Hair dryer

Abstract

The application discloses a blower, and relates to the field of garden tools, which comprises: an air duct part extending in the longitudinal direction, the air duct part being provided with an axial air inlet and an axial air outlet which are communicated with the outside respectively; a fan and a power device arranged in the air duct part; a holding part for a user to hold and operate; an extension rod, the air duct part and the holding part being connected to two ends of the extension rod; an air inlet shroud arranged at the axial air inlet; the pipe diameter of the axial air inlet is between 80 mm and 120 mm, the air inlet shroud comprises a first shroud with a first opening and a second shroud with a second opening for airflow to pass through, the distance between any point on the outer contour of the first opening and any other point on the outer contour of the first opening is not greater than 5 mm, and the anti-deformation capacity of the second shroud is stronger than that of the first shroud. The application can guarantee sufficient air inlet area and effectively block sundries under the premise of high rotating speed and small size.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of garden tools, in particular to a blower. BACKGROUND

[0002] Some existing electric tools are used in environments with a lot of dust or metal debris, which can easily affect the use of the electric tools. For example, tools such as angle grinders, sanders, and garden tools such as blowers. As an example, a blower is a garden tool that can be operated by a user to blow away grass clippings, leaves, and the like to clean a yard or garden.

[0003] A conventional blower generally includes a housing, a holding portion connected to the housing, a blowing pipe connected to one end of the housing, a fan and a motor arranged in the housing, and a safety guard arranged at the other end of the housing. The safety guard can prevent foreign matter from entering the housing and damaging the fan. The motor of this type of blower has a low speed, and the volume of the housing excluding the blowing pipe is large. Therefore, the area of the safety guard can be large, and the safety guard can be made of plastic. The strength of the safety guard can be increased by increasing the thickness of the air inlet grille ribs, which can ensure sufficient air inlet area.

[0004] However, the current trend is to miniaturize the overall structure of the blower. Therefore, a small motor and fan with high speed are required, and the area of the safety guard will be greatly reduced. Therefore, under the condition of a small safety guard area, the existing safety guard cannot ensure sufficient air inlet area and effectively block small foreign matter by simply increasing the thickness of the air inlet grille ribs. SUMMARY

[0005] To overcome the above-mentioned defects of the prior art, the technical problem to be solved by the embodiments of the present application is to provide a blower that can ensure sufficient air inlet area and effectively block foreign matter under the condition of high speed and small size.

[0006] The specific technical scheme of the embodiments of the present application is as follows:

[0007] A blower, comprising:

[0008] a wind tunnel portion extending in a longitudinal direction, the wind tunnel portion having an axial air inlet and an axial air outlet that communicate with the outside, respectively;

[0009] a fan arranged in the wind tunnel portion and a motor in transmission connection with the fan;

[0010] a holding portion for a user to hold;

[0011] an extension rod, the air duct part and the holding part are connected at two ends of the extension rod;

[0012] an air inlet shroud arranged at the axial air inlet;

[0013] the pipe diameter of the axial air inlet is between 80mm and 120mm, the air inlet shroud comprises a first shroud with a first opening for air flow and a second shroud with a second opening, the distance between any point on the outer contour of the first opening and any other point on the outer contour of the first opening is not greater than 5mm, and the second shroud has a stronger deformation resistance than the first shroud.

[0014] Preferably, the first shroud is made of a first material that ensures that the first shroud has a hollow rate greater than or equal to 50% and less than or equal to 80%;

[0015] The second shroud is made of a second material that makes the second shroud as a whole not deformed under the impact of 1 joule.

[0016] Preferably, the first shroud is made of metal wire, nylon or polyester material, and the first shroud comprises a rib surrounding the first opening, and the diameter of the rib is between 0.2mm and 0.7mm.

[0017] Preferably, the second shroud is formed by plastic injection, and the distance between any point on the outer contour of the second opening and any other point on the outer contour of the second opening is greater than 5mm.

[0018] Preferably, the second shroud is located upstream of the first shroud when the air flow passes through the axial air inlet.

[0019] Preferably, the second shroud is connected to the air duct part, and the first shroud is clamped between the second shroud and the air duct part; or

[0020] The second shroud is connected to the air duct part, and the first shroud is fixedly installed with the second shroud.

[0021] Preferably, the ratio of the length of the air duct part in the longitudinal direction to the length of the whole hair dryer in the longitudinal direction is less than or equal to 60%.

