Rotor integral magnetization alignment device and method for permanent magnet motor

Abstract

The present invention discloses a rotor integral magnetization alignment device for a permanent magnet motor, comprising a rotor body, a positioning part provided on the rotor body, a lifting and rotating mechanism, a pressing mechanism arranged above the lifting and rotating mechanism, and a magnetization coil and an alignment point arranged between the lifting and rotating mechanism and the pressing mechanism; a position sensor is also installed at the alignment point. The alignment device aligns the positioning part of the rotor body through the position sensor without positioning it, allowing the rotor body to shift, and thus will not hinder the rotation or jumping of the rotor body like a positioning pin, thereby avoiding damage to the rotor body. At the same time, an alignment method is also provided, which magnetizes the rotor body by a step-by-step magnetization method, which can improve the alignment accuracy and ensure the magnetization efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of rotor magnetization, and in particular to a rotor integral magnetization alignment device and method for a permanent magnet motor. Background Art

[0002] The overall magnetization of the rotor of a permanent magnet motor is to make each magnetic pole in the rotor correspond to a coil, and magnetize the magnets in all the magnetic poles of the entire rotor at one time. The core technology is that the magnetization coil corresponds to the position of the rotor magnetic pole, especially for skewed and staggered rotors, and the customized coils must also be made into skewed and staggered structures. During magnetization, a high-voltage power supply is used to discharge the coil instantly, and a large current is passed in a short time, generating a strong magnetic field in the coil to magnetize the magnetic steel in the rotor magnetic pole.

[0003] In the actual operation of magnetizing the rotor, the alignment of the rotor and the coil is critical. Since the rotor poles are designed symmetrically, when the alignment is accurate, at the moment of magnetization, the magnetic forces generated by the strong magnetic field will cancel each other out in the circumferential direction and in the axial direction. However, due to errors in the manufacture, installation and alignment of the coil and rotor during magnetization, the magnetic forces are not completely offset during magnetization, which will generate circumferential torque or axial impact force on the rotor, causing the rotor to rotate or jump. During the magnetization process, the strong magnetic field overcomes the coercive force of the magnetic steel to magnetize the magnetic steel, which is also an empowering process. The magnetization of the permanent magnet motor rotor requires a sufficiently strong magnetic field to complete saturation magnetization. If the rotor rotates or jumps during the magnetization process, there will be energy loss, which is converted into the kinetic energy of the rotor. In severe cases, it will lead to unsaturated magnetization.

[0004] Therefore, it is necessary to accurately position the rotor and restrict its movement. In the prior art, the overall magnetization and alignment of the permanent magnet motor rotor adopts a mechanical positioning method, that is, a positioning pin is aligned in the circumferential direction and inserted into the positioning part of the rotor (such as a positioning hole, a positioning keyway or a reinforcing rib and other characteristic concave and convex points to correspond to their placement angle position) for alignment and positioning. The positioning of the rotor by the positioning pin will withstand the possible torque of the rotor rotation during magnetization, prevent the rotor from moving, and ensure the energy conversion efficiency.

[0005] However, due to the strong magnetic field during magnetization, and the inevitable errors in the manufacturing, installation and alignment of the equipment and rotor before magnetization, if they are not completely aligned, a large torque or impact force will be generated during magnetization. The positioning pin will produce knocking noise when overcoming the torque or impact force, which may damage the rotor. After multiple impacts, the pin may even break and other equipment damage may occur. Summary of the invention

[0006] The purpose of the present invention is to provide a rotor integral magnetization alignment device for a permanent magnet motor, which aligns the positioning part of the rotor body through a position sensor without positioning it, allowing the rotor body to shift, and thus will not hinder the rotation or jumping of the rotor body like a positioning pin, thereby avoiding damage to the rotor body or equipment. At the same time, a positioning method is also provided, which magnetizes the rotor body in a step-by-step magnetization manner, thereby improving the alignment accuracy and ensuring the magnetization efficiency.

[0007] In order to achieve the above purpose, the following technical solutions are adopted:

[0008] A rotor integral magnetizing alignment device for a permanent magnet motor comprises a rotor body, a positioning portion is provided on the rotor body, a lifting and rotating mechanism, a pressing mechanism arranged above the lifting and rotating mechanism, and a magnetizing coil and an alignment point arranged between the lifting and rotating mechanism and the pressing mechanism; a position sensor is also installed at the alignment point; the lifting and rotating mechanism is used to lift the rotor body transferred to the top of the rotor body by an external transfer mechanism to a predetermined position in the magnetizing coil, and cooperate with the pressing mechanism to initially limit and fix the rotor body; the position sensor is used to detect the position of the positioning portion, and the lifting and rotating mechanism is also used to drive the rotor body to rotate so that the positioning portion and the alignment point are initially aligned.

