ENGINE CONTROL DEVICE, MACHINING SYSTEM, ENGINE CONTROL METHOD AND MACHINING METHOD

Abstract

A motor control device (10A), which generates a control signal for a motor driving a drive shaft based on an acceleration time constant and a deceleration time constant, includes a synchronous operation command extraction unit (11) that extracts blocks from a machining program (2) in which a setpoint control for the drive shafts, which run synchronously, is continuously commanded, and extracts synchronous operation commands contained in the blocks; an operating state calculation unit (12) that calculates, based on an acceleration time constant and a deceleration time constant, an operating time and an energy consumption associated with the machining carried out with the machining program (2);an optimal parameter calculation unit (14) that calculates, for each synchronous operating command, the acceleration time constant and the deceleration time constant that ensure the operating time of the drive shaft is within the permissible operating time, which represents a permissible time for operation, and that the energy consumption is minimal, as optimal parameters; and a motor control unit (15) that generates the control signal for the motor based on the optimal parameters.

Description

Technical area

[0001] The present disclosure relates to an engine control device that controls engines, and also relates to a machining system, an engine control method and a machining method. State of the art

[0002] A motor control device is a device that controls a spindle motor, which rotates a tool or workpiece, and feed shaft motors, which move the tool or workpiece, thus causing a numerically controlled machine tool to machine the workpiece. This motor control device uses converters and inverters to control the motors, such as the spindle motor and the feed shaft motors. The total energy consumption of a drive system that includes the converters, inverters, and motors can be expressed as the sum of the motor power and losses in the converters, inverters, and motors. In this case, conduction losses and switching losses of converter diodes included in the converters, conduction losses and switching losses of inverter diodes included in the inverters, and copper losses in the servo motors decrease with decreasing motor drive currents.However, reducing the motor drive current generally involves a trade-off with reducing the acceleration and deceleration times. Therefore, setting smaller drive currents leads to a longer cycle time.

[0003] A control device described in patent literature 1 calculates a parameter set using energy consumption and cycle time as indicators, which is used when setting operating instruction patterns for motors and executes a machining program based on the calculated parameter set, thereby reducing energy consumption. List of quotations Patent literature

[0004] Patent literature 1: Japanese publication no. 2010-240800 Brief description of the inventionProblem to be solved by the invention

[0005] However, one problem with the technique described above in patent literature 1 is that the energy consumption for a process other than machining, such as a tool change, cannot be reduced, since the single parameter set is set for the entire machining program.

[0006] The present disclosure was prepared in light of the foregoing, and one objective of the present disclosure is to obtain a motor control device capable of setting parameters for an operation other than machining, enabling a shorter cycle time and reduced energy consumption. Means to solve the problem

[0007] To solve the aforementioned problem and fulfill the task, a motor control device according to the present disclosure generates a control signal for a motor that drives the drive shaft based on an acceleration time constant, which defines an acceleration time of a drive shaft, and a deceleration time constant, which defines a deceleration time of the drive shaft. The motor control device includes a synchronous operation command extraction unit, which extracts blocks from a machining program in which setpoint control is to be continuously commanded for a plurality of drive shafts running synchronously, and extracts synchronous operation commands contained in the blocks.Furthermore, the motor control device according to the present disclosure includes an operating state calculation unit that calculates an operating time and energy consumption associated with the machining operation to be performed by the machining program, based on an acceleration time constant and a deceleration time constant. The motor control device according to the present disclosure also includes an optimal parameter calculation unit that calculates the acceleration time constant and the deceleration time constant as optimal parameters for each of the synchronous operating commands, ensuring that the operating time of the drive shaft is within a permissible operating time, which represents a permissible operating time, and that the energy consumption is minimal; and a motor control unit that generates the control signal for the motor based on the optimal parameters. Effects of the invention

[0008] The motor control device according to the present disclosure has the effect of setting parameters for an operation other than machining, which enable a shorter cycle time and reduced energy consumption. Brief description of the drawings Fig. Figure 1 is a functional diagram of an engine control device according to a first embodiment. Fig. Figure 2 is a representation used to explain synchronous operating commands extracted by the motor control device according to the first embodiment. Fig. Figure 3 is a representation illustrating an example of a command pattern for a drive shaft used by the engine control device according to the first embodiment. Fig. Figure 4 is a representation used to explain operating conditions calculated by the motor control device according to the first embodiment for a feed shaft. Fig. Figure 5 is a representation used to explain operating states calculated by the motor control device according to the first embodiment for a spindle. Fig. Figure 6 is a representation illustrating a configuration example of an operating state table that the motor control device stores according to the first embodiment. Fig. Figure 7 is a flowchart illustrating a procedure of a process carried out by an operating state calculation unit of the motor control device according to the first embodiment. Fig. Figure 8 is a representation used to explain a process by which the motor control device according to the first embodiment extracts combinations of acceleration time constants and deceleration time constants based on a permissible operating time. Fig. Figure 9 is a representation used to explain a process by which the motor control device according to the first embodiment extracts a combination of an acceleration time constant and a deceleration time constant based on energy consumption. Fig. Figure 10 is a representation illustrating an operating time resulting from a surface approximation performed by the motor control device according to the first embodiment. Fig. Figure 11 is a representation illustrating the energy consumption resulting from the area approximation performed by the motor control device according to the first embodiment. Fig. Figure 12 is a flowchart illustrating a procedure of a process carried out by an optimal parameter calculation unit of the motor control device according to the first embodiment. Fig. Figure 13 is a representation illustrating first exemplary command patterns using optimal parameters calculated by the motor control device according to the first embodiment. Fig. Figure 14 is a representation illustrating first exemplary power waveforms resulting from the use of the optimal parameters calculated by the motor control device according to the first embodiment. Fig. Figure 15 is a representation illustrating second exemplary command patterns using optimal parameters calculated by the motor control device according to the first embodiment. Fig. Figure 16 is a representation illustrating second exemplary power waveforms resulting from the use of the optimal parameters calculated by the motor control device according to the first embodiment. Fig. Figure 17 is a flowchart illustrating a procedure of a process carried out by the motor control device according to the first embodiment. Fig. Figure 18 is a functional diagram of an engine control device according to a second embodiment. Fig. Figure 19 is a representation illustrating first exemplary power waveforms resulting from the use of optimal parameters calculated by the engine control device according to the second embodiment, taking into account a range for total power values. Fig. Figure 20 is a representation illustrating second exemplary power waveforms resulting from the use of optimal parameters calculated taking into account the range for total power values ​​by the engine control device according to the second embodiment. Fig. Figure 21 is a functional diagram of a machining system according to a third embodiment. Fig. Figure 22 is a flowchart illustrating a procedure of a process carried out by the processing system according to the third embodiment. Fig. Figure 23 is a representation illustrating a configuration example of a processing circuit implemented with a processor and a memory as the processing circuit of the motor control device, according to each of the first to third embodiments. Fig. Figure 24 is a representation illustrating an example of a processing circuit configured as dedicated hardware to serve as the processing circuit of the motor control device, according to each of the first to third embodiments. Description of embodiments

[0009] With reference to the drawings, a detailed description of engine control devices, machining systems, engine control methods and machining methods according to embodiments of the present disclosure is provided below in this document. First embodiment.

[0010] Fig. Figure 1 is a functional diagram of an engine control device according to a first embodiment.

[0011] The motor control device 10A is a computer that controls a machining unit 3 which includes motors 4. Based on a machining program 2 created by a computer-aided manufacturing (CAM) system or the like, the motor control device 10A generates and outputs control signals for the motors 4 that drive the drive shafts.

[0012] The machining device 3 processes a workpiece (work material) by operating the motors 4 according to the control signals for the motors 4. The machining device 3 is, for example, a machine tool arranged in a production plant. The motor control device 10A includes a numerical control device for performing numerical control of the machining device 3. The drive shafts driven by the motors 4 include, for example, a spindle, feed shafts, and rotary shafts. In the first embodiment, the machining device 3 is described as having the spindle and the feed shafts.

[0013] The spindle is a shaft used to rotate a tool or the workpiece. The feed shafts include feed shafts (later described as tool feed shafts) that move the tool, and a feed shaft (later described as a workpiece feed shaft) that moves the workpiece.

[0014] The motor control device 10A can be located near the machining unit 3 or installed on a server or the like that is located remotely from the machining unit 3. The motor control device 10A includes a synchronous operation command extraction unit 11, one or more synchronous operation command units, and a motor control unit 15. The motor control device 10A, which is located in Fig. As illustrated in Figure 1, the synchronous operating command units A1 to An (where n is a natural number) are included as the synchronous operating command units. The motor control device 10A is described below as having the synchronous operating command units A1 and A2 as the synchronous operating command units.

[0015] For each of the synchronous operating commands, each of the synchronous operating command units A1 and A2 calculates optimal parameters and sends the calculated optimal parameters to the motor control unit 15. If there are more synchronous operating commands than synchronous operating command units, the synchronous operating command units share optimal parameter calculations for the synchronous operating commands. In other words, the synchronous operating command unit that has completed the optimal parameter calculation performs the optimal parameter calculation on an unprocessed synchronous operating command. In the motor control device 10A, such a process is repeated by the synchronous operating command units.

