Linkage high-speed and high-efficiency vertical-horizontal conversion processing machine tool and design method

Abstract

The invention relates to a linkage high-speed and high-efficiency vertical-horizontal conversion machining tool and a design method, and belongs to the technical field of machining equipment. The linkage high-speed and high-efficiency vertical-horizontal conversion machining tool comprises a tool body frame, a rotary workbench, two machine tool spindles, two five-axis movement devices and a numerical control device. A rotary workbench is arranged in the center of the lathe bed frame; the machine tool spindle rotates around the Z-axis and the 45-degree B-axis rotation center, so that switching between the parallel state and the vertical state of the plane of the workbench is achieved. According to the invention, the main shaft moves along the X, Y and Z linear coordinate axes, the C rotating coordinate axis and the 45-degree B rotating coordinate axis, so that synchronous or asynchronous milling processing of workpieces to be processed by the double-side main shafts in a vertical or horizontal manner, such as processing of blisk and cylinder parts, can be met. Compared with a traditional five-axis machining machine tool, the five-axis machining machine tool has good structural rigidity, stress balance and thermal symmetry, the problem that the machining precision is reduced due to the fact that a workpiece is clamped for multiple times can be solved, and the machining efficiency is multiplied.

Description

Technical Field

[0001] The invention belongs to the technical field of processing equipment, and in particular relates to a linkage high-speed and high-efficiency vertical-horizontal conversion processing machine tool and a design method. Background Art

[0002] Five-axis linkage machining center, also known as five-axis machining center, is a kind of special machining equipment with high technology content and high precision. It is used to process complex curved surfaces and is a key means to solve the processing needs of impellers, blades, marine propellers, heavy generator rotors, turbine rotors, large diesel engine crankshafts, etc. At present, the five-axis linkage machining center on the market is generally divided into two types: vertical and horizontal. It is difficult to meet the requirement of one-time clamping of the workpiece to realize the whole process processing. Multiple clamping of the workpiece is likely to reduce the processing accuracy. And it is usually a single-spindle single five-axis machining center, which is difficult to efficiently process small batches of parts with long processing time. Summary of the invention

[0003] In view of the above problems, the present invention provides a linkage high-speed and efficient vertical-horizontal conversion processing machine tool and design method. It can realize two vertical-horizontal conversion spindles to process parts at the same time, solve the problem of reduced processing accuracy caused by multiple clamping of workpieces when processing parts with complex curved surfaces in conventional five-axis processing machines in the prior art, and can improve the production efficiency of parts processing and reduce processing costs while ensuring the quality of parts processing.

[0004] The present invention provides a linkage high-speed and high-efficiency vertical-horizontal conversion processing machine tool, comprising a bed frame, a rotary worktable, two groups of five-axis motion components and two groups of processing tools; The bed frame includes a processing platform and a track mounting frame; the track mounting frame includes a first side surface and a second side surface; the processing platform is arranged between the first side surface and the second side surface; Y-axis guide rails are arranged on the first side surface and the second side surface; the rotary table is arranged at the center of the processing platform; One set of five-axis motion components is disposed on the Y-axis guide rail on the first side; another set of five-axis motion components is disposed on the Y-axis guide rail on the second side; The five-axis motion assembly includes a Y-axis motion component, an X-axis guide, an X-axis motion component, a Z-axis guide, a Z-axis motion component, a C-axis rotating component, a B-axis rotating component, a machine tool spindle, and a processing tool; A C-axis rotating component is installed at the end of a Z-axis moving component, a B-axis rotating component is installed at the end of the C-axis rotating component at a first angle, a machine tool spindle is arranged at the end of the B-axis rotating component at a second angle, and a machining tool is arranged at the end of the machine tool spindle.

[0005] Optionally, the first angle and the second angle have the same degree.

[0006] Optionally, the first angle and the second angle are 45°.

