Linear motor combined motion module and control process thereof

Abstract

The invention relates to a linear motor combined motion module and a control process thereof, the linear motor combined motion module comprises a linear module and an arc-shaped module which is rapidly assembled and replaced with the linear module through a standardized interface, the bottom end of a stator is fixedly connected with a track base, and a permanent magnet array is installed at the top end of the stator. The top end of the track base is slidably connected with a moving plate through a guide rail, an inserting piece is arranged on the side wall of the moving plate, a U-shaped groove sensor is arranged on the side wall of the track base, the inserting piece is slidably connected with the U-shaped groove sensor in an inserted mode, and the linear module and the arc-shaped module are combined to form a U-shaped track or an annular track. And the linear, U-shaped and ring-shaped structure can be kept stable under high-speed operation, and is low in noise and high in precision. The linear motor combined motion module has the advantages of track diversity, high speed, high precision, stability, no noise, modular assembly, improvement of cooling efficiency and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of combined motion modules, and particularly relates to a linear motor combined motion module and a control process thereof. BACKGROUND

[0002] At present, commonly used motion modules of industrial equipment mainly include the following two types: 1. Screw nut and linear guide rail structure: the screw nut mechanism is stable and reliable, and has high precision, and is suitable for medium and low speed linear motion; the disadvantage is that it can only make linear motion, and the speed is limited, and it is not suitable for high speed and complex path operation scenarios.

[0003] 2. Rack and pinion structure: the rack and pinion can realize linear and curved motion, and is suitable for various track shapes; the disadvantage is that due to the meshing characteristics of the gear, the operation is not smooth, the noise is large, and the execution precision is affected by the tooth shape error and gap.

[0004] In high-end equipment manufacturing, electronic assembly, automatic detection and other industries, users hope to have linear and curved running capability in the same set of motion system, and also consider high speed, low noise and high precision, and the existing technology is difficult to meet these requirements at the same time.

[0005] Therefore, we have developed a linear motor combined motion module to solve the above problems. SUMMARY

[0006] The present application aims to overcome the shortcomings of the prior art and provide a linear motor combined motion module, which has the advantages of trajectory diversity, high speed and high precision, smoothness and noiselessness, modular assembly, improved cooling efficiency and the like.

[0007] To achieve the above purpose, the technical scheme adopted by the present application is as follows: a linear motor combined motion module, the linear motor combined motion module comprising a linear module and an arc-shaped module which is quickly assembled and replaced with the linear module through a standardized interface, the linear module and the arc-shaped module being combined to form a U-shaped track or a ring-shaped track; a stator, the bottom end of the stator being fixedly connected with a track base, a permanent magnet array being installed at the top end of the stator, the top end of the track base being slidingly connected with a moving plate through a guide rail, an insertion piece being arranged at the side wall of the moving plate, a U-shaped groove sensor being arranged at the side wall of the track base, and the insertion piece being slidingly inserted with the U-shaped groove sensor; a mover, the mover being slidingly connected at the top end of the stator, and being provided with a coil winding and being arranged to interact with the permanent magnet at the top end of the stator to generate a linear driving force; permanent magnets, which are arranged in a segmented staggered manner at the middle position of the top end of the stator, so as to optimize the magnetic flux distribution; a linear encoder, which is arranged on the outer wall of the track base and is used for real-time position feedback through a controller; The controller, equipped with a power drive unit, is located on the outer wall of the track base and above the linear encoder, and performs closed-loop control of the position, speed, and acceleration of the moving plate. The cooling system is located at the two bottom corners of the track base to control the temperature rise of the motion module during operation.

[0008] Preferably, the permanent magnets are divided into multiple groups and arranged in a equidistant manner, with adjacent groups staggered by a non-integer pole pitch along the direction of motion.

[0009] Preferably, the pole pitch of the motion module is matched with the slot pitch of the coil winding in a non-integer ratio, which reduces thrust fluctuation by 66% at 3m / s.

[0010] Preferably, the permanent magnet arrangement structure has a lower operating noise of 55dB than the conventional equidistant arrangement under the same driving current, with the permanent magnet noise being 44dB.

[0011] Preferably, each permanent magnet has a magnetic permeable sheet on its back side. The magnetic permeable sheet is made of low-loss silicon steel or soft magnetic composite material and forms a magnetic flux concentration channel.

