupt cycle is divided into a plurality of predetermined sections, and a third interrupt for controlling peripheral devices of the machine tool is generated at the start of the predetermined section among the divided sections.

  As a result, command data can be transmitted to the servo motor at a predetermined timing with the servo motor in the second interrupt, and the return data can be received to capture the current position of the servo motor. In addition, by setting the third interrupt at a timing at which the process of receiving the return data from the servo motor is surely completed, the control processing of the peripheral device having different properties is performed at the timing of the third interrupt. After the control process is completed, command data to be sent to the servo motor in the next second interrupt can be created.

As a result, the first period of the first interrupt for informing the time to the normal real-time OS can be set sufficiently larger than the second period for servo motor synchronization. That is, the command data to the servo motor can be transmitted at a timing synchronized with the servo motor without reducing the first cycle by the system clock on the real-time OS. A control section in which no transmission / reception process of command data and reply data with the servo motor occurs can be reliably obtained in the form of a third interrupt.
Therefore, according to the sixth aspect of the present invention, it is possible to stably and surely allocate a certain proportion of the processing of the arithmetic means to the control processing of the peripheral device without complicating software and hardware.

  According to the present invention, it is possible to stably and surely allocate a certain proportion of the processing of the calculation means to the control processing of the peripheral device without complicating software and hardware.

1 is a functional block diagram schematically showing a system configuration of a numerical control device and a servo according to an embodiment of the present invention. It is an example of the time chart which shows the relationship between the timing of each interruption request | requirement, and execution of each process. It is an example of the time chart which shows the relationship between a servo synchronous period and a system control period. It is a flowchart showing the control procedure which the processor of a numerical controller performs. It is a figure showing the network form between a processor and each apparatus. It is a figure showing the relationship of the propagation delay time between communication interfaces, and the offset time between each period. It is a flowchart showing the detailed procedure of the synchronous process of step S100 in FIG. It is a figure showing the modification of the network form between a processor and each apparatus.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a functional block diagram schematically showing the system configuration of the numerical controller and the servo. The numerical control device 1 controls a plurality of operations in the entire machine tool main body (not shown in particular) by multitasking (hereinafter referred to as time division control as appropriate).

  As shown in FIG. 1, the numerical controller 1 is connected to a plurality of servos 3 and 4 via a servo communication bus 2 so as to be able to transmit and receive information. In the drawing, for convenience of illustration, only two servos 3 and 4 are connected to the servo communication bus 2, and in the following description, an example in which only two servos are connected will be described. It is good also as a structure to connect. Although the numerical control apparatus 1 performs operation control on a plurality of peripheral devices other than the servos 3 and 4, illustration of these peripheral devices is omitted.

  The numerical controller 1 includes a system control interrupt circuit 11, a servo synchronization interrupt circuit 12, and a processor 13. The numerical control apparatus 1 includes a first communication interface 14 as a first communication interface means for the processor 13 to be communicably connected to the servo communication bus 2, and the servo synchronization interrupt circuit 12 in the same servo communication bus 2. It has the 2nd communication interface 15 as a 2nd communication interface means for connecting so that communication is possible. In the figure, the circuits 11 and 12 and the processor 13 are distinguished from each other in terms of hardware, but the functional blocks provided in each are distinguished from each other by internal processing functions. In particular, all the functional blocks inside the processor 13 are shown as software blocks distinguished by software processing.

  The system control interrupt circuit 11 outputs a first interrupt request (see FIGS. 2 and 3 to be described later) that triggers switching of a plurality of processes executed by the processor 13 on the real-time OS in a time division manner. The system control interrupt circuit 11 includes a system control cycle timer 111 and a system control cycle interrupt generator 112. The system control period timer 111 as the first timer described in each claim counts the reference clock of the processor 13 and notifies it every time a system control period (see FIG. 3 described later) set to a predetermined time length elapses. . The system control cycle interrupt generator 112 serving as the first interrupt generation means described in each claim, when the system control cycle timer 111 notifies of the passage of time, the first interrupt request which is the first interrupt described in each claim. A signal is generated and output to the processor 13.

  The servo synchronization interrupt circuit 12 is a second trigger for starting the control processing of the servos 3 and 4 for each servo synchronization period of a predetermined time length as a reference for the processor 13 to perform synchronous control with the servos 3 and 4. An interrupt request (see FIG. 2 described later) is output. The servo synchronization interrupt circuit 12 outputs two third interrupt requests (see FIG. 2 to be described later) that trigger the start and end of the peripheral device control processing at the same appropriate timing during each servo synchronization period. To do.

  The servo synchronization interrupt circuit 12 includes a servo synchronization period setter 121, a servo synchronization period timer 122, and a servo synchronization period interrupt generator 123. The servo synchronization cycle setting unit 121 as the second timer setting means is configured to send a servo synchronization cycle to the servo synchronization cycle timer 122 in accordance with a setting command received from the processor 13 via the two communication interfaces 14 and 15 and the servo communication bus 2. And the phase, that is, the start timing of the servo synchronization period is set. The servo synchronization period timer 122 as the second timer described in each claim counts the reference clock of the servo synchronization interrupt circuit 12, and the start period of the set servo synchronization period (see FIGS. 2 and 3 to be described later) elapses. A time lapse signal is output each time. Note that the reference clock of the servo synchronization interrupt circuit 12 may be the same as the reference clock of the processor 13.

