Food processor reliable in operation

Abstract

A food processor reliable in operation comprises a main machine, the main machine comprises a machine shell, a direct-current brushless motor and a control circuit board, the direct-current brushless motor and the control circuit board are arranged in a main machine installation cavity of the main machine, and the direct-current brushless motor has the working process with the rotating speed ranging from 300 r / min to 5000 r / min; the control circuit board comprises an EMC (Electro Magnetic Compatibility) module and a switching power supply module, the EMC module is connected among an external power supply, the switching power supply module and the motor driving module, the EMC module comprises a differential mode suppression module and a common mode suppression module, the common mode suppression module comprises a common mode inductor, the switching power supply module comprises an electrolytic capacitor, and the electrolytic capacitor is arranged within the range of 4cm of the common mode inductor; a magnetic ring is further arranged in the host installation cavity and arranged on a connecting line connecting the direct-current brushless motor and the motor driving module in a sleeving mode. The common-mode inductor and the magnetic ring are arranged to jointly restrain disturbance signals of the food processor, the electrolytic capacitor is prevented from being affected by too high temperature rise when the common-mode inductor works independently, protection on the electrolytic capacitor is improved, and the product runs reliably.

Description

Technical Field

[0001] The present application relates to the field of food processing, and in particular to a food processor using a brushless DC motor to provide power. Background Art

[0002] Food processors are used by users to cook food and have become a necessity in people's lives. With the improvement of people's living standards, the processing requirements for food are becoming more and more refined. For example, existing food processors already have functions such as making soy milk, squeezing juice, making rice paste, mincing meat, smoothies, and kneading noodles. Although these functions can rely on different professional processing equipment, this will require users to configure a variety of different equipment to meet different functional requirements. Being able to use a food processor to meet multi-functional processing has become a demand of people. Since various cooking processes require different processing speeds, the speed is usually adjusted in a large range of 300rpm to 30000rpm (rpm, revolutions / minute). One existing solution is to set a smaller adjustment range for the motor, and different functions of processing use different reduction devices to achieve the corresponding speed requirements; another existing solution is to directly use a motor that can be adjusted in a wide range to drive directly, among which a DC brushless motor that can achieve a wide range of adjustment is a better choice. However, for a DC brushless motor, a more complex control scheme is required to drive the DC brushless motor to work according to the preset speed and torque. At the same time, the multifunctional food processing process also requires the use of control circuits to realize corresponding functions, thus making the control circuit board structure of the food processing machine more and more complicated.

[0003] Such a food processor will become a strong source of electromagnetic interference (EMI) during operation. If it is not controlled, the electromagnetic interference of the food processor will be transmitted to the power grid and interfere with the normal operation of other networked devices. In order to solve the electromagnetic interference generated by the food processor, a separate electromagnetic compatibility (EMC) module needs to be set up in the food processor to filter out the electromagnetic interference generated and avoid external influence. Usually, EMC will include a common mode suppression module, wherein the common mode suppression module includes a common mode inductor. In order to control the food processor and the motor, the control circuit board will also be provided with a switching power supply module, wherein the switching power supply module includes an electrolytic capacitor. Since the electrolytic capacitor is sensitive to the influence of temperature, when the temperature rises, the current liquid of the electrolytic capacitor will gradually evaporate, resulting in a decrease in capacitance or even failure, and the evaporation speed will increase with the increase in temperature. When the common mode inductor suppresses and processes the common mode signal, it will heat itself, especially when the interference source generates a stronger interference signal, such as when the DC brushless motor is working at a lower speed, the common mode inductor will reach a higher temperature. Therefore, it is necessary to avoid the influence of the heat of the common-mode inductor on the electrolytic capacitor. The conventional approach is to increase the distance between the two, which will increase the area and volume of the control circuit board itself, and correspondingly increase the volume of the host.

