Motor selection device and motor selection program

Abstract

To provide an electric motor selection device and an electric motor selection program for facilitating the selection of a plurality of electric motors constituting a multi-axis machine.SOLUTION: An electric motor selection device 1 includes a multi-axis machine model holding part 20 for holding information of a plurality of multi-axis machine models, a model selection input part 31 for selecting one multi-axis machine model, a mechanism specification input part 32 for receiving an input of mechanism specifications, an operation condition input part 33 for receiving an input of an operation condition, a calculation model creation part 55 for creating a calculation model on the basis of the multi-axis machine model and the mechanism specifications, a calculation part 50 for calculating a load pattern of a drive part on the basis of the calculation model and the operation condition, and a selection part 60. The selection part retrieves electric motors having characteristic information suitable for the load pattern with reference to an electric motor database 40, selects a plurality of electric motors for respectively driving a plurality of drive parts of the multi-axis machine models, and generates machine type specification information of the selected electric motors as a selection result.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This invention relates to an apparatus and a computer program for selecting an electric motor.

Background Art

[0002] Industrial robots used in semiconductor manufacturing equipment, machine tools, etc. may include a multi-axis machine having a plurality of drive shafts. The multi-axis machine includes a plurality of drive shafts and electric motors that drive them respectively. An example of a multi-axis machine is an articulated robot. The articulated robot has drive shafts at joint portions that rotatably connect a plurality of arms (links), and further has an electric motor that drives the drive shafts. When selecting an electric motor, the motion pattern and load pattern at the load end of the multi-axis machine are considered.

[0003] Prior art related to the selection of electric motors is described in, for example, Patent Documents 1 to 4.

[0004] Patent Document 1 discloses an apparatus for selecting the capacity of electric motors that drive a plurality of drive shafts included in a multi-axis system. The capacity of an electric motor is the output of the electric motor, which is given by the product of torque and angular velocity and is proportional to the product of torque and rotational speed. Patent Document 2 discloses an apparatus for selecting a servo motor and its peripheral devices in a multi-axis drive system. Patent Document 3 discloses a simulator for simulating the operation of a multi-axis machine device and describes simulations for selecting the capacity of an electric motor. Patent Document 4 discloses an apparatus for selecting an electric motor control device based on usage conditions, constructs a subsystem including a plurality of mechanical elements, and realizes the selection of an electric motor control device that conforms to the operation pattern of a multi-axis machine system.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

[0006] For example, a robot equipped with a multi-joint arm, each with a drive axis at its joints, has multiple arms and multiple electric motors corresponding to each of the multiple drive axes. The load pattern of a certain electric motor depends on the mass and motion patterns of the arms and electric motors located closer to the machine end. More specifically, the load pattern of the electric motor closest to the machine end (hereinafter referred to as the "machine end electric motor" in this section) depends on the load at the machine end (e.g., the mass and moment of inertia of the workpiece) and the motion pattern at the machine end. The load pattern of the electric motor next closest to the machine end includes the influence of the arms it drives, the machine end electric motor, and the load at the machine end. Thus, selecting electric motors in a multi-axis machine driven by multiple electric motors involves repeatedly calculating the load pattern and selecting electric motors based on that calculation for each drive axis, which requires a great deal of time and effort.

[0007] Furthermore, changing some of the electric motors, altering mechanical specifications such as arm length, or changing the motion conditions (load or motion pattern) at the machine end will cause the operating pattern and load pattern of each electric motor to change accordingly. Consequently, virtually all electric motors need to be re-selected. This makes flexible design changes difficult and makes it challenging to adapt to changes in operating conditions.

[0008] Patent documents 1 to 3 select capacity based solely on input information such as multi-axis machine models and mechanism specifications entered by the user. Therefore, they are suitable for verification after the design of the multi-axis machine is completed, including the selection of the electric motor. In other words, they are suitable for determining whether the selected electric motor satisfies the desired operating pattern and load pattern. On the other hand, they are not necessarily suitable for selecting electric motors during the construction phase of the multi-axis machine (the robot design phase or the operating condition setting phase). That is, the user will have to select an appropriate electric motor by repeatedly trying out capacity calculations after making a provisional selection. Therefore, selecting an electric motor still requires a great deal of time and effort.

[0009] Patent Document 4 describes the influence of the selected motor model on other drive shafts. However, it does not mention the influence of physical models such as mass, shape, and center of gravity on other drive shafts, i.e., the calculation of the variation in load patterns, and the specific technical details remain unclear.

[0010] Therefore, one embodiment of this invention provides an electric motor selection device and an electric motor selection program that facilitate the selection of multiple electric motors constituting a multi-axis machine. [Means for solving the problem]

[0011] 1. A multi-axis machine model holding unit that holds information on multiple multi-axis machine models, each representing the configuration of multiple multi-axis machines, each comprising multiple drive units and multiple electric motors that drive each of the multiple drive units, A model selection input unit that accepts a selection input for selecting one multi-axis machine model from the aforementioned multiple multi-axis machine models, For the multi-axis machine model selected by the aforementioned selection input, a mechanism specification input unit accepts input of mechanism specifications, For the multi-axis machine model selected by the aforementioned selection input, there is an operating condition input unit that accepts input of operating conditions, A calculation model creation unit creates a calculation model based on the multi-axis machine model selected by the selection input and the mechanism specifications received by the mechanism specifications input unit, A calculation unit calculates the load pattern of the drive unit based on the calculation model created by the calculation model creation unit and the operating conditions received by the operating condition input unit, The system includes a selection unit that refers to an electric motor database storing model identification information, physical model information, and characteristic information for multiple electric motors, searches for electric motors having characteristic information that matches the load pattern calculated by the calculation unit, selects multiple electric motors to drive each of the multiple drive units of the selected multi-axis machine model, and generates the model identification information of the selected electric motors as a selection result. The selection unit selects a plurality of electric motors to drive each of the plurality of drive units by sequentially selecting electric motors from the electric motor database to drive the drive units on the machine end side of the multi-axis machine model, The calculation model creation unit is a motor selection device that, when the selection unit selects a motor, obtains the physical model of the motor from the motor database and supplements it with the calculation model.

[0012] According to this configuration, by selecting a multi-axis machine model, inputting its mechanism specifications, and further inputting the motion conditions of the multi-axis machine model, multiple electric motors suitable for driving each of the multiple drive units of the multi-axis machine are selected, and model identification information for these motors is generated as a selection result. This allows multiple electric motors to be selected at once. Moreover, since model identification information is generated, unlike Patent Document 1, etc., where capacity is selected, the user does not need to select a model suitable for the capacity.

[0013] To select an appropriate electric motor, a calculation model is created based on the multi-axis machine model and its mechanical specifications. Based on this calculation model and the operating conditions, the load pattern of the drive unit is calculated. By searching the electric motor database for motors with characteristic information that match this load pattern, the electric motor corresponding to each drive unit is selected.

[0014] The selection of electric motors is performed sequentially from the machine ends of the multi-axis machine model. Once a motor is selected, its physical model is incorporated into the computational model. Therefore, when the next motor is selected, the physical model of the motor driving the drive unit closer to the machine end than the drive unit driven by the selected motor is incorporated into the computational model. As a result, since the computational model takes into account the physical models of the motors incorporated into the multi-axis machine, the load pattern of the drive unit for which the motor is being selected can be accurately determined. Since a motor with characteristic information that matches this accurately determined load pattern is selected, appropriate motor selection becomes possible.

[0015] In this way, by sequentially selecting motors and supplementing the computational model with the physical models of the motors, motors that match the accurate load pattern reflecting the motor's influence are selected sequentially, allowing for the selection of multiple motors that match the mechanism specifications and operating conditions at once. In other words, since there is no need to repeat the selection process many times, multiple motors constituting a multi-axis machine can be selected in a short time with little effort.

[0016] A more specific example of the process is as follows:

[0017] When the selection unit selects an nth motor to drive the nth drive unit (where n is a natural number of 2 or more and less than or equal to the number of drive units in the multi-axis machine model), which is one of the plurality of drive units, the calculation model creation unit refers to the motor database and updates the calculation model by supplementing it with the physical model of the selected nth motor. Based on the updated calculation model, the calculation unit calculates the load pattern of the (n-1)th drive unit, which is the next closest to the machine end after the nth drive unit. Based on the load pattern of the (n-1)th drive unit calculated by the calculation unit, the selection unit selects an (n-1)th motor to drive the (n-1)th drive unit from the motor database.

