Motor rotor magnetic isolation bridge nitriding tool

Abstract

The utility model discloses a motor rotor magnetic isolation bridge nitriding tool. The tool comprises a tool base, an end plate and an end plate fixing structure, the tool base is of a cylindrical structure with an opening in the upper portion and a bottom plate at the bottom, the cylindrical structure is internally provided with a containing space for containing a rotor iron core which is coaxially arranged, and a plurality of grooves penetrating through the height of the cylinder wall are evenly formed in the cylinder wall of the cylindrical structure; grooves are formed in the opening end of the tool base, the cylinder wall of the cylindrical structure is divided into a plurality of protection teeth by the grooves, the number of the grooves and the number of the protection teeth are the same as the number of poles of a rotor, the grooves are correspondingly consistent with the magnetic isolation bridge portion of a rotor iron core, and the end plate is a disc capable of being matched with the inner diameter of the opening end of the tool base. The end plate is connected to the open end of the tool base in a matched mode through an end plate fixing structure. The structure is simple, when the rotor iron core is installed in the structure and placed in a nitriding furnace for nitriding treatment, only the magnetic isolation bridge part of the rotor can be nitrided, the magnetic permeability of the rotor is reduced, and the magnetic permeability of other parts is ensured to be unchanged.

Description

Technical Field

[0001] The utility model relates to a tooling for nitriding the magnetic isolation bridge of a motor rotor, belonging to the technical field of motors. Background Art

[0002] The rotor core of an interior permanent magnet motor mainly includes a rotor shaft hole, a rotor magnet slot, a rotor magnetic isolation bridge, a rotor outer circle, etc. Among them, the rotor magnetic bridge is the core part and the main part affecting the efficiency and reliability of the motor. Most of the rotor cores of existing interior permanent magnet motors adopt magnetic isolation bridges. Reducing the width of the magnetic isolation bridge can reduce magnetic leakage, increase back electromotive force, improve efficiency, and reduce noise. However, its width cannot be too small. If the width of the magnetic isolation bridge is less than the lamination thickness, it will affect the mechanical strength of the punching sheet, unable to meet the process requirements, unable to mass-produce, and at the same time affect the reliability of the motor rotor.

[0003] The inventor of the present application has found through research that after nitriding the magnetic isolation bridge of the rotor core of an interior permanent magnet motor, the nitrided magnetic isolation bridge can reduce rotor magnetic leakage, increase back electromotive force, and improve motor efficiency. However, when performing nitriding treatment, how to ensure that only the magnetic isolation bridge part of the rotor core is nitrided without affecting other parts of the rotor core is a key problem that needs to be solved urgently. There is no tooling in the prior art suitable for nitriding the magnetic isolation bridge part of the rotor core. Summary of the Utility Model

[0004] In view of the above defects existing in the prior art, the utility model provides a tooling with a simple structure and suitable for nitriding the magnetic isolation bridge part of the rotor core.

[0005] The utility model is realized through the following technical solutions: A nitriding tooling for the magnetic isolation bridge of a motor rotor, characterized in that: it includes a tooling base, an end plate, and an end plate fixing structure. The tooling base is a cylindrical structure with an open upper part and a bottom plate. There is an accommodation space for accommodating a coaxially arranged rotor core inside the cylindrical structure. A plurality of grooves penetrating the height of the cylinder wall are evenly opened on the cylinder wall of the cylindrical structure. The grooves divide the cylinder wall of the cylindrical structure into a plurality of teeth. The number of the grooves and the teeth is the same as the number of rotor poles, and the grooves correspond to the magnetic isolation bridge part of the rotor core. The end plate is a disc that can be matched with the inner diameter of the open end of the tooling base, and the end plate is connected to the open end of the tooling base through the end plate fixing structure.