  The servo synchronization period interrupt generator 123 serving as the second interrupt generation means and the third interrupt generation means according to each claim receives the time lapse signal from the servo synchronization period timer 122 and outputs the second interrupt according to each claim. The second interrupt request signal is generated and output to the processor 13. The servo synchronization period interrupt generator 123 includes a timer period divider 123a as a dividing means described in each claim. The timer period divider 123a divides the servo synchronization period and equally divides it into a plurality of sections. The servo synchronization period interrupt generator 123 generates the two third interrupt request signals as the third interrupt according to each claim at the start of each of the two equally divided sections at a predetermined timing, 13 (see FIG. 2 described later).

  The processor 13 executes the control program or the like to control the analysis of the NC program and the operation of the entire machine tool (not shown) including the servos 3 and 4 and peripheral devices. It is a calculation means. The processor 13 includes a real-time OS scheduler 131, a normal processing unit 132, an interrupt scheduler 133, a peripheral device processing unit 134, a servo command generation unit 135, a servo transmission / reception processing unit 136, and a synchronization cycle setting command unit 137 as the software blocks described above. Have.

  Each time the real-time OS scheduler 131 receives the first interrupt request signal from the system control cycle interrupt generator 112 of the system control interrupt circuit 11, the processor 13 is to execute a plurality of processes to be processed in parallel on the real-time OS at that time. The processes to be executed after that are selected and designated, and individual processes are started and interrupted. The normal processing unit 132 executes the process selected and specified by the real-time OS scheduler 131 as a normal process (see FIG. 2 described later) until the real-time OS scheduler 131 is activated and interrupted.

  The interrupt scheduler 133 gives priority to processing on the real-time OS over normal processing every time the second interrupt request or third interrupt request signal is input from the servo synchronization period interrupt generator 123 of the servo synchronization interrupt circuit 12. One of servo transmission / reception processing, peripheral device processing, and servo command generation processing, which will be described later, which is set to a high degree, is selected and specified in an appropriate order to start and interrupt each processing.

  The peripheral device processing unit 134 executes the peripheral device processing in a time-sharing manner until the interrupt scheduler 133 starts the peripheral device processing and interrupts it. The servo command generation unit 135 starts executing the servo command generation processing at the timing when the interrupt scheduler 133 selects and activates the servo command generation processing. The servo transmission / reception processing unit 136 starts executing the servo command transmission process for transmitting command data in the servo transmission / reception process at the timing when the interrupt scheduler 133 selects and activates the servo transmission / reception process. At this time, the servo transmission / reception processing 136 transmits command data to the servo controllers 34 of the first servo 3 and the second servo 4 via the communication interfaces 14 and 31 and the servo communication bus 2. Then, immediately after receiving the command data, the first servo 3 and the second servo 4 transmit the reply data to the servo transmission / reception processing 136 via the communication interfaces 14 and 31 and the servo communication bus 2. The servo transmission / reception processing unit 136 executes a servo response reception process for receiving the return data in the servo transmission / reception process at the timing when the return data is received. As will be described in detail later, the transmission / reception processing of the command data by the servo transmission / reception processing unit 136 and the reception processing of the return data are repeated for all servos until all the command data can be transmitted and the return data can be received. Is also divided and mixed.

  The synchronization cycle setting command unit 137 serving as a timer setting means is connected to the servo synchronization cycle setting unit 121 and servo control (described later) of the servos 3 and 4 via the communication interfaces 14, 15 and 31 and the servo communication bus 2. A setting command for causing the timers 122 and 33 to set the servo synchronization cycle and start timing set to a predetermined time length and the servo control cycle and start timing of the same time length is transmitted to the cycle setter 32. The servo synchronization period setting unit 121 and a servo control period setting unit 32, which will be described later, can receive a setting command transmitted from a mechanism constituted by the same hardware or the synchronization cycle setting command unit 137, in other words. The synchronization cycle must be a similar mechanism that can determine the common communication protocol that is instructed to change the timer period and start timing of the receiving side, and that can change its timer period and start timing. The setting command unit 137 can reduce the scale of processing, which is very desirable.

  Of the circuits 11 and 12 and the processor 13 included in the numerical controller 1 having the above-described configuration, the system control interrupt circuit 11 and the servo synchronization interrupt circuit 12 each have a high execution speed and do not require a dedicated program. It can be configured by a hardware circuit having a relatively simple structure. Only the processor 13 functions as a programmable controller that operates based on a dedicated program.

  In this example, the servo communication bus 2 has a configuration conforming to the Ethernet (registered trademark) standard. The servo communication bus 2 may be configured to use other serial communication.

  The first communication interface 14 functions as an interrupt circuit that outputs signals of a servo command transmission interrupt request and a servo response reception interrupt request, which will be described later, at a timing at which data in packet units is transmitted to and received from the processor 13.

  Each of the servos 3 and 4 is a servo motor according to claims for moving a tool or a workpiece (not shown), and includes a servo communication interface 31, a servo control cycle setter 32, a servo control cycle timer 33, a servo And a controller 34. The functional blocks included in the servos 3 and 4 are distinguished by internal processing functions, and the internal functional blocks of the second servo 4 are omitted.