[0022] A hair dryer, comprising:

[0023] an air duct part extending in the longitudinal direction, the air duct part having an axial air inlet and an axial air outlet respectively communicating with the outside;

[0024] a fan and a power device arranged in the air duct part, the power device comprising a motor in transmission connection with the fan;

[0025] A holding part for a user to operate;

[0026] An extension rod, the air duct part and the holding part are connected at two ends of the extension rod;

[0027] A first shroud is arranged at the axial air inlet, and a first opening is arranged on the first shroud;

[0028] The pipe diameter of the axial air inlet is between 80mm and 120mm, and the distance between any point on the outer contour of the first opening and any other point on the outer contour of the first opening is not greater than 5mm.

[0029] Preferably, the first shroud comprises a rib arranged to form the first opening, and the strength of the rib and the connection strength between the ribs are such that the first shroud as a whole will not be deformed under an impact of 1 joule.

[0030] Preferably, the first shroud has a hollow rate of greater than or equal to 50% and less than or equal to 80%.

[0031] Preferably, the first shroud is made of a metal material and has a metal mesh structure.

[0032] Preferably, the ratio of the length of the air duct part in the longitudinal direction to the length of the hair dryer in the longitudinal direction is less than or equal to 60%.

[0033] The technical scheme of the present application has the following remarkable beneficial effects:

[0034] The present application sets the air inlet shroud as a first shroud and a second shroud, the distance between any point on the outer contour of the first opening of the first shroud hole and any other point on the outer contour of the first opening is not greater than 5mm, and the anti-deformation ability of the second shroud is stronger than that of the first shroud, so that the second shroud can ensure sufficient strength to support and form a skeleton, and the first shroud does not need to consider high strength at all, it only needs to have a first opening that meets the requirements to effectively block small-sized debris, so the first shroud basically does not need to consider the thickness of the rib forming the first opening, so it can realize small aperture while realizing high hollow rate, thereby providing sufficient air inlet area under the premise of limited pipe diameter of the axial air inlet.

[0035] The particular embodiments of the application described herein are illustrative examples of the principles of the application. Other embodiments could be devised without departing from the spirit of the application. Accordingly, the scope of the application is not intended to be limited to the particular embodiments described. The drawings are for purposes of illustration only and are not intended to be limiting, in terms of shape, layout, or scale of the parts, of the application. The dimensions of the parts shown in the drawings are chosen for convenience of illustration only and are not intended to limit the scope of the application. Various changes could be made to the application described herein by one skilled in the art and which are intended to be within the scope of the application. The features of one embodiment can be used in one or more other embodiments, either alone or in combination with other features, or in place of other features. The features of one embodiment can be used in combination with features of another embodiment, or in place of features of another embodiment. BRIEF DESCRIPTION OF DRAWINGS

[0036] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the application in any way. Additionally, the shapes and relative sizes of the components in the drawings are merely intended to facilitate understanding of the concepts of the application and are not necessarily meant to be limiting in any way. Those skilled in the art will recognize that the application can be practiced with a variety of shapes and relative sizes of the components.

[0037] Figure 1 is a schematic view of a hair dryer according to an embodiment of the application in a first embodiment;

[0038] Figure 2 is a schematic view of a hair dryer according to an embodiment of the application in a second embodiment;

[0039] Figure 3 is a schematic view of a second shroud according to an embodiment of the application in a first embodiment;

[0040] Figure 4 is a schematic view of a second shroud and a first shroud according to an embodiment of the application in a second embodiment;

[0041] Figure 5 is a schematic view of a first shroud sandwiched between the second shroud and the air duct portion. DETAILED DESCRIPTION

[0042] The specific embodiments of the present application described herein are presented by way of example to teach those skilled in the art that best mode of practicing the application. Other embodiments of the application are contemplated. The detailed description of the application is not intended to state in form or substance precisely each and every embodiment of the application covered by the application. The application is capable of other embodiments and of being practiced or being carried out in various ways. As such, the particular embodiments of the present application described herein are not intended to limit the scope of the application but rather the true scope of the present application is indicated by the appended claims. It will be understood that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. In addition, it will be understood that when an element is referred to as being "connected, " it can be directly connected to other element or intervening elements can also be present. The term "and / or" includes combinations thereof.

[0043] Unless otherwise defined, 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 application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this description, the terms "may" and "can" include one or more instances of the occurring feature and the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0044] Figure 1 An example of a power tool is shown, which includes a main housing; a work component performing a work, which work component can be accommodated in the main housing or supported by the main housing; a power device; and a drive device for driving the work component to move. In the present embodiment, the power tool can be a garden blower, a garden blower-suction machine, an angle grinder, an electric hammer, an electric drill, etc. Obviously, the above-mentioned tools are usually used as hand-held work machines. Of course, for those skilled in the art, the above-mentioned power tools can also be designed as a backpack power tool or a waist-hung power tool or a multi-operation mode power tool in some configuration scenarios. For example, a hand-held, backpack two-in-one power tool, a backpack, waist-hung two-in-one power tool, a hand-held, backpack, waist-hung three-in-one power tool.

