Gradient ring-shaped bonded magnet and manufacturing method thereof, motor

Abstract

To provide a gradient ring-shaped bonded magnet and a preparation method therefor, and a motor.SOLUTION: A gradient ring-shaped bonded magnet includes a magnet body 1 and at least one reinforcement layer 2. The magnet body is a ring-shaped cylinder, and the reinforcement layer is in pressing fit with a surface of the magnet body. A material of the magnet body is a first permanent magnet, and a material of the reinforcement layer is a second permanent magnet. The coercivity property, the remanence property and / or the maximum working temperature of the second permanent magnet are / is higher than those of the first permanent magnet. The gradient ring-shaped bonded magnet can achieve the local reinforcement of the ring-shaped bonded magnet, effectively improve the demagnetization resistance and the high-temperature resistance of the ring-shaped bonded magnet in a motor application, effectively save the use amount of precious metals such as dysprosium and terbium, and reduce the material cost of the permanent magnet. Furthermore, a preparation method for the gradient ring-shaped bonded magnet has the advantages of simple process, low processing cost, no need of additional equipment and suitability for mass production.SELECTED DRAWING: Figure 1a

Description

[Technical field]

[0001] The present invention relates to the field of magnet processing for motors, and more particularly to a gradient ring-shaped bonded magnet and its manufacturing method, and a motor. [Background technology]

[0002] At present, surface-mounted permanent magnet motors have the advantages of high efficiency, large power density, simple structure, etc., and are therefore widely used in various industries. Surface-mounted permanent magnet motors also have some drawbacks, such as the permanent magnets of surface-mounted permanent magnet motors directly facing the stator of the motor and reacting with the armature, which results in high temperatures and the risk of demagnetization. Elements such as dysprosium and terbium can effectively improve the coercive force of magnetic materials such as neodymium iron boron, but the cost of permanent magnet materials increases due to the high cost of elements such as dysprosium and terbium. Magnets such as sintered neodymium iron boron can achieve local strengthening of permanent magnetic materials by means such as area-selected grain boundary diffusion, which can effectively improve the coercive force of permanent magnets while allowing the use of less expensive metal elements such as dysprosium and terbium. Bonded magnets currently have no corresponding means for achieving local strengthening, and are prone to demagnetization on the surface close to the armature of the stator, causing demagnetization of the motor. The method provided by the present invention can effectively improve the local anti-demagnetization ability of a ring-shaped bonded magnet, and can save the amount of expensive metals such as dysprosium and terbium used. Summary of the Invention [Problem to be solved by the invention]

[0003] The objective of the embodiments of the present invention is to provide a gradient ring-shaped bonded magnet, its manufacturing method, and motor, in which a reinforcing layer is provided on the surface of the magnet body, which can effectively improve the local demagnetization resistance and high temperature resistance of the ring-shaped bonded magnet, and effectively reduce the amount of expensive metals such as dysprosium and terbium used. [Means for solving the problem]

[0004] In order to solve the above technical problem, a first aspect of an embodiment of the present invention provides a gradient ring-shaped bonded magnet, the gradient ring-shaped bonded magnet including a magnet body and at least one reinforcing layer; The magnet body is a ring-shaped cylindrical body, The reinforcing layer is pressure-bonded to the surface of the magnet body, The material of the magnet body is a first permanent magnet, the material of the reinforcing layer is a second permanent magnet, and the coercive force performance, residual magnetization performance and / or maximum operating temperature of the second permanent magnet are higher than those of the first permanent magnet.

[0005] Furthermore, the material of the first permanent magnet and the second permanent magnet includes neodymium iron boron, samarium iron nitrogen, and / or samarium cobalt.

[0006] Furthermore, the reinforcing layer is a ring-shaped cylindrical body, The inner wall of the magnet body is pressed against the radially outer wall of the reinforcing layer, or The outer wall of the magnet body is pressure-bonded to the inner wall in the radial direction of the reinforcing layer.

[0007] Furthermore, the reinforcing layer is a ring-shaped cylindrical body, and the inner diameter and the outer diameter thereof are the same as the inner diameter and the outer diameter of the magnet body, The reinforcing layer is one, and the axial side wall of the reinforcing layer is pressure-bonded to the axial end side wall of the magnet body, or The reinforcing layer is one, the magnet body includes a first body and a second body, both of which are ring-shaped cylindrical bodies, and the side walls of one end of each of the first body and the second body in the axial direction are press-bonded to the side walls of both ends of the reinforcing layer in the axial direction, respectively; or There are two reinforcing layers, and the side walls of the reinforcing layers in the axial direction are pressure-bonded to the side walls at both ends of the magnet body in the axial direction.