[0018] 2. The calculation unit calculates the driving pattern of the driving unit based on the calculation model created by the calculation model creation unit and the driving conditions received by the driving condition input unit, and calculates the load pattern of the driving unit using the driving pattern. The selection unit selects an electric motor that matches the driving pattern and load pattern calculated by the calculation unit from the electric motor database. The electric motor selection device according to claim 1.

[0019] When the driving pattern of the driving unit is input as the driving condition, the input driving pattern can be used as it is. When the driving condition is other conditions, for example, the movement pattern of the machine end, etc., it is necessary to calculate the driving pattern of each driving unit. Then, based on the driving pattern and the calculation model, the load pattern can be calculated. When selecting an electric motor, an electric motor that matches the driving pattern and load pattern is selected. The selection unit may refer to an electric motor database that stores characteristic information for multiple electric motors, including model identification information, physical model information, and torque-speed characteristic data representing the output torque characteristics with respect to the rotational speed of each electric motor. Based on the operating pattern and load pattern calculated by the calculation unit, the selection unit identifies the operating speed range and load torque in that operating speed range for each drive unit and determines the capacity conditions required in that operating speed range. By referring to the torque-speed characteristic data included in the characteristic information stored in the electric motor database, the selection unit searches for an electric motor having torque-speed characteristics that satisfy the capacity conditions in the operating speed range, thereby searching for an electric motor having characteristic information that matches the operating pattern and load pattern calculated by the calculation unit, and select multiple electric motors to drive each of the multiple drive units of the selected multi-axis machine model, and generate the model identification information for the selected electric motors as a selection result.

[0020] 3. The selection unit selects an electric motor that matches the load pattern calculated by the calculation unit from the electric motor database according to a predetermined priority condition. The electric motor selection device according to claim 1 or 2. (More preferably, operating patterns and load patterns)

[0021] With this configuration, by appropriately setting the priority conditions, even when multiple electric motors match the load pattern, an appropriate single model of electric motor can be selected.

[0022] 4. The predetermined priority condition is a condition where the smaller the size, the higher the priority order. The electric motor selection device according to claim 3.

[0023] With this configuration, it is possible to select a single model of electric motor with the smallest size that matches the load pattern.

[0024] The size may be the mounting angle dimension or other dimensions, or may be the mass.

[0025] ​ 5. An electric motor selection device according to any one of items 1 to 4, comprising a selection result display unit that displays the model identification information of the electric motor selected by the selection unit.

[0026] This configuration allows the user to be notified of the selection results by displaying model identification information. Since the specific model of the electric motor can be identified, the user can use that information directly to design and manufacture multi-axis machinery.

[0027] 6. A selection result storage unit that stores the selection results of multiple electric motors selected by the selection unit, The motor selection device according to any one of claims 1 to 5, further comprising: a determination unit that determines whether the selection result stored in the selection result storage unit is suitable for a new input to at least one of the mechanism specifications input unit and the operating condition input unit.

[0028] This configuration allows for the determination of whether a selected motor remains suitable after changing at least one of the machine specifications or operating conditions. This enables the design of multi-axis machinery while confirming motor suitability by changing the mechanism specifications or operating conditions.

[0029] 7. The calculation model creation unit calculates a new calculation model in which the physical model of the electric motor corresponding to the selection result stored in the selection result storage unit is supplemented with the multi-axis machine model, based on the new input to at least one of the mechanism specifications input unit and the operating condition input unit. The calculation unit calculates the load pattern of the drive unit based on the newly calculated calculation model. (More preferably, operating patterns and load patterns) We will perform a new calculation, The determination unit determines the newly calculated load pattern (More preferably, operating patterns and load patterns) The motor selection device according to item 6, which performs the determination using the above method.

[0030] In this configuration, a new calculation model is generated in response to changes in at least one of the mechanism specifications and operating conditions. The calculation model is complemented by the physical model of the selected motor. Therefore, by using this calculation model, the load pattern of the drive unit in response to the changes can be accurately calculated, and based on this accurate load pattern, the suitability / unsuitability of the selected motor can be appropriately determined.

[0031] 8. Includes a selection modification input unit that receives a selection modification command that commands a modification to the selection of at least one of the multiple electric motors selected by the selection unit, The selection unit calculates the load pattern that the calculation unit calculates based on the selection correction command received by the selection correction input unit. (More preferably, operating patterns and load patterns) A motor selection device according to any one of items 1 to 7, which re-selects a motor that conforms to the above from the motor database.

[0032] This configuration allows for modifications to the selection results and re-selection of the motors. For example, when changing at least one of the mechanism specifications and operating conditions, the selection results for some motors may be maintained while the remaining motors are re-selected. More specifically, when the above determination is made after changing the mechanism specifications or operating conditions, some motors may be determined to be suitable, while the remaining motors may be determined to be unsuitable. In such cases, the selection of at least one motor determined to be suitable can be maintained, and the remaining motors can be re-selected. By providing such a re-selection function, it becomes easier for users to obtain the desired selection results, and it is possible to support the flexible design of multi-axis machines.

[0033] The selection modification input unit may accept a selection modification command that maintains the selection of at least one of the multiple electric motors selected by the selection unit and excludes at least one of the multiple electric motors from the selection candidates. This ensures that a different selection result can be obtained for the electric motors subject to reselection.

[0034] 9. The calculation model creation unit creates a new calculation model by supplementing the multi-axis machine model with the physical model of the motor that is not subject to modification and the physical model of the motor that has been re-selected by the selection unit. The calculation unit calculates the load pattern of the drive unit based on the newly created calculation model. (More preferably, operating patterns and load patterns) We will perform a new calculation, The selection unit determines the newly calculated load pattern (More preferably, operating patterns and load patterns) The motor selection device described in item 8, which re-selects a motor that conforms to the above from the motor database.

[0035] This configuration allows the physical models of the motors not to be modified and the re-selected motors to complement the calculation model, enabling the calculation of the accurate load pattern of the drive unit while considering the influence of the selected motors. As a result, the motor that best fits the accurate load pattern can be appropriately re-selected.

[0036] 10. The selection unit determines that the motors not subject to modification are the newly calculated load patterns. (More preferably, operating patterns and load patterns) A motor selection device as described in item 9, for determining whether or not it conforms to the requirements.

[0037] This configuration allows for the determination of whether motors not subject to modification are suitable for the load pattern, thus preventing unsuitable motors from remaining selected. This supports the proper design of multi-axis machinery.

[0038] 11. An electric motor selection program that incorporates a set of steps to operate a computer as an electric motor selection device as described in any one of items 1 to 10.

[0039] By executing such an electric motor selection program on a computer, an electric motor selection device having the aforementioned characteristics can be constructed.

[0040] 12. A motor selection program incorporating a set of steps to control a computer including an input device, a display device and a storage device, so that the computer operates as a motor selection device according to any one of items 1 to 10.

[0041] 13. A computer-readable recording medium containing the motor selection program described in Section 11 or 12. The recording medium may be any form of computer-readable medium, such as semiconductor memory, optical recording medium, magnetic recording medium, or magneto-optical recording medium. [Effects of the Invention]

[0042] This invention provides an electric motor selection device and an electric motor selection program that facilitate the selection of multiple electric motors constituting a multi-axis machine. [Brief explanation of the drawing]

[0043] [Figure 1] Figure 1 is a block diagram illustrating an example of the configuration of an electric motor selection device according to one embodiment of the present invention. [Figure 2] Figure 2 is a diagram illustrating an example of a multi-axis machine. [Figure 3] Figure 3 is a block diagram illustrating the functional configuration of the motor selection device. [Figure 4] Figure 4 is a diagram illustrating an example of the configuration of an electric motor database. [Figure 5] Figure 5 shows an example of a display screen in a display device. [Figure 6] Figure 6 is a flowchart illustrating the process of selecting an electric motor. [Figure 7] Figure 7 is a flowchart showing the process for determining the suitability of the selection result by changing at least one of the mechanism specifications and operating conditions. [Figure 8A-8B] Figures 8A and 8B show examples of how the judgment results are displayed. [Figure 9]Figure 9 is a flowchart illustrating another embodiment of the present invention. [Figure 10] Figure 10 shows an example of a re-selection input screen. [Figure 11] Figure 11 shows an example of how the re-selection results are displayed. [Modes for carrying out the invention]

[0044] Hereinafter, embodiments of this invention will be described in detail with reference to the accompanying drawings.