[0045] As a specific embodiment, the electric tool takes the garden blower 200 as an example, and the embodiment mainly introduces the application of the above-mentioned high-power, small-size, small-diameter high-speed motor 103 to the garden blower 200 as an example. Among them, the high-speed motor 103 is applied in the garden blower 200 to form different garden blower structures, and the same reference signs are adopted in the application. Please refer to Figure 1 and Figure 2 The schematic garden blower 200 can concentrate scattered foreign matters, which can be understood as leaves and garbage. In the application, in order to facilitate understanding, the direction of the airflow flowing out of the axial air inlet is defined as the front (distal end), the side corresponding to the airflow flowing into the axial air outlet is defined as the rear (proximal end), the upper side of the drawing is defined as the upper side, and the lower side of the drawing is defined as the lower side. The left side of the drawing is defined as the left side, and the right side of the drawing is defined as the right side. The above definitions are only for illustration and cannot be understood as a limitation on the application.

[0046] Specifically, as shown in Figure 5 The garden blower 200 extends longitudinally between the proximal end (rear) and the distal end (front). The garden blower 200 includes a main housing, the above-mentioned high-speed motor 103 and a working part. The main housing includes an air duct part 206 extending in the longitudinal direction (the direction shown by the arrow A), a holding part 207 for a user to hold, and an air inlet shroud 208 connected with the air duct part 206. The working part of the garden blower 200 is a fan 202 arranged in the air duct part 206. The high-speed motor 103 is connected with the fan 202 and drives the fan 202 to rotate, so that the fan 202 rotates around a fan axis, thereby driving air to form a moving airflow. It should be noted that the "proximal end" of the application should be understood as the end close to the user when the user uses the garden blower 200 for cleaning work; the "distal end" of the application is understood as the end far away from the user in the longitudinal direction.

[0047] The air duct part 206 is a hollow tubular body, and axial air inlets 2061 and axial air outlets 2062 communicating with the outside are respectively arranged at opposite ends thereof. It can be understood that the hollow means that air can flow smoothly between the axial air inlets 2061 and the axial air outlets 2062. Please refer to Figure 1 As shown in the figure, the air duct part 206 includes a main blowing pipe 2063 extending in the longitudinal direction. The number of the main blowing pipe 2063 can be one and only one; of course, the main blowing pipe 2063 can also be two or more pipe bodies combined to form a blowing pipe with complete blowing function. The two or more pipe bodies can be integrally formed and fixed, or can be fixedly connected through fixing elements.

[0048] The air inlet shroud 208 is connected with the axial air inlet 2061 of the air duct part 206. Specifically, in order to facilitate cleaning of the air duct part 206, the air inlet shroud 208 is detachably connected with the axial air inlet 2061. Of course, the air inlet shroud 208 can also be fixedly connected with the axial air inlet 2061, which can be understood as being integrally formed or being limited by a fixing element. The high-speed motor 103 can drive the axial flow fan 202 to rotate to introduce external air into the air duct part 2063 through the air inlet shroud 208. An air flow channel 2069 for air flow is formed between the air inlet shroud 208 and the axial air outlet 2062.

[0049] For handheld appliances, the user will experience arm fatigue after a long time of holding. This phenomenon is more obvious for handheld appliances that are operated by one hand. As known by those skilled in the art, the garden blower 200 is usually operated by one hand. In order to reduce the fatigue of the user during operation and to achieve lightweight of the garden blower 200, the weight of each component needs to be reduced as much as possible.

