CN215256895U

CN215256895U - Mini fan

Info

Publication number: CN215256895U
Application number: CN202120901169.XU
Authority: CN
Inventors: 林丹阳
Original assignee: Shenzhen Yueyang Technology Co ltd
Current assignee: Shenzhen Yueyang Technology Co ltd
Priority date: 2021-04-28
Filing date: 2021-04-28
Publication date: 2021-12-21
Anticipated expiration: 2031-04-28

Abstract

The utility model discloses a mini fan, include: the outer barrel is provided with an accommodating cavity and a telescopic opening communicated with the accommodating cavity; the main body comprises an inner shell, a driving device and a fan blade assembly, wherein the inner shell is arranged in the accommodating cavity, the driving device is arranged at one end, close to the telescopic opening, of the inner shell, and the driving device is used for driving the fan blade assembly to rotate; the inner shell and the outer cylinder can be matched in a sliding way, so that the fan blade component has a first position extending out of the telescopic opening and a second position retracting into the accommodating cavity; the cover body is connected to the tail end of the output shaft of the driving device, and when the fan blade assembly is located at the second position, the cover body covers the expansion port. The utility model discloses among the technical scheme, behind the flabellum subassembly withdrawal holding chamber, connect and can cover in the terminal lid of output shaft and locate the expansion joint to prevent dust or foreign matter and get into the holding chamber through flexible mouthful, can avoid flabellum subassembly to be damaged or pollute from this, thereby can improve the protection effect and the dustproof effect to flabellum subassembly.

Description

Mini fan

Technical Field

The utility model relates to a life electrical apparatus technical field, in particular to mini fan.

Background

The handheld fan is popular with consumers because of its small size and portability. In the correlation technique, through with mini fan body and outer sleeve slidable fit realize the protection of accomodating to mini fan body to the user of being more convenient for goes out to carry. However, in the related art, after the mini fan body is received in the outer sleeve, the opening of the outer sleeve is exposed to the outside, so that foreign matters or dust can easily enter the outer sleeve, and damage or pollution to the fan blades is easily caused.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a mini fan aims at solving the technical problem who how to improve protection of flabellum and dustproof effect.

In order to achieve the above object, the utility model provides a mini fan includes:

the outer barrel is provided with an accommodating cavity and a telescopic opening communicated with the accommodating cavity;

the main body comprises an inner shell, a driving device and a fan blade assembly, wherein the inner shell is arranged in the accommodating cavity, the driving device is arranged at one end, close to the telescopic opening, of the inner shell, and the driving device is used for driving the fan blade assembly to rotate; the inner shell is matched with the outer cylinder in a sliding mode, so that the fan blade assembly has a first position extending out of the telescopic opening and a second position retracting into the accommodating cavity;

the cover body is connected to the tail end of the output shaft of the driving device, and when the fan blade assembly is located at the second position, the cover body covers the expansion port.

Optionally, the mini fan further includes a hand pulling member, and the hand pulling member is connected to a side of the cover body facing away from the accommodating cavity.

Optionally, the cover body is fixedly matched with an output shaft of the driving device to synchronously rotate along with the output shaft, and the fan blade assembly is connected to the cover body.

Optionally, the cover body is disposed in a plate shape, and when the cover body covers the telescopic opening, the end surface of the outer cylinder abuts against one surface of the cover body facing the accommodating cavity.

Optionally, the lid orientation the concave spacing groove that is equipped with of one side in holding chamber, the spacing groove is followed the week of lid extends, the lid is located during the flexible mouthful, the tip of urceolus with the spacing groove butt cooperation.

Optionally, when the cover body covers the telescopic opening, the joint of the outer surface of the cover body and the outer surface of the outer barrel is in smooth transition.

Optionally, the fan assembly includes a plurality of fans distributed along the circumferential direction of the output shaft, and the fans are rotatably connected to the cover body to have an expanded state in which the free ends thereof are away from the output shaft, and a collapsed state in which the free ends thereof are close to the output shaft.

Optionally, the fan blade is a soft glue fan blade.

Optionally, the driving device is rotatably mounted to the inner shell, so that the output shaft has an inclined position, and the output shaft and the extension direction of the inner shell are arranged at an included angle in the inclined position.