  The servo control cycle setting unit 32 as a servo timer setting means has a servo control cycle having the same length as the servo synchronization cycle according to a setting command received from the processor 13 via the two communication interfaces 14 and 31 and the servo communication bus 2. The servo control cycle phase, that is, the start timing of the servo control cycle is set in the servo control cycle timer 33. The servo control cycle timer 33 as a servo timer starts a time measurement operation of the servo control cycle at the set start timing, and outputs a time lapse signal every time the start of the servo control cycle of the set time length elapses. The servo controller 34 controls the drive control of the servos 3 and 4 based on the contents of the command data received from the processor 13 via the two communication interfaces 14 and 31 and the servo communication bus 2 from the servo control cycle timer 33. Execution starts when a signal is input. When the command data is received, the actual positions and current values of the servos 3 and 4 are measured, and return data as a servo control response is returned to the processor 13. The command data of the servo control command and the response data of the servo control response correspond to the servo data described in each claim.

  The relationship between each interrupt request and each process in the processor 13 will be specifically described. FIG. 2 shows an example of a time chart showing the relationship between the timing of each interrupt request and the execution of each process in the present embodiment. The processor 13 inputs each interrupt request signal from which interrupt circuit 11 or 12 so as to be able to distinguish which content is the interrupt request.

  In the example shown in FIG. 2, the time interval of the time lapse signal repeatedly output by the servo synchronization period timer 122 of the servo synchronization interrupt circuit 12, that is, the servo synchronization period is set to 200 μsec. In this example, the timer period divider 123a of the servo synchronization period interrupt generator 123 divides the servo synchronization period three times and equally divides it into eight sections. The servo synchronization period interrupt generator 123 outputs a second interrupt request at the beginning of the first equally divided section of these eight, that is, at the beginning of the entire servo synchronization period. In this example, the servo synchronization period interrupt generator 123 outputs a third interrupt request at the start of each of the sixth and seventh equally divided sections of the eight.

  The processor 13 basically executes normal processing at normal time, and when each interrupt request is input, the processor 13 operates the interrupt scheduler 133 with the highest priority, and the interrupt scheduler 133 performs the above-described servo command transmission processing, servo A so-called hardware interrupt is performed in which any one of response reception processing, peripheral device processing, and servo command generation processing is selected and executed in an appropriate order.

  Specifically, the processor 13 starts executing the servo command transmission process when the second interrupt request is input from the servo synchronization period interrupt generator 123 at the beginning of the entire servo synchronization period. The servo command transmission process is a process of transmitting a corresponding servo control command to be described later to each of the plurality of servos 3 and 4 included in the machine tool. The processor 13 executes a servo response reception process when receiving a servo control response from the servos 3 and 4 that have finished executing the servo control command.

  In the servo command transmission process, servo control commands are transmitted to the plurality of servos 3 and 4 in order. The execution time from receiving the servo control command of each servo 3, 4 to returning the servo control response is relatively short. When the number of installed servos 3 and 4 is large, the processor 13 receives the first servo control response at the processor 13 and completes the servo before completely transmitting all the servo control commands by the servo command transmission process. Response reception processing is often started.

  As described above, in this example, since the servo communication bus 2 has a configuration conforming to Ethernet (registered trademark), the processor 13 and the servos 3 and 4 store the servo control command and servo control response data in a capacity. Send and receive in small packets. While transmitting and receiving packets between the communication interfaces 14 and 31, the processor 13 executes normal processing in a time division manner. When the packet transmission / reception is completed, the processor 13 returns to either the servo command transmission process or the servo response reception process by inputting an interrupt request (not shown) from the first communication interface 14. The processor 13 divides and mixes the normal process, the servo command transmission process, and the servo response reception process repeatedly with the input of the second interrupt request as a trigger.

  The processor 13 switches to the peripheral device processing when the first third interrupt request is input from the servo synchronization cycle interrupt generator 123 at the beginning of the sixth equally divided section after the servo response reception processing is completed. Start execution. Peripheral device processing is processing for performing operation control on various peripheral devices included in the machine tool. When the processor 13 includes a plurality of peripheral device processes to be controlled, the processor 13 has a peripheral device scheduler, and executes the processing by sequentially starting the processing every time the first third interrupt is received. However, the details are omitted here.

  When the processor 13 inputs the third interrupt request for the second time from the servo synchronization period interrupt generator 123 at the beginning of the seventh equally divided section, the processor 13 interrupts the peripheral processing that has been continuously executed until then. Then, switching to servo command generation processing is started. The servo command generation process is a process of generating command data that is a servo control command to be transmitted to each of the servos 3 and 4 in the servo command transmission process in the next servo synchronization cycle. In this example, the processor 13 refers to the return data that is the servo control response of each servo 3 and 4 received in the servo response reception process of the same servo synchronization period, and the operation of each servo 3 and 4 in the next servo synchronization period. By generating command data which is each servo control command such as a target value, so-called semi-closed loop control is performed on each servo 3 and 4. When generation of all servo control commands corresponding to the servos 3 and 4 is completed, the processor 13 switches to normal processing and resumes execution.

  As described above, the interrupt scheduler 133 of the processor 13 selects and designates five processes in the same appropriate order in each servo synchronization period, and executes them in a time-sharing manner by the corresponding processing units or generation units. Let The above-described setting of the servo synchronization period, the number of divided sections, and the timing of each interrupt request is an example, depending on the configuration and operating environment of the machine tool, such as the number of servos 3 and 4 and the installation mode of peripheral devices. Each setting may be changed as appropriate.