[0008] Further, a plurality of grooves are provided on the radial inner wall or the radial outer wall of the magnet body, The reinforcing layer includes an arc-shaped sheet-like reinforcing body that matches the shape of the groove, The reinforcing member is disposed within the groove, and is pressed against the bottom of the groove.

[0009] Correspondingly, a second aspect of an embodiment of the present invention provides a method for manufacturing the gradient ring-shaped bonded magnet, the method comprising the steps of: Step 1: Obtaining structural parameters and connection position parameters of a magnet body and a reinforcing layer based on a motor structure; Step 2: obtaining a preform for a magnet body and a preform for a reinforcing layer based on the structural parameters and the connection position parameters; In step 3, the preform of the magnet body and the preform of the reinforcing layer are fitted together, pressed, and cured.

[0010] Furthermore, the ratio between the magnet body and the reinforcing layer is the ratio between the normal safe area and the area susceptible to demagnetization under the worst operating conditions of the motor.

[0011] Furthermore, in step 2, the density of the preform of the magnet body and the preform of the reinforcing layer is 3 to 4 g / cm 3 and In step 3, the density of the gradient ring-shaped bonded magnet pressed by the final press die is 6.0 to 6.3 g / cm 3 It is.

[0012] Furthermore, in step 3, the curing temperature is 120°C to 180°C, and preferably, the curing temperature is 150°C; The curing time is from 1 hour to 3 hours, and preferably the curing time is 2 hours.

[0013] Correspondingly, a third aspect of an embodiment of the present invention provides a motor including the above gradient ring bonded magnet. Effect of the Invention

[0014] The above technical solutions of the embodiments of the present invention have the following beneficial technical effects: The above-mentioned gradient ring-shaped bonded magnet can realize local strengthening of the ring-shaped bonded magnet, effectively improving the demagnetization resistance and high temperature resistance of the ring-shaped bonded magnet when applied to motors, effectively saving the usage of expensive metals such as dysprosium, terbium, etc., and reducing the material costs of permanent magnets. In addition, the manufacturing method of the gradient ring-shaped bonded magnet provided by the present invention has a simple process, low processing costs, does not require additional equipment, etc., and can be applied to mass production. [Brief description of the drawings]

[0015] [Figure 1a] FIG. 2 is a schematic diagram of a gradient ring-shaped bonded magnet according to a first embodiment of the present invention; [Figure 1b] FIG. 2 is a schematic diagram of a gradient ring-shaped bonded magnet according to a second embodiment of the present invention; [Figure 1c] FIG. 13 is a schematic diagram of a gradient ring-shaped bonded magnet according to a third embodiment of the present invention; [Figure 1d] FIG. 13 is a schematic diagram of a gradient ring-shaped bonded magnet according to a fourth embodiment of the present invention. [Figure 1e] FIG. 5 is a schematic diagram of Example 5 of a gradient ring-shaped bonded magnet provided by an embodiment of the present invention. [Figure 1f] FIG. 13 is a schematic diagram of a sixth embodiment of a gradient ring-shaped bonded magnet provided by an embodiment of the present invention. [Figure 1g] FIG. 13 is a schematic diagram of a seventh embodiment of a gradient ring-shaped bonded magnet provided by an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram of a method for manufacturing a gradient ring-shaped bonded magnet according to an embodiment of the present invention; [Diagram 3] FIG. 2 is an example of a two-dimensional topology diagram of a 6-slot, 4-pole surface-mounted permanent magnet motor provided by an embodiment of the present invention. [Figure 4]FIG. 1 is a schematic diagram of an example of the surface demagnetization factor of a rotor of a 6-slot, 4-pole, surface-mounted permanent magnet motor provided by an embodiment of the present invention, to which no gradient ring-shaped bonded magnet is attached. [Diagram 5] FIG. 1 is a schematic diagram of an example of the surface demagnetization factor of a rotor of a 6-slot, 4-pole, surface-mounted permanent magnet motor equipped with gradient ring-shaped bonded magnets provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in more detail below with reference to specific embodiments and drawings. These descriptions are merely illustrative and do not limit the scope of the present invention. In the following description, descriptions of known configurations and technologies are omitted to avoid unnecessary confusion of the concept of the present invention.