Optionally, a sliding groove is formed in the inner wall surface of the outer cylinder, the sliding groove extends along the opening direction of the expansion opening, a sliding protrusion is convexly arranged on the outer wall surface of the inner shell, and the sliding protrusion is in slidable fit with the sliding groove.

The mini fan of the utility model has the advantages that the inner shell and the outer cylinder can be matched in a sliding way, and the driving device and the fan blade component are arranged in the inner shell, so that the fan blade component can extend out of the telescopic opening or retract into the holding cavity along with the movement of the inner shell, thereby playing a role in accommodating the fan blade component in an idle state and being convenient for a user to carry; after the fan blade assembly retracts into the accommodating cavity, the cover body connected to the tail end of the output shaft can cover the extending port to prevent dust or foreign matters from entering the accommodating cavity through the extending port, so that the fan blade assembly can be prevented from being damaged or polluted, and the protection effect and the dustproof effect on the fan blade assembly can be improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an embodiment of a mini fan according to the present invention;

FIG. 2 is a schematic structural diagram of another embodiment of a mini fan according to the present invention;

FIG. 3 is a schematic structural diagram of another embodiment of a mini fan according to the present invention;

FIG. 4 is a schematic cross-sectional view of an embodiment of a mini fan according to the present invention;

FIG. 5 is a schematic cross-sectional view of another embodiment of a mini fan according to the present invention;

FIG. 6 is a schematic structural diagram of another embodiment of a mini fan according to the present invention;

fig. 7 is an exploded view of the mini fan according to an embodiment of the present invention.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)	Reference numerals	Name (R)
						10	Outer cylinder	11	Containing cavity	12	Telescopic mouth
20	Inner shell	30	Drive device	40	Fan blade assembly
						31	Output shaft	50	Cover body	60	Hand pulling piece
51	Limiting groove	70	Protective shell	21	Avoiding groove
						13	Sliding chute	22	Sliding projection

The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that, if directional indications (such as upper, lower, left, right, front and rear … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description relating to "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed 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 at least one such feature. In addition, the meaning of "and/or" appearing throughout is to include three juxtapositions, exemplified by "A and/or B," including either the A or B arrangement, or both A and B satisfied arrangement. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The utility model provides a mini fan, this mini fan is the small-size mini fan that can hand.

In the embodiment of the present invention, as shown in fig. 1 to 7, the mini fan includes: the outer barrel 10 is provided with an accommodating cavity 11 and a telescopic port 12 communicated with the accommodating cavity 11; the fan blade assembly comprises a main body, a fan blade assembly and a fan blade assembly, wherein the main body comprises an inner shell 20, a driving device 30 and a fan blade assembly 40, the inner shell 20 is installed in the accommodating cavity 11, the driving device 30 is installed at one end, close to the expansion port 12, of the inner shell 20, and the driving device 30 is used for driving the fan blade assembly 40 to rotate; the inner shell 20 is slidably matched with the outer cylinder 10, so that the fan blade assembly 40 has a first position extending out of the telescopic opening 12 and a second position retracting into the accommodating cavity 11; the cover 50 is connected to the end of the output shaft 31 of the driving device 30, and when the fan blade assembly 40 is located at the second position, the cover 50 covers the expansion port 12.

The outer cylinder 10 may be a cylinder or a square cylinder, and is not limited herein; for example, the outer tube 10 may be configured as a cylinder, so that the space occupied by the outer tube 10 having a cylindrical surface is smaller, thereby being more convenient to store and carry, and the cylindrical surface can increase the fitting area with the human hand, so as to improve the hand feeling experience of the user holding the outer tube 10. The opening 12 may be formed at the end of the outer tube 10 so that the inner housing 20 can be extended out of the opening 12 and still maintain a sufficient engagement length with the outer tube 10. The inner casing 20, the driving device 30 and the fan blade assembly 40 together form a main body of the mini fan, and the outer casing 10 can be used for accommodating the main body to protect the main body. The inner housing 20 is slidably engaged with the outer cylinder 10, the outer wall surface of the inner housing 20 may directly slide against the inner wall surface of the outer cylinder 10, or may be engaged with the sliding track of the sliding groove 13, which is not limited herein. The inner housing 20 may form a mounting cavity for mounting a battery, which may supply power to the driving device 30, and a circuit board, which may control the driving device 30 to operate or stop.