  When the processor 13 receives the first interrupt request from the system control cycle interrupt generator 112, the processor 13 selects the normal processing that the real-time OS scheduler 131 selects and designates as the normal processing to be executed next on the real-time OS. Let it run. Specific processing contents of the normal processing include, for example, creation of operation screen display data (not shown), input detection at the operation unit, counting up of usage time of consumables, reading and analysis of NC program instructions, etc. is there. These normal processes obtain sufficient functions even if they are switched in a period relatively longer than the servo synchronization period and executed in a time-sharing manner. For example, as shown in FIG. 3, the servo synchronization cycle needs to be set to a short cycle of about 200 μsec, whereas the normal processing can be set to a relatively long system control cycle of the order of several milliseconds. The time chart of FIG. 2 shows the range portion II in FIG. 3 in an enlarged manner.

  By following the above process, the processor 13 can execute a plurality of processes on the real-time OS in appropriate synchronization with the system control period, and can appropriately control a plurality of servos 3 and 4 and peripheral devices in the servo synchronization period. Can be executed synchronously. The processor 13 itself responds to timings when various interrupt requests are input from an external hardware circuit, without measuring each cycle, with respect to system control cycles and servo synchronization cycles having greatly different time lengths. It is only necessary to execute various processes in a time-sharing manner. The processor 13 itself does not need to perform complicated timing processing and the like in order to perform periodic processing based on a plurality of cycles, so that overhead (unnecessary processing time) on the real-time OS can be significantly reduced. The processing power of the processor 13 can be greatly reduced. In performing the operation control of the entire machine tool including a large number of servos 3 and 4 and peripheral devices, the unification of the programmable controller can be functionally realized.

  Next, a specific control procedure of the synchronization cycle setting command unit 137 for performing the synchronization control according to the present embodiment described above will be described with reference to FIG. The numerical controller 1 starts this flow when the power is turned on or when a user performs a predetermined operation.

  In step S5, the processor 13 of the numerical controller 1 determines the number of servos 3, 4 connected to the servo communication bus 2 by broadcast communication via the servo communication bus 2 and the communication interfaces 14, 15, 31. Check their types, connection routes, etc. In the example of this embodiment, the processor 13 detects one servo synchronization interrupt circuit 12 and a plurality of servos 3 and 4 as shown in FIG.

  Moving to step S10, the processor 13 of the numerical controller 1 calculates a servo synchronization period according to the type and number of servos 3 and 4 detected in step S5. Specifically, first, the processor 13 generates all the time required for transmission / reception processing based on the total amount of data transmitted / received in synchronous communication with the servos 3 and 4 and the servo control commands to be transmitted to the servos 3 and 4. Calculate the required time. In the example of the present embodiment, the time required to execute through the servo command transmission process and the servo response reception process in FIG. 2 and the time required to execute the servo command generation process are calculated.

  The processor 13 of the numerical control device 1 calculates the servo synchronization period in consideration of the necessary time for sufficiently executing the normal processing and the peripheral device processing together with the necessary time. Further, the servo synchronization period may be changed according to the performance of whether each servo 3, 4 can respond to the servo synchronization period.

  The numerical control device 1 according to the present embodiment has versatility that can correspond to various machine tool specifications by performing the above calculation and setting. The numerical control apparatus 1 may set and store the servo synchronization period in a fixed manner in advance corresponding to the specifications of the machine tool. In that case, the procedure of step S10 can be omitted.

  Proceeding to step S15, the processor 13 of the numerical controller 1 sets the servo synchronization period calculated in step S10 in the servo synchronization period setting unit 121 of the servo synchronization interrupt circuit 12, and performs servo control of the servos 3 and 4. The servo synchronization period calculated in step S10 is set as the servo control period in the period setter 32. Specifically, the synchronization cycle setting command unit 137 of the processor 13 transmits a setting command including the servo synchronization cycle calculated in step S10 to the servo synchronization cycle setting unit 121, and similarly includes the servo control cycle calculated in step S10. A setting command is transmitted to each servo control cycle setting unit 32. Each cycle setter sets a clocking period for each timer 121, 32 corresponding thereto, and starts the clocking operation of each timer 121, 35.

  In step S20, the processor 13 of the numerical controller 1 transmits and receives data between the first communication interface 14 and the communication interfaces 15 and 31 of the servo synchronization interrupt circuit 12 and the servos 3 and 4, respectively. Measure and calculate the propagation delay time.

  Hereinafter, a specific method for measuring and calculating the propagation delay time in the example of the present embodiment will be described in detail. As shown in FIG. 5, in the example of this embodiment, the processor 13 has a network configuration in which data is individually transmitted to and received from the servo synchronization interrupt circuit 12 and the two servos 3 and 4. In this case, assuming that the propagation delay times of the data transmission and reception are the same, by sending the Sync / Delay Req packets compliant with IEEE 1588 to each other between the communication interfaces 14, 15, and 31, one-way or one-way Propagation delay time can be measured and calculated.

  As shown in FIG. 5, for example, the time when the Sync packet is transmitted from the processor 13 side is T0, and the time when the Sync packet is received on the servo synchronization interrupt circuit 12 side is T1, and a response corresponding to this Sync packet is returned. The time when the Req packet is transmitted from the servo synchronization interrupt circuit 12 side is T1 ′, and the time when the processor 13 receives the Delay Req packet is T0 ′.

  The times T1 and T1 ′ detected on the servo synchronization interrupt circuit 12 side are the time measured by the servo synchronization period timer 122 that repeatedly measures the servo synchronization period of 0 to 200 μsec in this example. The times T0 and T0 ′ detected on the processor 13 side are the remainders when the system timer generated by counting the reference clock of the processor 13 after the power is turned on is divided by the servo synchronization cycle time length of 200 μsec. Time T0 and T0 ′ are also timed times that repeat 0 to 200 μsec.

