Machine tool

Abstract

To provide a machine tool that can reduce a workload of adjusting a parameter associated with switching a quadrant.SOLUTION: A control device of a machine tool of the present disclosure executes: a test operation executing process, and a parameter acquiring process, wherein: the test operation executing process executes a test operation that moves a movement object by controlling a slide device based on a control program; and executes multiple test operations by changing at least one of parameters, namely, a backlash acceleration amount, which is a parameter when switching a quadrant that inverts a moving direction of the movement object, and a backlash acceleration time; and the parameter acquiring process acquires a positional deviation between a command position, which is the position of a movement destination of a designated movement object based on the control program, and an actual position of the movement object for each of multiple test operations; and acquires at least one parameter from a test operation whose acquired positional deviation is smaller than that of other test operations as an adjusted parameter.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to quadrant switching in machine tools. [Background technology]

[0002] Conventionally, in a machine tool, a moving object such as a tool is slid along a slide axis to machine a workpiece. In addition, the direction of the sliding movement of the moving object may be reversed during machining. For example, when a tool is slid as a moving object to machine a workpiece into an arc shape, the sliding direction of the tool is reversed at the apex of the arc shape. This reversal operation may result in the formation of a so-called quadrant protrusion on the machined surface. Specifically, the frictional force generated in the device that slides the moving object acts in the opposite direction to the moving direction of the moving object. When the moving direction of the moving object is reversed, the generated frictional force causes a delay in starting the reversal, causing a delay in control, which results in an error in the response to a command. For example, immediately after the quadrant is switched, a quadrant protrusion occurs in which the trajectory of the moving object bulges slightly outward from the trajectory of the command. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-90946 Summary of the Invention [Problem to be solved by the invention]

[0004] In the machine tool of the above-mentioned Patent Document 1, the quadrant projection is suppressed by adjusting the backlash acceleration amount (set acceleration amount in the document) during reversal. However, parameters such as the backlash acceleration amount need to be adjusted for each machine tool depending on the device-specific conditions such as the weight of the tool and deterioration over time, and there is a risk that the burden of the adjustment work will increase.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a machine tool that can reduce the workload of adjusting parameters associated with quadrant switching. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, this specification discloses a machine tool comprising a sliding device which slides an object to be moved along each of a plurality of sliding axes, and a control device which controls the sliding device, wherein the control device executes a test operation which controls the sliding device based on a control program to move the object to be moved, and executes a plurality of test operations with at least one of a backlash acceleration amount and a backlash acceleration time which are parameters at the time of quadrant switching which reverses the moving direction of the object to be moved, changed, and a parameter acquisition process which acquires, for each of the plurality of test operations, a position deviation between a command position which is a destination position of the object to be moved which is specified based on the control program, and an actual position of the object to be moved, and acquires, among the plurality of test operations, the at least one parameter in the test operation in which the acquired position deviation is smaller than that of the other test operations, as an adjusted parameter. Effect of the Invention

[0007] According to the machine tool of the present disclosure, the control device executes a test operation to move an object to be moved based on a control program. At this time, the control device executes the test operation multiple times while changing at least one of the parameters of the backlash acceleration amount and the backlash acceleration time. The control device acquires, from among the multiple test operations executed, the parameters in the test operation in which the position deviation between the command position of the control program and the actual position is the smallest, as the adjusted parameters. This makes it possible to find parameters with less deviation from the command position, and by setting the found parameters, it becomes possible to reduce or eliminate the quadrant protrusion. This reduces the workload of the operator in adjusting the parameters. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a block diagram of a machine tool according to the present embodiment. [Diagram 2] FIG. 13 is a graph showing the relationship between the X coordinate and time in machining of an arc shape, in which different backlash acceleration amounts and backlash acceleration times are set. [Diagram 3] FIG. [Figure 4] 4 is a flowchart showing a parameter setting process. [Diagram 5] FIG. 13 is a schematic diagram showing a test operation that generates an inversion in the X-axis direction. [Figure 6] FIG. 13 is a schematic diagram showing a test operation that generates a reversal in the Z-axis direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the machine tool of the present disclosure will be described in detail with reference to the drawings. FIG. 1 shows a block diagram of a machine tool 10 according to this embodiment. As shown in FIG. 1, the machine tool 10 is, for example, a lathe, and includes a work spindle device 11, a turret device 12, an X-axis slide device 13, a Z-axis slide device 14, a robot 15, an operation panel 20, and a control device 22. The configuration of the machine tool 10 shown in FIG. 1 is an example. For example, the machine tool 10 may be a lathe including a plurality of work spindle devices 11 and turret devices 12, or may be a so-called multi-tasking machine including a tool spindle device in addition to a lathe. Therefore, the machine tool of the present disclosure is not limited to a lathe, and machine tools of various configurations such as a machining center, a milling machine, and a drilling machine can be used. In addition, in various machine tools, test operations of a backlash acceleration amount Vb and a backlash acceleration time Tb described later may be performed.

[0010] The workpiece spindle device 11 is equipped with a chuck mechanism (such as a chuck jaw or a collet chuck) that grips a workpiece, and rotates the gripped workpiece around the workpiece spindle. The turret device 12 is equipped with a tool rest to which a plurality of tools (turret tools such as cutting tools and rotary tools) can be attached, and a rotary drive mechanism that rotates the tool rest. The turret device 12 drives the rotary drive mechanism to rotate the tool rest and change the tool indexed to the work position, and performs machining on the workpiece gripped by the workpiece spindle device 11 using the tool indexed to the work position. The tool rest is not limited to a turret-type tool rest, and may be a comb-shaped tool rest or the like.

