The present disclosure relates to the technical field of garden tools, and more specifically, relates to a garden tool with a blowing function.
With the continuous expansion of urban green areas, green belts in public places such as parks and roads have spread across the country, and garden tools with a blowing function have been widely applied. For example, a garden blower is a common type of garden tool with a blowing function, which utilizes airflow blown to the ground to remove dust or debris to facilitate cleaning. In order to generate higher air pressure and air speed to satisfy cleaning requirements, the garden blower is required to operate at higher power to produce desired wind power, which is likely to produce noise as a result.
However, the quality of the structural design of the garden tools directly determines the level of noise during operation. For example, in the existing garden tools, due to structure cooperation defects between fans, high levels of noise may be generated when the airflow passes through gaps between the fans.
In the existing garden tools, stationary vanes with certain rectifying effects on the airflow are often structurally designed with a forward tilt towards an air inlet side, causing the noise of the airflow still to be high.
In the existing garden tools, in order to optimize the air inlet effect, an air intake shield is arranged at the air inlet side. However, the noise reduction effect is not significant due to design defects of a grid structure on the air intake shield.
On that basis, it is necessary to provide a garden tool with a blowing function, which can effectively reduce noise during operation while ensuring blowing performance.
A garden tool with a blowing function includes: a housing; a blowing tube, connected with the housing and air may be blown out from the blowing tube; a fan, rotating around a fan axis for making air flow; and a motor, configured for driving the fan to rotate around the fan axis. When the motor operates at a maximum rotational speed, blowing force F and noise LP of the garden tool with a blowing function satisfy the following relationships: 16 N≤F≤23 N, and 53 dBA≤LP<57 dBA; or, 23 N<F≤40 N, and 53 dBA≤LP≤0.0121F2−0.0603F+53.065 dBA.
In one of embodiments, the rotational speed of the motor is 16000 r/min to 26000 r/min.
In one of embodiments, the rotational speed of the motor is 18000 r/min to 22000 r/min.
In one of embodiments, a diameter of a projection profile of the fan in a plane perpendicular to the fan axis is 88 mm to 120 mm.
In one of embodiments, when the motor operates at the maximum rotational speed, the blowing force F and the noise LP of the garden tool with a blowing function further satisfy following relationships:
23 N<F≤40 N, and 53 dBA≤LP≤0.0081F2+0.1374F+48.473 dBA.
In one of embodiments, an air volume Q, pressure Ppressure, and input power Ppower of the motor of the garden tool with a blowing function respectively satisfy following relationships:
450 cfm≤Q≤1500 cfm, 1400 Pa≤Ppressure≤5000 Pa, and 700 W≤Ppower≤3000 W.
In one of embodiments, the garden tool is a blower for blowing leaves on the ground. The housing is provided with an air inlet. The blower includes an air intake shield connected to the air inlet. The fan is configured to rotate around the fan axis and introduce external air through the air intake shield. The fan includes: a hub; and a plurality of fan blades extending outwards from the hub in a radial direction and distributed around the fan axis. The fan blade includes a pressure surface configured for generating airflow, and a suction surface. The pressure surface and the suction surface intersect in the direction of the fan axis to form a front edge and a rear edge, and the front edge is located in front of the rear edge in a rotating direction of the fan.
In the direction of the fan axis, a minimum distance between the front edge of the fan blade of the fan and the air intake shield is D5, and a length of the garden tool is L0; wherein 0.15≤D5:L0≤0.4.
In one of embodiments, the blower further includes a duct connected with the housing. The duct includes an outer guide cover, an inner guide cover, and first stationary vanes connected between the outer guide cover and the inner guide cover, and the motor is accommodated in the inner guide cover. A ratio of a cross sectional area S1 of the air inlet to a cross sectional area S2 of the outer guide cover is 1.6 to 4.
According to the above garden tool with a blowing function, the motor drives the fan to rotate around its axis, such that the air is blown out from the blowing tube. The garden tool in one of embodiments shows different noise reduction effects under different working conditions. When the blowing force of the garden tool is greater than or equal to 16 N and less than or equal to 23 N, in other words, the garden tool is applied to medium working conditions, the generated noise is controlled at 53 dBA≤LP<57 dBA; and when the blowing force of the garden tool is greater than 23 N and less than or equal to 40 N, in other words, the garden tool is applied to heavy working conditions, the generated noise is controlled at 53 dBA≤LP≤0.0121F2−0.0603F+53.065 dBA. Accordingly, the garden tool in one of embodiments effectively reduces the noise during operation while ensuring the blowing performance.
One of embodiments provides a garden tool with a blowing function, which includes: a housing; a blowing tube, connected with the housing, and air may be blown out from the blowing tube; a fan, rotating around a fan axis for making air flow, the fan includes: a hub and a plurality of fan blades extending outwards from the hub in a radial direction and distributed around the fan axis; and a motor, configured for driving the fan to rotate around the fan axis. Wherein the fan blade includes a pressure surface configured for generating airflow, and a suction surface; the pressure surface and the suction surface intersect in the direction of the fan axis to form a front edge and a rear edge; in a rotating direction of the fan, the front edge is located in front of the rear edge, and projections of the adjacent front edges and rear edges of two adjacent fan blades do not overlap in a plane perpendicular to the fan axis; and an interval gap is provided between projections of the two adjacent fan blades in the plane perpendicular to the fan axis, and the interval gap D0 is greater than 0 mm and less than or equal to 4 mm.
In one of embodiments, the interval gap D0 is greater than or equal to 2 mm and less than or equal to 3.5 mm.