[0016] Each of the synchronous operating command units A1 and A2 includes an operating state calculation unit 12, a permissible operating time input unit 13, and an optimal parameter calculation unit 14. The extraction unit for synchronous operating commands 11 is connected to the operating state calculation units 12 of the synchronous operating command units A1 and A2. The motor control unit 15 is connected to the optimal parameter calculation units 14 of the synchronous operating command units A1 and A2.

[0017] In each of the synchronous operating command units A1 and A2, the operating state calculation unit 12 and the input unit of the permissible operating time 13 are connected to the optimal parameter calculation unit 14.

[0018] The machining program 2, generated by the CAM system or similar, is input into the synchronous operation command extraction unit 11. The synchronous operation command extraction unit 11 receives the machining program 2. The synchronous operation command extraction unit 11 analyzes the input machining program 2 and extracts from blocks (where several blocks form a series of commands) contained in the machining program 2 blocks (where a group contains a set of synchronous operation commands) in which the setpoint control for two or more of the drive shafts, which run synchronously, is to be continuously commanded. Furthermore, the synchronous operation command extraction unit 11 extracts the synchronous operation commands contained in the extracted blocks. Setpoint control refers to a control that brings a control variable close to a setpoint.

[0019] The extraction unit for synchronous operating commands 11 determines that positioning commands for the feed shafts (the tool feed shafts in the first embodiment) and a command for constant rotation of the spindle are intended for setpoint control, and thus the synchronous operating commands are extracted. In other words, the commands extracted as synchronous operating commands in the first embodiment are a combination of positioning commands for the tool feed shafts and a command for constant rotation of the spindle to be subjected to setpoint control. In cases where the machining device 3 includes the rotating shafts, positioning commands for the rotating shafts, if included in synchronous operating commands, are extracted by the extraction unit for synchronous operating commands 11 as synchronous operating commands.

[0020] Based on M-code commands, the extraction unit for synchronous operation commands 11 extracts from the machining program 2 a motion block for moving to a tool change position before a tool change and a motion block for moving to the next machining position after the tool change as synchronous operation commands. In other words, the extraction unit for synchronous operation commands 11 extracts the motion block (first motion block) for moving from a machining end position, where machining before the tool change ends, to the tool change position, where the tool change is performed, as the synchronous operation command.The extraction unit for synchronous operating commands 11 extracts the motion block (second motion block) for the movement from a tool change end position, where the tool change ends, to the machining start position, where machining is next performed after the tool change, as the synchronous operating command. For example, the extraction unit for synchronous operating commands 11 extracts at least one of the first motion block or the second motion block as the synchronous operating command(s).

[0021] This section provides a description of synchronous operating commands extracted by the synchronous operating command extraction unit 11 of the motor control device 10A. Fig. Figure 2 is a representation used to explain the synchronous operating commands extracted by the motor control device according to the first embodiment. Fig. Figure 2 illustrates an example of the processing program 2 and a result of a synchronous operation instruction extraction process performed by the synchronous operation instruction extraction unit 11.

[0022] The processing program 2 contains several lines of alphanumeric characters, each line specifying a command for the processing device 3. The alphanumeric characters at the left end of the processing program 2 in Fig. 2 are the line numbers of processing program 2. For example, processing program 2 contains commands with line numbers N58 to N64.

[0023] The command at N59 represents a spindle stop command, and the command at N60 represents a tool change command. Specifically, the command at N59 and the command at N60 are synchronous operation commands (i-0) for moving the spindle to a tool change position while the spindle movement is delayed. Therefore, the synchronous operation command extraction unit 11 extracts the command at N59 and the command at N60 from the machining program 2 as the synchronous operation commands (i-0).

[0024] The commands at N61 to N63 in machining program 2 represent a positive rotation of the spindle, a positioning of the X and Y axes, and a positioning of the Z axis, respectively. Specifically, the commands at N61 to N63 are synchronous operation commands (i) for moving the spindle to a machining start position while the spindle is being accelerated. Therefore, the extraction unit for synchronous operation commands 11 extracts the commands at N61 to N63 in machining program 2 as the synchronous operation commands (i).

[0025] Each operating state calculation unit 12 calculates operating states for the drive shaft. The operating state calculation unit 12 calculates the operating states based on several preset acceleration time constants and several preset deceleration time constants. The acceleration time constant is a time constant that defines an acceleration time of the drive shaft, and the deceleration time constant is a time constant that defines a deceleration time of the drive shaft. The acceleration time constant is expressed as the time measured from the time acceleration begins until the time a command velocity is reached as the target velocity, and the deceleration time constant is expressed as the time measured from the time deceleration begins until the time a velocity of 0 is reached.The acceleration and deceleration time constants, which are preset, can be uniform or vary between the drive shafts. The acceleration and deceleration time constants are preset externally by a user in each operating state calculation unit 12.

[0026] This section provides a description of an example of a drive shaft command pattern used by the 10A motor control device. Fig. Figure 3 is a representation illustrating an example of a drive shaft command pattern used by the engine control device according to the first embodiment. A diagram shown in Fig. Figure 3 illustrates time on a horizontal axis and velocity on a vertical axis.

[0027] Fig. Figure 3 is the diagram that schematically illustrates the command pattern for the drive shaft. As shown in Fig. As illustrated in Figure 3, the command pattern is determined by a command speed specified in the machining program 2, an acceleration time constant c1, and a deceleration time constant d1. The drive shaft is to accelerate, or gain speed, according to the acceleration time constant c1 until it reaches the command speed specified in the machining program 2 and is driven at this command speed. Subsequently, the drive shaft is to decelerate according to the deceleration time constant d1 and come to a stop.

[0028] Based on each instruction pattern, the operating state calculation unit 12 calculates an operating time and energy consumption for the drive shaft as operating states. The operating state calculation unit 12 can also calculate a power waveform for the drive shaft as an additional operating state, besides the operating time and energy consumption.

[0029] Fig. Figure 4 is a representation used to explain operating conditions calculated for the feed shaft by the motor control device according to the first embodiment. Fig. Figure 4 is the diagram that schematically illustrates the operating states calculated for the feed shaft by the operating state calculation unit 12. A diagram shown in an upper part of Fig. Figure 4 illustrates time on a horizontal axis and the feed shaft velocity on a vertical axis. A diagram shown in a lower part of Fig. Figure 4 illustrates time on a horizontal axis and power for the feed shaft (feed shaft power) on a vertical axis.

[0030] A feed shaft operating time Ft1, or feed shaft operating time, is the time measured from the moment a positioning command is issued until the positioning is completed. The feed shaft is to be accelerated, or gain speed, according to a feed shaft acceleration time constant Fc1, which is an acceleration time constant for the feed shaft, until a command speed specified in the machining program 2 is reached, and is to be driven at this command speed. Subsequently, the feed shaft is to be decelerated and come to a stop according to a feed shaft deceleration time constant Fd1, which is a deceleration time constant for the feed shaft.

[0031] A feed shaft power waveform Fw1, a power waveform of the feed shaft, is a collection of power values ​​sampled during the operating time of the feed shaft. The feed shaft consumption energy Fe1, the consumption energy of the feed shaft, is an integral value of the power sampled during the operating time of the feed shaft.

[0032] Fig. Figure 5 is a representation used to explain operating states calculated for the spindle by the motor control device according to the first embodiment. Fig. Figure 5 is the diagram that schematically illustrates the operating states calculated for the spindle by the operating state calculation unit 12. A diagram shown in an upper part of Fig. Figure 5 illustrates time on a horizontal axis and spindle speed on a vertical axis. A diagram shown in the lower part of Fig. Figure 5 illustrates time on a horizontal axis and the power for the spindle (spindle power) on a vertical axis.

[0033] A spindle operating time Mt1, or spindle operating time, is the time measured from the moment a rotation command is issued until the spindle speed reaches the command speed. The spindle speed is expected to increase according to a spindle acceleration time constant Mc1, which is an acceleration time constant for the spindle.

[0034] A spindle power waveform Mw1, a power waveform of the spindle, is a collection of power values ​​sampled during the spindle's operating time. The spindle energy consumption Me1, an energy consumption value of the spindle, is an integral value of the power sampled during the spindle's operating time.

[0035] The operating state calculation unit 12 calculates operating states by simulation using an instruction pattern and a simulation model of a system that includes the motors 4 and the drive shafts. The operating state calculation unit 12 can calculate operating states using a machine learning model generated from accumulated data of previously calculated operating states. The operating state calculation unit 12 can calculate operating states by measuring operating time with a timer and measuring power waveforms and energy consumption with a power meter.

[0036] The operating state calculation unit 12 stores the calculated operating states, along with the acceleration and deceleration time constants used in the calculation, in an operating state table, which will be described later. The operating state calculation unit 12 includes a memory (not illustrated) or the like that stores the operating state table. The memory that stores the operating state table may be located outside the operating state calculation unit 12.

[0037] For each of the drive shafts, a minimum value, a maximum value, and increments of each of the acceleration and deceleration time constants are predefined in each operating state calculation unit 12. In the operating state table, a total number of combinations of the acceleration time constants and the deceleration time constants corresponds to a table number. Each operating state calculation unit 12 can create an operating state table in which the increments of the acceleration time constant and the increments of the deceleration time constant are not uniform, and can store calculated operating states in the operating state table.

