Thread machining chip breaking control system and control method thereof

Abstract

The present invention discloses a thread machining chip breaking control system and a control method thereof, comprising a control module, a driver, a first swing axis and a second swing axis, wherein the control module comprises: a command receiving unit, a chip breaking unit and a path planning unit, wherein the command receiving unit is used to receive a machining command, a machining condition and a machine performance, and the command receiving unit calculates a movement command according to the machining command and the machining condition; the chip breaking unit receives the machining condition and the machine performance transmitted by the command receiving unit, and the chip breaking unit calculates a swing amplitude and a swing frequency according to the machining condition and the machine performance; the path planning unit receives the movement command calculated by the command receiving unit, and receives the swing amplitude and the swing frequency calculated by the chip breaking unit, and the path planning unit calculates a swing movement command according to the movement command, the swing amplitude and the swing frequency. The driver controls the first swing axis and the second swing axis simultaneously according to the swing movement command to perform a thread machining chip breaking process on the workpiece.

Description

Technical Field

[0001] The invention relates to the technical field of digital control, and in particular to a thread machining chip breaking control system and a control method thereof. Background Art

[0002] During the cutting process of a machine tool, the chips will wrap around the tool or workpiece, causing scratches on the workpiece or damage to the tool. Therefore, users will turn on the chip breaking function of the machine tool according to the actual processing situation, so as to avoid the generation of excessively long chips that affect the processing quality.

[0003] Existing thread machining chip breaking cutting technology usually encounters the following problems: (1) The user needs to set at least one set of parameters that best suit the machining conditions according to the actual machining parameters to perform the chip breaking cutting function. (2) Because the rigidity of each machine is different, even if the same machining conditions are set, the chip breaking effect may not be the same.

[0004] On the other hand, in the existing thread machining chip breaking process, the tool mostly breaks chips in a single direction, such as Figure 1A As shown, component symbol 100 is a workpiece, component symbol 102 is a tool, wherein the X direction is the cutting direction of the tool 102, and the Y direction is the vibration direction of the tool 102, so the tool 102 can only perform the thread machining chip breaking process in the X direction, but the disadvantage is that heat will be generated during the thread machining chip breaking process, and the thermal stress at high temperature will cause damage to the tool 102. Therefore, in order to avoid the situation where the contact area between the thread machining tool 102 and the workpiece 100 increases as the depth increases, resulting in tool breakage, most of the thread machining processes with equal area are used, such as Figure 1B As shown. Figure 1B In the figure, component symbol 1002 represents the thread on the workpiece 100, and the upper right corner of the figure represents the single-side feed equal area thread processing process, while the lower right corner of the figure represents the left-right feed equal area thread processing process. However, whether it is the single-side feed or the left-right feed equal area thread processing process, the user needs to set a large swing amplitude to obtain a good chip breaking effect, which easily causes problems such as poor workpiece thread quality and reduced surface finish. Summary of the invention

[0005] In order to improve the above problems, the main purpose of the present invention is to provide a thread machining chip breaking control system and a control method thereof, wherein the digital control device can automatically calculate the swing amplitude and swing frequency according to the current machining conditions and machine performance. The user of the machine only needs to turn on this function in the machining interval where this function is used, without setting any parameters, and without adjusting the chip breaking parameters according to each machining condition or different machines, which greatly improves the user's operational friendliness and accurately controls the quality of chip breaking.

[0006] Another object of the present invention is to provide a thread machining chip breaking control system and a control method thereof, which utilizes dual-axis simultaneous swinging to achieve a very stable chip breaking effect in equal-area thread machining (i.e., single-side feed and left-right feed). The very small swinging amount can also improve the quality of thread machining and provide good surface finish, and the machine's screw does not need to be swung back and forth with a large amplitude to reduce the wear on the screw.

[0007] According to the above purpose, the present invention discloses a thread machining chip breaking control system, including a control module, a driver, a first swing axis and a second swing axis, wherein the driver is connected to the control block and the first swing axis and the second swing axis respectively. The control module includes: a command receiving unit for receiving at least one machining command, at least one machining condition and at least one machine performance, and the command receiving unit calculates a movement command according to the machining command and the machining condition; a chip breaking unit receives the machining condition and the machine performance transmitted by the command receiving unit, and the chip breaking unit calculates the swing amplitude and the swing frequency according to the machining condition and the machine performance; and a path planning unit receives the movement command calculated by the command receiving unit, and receives the swing amplitude and the swing frequency calculated by the chip breaking unit, and the path planning unit calculates the swing movement command according to the movement command, the swing amplitude and the swing frequency. The driver is used to receive the swing movement command transmitted by the path planning unit. The control module controls the driver to simultaneously drive the first swing axis and the second swing axis according to the swing movement command to perform a thread machining chip breaking process on the workpiece.

[0008] In a preferred embodiment of the present invention, the chip breaking unit sets the swing frequency reference interval according to the machine performance, and the chip breaking unit compares the swing frequency reference interval with the swing frequency. When the swing frequency is not included in the swing frequency reference interval, the chip breaking unit recalculates according to the processing conditions and machine performance to obtain another swing frequency.

[0009] In a preferred embodiment of the present invention, the chip breaking unit sets an oscillation amplitude reference interval according to the machine performance, and the chip breaking unit compares the oscillation amplitude with the oscillation amplitude reference interval. When the oscillation amplitude is not included in the oscillation amplitude reference interval, the chip breaking unit recalculates according to the processing conditions and machine performance to obtain another oscillation amplitude.

