PORTABLE FAN, DRIVE CIRCUIT, HANDHELD FAN, AND NECK FAN

A portable fan includes: a fan and a power supply drive assembly electrically connected to the fan. The power supply drive assembly comprises a battery and a fan drive circuit electrically connected to the battery. The fan drive circuit includes a master control circuit; a three-phase drive circuit; and an inverted-phase electric potential detection circuit. The battery is configured to supply power to the fan drive circuit.

TECHNICAL FIELD

The present disclosure relates to the field of fans, and in particular to a portable fan, drive circuit, handheld fan, and neck fan.

BACKGROUND

Fans are very commonly-used domestic appliances in daily lives and can drive air to flow for cooling. Portable fans currently in the art has a light weight and can be easily carried and are popular among people. However, for the portable fan in the art, due to having a small size and a light weight, an airflow speed generated by the fan may be low, and after a long-term use, heat is generated, which may lead to an explosion.

SUMMARY OF THE DISCLOSURE

The present disclose provides a portable fan, including a fan and a power supply drive assembly electrically connected to the fan; wherein the power supply drive assembly comprises a battery and a fan drive circuit electrically connected to the battery. The fan drive circuit includes: a master control circuit; a three-phase drive circuit, comprising at least three signal input ends and three drive signal output ends; wherein each of the at least three signal input ends is electrically connected to the master control circuit to receive control signals; each of the three drive signal output ends is electrically connect to a respective one of three signal ends of a direct-current (DC) brushless fan motor to respectively output a three-phase drive signal to drive the DC brushless fan motor to rotate; and an inverted-phase electric potential detection circuit, comprising three detection branches; wherein each of the three detection branches comprises a detection end and a detection output end electrically connected to the detection end; three detection ends of the three detection branches are respectively electrically connected to the three drive signal output ends; three detection output ends of the three detection branches are electrically connected to the master control circuit to respectively output a first detection signal, a second detection signal, and a third detection signal; the master control circuit is informed of a phase of the three-phase drive signal based on the first detection signal, the second detection signal, and the third detection signal to adjust the control signals. The battery is configured to supply power to the fan drive circuit.

The present disclosure further provides a fan, including: a neck housing, defining a neck space, wherein the neck housing is configured to be worn to a neck of a user, and the neck is configured to be received in the neck space; an airflow portion, arranged inside the neck housing and configured to blow an airflow towards the neck space; wherein the airflow portion comprises rotation air blades and a three-phase motor drive assembly driveably connected to the rotation air blades to drive the rotation air blades to rotate to generate the airflow.

The present disclosure further provides a fan, including: an air duct portion, including a body portion, wherein the body portion defines an air guiding cavity therein; the air duct portion defines an air outlet and an air inlet respectively at opposite ends thereof; the air outlet and the air inlet are communicated to the air guiding cavity, and a positioning protruding post is arranged inside the body portion; an airflow portion, comprising rotation air blades and a drive portion that is driveably connected to the rotation air blades, wherein the rotation air blades are rotatably received in the air guiding cavity and are arranged facing towards the air outlet; the drive portion comprises a stator and a rotor sleeving an outside of the stator; the rotor is fixedly mounted on the rotation air blades and is coaxially arranged with the rotation air blades; the stator fixedly sleeves the positioning protruding post; the drive portion is a three-phase motor; a handheld portion, connected to the air duct portion, wherein the handheld portion defines a mounting cavity; a power supply assembly is received in the mounting cavity; and the power supply assembly is electrically connected to the three-phase motor.

DETAILED DESCRIPTION

In order to facilitate better understanding of purposes, structures, features and efficacies of the present disclosure, a portable fan of the present disclosure will be further described by referring to the accompanying drawings and specific embodiments.

Technical solutions in the embodiments of the present disclosure will be clearly and completely described below by referring to the accompanying drawings in the embodiments of the present disclosure. It is to be understood that the specific embodiments described herein are for the purpose of explaining the present disclosure only, and do not limit the present disclosure. It is also to be noted that, for the purpose of description, only partial structures related to the present disclosure, instead of all structures, are shown in the accompanying drawings. Based on the embodiments of the present disclosure, all other embodiments obtained by any ordinary skilled person in the art without creative work shall fall within the scope of the present disclosure.

The terms “first”, “second”, and so on, in the present disclosure are used to distinguish between different objects and are not used to describe a particular order. In addition, the terms “includes”, “have”, and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, a method, a system, a product, or an apparatus including a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units that are not listed or include steps or units that are inherently included in the process, the method, the system, the product, or the apparatus.

Reference to “embodiments” herein means that particular features, structures, or characteristics described in one embodiment may be included in at least one embodiment of the present disclosure. The presence of the phrase at various sections in the specification does not necessarily refer to one same embodiment or to a separate or alternative embodiment that is exclusive of other embodiments. It is understood by any ordinary skilled person in the art, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.

It should be noted that when an element is described as being “fixed to” or “arranged” on another element, the element may be directly or indirectly on the another element. When an element is described as being “connected” to another element, the element may be directly or indirectly connected to the another element. The embodiments and features of the embodiments in the present disclosure may be combined with each other without conflict. The present disclosure will be described in detail below by referring to the accompanying drawings and the embodiments.

It is to understand that the terms “length”, “width”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside” and the like indicate orientations or positional relationships based on those shown in the accompanying drawings, and are used to facilitate and simplify description of the present disclosure. The terms are not intended to indicate or imply that a device or an element must have a specific orientation or must be constructed and operated in a specific orientation. Therefore, the terms shall not be interpreted as a limitation of the present disclosure.

