Servo tailstock control system and method

Abstract

A servo tailstock control system and method. When the control unit receives the first processing file currently used to process the workpiece from the input unit, it compares the first processing file with the database. When the first processing file is the same as the at least one processing file in the database. According to the relative relationship between the tailstock motor and the spindle motor in the at least one processing gear, a tailstock motor sensing signal transmitted from the sensor, a tailstock motor sensing signal transmitted from the tailstock motor at the moment The signal is compared with the current spindle motor signal from the spindle motor. The control unit then transmits the tailstock motor control command and the spindle motor control command respectively according to the aforementioned comparison results to control the relative relationship between the tailstock and the workpiece.

Description

Technical Field

[0001] This invention relates to the field of machine tool equipment technology, and in particular to a servo tailstock control system and a servo tailstock control method. Prior Technology

[0002] In the machine tool industry, when machining special workpieces, such as precision cutting and drilling to produce various finished parts, a tailstock is often needed to hold the workpiece at its tail end to improve machining stability and quality. Traditionally, manual and hydraulic tailstocks are commonly used. However, manual tailstocks are labor-intensive, and hydraulic tailstocks are difficult to precisely control the tailstock thrust. Therefore, the application of servo tailstocks is gradually increasing.

[0003] During processing, the position of the tailstock needs to be adjusted accordingly depending on the size of the workpiece, and the tailstock motor needs to be repositioned to the appropriate position for different workpieces. Currently, the setting of the tailstock thrust force is mostly determined by the user (e.g., shaking the workpiece by hand to check if it is loose), but this method is too subjective and often results in problems with improper thrust force adjustment: 1. If the thrust force is too small, there is a risk that the workpiece may fall or even fly out. 2. If the thrust force is too large, there is a concern that the workpiece may deform or have excessive tolerances. Summary of the Invention

[0004] The purpose of this invention is to provide a servo tailstock control system and method, which can accurately control parameters such as position, speed, and thrust of the tailstock and spindle during the machining process, and help users dynamically adjust the tailstock thrust and position during the machining process.

[0005] To achieve the above objectives, the present invention provides a servo tailstock control system, comprising: an input unit for receiving a machining order, a tailstock, a tailstock motor coupled to the tailstock, a sensor coupled to the tailstock motor, a workpiece, and a spindle motor coupled to the workpiece. A storage unit includes a database containing at least one machining file used to determine the relative relationship between the tailstock motor and the spindle motor during machining. A control unit is coupled to the input unit, the storage unit, the tailstock motor, the sensor, and the spindle motor. The control unit receives a first machining file from the input unit for machining the workpiece and compares the first machining file with the database in the storage unit. When the first machining file matches the at least one machining file in the database, the control unit compares the relative relationship between the tailstock motor and the spindle motor in the at least one machining file with a tailstock motor sensing signal from the sensor, a tailstock motor signal from the tailstock motor, and a spindle motor signal from the spindle motor. Based on the comparison results, the control unit sends a tailstock motor control command and a spindle motor control command to the tailstock motor and the spindle motor, respectively, to control and adjust the relative relationship between the tailstock and the workpiece.

[0006] To achieve the above objectives, the present invention provides a servo tailstock control method for controlling the relative relationship between a tailstock and a workpiece, wherein a tailstock motor is coupled to the tailstock, a sensor is coupled to the tailstock motor, and a spindle motor is coupled to the workpiece. The control method includes: using a database in a storage unit containing at least one processing file for executing the relative relationship between the tailstock motor and the spindle motor during a processing program; a control unit coupled to an input unit, the storage unit, the tailstock motor, the sensor, and the spindle motor; when the control unit receives a first processing file from the input unit for processing the workpiece, and sets the second processing file accordingly... A processing file is compared with the database in the storage unit. When the first processing file is the same as at least one processing file in the database, the control unit compares the relative relationship between the tailstock motor and the spindle motor in the at least one processing file with the current tailstock motor sensing signal, the current tailstock motor signal, and the current spindle motor signal. The control unit then sends a tailstock motor control command and a spindle motor control command to the tailstock motor and the spindle motor respectively based on the comparison results, so as to control and adjust the relative relationship between the tailstock and the workpiece respectively.