[0050] The main cleaning conditions encountered by the garden blower 200 include fallen leaves and small garbage on the ground outside the home or in the park, debris between the joints of the ground tiles, and wet leaves adhered to the ground. After investigation, in order to meet the cleaning requirements of the above conditions, the garden blower 200 usually provides an air volume of not less than 300 CFM and an air speed of not less than 130 MPH. For the garden blower 200 powered by the battery pack 105 of the present application, one embodiment is as follows: Figure 1 and Figure 2The host shell 201 is provided with one or two or more battery pack mounting portions 204 for the combination of the battery pack 105, and the battery pack 105 is mounted on the battery pack mounting portion 204 to supply power to the garden blower 200. When driving a power tool with large output power, the battery pack cannot supply the normal operation power of the garden blower, or the running time of the battery pack 105 is too short to maintain the normal one-time work of the garden blower 200. However, by increasing the weight of a single battery pack, for example, increasing the number of battery cells, on the one hand, the total weight of the garden blower 200 is increased, and on the other hand, the size of the garden blower 200 is also increased, which is not convenient for users to use. Therefore, it is more suitable to use a backpack equipment for power supply. That is, in this case, the battery pack 105 can be configured as a portable battery pack that can be attached to the user's clothes or belt or supported by the user's body. The garden blower 200 is also provided with a battery pack mounting portion (not shown) that can directly combine the battery pack 105. The garden blower 200 can also be configured as a device that can work independently without relying on the power supply of the backpack battery pack 1050. That is, in the preferred embodiment, the battery pack 105 can be combined with the backpack device 1051 to supply power to the garden blower 200, and can also be directly combined with the garden blower 200 to supply power to the garden blower 200. That is, one garden blower 200 can have two use modes, the first mode: backpack mode, which supplies power to the garden blower 200 through the backpack battery pack 1050. Since the backpack battery pack 1050 can connect multiple battery packs or a single large-capacity battery pack as needed, this use mode can support large output power for heavy-duty cleaning, such as cleaning wet leaves, grass, and thick leaf piles. The second mode: handheld mode, which can support light-duty work by adjusting the motor speed. Here, light-duty can be understood as cleaning debris and relatively small amount of leaves. In the case of a small diameter and light weight of the high-speed motor 103 applied to the garden blower 200, in order to achieve the light weight of the whole machine, the outer diameter of the tube body (the region of the air duct portion 206 corresponding to the high-speed motor 103) around the high-speed motor 103 is small, and the outer diameter of the axial inlet 2061 of the air duct portion 206 is also small, that is, the air duct portion 206 is thin, so the tube diameter of the axial inlet 2061 of the air duct portion 206 is controlled to be between 80mm and 120mm.

[0051] In order to meet the requirements of light weight and blowing effect, the present application provides a new type of garden blower 200 air duct portion 206 design, which is only configured at the front end of the garden blower 200, and is closer to the ground than the holding portion 207. The ratio of the length of the air duct portion 206 in the longitudinal direction to the length of the whole garden blower 200 in the longitudinal direction is less than or equal to 60%, the air duct of the blower is short, and the axial inlet is closer to the ground. For details, please refer toFigure 2 The garden blower 200 includes an elongated rod 209 extending longitudinally between a proximal end and a distal end. The air duct portion 206 is supported at the distal end of the elongated rod 209, the handle portion 207 is supported at the proximal end of the elongated rod 209, and the handle portion 207 and the air duct portion 206 are spaced apart from each other and pulled away from each other by a distance between the proximal end and the distal end, so that the axial air inlet 2061 is closer to the foreign matter than the handle portion 207 when the user holds the garden blower 200 for operation. When the operator holds the garden blower 200 for operation, the high-speed motor 103, the axial air inlet 2061, the axial flow fan 202, and the axial air outlet 2062 are all located below the handle portion 207. In this way, the length of the air duct portion 206 is shortened.

[0052] As shown in Figure 1 and Figure 2 , the elongated rod 209 is a long tubular structure that at least partially passes through the air inlet shroud 208. The width of the elongated rod 209 in the left-right direction is less than the width of the air inlet shroud 208 in the left-right direction. In this way, the thinner elongated rod 209 further supports the lightweight requirement.

[0053] For the close type (axial air inlet close to the ground) garden blower 200 in this embodiment, most of the weight units are concentrated at the front end, which can improve the comfort of the user's operation.

[0054] Please refer to Figure 1 and Figure 2 , in a possible implementation, the air inlet shroud 208 is installed outside the axial air inlet 2061. First, for the close type garden blower 200, its axial air inlet 2061 is relatively close to the foreign matter on the ground. When the user uses the machine for cleaning operation, debris and fallen leaves are easily lifted. The high-speed rotating axial flow fan 202 can bring small hard objects (such as small stones) into the air duct portion 206 together with the air. These hard objects can hit the outer surface of the axial flow fan 202, damaging the axial flow fan 202, and thus affecting the blowing effect.