[0011] The X-axis slide device 13 and the Z-axis slide device 14 are devices that change the position of the tool rest (the tool at the work position). The Z-axis slide device 14 is a device that moves the turret device 12, for example, in the Z-axis direction (the direction approaching the work or the direction moving away from the work) parallel to the work spindle. The X-axis slide device 13 is a device that moves the turret device 12 in the X-axis direction perpendicular to the work spindle, i.e., in the direction perpendicular to the Z-axis direction. The X-axis and Z-axis are examples of the slide axis, the first slide axis, and the second slide axis of the present disclosure. The X-axis and Z-axis directions do not have to be orthogonal. The X-axis and Z-axis directions do not have to be orthogonal as long as they intersect. Therefore, the first slide axis and the second slide axis of the present disclosure are not limited to being orthogonal.

[0012] For example, machine tool 10 is equipped with a slant-type bed. Z-axis slide device 14 is equipped with a Z-axis guide rail that is disposed on the guide surface of the bed and extends in a direction parallel to the Z-axis direction, and a Z-axis slider that can slide on the Z-axis guide rail. Z-axis slide device 14 is equipped with a Z-axis servo motor 14A, and transmits the rotation output of Z-axis servo motor 14A to the Z-axis slider via a transmission mechanism (e.g., a ball screw mechanism), and moves the Z-axis slider in the Z-axis direction. Move it in the opposite direction.

[0013] Furthermore, Z-axis slide device 14 includes Z-axis encoder 14B that outputs encoder information such as the rotational position of Z-axis servo motor 14A. Control device 22 executes feedback control to control the rotational speed and the like of Z-axis servo motor 14A based on the encoder information (rotational position information and the like) of Z-axis encoder 14B. Control device 22 controls Z-axis servo motor 14A to move the Z-axis slider to an arbitrary position in the Z-axis direction.

[0014] Furthermore, X-axis slide device 13 includes an X-axis guide rail arranged on the Z-axis slider, and an X-axis slider that is slidable on the X-axis guide rail. The X-axis guide rail is arranged in a direction parallel to the X-axis direction, and holds the X-axis slider so that it can slide in the X-axis direction. X-axis slide device 13 includes an X-axis servo motor 13A, and transmits the rotation output of X-axis servo motor 13A to the X-axis slider via a transmission mechanism (e.g., a ball screw mechanism), moving the X-axis slider in the X-axis direction.

[0015] Furthermore, the X-axis slide device 13 is equipped with an X-axis encoder 13B that outputs encoder information of the X-axis servo motor 13A. The control device 22 executes feedback control to control the rotation speed and the like of the X-axis servo motor 13A based on the encoder information of the X-axis encoder 13B. The control device 22 controls the X-axis servo motor 13A to move the X-axis slider to an arbitrary position in the X-axis direction.

[0016] The turret device 12 is mounted on the X-axis slider. Therefore, the control device 22 can move the turret device 12 (the indexed tool) to any position in the X-axis direction and the Z-axis direction by controlling the X-axis slide device 13 and the Z-axis slide device 14. In addition, the X-axis encoder 13B and the Z-axis encoder 14B of this embodiment can output the position deviation (which can also be called the position tolerance) of each slider to the control device 22. As will be described later, the control device 22 executes parameter adjustment based on the position deviation acquired from the X-axis encoder 13B and the Z-axis encoder 14B. Note that the method of acquiring the position and position deviation of the X-axis slider and the Z-axis slider is not limited to the encoder. The control device 22 may acquire the slide position and position deviation of the X-axis slider and the Z-axis slider using other position detection devices such as a linear scale. Also, the configuration of the slide device described above is one example. For example, the machine tool 10 may be provided with a slide device that moves the tool rest in three mutually perpendicular axial directions of X, Y, and Z. Furthermore, the definition of the direction may be changed as appropriate depending on the configuration of the machine tool 10.

[0017] The robot 15 is, for example, a gantry-type workpiece transport device (which may also be called a loader). The robot 15 is equipped with, for example, a head having a gripping portion (such as a chuck jaw) that grips a workpiece. The robot 15 can move the head along a rail base provided on the machine tool 10 in directions parallel to the left-right, up-down, and front-rear directions of the machine tool 10. The robot 15 uses the gripping portion of the head to transfer the workpiece between, for example, an entrance device that carries in the workpiece, an exit device that carries out the workpiece, a measuring device that inspects the shape of the workpiece, a workpiece inversion device that inverts the workpiece, and the like (all not shown).

[0018] The operation panel 20 includes, for example, a touch panel 26 and a plurality of operation switches 27, and displays information about the machine tool 10 and accepts operational instructions. In particular, in this embodiment, the machine tool 10 uses the touch panel 26 to display a reception screen 61 (see FIG. 3), which will be described later. The operation panel 20 is an example of a user interface of the present disclosure. Note that the user interface of the present disclosure is not limited to a configuration including both a display device and an input device, such as the touch panel 26. For example, the user interface may include a liquid crystal device and physical switches for selecting items displayed on the liquid crystal device. The machine tool 10 also includes the operation panel 20. It is also possible to provide a user interface other than the above, for example a portable user interface such as a teaching pendant.

[0019] The control device 22 includes a numerical control device 31 and a PLC 41. The numerical control device 31 includes a CPU 33 and a storage device 34. The PLC 41 includes a CPU 43 and a storage device 44. The storage devices 34, 44 include, for example, a RAM, a ROM, a flash memory, and a HDD. The configuration of the storage devices 34, 44 is not limited to the above configuration, and may include an SSD instead of an HDD, an external storage device such as a USB memory, a storage medium such as a DVD-RAM, or a combination of these.

