Tool changing control method, device and readable storage medium

Abstract

This invention relates to the field of tool changing, specifically to a tool changing control method, device, and readable storage medium. The control method includes: confirming whether tool changing conditions are ready; after confirming that the tool changing conditions are ready, controlling a motor to rotate to perform a tool locking action; during the tool locking action, when feedback is received that the motor has reached the tool locking end position, controlling the motor to stop and performing tool release output control; when feedback is received that the tool release is in place, reading a pre-selected heavy tool signal; wherein, the pre-selected heavy tool signal is a predefined signal for tools prone to tool changing abnormalities; if a valid pre-selected heavy tool signal is read, controlling the motor to rotate at a heavy tool running speed slower than the normal running speed to perform the tool changing action; otherwise, controlling the motor to rotate at the normal running speed to perform the tool changing action. This invention, by pre-defining a pre-selected heavy tool signal for tools prone to tool changing abnormalities, can smoothly change all tools prone to tool changing abnormalities and quickly change normal tools, solving the problems of efficiency and coexistence of special tools.

Description

Technical Field

[0001] This invention relates to the field of tool changing, and more specifically to a tool changing control method, device, and readable storage medium. Background Technology

[0002] In CNC machine tool machining, to meet the machining requirements of various processes, a tool changer is usually used to change tools on the tool spindle. In the patent application CN201610969054.8, entitled "Servo Tool Magazine Tool Changing Control Method," during tool exchange, when the output current of the driver is detected to be greater than the reference current set in the parameters, it indicates a large external load, i.e., a heavy tool. Based on this condition, the software switches the motor speed to the heavy tool speed (low speed), thereby smoothly completing the tool exchange and reducing mechanical impact and the risk of tool drop.

[0003] However, in actual application conditions, we still have some problems: First, in industrial environments, the temperature difference between the four seasons and between the north and south is too great, which affects the mechanical load. As a result, when using light and small tools, the output current detected by the driver exceeds the heavy tool current value set in the parameters, so that all tool changing actions enter the heavy tool mode, reducing the tool changing efficiency. Second, for some relatively slender tools, the overall weight of the tool cannot meet the heavy tool load requirements. However, the tool is slender and the balance center of gravity of the tool is abnormal. When the tool arm rotates rapidly, the tool is prone to falling or tilting, which affects the tool changing.

[0004] In summary, due to changes in mechanical load caused by changes in ambient temperature or the tool changing requirements of special tools (such as relatively slender tools), the tool changing control method in the patent application number CN201610969054.8 becomes less than ideal, reducing the user experience. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a tool changing control method. By pre-defining a heavy tool pre-selection signal for tools that are prone to abnormal tool changing, it can smoothly change all tools that are prone to abnormal tool changing and quickly change normal tools, thus solving the problems of efficiency and coexistence of special tools.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is: a tool changing control method, comprising:

[0007] Confirm that the tool changing conditions are ready. After confirming that the tool changing conditions are ready, control the motor to rotate to achieve the tool locking action.

[0008] During the blade engaging action, when feedback is received that the motor has reached the blade engaging end position, the motor is stopped and the blade release output control is executed;

[0009] Upon receiving feedback that the tool has been released, the pre-selected heavy tool signal is read; wherein, the pre-selected heavy tool signal is a pre-defined signal for tools prone to abnormal tool changes;

[0010] If a valid heavy tool pre-selection signal is read, the control motor rotates at a heavy tool running speed that is slower than the normal running speed to perform the tool change action;

[0011] If a valid heavy tool pre-selection signal is not read, the control motor rotates at the normal operating speed to perform the tool change action.

[0012] Furthermore, the method also includes: during the process of controlling the motor to rotate at a normal operating speed to perform the tool changing action, if the output current of the driver that drives the motor to rotate is detected to be greater than a preset threshold, the motor is controlled to rotate at a heavy tool operating speed during the remaining tool changing stroke.

[0013] Furthermore, the conditions for tool changing are now met, specifically:

[0014] Tool positioning is ready, tool spindle height positioning is ready, tool spindle position positioning is ready.

[0015] Furthermore, the types of tools prone to abnormal tool changes include large tools, heavy tools, and long tools.