[0007] Optionally, a mounting hole is provided inside the Y-axis moving component, an X-axis guide rail is provided based on the mounting hole, and the X-axis moving component is slidably provided on the X-axis guide rail through a slider and slides on the X-axis guide rail.

[0008] Optionally, a mounting hole is provided inside the X-axis component, a Z-axis guide rail is provided based on the mounting hole, and the Z-axis moving component is slidably provided on the Z-axis guide rail through a slider and slides on the Z-axis guide rail.

[0009] Optionally, a numerical control device is also included, and the bed frame is electrically connected to the numerical control device. The numerical control device is used to input and control numerical control programs and respectively control two groups of five-axis motion components for switching the parallel or vertical state of the machine tool spindle.

[0010] In another aspect, the present invention also discloses a design method for a linkage high-speed and high-efficiency vertical-horizontal conversion processing machine tool. The specific steps for designing the aforementioned processing machine tool are: Step 1. Overall structure design of machine tool; Step 2. Based on the overall structure of the aforementioned machine tool, the dimensions of the dual five-axis motion components are designed; Step 3. Select the motor and controller for each axis of the dual five-axis motion assembly; Step 4. Based on the motor and controller selection of each axis, perform mechanical structure modeling, electrical system modeling, and controller modeling for each axis; Step 5. Based on the three models in step 4, build the dynamic model of each axis feed servo system; Step 6. Confirm the model parameters of the feed servo system dynamics model of each axis by estimation or table lookup; Step 7. Perform model simulation to obtain a step response curve; Step 8. Calculate the overshoot and steady-state error according to the step response curve of each axis. If they exist, return to step 6 and change the controller parameters in the model. If they do not exist, go to step 9. Step 9. Calculate the adjustment time of each axis according to the step response curve of each axis. If the adjustment time is large or the difference between the adjustment times of each axis is large, return to step 2 and modify the size of each axis. If the adjustment time or the difference between the adjustment times meets the time threshold, proceed to step 10. Step 10: Carry out machine tool manufacturing.

[0011] Compared with the prior art, the present invention has at least the following beneficial effects: utilizing the directional feeding mechanism to provide the machine tool spindle with movement along the three linear coordinate axes of X, Y and Z, as well as movement along the two rotating coordinate axes of C and B installed at an angle of 45° thereto, the machine tool can satisfy the requirements of synchronous or asynchronous processing of workpieces by the spindles on both sides in a vertical or horizontal manner.

[0012] The machine tool adopts a vertical-horizontal conversion spindle, which can perform milling on the workpiece in a vertical or horizontal manner, realize the full process processing of the workpiece in one clamping, and avoid the problem of reduced processing accuracy caused by multiple clamping of the workpiece. The machine tool adopts a fully enclosed symmetrical structure, which has the structural characteristics of high rigidity and high stability. At the same time, through the CNC machining program, the spindles on both sides can realize symmetrical and synchronous milling of the workpiece, which can effectively improve the force characteristics of the machining process and improve the machining quality and machining efficiency of the workpiece. The present invention can not only be used for rough machining, but also is particularly suitable for fine machining, which can greatly improve the production and processing efficiency of parts, and the machining efficiency is increased by more than 50%, which can significantly improve the economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings are only for the purpose of illustrating particular embodiments and are not to be construed as limiting the invention.

[0014] Figure 1 It is a front view of the processing machine tool of the present invention; Figure 2 A top view of the processing machine tool of the present invention; Figure 3 A side view of a processing machine tool of the present invention; Figure 4 It is a design flow chart of the processing machine tool of the present invention; Figure 5 Schematic diagram of the step response curve of the feed servo system.

