CN215860872U

CN215860872U - Portable fan

Info

Publication number: CN215860872U
Application number: CN202121677749.1U
Authority: CN
Inventors: 宋国伟
Original assignee: Shenzhen Ranvoo Technology Co Ltd
Current assignee: Shenzhen Ranvoo Technology Co Ltd
Priority date: 2021-07-22
Filing date: 2021-07-22
Publication date: 2022-02-18
Anticipated expiration: 2031-07-22

Abstract

The utility model discloses a portable fan, which comprises a shell, a fan wheel, a battery and a circuit board, wherein the circuit board is provided with a charging chip electrically connected with the battery, a charging input end for connecting the charging chip with an external power supply and a charging protection circuit connected between the charging input end and the charging chip, the charging protection circuit comprises a field effect tube and a control circuit connected with the field effect tube, a source electrode and a drain electrode of the field effect tube are respectively connected with the charging input end and the input end of the charging chip, a grid electrode is connected with the control circuit, the control circuit is used for adjusting the gate voltage of the field effect transistor according to the charging voltage at the charging input end, the field effect transistor is conducted so as to conduct the power supply connection between the charging input end and the charging chip, or the field effect tube is disconnected to cut off the power supply connection between the charging input end and the charging chip.

Description

Portable fan

Technical Field

The utility model relates to the technical field of household appliances, in particular to a portable fan.

Background

At present, along with the increasing of electronic product types, more and more quick charging adapters appear on the market, the quality of the quick charging adapters is uneven, the voltage output is also divided into different sizes such as 5V, 9V, 12V, 20V and the like, the charging voltage of a portable fan is often a fixed voltage value, if the quick charging adapter higher than the charging voltage is connected with the portable fan and an external power supply by mistake, a charging chip may be damaged, the charging function may fail, and accidents such as shell melting, explosion and the like may be caused seriously.

SUMMERY OF THE UTILITY MODEL

In order to solve the existing technical problems, the utility model provides a portable fan which is safer to charge.

In order to achieve the above purpose, the technical solution of the embodiment of the present invention is realized as follows:

a portable fan comprises a shell, a fan wheel, a battery and a circuit board, wherein the battery and the circuit board are arranged in the shell and are electrically connected with the fan wheel, a charging chip electrically connected with the battery, a charging input end for connecting the charging chip with an external power supply and a charging protection circuit connected between the charging input end and the charging chip are arranged on the circuit board, the charging protection circuit comprises a field effect tube and a control circuit connected with the field effect tube, a source electrode and a drain electrode of the field effect tube are respectively connected with the charging input end and the input end of the charging chip, a grid electrode is connected with the control circuit, the control circuit is used for adjusting the grid voltage of the field effect tube according to the charging voltage at the charging input end, the field effect tube is conducted so as to conduct the power supply connection between the charging input end and the charging chip, or the field effect tube is disconnected to cut off the power supply connection between the charging input end and the charging chip.

The control circuit comprises a triode with an emitting electrode connected with the charging input end, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein the first resistor and the second resistor are connected between the charging input end and the base electrode of the triode in series, the third resistor is connected between the collector electrode of the triode and the source electrode of the field effect transistor, and the fourth resistor is connected between the collector electrode of the triode and the electrode ground.

The portable fan further comprises an overcharge protection circuit connected with the anode and the cathode of the battery, and the overcharge protection circuit controls the charging circuit for charging the battery to be disconnected when the voltage of the battery is higher than a charging threshold value.

The overcharge protection circuit further comprises a charge overcurrent protection circuit, and the charge overcurrent protection circuit controls the charging circuit for charging the battery to be switched off when the charging current of the battery is greater than the current threshold value.

The portable fan further comprises an over-discharge protection circuit connected with the anode and the cathode of the battery, and the over-discharge protection circuit controls the discharge circuit of the battery to be disconnected when the voltage of the battery is lower than the lowest discharge voltage.

The over-discharge protection circuit further comprises a discharge over-current protection circuit, and the discharge over-current protection circuit controls the discharge circuit of the battery to be switched off when the discharge current is larger than the maximum discharge current.

