CN209731028U - Ultrahigh speed magneto - Google Patents

Abstract

The utility model discloses an ultra-high-speed permanent magnet motor, which comprises a casing, a protective cover arranged in the casing, a mandrel, and a double-row cylindrical roller bearing. The protective cover is provided with a solid permanent magnet, the protective cover and the The mandrel is an integral structure, and the double-row cylindrical roller bearing is assembled on the mandrel. On the inner wall of the inwardly convex part of the shell. Aiming at the defects of the traditional rotor structure, the utility model provides an ultra-high-speed permanent magnet motor with small outer diameter of the rotor, good concentricity, high rotation precision, high power density and good high-speed operation performance.

Description

Ultra High Speed Permanent Magnet Motor

technical field

The utility model relates to the technical field of electric power transmission, in particular to an ultra-high-speed permanent magnet motor.

Background technique

High-speed motors have the characteristics of high power density, small moment of inertia, and can directly drive loads. As the core components of high-speed transmission systems, the structure, efficiency, reliability, and precision of motors determine the overall performance of high-speed transmission systems. Traditional high-speed motor rotor structures mainly include surface mount type and three-stage type, as shown in Figure 1 and Figure 2 respectively. The surface mount motor rotor structure consists of a permanent magnet, a mandrel and a protective sleeve. The rotor structure of the three-stage motor consists of a permanent magnet, a protective sleeve and two end shafts, and the two end shafts and the permanent magnet are connected together through the interference fit of the protective sleeve. However, both rotors have disadvantages brought about by their structural characteristics.

The main disadvantages of the surface mount structure are:

1. In order to generate the same magnetic flux, compared with the rotor with solid permanent magnet structure, the outer diameter of the rotor with surface-mounted rotor structure is larger. The increase of the outer diameter of the rotor will make the problems of rotor strength, wind mill loss and temperature rise of high-speed motors more prominent;

2. Wind mill loss and rotor eddy current loss will cause the temperature of the rotor to rise. However, materials commonly used as mandrels, such as titanium alloys, Inconel718, 40CrNiMoA, etc., have higher thermal expansion coefficients than commonly used permanent magnet materials, such as samarium cobalt and neodymium iron boron. Therefore, when the temperature rises, the permanent magnet of the surface-mounted structure will bear the extra tensile stress caused by the rapid expansion of the mandrel, which will make the protection of the permanent magnet more difficult.

The main disadvantages of the three-stage structure are:

1. The thermal expansion coefficient of the mandrel parts on both sides is usually higher than that of the middle permanent magnet. When the temperature rises due to windmill loss and rotor eddy current loss, the material of the mandrel on both sides expands faster than the middle permanent magnet material, which will Cause the sheath to reduce the protection ability of the permanent magnet;

2. In the three-stage structure, the connection between the mandrels on both sides and the permanent magnet in the middle needs to ensure high concentricity, which requires extremely high processing and assembly of parts, which greatly increases the difficulty of processing and assembly. If the assembly accuracy of the three-stage structure is not high, it will seriously affect the performance of the motor at high speed.

Contents of the invention

Purpose of the invention: The technical problem to be solved by this utility model is to provide an ultra-high-speed permanent magnet motor. Aiming at the defects of the traditional rotor structure, it provides a rotor with small outer diameter, good concentricity, high rotation accuracy, high power density, and high-speed operation. Super high speed permanent magnet motor with good performance.

Technical solution: The ultra-high-speed permanent magnet motor described in the utility model includes a casing, a protective sleeve arranged in the casing, a mandrel, and a double-row cylindrical roller bearing. A solid permanent magnet is arranged in the protective casing to protect The sleeve and the mandrel are an integral structure, the double-row cylindrical roller bearing is assembled on the mandrel, the inner wall of the casing is provided with an inwardly protruding structure, and the outer wall of the double-row cylindrical roller bearing is installed on the casing toward the On the inner wall of the inner raised part.