[0015] Reference numerals: 1. Bed frame, 2. Rotating table, 3. Workpiece to be processed, 4-1. Y-axis moving parts, 5-1. X-axis moving parts, 6-1. Z-axis moving parts, 7-1. C-axis rotating parts, 8-1. B-axis rotating parts, 9-1. Machine tool spindle, 10-1. Processing tool, 11. CNC device, 12-1. Y-axis guide rail, 13-1. X-axis guide rail, 14-1. Z-axis guide rail. DETAILED DESCRIPTION

[0016] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. In addition, the present invention can also be implemented in other ways different from those described herein, and therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0017] A specific embodiment of the present invention, as Figure 1-Figure 5 , discloses a dual-spindle dual-five-axis linkage high-speed and efficient vertical-horizontal conversion processing machine tool, comprising a bed frame 1, a rotary table 2, two sets of five-axis motion components and two machine tool spindles; The bed frame 1 includes a processing platform and a track mounting frame; the track mounting frame includes a first side surface and a second side surface; the processing platform is arranged between the first side surface and the second side surface, and the first side surface and the second side surface are both perpendicular to the processing platform; two groups of symmetrical left and right groups of 4 Y-axis guide rails 12-1 are installed on the first side surface and the second side surface through mounting holes, and the 4 Y-axis guide rails 12-1 are all perpendicular to the processing platform.

[0018] The rotary table 2 is arranged at the center of the processing platform. When in use, the workpiece 3 to be processed is mounted on the rotary table 2 through a fixture; Furthermore, the five-axis motion assembly includes a Y-axis motion component 4-1, an X-axis guide rail 13-1, an X-axis motion component 5-1, a Z-axis guide rail 14-1, a Z-axis motion component 6-1, a C-axis rotation component 7-1 and a B-axis rotation component 8-1; the five-axis motion assembly is arranged on two sets of Y-axis guide rails 12-1.

[0019] Both ends of the Y-axis moving component 4 - 1 are slidably disposed on the left and right sets of Y-axis guide rails 12 - 1 through sliders, and slide on the Y-axis guide rails 12 - 1 .

[0020] Preferably, see the attached Figure 1 , driven by two sets of left and right linear motors.

[0021] A mounting hole is provided inside the Y-axis moving component 4-1, and two groups of four X-axis guide rails 13-1 are installed symmetrically in the upper and lower directions through the mounting hole. The upper and lower side surfaces of the X-axis moving component 5-1 are slidably provided on the upper and lower groups of X-axis guide rails through sliders respectively; Preferably, see the attached Figure 1 , driven by two sets of upper and lower linear motors.

[0022] A mounting hole is provided inside the X-axis motion component 5-1, and two groups of four Z-axis guide rails 14-1 are installed through the mounting hole. The left and right sides of the Z-axis motion component 6-1 are slidably provided on the two groups of Z-axis guide rails 14-1 through sliders. Preferably, see the attached Figure 1 , driven by two sets of left and right linear motors.

[0023] A C-axis rotating component 7-1 is installed at the end of the Z-axis moving component 6-1 close to the rotating table 2. The C-axis rotating component 7-1 rotates around the axis of the Z-axis moving component 6-1 and realizes rotation around the Z-axis through a torque motor driving structure. The B-axis rotating component 8-1 is installed at the end of the C-axis rotating component 7-1 at an angle of 45°, so that the rotation center of the B-axis rotating component 8-1 forms an angle of 45° with the axis of the Z-axis moving component 6-1, and is driven by a torque motor to achieve rotation; A machine tool spindle 9-1 is installed at an angle of 45° at the end of the B-axis rotating component 8-1, so that the axis of the machine tool spindle 9-1 forms an angle of 45° with the rotation center of the B-axis rotating component 8-1; Furthermore, by rotating the C-axis rotating component 7-1 and the B-axis rotating component 8-1, the axis of the machine tool spindle 9-1 and the Z-axis moving component 6-1 can be switched to a parallel or vertical state; A machining tool 10 - 1 for machining the workpiece 3 is provided at the end of the machine tool spindle 9 - 1 .

[0024] Furthermore, it also includes a numerical control device 11, the bed frame 1 is electrically connected to the numerical control device 11, and the numerical control device 11 is used to input and control numerical control programs and respectively control two groups of five-axis motion components to realize the processing operations of the machine tool spindles arranged on both sides of the machine tool on the workpiece 3 to be processed.