[0004] As a leader in the field of food processing machines, especially in the field of wall breaking machines, the applicant continues to be committed to product upgrades and improvements in user experience. In order to provide users with a thin and light food processing machine, it is necessary to compress the volume and weight of the main machine as much as possible. However, due to the settings of the motor and the control circuit board, the volume of the main machine cannot be compressed to the extreme. An existing conventional solution is to dissipate heat from the control circuit board by setting a separate heat dissipation structure to reduce the volume of the control circuit board itself; another solution is to remove the EMC module from the control circuit board and set it as a separate EMC circuit board to separate the common-mode inductor from the electrolytic capacitor. However, the above solutions will bring about structural complexity and increased costs, and cannot meet the needs of more users. At the same time, the complexity of the structure also leads to reduced reliability, which will bring the risk of poor working stability of the food processor and leakage of electromagnetic interference. Summary of the invention

[0005] The object of the present invention is to provide a food processing machine with reliable operation, which adopts a DC brushless motor and can directly output a rotation speed of 300 to 5000 rpm and provide a corresponding working process, and can limit the common mode inductor and electrolytic capacitor to a distance range of 4 cm, thereby providing users with a light and reliable processing equipment.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a food processing machine with reliable operation, comprising a main machine and a processing module, the main machine comprising a casing, a DC brushless motor and a control circuit board, a main machine installation cavity is formed inside the casing, the DC brushless motor and the control circuit board are arranged in the main machine installation cavity, wherein the DC brushless motor includes a working process with a rotation speed of 300 to 5000 rpm; the control circuit board includes an EMC module, a switching power supply module and a motor drive module, the EMC module is connected between an external power supply and the switching power supply module and the motor drive module, the EMC module includes a differential mode suppression module and a common mode suppression module, the common mode suppression module includes a common mode inductor, the switching power supply module includes an electrolytic capacitor, wherein the electrolytic capacitor is arranged within 4 cm of the common mode inductor; a magnetic ring is also arranged in the main machine installation cavity, and the magnetic ring is sleeved and connected to the connecting line between the DC brushless motor and the motor drive module.

[0007] Preferably, the differential mode suppression modules and the common mode suppression modules are respectively provided with no more than two stages.

[0008] Preferably, the differential mode suppression module includes a primary differential mode suppression module and a secondary differential mode suppression module, the common mode suppression module is set as a primary level, and the common mode suppression module is set between the primary differential mode suppression module and the secondary differential mode suppression module.

[0009] Preferably, the number of the common-mode inductor is 1, the common-mode inductor is adjacent to the switching power supply module, and the switching power supply module includes at least 2 electrolytic capacitors located within 4 cm of the common-mode inductor.

[0010] Preferably, the control circuit board is arranged in a square shape, the EMC module is arranged at one corner of the control circuit board, the EMC module is provided with a connection portion connected to an external power supply, the switching power supply module is arranged in an area adjacent to the EMC module, and the common-mode inductor and the electrolytic capacitor are located on the same side of the control circuit board.

[0011] Preferably, the connecting wires of the brushless DC motor are three-phase wires U, V, and W, and the three-phase wires U, V, and W are wound into the magnetic ring in the same direction and with the same number of turns.

[0012] Preferably, the magnetic ring is a hollow cylinder made of magnetic material, and the outer diameter of the magnetic ring is not less than 2 cm.

[0013] Preferably, the inductance of the common mode inductor is not greater than 10 mH.

[0014] Preferably, the processing module includes a heating element, the power of the brushless DC motor is not greater than 1000W, the power of the heating element is not greater than 1000W, the differential mode suppression module includes an X capacitor, and the capacitance of the X capacitor is 0.22uF-2uF.

[0015] Preferably, the food processor further comprises a second magnetic ring, and the second magnetic ring is sleeved on a power line connecting the EMC module to the outside.