The driving device 30 is mounted at one end of the inner housing 20 close to the expansion joint 12, that is, during the sliding process of the inner housing 20 from the accommodating cavity 11 to the outside, the output shaft 31 of the driving device 30 firstly extends out of the expansion joint 12. It should be noted that the driving device 30 may be installed inside the inner casing 20, or may be installed outside the inner casing 20, and only needs to be close to the expansion joint 12; for example, if the driving device 30 is installed inside the inner casing 20, the output shaft 31 needs to penetrate through the end of the inner casing 20 for connecting the fan blade assembly 40 and the cover 50. If the driving device 30 is installed outside the inner housing 20, the driving device 30 may be fixedly installed on the inner housing 20, or may be rotatably installed on the inner housing 20, which is not limited herein; it should be noted that, since the cover 50 is connected to the end of the output shaft 31, when the driving device 30 retracts into the accommodating cavity 11, the axial direction of the output shaft 31 needs to be consistent with the opening direction of the telescopic opening 12, so as to ensure that the cover 50 can effectively cover the telescopic opening 12.

The fan blade assembly 40 may be directly connected to the output shaft 31, or may be indirectly connected to the output shaft 31 through a turntable, which is not limited herein, and only needs to satisfy that the fan blade assembly 40 can rotate along with the output shaft 31. When the driving device 30 extends out of the telescopic opening 12, the fan blade assembly 40 can move to the first position along with the output shaft 31 and drive the airflow under the rotation driving of the output shaft 31 to generate a fanning effect; when the driving device 30 retracts into the accommodating cavity 11, the fan blade assembly 40 can move to the second position along with the output shaft 31.

The cover 50 may be plate-shaped or cover-shaped, and is not limited herein, and only needs to cover the expansion opening 12 with the cover 50 after the main body is integrally retracted into the accommodating cavity 11. The cover 50 may close the flexible opening 12, or may form a certain gap with the periphery of the flexible opening 12. When the lid 50 is fitted to the spout 12, an end surface of the lid 50 may abut against an end surface of the outer tube 10, or a circumferential surface of the lid 50 may abut against an inner wall surface of the outer tube 10, which is not limited herein. The cover 50 may be connected and fixed to the output shaft 31, or may be indirectly engaged with the output shaft through a bearing, which is not limited herein. For example, a fixing cylinder may be protruded from a surface of the cover 50 facing the accommodating cavity 11, and the fixing cylinder is fixedly engaged with the output shaft 31, so as to improve the engaging strength between the cover 50 and the output shaft 31. After the cover 50 covers the expansion opening 12, the dust-proof and foreign-matter-proof function can be performed to the accommodating cavity 11, so that the fan blade assembly 40 can be prevented from being damaged by foreign matters or polluted by dust when the mini fan is in an idle state; in addition, the cover 50 covers the expansion opening 12, so that the appearance integrity of the mini fan in an idle state can be improved, and the visual effect can be improved. In practical application, a sealing ring can be further disposed at the abutting position of the cover 50 and the outer cylinder 10 to achieve a waterproof effect, so that the self-protection performance of the mini fan is improved.

It should be noted that, when the mini fan works, as shown in fig. 3, the fan blade assembly 40 is in the unfolded state where the free end is far away from the output shaft 31, the air outlet direction of the fan blade assembly 40 is towards the tail end of the output shaft 31, that is, towards the cover 50, in order to prevent the cover 50 from shielding the air outlet flow of the fan blade assembly 40, the free end of the fan blade assembly 40 in the unfolded state needs to protrude out of the peripheral wall of the cover 50, and the area of the cover 50 is adapted to the sectional area of the expansion opening 12, that is, the fan blade assembly 40 cannot normally retract into the accommodating cavity 11 through the expansion opening 12 in the unfolded state. Therefore, in the present embodiment, as shown in fig. 2 and 4, the fan blade assembly 40 further has a folded state in which the free end is close to the output shaft 31, and in the folded state, the fan blade assembly 40 is completely located within the covering range of the cover 50, so as to normally pass through the telescopic opening 12. The fan blade assembly 40 can be detachably mounted on the output shaft 31 to realize the mutual switching of the unfolding state and the folding state through a dismounting and reassembling mode; the switch can also be rotatably arranged on the output shaft 31 to realize the switching between the unfolding state and the folding state in a rotating mode; furthermore, flabellum subassembly 40 still can set up to the flexible glue flabellum, and the flexible glue flabellum can hang down naturally under the action of gravity when not being rotated by output shaft 31 to draw in naturally, and when output shaft 31 was rotatory, the flexible glue flabellum can expand automatically under the effect of centrifugal force, from this, need not the user again manually switch flabellum subassembly 40's two kinds of states, improved mini fan's convenience in utilization.