Furthermore, the terms “first” and “second” are used only for descriptive purposes, and shall not be interpreted as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined by “first” and “second” may expressly or implicitly include one or more such features. In the description of this application, “a plurality of” means two or more, unless otherwise expressly and specifically limited.

A technical solution1is shown inFIGS.1to24.

As shown inFIGS.1to3, the present embodiment provides a drive circuit for a portable fan. The fan drive circuit of the portable fan is applicable for various types of fans. Specifically, the drive circuit for the portable fan includes: a master control circuit11, a three-phase drive circuit12, and an inverted-phase electric potential detection circuit14.

The three-phase drive circuit12includes at least three signal input ends121and three drive signal output ends122. Each of the at least three signal input ends121is electrically connected to the master control circuit11to receive control signals. The three drive signal output ends122are electrically connect to three signal ends (U, V, and W) of a direct-current (DC) brushless fan motor to output a three-phase drive signal to drive the DC brushless fan motor to rotate. The inverted-phase electric potential detection circuit14includes three detection branches141. Each detection branch141includes a detection end1411and a detection output end1412electrically connected to the detection end. Three detection ends1411of the three detection branches141are respectively electrically connected to the three drive signal output ends122. Three detection output ends1412of the three detection branches141are electrically connected to the master control circuit11to respectively output a first detection signal, a second detection signal, and a third detection signal. In this way, the master control circuit11is informed of a phase of the three-phase drive signal based on the first detection signal, the second detection signal, and the third detection signal to adjust the control signals.

As shown inFIG.3, the detection branch141includes a first detection resistor R1, a second detection resistor R2, and a third detection resistor R3. The first detection resistor R1 and the second detection resistor are connected to each other in series. An end of the first detection resistor R1 away from the second detection resistor R2 is the detection end1411, and an end of the second detection resistor R2 away from the first detection resistor R1 is grounded. A node between the first detection resistor R1 and the second detection resistor R2 is the detection output end1412.

By arranging the three-phase drive circuit12, energy-saving performance and control performance of the fan motor are improved, and a service life of the fan drive circuit and the portable fan is extended. By arranging the inverted-phase electric potential detection circuit14, the master control circuit11may be easily informed of the phase of the DC brushless fan motor, such that the master control circuit11may send corresponding control signals to the three-phase drive circuit12to control driving of the DC brushless fan motor, and reliability and stability of the driving is improved.

As shown inFIG.2, the three-phase drive circuit12includes a first transistor Q1, a second transistor Q2, a third transistor Q3, a fourth transistor Q4, a fifth transistor Q5, a sixth transistor Q6, a seventh transistor Q7, an eighth transistor Q8, and a ninth transistor Q9. A first conductive end1211of the first transistor Q1, a first conductive end1211of the second transistor Q2, and a first conductive end1211of the third transistor Q3 are connected to a power supply end1212. A first conductive end1211of the fourth transistor Q4 is connected to the power supply end1212. A first conductive end1211of the fifth transistor Q5 is connected to the power supply end1212. A first conduction end1211of the sixth transistor Q6 is connected to the power supply end1212. A control end of the fourth transistor Q4, a control end of the fifth transistor Q5, and a control end of the sixth transistor Q6 are electrically connected to the master control circuit11. A control end of the seventh transistor Q7 is electrically connected to the control end of the fourth transistor Q4, a control end of the eighth transistor Q8 is electrically connected to the control end of the fifth transistor Q5, and a control end of the ninth transistor Q9 is electrically connected to the control end of the sixth transistor Q6, such that the control signals are received. Second conduction ends1213of the fourth transistor Q4, the fifth transistor Q5, and the sixth transistor Q6 are grounded. A first conductive end1211of the seventh transistor Q7 is connected to a second conductive end1213of the first transistor Q1. A second conductive end1213of the seventh transistor Q7 is grounded. A first conductive end1211of the eighth transistor Q8 is connected to a second conductive end1213of the second transistor Q2. A second conductive end1213of the eighth transistor Q8 is grounded. A first conductive end1211of the ninth transistor Q9 is connected to the second conductive end1213of the third transistor Q3. A second conductive end1213of the ninth transistor Q9 is grounded. A node between the first conductive1211of the seventh transistor Q7 and the second conductive1213of the first transistor Q1, a node between the first conductive1211of the eighth transistor Q8 and the second conductive1213of the second transistor Q2, and a node between the first conductive1211of the ninth transistor Q9 and the second conductive1213of the third transistor Q3 respectively serve as the three drive signal output ends122. The at least three signal input ends121are three PWM signal input ends. The control signals include three PWM signals.

As shown inFIG.2, the fan drive circuit further includes a current detection circuit15. The second conductive ends1213of the seventh transistor Q7, the eighth transistor Q8, and the ninth transistor Q9 are all grounded via the current detection circuit15. The current detection circuit15is electrically connected to the master control circuit11. The current detection circuit15includes a sense resistor151and a sense capacitor152. The second conductive ends1213of the seventh transistor Q7, the eighth transistor Q8, and the ninth transistor Q9 are grounded via the sense resistor151and the sense capacitor152sequentially. A node between the sense resistor151and the sense capacitor152is electrically connected to the master control circuit11. By arranging the current detection circuit15, when a current is abnormal, the master control circuit11may control the fan drive circuit to stop operating or to operate at a lower power, such that an overcurrent protection is provided for the fan drive circuit, and reliability and the service life of the fan drive circuit are improved.