[0006] When the utility model is in use, the rotor core is placed in the tooling base, the groove of the tooling base is aligned with the magnetic isolation bridge part of the rotor core, the end plate is placed on the upper part of the rotor core, and the end plate, the rotor core and the tooling base are fixed together through the end plate fixing structure. When nitriding treatment is carried out, the rotor core fixed by the tooling is placed in the nitriding furnace for nitriding. Since the magnetic isolation bridge part of the rotor core is not protected by the guard teeth and the end plate, it will be nitrided. After nitriding treatment, the magnetic resistance of the magnetic bridge increases, which can effectively reduce the rotor magnetic leakage.

[0007] Furthermore, the inner diameter of the cylindrical structure is 0.02 mm - 0.05 mm larger than the outer diameter of the rotor core.

[0008] Furthermore, a round hole is provided at the center of the bottom plate of the tooling base, a threaded hole is provided at the center of the end plate, and the tooling base and the end plate are connected by screws passing through their centers. The end plate and the tooling base can be conveniently connected together by screws.

[0009] Furthermore, a plurality of end plate installation protrusions protruding outward are provided on the outer circumference of the end plate, the end plate installation protrusions correspond to the guard teeth of the tooling base, and an end plate installation groove is provided on the inner side of the guard teeth of the tooling base at the joint with the end plate. The end plate is connected with the end plate installation groove on the inner side of the guard teeth of the tooling base through its end plate installation protrusions.

[0010] The beneficial effects of the utility model are as follows: The structure of the utility model is reasonably designed. When the rotor core is placed in the tooling base, the groove on the tooling base is aligned with the magnetic isolation bridge part of the rotor core, and after the end plate is installed, only the magnetic isolation bridge part of the rotor core is exposed from the groove on the tooling base, and the rest of the rotor core is protected by the guard teeth, the end plate and the bottom plate. When the rotor core installed in the tooling is placed in the nitriding furnace for nitriding treatment, since the magnetic isolation bridge part is not protected by the guard teeth and the end plate, it is nitrided. The utility model has a simple structure, and the installation and removal of the rotor core in the tooling are both simple and convenient; during nitriding treatment in the nitriding furnace, through the tooling, only the magnetic isolation bridge part of the rotor core can be nitrided to reduce its magnetic permeability, while other parts of the rotor core can be reliably protected to ensure that the magnetic permeability of other parts remains unchanged. Description of the Drawings

[0011] Figure 1 is the structural schematic diagram of the utility model in Embodiment 1;

[0012] Figure 2 is the cross-sectional schematic diagram of the utility model in Embodiment 1;

[0013] Figure 3 is the three-dimensional structural schematic diagram of the utility model in Embodiment 1;

[0014] Figure 4 It is the front view schematic diagram of the tooling base in Embodiment 1;

[0015] Figure 5 It is Figure 4 the top view schematic diagram of;

[0016] Figure 6 It is the sectional view schematic diagram of the tooling base in Embodiment 1;

[0017] Figure 7 It is the three-dimensional structure schematic diagram of the tooling base in Embodiment 1;

[0018] Figure 8 It is the end face schematic diagram of the rotor core;

[0019] Figure 9 It is the side view schematic diagram of the rotor core;

[0020] Figure 10 It is the end face schematic diagram of the cooperation between the rotor core and the tooling base in Embodiment 1;

[0021] Figure 11 It is the front view schematic diagram of the end plate in Embodiment 2;

[0022] Figure 12 It is Figure 11 the top view schematic diagram of;

[0023] Figure 13 It is the three-dimensional structure schematic diagram of the end plate in Embodiment 2;

[0024] Figure 14 It is the front view schematic diagram of the tooling base in Embodiment 2;

[0025] Figure 15 It is Figure 14 the top view schematic diagram of;

[0026] Figure 16 It is the sectional view schematic diagram of the tooling base in Embodiment 2;

[0027] Figure 17 It is the three-dimensional structure schematic diagram of the tooling base in Embodiment 2;