[0009] Furthermore, the position sensor is a photoelectric sensor.

[0010] Furthermore, the lifting and rotating mechanism includes a rotating module, a first lifting module installed on the rotating module, a lifting column drivingly connected to the first lifting module, and an elastic pad installed on the lifting column.

[0011] Furthermore, the pressing mechanism includes a second lifting module, a buffer spring drivingly connected to the second lifting module, and an elastic pressing head installed on the buffer spring.

[0012] Furthermore, pressure sensors are installed on the elastic pad and the elastic pressure head.

[0013] Furthermore, the rotor integral magnetization alignment device of the permanent magnet motor also includes a warning device.

[0014] In order to achieve the above object, a method for magnetizing and aligning the rotor of a permanent magnet motor is also provided, comprising:

[0015] S1: The rotor body is moved to the top of the lifting and rotating mechanism, and the lifting and rotating mechanism drives the rotor body to rise to a predetermined position in the magnetizing coil, and cooperates with the pressing mechanism to initially clamp and fix the rotor body;

[0016] S2: The position of the positioning part on the rotor body is detected by the position sensor, and the lifting and rotating mechanism drives the rotor body to rotate so that the positioning part and the alignment point are preliminarily aligned;

[0017] S3: magnetizing the rotor body with an unsaturated magnetizing voltage, and then correcting the angle deviation between the positioning portion and the alignment point based on the magnetic force, so that the positioning portion and the alignment point are accurately aligned;

[0018] S4: Detecting and recording the pressure change value of the rotor body during unsaturated magnetization based on the pressure sensor, and judging the jumping direction of the rotor body based on the pressure change value, and if the pressure change value exceeds a preset pressure threshold, adjusting the height of the rotor body in the opposite direction according to the jumping direction of the rotor body to ensure that the rotor body is in a predetermined position during magnetization;

[0019] S5: magnetize the rotor body with saturation magnetizing voltage.

[0020] Furthermore, the predetermined position in S1 is a position where the center point of the rotor body in the axial direction and the center point of the magnetizing coil in the axial direction are aligned with each other.

[0021] Furthermore, the unsaturated magnetizing voltage in S3 is between 1 / 5 and 1 / 4 of the saturated magnetizing voltage.

[0022] By adopting the above scheme, the beneficial effects of the present invention are:

[0023] 1) The positioning part of the rotor body is aligned by the position sensor instead of being positioned, so that the rotor body is allowed to shift, and thus it will not hinder the rotation or jumping of the rotor body like the positioning pin, thereby avoiding damage to the rotor body or the equipment;

[0024] 2) An elastic pad is added to the jacking column to buffer the downward impact force when the rotor body is magnetized, ensuring that the rotor body is not easily damaged;

[0025] 3) Pressure sensors are installed on both the elastic pad and the elastic pressure head to detect the pressure change when the rotor body is magnetized, and then determine whether the rotor body has a jump and the direction of the jump, so as to correct its position;

[0026] 4) During magnetization, the rotor body is magnetized in a step-by-step manner, that is, the rotor body is initially magnetized using an unsaturated magnetization voltage, so as to correct the angle deviation between the positioning part and the alignment point with the help of magnetic force, so that the positioning part and the alignment point are accurately aligned, and then the rotor body is magnetized for the second time using a saturated magnetization voltage. Since the positioning part and the alignment point are accurately aligned after the initial magnetization, the magnetic forces cancel each other out during the second magnetization, thereby preventing the rotor body from deviating from the predetermined position due to the influence of the magnetic force, ensuring sufficient magnetization and improving the magnetization efficiency;

[0027] 5) By using an unsaturated magnetizing voltage to perform preliminary magnetization on the rotor body to correct the position of the rotor body, the position deviation caused by the manufacturing error of the rotor body can be reduced, the positioning accuracy can be improved, the energy loss can be reduced, and the impact noise during magnetization can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the present invention;

[0029] Figure 2 It is a flow chart of the alignment method of the present invention;