As shown inFIGS.4and6, the fan drive circuit further includes an interface circuit16and a charge management circuit17. The interface circuit16is configured to be electrically connected to an external power source to receive an external voltage. The charge management circuit17is electrically connected between the interface circuit16and a battery VBAT to receive the external voltage and to charge or output a power supply voltage to the battery VBAT. The fan drive circuit further includes a keypad31. An end of the keypad31is connected to the master control circuit11, and the other end of the keypad31is grounded. The fan drive circuit further includes an indicator branch19. The indicator branch19includes a light-emitting diode and a resistor that is connected in series to the light-emitting diode. A positive electrode of the light-emitting diode is electrically connected to the master control circuit11, and a negative electrode of the light-emitting diode is grounded.

Specifically, in the present embodiment, the fan drive circuit may be arranged for a neck fan and a handheld fan, but is not limited to the neck fan and the handheld fan, the fan drive circuit may further be applied to other portable fans such as desktop table fans, floor fans, clip fans, folding fans, and the like. Two DC brushless fan motors are respectively arranged in a left side and a right side of the neck fan and are configured to respectively drive fan blades in the left side and fan blades in the right side of the neck fan to rotate.

As shown inFIGS.1,2, and5, the master control circuit11includes a master control chip111and an auxiliary chip113. The master control circuit11includes the master control chip111and the auxiliary chip113. Two three-phase drive circuits12, two inverted-phase electric potential detection circuits14, and two DC brushless fan motors are arranged in one-to-one correspondence to each other. The master control chip111is electrically connected to one of the two three-phase drive circuits12to output the control signals to one of the two three-phase drive circuits12to drive the respective one of the two brushless DC fan motors. The inverted-phase electric potential detection circuit14is electrically connected to one three-phase drive circuit12and outputs the first detection signal, the second detection signal, and the third detection signal to the master control chip111. In this way, the master control chip111is informed of the phase of the three-phase drive signal of the one three-phase drive circuit12to adjust the control signals output to the one three-phase drive circuit12. The auxiliary chip113is electrically connected to the other three-phase drive circuit12to output the control signals to the other three-phase drive circuit12to drive the other one of the two DC brushless fan motors. The other inverted-phase electric potential detection circuit14is electrically connected to the respective one three-phase drive circuit12and outputs a corresponding first detection signal, a corresponding second detection signal and a corresponding third detection signal to the auxiliary chip113. In this way, the auxiliary chip113is informed of the phase of the three-phase drive signal of the other three-phase drive circuit12to adjust the control signals output to the other three-phase drive circuit12.

In this embodiment, the master control chip111, the corresponding three-phase drive circuit12, and the corresponding inverted-phase electric potential detection circuit14are arranged on one module (such as on a first circuit board) and may be arranged on a same side of the neck fan as the corresponding DC brushless fan motor. The auxiliary chip113, the corresponding three-phase drive circuit12, and the corresponding inverted-phase electric potential detection circuit14are arranged on another one module (such as on a second circuit board that is independent from the first circuit board) and may be arranged on the other side of the neck fan, together with the corresponding DC brushless fan motor. It is understood that the above configuration has better rationality and compactness, and reliability of connection and driving is improved. However, arrangement of the three-phase drive circuit12, the inverted-phase electric potential detection circuit14, the master control chip111, and the auxiliary chip113may be arranged in various manners. For example, the three-phase drive circuit12, the inverted-phase electric potential detection circuit14, the master control chip111, and the auxiliary chip113are arranged on a same circuit board; alternatively, the three-phase drive circuit12and the inverted-phase electric potential detection circuit14are arranged on one circuit board, and the master control chip111and the auxiliary chip113are arranged on another one circuit board. The arrangement may be determined according to the actual demands, which will not described here.

As shown inFIGS.7and8, the fan drive circuit further includes a first connector261and a speed adjustment interface circuit26having a second connector262. A first pin and a second pin of the first connector261are electrically connected to the master control chip111. A third pin of the first connector261is grounded. A first pin of the second connector262is connected to the battery VBAT via a first connection resistor and is also connected to the auxiliary chip113via a second connection resistor. A second pin of the second connector262is connected to the auxiliary chip113via a third connection resistor, and a third pin of the second connector262is grounded. In addition, each pin of the first connector261and the second connector262may be electrically connected to each other in one-to-one correspondence with each other. In this way, rotation speeds of the two DC brushless fan motors may be synchronously adjusted.

As shown inFIGS.9to14, the fan drive circuit of a second embodiment is shown. Portions of the fan drive circuit of the present embodiment are the same as those in the first embodiment and will not be repeated. Portions of the fan drive circuit of the present embodiment that are different from those in the first embodiment will be described in the following. Firstly, the master control circuit11of the present embodiment is different from that of the first embodiment, and the master control circuit11of the present embodiment may substantially include the master control chip111.

As shown inFIG.10, in the present embodiment, the three-phase drive circuit12includes a first transistor Q1, a second transistor Q2, a third transistor Q3, a fourth transistor Q4, a fifth transistor Q5, and a sixth transistor Q6. A first conductive end1211of the first transistor Q1, a first conductive end1211of the second transistor Q2, and a first conductive end1211of the third transistor Q3 are connected to a power supply end1212. A first conductive end1211of the fourth transistor Q4 is connected to a second conductive end1213of the first transistor Q1. A first conductive end1211of the fifth transistor Q5 is connected to a second conductive end1213of the second transistor Q2. A first conduction end1211of the sixth transistor Q6 is connected to a second conductive end1213of the third transistor Q3. A node between the first conductive1211of the fourth transistor Q4 and the second conductive1213of the first transistor Q1, a node between the first conductive1211of the fifth transistor Q5 and the second conductive1213of the second transistor Q2, and a node between the first conductive1211of the sixth transistor Q6 and the second conductive1213of the third transistor Q3 respectively serve as the three drive signal output ends122. Control ends of the first transistor Q1, the second transistor Q2, the third transistor Q3, the fourth transistor Q4, the fifth transistor Q5, and the sixth transistor Q6 are electrically connected to the master control circuit11to receive the control signals; and the control signals include six PWM signals.