In one of embodiments, the fan axis is defined as an X-axis, a line passing through one end point of the front edge close to the hub and perpendicular to and intersected with the fan axis is defined as a Y-axis, and a line perpendicular to and intersected with the X-axis and the Y-axis is defined as a Z-axis. A maximum distance between projections of the suction surface and the pressure surface in a plane formed by the X-axis and the Z-axis is defined as a maximum thickness h of the fan blade.
A ratio of a value of the interval gap D0 to a value of the maximum thickness h of the fan blade ranges from 1 to 1.5.
In one of embodiments, the number of the fan blades is 7 to 23.
In one of embodiments, the fan blades are formed on the hub through injection molding or die casting.
In one of embodiments, a ratio of a diameter D2 of the hub to a diameter D1 of projection profiles of all the fan blades in a plane perpendicular to the fan axis is 0.4 to 0.6.
One of embodiments provides a garden tool with a blowing function, which includes: a housing; a blowing tube, connected with the housing and provided with an air outlet for air to be blown out; a fan, rotating around a fan axis and configured for making air flow and blow the air out from the air outlet; and a motor, configured for driving the fan to rotate around the fan axis.
The fan includes: a hub and a plurality of fan blades extending outwards from the hub in a radial direction and distributed around the fan axis. The fan blade includes a root portion fixed to the hub, a top edge spaced from the hub, and a front edge and a rear edge extending between the root portion and the top edge, and in a rotating direction of the fan, the front edge is located in front of the rear edge.
The fan axis is defined as an X-axis, a line passing through the end point of the front edge close to the hub and perpendicular to and intersected with the fan axis is defined as a Y-axis, and a line perpendicular to and intersected with the X-axis and the Y-axis is defined as a Z-axis.
Midpoints of projections of the root portion and the top edge in a plane formed by the X-axis and the Y-axis are correspondingly defined as a first midpoint and a second midpoint; a line passing through the first midpoint and parallel to the Y-axis is defined as a first vertical axis, and in an airflow flowing direction, the second midpoint is located on a downstream side of the first vertical axis facing the air outlet of the blowing tube.
In one of embodiments, an included angle β between a line connecting the first midpoint and the second midpoint and the first vertical axis is 0° to 9°.
In one of embodiments, a projection of the front edge in a plane formed by the Y-axis and the Z-axis is defined as a front side projection, and a line connecting two opposite end points of the front side projection is defined as a chord line L.
At least two positions of the front side projection are respectively located on two opposite sides of the chord line L.
In one of embodiments, the front side projection at an outer profile of a part of the front edge away from the hub deviates from the chord line L, and the part of the front edge away from the hub is concave away from one side of the blowing tube with the air outlet.
The front side projection at an outer profile of a part of the front edge close to the hub deviates from the chord line L, and the part of the front edge close to the hub is convex towards the side of the blowing tube with the air outlet.
In one of embodiments, the projection of the front edge in a plane formed by the Y-axis and the Z-axis is defined as the front side projection. The front side projection bends and extends at the outer profile of a part of the front edge away from the hub, such that a concave structure is formed on the front side projection, and an opening orientation of the concave structure and the rotating direction of the fan are kept consistent.
In one of embodiments, a bending angle α between a tangent line, at an intersection that is point of the outer profiles of the front edge and the top edge and that is away from the hub, of the front side projection, and the chord line L is 5° to 15°.
In one of embodiments, the projection of the front edge in the plane formed by the X-axis and the Y-axis is located on one side of the Y-axis towards the air outlet of the blowing tube.
In one of embodiments, an included angle θ between the Y-axis and a tangent line, at the end point of the front edge close to the hub, of the projection of the front edge in the plane formed by the X-axis and the Y-axis is 3° to 25°.
In one of embodiments, a line passing through one end point of the rear edge close to the hub and perpendicular to the X-axis is defined as a second vertical axis.
The projection of the rear edge in the plane formed by the X-axis and the Y-axis is located on one side of the second vertical axis facing away from the air outlet of the blowing tube.
In one of embodiments, an included angle δ between a tangent line, at an intersection point of the rear edge and the hub, of the projection of the rear edge in the plane formed by the X-axis and the Y-axis, and the second vertical axis is 8° to 20°.
In one of embodiments, the fan is sectioned by a plane perpendicular to the Y-axis, a line connecting intersection points between the section and the front edge and the rear edge is defined as an installation line, and an installation included angle γ between the installation line and the X-axis is gradually increased from the root portion to the top edge.
In one of embodiments, the installation included angle γ between the installation line and the X-axis is 5° to 30° at the root portion.
In one of embodiments, the included angle γ between the installation line on the top edge and the X-axis is 30° to 85° at the top edge.
In one of embodiments, the fan blade further includes a curved surface transition portion located at a junction of the rear edge and the top edge and approaching the hub from the top edge, and an arc surface of the curved surface transition portion is convex away from the hub.
In one of embodiments, a corner radius of a projection of the curved surface transition portion in the plane formed by the X-axis and the Y-axis is 1 mm to 5 mm.
In one of embodiments, an included angle η between the Y-axis and a tangent line, at one end point of the curved surface transition portion close to the top edge, of the projection of the curved surface transition portion in the plane formed by the X-axis and the Y-axis is 0° to 45°.
In one of embodiments, a duct connected with the housing is further included. The duct includes an outer guide cover, an inner guide cover, and first stationary vanes connected between the outer guide cover and the inner guide cover. A gap D3 between projections of the fan blade and the first stationary vane in the plane formed by the X-axis and the Y-axis is gradually enlarged from the root portion to the top edge.
One of embodiments provides a garden tool with a blowing function, which includes: a housing; a blowing tube, connected with the housing and provided with an air outlet for air to be blown out; a duct, connected to the housing and configured for guiding the air to flow; a fan, rotating around a fan axis to make the air flow; and a motor, configured for driving the fan to rotate around the fan axis. The duct includes an outer guide cover, an inner guide cover, and first stationary vanes connected between the outer guide cover and the inner guide cover.