[0017] Referring to FIG. 1, in order to solve the above technical problems, a first aspect of an embodiment of the present invention provides a gradient ring-shaped bonded magnet, which includes a magnet body 1 and at least one reinforcing layer 2, the magnet body 1 is a ring-shaped cylindrical body, the reinforcing layer 2 is pressed onto the surface of the magnet body 1, the material of the magnet body 1 is a first permanent magnet, the material of the reinforcing layer 2 is a second permanent magnet, and the coercive force performance, residual magnetization performance and / or maximum operating temperature of the first permanent magnet are higher than those of the second permanent magnet.

[0018] Specifically, the material of the first permanent magnet and the second permanent magnet includes neodymium iron boron, samarium iron nitrogen, and / or samarium cobalt.

[0019] The base material of the second permanent magnet may be the same as or different from the base material of the first permanent magnet, provided that the second permanent magnet has higher coercivity performance, residual magnetization performance and / or maximum operating temperature than the first permanent magnet, regardless of whether the base materials are the same or different.

[0020] The structure of the gradient ring bonded magnet will be described below in several examples. 1a, in Example 1 of the gradient ring-shaped bonded magnet, the reinforcing layer 2 of the gradient ring-shaped bonded magnet is a ring-shaped cylinder, and the inner wall of the magnet body 1 is pressure-bonded to the outer wall in the radial direction of the reinforcing layer 2. That is, the ring-shaped cylinder reinforcing layer 2 is fitted onto the outside of the ring-shaped cylinder magnet body, and the two are fixed together by pressure bonding.

[0021] 1b, in Example 2 of the gradient ring-shaped bonded magnet, the reinforcing layer 2 of the gradient ring-shaped bonded magnet is a ring-shaped cylinder, and the outer wall of the magnet body 1 is pressure-bonded to the radially inner wall of the reinforcing layer 2. That is, the ring-shaped cylindrical magnet body is fitted onto the outside of the ring-shaped cylindrical reinforcing layer 2, and the two are fixed together by pressure bonding.

[0022] 1c, in Example 3 of the gradient ring-shaped bonded magnet, the reinforcing layer 2 of the gradient ring-shaped bonded magnet is a ring-shaped cylinder whose inner and outer diameters are the same as those of the magnet body 1, but whose axial lengths are different. There is one reinforcing layer 2, which is provided at one axial end of the magnet body 1, and the axial sidewall of the reinforcing layer 2 is pressure-bonded to the sidewall of one axial end of the magnet body.

[0023] 1d, in Example 4 of the gradient ring-shaped bonded magnet, the reinforcing layer 2 of the gradient ring-shaped bonded magnet is a ring-shaped cylinder whose inner and outer diameters are the same as those of the magnet body 1, but whose axial lengths are different. There are two reinforcing layers 2, which are provided at both ends of the magnet body 1 in the axial direction, and the side walls of the reinforcing layers 2 in the axial direction are pressure-bonded to the side walls of both ends of the magnet body in the axial direction.

[0024] 1e, in Example 5 of the gradient ring-shaped bonded magnet, the reinforcing layer 2 of the gradient ring-shaped bonded magnet is a ring-shaped cylinder whose inner and outer diameters are the same as those of the magnet body 1, but the lengths of the two in the axial direction are different. The reinforcing layer 2 is one, and the magnet body 1 is two identical parts, each located at both ends of the reinforcing layer 2 in the axial direction, and the side walls in the axial direction of the two magnet bodies 1 are respectively pressed against the side walls at both ends of the reinforcing layer 2 in the axial direction.

[0025] Referring to Figure 1f, in Example 6 of the gradient ring-shaped bonded magnet, a plurality of grooves are provided on the radial inner wall of the magnet body 1, and the reinforcing layer 2 includes a plurality of arc-shaped sheet-like reinforcing bodies that match the shape of the grooves, the reinforcing bodies are provided in the grooves, and the reinforcing bodies are pressed against the bottom of the grooves of the magnet body 1.

[0026] Referring to Figure 1g, in Example 7 of the gradient ring-shaped bonded magnet, a plurality of grooves are provided in the radial outer wall of the magnet body 1, and the reinforcing layer 2 includes a plurality of arc-shaped sheet-like reinforcing bodies that match the shape of the grooves, and the reinforcing bodies are provided in the grooves and pressed against the bottom of the grooves of the magnet body 1.