[0055] Applicant conducted fan 202 impact stone or other hard object test for the case that the hard object might hit the outer surface of the axial fan 202 and damage the axial fan 202: in the test, the fan was rotated at a set speed, and stones or other hard objects of different sizes were thrown into the fan 202 in the air duct part 206, to test whether the stones or other hard objects would damage the fan 202, so as to determine the maximum size of the stone or other hard object that the strength of the fan 202 of the hair dryer 200 could withstand. The maximum stone size or other hard object size is the maximum value of the hair dryer safety guard aperture. Generally speaking, the greater the speed of the fan 202, the more likely the fan is to be damaged under the condition that the size of the stone or other hard object is the same. Therefore, under the premise of high speed of the hair dryer, the air inlet guard 208 of the hair dryer has the need for small aperture. Further, due to small volume, the volume of the fan 202 is small, the blades of the fan 202 are thin, and the overall strength is weakened, further making the fan easy to be damaged, and the need for small aperture is more urgent.

[0056] In the test process, various types of hair dryers under common voltages of 20V, 40V and 80V were tested respectively. For the hair dryer under the power supply of the 20V battery pack, the speed of the high-speed motor is between 25000RPM and 50000RPM, and at the speed of 25000RPM, the size of the stone that damages the fan 202 is greater than or equal to about 5mm, and the size of the other hard object that damages the fan 202 is greater than or equal to about 8mm, and such hard objects have a density and hardness lower than that of stones, such as small wooden sticks, branches, etc. At the speed of 30000RPM, the size of the stone that damages the fan 202 is greater than or equal to about 4mm, and the size of the other hard object that damages the fan 202 is greater than or equal to about 7mm. For the hair dryer under the power supply of the 40V battery pack 105, the speed of the high-speed motor is between 27000RPM and 33000RPM, and at the speed of 33000RPM, the size of the stone that damages the fan 202 is greater than or equal to about 3.7mm, and the size of the other hard object that damages the fan 202 is greater than or equal to about 6.6mm. For the hair dryer under the power supply of the 80V battery pack 105, the speed of the high-speed motor is between 41000RPM and 50000RPM, and at the speed of 41000RPM, the size of the stone that damages the fan 202 is greater than or equal to about 3mm, and at the speed of 50000RPM, the size of the stone that damages the fan 202 is greater than or equal to about 1mm.

[0057] Since the garden blower must provide the minimum air volume, air speed as mentioned above when meeting the cleaning requirements, and the axial air inlet 2061 of the air duct part 206 is reduced to between 80mm and 120mm due to the miniaturization of the garden blower, the open area of the air inlet guard needs to be considered to ensure sufficient air inlet area and the possibility of dropping stones. The maximum distance of the opening on the air inlet guard is not greater than 5mm, so that the debris that can damage the fan 202 can be basically intercepted or blocked. Since the pipe diameter of the axial air inlet 2061 is between 80mm and 120mm, the area of the axial air inlet is small, and the open area of the air inlet guard needs to be greater than or equal to 50% and less than or equal to 80% to ensure that the air inlet guard has a required air inlet area.

[0058] In order to make the air inlet guard block the debris, it must also have a certain strength to avoid damage or breakage under the impact of the debris. It is easy to understand that under the condition of a certain surface area of the air inlet guard 208, the more openings 2081 on the air inlet guard 208, the larger the surface area occupied by the solid structure constituting the openings 2081. The air inlet guard 208 not only needs to ensure that small objects cannot enter the air duct part 206, but also needs to ensure the air inlet volume. Moreover, the garden blower 200 provided by the present application applies a high-speed motor 103, which can drive more air into the air duct part 206 in the same time. And the continuous air supply is easy to push the airflow in the air duct part 206 to flow forward quickly, reduce airflow loss, and improve air speed. In this case, the air inlet guard 208 needs to provide sufficient air inlet area to match the performance.

[0059] In a possible implementation, the air inlet guard 208 can include a first guard 208b arranged at the axial air inlet 2061, and the first guard 208b has a first opening formed by regular geometric bodies or irregular geometric bodies. Figure 3 As shown, the air inlet guard 208 can include a second guard 208a arranged at the axial air inlet 2061, and the second guard 208a has a second opening formed by regular geometric bodies or irregular geometric bodies.

[0060] The distance between any point on the outer contour of the first opening and any other point on the outer contour of the first opening is not greater than 5 mm, so that the first shroud 208b can basically intercept or block the sundries that can cause damage to the fan 202. The distance between any point on the outer contour of the second opening and any other point on the outer contour of the second opening can be greater than 5 mm. The deformation resistance of the second shroud is greater than that of the first shroud. The second shroud 208a mainly plays a role of supporting and forming a skeleton, and of course it can also block sundries of large size from entering the air duct part 206. The first shroud 208b mainly plays a role of blocking sundries of small size from entering the air duct, thereby avoiding damage to the fan 202 caused by the impact of the sundries. Of course, the size of the second opening is not limited, and the distance between any point on the outer contour of the second opening and any other point on the outer contour of the second opening can be much greater than 5 mm. When the airflow passes through the axial air inlet 2061, the second shroud 208a is located upstream of the first shroud 208b, so that the second shroud 208a can preferentially block large-size sundries, thereby avoiding that the impact force of the large-size sundries is too large and directly impacts on the first shroud 208b, which can cause damage to the first shroud 208b. At the same time, it can also avoid that the user directly touches the first shroud 208b, thereby causing damage to the first shroud 208b.

