Transmission system and its control method

Abstract

The present invention relates to the technical field of transmission systems, and more particularly, to a transmission system and a control method thereof. The transmission system includes a stator, a mover, a position detection module, and a control module; the mover has a magnet array, the stator includes a first stator and a second stator arranged in sequence along the transmission direction with a gap therebetween, and the mover can move under the interaction of the stator coils of the stator and the magnet array; the control module is configured to: when the mover crosses the gap, control the first current flowing through the stator coil of the first stator and / or the second current flowing through the stator coil of the second stator according to the real-time position of the mover detected by the position detection module, so that the speed deviation of the mover at any position when crossing the gap is less than a set error. The transmission system and the control method provided by the present invention can greatly alleviate the speed fluctuation problem of the mover when crossing the gap, enabling the mover to cross the gap smoothly and smoothly.

Description

Technical Field

[0001] The present invention relates to the technical field of transmission systems, and more particularly, to a transmission system and a control method thereof. Background Art

[0002] A transmission system (conveyor line) generally includes a stator and a mover. Among them, there are multiple stators arranged in sequence along the transmission path. The stator has a stator coil, and the mover has a dynamic magnet. When the stator coil is energized, it can drive the dynamic magnet to move, driving the mover to move along the transmission path.

[0003] In the existing transmission system, there is generally a gap between adjacent stators. The existence of this gap is mainly due to the cost limitation of the stator module, and it is also for the convenience of equipment maintenance and adjustment. However, this gap design also brings significant technical problems: when the mover moves from one stator module to another stator module, it needs to cross this gap. During this process, the driving force of the mover will change, resulting in fluctuations in its running speed, and there may even be momentary pauses or acceleration phenomena. Such speed fluctuations will not only affect the smoothness of the transmission system but also may lead to a decrease in the accuracy of material transportation. Especially in a high-precision and high-efficiency industrial production environment, this problem is particularly prominent. Summary of the Invention

[0004] The purpose of the present invention is to provide a transmission system and a control method thereof to alleviate the technical problem of poor smoothness of the mover when crossing the gap in the existing transmission system.

[0005] The transmission system provided by the present invention includes a stator, a mover, a position detection module, and a control module.

[0006] The mover has a magnet array, and the magnet array includes a plurality of magnets arranged in sequence along the transmission path.

[0007] The stator includes a first stator and a second stator. The first stator and the second stator are arranged in sequence along the transmission direction and there is a gap between them. Both the first stator and the second stator have stator coils, and the mover can move relative to the stator along the transmission path under the interaction of the stator coil and the magnet array.

[0008] The control module is used for:

[0009] When the mover crosses the gap, according to the real-time position of the mover detected by the position detection module, control the first current and / or the second current so that the speed deviation at any position when the mover crosses the gap is less than a set error.

[0010] Wherein, the first current is the current flowing through the stator coil of the first stator, the second current is the current flowing through the stator coil of the second stator, and the speed deviation is the difference between the actual speed of the mover and the preset speed at the corresponding position.

[0011] Preferably, as an implementable manner, the position detection module is configured to:

[0012] Send a first position signal when it detects that the mover is between the first preset position and the second preset position;

[0013] Send a second position signal when it detects that the mover is between the second preset position and the third preset position; and

[0014] Send a third position signal when it detects that the mover is between the third preset position and the fourth preset position;

[0015] The control module is configured to:

[0016] Control the first current according to the first position signal;

[0017] Control the first current and / or the second current according to the second position signal; and

[0018] Control the second current according to the third position signal.

[0019] Wherein, the gap has a first gap edge and a second gap edge arranged in sequence along the transmission direction. The first preset position is the position where the mover is when its head end is flush with the first gap edge, the second preset position is the position where the mover is when its head end is flush with the second gap edge, the third preset position is the position where the mover is when its tail end is flush with the first gap edge, and the fourth preset position is the position where the mover is when its tail end is flush with the second gap edge.

[0020] Preferably, as an implementable manner, the first stator is provided with a first workstation, the second stator is provided with a second workstation, and the control module is configured to:

[0021] When the mover moves from the first workstation to the second workstation along the transmission path, control the first current and / or the second current according to the real-time position of the mover detected by the position detection module, so that the speed deviation of the mover at any position between the first workstation and the second workstation is less than the set error.

[0022] Preferably, as an implementable manner, the control module is configured to:

[0023] When the mover is moved from the first workstation to the first preset position, control the first current so that the mover accelerates uniformly to the first set speed and then moves at a constant speed; and

[0024] When the mover is moved from the fourth preset position to the second workstation, control the second current so that the mover accelerates uniformly to the second set speed and then decelerates uniformly to zero.

