Low-voltage self-starting variable-frequency permanent magnet motor

Abstract

The invention belongs to the technical field of permanent magnet motors, and particularly relates to a low-voltage self-starting variable-frequency permanent magnet motor, which comprises a permanent magnet motor, a base and a frequency converter, and is characterized in that the frequency converter is arranged in the permanent magnet motor; the base is fixedly installed at the bottom of the permanent magnet motor, an air blowing mechanism is fixedly installed at the bottom of the base, the air blowing mechanism comprises a cavity, an electric motor, a gear, two push-pull rods and two push-pull plates, the cavity is fixedly installed below the base, the electric motor is fixedly installed on the inner wall of the cavity, and the gear is fixedly installed on the inner wall of the cavity. The gear is fixedly connected with the output end of the electric motor, sliding holes are formed in the left side and the right side of the cavity correspondingly, the two push-pull rods are slidably connected into the sliding holes correspondingly, and the two push-pull plates are connected to the outer ends of the push-pull rods through springs correspondingly. And demagnetization or damage of the permanent magnet motor can be avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of permanent magnet motors, and in particular relates to a low-voltage self-starting variable-frequency permanent magnet motor. Background Art

[0002] The principle of low-voltage self-starting variable frequency permanent magnet motor is based on AC speed regulation technology. The speed and torque of the motor are controlled by changing the power supply frequency. However, demagnetization will occur during the operation of the permanent magnet motor. The main reasons for demagnetization include the following aspects:

[0003] High temperature: The magnetism of permanent magnet materials will decrease as the temperature increases. When the temperature approaches or exceeds its Curie point, the magnetism will be permanently lost. Different permanent magnet materials have different demagnetization temperatures. For example, NdFeB permanent magnet materials will begin to demagnetize after being exposed to 180 degrees Celsius for 20 minutes.

[0004] Vibration and impact: Permanent magnets may be damaged or lose their magnetism when subjected to strong vibration or impact. Modern permanent magnets are generally resistant to vibrations without breaking, but collisions may still cause demagnetization.

[0005] Regarding the above two aspects, the permanent magnet motors currently on the market have their own internal heat dissipation structure, but this can only dissipate heat inside the motor. However, since the bottom of the permanent magnet motor is at a small distance from the ground, heat will accumulate underneath, resulting in insufficient heat dissipation and thus accelerated demagnetization. In addition, the current buffering method for permanent magnet motors is only to use a spring for buffering, which has a poor buffering effect and is also prone to accelerated demagnetization. This phenomenon has become a problem that needs to be solved urgently by people in this field. Summary of the invention

[0006] The object of the present invention is to provide a low-voltage self-starting variable-frequency permanent magnet motor to solve the problems raised in the above background technology.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a low-voltage self-starting variable-frequency permanent magnet motor, comprising a permanent magnet motor, a base and a frequency converter, wherein the frequency converter is arranged inside the permanent magnet motor; the base is fixedly installed on the bottom of the permanent magnet motor, and a blowing mechanism is fixedly installed on the bottom of the base, the blowing mechanism comprises a chamber, an electric motor, a gear, two push-pull rods and two push-pull plates, the chamber is fixedly installed below the base, the electric motor is fixedly installed on the inner wall of the chamber, the gear is fixedly connected to the output end of the electric motor, sliding holes are provided on the left and right sides of the chamber, and the two push-pull rods are respectively slidably connected in the sliding holes, the two push-pull plates are respectively spring-connected to the outer ends of the push-pull rods, and a plurality of tooth blocks are provided on the inner sides of the two push-pull rods, which are respectively meshed with the gears through the tooth blocks.

[0008] The present invention further describes that four buffer cavities are arranged around the bottom of the base, and the inner walls of the four buffer cavities are slidably connected with buffer plates, a buffer rod is fixed to the upper surface of the buffer plate, and the upper end of the buffer rod is fixed to the bottom surface of the base, and a buffer spring is fixed between the bottom of the buffer plate and the bottom of the inner wall of the buffer cavity.

