Stable and reliable food processor

Abstract

The invention relates to a stable and reliable food processor which comprises a permanent magnet direct current brushless motor, the motor comprises a stator and a rotor, the rotor comprises a rotor iron core and a permanent magnet, the inner side of the outer edge of the rotor iron core is provided with an installation groove for the permanent magnet to be inserted, and the position, opposite to the permanent magnet, of the outer edge of the rotor iron core is provided with a rotor salient pole protruding outwards. A groove is formed between every two adjacent rotor salient poles, the rotor further comprises a fixing cage which is arranged outside the rotor iron core and integrally formed, the fixing cage comprises end plates located at the two ends of the rotor iron core and fixing columns located on the outer side wall of the rotor iron core and connected with the end plates at the two ends, the fixing columns are located at the grooves, and the outer diameter of the fixing columns is not larger than that of the rotor salient poles. The fixing cage is provided with the fixing columns at the grooves to integrally wrap the rotor, the strength of the fixing cage is increased, the rotor iron core and the permanent magnets are fixed and limited, and the situation that the strength of the fixing cage is affected due to the fact that the periphery bears large centrifugal force when the fixing cage is fixedly connected only through the connecting column in the center and deforms is avoided.

Description

Technical Field

[0001] The invention relates to the field of food processing, and in particular to a food processing machine which uses a permanent magnet direct current brushless motor to realize power drive. Background Art

[0002] Traditional food processors mostly use series-excited motors to achieve power drive, but the speed difference of series-excited motors is large when they are working, the no-load noise is large, and they can only rotate in one direction, which greatly reduces the user experience of existing food processors. As an improvement, existing food processors use permanent magnet brushless DC motors to replace traditional series-excited motors. Compared with series-excited motors, permanent magnet brushless DC motors have no carbon brush noise when rotating, high motor power density, long service life, and are thin and light, stable in operation, and gradually become the first choice for food processors.

[0003] Although permanent magnet brushless DC motor is a common technology in the field of motors, when it is applied in the field of food processing machines, it is limited by the working conditions of the food processing machines, the size and volume of the products, the speed, power, noise and control requirements of the food processing machines, which makes the permanent magnet brushless DC motor undergo more changes when it is transformed and applied in the field of food processing machines. The general technical solution is that the motor includes a stator and a rotor, the rotor includes a rotor core and a permanent magnet, the permanent magnet is embedded in the rotor core, a fixing plate is arranged at both ends of the rotor core, and a fixing member passing through the rotor core in the axial direction is arranged to fix the fixing plate, the rotor core and the permanent magnet. For example, CN202211422868.1 discloses a motor for a food processor, the rotor includes a front plastic baffle, a rear plastic baffle, a rotor core, and a plurality of magnets, and the front plastic baffle and the rear plastic baffle are respectively installed at the front end and the rear end of the rotor core. However, in such a technical solution, the various components of the motor are assembled together, and there are assembly errors during the assembly process, which reduces the stability of the motor. After working for a long time, the various parts are affected by vibration and impact, and the errors are further enlarged, which further reduces the working stability of the motor and affects the service life and user experience of the food processor.

[0004] As an improvement, CN202120856590.3 discloses a motor for a food processor, in which the rotor assembly is an embedded permanent magnet, including a rotor core, a permanent magnet plugged into the rotor core, and a plastic frame. The plastic frame is an injection molded part, which is integrally coated on the rotor core and the permanent magnet. In this way, the plastic frame is integrally injection molded to completely wrap the permanent magnet and the rotor core, which can partially solve the technical problem of unstable operation of each component in the aforementioned solution. However, in such a technical solution, the overall strength of the rotor assembly is not better improved. In particular, it should be noted that such a setting method cannot effectively improve the air gap distance between the rotor and the stator, and thus cannot better improve the operating performance of the motor itself. Such technical problems are also not involved in the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a stable and reliable food processing machine, which can simultaneously optimize the matching air gap between the rotor and the stator, improve the magnetic field distribution of the rotor itself and the magnetic field distribution between the rotor and the stator, and thus make the rotor of the motor reach the optimal combination scheme while fully improving the stability of the motor rotor.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a stable and reliable food processing machine, comprising a permanent magnet DC brushless motor and a processing component driven by the motor, the motor comprising a stator and a rotor, the rotor comprising a rotor core and a permanent magnet, characterized in that an installation groove for inserting the permanent magnet is provided on the inner side of the outer edge of the rotor core, the installation groove is an even number and is arranged in sequence along the circumference of the rotor core, an outwardly protruding rotor salient pole is provided at a position relative to the outer edge of the rotor core and the permanent magnet, and a groove is formed between adjacent rotor salient poles, the rotor also includes a fixed cage arranged outside the rotor core and integrally formed, the fixed cage includes end plates located at both ends of the rotor core and fixed columns located on the outer side wall of the rotor core and connecting the end plates at both ends, the fixed column is located at the groove and the outer diameter of the fixed column is not greater than the outer diameter of the rotor salient pole.

[0007] Preferably, the outer edge of the end plate is further provided with a stabilizing rib, the stabilizing rib is annular and extends toward the outside of the end plate along the axial direction of the rotor, and the fixing column connects the stabilizing ribs at both ends.

[0008] Preferably, the stabilizing rib is provided with a stabilizing hole on the peripheral side wall or the top wall.