[0020] Further, the machine tool 10 includes a plurality of drive circuits 28 that connect the control device 22 with each of the above-mentioned devices (the workpiece spindle device 11, the turret device 12, the X-axis slide device 13, the Z-axis slide device 14, the robot 15, and the operation panel 20). The control device 22 is electrically connected to each device via the drive circuits 28, and is capable of controlling each device. For example, if the drive circuit 28 is connected to the X-axis servo motor 13A of the X-axis slide device 13 or the motor of the drive source of the robot 15, the drive circuit 28 is a driver circuit (servo amplifier) ​​that changes the power (such as three-phase AC current) supplied to each motor (such as a servo motor) based on an instruction signal (such as a movement amount, a movement destination position, a movement speed, a target torque, etc.) of the control device 22. For example, if the drive circuit 28 is connected to the operation panel 20, the drive circuit 28 is an amplifier circuit that performs amplification of a signal input from the operation panel 20.

[0021] Further, the storage device 34 stores a plurality of NC programs 35 for numerically controlling the operations of the work spindle device 11, the turret device 12, the X-axis slide device 13, the Z-axis slide device 14, the robot 15, etc. The numerical control device 31 executes the NC program 35 in the CPU 33, and outputs an instruction signal to the drive circuit 28 (driver circuit) according to the numerical command described in the NC program 35 to perform control. The drive circuit 28 (driver circuit) executes feedback control for changing the current of the three-phase AC based on, for example, encoder information of an encoder (such as the X-axis encoder 13B) attached to each servo motor (such as the X-axis servo motor 13A) and an instruction signal (speed command) from the control device 22, and notifies the numerical control device 31 of the completion of processing, etc. As a result, the control device 22 slides the tool rest (tool) of the turret device 12, the head of the robot 15, etc. along each axial direction to a desired position based on the numerical control by the numerical control device 31. The driving source for slidingly moving each device is not limited to a servo motor, and other driving sources such as a stepping motor or a linear motor can also be used.

[0022] The PLC 41 is a programmable logic controller. The storage device 44 stores a ladder program 45 for constructing a ladder circuit for processing various signals. The PLC 41 executes the ladder program 45 in the CPU 43, and executes, by sequence processing based on the ladder program 45, a process for outputting an output signal to various elements such as lamps, relays, and solenoids provided in the machine tool 10 to drive them, and a process for inputting an input signal from elements such as limit switches and sensors. The PLC 41 is also connected to the numerical control device 31 via, for example, a communication bus 40, and is capable of communicating with the numerical control device 31. The PLC 41 executes input and output of signals between the numerical control device 31 and the PLC 41 using a device 46 constructed based on the ladder program 45. The device 46 is, for example, a storage area constructed on the storage device 44 by executing the ladder program 45 in the CPU 43, and is a device for storing signal values ​​of external I / O (sensors, etc.) provided in the machine tool 10, a device for storing signal values ​​for communication with the numerical control device 31, a device for realizing a keep relay for storing set values, and the like. As a result, the PLC 41 relays signals between the external I / O of the machine tool 10 and the numerical control device 31 ( Performs input and output.

[0023] In addition to the NC program 35, the storage device 34 also stores a display setting program 36 and various other data (not shown) required for machining and test operations. The display setting program 36 executes a process for changing the display content of the touch panel 26 and inputting set values ​​on the touch panel 26. The display setting program 36 also includes a program for executing a display process of a reception screen 61 (described later) and a parameter setting process (see FIG. 4) for executing a test operation and setting parameters (backlash acceleration amount, backlash acceleration time).

[0024] (Backlash acceleration amount and backlash acceleration time) Next, the backlash acceleration amount and the backlash acceleration time will be described. In the following description, in order to avoid the description becoming complicated, a case will be described in which a tool (tool rest) is adopted as the moving object of the present disclosure. Note that the moving object of the present disclosure is not limited to the tool rest, and other moving devices such as the gripping part of the robot 15 can be adopted. As the moving object of the present disclosure, a device that slides on multiple axes and in which the direction of movement is reversed can be appropriately adopted. For example, when the work spindle device 11 is caused to slide on multiple axes, the work spindle device (work) can be adopted as the moving object.

[0025] As described above, machine tool 10 is equipped with X-axis slide device 13 and Z-axis slide device 14, so that the trajectory of the tool (tool rest) can be made two-dimensional, and the tool can be moved in an arc shape or the like. In other words, when a command to move in an arc shape or the like is given from control device 22 to drive circuit 28 (servo amplifier), the trajectory of the tool becomes an arc shape or the like on the XZ plane. When machining such an arc shape or the like, the movement direction may be reversed on the X-axis and Z-axis.

[0026] FIG. 2 shows, as an example, the relationship between the X coordinate in the X-axis direction and time when machining an arc shape. The vertical axis of FIG. 2 shows, for example, the X coordinate acquired from the X-axis encoder 13B when machining an arc shape. The horizontal axis shows time. A thick solid line graph 51 in FIG. 2 shows the X coordinate of the X-axis encoder 13B when the tool is moved in an arc shape, that is, when the tool is moved ideally without a delay due to reversal based on a command value. The tool trajectory is, for example, an arc shape that connects two points with different Z-axis coordinates and the same X-axis coordinate with a constant radius of curvature R.

[0027] In the machining shown in FIG. 2, the movement direction of the X-axis is reversed from the positive direction (upward direction in FIG. 2) to the negative direction (downward direction in FIG. 2) at the apex of the arc shape, i.e., quadrant switching occurs. The frictional force generated when the X-axis slide device 13 moves the X-axis slider along the X-axis direction by a transmission mechanism (e.g., a ball screw mechanism) acts in the opposite direction to the movement direction of the X-axis slider. When the movement direction of the X-axis slider is reversed, an error occurs with respect to the movement command due to this frictional force and backlash of the ball screw mechanism. Note that although FIG. 2 only illustrates the X-axis direction, the same applies to machining of an arc shape in the Z-axis direction.