[0027] Different materials or different model numbers of materials are used for the magnet body 1 and the reinforcing layer 2, and the specific position of the reinforcing layer 2 is determined according to the specific motor structure and application needs, and the specific dimensions of the magnet body 1 and the reinforcing layer 2 are determined through calculations, and corresponding preforms are manufactured. Finally, the two preforms are fitted together, and then pressed and hardened to obtain the entire ring-shaped magnet structure.

[0028] The above-mentioned gradient ring-shaped bonded magnet is based on the fact that the portion of the permanent magnet close to the stator armature or the edge portion of the magnet in a surface-mounted permanent magnet motor is very susceptible to demagnetization, and attempts to locally strengthen one side or edge region of the ring-shaped bonded magnet close to the stator armature. In accordance with the processing process of the ring-shaped bonded magnet, a pre-compression ring of a reinforcing layer and a pre-compression ring of a normal layer are added, and multiple pre-compression rings are fitted together and attached for final pressing and hardening, thereby achieving the purpose of locally strengthening the ring-shaped bonded magnet.

[0029] Correspondingly, a second aspect of an embodiment of the present invention provides a method for manufacturing the gradient ring-shaped bonded magnet, the method comprising the steps of: Step 1: Obtaining structural parameters and connection position parameters of the magnet body 1 and the reinforcing layer 2 based on the structure of the motor; Step 2: Obtaining a magnet body 1 preform and a reinforcing layer 2 preform based on the structural parameters and the connection position parameters; In step 3, the magnet body 1 preform and the reinforcing layer 2 preform are fitted together, pressed, and hardened to obtain a gradient ring-shaped bonded magnet.

[0030] Furthermore, the ratio between the magnet body and the reinforcing layer is the ratio between the normal safe area and the area susceptible to demagnetization under the worst operating conditions of the motor.

[0031] Furthermore, in step 2, the density of the preform of the magnet body and the preform of the reinforcing layer is 3 to 4 g / cm 3 and In step 3, the density of the gradient ring-shaped bonded magnet pressed by the final pressing die is 6.0-6.3g / cm 3 It is.

[0032] Furthermore, in step 3, the curing temperature is 120° C. to 180° C., preferably the curing temperature is 150° C., and the curing time is 1 hour to 3 hours, preferably the curing time is 2 hours.

[0033] The above manufacturing method will now be described in detail with reference to several examples. Example 1 Using a bonded magnet ring permanent magnet motor with an inner diameter of 18 mm, an outer diameter of 26 mm, and a height of 20 mm, calculations were performed to determine that demagnetization would occur on the surface layer of the motor under the worst operating conditions, with the distribution depth being approximately 1.5 mm. Calculations were also performed to determine that the reinforcing layer was the surface layer of the bonded magnet ring, with a thickness of 1.5 mm, and that the magnet body was 2.5 mm thick. Further simulation calculations were performed to determine magnetic performance such that demagnetization would not occur on the surface layer of the magnet under the worst operating conditions of a permanent magnet motor using a bonded magnet ring, and the magnetic powder of the applicable model number was selected and pressed.

[0034] First, the inner diameter is 23 mm, the outer diameter is 26 mm, the height is 40 mm, and the density is 3.0 g / cm 3 The preload ring of the reinforcing layer has an inner diameter of 18 mm, an outer diameter of 23 mm, a height of 40 mm, and a density of 3.0 g / cm 3 The main layer of the magnet ring is pre-pressed, and then the reinforcing layer is assembled with the main layer. After the assembly is completed, it is put into the final press to obtain a final shape with an inner diameter of 18 mm, an outer diameter of 26 mm, a height of 20 mm, and a density of 6.0 g / cm. 3 The bonded magnet ring body is then placed in a 150° C. oven and heated for 2 hours to complete the final cure.

[0035] Example 2 Using a bonded magnet ring permanent magnet motor with an inner diameter of 22 mm, an outer diameter of 30 mm, and a height of 15 mm, calculations were performed to determine that demagnetization would occur on the surface layer of the motor under the worst operating conditions, with the distribution depth being approximately 1.8 mm. Calculations were also performed to determine that the reinforcing layer was the surface layer of the bonded magnet ring, with a thickness of 1.8 mm, and that the magnet body was 2.2 mm thick. Furthermore, simulation calculations were performed to obtain the magnet performance when no demagnetization would occur on the magnet surface layer under the worst operating conditions of a permanent magnet motor using a bonded magnet ring, and the magnetic powder of that model number was selected and pressed.