[0025] Preferably, the numerical control device 11 adopts a dual-channel control method, performs 5-axis linkage control on the five-axis motion devices on both sides respectively, and uses the rotary table 2 for indexing control, thereby realizing the 6-axis 5-linkage on both sides of the workpiece 3 to be processed, and performing synchronous or asynchronous milling processing.

[0026] Preferably, the bed frame adopts a four-gantry closed integral frame structure with high rigidity and high stability. The five-axis motion components installed on both sides of the bed structure frame adopt the same structure.

[0027] Furthermore, due to the use of linear motors for direct drive, the intermediate mechanical transmission link is avoided, and the feed servo system of each axis has the advantages of fast feed speed and high precision. However, at the same time, the cutting load changes and external disturbances act directly on the linear motor without being attenuated by any intermediate transmission link. The dynamic performance of the feed servo system of each axis will directly affect the processing quality of the parts. Therefore, it is necessary to reasonably design the machine tool size during the machine tool design stage, and reasonably select the linear motor and controller to improve the dynamic performance of the feed servo system of each axis, and finally improve the processing efficiency of the machine tool and the processing quality of the parts.

[0028] Another aspect of the present invention is Figure 4 , and also provides a design method for the aforementioned linkage high-speed and high-efficiency vertical-horizontal conversion processing machine tool, the specific steps are: Step 1. Overall structure design of machine tool; Step 2. Based on the overall structure of the aforementioned machine tool, the dimensions of the dual five-axis motion components are designed; Step 3. Select the motor and controller for each axis of the dual five-axis motion assembly; Step 4. Based on the motor and controller selection of each axis, perform mechanical structure modeling, electrical system modeling, and controller modeling for each axis; Step 5. Based on the three models in step 4, build the dynamic model of each axis feed servo system; Step 6. Confirm the model parameters of the feed servo system dynamics model of each axis by estimation or table lookup; Step 7. Simulate the model on the Simulink tool in MATLAB to obtain the step response curve; Step 8. Calculate the overshoot and steady-state error according to the step response curve of each axis. If they exist, return to step 6 and change the controller parameters in the model. If they do not exist, go to step 9. Step 9. Calculate the adjustment time of each axis according to the step response curve of each axis. If the adjustment time is large or the difference between the adjustment times of each axis is large, return to step 2 and modify the size of each axis. If the adjustment time or the difference between the adjustment times meets the time threshold, proceed to step 10. Step 10: Carry out machine tool manufacturing.

[0029] Furthermore, in step 4, based on the selection of motors and controllers for each axis, a specific method of mechanical structure modeling, electrical system modeling and controller modeling for each axis is performed. Taking the Z-axis motion component 6-1 as an example, a simplified Z-axis feed servo system dynamic model modeling method is demonstrated, which mainly includes three parts: mechanical structure modeling including the Z-axis motion component 6-1, the C-axis rotating component 7-1, the B-axis rotating component 8-1, the machine tool spindle 9-1 and the machining tool 10-1; electrical system modeling including structures such as the linear motor mover and stator in the Z-axis motion component 6-1; controller modeling for controlling the motion of the linear motor in the Z-axis motion component 6-1.

[0030] Furthermore, in terms of mechanical structure modeling, a single-degree-of-freedom mass-damper system is used to perform equivalent abstraction of the interaction force between mechanical structures, and the thrust of the linear motor of the moving part on the mechanical structure is determined. The expression is:

[0031] in, represents the thrust of the linear motor of the Z-axis moving component 6-1 on the mechanical structure; It represents the equivalent damping coefficient of the mechanical structure moving along the axis 6-1 of the Z-axis moving part; Represents the total mass of the mechanical structure; Indicates the actual position of the mechanical structure along the axis of the Z-axis moving component 6-1; Indicates the current moment.