The mini fan of the utility model has the advantages that the inner shell 20 and the outer shell 10 can be matched in a sliding way, and the driving device 30 and the fan blade assembly 40 are arranged on the inner shell 20, so that the fan blade assembly 40 can extend out of the telescopic opening 12 or retract into the accommodating cavity 11 along with the movement of the inner shell 20, and the fan blade assembly 40 in an idle state can be accommodated, thereby being convenient for a user to carry; after the fan blade assembly 40 retracts into the accommodating cavity 11, the cover 50 connected to the end of the output shaft 31 covers the extending opening 12 to prevent dust or foreign matters from entering the accommodating cavity 11 through the extending opening 12, so that the fan blade assembly 40 is prevented from being damaged or polluted, and the protection effect and the dustproof effect on the fan blade assembly 40 can be improved. In addition, since the cover 50 is connected to the output shaft 31 of the driving device 30, the cover can move with the inner casing 20 to open or close the expansion port 12, and thus, a user does not need to separately load and unload the expansion port, thereby further improving the convenience of the mini fan.

In an embodiment, as shown in fig. 1 to 7, the mini fan further includes a handle 60, and the handle 60 is connected to a side of the cover 50 facing away from the receiving cavity 11. The cover 50 has a covering surface facing the accommodating cavity 11 and an appearance surface facing away from the accommodating cavity 11, and the hand-pulling member 60 is protruded from the appearance surface for the user to grasp, so as to facilitate the user to pull out the fan blade assembly 40 by applying force. The specific shape of the hand piece 60 is not limited, and only needs to be satisfied to provide a grasping point for a user; for example, the outer surface of the hand-pulling piece 60 can be set to be a convex arc surface to increase the fitting area with the hand of the user, improve the grabbing comfort level of the user, and simultaneously avoid the corner angle from damaging the user, so as to improve the safety performance of the mini fan. The hand piece 60 can be integrally injection molded with the cover 50 to improve the processing efficiency and reduce the processing cost.

Specifically, as shown in fig. 2 and 3, the cover 50 is fixedly engaged with the output shaft 31 of the driving device 30 to rotate synchronously with the output shaft 31, and the fan assembly 40 is connected to the cover 50. The fan assembly 40 is connected to the covering surface of the cover 50 to ensure that the fan assembly 40 is completely located in the accommodating cavity 11 when the cover 50 is covered on the expansion opening 12. The fan blade assembly 40 is close to the outer periphery of the cover 50 at the connecting position of the covering surface to reduce the shielding of the cover 50 on the fan blade assembly 40 in the unfolding state, thereby improving the effective air output of the fan blade assembly 40. Connect flabellum subassembly 40 in lid 50, both reduced the influence of lid 50 to flabellum subassembly 40 air output, need not to add the carousel again to improve the utilization ratio of lid 50, simplified the overall structure of mini fan.

In one embodiment, as shown in fig. 2 and 3, the fan assembly 40 includes a plurality of fan blades distributed along the circumference of the output shaft 31, and the fan blades are rotatably connected to the cover 50 to have an expanded state in which the free ends thereof are away from the output shaft 31 and a collapsed state in which the free ends thereof are close to the output shaft 31. The number of the fan blades may be two, or may be three or more, which is not limited herein. The lid of lid 50 closes the face protruding and is equipped with the splice bar, and the first shaft hole has been seted up to the splice bar, and the flabellum forms has first pivot, and first pivot extends and but with the rotatable cooperation of first shaft hole along the tangential direction of lid 50 to realize the rotatable of flabellum. The user can manually toggle the fan blade from the folded state to the unfolded state, or from the unfolded state to the folded state, so as to improve the convenience of the fan blade assembly 40 in switching the two states.