The first stationary vane includes a bottom connected to the inner guide cover, a top connected to the outer guide cover, and a first front side edge and a first rear side edge located in an airflow flowing direction in a spaced manner.
The fan axis is defined as an X-axis, and a plane passing through any point on the fan and perpendicular to the X-axis is defined as a reference plane.
A distance between one end point of the first front side edge close to the bottom and the reference plane is less than a distance between one end point of the first front side edge close to the top and the reference plane.
In one of embodiments, the fan includes: a hub and a plurality of fan blades extending outwards from the hub in a radial direction and distributed around the fan axis. The fan blade includes a root portion fixed to the hub, a top edge spaced from the hub, and a front edge and a rear edge extending between the root portion and the top edge, and in a rotating direction of the fan, the front edge is located in front of the rear edge.
A distance between the end point of the first front side edge close to the bottom and one end point of the rear edge close to the root portion is less than a distance between the end point of the first front side edge close to the top and one end point of the rear edge close to the top edge.
In one of embodiments, a distance between one end point of the first rear side edge close to the bottom and the reference plane is less than a distance between one end point of the first rear side edge close to the top and the reference plane.
In one of embodiments, the fan includes: a hub and a plurality of fan blades extending outwards from the hub in a radial direction and distributed around the fan axis. The fan blade includes a root portion fixed to the hub, a top edge spaced from the hub, and a front edge and a rear edge extending between the root portion and the top edge, and in a rotating direction of the fan, the front edge is located in front of the rear edge.
A distance between the end point of the first rear side edge close to the bottom and one end point of the rear edge close to the root portion is less than a distance between the end point of the first rear side edge close to the top and one end point of the rear edge close to the top edge.
In one of embodiments, an axis of the inner guide cover is defined as an X′-axis, a line passing through the end point of the first front side edge close to the bottom and perpendicular to and intersected with the X′-axis is defined as a Y′-axis, and a line perpendicular to and intersected with the X′-axis and the Y′-axis is defined as a Z′-axis.
A part, close to the fan, of a stationary vane section obtained by sectioning the first stationary vane by a surface parallel to a plane formed by the X′-axis and the Z′-axis, crosses the X′-axis, and bends and extends in a circumferential direction of the inner guide cover.
In one of embodiments, a maximum height, in the direction of the Z′-axis, of the stationary vane section obtained by sectioning the first stationary vane by the surface parallel to the plane formed by the X′-axis and the Z′-axis is defined as a bending distance D4 of the first stationary vane.
The bending distance D4 of the first stationary vane is gradually increased from the bottom to the top.
In one of embodiments, the bending distance D4 of the first stationary vane is 1 mm to 15 mm.
In one of embodiments, the first stationary vane has a windward side and a leeward side opposite to the windward side. Outer profiles of projections of the windward side and the leeward side in the plane formed by the X′-axis and the Z′-axis intersect, and an included angle between a tangent line at an intersection point close to the fan and the X′-axis is defined as a first stationary vane inlet angle Le, where the first stationary vane inlet angle Le is 35° to 65°.
In one of embodiments, the stationary vane section includes a first part extending along the X′-axis, and a second part crossing the X′-axis, and bending and extending in the circumferential direction of the inner guide cover. The second part includes a concave line and a convex line which are oppositely arranged, a maximum distance between a line connecting two ends of the concave line and the convex line is defined as a concave chord height H, and the concave chord height H is 2 mm to 6 mm.
In one of embodiments, the projection of the first front side edge in the plane formed by the X′-axis and the Y′-axis is located on one side of the Y-axis towards the air outlet of the blowing tube.
In one of embodiments, an included angle ε between a tangent line at a position, close to the bottom, of the projection of the first front side edge in the plane formed by the X′-axis and the Y′-axis, and the X′-axis is 60° to 90°.
In one of embodiments, the projection of the first rear side edge in the plane formed by the X′-axis and the Y′-axis is an arc concave towards the first front side edge.
In one of embodiments, an included angle b between a tangent line at a position, close to the bottom, of the projection of the first rear side edge in the plane formed by the X′-axis and the Y′-axis, and the X′-axis is 45° to 90°.
In one of embodiments, an included angle c between a tangent line at a position, close to the top, of the projection of the first rear side edge in the plane formed by the X′-axis and the Y′-axis, and the X′-axis is smaller than the included angle b.
In one of embodiments, the bottom of the first stationary vane is inclined at a first angle relative to the fan axis; and the top of the first stationary vane is inclined at a second angle relative to the fan axis.
In one of embodiments, the first stationary vanes are distributed around the inner guide cover at equal intervals, and airflow generated by the fan can pass through gaps between the first stationary vanes; and the number of the first stationary vanes is 3 to 11.
In one of embodiments, a length of the first stationary vane is L1, a mid-arc line chord length of the fan blade of the fan is L2, and 3≤L1:L2≤9.
The length of the first stationary vane is defined as a distance between the first front side edge of the first stationary vane and the first rear side edge of the first stationary vane in the airflow flowing direction.
One of embodiments provides a garden tool with a blowing function, which includes: a housing; a blowing tube, connected with the housing, and air may be blown out from the blowing tube; a duct, connected to the housing and configured for guiding the air to flow; a fan, rotating around a fan axis to make the air flow; and a motor, configured for driving the fan to rotate around the fan axis. The duct includes an outer guide cover, an inner guide cover, and first stationary vanes connected between the outer guide cover and the inner guide cover. The garden tool further includes a guide cone connected to the inner guide cover, and second stationary vanes arranged on the guide cone.
The second stationary vanes are located downstream of the first stationary vanes in the airflow flowing direction.