[0012] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: 1. Trajectory diversity: The linear motor combined motion module can realize straight lines, curves, U-shapes, circles and other trajectories.

[0013] 2. High speed and high precision: The maximum speed can reach 5m / s, and the repeatability is better than ±2μm.

[0014] 3. Smooth and noiseless operation: The arrangement of permanent magnets eliminates the cogging effect, achieving operation without mechanical meshing noise.

[0015] 4. Modular assembly: Straight and curved modules can be quickly assembled and replaced, shortening the equipment adjustment cycle.

[0016] 5. High cooling efficiency: The cooling system at the bottom corner of the track base supports long-term high-speed operation, with the temperature rise controlled within 40℃.

[0017] 6. Low maintenance cost: There are no mechanical meshing parts, resulting in less wear and longer maintenance cycles. Attached Figure Description

[0018] Figure 1 This is a perspective view of the linear motor combined motion module described in this invention.

[0019] Figure 2 For the present invention Figure 1 Enlarged view of point C in the middle.

[0020] Figure 3 This is a perspective view of the arc-shaped module described in this invention.

[0021] Figure 4 For the present invention Figure 3 Sectional view at point B.

[0022] Figure 5 This is the front view of the linear module described in this invention.

[0023] Figure 6 For the present invention Figure 5 Sectional view at point A in the middle.

[0024] Figure 7 For the present invention Figure 5 A bottom view.

[0025] Figure 8 This is a schematic diagram of the permanent magnet arrangement of the present invention.

[0026] Figure 9 This is a control flowchart of the linear motor combined motion module described in this invention. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0028] Figures 1 to 7 In the present invention, a linear motor combined motion module includes a linear module 1 and an arc module 2 that can be quickly assembled and replaced with the linear module 1 through a standardized interface. The linear module 1 and the arc module 2 are combined to form a U-shaped trajectory or a circular trajectory. The stator 3 has a track base 100 fixedly connected to its bottom end, and a permanent magnet array 5 is installed on its top end. A movable plate 101 is slidably connected to the top end of the track base 100 via a guide rail 10. An insert 41 is provided on the side wall of the movable plate 101, and a U-shaped groove sensor 91 is provided on the side wall of the track base 100. The insert 41 and the U-shaped groove sensor 91 are slidably inserted into each other. The mover 4 is slidably connected to the top end of the stator 3, and has a coil winding 6 installed thereon. The mover interacts with the permanent magnets 5 at the top end of the stator 3 to generate a linear driving force.

[0029] The permanent magnet 5 is arranged in a segmented, staggered phase configuration at the top center of the stator 3 to optimize magnetic flux distribution. Figure 8 As shown, the permanent magnets 5 are arranged in multiple groups, with each group maintaining an equidistant arrangement and adjacent groups offset by a non-integer pole pitch along the direction of motion. Under the same driving current, this arrangement of permanent magnets 5 results in a noise level 54 dB lower than the conventional equidistant arrangement (55 dB). Each permanent magnet 5 has a magnetic permeable sheet on its back, made of low-loss silicon steel or soft magnetic composite material, forming a concentrated magnetic flux channel. The pole pitch of the motion module is matched to the slot pitch of the coil winding 6 using a non-integer ratio, reducing thrust fluctuation by 66% at 3 m / s.

[0030] Linear encoder 7 is installed on the outer wall of track base 100 and provides real-time position feedback through controller 8. Controller 8 is equipped with a power drive unit, installed on the outer wall of track base 100 and located above linear encoder 7, and performs closed-loop control of the position, speed, and acceleration of moving plate 101.

[0031] Cooling system 9, located at the two bottom corners of track base 100, controls the temperature rise of the motion module during operation, ensuring that the temperature rise of the combined motion module does not exceed 40°C after 8 hours of continuous operation.

[0032] Multiple linear modules combined with arc modules can form a circular trajectory. Performance tests showed that at a running speed of 5 m / s, the repeatability was ±2μm, the trajectory switching was smooth and shock-free, the operating noise was less than 45dB, and the temperature rise did not exceed 40℃ after 8 hours of continuous operation.