[0016] Furthermore, the method also includes:

[0017] During the tool change operation, when feedback on the tool change end position is received, the control motor stops and the tool clamping output control is executed;

[0018] During the tool clamping output control process, after receiving feedback on the tool clamping position, the tool magazine data table is updated and the motor is controlled to rotate to return to its original position.

[0019] Furthermore, during the process of controlling the motor to rotate to achieve the knife-locking action, and during the process of controlling the motor to rotate to return to the original position, the motor is controlled to rotate at a normal operating speed.

[0020] The present invention also relates to an apparatus comprising:

[0021] Memory, used to store computer programs;

[0022] A processor is configured to execute the computer program, which, when executed by the processor, implements the steps of the tool changing control method.

[0023] The present invention also relates to a readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the tool changing control method described above.

[0024] The present invention also relates to a computer program product, comprising a computer program that, when executed by a processor, implements the steps of the tool changing control method.

[0025] By adopting the above technical solution, the present invention predefines a heavy tool pre-selection signal for tools prone to tool changes, so that all special tools (heavy tools and non-heavy tools with abnormal shapes) have special tool flags. This allows for smooth tool changes at heavy tool running speed for all tools prone to tool changes without omission, while normal tools can still be changed quickly at the conventional running speed, thus solving the problem of coexistence of efficiency and special working conditions. Attached Figure Description

[0026] Figure 1 This is a flowchart of the tool changing control method of the present invention;

[0027] Figure 2 This is a schematic diagram of the tool changing device.

[0028] Figure 3 This is a timing diagram of the tool change operation under the conditions of invalid and valid heavy tool preselection signal;

[0029] In the diagram, 1 is the motor; 2 is the tool magazine; 3 is the tool arm; 4 is the tool spindle; and 5 is the lifting drive unit. Detailed Implementation

[0030] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0031] like Figure 1 As shown, a tool changing control method includes:

[0032] Step S1: Confirm whether the tool changing conditions are ready. After confirming that the tool changing conditions are ready, control motor 1 to rotate to realize the tool locking action.

[0033] Step S2: During the knife-holding action, when feedback is received that motor 1 has reached the knife-holding end position (knife arm 3 gripping the knife position), control motor 1 to stop and execute knife-release output control;

[0034] Step S3: Upon receiving feedback that the tool has been released, read the pre-selected heavy tool signal; wherein, the pre-selected heavy tool signal is a pre-defined signal for tools prone to tool change abnormalities.

[0035] Step S4: If a valid heavy tool pre-selection signal is read, control motor 1 to rotate at a heavy tool running speed slower than the normal running speed to perform the tool change action; if a valid heavy tool pre-selection signal is not read, control motor 1 to rotate at the normal running speed to perform the tool change action.

[0036] Step S5: During the tool changing action, when feedback of the tool changing end position (tool arm 3 completing tool exchange position) is received, control motor 1 to stop and execute tool clamping output control;

[0037] Step S6: During the tool clamping output control process, after receiving the tool clamping position feedback, the tool magazine data table is updated and the motor 1 is controlled to rotate to return to its original position.

[0038] It should be noted that the tool changing process is based on the tool changing device, which is specifically as follows: Figure 2 As shown, the device includes a motor 1, a cutter arm 3, and a lifting drive component 5. The lifting drive component 5 is connected to the cutter arm 3, and the motor 1 is connected to the lifting drive component 5 to drive the rotation of both the lifting drive component 5 and the cutter arm 3. The tool changing process is as follows:

[0039] The tool arm 3 rotates, and its two ends respectively hook onto the tools on the tool magazine 2 and the tool spindle 4 (tool hooking action) → The tool spindle 4 releases the tool (tool release), and the tool arm 3 pulls down the tool under the action of the lifting drive 5 → The tool arm 3 rotates to complete the tool exchange (tool change) → The tool arm 3 inserts the tool upward under the action of the lifting drive 5, and the tool spindle 4 clamps the tool (tool clamping).

[0040] When reading the heavy tool preselection signal, both the tools held in the tool magazine 2 and the tool spindle 4 need to be read. Regardless of whether the tool is in the tool magazine 2 or on the tool spindle 4, as long as there is a predefined heavy tool preselection signal, the heavy tool preselection signal is considered valid.