[0009] The present invention further illustrates that hydraulic cavities are fixed on both sides of the inner wall of the chamber, and the inner wall of the hydraulic cavity is slidably connected with a hydraulic plate. The inner side of the hydraulic plate is filled with hydraulic oil, and the two hydraulic plates are respectively fixed to two push-pull rods. The inner side of the hydraulic cavity on the left is connected to the bottom pipes of the two buffer cavities on the left, and the inner side of the hydraulic cavity on the right is connected to the bottom pipes of the two buffer cavities on the right, and two holes are arranged on the surface of the buffer plate.

[0010] The present invention further describes that a sphere is fixed between the two buffer cavities on the left and the two buffer cavities on the right, and arc blocks are fixed at the bottom ends of the two push-pull plates.

[0011] The present invention further illustrates that after all the hydraulic oil in the hydraulic chamber enters the buffer chamber and the push-pull plate is extended, the arc block contacts the left side of the sphere and is engaged with each other.

[0012] The present invention further describes that an intelligent control module is provided inside the electric motor, which is electrically connected to the frequency converter and is used to control the number of counterclockwise rotations and the rotation speed of the electric motor according to the power of the frequency converter, and to reset the electric motor clockwise after the counterclockwise rotation is completed.

[0013] The present invention further illustrates that the operation mode of the intelligent control module is: Q is the real-time counterclockwise rotation number of the electric motor, Q max is the maximum number of counterclockwise rotations of the electric motor, F is the power of the inverter, and F max is the maximum power of the inverter; Q is the speed of the electric motor rotating counterclockwise, Q max It is the maximum speed of the electric motor's counterclockwise rotation; the greater the power of the inverter, the greater the number of counterclockwise rotations of the electric motor and the faster the counterclockwise rotation speed.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention uses a frequency converter to accurately control the speed of the permanent magnet motor, reduce energy waste, and is used in occasions requiring high-precision control. It is suitable for different loads and working environments and has good stability and reliability. When the permanent magnet motor is running, in order to avoid demagnetization, it is necessary to dissipate heat and cool the permanent magnet motor in all directions. A heat dissipation device is originally provided inside the permanent magnet motor, and the push-pull plate is driven to move outward at the bottom of the permanent magnet motor by driving the electric motor to run, so as to discharge the hot air at the bottom, thereby playing the role of dissipating heat at the bottom of the permanent magnet motor, which can fully slow down the demagnetization and increase the service life of the motor.

[0015] When the permanent magnet motor vibrates, a reaction force is generated by the buffer spring, thereby playing a buffering role and protecting the permanent magnet motor. At the same time, when the push-pull plate moves left and right to dissipate heat from the bottom of the motor, the hydraulic oil enters the buffer cavity through the pipeline. When the buffer plate slides downward along the inner wall of the buffer cavity, the hydraulic oil is squeezed, and the hydraulic oil enters the top of the buffer plate through the hole, thereby unloading the buffer plate, further improving the buffering effect, playing a full shock-absorbing role, and the heat dissipation process is uninterrupted, thereby performing double buffering through the hydraulic oil and the buffer spring, fully protecting the motor and preventing it from being demagnetized by vibration and affecting the life of the motor;

[0016] When the push-pull plate is extended for a short length, the hydraulic plate is buffered when it slides inward along the inner wall of the hydraulic cavity at a faster speed, thereby preventing the hydraulic oil from instantly and quickly entering the buffer cavity and causing the hydraulic oil to exert an upward force on the buffer plate, and preventing the buffer plate from being subjected to a hard force when moving downward to reduce the buffer effect. When the push-pull plate is extended for a long length, the push-pull plate is quickly reset, thereby quickly introducing external airflow into the bottom of the motor, thereby further enhancing the heat dissipation effect of the bottom of the motor. The overall structure is simple and the cost is low, and it is suitable for all permanent magnet motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 It is a front view of the present invention;

[0020] Figure 3 It is a plan view schematic diagram of the blowing mechanism of the present invention;

[0021] Figure 4 It is a schematic diagram of the internal structure of the buffer cavity of the present invention;

[0022] Figure 5It is a schematic diagram of the internal structure of the chamber of the present invention;

[0023] Figure 6 It is a schematic diagram of the state change of the push-pull plate of the present invention when it is extended long or extended short;

[0024] Figure 7 It is a schematic diagram of the hydraulic oil of the present invention before and after entering the buffer chamber;