[0030] The accompanying drawings illustrate:

[0031] 1—lifting and rotating mechanism; 2—pressing mechanism;

[0032] 3—rotor body; 4—magnetizing coil;

[0033] 5—position sensor; 6—pressure sensor;

[0034] 11—first lifting module; 12—lifting column;

[0035] 13—elastic pad; 21—second lifting module;

[0036] 22—buffer spring; 23—elastic pressure head;

[0037] 31—Positioning section. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0039] Reference Figure 1 As shown, the present invention provides a rotor integral magnetizing alignment device for a permanent magnet motor, comprising a rotor body 3, on which a positioning portion 31 is provided, and further comprising a lifting and rotating mechanism 1, a pressing mechanism 2 arranged above the lifting and rotating mechanism 1, and a magnetizing coil 4 and an alignment point arranged between the lifting and rotating mechanism 1 and the pressing mechanism 2; a position sensor 5 is also installed at the alignment point; the lifting and rotating mechanism 1 is used to lift the rotor body 3 transferred to its top by an external transfer mechanism to a predetermined position in the magnetizing coil 4, and cooperate with the pressing mechanism 2 to initially limit and fix the rotor body 3; the position sensor 5 is used to detect the position of the positioning portion 31, and the lifting and rotating mechanism 1 is also used to drive the rotor body 3 to rotate so that the positioning portion 31 and the alignment point are initially aligned.

[0040] Among them, the position sensor 5 is a photoelectric sensor; the lifting and rotating mechanism 1 includes a rotating module, a first lifting module 11 installed on the rotating module, a lifting column 12 driven and connected to the first lifting module 11, and an elastic pad 13 installed on the lifting column 12; the pressing mechanism 2 includes a second lifting module 21, a buffer spring 22 driven and connected to the second lifting module 21, and an elastic pressure head 23 installed on the buffer spring 22; pressure sensors 6 are also installed on the elastic pad 13 and the elastic pressure head 23; the rotor overall magnetization alignment device of the permanent magnet motor also includes a warning device.

[0041] A method for magnetizing and aligning the rotor of a permanent magnet motor is also provided, comprising:

[0042] S1: Move the rotor body 3 to the top of the lifting and rotating mechanism 1, the lifting and rotating mechanism 1 drives the rotor body 3 to rise to a predetermined position in the magnetizing coil 4, and cooperates with the pressing mechanism 2 to initially clamp and fix the rotor body 3;

[0043] S2: The position of the positioning portion 31 on the rotor body 3 is detected by the position sensor 5, and the lifting and rotating mechanism 1 drives the rotor body 3 to rotate so that the positioning portion 31 is preliminarily aligned with the alignment point;

[0044] S3: magnetizing the rotor body 3 with an unsaturated magnetizing voltage, and then correcting the angle deviation between the positioning portion 31 and the alignment point based on the magnetic force, so that the positioning portion 31 and the alignment point are accurately aligned;

[0045] S4: Detecting and recording the pressure change value of the rotor body 3 during unsaturated magnetization based on the pressure sensor 6, and judging the jumping direction of the rotor body 3 based on the pressure change value, and if the pressure change value exceeds a preset pressure threshold, adjusting the height of the rotor body 3 in the opposite direction according to the jumping direction of the rotor body 3 to ensure that the rotor body 3 is in a predetermined position during magnetization;

[0046] S5: magnetizing the rotor body 3 with a saturation magnetizing voltage.

[0047] The predetermined position in S1 is the center point of the rotor body 3 in its axial direction, which is flush with the center point of the magnetizing coil 4 in its axial direction; the unsaturated magnetizing voltage in S3 is between 1 / 5 and 1 / 4 of the saturated magnetizing voltage.

[0048] Working principle of the present invention:

[0049] Continue to refer to Figure 1As shown, in this embodiment, the alignment device may also include a transmission mechanism arranged between the lifting and rotating mechanism 1 and the pressing mechanism 2, which can transmit the rotor bodies 3 that need to be magnetized to the top of the lifting and rotating mechanism 1 one by one (the rotor bodies 3 can also be manually moved to the top of the lifting and rotating mechanism 1, which is not limited here), and then the lifting and rotating mechanism 1 drives the rotor body 3 to rise to a predetermined position in the magnetizing coil 4, and cooperates with the pressing mechanism 2 to initially clamp and fix the rotor body 3; the predetermined position can be the center point of the rotor body 3 in its axial direction, which is at a position that is flush with the center point of the magnetizing coil 4 in its axial direction, and the lifting stroke can be recorded and saved. Each time magnetization is performed, the rotor body 3 can be driven to rise to the same stroke by the lifting and rotating mechanism 1; a position sensor 5 (photoelectric sensor) is provided at the alignment point, which can Detect whether the positioning portion 31 (which may be a positioning hole, a positioning keyway or a characteristic concave-convex point corresponding to its placement angle position) and the alignment point are preliminarily aligned. If there is an angular deviation, the rotor body 3 is driven to rotate by the lifting and rotating mechanism 1 to align the positioning portion 31 with the alignment point, abandoning the conventional method of aligning and positioning the positioning portion 31 by means of a mechanical positioning pin. Only the positioning portion 31 can be aligned without positioning. Therefore, when the rotor body 3 is magnetized, the noise generated by the positioning pin hindering the rotation of the rotor body 3 and the damage to the rotor body 3 can be avoided, thereby improving the safety of operation. At the same time, the alignment device is also provided with a warning device, which may be a buzzer alarm. When the photoelectric sensor fails to sense that the positioning portion 31 is aligned with the alignment point, a warning can be issued so that the staff can continue to adjust the position of the rotor body 3.

[0050] The rotating module and the first lifting module 11 of the lifting and rotating mechanism 1 can be a rotating motor and a lifting motor respectively, which are not limited here, and can drive the rotor body 3 to perform lifting and rotating movements to adjust the position of the rotor body 3. At the same time, an elastic pad 13 is added to the lifting column 12, which can buffer the downward impact force of the rotor body 3 when the rotor body 3 is magnetized to ensure that the rotor body 3 is not easily damaged; the second lifting module 21 of the pressing mechanism 2 can also be a lifting motor, which is not limited here, and can drive the buffer spring 22 and the elastic pressure head 23 to press down the rotor body 3 to preliminarily fix the rotor body 3; the buffer spring 22 and the elastic pressure head 23 both have a certain elastic force, which can buffer the upward impact force of the rotor body 3 to avoid damage; in addition, pressure sensors 6 are installed on the elastic pad 13 and the elastic pressure head 23, which can detect the pressure change of the rotor body 3 when the rotor body 3 is magnetized, and then determine whether the rotor body 3 has a jump and the direction of the jump. If the pressure value exceeds the preset pressure threshold, the height of the rotor body 3 is appropriately adjusted so that the center height of the rotor body 3 is as close to the predetermined height as possible during magnetization.

[0051] When the rotor body 3 is magnetized, it is not positioned, and only the rotor body 3's own inertia, the friction force against the top and the buffer pressure are used to damp the possible rotation or jumping, allowing the rotor body 3 to shift, and thus will not hinder the rotation or jumping of the rotor body 3 like the positioning pin, thereby avoiding damage to the rotor body 3; when magnetizing, the rotor body 3 is magnetized in a step-by-step manner, that is, firstly, the rotor body 3 is preliminarily magnetized with an unsaturated magnetizing voltage, so as to correct the angular deviation between the positioning portion 31 and the alignment point with the help of magnetic force (there may be a certain angular deviation during the preliminary alignment), so that the positioning portion 31 and the alignment point are aligned. The points are precisely aligned, and then the rotor body 3 is magnetized for the second time with a saturation magnetizing voltage (normal magnetizing voltage). After the initial magnetization, the positioning portion 31 is precisely aligned with the alignment point, and when magnetized again, the magnetic forces cancel each other out, thereby preventing the rotor body 3 from deviating from the predetermined position due to the influence of the magnetic force, ensuring sufficient magnetization and improving the magnetization efficiency. In addition, when the rotor bodies 3 are magnetized in batches, the height deviations of multiple rotor bodies 3 after magnetization can be statistically summarized, and if the height deviations all tend to a certain value, the initial position of the rotor body 3 is reversely corrected based on the value before magnetization.