[0009] Preferably, the rotor core is provided with a connecting hole located inside the mounting groove and penetrating in the axial direction, and the fixing cage includes a connecting column located in the connecting hole and connecting the end plates at both ends.

[0010] Preferably, the inner side wall of the installation groove is provided with a positioning groove, and the fixing cage includes a positioning column located in the positioning groove and connecting the end plates at both ends, and the positioning column is in contact with the permanent magnet.

[0011] Preferably, the angle formed by a single fixing column in the circumferential direction is α, the angle formed by a single rotor protrusion in the circumferential direction is β, and 1 / 4≤α / β≤1 / 2.

[0012] Preferably, the outer diameter of the fixing column is d, the outer diameter of the rotor salient pole is D, and Dd≥1 mm.

[0013] Preferably, cavities are provided at both ends of the mounting grooves, and the rotor is located between the cavities of two adjacent mounting grooves to form a magnetic isolation bridge, and the angle between the extended part of the magnetic isolation bridge and the extended line of the rotor radius is θ, 30°≤θ≤80°.

[0014] Preferably, the rotor core includes a core body and a rotor salient pole, the rotor salient pole is fixed to the outside of the permanent magnet through the fixing column, cavities are provided at both ends of the mounting slot, the fixing column passes through the cavity and connects the cavities of two adjacent mounting slots to form a magnetic isolation bridge between the two permanent magnets.

[0015] Preferably, the rotor further comprises a fan integrally formed with the fixed cage, the fan extending radially outward along an end plate located at the end of the motor, and the fan comprises a fan body and fan blades.

[0016] After adopting the above scheme, the present invention has the following advantages:

[0017] 1. The present application arranges the permanent magnets at the outer edge of the rotor core and arranges them in sequence along the circumferential direction. The N poles and S poles of adjacent permanent magnets are arranged in a leading manner, so that a back-electromotive force waveform with better sinusoidal degree can be obtained, making the rotor smoother when switching magnetic poles, avoiding the jitter caused by too short a magnetic pole switching stroke when the permanent magnets are arranged radially, thereby ensuring that the operation of the food processor is more stable and reliable, and can also reduce the noise of the product. A rotor salient pole opposite to the permanent magnet is arranged at the outer edge of the rotor core, and a groove is formed between adjacent rotor salient poles. The groove is used to form a magnetic isolation bridge between adjacent permanent magnets, thereby minimizing the magnetic flux between adjacent permanent magnets in the rotor, fully ensuring that the magnetic lines of force of the permanent magnets can pass through the stator, thereby improving the working efficiency of the motor. At the same time, the rotor salient pole can also improve the fixing strength of the rotor to the permanent magnet, and reduce the air gap between the rotor and the stator through the permanent magnet. In this way, the air gap between the stator and the rotor core is unevenly distributed. From the top of the rotor salient pole of the rotor core to the bottom of the groove, the air gap gradually increases, is the largest at the bottom of the groove, and then gradually decreases, so that the air gap presents a sinusoidal distribution, the back electromotive force curve is smooth, the ripple torque of the motor operation is reduced, the stability of the motor operation is improved, and the noise and vibration are reduced.

[0018] The integrated fixed cage can fully wrap and position the rotor, improve the reliability of the fit between the permanent magnet and the rotor core, and avoid displacement of the permanent magnet and the rotor core under impact during long-term operation, ensuring stable and reliable performance of the electronics over a long life cycle. Since the permanent magnet and the mounting slot of the rotor core are fixed by an integrated fixed cage, there is no need to set glue between the permanent magnet and the mounting slot to fix the permanent magnet, and the effect of glue leakage on the motor rotor and stator is avoided.

[0019] The fixed cage is provided with a fixed column at the groove to wrap the rotor as a whole, increase the strength of the fixed cage itself, so that the fixed cage can better fix and limit the rotor core and the permanent magnet, and avoid the fixed cage in the prior art being fixedly connected only by the central connecting column, and the peripheral edge is subjected to large centrifugal force to produce deformation and affect the strength of the fixed cage. The end plates at both ends are used to cover the permanent magnet and form a cylindrical shape with a side wall opening with the fixed column, so that the fixed cage completely wraps the rotor core and forms a rotating body, and the rotor can maintain better dynamic balance during high-speed rotation. Furthermore, the outer diameter of the fixed column is not greater than the outer diameter of the rotor salient pole, so that the rotor salient pole extends from the opening, and the air gap between the rotor salient pole and the stator is ensured to be small enough. In this way, the rotor salient pole, the groove and the fixed column cooperate with each other to increase the strength between the rotor, and at the same time, by changing the air gap between the permanent magnet and the stator, the brushless motor works stably and reliably, and a stable balance is achieved between the three, so that the brushless motor is in the best working state. Preferably, the number of the fixing columns is greater than one, for example, the number of the fixing columns is the same as the number of the grooves, or the number of the fixing columns is a multiple of the number of the grooves, and the fixing columns are arranged to be rotationally symmetrical. Such an arrangement makes the fixing columns more balanced when the rotor is working. At the same time, the symmetrically arranged fixing columns also make the air gap present a symmetrical quasi-sinusoidal distribution.