[0041] In a specific example, the normal operating speed is 2000 rpm or higher, which can be set as needed, but cannot exceed the maximum speed of the motor; the heavy-duty operating speed is 800 rpm or lower. Under normal circumstances, the tool arm 3 is already running very smoothly at 800 rpm.

[0042] Specifically, this embodiment predefines a heavy tool preselection signal for tools prone to tool changes, giving all special tools (heavy tools and non-heavy tools with abnormal shapes) a special tool flag. This allows for smooth tool changes at heavy tool running speed for all tools prone to tool changes without omission, while normal tools not predefined can still be changed quickly at the normal running speed, thus solving the problem of coexistence of efficiency and special working conditions.

[0043] In this embodiment, preferably, during the process of controlling motor 1 to rotate at normal operating speed to perform the tool changing action, if the output current of the driver that drives motor 1 to rotate is detected to be greater than a preset threshold, motor 1 is controlled to rotate at heavy tool operating speed during the remaining tool changing stroke.

[0044] Thus, even for heavy tools for which a pre-defined heavy tool selection signal was not pre-defined due to negligence or error, they can be identified during tool changing by detecting the current signal, and the heavy tool running speed can be used for tool changing, avoiding tool dropping or tool tilting and other tool changing anomalies. In addition, for tools that are prone to abnormal tool changing, they can be identified by pre-defining the heavy tool selection signal. Therefore, the preset threshold here can be set relatively high, thereby avoiding the situation mentioned in the background art where light or small tools are mistakenly changed at the heavy tool running speed due to temperature reasons.

[0045] In this embodiment, the tool change conditions being ready can be specifically defined as follows:

[0046] Tool positioning is ready, tool spindle 4 height positioning is ready, tool spindle 4 position positioning is ready.

[0047] In this embodiment, the types of tools prone to abnormal tool changes include large tools, heavy tools, and long tools.

[0048] In a specific example, a large tool refers to a tool with a diameter of 80 mm or more; a heavy tool refers to a tool weighing more than 4 kg; and a long tool refers to a tool with a length exceeding 300 mm and a diameter less than 12 mm. The definitions of various tools vary depending on the specific circumstances and are not limited to these examples.

[0049] In this embodiment, during the process of controlling the rotation of motor 1 to realize the knife-locking action, and during the process of controlling the rotation of motor 1 to return to the original position, motor 1 is controlled to rotate at a normal operating speed.

[0050] Thus, even for tools prone to abnormal tool changes, the tool changes are still relatively efficient because the tool arm 3 rotates at a heavy tool speed during the tool's rotation.

[0051] The solutions involved in the above embodiments will be described in detail below with reference to more detailed examples.

[0052] (a) Before the tool change begins, the CNC system (hereinafter referred to as "host computer") confirms whether the tool change conditions are ready (whether the tool is positioned, whether the height of the tool spindle 4 is positioned, and whether the position of the tool spindle 4 is positioned).

[0053] (b) After confirming that it is ready, the host computer sends a start signal for the first time. After the driver reads the first start signal, it controls the motor 1 to rotate to realize the knife-locking action.

[0054] (c) During the knife-locking action, the feedback position data of motor 1 is compared with the position setting parameter value of the driver, and a feedback signal is given to the host computer. After the host computer reads this signal, it disconnects the start signal and executes the knife-locking output control, and the knife-locking action is executed externally.

[0055] (d) After the host computer detects the feedback that the tool has been released, it sends a second start signal. When the driver reads the second start signal, it also reads the heavy tool preselection signal. When the heavy tool preselection signal is valid, the special tool flag is valid. At this time, the heavy tool running speed is put into the running variable in the software program. Otherwise, the normal running speed is put into the running variable in the software program.

[0056] (e) The host computer controls the motor 1 to rotate by the driver to realize the tool changing action. During the tool changing action, the host computer compares the position data fed back by the motor 1 with the position setting parameter value of the driver and gives a feedback signal to the host computer. After reading this signal, the host computer disconnects the start signal and executes the tool clamping control, and the tool clamping action is executed externally.