[0033] 1. Segmented staggered arrangement The permanent magnets are divided into several groups, such as 4 or 6 groups, with each group maintaining an equidistant arrangement. However, adjacent groups are staggered along the direction of motion by a non-integer pole pitch, for example, 0.25 to 0.35 times the pole pitch. This staggered arrangement allows the cogging forces generated by the permanent magnets in each group to cancel each other out in phase, thereby significantly reducing the cogging effect. Figure 8 As shown.

[0034] 2. Polar distance optimization Conventional pole pitch is usually equal to the center distance between magnetic poles. In this invention, the pole pitch and winding slot pitch are matched in a non-integer ratio, such as a pole pitch to slot pitch ratio of 0.96 or 1.04, to avoid the cogging force from being simultaneously superimposed across the entire stator length. Optimizing the pole pitch through finite element simulation can reduce thrust fluctuation by more than 30%, with a measured reduction of 66%, as shown in Table 1.

[0035] 3. Centralized flux design A magnetic permeable sheet is added to the back of each permanent magnet, using low-loss silicon steel or soft magnetic composite material, to form a concentrated magnetic flux channel. This concentrated magnetic flux design not only improves the effective air gap magnetic density by approximately 8% to 12%, but also reduces magnetic leakage and improves energy efficiency.

[0036] Through finite element simulation and prototype testing of this invention, the permanent magnet arrangement structure, under the same driving current, exhibits the following performance improvements compared to the conventional equidistant arrangement, as shown in Table 1: Table 1 Comparison of performance indicators between conventional equidistant permanent magnet arrangements and the present invention. Performance indicators Conventional equidistant arrangement Arrangement of the invention Lift amplitude Tooth slot force peak 100% 35% ↓65% Thrust fluctuation (high speed 3 m / s) ±6.2% ±2.1% ↓66% Effective thrust density Reference value +15% ↑15% Operating noise (dB) 55 dB 44 dB ↓20% Continuous operating temperature rise 55℃ 40℃ ↓27% Figure 9 The control process of a linear motor combined motion module includes the following steps: S10. The command signal generator issues motion commands / target trajectories.

[0037] S20. The controller receives the command signal, performs trajectory planning / velocity feedforward, and performs acceleration / deceleration planning for the CNC system curve to obtain the predicted value r. p (t).

[0038] S30. The controller uses PID / PI regulation with proportional, integral, and derivative control, as well as speed feedforward / model prediction, and controls the current of the linear motor coil winding according to the command signal to drive the linear motor to rotate; the thrust density of the linear motor is increased by more than 15%.

[0039] S40. The power drive unit of the controller sends the feedback signal to the controller through PWM power amplification.

[0040] S50. The linear motors at the top of the linear module and the arc module drive the moving plate 101 to produce displacement.

[0041] S60. The linear encoder monitors the position of the linear motor in real time. The linear encoder is equipped with a sensor that monitors the speed of the linear motor in real time. The repeatability of the linear motor is within ±2μm. The maximum speed of the linear motor is 5m / s.

[0042] S70. After the linear encoder feedback, the error e(t) is calculated; the error is equal to the difference between the predicted value and the measured value, e(t) = r p (t)-y(t).

[0043] S80. After error calculation, the data is returned to the controller for processing.

[0044] The command signal generator issues the desired motion command. The servo driver receives, processes, and amplifies the command signal, controlling the motor winding current according to the command signal to drive the motor to rotate. The position / speed feedback device monitors the motor's position and speed in real time and sends feedback signals to the servo driver. The control algorithm calculates the appropriate control quantity based on the error signal, adjusting the motor winding current to eliminate the error. The motor continuously adjusts until it reaches the desired position or speed.

[0045] This invention includes a linear module and an arc module. The stator 3 of the linear module is mounted on a linear track base, and the stator 3 of the arc module is mounted on an arc track base machined according to the designed curvature. The mover 4 is arranged parallel to the stator 3 and has coil windings 6 installed inside. The permanent magnet 5 is fixed to the surface of the stator and adopts a segmented staggered phase arrangement to improve thrust and reduce cogging effect. A section of linear module and a section of 180° arc module can be quickly assembled through a standardized interface to form a U-shaped track; multiple linear modules and arc modules can be combined to form a circular track. A linear encoder 7 is mounted on the side of the track base and provides real-time position feedback to the controller 8. The controller performs closed-loop control based on the feedback signal and the target track. A cooling system 9 is arranged inside the stator or at the bottom of the track base to ensure stable coil temperature. At a running speed of 5 m / s, the repeatability is ±2μm, the track switching is smooth and shock-free, the operating noise is below 45dB, and the temperature rise does not exceed 40℃ after 8 hours of continuous operation.