In one of embodiments, the second stationary vane includes a first inner side edge connected to the guide cone, a first outer side edge opposite to the first inner side edge and connected with the first inner side edge, and an intersection point located at a joint of the first inner side edge and the first outer side edge. The first outer side edge is in an arc shape convex outwards in the radial direction.
In one of embodiments, a width W of the second stationary vane is linearly reduced from the first inner side edge to the first outer side edge.
In one of embodiments, the second stationary vane includes two tail end parts respectively adjacent to the corresponding intersection points, and a middle part located between the two tail end parts. A width of the middle part at the same cross section is kept unchanged, and a width of the tail end parts at the same cross section is gradually increased from the intersection points to the middle part.
In one of embodiments, the second stationary vanes are arranged around the guide cone at equal intervals, and airflow flowing through the first stationary vanes can pass through gaps between the second stationary vanes; and the number of the second stationary vanes is 3 to 7.
In one of embodiments, a length of the second stationary vane is L3, a chord length of the first stationary vane is L4, and 0.2≤L3:L4≤1.
The length of the second stationary vane is defined as the size of the second stationary vane in the airflow flowing direction.
In one of embodiments, an inlet installation angle of the second stationary vane is d, and 0°≤d≤15°.
The inlet installation angle of the second stationary vane is defined as an included angle between a tangent line at a mid-arc surface of the second stationary vane and the fan axis of the fan.
In one of embodiments, the garden tool further includes third stationary vanes located downstream of the second stationary vanes in the airflow flowing direction. The third stationary vanes are in a flat plate shape, roughly extend in the direction of the fan axis, and are arranged at equal intervals in the circumferential direction.
In one of embodiments, the number of the third stationary vanes is 3 to 11.
In one of embodiments, a distance between the third stationary vane and the first stationary vane is L5, the chord length of the first stationary vane is L4, and 2≤L5:L4≤4.
In one of embodiments, a length of the third stationary vane is L6, the chord length of the first stationary vane is L4, and 0.5≤L6:L4≤2. The length of the third stationary vane is defined as the size of the third stationary vane in the direction of the fan axis.
In one of embodiments, an inlet installation angle of the third stationary vane is e, and 0°≤e≤15°.
In one of embodiments, the third stationary vane includes a second front side edge, a second rear side edge, a second inner side edge close to the housing, and a second outer side edge opposite to the second inner side edge.
The second outer side edge expands and obliquely extends relative to the fan axis in the airflow flowing direction, and the second front side edge concavely bends and extends relative to the fan axis, and is in smooth transition with the second outer side edge.
One of embodiments further provides a garden tool with a blowing function, which includes: a housing; a blowing tube, connected with the housing, and air may be blown out from the blowing tube; a duct, connected to the housing and configured for guiding the air to flow; a fan, rotating around a fan axis to make the air flow; and a motor, configured for driving the fan to rotate around the fan axis. The duct includes an outer guide cover, an inner guide cover, and first stationary vanes located between the outer guide cover and the inner guide cover. The garden tool further includes third stationary vanes located downstream of the first stationary vanes in the airflow direction.
In one of embodiments, the third stationary vanes are arranged in a connected region of the housing and the blowing tube.
In one of embodiments, the third stationary vanes are in a flat plate shape, roughly extend in the direction of the fan axis, and are arranged at equal intervals in the circumferential direction.
In one of embodiments, the duct further includes a guide cone connected to the inner guide cover, and second stationary vanes arranged on the guide cone.
The second stationary vanes are located between the first stationary vanes and the third stationary vanes in the airflow flowing direction.
One of embodiments provides a garden tool with a blowing function, which includes: a housing, provided with an air inlet; a fan, rotating around a fan axis for making air flow; a motor, configured for driving the fan to rotate around the fan axis; and an air intake shield, connected to the air inlet. The fan is configured to rotate around the fan axis and introduce, by the air intake shield, external air from the air inlet. The air intake shield includes a three-dimensional air inlet array grid with an outward convex outer envelope surface. The three-dimensional air inlet array grid includes:
In one of embodiments, the plurality of grid units are arranged into a plurality of rows at intervals in the second direction, and the grid units in each row are arranged in the first direction.
The two most adjacent grid units in adjacent rows are staggered in the first direction.
In one of embodiments, two adjacent flow-breaking ribs in adjacent rows are staggered at equal intervals in the first direction.
In one of embodiments, the three-dimensional air inlet array grid has a main air inlet region and auxiliary air inlet regions surrounding the main air inlet region; and projections of the grid units located in the main air inlet region in the plane perpendicular to the axis of the air inlet are the same in shape.
In one of embodiments, the flow-breaking rib includes a first air guide portion and a second air guide portion, wherein the first air guide portion and the second air guide portion extend towards the adjacent spaced webs from the ejection portion. The flow-breaking rib has a windward side and a leeward side opposite to the windward side.
A preset distance D6 of the leeward side of the ejection portion protruding outward relative to the web is 2 mm to 20 mm.
In one of embodiments, the ejection portion has a top surface on the windward side, and the first air guide portion and the second air guide portion are respectively a first air guide surface and a second air guide surface on the windward side.
A width of the top surface is respectively smaller than a width of the first air guide surface and the second air guide surface.
In one of embodiments, the width of the first air guide surface and the second air guide surface is gradually increased from their joints with the top surface to the web direction.
In one of embodiments, the top surface is perpendicular to the axis of the air inlet.
Included angles between projections of the first air guide surface and the second air guide surface in the plane perpendicular to the first direction and a projection of the top surface in the plane perpendicular to the first direction are both De, where 90°≤De≤180°.
In one of embodiments, the windward side further includes third air guide surfaces located on two opposite sides of the flow-breaking rib in the first direction.