[0038] The acceleration and deceleration time constants in the operating state table are set by the user. The user can set the minimum values, maximum values, and increments of the acceleration and deceleration time constants in the operating state calculation units 12, or set acceleration and deceleration time constants in non-uniform increments in the operating state calculation units 12.

[0039] Fig. Figure 6 is a representation illustrating a configuration example of the operating state table stored by the motor control device according to the first embodiment. Fig. Figure 6 illustrates the example for the operating state table 51, which contains operating states that are stored by the operating state calculation unit 12.

[0040] Operating state table 51 is a drive shaft-specific table in which the acceleration time constant, the deceleration time constant, the operating time, the energy consumption, and the power waveform are assigned. For the power waveform, sampled power values, taken at specific intervals within the operating time of the drive shaft, are stored.

[0041] In Fig. 6. The minimum value, the maximum value and each increment of each of the acceleration and deceleration time constants are 100, 2000 and 100 respectively, with the total number of combinations of the acceleration time constants and the deceleration time constants being 400.

[0042] For each of the combinations of acceleration time constants and deceleration time constants stored in the operating state table 51, the operating state calculation unit 12 calculates the operating time, the energy consumed, and the power waveform as operating states and stores these calculation results in the operating state table 51. The operating state calculation unit 12 generates the operating state table 51, as shown, for example, in Fig. Figure 6 illustrates this for each synchronous operation instruction included in the set (for each block).

[0043] This section provides a description of a procedure by which the operating state calculation unit 12 generates the operating state table 51. Fig. Figure 7 is a flowchart illustrating the procedure of the process carried out by the operating state calculation unit of the motor control device according to the first embodiment. Fig. Figure 7 illustrates an exemplary operating sequence of the operating state calculation unit 12. The operating state calculation unit 12 executes the process that is described in Fig. Figure 7 illustrates for each synchronous operation instruction that is included in the set (for each block).

[0044] The operating state calculation unit 12 sets ii, which specifies a row number in the operating state table 51, to 1 (step S1). The operating state calculation unit 12 sets the acceleration time constant and the deceleration time constant from a ii-th row of the operating state table 51 (step S2) and calculates the operating states using the set acceleration and deceleration time constants (step S3).

[0045] The operating state calculation unit 12 stores the calculated operating states in the ii-th row of the operating state table 51 (step S4). The operating state calculation unit 12 determines whether the operating states have been stored up to the last row of the operating state table 51 or not (step S5).

[0046] If the operating state calculation unit 12 determines that the operating states have not been stored up to the last row of the operating state table 51 (step S5, No), the operating state calculation unit 12 sets ii to ii+1 (step S6). The operating state calculation unit 12 then performs the operations of steps S2 to S5.

[0047] The operating state calculation unit 12 repeats the operation from step S6 and the operations from steps S2 to S5 until the operating state calculation unit 12 determines that the operating states have been stored up to the last line of the operating state table 51.

[0048] When the operating state calculation unit 12 determines that the operating states up to the last row of the operating state table 51 have been stored (step S5, Yes), the operating state calculation unit 12 terminates the process of generating the operating state table 51. The operating state calculation unit 12 can calculate and store the operating states for each row of the operating state table 51 in any order.

[0049] The operating state calculation unit 12 stores the operating state table 51, in which the operating states are stored up to the last row. The operating state calculation unit 12 sends the operating state table 51, in which the operating states are stored up to the last row, to the optimal parameter calculation unit 14.

[0050] The input unit for permissible operating time 13 stores a buffer time for the operating time and inputs the stored buffer time into the optimal parameter calculation unit 14. A minimum operating time calculated by the operating state calculation unit 12, plus the buffer time input by the input unit for permissible operating time 13, constitutes a permissible operating time. This permissible operating time can be calculated by the input unit for permissible operating time 13 and input into the optimal parameter calculation unit 14, or it can be calculated by the optimal parameter calculation unit 14.

[0051] In cases where the allowable operating time input unit 13 calculates the allowable operating time, the allowable operating time input unit 13 calculates the sum of the minimum operating time calculated by the operating state calculation unit 12 and the buffer time as the allowable operating time and inputs the calculated allowable operating time into the optimal parameter calculation unit 14.

[0052] In cases where the optimal parameter calculation unit 14 calculates the allowable operating time, the optimal parameter calculation unit 14 calculates the sum of the minimum operating time calculated by the operating state calculation unit 12 and the buffer time entered by the allowable operating time input unit 13 as the allowable operating time.

[0053] The input unit for permissible operating time 13 can input an externally entered permissible operating time into the optimal parameter calculation unit 14. The externally entered permissible operating time is longer than the minimum operating time calculated by the operating state calculation unit 12.

[0054] For each synchronous operating command, the optimal parameter calculation unit 14 calculates, based on the operating state table 51 generated by the operating state calculation unit 12, an optimum acceleration time constant for the drive shaft (hereinafter referred to as an optimal acceleration time constant) and an optimum deceleration time constant for the drive shaft (hereinafter referred to as an optimal deceleration time constant) as optimal parameters. The optimal parameter calculation unit 14 calculates the combination of the acceleration time constants and the deceleration time constants that results in minimal energy consumption in a range where the operating time falls within the permissible operating time, as the combination of the optimal acceleration time constants and the optimal deceleration time constants.In the first embodiment, the optimal acceleration time constant and the optimal deceleration time constant, which are calculated in combination by the optimal parameter calculation unit 14, are defined as the optimal parameters.

[0055] Fig. Figure 8 is a representation used to explain a process by which the motor control device according to the first embodiment extracts combinations of acceleration time constants and deceleration time constants based on the permissible operating time. Fig. Figure 8 is the representation that schematically illustrates the operating times corresponding to the combinations of acceleration time constants and deceleration time constants obtained by the optimal parameter calculation unit 14. A diagram shown in Fig. Figure 8 illustrates the acceleration time constant on a horizontal axis, the deceleration time constant on a vertical axis, and the operating time on a depth axis. A plane in Fig. Figure 8 represents the permissible operating time At1. The combinations of the acceleration time constants and the deceleration time constants are represented by white dots c2 and black dots c3.

[0056] The black points c3 are points that each result in the operating time being within the permissible operating time At1, and the white points c2 are points that each result in the operating time being outside the permissible operating time At1. In other words, the combinations of the acceleration time constants and the deceleration time constants within the permissible operating time At1 are represented by the black points c3, and the combinations of the acceleration time constants and the deceleration time constants outside the permissible operating time At1 are represented by the white points c2.

[0057] The optimal parameter calculation unit 14 extracts data from the operating state table 51 that includes the operating times within the permissible operating time At1. In other words, based on the permissible operating time At1, the optimal parameter calculation unit 14 extracts the row data corresponding to the black points c3 from the operating state table 51. Next, the optimal parameter calculation unit 14 further extracts data from the extracted data—that is, the data containing the operating times within the permissible operating time—that includes data indicating minimal energy consumption.

[0058] Fig. Figure 9 is a representation used to explain a process by which the motor control device according to the first embodiment extracts the combination of the acceleration time constants and the deceleration time constants based on the energy consumed. Fig. Figure 9 is the representation that schematically illustrates the energy consumption corresponding to the combination of the acceleration time constants and the deceleration time constants obtained by the optimal parameter calculation unit 14. A diagram that is in Fig. Figure 9 illustrates the acceleration time constant on a horizontal axis, the deceleration time constant on a vertical axis, and the energy consumed on a depth axis. Fig. 9 the combinations of the acceleration time constants and the deceleration time constants are represented by white dots c4 and black dots c5.

[0059] Each of the black dots c5 indicates the energy consumption corresponding to the combination of the acceleration and deceleration time constants that results in the operating time being within the permissible operating time. Each of the white dots c4 indicates the energy consumption corresponding to the combination of the acceleration and deceleration time constants that results in the operating time being outside the permissible operating time. A diamond-shaped dot c6, located in Fig. The point represented by the diamond-shaped point c6, shown in Figure 9, indicates that the energy consumption is minimal in the range where the operating time falls within the permissible operating time. The optimal parameter calculation unit 14 calculates the combination of the acceleration time constant and the deceleration time constant, represented by the diamond-shaped point c6, as the combination of the optimal acceleration time constant and the optimal deceleration time constant.

[0060] The optimal parameter calculation unit 14 can apply an area approximation to discrete distributions of operating time and energy consumption with respect to the combinations of acceleration time constants and deceleration time constants obtained from the operating state table 51. In other words, the optimal parameter calculation unit 14 can generate, as variables, for each of the two or more drive shafts, the discrete distributions exhibiting the operating time and energy consumption corresponding to the acceleration time constant and deceleration time constant, and apply the area approximation to the discrete distributions.