As shown inFIG.10, substantially the same as the first embodiment, the second conductive end1213of the sixth transistor Q6 is grounded via the current detection circuit15, and the current detection circuit15is electrically connected to the master control circuit11. The current detection circuit15includes a sense resistor151and a sense capacitor152. The second conductive end1213of the sixth transistor Q6 is grounded via the sense resistor151. The sense capacitor152is connected in parallel with the sense resistor151. A node between the sense resistor151and the second conduction end1213of the sixth transistor Q6 is electrically connected to the master control circuit11. The current detection circuit15further includes a first series resistor153, a second series resistor154, a parallel resistor155. The parallel resistor155is connected in parallel with the sense resistor151. The first series resistance153is connected between an end of the sense capacitor152and an end of the sense resistor151. The second series resistance154is connected between the other end of the sense capacitor152and the other end of the sense resistor151. By arranging the current detection circuit15, when the current is abnormal, the master control circuit11may control the fan drive circuit to stop operating or to operate at a lower power, such that an overcurrent protection is provided for the fan drive circuit, and reliability and the service life of the fan drive circuit are improved.

As shown inFIG.11, the inverted-phase electric potential detection circuit14of the second embodiment is substantially the same as that of the first embodiment, and will not be repeated herein.

As shown inFIG.12, the fan drive circuit further includes a transistor temperature detection circuit24. The transistor temperature detection circuit24may be disposed adjacent to each transistor of the three-phase drive circuit12and includes a first voltage divider resistor241and a thermistor242connected in series with the first voltage divider resistor241. The thermistor242is configured to sense a temperature of each transistor of the three-phase drive circuit12. A node between the first voltage divider resistor241and the thermistor242is electrically connected to the master control circuit11and is configured to output a temperature signal, enabling the master control circuit11to control, based on the temperature signal, the fan drive circuit to enter or not enter a temperature protection state. The thermistor242is connected between the first voltage divider resistor241and the ground. The transistor temperature detection circuit24further includes a voltage regulated capacitor243connected in parallel with the thermistor242. By arranging the transistor temperature detection circuit24, the master control circuit11may be informed whether the temperature of each transistor of the three-phase drive circuit12is abnormal and may control the fan drive circuit to stop operating or to operate at a lower power when the temperature is abnormal. In this way, an over-temperature protection is provided for the fan drive circuit, and reliability and the service life of the fan drive circuit are improved.

As shown inFIG.13, the fan drive circuit further includes a battery voltage detection circuit25that is electrically connected between the positive electrode of the battery VBAT and the ground. An output end of the battery voltage detection circuit25is electrically connected to the master control circuit11. By arranging the battery voltage detection circuit25, the master control circuit11may be informed whether a battery voltage is normal or not. When the battery voltage is abnormal, the master control circuit11may control the fan drive circuit to stop operating or to operate at a lower power. Therefore, reliability and the service life of the fan drive circuit are improved.

Specifically, the battery voltage detection circuit25includes a second voltage divider resistor251and a third voltage divider resistor252that is connected in series to the second voltage divider resistor251. A node between the second voltage divider resistor251and the third voltage divider resistor252is electrically connected to the master control circuit11. It is understood that the above-described battery voltage detection circuit25is simple in structure and has high reliability and a low cost.

As shown inFIG.14, the fan drive circuit of the second implementation further includes a burner interface28to burn in a control program to the master control circuit11. The burner interface28may be a SWD burner interface, but is not limited to the above.

As shown inFIGS.15to16, the fan drive circuit of a third embodiment is provided. Portions of the fan drive circuit of the present embodiment are the same as those in the second embodiment and will not be repeated. Portions of the fan drive circuit of the present embodiment that are different from those in the second embodiment will be described in the following.

As shown inFIG.16toFIG.17, the three-phase drive circuit12of the third embodiment is essentially the same as the three-phase drive circuit12of the second embodiment. The master control circuit11of the third embodiment is different from that of the second embodiment. In the present embodiment, the master control circuit11includes a master control chip111and three three-phase control chips112. Each of the three three-phase control chips112is electrically connected to the master control chip111and the three-phase drive circuit12.

As shown inFIGS.16and18, the fan drive circuit further includes a filter capacitor253and a sampling resistor254connected in series to the filter capacitor253. The sampling resistor254is connected between the filter capacitor253and the ground. A node between the filter capacitor253and the sampling resistor254is electrically connected to the master control circuit11. Further, the fan drive circuit further includes a signal amplification circuit29. An input end of the signal amplification circuit29is connected to the node between the filter capacitor253and the sampling resistor254. The signal amplification circuit29is configured to amplify a signal sampled by the sampling resistor254(i.e., a signal of the node between the filter capacitor253and the sampling resistor254) and to provide the amplified signal to the master control circuit11. In this way, the main control circuit11of the fan drive circuit may keenly detect an abnormal voltage or current signal when the fan drive circuit is abnormal and then perform protection against the abnormalities, such as stopping operating or reducing a fan speed. In this way, safety of using the fan drive circuit is improved.

As shown inFIG.19, the transistor temperature detection circuit24of the third embodiment is essentially the same as that of the second embodiment and will not be repeated herein.