The third air guide surfaces are connected to the top surface, the first air guide surface, and the second air guide surface, and obliquely extend outwards in the first direction.
In one of embodiments, an included angle between the first air guide surfaces on two opposite sides of the top surface is 10° to 60°.
In one of embodiments, a distance between two adjacent webs is 5 mm to 15 mm.
In one of embodiments, one side surface of the web facing away from intake air in the first direction at least includes a first surface and a second surface intersected with each other, and an included angle between the first surface and the second surface is 140° to 180°.
In one of embodiments, the air intake shield further includes a frame connected to the air inlet, and the frame surrounds outside the three-dimensional air inlet array grid.
In one of embodiments, the outer envelope surface of the three-dimensional air inlet array grid protrudes out of one end surface of the frame facing away from the air inlet.
In one of embodiments, the air intake shield has a shield axis, and one end surface of the frame facing away from the air inlet inclines relative to the shield axis.
One of embodiments provides a garden tool with a blowing function, which includes: a housing, provided with an air inlet; a fan, rotating around a fan axis to make air flow; a motor, configured for driving the fan to rotate around the fan axis; and an air intake shield, connected to the air inlet. The fan can rotate around the fan axis and introduce, by the air intake shield, external air from the air inlet.
The garden tool further includes a plurality of guide vanes arranged at an upstream region of the fan, and the airflow introduced from the air inlet may pass through gaps between the guide vanes, so as to be guided into parallel airflow.
In one of embodiments, the plurality of guide vanes are arranged in parallel at equal intervals.
In one of embodiments, a distance between two adjacent guide vanes is 12 mm to 18 mm.
In one of embodiments, a distance between the guide vanes and the air inlet is 10 mm to 50 mm
In one of embodiments, a chord length of each guide vane is 10 mm to 50 mm.
In one of embodiments, the housing has an airflow channel communicated with the air inlet.
The housing includes a straight section roughly parallel to the fan axis, and a bending section located upstream of the straight section and downwards bending relative to the straight section.
The guide vanes are arranged at the bending section and extend along an inner wall of the bending section.
In one of embodiments, an included angle between the fan axis and a vertical line perpendicular to a plane where the air inlet is located is 120° to 180°.
In one of embodiments, the housing includes a first half housing and a second half housing which are symmetrically arranged relative to a symmetric reference plane. The fan axis is located on the symmetric reference plane, and the first half housing and the second half housing are provided with matched upper edges and lower edges. Projections of parts, located on the bending section, of the upper edge of the first half housing and the upper edge of the second half housing, towards the symmetric reference plane are overlapped and have a third curved profile.
Projections of parts, located on the bending section, of the lower edge of the first half housing and the lower edge of the second half housing towards the symmetric reference plane are overlapped and have a fourth curved profile.
In one of embodiments, both the third curved profile and the fourth curved profile are in an arc shape.
The third curved profile and the fourth curved profile are located on concentric circles with different radiuses.
In one of embodiments, the guide vane includes a first sub-guide vane and a second sub-guide vane symmetrically arranged relative to the symmetric reference plane.
The first sub-guide vane and the second sub-guide vane are coupled to form the complete guide vane.
In one of embodiments, projections of the guide vanes towards the symmetric reference plane have a fifth curved profile; and the fifth curved profile is of an arc shape.
Mid-arc lines equally dividing the third curved profile and the fourth curved profile are perpendicular to and equally divide the fifth curved profile.
The drawings constituting a part of this application are used for providing a further understanding of the present disclosure. The exemplary embodiments of the present disclosure and descriptions thereof are used for explaining the present disclosure, and do not constitute improper limitations on the present disclosure.
In order to describe the technical solutions in the embodiments of the present disclosure more clearly, the accompanying drawings required for describing the embodiments are briefly introduced below. Apparently, the accompanying drawings in the following description show some embodiments of the present disclosure, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.
To make the above objectives, features, and advantages of the present disclosure more apparent and understandable, specific implementations of the present disclosure will be described in detail below in conjunction with the accompanying drawings. Many specific details are described below to facilitate a thorough understanding of the present disclosure. However, the present disclosure can be implemented in many other ways different from those described herein. Those skilled in the art may make similar improvements without departing from the intention of the present disclosure. Therefore, the present disclosure is not limited to the specific embodiments disclosed below.
An electric tool with a blowing function in the related prior art specifically may be a garden tool 100, such as a garden blower, which typically includes a housing 10, a duct 30, a fan 50 for generating airflow, a motor configured for driving the fan 50, and a blowing tube 20 adaptively connected to the housing 10. In this implementation, the motor and the fan 50 are both arranged in the duct 30; the duct 30 is arranged in the housing 10; and the blowing tube 20 is connected with the housing 10 to form an airflow channel with the housing 10. The blowing tube 20 is provided with an air outlet 22; the housing 10 is further provided with an air inlet 11; the duct 30 is configured for guiding airflow generated by the fan 50 to move towards the air outlet 22 of the blowing tube 20; and the air enters the housing 10 from the air inlet 11 and flows through the airflow channel to the air outlet 22 to be blown out. Of course, the duct may also be connected between the housing 10 and the blowing tube 20.
The high working performance and low noise of the above garden blower are contradictory to each other. Specifically, the cleaning conditions that the garden blower encounters mainly include: fallen leaves and small debris on outdoor or park grounds, debris between pavement brick joints, and wet leaves adhering to the ground. The inventors found through researches that in order to satisfy the cleaning requirements for the above working conditions, the garden blower usually needs to provide a sufficiently large air volume and air speed. However, for example, the motor and the fan 50 are downsized, the rotational speed of the motor is required to be increased so as to ensure the air volume and the air speed, and as a result, noise produced when the airflow impacts fan blades 54 and generates vortex is increased; and meanwhile, the size of the duct 30 is reduced, which may also increase the noise caused when the airflow impacts an internal structure of the duct 30 and generates vortex. In addition, when the airflow separates from the vortex, high-decibel noise, and even high-pitched noise are likely to be produced.