[0025] Preferably, as an implementable manner, the control module is configured to:

[0026] Control the first current to gradually increase according to the first position signal;

[0027] Control the first current to remain unchanged according to the second position signal, and control the second current to be equal to the first current; or, control the first current to gradually decrease and control the second current to gradually increase according to the second position signal; and

[0028] Control the second current to gradually decrease according to the third position signal.

[0029] Preferably, as an implementable manner, the control module controls the first current to decrease at a speed greater than the speed at which the second current increases according to the second position signal.

[0030] Preferably, as an implementable manner, the control module is configured to:

[0031] Control the first current and / or the second current to move the mover at a constant speed between the first preset position and the fourth preset position; or,

[0032] Control the first current and the second current to move the mover with uniform acceleration between the first preset position and the second preset position, move at a constant speed between the second preset position and the third preset position, and move with uniform deceleration between the third preset position and the fourth preset position; or,

[0033] Control the first current and / or the second current to move the mover with uniform acceleration between the first preset position and the fourth preset position.

[0034] Preferably, as an implementable manner, the control module is configured to:

[0035] Control the front coil in the transmission system to be energized in advance; and

[0036] Control the rear coil in the transmission system to be de-energized with a delay;

[0037] Among them, the front coil is located at the position where the mover is about to arrive, and the rear coil is located at the position where the mover has just passed.

[0038] Preferably, as an implementable manner, the length of the gap is less than the length of the magnet array on the mover;

[0039] And / or, the length of the gap is a multiple of the pole width on the mover;

[0040] And / or, the mover is covered with the magnets.

[0041] The present invention also provides a control method for a transmission system, and the method includes:

[0042] When the mover crosses the gap, according to the real-time position of the mover, control the first current and / or the second current, so that the speed deviation of the mover at any position is less than the set error.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] When the transmission system provided by the present invention is working, current is passed into the stator coil, which can enable the mover to move relative to the stator along the transmission path under the interaction of the stator coil and the magnet array. When the mover moves to the gap between the first stator and the second stator, it needs to cross this gap. During the process that the mover crosses the gap between the first stator and the second stator, the control module can control the first current and / or the second current according to the real-time position detected by the position detection module, so as to adjust the acting forces of the stator coil of the first stator and the stator coil of the second stator on the magnet array of the mover, so that the mover can maintain the force balance when crossing the gap. Thus, the actual speed of the mover at any position can be very close to the preset speed at the corresponding position, that is, the speed change of the mover conforms to the preset position and speed relationship. Thus, the speed deviation of the mover at any position when crossing the gap can be less than the set error, which can greatly alleviate the speed fluctuation problem of the mover when crossing the gap, and enable the mover to cross the gap smoothly and smoothly.

[0045] The control method of the transmission system provided by the present invention can, through the control of at least one of the first current and the second current, make the speed deviation of the mover at any position when crossing the gap less than the set error. Thus, the speed fluctuation problem of the mover when crossing the gap can be greatly alleviated, and the mover can cross the gap smoothly and smoothly. Description of the Drawings

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0047] Figure 1 Structural schematic diagram of the transmission system provided by the embodiment of the present invention;

[0048] Figure 2 Structural schematic diagram of the transmission system provided by the embodiment of the present invention;

[0049] Figure 3 First position and speed relationship diagram of the mover in the transmission system provided by the embodiment of the present invention;

[0050] Figure 4 Second position and speed relationship diagram of the mover in the transmission system provided by the embodiment of the present invention;

[0051] Figure 5 Third position and speed relationship diagram of the mover in the transmission system provided by the embodiment of the present invention.

[0052] Explanation of reference numerals:

[0053] 100 - stator coil;

[0054] 200 - mover; 210 - magnet;

[0055] 300 - position detection module;

[0056] 400 - transmission path. Detailed implementation manners

[0057] The following will clearly and completely describe the technical solutions of the present invention with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0058] The following will further describe the present invention in detail through specific implementation examples in combination with the drawings.

[0059] See Figure 1 and Figure 2, this embodiment provides a transmission system, which includes a stator, a mover 200, a position detection module 300, and a control module; the mover 200 has a magnet array, and the magnet array includes a plurality of magnets 210 arranged in sequence along a transmission path 400; the stator includes a first stator and a second stator, the first stator and the second stator are arranged in sequence along the transmission direction and there is a gap between them, both the first stator and the second stator have stator coils 100, and the mover 200 can move relative to the stator along the transmission path 400 under the interaction of the stator coils 100 and the magnet array.