[0020] 2. Stabilizing ribs are set on the outer edge of the end plate. The stabilizing ribs are annular and extend to the outside of the end plate along the axial direction of the rotor. The fixing columns connect the stabilizing ribs at both ends. The stabilizing ribs are used to increase the rotational inertia of the fixed cage, so that the rotor is stable and reliable during operation. The stabilizing ribs are set on the outer edge of the end plate, which increases the rotational radius of the stabilizing ribs. Under the premise of a fixed rotor diameter, the rotational inertia reaches the maximum state, making it easy to maintain the stability of the rotor. At the same time, the stabilizing ribs are used to connect the fixing columns, which strengthens the connection strength between the various components of the fixed cage, avoids the fixing columns and the end plates from being broken due to centrifugal force during high-speed operation, and ensures the reliability of the motor.

[0021] 3. Stabilizing holes are set on the side walls or top walls of the stabilizing ribs to adjust the dynamic balance of the rotor. Since the stabilizing ribs are located at the maximum radius of the rotor, a smaller number of stabilizing holes can be set to adjust a larger amount of moment of inertia, thereby making the rotor more dynamically balanced. At the same time, since the integral fixed cage is usually made of non-magnetic plastic, stabilizing holes are set on its structure, which will not affect the distribution of the magnetic lines of force of the rotor, ensuring that the magnetic air gap between the rotor and the stator is stable and reliable.

[0022] 4. Further, a connection hole is provided in the rotor core, and a connection column is provided in the fixed cage accordingly, so as to strengthen the strength of the fixed cage itself and enable the fixed cage to play a better fixing and limiting role on the rotor core.

[0023] 5. Further, a positioning groove is set on the side wall of the installation groove. When the fixed cage is integrally formed with the rotor core and the permanent magnet, the fluid passes through the positioning groove to fully contact and fuse with the permanent magnet and the rotor core, thereby strengthening the fixed limiting effect on the permanent magnet. At the same time, the positioning groove can be used to fit and fix the permanent magnet, so that the permanent magnet and the rotor are in the best magnetic matching state with the stator.

[0024] 6. The fixing column fills the groove formed between the salient poles of the rotor so that the outer diameter of the assembly formed by the fixing cage and the rotor core is close to that of a cylinder, so that the gap between the rotor and the stator is stable. Since the food processing machine described in the present application is usually used in high-speed operation (the speed is above 10,000 rpm), if the wrapping angle (that is, the angle formed by the fixing column in the circumferential direction) is set too large, the rotor air gap will be reduced, it will be difficult to process and the working state will be unstable. The fixing column is also prone to friction with the stator under the action of high-speed centrifugation. If the setting is too small, it will not be able to effectively play a fixing role, and the air gap between the groove and the stator will be too large, which is easy to generate noise.

[0025] 7. Similarly, under the premise of ensuring the stability and reliability of the fixed column and the fixed cage structure, the outer diameter difference between the fixed column and the rotor salient pole can be minimized to make the rotor assembly shape close to a cylinder, but this will inevitably increase the difficulty of producing the fixed cage and the rotor core, and the life of the motor cannot be guaranteed, or the cost of the motor will be greatly increased. Setting the outer diameter difference between the rotor salient pole and the fixed column to not less than 1mm can fully ensure the stable operation of the rotor and the stable and reliable magnetic air gap, making the rotor easy to manufacture.

[0026] 8. Since the rotor core is provided with a mounting groove and a rotor salient pole is formed outside the mounting groove, the rotor salient pole is subjected to a large centrifugal force when working at high-speed rotation, and the rotor salient pole is connected to the rotor core body through a magnetic isolation bridge. On the one hand, the magnetic isolation bridge will allow magnetic transmission between two adjacent permanent magnets through the rotor core. Therefore, it is necessary to compress the size of the magnetic isolation bridge as much as possible to reduce the magnetic energy of the two adjacent permanent magnets connected through the magnetic isolation bridge; but on the other hand, too small a size will make the strength of the magnetic isolation bridge unable to withstand the centrifugal force of the rotor salient pole, causing the rotor salient pole to break or deform at the magnetic isolation bridge, thereby affecting the normal use of the motor. The magnetic isolation bridge is set at an angle θ, so that the lateral force generated by the rotor salient pole on the magnetic isolation bridge is converted into an axial force on the magnetic isolation bridge, so as to reduce the influence of centrifugal force on the magnetic isolation bridge, and achieve the purpose of further reducing the size of the magnetic isolation bridge.

[0027] 9. The rotor salient poles are separated from the core body, so that adjacent permanent magnets no longer need to transmit magnetic force through the core, so that the magnetic force between permanent magnets can be transmitted through the stator to the maximum extent, thereby improving the working efficiency of the motor. Cavities are set at both ends of the installation slot, and fixed columns are used to fill the cavities and fix the rotor salient poles to ensure the normal operation of the rotor salient poles and the stability and reliability of the rotor.

[0028] 10. The fan and the fixed cage are formed in one piece, and the fan is used to generate cooling airflow for the motor, so that the rotor and stator can be cooled quickly. The integrated setting ensures the strength of the fan, avoids the error caused by the assembly between the fan and the rotor, and improves the stability and reliability of the rotor itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the overall structure of a first embodiment of a stable and reliable food processing machine according to the present invention.

[0030] Figure 2 This is a schematic diagram of the motor decomposition of the first embodiment of a stable and reliable food processing machine described in the present invention.

[0031] Figure 3 It is a schematic cross-sectional view of a motor of a first embodiment of a stable and reliable food processing machine according to the present invention.

[0032] Figure 4 This is a schematic diagram of the rotor disassembly of a first embodiment of a stable and reliable food processing machine according to the present invention.