[0007] Compared to prior art, the servo tailstock control system and method of the present invention offer the following main benefits: 1. Using spindle load rate as a data reference is more reliable than currently known methods. 2. With sufficient spindle load rate data for modeling, the system can automatically adjust the tailstock thrust according to the current machining situation, achieving Industry 4.0. 3. Achieving energy savings; excessive thrust increases energy consumption, leading to significant energy waste over long-term machining. The servo tailstock control system and method of this invention can automatically find the most suitable thrust for the current situation, reducing energy consumption. Simple Explanation of the Diagram

[0008] Figure 1 is a schematic diagram of the mechanical analysis of the servo tailstock. Figure 2 is a schematic diagram of the spindle load rate waveform corresponding to different tailstock thrusts when performing the same machining gear. Figure 3 is a schematic diagram of the servo tailstock control system in this case. Figure 4 is a flowchart of the dynamic adjustment of the servo tailstock thrust in this case. Figure 5 is a flowchart of the servo tailstock alarm process in this case. Implementation

[0009] The following details various embodiments of the present invention, illustrated in the accompanying drawings. Besides these detailed descriptions, the present invention can be widely implemented in other embodiments, and any easy substitutions, modifications, or equivalent changes to the described embodiments are included within the scope of the present invention and are subject to the claims. In the description of the specification, many specific details are provided to give the reader a more complete understanding of the present invention; however, the present invention may still be implemented even with some or all of these specific details omitted. Furthermore, well-known steps or elements are not described in the details to avoid unnecessarily limiting the present invention. Identical or similar elements in the drawings will be represented by the same or similar symbols. It is particularly important to note that the drawings are for illustrative purposes only and do not represent the actual size or number of elements; some details may not be fully drawn for the sake of simplicity.

[0010] First, please refer to Figure 1, which is a schematic diagram of the servo tailstock mechanical analysis. When performing precision cutting and drilling on workpiece 10, the tailstock 20 needs to hold the tail end of workpiece 10 to improve the stability and quality of the machining. Analyzing the workpiece 10 during machining assisted by the tailstock 20 (as shown in Figure 1), the tailstock 20 provides a tailstock thrust F to form a tailstock bearing force N, which counteracts the workpiece weight W and the forward turning force Fn of workpiece 10 itself. The quality of the tailstock thrust F adjustment is reflected in the spindle load rate. If the tailstock bearing force N can just offset the forward turning force Fn and the workpiece weight W, the spindle load rate will be relatively minimal, and the machining situation will be most stable.

[0011] Therefore, the key technology in this case is the adjustment of the servo tailstock thrust. We tried to use different tailstock thrusts F to perform the same machining mode and analyze the waveform of the spindle load rate. The system will dynamically adjust the tailstock thrust that is most suitable for the current machining situation based on the analysis results.

[0012] Please refer to Figure 2, which is a schematic diagram of the spindle load rate waveforms corresponding to different tailstock thrust forces when performing the same machining operation. In this case, under the same machining scenario, three different tailstock thrust forces F (thrust forces F1, F2 and F3) are used for machining, and the corresponding spindle load rate fluctuations are recorded. As shown in Figure 2, the spindle load rate corresponding to the first thrust force F1 has the largest difference between its peak and trough (Max Spindle load (1) and Min Spindle load (1)); while the spindle load rate corresponding to the third thrust force F3 has the smallest difference between its peak and trough (Max Spindle load (3) and Min Spindle load (3)). Therefore, under this machining scenario, machining with the third thrust force F3 is the most stable for the entire system.

[0013] Please refer to Figure 3, which is a schematic diagram of the servo tailstock control system of this case. In terms of implementation and application, the servo tailstock control system 100 of this case is applied in the field of machine tool equipment technology. The servo tailstock control system 100 includes: an input unit 110 for receiving the machining file of the workpiece. The input unit 110 is not limited to the input method and can be an input interface on the machining table or an external device (such as a laptop).