[0061] By applying the area approximation to the discrete distributions, the optimal parameter calculation unit 14 obtains an approximation surface that expresses one function of the operating time and the energy consumption as a continuous function of the other function of the operating time and the energy consumption corresponding to the acceleration time constant and the deceleration time constant. In this case, based on the approximation surface, the optimal parameter calculation unit 14 calculates a combination of an acceleration time constant and a deceleration time constant that results in the energy consumption being minimal in a range where the operating time falls within the permissible operating time, as the combination of the optimal acceleration time constant and the optimal deceleration time constant.

[0062] Fig. Figure 10 is a representation illustrating the operating time resulting from the surface approximation performed by the motor control device according to the first embodiment. Fig. Figure 11 is a representation illustrating the energy consumption resulting from the area approximation performed by the motor control device according to the first embodiment. Fig. Figure 10 illustrates the operating time resulting from the area approximation performed by the optimal parameter calculation unit 14, with respect to the combinations of the acceleration time constants and the deceleration time constants, that is, the exemplary result of the area approximation applied to the operating time. Fig. Figure 11 illustrates the energy consumption resulting from the area approximation performed by the optimal parameter calculation unit 14, with respect to the combinations of the acceleration time constants and the deceleration time constants, that is, the exemplary result of the area approximation applied to the energy consumption.

[0063] A diagram that is in Fig. Figure 10 illustrates the acceleration time constant on a horizontal axis, the deceleration time constant on a vertical axis, and the operating time on a depth axis. A diagram shown in Fig. Figure 11 illustrates the acceleration time constant on a horizontal axis, the deceleration time constant on a vertical axis, and the energy consumed on a depth axis. The diagram shown in Fig. As illustrated in Figure 10, this is a diagram resulting from the area approximation shown in Fig. Figure 8 illustrates this. The diagram, which is in Fig. As illustrated in Figure 11, this is a diagram resulting from the area approximation shown in Fig. Figure 9 illustrates this.

[0064] A level in Fig. 10 represents an approximation surface AC1 of the operating time and a plane in Fig. Figure 11 represents an approximation surface AC2 of the energy consumption. Based on the approximation surfaces AC1 and AC2, the optimal parameter calculation unit 14 calculates the combination of the acceleration time constants and the deceleration time constants that results in the energy consumption being minimal in the range where the operating time falls within the permissible operating time, as the optimal parameters.

[0065] When calculating the optimal parameters based on the approximation surfaces AC1 and AC2, the optimal parameter calculation unit 14 is enabled to calculate the optimal parameters not from predefined combinations of acceleration and deceleration time constants, but from continuous combinations of acceleration and deceleration time constants. Therefore, the optimal parameter calculation unit 14 is capable of an accurate optimal parameter calculation.

[0066] Each optimal parameter calculation unit 14 calculates a maximum time (maximum value) as the evaluation period for the respective operating times of the drive shafts, each of which is assigned to the optimal parameters, and calculates a drive shaft-specific operating start time that results in minimal energy consumption during the evaluation period. In other words, each optimal parameter calculation unit 14 calculates the drive shaft-specific operating start time such that the energy consumption during the evaluation period, which is the maximum operating time of the respective operating times of the multiple drive shafts, is minimized. Each optimal parameter calculation unit 14 calculates the operating start time after calculating the optimal parameters. The operating start time corresponds to a delay with respect to the time at which the drive shaft begins operation.

[0067] Each optimal parameter calculation unit 14 compares power values ​​for the drive shaft at the beginning and end of operation. If the power at the beginning of operation is lower than the power at the end of operation, the optimal parameter calculation unit 14 calculates a difference between the evaluation period and the operating time as the operating start time. Conversely, if the power at the beginning of operation is greater than or equal to the power at the end of operation, each optimal parameter calculation unit 14 calculates 0 as the operating start time.

[0068] This section provides a description of a process procedure by which the optimal parameter calculation unit 14 calculates the start time of operation. Fig. Figure 12 is a flowchart illustrating the procedure of the process carried out by the optimal parameter calculation unit of the motor control device according to the first embodiment. Fig. Figure 12 is the flowchart illustrating an operating sequence of the optimal parameter calculation unit 14. The optimal parameter calculation unit 14 executes the process that is described in Fig. 12 illustrates, for each synchronous operation instruction, that is included in the set (for each block).

[0069] Optimal parameter calculation unit 14 sets ii, which specifies a ii-th drive shaft (where ii is a natural number), to 1 (step S10). Optimal parameter calculation unit 14 calculates the optimal parameters for the ii-th drive shaft (step S11). Optimal parameter calculation unit 14 calculates the operating time corresponding to the optimal parameters for the ii-th drive shaft (step S12).

[0070] Optimal parameter calculation unit 14 determines whether ii equals the number of drive shafts or not (step S13). If optimal parameter calculation unit 14 determines that ii is not equal to the number of drive shafts (step S13, No), optimal parameter calculation unit 14 sets ii to ii+1 (step S14). Optimal parameter calculation unit 14 then performs the operations of steps S11 to S13.

[0071] The optimal parameter calculation unit 14 repeats the process from step S14 and the processes from steps S11 to S13 until the optimal parameter calculation unit 14 determines that ii is equal to the number of drive shafts.

[0072] If the optimal parameter calculation unit 14 determines that ii is equal to the number of drive shafts (step S13, JA), the optimal parameter calculation unit 14 calculates the maximum operating time of all drive shafts included in the set of synchronous operating commands as the evaluation period (step S15). For example, if the operating command for the spindle and the operating command for the feed shaft are included in the set of synchronous operating commands, and the operating time of the feed shaft is longer than the operating time of the spindle, each optimal parameter calculation unit 14 sets the operating time of the feed shaft as the evaluation period.

[0073] The optimal parameter calculation unit 14 sets ii, which specifies the ii-th drive shaft, to 1 (step S16). The optimal parameter calculation unit 14 determines whether the following is true for the second drive shaft: the power at the beginning of operation <die Leistung am Ende des Betriebs, oder nicht (Schritt S17). Mit anderen Worten bestimmt die Optimalparameterberechnungseinheit 14, für die ii-te Antriebswelle, ob die Leistung zu Beginn des Betriebs geringer ist als die Leistung am Ende des Betriebs, oder nicht.

[0074] If the optimal parameter calculation unit 14 determines for the ii-th drive shaft that the power at the beginning of operation <die Leistung am Ende des Betriebs (Schritt S17, Ja), berechnet die Optimalparameterberechnungseinheit 14 „den Bewertungszeitraum-die Betriebszeit“ als den Betriebsstartzeitpunkt für die ii-te Antriebswelle (Schritt S18).

[0075] If, on the other hand, the optimal parameter calculation unit 14 determines for the ii-th drive shaft that the power at the beginning of operation ≥ the power at the end of operation (step S17, No), the optimal parameter calculation unit 14 calculates 0 as the start time of operation for the ii-th drive shaft (step S19).

[0076] After step S18 or S19, the optimal parameter calculation unit 14 determines whether ii equals the number of drive shafts or not (step S20). If the optimal parameter calculation unit 14 determines that ii is not equal to the number of drive shafts (step S20, No), the optimal parameter calculation unit 14 returns to the process of step S17 and performs the operations of steps S17 and S18 or the operations of steps S17 and S19.

[0077] Optimal parameter calculation unit 14 repeats the process from step S20 and the processes from steps S17 to S19 until optimal parameter calculation unit 14 determines that ii equals the number of drive shafts. If optimal parameter calculation unit 14 determines that ii equals the number of drive shafts (step S20, Yes), optimal parameter calculation unit 14 terminates the calculation process for the start of operation.

[0078] In this way, the optimal parameter calculation unit 14 calculates the optimal parameters and the operating start time for each drive shaft. The optimal parameter calculation unit 14 sends the drive shaft-specific optimal parameters and the drive shaft-specific operating start time, which the optimal parameter calculation unit 14 has calculated, to the motor control unit 15.

[0079] For the synchronous operating commands, the motor control unit 15 generates control signals for the motors 4 based on the optimal parameters and the operating start times calculated by the optimal parameter calculation units 14, thereby causing the drive shafts to be operated as desired.

[0080] For each drive shaft, the motor control unit 15 waits a time equal to the start of operation before issuing a command. In other words, the command start time for each drive shaft is delayed by the motor control unit 15 by the time equal to the start of operation.

[0081] A control method by which the motor control unit 15 controls the motors 4 can be a proportional-integral differential (PID) control or pulse width modulation (PWM) control.

[0082] Fig. Figure 13 is a representation illustrating first exemplary command patterns using optimal parameters calculated by the motor control device according to the first embodiment. Fig. Figure 14 is a representation illustrating initial exemplary power waveforms resulting from the use of the optimal parameters calculated by the motor control device according to the first embodiment. The power waveforms shown in Fig. The 14 illustrations correspond to the command patterns shown in Fig. 13 are illustrated.

[0083] The command patterns and power waveforms that are in the Fig. 13 and Fig. Figure 14 illustrates cases where the operating time of the spindle is shorter than the operating time of the feed shaft and where the power value for the spindle at the beginning of operation is smaller than the power value at the end of operation.