[0010] In a preferred embodiment of the present invention, the control module further includes a memory unit for receiving and storing processing conditions and machine performance input by a user.

[0011] In a preferred embodiment of the present invention, the memory unit further stores at least one resonance frequency interval. When the oscillation frequency is included in the resonance frequency interval, the chip breaking unit recalculates the oscillation frequency according to the processing conditions and the machine performance to obtain another oscillation frequency.

[0012] In a preferred embodiment of the present invention, the first swing axis and the second swing axis are respectively connected to a swing unit, which includes a spindle and / or a feed axis, and the processing conditions include the rotation speed of the spindle, the feed speed of the feed axis and at least one workpiece feature of the workpiece, wherein the machine performance includes a speed loop gain and a speed loop integral time constant, and the workpiece feature includes the shape, size and / or material properties of the workpiece.

[0013] In a preferred embodiment of the present invention, the first swing axis and the second swing axis are connected to the main axis and / or the feed axis, and the driver drives the first swing axis and the second swing axis simultaneously according to the swing movement command.

[0014] In a preferred embodiment of the present invention, the chip breaking unit calculates the oscillation amplitude based on the speed, feed speed, speed loop gain and speed loop integral time constant, and the chip breaking unit calculates the oscillation frequency based on the rotational speed, feed speed, workpiece characteristics, speed loop gain and speed loop integral time constant.

[0015] In a preferred embodiment of the present invention, the machine performance also includes a position loop gain; the chip breaking unit further calculates the first swing amplitude based on the rotational speed, feed speed, speed loop gain, speed loop integral time constant and position loop gain, and the chip breaking unit further calculates the first swing frequency based on the rotational speed, feed speed, workpiece characteristics, speed loop gain, speed loop integral time constant and position loop gain.

[0016] In a preferred embodiment of the present invention, a first chip breaking amount is generated at a first time during the thread machining chip breaking process of the workpiece, and a second chip breaking amount is generated at a second time, and both the first chip breaking amount and the second chip breaking amount are included in the tolerance range.

[0017] In a preferred embodiment of the present invention, the workpiece undergoes a thread machining chip breaking process at a third time in the thread machining chip breaking process according to a third swing amplitude and a third swing frequency, and the workpiece undergoes a thread machining chip breaking process at a fourth time in the thread machining chip breaking process according to a fourth swing amplitude and a fourth swing frequency, and the third swing amplitude is greater than the fourth swing amplitude, and the third swing frequency is less than the fourth swing frequency, wherein the third processing distance moved by the swing unit at the third time is less than the fourth processing distance moved at the fourth time.

[0018] In a preferred embodiment of the present invention, the swing unit is configured to move along the first tooth surface of the workpiece during the thread machining chip breaking process.

[0019] In a preferred embodiment of the present invention, the swing unit is configured to move alternately along the first tooth surface and the second tooth surface of the workpiece during the thread machining chip breaking process.

[0020] In a preferred embodiment of the present invention, in a thread machining chip breaking control system, the path planning unit further includes: receiving a feedback value of a swing unit performing a thread machining chip breaking process on a workpiece; comparing the feedback value with a swing movement command to generate a feedback movement command; calculating a swing feedback movement command based on the feedback movement command, a second movement command, a second swing amplitude and a second swing frequency; and simultaneously driving the first swing axis and the second swing axis according to the swing feedback movement command to compensate for the thread machining chip breaking process on the workpiece, wherein the occurrence time point of the movement command is earlier than the occurrence time point of the second movement command.

[0021] In addition, the present invention further discloses a thread machining chip breaking control method, the steps of which include: starting a thread machining chip breaking process in a machining area; receiving a machining command, at least one machining condition and at least one machine performance; calculating a movement command based on the machining command and the machining condition; calculating a swing amplitude and a swing frequency based on the machining condition and the machine performance; calculating a swing movement command based on the movement command, the swing amplitude and the swing frequency; and controlling a driver according to the swing movement command to simultaneously drive a first swing axis and a second swing axis to perform a thread machining chip breaking process on the workpiece.

[0022] In a preferred embodiment of the present invention, the thread machining chip breaking control method further includes setting an oscillation frequency reference interval according to the machine performance, and comparing the oscillation frequency with the oscillation frequency reference interval. When the oscillation frequency is not included in the oscillation frequency reference interval, another oscillation frequency is recalculated according to the machining conditions and machine performance.

[0023] In a preferred embodiment of the present invention, the thread machining chip breaking control method further includes setting an oscillation amplitude reference interval according to the machine performance, and comparing the oscillation amplitude with the oscillation amplitude reference interval. When the oscillation amplitude is not included in the oscillation amplitude reference interval, it is recalculated according to the machining conditions and machine performance to obtain another oscillation amplitude.

[0024] In a preferred embodiment of the present invention, the processing conditions and machine performance can be input by the user or stored in the memory unit.

[0025] In a preferred embodiment of the present invention, the screw machining chip breaking control method further includes storing at least one resonance frequency range in a memory unit, and when the oscillation frequency is included in the resonance frequency range, recalculating the oscillation frequency according to the machining conditions and machine performance to obtain another oscillation frequency.