[0045] Figure 1 is a block diagram illustrating an example configuration of an electric motor selection device according to one embodiment of the present invention. The electric motor selection device 1 has a basic configuration as a computer. That is, by installing the electric motor selection program 9 on the computer, the computer functions as the electric motor selection device 1. The electric motor selection device 1 includes a processor 2, memory 3, storage 4, input device 5, display device 6, communication interface 7, media reader 8, etc.

[0046] Memory 3 includes ROM and RAM. Storage 4 is an auxiliary storage device composed of large-capacity storage devices such as SSDs (Solid State Drives) and HDDs (Hard Disk Drives). Memory 3 and Storage 4 are examples of storage devices. The motor selection program 9 is installed on Storage 4.

[0047] Processor 2 executes the motor selection program 9 using the memory area of ​​memory 3 and implements various functions.

[0048] Input device 5 is a keyboard, pointing device, etc. Display device 6 is a two-dimensional display, etc. Input device 5 and display device 6 provide a human-machine interface.

[0049] The communication interface 7 mediates communication with local area networks and wide area networks (such as the Internet). The media reader 8 may include a disk drive that reads information from recording media such as Blu-ray discs, DVDs, and CDs. Alternatively, the media reader 8 may be a memory reader that reads information from recording media such as USB memory or memory cards. The motor selection program 9 recorded on the recording media may be read by the media reader 8 and installed into the computer. Alternatively, the motor selection program 9 may be downloaded via the communication interface 7 and installed into the computer. The computer on which the motor selection program 9 is installed performs the functions of the motor selection device 1, and the storage 4 on which the motor selection program 9 is stored may be an example of a recording media on which the motor selection program 9 is recorded.

[0050] The motor selection device 1 is a device that can be used to select multiple motors to be incorporated into a multi-axis machine as a drive source.

[0051] Figure 2 is a diagram illustrating an example of a multi-axis machine. Figure 2 shows an example configuration of a multi-axis machine 10 that constitutes a vertical articulated robot. A rotary base 12 is connected to a fixed base 11 so as to be rotatable around a vertical first rotation axis A1, and this connection constitutes the first joint J1. The base end of a first arm 13 is connected to the rotary base 12 so as to be rotatable around a horizontal second rotation axis A2, and this connection constitutes the second joint J2. The base end of a second arm 14 is connected to the tip of the first arm 13 so as to be rotatable around a horizontal third rotation axis A3, and this connection constitutes the third joint J3. A third arm 15 is connected to the tip of the second arm 14 so as to be rotatable around a horizontal fourth rotation axis A4, and this connection constitutes the fourth joint J4. An electric chuck 16 is attached to the tip of the third arm 15 so as to be rotatable around a fifth rotation axis A5 along the longitudinal direction of the third arm 15, and this attachment point constitutes the fifth joint J5. The electric chuck 16 is the machine end. The electric chuck 16 is configured to, for example, hold a workpiece 17 and release it. The first arm 13, the second arm 14, and the third arm 15 constitute a multi-joint arm that extends and retracts by bending and extending the arms at the joints J1 to J5.

[0052] The first joint J1, second joint J2, third joint J3, fourth joint J4, and fifth joint J5, as well as the electric chuck 16, each have a first drive shaft D1, second drive shaft D2, third drive shaft D3, fourth drive shaft D4, fifth drive shaft D5, and sixth drive shaft D6 (hereinafter collectively referred to as "drive shaft D") that receive driving force from an electric motor. The first drive shaft D1, second drive shaft D2, third drive shaft D3, fourth drive shaft D4, fifth drive shaft D5, and sixth drive shaft D6 are connected to a first electric motor M1, second electric motor M2, third electric motor M3, fourth electric motor M4, fifth electric motor M5, and sixth electric motor M6 (hereinafter collectively referred to as "electric motor M") that drives them, respectively. The drive shaft D is a drive unit driven by the electric motor M.

[0053] In this specification, the drive unit driven by the electric motor M is sometimes referred to as the drive shaft D, but this does not necessarily mean that all drive shafts D are axial. Some or all of the drive shafts D may be axial, or they may not be axial. For example, drive shafts D1 to D5 may be axial drive units (e.g., rotating shafts), and drive shaft D6 may be a non-axial drive unit (e.g., a linearly moving drive piece). Typically, the drive shafts D receive the driving force from the electric motor M and drive the mechanical elements coupled to the drive shafts D.

[0054] When the first motor M1 is driven, the rotating base 12 rotates relative to the fixed base 11 at the first joint J1, and a swivel motion is achieved in which the entire articulated arm rotates around the vertical first rotation axis A1. When the second motor M2 is driven, the articulated arm rotates around the horizontal second rotation axis A2, and an elevation motion is achieved. When the third motor M3 is driven, the second arm 14 rotates around the horizontal third rotation axis A3 relative to the first arm 13 to flex and extend, and when the fourth motor M4 is driven, the third arm 15 rotates around the horizontal fourth rotation axis A4 relative to the second arm 14 to flex and extend. When the fifth motor M5 is driven, the electric chuck 16 rotates on its own axis (so-called θ rotation) around the fifth rotation axis A5 relative to the third arm 15. When the sixth electric motor M6 is driven, the electric chuck 16 is operated to hold or release the workpiece 17.

[0055] By individually controlling the operation of the first to sixth electric motors M1 to M6, the vertical articulated robot can, for example, transport the workpiece 17 from one position to another.

[0056] Figure 3 is a block diagram illustrating the functional configuration of the motor selection device 1, representing multiple functions realized by the execution of the motor selection program 9 by a computer as functional blocks. Therefore, it can also be said that Figure 3 represents the configuration of the motor selection program 9. Specifically, the various functions shown in Figure 3 are realized when the processor 2 of the computer constituting the motor selection device 1 executes the motor selection program 9, and the motor selection device 1 essentially has various functional processing units, including the functional processing unit shown in Figure 3. In other words, the motor selection program 9 incorporates a set of steps such that, when executed by a computer, the computer functions as a motor selection device 1 having various functional processing units, including the functional processing unit shown in Figure 3.

[0057] The motor selection device 1 comprises several functional processing units, including a multi-axis machine model holding unit 20, an input unit 30, a calculation model creation unit 55, a calculation unit 50, and a selection unit 60. In this embodiment, the motor selection device 1 further includes a motor database 40. However, as will be described later, the motor database 40 can also be located on a server or the like that the motor selection device 1 can access via a network, so it is not essential that the motor selection device 1 includes the motor database 40.

[0058] The multi-axis machine model holder 20 holds information on multiple multi-axis machine models. A multi-axis machine model is a physical model that represents the configuration of a multi-axis machine. Multi-axis machine models are prepared to support various configurations of multi-axis machines, such as vertical articulated robots, horizontal articulated robots, parallel link robots, and gantry robots. The multi-axis machine models held in the multi-axis machine model holder 20 do not include the specifications of the electric motor M that drives the drive axis D, but they do include information indicating which machine element the electric motor M is attached to. The functions of the multi-axis machine model holder 20 are mainly realized by the storage 4.

[0059] The input unit 30 includes a model selection input unit 31, a mechanism specifications input unit 32, and an operating condition input unit 33. The functions of the input unit 30 are primarily realized by the processor 2 cooperating with the input device 5 and the display device 6.

[0060] The model selection input unit 31 receives selection input for selecting one multi-axis machine model from multiple multi-axis machine models held by the multi-axis machine model holding unit 20. Specifically, the user performs an input operation to select one multi-axis machine model by operating the input device 5 while referring to the display on the display device 6. The selection input is then accepted. The contents of the selection input are stored in the memory 3 or storage 4.

[0061] The mechanism specification input unit 32 accepts input of mechanism specifications for the selected multi-axis machine model. Mechanism specifications are information about each machine element that makes up the multi-axis machine model, such as the dimensions and mass of the machine elements. For example, for the selected multi-axis machine model, one or more input fields for mechanism specifications to be set are displayed on the display device 6, and the user enters specific mechanism specifications (typically numerical values) into each input field. These entered mechanism specifications are accepted. The accepted mechanism specifications are stored in the memory 3 or storage 4. The mechanism specifications that the user should set from the mechanism specification input unit 32 are the mechanism specifications of the machine elements other than the electric motor in the multi-axis machine model.