[0028] Immediately after the quadrant is switched at the apex of the arc shape, the tool trajectory bulges outward from the commanded (ideal) trajectory shown in graph 51. This variation in trajectory causes a quadrant protrusion on the machined surface. For this reason, the control device 22 of this embodiment has a function of performing backlash acceleration to suppress the increase in the quadrant protrusion. For example, in order to suppress the increase in the quadrant protrusion due to the reversal of the sliding directions of the X-axis slide device 13 and the Z-axis slide device 14, the control device 22 performs a correction to add a backlash acceleration amount Vb (see FIG. 3) for a backlash acceleration time Tb (see FIG. 3) to the X-axis slide device 13 and the Z-axis slide device 14. When the inversion of the X-axis direction shown in FIG.

[0029] The backlash acceleration amount Vb is a correction amount added to a speed command for correction in order to hasten the reversal of the tool movement direction along the X-axis direction and the Z-axis direction. That is, the backlash acceleration amount Vb is a correction amount applied to the speed command transmitted from the control device 22 to the drive circuit 28 (servo amplifier) ​​connected to the X-axis servo motor 13A and the Z-axis servo motor 14A in order to eliminate or reduce a quadrant projection. The backlash acceleration time Tb is, for example, a time for performing the correction based on the backlash acceleration amount Vb. The control device 22 performs the correction based on the backlash acceleration amount Vb and the backlash acceleration time Tb on the speed control at the time of reversal of the drive circuit 28. The control device 22 adds a correction based on the backlash acceleration amount Vb and the backlash acceleration time Tb to the speed command for performing the reversal operation of the tool movement along the X-axis direction, for example, and outputs the corrected speed command to the drive circuit 28. The drive circuit 28 executes feedback control based on the corrected speed command. As a result, the reversal is accelerated, and the quadrant projection can be suppressed. Note that the control device 22 may adjust only one of the backlash acceleration amount Vb or the backlash acceleration time Tb without adjusting both the backlash acceleration amount Vb and the backlash acceleration time Tb.

[0030] 2 show the X coordinate when the control device 22 controls the X-axis servo motor 13A of the X-axis slide device 13 and the Z-axis servo motor 14A of the Z-axis slide device 14 with a command value (speed command) for machining the arc shape shown in graph 51. Graphs 52 and 53 show the case where different values ​​of backlash acceleration amount Vb and backlash acceleration time Tb are added. As shown in graphs 53 and 53, protrusions 55 of different shapes (for convenience of explanation, they are called quadrant protrusions) are formed on the trajectory.

[0031] The frictional force of the transmission mechanism generated during the slide movement varies depending on, for example, the viscosity of the lubricant, the wear state of each contact portion, etc. When the frictional force varies, the shape of the quadrant protrusion 55 also varies. In addition, as shown in graphs 52 and 53, depending on the set values ​​of the backlash acceleration amount Vb and the backlash acceleration time Tb, the trajectory becomes more outwardly bulging or inwardly recessed than the ideal trajectory shown in graph 51. If the backlash acceleration amount Vb is increased or the backlash acceleration time Tb is lengthened, the acceleration and acceleration time at the quadrant switching increase, and conversely, if the backlash acceleration amount Vb etc. is decreased, the acceleration etc. decrease. However, the frictional force etc. described above varies depending on the weight of the tool to be moved, the conditions specific to the device such as aging deterioration, the radius R, the feed rate V, etc. described later, and the operating state at the quadrant switching changes. For this reason, it is difficult to determine the backlash acceleration amount Vb and the backlash acceleration time Tb uniformly.

[0032] Therefore, before executing actual machining, the control device 22 executes multiple test operations with different values ​​of the backlash acceleration amount Vb and the backlash acceleration time Tb, and adopts (selects) the backlash acceleration amount Vb and the backlash acceleration time Tb that minimize the position deviation as the adjusted set values. This position deviation is the position deviation between a command position, which is the position of the tool movement destination specified based on the NC program 35 for the test operation, and the actual position of the tool acquired by the X-axis encoder 13B or the like. More specifically, it is the position deviation between the ideal trajectory of the graph 51 based on the command value shown in FIG. 2, for example, and the actual movement trajectory. This makes it possible to suppress the increase of the quadrant projection 55, and to perform machining that is closer to or coincides with the ideal circular arc shape.

[0033] (About the test operation) Fig. 3 shows a reception screen 61 for receiving a request to execute a test operation. For example, after the power supply of machine tool 10 is turned on and the system is started, control device 22 executes display setting program 36 in CPU 33 and displays an initial screen on touch panel 26. Control device 22 displays reception screen 61 based on a predetermined operation input (an instruction to display reception screen 61) to touch panel 26. As shown in Fig. 3, control device 22 displays reception field 63 and history information display field 64 on reception screen 61. When test operation start button 65 displayed in reception field 63 is touched, control device 22 starts a parameter setting process shown in Fig. 4 and executes the test operation.