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

[0017] 1. A food processor using a brushless DC motor can directly output a wide speed range, especially in the same processing process, it can simultaneously achieve high speeds such as 10,000 to 30,000 rpm, and low speeds such as 300 to 1,000 rpm, to meet the diversified processing of the food processor. Under the premise of meeting the above motor operation, the brushless DC motor itself and the control module used to control the brushless DC motor will generate large electromagnetic interference, and an EMC module needs to be set to filter the electromagnetic interference to avoid affecting other networked products. At the same time, the control circuit board also needs to be equipped with a switching power supply module to provide outputs such as DC power to each component, and due to the increase in the control unit, the switching power supply needs to continuously increase the number of electrolytic capacitors to meet the demand. Under the premise of the above requirements, it is necessary to ensure that the electromagnetic interference is not leaked, and it is also necessary to set the common mode inductor and electrolytic capacitor on the control circuit board at the same time, and set the electrolytic capacitor within 4 cm of the common mode inductor to reduce the volume of the control circuit board. In order to ensure the reliable operation of the common-mode inductor and the electrolytic capacitor and avoid the failure of the electrolytic capacitor when the common-mode inductance is too high, the present application further arranges a magnetic ring, and sleeves the magnetic ring on the connection line between the DC brushless motor and the motor drive module. In this way, the common-mode interference generated by the DC brushless motor during operation can be greatly consumed when passing through the magnetic ring, especially when the DC brushless motor itself is in a high-frequency working environment. The magnetic ring can greatly suppress the electromagnetic interference generated by the DC brushless motor itself, thereby greatly reducing the suppression signal that needs to be processed by the common-mode inductor, so that the temperature increase of the common-mode inductor during operation is greatly reduced, that is, the reliability of the common-mode inductor itself is ensured, and the heat of the common-mode inductor is prevented from affecting the normal operation of the electrolytic capacitor, so as to achieve that when the common-mode inductor and the electrolytic capacitor are arranged on the same control circuit board, the distance between the common-mode inductor and the electrolytic capacitor is as small as possible, so as to reduce the volume of the control circuit board and ultimately achieve the purpose of making the food processor thin and light.

[0018] 2. Theoretically, the differential mode suppression module and the common mode suppression module of the EMC module can be set to multiple levels, for example, by setting 4, 5 or even more levels of differential mode suppression modules and common mode suppression modules, the electromagnetic interference can be filtered step by step to achieve the purpose of reliable operation of the food processing machine, but this will increase the cost and increase the volume of the EMC module, which is contrary to the original intention of the applicant to pursue a light and efficient food processing machine. In the present application, due to the addition of a magnetic ring, the differential mode suppression module and the common mode suppression module can be set to no more than two levels. First, the magnetic ring is used to isolate the primary electromagnetic interference signal source DC brushless motor and filter out a large number of interference signals, especially common mode interference signals. The interference signals that need to be processed by the common mode suppression module on the control circuit board, especially the common mode inductor, are reduced, and the heat generation of the common mode inductor itself is controlled. Under the premise of not adding multiple levels of common mode suppression modules, the electromagnetic interference control of the food processing machine is realized, and the volume of the control circuit board is also reduced.

[0019] 3. Since the differential mode suppression module does not need to be equipped with heat-prone components such as common mode inductors, the differential mode suppression module can be set to two levels, including a first-level differential mode suppression module and a second-level differential mode suppression module, while the common mode suppression module is only set to one level. With the dual effects of the magnetic ring and the common mode inductor, especially the common mode inductor directly acting on the lead-out line of the brushless DC motor, it is ensured that when there is only one level of common mode suppression module, the electromagnetic interference can still be filtered out well. The common mode suppression module is set between the first-level differential mode suppression module and the second-level differential mode suppression module, so that the magnetic ring, the first-level differential mode suppression module, the common mode suppression module, and the second-level differential mode suppression module actually play the role of multi-stage filtering, achieving a better filtering effect.

[0020] 4. The differential mode suppression module is usually composed of X capacitors, which do not require too large a volume, nor will they generate too much heat, and are not sensitive to the number of settings. Common-mode inductors usually have a large volume and generate heat. Although increasing the number of common-mode inductors can achieve the purpose of mutual sharing and reducing the temperature of each, the first stage usually has a greater filtering purpose, and the first-stage common-mode inductors will still generate a lot of heat. Setting one common-mode inductor can minimize the volume of the control circuit board on the basis of suppressing the common-mode signal. Directly placing the common-mode inductor adjacent to the switching power supply module avoids signal interference between other modules on the switching power supply module, and ensures that the output of the switching power supply module is stable and reliable. Due to the dual setting factors of the magnetic ring and the common-mode inductor, it can be ensured that even if the multiple electrolytic capacitors in the switching power supply module are set within 4cm of the common-mode inductor, they will not be affected by the heating of the common-mode inductor.