[0033] Figure 5 This is a schematic diagram of the rotor structure of a first embodiment of a stable and reliable food processing machine according to the present invention.

[0034] Figure 6 It is a schematic diagram of the axial cross-section of the rotor of the first embodiment of a stable and reliable food processing machine described in the present invention.

[0035] Figure 7 This is a schematic diagram of the rotor structure of a first embodiment of a stable and reliable food processing machine according to the present invention.

[0036] Figure 8 It is a schematic diagram of a radial cross-section of a rotor of a first embodiment of a stable and reliable food processing machine according to the present invention.

[0037] Fig. 9 for Figure 8 A is a partial enlarged schematic diagram of the middle part.

[0038] Fig.10 This is a schematic diagram of the rotor structure of a second embodiment of a stable and reliable food processing machine according to the present invention.

[0039] Fig.11 It is a partial schematic diagram of the rotor structure of the third embodiment of a stable and reliable food processing machine described in the present invention.

[0040] Fig.12 This is a schematic structural diagram of a second implementation of a stable and reliable food processing machine according to the present invention.

[0041] Fig.13 This is a schematic structural diagram of a third implementation of a stable and reliable food processing machine according to the present invention.

[0042] The corresponding names of the numbers in the figure are as follows: 001. Cup body assembly; 002. Main unit; 003. Processing assembly; 1. Motor; 11. Upper cover; 12. Lower cover; 2. Stator; 21. Stator slot; 3. Rotor; 310. Core body; 31. Rotor core; 32. Mounting slot; 33. Cavity; 331. Connecting section; 332. Extension section; 34. Rotor salient pole; 35. Groove; 36. Connecting hole; 37. Positioning slot; 38. Magnetic isolation bridge; 4. Fixed cage; 41. Fixed column; 410. Opening; 42. End plate; 43. Stabilizing rib; 44. Connecting column; 45. Positioning column; 46. Stabilizing hole; 47. Fan; 471. Bottom plate; 472. Fan blade; 5. Permanent magnet; 6. Motor shaft. DETAILED DESCRIPTION

[0043] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0044] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0045] In addition, in the description of the present application, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present invention. As for the positional relationships such as "upstream" and "downstream", they are based on the positional relationships when the fluid flows normally.

[0046] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0047] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0049] The present invention provides a stable and reliable food processing machine, such as Figure 1-13 As shown, the food processor comprises a main machine and a cup assembly mounted on the main machine, wherein a crushing module is arranged in the cup assembly. Figure 1As shown, the host is provided with a motor, the cup assembly is detachably connected to the host, and the motor drives the crushing module in the cup assembly to process the food in the cup assembly. The implementation of the food processor can also be as follows Fig.12 As shown, the main machine and the cup assembly are integrally arranged, and the motor directly drives the crushing assembly in the cup assembly; or Fig.13 As shown, the motor is arranged in the cup body assembly and drives the crushing module arranged in the cup body assembly. The cup body assembly is detachably connected to the host, and the host is used to support the cup body assembly. The food processor may also be other conventional settings in the art, for example, the motor is arranged in the host (head) located at the upper part of the cup body assembly, and is used to drive the crushing assembly. Such a change in mode is only a different deformation set by the food processor in the art to achieve the corresponding processing. At the same time, the processing assembly is not only a crushing tool, but also a screw for completing the extrusion processing, such as a noodle machine, a juice machine, etc. These food processing machines all use motors to realize power drive, that is, all equal changes that rely on the permanent magnet DC brushless drive described in the present invention to realize the drive are all covered by the claims of the present invention, and no examples are given here one by one.

[0050] The motor of the present invention is a permanent magnet brushless DC motor, the motor comprises a stator and a rotor, the rotor comprises a rotor core and a permanent magnet, preferably, a mounting groove is arranged on the inner side of the outer edge of the rotor core, the permanent magnet is arranged in the mounting groove, wherein the mounting groove and the permanent magnet are arranged in an even number, and as Figure 7As shown, they are arranged in sequence along the circumference of the rotor core, and the outer edge of the rotor core is also provided with a rotor salient pole protruding outward at a position relative to the permanent magnet, and a groove is formed between adjacent rotor salient poles. The rotor further includes a fixed cage integrally formed with the rotor core. Preferably, after the permanent magnet is installed on the rotor core, the fixed cage is integrally formed on the outside, and the rotor and the permanent magnet are fixedly connected by the fixed cage. The permanent magnet can be installed on the rotor core after magnetization and fixed by the fixed cage, or the permanent magnet can be installed on the rotor core and fixed by the fixed cage before magnetization. The fixed cage includes an end plate and a fixed column, the end plate is located at both ends of the rotor core, the fixed column is wrapped around the circumferential outer side of the rotor core, and is arranged at the groove, and at the same time, the outer diameter of the fixed column is not greater than the outer diameter of the rotor salient pole. The integrated fixed cage can fully wrap and position the rotor, improve the reliability of the cooperation between the permanent magnet and the rotor core, and avoid the displacement of the permanent magnet and the rotor core under the impact during long-term operation, ensuring the stable and reliable performance of the electronics over a long life cycle. The fixed cage sets a fixed column at the groove to wrap the rotor as a whole. The rotor salient poles, grooves and fixed columns cooperate with each other to increase the strength between the rotors. At the same time, by changing the air gap between the permanent magnet and the stator, the brushless motor works smoothly and reliably. A stable balance is achieved between the three, so that the brushless motor is in the best working state.