[0025] In the figure: 1, permanent magnet motor; 2, base; 21, chamber; 211, electric motor; 212, gear; 213, push-pull rod; 214, push-pull plate; 22, buffer chamber; 221, buffer plate; 222, buffer rod; 223, buffer spring; 224, hole; 23, hydraulic chamber; 231, hydraulic plate; 24, sphere; 25, arc block. DETAILED DESCRIPTION

[0026] The following is a further non-limiting detailed description of the technical solution of the present invention in conjunction with the preferred embodiments and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] See also Figure 1-7 , the present invention provides a technical solution: a low-voltage self-starting variable-frequency permanent magnet motor, comprising a permanent magnet motor 1, a base 2 and a frequency converter, the frequency converter being arranged inside the permanent magnet motor 1;

[0028] The base 2 is fixedly installed at the bottom of the permanent magnet motor 1, and a blowing mechanism is fixedly installed at the bottom of the base 2, the blowing mechanism includes a chamber 21, an electric motor 211, a gear 212, two push-pull rods 213 and two push-pull plates 214, the chamber 21 is fixedly installed below the base 2, the electric motor 211 is fixedly installed on the inner wall of the chamber 21, the gear 212 is fixedly connected to the output end of the electric motor 211, the left and right sides of the chamber 21 are provided with sliding holes, and the two push-pull rods 213 are respectively slidably connected in the sliding holes, the two push-pull plates 214 are respectively spring-connected to the outer ends of the push-pull rods 213, and the inner sides of the two push-pull rods 213 are provided with a plurality of tooth blocks, which are respectively meshed with the gears 212 through the tooth blocks;

[0029] The permanent magnet motor runs, and the power supply frequency is changed through AC speed regulation technology to control the speed and torque of the permanent magnet motor 1. The first step is rectification, which converts the input AC power into DC power, and then filtering, which filters the DC power to make the current smoother. The speed of the permanent magnet motor 1 is controlled by converting the DC power into adjustable frequency AC power, and the power supply frequency and voltage are adjusted by the controller to achieve precise control of the speed and torque of the permanent magnet motor 1. The built-in protection circuit monitors the current, voltage, temperature and other indicators of the permanent magnet motor 1 to ensure the safe operation of the equipment. By accurately controlling the speed of the permanent magnet motor 1, energy waste is reduced. It is used in occasions requiring high-precision control and is suitable for different loads and working environments. It has good stability and reliability. When the permanent magnet motor 1 is running, in order to avoid demagnetization, it is necessary to dissipate heat and cool the permanent magnet motor in all directions. A heat dissipation device is originally provided inside it, and at its bottom, the electric motor 211 is driven to run, driving the gear 212 to rotate. The gear 212 drives the two push-pull rods 213 to move outward through meshing, thereby driving the push-pull plate 214 to move outward, and the hot air at the bottom is discharged, thereby playing the role of dissipating heat from the bottom of the permanent magnet motor, which can fully slow down the demagnetization and increase the service life of the motor.

[0030] Four buffer cavities 22 are arranged around the bottom of the base 2, and the inner walls of the four buffer cavities 22 are slidably connected with buffer plates 221. A buffer rod 222 is fixed to the upper surface of the buffer plate 221, and the upper end of the buffer rod 222 is fixed to the bottom surface of the base 2, and a buffer spring 223 is fixed between the bottom of the buffer plate 221 and the bottom of the inner wall of the buffer cavity 22.

[0031] Hydraulic chambers 23 are fixed on both sides of the inner wall of the chamber 21. A hydraulic plate 231 is slidably connected to the inner wall of the hydraulic chamber 23. The inner side of the hydraulic plate 231 is filled with hydraulic oil, and the two hydraulic plates 231 are respectively fixed to the two push-pull rods 213. The inner side of the left hydraulic chamber 23 is connected to the bottom pipes of the two buffer chambers 22 on the left, and the inner side of the right hydraulic chamber 23 is connected to the bottom pipes of the two buffer chambers 22 on the right. Two holes 224 are arranged on the surface of the buffer plate 221.