[0084] An upper diagram, which is in Fig. Figure 13 illustrates this, representing time on a horizontal axis and the velocity of the feed shaft on a vertical axis. A lower diagram, shown in Fig. Figure 13 illustrates this, representing time on a horizontal axis and the spindle speed on a vertical axis. An upper diagram, shown in Fig. Figure 14 illustrates this, representing time on a horizontal axis and feed shaft power on a vertical axis. A lower diagram, shown in Fig. Figure 14 illustrates time on a horizontal axis and spindle power on a vertical axis.

[0085] Fig. Figure 13 is the representation in which the command pattern for the feed shaft and the command pattern for the spindle are schematically illustrated, with the optimal parameters set. Fig. Figure 14 is a schematic illustration of the feed shaft power waveform and the spindle power waveform resulting from the setting of the optimal parameters. The optimal parameters in the case of Fig. 13 include an optimal feed shaft acceleration time constant Fcr2, which is an optimal acceleration time constant for the feed shaft, an optimal feed shaft deceleration time constant Fdr2, which is an optimal deceleration time constant for the feed shaft, and an optimal spindle acceleration time constant Mcr2, which is an optimal acceleration time constant for the spindle.

[0086] As in Fig. As illustrated in Figure 13, the command pattern with the set optimal parameters for the feed shaft is such that the feed shaft is to be accelerated, or its speed increased, according to the optimal feed shaft acceleration time constant Fcr2 until it reaches a command speed specified in the machining program 2, and is then driven at this command speed. Subsequently, the feed shaft is to be decelerated and come to a stop according to the optimal feed shaft deceleration time constant Fdr2. The command pattern with the set optimal parameter for the spindle is such that the spindle speed is to be increased according to the optimal spindle acceleration time constant Mcr2.

[0087] Since the command patterns that are in Fig. 13 are illustrated, and the power waveforms show that the operating time of the feed shaft is at its maximum among the operating times of the drive shafts, the optimal parameter calculation units 14 calculate the operating time of the feed shaft as the evaluation period.

[0088] In the case of the feed shaft, the power at the start of operation <die Leistung am Ende des Betriebs. Daher berechnet die Optimalparameterberechnungseinheit 14 „den Bewertungszeitraum-die Betriebszeit“=0 als den Betriebsstartzeitpunkt für die Vorschubwelle.

[0089] In the case of the spindle, the power at the start of operation <die Leistung am Ende des Betriebs. Daher berechnet die Optimalparameterberechnungseinheit 14 für die Spindel einen Betriebsstartzeitpunkt T1, der gleich „dem Bewertungszeitraum-der Betriebszeit“ ist. Mit anderen Worten berechnet die Optimalparameterberechnungseinheit 14 für die Spindel den Betriebsstartzeitpunkt T1, der gleich „der Betriebszeit der Vorschubwelle, bei der es sich um den Bewertungszeitraum handelt, minus der Betriebszeit der Spindel“ ist. Dieser Betriebsstartzeitpunkt T1 entspricht einer Zeit Wt1 zwischen dem Beginn des Betriebs der Vorschubwelle und dem Beginn des Betriebs der Spindel.

[0090] Accordingly, the motor control unit 15, according to the command pattern with the set optimal parameter for the spindle, waits the time Wt1 from the start-up time of the feed shaft before it begins issuing a command to the spindle. As a result, the feed shaft reaches the desired position when the spindle reaches the command speed. In other words, the spindle only needs to reach the command speed once the feed shaft has reached the desired position.

[0091] If the spindle reaches the command speed before the feed shaft reaches the desired position, the spindle rotates unnecessarily before the feed shaft reaches the desired position, leading to an increase in the spindle's energy consumption. The motor control device 10A according to the first embodiment waits the time Wt1 before starting the spindle operation, thus ensuring that the arrival of the feed shaft at the desired position coincides with the spindle reaching the command speed, and consequently preventing the increase in energy consumption.

[0092] As in Fig. Figure 14 illustrates a feed shaft power waveform Fw2, which refers to the power waveform of the feed shaft resulting from the setting of the optimal parameters. This waveform is a collection of power values ​​sampled within the feed shaft's operating time. The optimal parameters for the feed shaft refer to the combination of the optimal feed shaft acceleration time constant Fcr2 and the optimal feed shaft deceleration time constant Fdr2. The feed shaft energy consumption, in this case, is a minimum feed shaft energy consumption Em1.

[0093] A spindle power waveform Mw2, which refers to the spindle's power waveform resulting from the setting of the optimal parameter, is a collection of power values ​​sampled during the spindle's operating time. The optimal parameter for the spindle refers to the optimal spindle acceleration time constant Mcr2, and the spindle's energy consumption in this case is a minimum spindle energy consumption Em2.

[0094] Fig. Figure 15 is a representation illustrating second exemplary command patterns using optimal parameters calculated by the motor control device according to the first embodiment. Fig. Figure 16 is a representation illustrating second exemplary power waveforms resulting from the use of the optimal parameters calculated by the motor control device according to the first embodiment. The power waveforms shown in Fig. The 16 illustrated examples correspond to the command patterns shown in Fig. 15 are illustrated.

[0095] The command patterns and power waveforms that are in the Fig. 15 and Fig. Figure 16 illustrates cases where the operating time of the spindle is shorter than the operating time of the feed shaft and where the power value for the spindle at the beginning of operation is greater than the power value at the end of operation.

[0096] An upper diagram, which is in Fig. Figure 15 illustrates this, representing time on a horizontal axis and the velocity of the feed shaft on a vertical axis. A lower diagram, shown in Fig. Figure 15 illustrates this, representing time on a horizontal axis and the spindle speed on a vertical axis. An upper diagram, shown in Fig. Figure 16 illustrates time on a horizontal axis and feed shaft power on a vertical axis. A lower diagram, shown in Fig. Figure 16 illustrates time on a horizontal axis and spindle power on a vertical axis.

[0097] Fig. Figure 15 is the representation in which the command pattern for the feed shaft and the command pattern for the spindle are schematically illustrated, with the optimal parameters set. Fig. Figure 16 is a schematic illustration of the feed shaft power waveform and the spindle power waveform resulting from the setting of the optimal parameters. The optimal parameters in the case of Fig. 15 include an optimal feed shaft acceleration time constant Fcr3, which is an optimal acceleration time constant for the feed shaft, an optimal feed shaft deceleration time constant Fdr3, which is an optimal deceleration time constant for the feed shaft, and an optimal spindle acceleration time constant Mcr3, which is an optimal acceleration time constant for the spindle.

[0098] As in Fig. As illustrated in Figure 15, the command pattern with the set optimal parameters for the feed shaft is such that the feed shaft is to be accelerated, or its speed increased, according to the optimal feed shaft acceleration time constant Fcr3 until it reaches a command speed specified in the machining program 2, and is then driven at this command speed. Subsequently, the feed shaft is to be decelerated and stopped according to the optimal feed shaft deceleration time constant Fdr3. The command pattern with the set optimal parameter for the spindle is such that the spindle speed is to be increased according to the optimal spindle acceleration time constant Mcr3.

[0099] Since the command patterns that are in Fig. 15 are illustrated, and the power waveforms show that the operating time of the feed shaft is at its maximum among the operating times of the drive shafts, the optimal parameter calculation units 14 calculate the operating time of the feed shaft as the evaluation period.

[0100] In the case of the feed shaft, the power at the start of operation <die Leistung am Ende des Betriebs. Daher berechnet die Optimalparameterberechnungseinheit 14 „den Bewertungszeitraum-die Betriebszeit“=0 als den Betriebsstartzeitpunkt für die Vorschubwelle.

[0101] In the case of the spindle, the power at the beginning of operation is ≥ the power at the end of operation. Therefore, the optimal parameter calculation unit 14 calculates an operating start time T1 for the spindle, which is equal to "the evaluation period - the operating time".

[0102] As in Fig. Figure 16 illustrates a feed shaft power waveform Fw3, which refers to the power waveform of the feed shaft resulting from the setting of the optimal parameters. This waveform is a collection of power values ​​sampled within the feed shaft's operating time. The optimal parameters for the feed shaft refer to the combination of the optimal feed shaft acceleration time constant Fcr3 and the optimal feed shaft deceleration time constant Fdr3. The feed shaft energy consumption, in this case, is a minimum feed shaft energy consumption Em3.

[0103] A spindle power waveform Mw3, which refers to the spindle's power waveform resulting from the setting of the optimal parameter, is a collection of power values ​​sampled during the spindle's operating time. The optimal parameter for the spindle refers to the optimal spindle acceleration time constant Mcr3, and the spindle's energy consumption in this case is a minimum spindle energy consumption Em4.

[0104] Fig. Figure 17 is a flowchart illustrating the procedure of a process performed by the motor control device according to the first embodiment. In the motor control device 10A, the synchronous operation command extraction unit 11 receives the machining program 2 (step S21). The synchronous operation command extraction unit 11 extracts the synchronous operation commands from the machining program 2 (step S22).

[0105] Each operating state calculation unit 12 calculates the operating states that correspond to the synchronous operating command and are specific to the drive shaft included in the synchronous operating command (step S23). Each operating state calculation unit 12 sends the drive shaft-specific operating state table 51, in which the operating states are stored, to the optimal parameter calculation unit 14. Each input unit of the permissible operating time 13 inputs the buffer time for the operating time into the optimal parameter calculation unit 14.