[0028] Figure 18 It is the schematic diagram of the cooperation between the rotor core and the tooling in Embodiment 2;

[0029] In the figure, 1. tooling base, 2. rotor core, 3. end plate, 4. screw;

[0030] 1.1. round hole at the center of the bottom plate, 1.2. protective teeth, 1.3. groove, 1.4. bottom plate, 1.5. end plate installation groove;

[0031] 2.1, Magnetic isolation bridge; 2.2, Shaft hole; 2.3, Magnet slot; 2.4, Outer circle of iron core;

[0032] 3.1, End plate mounting protrusion. Specific implementation mode

[0033] The following is a further description of the present utility model through non-limiting embodiments in conjunction with the drawings:

[0034] Embodiment 1

[0035] As shown in the attached Figures 1 - 7 figure, a nitriding tooling for the magnetic isolation bridge of a motor rotor includes a tooling base 1, an end plate 3, and an end plate fixing structure. The tooling base 1 is a cylindrical structure with an open upper part and a bottom plate 1.4 at the bottom. A circular hole 1.1 is provided at the center of the bottom plate 1.4. An accommodation space for accommodating a coaxially arranged rotor iron core is provided inside the cylindrical structure. A plurality of grooves 1.3 penetrating the height of the cylindrical wall are evenly opened on the cylindrical wall of the cylindrical structure. The grooves 1.3 divide the cylindrical wall of the cylindrical structure into a plurality of guard teeth 1.2. The number of the grooves 1.3 and the guard teeth 1.3 is the same as the number of rotor poles, and the grooves 1.3 correspond to the magnetic isolation bridge parts of the rotor iron core. The end plate 3 is a disc that can be matched with the inner diameter of the open end of the tooling base 1. A threaded hole is provided at the center of the end plate 3. The end plate fixing structure includes a screw 4. The screw 4 can pass through the circular hole 1.1 at the center of the bottom plate of the tooling base 1 and be connected to the threaded hole at the center of the end plate 3.

[0036] To facilitate the removal of the rotor iron core from the tooling base 1, a clearance fit is adopted between the rotor iron core and the tooling base. Preferably, the inner diameter of the cylindrical structure is 0.02 mm - 0.05 mm larger than the outer diameter of the rotor iron core.

[0037] In this embodiment, the tooling base 1 is provided with 6 grooves 1.3 and 6 guard teeth 1.2, and the grooves 1.3 and the guard teeth 1.2 are evenly arranged at intervals.

[0038] As shown in the attached Figures 8 - 9 figure is a schematic diagram of the rotor iron core of an embedded permanent magnet motor. The structure of the rotor iron core 2 is a prior art, and it includes a magnetic isolation bridge 2.1, a shaft hole 2.2, a magnet slot 2.3, an outer circle of the iron core 2.4, etc.

[0039] As shown in the attached Figure 10 figure, when the present utility model is used, the rotor iron core 2 is installed in the tooling base 1. Each groove 1.3 is respectively aligned with the magnetic isolation bridge part at the corresponding position of the rotor iron core 2. Then, the end plate 3 is placed on the upper part of the rotor iron core 2, and the screw 4 passes through the circular hole 1.1 at the center of the bottom plate 1.4 and the shaft hole 2.2 of the rotor and is threadedly connected to the threaded hole at the center of the end plate 3, so that the rotor iron core 2 is fixed in the tooling base 1.

[0040] During nitriding treatment, the rotor core fixed by the tooling is placed in the nitriding furnace for nitriding. Since the magnetic isolation bridge part of the rotor core 2 is not protected by the tooth guards and end plates, it will be nitrided. After nitriding treatment, the magnetic resistance of the magnetic bridge increases, which can effectively reduce the magnetic leakage. The other parts of the rotor core are protected by the tooth guards, end plates, etc., and their magnetic permeability remains unchanged.

[0041] Other parts in this embodiment are all prior arts and will not be elaborated here.