[0062] The operating condition input unit 33 accepts input of operating conditions for the selected multi-axis machine model. Operating conditions are typically information that defines the load and operation at the machine end of the multi-axis machine model. Information defining the load includes, for example, the mass and moment of inertia of the workpiece 17 held at the machine end. Information defining the operation is a machine end operating pattern that represents, for example, the time change in the position of the workpiece 17 held at the machine end (position pattern), the time change in velocity (direction and speed) (velocity pattern), and the time change in acceleration (acceleration pattern). The machine end operating pattern may be a single pattern or a combination of multiple patterns. For example, input fields for numerical values ​​defining the operating conditions are displayed on the display device 6, and the user enters specific numerical values ​​into each input field. The operating conditions thus entered are accepted. The accepted operating conditions are stored in the memory 3 or storage 4.

[0063] The operating condition input unit 33 may be configured to accept input of operating patterns for one or more drive axes D of the selected multi-axis machine model as operating conditions. That is, operating patterns representing the rotational position pattern, rotational speed pattern, rotational acceleration pattern, etc., of the drive axis D may be input. In this case as well, the operating pattern may be a single pattern or a combination of multiple patterns.

[0064] The motor database 40 stores model identification information, physical model information, and characteristic information for multiple motors that could be selected as candidates. The functions of the motor database 40 are primarily realized by the storage 4. The information stored in the motor database 40 will be described later.

[0065] The calculation model creation unit 55 applies the mechanism specifications received by the mechanism specification input unit 32 to the selected multi-axis machine model to create a calculation model. Furthermore, if an electric motor M for any of the drive axes D has already been selected, the calculation model creation unit 55 creates a calculation model that incorporates the physical model of the selected electric motor M.

[0066] The calculation unit 50 calculates the operating pattern and load pattern for each of the multiple drive axes D that constitute the selected multi-axis machine model. The calculation unit 50 includes an operating pattern calculation unit 51 that calculates the operating pattern, an operating pattern holding unit 52 that holds the calculated operating pattern, and a load calculation unit 53 that calculates the load pattern.

[0067] A driving pattern refers to information that represents the rotational position, rotational speed (direction and speed of rotation), rotational acceleration, etc., of each drive shaft D in chronological order. The driving pattern calculation unit 51 calculates the driving patterns for each of the multiple drive shafts D to satisfy the input driving conditions, based on the calculation model created by the calculation model creation unit 55. However, if the driving pattern of any of the drive shafts D is input from the driving condition input unit 33, the calculation of the driving pattern for that drive shaft D is omitted, and the input driving pattern is used as is. If a machine end driving pattern is input, the driving pattern calculation unit 51 calculates the driving patterns for all drive shafts D by performing inverse kinematics calculations based on the calculation model. The calculated driving pattern data is stored in the driving pattern holding unit 52.

[0068] A load pattern refers to information representing the time-dependent change in load torque applied to each drive shaft D in a time-series manner when each drive shaft D is operated according to an operating pattern. The load calculation unit 53 calculates the load pattern of the drive shafts D based on the calculation model created by the calculation model creation unit 55 and the operating pattern held by the operating pattern holding unit 52. More specifically, the load calculation unit 53 calculates the load inertia moment (inertial load) of the drive shaft D based on the calculation model, and calculates the load pattern based on this load inertia moment and the motion pattern of the drive shaft D. The load calculation unit 53 may also calculate the load pattern by dynamic calculations (equations of motion using the Lagrangian method or the Newton-Euler method) based on the calculation model. This allows for the accurate calculation of the load pattern of the motor M of each drive shaft D, taking into account the unique load patterns that occur in multi-axis machines (for example, centrifugal force and Coriolis force).

[0069] The selection unit 60 selects an electric motor suitable for driving each drive shaft D based on the load pattern calculated by the calculation unit 50 for each drive shaft D (and, if necessary, the operating pattern and load inertia moment). That is, the selection unit 60 refers to the electric motor database 40 to select an electric motor having characteristics that match the load pattern of each drive shaft D, and outputs model identification information for the selected electric motor. In this embodiment, the selection unit 60 selects the smallest size electric motor having the necessary characteristics to satisfy the load pattern of each drive shaft D. The smallest size may be a specific dimension such as the smallest mounting angle dimension, or it may be the smallest mass. The selection unit 60 may search the electric motors registered in the electric motor database 40 in order from the smallest size (for example, from the smallest mounting angle dimension) and examine their characteristic information, and output the first electric motor whose characteristic information matches the load pattern as the selection result for each drive shaft D. That is, smaller sizes may have a higher priority.

[0070] The selection unit 60 selects target drive axes D in order from the machine end (load end) side of the multi-axis machine model (calculation model), and selects an electric motor from the electric motor database 40 that satisfies the load pattern of the target drive axis D. More specifically, if the multi-axis machine model has N drive axes D1 to DN in order toward the machine end, such as the first drive axis D1, the second drive axis D2, ..., to the Nth drive axis DN (N is a natural number of 2 or more; in the example in Figure 2, N=6), the electric motors are selected in order from the Nth drive axis DN closest to the machine end. Once the selection of the electric motor Mn for the nth drive axis Dn (n is a natural number of 2 or more and less than or equal to N) is complete, the electric motor M(n-1) for the (n-1)th drive axis D(n-1) is selected. By repeating the selection of electric motors M until n=2, it is possible to select N electric motors M (i.e., all electric motors) that drive each of the N drive axes D.

[0071] When the selection unit 60 selects an electric motor M for a certain drive shaft D, the calculation model creation unit 55 retrieves the physical model of the selected electric motor M from the electric motor database 40 and complements it with the previous calculation model. That is, the calculation model creation unit 55 incorporates the physical model of the selected electric motor M into the previous calculation model to update the calculation model and create a calculation model with the electric motor incorporated. More specifically, when the selection unit 60 completes the selection of the nth electric motor MN that drives the nth drive shaft DN closest to the machine end, the physical model of the nth electric motor MN is complemented with the initial calculation model that reflects the mechanism specifications in the multi-axis machine model (basic physical model), and an updated calculation model is constructed. When the selection unit 60 completes the selection of the nth electric motor Mn that drives the nth drive shaft Dn, the calculation model creation unit 55 complements the latest calculation model with the physical model of the nth electric motor Mn and updates the calculation model.

[0072] The load calculation unit 53 uses the latest calculation model to calculate the load pattern of the drive shaft D that constitutes the latest calculation model. Once the selection of the nth motor Mn corresponding to the nth drive shaft Dn is complete, the latest calculation model has the physical models of the 1st to nth motors M1 to Mn already incorporated. The load calculation unit 53 uses the latest calculation model to calculate the load pattern for the drive shaft D for which the selection of a motor M has not yet been completed (more specifically, at least the (n-1)th drive shaft D(n-1) for which a motor should be selected next). Then, the selection unit 60 selects the (n-1)th motor M(n-1) that is suitable for the (n-1)th drive shaft D(n-1) based on the load pattern of the (n-1)th drive shaft D(n-1) calculated in this way.

[0073] The function processing unit of the computer constituting the motor selection device 1 further includes a selection result display unit 61. The selection result display unit 61 displays information about the motor M selected by the selection unit 60. The displayed information about the motor M includes at least the model identification information of the selected motor M. For example, the selection result display unit 61 obtains the model identification information of the selected motor M from the motor database 40 and displays it on the display screen of the display device 6. The functions of the selection result display unit 61 are mainly realized by the processor 2 and the display device 6.

[0074] The function processing unit of the computer constituting the motor selection device 1 further includes a selection result storage unit 62 that stores the motor selection results. The selection result storage unit 62 stores information for identifying the motor M selected by the selection unit 60. The information for identifying the motor M is information that can identify an entry (or record) in the motor database 40, and may also be model identification information for the selected motor M. The selection result storage unit 62 may also store some or all of the following: information for identifying the multi-axis machine model received and selected by the model selection input unit 31, mechanism specifications received by the mechanism specifications input unit 32, and operating condition information received by the operating condition input unit 33. The functions of the selection result storage unit 62 are mainly realized by the processor 2 and the storage 4.