[0026] In a preferred embodiment of the present invention, the first swing axis and the second swing axis are connected to a swing unit, the swing unit includes a spindle and / or a feed axis, and the processing conditions include the spindle rotation speed, the feed speed of the feed axis and the workpiece characteristics of the workpiece, wherein the workpiece characteristics include the shape, size and / or at least one material property of the workpiece, and the machine performance includes the speed loop gain and the speed loop integral time constant.

[0027] In a preferred embodiment of the present invention, the oscillation amplitude is calculated based on the rotational speed, feed speed, speed loop gain and speed loop integral time constant, and the oscillation frequency is calculated based on the rotational speed, feed speed, workpiece characteristics, speed loop gain and speed loop integral time constant.

[0028] In a preferred embodiment of the present invention, the machine performance further includes a position loop gain, and the thread machining chip breaking control method further includes calculating a first oscillation amplitude based on the rotational speed, feed speed, speed loop gain, speed loop integral time constant and position loop gain, and further calculating a first oscillation frequency based on the rotational speed, feed speed, workpiece characteristics, speed loop gain, speed loop integral time constant and position loop gain.

[0029] In a preferred embodiment of the present invention, a first chip breaking amount is generated at a first time during the thread machining chip breaking process of the workpiece, and a second chip breaking amount is generated at a second time, and both the first chip breaking amount and the second chip breaking amount are included in the tolerance range.

[0030] In a preferred embodiment of the present invention, the workpiece undergoes a thread machining chip breaking process according to a third swing amplitude and a third swing frequency at a third time in the thread machining chip breaking process, and the workpiece undergoes a thread machining chip breaking process according to a fourth swing amplitude and a fourth swing frequency at a fourth time in the thread machining chip breaking process, and the third swing amplitude is greater than the fourth swing amplitude, and the third swing frequency is less than the fourth swing frequency, wherein a third processing distance moved by the swing unit at the third time is less than the fourth processing distance moved at the fourth time.

[0031] In a preferred embodiment of the present invention, the first swing axis and the second swing axis are connected to the main axis and / or the feed axis, and the driver drives the first swing axis and the second swing axis simultaneously according to the swing movement command.

[0032] In a preferred embodiment of the present invention, the thread machining chip breaking control method further includes the following steps: respectively receiving feedback values ​​of the first swing axis and the second swing axis for performing thread machining chip breaking process on the workpiece; comparing the feedback values ​​with the swing movement command to generate a feedback movement command; calculating the swing feedback movement command according to the feedback movement command, the second movement command, the second swing amplitude and the second swing frequency; and controlling the driver to simultaneously drive the first swing axis and the second swing axis to compensate for the thread machining chip breaking process on the workpiece according to the swing feedback movement command, wherein the occurrence time point of the movement command is earlier than the occurrence time point of the second movement command.

[0033] In a preferred embodiment of the present invention, the swing unit moves along the first tooth surface of the workpiece during the thread machining chip breaking process.

[0034] In a preferred embodiment of the present invention, the swing unit moves alternately along the first tooth surface and the second tooth surface of the workpiece during the thread machining chip breaking process.

[0035] Due to the adoption of the above technical scheme, the thread machining chip breaking control system and method of the present invention achieve the following technical effects: the swing amplitude and swing frequency can be automatically calculated according to the current processing conditions and machine performance. After the user turns on the chip breaking processing function, there is no need to set any parameters, nor is there any need to adjust the chip breaking parameters according to each processing condition or different machines, which greatly improves the user's operation friendliness and accurately controls the quality of chip breaking. The present invention utilizes dual-axis co-movement swing, and only a very small swing amount is required to achieve a very stable chip breaking effect under the condition of equal-area thread machining (i.e., single-side feed and left-right feed). The very small swing amount can also make the thread machining quality better and have a good surface finish, and the machine screw does not need to reduce the loss of the screw due to a large amplitude of back and forth swing. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1A It is a schematic diagram showing a single-axis vibration chip breaking process according to the prior art.

[0037] Figure 1B The present invention is a schematic diagram showing a chip breaking process of equal area thread machining according to the prior art.

[0038] Figure 2 It is a flow chart of the steps of a thread machining chip breaking control method according to an embodiment of the present invention.

[0039] Figure 3 It is a block diagram of a thread machining chip breaking control system according to an embodiment of the present invention.

[0040] Attached photos

[0041] 1: Thread machining chip breaking control system;

[0042] 2: Host computer;

[0043] 3: control module; 30: command receiving unit; 32: chip breaking unit; 34: path planning unit;

[0044] 36: memory unit;

[0045] 4: Driver;

[0046] 52: first swing axis; 54: second swing axis. DETAILED DESCRIPTION

[0047] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained under the premise of equivalent changes and modifications made by ordinary technicians in the field should belong to the scope of protection of the present invention.

[0048] First, please refer to Figure 2 and Figure 3 In the description Figure 2 At the same time, we also cooperate Figure 3 To illustrate, Figure 2 The invention discloses a flow chart showing the steps of a thread machining chip breaking control method and Figure 3 It is a schematic diagram showing a chip breaking control system for thread machining.