The over-discharge protection circuit further comprises a short circuit detection circuit, and the short circuit detection circuit controls the discharge circuit of the battery to be disconnected when the discharge circuit of the battery is short-circuited.

The shell is a neck wearing frame for hanging a neck fan, the neck wearing frame comprises a first body and a second body which are connected with each other, the fan wheel is arranged in the first body and the second body respectively, and the battery and the circuit board are further arranged in the first body.

The space in the first body is separated by a partition plate to form an air duct and an accommodating cavity, and the battery and the circuit board are accommodated in the accommodating cavity.

Wherein the shell is a handle of the handheld fan; or the shell is a bracket of the desktop fan.

The portable fan provided by the above embodiment includes a charging input end for connecting the charging chip with an external power supply and a charging protection circuit connected between the charging input end and the charging chip, wherein the charging protection circuit includes a field effect transistor and a control circuit connected with the field effect transistor, the control circuit is used for adjusting the gate voltage of the field effect transistor according to the charging voltage at the charging input end, the field effect transistor is connected to enable the power supply connection between the charging input end and the charging chip to be connected, or the field effect transistor is disconnected to cut off the power supply connection between the charging input end and the charging chip, so that the charging protection circuit can ensure that the charging voltage connected with the charging input end is automatically disconnected when being too high, thereby preventing the charging input end from being connected with the too high charging voltage to damage the charging chip and cause accidents such as shell melting or explosion.

Drawings

FIG. 1 is a perspective view of a portable fan according to one embodiment;

FIG. 2 is an exploded view of the portable fan of FIG. 1;

FIG. 3 is a circuit diagram of a portable fan according to an embodiment;

FIG. 4 is a schematic diagram of a charge protection circuit of a portable fan according to an embodiment;

fig. 5 is a schematic diagram of an overcharge protection circuit and an overdischarge protection circuit of a portable fan according to an embodiment.

Detailed Description

The technical scheme of the utility model is further elaborated by combining the drawings and the specific embodiments in the specification. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. In the following description, reference is made to the expression "some embodiments" which describe a subset of all possible embodiments, but it should be understood that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict.

It will also be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "inner," "outer," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1 to 3, an embodiment of the present application provides a portable fan, including a housing 10, a fan wheel 20, a battery 31 disposed in the housing 10 and electrically connected to the fan wheel 20, and a circuit board 32, wherein the circuit board 32 is provided with a charging chip U0 electrically connected to the battery 31, a charging input terminal VI N for connecting the charging chip U0 to an external power source, and a charging protection circuit 33 connected between the charging input terminal VI N and the charging chip U0, the charging protection circuit 33 includes a fet Q2 and a control circuit 331 connected to the fet Q2, a source and a drain of the fet Q2 are respectively connected to the charging input terminal VI N and an input terminal of the charging chip U0, a gate of the fet Q2 is connected to the control circuit 331, the control circuit 331 is configured to adjust a gate voltage of the fet Q2 according to a charging voltage at the charging input terminal VI N, the fet Q2 is turned on to make the power supply connection between the charging input VI N and the charging chip U0 conductive, or the fet Q2 is turned off to break the power supply connection between the charging input VI N and the charging chip U0. Specifically, when the charging voltage at the charging input terminal VI N is higher than a preset value, the control circuit 331 adjusts the gate voltage of the field-effect transistor Q2 to be smaller than a turn-on voltage, and the field-effect transistor Q2 is turned off to cut off the power supply connection between the charging input terminal VI N and the charging chip U0; when the charging voltage at the charging input terminal VI N is lower than the preset value, the control circuit 331 adjusts the gate voltage of the field effect transistor Q2 to be greater than the turn-on voltage, the field effect transistor Q2 is turned on, and the power supply connection between the charging input terminal VI N and the charging chip U0 is turned on.