Specifically, the flabellum sets up to the flexible glue flabellum, specifically can be PVC flexible glue flabellum to rotate to the state of drawing in through the mode of natural flagging, or rotate to the state of expanding automatically under output shaft 31's centrifugal force effect, thereby need not the user and stir, further improve mini fan's convenience in utilization. In practical application, the splice bar can include fixed part and detachable part, and the fixed part encloses with detachable part and closes formation first shaft hole, and the fixed part passes through the fastener with detachable part and can dismantle the connection to realize being connected of dismantling of flabellum and lid 50, thereby convenience of customers changes the flabellum, with the whole life of extension mini fan.

In an embodiment, as shown in fig. 4 and 5, the cover 50 is disposed in a plate shape, and when the cover 50 is disposed on the expansion opening 12, an end surface of the outer cylinder 10 abuts against a surface of the cover 50 facing the accommodating cavity 11. When the cover body 50 arranged in a plate shape is covered on the expansion port 12, the whole length size of the mini fan can be reduced, so that the occupied space is reduced; in addition, in combination with the embodiment that the fan blade assembly 40 is connected to the cover 50, the cover 50 disposed in a plate shape can make the fan blade assembly 40 more fully unfolded, so as to improve the fan efficiency. When the cover 50 covers the flexible opening 12, the covering surface abuts against the end surface of the outer cylinder 10, so as to seal the flexible opening 12 and prevent the main body from being pushed and pressed continuously toward the accommodating cavity 11, thereby effectively protecting the fan blade assembly 40 and the driving device 30.

Specifically, as shown in fig. 4 and 5, a limiting groove 51 is concavely disposed on one surface of the cover 50 facing the accommodating cavity 11, the limiting groove 51 extends along a peripheral edge of the cover 50, and when the cover 50 is covered on the expansion port 12, an end of the outer cylinder 10 is abutted against and matched with the limiting groove 51. The limiting groove 51 is concavely arranged on the covering surface of the cover body 50 and is close to the peripheral edge of the covering surface, the limiting groove 51 is provided with a limiting peripheral wall and a limiting end wall, the limiting end wall is used for abutting against the end surface of the outer cylinder 10, and the limiting peripheral wall is used for limiting and abutting against the inner wall surface of the outer cylinder 10, so that when the cover body 50 receives radial acting force, the acting force is not transmitted to the driving device 30, but is transmitted to the cylinder wall of the outer cylinder 10 through the limiting peripheral wall, and the driving device 30 can be effectively protected.

In practical applications, as shown in fig. 4, when the cover 50 is covered on the telescopic opening 12, a joint between the outer surface of the cover 50 and the outer surface of the outer tub 10 is in a smooth transition, so that the cover 50 is covered on the rear side 10 of the outer tub to improve the appearance integrity of the mini fan and improve the visual effect. Meanwhile, the user does not feel concave-convex when holding the joint of the cover body 50 and the outer cylinder 10, so that the user can feel better. In combination with the embodiment in which the covering surface abuts against the end surface of the outer cylinder 10, after the cover 50 is covered on the telescopic opening 12, the peripheral wall of the cover 50 is flush with the peripheral wall of the outer cylinder 10, so that the edge of the cover 50 is prevented from being hooked to pull out the main body, and the storage stability of the mini fan is further improved.

In one embodiment, as shown in fig. 4 and 5, the driving device 30 is rotatably mounted to the inner housing 20 such that the output shaft 31 has an inclined position, and in the inclined position, the output shaft 31 is disposed at an angle to the extending and retracting direction of the inner housing 20. The driving device 30 is rotatably connected to the inner casing 20 through a second rotating shaft, and the extending direction of the second rotating shaft is perpendicular to the opening direction of the telescopic opening 12, so that the driving device 30 can rotate to the telescopic direction of the output shaft 31 and the inner casing 20 to form an included angle, the fan direction of the fan blade assembly 40 can form an included angle with the telescopic direction of the inner casing 20, and a user can conveniently face the fan direction to a human body.