As shown inFIG.20, a schematic view of a light control circuit30of the fan drive circuit in the third embodiment is provided. The light control circuit30includes a light-emitting element301and a control switch302. A positive electrode of the light-emitting element301receives a drive voltage. A negative electrode of the light-emitting element301is grounded via two conductive ends of the resistor and the control switch302. A control end of the control switch302is electrically connected to the master control circuit11, such that the master control circuit11outputs a light control signal to the control end of the control switch302to control the light-emitting element301to emit light.

As shown inFIG.21, the fan drive circuit further includes a Hall detection circuit23. The Hall detection circuit23is electrically connected to the master control circuit11to detect a magnetic field generated by the DC brushless fan motor and to output a Hall detection signal to the master control circuit11. In this way, the master control circuit11may be informed, based on the Hall detection signal, of a position of a rotor of the DC brushless fan motor, such that the master control circuit11may provide a corresponding control signal to control the DC brushless fan motor to operate. In this case, a start-up time length of the fan using the fan drive circuit is shorter, and the fan may not shake during starting-up, and a better user experience is provided.

As shown inFIG.21, the Hall detection circuit23further includes a motor temperature detection element232connected between a Hall element231of the Hall detection circuit23and the master control circuit11. The motor temperature detection element232may be a sampling resistor. By arranging the motor temperature detection element232, the master control circuit11may be informed of whether a temperature of the DC brushless fan motor is abnormal. When the temperature of the DC brushless fan motor is abnormal, the master control circuit11may control the fan drive circuit to stop operating or operate at a lower power, such that an over-temperature protection is provided for the fan drive circuit, and reliability and the service life of the fan drive circuit are improved.

As shown inFIGS.17and22, the fan drive circuit further includes a voltage conversion circuit20. The voltage conversion circuit20is configured to receive a battery voltage (VB+), convert the battery voltage into a drive voltage (such as 15V), and provide the drive voltage to power supply ends of the three three-phase control chips112. The master control chip111is configured to output a master control signal to the three three-phase control chips112, such that each of the three three-phase control chips112outputs the respective control signal to the three-phase drive circuit12.

The fan drive circuit further includes a switch control circuit21. The switch control circuit21is electrically connected to the battery VBAT, the voltage conversion circuit20, and the master control circuit11to control operation of the voltage conversion circuit20. The switch control circuit21includes a keypad211, a first switch transistor212, a second switch transistor213, and a third switch transistor214. Two conductive ends of the first switch transistor212are respectively connected to the positive electrode of the battery VBAT and the input end of the voltage conversion circuit20. A control end of the first switch transistor212is grounded via two conductive ends of the third switch transistor214. The positive electrode of the battery VBAT is connected to the control end of the third switch transistor214via the two conductive ends of the first switch transistor212and a one-way diode215. A control end of the second switch transistor213is grounded via the keypad211. A control end of the third switch transistor214is electrically connected to the master control circuit11. A node between the second switch transistor213and the one-way diode215is further electrically connected to a switch signal end of the master control circuit11.

When the keypad211is pressed to be conductive, the second switch transistor213is turned on, the third switch transistor214is turned on, and the node between the second switch transistor213and the one-way diode215outputs a first switching signal (ON) to the switch signal end of the master control circuit11. The first switch transistor212is turned on to enable the battery voltage of the battery VBAT to be supplied to the voltage conversion circuit20. When the pressing on the keypad211is released, the second switch transistor213is turned off, the master control circuit11maintains the third switch transistor214to be turned on based on a power supply turn-on signal being output from the first switching signal to the control end of the third switch transistor214, and the battery voltage of the battery VBAT is supplied to the voltage conversion circuit20.

Further, when the battery voltage of the battery VBAT is supplied to the voltage conversion circuit20, and when the keypad211is again pressed to be conductive, the node between the second switch transistor213and the one-way diode215outputs a second switching signal (OFF) to the switch signal end of the master control circuit11, the master control circuit11controls the third switch transistor214to be turned off based on a power supply turn-off signal being output from the second switching signal to the control end of the third switch transistor214. In this way, the first switch transistor212is turned off, the battery voltage of the battery VBAT cannot be supplied to the voltage conversion circuit20until the keypad211is again pressed.

The keypad211, the first switch transistor212, the second switch transistor213and the third switch transistor214operate together with the master control circuit11to control whether the battery voltage of the battery VBAT is supplied to the voltage conversion circuit20. In this way, a simple control logic is provided, and the circuit has higher reliability.

As shown inFIG.23, the fan drive circuit further includes a DC conversion circuit22. The DC conversion circuit22is configured to receive the drive voltage (such as a DC voltage of 15V) and convert the drive voltage to other DC operating voltages, such as a DC operating voltage of 3.3V and 5V.

As shown inFIG.24, the present disclosure further provides a portable fan2. The portable fan2includes a fan drive circuit3, a DC brushless fan motor4, and fan blades5driven by the DC brushless fan motor. The fan drive circuit3may be arranged with the fan drive circuit as described in any of the above embodiments.

For the fan drive circuit and the portable fan2in the present embodiment, the master control circuit11, the three-phase drive circuit12, the inverted-phase electric potential detection circuit14, and the DC brushless fan motor are arranged. The energy-saving performance and control performance of the fan motor are improved, such that reliability of the fan drive circuit and the fan2are improved. In addition, the service life of the fan drive circuit and the fan2is extended, the arrangement of the DC brushless fan motor allows the fan2to have a more compact and smaller configuration, and the fan2has increased competitiveness in the market.

A technical solution2is shown inFIGS.25to30.