[0021] 5. The shape of the host is usually set to be square, and the square shape of the circuit board can also save waste and reduce costs when it is made. The EMC module is set at one corner of the control circuit board, and the connection line between the control circuit board and the outside can be connected to the EMC module first. In this way, the other modules inside the host are isolated from the external power grid through the EMC module, that is, the electromagnetic disturbance generated by each module of the food processing machine is prevented from leaking to the power grid, and the electromagnetic disturbance of the external power grid is prevented from affecting the normal operation of the host. The EMC module and the switching power supply module are set in adjacent areas. The EMC module can isolate internal and external interference and ensure the output stability of the switching power supply module. The common-mode inductor and the electrolytic capacitor are located on the same side of the control circuit board, which can avoid the common-mode inductor and the electrolytic capacitor being located on both sides of the control circuit board. They will occupy a large space volume on both sides, affecting the normal installation of the control circuit board and causing the volume of the host to increase.

[0022] 6. The brushless DC motor is connected to the control module of the control circuit board through three-phase lines U, V, and W. The three-phase lines U, V, and W are wound into the magnetic ring in the same direction and with the same number of turns. The common-mode signals generated between the three-phase lines can cancel each other out when passing through the magnetic ring, thereby achieving the purpose of suppressing common-mode interference signals.

[0023] 7. The magnetic ring is set on a hollow cylinder, and the outer diameter of the magnetic ring is not more than 2cm. The connecting wire of the motor is passed through and wound around the hollow cylinder of the magnetic ring. The integrated magnetic ring can ensure the best suppression of common mode signals. On the basis of selecting appropriate materials, for example, a magnetic ring made of a magnetic material of Kc500 can be selected, which has sufficient resistance when suppressing high-efficiency signals and can achieve high-frequency filtering efficiently. The size is not more than 2cm, and it will not occupy too much volume, which can ensure the purpose of setting the food processor light and thin.

[0024] 8. The working conditions of the food processor determine that the motor of the food processor does not need to be set with too large power and control factors, and it only needs to meet the normal operation of the DC brushless motor within a wide speed range. Therefore, the inductance value of the common mode inductor is set to no more than 10mH, which can meet the suppression effect of the common mode inductor, and at the same time does not need to be set too large, thereby reducing the volume of the control circuit board.

[0025] 9. The food processor is further provided with a heating element, so that the food processor can also realize heating power synchronously under the premise that the DC brushless motor drives the crushing process, thereby ensuring that the food processor can realize a wider range of food processing. Since the food processor of the present application is usually aimed at home users, the processing capacity only needs to meet the needs of ordinary home users, and there is no need to set an excessively large processing capacity. Therefore, the power of the DC brushless motor is set to be no more than 1000W, and the power of the heating element is no more than 1000W. By setting the magnetic ring and the common-mode inductor, the common-mode signal generated by the food processor can be fully suppressed. The differential-mode signal generated can be suppressed by the X capacitor of the differential-mode suppression module. Due to the limitations of the food processor's own conditions, it is only necessary to limit the capacitance value of the X capacitor to 0.22uF-2uF to meet the suppression requirements.

[0026] 10. A second magnetic ring is further provided, and the second magnetic ring is sleeved on the power line connected between the EMC module and the outside, which can further filter possible leakage, or the influence of various components inside the host on the power line, so that the external interference of the food processor is reduced to a controllable range. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the food processing machine of the present invention.

[0028] Figure 2 The figure is a functional block diagram of the control circuit board of the food processing machine of the present invention.

[0029] Figure 3 This is a layout diagram of a control circuit board of the food processing machine of the present invention.

[0030] Figure 4 This is a functional diagram of the connection between the control circuit board and the motor of the food processor of the present invention.

[0031] Figure 5 It is a schematic structural diagram of the control circuit board of the food processing machine of the present invention.

[0032] Figure 6 This is a schematic diagram of the principle of the EMC module of the food processing machine of the present invention.

[0033] Figure 7 This is a schematic diagram of an electromagnetic interference test of the food processing machine of the present invention before the magnetic ring is installed.

[0034] Figure 8 This is a schematic diagram of an electromagnetic interference test of the food processing machine of the present invention after a magnetic ring is provided.