[0034] Moreover, the control device 22 displays a radius input field 66 and a feed rate input field 67 in the reception field 63. In the test operation, the control device 22 executes, for example, the NC program 35 for the test operation, and executes an operation of moving the tool along a path having an arc shape. The control device 22 receives the value of the radius R of the path having an arc shape [mm] in the radius input field 66. Furthermore, the control device 22 receives the value of the feed rate [mm / min] for moving the tool based on the NC program 35 in the test operation in the feed rate input field 67. Note that the units of the above-mentioned values ​​are merely examples. For example, the unit of the radius R may be cm. Furthermore, for example, the feed rate V is not limited to the distance the tool advances in one minute [mm / min]. For example, the distance the tool advances per one rotation of the workpiece [mm / rev] may be adopted as the unit of the feed rate V. That is, the feed speed V may be, for example, the distance that the cutting tool advances per rotation of the workpiece in the case of a cutting tool (chip), or the distance that the cutting tool advances per rotation of the rotating tool in the case of a rotating tool such as a drill. The size and shape of the quadrant protrusion 55 vary depending on the radius R of the arc shape that moves the tool and the feed speed V. In addition, as described in the prior art document (JP Patent Publication No. 2022-90946), the backlash acceleration amount Vb and the backlash acceleration time Tb are correlated with the radius R and the feed speed V. For example, the prior art document describes that the faster the feed speed V is, the more the backlash acceleration amount Vb needs to be increased and the backlash acceleration time Tb needs to be reduced. In addition, it is described that the larger the radius R is, the more the backlash acceleration amount Vb needs to be reduced and the backlash acceleration time Tb needs to be increased. However, as described above, the optimal backlash acceleration amount Vb and backlash acceleration time Tb are affected by factors other than the radius R and the feed speed V (such as deterioration over time), and are therefore difficult to adjust.

[0035] Therefore, the control device 22 of this embodiment receives in advance the radius R and feed rate V to be used in the test operation, sets the received values ​​in the NC program 35 for the test operation, etc., and executes the test operation. This allows the user to set, for example, the radius R and feed rate V of the workpiece to be machined, or the average radius R and feed rate V of the workpiece to be machined, in the radius input field 66 and the feed rate input field 67, and adjust the backlash acceleration amount Vb and the backlash acceleration time Tb.

[0036] As shown in FIG. 3, the control device 22 displays axis selection buttons 68, 69 under the history information display field 64. The axis selection button 68 is a button for selecting the X-axis direction as the target to be adjusted (axis in which inversion occurs). The axis selection button 69 is a button for selecting the Z-axis direction as the target to be adjusted. The control device 22 can adjust and set the backlash acceleration amount Vb and the backlash acceleration time Tb in the X-axis direction and the Z-axis direction separately. When the test operation start button 65 is touched, the control device 22 adjusts the backlash acceleration amount Vb and the like for the axis direction selected by the axis selection buttons 68, 69. FIG. 3 shows a state in which the axis selection button 68 (X-axis direction) is selected. In the following description, a case where the backlash acceleration amount Vb and the backlash acceleration time Tb in the X-axis direction are adjusted will be described. The adjustment of the backlash acceleration amount Vb and the backlash acceleration time Tb in the Z-axis direction can also be performed in the same manner as in the X-axis direction.

[0037] When the test operation start button 65 in FIG. 3 is touched, the control device 22 starts the parameter The meter setting process is started. As shown in FIG. 4, the control device 22 first sets the radius R and the feed rate V in step (hereinafter simply referred to as S) 11. The control device 22 sets, for example, the radius R input in the radius input field 66 and the feed rate V input in the feed rate input field 67 in FIG. 3 to the corresponding code of the NC program 35 for executing the test operation. The code here is, for example, a code for specifying the start coordinate of the movement and the radius R to move the tool in an arc shape, or a code for specifying the feed rate V. Alternatively, when the control device 22 stores the environmental variables in the storage device 34 separately from the NC program 35 and sets the environmental variables to the variables in the program when the NC program 35 is executed, the control device 22 may set the values ​​input in the radius input field 66, etc. to the environmental variables corresponding to the radius R and the feed rate V. Therefore, the method of setting the radius R and the feed rate V for the test operation is not particularly limited. The control device 22 may also limit the range of values ​​that can be input in the radius input field 66 and the feed rate input field 67, the number of digits, etc. For example, the control device 22 may limit the range of radius R values ​​that can be input in the radius input field 66 and the range of feed speed V values ​​that can be input in the feed speed input field 67 to certain ranges. This makes it possible to prevent control that exceeds the operable range during the test operation described below, and to prevent errors from occurring during the test operation.

[0038] FIG. 5 shows a schematic diagram of a test operation that generates a reversal in the X-axis direction and adjusts the backlash acceleration amount Vb and the backlash acceleration time Tb in the X-axis direction. As shown in FIG. 5, the NC program 35 executed in the test operation is a program that executes a test operation (simulated machining operation) in which the tool 71 moves along a circular arc-shaped path of radius r, with points P1 and P2 of different Z coordinates in the Z-axis direction (left and right direction in FIG. 5) as both ends. The center O in the figure is the center of the diameter of the circular arc shape. In this machining, the movement direction in the X-axis direction is reversed at the apex of the circular arc shape. The points P1 and P2 are points of predetermined coordinates based on the machining reference surface (machining reference position) of the machine tool 10. The points P1 and P2 are determined based on values ​​previously set in the NC program 35, for example. The control device 22 may receive set values ​​from the user for the coordinates of the points P1 and P2. Thereby, for example, when the actual machining operation of the workpiece includes a process of machining the outer diameter into an arc shape, the coordinates of that process can be set. In S11 of Fig. 4, the control device 22 sets the radius R received in the radius input field 66 of the reception screen 61 as the radius r in the test operation (to the code described above), and sets the feed speed V received in the feed speed input field 67 as the feed speed when moving the tool 71 along the arc-shaped path.

[0039] After executing S11, the control device 22 sets initial values ​​for the backlash acceleration amount Vb and the backlash acceleration time Tb (S13). The initial values ​​are lower limit values ​​in the ranges of parameters to be tested in multiple test operations described below, and are, for example, the minimum value that can be set. After executing S13, the control device 22 executes a first test operation (S15). The control device 22 executes the NC program 35 for the test operation based on the radius R and feed rate V set in S11, and the backlash acceleration amount Vb and backlash acceleration time Tb set in S13, and moves the tool 71 in an arc shape (see the arrow in FIG. 5).