[0049] exist Figure 2 In the thread machining chip breaking control method, the steps include: Step S10: Start the thread machining chip breaking process in the machining interval. In this step, the user turns on the chip breaking machining function in the host computer 2 according to the actual machining process requirements. Step S12: The command receiving unit receives the machining command, at least one machining condition and at least one machine performance. In this step, the command receiving unit 30 in the control module 3 receives the machining command, at least one machining condition and at least one machine performance transmitted by the host computer 2, and the definitions of the machining command, machining condition and machine performance will be described in detail below. It is worth noting that the machine performance can be obtained by the host computer 2, and can also be built into the memory unit 36 ​​of the control module 3.

[0050] Then step S14: calculate the movement command according to the processing command and processing conditions. In this step, the command receiving unit 30 calculates the movement command according to the processing command and processing conditions transmitted by the host computer 2. Before the processing machine performs chip breaking processing on the workpiece (not shown in the figure), it is necessary to know the processing state of the workpiece through the processing command of the host computer 2, such as: cutting hole size or depth, etc. Step S16: calculate the swing amplitude and swing frequency according to at least one processing condition and at least one machine performance. In this step, the chip breaking unit 32 calculates the swing amplitude and swing frequency according to the processing conditions and machine performance transmitted by the host computer 2. In the present invention, the machine performance can be regarded as the rigidity of the processing machine, mainly including information such as speed loop gain, speed loop integral time constant and / or position loop gain. Step S18: calculate the swing movement command according to the movement command, swing amplitude and swing frequency. In this step, the command receiving unit 30 is used to transmit the movement command to the path planning unit 34, and the swing amplitude and swing frequency are transmitted to the path planning unit 34 by the chip breaking unit 32. Then, the path planning unit 34 calculates the swing movement command according to the movement command, the swing amplitude and the swing frequency.

[0051] Finally, in step S20: according to the swing movement command, the first swing axis 52 and the second swing axis 54 are driven to perform a threading and chip breaking process on the workpiece. In this step, the control module 3 can drive the driver 4 to control the first swing axis 52 and the second swing axis 54 to perform a threading and chip breaking process on the workpiece (not shown in the figure) at the same time according to the swing movement command calculated by the path planning unit 34 in step S18. The functions of the host computer 2, the control module 3, the command receiving unit 30, the chip breaking unit 32 and the path planning unit 34 are described in detail later.

[0052] Next, please refer to Figure 3 . Figure 3 This is a schematic diagram showing the chip breaking control system for thread machining. Figure 3 In the present invention, the thread machining chip breaking control system 1 at least comprises: a host computer 2, a control module 3, a driver 4, a first swing axis 52 and a second swing axis 54, wherein the control module 3 is connected to the host computer 2 and the driver 4 respectively, the driver 4 is connected to the first swing axis 52 and the second swing axis 54, and the driver 4 drives the first swing axis 52 and the second swing axis 54. In the present invention, the host computer 2 can be a processing machine (not shown in the figure) controller, a desktop computer, a laptop computer, a smart phone or a remote server, and the host computer 2 and the control module 3 are connected by wire or wirelessly.

[0053] The control module 3 at least includes a command receiving unit 30, a chip breaking unit 32, a path planning unit 34 and a memory unit 36, wherein the command receiving unit 30 receives the processing command, processing conditions and machine performance transmitted by the host computer 2, and the command receiving unit 30 calculates the movement command according to the processing command and the processing conditions, wherein the processing conditions include the rotation speed of the spindle and the feed speed of the feed axis, and transmits the calculated movement command to the path planning unit 34. In addition, the command receiving unit 30 transmits the spindle rotation speed, the feed speed of the feed axis, at least one workpiece feature of the workpiece and the machine performance in the processing conditions to the chip breaking unit 32. In the present invention, the processing command refers to the processing state of the workpiece, that is, what form the user wants to process the workpiece into. The workpiece features of the workpiece include the shape, size and / or material properties of the workpiece; the machine performance includes the speed loop gain, the speed loop integral time constant and / or the position loop gain.

[0054] The chip breaking unit 32 receives the spindle speed, feed speed of the feed shaft, at least one workpiece feature of the workpiece and machine performance in the processing conditions transmitted by the command receiving unit 30 to calculate the swing amplitude and swing frequency of the swing unit. Among them, the swing amplitude is calculated by the chip breaking unit 32 based on the spindle speed, feed speed of the feed shaft, speed loop gain and speed loop integral constant in the machine performance. In addition, the swing frequency is calculated by the chip breaking unit 32 based on the spindle speed, feed speed of the feed shaft, workpiece features and speed loop gain and speed loop integral time constant in the machine performance. It is worth noting that the workpiece features in the processing conditions are the workpiece features of the workpiece at each stage of the thread processing chip breaking process.

[0055] In another embodiment of the present invention, the chip breaking unit 32 can calculate the first swing amplitude according to the spindle speed, the feed speed of the feed axis, the speed loop gain, the speed loop integral time constant and the position loop gain, and calculate the first swing frequency according to the spindle speed, the feed speed of the feed axis, the workpiece characteristics, the speed loop gain, the speed loop integral time constant and the position loop gain. It is worth noting that the chip breaking unit 32 also takes into account the position loop gain in the machine performance to calculate the first swing amplitude and the first swing frequency, which is actually an optimization method, which can improve the stability and accuracy of the thread machining chip breaking process.