[0060] The control module is configured to: when the mover 200 crosses the gap, control the first current and / or the second current according to the real-time position of the mover 200 detected by the position detection module 300, so that the speed deviation of the mover 200 at any position when crossing the gap is less than a set error. Wherein, the first current is the current applied to the stator coil 100 of the first stator, the second current is the current applied to the stator coil 100 of the second stator, and the speed deviation is the difference between the actual speed of the mover 200 and the preset speed at the corresponding position.

[0061] When the transmission system provided in this embodiment is working, a current is applied to the stator coil 100, which can make the mover 200 move relative to the stator along the transmission path 400 under the interaction of the stator coil 100 and the magnet array. When the mover 200 moves to the gap between the first stator and the second stator, it needs to cross this gap. During the process of the mover 200 crossing the gap between the first stator and the second stator, the control module can control the first current and / or the second current according to the real-time position detected by the position detection module 300, so as to adjust the acting forces of the stator coil 100 of the first stator and the stator coil 100 of the second stator on the magnet array of the mover 200, so that the mover 200 can maintain the force balance when crossing the gap. Thus, the actual speed of the mover 200 at any position can be very close to the preset speed at the corresponding position, that is, the speed change of the mover 200 conforms to the preset position-speed relationship. Therefore, the speed deviation of the mover 200 at any position when crossing the gap can be less than the set error, which can greatly alleviate the speed fluctuation problem of the mover 200 when crossing the gap, and make the mover 200 smoothly cross the gap.

[0062] Define the two end edges of the gap between the first stator and the second stator as the first gap edge and the second gap edge respectively, and the first gap edge and the second gap edge are arranged in sequence along the transmission direction. When the mover 200 crosses the gap, it will successively pass through the first preset position, the second preset position, the third preset position, and the fourth preset position. Among them, when the mover 200 reaches the first preset position, its head end is flush with the first gap edge; when the mover 200 reaches the second preset position, its head end is flush with the second gap edge; when the mover 200 reaches the third preset position, its tail end is flush with the first gap edge; when the mover 200 reaches the fourth preset position, its tail end is flush with the second gap edge. During the process of the mover 200 crossing the gap, the control module can control the first current and the second current in stages according to the position information of the mover 200 detected by the position detection module 300, specifically as follows:

[0063] In the first stage, when the position detection module 300 detects that the mover 200 is between the first preset position and the second preset position, it sends a first position signal. Since the magnet array of the mover 200 mainly interacts with the stator coil 100 of the first stator when the mover 200 moves between the first preset position and the second preset position, the control module can control the first current according to the first position signal to maintain the smoothness of the force exerted by the stator coil 100 of the first stator on the magnet array of the mover 200, so that the speed deviation of the mover 200 at any position between the first preset position and the second preset position is less than the set error.

[0064] In the second stage, when the position detection module 300 detects that the mover 200 is between the second preset position and the third preset position, it sends a second position signal. Since the magnet array of the mover 200 may interact with both the stator coil 100 of the first stator and the stator coil 100 of the second stator when the mover 200 moves between the second preset position and the third preset position, the control module can control one or both of the first current and the second current according to the second position signal, so that the speed deviation of the mover 200 at any position between the second preset position and the third preset position is less than the set error.

[0065] In the third stage, when the position detection module 300 detects that the mover 200 is between the third preset position and the fourth preset position, it sends a third position signal. Since the magnet array of the mover 200 mainly interacts with the stator coil 100 of the second stator when the mover 200 moves between the third preset position and the fourth preset position, the control module can control the second current according to the third position signal, so that the speed deviation of the mover 200 at any position between the third preset position and the fourth preset position is less than the set error.

[0066] When the mover 200 moves along the transmission path 400, it needs to stop at the workstations. Preferably, a first workstation is arranged on the first stator and a second workstation is arranged on the second stator, which can avoid the stagnation of the mover 200 when crossing the gap. Thus, the mover 200 can smoothly cross the gap without staying. When the mover 200 moves from the first workstation along the transmission path 400 to the second workstation, the control module can control either or both of the first current and the second current according to the real-time position of the mover 200 detected by the position detection module 300, so that the speed deviation of the mover 200 at any position between the first workstation and the second workstation is less than the set error. Thus, the mover 200 can move quickly and smoothly between the two workstations.