Further, the double-row cylindrical roller bearing includes an outer ring, an inner ring, cylindrical rollers and a cage, the inner ring is installed in cooperation with the mandrel, and the outer ring is bonded to the casing by interference fit or adhesion On the inner wall, the cylindrical roller is installed between the outer ring and the inner ring, and a cage is provided on the side of the cylindrical roller.

Further, the ultra-high-speed permanent magnet motor is an axially symmetrical structure centered on a double-row cylindrical roller bearing, and the two sides of the protective sleeve are equipped with sealed shafts as mechanical output ports.

In order to facilitate the discharge of gas from the blind hole during the assembly of the solid permanent magnet and facilitate the heat dissipation of the rotor, several axial exhaust holes are arranged on the inner side of the protective cover.

Further, the protective sleeve is a hollow cylinder, which is interference-fitted with the solid permanent magnet.

Further, the protective sheath and the mandrel are of integral structure, and the material is inconel 718 or titanium alloy.

Further, the stator in the motor adopts a slotless structure, and the armature winding in the motor is wound annularly inside and outside the stator.

Beneficial effects: the utility model has the following technical effects:

1. The solid permanent magnet structure is adopted to reduce the outer diameter of the rotor, thereby reducing the problems of rotor strength and wind grinding loss caused by the high-speed rotation of the motor. The solid permanent magnet and the sheath are directly interference fit, and when the temperature of the rotor rises, there is no problem of increased rotor stress caused by the rapid expansion of the mandrel;

2. The motor is a centrally symmetrical structure with double permanent magnets, double armature windings, and double mechanical output ports. It operates efficiently, has good balance and stability, and has high output power;

3. The overall structure of the protective sleeve-mandrel avoids the problems of poor assembly accuracy and dispersion of expansion stress caused by multiple nesting of permanent magnets, protective sleeves, and mandrels, and greatly reduces the problems caused by processing and assembly. The tolerance ensures the rotation accuracy. The outer ring of the bearing is directly matched with the casing to form a whole, which has the characteristics of firm assembly and good heat dissipation performance, which improves the service life of the product; the design of the overall rotor structure reduces the product size and expands the application range under the same output performance. .

Description of drawings

Fig. 1 is a structural schematic diagram of an existing surface-mounted high-speed motor;

Fig. 2 is a structural schematic diagram of an existing three-stage high-speed motor;

Fig. 3 is the structural representation of the ultra-high-speed permanent magnet motor of the present utility model;

Fig. 4 is a sectional view of the overall structure of the protective sleeve and the mandrel of the present invention.

Detailed ways

The ultra-high-speed permanent magnet motor of this embodiment is shown in FIG. 3 , and includes casings 7 with inner walls protruding inward on both sides of the middle, and double-row cylindrical roller bearings are directly installed on the inner walls of the inwardly convex parts of the casing 7 . The double-row cylindrical roller bearing adopts double-row steel cylindrical rolling elements, including an outer ring 10 , an inner ring 12 , cylindrical rollers 11 , and a cage 8 . The cylindrical rollers are arranged in parallel, there may be several, and they can rotate around the mandrel 13 between the outer ring 10 and the inner ring 12 . A cage 8 is installed between the cylindrical rollers 11, and the cage 8 is filled with high-speed lubricating grease. The bearing outer ring 10 of the double-row cylindrical roller bearing is installed in cooperation with the inner wall of the inwardly protruding part of the casing 7 , and the outer ring 10 can be attached to the casing 7 through interference fit or adhesion. The ultra-high-speed permanent magnet motor is axially symmetrical with double-row cylindrical roller bearings as the center. Protective sheath 4 is positioned at the both sides of mandrel 13 and is arranged symmetrically, and mandrel 13 is integral structure, and the material of integral structure adopts non-magnetic conduction, the material of high tensile strength, as: any one of inconel 718, titanium alloy. The double-row cylindrical roller bearing is assembled on the outer side of the mandrel 13, and the mandrel 13 and the inner ring 12 are installed in cooperation. With double-row cylindrical roller bearings as the center, the ultra-high-speed permanent magnet motor also includes two sets of symmetrical solid permanent magnets 5, two sets of symmetrical stators 2, two sets of symmetrical armature windings 3, and two sets of symmetrical sealed shafts 1. The solid permanent magnet 5 is arranged inside the protective cover 4, and the two perform interference fit. Preferably, the solid permanent magnet 5 is cylindrical, and the protective cover 4 is a hollow cylindrical structure adapted to the solid permanent magnet 5 . The outer sides of the protective sleeves 4 on both sides are interference-fitted with the sealing shaft 1 and pass through the end cover 6 to serve as mechanical output ports on both sides of the motor. The stator 2 is arranged on the inner wall of the casing 7. The stator 2 can be a slotted stator or a slotless stator. When a slotted stator is used, the armature winding 3 is wound in the slot of the stator 2. When a slotless stator is used, The armature winding 3 is wound annularly inside and outside the stator 2 . The armature winding 3 is located on the periphery of the solid permanent magnet 5 .