[0056] Next, the chip breaking unit 32 transmits the swing amplitude and the swing frequency calculated above to the path planning unit 34, and the path planning unit 34 calculates the swing movement command according to the movement command transmitted by the command receiving unit 30 and the swing amplitude and the swing frequency transmitted by the chip breaking unit 32. In another embodiment, the chip breaking unit 32 transmits the first swing amplitude and the first swing frequency to the path planning unit 34, and similarly, the path planning unit 34 calculates the first swing movement command according to the movement command transmitted by the command receiving unit 30 and the first swing amplitude and the first swing frequency transmitted by the chip breaking unit 32, so that the driver 4 receives the swing movement command (or the first swing movement command) transmitted by the path planning unit 34 in the control module 3, and controls the first swing axis 52 and the second swing axis 54 to perform a thread machining chip breaking process on the workpiece (not shown in the figure) according to the swing movement command (or the first swing movement command).

[0057] In an embodiment of the present invention, the chip breaking unit 32 mainly sets the swing frequency reference interval according to the machine performance (it can also be set according to the user). In another embodiment, the swing frequency reference interval can also be set by the user. Then, the chip breaking unit 32 compares the swing frequency reference interval with the swing frequency calculated previously. When the swing frequency is not included in the swing frequency reference interval, the chip breaking unit 32 will recalculate another swing frequency included in the swing frequency reference interval. For example, when the swing frequency (referred to as the swing frequency f1) calculated by the chip breaking unit 32 is less than the minimum value of the swing frequency reference interval (referred to as the swing frequency fA) or greater than the maximum value of the swing frequency reference interval (referred to as the swing frequency fB) (i.e., the swing frequency f1 does not fall into the swing frequency reference interval), the chip breaking unit 32 will not directly output the calculated swing frequency f1 to the path planning unit 34, but calculate another swing frequency (referred to as the swing frequency f2) included in the swing frequency reference interval according to the swing frequency fA and the swing frequency fB, and the chip breaking unit 32 will subsequently output the swing frequency f2 to the path planning unit 34.

[0058] On the other hand, the chip breaking unit 32 mainly sets the swing amplitude reference interval according to the machine performance, and in another embodiment, it can also be set by the user. The chip breaking unit 32 compares the previously calculated swing amplitude with the swing amplitude reference interval. When the swing amplitude is not included in the swing amplitude reference interval (i.e., the swing amplitude does not fall into the swing amplitude reference interval), the chip breaking unit 32 will recalculate another swing amplitude included in the swing amplitude reference interval. For example, when the swing amplitude (referred to as the swing amplitude h1) calculated by the chip breaking unit 32 is smaller than the minimum value (referred to as the swing amplitude hA) of the swing amplitude reference interval or larger than the maximum value (referred to as the swing amplitude hB) of the swing amplitude reference interval (i.e., the swing amplitude h1 does not fall within the swing amplitude reference interval), the chip breaking unit 32 will not directly output the calculated swing amplitude h1 to the path planning unit 34, but will calculate another swing amplitude (referred to as the swing amplitude h2) included in the swing amplitude reference interval based on the swing amplitude hA and the swing amplitude hB, and the chip breaking unit 32 will subsequently output the swing amplitude h2 to the path planning unit 34.

[0059] The path planning unit 34 calculates the swing movement command according to the movement command received from the command receiving unit 30 and the swing frequency and swing amplitude received from the chip breaking unit 32. The driver 4 controls the first swing axis 52 and the second swing axis 54 to perform the thread machining chip breaking process according to the swing movement command calculated by the path planning unit 34.

[0060] The first swing axis 52 and the second swing axis 54 are respectively connected to a swing unit (not shown in the figure), wherein the swing unit includes a main axis (not shown in the figure) and / or a feed axis (not shown in the figure). Specifically, the first swing axis 52 and the second swing axis 54 are connected to the main axis and / or the feed axis, so when the swing unit is a feed axis (corresponding to a tool or a workpiece according to the actual processing flow), the feed axis can swing in any two axes of the x, y or z axis. Wherein, the feed axis can swing in any two axes of the x, y or z axis according to the actual processing flow to perform chip breaking during the processing. For example, when the processing flow is linear chip breaking, the feed axis can swing in any two axes of the x, y or z axis for chip breaking. In another embodiment, when the processing flow is an oblique line or an arc, the feed axis can swing in any two axes of the x, y or z axis to perform a thread processing chip breaking process. In other words, the first swing axis 52 and the second swing axis 54 can be any two axes of the x, y or z axis.

[0061] In another embodiment, when the swing unit is a spindle (corresponding to a tool or workpiece according to the actual processing flow), the spindle can swing in the a, b or c axis. Wherein, the spindle can swing in the a, b or c axis according to the actual processing flow for chip breaking. In one embodiment, when the processing flow is linear chip breaking, the spindle can swing in any two axes of the a, b or c axis for chip breaking; in another embodiment, when the processing flow is an oblique line or an arc, the spindle can swing in any two axes of the a, b or c axis for thread machining chip breaking process. In other words, the first swing axis 52 and the second swing axis 54 can be any two axes of the a, b or c axis. In another embodiment, when the swing unit is a feed axis and a spindle (corresponding to a tool or workpiece according to the actual processing flow), the feed axis can swing in any axis of the x, y or z axis and the spindle can swing in any axis of the a, b or c axis for chip breaking process. In other words, the first swing axis 52 may be any one of the x-axis, y-axis, or z-axis, and the second swing axis 54 may be any one of the a-axis, b-axis, or c-axis.