[0040] When the control device 22 ends the first test operation in S15, it acquires the position deviation and stores it in the storage device 34 (S17). For example, the control device 22 associates the values ​​of the backlash acceleration amount Vb and the backlash acceleration time Tb used in the test operation with the value of the position deviation and stores them in the storage device 34. The X-axis encoder 13B and the Z-axis encoder 14B in this embodiment are capable of calculating the position deviation during control based on, for example, a predetermined period or a predetermined command under the control of the control device 22, and outputting the calculated position deviation to the control device 22. For example, the control device 22 executes the test operation in S15, and acquires the position deviation during the test operation from the X-axis encoder 13B and the Z-axis encoder 14B. Note that the method of acquiring the position deviation is not limited to the above-mentioned method of calculating using the encoder. For example, the control device 22 may calculate the position deviation. The control device 22 acquires the X coordinate from the X-axis encoder 13B at predetermined time intervals during the test operation, and outputs the acquired multiple coordinates to the control device 22. The position deviation may be obtained from the difference between the X coordinate of the position and the X coordinate of the arc shape specified by the NC program 35.

[0041] Furthermore, in this embodiment, processing is performed by assuming that the position information of X-axis encoder 13B and Z-axis encoder 14B, i.e., the positions of each slider (the position of the tool post), is the position of the tool 71. However, the machine tool 10 may be provided with a sensor or the like for detecting the indexed position of the tool 71, and the position deviation may be obtained based on the position information of the sensor (such as the position of the cutting edge).

[0042] After executing S17, the control device 22 judges whether the current backlash acceleration amount Vb is equal to or greater than a predetermined maximum backlash acceleration amount Vmax (S19). This maximum backlash acceleration amount Vmax is an upper limit value in the range of the backlash acceleration amount Vb to be tested in the test operation, and may be, for example, a settable maximum value. If the backlash acceleration amount Vb is smaller than the maximum backlash acceleration amount Vmax (S19: NO), the control device 22 increases the backlash acceleration amount Vb by a predetermined increment amount Va (S21). After increasing the backlash acceleration amount Vb by the increment amount Va, the control device 22 executes the test operation using the increased backlash acceleration amount Vb (S15) and acquires the position deviation (S17). As a result, the control device 22 repeatedly executes the test operation (S15) by increasing the backlash acceleration amount Vb by an increment Va until the backlash acceleration amount Vb becomes equal to or greater than the maximum backlash acceleration amount Vmax (S19: NO) while fixing the backlash acceleration time Tb to the initial value (see the arrow in FIG. 5). For example, the control device 22 moves the tool 71 in an arc shape from point P1 to point P2 shown in FIG. 5, and then places the tool 71 at point P1 again and executes control using the changed backlash acceleration amount Vb. For this reason, the increment Va is an adjustment amount for increasing the backlash acceleration amount Vb for each test operation, and by setting a smaller value, the accuracy of adjusting the backlash acceleration amount Vb can be improved. The storage device 34 stores a new position deviation value for each test operation (S17).

[0043] When the backlash acceleration amount Vb becomes equal to or greater than the maximum backlash acceleration amount Vmax (S19: YES), the control device 22 sets the backlash acceleration amount Vb to an initial value (S23) and executes S25. In S25, the control device 22 judges whether the backlash acceleration time Tb is equal to or greater than the maximum backlash acceleration time Tmax. If the backlash acceleration time Tb is smaller than the maximum backlash acceleration time Tmax (S25: NO), the control device 22 increases the backlash acceleration time Tb by an increment Ta (S27) and executes the processes from S15 onward. As a result, the backlash acceleration time Tb after being increased by the increment Ta is used to repeatedly execute the test operation while increasing the backlash acceleration amount Vb by an increment Va. That is, the control device 22 executes a process of repeatedly executing a test operation while fixing the backlash acceleration time Tb and increasing the backlash acceleration amount Vb by the increment amount Va, and increases the backlash acceleration time Tb by the increment amount Ta at a time until the backlash acceleration time Tb becomes equal to or greater than the maximum backlash acceleration time Tmax. The test operation is executed by changing the backlash acceleration amount Vb and the backlash acceleration time Tb in a fine manner according to the magnitude of the increment amounts Va and Ta.

[0044] When the backlash acceleration time Tb becomes equal to or greater than the maximum backlash acceleration time Tmax (S25: YES), the control device 22 acquires the backlash acceleration amount Vb and the backlash acceleration time Tb associated with the smallest position deviation among the position deviations stored in the storage device 34 in S17, and sets them as the backlash acceleration amount Vb and the backlash acceleration time Tb to be used in machining (S29). That is, the control device 22 sets the backlash acceleration amount Vb and the backlash acceleration time Tb used in the test operation that has produced the smallest position deviation among the multiple test operations as parameters to be used in the subsequent machining operation of the actual workpiece (S29). This allows the backlash acceleration amount Vb and the backlash acceleration time Tb that produce the smallest position deviation to be used in the actual machining of the workpiece, making it possible to more reliably reduce or eliminate the quadrant protrusion 55. The control device 22 acquires the backlash acceleration amount Vb and the backlash acceleration time Tb associated with the smallest position deviation among the multiple test operations. For example, the control device 22 may set the backlash acceleration amount Vb resulting in the second smallest position deviation or the backlash acceleration amount Vb resulting in the third smallest position deviation as a parameter during machining. Therefore, the "test operation in which the acquired position deviation is smaller than other test operations among the multiple test operations" in the present disclosure is not limited to the test operation with the smallest position deviation, but may be any test operation with a smaller position deviation than other test operations as appropriate. In addition, when multiple test operations with the same position deviation occur, the control device 22 may adopt, for example, the backlash acceleration amount Vb or the backlash acceleration time Tb of the first test operation executed among the test operations with the same position deviation as a parameter after adjustment.