[0061] In a feasible implementation, the second shroud 208a can be a grid with a second opening, the grid having ribs, and the ribs and the ribs therebetween forming the second opening. The second shroud is made of a second material, which can be plastic, metal material, etc., and can be formed by injection molding, lathe processing, etc. If the second shroud 208a needs to be able to block sundries of small size from entering the air duct, the ribs need to be thin and the second opening needs to be small, which can cause insufficient strength of the second shroud 208a, so that the second shroud 208a cannot play a role of supporting and forming a skeleton. Moreover, making the second opening small can greatly reduce the porosity of the second shroud 208a. Since the cross-sectional area of the axial air inlet 2061 is limited, the air inlet shroud cannot have a required air inlet area. Considering that the main role of the second shroud 208a is to support and form a skeleton, the second opening can be much larger than the first opening, so that the ribs of the second shroud 208a can be thick to ensure sufficient strength, so that the strength of the second shroud 208a is greater than that of the first shroud 208b. In order to ensure that the second shroud 208a can play a role, the second shroud as a whole needs to be able to withstand an impact of 1 joule without deformation.

[0062] Specifically, the first protective cover can be made of metal wire, nylon, polyester, etc. The first protective cover includes ribs that form a plurality of first openings, and the diameter of the ribs is between 0.2mm and 0.7mm. The ribs of the first protective cover 208b are thin, and although the strength of the first protective cover 208b is much smaller than that of the second protective cover 208a, the first protective cover 208b can effectively improve the porosity of the first protective cover 208b, and the strength thereof only needs to be able to block the impact of small-size sundries. When the first protective cover 208b is made of metal wire, the first protective cover 208b can be understood as a metal mesh woven by metal wire.

[0063] In the above embodiment, the second protective cover 208a can be connected with the air duct portion 206. The first protective cover 208b can be installed on the inner side of the second protective cover 208a, i.e., the side close to the fan 202, and the two are fixedly installed and tightly attached together. As shown in Figure 4 The first protective cover 208b can be tightly attached to the second protective cover 208a, for example, the second protective cover 208a can be directly combined with the first protective cover 208b during injection molding, of course, the first protective cover 208b can also be combined with the second protective cover 208a by hot riveting or ultrasonic welding, etc. In other feasible embodiments, as shown in Figure 5 The second protective cover 208a is connected with the air duct portion 206, and the first protective cover 208b is clamped between the second protective cover 208a and the air duct portion 206.

[0064] When the air duct portion 206 is thin and the cross-sectional area of the axial air outlet 2062 is relatively small, the demand for light weight can be naturally met, but the air volume will also be reduced to a certain extent. For this purpose, as shown in Figures 1 to 2 The air duct portion 206 further includes an auxiliary blowing pipe 2066 in fluid communication with the main blowing pipe 2063. The main blowing pipe 2063 and the auxiliary blowing pipe 2066 have a gap 2060 therebetween, so that external air can enter the auxiliary blowing pipe 2066 through the gap.

[0065] In addition, when the first protective cover 208b meets the condition of not being easily deformed, the hair dryer can only be provided with the first protective cover 208b, and the strength of the ribs and the connection strength between the ribs are such that the first protective cover 208b as a whole will not be deformed under the impact of 1 joule.

[0066] In another embodiment, the air inlet shroud 208 is circumferentially surrounded outside the axial air inlet 2061, and the air inlet shroud 208 is provided with a plurality of shroud holes 2081 on its outer surface, which are internally and externally hollowed out to allow air flow therethrough, and the shroud holes 2081 are formed by regular geometric shapes or irregular geometric shapes, each geometric shape comprising at least two opposite edges 2082, 2083. First, for the close-range garden blower 200, its axial air inlet 2061 is relatively close to foreign matter on the ground. When the user uses the machine for cleaning work, debris and fallen leaves are easily lifted. The high-speed rotating axial flow fan 202 can bring small hard objects (such as small stones) into the air duct 206 together with the air. These hard objects can hit the outer surface of the axial flow fan 202, damaging the axial flow fan 202, thereby also affecting the blowing effect.