[0062] For example, the first swing axis 52 and the second swing axis 54 are respectively connected to the swing unit, and the swing unit moves along the first tooth surface of the workpiece to perform a thread machining chip breaking process. Specifically, the driver 4 controls the first swing axis 52 and the second swing axis 54 simultaneously according to the swing movement command to allow the swing unit to move along the first tooth surface of the workpiece (not shown in the figure), that is, the workpiece is subjected to a thread machining chip breaking process in a single-side feed manner. In another embodiment, the swing unit moves alternately along the first tooth surface and the second tooth surface of the workpiece to perform a thread machining chip breaking process, that is, the workpiece is subjected to a thread machining chip breaking process in a left-right feed manner. In yet another embodiment, after the first swing axis 52 and the second swing axis 54 allow the swing unit to move along the first tooth surface of the workpiece, the swing unit moves alternately along the first tooth surface and the second tooth surface of the workpiece, that is, the workpiece is first subjected to a thread machining chip breaking process in a single-side feed manner, and then subjected to a thread machining chip breaking process in a left-right feed manner.

[0063] In the present embodiment, the control module 3 further includes a memory unit 36 ​​for storing the processing conditions and machine performance input by the user or the host computer 2, and the swing frequency reference interval, swing amplitude reference interval and tolerance interval set by the chip breaking unit 32 according to the machine performance. In addition, the memory unit 36 ​​also stores a resonance frequency interval. When the swing frequency (referred to as the swing frequency f3) calculated by the chip breaking unit 32 is included in the default resonance frequency interval (i.e., the swing frequency f3 falls into the resonance frequency interval), it means that the vibration frequency generated by the swing unit during the thread machining chip breaking process will resonate with the machine (not shown in the figure), which will cause the thread machining chip breaking process to be unable to proceed smoothly, and it is also easy for the machine (not shown in the figure) and related parts to be damaged due to resonance. At this time, the chip breaking unit 32 will not directly output the calculated swing frequency f3 to the path planning unit 34, but avoid all frequencies in the resonance frequency interval to recalculate the swing frequency f4, and the subsequent chip breaking unit 32 will output the swing frequency f4 to the path planning unit 34.

[0064] In one embodiment of the present invention, a chip breaking amount is generated during the process of thread machining chip breaking process on the workpiece. When the driver 4 drives the first swing axis 52 and the second swing axis 54 to perform the thread machining chip breaking process on the workpiece according to the swing movement command, if the generated chip breaking amount is included in the tolerance interval, it means that the swing frequency and swing amplitude calculated by the chip breaking unit 32 can stably break the chips. If the chip breaking amount is not included in the tolerance interval, the user can decide whether the chip breaking unit 32 needs to recalculate the swing frequency and swing amplitude according to the actual processing situation, so that the chip breaking amount generated by the thread machining chip breaking process performed in different unit times should be included in the tolerance interval. In an embodiment of the present invention, the chip breaking amount can be weight or volume. For example, the workpiece will generate a first chip breaking amount at the first time in the thread machining chip breaking process, and a second chip breaking amount will be generated at the second time. When the weight or volume of the first chip breaking amount and the second chip breaking amount are both included in the tolerance interval, it means that the chip breaking effect of the current machine is stable.

[0065] In one embodiment, as the processing time of the workpiece is different, the swing frequency and the swing amplitude will also be adjusted accordingly. Taking the workpiece as a rod mounted on the spindle, and the swing unit as a tool mounted on the feed shaft as an example, in the thread machining chip breaking process, the tool will process from the outer diameter surface of the rod to the center of the rod. When the tool is at the third time (for example, the rod diameter is 50mm), the rod will be threaded according to the third swing amplitude and the third swing frequency. When the tool is at the fourth time (for example, the rod diameter is 40mm), the rod will be threaded according to the fourth swing amplitude and the fourth swing frequency. The third swing amplitude is greater than the fourth swing amplitude, the third swing frequency is less than the fourth swing frequency, and the third processing distance moved by the tool at the third time is less than the fourth processing distance moved at the fourth time.

[0066] In addition, the present invention compensates for the first swing axis 52 and the second swing axis 54 in the thread machining chip breaking process of the workpiece. The path planning unit 34 is mainly used to receive the feedback value when the first swing axis 52 and the second swing axis 54 perform the thread machining chip breaking process on the workpiece, wherein the feedback value is generated by the motor encoder (not shown in the figure). Then, the path planning unit 34 compares the feedback value with the swing movement command previously calculated by the chip breaking unit 32 based on the swing amplitude and the swing frequency to obtain the feedback movement command; then, the path planning unit 34 calculates the swing feedback movement command based on the feedback movement command, the movement command calculated based on the processing command, the processing conditions and the machine performance, the swing amplitude and the swing frequency in the next unit time. It should be noted that the time point at which the movement command obtained in the next unit time is generated is later than the time point at which the command receiving unit 30 calculates the movement command based on the processing command when the user inputs the processing command, the processing conditions and the machine performance through the upper computer 2 in the command receiving unit 30 of the control module 3. Finally, the control module 3 controls the first swing axis 52 and the second swing axis 54 simultaneously according to the swing feedback movement command to perform chip breaking process compensation for the thread machining of the workpiece.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. At the same time, the above description should be understandable and implementable for those with ordinary knowledge in the relevant technical field. Therefore, other equivalent changes or modifications that do not deviate from the concepts disclosed in the present invention should be included in the scope of protection of the present invention.