[0045] When the control device 22 executes S29, it updates the history information display field 64 shown in FIG. 3 (S31) and ends the process shown in FIG. 4. As shown in FIG. 3, the control device 22 displays information on the radius R, the feed rate V, the backlash acceleration amount Vb, the backlash acceleration time Tb, the position deviation, and the implementation date and time in the history information display field 64 in order from the left. The control device 22 displays information on the test operation performed this time as this information. The radius R is a value inputted into the radius input field 66 and used in the test operation. Similarly, the feed rate V is a value inputted into the feed rate input field 67. The backlash acceleration amount Vb and the backlash acceleration time Tb are values ​​in the test operation in which the position deviation is smallest, that is, values ​​after adjustment. The position deviation is the smallest value among the position deviations of multiple test operations. In other words, it is the position deviation when the test operation is performed by setting the backlash acceleration amount Vb and the backlash acceleration time Tb after adjustment. The implementation date and time is the date and time when the test operation start button 65 was pressed and the test operation started. The control device 22 displays this information in a single line in the history information display field 64. This allows the user to check the past adjustment results and the settings at that time. The user can check parameter changes caused by the tool 71 and changes due to deterioration over time. By checking the cycle of changes, etc., the user can determine the appropriate time to operate the test operation start button 65 to adjust the backlash acceleration amount Vb, etc.

[0046] When the test operation start button 65 is touched to execute a new test operation, the control device 22 displays the result at the top of the history information display field 64 and moves past history down one by one. Note that the control device 22 sequentially displays history that could not be displayed in response to an operation of the scroll button 73 displayed in the history information display field 64.

[0047] In the above description, the test operation for adjusting the backlash acceleration amount Vb and the backlash acceleration time Tb in the X-axis direction has been described, but the adjustment in the Z-axis direction can be performed in the same manner. When the test operation start button 65 is touched in a state in which the axis selection button 69 shown in FIG. 3 is touched and selected, the control device 22 executes the test operation in the Z-axis direction as in the X-axis direction. FIG. 6 shows a schematic diagram of a test operation for generating a reversal in the Z-axis direction and adjusting the backlash acceleration amount Vb and the backlash acceleration time Tb in the Z-axis direction. As shown in FIG. 6, the control device 22 moves the tool 71 in the X-axis direction while reversing it in the Z-axis direction, and moves the tool 71 along a path of a circular arc shape. The control device 22 executes the test operation by setting the radius R set in the radius input field 66 as the radius r and using the feed rate V set in the feed rate input field 67. In other words, the radius input field 66 and the feed rate input field 67 are input fields that accept the value of the radius R and the value of the feed rate V used in the test operation of the slide axis selected by the axis selection buttons 68 and 69. This allows adjustment in each axis direction to be performed separately. Also, similar to the X-axis direction, the backlash acceleration amount Vb and the backlash acceleration time Tb that can further reduce the quadrant protrusion 55 according to the tool 71, aging deterioration, the radius R, the feed rate V, etc. can be set as parameters in the Z-axis direction. Also, the radius R and the feed rate V according to the axis direction to be adjusted can be set and adjustment can be performed. The quadrant protrusion 55 can be reduced by using more optimal parameters as parameters used for machining in the Z-axis direction (such as machining the end face of an arc shape).

[0048] Incidentally, the correspondence between the terms in this embodiment and those described in the claims will be explained below. In the above embodiment, the X-axis slide device 13 and the Z-axis slide device 14 are examples of slide mounting devices. The tool 71 is an example of an object to be moved. The touch panel 26 is an example of a user interface. The NC program 35 is an example of a control program. S15, S21, and S27 are examples of a test operation execution process. S17 and S29 are examples of a parameter acquisition process. The X-axis and Z-axis are examples of a slide axis, a first slide axis, and a second slide axis.

[0049] As described above, the present embodiment provides the following effects. The control device 22 according to one aspect of the present application executes a test operation in which the X-axis slide device 13 and the Z-axis slide device 14 are controlled based on the NC program 35 to move the tool 71 (S15). The control device 22 executes a plurality of test operations in which the backlash acceleration amount Vb and the backlash acceleration time Tb are changed (S15, S21, S27). The control device 22 acquires the position deviation between the command position (command value of each motor), which is the position of the movement destination of the tool 71 designated based on the NC program 35, and the actual position (encoder information) of the tool 71 for each of the plurality of test operations (S17). The control device 22 sets the backlash acceleration amount Vb and the backlash acceleration time Tb in the test operation in which the acquired position deviation is the smallest among the plurality of test operations, as the adjusted parameters (S29). This makes it possible to find parameters with less deviation from the command position, and by setting the found parameters, it becomes possible to reduce or eliminate the quadrant protrusion 55 as a result. This reduces the workload of the operator in adjusting the parameters.

[0050] Furthermore, the contents of the present disclosure are not limited to the above-described embodiments, but can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. For example, in the above embodiment, both the backlash acceleration amount Vb and the backlash acceleration time Tb are adjusted, but only one of them may be adjusted. For example, the value of one of the parameters, the backlash acceleration amount Vb or the backlash acceleration time Tb, may be received from the user, and the other parameter may be increased to perform a test operation. The process contents executed by the NC program 35 for test operation in the above embodiment are only an example. As the NC program 35 for test operation, another NC program 35 in which quadrant switching occurs can be adopted. For example, the NC program 35 for test operation may be an NC program 35 for moving the tool 71 in a circular path on the XZ plane. In this case, the control device 22 can adjust parameters in both the X-axis direction and the Z-axis direction together. For example, when the test operation start button 65 is operated and the parameter setting process of FIG. 4 is started, the control device 22 moves the tool 71 in a circular path in S15. For example, the control device 22 acquires the position deviation in the X-axis direction in an arc where the X coordinate is reversed, and acquires the position deviation in the Z-axis direction in an arc where the Z coordinate is reversed. Then, the control device 22 may set the backlash acceleration amount Vb and the backlash acceleration time Tb of the test operation when the position deviation is minimized for each direction as the adjusted parameters. This allows the adjustment in two directions to be performed together in one parameter setting process. Furthermore, the control device 22 may accept only one of the radius R and the feed speed V as the value to be used in the test operation. Alternatively, the control device 22 may use preset values ​​as the values ​​of the radius R and the feed speed V to be used in the test operation, and may not accept values ​​from the user. Furthermore, the control device 22 may accept values ​​other than the radius R and the feed speed V as the values ​​to be used in the test operation. For example, the coordinates of points P1 and P2 may be accepted.