[0075] The function processing unit of the computer constituting the motor selection device 1 further includes a determination unit 70 and a determination result display unit 71. The determination unit 70 determines whether the selection result stored in the selection result storage unit 62 conforms to the mechanism specifications received by the mechanism specification input unit 32 and the operating conditions received by the operating condition input unit 33. More specifically, by utilizing the function of the determination unit 70, it is possible to determine whether the previous selection result still conforms to the changed mechanism specifications / operating conditions when at least one of the mechanism specifications or operating conditions is changed. The determination result display unit 71 displays the result of the determination by the determination unit 70. The function of the determination unit 70 is mainly implemented by the processor 2, and the function of the determination result display unit 71 is mainly implemented by the processor 2 and the display device 6.

[0076] Figure 4 is a diagram illustrating an example configuration of the motor database 40. Preferably, the motor database 40 is configured by storing information on all motors that can be selected as drive sources for multi-axis machines in storage 4. All motors may include, for example, all motors that a particular motor manufacturer, a particular motor vendor, etc., can provide as drive sources for multi-axis machines. The data stored in the motor database 40 includes model identification information 41 for all motors, physical model information 42 for all motors, and characteristic information 43 for all motors. For example, for each individual motor, an entry may be created linking the model identification information 41, physical model information 42, and characteristic information 43 and stored in storage 4.

[0077] Model identification information 41 is information that identifies the model of the electric motor, and is typically model number information. Model number information is information that represents the model number of the electric motor, and is information that identifies the model of the electric motor that can be provided by, for example, an electric motor manufacturer or electric motor distributor, and can also be called model name information.

[0078] The physical model information 42 is information used to identify the physical model of the electric motor. When the electric motor is incorporated into the multi-axis machine 10, it also becomes part of the load on the drive shaft D, which is further from the machine end. Therefore, the physical model of the electric motor includes the mechanical information necessary for calculating the load pattern of the drive shaft D of the multi-axis machine 10. Specifically, the physical model of the electric motor includes information such as the shape, dimensions, mass, center of gravity, and rotor moment of inertia of the electric motor.

[0079] The motor characteristic information 43 is information that represents the characteristics of the motor, and mainly includes the characteristics necessary to determine whether the motor is suitable for the load pattern. Specifically, the motor characteristic information 43 includes, for example, the motor rated speed, rated torque, allowable moment of inertia, torque-speed characteristic data, etc. The torque-speed characteristic data is information that represents the characteristics of the output torque with respect to rotational speed. For motors that have a flat torque characteristic in the rotational speed range below the rated rotational speed (brushless motors and servo motors), the characteristic information may also include capacity (output). For example, in the case of a stepping motor, it does not have a flat torque characteristic, and the output torque fluctuates with rotational speed over almost the entire usable rotational speed range. For motors of this type with such characteristics, since the capacity (output) changes with rotational speed, it is more appropriate to include torque-speed characteristic data rather than capacity as characteristic information. If necessary, by referring to the torque-speed characteristic data, the capacity (output) in the rotational speed range actually used can be calculated based on the operating pattern and load pattern.

[0080] The selection unit 60 may, if necessary, perform such capacity calculations to select an electric motor. Similarly, the determination unit 70 may, if necessary, perform capacity calculations based on torque-speed characteristic data to determine whether the selected electric motor is suitable or unsuitable. Specifically, the selection unit 60 and the determination unit 70 identify the operating speed range and the load torque in the operating speed range based on the driving pattern and load pattern of the drive shaft D, and determine the required capacity conditions in the operating speed range. The selection unit 60 then searches the electric motor database 40 and selects an electric motor (more specifically, the smallest size electric motor) that has torque-speed characteristics that satisfy the capacity conditions in the operating speed range. Similarly, the determination unit 70 refers to the electric motor database 40 and determines whether the torque-speed characteristics of the selected electric motor satisfy the capacity conditions in the operating speed range.

[0081] Figure 5 shows an example of a display screen in the display device 6. The display screen has an input area 80, a multi-axis machine model display area 87, and a selection result display area 88. The input area 80 includes a multi-axis machine model selection button 81, a mechanism specifications input button 82, and an operating condition input button 83. For example, by operating the multi-axis machine model selection button 81, a selection screen containing illustrations of multiple multi-axis machine models may be displayed, and any of the multi-axis machine models can be selected by operating on that selection screen. Once a multi-axis machine model is selected, a diagram of the selected multi-axis machine model is displayed in the multi-axis machine model display area 87. Furthermore, by operating the mechanism specifications input button 82 after selecting a multi-axis machine model, an input screen for inputting specification information of the machine elements constituting the selected multi-axis machine model may be displayed. Additionally, by operating the operating condition input button 83, an operating condition input screen may be displayed. The user can input operating conditions from that input screen. Operating conditions may include time changes in the position, speed, acceleration, etc., of the machine ends of the multi-axis machine model. Furthermore, the operating conditions may also be time-varying parameters such as the rotational position, rotational speed, and rotational acceleration of a specific drive axis of the multi-axis machine model.

[0082] In the multi-axis machine model display area 87, some or all of the mechanism specifications may be entered by specifying the configuration of the displayed multi-axis machine model. For example, the mechanism specifications may be entered by changing the arm length of the displayed multi-axis machine model by dragging, changing the direction of the rotation axis (vertical or horizontal) by clicking, or by clicking on the arm and then typing the mass of the arm.

[0083] Furthermore, in the multi-axis machine model display area 87, some or all of the operating conditions may be entered by specifying the operation of the displayed multi-axis machine model. For example, the mass and dimensions of the workpiece 17 may be entered by keying after clicking on the machine end, the movement path of the machine end may be entered by dragging the machine end, or the operation order and linkage of specific arms may be specified by clicking or keying.

[0084] Inputting mechanism specifications and / or motion conditions by operating the multi-axis machine model display area 87 would be even easier if a three-dimensional model of the multi-axis machine model were displayed. Preferably, the display of the multi-axis machine model in the multi-axis machine model display area 87 reflects the input mechanism specifications. This allows for visual confirmation of the structure of the multi-axis machine, making it easier to verify that there are no errors in the input. Furthermore, it is preferable that the multi-axis machine model display area 87 allows for video display of the multi-axis machine model operating according to the input motion conditions. This allows for visual confirmation of the operation of the multi-axis machine, making it easier to verify that there are no errors in the input of motion conditions.

[0085] The display screen of the display device 6 may include a selection button 84 for instructing the start of the motor selection process. This selection button 84 may be activated when a multi-axis machine model is selected and the necessary mechanism specifications and operating conditions have been entered.

[0086] The selection result display area 88 displays information identifying the electric motors M selected to drive each of the multiple drive axes D of the multi-axis machine model, typically model identification information (more specifically, model number information). In the illustrated example, the model identification information A, B, F, G, L, K of the selected electric motors M1 to M6 are displayed. These represent, for example, the combination of the smallest sized electric motors that fit the load pattern of each drive axis D.

[0087] Figure 6 is a flowchart illustrating the motor selection process. The user selects a multi-axis machine model by operating the input device 5 while referring to the display on the display device 6 (step S1), inputs the mechanical specifications of the selected multi-axis machine model (step S2), and then inputs the operating conditions of that multi-axis machine model (step S3). Once the input is complete, the user operates the selection button 84 to command the start of the motor selection process (step S4).

[0088] In response, the calculation model creation unit 55 applies the input mechanism specifications to the selected multi-axis machine model to create the initial calculation model (step S5). The operation pattern calculation unit 51 calculates the operation pattern for each drive axis D based on the calculation model and operating conditions (step S6). The calculated operation patterns are stored in the operation pattern holding unit 52 (step S6).

[0089] Next, the load calculation unit 53 calculates the load pattern of the drive shaft D closest to the machine end, i.e., the Nth drive shaft DN, based on the calculation model and the operating pattern at the machine end. Based on this calculated load pattern (and the operating pattern and load inertia moment as needed), the selection unit 60 searches the motor database 40 (step S8) and selects the smallest motor with characteristic information that satisfies the load pattern as the Nth motor MN (step S9). The selection result is stored in the selection result storage unit 62 (step S10). If no motor with characteristic information that satisfies the load pattern is found (step S9: NO), the selection result display unit 61 displays "Not selectable" (step S14). The process then ends. In this case, the user returns to the first step and changes at least one of the multi-axis machine model (step S1), mechanism specifications (step S2), and operating conditions (step S3) to redo the motor selection.