[0035] The corresponding names in the attached drawings are as follows:

[0036] 001. cup body assembly; 002. crushing knife; 003. main unit; 004. brushless DC motor; 100. EMC module; 101. common mode inductor; 110. common mode suppression module; 121. first differential mode suppression module; 122. second differential mode suppression module; 200. rectifier filter module; 300. switching power supply module; 301. electrolytic capacitor; 400. motor drive module; 500. MCU module; 600. heating drive module; 701. magnetic ring; 702. second magnetic ring. DETAILED DESCRIPTION

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] The food processing machine of the present invention is reliable in operation. Figure 1-8As shown, the food processor includes a host and a processing module, and the processing module includes a cup body assembly and a crushing knife. It should be noted that the host and the processing module are only distinguished from each other in terms of function, and the host and the processing module of the food processor are not limited to being separately set. The host can be separately set from the processing module, or the host and the processing module can be set as one. The host includes a housing, a DC brushless motor and a control circuit board. A host installation cavity is formed in the housing, and the DC brushless motor and the control circuit board are arranged in the host installation cavity. When the host and the processing module are separately set, the processing module is arranged outside the host; when the host and the processing module are arranged as one, the processing module can also be arranged in the host installation cavity of the housing. Based on the functional requirements of the food processor, the DC brushless motor is set to provide power for the processing module, and low-speed output can be directly performed. Therefore, the DC brushless motor of the food processor includes a working process with a speed of 300 to 5000 rpm (rpm, revolutions per minute). The control circuit board includes an EMC module, a switching power supply module and a motor drive module. The EMC module is connected between the external power supply and the switching power supply module and the motor drive module. That is, after the external mains power supply is connected to the host, it first passes through the EMC module and then flows to the switching power supply module, the motor drive module, etc. In this way, the disturbance of the external power supply can be prevented from affecting the normal operation of the control circuit board, and the electromagnetic disturbance generated in the host can be isolated through the EMC module to avoid affecting the external power grid. The EMC module includes a differential mode suppression module and a common mode suppression module. The common mode suppression module includes a common mode inductor. The switching power supply module includes an electrolytic capacitor, wherein the electrolytic capacitor is arranged within 4 cm of the common mode inductor. The brushless DC motor can meet various working conditions of the food processor, and the speed range can be adjusted within the range of 300 to 30000 rpm. In this way, the motor drive module itself generates more electromagnetic disturbances. When these electromagnetic disturbances pass through the common mode inductor, the common mode inductor generates heat when suppressing the electromagnetic disturbances. The electrolytic capacitor of the switching power module is particularly susceptible to the influence of heat, therefore, it is necessary to avoid the heat generated by the common-mode inductor from affecting the electrolytic capacitor. However, the switching power module needs to be arranged adjacent to the EMC module to facilitate the output of the low-voltage power supply, and at the same time, it is also necessary to avoid the control circuit board itself from being too large. Therefore, it is necessary to arrange the electrolytic capacitor within 4 cm of the common-mode inductor, thereby increasing the influence of the common-mode inductor on the electrolytic capacitor. Although it is also possible to cool down by arranging a multi-stage differential mode suppression module and a common-mode suppression module, and arranging a separate heat dissipation structure such as a fan, these will all lead to an increase in the volume of the control circuit board and an increase in cost, which does not meet the purpose of providing a portable food processor in this application. The contradiction between the common-mode inductor in suppressing the heat generation of the brushless DC motor at work and the electrolytic capacitor at a close distance is urgently needed to be solved by the present invention.Therefore, further, a magnetic ring is also provided in the main engine installation cavity, and the magnetic ring is sleeved and connected to the connection line between the DC brushless motor and the motor drive module. Since the magnetic ring is directly sleeved on the connection line between the DC brushless motor and the motor drive module, the electromagnetic disturbance generated by the DC brushless motor is greatly suppressed when passing through the magnetic ring, and does not need to flow to the control circuit board and pass through the EMC module, thereby improving the electromagnetic disturbance suppression capability of the food processor itself, and does not need to add a suppression module of the EMC module, and also weakens the signal that needs to be suppressed by the common-mode inductor, thereby greatly reducing the heat generation of the common-mode inductor itself, avoiding the influence of the common-mode inductor heating on the electrolytic capacitor, so that the common-mode inductor and the electrolytic capacitor can be set within a smaller distance range, and finally realize the volume compression of the control circuit board and the main engine.