[0051] In the parameter setting process of FIG. 4 in the above embodiment, the test operation is performed using the preset initial value, maximum backlash acceleration amount Vmax, maximum backlash acceleration time Tmax, and increments Va and Ta, but the present invention is not limited to this. For example, the control device 22 may set the initial value, maximum backlash acceleration amount Vmax, maximum backlash acceleration time Tmax, and increments Va and Ta. At least one value of the backlash acceleration amount Vmax, the maximum backlash acceleration time Tmax, and the increments Va and Ta may be received from the user. Furthermore, the initial value, maximum backlash acceleration amount Vmax, maximum backlash acceleration time Tmax, and increments Va and Ta used in the test operation may be set to values ​​derived by machine learning from past test operations. In the above embodiment, the NC program 35 that executes numerical control is used as the control program of the present disclosure, but the present disclosure is not limited to this. Various types of programs capable of controlling the machine tool 10 can be used as the control program of the present disclosure. In the above embodiment, the tool rest (tool 71) of the turret device 12 is used as the moving object of the present application, but the present invention is not limited to this. For example, other moving objects provided in the machine tool 10, such as the gripping portion of the robot 15 or the chuck mechanism of the workpiece spindle device 11, may be used as the moving object. 3 are merely examples of the screen configuration, display items, display positions, etc. of the reception screen 61. For example, the reception section 63 and the history information display section 64 may be separate screens.

[0052] The contents of this disclosure are not limited to the dependent relationships described in the claims. For example, this specification also discloses the technical idea of ​​changing "the machine tool according to claim 4" in claim 5 to "the machine tool according to any one of claims 1 to 4." In addition, this specification also discloses the technical idea of ​​changing "the machine tool according to claim 4" in claim 6 to "the machine tool according to claim 4 or claim 5." [Explanation of symbols]

[0053] 10 machine tool, 13 X-axis slide device (slide device), 14 Z-axis slide device (slide device), 22 control device, 26 touch panel (user interface), 35 NC program (control program), 64 history information display field, 65 test operation start button, 66 radius input field, 67 feed speed input field, 71 tool (moving object), R radius, Tb backlash acceleration time, Vb backlash acceleration amount, V feed speed.

Claims

1. a slide device that slides an object along each of a plurality of slide axes; A control device for controlling the slide device; Equipped with The control device includes: a test operation execution process for executing a test operation to control the slide device based on a control program and move the moving object, and executing the test operation a plurality of times while changing at least one of a backlash acceleration amount and a backlash acceleration time, which are parameters at the time of quadrant switching to reverse the moving direction of the moving object; a parameter acquisition process for acquiring a position deviation between a command position, which is a destination position of the object to be moved, specified based on the control program, and an actual position of the object to be moved, for each of a plurality of test operations, and acquiring, as an adjusted parameter, at least one of the parameters in a test operation in which the acquired position deviation is smaller than those in other test operations among the plurality of test operations; A machine tool that performs the above.

2. The control device includes: The machine tool according to claim 1 , wherein in the parameter acquisition process, the at least one parameter in the test operation that resulted in the smallest position deviation among the multiple position deviations acquired is acquired as a post-adjustment parameter.

3. A user interface is further provided, The control device includes:

3. The machine tool according to claim 1 or claim 2, wherein in the test operation execution process, an operation is performed to move the object to be moved along an arc-shaped path, and before executing multiple test operations, a radius value of the arc-shaped path is received via the user interface, and multiple test operations are executed based on the received radius value and the control program.

4. The moving object is It is a tool, The control device includes:

4. The machine tool according to claim 3, further comprising: a feed rate value for moving the tool based on the control program during the test operation received via the user interface; and a plurality of test operations performed based on the received feed rate value and the control program.

5. The control device includes: displaying, on the user interface, a radius input field for inputting a value of the radius, a feed rate input field for inputting a value of the feed rate, a test operation start button for starting execution of the test operation multiple times, and a history information display field; When the test operation start button is operated, the test operation is executed a plurality of times based on the radius value input in the radius input field, the feed rate value input in the feed rate input field, and the control program, after the test operations are performed a plurality of times, the radius value input in the radius input field, the feed rate value input in the feed rate input field, the at least one parameter acquired as an adjusted parameter by performing the test operations a plurality of times, the position deviation when the test operations are performed by setting the at least one adjusted parameter, and the date and time when the test operations were started a plurality of times are displayed in the history information display field in association with each other.

5. The machine tool according to claim 4.

6. The slide device is The object to be moved can be slid along a first slide axis and a second slide axis intersecting the first slide axis, The control device includes:

5. The machine tool according to claim 4, wherein the test operation execution process and the parameter acquisition process are executable for each of the first slide axis and the second slide axis, and a user selects either the first slide axis or the second slide axis as a slide axis for which the test operation execution process and the parameter acquisition process are to be executed via the user interface, and a value of the radius and a value of the feed rate to be used in the test operation for the selected slide axis are accepted via the user interface.

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