[0106] Each optimal parameter calculation unit 14 calculates the sum of the minimum operating time calculated by the operating state calculation unit 12 and the buffer time as the permissible operating time. For each synchronous operating command, each optimal parameter calculation unit 14 calculates the drive shaft-specific optimal acceleration time constant and the drive shaft-specific optimal deceleration time constant as the optimal parameters based on the operating state table 51 (step S24). Specifically, each optimal parameter calculation unit 14 calculates the drive shaft-specific combination of the acceleration time constants and the deceleration time constants that results in minimal energy consumption in the range where the operating time falls within the permissible operating time, as the combination of the optimal acceleration time constants and the optimal deceleration time constants.Using the drive shaft-specific combination of the optimal acceleration time constants and the optimal deceleration time constants as the optimal parameters, the motor control unit 15 controls the motor 4 (step S25).

[0107] Furthermore, setting an optimal parameter for the entire machining program 2 does not enable reduced energy consumption for an entire process that includes operations other than machining, such as tool changes.

[0108] In contrast, according to the first embodiment, the motor control device 10A extracts the blocks in which the setpoint control for two or more of the synchronously running drive shafts is to be continuously commanded as the set of synchronous operating commands and calculates the optimal parameters for each of the extracted synchronous operating commands. Therefore, the motor control device 10A is capable of setting the parameters that enable a reduction in the required time (cycle time) and minimized energy consumption for operations that do not directly contribute to machining, such as tool changes.

[0109] The motor control device 10A is capable of minimizing the total energy consumption of the tool change operations included in machining program 2 by extracting the tool change operations from machining program 2 and setting optimal parameters for each tool change operation. Furthermore, because the motor control device 10A extracts the tool change operation from machining program 2 and sets the optimal parameters, it reduces the time required to calculate these optimal parameters.

[0110] As described above, according to the first embodiment, the motor control device 10A extracts from the machining program 2 the blocks in which the setpoint control for the multiple drive shafts, which run synchronously, is to be continuously commanded, and extracts the synchronous operating commands contained in the blocks. Furthermore, based on the acceleration time constant and the deceleration time constant, the motor control device 10A calculates the operating time and the energy consumption associated with the machining operation to be performed with the machining program 2. For each of the synchronous operating commands, the motor control device 10A calculates the acceleration time constant and the deceleration time constant that result in the operating time of the drive shaft being within the permissible operating time and the energy consumption being minimal, as the optimal parameters.

[0111] In this way, the motor control device 10A is able to adjust the parameters for operations other than machining, enabling a shorter cycle time and minimized energy consumption. Therefore, the motor control device 10A is able to control the motors 4 through the generated machining program 2, which can reduce the cycle time and minimize energy consumption for operations other than machining, such as tool changes. Second embodiment.

[0112] With reference to the Fig. Sections 18 to 20 then provide a description of a second embodiment. In this second embodiment, optimal parameters are set to ensure that the power values ​​of the feed shafts and the power value of a spindle result in a total value that falls within an acceptable range.

[0113] Fig. Figure 18 is a functional diagram of an engine control device according to the second embodiment. Among the elements in Fig. The 18 illustrated components have components that perform the same functions as the motor control device 10A of the first embodiment, which is described in Fig. As illustrated in Figure 1, the same reference symbols are used and are not described to avoid redundancy.

[0114] The motor control device 10B according to the second embodiment includes, in comparison to the motor control device 10A, the synchronous operating command units B1 to Bn instead of the synchronous operating command units A1 to An. In addition to the components of the synchronous operating command units A1 to An, the synchronous operating command units B1 to Bn have corresponding input units for the permissible power 16. The motor control device 10B is described below as having the synchronous operating command units B1 and B2 as the synchronous operating command units.

[0115] The input units of the permissible power 16 are each connected to the optimal parameter calculation units 14. Each input unit of the permissible power 16 stores the minimum permissible power and the maximum permissible power, which specify the permissible range for power waveforms, and inputs the stored minimum permissible power and the stored maximum permissible power into the optimal parameter calculation unit 14.

[0116] The minimum permissible power refers to the maximum regenerative power of converters (included in the motor control unit 15) used to control the motors 4. The maximum permissible power refers to the maximum supply power of the converters used to control the motors 4. Supply power refers to power in a state where it is supplied to the motor 4, while regenerative power refers to power of the motor 4 in a state where it flows as regenerative energy to a power supply side. The maximum regenerative power and the maximum supply power of the converters are limits that correspond to the permissible range. The permissible power input units 16 input the minimum permissible power and the maximum permissible power into the optimal parameter calculation units 14.

[0117] Each of the operating state calculation units 12 according to the second embodiment calculates drive shaft-specific instantaneous power values ​​based on an acceleration time constant and a deceleration time constant for the drive shaft. These instantaneous power values ​​(power consumption values) of the drive shaft are intended to be power values ​​(power consumption values) of the drive shaft at times during the operation of the drive shaft. Each operating state calculation unit 12 calculates, for each time point within the operating time, the sum of the instantaneous power value(s) of the feed shaft(s) and the instantaneous power value of the spindle, that is, the sum of the power values ​​(hereinafter referred to as the total power value).

[0118] Each of the optimal parameter calculation units 14 of the motor control device 10B performs a subsequent process in addition to the process performed by the optimal parameter calculation unit 14 of the motor control device 10A. In other words, each optimal parameter calculation unit 14 of the motor control device 10B calculates, for a synchronous operating command, an acceleration time constant, a deceleration time constant, and an operating start time that result in the operating time being within a permissible operating time, with a minimum total power value being greater than or equal to the minimum permissible power of the range, a maximum total power value being less than or equal to the maximum permissible power of the range, and a total drive shaft energy consumption being minimal.

[0119] If, for the drive shafts at a given time, a minimum total power value of the total power values ​​is less than the minimum permissible power, or if a maximum total power value of the total power values ​​is greater than the maximum permissible power, the optimal parameter calculation units 14 each change at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant.In this way, each optimal parameter calculation unit 14 calculates the acceleration time constant, the deceleration time constant, and the start-up time that ensure the operating time is within the permissible operating time, the minimum total power value is greater than or equal to the minimum permissible power of the range, the maximum total power value is less than or equal to the maximum permissible power of the range, and the total energy consumption of the drive shafts is minimized. In other words, each optimal parameter calculation unit 14 calculates the acceleration time constant, the deceleration time constant, and the start-up time that ensure the operating time is within the permissible operating time and the total power values ​​fall within the permissible range.

[0120] As described above, each optimal parameter calculation unit 14 modifies at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant to satisfy the permissible operating time, the minimum permissible power, and the maximum permissible power. Each optimal parameter calculation unit 14 modifies at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant after calculating the optimal parameters and the operating start time.

[0121] This section provides a description of command patterns using optimal parameters calculated by the optimal parameter calculation units 14, taking into account the range for total power values, and power waveforms resulting from the use of the optimal parameters.

[0122] Fig. Figure 19 is a representation illustrating initial exemplary power waveforms resulting from the use of optimal parameters calculated by the engine control unit according to the second embodiment, taking into account the range for overall power values. An upper diagram, shown in Fig. Figure 19 illustrates this, representing time on a horizontal axis and feed shaft power on a vertical axis. A middle diagram, shown in Fig. Figure 19 illustrates time on a horizontal axis and spindle power on a vertical axis. A lower diagram, shown in Fig. Figure 19 illustrates time on a horizontal axis and the maximum permissible power. Fig. Figure 19 illustrates the power waveforms for a case in which the spindle accelerates. The power waveforms shown in Fig. The 19 illustrated above correspond to the command patterns shown in Fig. 13 are illustrated.

[0123] The optimal parameter calculation units 14 calculate the optimal parameters in the same way as in the first embodiment. The instruction patterns that are in Fig. Figure 13 illustrates the exemplary optimal parameters that are calculated by the optimal parameter calculation units 14.

[0124] Furthermore, the optimal parameter calculation units 14 calculate the power waveforms of the feed shaft and the spindle within the operating time in the same way as in the first embodiment. In other words, the optimal parameter calculation units 14 calculate instantaneous power values ​​based on the acceleration time constants and the deceleration time constants for the drive shafts. These instantaneous power values ​​(power consumption values) of the drive shafts at specific times are used to calculate the power waveforms of the feed shaft and the spindle. The waveforms that are calculated in Fig. Figure 14 illustrates the exemplary power waveforms of the feed shaft and the spindle, which were calculated by the optimal parameter calculation units 14.

[0125] The optimal parameter calculation units 14 calculate a total power value for each time within the operating time, which is the sum of the power value of the feed shaft and the power value of the spindle, that is, the sum of and calculation of a power waveform that corresponds to the total power values. A total power waveform Tw1, which in Fig. Figure 19 illustrates the power waveform, which results from the addition of each power value of the spindle power waveform Mw1 and each power value of the feed shaft power waveform Fw1.