  In the above case, the relationship between the times T0, T0 ′, T1, and T1 ′ is as shown in FIG. When the system control cycle timer 111 and the servo synchronization cycle timer 122 start timing independently of each other, as shown in the figure, there is a deviation in the zero base point of each timing, that is, the phase. In this example, the deviation of the zero base point of the servo synchronization period timer 122 with respect to the zero base point of the system control period timer 111, that is, the phase deviation between the two timers is defined as the first offset time To1, and the servo synchronization cycle with the processor 13 is used. Assuming that the propagation delay time of data with the interrupt circuit 12 is the first propagation delay time Td1, the following equation is established from the relationship shown in the figure.

Td1 = (T1 + To1) −T0
Td1 = T0 ′ − (T1 ′ + To1)
The first propagation delay time Td1 is
Td1 = (T1-T1'-T0 + T0 ') / 2
It becomes.

From the relationship shown in the figure, the following equation is also established.
T0 + Td1 = To1 + T1
The first offset time To1 is
To1 = T0−T1 + Td1
However, if the result is To1> 200, To1 is To1-200, and if the result is To1 <0, To1 is To1 + 200.

  In the configuration of the numerical control device 1 shown in FIG. 1, when the same hardware is used as the reference clock for the system control cycle timer 111 and the servo synchronization cycle timer 122, To1 may be 0. In case, it can be omitted.

  With respect to the other servos, the data transmission / reception propagation delay time and the phase difference between the timers can be measured and calculated by the same method, and their relationship is as shown in FIG. 6 (a) and 6 (b) are synchronized on the time axis in the right direction in the figure.

  In FIG. 6B, the second offset time To2 indicates the phase difference between the system control cycle timer 111 and the servo control cycle timer 33 of the first servo 3, and the second propagation delay time Td2 The propagation delay time of data transmission / reception with the first servo 3 is shown. The third offset time To3 indicates the phase difference between the system control cycle timer 111 and the servo control cycle timer 33 of the second servo 4, and the third propagation delay time Td3 is between the processor 13 and the second servo 4. The propagation delay time of data transmission / reception is shown.

  In the present embodiment, correction is performed to match the phase difference of each servo control cycle timer 33 at an appropriate timing so that the control operations of the servos 3 and 4 can be started simultaneously. Specifically, first, the zero base point of a new phase is determined based on the longest propagation delay time to the servo, which is the second propagation delay time Td2 in the illustrated example. As shown in the figure, the servo simultaneous base point TSs obtained by adding the second propagation delay time Td2 and the margin time Tm from the zero base point of the phase of the servo synchronization period timer 122 is set as the zero base point of the new phase.

  The margin time Tm is sufficiently longer than the time required for the processor 13 to transmit servo control commands to all the servos 3 and 4 and the time required to completely end the servo command transmission processing in FIG. Set to time. When the processor 13 starts the servo command transmission process from the time Ts1, which is the zero base point of the servo synchronization cycle timer 122, all the servos 3, 4 receive the servo control command until the time of the servo simultaneous base point TSs is reached. Can be completed. All servos 3 and 4 can start the servo control operation for the servo control command obtained immediately before at the time of the servo simultaneous base point TSs.

In the phase of the servo control cycle timer 33 of the first servo 3, the phase correction value R2 necessary for moving the initial 0 base point to the servo simultaneous base point TSs is:
R2 = To1 + Td2 + Tm-To2
It becomes.

Similarly, the phase correction value R3 necessary for moving the initial 0 base point to the servo simultaneous base point TSs in the phase of the servo control cycle timer 33 of the second servo 4 is:
R3 = To1 + Td2 + Tm-To3
It becomes.

  Depending on the specifications of the communication interfaces 14, 15, 31 and the servo communication bus 2, the propagation delay times described above become too long, which affects the interrupt schedule of the peripheral device processing shown in FIG. In FIG. 2, the case where the time from the start of the servo command transmission process to the end of the servo response reception process exceeds 5/8 of the servo synchronization period corresponds to the above. If such a problem occurs, it may be reset so as to further increase the length of the servo synchronization period in step S10.

  Returning to FIG. 4, in the next step S <b> 25, the processor 13 of the numerical controller 1 transmits the phase correction value determined as described above to the servo control cycle setting unit 32 of each corresponding servo, and each servo control. The zero base point of the phase of the period is made to coincide with the same servo simultaneous base point TSs.

  In step S30, the processor 13 of the numerical controller 1 transmits communication establishment to the servo synchronization interrupt circuit 12 and the servos 3 and 4 connected to the servo communication bus 2 to start synchronization control. The servo synchronization period interrupt generator 123 of the servo synchronization interrupt circuit 12 outputs a second interrupt request to the processor 13 when the time of the servo synchronization period timer 122 reaches the zero point of the servo synchronization period, and the sixth and seventh A third interrupt request is output to the processor 13 at the beginning of each of the first equally divided sections (see FIG. 2 above). Servo control operation for the servo control command obtained immediately before by all the servo controllers 34 at the servo simultaneous base point TSs obtained by adding the second propagation delay time Td2 and the margin time Tm from the zero base point of the servo synchronization period. Can start.

  After completing the preparation for setting all devices on the servo communication bus 2 to perform the synchronous control by the above procedure, the processor 13 of the numerical controller 1 continues to control the servo in the next step S100. Perform synchronous processing.