In the above embodiment, the portable fan includes the charging input terminal VI N for connecting the charging chip U0 with an external power supply, and the charging protection circuit 33 connected between the charging input terminal VI N and the charging chip U0, where the charging protection circuit 33 includes the fet Q2 and the control circuit 331 connected to the fet Q2, when the charging voltage at the charging input terminal VI N is higher than the preset value, the control circuit 331 adjusts the gate voltage of the fet Q2 to be smaller than the turn-on voltage, and the fet Q2 is turned off to cut off the power supply connection between the charging input terminal VI N and the charging chip U0; when the charging voltage of input VI N department of charging is less than the default, control circuit 331 adjusts field effect transistor Q2's grid voltage and is greater than opening voltage, field effect transistor Q2 switches on, the power supply between input VI N of charging and the chip U0 that charges is connected and is switched on, so, charging protection circuit 33 can ensure charging input VI N connection charging voltage automatic disconnection when too high, lead to damaging the chip that charges when avoiding charging input VI N and too high charging voltage to be connected, arouse the emergence of accidents such as melting the shell or explosion.

Optionally, referring to fig. 4, the control circuit 331 includes a transistor Q1 having an emitter E connected to the charging input terminal VI N, a first resistor R1 and a second resistor R2 connected in series between the charging input terminal VI N and the base B of the transistor Q1, a third resistor R3 connected between the collector C of the transistor Q1 and the source of the fet Q2, and a fourth resistor R4 connected between the collector C of the transistor Q1 and the ground. The charging input end VI N can be selected as a standard type-C interface, a USB interface and the like, and can be connected with a mains supply through various power adapters in a plug-in connection manner to obtain charging electric energy; or the charging power can be obtained by connecting various power lines with a mobile power supply, electronic equipment and the like. When the voltage of the external power supply connected to the charging input end VI N is higher than a preset value, the triode Q1 is cut off, the grid voltage of the field-effect transistor Q2 is divided by the fourth resistor for the voltage at the charging input end VI N, and the field-effect transistor Q2 is disconnected to cut off the power supply connection between the charging input end VI N and the charging chip U0; when the voltage of the external power supply connected to the charging input terminal VI N is lower than a preset value, the triode Q1 is turned on, the gate voltage of the field-effect transistor Q2 is equal to the voltage at the charging input terminal VI N, and the field-effect transistor Q2 is turned off, so that the power supply connection between the charging input terminal VI N and the charging chip U0 is turned on. In an alternative specific example, the preset value is 5.5V. Therefore, the control circuit 331 is provided with the triode Q1 as a control element for controlling the on-off of the field effect transistor Q2, so that the control can be more accurate.

Optionally, referring to fig. 5, the battery further includes an overcharge protection circuit 34 connected to the positive electrode BAT + and the negative electrode BAT-of the battery 31, where the overcharge protection circuit 34 controls a charging circuit that charges the battery 31 to be disconnected when the voltage of the battery 31 is higher than a charging threshold. The overcharge protection circuit 34 may be disposed on the circuit board 32, and mainly includes an overcharge chip U1, the overcharge chip U1 may be a known chip, a charging threshold may be set according to a capacity of the battery 31, a comparison between a voltage of the battery 31 and the charging threshold in the overcharge protection circuit 34 may also be implemented by using a comparator, and the comparator outputs a high level signal or a low level signal to the switch circuit according to a comparison result between the voltage of the battery 31 and the charging threshold, so as to control the charging circuit that charges the battery 31 to be turned off. Taking a portable fan as an example, the charging threshold may be 4.25V. Optionally, the overcharge protection circuit further includes a charging overcurrent protection circuit 341, and the charging overcurrent protection circuit 341 controls the charging circuit for charging the battery 31 to be turned off when the charging current of the battery 31 is greater than the current threshold. The charging current is detected by the charging overcurrent protection circuit 341, so as to ensure that the charging current is not higher than the current threshold value, and avoid the damage to the service life of the battery 31 or the occurrence of safety accidents caused by the matching of the charging current and the performance of the battery 31. Correspondingly, the comparison between the charging current of the battery 31 and the current threshold in the charging overcurrent protection circuit 341 can also be implemented by using a comparator, and the comparator outputs a high level signal or a low level signal to the switch circuit according to the comparison result between the charging current of the battery 31 and the current threshold, so as to control the charging circuit for charging the battery 31 to be switched off. The disconnection of the charging circuit for controlling the charging of the battery 31 may refer to disconnection of any on-off node in a loop formed by connection between the charging input terminal VI N and the battery 31, for example, when it is detected that the voltage of the battery 31 is higher than a charging threshold or when it is detected that the charging current of the battery 31 is greater than a current threshold, the overcharge chip U1 sends a control signal to the charge chip U0 to control the charge chip U0 to stop charging the battery 31; or when detecting that the voltage of the battery 31 is higher than the charging threshold or detecting that the charging current of the battery 31 is larger than the current threshold, the overcharge chip U1 disconnects the positive electrode BAT + and the negative electrode BAT "of the battery 31 to cut off the charging circuit for charging the battery 31.