[0014] A tailstock 160 is coupled to a tailstock motor 140, which is used to control the position, displacement speed, and adjustment of the thrust of the tailstock 160; a sensor 180 is coupled to the tailstock motor 140, wherein the sensor 180 is an encoder used to sense the state of the tailstock motor 140.

[0015] After processing, a workpiece 170 becomes various finished parts; a spindle motor 150 is coupled to the workpiece 170 to drive the rotation and displacement of the workpiece 170.

[0016] A storage unit 120 includes a database. This storage unit 120 can be the built-in memory of the servo tailstock control system 100 controller or a cloud server, without limitation. The database contains at least one machining file used to execute the relative relationship between the tailstock motor 140 and the spindle motor 150 during the machining program. By attempting to execute the same machining file with different tailstock thrust forces F to perform waveform analysis of the spindle load rate, the system will dynamically adjust the tailstock thrust force most suitable for the current machining situation based on the analysis results. This adjustment is performed based on the database established (the establishment process will be explained later).

[0017] A control unit 130 is coupled to the input unit 110, the storage unit 120, the tailstock motor 140, the sensor 180 and the spindle motor 150; the control unit 130 receives a first processing file 111 for processing the workpiece 170 from the input unit 110 and compares the first processing file 111 with the database in the storage unit 120. When the first processing slot 111 is the same as at least one processing slot in the database, the control unit 130 compares the relative relationship between the tailstock motor 140 and the spindle motor 150 in the at least one processing slot in the database with a tailstock motor sensing signal 181 transmitted by the sensor 180 (which can determine the current position and speed of the tailstock 160), a tailstock motor signal 141 transmitted by the tailstock motor 140 (which can determine the current pushing force of the tailstock 160), and a spindle motor signal 151 transmitted by the spindle motor 150 (which can determine the current spindle load rate).

[0018] The control unit 130 then transmits a tailstock motor control command 142 and a spindle motor control command 152 to the tailstock motor 140 and the spindle motor 150 respectively, based on the aforementioned comparison results, to control and adjust the relative relationship between the tailstock 160 and the workpiece 170. The relative relationship between the tailstock 160 and the workpiece 170 includes relative force and / or relative speed and / or relative position.

[0019] In implementation, the tailstock motor signal 141 includes the current signal of the tailstock motor 140, and the spindle motor signal 151 includes the current signal of the spindle motor 150. The control unit 130 calculates the thrust of the tailstock 160 based on the current signal of the tailstock motor 140, calculates the load rate of the spindle motor 150 based on the current signal of the spindle motor 150, and calculates the position and speed of the tailstock 160 based on the tailstock motor sensing signal 181. In practical applications, the load rate is not limited to the spindle load rate; it can also be the axial load rate, tool load rate, etc., with different signal sampling depending on the usage requirements.

[0020] In practice, the control unit 130 compares the calculated pushing force of the tailstock 160, the load rate of the spindle motor 150, the position and speed of the tailstock 160 with the at least one machining file in the database, and transmits the tailstock motor control command 142 and the spindle motor control command 152 to the tailstock motor 140 and the spindle motor 150 respectively according to the comparison results, so as to control the relative relationship between the tailstock 160 and the workpiece 170 respectively.

[0021] Please refer to Figure 4, which is a flowchart of the dynamic adjustment of the servo tailstock thrust in this case. This case discloses a servo tailstock control method to control the relative relationship between the tailstock 160 and the workpiece 170. It is based on establishing a model of load rate (which can be spindle load rate, workpiece axial load rate, or tool load rate) and servo tailstock related parameters (such as thrust, position, or speed). During actual machining, the above model is imported to dynamically adjust the servo tailstock related parameters to optimize machining.

[0022] First, a database is established. The application is implemented as shown in Figures 1 and 2. Through adjustments to the tailstock 160 position, speed, and thrust, machining files are imported from the database for processing, and the spindle load rate waveform is recorded. The same machining file is then executed with different tailstock thrust pairs, and the current spindle load rate waveform is recorded and added to the machining file in the database. By executing the same machining file with different servo tailstock parameters (such as thrust, position, and speed), and recording the changes in load rate (spindle load rate, axial load rate, or tool load rate) under each parameter, the optimal servo tailstock parameters for executing the machining file are determined. At this stage, relevant models can be created for different machining files for future use, completing the establishment of the machining files in the database.