[0126] Fig. Figure 20 is a representation illustrating two exemplary power waveforms resulting from the use of optimal parameters calculated by the engine control unit according to the second embodiment, taking into account the range for overall power values. An upper diagram, shown in Fig. Figure 20 illustrates this, representing time on a horizontal axis and feed shaft power on a vertical axis. A middle diagram, shown in Fig. Figure 20 illustrates this, representing time on a horizontal axis and spindle power on a vertical axis. A lower diagram, shown in Fig. Figure 20 illustrates time on a horizontal axis and the maximum permissible power. Fig. Figure 20 illustrates the power waveforms for a case where the spindle is decelerated. The power waveforms shown in Fig. The 20 illustrated examples correspond to the command patterns shown in Fig. 15 are illustrated.

[0127] The optimal parameter calculation units 14 calculate the optimal parameters in the same way as in the first embodiment. The instruction patterns that are in Fig. Figure 15 illustrates the exemplary optimal parameters that are calculated by the optimal parameter calculation units 14.

[0128] Furthermore, the optimal parameter calculation units 14 calculate the power waveforms of the feed shaft and the spindle within the operating time in the same way as in the first embodiment. In other words, the optimal parameter calculation units 14 calculate instantaneous power values ​​based on the acceleration time constants and the deceleration time constants for the drive shafts. These instantaneous power values ​​(power consumption values) of the drive shafts at specific times are used to calculate the power waveforms of the feed shaft and the spindle. The waveforms that are calculated in Fig. Figure 16 illustrates the exemplary power waveforms of the feed shaft and the spindle, which were calculated by the optimal parameter calculation units 14.

[0129] The optimal parameter calculation units 14 calculate a total power value for each time within the operating time, which is the sum of the power value of the feed shaft and the power value of the spindle, that is, the sum of and calculation of a power waveform that corresponds to the total power values. A total power waveform Tw2, which in Fig. Figure 20 illustrates the power waveform resulting from the addition of each power value of the spindle power waveform Mw2 and each power value of the feed shaft power waveform Fw2.

[0130] The optimal parameter calculation units 14 determine whether a minimum total power value of the total power values ​​within the operating time is less than the minimum permissible power or not. Furthermore, the optimal parameter calculation units 14 determine whether a maximum total power value of the total power values ​​within the operating time is greater than the maximum permissible power or not. In other words, the optimal parameter calculation units 14 determine whether the power values ​​of each of the total power waveforms Tw1 and Tw2 are greater than or equal to the minimum permissible power and less than or equal to the maximum permissible power.

[0131] If the minimum total power output of the feed shaft and spindle during operation is less than the minimum permissible power, the optimal parameter calculation units 14 each modify at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant. In this case, the optimal parameter calculation units 14 modify at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant so that the total power output during operation falls within the permissible range.

[0132] If the maximum total power output within the operating time for the feed shaft and the spindle exceeds the minimum permissible power output, the optimal parameter calculation units 14 each modify at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant. In this case, the optimal parameter calculation units 14 each modify at least one of the operating start time, the optimal acceleration time constant, or the optimal deceleration time constant so that the total power output within the operating time falls within the permissible range.

[0133] As described above, the motor control device 10B, according to the second embodiment, sets the optimal parameters such that the power value(s) of the feed shaft(s) and the power value of the spindle together result in a power value that falls within the permissible range. Therefore, the motor control device 10B is capable of calculating the optimal parameters, ensuring that the maximum regenerative power and the maximum power supply to the converters are not exceeded. Third embodiment.

[0134] With reference to the Fig. Sections 21 to 22 next provide a description of a third embodiment. In the third embodiment, the motor control device 10A or 10B is applied to a machining system that uses the machining program 2 to machine a workpiece.

[0135] Fig. Figure 21 is a functional diagram of the machining system according to the third embodiment. The machining system 1 includes a CAM system 30 with an input model 31 for computer-aided design (CAD), the machining program 2, the motor control device 10A or 10B, and the machining attachment 3. A description of the machining system 1, to which the motor control device 10A is applied, is provided here.

[0136] The CAM system 30 creates the machining program 2 using the CAD model 31, which controls the machining device 3, and enters the created machining program 2 into the motor control device 10A.

[0137] The machining device 3 includes a spindle motor 21, a spindle 22, a tool 23, a feed shaft motor 24, the workpiece 25, a platform 26, a workpiece feed shaft 27, feed shaft motors 28 and tool feed shafts 29. The spindle motor 21 and the feed shaft motors 24 and 28 are connected to the motor control device 10A and rotate according to control signals sent by the motor control device 10A.

[0138] The spindle 22 is attached to the spindle motor 21, and the tool 23 is attached to the spindle 22. The spindle motor 21 rotates the tool 23, with the spindle 22 serving as a rotating shaft.

[0139] The rod-shaped tool feed shafts 29 are each attached to the feed shaft motors 28, and the spindle 22 is coupled to the tool feed shafts 29. The feed shaft motors 28 rotate the tool feed shafts 29, thereby axially moving the spindle 22.

[0140] For example, the number of feed shaft motors 28 of the machining device 3 is three, and the number of tool feed shafts 29 is three. In this case, the feed shaft motors 28 include an X-axis motor that moves the spindle 22 along an X-axis, a Y-axis motor that moves the spindle 22 along a Y-axis, and a Z-axis motor that moves the spindle 22 along a Z-axis. The tool feed shafts 29 include a feed shaft extending in an X-axis direction and connected to the X-axis motor, a feed shaft extending in a Y-axis direction and connected to the Y-axis motor, and a feed shaft extending in a Z-axis direction and connected to the Z-axis motor. Therefore, the spindle 22 is moved along the X-, Y-, and Z-axes by the three feed shaft motors 28 and the three tool feed shafts 29.

[0141] The rod-shaped workpiece feed shaft 27 is attached to the feed shaft motor 24, and the platform 26 is coupled to the workpiece feed shaft 27. The feed shaft motor 24 rotates the workpiece feed shaft 27, thereby moving the platform 26 axially along the workpiece feed shaft 27. There is at least one workpiece feed shaft 27 extending along the X-axis, Y-axis, Z-axis, A-axis, B-axis, and C-axis. The number of feed shaft motor(s) 24 and workpiece feed shaft(s) 27 is the same. The workpiece 25, which is the workpiece to be machined, is placed on the platform 26.

[0142] The feed shaft motors 28 move the tool 23 via the tool feed shafts 29 and the spindle 22 to a machining position, and the feed shaft motor 24 moves the workpiece 25 via the workpiece feed shaft 27 and the platform 26 to the machining position. The spindle motor 21 rotates the tool 23 at the machining position via the spindle 22. In this way, the workpiece 25 is machined by the tool 23.

[0143] If a tool change is to follow the machining of the workpiece 25, the feed shaft motors 28 move the tool 23 to a tool change position, while the spindle motor 21 stops the rotation of the tool 23. Commands for the spindle motor 21 and the feed shaft motors 28 are synchronous operating commands in this case.

[0144] If the workpiece 25 is to be machined after the tool 23 has been changed, the feed shaft motors 28 move the tool 23 to a machining position, while the spindle motor 21 begins to rotate the tool 23. Commands for the spindle motor 21 and the feed shaft motors 28 are synchronous operating commands in this case.

[0145] The motor control device 10A, which includes the numerical control device, receives the machining program 2 from the CAM system 30. The motor control device 10A generates a set of control signals to move the tool 23 relative to the workpiece 25 so that the workpiece 25 is machined. The motor control device 10A generates the set of control signals in the manner described in the first embodiment. The set of control signals includes the control signal for the spindle motor 21 and the control signal(s) for the feed shaft motor(s) 24.

[0146] Fig. Figure 22 is a flowchart illustrating the procedure of a process performed by the machining system according to the third embodiment. The CAM system 30 of machining system 1 receives the CAD model 31 (step S31). Using the CAD model 31, the CAM system 30 creates the machining program 2 (step S32).

[0147] For synchronous operating commands where setpoint control is required, the motor control unit 10A calculates optimal parameters based on machining program 2 and permissible operating times (step S33). The motor control unit 10A calculates combinations of optimal acceleration time constants and optimal deceleration time constants, each of which results in minimal energy consumption within the permissible operating time.

[0148] The motor control device 10A generates control signals using the optimal parameters and controls the motors 4 using the control signals (step S34).

[0149] Since the motor control device 10A is applied to the machining system 1, the machining system 1 according to the third embodiment, as described above, is capable of setting parameters that allow a shorter cycle time and minimized energy consumption for an operation other than machining as in the first embodiment.

[0150] This section provides a description of the hardware configuration of each of the motor control devices 10A and 10B. Each of the motor control devices 10A and 10B is implemented with a processing circuit. The processing circuit may include a memory and a processor that executes programs stored in the memory, or it may be dedicated hardware, such as dedicated circuits. The processing circuit is also referred to as the control circuit.

[0151] Fig. Figure 23 is a diagram illustrating a configuration example of a processing circuit implemented with a processor and memory as the processing circuit of the motor control device, according to each of the first to third embodiments. Since the motor control devices 10A and 10B have the same hardware configuration, the hardware configuration of motor control device 10A is described here.