[0051] Embodiment 1.

[0052] As a first embodiment of a stable and reliable food processing machine according to the present invention, Figure 1-9 As shown, the food processor includes a cup body component 001, a main unit 002, a processing component 003 arranged in the cup body component 001, and a motor 1 arranged in the main unit 002. The motor 1 is used for the processing component 003 to process the food in the cup body component 001. The motor 1 is a permanent magnet DC brushless motor.

[0053] The motor 1 includes an upper cover 11, a lower cover 12, a stator 2 and a rotor 3. The upper cover 11 and the lower cover 12 are interlocked and form a chamber for accommodating the stator 2 and the rotor 3. Of course, it can be understood that the motor 1 can also be defined by other structures to define the stator 2 and the rotor 3, and it is not necessary to set up a complete upper cover and lower cover assembly. The motor shaft 6 is set at the center of the rotor 3, and the motor shaft 6 protrudes from the center of the upper cover 11 for power output.

[0054] The stator 2 is annular, and the rotor 3 is arranged at the center of the stator 2. The stator 2 is provided with a stator slot 21 for winding the coil. Preferably, the stator slot is set in multiples and is a multiple of 3, preferably in the range of 3 to 12, for example, 3, 6, 9, 12. The rotor 3 includes a rotor core 31 and a permanent magnet 5. The inner side of the outer edge of the rotor core 31 is provided with a mounting groove 32 for the permanent magnet to be inserted, wherein the mounting groove 32 and the permanent magnet 5 are set in an even number and are arranged in sequence along the circumference of the rotor core 31, that is, the distance from both ends of the length direction of the permanent magnet 5 to the center of the rotor 3 is the same. The N pole and the S pole of the adjacent permanent magnet 5 are arranged adjacent to each other, and the mounting groove 32 further extends to both sides of the length direction to form a cavity 33. The outer edge of the rotor core 31 is provided with a rotor salient pole 34 protruding outward at a position relative to the permanent magnet 5. It can be understood that the rotor salient pole 34 can be separated by the mounting groove 32 to form a portion on the outside of the rotor core 31. The connecting portion of the rotor core 31 located at adjacent rotor salient poles 34 shrinks toward the axis and forms a groove 35. The mounting groove 32 and the permanent magnet 5 are arranged in sequence along the circumference of the rotor, and the N pole and S pole of the permanent magnet are arranged adjacent to each other. During the rotation of the rotor, a back electromotive force waveform with better sinusoidality can be obtained between the permanent magnet and the stator coil, avoiding the jitter caused by the rotor switching magnetic poles during rotation, so that the motor can work more smoothly and reliably.

[0055] The rotor 3 also includes a fixed cage 4 that is arranged outside the rotor core 31 and is integrally formed. The fixed cage 4 is preferably integrally formed of a heat-fixing material or a thermoplastic material, and integrally wraps and fixes the rotor core 31 and the permanent magnet 5. The fixed cage 4 includes end plates 42 located at both ends of the rotor core and fixing columns 41 connecting the end plates 42 on both sides, and the fixing columns 41 are wrapped around the outer circumference of the rotor core 31 and are located at the groove 35. The end plates 42 on both sides cover the permanent magnets 5 and both ends of the rotor core 31 and form a cylindrical shape with a side wall opening 410 with the fixing columns 41. In this way, the fixed cage 4 forms an integral frame-type outer wrapping structure of the end plate 42 and the fixed column 41, and the strengthening fixing effect of the outer periphery of the end plate 42 is better, so as to prevent the outer periphery of the end plate 42 from being deformed or separated from the rotor core due to the centrifugal force when the rotor is working at high speed. At the same time, the fixed column 41 strengthens the fixing effect of the end plate 42, so that the thickness of the end plate 42 can be set thinner, reducing the overall weight and space occupied by the fixed cage, so as to increase the space share of the rotor core, and make the use efficiency of the rotor higher. Preferably, the mounting groove 32 and the permanent magnet 5 are set to 6, and the corresponding rotor salient poles 34 and grooves 35 are set to the same 6, and the fixed column 41 is set to the same 6 as the grooves 35, so that the fixed column 41 fills all the grooves 35, so that the fixed column 41 and the rotor salient pole 34 are staggered in the circumferential direction of the rotor. From the outside, the fixed cage 4 forms a cage-like structure through the fixed column 41, and the rotor salient pole leaks out from the gap of the fixed column of the cage-like structure.