Thus, the trade-off between high working performance and low noise has always been a challenge and constraint for manufacturers. In one of embodiments, improvements are made on structures such as an air intake shield, the fan, and stationary vanes in the duct 30, which avoid the generation of the vortex when the airflow impacts the internal structure of the duct 30, so as to achieve downsizing and low noise while the blowing performance is kept basically unchanged.
One of embodiments illustrates, by taking the garden blower as an example, the structure of the garden tool 100 with a blowing function in this application. Specifically, the garden tool 100 may be a handheld garden blower. This embodiment is provided only as an illustrative example and does not limit the scope of the technology of one of embodiments.
In some embodiments, referring to
According to the above garden tool 100 with a blowing function, the motor drives the fan 50 to rotate around its axis, such that the air is blown out from the blowing tube 20. The garden tool 100 in one of embodiments shows different noise reduction effects under different working conditions. When the blowing force of the garden tool 100 is greater than or equal to 16 N and less than or equal to 23 N, in other words, the garden tool 100 is usually applied to medium working conditions, the generated noise can be controlled at 53 dBA≤LP<57 dBA; and when the blowing force of the garden tool 100 is greater than 23 N and less than or equal to 40 N, in other words, the garden tool 100 is usually applied to heavy working conditions, the generated noise can be controlled at 53 dBA≤LP≤0.0121F2−0.0603F+53.065 dBA. Accordingly, the garden tool 100 in one of embodiments effectively reduces the noise during operation while ensuring the blowing performance.
It should be noted that the blowing force in this embodiment may be of a value between 16 N and 23 N in the medium working conditions, such as 16 N, 17 N, 18 N, 19 N, 20 N, 21 N, and 22 N, and the noise can be controlled to be greater than or equal to 53 dBA and less than 57 dBA, such as 53 dBA, 54 dBA, 55 dBA, and 56 dBA. Similarly, the blowing force is of a value greater than 23 N under the heavy working conditions, such as 24 N, 25 N, 27 N, 29 N, 30 N, 35 N, and 40 N, and the noise in one of embodiments may be of a value between 53 dBA and 0.0121F2−0.0603F+53.065 dBA, such as 53 dBA, 54 dBA, 55 dBA, 56 dBA, 58 dBA, 60 dBA, 62 dBA, 63 dBA, 64 dBA, and 65 dBA. In this embodiment, the acquisition of the blowing force requires the garden tool 100 to be at a maximum rotational speed, in other words, a maximum blowing force value acquired when the garden tool 100 operates at the maximum rotational speed, and the noise is measured under the maximum rotational speed.
More preferably, when the blowing force of the garden tool 100 is greater than 23 N and less than or equal to 40 N, the blowing force F and the noise LP satisfy following relationships: 23 N<F≤40 N, and 53 dBA≤LP≤0.0081F2+0.1374F+48.473 dBA.
It should be noted that the blowing force is of a value greater than 23 N under the heavy working conditions, such as 24 N, 25 N, 27 N, 29 N, 30 N, 35 N, and 40 N, and the noise in one of embodiments may be of a value between 53 dBA and 0.0081F2+0.1374F+48.473 dBA, such as 53 dBA, 54 dBA, 55 dBA, 56 dBA, 58 dBA, 60 dBA, 62 dBA, and 63 dBA.
It should be further noted that noise data recorded in this embodiment may be acquired according to a noise measuring method for the garden tool 100 specified by GB/T4583-2007, and may also be acquired by EU noise regulations, and the like. For example, the requirements for the testing environment may be one of the following: a free-field laboratory above a reflecting surface; an outdoor flat open space where no other reflectors present except for an emitting surface in the testing environment, such that a sound source radiates into a free space above the reflecting surface; and a room where the impact of a reverberant field on the measured surface sound pressure is relatively smaller compared to a sound source emission field. For the criteria for background noise, averaged background noise at the position of a microphone should be at least 6 dBA, and preferably, 15 dBA or above lower than the measured sound pressure level.
Specifically, community background noise less than 52 decibels may be chosen, multiple (e.g., 8) direction points may be selected along a circle with a radius of 15 meters (50 feet), centered on a test personnel to be subject to A-weighted sound pressure level testing, 8 test values are averaged to obtain a noise value, and a test tool may be a handheld sound level meter.
The garden tool 100 in one of embodiments aims to achieve better noise reduction performance, meaning that under the same blowing force, the product has lower noise. The inventors found through researches that improvements are made on at least one of structures such as an upstream region of an air channel portion 12, the fan 50, first stationary vanes 36, second stationary vanes 39, third stationary vanes 40, and an air intake shield 60. For example, arranging a sound-absorbing or sound-insulating material in the upstream region and/or a downstream region of the air channel portion 12, controlling interval gaps between the fan blades 54 of the fan 50, bending front edges 546 of the fan 50 in a rotating direction of the fan 50, and tilting backwards and extending a first front side edge 366 or a second rear side edge 368 of the first stationary vane 36 towards the side of the air outlet 22. The above different improvement structures or different combinations of improvement structures achieve better noise reduction effects.
As below, a noise test is performed on the garden tool 100 with different combinations of two improvement structures to acquire noise data, and referring to Table 1.
Table 1 provides examples of noise data for the garden tool with different combinations of two improvement structures in one of embodiments.