Optionally, the battery pack further comprises an over-discharge protection circuit 35 connected to the positive electrode BAT + and the negative electrode BAT —, where the over-discharge protection circuit 35 controls the discharge circuit of the battery 31 to be turned off when the voltage of the battery 31 is lower than the lowest discharge voltage. The over-discharge protection circuit 35 may be disposed on the circuit board 32, and mainly includes an over-discharge chip U2, the over-discharge chip U2 may be a known chip, the lowest discharge voltage may be set according to the capacity of the battery 31, the comparison between the voltage of the battery 31 and the lowest discharge voltage in the over-discharge protection circuit 35 may also be implemented by using a comparator, and the comparator outputs a high level signal or a low level signal to the switch circuit according to the comparison result between the voltage of the battery 31 and the lowest discharge voltage, so as to control the discharge circuit of the battery 31 to be turned off. Taking a portable fan as an example, the minimum discharge voltage may be 3V. By setting the minimum discharge voltage, the protection function of the discharge over-discharge voltage can be achieved, so that the service life of the battery 31 is effectively prolonged. Optionally, the over-discharge protection circuit 35 further includes a discharge over-current protection circuit 351, and the discharge over-current protection circuit 351 controls the discharge circuit of the battery 31 to be turned off when the discharge current is greater than the maximum discharge current. The discharging overcurrent protection circuit 351 is arranged to detect the discharging current so as to ensure that the discharging current is not higher than the maximum discharging current, and the service life of the battery 31 is effectively prevented from being influenced by the overhigh temperature of the battery 31. Accordingly, the comparison between the discharge current and the maximum discharge current of the battery 31 in the discharge overcurrent protection circuit 351 can also be implemented by using a comparator, and the comparator outputs a high level signal or a low level signal to the switch circuit according to the comparison result between the charge current of the battery 31 and the current threshold value so as to control the discharge circuit of the battery 31 to be switched off. Optionally, the over-discharge protection circuit 35 further includes a short-circuit detection circuit 352, and the short-circuit detection circuit 352 controls the discharge circuit of the battery 31 to be disconnected when the discharge circuit of the battery 31 is short-circuited. When the short-circuit detection circuit 352 detects that the battery 31 is discharged and outputs an external short-circuit, the discharge circuit is controlled to be turned off, so that the battery 31 is not discharged any more, thereby preventing the occurrence of a malignant event such as explosion or ignition of the battery 31. The step of controlling the discharge circuit of the battery 31 to be disconnected may refer to that any on-off node in a loop formed by the connection between the battery 31 and a load is disconnected, and for example, when it is detected that the voltage of the battery 31 is lower than the lowest discharge voltage, the discharge current is detected to be greater than the maximum discharge current, or a short circuit is detected, the overdischarge chip U2 sends a control chip to the management control unit of the battery 31 to control the battery 31 to stop discharging; or the over-discharge chip U2 may directly disconnect the positive electrode BAT + and the negative electrode BAT "of the battery 31 to cut off the discharge circuit of the battery 31.