[0056] The outer edge of the end plate 42 is also provided with a stabilizing rib 43, which is annular and extends to the outside of the end plate 42 along the axial direction of the rotor. Preferably, the end plates 42 on both sides are respectively provided with stabilizing ribs 43 extending outward. The rotor core 41 is provided with a through connection hole 36 along the axial direction. The fixed cage 4 also includes a connection column 44 located at the connection hole 36. The connection column 44 is integrally formed with the end plate 42 and connects the end plates 42 on both sides. The connection holes 36 are provided in plurality and can be provided with different shapes. Different connection holes can be provided according to different rotor shapes and sizes. The connection column can be integrally formed to completely fill the connection hole to form a shape that matches the connection hole. The connection hole and the connection column can strengthen the fixing effect of the fixed cage on the rotor and the permanent magnet, and can also further increase the strength of the fixed cage itself. The side wall of the installation groove 32 is also provided with a positioning groove 37. Preferably, the positioning groove 37 is arranged on the side of the installation groove 32 close to the center. The positioning groove 37 passes through the rotor core 31. The fixed cage 4 forms a positioning column 45 at the positioning groove 37. The positioning column 45 connects the end plates 42 on both sides and fits with the side wall of the permanent magnet 5 to further fix and limit the rotor core 41 and the permanent magnet 5. How to make the permanent magnet 5 be in a preset preferred position to avoid the displacement of the permanent magnet 5 and stabilize the working stability of the motor. At the same time, since the positioning column 45 is integrally formed, it can produce a better fit and fill the gap effect on the permanent magnet 5, and also reduce the setting method of filling glue between the rotor core and the permanent magnet to fix the permanent magnet, and also avoid the glue overflowing or leaking to other parts of the rotor or between the rotor and the stator to affect the normal operation of the motor. Preferably, the peripheral wall or side wall of the stabilizing rib 43 is also provided with a stabilizing hole 46, and the stabilizing hole 46 is adjusted and set according to the dynamic balancing characteristics of the rotor 3, such as the size and position of the stabilizing hole 46. Of course, the stabilizing hole 46 can be set on the stabilizing ribs on both sides or on one side and set along the outer side of the axial direction, or located on the outer side wall of the stabilizing rib 43. By setting the stabilizing hole 46, the weight of the corresponding position is reduced, so that the dynamic balance of the rotation of the rotor itself is better and the motor works more smoothly. The stabilizing rib 43 is set on the outer periphery of the end plate 42, and has a maximum rotation radius relative to the rotation axis of the rotor in the structure of the fixed cage. In this way, the stabilizing rib has a maximum state of rotational inertia. When the rotor rotates at high speed, the stabilizing rib plays the greatest balancing role on the rotor, so that the rotor works more smoothly.

[0057] The two ends of the mounting slot 32 extend outwards and form a through cavity 33. On the one hand, the fixed cage 4 can form a connecting column in the cavity 33 to further limit the permanent magnet 5. On the other hand, the adjacent cavities 33 separate the rotor core 31 into a magnetic isolation bridge 38. The cavity 33 includes a connecting section 331 and an extending section 332, wherein the connecting section 331 is connected to the mounting slot 32, and preferably has a smaller width than the mounting slot 32 and the permanent magnet 5 to limit the permanent magnet 5; the extending section 332 has an extending edge in the setting direction of the magnetic isolation bridge 38, so that the magnetic isolation bridge 38 has a smaller width. The purpose of the magnetic isolation bridge 38 is to connect the rotor core 31 and the rotor salient pole 34, but at the same time, the magnetic isolation bridge 38 will cause direct magnetic connection between adjacent permanent magnets 5, which will reduce the effective magnetic flux of the permanent magnet 5. Therefore, the direction of the prior art is to minimize the width of the magnetic isolation bridge 38 so that less magnetic flux can be connected through the magnetic isolation bridge 38. However, when the rotor 3 is rotating at high speed, the permanent magnet 5 and the rotor salient pole 34 will generate a large centrifugal force, which will directly act on the magnetic isolation bridge 38. In particular, when the magnetic isolation bridge 38 is set to be tangential or nearly tangential to the outer diameter of the rotor, the centrifugal force borne by the magnetic isolation bridge 38 acts completely in the width direction of the magnetic isolation bridge. In order to ensure that the magnetic isolation bridge will not deform under high-speed centrifugal action, it is necessary to retain at least a certain thickness. However, as mentioned above, this will affect the use efficiency of the permanent magnet, which will inevitably bring contradictions. The prior art solution usually chooses two balances, that is, to minimize it as much as possible while ensuring no deformation. In the present application, the angle between the extended part of the magnetic isolation bridge 38, that is, the length extension direction of the magnetic isolation bridge 38 and the extension line of the radius of the rotor 3 is θ, 30°≤θ≤80°. Fig. 9 As shown, such an arrangement enables when the magnetic isolation bridge 38 is subjected to the centrifugal force F, F will be decomposed into a component force Fa along the length direction of the magnetic isolation bridge 38, and a component force Fb along the width direction of the magnetic isolation bridge 38. Since the magnetic isolation bridge 38 has a sufficient length in the length direction, it can greatly withstand the corresponding force, and only needs to withstand the component force of the centrifugal force in the width direction, that is, the force it withstands is greatly reduced, and the thickness of the magnetic isolation bridge 38 can be further reduced. That is, there is no need to consider only the balance between the two, but by referring to the effect of the component force, the length direction of the magnetic isolation bridge is used to withstand the corresponding centrifugal force, so that the requirement of no deformation of the rotor is met under a smaller width condition, and the working efficiency of the permanent magnet is greatly improved.