[0052] Based on step-by-step magnetization, the principle of improving the magnetization alignment accuracy is explained as follows:

[0053] Assuming that the original rotor body 3 deviates by 1° in the counterclockwise direction, the direction of the magnetic force is in the clockwise direction. When the unsaturated magnetizing voltage is used for magnetization, the rotor body 3 will be accelerated in the clockwise direction by the magnetic force. However, when the rotor body 3 reaches the counterpoint of magnetic force balance, the magnetic force is only in the radial direction, and there is no component in the circumferential direction, that is, there is no acceleration in the circumferential direction. However, at this time, the rotor body 3 has been accelerated for a period of time, and its speed is not 0. It will continue to move in the clockwise direction across the counterpoint. However, when the rotor body 3 is displaced in the clockwise direction, the component of the magnetic force in the circumferential direction appears again, but the direction of the force changes to the counterclockwise direction, which will decelerate the rotor. At the same time, the rotor moves in the counterclockwise direction. It is also affected by the friction force of the contact part between the lifting and rotating mechanism 1 and the pressing mechanism 2 and the rotor body 3. The friction force and the component of the magnetic force in the circumferential direction together slow down the rotation of the rotor body 3. When the rotation speed of the rotor body 3 is reduced to 0, the rotor body 3 has deviated a short distance in the clockwise direction. The direction of the magnetic force is counterclockwise, which will accelerate the rotor body 3 to rotate counterclockwise, and so on and so forth until the magnetic force disappears or is insufficient to overcome the friction resistance to move the rotor body 3, and then it stops; due to the existence of friction resistance, the distance of this reciprocating motion of the rotor body 3 is gradually reduced, and the position when it finally stops will be closer to the alignment point of the magnetic balance than the original position, thereby improving the alignment accuracy of the rotor body 3.

[0054] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for magnetizing and aligning the rotor of a permanent magnet motor, comprising a device for magnetizing and aligning the rotor of a permanent magnet motor; the device for magnetizing and aligning the rotor of a permanent magnet motor comprises a rotor body, and a positioning portion is provided on the rotor body, and further comprises a lifting and rotating mechanism, a pressing mechanism arranged above the lifting and rotating mechanism, and a magnetizing coil and an alignment point arranged between the lifting and rotating mechanism and the pressing mechanism; a position sensor is also installed at the alignment point; the lifting and rotating mechanism is used to lift the rotor body transferred to the top of the rotor body by an external transfer mechanism to a predetermined position in the magnetizing coil, and cooperate with the pressing mechanism to initially limit and fix the rotor body; the position sensor Used to detect the position of the positioning part, the lifting and rotating mechanism is also used to drive the rotor body to rotate so that the positioning part and the alignment point are preliminarily aligned; the position sensor is a photoelectric sensor; the lifting and rotating mechanism includes a rotating module, a first lifting module installed on the rotating module, a lifting column driven and connected to the first lifting module, and an elastic pad installed on the lifting column; the pressing mechanism includes a second lifting module, a buffer spring driven and connected to the second lifting module, and an elastic pressure head installed on the buffer spring; pressure sensors are also installed on the elastic pad and the elastic pressure head; the rotor integral magnetization alignment device of the permanent magnet motor also includes a warning device, characterized in that, include S1: The rotor body is moved to the top of the lifting and rotating mechanism, and the lifting and rotating mechanism drives the rotor body to rise to a predetermined position in the magnetizing coil, and cooperates with the pressing mechanism to initially clamp and fix the rotor body; S2: The position of the positioning part on the rotor body is detected by the position sensor, and the lifting and rotating mechanism drives the rotor body to rotate so that the positioning part and the alignment point are preliminarily aligned; S3: magnetizing the rotor body with an unsaturated magnetizing voltage, and then correcting the angle deviation between the positioning portion and the alignment point based on the magnetic force, so that the positioning portion and the alignment point are accurately aligned; S4: Detecting and recording the pressure change value of the rotor body during unsaturated magnetization based on the pressure sensor, and judging the jumping direction of the rotor body based on the pressure change value, and if the pressure change value exceeds a preset pressure threshold, adjusting the height of the rotor body in the opposite direction according to the jumping direction of the rotor body to ensure that the rotor body is in a predetermined position during magnetization; S5: magnetize the rotor body with saturation magnetizing voltage.

2. The method for overall magnetization and alignment of the rotor of a permanent magnet motor according to claim 1, characterized in that: The predetermined position in S1 is a position where the center point of the rotor body in the axial direction and the center point of the magnetizing coil in the axial direction are aligned with each other.

3. The method for overall magnetization and alignment of the rotor of a permanent magnet motor according to claim 1, characterized in that: The unsaturated magnetizing voltage in S3 is between 1 / 5 and 1 / 4 of the saturated magnetizing voltage.

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