[0044] As a reliable food processing machine according to the present invention, Figure 1-8 As shown, the food processor includes a main unit 003 and a processing module, the processing module includes a cup body assembly 001 and a crushing blade 002 arranged in the cup body assembly 001, the main unit 003 includes a housing, a DC brushless motor 004 and a control circuit board, a main unit installation cavity is formed inside the housing, and the DC brushless motor 004 and the control circuit board are arranged in the main unit installation cavity. The DC brushless motor 004 is used to drive the crushing blade 002 to work so as to crush the food placed in the cup body assembly 001. Of course, the food processor can also be provided with other processing modules, such as a screw for extruding food, a die head for forming, etc. The DC brushless motor includes a working process with a rotation speed of 300 to 5000 rpm to meet the wide range of working requirements of the food processor.

[0045] like Figure 2As shown, the control circuit board includes an EMC module 100, a switching power supply module 300 and a motor drive module 400. Preferably, the control circuit board is also provided with a rectifier filter module 200, an MCU module 500 and a heating drive module 600. The processing module is also provided with a heating element for heating the food in the cup body component 001. The EMC module 100 is connected between the external mains and other modules, and the rectifier filter module 200 is respectively connected between the EMC module 100 and the motor drive module 400. The rectifier filter module 200 rectifies the mains voltage and provides it to the motor drive module 400. The motor drive module includes an IPM module circuit for driving the DC brushless motor 004. The switching power supply module 300 is connected to the EMC module 100 and provides a working power supply to the food processor, such as the working power supply of the MCU module 500. The heating drive module 600 is connected to the heating element and controls the heating element to heat the food under the drive of the MCU module. The MCU module 500 is used to control the motor driving module 400 and the heating driving module 600 to operate the brushless DC motor and the heating element, and can also receive external information to perform corresponding processing and provide feedback.

[0046] like Figure 3 As shown, the control circuit board is set to be square (the square here means that the control circuit board is square in the size of the space occupied by the control circuit board, and it is not limited to the square defined by mathematics. In the specific structure, the control circuit board includes straight edges, and local protrusions or rounded corners can be set at other positions). The EMC module 100 is set at one corner of the control circuit board, which is set here Figure 3 The upper right corner of the direction shown, at which position a terminal connected to the outside is also provided, so as to be connected to the external mains electricity. A switching power supply module 300 is provided on the lower side of the EMC module, and the switching power supply module 300 is provided with a plurality of electrolytic capacitors 301. A heating drive module 600 is provided on the middle upper side of the control circuit board, and the heating drive module 600 is provided with a terminal connected to the heating element. An MCU module is provided on the middle lower side of the control circuit board, and the MCU module 500 is adjacent to the switching power supply module 300, so that the switching power supply module 300 supplies power to the MCU module 500. Rectification and filtering modules 200 and motor drive modules 400 are provided in other areas of the control circuit board.

[0047] like Figure 3-6As shown, the EMC module includes a differential mode suppression module and a common mode suppression module 110. Preferably, the common mode suppression module is set as a first level, and the differential mode suppression module is set as a second level. The differential mode suppression module includes a first differential mode suppression module 121 and a second differential mode suppression module 122. The common mode suppression module 110 is arranged between the first differential mode suppression module 121 and the second differential mode suppression module 122. The first differential mode suppression module 121 and the second differential mode suppression module 122 are respectively provided with X capacitors. The common mode suppression module 110 includes a common mode inductor 101 and two Y capacitors, and the common mode inductor 101 is set as one. The electrolytic capacitor 301 is arranged within 4 cm of the common mode inductor 101. Preferably, at least two electrolytic capacitors 301 are arranged within 4 cm of the common mode inductor 101, for example, three electrolytic capacitors are arranged within 4 cm.

[0048] During the operation of the brushless DC motor 004, the rectifier filter module 200 and the motor drive module 400 provide a high-frequency power supply to the brushless DC motor 004, so that the brushless DC motor 004 generates a large amount of disturbance signals when working and feeds back to the control circuit board. In order to prevent the disturbance signals from leaking to the external power grid via the control circuit board, the EMC module is required to suppress and eliminate the disturbance signals. When the EMC module 100 eliminates the disturbance signals, especially when the common mode suppression module 110 is working, the common mode inductor 101 is prone to heat and temperature rise. In this embodiment, the inductance value of the common mode inductor is set to be no more than 10mH (millihenry). However, when the common mode inductor 101 suppresses the disturbance signals, it still generates heat and temperature rises, which affects the electrolytic capacitor 301.