[0023] The servo tailstock control system 100 establishes a model of spindle load rate and tailstock thrust. When the workpiece 170 is actually processed, the control unit 130 receives the first processing sequence 111 currently used to process the workpiece 170 from the input unit 110 and compares the first processing sequence 111 with the database in the storage unit 120. When the first processing sequence 111 is the same as at least one processing sequence in the database, the control unit 130 compares the relative relationship between the tailstock motor 140 and the spindle motor 150 in at least one processing sequence in the database with a tailstock motor sensing signal 181 currently transmitted by the sensor 180, a tailstock motor signal 141 currently transmitted by the tailstock motor 140, and a spindle motor signal 151 currently transmitted by the spindle motor 150. The servo tailstock control system 100 dynamically adjusts the tailstock thrust according to the current spindle load rate. The servo tailstock control system 100 uses the control unit 130 to execute the optimal servo tailstock parameters for machining based on the machining files created in the database.

[0024] In practical application, the method in this case allows for waveform analysis and modeling of the tailstock 160's thrust force through monitoring the spindle load rate, enabling dynamic adjustment of the thrust force according to the machining situation. The position of the servo tailstock can be precisely set through the adjustment page, allowing for precise setting of the deceleration point, program end point, and initial point. During machining, the system can precisely control the position, speed, and thrust force of the tailstock 160 according to the user's settings, and provides adjustment functions to help users adjust the thrust force and position of the tailstock 160.

[0025] Please refer to Figure 5, which is the alarm flowchart of the servo tailstock in this case. In practical application, the servo tailstock control system 100 can also be equipped with a tailstock 160 abnormal alarm system (not shown in the figure) to assist users in troubleshooting. In practice, the alarm system can be a light display, sound display, screen display, etc., and its display methods and implementation methods are numerous and will not be described in detail here. Technically, the pushing force of the tailstock 160 can be analyzed and modeled by monitoring the spindle load rate, so that the pushing force can be dynamically adjusted according to the machining situation. The position of the tailstock 160 can be precisely set through the machining file adjustment page to set the deceleration point, program end point and start point. When machining starts, the tailstock 160 starts. If the servo tailstock misaligns (touches the workpiece prematurely) or fails to touch the workpiece, a relevant alarm is set to help users troubleshoot the problem and improve the safety of machining.

[0026] Among them, the top deviation alarm will sound if the actual clamping position of the tailstock 160 differs too much from the preset position. The workpiece contact alarm will sound if the tailstock 160 reaches the preset clamping position but does not contact the workpiece 170.

[0027] In addition, if the actual speed or thrust of the tailstock 160 deviates significantly from the set value, the system will issue an alarm. This alarm system helps users troubleshoot problems and increases the safety of servo tailstock-assisted machining.

[0028] The embodiments disclosed above are merely illustrative of the principles, features, and effects of the present invention and are not intended to limit the scope of implementation of the present invention. Any person skilled in the art may modify and alter the above embodiments without departing from the spirit and scope of the present invention. Any equivalent changes and modifications made using the content disclosed in this invention shall still be covered by the following patent application scope.

[0029] 10: Workpiece 20: Tail Seat F: Tailstock thrust N: Tailstock bearing capacity W: Workpiece weight Fn: Forward turning force 100: Servo Tailstock Control System 110: Input Unit 111: First processing section 120: Storage Unit 130: Control Unit 140: Tailstock motor 141: Tailstock motor signal 142: Tailstock motor control command 150: Spindle motor 151: Spindle motor signal 152: Spindle motor control command 160: Tail Seat 170: Workpiece 180: Sensor 181: Tailstock motor sensor signal