[0036] First, the inner diameter is 22 mm, the outer diameter is 25.6 mm, the height is 30 mm, and the density is 4.0 g / cm 3 The preload ring of the reinforcing layer has an inner diameter of 25.6 mm, an outer diameter of 30 mm, a height of 30 mm, and a density of 4.0 g / cm 3 The main layer of the magnet ring is pre-pressed, and then the reinforcing layer is assembled with the main layer. After the assembly is completed, it is put into a final press to produce a ring with an inner diameter of 22 mm, an outer diameter of 30 mm, a height of 15 mm, and a density of 6.2 g / cm. 3 The bonded magnet ring body is then placed in a 120° C. oven and heated for 3 hours to complete the final cure.

[0037] Example 3 Using a bonded magnet ring permanent magnet motor with an inner diameter of 16 mm, an outer diameter of 22 mm, and a height of 15 mm, calculations were performed to determine that demagnetization would occur on the surface layer of the motor under the worst operating conditions, with the distribution depth being approximately 1 mm. Calculations were also performed to determine that the reinforcing layer was the surface layer of the bonded magnet ring, with a thickness of 1 mm, and that the magnet body was 2 mm thick. Furthermore, simulation calculations were performed to obtain the magnet performance when no demagnetization would occur on the magnet surface layer under the worst operating conditions of a permanent magnet motor using a bonded magnet ring, and the magnetic powder of that model number was selected and pressed.

[0038] First, the inner diameter is 16 mm, the outer diameter is 18 mm, the height is 30 mm, and the density is 3.5 g / cm 3 The reinforcement layer preload ring has an inner diameter of 18 mm, an outer diameter of 22 mm, a height of 30 mm, and a density of 3.5 g / cm 3 The main layer of the magnet ring is pre-pressed, and then the reinforcing layer is assembled with the main layer. After the assembly is completed, it is put into a final press to produce a ring with an inner diameter of 16 mm, an outer diameter of 22 mm, a height of 15 mm, and a density of 6.3 g / cm. 3 The bonded magnet ring body is then placed in a 180° C. oven and heated for 1 hour to complete the final cure.

[0039] Correspondingly, a third aspect of an embodiment of the present invention provides a motor including the above gradient ring bonded magnet.

[0040] Referring to Figures 3, 4 and 5, in one specific embodiment, Figure 3 is a two-dimensional topology diagram of a 6-slot, 4-pole surface-mounted permanent magnet motor, which, from the inside to the outside in the radial direction, are the motor shaft 6, the motor rotor core 3, the reinforcing layer 2, the magnet body 1, the motor stator core 4 and the motor stator winding 5.

[0041] In the above embodiment, a 4-pole ring-shaped bonded permanent magnet with an outer diameter of 26 mm and an inner diameter of 18 mm is used, and the ring-shaped permanent magnet is applied to a 6-slot 4-pole surface-mounted permanent magnet motor, and the motor structure is shown in Figure 3. First, the thickness of the surface layer where the demagnetization rate of the rotor structure of the normal ring-shaped permanent magnet of the motor is greater than 5% under the worst operating condition is calculated, and as shown in Figure 4, the area where the demagnetization rate is greater than 5% has a thickness of 1.5 mm. Then, based on the calculated thickness, a magnetic powder with high coercivity is selected and mixed, and a pre-loaded reinforcing layer magnet with an outer diameter of 26 mm and an inner diameter of 23 mm is pressed, and the original normal magnetic powder is used to mix the powder and press a normal layer magnet with an outer diameter of 23 mm and an inner diameter of 18 mm. After the two pre-loaded rings are completed, they are assembled together, and then put into a final mold for final pressing to obtain a gradient ring-shaped bonded magnet with an outer diameter of 26 mm and an inner diameter of 18 mm, and the bonded magnet is hardened. After the hardening was completed, the gradient ring-shaped bonded magnet was attached to the target motor and a test was conducted. The test results, as shown in Figure 5, showed that under the same operating conditions, the surface-mounted permanent magnet motor using the gradient ring-shaped bonded magnet had an area where the demagnetization rate was greater than 5% that was almost zero.