In some specific embodiments, the measured data for noise 1 lies within a diagonally-hatched region below a curve in
Specifically, in one of embodiments, the rotational speed of the motor is controlled to be at 13000 r/min to 27000 r/min. Preferably, the rotational speed of the motor is controlled to be at 16000 r/min to 26000 r/min. When the motor runs, the reduced rotational speed results in decreased noise, however, excessively lowering the rotational speed may lead to a decrease in air volume. Accordingly, the rotational speed of the motor is reasonably controlled in one of embodiments, and is set to be at 16000 r/min to 26000 r/min. To realize a garden tool 100 with a reasonable rotational speed and a low-noise effect, it is necessary to effectively reduce the noise of the garden tool 100 while ensuring a reasonable air outflow volume.
Further, the rotational speed of the motor is controlled to be at 18000 r/min to 22000 r/min. Accordingly, the rotational speed of the motor is further limited within a certain range, such that the garden tool 100 can better balance the air outflow volume and the noise lowering volume, thereby enhancing the use experience of the product.
It should be noted that the rotational speed of the motor is any value within 16000 r/min to 26000 r/min. For example, the rotational speed of the motor may be but not limited to 18000 r/min, 18500 r/min, 19000 r/min, 19500 r/min, 20000 r/min, 22000 r/min, 23000 r/min, 24000 r/min, 25000 r/min, and the like, and reducing the rotational speed of the motor will result in decrease in generated noise.
In some embodiments, a diameter of a projection profile of the fan 50 in a plane perpendicular to the fan axis 51 is 88 mm to 120 mm. The diameter of the fan 50 has a certain influence on the air outflow volume. As the diameter of the fan 50 increases, the air outflow volume also increases. However, the too large diameter of the fan 50 not only results in an increase in overall size of the garden tool 100, but also requires the motor to output larger power for acting. Accordingly, in order to balance the air outflow volume, the product size, and motor acting of the garden tool 100, the diameter of the fan 50 is reasonably controlled at 88 mm to 120 mm, which not only increases the air outflow volume but also facilitates downsizing and energy conservation of the garden tool 100, thereby realizing the garden tool 100 with a low rotational speed, a high air volume, and a low-noise effect.
It should be noted that the diameter of the projection profile should be understood as: the projection of the fan 50 in the plane perpendicular to the fan axis 51 is or is similar to a circle outline, and the diameter of the circle outline is the diameter of the projection profile. The diameter of the projection profile during design may be selected as but not limited to 88 mm, 90 mm, 95 mm, 100 mm, 105 mm, 110 mm, 115 mm, 120 mm, and the like.
In some embodiments, an air volume Q, pressure Ppressure, and input power Ppower of the motor of the garden tool 100 with a blowing function respectively satisfy the following relationships: 450 cfm≤Q≤1500 cfm, 1400 Pa≤Ppressure≤5000 Pa, and 700 W≤Ppower≤3000 W. According to the formula that air channel efficiency=(air flow rate in the garden tool 100×air outlet pressure at the blowing tube 20)/input power of the motor, data of the air volume Q, the pressure Ppressure, and the input power Ppower of the garden tool 100 are respectively reasonably controlled, so as to ensure high air channel efficiency.
Further, the air volume Q, Ppressure, and input power Ppower of the motor of the garden tool 100 with a blowing function respectively satisfy the following relationships: 600 cfm≤Q≤850 cfm, 3000 Pa≤Ppressure≤4500 Pa, and 700 W≤Ppower≤1400 W. According to the formula that air channel efficiency=(air flow rate in the garden tool 100×air outlet pressure at the blowing tube 20)/input power of the motor, the air channel efficiency of the garden tool 100 is reasonably improved, and the performance of the garden tool 100 is enhanced. The air channel efficiency can be optimized by low noise.
In some embodiments, referring to
It can be inferred that the too small distance between the fan 50 and the air intake shield 60 may result in direct airflow impacting on the fan 50, which in turn increases operating noise. The too large distance between the fan 50 and the air intake shield 60 not only weakens the suction of the fan 50 at the air intake shield 60, but also leads to an overall increase in length of the electric tool, namely the garden tool 100, making the product bulkier. Thus, a ratio of the minimum distance D5 between the fan 50 and the air intake shield 60 to the length L0 of the garden tool 100 is controlled to be within 0.15 to 0.4. For example, the distance between the air inlet 11 and the front edge 546 of the fan blade 54 is about 200 mm, such that there is sufficient space in front of the fan 50, so as to reduce pressure drop in the garden tool 100 and weaken noise amplitude. Accordingly, the reasonable product structure and smooth air inflow can be ensured, and noise can be reduced.
It should be noted that the minimum distance between the front edge 546 of the fan blade 54 of the fan 50 and the air intake shield 60 should be understood as: the distance, in the direction of the fan axis 51, between the front edge 546 of the fan blade 54 and the air intake shield 60 (e.g., a frame 64 or a three-dimensional air inlet array grid) is minimized. The length of the garden tool 100 should be understood as a distance, in the direction of the fan axis 51, between two end points on the outermost side of the garden tool 100, such as a maximum distance, in the direction of the fan axis 51, between one side surface, facing away from the fan 50, of the air intake shield 60 and the end, away from the fan 50, of the blowing tube 20.