As shown in FIG. 4 , several axial exhaust holes 9 are provided on the inner side of the protective cover 4 close to the mandrel 13 , generally 3 to 5, for exhausting gas from blind holes during the assembly process of the solid permanent magnet 5 .

In the technical scheme of the utility model, a cylindrical solid permanent magnet is used to integrate the protective sleeve and the mandrel into an integral structure. The problems of poor assembly accuracy and dispersion of expansion stress caused by the multiple nesting of magnets, protective sleeves, mandrels, and bearings can improve the performance of the motor at high speed. The double-row cylindrical roller bearing is assembled with the symmetrical rotor structure, which has the advantages of compact structure, high rigidity and large bearing capacity. The outer ring of the bearing is in direct contact with the casing, and the contact area is large, which greatly improves the heat dissipation performance and the service life of the motor. The motor is a centrally symmetrical structure with double permanent magnets, double armature windings, and double mechanical output ports. It operates efficiently, has good balance and stability, and has high output power.

Claims (7)

1. a super high-speed permanent magnet motor, comprising casing (7), protective cover (4), mandrel (13), double row cylindrical roller bearing that are arranged on the casing (7), described protective cover ( 4) is provided with a solid permanent magnet (5), the protective cover (4) and the mandrel (13) are an integral structure, and the double-row cylindrical roller bearing is assembled on the mandrel (13), which is characterized in that: the casing (7) The inner wall is provided with an inward protruding structure, and the outer wall of the double-row cylindrical roller bearing is installed on the inner wall of the inward protruding part of the casing (7). 2. The ultra-high-speed permanent magnet motor according to claim 1, characterized in that: the double-row cylindrical roller bearing comprises an outer ring (10), an inner ring (12), cylindrical rollers (11) and a cage (8), the inner ring (12) is installed in cooperation with the mandrel (13), the outer ring (10) is adhered to the inner wall of the casing (7) through interference fit or sticking, and the cylindrical roller (11 ) is installed between the outer ring (10) and the inner ring (12), and a cage (8) is provided on the side of the cylindrical roller (11). 3. The ultra-high-speed permanent magnet motor according to any one of claims 1 and 2, characterized in that: the ultra-high-speed permanent magnet motor is an axially symmetrical structure centered on a double-row cylindrical roller bearing, and the Both sides of the protective sleeve (4) are equipped with sealed shafts (1) as mechanical output ports. 4. The ultra-high-speed permanent magnet motor according to claim 3, characterized in that: several axial exhaust holes (9) are arranged on the inner side of the protective cover (4). 5. The ultra-high-speed permanent magnet motor according to claim 3, characterized in that: the protective sleeve (4) is a hollow cylinder, and is interference-fitted with the solid permanent magnet (5). 6. The ultra-high-speed permanent magnet motor according to claim 3, characterized in that: the protective sleeve (4) and the mandrel (13) are of integral structure, and the material of the integral structure is inconel 718 or titanium alloy. 7. The ultra-high-speed permanent magnet motor according to claim 3, characterized in that: the stator (2) in the motor adopts a slotless structure, and the armature winding (3) in the motor is in the stator, Ring wrapping on the outside.