[0057] (f) After the host computer detects the tool clamping feedback, it updates the tool magazine data table and outputs the third start signal synchronously;

[0058] (g) When the driver reads the third start signal, it controls the motor 1 to rotate. When the driver reads the origin signal of the tool arm 3, it outputs a feedback signal to the host computer and performs precise positioning of the origin position simultaneously.

[0059] (h) After the host computer reads the feedback signal, it disconnects the start signal and executes the tool holder return to the horizontal position control of tool magazine 2. When the host computer detects that the tool holder horizontal position feedback is valid, the tool change ends.

[0060] Preferably, in step (e), when the heavy tool pre-selection signal is invalid, the tool exchange is initially performed at the normal speed (high speed). If motor 1 runs to the current detection window open position (motor 1 has an encoder, and the current detection window can be confirmed to be open based on the encoder feedback data), the driver detects the current value and compares it with the set heavy tool current value. If, before the current detection window closes, there is a detected current value greater than the set current value (heavy tool current value), the heavy tool running speed is added to the variable in the software, and the "remaining tool change stroke" controls motor 1 according to the heavy tool running speed; otherwise, the remaining tool change stroke controls motor 1 at the normal speed.

[0061] The above describes a complete tool change process. The heavy tool pre-selection process is handled during the second start signal of the tool change, because during the entire tool change process, when the tool arm is running, the tool arm is unloaded and there is no tool on it during the first and third start signals. The timing of each signal during the entire tool change process is explained as follows: Figure 3 As shown.

[0062] To facilitate understanding of the entire detailed tool changing process described above, the relevant content is explained as follows:

[0063] Start signal: This signal is used to trigger the operation of the cutter arm 3. When the constraints (cutter arm origin signal, cutter arm running sequence) are met, the driver reads that the start signal is valid and controls the motor 1 to rotate. Through the transmission chain, the driver then controls the operation of the cutter arm 3.

[0064] Heavy blade pre-selection signal: This signal is used to switch the running speed of the tool arm 3. In the control sequence, if the driver reads that the heavy blade pre-selection signal is valid, the driver control program switches to the heavy blade running speed (slow speed), controls the motor 1 to rotate, and slowly controls the running of the tool arm 3.

[0065] Current detection window: Due to special application conditions (when the tool is being exchanged, there is a tool pull-down → tool exchange → tool insertion), the current needs to be detected during the tool exchange process in order to best reflect the tool load. Therefore, a detection range is required. This range is determined by the running position of motor 1. This detection range is also called the "current detection window".

[0066] Heavy tool current value: The factory tests specify the weight of the tool (e.g., a 4 kg tool). When changing tools with this weight, the average current load value is recorded during multiple tool changes. This current value is set in the open parameters as a reference benchmark. This reference benchmark is called the "heavy tool current value".

[0067] Remaining tool change stroke: The current detection window represents a small interval during the tool exchange process. After this interval ends, the tool arm still needs to perform tool exchange and tool arm 3 insertion actions. The rotation angle of motor 1 from the current comparison result in the software to the tool insertion position is called the "remaining tool change stroke".

[0068] To facilitate understanding of the timing of each signal, the signal names and timing are explained as follows:

[0069] Signal Name Description:

[0070]

[0071] Node label description:

[0072] For ease of description, we define a high level (24V relative to 0V) as 1 and a low level (0V relative to 0V) as 0.

[0073] Label 1: Initial state. Before tool change, the following signal states are satisfied: tool engage signal is 1, tool clamping signal is 1, brake signal is 0, origin signal is 0, and tool release signal is 0.

[0074] Label 2: The host computer sets the start signal to 1. After the driver reads this signal, it controls motor 1 to rotate and executes the knife-locking action.

[0075] Label 3: When the brake signal status changes from 1 to 0, the host computer sets the start signal to 0, and the synchronous knife release control begins to execute;

[0076] Label 4: When the host computer reads the tool release signal as 1, the tool release is complete. The synchronous start signal is set to 1. After the drive reads this signal, it controls motor 1 to rotate and executes the tool change action.