Claims

1. A thread machining chip breaking control system, characterized in that: include: A control module, the control module comprising: a command receiving unit, for receiving a processing command, at least one processing condition and at least one machine performance, and the command receiving unit calculates a movement command according to the processing command and the processing condition; a chip breaking unit, receiving the processing condition and the machine performance transmitted by the command receiving unit, and the chip breaking unit calculates a swing amplitude and a swing frequency according to the processing condition and the machine performance; and a path planning unit, receiving the movement command calculated by the command receiving unit, and receiving the swing amplitude and the swing frequency calculated by the chip breaking unit, and the path planning unit calculates a swing movement command according to the movement command, the swing amplitude and the swing frequency; a driver connected to the control module and configured to receive the swing movement command transmitted by the path planning unit; and A first swing axis and a second swing axis are connected to the driver respectively, and the control module controls the driver to drive the first swing axis and the second swing axis simultaneously according to the swing movement command to perform a thread machining chip breaking process on a workpiece; The chip breaking unit sets a swing frequency reference interval according to the machine performance, and the chip breaking unit compares the swing frequency reference interval with the swing frequency. When the swing frequency is not included in the swing frequency reference interval, the chip breaking unit recalculates according to the processing conditions and the machine performance to obtain another swing frequency. The machine performance includes a speed loop gain, a speed loop integral time constant and / or a position loop gain.

2. The thread machining chip breaking control system according to claim 1, characterized in that: The chip breaking unit sets an oscillation amplitude reference interval according to the machine performance, and compares the oscillation amplitude with the oscillation amplitude reference interval. When the oscillation amplitude is not included in the oscillation amplitude reference interval, the chip breaking unit recalculates according to the processing conditions and the machine performance to obtain another oscillation amplitude.

3. The thread machining chip breaking control system according to claim 1, characterized in that: The control module further includes a memory unit for receiving and storing the processing conditions and the machine performance input by the user.

4. The thread machining chip breaking control system according to claim 3, characterized in that: The memory unit stores at least one resonance frequency range. When the oscillation frequency is included in the resonance frequency range, the chip breaking unit recalculates the oscillation frequency according to the processing conditions and the machine performance to obtain another oscillation frequency.

5. The thread machining chip breaking control system according to claim 1, characterized in that: The first swing axis and the second swing axis are respectively connected to a swing unit, and the swing unit includes a spindle and / or a feed axis; the processing conditions include a rotation speed of the spindle, a feed speed of the feed axis and at least one workpiece feature of the workpiece; The workpiece feature includes a shape, a size and / or at least one material property of the workpiece; the machine performance includes a speed loop gain and a speed loop integral time constant.

6. The thread machining chip breaking control system according to claim 5, characterized in that: The first swing axis and the second swing axis are connected to the main axis and / or the feed axis, and the driver drives the first swing axis and the second swing axis simultaneously according to the swing movement command.

7. The thread machining chip breaking control system according to claim 5, characterized in that: The chip breaking unit calculates the oscillation amplitude according to the rotational speed, the feed speed, the speed loop gain and the speed loop integral time constant, and the chip breaking unit calculates the oscillation frequency according to the rotational speed, the feed speed, the workpiece characteristics, the speed loop gain and the speed loop integral time constant.

8. The thread machining chip breaking control system according to claim 5, characterized in that: The machine performance also includes a position loop gain; the chip breaking unit also calculates a first swing amplitude based on the rotational speed, the feed speed, the speed loop gain, the speed loop integral time constant and the position loop gain, and the chip breaking unit further calculates a first swing frequency based on the rotational speed, the feed speed, the workpiece characteristics, the speed loop gain, the speed loop integral time constant and the position loop gain.

9. The thread machining chip breaking control system according to claim 1, characterized in that: The workpiece will generate a first chip breaking amount at a first time during the thread machining chip breaking process, and will generate a second chip breaking amount at a second time, and both the first chip breaking amount and the second chip breaking amount are included in a tolerance range.

10. The thread machining chip breaking control system according to claim 8, characterized in that: The workpiece undergoes the thread machining chip breaking process at a third time in the thread machining chip breaking process according to a third swing amplitude and a third swing frequency, and the workpiece undergoes the thread machining chip breaking process at a fourth time in the thread machining chip breaking process according to a fourth swing amplitude and a fourth swing frequency, and the third swing amplitude is greater than the fourth swing amplitude, and the third swing frequency is less than the fourth swing frequency, wherein a third processing distance moved by the swing unit at the third time is less than a fourth processing distance moved at the fourth time.

11. The thread machining chip breaking control system according to claim 5, characterized in that: The swing unit is configured to move along a first tooth surface of the workpiece during the thread machining chip breaking process.

12. The thread machining chip breaking control system according to claim 5 or 11, characterized in that: The swing unit is further configured to move alternately along a first tooth surface and a second tooth surface of the workpiece during the thread machining chip breaking process.