As shown inFIG.25andFIG.26, a partial schematic view and a partial circuit diagram of the portable fan100of a first implementation are shown, where the partial schematic view and the partial circuit diagram are simplified. For example, a drive circuit between the control main board2and the fan assembly6is omitted. A battery protection device3usually includes pins B+, B−, P+ and P−. The battery protection device3usually includes an intelligent processor31, a current collection module32and a voltage collection module33. The intelligent processor31is connected to the current collection module32and the voltage collection module33. The intelligent processor31may be an IC control chip, or other types of chips that are not limited herein. The voltage collection module33operates as follows. The pins B+ and B− of the battery protection device3are respectively connected to a positive electrode and a negative electrode of a lithium ion battery1. In this way, the battery protection device3monitors a voltage between the positive electrode and the negative electrode of the lithium ion battery1. The current collection module32operates as follows. A MOS1 and a MOS2 are connected to each other in series on a circuit, such that the MOS1 and the MOS2 monitor a current of the circuit.

The intelligent processor31monitors, by the voltage collection module33and the current collection module32, the voltage of the lithium ion battery1and the current of the circuit to control the MOS1 and the MOS2 to be on or off. The MOS1 and the MOS2 serve as switches in the circuit to respectively control a charging circuit and a discharging circuit to be conducted or disconnected. During normal operation, when the voltage of the lithium ion battery1is within a range of A to B, both the MOS1 and the MOS2 are in an on state. When the intelligent processor31determines, based on a monitoring result of the voltage collection module33, that the voltage of the lithium ion battery1reaches a value of B, the intelligent processor31controls the MOS1 (the charging circuit) to be off, such that the charging circuit is disconnected, and an external power source cannot charge the lithium ion battery1. In this way, an overcharging protection is provided. When the intelligent processor31determines, based on the monitoring result of the voltage collection module33, that the voltage of the lithium ion battery1is lower than a value of A, the intelligent processor31controls the MOS2 (the discharging circuit) to be off, such that the discharging circuit is disconnected, and the lithium ion battery1is not discharged to any load. In this way, a discharging protection is provided. During the lithium ion battery1being normally discharged to a load, a discharge current passes through the MOS1 and the MOS2 that are connected to each other in series. Due to a conduction impedance of the MOS1 and the MOS2, a voltage is generated at two ends of the MOS1 and the MOS2, and the intelligent processor31detects a value of the generated voltage. When the load is abnormal due to some reasons, resulting in the current of the circuit being increased, and when the current of the circuit is increased to enable the voltage between the ends of the MOS1 and the MOS2 to be greater than a value of C, the intelligent processor31controls the MOS1 and the MOS2 to be off, such that the discharging circuit is disconnected, the current of the circuit is turned to zero, and therefore, an overcurrent protection is provided. During the lithium ion battery1being discharged to the load, when the current of the circuit is increased to enable the voltage between the ends of the MOS1 and the MOS2 to be greater than a value of D (D>C), the intelligent processor31determines that the load is short-circuited and controls the MOS2 (the discharging circuit) to be off, such that the discharging is disconnected, and therefore, a short-circuit protection is provided. The current collection module32and the voltage collection module33are both connected to the lithium ion battery1to monitor the current and the voltage of the lithium ion battery1. Since the intelligent processor31, the current collection module32, and the voltage collection module33operate together, the lithium ion battery1is prevented from overvoltage, undervoltage, overcurrent, and short circuits, such that an operation state of the lithium ion battery1is intelligently controlled.

The battery protection device3is arranged on the control main board2. Therefore, when the lithium ion battery1needs to be disassembled, the lithium ion battery1can be directly removed from the portable fan100, and another lithium ion battery1may be reassembled or replaced. In this way, disassembling and assembling of the battery protection device3with the lithium ion battery1can be reduced, facilitating inspection and replacement of the lithium ion battery1.

As shown inFIGS.25to26, the control main board2is arranged with a power supply module4. The pins P− and P+ of the battery protection device3are respectively connected to pins of the power supply module4, such that the current collection module32and the voltage collection module33are connected to the power supply module4to monitor a current and a voltage of the power supply module4. Specifically, the power supply module4includes a charging interface41, and in the present embodiment, the charging interface41is a TYPE-C female port. Of course, in other embodiments, the charging interface41may be a port in other connection types. During charging, pins VBUS and GND are respectively connected to the pins P− and P+ of the battery protection device3, a conducted TYPE-C male terminal is inserted into the charging interface41to allow the charging interface41to intake power from an external power source. The charging interface41supplies power to the battery protection device3via the pins VBUS and GND, and the battery protection device3, after being supplied with the power, charges power to the lithium ion battery via the pins B− and B+. During discharging, the lithium-ion battery1, after being charged, supplies power to the control board2through the pins P− and P+ of the battery protection device3. Therefore, a wire, which is connected between the lithium ion battery1and the control main board2for power supplying, can be eliminated. In this way, a circuit configuration of the portable fan100is simplified. The control main board2is further arranged with a switch7and a motor (not shown, the same hereinafter). The switch7is exposed outwardly to be operated by the user. Only when the switch7is turned on, the lithium ion battery1can supply power to the motor of the control main board2. The motor drives the fan assembly6to rotate to activate the portable fan100, otherwise, the portable fan100cannot be activated.