[0067] In the present embodiment, please refer to Figure 3 , the maximum aperture of the shroud hole is not greater than 4 mm, or it is understood that the maximum distance between the two opposite edges is not greater than 4 mm, preferably, the maximum aperture of the shroud hole is not greater than 3 mm. Small gaps make smaller hard objects also cannot enter into the air duct 206. The maximum cross-sectional area of the shroud hole 2081 is greater than or equal to 3 mm 2 , and less than or equal to 13 mm 2 . The cross-sectional area here refers to the projection of the shroud hole on the fan rotation plane. The maximum cross-sectional area of the shroud hole 2081 can be 4 mm 2 , 5 mm 2 , 6 mm 2 , 7 mm 2 , 8 mm 2 , 9 mm 2 . Preferably, the maximum cross-sectional area of the shroud hole 2081 is greater than or equal to 4 mm 2 , and less than or equal to 6 mm 2 .

[0068] It is easy to understand that, under the condition of a certain surface area of the air inlet shroud 208, the more the shroud holes 2081 are, the larger the surface area occupied by the solid structure constituting the shroud holes 2081 is. The air inlet shroud 208 not only needs to ensure that objects with a small volume cannot enter the air duct part 206, but also needs to ensure the air inlet volume. Moreover, the garden blower 200 provided by the present application uses a high-speed motor 103, which can directly drive an axial flow fan to bring more air into the air duct part 206 in the same time. The continuous supply of air facilitates the rapid forward flow of the air flow in the air duct part 206, reduces air flow loss, and improves wind speed. In this case, the air inlet shroud 208 needs to provide sufficient air inlet area to match this performance. In the present embodiment, the air flow channel 2069 includes a surrounding area surrounding the high-speed motor 103 and a transition area between the surrounding area and the fan 202. Air enters the surrounding area from the shroud holes 2081 of the air inlet shroud 208, and then contacts the fan 202 through the transition area. In order to provide sufficient air inlet volume, the minimum area S1 of the longitudinal air passing area of the surrounding area is designed to be greater than the area of the rotating surface formed by the rotation of the blades 2022 of the fan 202, and the minimum area S2 of the longitudinal air passing area of the transition area is designed to be greater than the area of the rotating surface formed by the rotation of the blades 2022 of the fan 202. Specifically, the minimum area S2 of the longitudinal air passing area of the transition area is not less than 2900mm 2 .

[0069] In the present embodiment, the extension distance of the air inlet shroud 208 in the extension direction of the fan axis is not less than 45mm, the configuration that the air speed blown out of the axial air outlet connected to the air inlet shroud and the garden blower is not less than 130mph, and the air volume is not less than 300cfm limits the rotation speed of the high-speed motor 103 to be greater than 35000rpm and less than or equal to 80000rpm. Preferably, the extension distance of the air inlet shroud 208 in the extension direction of the fan axis X1 is not less than 50mm, the configuration that the air speed blown out of the axial air outlet 2062 connected to the air inlet shroud 208 and the garden blower 200 is not less than 150mph, and the air volume is not less than 340cfm limits the rotation speed of the high-speed motor 103 to be greater than or equal to 45000rpm and less than 80000rpm.

[0070] In detail, the air inlet shroud 208 includes a shroud one 2080 connected to the axial air inlet 2061. The shroud one 2080 is generally cylindrical. The shroud one 2080 extends a predetermined distance in the extension direction of the fan axis X1 and allows external air to enter the air duct part 206 along the radial direction of the fan axis.

[0071] As Figure 1As shown, the extension rod 209 is an elongated tubular structure that at least partially passes through the air inlet shroud 208. The width of the extension rod 209 in the left-right direction is smaller than the width of the air inlet shroud 208 in the left-right direction. This design, with its thinner extension rod 209, further supports the requirement for lightweight construction. The air inlet shroud 208 also includes a second shroud 2084, which is coaxially arranged with the extension rod 209. The second shroud 2084 is closer to the proximal end than the first shroud 2080, and its center protrudes towards the rear end of the extension rod 209, thus forming a partially spherical structure to allow outside air to enter the air duct section longitudinally.

[0072] This application combines two different protective covers to enable the air inlet cover 208 to introduce air both longitudinally and radially. Furthermore, the optimized design of the cover hole 2081 reduces the risk of hard objects entering the air duct section 206.