[0032] Furthermore, in terms of electrical system modeling, according to Kirchhoff's voltage law, the voltage balance equation in the armature is obtained as follows:

[0033] in, Indicates the voltage of the stator armature winding of the linear motor; Represents the armature winding resistance; Represents the armature winding current; represents the armature winding inductance; Represents the back electromotive force generated by the movement of the mover.

[0034] In addition, the back electromotive force generated by the motion of the mover It is related to the movement speed and the expression is:

[0035] in, Represents the back electromotive force coefficient of the motor.

[0036] In addition, the linear motor's thrust on the mechanical structure It is mainly related to the armature winding current, and the expression is:

[0037] in, Indicates the thrust coefficient of the motor.

[0038] Combining the above three equations, the stator armature winding voltage of the linear motor is obtained: The thrust of the linear motor on the mechanical structure The relationship is expressed as:

[0039] Furthermore, in terms of controller modeling, a speed feedforward control strategy is adopted, and the expression is:

[0040] in, Indicates the position difference along the axis direction of the Z-axis moving component 6-1; Indicates the command position issued by the numerical control device 11 to the Z-axis moving component 6-1; Indicates the command speed during the control process; Represents position proportional gain; Indicates the speed difference during control; Indicates the actual speed of the mechanical structure along the axis of the Z-axis moving component 6-1; Indicates position speed feedforward; Indicates the command current during the control process; represents the speed proportional gain; represents the velocity integration time constant; Indicates the current difference during the control process; Represents the actual current of the linear motor in the Z-axis motion component 6-1; represents the current proportional gain; Represents the current integration time constant.

[0041] Furthermore, the Y-axis motion component 4-1, the X-axis motion component 5-1, the C-axis rotation component 7-1, and the B-axis rotation component 8-1 can all adopt this method to build a feed servo system dynamics model.

[0042] Furthermore, the feed servo system is essentially a time domain system, and its stability and various performances can be analyzed in the time domain. Its position control loop should have the following performance: the response to the command should be as fast as possible without overshoot and the command position can be accurately reached in the end. Therefore, when analyzing its performance indicators, the overshoot can be used as the and steady-state error As a basic prerequisite, the adjustment time As an indicator to measure its response efficiency. Among them, the overshoot , which represents the ratio of the maximum deviation between the output value and the steady-state value to the steady-state value; steady-state error , which represents the difference between the steady-state value of the system and the input value when time tends to infinity; the adjustment time , indicating that the response curve reaches and remains within the allowable range of steady-state error The time is usually ,like Figure 5 Show.

[0043] Furthermore, based on the aforementioned dynamic model of the feed servo system of each axis, the Simulink tool in MATLAB can be used to simulate and obtain the step response curve of the position control loop of the feed servo system, and then calculate the overshoot, steady-state error and adjustment time. If there is an overshoot or steady-state error, the controller parameters may be set incorrectly. The controller parameters should be appropriately changed so that there is no overshoot and no steady-state error. If the adjustment time is large, or the adjustment time difference of each axis is large, it may be that the single-axis dynamic characteristics are poor or the multi-axis servo is not matched. Under the premise of maintaining the rigidity of the machine tool, the size of each axis of the machine tool should be appropriately modified, the mass of the moving parts should be reduced, or a linear motor that meets the requirements should be selected.

[0044] Based on the above operations, the dynamic performance of the feed servo system of each axis of the machine tool can be considered in the machine tool design stage, providing a reference for the machine tool size design and linear motor selection, ensuring that the dynamic performance of the machine tool in the actual processing process meets the expected requirements, and improving the processing efficiency of the machine tool and the processing quality of parts.