As shown inFIG.27andFIG.28, wires between various components are also omitted inFIG.28. The portable fan100is arranged with a housing5, a fan assembly6arranged inside the housing5, the lithium-ion battery1arranged inside the housing5, the control main board2arranged inside the housing5, and the battery protection device3arranged inside the housing5. The housing5is arranged with an air inlet portion61and an air outlet portion62. The housing5includes a first housing51and a second housing52mated with the first housing51. The lithium ion battery1is configured to supply power to the portable fan100. The fan assembly6rotates to intake air from the air inlet portion61and drives the air to be output from the air outlet portion62. The control main board2is configured to control the portable fan100. The battery protection device3is configured to protect the lithium ion battery1. Further, the power supply module4is not shown inFIG.28. It is to be understood that the power supply module4may also be arranged on the control main board2. Other structures and functions of the present embodiment are the same as those in the first embodiment and will not be repeated herein.

Of course, the portable fan100is not limited to a portable fan, and the portable fans100applicable in other application scenarios fall within the scope of the present disclosure.

In summary, the portable fan100herein has the following beneficial effects:

The battery protection device3is arranged on the control main board2, such that the lithium ion battery1can be directly removed from the portable fan100when the lithium ion battery1needs to be disassembled, and then another lithium ion battery1can be reassembled or replaced. Disassembling and assembling of the battery protection device3with the lithium ion battery1can be reduced, facilitating inspection and replacement of the lithium ion battery1.

When the battery protection device3is electrically connected to the control main board2, the battery protection device3may be integrated in the control main board2, the wire between the battery protection device3and the control main board2can be eliminated, and space utilization is improved.

After charging, the lithium ion battery1supplies power to the control main board2through the pins P− and P+ of the battery protection device3. Any wire, which is connected between the lithium ion battery1and the control main board2for power supplying, can be eliminated. In this way, a circuit configuration of the portable fan100is simplified.

A technical solution4is shown inFIGS.41to47.

As shown inFIG.41toFIGS.47, in order to solve the above problem, the present disclosure provides a portable fan, including: an air duct portion10, an airflow portion20, a handheld portion30. The air duct portion10includes a body portion, the body portion defines an air guiding cavity13. The air duct portion10defines an air outlet121and an air inlet111respectively at two opposite ends thereof. The air outlet121and the air inlet111are both communicated to the air guiding cavity13. A positioning protruding post122is arranged inside the body portion. The airflow portion includes rotation air blades21and a drive portion22that is drivably connected to the rotation air blades21. The rotation air blades21are rotatably received in the air guiding cavity13and are arranged facing towards the air outlet121. The drive portion22includes a stator221and a rotor222sleeving an outside of the stator221. The rotor222is fixedly mounted on the rotation air blades21and is coaxially arranged with the rotation air blades21. The stator221fixedly sleeves the positioning protruding post122. The handheld portion30is connected to the air duct portion10. The handheld portion30defines a mounting cavity34. A power supply assembly31is received in the mounting cavity34. The power supply assembly31is electrically connected to the drive portion22. For the portable fan in the present embodiment, the drive portion22, which is driveably connected to the rotation air blades21, is configured as the stator221and the rotor222sleeving the outside of the stator221. The rotor222is fixedly mounted on the rotation air blades21and is coaxially arranged with the rotation air blades21. In addition, the stator221fixedly sleeves the positioning protruding post122. In this way, a driving force generated by the drive portion22can be directly transmitted to the rotation air blades21through the rotor222, a transmission member between the drive portion22and the rotation air blades21can be omitted. a transmission efficiency of the portable fan is improved. In an embodiment, the power supply assembly31is a storage battery.

As shown inFIGS.1and5, in an embodiment, the body portion includes a first housing11and a second housing12connected to the first housing11. The air guiding cavity13is formed between the first housing11and the second housing12. The first housing11defines the air inlet111, the second housing12defines the air outlet121. The positioning protruding post122is arranged on the second housing12and extends along an extension direction of the air guiding cavity13.

As shown inFIGS.4to7, in an embodiment, the rotation air blades21defines a fixation hole, an axis of the fixation hole coincides with an axis of the rotation air blades21. The airflow portion20further includes a rotation shaft23. A first end of the rotation shaft23is fixedly received in the fixation hole. A positioning hole1221is defined inside the positioning protruding post122. An axis of the positioning hole1221coincides with an axis of the rotation shaft23. A second end of the rotation shaft23is rotatably received in the positioning hole1221.

As shown inFIGS.4to7, in order to improve the service life of the portable fan provided in the present embodiment, the airflow portion20further includes a bearing portion24. An outer ring of the bearing portion24is fixed in the positioning hole1221, and an inner ring of the bearing portion24sleeves the second end of the rotation shaft23. By disposing the bearing portion24between the positioning hole1221and the rotation shaft23, and by receiving the outer ring of the bearing portion24in the positioning hole1221and arranging the inner ring to sleeve the second end of the rotation shaft23, direct friction between the positioning hole1221and the rotation shaft23can be avoided, such that the service life of the portable fan is effectively improved.

As shown inFIGS.4and5, in an embodiment, the bearing portion24includes a rolling bearing, and the airflow portion20further includes a limiting member25. The limiting member25is mounted at the second end of the rotation shaft23. The bearing portion24is disposed between the limiting member25and the first end of the rotation shaft23. By arranging the limiting member25on the second end of the rotation shaft23, a radial movement of the rolling bearing can be effectively limited.

As shown inFIGS.4and5, in an embodiment, in order to facilitate mounting of the rolling bearing, a plurality of bearing portions24are arranged. An inner flange12211is arranged on an inner wall of the positioning hole1221. The inner flange12211is disposed between two adjacent bearing portions24to enable the two adjacent bearing portions24to be spaced apart from each other. By arranging the limiting member25on the second end of the rotation shaft23, the inner ring of the rolling bearing can be effectively limited. By arranging the inner flange12211on the inner wall of the positioning hole1221, the outer ring of the bearing can be effectively limited. In this way, the rolling bearing can be mounted effectively.