[0058] As mentioned above, by changing the extension direction of the magnetic isolation bridge, the utilization efficiency of the permanent magnet is improved. At the same time, the groove 35 is formed on the outside of the magnetic isolation bridge 38, and the fixed cage 4 forms the fixed column 41 at the groove 35, and the fixed column 41 is used to further strengthen the fixing effect on the end plate 42. In addition, since the fixed column 41 is integrally formed at the groove 35, the fixed column 41 can also generate a force on the magnetic isolation bridge 38, and further avoid the deformation of the magnetic isolation bridge 38. In this way, a benign combination that relies on and supports each other is formed between the magnetic isolation bridge and the groove, the fixed cage and the fixed column, and each module can play an effect greater than the sum of simple monomers. Furthermore, the outer diameter of the circle formed by the rotor salient pole 34 is D, and the outer diameter of the circle formed by the fixed column 41 is d. The outer diameter of the fixed column 41 is not greater than the outer diameter of the rotor salient pole 34, so that the rotor salient pole 34 extends out of the opening 410 formed by the fixed column 41. Preferably, Dd≥1mm. The fixing column can strengthen the force on the end plate and the magnetic isolation bridge. At the same time, in order to ensure that the magnetic air gap between the rotor and the stator is small enough, the gap between the rotor and the stator needs to be set small enough. When the outer diameter of the fixing column is close to the outer diameter of the rotor salient pole, the fixing column is more susceptible to the centrifugal force and deforms outward when rotating at high speed (although the amount of such deformation is usually small), but such deformation will cause mutual friction between the fixing column and the stator, which will affect the normal operation of the motor. The difference in the outer diameter of the rotor salient pole and the fixing column is set to be not less than 1mm, which can fully ensure the stability of the rotor operation and the stability and reliability of the magnetic air gap, making the rotor easy to manufacture. Of course, the characteristics of the fixing column can also be improved by improving the material properties of the fixing cage to avoid deformation of the fixing column. In this way, the difference in the outer diameter of the rotor salient pole and the outer diameter of the fixing column can be further compressed.

[0059] The angle formed by the single fixed column 41 in the circumferential direction is α, and the angle formed by the single rotor protrusion 34 in the circumferential direction is β, wherein 1 / 4≤α / β≤1 / 2. The purpose of setting the fixed column is mainly to enhance the fixing force on the end plate and the magnetic isolation bridge, while at the same time the fixed column must avoid affecting the permanent magnet. If the wrapping angle (i.e. the angle formed by the fixed column in the circumferential direction) is set too large, the rotor air gap will be reduced, it will be difficult to process and the working state will be unstable. The fixed column is also prone to friction with the stator under the action of high-speed centrifugation. If it is set too small, it will not be able to effectively play a fixing role, and the air gap between the groove and the stator will be too large, which is easy to generate noise.

[0060] Compared with the prior art that only sets an integrally formed plastic frame, the present application wraps an integrally formed fixed cage on the outside of the rotor, and the fixed cage sets a fixed column on the outside of the rotor. The fixed column cooperates with the groove and the rotor salient pole, which has a better effect than the superposition of a single function. The fixed cage sets a fixed column at the groove to wrap the rotor as a whole, increase the strength of the fixed cage itself, so that the fixed cage can better fix and limit the rotor core and the permanent magnet, and avoid the fixed cage in the prior art that the peripheral edge is subjected to a large centrifugal force when the fixed cage is fixedly connected only by the central connecting column to produce deformation and affect the strength of the fixed cage. Furthermore, the outer diameter of the fixed column is not greater than the outer diameter of the rotor salient pole, ensuring that the air gap between the rotor salient pole and the stator is small enough. In this way, the rotor salient pole, the groove and the fixed column cooperate with each other to increase the strength between the rotors, and at the same time, by changing the air gap between the permanent magnet and the stator, the brushless motor works smoothly and reliably, and a stable balance is achieved between the three, so that the brushless motor is in the best working state.

[0061] It is understandable that the moment of inertia of the end plate can be increased by increasing the thickness of the end plate without providing a separate stabilizing rib. Alternatively, the end plate can be configured in a transitional manner of being thin in the center and thick at the periphery to form the stabilizing rib.

[0062] It is understandable that the number of the fixing columns is a multiple of the number of the grooves and is greater than 1. For example, when the number of the grooves is 6, the number of the fixing columns can be 2 or 3, and they are arranged symmetrically in the circumferential direction. This ensures that the fixing columns are in a rotationally balanced state during the rotation of the rotor.

[0063] It is understandable that the number of the mounting slots and permanent magnets may also be 4, 8, etc.

[0064] It can be understood that the stabilizing holes can also be directly arranged on the side wall or peripheral wall of the end plate.

[0065] Embodiment 2.

[0066] As a second embodiment of the stable and reliable food processing machine of the present invention, Fig.10 As shown, compared with the first embodiment, the rotor core described in this embodiment includes an iron core body and rotor salient poles. It should be noted that the specific first embodiment and the second embodiment described separately do not mean that the two embodiments are completely independent of each other, but are only for the purpose of specifically illustrating two preferred technical solutions, and the technical features and technical solutions of the two embodiments are common and can be used for reference.

[0067] like Fig.10As shown, the rotor core includes a split core body 310 and a rotor salient pole 34. An installation groove 32 is provided on the outer peripheral side of the core body 310, and the installation groove 32 is used to install the permanent magnet 5. The rotor salient pole 34 is provided outside the permanent magnet 5, thereby forming a cavity 33 on both sides of the installation groove 32, the permanent magnet 5 and the rotor salient pole 34. An integrally formed fixed cage 4 is provided outside the rotor core, and the fixed cage 4 forms the fixed column 41 at the cavity 33, and the fixed column 41 fixes and limits the permanent magnet 5 and the rotor salient pole 34. The core body and the rotor salient pole are disconnected, so that the adjacent permanent magnets can no longer be directly connected magnetically through the magnetic isolation bridge, so that the magnetic flux of the permanent magnet passes more through the rotor salient pole and through the stator, thereby improving the magnetic utilization efficiency of the permanent magnet.

[0068] Embodiment three.