[0045] The present invention provides a dual-spindle dual-five-axis linkage high-speed and efficient vertical-horizontal conversion processing machine tool, such as Figure 1As shown, the synchronous or asynchronous milling of the workpiece to be processed by the dual spindles in a vertical or horizontal manner can be realized. The workpiece 3 to be processed is fixed on the rotary table 2 by a fixture, and the machine tool spindle realizes linear motion in the X, Y, and Z axes of the machine tool and rotational motion around the Z axis and the 45° B axis rotation center through the machine tool X, Y and Z axis axial motion devices and C and B axis rotating parts, and can process the workpiece 3 to be processed in a vertical or horizontal manner. The numerical control device 11 controls the numerical control processing program to realize the dual five-axis linkage motion of the machine tool, thereby realizing the synchronous or asynchronous milling of the workpiece 3 to be processed by the dual spindles of the machine tool in a vertical or horizontal manner.

[0046] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A linkage high-speed and high-efficiency vertical-horizontal conversion processing machine tool, characterized in that: It includes a bed frame, a rotary table, two sets of five-axis motion components and two sets of machining tools; The bed frame includes a processing platform and a track mounting frame; the track mounting frame includes a first side surface and a second side surface; the processing platform is arranged between the first side surface and the second side surface; the first side surface and the second side surface are both provided with a Y-axis guide rail; the rotary table is arranged at the center of the processing platform; One set of five-axis motion components is disposed on the Y-axis guide rail on the first side; another set of five-axis motion components is disposed on the Y-axis guide rail on the second side; The five-axis motion assembly includes a Y-axis motion component, an X-axis guide, an X-axis motion component, a Z-axis guide, a Z-axis motion component, a C-axis rotating component, a B-axis rotating component, a machine tool spindle, and a processing tool; A C-axis rotating component is installed at the end of a Z-axis moving component, a B-axis rotating component is installed at the end of the C-axis rotating component at a first angle, a machine tool spindle is arranged at the end of the B-axis rotating component at a second angle, and a machining tool is arranged at the end of the machine tool spindle.

2. The processing machine tool according to claim 1, characterized in that: The first angle and the second angle have the same degree.

3. The processing machine tool according to claim 2, characterized in that: The first angle and the second angle are 45°.

4. The processing machine tool according to claim 1, characterized in that: A mounting hole is arranged inside the Y-axis moving component, an X-axis guide rail is arranged based on the mounting hole, and the X-axis moving component is slidably arranged on the X-axis guide rail through a slider and slides on the X-axis guide rail.

5. The processing machine tool according to claim 1, characterized in that: A mounting hole is arranged inside the X-axis component, a Z-axis guide rail is arranged based on the mounting hole, and the Z-axis moving component is slidably arranged on the Z-axis guide rail through a slider, and slides on the Z-axis guide rail.

6. The processing machine tool according to claim 1, characterized in that: It also includes a numerical control device, the bed frame is electrically connected to the numerical control device, the numerical control device is used to input and control numerical control programs and respectively control two groups of five-axis motion components for switching the parallel or vertical state of the machine tool spindle.

7. A method for designing a linked high-speed and high-efficiency vertical-horizontal conversion processing machine tool, used for designing the processing machine tool of any one of claims 1 to 6, characterized in that: The specific steps are: Step 1. Overall structure design of machine tool; Step 2. Based on the overall structure of the aforementioned machine tool, the dimensions of the dual five-axis motion components are designed; Step 3. Select the motor and controller for each axis of the dual five-axis motion assembly; Step 4. Based on the motor and controller selection of each axis, perform mechanical structure modeling, electrical system modeling, and controller modeling for each axis; Step 5. Based on the three models in step 4, build the dynamic model of each axis feed servo system; Step 6. Confirm the model parameters for the dynamics model of the feed servo system of each axis mentioned above; Step 7. Perform model simulation to obtain a step response curve; Step 8. Calculate the overshoot and steady-state error according to the step response curve of each axis. If they exist, return to step 6 and change the controller parameters in the model. If they do not exist, go to step 9. Step 9. Calculate the adjustment time of each axis according to the step response curve of each axis. If the adjustment time is large or the difference between the adjustment times of each axis is large, return to step 2 and modify the size of each axis. If the adjustment time or the difference between the adjustment times meets the time threshold, proceed to step 10. Step 10: Carry out machine tool manufacturing.

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