  FIG. 7 shows the detailed procedure of the synchronization process executed in step S100 in FIG. As shown in FIG. 3, the synchronization processing is performed in a time-sharing manner in synchronization with the system control cycle as shown in FIG. 3, and the servo command transmission processing and servo response reception are synchronized with the servo synchronization cycle as shown in FIG. Processing, peripheral device processing, and servo command generation processing are performed in a time-sharing manner in parallel. A procedure path indicated by a broken line in the figure corresponds to a call for a control procedure by various interrupt requests.

  In this synchronization process, the processor 13 of the numerical control apparatus 1 basically executes the normal process of step S105 as described above, and inputs the first interrupt request from the system control interrupt circuit 11. In this case, the process proceeds to step S110. When receiving the second interrupt request or the third interrupt request from the servo synchronization interrupt circuit 12, the processor 13 proceeds to step S120. Even when a servo command transmission interrupt request or a servo response reception interrupt request, which will be described later, is input from the first communication interface 14, the processor 13 moves to a control procedure corresponding to the situation at that time.

  When the process proceeds to step S110 due to the input of the first interrupt request, the processor 13 of the numerical controller 1 switches the processing content of the normal process based on the selection designation of the real-time OS scheduler 131.

  At this time, if the processes of S120 to 185 are not being executed, the process returns to S105 and switches to the normal process selected and designated in S110. When the processing of S120 to 185 is being executed, S120 to 185 are continued. After the processing of S120 to 185 is completed / interrupted, the processing returns to S105 and switches to the normal processing selected and specified in S110.

  When the process proceeds to step S120 due to the input of the second interrupt request or the third interrupt request, the processor 13 of the numerical controller 1 determines whether or not the input interrupt request is the second interrupt request. If the input interrupt request is the second interrupt request (Yes in step S120), it is considered that a new servo synchronization period has started, and the process proceeds to the next step S125.

  In step S125, the processor 13 of the numerical controller 1 resets the value of the count variable C for counting the number of times the third interrupt request is input in the same servo synchronization period to 0.

  Proceeding to step S130, the processor 13 of the numerical controller 1 determines whether or not the servo command generation processing has been completed at this point. If the servo command generation process has not been completely completed at this time (No in step S130), it is considered that good synchronization control cannot be performed with the setting in the current servo synchronization period, and the process proceeds to step S135. In step S135, the processor 13 of the numerical controller 1 performs error processing such as displaying an error on a display unit (not shown) or resetting the servo synchronization period in step S10, and ends this flow. If the servo command generation process is completely completed at this time (Yes in step S130), the process proceeds to the next step S140, and the servo command transmission process is started.

  In step S140, the processor 13 of the numerical controller 1 transmits a servo control command to the target servos 3 and 4 via the first communication interface 14 and the servo communication bus 2. As described above, in the example of the present embodiment, the servo communication bus 2 has a configuration conforming to the Ethernet (registered trademark) standard. Therefore, the processor 13 divides the servo control command data into small packet units. Then send. In step S140, the first communication interface 14 starts transmitting only one packet, and proceeds to the next step S145.

  In step S145, the processor 13 of the numerical controller 1 determines whether or not transmission of all packets of all servo control commands for the servos 3 and 4 has been completed. If there are remaining servo control command packets to be transmitted (No in step S145), the process returns to step S105 until the previous packet transmission in step S140 is completed, and the normal process is resumed. When the packet transmission in step S140 is completed, the first communication interface 14 outputs a servo command transmission interrupt request (not shown) to the processor 13, and the processor 13 that has detected this returns to step S140 and returns to the rest. Send the packet.

  When transmission of all packets of all servo control commands for the servos 3 and 4 has been completed (Yes in step S145), the processor 13 of the numerical controller 1 returns to step S105 and resumes execution of normal processing. When the first communication interface 14 receives a servo control response from each servo, it outputs a servo response reception interrupt request (not shown) to the processor 13, and the processor 13 that has detected this moves to the next step S150, Starts servo response reception processing.

  Since the packet to be transmitted remains in the determination of step S145, the determination does not satisfy the determination, and the first communication interface 14 is in a state where the procedure of step S105 is being executed, that is, in the middle of the servo command transmission process. A control response may be received. Even in this case, the processor 13 that has detected the servo response reception interrupt request from the first communication interface 14 proceeds to step S150 and starts the servo response reception process.

  In step S <b> 150, the processor 13 of the numerical controller 1 receives a servo control response via the first communication interface 14. The processor 13 also receives this servo control response in units of packets.

  Proceeding to step S155, the processor 13 of the numerical controller 1 determines whether or not reception of all packets of all servo control responses from the servos 3 and 4 has been completed. When the servo control response packet to be received remains (No in step S155), the processor 13 returns to step S105 and resumes the execution of the normal process until the packet reception in the immediately preceding step S150 is completed. When the packet reception in step S150 is completed, the first communication interface 14 outputs a servo response reception interrupt request (not shown) to the processor 13, and the processor 13 that has detected this returns to step S150 and returns to the rest. Receive the packet.

  When the processor 13 of the numerical controller 1 completes reception of all packets of all servo control responses from the servos 3 and 4 (Yes in step S155), the processor 13 returns to step S105 and resumes execution of normal processing. At this time, normally, both of the servo command transmission process and the servo response reception process are completed, and the processor 13 continues to execute the normal process of step S105 until the next interrupt request is input. .

  If it is determined in step S120 that the interrupt request input immediately before is the third interrupt request (No in step S120), the process proceeds to the next step S160.

  In step S160, the processor 13 of the numerical controller 1 increments the value of the counter variable C by 1, and proceeds to the next step S165.