[0046] The above are merely specific application examples of the present invention and do not constitute any limitation on the scope of protection of the present invention. All technical solutions formed by equivalent transformations or substitutions fall within the scope of protection of the present invention.

Claims

1. A linear motor combined motion module, characterized in that, The linear motor combined motion module includes a linear module (1) and an arc module (2) that can be quickly assembled and replaced with the linear module (1) through a standardized interface. The linear module (1) and the arc module (2) are combined to form a U-shaped trajectory or a circular trajectory. The stator (3) has a track base (100) fixedly connected to its bottom end. A permanent magnet (5) array is installed on the top of the stator (3). The top of the track base (100) is slidably connected to the moving plate (101) via the guide rail (10). The moving plate (101) has a insert (41) on its side wall. The track base (100) has a U-shaped groove sensor (91) on its side wall. The insert (41) and the U-shaped groove sensor (91) are slidably inserted into each other. The mover (4) is slidably connected to the top of the stator (3), and is equipped with a coil winding (6), which interacts with the permanent magnet (5) at the top of the stator (3) to generate a linear driving force; The permanent magnet (5) is arranged in a segmented staggered phase at the middle position of the top of the stator (3) to optimize the magnetic flux distribution; A linear encoder (7) is installed on the outer wall of the track base (100) and provides real-time position feedback through a controller (8); The controller (8) is equipped with a power drive unit, which is located on the outer wall of the track base (100) and above the linear encoder (7) to perform closed-loop control of the position, speed and acceleration of the moving plate (101); The cooling system (9) is located at the two bottom corners of the track base (100) to control the temperature rise of the motion module during operation.

2. The linear motor combined motion module according to claim 1, characterized in that, The permanent magnets (5) are divided into multiple groups and arranged in a equidistant manner. The adjacent groups are staggered by a non-integer pole pitch along the direction of motion.

3. The linear motor combined motion module according to claim 2, characterized in that, The pole pitch of the motion module is matched with the slot pitch of the coil winding (6) in a non-integer ratio, and the thrust fluctuation is reduced by 66% at 3m / s.

4. The linear motor combined motion module according to claim 1, characterized in that, Under the same driving current, the noise of the permanent magnet (5) arrangement structure is 55dB lower than that of the conventional equidistant arrangement, and the noise of the permanent magnet (5) is 44dB.

5. The linear motor combined motion module according to claim 1, characterized in that, Each permanent magnet (5) has a magnetic permeable sheet on its back. The magnetic permeable sheet is made of low-loss silicon steel or soft magnetic composite material and forms a magnetic flux concentration channel.

6. The control flow of a linear motor combined motion module according to claim 1, characterized in that, Includes the following steps: S10. The command signal generator issues motion commands / target trajectories; S20. The controller receives the command signal, performs trajectory planning / velocity feedforward, and obtains the predicted value r. p (t); S30. The controller uses PID control with proportional, integral, and derivative functions to adjust the current in the linear motor coil windings according to the command signal, thereby driving the linear motor to rotate. S40. The controller's power drive unit sends the feedback signal to the controller through PWM power amplification; S50. The linear motors at the top of the linear module and the arc module drive the moving plate (101) to generate displacement; S60. The linear encoder monitors the position of the linear motor in real time. The linear encoder is equipped with a sensor that monitors the speed of the linear motor in real time. S70. After the linear encoder feedback, the error e(t) is calculated; S80. After error calculation, the data is returned to the controller for processing.

7. The control flow of the linear motor combined motion module according to claim 6, characterized in that, In step S30, the thrust density of the linear motor is increased by more than or equal to 15%.

8. The control flow of the linear motor combined motion module according to claim 6, characterized in that, In step S60, the repeatability of the linear motor is within ±2μm.

9. The control flow of the linear motor combined motion module according to claim 6, characterized in that, In step S60, the maximum speed of the linear motor is 5 m / s.

10. The control flow of the linear motor combined motion module according to claim 6, characterized in that, In step S70, the error is equal to the difference between the predicted value and the measured value, e(t) = r p (t)-y(t).

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