[0049] The host installation cavity is also provided with a magnetic ring 701 for protecting the electrolytic capacitor, and the magnetic ring 701 is sleeved on the connecting line connecting the DC brushless motor 004 and the motor drive module 400. Among them, the connecting line between the DC brushless motor 004 and the motor drive module 400 is a U, V, W three-phase line, and the U, V, W three-phase line is wound into the magnetic ring 701 in the same direction and with the same number of turns. This is mainly because the magnetic ring 701 is used to suppress the common-mode interference signal generated by the DC brushless motor, and is wound into the magnetic ring in the same direction and with the same number of turns to ensure the best suppression effect of the common-mode interference of the three phases. Further, the magnetic ring is a hollow cylinder made of magnetic material, and the outer diameter of the magnetic ring 701 is not more than 2cm. The U, V, W three-phase lines pass through the hollow of the magnetic ring and are wound around the hollow cylinder of the magnetic ring. The outer diameter of the magnetic ring 701 is set to be no more than 2 cm, and the magnetic ring does not occupy too much volume, but can suppress the common-mode interference signal of the DC brushless motor. Since the magnetic ring is directly arranged on the connecting line of the DC brushless motor, the interference signal of the DC brushless motor can be suppressed better, thereby avoiding a large number of interference signals from being directly eliminated by the common-mode suppression module 110, and also avoiding excessive heating and temperature rise of the common-mode inductor 101, and finally achieving the guarantee of the electrolytic capacitor. Such a setting does not require the setting of a complex EMC module, that is, there is no need to set up a multi-stage common-mode suppression module and a differential mode suppression module, and the common-mode inductor and the electrolytic capacitor can be set at a close distance without increasing the area and volume of the control circuit board itself, and also ensuring that the volume of the main unit of the food processor is light and thin.

[0050] Preferably, the power of the brushless DC motor 004 is not more than 1000W, and the power of the heating element is not more than 1000W. Such a setting is mainly based on the processing environment of the food processor. For general household products, setting a brushless DC motor of not more than 1000W and a heating element of not more than 1000W can meet the needs of most cooking conditions. Setting a motor and a heating element with too large power can meet more needs, but it will cause a waste of resources. Based on the setting and processing conditions of the heating element and the brushless DC motor, the capacitance of the X capacitor of the differential mode suppression module is set at 0.22uF-2uF, which can meet the suppression effect of the differential mode suppression module on the differential mode interference signal.

[0051] As mentioned above, when the food processor is in the process of processing, the MCU module receives the user's operation signal and controls the brushless DC motor and the heating element to work according to preset conditions. In the working process of the brushless DC motor and the heating element, especially in the working process of the brushless DC motor, a large amount of disturbance signals will be generated. In order to prevent the disturbance signal from being transmitted to the external power grid, an EMC module is set to filter the above disturbance signal. In the process of processing the disturbance signal, the common mode inductor of the EMC module, especially the common mode suppression module, will generate heat and heat up in the process of eliminating the disturbance signal (the common mode inductor is equivalent to the resistor when eliminating the disturbance signal), and other components of the control circuit board, especially the electrolytic capacitor in the switching power module, are susceptible to high temperature. Therefore, it is necessary to reduce the temperature rise of the common mode inductor on the electrolytic capacitor. One way is to increase the distance between the common mode inductor and the electrolytic capacitor, but this will cause the volume of the control circuit board to increase, and will make the distance between the EMC module and the switching power module larger, affecting the efficient operation of the switching power module. Another way is to reduce the temperature rise of the common-mode inductor, including setting a heat dissipation module to dissipate the heat of the common-mode inductor, or setting a multi-stage common-mode suppression module, that is, setting multiple common-mode inductors to bear the interference signal in stages, but this will increase the volume of the control circuit board, which does not meet the purpose of the thin and light setting of the food processor. And the multi-stage common-mode inductor will bear a larger proportion of the signal suppression effect at the first stage, so that the first stage will still generate more heat. On the basis of setting the EMC module, the present application further sets a magnetic ring on the connecting line between the DC brushless motor and the motor drive module. Since the magnetic ring directly acts on the DC brushless motor, the interference signal generated by the DC brushless motor is suppressed at the source. Since the magnetic ring is set externally, it does not need to be set on the control circuit board, and the area and volume of the control circuit board will not be increased. Instead, it is only necessary to install the magnetic ring in the main engine installation cavity. Figure 7 , 8 As shown in the figure, as a data comparison of not setting the magnetic ring and adding the magnetic ring, when the magnetic ring is not set, under the premise of not adding the multi-stage differential mode suppression module and the common mode suppression module, the food processing opportunity will have more interference signals leaking out and interfere with the external power grid; when the magnetic ring is added, under the same premise, the interference signal can be effectively suppressed to avoid the leakage of the interference signal and the interference to the external power grid. At the same time, such suppression also ensures that the common mode inductor will not be overheated, avoiding the impact on the electrolytic capacitor.