[0032] The permanent magnets in the permanent magnet motor may be damaged or lose their magnetism when subjected to strong vibration or impact. At this time, when the permanent magnet motor 1 vibrates, the buffer rod 222 drives the buffer plate 221 to slide downward along the inner wall of the buffer chamber 22 through the base 2, and the buffer spring 223 generates a reaction force, thereby playing a buffering role to protect the permanent magnet motor. At the same time, when the push-pull plate 214 moves left and right to dissipate heat from the bottom of the motor, the push-pull rod 213 drives the hydraulic plate 231 to slide along the inner wall of the hydraulic chamber 23, and the hydraulic oil on the inner side of the hydraulic plate 231 is squeezed and enters the buffer chamber 22 through the pipeline. At this time, the push-pull plate 214 is in an extended state. When the buffer plate 221 slides downward along the inner wall of the buffer chamber 22, the hydraulic oil is squeezed, and the hydraulic oil enters the top of the buffer plate 221 through the hole 224, thereby unloading the buffer plate 221, further improving the buffering effect, and playing a full shock-absorbing role.

[0033] The heat dissipation process is uninterrupted, so that double buffering is performed through the hydraulic oil and the buffer spring 223, which fully protects the motor and prevents it from being vibrated and accelerating demagnetization to affect the life of the motor.

[0034] A sphere 24 is fixed between the two buffer cavities 22 on the left and the two buffer cavities 22 on the right, and an arc block 25 is fixed at the bottom end of the two push-pull plates 214 .

[0035] After all the hydraulic oil in the hydraulic chamber 23 enters the buffer chamber 22 and the push-pull plate 214 is extended, the arc block 25 contacts the left side of the sphere 24 and engages with each other;

[0036] When the push-pull plate 214 is extended to a short length, the push-pull plate 214 collides with the ball 24 after being extended, and the ball 24 generates a reaction force on the push-pull plate 214. The push-pull plate 214 applies a buffering force to the push-pull rod 213 through the spring, so that the hydraulic plate 231 is buffered when sliding inward along the inner wall of the hydraulic chamber 23 at a fast speed, so as to prevent the hydraulic oil from entering the buffer chamber 22 instantly and quickly, causing the hydraulic oil to generate an upward force on the buffer plate 221, and preventing the buffer plate 221 from being subjected to a hard force when moving downward to reduce the buffer effect;

[0037] When the push-pull plate 214 is extended to a long length, the hydraulic oil first quickly and then slowly enters the buffer chamber 22 for buffering and shock absorption. At the same time, due to the increase in the buffering strength, the up and down fluctuation amplitude of the buffer rod 222 is reduced. At this time, the push-pull plate 214 is squeezed by the arc block 25 at the bottom and the sphere 24, so that the arc block 25 presses over the sphere 24. Since the up and down fluctuation amplitude of the buffer rod 222 is small at this time, the fluctuation of the base 2 is reduced accordingly, thereby reducing the up and down fluctuation of the push-pull plate 214, and the sphere 24 can clamp the arc block 25. Later, when the push-pull plate 214 is reset, the push-pull plate 214 is stuck, the spring is deformed by tension, the hydraulic oil in the buffer chamber 22 is extracted, the buffering strength is reduced, the up and down fluctuation amplitude of the buffer rod 222 is increased, the sphere 24 is out of contact with the arc block 25 of the push-pull plate 214, and the spring generates a reaction force to pull the push-pull plate 214 to quickly reset, thereby quickly introducing external airflow into the bottom of the motor, thereby further enhancing the heat dissipation effect at the bottom of the motor.

[0038] An intelligent control module is provided inside the electric motor 211, which is electrically connected to the frequency converter and is used to control the number of counterclockwise rotations and the rotation speed of the electric motor 211 according to the power of the frequency converter, and to reset the electric motor 211 clockwise after the counterclockwise rotation is completed.

[0039] The operation mode of the intelligent control module is:

[0040] Q is the real-time counterclockwise rotation number of the electric motor 211, Q max is the maximum number of counterclockwise rotations of the electric motor 211, F is the power of the inverter, and F max is the maximum power of the inverter;

[0041] Q is the speed at which the electric motor 211 rotates counterclockwise, Q max is the maximum speed of the electric motor 211 rotating counterclockwise;

[0042] The greater the power of the frequency converter, the greater the number of counterclockwise rotations of the electric motor 211 and the faster the counterclockwise rotation speed;

[0043] The greater the power of the inverter, the greater the speed of the permanent magnet motor, and the higher the temperature generated, which increases the number of counterclockwise rotations of the electric motor 211 and speeds up the speed, thereby increasing the speed of left and right movement of the push-pull plate 214, accelerating heat dissipation, and fully avoiding motor damage. Conversely, while ensuring heat dissipation, it reduces energy consumption and saves costs.