  In step S165, the processor 13 of the numerical controller 1 determines whether the value of the counter variable C at this time is 1 or 2. In other words, it is determined whether the third interrupt request input immediately before is input first or second in the current servo synchronization period. If the value of the counter variable C at this time is 1, it is regarded as the start timing of the peripheral device processing, and the process proceeds to step S170.

  In step S170, the processor 13 of the numerical controller 1 determines whether or not the same determination as in step S155, that is, the servo response reception process in the current servo synchronization period has already been completed. If the servo response reception processing has not been completed yet at this point (No in step S170), it is considered that good synchronization control cannot be performed with the setting in the current servo synchronization period, and the error processing in step S135 is performed. After that, this flow is finished. If the servo response reception process is completely completed at this time (Yes in step S170), the process proceeds to the next step S175.

  In step S175, the processor 13 of the numerical controller 1 starts peripheral device processing. Here, if there are a plurality of peripheral device processes, the peripheral device scheduler is provided here, and each time the first third interrupt is received, the processing is started in order. Details are omitted. When the second third interrupt request is input, the process returns to step S120.

  In the determination of step S165, if the value of the counter variable C at this time is 2, the processor 13 regards it as the end timing of the peripheral device processing, and proceeds to step S180.

  In step S180, the processor 13 of the numerical controller 1 performs a so-called suspend process in which the execution of the peripheral device process that has been continued is interrupted. When the peripheral device processing is started in the next servo synchronization control, the continuation is resumed.

  Moving to step S185, the processor 13 of the numerical control apparatus 1 executes a servo command generation process. In the servo command generation process, based on the servo control responses of the servos 3 and 4 received in step S150, the control operation amount to be controlled by the servos 3 and 4 is calculated in the next servo synchronization period. Generate control commands. After the servo command generation process ends, the process returns to step S105 to continue normal processing.

  By performing the synchronization process according to the above control procedure, the following advantages can be obtained. Since command data and response data sent and received between the numerical controller 1 and each servo are transmitted by Ethernet (registered trademark) or serial communication as in the example of the present embodiment, an interrupt request from the first communication interface 14 is received. On the other hand, the processor 13 needs to cope with high priority. Since data is transmitted and received between the processor 13 and the servos 3 and 4 in a packet unit many times, it is necessary to respond to transmission / reception interrupt requests with such a high frequency. On the other hand, in the above synchronous process, the servo command transmission process and the servo response reception process are intensively handled in the first several equally divided sections of the servo synchronization period, and other priorities in the subsequent equally divided sections. Dedicated to high peripheral processing. It is possible to execute the processes without affecting each other by avoiding the duplication of both processes having high priorities, and the overhead (unnecessary processing time) of the processor 13 can be reduced.

  As described above, in the present embodiment, the first interrupt request by the system control cycle timer 111 that informs the time to the normal real-time OS is in response to the servo synchronization cycle of the servos 3 and 4 by the servo synchronization cycle timer 122. It can be set sufficiently large. The servo control command to the servos 3 and 4 can be transmitted in synchronization with the servos 3 and 4 without making the first interrupt request by the system clock on the real-time OS fine. A control section in which the second interrupt request for the transmission / reception processing of the servos 3 and 4 is not generated can be reliably obtained in the form of the third interrupt request.

  According to the present embodiment, it is possible to stably and surely allocate a certain proportion of the processing of the processor 13 to the control processing of the peripheral device without complicating software and hardware.

  Particularly in this embodiment, the servo synchronous cycle interrupt generator 123 generates the second interrupt request at a cycle shorter than the cycle of the first interrupt request generated by the system control cycle interrupt generator 112. Servo control commands to the servos 3 and 4 in the second interrupt request by the servo synchronization period interrupt generator 123 without making the first interrupt request by the system control period interrupt generator 112 according to the system clock on the real-time OS fine. Can be reliably transmitted in synchronization with the servos 3 and 4.

  Particularly in this embodiment, in order for the numerical controller 1 to periodically perform synchronous communication between the servos 3 and 4 and the processor 13, the servo communication bus 2 connected to the servos 3 and 4 and the processor 13 The first communication interface 14 for performing input / output control, the servo synchronization period and phase of the servo synchronization period timer 122, that is, the servo synchronization period setting unit 121 that can change the start timing, the servo communication bus 2, and the servo synchronization period setting Servo control cycle setting unit 32 that can change the servo control cycle and start timing of servo control cycle timer 33 that generates the operation timing of second communication interface 15 and servos 3 and 4 for performing input / output control with device 121. On the other hand, the same length of time as the servo synchronization period for synchronizing the processor 13 and the servos 3 and 4 is used. The servo control cycle and start timing are set via the servo communication bus 2 and the servo synchronization cycle and start timing for synchronizing the processor 13 and the servo synchronization cycle interrupt generator 123 to the servo synchronization cycle setter 121 are set. A synchronization cycle setting command unit 137 that is set via the servo communication bus 2 is further provided.

  The synchronization between the second interrupt request and the third interrupt request by the servo synchronization period interrupt generator 123 can be reliably set through the servo communication bus 2.

  The servo synchronization period setting unit 121 and the servo control period setting unit 32 can use the same or similar hardware capable of changing the period and the start timing for its own timer. Usually, the software does not bloat in that the synchronization cycle setting command unit 137 for the servo control cycle setting device 32 provided in the numerical control device is also used for the servo synchronization cycle setting device 121.