[0052] Furthermore, the food processor is further provided with a second magnetic ring 702, which is sleeved on the power line connected between the EMC module and the outside. In this way, the interference that may be generated by the food processor can be further filtered, and the reliability of the food processor can be improved. It can also avoid the influence of the internal components of the host on the power line of the host, so that the external interference of the food processor is reduced to a reasonable and controllable range.

[0053] It is understandable that when the host does not need to be thin and light, and the internal space of the host installation cavity is sufficient, three groups, four levels or other multi-level differential mode suppression modules and common mode suppression modules can also be set.

[0054] It can be understood that when the differential mode suppression module and the common mode suppression module are arranged in multiple stages, a plurality of common mode inductors may be arranged accordingly.

[0055] It can be understood that the control circuit board can also be set to other shapes; the EMC module can also be set on the side or in the middle according to the connection relationship with the outside.

[0056] 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 food processing machine with reliable operation, comprising a main machine and a processing module, wherein the main machine comprises a housing, a DC brushless motor and a control circuit board, wherein a main machine installation cavity is formed inside the housing, and the DC brushless motor and the control circuit board are arranged in the main machine installation cavity, characterized in that: The brushless DC motor includes a working process with a rotation speed of 300 to 5000 rpm; The control circuit board includes an EMC module, a switching power supply module and a motor drive module, wherein the EMC module is connected between an external power supply and the switching power supply module and the motor drive module, wherein the EMC module includes a differential mode suppression module and a common mode suppression module, wherein the common mode suppression module includes a common mode inductor, and the switching power supply module includes an electrolytic capacitor, wherein the electrolytic capacitor is arranged within a 4 cm range of the common mode inductor; A magnetic ring is also provided in the host installation cavity, and the magnetic ring is sleeved on the connection line connecting the DC brushless motor and the motor drive module.

2. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The differential mode suppression module and the common mode suppression module are respectively configured to be no more than two stages.

3. A food processing machine with reliable operation as claimed in claim 2, characterized in that: The differential mode suppression module includes a primary differential mode suppression module and a secondary differential mode suppression module, the common mode suppression module is set as a primary level, and the common mode suppression module is set between the primary differential mode suppression module and the secondary differential mode suppression module.

4. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The number of the common-mode inductor is 1, the common-mode inductor is adjacent to the switching power supply module, and the switching power supply module includes at least 2 electrolytic capacitors located within 4 cm of the common-mode inductor.

5. A food processing machine with reliable operation as claimed in claim 4, characterized in that: The control circuit board is arranged in a square shape, the EMC module is arranged at one corner of the control circuit board, the EMC module is provided with a connection portion connected to an external power supply, the switching power supply module is arranged in an area adjacent to the EMC module, and the common mode inductor and the electrolytic capacitor are located on the same side of the control circuit board.

6. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The connecting wires of the brushless DC motor are three-phase wires U, V and W, which are wound into the magnetic ring in the same direction and with the same number of turns.

7. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The magnetic ring is a hollow cylinder made of magnetic material, and the outer diameter of the magnetic ring is no more than 2 cm.

8. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The inductance of the common mode inductor is not greater than 10mH.

9. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The processing module includes a heating element, the power of the brushless DC motor is not greater than 1000W, the power of the heating element is not greater than 1000W, the differential mode suppression module includes an X capacitor, and the capacitance of the X capacitor is 0.22uF-2uF.

10. A food processing machine with reliable operation as claimed in claim 1, characterized in that: The food processor further comprises a second magnetic ring, wherein the second magnetic ring is sleeved on a power line connected between the EMC module and the outside.

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