13. The thread machining chip breaking control system according to claim 5, characterized in that: The path planning unit is further configured to include: Receiving a feedback value of the chip breaking process of the thread machining performed by the swing unit on the workpiece; comparing the feedback value with the swing movement command to generate a feedback movement command; Calculate a swing feedback movement command according to the feedback movement command, a second movement command, a second swing amplitude and a second swing frequency; and The first swing axis and the second swing axis are controlled simultaneously according to the swing feedback movement command to perform the thread machining chip breaking process compensation on the workpiece, wherein the generation time point of the movement command is earlier than the generation time point of the second movement command.

14. A thread machining chip breaking control method, characterized in that: The steps include: Start a thread machining chip breaking process in a machining area; Receiving a processing command, at least one processing condition and at least one machine performance; Calculate a movement command according to the processing command and the processing condition; Calculate an oscillation amplitude and an oscillation frequency according to the processing conditions and the machine performance; Calculate a swing movement command according to the movement command, the swing amplitude and the swing frequency; and Control a driver according to the swing movement command to simultaneously drive a first swing axis and a second swing axis to perform the thread machining chip breaking process on a workpiece; Setting a swing frequency reference interval according to the machine performance, and comparing the swing frequency with the swing frequency reference interval, and when the swing frequency is not included in the swing frequency reference interval, recalculating another swing frequency according to the processing conditions and the machine performance; The machine performance includes a speed loop gain, a speed loop integral time constant and / or a position loop gain.

15. The thread machining chip breaking control method according to claim 14, characterized in that: The method further includes setting a swing amplitude reference interval according to the machine performance, and comparing the swing amplitude with the swing amplitude reference interval. When the swing amplitude is not included in the swing amplitude reference interval, another swing frequency is recalculated according to the processing conditions and the machine performance.

16. The thread machining chip breaking control method according to claim 14, characterized in that: The processing conditions and the machine performance can be input by the user or stored in a memory unit.

17. The thread machining chip breaking control method according to claim 16, characterized in that: The method further includes storing at least one resonance frequency range in the memory unit, and when the oscillation frequency is included in the resonance frequency range, recalculating the oscillation frequency according to the processing conditions and the machine performance to obtain another oscillation frequency.

18. The thread machining chip breaking control method according to claim 14, characterized in that: The first swing axis and the second swing axis are respectively connected to a swing unit, the swing unit includes a spindle and / or a feed axis, and the processing conditions include a rotation speed of the spindle, a feed speed of the feed axis and at least one workpiece feature of the workpiece; The workpiece feature includes a shape, a size and / or at least one material property of the workpiece; the machine performance includes a velocity loop gain and a velocity loop integral time constant.

19. The thread machining chip breaking control method according to claim 18, characterized in that: The swing amplitude is calculated based on the rotation speed, the feed speed, the speed loop gain and the speed loop integral time constant, and the swing frequency is calculated based on the rotation speed, the feed speed, the workpiece characteristics, the speed loop gain and the speed loop integral time constant.

20. The thread machining chip breaking control method according to claim 18, characterized in that: in, The machine performance also includes a position loop gain, and the thread machining chip breaking control method further includes calculating a first oscillation amplitude based on the rotational speed, the feed speed, the speed loop gain, the speed loop integral time constant and the position loop gain, and further calculating a first oscillation frequency based on the rotational speed, the feed speed, the workpiece feature, the speed loop gain, the speed loop integral time constant and the position loop gain.

21. The thread machining chip breaking control method according to claim 18, characterized in that: The workpiece will generate a first chip breaking amount at a first time during the thread machining chip breaking process, and will generate a second chip breaking amount at a second time, and both the first chip breaking amount and the second chip breaking amount are included in a tolerance range.

22. The thread machining chip breaking control method according to claim 21, characterized in that: The workpiece undergoes the thread machining chip breaking process at a third time in the thread machining chip breaking process according to a third swing amplitude and a third swing frequency, and the workpiece undergoes the thread machining chip breaking process at a fourth time in the thread machining chip breaking process according to a fourth swing amplitude and a fourth swing frequency, and the third swing amplitude is greater than the fourth swing amplitude, and the third swing frequency is less than the fourth swing frequency, wherein a third processing distance moved by the swing unit at the third time is less than a fourth processing distance moved at the fourth time.

23. The thread machining chip breaking control method according to claim 18, characterized in that: The first swing axis and the second swing axis are connected to the main axis and / or the feed axis, and the driver drives the first swing axis and the second swing axis simultaneously according to the swing movement command.

24. The thread machining chip breaking control method according to claim 14, characterized in that: These include: Respectively receiving a feedback value of the first swing axis and the second swing axis performing the thread machining chip breaking process on the workpiece; comparing the feedback value with the swing movement command to generate a feedback movement command; Calculate a swing feedback movement command according to the feedback movement command, a second movement command, a second swing amplitude and a second swing frequency; and The driver is controlled according to the swing feedback movement command to simultaneously drive the first swing axis and the second swing axis to perform the thread machining chip breaking process compensation on the workpiece, wherein the generation time point of the movement command is earlier than the generation time point of the second movement command.

25. The thread machining chip breaking control method according to claim 18, characterized in that: The swing unit moves along a first tooth surface of the workpiece during the thread machining chip breaking process.

26. The thread machining chip breaking control method according to claim 18 or 25, characterized in that: The swing unit moves alternately along a first tooth surface and a second tooth surface of the workpiece during the thread machining chip breaking process.

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