[0069] As a third embodiment of the stable and reliable food processing machine of the present invention, Fig.11 As shown, compared with the first embodiment, the fixed cage in this embodiment also includes an integrally formed fan. It should be noted that the specific first embodiment and the second embodiment described separately do not mean that the two embodiments are completely independent of each other, but are only for the purpose of specifically illustrating two preferred technical solutions, and the technical features and technical solutions of the two embodiments are common and can be used for reference.

[0070] Since the coil of the motor will generate heat during operation, in order to better dissipate the heat of the motor coil, it is usually necessary to set a fan on the rotor of the motor to drive the airflow through the coil to better dissipate the heat of the coil. The existing scheme usually installs a fan at the end of the motor shaft of the rotor, and the fan and other parts of the rotor are only in a mounting relationship. In the present application, the fixed cage is used to form an integral fan 47, wherein the fan 47 is formed by the end plate of the fixed cage 4 located at the end of the motor shaft 6 (the front end or head end, the end refers to the output end of the motor shaft used to drive the processing, wherein the end used to directly drive the processing component is called the front end or head end, and the other end opposite is called the end end) extending radially outward. Preferably, the fan 47 includes a base plate 471 and blades 472. When the rotor rotates, the blades 472 drive the airflow to be discharged radially outward. In this way, in combination with the motor cavity formed by the upper cover and the lower cover outside the motor, the air flows into the motor cavity along the radial direction of the upper cover or the lower cover, passes through the rotor and the stator of the motor, and then flows out of the motor cavity along the radial direction of the upper cover or the lower cover under the driving action of the fan. Therefore, the airflow does not need to occupy too much dimensional space in the axial direction of the motor, and can compress the height of the motor in the axial direction to achieve the design requirements of the motor being light and thin. The fan and the fixed cage are integrally formed to meet the functional requirements of the motor heat dissipation. At the same time, the integrally formed fan, especially the one-piece fan, is formed by extending the end plate, and the strength is guaranteed, and the fan can be set to a thinner size while meeting the strength requirements of the fan. It also avoids the error generated when the fan is assembled with the rotor, and when the fan is assembled on the motor shaft, it is easy to fall off the motor shaft and affect the normal operation of the motor shaft.

[0071] It can be understood that the fixed cage is integrally formed with a separate fan at the end of the motor shaft and is fixedly connected to the end plate at the end.

[0072] It can be understood that the fan is only provided with fan blades, and the fan blades drive the airflow to flow along the axial direction of the motor.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made according to the present invention are covered by the scope of the claims of the present invention and will not be listed one by one here.

Claims

1. A stable and reliable food processing machine, comprising a permanent magnet DC brushless motor and a processing assembly driven by the motor, wherein the motor comprises a stator and a rotor, and the rotor comprises a rotor core and a permanent magnet, wherein: An installation groove for inserting the permanent magnet is provided on the inner side of the outer edge of the rotor core, the installation grooves are an even number and are arranged in sequence along the circumference of the rotor core, an outwardly protruding rotor salient pole is provided at the outer edge of the rotor core relative to the permanent magnet, and a groove is formed between adjacent rotor salient poles, the rotor also includes a fixed cage arranged outside the rotor core and integrally formed, the fixed cage includes end plates located at both ends of the rotor core and fixed columns located on the outer side wall of the rotor core and connecting the end plates at both ends, the fixed column is located at the groove and the outer diameter of the fixed column is not greater than the outer diameter of the rotor salient pole.

2. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The outer edge of the end plate is also provided with a stabilizing rib, which is annular and extends toward the outside of the end plate along the axial direction of the rotor, and the fixing column connects the stabilizing ribs at both ends.

3. A stable and reliable food processing machine as claimed in claim 2, characterized in that: The circumferential side wall or the top wall of the stabilizing rib is provided with a stabilizing hole.

4. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The rotor core is provided with a connecting hole located inside the mounting groove and penetrating in the axial direction, and the fixing cage includes a connecting column located in the connecting hole and connecting the end plates at both ends.

5. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The inner side wall of the installation groove is provided with a positioning groove, and the fixing cage includes a positioning column which is located in the positioning groove and connects the end plates at both ends, and the positioning column is in contact with the permanent magnet.

6. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The angle formed by a single fixing column in the circumferential direction is α, the angle formed by a single rotor protrusion in the circumferential direction is β, and 1 / 4≤α / β≤1 / 2.

7. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The outer diameter of the fixing column is d, and the outer diameter of the rotor salient pole is D, where Dd≥1 mm.

8. A stable and reliable food processing machine as claimed in claim 1, characterized in that: Cavities are provided at both ends of the installation slots, and the rotor core is located between the cavities of two adjacent installation slots to form a magnetic isolation bridge. The angle between the extended part of the magnetic isolation bridge and the extended line of the rotor radius is θ, 30°≤θ≤80°.

9. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The rotor core includes a core body and a rotor salient pole, the rotor salient pole is fixed to the outside of the permanent magnet through the fixing column, cavities are provided at both ends of the mounting slot, the fixing column passes through the cavity and connects the cavities of two adjacent mounting slots to form a magnetic isolation bridge between the two permanent magnets.

10. A stable and reliable food processing machine as claimed in claim 1, characterized in that: The rotor further comprises a fan integrally formed with the fixed cage, the fan radially extending outward along an end plate located at the end of the motor, and the fan comprises a fan body and fan blades.

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