[0067] Further, when the mover 200 moves from the first workstation to the first preset position, the control module can control the first current so that the mover 200 accelerates uniformly to the first set speed and then moves at a constant speed to the first preset position; when the mover 200 moves from the fourth preset position to the second workstation, the control module can control the second current so that the mover 200 accelerates uniformly to the second set speed and then decelerates uniformly to zero and finally stops at the second workstation.

[0068] In the above first stage, the control module can control the first current to gradually increase according to the first position signal sent by the position detection module 300 to maintain the smoothness of the force of the stator coil 100 of the first stator on the magnet array of the mover 200.

[0069] In the above second stage, the following two methods can be used to control the first current and the second current: The first method, the control module can control the first current to remain unchanged according to the second position signal and control the second current to be equal to the first current to maintain the smoothness of the overall magnetic driving force of the stator coil 100 of the first stator and the stator coil 100 of the second stator on the mover 200; The second method, the control module can control the first current to gradually decrease according to the second position signal and control the second current to gradually increase after being equal to the first current to maintain the smoothness of the overall magnetic driving force of the stator coil 100 of the first stator and the stator coil 100 of the second stator on the mover 200.

[0070] In the above third stage, the control module can control the second current to gradually decrease according to the third position signal to maintain the smoothness of the force of the stator coil 100 of the second stator on the magnet array of the mover 200.

[0071] When the first current and the second current are controlled in the second way in the above-mentioned second stage, the speed of controlling the decrease of the first current is set to be greater than the speed of controlling the increase of the second current. It should be noted that the magnetic field energy density generated by the stator coil is proportional to the square of the applied current. When the starting currents of the first current and the second current are the same, only by making the speed of decreasing the first current greater than the speed of controlling the increase of the second current can the smoothness of the overall magnetic driving force be maintained. Specifically, the speed of decreasing the square value of the first current can be set to be equal to the speed of increasing the square value of the second current.

[0072] In addition, when the mover 200 crosses the gap, the control module can control the first current and the second current in any one of the following three ways:

[0073] First, as Figure 3 shown, the control module controls at least one of the first current and the second current so that the mover 200 moves at a constant speed between the first preset position and the fourth preset position, that is, the mover 200 moves at a constant speed throughout the process of crossing the gap.

[0074] Second, as Figure 4 shown, the control module controls the first current and the second current so that the mover 200 moves with uniform acceleration between the first preset position and the second preset position, moves at a constant speed between the second preset position and the third preset position, and moves with uniform deceleration between the third preset position and the fourth preset position.

[0075] Third, as Figure 5 shown, the control module controls at least one of the first current and the second current so that the mover 200 moves with uniform acceleration between the first preset position and the fourth preset position.

[0076] The stator coil 100 corresponding to the position where the mover 200 in the transmission system is about to arrive is defined as the front coil, and the stator coil 100 corresponding to the position where the mover 200 in the transmission system has just passed is defined as the rear coil. Preferably, the control module is made to control the front coil in the transmission system to be energized in advance and control the rear coil in the transmission system to be de-energized with a delay, so as to avoid the problem of unstable driving force of the mover 200 caused by untimely power-on or too fast power-off.

[0077] Preferably, the length of the gap between the first stator and the second stator is set to be less than the length of the dynamic magnet array on the mover 200 to ensure that the magnet array can always be driven by the stator coil 100 when the mover 200 crosses the gap.

[0078] Further, the length of the gap between the first stator and the second stator is set to be a multiple of the pole width on the mover 200, so that when the mover 200 crosses the gap, the part of the magnet array that is driven remains unchanged, facilitating control.

[0079] Preferably, the mover 200 can be fully covered with magnets 210. In this way, the integration degree can be improved, the volume can be reduced, and the upper limit of the driving force can be increased.

[0080] In addition, the relationship between the driving force of the stator coil 100 of the first stator on the mover 200 and the first current is set to be a linear relationship, and the relationship between the driving force of the stator coil 100 of the second stator on the mover 200 and the second current is set to be a linear relationship. Thus, the magnitude of the driving force can be adjusted by linearly controlling the magnitude of the current in the stator coil 100.

[0081] This embodiment also provides a control method for the above transmission system. The method includes: when the mover 200 crosses the gap, controlling the first current and / or the second current according to the real-time position of the mover 200, so that the speed deviation of the mover 200 at any position is less than the set error.

[0082] The control method provided by this embodiment can, by controlling at least one of the first current and the second current, make the speed deviation of the mover 200 at any position less than the set error when the mover 200 crosses the gap. Thus, the problem of speed fluctuation of the mover 200 when crossing the gap can be greatly alleviated, enabling the mover 200 to cross the gap smoothly.