[0090] When the motor (the Nth motor MN) that matches the load pattern of the drive shaft D closest to the machine end, i.e., the Nth drive shaft DN, has been selected (Step S9: YES), the motor selection device 1 determines whether the motor (the first motor M1) of the last drive shaft D in the selection order, i.e., the first drive shaft D1, has been selected (Step S11). If this determination is negative, i.e., if there are still drive shafts D to which motor M should be selected (Step S11: NO), the calculation model creation unit 55 obtains the physical model of the Nth motor MN from the motor database 40, and updates the calculation model by supplementing the previous calculation model with that physical model (Step S12). Using the updated calculation model, the load calculation unit 53 calculates the load pattern of the drive shaft D next closest to the machine end, i.e., the (N-1)th drive shaft D(N-1) (Step S13). Based on the calculated load pattern, the selection unit 60 searches the motor database 40 (step S8) and selects the smallest motor with characteristic information that satisfies the load pattern as the (N-1) motor M(N-1) (step S9). The selection result is stored in the selection result storage unit 62 (step S10). If no motor with characteristic information that satisfies the load pattern is found (step S9: NO), the selection result display unit 61 displays "Not selectable" (step S14). The process then ends.

[0091] When the motor M(N-1) that matches the load pattern of the (N-1) drive shaft D(N-1) has been selected, the motor selection device 1 determines whether the motor for the last drive shaft D in the selection order, i.e., the motor for the first drive shaft D1 (first motor M1), has been selected (step S11). If this determination is negative, i.e., if there are still drive shafts D for which motor M should be selected (step S11: NO), the process from step S12 is repeated. That is, the calculation model creation unit 55 obtains the physical model of the nth motor Mn from the motor database 40, and updates the calculation model by supplementing the previous calculation model with that physical model (step S12). Using the updated calculation model, the load calculation unit 53 calculates the load pattern of the next closest drive shaft D(n-1) to the machine end (step S13), and the selection unit 60 selects the smallest electric motor with characteristic information that satisfies that load pattern as the (n-1) electric motor M(n-1) (step S9: YES), and stores the selection result in the selection result storage unit 62. If selection is not possible (step S9: NO), the system displays a message to that effect on the display device 6 and terminates the process (step S14). This process is repeated until the last drive shaft D, i.e., the first drive shaft D1 (step S11).

[0092] When all motors that match the load patterns of all drive shafts D, i.e., the first to ninth drive shafts D1 to DN, i.e., the first to nth motors MN, have been selected (step S11: YES), the selection result display unit 61 displays the selection results stored in the selection result storage unit 62 on the display device 6 (step S15). The process then ends.

[0093] In this way, all the electric motors M to be incorporated into the multi-axis machine 10 can be selected at once, and the selection results can be obtained. Since each of the selected electric motors M is the smallest size that fits the load pattern of the target drive axis D, a reasonable selection result can be provided. The selection of multiple electric motors M is performed sequentially from the drive axis D closest to the machine end of the multi-axis machine model (computational model), and the selection of electric motors M proceeds while complementing the computational model with the physical model of the selected electric motors M. Therefore, since the selection of electric motors is made to fit the load pattern with the selected electric motors M incorporated, a multi-axis machine with a reasonable configuration can be designed using the selection results as is. In addition, since multiple electric motors M can be selected at once, the effort and time required for designing the multi-axis machine can be significantly reduced. Specifically, since the design and operating conditions can be changed without much consideration of the effort involved in selecting electric motors M, flexible design becomes possible, and changes in operating conditions can be easily accommodated.

[0094] The motor selection device 1 may also have a function to display the load pattern of each drive shaft D and the suitability of the selected motor M. The suitability may be a numerical value representing the degree to which the characteristics of the motor M (for example, the capacity value in the operating speed range) match the load pattern. The load pattern of each drive shaft D is the sum of the load patterns generated from various physical factors such as inertia term, centrifugal force, Coriolis term, gravity term, and friction term that occur during acceleration / deceleration. The breakdown of such load patterns may be displayed on the display device 6.

[0095] In particular, it is preferable that the motor selection device 1 has a function to display on the display device 6 the model identification information of the motor with the highest degree of suitability and the suitability of that motor model when a motor M for any of the drive shafts D is unsuitable for selection. Furthermore, the motor selection device 1 may also have a function to display the breakdown of the load pattern as described above, and to present specific revision proposals for the selection conditions on the screen of the display device 6. The selection conditions specifically refer to the mechanism specifications and / or operating conditions. Specific examples of proposed revisions include reducing the load, reducing acceleration or deceleration, and reducing speed.

[0096] Figure 7 is a flowchart showing the flow when determining the suitability of the selection result after changing at least one of the mechanism specifications and operating conditions. The determination unit 70 (see Figure 3) determines whether the multiple electric motors M represented by the selection results stored in the selection result storage unit 62 conform to the mechanism specifications and operating conditions.

[0097] It is a given that the multiple electric motors M selected based on the mechanism specifications received by the mechanism specifications input unit 32 and the operating conditions received by the operating condition input unit 33 satisfy those mechanism specifications and operating conditions. However, after the multiple electric motors M have been selected, the user may wish to change at least one of the mechanism specifications and operating conditions. In this case, the determination unit 70 determines whether the selected electric motors M conform to the changed mechanism specifications and operating conditions. The determination result display unit 71 displays conformance / conformance information for each of the multiple electric motors M on the display device 6. For example, as shown in Figure 5, a determination button 85 may be placed on the display screen of the display device 6. This determination button 85 may become active and operable when the selection results are stored in the selection result storage unit 62 and the mechanism specifications and / or operating conditions are changed.

[0098] Referring to Figure 7, the operator operates the mechanism specifications input unit 32 and / or the operating condition input unit 33 to change at least one of the mechanism specifications and operating conditions (steps S21, S22). After completing the change, the operator operates the determination button 85 to command the start of the determination (step S23).

[0099] Then, the calculation model creation unit 55 reconstructs the calculation model based on the mechanism specifications and operating conditions, at least one of which has been changed. At this time, the calculation model creation unit 55 refers to the selection result storage unit 62 and incorporates the physical model of the selected electric motor M into the calculation model, creating a calculation model of the multi-axis machine with all electric motors M incorporated (step S24).

[0100] The driving pattern calculation unit 51 calculates the driving pattern for each drive shaft D based on its calculation model and stores it in the driving pattern holding unit 52 (step S25). The load calculation unit 53 calculates the load pattern for each drive shaft D based on its calculation model (step S26).

[0101] The determination unit 70 refers to the motor database 40 to examine the characteristic information of the selected motors M for each drive shaft D (step S27) and determines whether each selected motor M is suitable for the load pattern of the corresponding drive shaft D (step S28). Specifically, the determination unit 70 determines whether the selected motor M has sufficient characteristics (especially sufficient torque characteristics in the operating speed range) for the load pattern. Then, for each drive shaft D, the suitability / unsuitability of the selected motor M is displayed on the display device 6 by the determination result display unit 71 (step S29).

[0102] Figures 8A and 8B show examples of how the judgment results are displayed. Figure 8A is an example of how the results are displayed when all selected motors M conform to the modified mechanism specifications / operating conditions. Figure 8B is an example of how the results are displayed when, among the selected motors, the first to third motors M1 to M3 are deemed unsuitable, and the fourth to sixth motors M4 to M6 are deemed suitable.

[0103] The user is notified of the judgment result in this manner. The user can further modify the mechanism specifications / operating conditions and have the motor selection device 1 perform the same judgment repeatedly (see Figure 7). In addition, if some of the motors M are unsuitable, the user can re-select all of the motors M based on the modified mechanism specifications / operating conditions (see Figure 6). When changing the multi-axis machine model, the conditions are completely different, so it is necessary to re-select all of the motors M.

[0104] The motor selection device 1 may also have a function to display the suitability of any motor M on the display device 6 if it is determined that any of the motors M are unsuitable. Furthermore, the motor selection device 1 may also have a function to display the breakdown of the load patterns as described above, or to present specific revision proposals for the selection conditions (specifically, the mechanical specifications or operating conditions) on the screen of the display device 6.

[0105] Figure 9 is a flowchart illustrating the features of another embodiment of the present invention. In describing this embodiment, Figures 1 to 8 described above will be referred to again. Also, in Figure 9, the same reference numerals are used for steps corresponding to the steps shown in Figure 6.

[0106] This embodiment provides a function to redo the selection of some or all of the electric motors M of the multi-axis machine 10 after the selection of the electric motors M has been performed. For example, it is possible to redo the selection of the remaining electric motors M while maintaining the selection results of some of the electric motors M. More specifically, the suitability of the existing selection results can be determined by changing the mechanism specifications and / or operating conditions (see Figures 7 and 8), and if some of the electric motors M are determined to be unsuitable, re-selection can be performed only for the electric motors M that were determined to be unsuitable.