Specifically, the mini fan may further include a protective shell 70, the driving device 30 is installed in the protective shell 70, and the protective shell 70 is rotatably connected to the inner shell 20 through a second rotating shaft, so that both the hidden protection of the driving device 30 and the integral rotation of the driving device 30 can be realized. The tip of inner shell 20 can be opened and is established keeping away groove 21, and the cell wall that keeps away groove 21 is the concave cambered surface setting, and the one end that protective housing 70 is close to inner shell 20 is the convex cambered surface setting and cooperates with keeping away groove 21, so, both can guarantee that protective housing 70 can rotate smoothly, reducible protective housing 70 and inner shell 20's total length size again to reduce mini fan's overall length. In combination with the above-mentioned embodiment of the limiting groove 51, the limiting groove 51 can prevent the driving device 30 from rotating due to the acting force acting on the cover 50, so as to prevent the cover 50 from being driven by the driving device 30 to deviate from the expansion opening 12, thereby ensuring that the cover 50 can be stably covered on the expansion opening 12.

In one embodiment, as shown in fig. 7, a sliding groove 13 is formed in an inner wall surface of the outer cylinder 10, the sliding groove 13 extends along an opening direction of the expansion opening 12, a sliding protrusion 22 is protruded on an outer wall surface of the inner shell 20, and the sliding protrusion 22 is slidably engaged with the sliding groove 13. The sliding protrusion 22 slides along the sliding groove 13, and can prevent the inner shell 20 from rotating relative to the outer cylinder 10 when the cross sections of the inner shell 20 and the outer cylinder 10 are both circular, so as to regulate the moving track of the main body. The sliding protrusion 22 has enough matching friction force with the sliding slot 13, so that the sliding protrusion 22 can be positioned at any position of the sliding slot 13 without being subjected to enough pushing and pulling force, thereby ensuring that the fan blade assembly 40 can be stably positioned at the first position. A sliding protrusion 22 may be provided at an end of the inner housing 20 away from the driving device 30 to extend the size of the extendable opening 12 of the inner housing 20. The number of the sliding grooves 13 can be two and are respectively arranged at two opposite positions of the inner wall surface of the outer cylinder 10, and the number and the positions of the sliding protrusions 22 correspond to those of the sliding grooves 13, so that the stress load of a single sliding protrusion 22 can be reduced, and the matching stability of the inner shell 20 and the outer cylinder 10 is further improved.

The above is only the optional embodiment of the present invention, and not the scope of the present invention is limited thereby, all the equivalent structure changes made by the contents of the specification and the drawings are utilized under the inventive concept of the present invention, or the direct/indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A mini fan, comprising:

2. The mini fan as claimed in claim 1, further comprising a handle, wherein the handle is connected to a side of the cover facing away from the receiving cavity.

3. The mini fan as claimed in claim 1 or 2, wherein the cover is fixedly engaged with the output shaft of the driving device to rotate synchronously with the output shaft, and the fan assembly is connected to the cover.

4. The mini fan as claimed in claim 1 or 2, wherein the cover is disposed in a plate shape, and when the cover is disposed on the telescopic opening, the end surface of the outer cylinder abuts against a surface of the cover facing the accommodating chamber.

5. The mini fan as claimed in claim 4, wherein a surface of the cover facing the receiving cavity is recessed with a limiting groove, the limiting groove extends along a peripheral edge of the cover, and when the cover is covered on the telescopic opening, an end of the outer cylinder is in abutting engagement with the limiting groove.

6. The mini fan as claimed in claim 4, wherein when the cover is covered on the telescopic opening, the joint between the outer surface of the cover and the outer surface of the outer cylinder is in a smooth transition.

7. The mini fan as claimed in claim 3, wherein the fan assembly comprises a plurality of fan blades distributed along the circumference of the output shaft, the fan blades being rotatably connected to the cover body to have an expanded state in which the free ends thereof are away from the output shaft and a collapsed state in which the free ends thereof are close to the output shaft.

8. The mini fan of claim 7, wherein the fan blades are configured as soft rubber fan blades.

9. The mini fan as claimed in claim 1, wherein the driving unit is rotatably installed to the inner case such that the output shaft has an inclined position in which the output shaft is disposed at an angle to a telescopic direction of the inner case.

10. The mini fan as claimed in claim 1, wherein a sliding groove is formed on an inner wall surface of the outer casing, the sliding groove extends in an opening direction of the expansion opening, and a sliding protrusion is protruded on an outer wall surface of the inner casing, and the sliding protrusion is slidably engaged with the sliding groove.