[0083] This embodiment also provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium. When the computer program is executed by a processor, it implements each process of the control method embodiment of the above transmission system and can achieve the same technical effects. To avoid repetition, it will not be elaborated here. Among them, the computer-readable storage medium can be a read-only memory (ROM for short), a random access memory (RAM for short), a magnetic disk, or an optical disc, etc.

[0084] In this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or device. Without further limitation, an element defined by the statement "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the said element.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A transmission system, characterized in that, It includes a stator, a rotor, a position detection module and a control module; The rotor has a magnet array, and the magnet array includes a plurality of magnets arranged in sequence along the transmission path; The stator includes a first stator and a second stator. The first stator and the second stator are arranged in sequence along the transmission direction and there is a gap between them. The gap has a first gap edge and a second gap edge arranged in sequence along the transmission direction. Both the first stator and the second stator have stator coils, and the rotor can move relative to the stator along the transmission path under the interaction of the stator coils and the magnet array; The position detection module is used for: Sending a second position signal when it detects that the rotor is between a second preset position and a third preset position; The control module is used for: When the rotor crosses the gap, according to the real-time position of the rotor detected by the position detection module, controlling the first current and / or the second current so that the difference between the actual speed of the rotor at any position when crossing the gap and the preset speed at the corresponding position is less than a set error; According to the second position signal, controlling the first current to gradually decrease, and controlling the second current to gradually increase after being equal to the first current, and controlling the speed of decreasing the first current to be greater than the speed of increasing the second current; And Controlling the first current and the second current so that the rotor moves with uniform acceleration between the first preset position and the second preset position, moves at a constant speed between the second preset position and the third preset position, and moves with uniform deceleration between the third preset position and the fourth preset position; Wherein, the first current is the current applied to the stator coil of the first stator, the second current is the current applied to the stator coil of the second stator, the first preset position and the second preset position are the positions where the rotor is when its head end is flush with the first gap edge and when it is flush with the second gap edge in sequence, and the third preset position and the fourth preset position are the positions where the rotor is when its tail end is flush with the first gap edge and when it is flush with the second gap edge in sequence.

2. The transmission system according to claim 1, wherein The position detection module is used for: Sending a first position signal when it detects that the rotor is between the first preset position and the second preset position; and Sending a third position signal when it detects that the rotor is between the third preset position and the fourth preset position; The control module is used for: Controlling the first current according to the first position signal; and Controlling the second current according to the third position signal.

3. The transmission system according to claim 2, characterized in that, The first stator is provided with a first workstation, the second stator is provided with a second workstation, and the control module is used for: When the mover moves from the first workstation to the second workstation along the transmission path, the first current and / or the second current are controlled according to the real-time position of the mover detected by the position detection module, so that the difference between the actual speed of the mover at any position between the first workstation and the second workstation and the preset speed at the corresponding position is less than the set error.

4. The transmission system according to claim 3, characterized in that The control module is configured to: When the mover moves from the first workstation to the first preset position, control the first current so that the mover accelerates uniformly to the first set speed and then moves at a constant speed; And When the mover moves from the fourth preset position to the second workstation, control the second current so that the mover accelerates uniformly to the second set speed and then decelerates uniformly to zero.

5. The transmission system according to claim 2, characterized in that, The control module is configured to: Control the first current to gradually increase according to the first position signal; Control the first current to remain unchanged according to the second position signal, and control the second current to be equal to the first current; Control the second current to gradually decrease according to the third position signal.

6. The transmission system according to claim 2, characterized in that, The control module is configured to: Control the first current and / or the second current to make the mover move at a constant speed between the first preset position and the fourth preset position; or, Control the first current and / or the second current to make the mover move with uniform acceleration between the first preset position and the fourth preset position.

7. The transmission system according to claim 1, characterized in that, The control module is configured to: Control the front coil in the transmission system to be energized in advance; and Control the rear coil in the transmission system to be powered off with a delay; Wherein, the front coil is located at the position where the mover is about to arrive, and the rear coil is located at the position where the mover has just passed.

8. The transmission system according to any one of claims 1-7, characterized in that, The length of the gap is less than the length of the magnet array on the mover; And / or, the length of the gap is a multiple of the pole width on the mover; And / or, the mover is covered with the magnets.

9. A control method for a transmission system according to any one of claims 1-8, characterized in that, The method includes: When the mover crosses the gap, control the first current and / or the second current according to the real-time position of the mover, so that the difference between the actual speed of the mover at any position and the preset speed at the corresponding position is less than the set error.

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