[0042] An embodiment of the present invention provides a gradient ring-shaped bonded magnet and its manufacturing method, which provides protection for motors, and the gradient ring-shaped bonded magnet includes a magnet body and at least one reinforcing layer, the magnet body is a ring-shaped cylindrical body, the reinforcing layer is pressed onto the surface of the magnet body, the material of the magnet body is a first permanent magnet, the material of the reinforcing layer is a second permanent magnet, and the coercive force performance, residual magnetization performance and / or maximum operating temperature of the second permanent magnet are higher than those of the first permanent magnet. The above technical solution has the following effects: The above-mentioned gradient ring-shaped bonded magnet can realize local strengthening of the ring-shaped bonded magnet, effectively improving the demagnetization resistance and high temperature resistance of the ring-shaped bonded magnet when applied to motors, effectively saving the usage of expensive metals such as dysprosium, terbium, etc., reducing the material costs of permanent magnets, and the manufacturing method of the gradient ring-shaped bonded magnet provided by the present invention has a simple process, low processing costs, does not require additional equipment, etc., and can be applied to mass production.

[0043] It should be understood that the above specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention, and are not intended to limit the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the scope of protection of the present invention. Furthermore, it is intended to include all modifications within the meaning and scope of the claims as indicated by the claims. [Explanation of symbols]

[0044] 1 Magnet body 2 Reinforcement layer 3. Motor rotor core 4. Motor stator core 5 Motor stator windings 6 Motor shaft

Claims

1. A gradient ring bonded magnet, The magnet comprises a magnet body (1) and at least one reinforcing layer (2), The magnet body (1) is a ring-shaped cylindrical body, The reinforcing layer (2) is pressure-bonded to the surface of the magnet body (1), A plurality of grooves are provided on the radial inner wall or the radial outer wall of the magnet body (1), The reinforcing layer (2) includes a plurality of arc-shaped sheet-like reinforcing bodies that match the shape of the groove, The reinforcing body is provided in the groove, and the reinforcing body is pressed against a bottom portion of the groove, A gradient ring bonded magnet, characterized in that the material of the magnet body (1) is a first permanent magnet, the material of the reinforcing layer (2) is a second permanent magnet, and the coercive force performance, residual magnetization performance and / or maximum operating temperature of the second permanent magnet are higher than those of the first permanent magnet.

2. 2. The gradient ring bonded magnet of claim 1, wherein the material of the first permanent magnet and the second permanent magnet comprises neodymium iron boron, samarium iron nitrogen, and / or samarium cobalt.

3. The reinforcing layer (2) is a ring-shaped cylindrical body, The inner wall of the magnet body (1) is pressed against the outer wall of the reinforcing layer (2) in the radial direction, or 2. The gradient ring bonded magnet according to claim 1, characterized in that the outer wall of the magnet body (1) is pressed against the inner wall in the radial direction of the reinforcing layer (2).

4. The reinforcing layer (2) is a ring-shaped cylindrical body, the inner diameter and the outer diameter of which are the same as the inner diameter and the outer diameter of the magnet body (1), There is one reinforcing layer (2), and the side wall of the reinforcing layer (2) in the axial direction is pressure-bonded to the side wall of one end of the magnet body (1) in the axial direction, or There is one reinforcing layer (2), the magnet body (1) includes a first body and a second body, both of which are ring-shaped cylindrical bodies, and the side walls of one end of each of the first body and the second body in the axial direction are press-bonded to the side walls of both ends of the reinforcing layer (2) in the axial direction, respectively; or The gradient ring-shaped bonded magnet according to claim 1, characterized in that there are two reinforcing layers (2), and the axial side walls of the reinforcing layers (2) are pressed against the side walls at both axial ends of the magnet body (1).

5. A method for manufacturing a gradient ring-shaped bonded magnet according to any one of claims 1 to 4, comprising the steps of: Step 1: Obtaining structural parameters and connection position parameters of a magnet body and a reinforcing layer based on a motor structure; Step 2: Obtaining a magnet body and a reinforcing layer based on the structural parameters and the connection position parameters; Step 3: The manufacturing method of the gradient ring-shaped bonded magnet includes fitting the magnet body and the reinforcing layer, pressing, and hardening the magnet to obtain a gradient ring-shaped bonded magnet.

6. In step 2, the density of the magnet body and the reinforcing layer is 3 to 4 g / cm ３ and In step 3, the density of the gradient ring-shaped bonded magnet pressed by the final press die is 6.0 to 6.3 g / cm ３ 6. The method for producing a gradient ring shaped bonded magnet according to claim 5, wherein:

7. In step 3, the temperature of the curing is 120°C to 180°C, preferably, the temperature of the curing is 150°C; The method for manufacturing the gradient ring-shaped bonded magnet as claimed in claim 5, wherein the curing time is 1 hour to 3 hours, and preferably the curing time is 2 hours.

8. A motor, A motor comprising the gradient ring-shaped bonded magnet according to any one of claims 1 to 4.

Images