Referring to fig. 2 again, the portable fan is a neck hanging fan that can be worn around the neck of a user. The shell 10 is a neck wearing frame of a neck hanging fan, the neck wearing frame comprises a first body 11 and a second body 12 which are connected with each other, and the fan wheel 20, the battery 31 and the circuit board 32 are arranged in the first body 11 and the second body 12 respectively. The whole arc that is with human neck shape looks adaptation of frame is worn to the neck, and the neck is worn the frame and is connected by first body 11 and second body 12 and constitute, sets up fan wheel 20 respectively in first body 11 and the second body 12 and control battery 31 and the circuit that corresponds fan wheel 20 work, and two internal fan wheels 20 form function complete relatively, independent whole respectively to convenient equipment, maintenance. The spaces in the first body 11 and the second body 12 are separated by a partition 13 to form an air duct and an accommodating chamber, and the battery 31 and the circuit board 32 are accommodated in the accommodating chamber. The partition 13 partitions the inner spaces of the first body 11 and the second body 12, so that the layout can be optimized, and the arrangement of the battery 31 and the circuit board 32 can be prevented from increasing wind resistance. In another embodiment, the fan wheel 20 and the battery 31 may be respectively disposed in the first body 11 and the second body 12, the circuit board 32 is not disposed in the second body 12, and the circuit board 32 is only disposed in the first body 11, so that the fan wheels 20 in the two bodies are controlled by the same control switch.

It should be noted that the portable fan is not limited to a neck hanging fan, and in other embodiments, the portable fan may also be a handheld fan or a desktop small fan, and the housing 10 is a handle of the handheld fan; or, the housing 10 is a bracket of a desktop fan. The design of the circuit board 32 for controlling the operation of the impeller 20 can be the same as that described in the previous embodiments, and is not repeated herein.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. The scope of the utility model is to be determined by the scope of the appended claims.

Claims

1. A portable fan is characterized by comprising a shell, a fan wheel, a battery and a circuit board, wherein the battery and the circuit board are arranged in the shell and are electrically connected with the fan wheel, a charging chip electrically connected with the battery, a charging input end for connecting the charging chip with an external power supply and a charging protection circuit connected between the charging input end and the charging chip are arranged on the circuit board, the charging protection circuit comprises a field effect tube and a control circuit connected with the field effect tube, a source electrode and a drain electrode of the field effect tube are respectively connected with the charging input end and an input end of the charging chip, a grid electrode is connected with the control circuit, the control circuit is used for adjusting the grid voltage of the field effect tube according to the charging voltage at the charging input end, the field effect tube is conducted so as to conduct the power supply connection between the charging input end and the charging chip, or the field effect tube is disconnected to cut off the power supply connection between the charging input end and the charging chip.

2. The portable fan of claim 1, wherein the control circuit comprises a transistor having an emitter connected to the charging input, first and second resistors connected in series between the charging input and a base of the transistor, a third resistor connected between a collector of the transistor and a source of the fet, and a fourth resistor connected between the collector of the transistor and electrode ground.

3. The portable fan of claim 1 further comprising an overcharge protection circuit connected to the positive and negative poles of the battery, the overcharge protection circuit controlling the charging circuit that charges the battery to open when the voltage of the battery is above a charge threshold.

4. The portable fan of claim 3 wherein the overcharge protection circuit further comprises a charge overcurrent protection circuit that controls a charging circuit that charges the battery to open when a charging current of the battery is greater than a current threshold.

5. The portable fan of claim 1 further comprising an over-discharge protection circuit connected to the positive and negative poles of the battery, the over-discharge protection circuit controlling the discharge circuit of the battery to open when the voltage of the battery is below a minimum discharge voltage.

6. The portable fan of claim 5, wherein the over-discharge protection circuit further comprises a discharge over-current protection circuit that controls a discharge circuit of the battery to open when a discharge current is greater than a maximum discharge current.

7. The portable fan of claim 5 wherein the over-discharge protection circuit further comprises a short detection circuit that controls the discharge circuit of the battery to open when the discharge circuit of the battery is shorted.

8. The portable fan according to any one of claims 1 to 7, wherein the housing is a neck-wearing frame for hanging a neck fan, the neck-wearing frame comprises a first body and a second body connected with each other, the first body and the second body are respectively provided with the fan wheel therein, and the first body is further provided with the battery and the circuit board therein.

9. The portable fan of claim 8, wherein the space in the first body is partitioned by a partition to form an air duct and a receiving chamber, and the battery and the circuit board are received in the receiving chamber.

10. The portable fan of any one of claims 1 to 7 in which the housing is a handle of a hand-held fan; or the shell is a bracket of the desktop fan.