  In the present embodiment, the network form of the servo communication bus 2 in which the processor 13 sends and receives data to and from the servo synchronization interrupt circuit 12 and each of the servos 3 and 4 is as shown in FIG. On the other hand, it is a form to send and receive individually. The present invention is not limited to this, and for example, as shown in FIG. 8, the processor 13 and each device may be connected in the form of a ring network. In this case, the processor 13 transmits a packet of servo control commands connected to one, and each device takes only necessary command data from the one connected packet and is necessary for a series of connected packets. The reply data is added and transmitted to the next ring network destination. In this configuration, the calculation method in steps S25 and S30 in the flow of FIG. 4 needs to be appropriately changed.

  Particularly in this embodiment, since the servo synchronization circuit 12 always transmits a series of connected packets to the processor 13 to the processor 13 last, the servo synchronization circuit 12 determines the servo response reception timing of the processor 13 as its transmission timing. The servo synchronization period interrupt generator 123 can automatically avoid the congested section of the servo communication bus 2 among a plurality of equally divided sections and generate a third interrupt request to the processor 13. Without increasing the load on the processor 13, it is possible to stably distribute a certain proportion of the processing of the processor 13 to the control processing of the peripheral devices.

1 Numerical control device 2 Servo communication bus 3, 4 Servo (servo motor)
11 Interrupt circuit for system control 12 Interrupt circuit for servo synchronization 13 Processor (calculation means)
14 First communication interface (first communication interface means)
15 Second communication interface (second communication interface means)
31 Servo communication interface 32 Servo control cycle setting device (servo timer setting means)
33 Servo control cycle timer (servo timer)
34 Servo controller 111 System control cycle timer (first timer)
112 System control cycle interrupt generator (first interrupt generation means)
121 Servo synchronization cycle setting device (second timer setting means)
122 Servo synchronization cycle timer (second timer)
123 Servo synchronization period interrupt generator (second interrupt generating means, third interrupt generating means)
123a Timer period divider (dividing means)
131 Real-time OS scheduler 132 Normal processing unit 133 Interrupt scheduler 134 Peripheral device processing unit 135 Servo command generation unit 136 Servo transmission / reception processing unit 137 Synchronization cycle setting command unit (timer setting means)

Claims (6)

A machine tool main body provided with a servo motor for moving a tool or a workpiece, and a numerical control device for controlling a plurality of operations related to predetermined peripheral devices related to the machine tool main body by multitasking,
Computing means;
A first timer;
First interrupt generation means for generating a first interrupt corresponding to the period of the operation clock of the calculation means at a predetermined cycle when the first timer counts;
A second timer different from the first timer;
Second interrupt generating means for generating a second interrupt for transmitting / receiving servo data to / from the servo motor with respect to the calculating means at a predetermined cycle when the second timer counts;
Dividing means for dividing the period of the second interrupt by the second interrupt generating means into a plurality of predetermined sections;
And a third interrupt generation means for causing the arithmetic means to generate a third interrupt for controlling the peripheral device at the start of a predetermined section among the plurality of sections divided by the dividing means. Characteristic numerical control device. The numerical control device according to claim 1,
The second interrupt generation means includes
The numerical controller according to claim 1, wherein the second interrupt is generated in a cycle shorter than a cycle of the first interrupt generated by the first interrupt generation unit. In the numerical control device according to claim 1 or 2,
A first communication interface means for performing input / output control between the servo communication bus connected to the servo motor and the calculation means in order to perform synchronous communication periodically between the servo motor and the calculation means; ,
Second timer setting means capable of changing the cycle and timing of the second timer;
Second communication interface means for performing input / output control between the servo communication bus and the second timer setting means;
For the servo timer setting means that can change the period and timing of the servo timer that generates the operation timing of the servo motor, the period and timing for synchronizing the arithmetic means and the servo motor are set via the servo communication bus. Timer setting means for setting, via the servo communication bus, a cycle and timing for synchronizing the arithmetic means with the second interrupt generating means and the third interrupt generating means with respect to the second timer setting means; The numerical control device further comprising: In the numerical control device according to any one of claims 1 to 3,
The third interrupt generation means includes
The numerical control apparatus, wherein the arithmetic unit generates the third interrupt while avoiding a congested section of the servo communication bus among the plurality of sections. A machine tool control method for controlling a plurality of operations related to a machine tool main body provided with a servo motor for moving a tool or a workpiece and a predetermined peripheral device related to the machine tool main body by multitasking. ,
A procedure for generating a first interrupt according to a cycle of an operation clock of an arithmetic means provided in the machine tool at a predetermined first cycle;
Generating a second interrupt for transmitting / receiving servo data to / from the servo motor at a predetermined second period different from the first period;
Dividing the period of the second interrupt into a plurality of predetermined sections;
A machine tool control comprising: a step of generating a third interrupt for controlling the peripheral device to the computing means at a start of a predetermined section among the plurality of divided sections. Method. A machine tool control program for controlling a plurality of operations related to a machine tool main body having a servo motor for moving a tool or a workpiece and a predetermined peripheral device related to the machine tool main body in a multitasking manner. There,
On the computer,
A procedure for generating a first interrupt according to a cycle of an operation clock of an arithmetic means provided in the machine tool at a predetermined first cycle;
Generating a second interrupt for transmitting / receiving servo data to / from the servo motor at a predetermined second period different from the first period;
Dividing the period of the second interrupt into a plurality of predetermined sections;
A step of causing the arithmetic means to generate a third interrupt for controlling the peripheral device at the start of a predetermined section of the plurality of divided sections. Control program.

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