[0107] The function processing unit of the computer constituting the motor selection device 1 includes a selection modification input unit 35, as shown in Figure 3. The selection modification input unit 35 receives selection modification commands that instruct the re-selection of some or all of the selection results stored in the selection result storage unit 62. A typical example of a selection modification command is a command that accepts the selection of at least one of a plurality of already selected motors M and fixes that selection result, while excluding at least one of the remaining motors M from the selection candidates. The function of the selection modification input unit 35 is mainly realized by the processor 2, the input device 5, and the display device 6. For example, as shown in Figure 5, a re-selection input button 86 may be placed in the input area 80 of the display screen of the display device 6. This re-selection input button 86 may be in an operable active state when the selection results are stored in the selection result storage unit 62.

[0108] Referring to Figure 9, the user operates the input device 5 while referring to the display on the display device 6 to select a multi-axis machine model (step S1), input the mechanism specifications of the selected multi-axis machine model (step S2), and then input the operating conditions of that multi-axis machine model (step S3). Although not shown in the diagram, if a multi-axis machine model different from the multi-axis machine model corresponding to the selection result stored in the selection result storage unit 62 is selected, that is, when the multi-axis machine model is changed, the selection result in the selection result storage unit 62 is cleared. When the selection result storage unit 62 holds a selection result, the re-selection input button 86 is displayed in an active state. When the operator operates the re-selection input button 86, the re-selection input screen (selection correction input screen) is displayed on the display device 6 by the function of the selection correction input unit 35 (step S31).

[0109] Figure 10 shows an example of a re-selection input screen. The user can select some or all of the electric motors M that make up the multi-axis machine 10 as targets for re-selection (target for modification). In the illustrated example, the first electric motor M1 for overall rotation, the second electric motor M2 for driving the first arm 13, and the third electric motor M3 for driving the second arm 14 are designated as targets for re-selection. On the other hand, the fourth electric motor M4 for driving the third arm 15, the fifth electric motor M5 for rotating the tip (θ rotation), and the sixth electric motor M6 for driving the electric chuck 16 are not designated as targets for re-selection, and it is specified that the selected electric motors should be used as they are.

[0110] The user specifies at least one electric motor M to be re-selected and operates the selection button 84 to command the start of re-selection (step S4 in Figure 9). The calculation model creation unit 55 then creates a calculation model by applying the input mechanism specifications to the selected multi-axis machine model (step S5). The operation pattern calculation unit 51 calculates the operation pattern for each drive axis D based on the created calculation model and the input operating conditions, and stores it in the operation pattern holding unit 52 (step S6).

[0111] Next, the load calculation unit 53 calculates the load pattern of the drive shaft D closest to the machine end, i.e., the Nth drive shaft DN (Step S7). Then, it is determined whether the motor MN of the Nth drive shaft DN is subject to re-selection (Step S32). If it is not subject to re-selection (Step S32: NO), the determination unit 70 refers to the motor database 40 (Step S33) and determines whether the selected Nth motor MN has characteristic information that satisfies the calculated load pattern (Step S34). If this determination is positive, it is determined whether there are any remaining drive shafts D for which motor M should be selected / determined (Step S11). If the determination in Step S34 is negative, "Not selectable" is displayed on the display device 6 (Step S14), and the process ends. At this time, it is preferable to also display which motor M of which multi-axis machine model is not selectable. In this case, the user returns to the first procedure and changes at least one of the multi-axis machine model, mechanism specifications, and operating conditions to re-select the motor M.

[0112] If the motor MN of the Nth drive shaft DN is subject to re-selection (Step S32: YES), the selection unit 60 searches the motor database 40 based on the calculated load pattern (Step S8) and selects the smallest sized motor with characteristic information that satisfies the load pattern as the Nth motor MN (Step S9). The selection unit 60 may exclude motors that are already stored in the selection result storage unit 62 as previous selection results for the Nth motor MN from the candidates. The selection result is stored in the selection result storage unit 62 (Step S10). If no motor with characteristic information that satisfies the load pattern is found (Step S9: NO), the selection result display unit 61 displays "Not selectable" (Step S14). The process then ends.

[0113] When the motor (the Nth motor MN) that matches the load pattern of the drive shaft D closest to the machine end, i.e., the Nth drive shaft DN, has been selected (Step S9: YES), and when the Nth motor MN, which is not subject to re-selection, is determined to match the load pattern of the Nth drive shaft DN (Step S34: YES), it is determined whether the selection / determination of the motor (the first motor M1) for the last drive shaft D in the selection order, i.e., the first drive shaft D1, has been completed (Step S11). If this determination is negative, i.e., when there are still drive shafts D for which motor M should be selected / determined (Step S11: NO), the calculation model creation unit 55 obtains the physical model of the Nth motor MN from the motor database 40, and updates the calculation model by supplementing the previous calculation model with that physical model (Step S12). Using the updated calculation model, the load calculation unit 53 calculates the load pattern of the drive shaft D closest to the machine end, i.e., the (N-1) drive shaft D(N-1) (step S13).

[0114] Next, it is determined whether the motor M(N-1) of the (N-1) drive shaft D(N-1) is subject to re-selection (step S32). If it is not subject to re-selection, the determination unit 70 refers to the motor database 40 (step S33) and determines whether the selected (N-1) motor M(N-1) has characteristic information that satisfies the calculated load pattern (step S34). If this determination is affirmative, the process proceeds to the drive shaft D closest to the machine end (step S11). If the above determination is negative, "Not selectable" is displayed on the display device 6 (step S14), and the process ends.

[0115] If the (N-1) motor M(N-1) is subject to re-selection (Step S32: YES), the selection unit 60 searches the motor database 40 based on the calculated load pattern (Step S8) and selects the smallest sized motor with characteristic information that satisfies the load pattern as the (N-1) motor M(N-1) (Step S9). However, the selection unit 60 may exclude from the candidates motors that are already stored in the selection result holding unit as the previous selection result for the (N-1) motor M(N-1). The selection result is stored in the selection result storage unit 62 (Step S10). If no motor with characteristic information that satisfies the load pattern is found (Step S9: NO), the selection result display unit 61 displays "Not selectable" (Step S14). The process then ends.

[0116] When an electric motor (motor M(N-1)) that matches the load pattern of the (N-1) drive shaft D(N-1) has been selected (step S9: YES), and when it is determined that the (N-1) motor M(N-1) that is not subject to re-selection matches the load pattern of the (N-1) drive shaft D(N-1) (step S34: YES), it is determined whether the selection / determination of the motor (motor M1) for the last drive shaft D, i.e., the first drive shaft D1, has been completed (step S11). If this determination is negative, i.e., if there are still drive shafts D for which motor M should be selected (step S11: NO), the process from step S12 is repeated. In other words, once the nth motor Mn that matches the load pattern of the nth drive shaft Dn is determined, the calculation model creation unit 55 obtains the physical model of the nth motor Mn from the motor database 40, and updates the calculation model by supplementing it with the previous calculation model (step S12). Using the updated calculation model, the load calculation unit 53 calculates the load pattern of the (n-1)th drive shaft D(n-1) that is next closest to the machine end (step S13). If the (n-1)th motor M(n-1) is not subject to re-selection (step S32: NO), the determination unit 70 determines whether the selected (n-1)th motor M(n-1) satisfies the load pattern. If the (n-1)th motor M(n-1) is subject to re-selection (Step S32: YES), the selection unit 60 selects the smallest motor with characteristic information that satisfies the load pattern as the (n-1)th motor M(n-1) (Step S9: YES), and stores the selection result in the selection result storage unit 62 (Step S10). However, the selection unit 60 may exclude from the candidates any motors that are already stored in the selection result holding unit as the previous selection result for the (n-1)th motor M(n-1). If selection is not possible (Step S9: NO), the system displays this fact on the display device 6 and terminates the process (Step S14). This process is repeated until the last drive shaft D, i.e., the first drive shaft D1 (Step S11).

[0117] Once all motors that match the load patterns of all drive shafts D, i.e., the first to ninth drive shafts D1 to DN, i.e., the first to ninth motors M1 to MN, have been selected (step S11: YES), the selection result display unit 61 displays the selection results stored in the selection result storage unit 62 on the display device 6 (step S15). The process then ends.