[0073] Secondly, because the axial air inlet 2061 is close to the ground, when the user holds the garden hair dryer 200, some debris or fallen leaves may adhere to the surface of the air inlet cover 208 as the air moves, causing blockage and affecting the blowing effect of the garden hair dryer 200. In this embodiment, as... Figure 3As shown, the air inlet area of the shroud one 2080 is larger than the air inlet area of the shroud two 2084. Since the shroud hole 2081 of the shroud two 2084 is directly opposite to the axial fan 202, the air inlet direction of the shroud hole 2081 of the shroud two 2084 is substantially along the extension direction of the fan axis X1. Therefore, when the axial fan 202 rotates, the outside air flows into the air duct 206 along the extension direction of the fan axis X1, the air flow loss is small, the air flow speed is fast, and thus a large pressure difference is formed in the front end of the shroud two 2084. Therefore, the fallen leaves and debris lifted by the air flow flow forward quickly, and the large leaves are sucked to the surface of the shroud hole 2081 of the shroud two 2084 by the strong air flow. Since the shroud hole 2081 of the shroud one 2080 is not directly opposite to the axial fan 202, firstly, the air flow flowing into the air duct 206 from the shroud hole 2081 of the shroud one 2080 is smaller than the air flow flowing into the air duct 206 from the shroud hole 2081 of the shroud two 2084, and the pressure difference between the front end of the shroud two 2084 and the outside is larger than the pressure difference between the front end of the shroud one 2080 and the outside. Therefore, the air flow flowing to the front end of the shroud one 2080 is smaller than the air flow flowing to the front end of the shroud two 2084. Furthermore, the shear force acting on the fallen leaves and debris is relatively small, which is perpendicular to the fan axis. According to a large number of simulation experiments, the shear force is substantially smaller than the gravity of the large-sized foreign matters (the small-sized foreign matters directly flow into the air duct with the air flow, and thus the shroud hole 2081 is not blocked).

[0074] All articles and references disclosed above, including patents and publications, are incorporated by reference for all purposes. The term "consisting essentially of to describe a combination shall include the elements, ingredients, components or steps identified, and such other elements ingredients, components or steps that do not materially affect the basic and novel characteristics of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, ingredients, components or steps herein also is taken to mean that "comprising" or "including" such elements, ingredients, components or steps is optional. The use of the term "may" to describe any aspect of this disclosure is intended to mean that such aspect is optional. Multiple elements, ingredients, components or steps can be provided by a single integrated element, ingredient, component or step. Alternatively, a single integrated element, ingredient, component or step might be divided into separate multiple elements, ingredients, components or steps. To "comprise" or "include" an element or list of elements having "one" does not exclude the existence of additional elements that are the same as said element or one of the list of elements or additional different elements.

[0075] The various embodiments in the specification are described in progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between embodiments can be mutually referred to. The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A hair dryer characterized by, The hair dryer comprises: a wind channel part extending in a longitudinal direction, the wind channel part having an axial air inlet and an axial air outlet respectively communicating with the outside; a fan and a motor drivingly connected with the fan arranged in the wind channel part; a holding part for a user to hold and operate; an extension rod, the wind channel part and the holding part being connected at two ends of the extension rod; an air inlet shroud arranged at the axial air inlet; a pipe diameter of the axial air inlet is between 80mm and 120mm, the air inlet shroud comprises a first shroud having a first opening for airflow to pass through and a second shroud having a second opening, a distance between any point on an outer contour of the first opening and any other point on the outer contour of the first opening is not greater than 5mm, the second shroud has a stronger deformation resistance than the first shroud; the second shroud is connected with the wind channel part, and the first shroud is clamped between the second shroud and the wind channel part; or the second shroud is connected with the wind channel part, and the first shroud is fixedly installed with the second shroud; the first shroud is arranged between the second shroud and the wind channel part.

2. The hair dryer of claim 1, wherein the first shroud is made of a first material, the first material ensures that the first shroud has a hollow rate greater than or equal to 50% and less than or equal to 80%; the second shroud is made of a second material, the second material makes the second shroud as a whole not deformed under an impact of 1 joule.

3. The hair dryer of claim 1, wherein the first shroud is made of a metal wire, nylon or polyester material, the first shroud comprises a rib surrounding to form the first opening, a diameter of the rib is between 0.2mm and 0.7mm.

4. The hair dryer of claim 1, wherein the second shroud is formed by plastic injection, a distance between any point on an outer contour of the second opening and any other point on the outer contour of the second opening is greater than 5mm.

5. The hair dryer of claim 1, wherein the second shroud is located upstream of the first shroud when airflow passes through the axial air inlet.

6. The hair dryer of claim 1, wherein a ratio of a length of the wind channel part in a longitudinal direction to a length of the whole hair dryer in the longitudinal direction is less than or equal to 60%.

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