[0152] The processing circuit 90, which is in Fig. Figure 23 illustrates a control circuit and includes the processor 91 and the memory 92. For the processing circuit 90, which includes the processor 91 and the memory 92, the functions of the processing circuit 90 are implemented using software, firmware, or a combination of both. The software or firmware is described as programs and is stored in the memory 92. In the processing circuit 90, the processor 91 reads the programs stored in the memory 92 and executes them to implement the functions. This means that the memory 92 in the processing circuit 90 is used to store the programs that lead to the execution of the operations of the motor control device 10A. These programs can be referred to as the programs that cause the functions implemented by the processing circuit 90 to be carried out by the motor control device 10A.These programs can be stored and provided on a storage medium or can be provided by another means, such as a communication medium. The programs can also be referred to as programs that cause the motor control device 10A to carry out the motor control process.

[0153] Examples of processor 91 include a central processing unit (CPU), a processing unit, an arithmetic unit, a microprocessor, a microcomputer, and a digital signal processor (DSP). Processor 91 is found in personal computers (PCs) or programmable logic controllers (PLCs). PLCs are also known as sequencers.

[0154] Examples, each corresponding to Memory 92, include non-volatile and volatile semiconductor memories, such as random-access memory (RAM), read-only memory (ROM), flash memory, erasable programmable ROM (EPROM) and electrically programmable EPROM (EEPROM) (registered trademark), magnetic disk, flexible disk, optical disk, compact disk, mini disk and digital versatile disk (DVD).

[0155] Fig. Figure 24 is a representation illustrating an example of a processing circuit configured as dedicated hardware to serve as the processing circuit of the motor control device, according to each of the first to third embodiments. Examples corresponding to processing circuit 93, which is shown in Fig.Figure 24 illustrates that the processing circuit includes a single circuit, a compound circuit, a programmed processor, a programmed parallel processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or combinations thereof. The processing circuit 93 can be implemented partly by dedicated hardware and partly by software or firmware. By including the dedicated hardware, the software, the firmware, or a combination thereof, the processing circuit 93 is capable of implementing the aforementioned functions.

[0156] The configurations described above, illustrated in the embodiments, are for illustrative purposes only and can be combined with other, generally known techniques and partially omitted or modified without deviating from the core principle. The embodiments can be combined with one another. List of reference symbols

[0157] 1 Machining system; 2 Machining program; 3 Machining device; 4 Motor; 10A, 10B Motor control device; 11 Extraction unit for synchronous operating commands; 12 Operating state calculation unit; 13 Input unit for permissible operating time; 14 Optimal parameter calculation unit; 15 Motor control unit; 16 Input unit for permissible power; 21 Spindle motor; 22 Spindle; 23 Tool; 24, 28 Feed shaft motor; 25 Workpiece; 26 Platform; 27 Workpiece feed shaft; 29 Tool feed shaft; 30 CAM system; 31 CAD model; 51 Operating state table; 90, 93 Processing circuit; 91 Processor; 92 Memory; A1 to An Synchronous operating command units; AC1, AC2 Approach surface; At1 Permissible operating time; B1 to Bn Synchronous operating command units; Em1, Em3 minimum feed shaft energy consumption; Em2, Em4 minimum spindle energy consumption; Fc1 feed shaft acceleration time constant; Fcr2, Fcr3 optimal feed shaft acceleration time constant;Fd1 Feed shaft deceleration time constant; Fdr2, Fdr3 Optimal feed shaft deceleration time constant; Fe1 Feed shaft energy consumption; Ft1 Feed shaft operating time; Fw1 to Fw3 Feed shaft power waveforms; Mc1 Spindle acceleration time constant; Mcr2, Mcr3 Optimal spindle acceleration time constant; Me1 Spindle energy consumption; Mt1 Spindle operating time; Mw1 to Mw3 Spindle power waveforms; T1 Operating start time; Tw1, Tw2 Total power waveform; Wt1 Time; c1 Acceleration time constant; c2, c4 White dot; c3, c5 Black dot; c6 Diamond-shaped dot; d1 Deceleration time constant.; QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] Japanese Disclosure Document No. 2010-240800

[0004]

Claims

[1] A motor control device for generating a control signal for a motor that drives the drive shaft based on an acceleration time constant that defines an acceleration time of a drive shaft and a deceleration time constant that defines a deceleration time of the drive shaft, the motor control device comprising: a synchronous operation command extraction unit for extracting blocks from a machining program in which command control for a plurality of the drive shafts that run synchronously is to be continuously commanded, and for extracting synchronous operation commands included in the blocks; an operating state calculation unit for calculating an operating time and a consumption energy associated with the machining to be performed with the machining program based on the acceleration time constant and the deceleration time constant; an optimal parameter calculation unit for calculating, for each of the synchronous operation commands, the acceleration time constant and the deceleration time constant that result in the operation time of the drive shaft being within a permissible operation time and the consumption energy being minimal, as optimal parameters, wherein the permissible operation time represents a permissible time for operation; and an engine control unit for generating a control signal for the engine based on the optimal parameters. [2] Engine control device according to claim 1, wherein after calculating the optimal parameters, the optimal parameter calculation unit calculates a drive shaft-specific operation start time that results in the consumption energy being minimal during an evaluation period, wherein the evaluation period is a maximum operating time of a plurality of the operating times of the plurality of drive shafts, and the engine control unit generates a control signal for the engine based on the optimal parameters and the operation start time. [3] Engine control device according to claim 2, wherein the operating state calculation unit calculates, based on the acceleration time constant and the deceleration time constant, an instantaneous power value to be a power value at each of the times during the operation of the drive shaft, and calculates a total power value that is a sum of a plurality of the instantaneous power values ​​of the plurality of drive shafts at each of the times, and after calculating the optimal parameters and the operation start time, the optimal parameter calculation unit changes at least one of the optimal parameters or the operation start time by causing a minimum total power value and a maximum total power value of a plurality of the total power values ​​to fall within an allowable range for the total power value and causing the consumption energy to be minimal. [4] Engine control device according to claim 3, wherein the maximum regenerative power and maximum supply power of converters to be used to control the motor are limits corresponding to the permissible range. [5] The engine control device according to any one of claims 1 to 4, wherein the optimal parameter calculation unit generates, for each of the plurality of drive shafts, discrete distributions having the operation time and the consumption energy corresponding to the acceleration time constant and the deceleration time constant as variables, and applies a surface approximation to the discrete distributions, obtaining an approximate surface expressing one of the operation time and the consumption energy as a continuous function of the other of the operation time and the consumption energy corresponding to the acceleration time constant and the deceleration time constant, and calculates the optimal parameters based on the approximate surface. [6] Engine control device according to one of claims 1 to 5, wherein the plurality of drive shafts includes a spindle used in rotating a tool and a tool feed shaft used in moving the tool, and the synchronous operation commands include commands that use the spindle and the tool feed shaft for a tool change. [7] The motor control device according to claim 6, wherein the blocks extracted from the machining program by the synchronous operation command extraction unit include at least one of a first movement block for moving from a machining end position where machining ends before the tool change to a tool change position where the tool change is performed, or a second movement block for moving from a tool change end position where the tool change ends to a machining start position where machining is performed next after the tool change. [8] Processing system comprising: the engine control device according to one of claims 1 to 7; and a processing device containing the motor to be controlled by the motor control device. [9] A motor control method for a motor control device for generating a control signal for a motor that drives the drive shaft based on an acceleration time constant defining an acceleration time of a drive shaft and a deceleration time constant defining a deceleration time of the drive shaft, the motor control method comprising: a synchronous operation command extraction step of the motor control device that extracts, from a machining program, blocks in which target control for a plurality of the drive shafts that run synchronously is to be continuously commanded, and extracts synchronous operation commands included in the blocks; a motor control device operating state calculation step that calculates an operating time and a consumption energy associated with the machining to be performed with the machining program based on the acceleration time constant and the deceleration time constant; an optimal parameter calculation step of the motor control device, which calculates, for each of the synchronous operation commands, the acceleration time constant and the deceleration time constant that result in the drive shaft operating time being within a permissible operating time and the consumption energy being minimal, as optimal parameters, wherein the permissible operating time represents a permissible time for operation; and a motor control step of the motor control device that generates a control signal for the motor based on the optimal parameters. [10] A machining method for a machining system for generating a control signal for a motor that drives the drive shaft based on an acceleration time constant that defines an acceleration time of a drive shaft and a deceleration time constant that defines a deceleration time of the drive shaft, and for performing machining, the machining system including a motor control device and a machining device including the motor to be controlled by the motor control device, the machining method comprising: a synchronous operation command extraction step of the motor control device that extracts, from a machining program, blocks in which target control for a plurality of the drive shafts that run synchronously is to be continuously commanded, and extracts synchronous operation commands included in the blocks; a motor control device operating state calculation step that calculates an operating time and a consumption energy associated with the machining to be performed with the machining program based on the acceleration time constant and the deceleration time constant; an optimal parameter calculation step of the motor control device, which calculates, for each of the synchronous operation commands, the acceleration time constant and the deceleration time constant that result in the drive shaft operating time being within a permissible operating time and the consumption energy being minimal, as optimal parameters, wherein the permissible operating time represents a permissible time for operation; a motor control step of the motor control device, which generates a control signal for the motor based on the optimal parameters; and a machining step of the machining device that performs the machining by operating the motor according to the control signal.

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