[0118] In addition, when creating the initial calculation model in step S5, it is also possible to create a calculation model that incorporates the physical model of the motor M that is not subject to re-selection (i.e., already selected). In this case, it is sufficient to omit updating the calculation model (step S12) when the motor M that is not subject to re-selection satisfies the load pattern (step S34: YES).

[0119] Figure 11 shows an example of the re-selection results display, illustrating the display in the selection result display area 88 (see Figure 5). In the illustrated example, information A', B', F', G, L, and K, which identify the selected motors, are displayed as the first to fifth motors M1 to M5. In this example, information A', B', and F' are model identification information for the first, second, and third motors M1 to M3, which differ from the previous selection results (see Figure 5), while information G, L, and K are model identification information for the fourth, fifth, and sixth motors M4 to M6, which are the same as the previous selection results.

[0120] In this way, the remaining motors M can be re-selected while maintaining the previous selection results for some of the motors M. This brings the design closer to the optimal multi-axis machine required by the user. Moreover, since multiple motors M can be re-selected at once, the effort and time required for designing the multi-axis machine can be significantly reduced. Specifically, since the design and operating conditions can be changed without much consideration of the effort involved in selecting motors M, flexible design becomes possible, and changes in operating conditions can be easily accommodated.

[0121] The motor selection device 1 may have a function to display on the display device 6 the model identification information of the motor with the highest degree of suitability and the suitability of that motor model if the motor M of any of the drive shafts D is deemed unsuitable for re-selection and / or unsuitable. The motor selection device 1 may also have a function to display the breakdown of the load patterns as described above, and to present specific revision proposals for the selection conditions (specifically, the mechanism specifications or operating conditions) on the screen of the display device 6.

[0122] While embodiments of this invention have been described above, this invention can be implemented in other forms.

[0123] For example, in the embodiment described above, an example was described in which the motor database 40 is provided on the computer constituting the motor selection device 1. However, the motor database 40 may be located at a different location on the network accessible by the computer. That is, the motor database 40 may be located on a server connected to a network such as a local area network or the Internet, and the computer may access the motor database 40 via the communication interface 7. Alternatively, the motor selection program may be embedded in the server, and the server may provide the motor selection process, for example, as a web application service. In this case, the server operates to execute the motor selection process in response to input from a client connected via the network and to send the selection result to the client. Even in this case, it is not necessary to have the motor database on the same server; the motor database may be provided by another server.

[0124] Furthermore, while the above-described embodiment described a configuration in which the smallest size electric motor suitable for the load pattern of each drive shaft is selected, the priority conditions followed by the selection unit 60 when selecting an electric motor may be determined by criteria other than size. For example, criteria such as the type of electric motor, capacity, and price may be applied. Also, the configuration may allow for the selection of the priority conditions followed by the selection unit 60 when selecting an electric motor. For example, when size is used as the criterion, the mounting angle dimension, mass, and other size definitions may be selectable. Also, priority conditions such as size, electric motor type, capacity, and price may be selectable.

[0125] Furthermore, various design modifications can be made within the scope of the matters described in the patent claims. [Explanation of Symbols]

[0126] 1: Motor selection device 2: Processor 3: Memory 4: Storage 5: Input device 6:Display device 9: Motor Selection Program 10: Multi-axis machine 11: Fixed base 12: Rotating base 13: First Arm 14: Second Arm 15: Third Arm 16: Electric chuck 17: Work 20: Multi-axis machine model holder 30: Input section 31: Model Selection Input Section 32: Mechanism Specifications Input Section 33: Operating Condition Input Section 35: Selection Correction Input Section 40: Electric Motor Database 41: Model Identification Information 42: Physical Model Information 43: Characteristic Information 50: Arithmetic section 51: Driving pattern calculation unit 52: Operating pattern holding unit 53: Load calculation section 55: Computational Model Creation Section 60: Selection department 61: Selection result display section 62: Selection result storage section 70: Judgment section 71: Judgment result display area 80: Input area 81: Multi-axis machine model selection button 82: Mechanism Specifications Input Button 83: Input button for driving conditions 84: Selection button 85: Judgment button 86: Re-selection input button 87: Multi-axis machine model display area 88: Selection result display area D1-D6: Drive shafts M1-M6: Electric motor

Claims

1. A multi-axis machine model holding unit that holds information on multiple multi-axis machine models, each representing the configuration of multiple multi-axis machines, each comprising multiple drive units and multiple electric motors that drive each of the multiple drive units, A model selection input unit that accepts a selection input for selecting one multi-axis machine model from the aforementioned multiple multi-axis machine models, For the multi-axis machine model selected by the aforementioned selection input, a mechanism specification input unit accepts input of mechanism specifications, For the multi-axis machine model selected by the aforementioned selection input, there is an operating condition input unit that accepts input of operating conditions, A calculation model creation unit creates a calculation model based on the multi-axis machine model selected by the selection input and the mechanism specifications received by the mechanism specifications input unit, A calculation unit calculates the operation pattern of the drive unit based on the calculation model created by the calculation model creation unit and the operation conditions received by the operation condition input unit, and calculates the load pattern of the drive unit using the operation pattern, A selection unit includes: a motor database that stores characteristic information for multiple motors, including model identification information, physical model information, and torque-speed characteristic data representing the output torque characteristics for each motor's rotational speed; a selection unit that, based on the operating pattern and load pattern calculated by the calculation unit, identifies the operating speed range and load torque in that operating speed range for each drive unit, determines the capacity conditions required in that operating speed range; searches for a motor having torque-speed characteristics that satisfy the capacity conditions in the operating speed range by referring to the torque-speed characteristic data included in the characteristic information stored in the motor database; searches for a motor having characteristic information that matches the operating pattern and load pattern calculated by the calculation unit; selects multiple motors to drive each of the multiple drive units of the selected multi-axis machine model; and generates the model identification information for the selected motors as a selection result. The selection unit selects a plurality of electric motors to drive each of the plurality of drive units by sequentially selecting electric motors from the electric motor database to drive the drive units on the machine end side of the multi-axis machine model, The calculation model creation unit is a motor selection device that, when the selection unit selects a motor, obtains the physical model of the motor from the motor database and supplements it with the calculation model.

2. The motor selection device according to claim 1, wherein the selection unit selects a motor from the motor database that matches the operating pattern and load pattern calculated by the calculation unit according to predetermined priority conditions.

3. The motor selection device according to claim 2, wherein the predetermined priority condition is that the smaller the size, the higher the priority.

4. The motor selection device according to claim 1, further comprising a selection result display unit that displays the model identification information of the motor selected by the selection unit.

5. A selection result storage unit that stores the selection results of multiple electric motors selected by the selection unit, The motor selection device according to claim 1, further comprising: a determination unit that determines whether the selection result stored in the selection result storage unit is suitable for a new input to at least one of the mechanism specifications input unit and the operating condition input unit.

6. The calculation model creation unit, based on new inputs to at least one of the mechanism specifications input unit and the operating conditions input unit, newly calculates a calculation model in which the physical model of the electric motor corresponding to the selection result stored in the selection result storage unit is supplemented to the multi-axis machine model. The calculation unit newly calculates the operating pattern and load pattern of the drive unit based on the newly calculated calculation model. The motor selection device according to claim 5, wherein the determination unit performs the determination using the newly calculated operating pattern and load pattern.

7. Includes a selection modification input unit that receives a selection modification command that commands a modification to the selection of at least one of the multiple electric motors selected by the selection unit, The motor selection device according to claim 1, wherein the selection unit re-selects a motor from the motor database that is suitable for the operating pattern and load pattern calculated by the calculation unit based on the selection correction command received by the selection correction input unit.

8. The calculation model creation unit creates a new calculation model by supplementing the multi-axis machine model with the physical model of the motor that is not subject to modification and the physical model of the motor that has been re-selected by the selection unit. The calculation unit newly calculates the operating pattern and load pattern of the drive unit based on the newly created calculation model. The motor selection device according to claim 7, wherein the selection unit re-selects a motor from the motor database that is suitable for the newly calculated operating pattern and load pattern.

9. The motor selection device according to claim 8, wherein the selection unit determines whether the motors not subject to modification are compatible with the newly calculated operating pattern and load pattern.

10. A motor selection program that incorporates a group of steps to operate a computer as a motor selection device according to any one of claims 1 to 9.

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