[0044] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0045] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents, and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-voltage self-starting variable-frequency permanent magnet motor, comprising a permanent magnet motor (1), a base (2) and a frequency converter, characterized in that: The frequency converter is arranged inside the permanent magnet motor (1); The base (2) is fixedly mounted on the bottom of the permanent magnet motor (1), and a blowing mechanism is fixedly mounted on the bottom of the base (2), the blowing mechanism comprising a chamber (21), an electric motor (211), a gear (212), two push-pull rods (213) and two push-pull plates (214); the chamber (21) is fixedly mounted below the base (2); the electric motor (211) is fixedly mounted on the inner wall of the chamber (21); the gear (212) is fixedly connected to the output end of the electric motor (211); sliding holes are provided on the left and right sides of the chamber (21), and the two push-pull rods (213) are respectively slidably connected in the sliding holes; the two push-pull plates (214) are respectively spring-connected to the outer ends of the push-pull rods (213); a plurality of tooth blocks are provided on the inner sides of the two push-pull rods (213), and the two push-pull rods (213) are respectively meshed with the gears (212) through the tooth blocks.

2. A low-voltage self-starting variable-frequency permanent magnet motor according to claim 1, characterized in that: Four buffer cavities (22) are arranged around the bottom of the base (2); the inner walls of the four buffer cavities (22) are slidably connected with buffer plates (221); a buffer rod (222) is fixed to the upper surface of the buffer plate (221); the upper end of the buffer rod (222) is fixed to the bottom surface of the base (2); and a buffer spring (223) is fixed between the bottom of the buffer plate (221) and the bottom of the inner wall of the buffer cavity (22).

3. A low-voltage self-starting variable-frequency permanent magnet motor according to claim 2, characterized in that: Hydraulic chambers (23) are fixed on both sides of the inner wall of the chamber (21); the inner wall of the hydraulic chamber (23) is slidably connected to a hydraulic plate (231); the inner side of the hydraulic plate (231) is filled with hydraulic oil, and the two hydraulic plates (231) are respectively fixed to two push-pull rods (213); the inner side of the left hydraulic chamber (23) is connected to the bottom pipes of the two buffer chambers (22) on the left, and the inner side of the right hydraulic chamber (23) is connected to the bottom pipes of the two buffer chambers (22) on the right; and two holes (224) are provided on the surface of the buffer plate (221).

4. A low-voltage self-starting variable-frequency permanent magnet motor according to claim 3, characterized in that: A sphere (24) is fixed between the two buffer cavities (22) on the left and the two buffer cavities (22) on the right, and an arc block (25) is fixed at the bottom ends of the two push-pull plates (214).

5. A low-voltage self-starting variable-frequency permanent magnet motor according to claim 4, characterized in that: After all the hydraulic oil in the hydraulic chamber (23) enters the buffer chamber (22) and the push-pull plate (214) is extended, the arc block (25) contacts the left side of the sphere (24) and they are locked with each other.

6. A low-voltage self-starting variable-frequency permanent magnet motor according to claim 5, characterized in that: An intelligent control module is provided inside the electric motor (211), the intelligent control module is electrically connected to the frequency converter, and is used to control the number of counterclockwise rotations and the rotation speed of the electric motor (211) according to the power of the frequency converter, and to reset the electric motor (211) by rotating clockwise after the counterclockwise rotation is completed.

7. A low-voltage self-starting variable-frequency permanent magnet motor according to claim 6, characterized in that: The operation mode of the intelligent control module is: Q is the real-time counterclockwise rotation number of the electric motor (211), Q max is the maximum number of counterclockwise rotations of the electric motor (211), F is the power of the frequency converter, and F max is the maximum power of the inverter; Q is the speed of the electric motor (211) rotating counterclockwise, Q max is the maximum speed of the electric motor (211) rotating counterclockwise; The greater the power of the frequency converter, the greater the number of counterclockwise rotations of the electric motor (211), and the faster the counterclockwise rotation speed.

Images