In an embodiment, the bearing portion24is a ball bearing, and a lubricant is provided in the ball bearing.

In an embodiment, the bearing portion24is a ceramic bearing, and a lubricant is provided in the ceramic bearing.

In an embodiment, the bearing portion24is a magnetic levitation bearing.

In an embodiment, the airflow portion20further includes an elastic member, the elastic member sleeves the rotation shaft23. Two ends of the elastic member respectively abut against the inner ring of the rolling bearing and the rotation air blades21. The elastic member applies an elastic force on the inner ring of the rolling bearing in a direction away from the air inlet111. By arranging the elastic member, the rolling bearing can be pre-tensioned, and the service life of the rolling bearing is effectively improved.

As shown inFIGS.6and7, in an embodiment, in order to improve the service life of the portable fan of the present embodiment, the bearing portion24includes a slide bearing. The airflow portion20further includes two sealing rings26. The two sealing rings26both sleeve the rotation shaft23and are respectively located on two sides of the slide bearing. By arranging the slide bearing between the rotation shaft23and the positioning hole, and by arranging the inner ring of the slide bearing to be fixedly connected to the second end of the rotation shaft23and arranging the outer ring to be fixedly connected to the fixation hole, friction between the rotation shaft23and the positioning hole1221can be converted into friction between the inner ring and the outer ring of the slide bearing. In this way, the friction between the rotation shaft23and the positioning hole1221is avoided, and the service life of the portable fan is effectively improved.

As shown inFIGS.4to7, in an embodiment, the handheld portion30includes a third housing32and a fourth housing33connected to the third housing32. The mounting cavity34is formed between the third housing32and the fourth housing33.

As shown inFIGS.4to7, in an embodiment, the first housing11includes a housing body112and an air duct liner113. The air duct liner113is mounted on the housing body112. The air duct1131is defined inside the air duct liner113. The air guiding cavity13is formed between the air duct liner113and the second housing12.

Since a single-phase motor is inexpensive, most of small-sized handheld portable fans on the market are driven by single-phase motors. However, since the single-phase motor has a low rotational speed, a strong airflow cannot be provided, and a poor user experience is provided. In order to enable the small-sized handheld portable fan to provide stronger airflow, a high-speed motor needs to be arranged for driving. However, the high-speed motor occupies a large space, and the portable fan may be worn and torn.

In order to solve the above problem, the drive portion22is a three-phase motor. Since the drive portion22is the three-phase motor, a rotation speed of the rotation air blades21can be effectively increased, and the portable fan in this embodiment can provide a stronger airflow, the user experience is improved. In addition, due to the high rotation speed of the three-phase motor, in order to avoid sharp wear between the rotation shaft and the positioning hole due to the high-speed rotation and to ensure the service life of the portable fan, in the portable fan of the present embodiment, a bearing portion is disposed between the positioning hole and the rotation shaft. The bearing portion enables the friction between the positioning hole and the rotation shaft to be converted from sliding friction to rolling friction inside the bearing portion, such that wear and tear between the positioning hole and the rotation shaft can be avoided, the service life of the portable fan is effectively improved.

As shown inFIGS.1to7, in an embodiment, the handheld portion30is arranged with a charging port35. The charging port35is electrically connected to the power supply assembly31. By arranging the charging port35on the handheld portion30and enabling the charging port35to be electrically connected to the power supply assembly31, the power supply assembly31can be electrically connected to an external power supply through the charging port35, such that an operating endurance of the portable fan is ensured.

In an embodiment, a discharging port is arranged on the handheld portion that is electrically connected to the power supply assembly. The discharging port is electrically connected to an external electronic device. The discharging port enables electric power to be transmitted from the power supply assembly to the external electronic device.

In an embodiment, the air inlet is arranged with a grill assembly. The grill assembly includes a first grill member and a second grill member. The first grill member is fixedly connected to the first housing. The second grill member is pivotally connected to the first grill member. The first grill member defines a plurality of first openings. The second grill member defines a plurality of second openings. The plurality of first openings and the plurality of second openings are in one-to-one correspondence with each other. The second grill member has a shielding state that completely shields the first openings and an open state in which the first openings and the second openings overlap with each other. By rotating the second grill member, the second grill member can be switched between the shielding state and the open state. The grill assembly provided in this embodiment can effectively adjust the amount of air intaken from the air inlet, such that the user experience is effectively improved.

In an embodiment, the air duct portion10and the handheld portion30are fixedly connected to each other. Of course, in other embodiments, the air duct portion10and the handheld portion30may be pivotally connected to each other.

In an embodiment, the third housing32and the first housing11are integrally molded to form a one-piece structure, and the fourth housing33and the second housing12are integrally molded to form a one-piece structure

In another embodiment, the third housing32is pivotally connected to the first housing11, and the fourth housing33is pivotally connected to the second housing12. A pivot shaft between the third housing32and the first housing11is coaxial with a pivot shaft of the fourth housing33and the second housing12.

In summary, the portable fan provided in the present embodiment has at least the following beneficial technical effect. The drive portion22, which is driveably connected to the rotation air blades21, is configured as the stator221and the rotor222sleeving the outside of the stator221. The rotor222is fixedly mounted on the rotation air blades21and is coaxially arranged with the rotation air blades21. In addition, the stator221fixedly sleeves the positioning protruding post122. In this way, the driving force generated by the drive portion22can be directly transmitted to the rotation air blades21through the rotor222, the transmission device between the drive portion22and the rotation air blades21is omitted, such that the transmission efficiency of the portable fan is improved.