[0042] Embodiment 2

[0043] As shown in the Figures 11 - 18 accompanying drawings, this embodiment is basically the same as Embodiment 1, and the difference lies in that: the end plate fixing structure adopted in this embodiment is different from that in Embodiment 1.

[0044] In this embodiment, a circular hole is not provided at the center of the bottom plate 1.4 of the tooling base 1, and a threaded hole is not provided at the center of the end plate 3 either.

[0045] In this embodiment, a plurality of end plate mounting protrusions 3.1 protruding outward are provided on the outer circumference of the end plate 3. The end plate mounting protrusions 3.1 correspond to the tooth guards 1.2 of the tooling base 1. An end plate mounting groove 1.5 is provided on the inner side of the tooth guard 1.2 of the tooling base 1 at the position where it cooperates with the end plate 3. The end plate 3 is connected in a matching manner through the end plate mounting protrusions 3.1 on it and the end plate mounting groove 1.5 on the inner side of the tooth guard 1.2 of the tooling base 1.

[0046] During use, the rotor core 2 is installed in the tooling base 1, and each groove 1.3 is respectively aligned with the magnetic isolation bridge part at the corresponding position of the rotor core 2. Then, the end plate 3 is placed on the upper part of the rotor core 2. The end plate mounting protrusions 3.1 of the end plate 3 can be inserted or screwed into the end plate mounting groove 1.5 on the inner side of the tooth guard 1.2, so as to fix the rotor core 2 in the tooling base 1.

[0047] Other parts in this embodiment are the same as those in Embodiment 1 and will not be elaborated here.

Claims

1. A nitriding tooling for the magnetic isolation bridge of a motor rotor, characterized in that: It includes a tooling base (1), an end plate (3), and an end plate fixing structure. The tooling base (1) is a cylindrical structure with an open upper part and a bottom plate. There is a receiving space for a coaxially arranged rotor core inside the cylindrical structure. A plurality of grooves (1.3) penetrating the height of the cylindrical wall are evenly formed on the cylindrical wall of the cylindrical structure. The grooves (1.3) divide the cylindrical wall of the cylindrical structure into a plurality of guard teeth (1.2). The number of the grooves (1.3) and the guard teeth (1.2) is the same as the number of rotor poles, and the grooves (1.3) correspond to the magnetic isolation bridge part of the rotor core. The end plate (3) is a disc that can be fitted with the inner diameter of the open end of the tooling base (1). The end plate (3) is connected to the open end of the tooling base (1) through the end plate fixing structure.

2. The nitriding tooling for the magnetic isolation bridge of the motor rotor according to claim 1, wherein: The inner diameter of the cylindrical structure is 0.02 mm - 0.05 mm larger than the outer diameter of the rotor core.

3. The nitriding tooling for the magnetic isolation bridge of the motor rotor according to claim 1, wherein: Six grooves (1.3) and six guard teeth (1.2) are provided on the tooling base (1).

4. The nitriding tooling for the magnetic isolation bridge of the motor rotor according to claim 1 or 2 or 3, characterized in that: A round hole is provided at the center of the bottom plate of the tooling base (1), and a threaded hole is provided at the center of the end plate (3). The tooling base (1) and the end plate (3) are connected through a screw (4) passing through their centers.

5. The nitriding tooling for the magnetic isolation bridge of the motor rotor according to claim 1 or 2 or 3, characterized in that: A plurality of outwardly protruding end plate mounting protrusions (3.1) are circumferentially arranged on the outer circumference of the end plate (3). The end plate mounting protrusions (3.1) correspond to the guard teeth (1.2) of the tooling base (1). An end plate mounting groove (1.5) is formed on the inner side of the guard teeth (1.2) of the tooling base (1) at the place where it cooperates with the end plate (3). The end plate (3) is connected to the end plate mounting groove (1.5) on the inner side of the guard teeth (1.2) of the tooling base (1) through its end plate mounting protrusions (3.1).

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