Claims

1. A servo tailstock control system, comprising: One input unit; One tail seat; A tailstock motor is coupled to the tailstock. A sensor is coupled to the tailstock motor; One workpiece; A spindle motor coupled to the workpiece; a storage unit including a database containing at least one machining file used to execute the relative relationship between the tailstock motor and the spindle motor during the machining program; a control unit coupled to the input unit, the storage unit, the tailstock motor, the sensor, and the spindle motor; the control unit receives a first machining file currently used for machining the workpiece from the input unit and compares the first machining file with the database in the storage unit; when the first machining file is the same as the at least one machining file in the database, the control unit compares the relative relationship between the tailstock motor and the spindle motor in the at least one machining file with a tailstock motor sensing signal currently transmitted by the sensor, a tailstock motor signal currently transmitted by the tailstock motor, and a spindle motor signal currently transmitted by the spindle motor; the control unit transmits a tailstock motor control command and a spindle motor control command to the tailstock motor and the spindle motor respectively based on the comparison results, so as to control and adjust the relative relationship between the tailstock and the workpiece respectively.

2. The servo tailstock control system as described in claim 1, wherein, The tailstock motor signal includes the current signal of the tailstock motor, and the spindle motor signal includes the current signal of the spindle motor; the control unit calculates the thrust of the tailstock based on the current signal of the tailstock motor, the control unit calculates the load rate of the spindle motor based on the current signal of the spindle motor, and the control unit calculates the position and speed of the tailstock based on the tailstock motor sensing signal.

3. The servo tailstock control system as described in claim 2, wherein, The control unit compares the calculated push force of the tailstock, the load rate of the spindle motor, the position and speed of the tailstock with the at least one machining file in the database, and transmits the tailstock motor control command and the spindle motor control command to the tailstock motor and the spindle motor respectively according to the comparison results, so as to control the relative relationship between the tailstock and the workpiece respectively.

4. The servo tailstock control system as described in claim 3, wherein, The relative relationship between the tailstock and the workpiece includes relative forces and / or relative velocities and / or relative positions.

5. The servo tailstock control system as described in claim 1, wherein, The sensor is an encoder.

6. A servo tailstock control method, applied to control the relative relationship between a tailstock and a workpiece, wherein a tailstock motor is coupled to the tailstock, a sensor is coupled to the tailstock motor, and a spindle motor is coupled to the workpiece, the control method comprising: storing at least one processing file in a database in a storage unit for executing the relative relationship between the tailstock motor and the spindle motor during a processing program; coupling an input unit, the storage unit, the tailstock motor, the sensor, and the spindle motor through a control unit; when the control unit receives a first processing file for processing the workpiece from the input unit, and compares the first processing file with the database in the storage unit; when the first processing file is the same as the at least one processing file in the database, the control unit compares the relative relationship between the tailstock motor and the spindle motor in the at least one processing file with a tailstock motor sensing signal from the sensor, a tailstock motor signal from the tailstock motor, and a spindle motor signal from the spindle motor; The control unit then transmits a tailstock motor control command and a spindle motor control command to the tailstock motor and the spindle motor respectively based on the aforementioned comparison results, so as to control and adjust the relative relationship between the tailstock and the workpiece respectively.

7. The servo tailstock control method as described in claim 6, wherein, The tailstock motor signal includes the current signal of the tailstock motor, and the spindle motor signal includes the current signal of the spindle motor; the control unit calculates the thrust of the tailstock based on the current signal of the tailstock motor, the control unit calculates the load rate of the spindle motor based on the current signal of the spindle motor, and the control unit calculates the position and speed of the tailstock based on the tailstock motor sensing signal.

8. The servo tailstock control method as described in claim 7, wherein, The control unit compares the calculated push force of the tailstock, the load rate of the spindle motor, the position and speed of the tailstock with the at least one machining file in the database, and transmits the tailstock motor control command and the spindle motor control command to the tailstock motor and the spindle motor respectively according to the comparison results, so as to control the relative relationship between the tailstock and the workpiece respectively.

9. The servo tailstock control method as described in claim 8, wherein, The relative relationship between the tailstock and the workpiece includes relative forces and / or relative velocities and / or relative positions.

10. The servo tailstock control method as described in claim 6, wherein, The sensor is an encoder.

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