[0077] Label 5: When using standard tools (the heavy tool pre-selection signal is invalid, i.e., this signal is 0), during tool change (tool exchange action), motor 1 runs at a higher speed;

[0078] Label 6: When the brake signal status changes from 1 to 0, the host computer sets the start signal to 0, and the synchronous clamping tool control begins to execute;

[0079] Label 7: The host computer's tool clamping position signal is 1. When the tool is clamped in place, a synchronous start signal is set. After the driver reads this signal, it controls motor 1 to rotate and executes the return to the origin action.

[0080] Label 8: The origin signal state changes from 1 to 0, the drive sets the brake signal to 0, and the host computer sets the start signal to 0;

[0081] Label 9: The heavy tool preselection signal is valid. The host computer sets the heavy tool preselection signal to 1.

[0082] Label 10: Same function as label 2;

[0083] Label 11: Same function as label 3;

[0084] Label 12: Same function as label 4;

[0085] Label 13: When the heavy tool preselection signal is valid (this signal is 1), during tool change (tool exchange action), motor 1 runs at a slower speed;

[0086] Label 14: Same function as label 6;

[0087] Number 15: Same function as number 7;

[0088] Number 16: Same function as number 8.

[0089] In the timing diagram, we can effectively solve the application under efficiency (without heavy tool pre-selection) and special working conditions (with heavy tool pre-selection signal). It perfectly solves the special working condition problem with minimal resources (only requiring the host computer to add one output point).

[0090] In addition, in the comparison timing, when there is a heavy tool pre-selection signal, we change the rotation speed of motor 1. The control logic is simple and clear, and has good portability in the control field. At least in the tool magazine field, if a variable speed device (servo driver, frequency converter, etc.) is configured, this control logic can be completed, solving the problem of coexistence of efficiency and special working conditions.

[0091] An apparatus comprising:

[0092] Memory, used to store computer programs;

[0093] A processor is configured to execute the computer program, which, when executed by the processor, implements the steps of the tool changing control method as described in the above embodiments.

[0094] A readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the tool changing control method as described in the above embodiments.

[0095] A computer program product includes a computer program that, when executed by a processor, implements the steps of the tool changing control method as described in the above embodiments.

[0096] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A tool changing control method, characterized in that, include: Confirm that the tool changing conditions are ready. After confirming that the tool changing conditions are ready, control the motor to rotate to achieve the tool locking action. During the blade engaging action, when feedback is received that the motor has reached the blade engaging end position, the motor is stopped and the blade release output control is executed; Upon receiving feedback that the tool has been released, the pre-selected heavy tool signal is read; wherein, the pre-selected heavy tool signal is a predefined signal for tools prone to abnormal tool changes; the types of tools prone to abnormal tool changes include large tools, heavy tools, and long tools; If a valid heavy tool pre-selection signal is read, the control motor rotates at a heavy tool running speed that is slower than the normal running speed to perform the tool change action; If a valid heavy tool pre-selection signal is not read, control the motor to rotate at the normal operating speed to perform the tool change action; During the tool changing operation, if the output current of the driver that drives the motor is detected to be greater than a preset threshold, the motor is controlled to rotate at a heavy tool speed during the remaining tool changing stroke. The preset threshold is greater than the current of the light and small tools after the temperature rises.

2. The tool changing control method according to claim 1, characterized in that, The tool change conditions are met, specifically: Tool positioning is ready, tool spindle height positioning is ready, tool spindle position positioning is ready.

3. The tool changing control method according to claim 1, characterized in that, The method also includes: During the tool change operation, when feedback on the tool change end position is received, the control motor stops and the tool clamping output control is executed; During the tool clamping output control process, after receiving feedback on the tool clamping position, the tool magazine data table is updated and the motor is controlled to rotate to return to its original position.

4. The tool changing control method according to claim 3, characterized in that, During the process of controlling the motor to rotate to achieve the knife-locking action, and during the process of controlling the motor to rotate to return to the original position, the motor is controlled to rotate at a normal operating speed.

5. A device, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program, which, when executed by the processor, implements the steps of the tool changing control method as described in any one of claims 1-4.

6. A readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the tool changing control method as described in any one of claims 1-4.

7. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the tool changing control method as described in any one of claims 1-4.

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