Further, referring to
In an embodiment, referring to
According to the above garden tool 100 with a blowing function, the plurality of fan blades 54 are distributed on the hub 52 around the fan axis 51 at intervals, such that the interval gap is provided between the projections of the two adjacent fan blades 54 in the plane perpendicular to the fan axis 51, thereby making the airflow stably pass through the interval gap, and ensuring the blowing efficiency of the garden tool 100. Because the interval gap D0 is controlled to be less than or equal to 4 mm, the gap between two adjacent fan blades 54 is reduced, and as a result, when the garden tool 100 operates, pulsation of frequency-doubled noise generated by the airflow between the two adjacent fan blades 54 can be reduced, thereby effectively reducing operation noise of the garden tool 100. In addition, the number of the fan blades 54 in the fan 50 has a negative correlation with a width of the fan blades 54. In other words, the width of the fan blades 54 can be increased by reducing the number of the fan blades 54, and the width of the fan blades 54 can be reduced by increasing the number of the fan blades 54. However, if the manner of increasing the number of the fan blades 54 to reduce the width of the fan blades 54 is adopted to ensure firmness of the fan blades 54, it inevitably causes changes of surface pressure gradient of the fan blades 54, leading to a decrease in blowing efficiency. Thus, the interval gap D0 in one of embodiments is controlled to be less than or equal to 4 mm, and under the premise of ensuring the number of the fan blades 54, the width of the fan blades 54 in the fan 50 is increased as much as possible, so as to improve the blowing efficiency. In one of embodiments, the number of the fan blades 54 is 7 to 23. Preferably, the number of the fan blades may be 11 to 17. For example, the number of the fan blades may be but not limited to 13, 15, and the like.
In some embodiments, referring to
It should be noted that the interval gap D0 may be any value between 2 mm and 3.5 mm, such as 2 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3 mm, 3.2 mm, 3.4 mm, and 3.5 mm.
In some embodiments, referring to
In some embodiments, the fan blades 54 are formed on the hub 52 through injection molding or die casting. The manufacturing cost can be reduced by integrally forming the fan blades 54 and the hub 52, but when the interval gap between the fan blades 54 is less than 2 mm, the mold manufacturing precision is significantly reduced, meanwhile, the manufacturing difficulty is increased, and thus, the interval gap is preferably greater than or equal to 2 mm. When the interval gap is greater than 3.5 mm, the aerodynamic performance of the fan 50 will be reduced, and on that basis, the interval gap is preferably less than or equal to 4 mm.
It should be noted that the garden tool 100 is configured for performing cleaning work, and may be but not limited to a handheld blower, a knapsack blower, and the like, which can gather scattered debris, and the debris may be leaves or garbage. For ease of understanding, as shown in
It should be further noted that the hub 52 is roughly in a cylinder shape, which has a closed upstream end and an open downstream end. Specifically, the hub 52 includes a center hole 522. The shape and size of the center hole 522 are constructed to accommodate a motor shaft of the motor and/or a rotor. For example, the motor shaft of the motor may be connected to the center hole 522 in an interference fit manner or other transmission connection manners, the plurality of fan blades 54 extend around a circumferential direction of the hub 52, and the fan axis 51 penetrates through a center of the center hole 522. The fan blades 54 and the hub 52 may be integrally formed, thereby reducing the manufacturing cost, and of course, the fan blades 54 and the hub 52 may also be separately manufactured and then assembled together, which is not limited herein.
An end portion of the hub 52 in an airflow incoming direction during rotation of the fan 50 is provided with a flow guide surface configured for guiding the airflow to flow towards the fan blades 54, and the flow guide surface may be partially or fully shaped as an elliptic paraboloid, an elliptic cone, a circular conical surface, and the like, which is not limited herein. Accordingly, the flow guide surface can guide the airflow to generate rotational flow, thereby preventing the airflow from vertically impacting the fan blades 54, so as to reduce the noise.
In addition, interval gaps are provided between the projections of the adjacent front edges 546 and rear edges 548 of two adjacent fan blades 54 in a plane perpendicular to the fan axis 51. Accordingly, the airflow can be guided to enter the area of the duct 30 between the fan blades 54, so as to avoid generation of vortex and reduce the noise. In some embodiments, the interval gap continuously changes from a root portion 542 to a top edge 544. For example, in an embodiment shown in
In the specific embodiment, the projection of the front edge 546 in the plane perpendicular to the fan axis 51 has a first curved profile, the rear edge 548 includes a second curved profile in the projection in the plane perpendicular to the fan axis 51, and a curvature of the first curved profile is different from that of the second curved profile. Accordingly, it can be guaranteed that the interval gap continuously changes from the root portion 542 to the top edge 544.
In some embodiments, referring to
It should be noted that the air channel portion 12 may be a tubular body combination formed by connecting two or more sections of tubular bodies. It is to be understood that the garden tool 100 with a blowing function may also have an air suction function, in other words, air together with debris are sucked in from the air outlet 22 of the blowing tube 20 and then are discharged from the above air inlet 11 after passing through the fan 50.
It should be further noted that the plurality of fan blades 54 are the same in geometric shape, and for the sake of brevity, a single fan blade 54 is adopted for further descriptions below. The fan blade 54 extends outwards roughly in the radial direction of the hub 52, and the hub 52 and the fan blade 54 are driven by the motor to rotate around the above fan axis 51, thereby generating airflow moving in the direction of the fan axis 51. As a preferred implementation, the fan axis 51 penetrates through the center of the hub 52, thereby ensuring that the airflow flowing direction is basically parallel to the extending direction of the fan axis 51 and air channel portion 12 and avoiding noise caused by vortex generated by the airflow. A gap is also provided between the fan blade 54 and an inner wall of the air channel portion 12, which not only can avoid interference between the fan blade 54 and the inner wall of the air channel portion 12, but also avoid the noise caused by the vortex formed between the fan blade 54 and the inner wall of the air channel portion 12. Preferably, the size of the gap in the radial direction is less than 1 mm.
Further, referring to
In some embodiments, a sound-absorbing material is arranged on at least part of the inner wall of the upstream region of the air channel portion 12. Specifically, the damping sound-absorbing material may be foam or fiber-based composite materials, or for example, glass fiber or natural fiber composite materials, or may also be other high polymer materials such as polyurethane foam. The inventors of this application have found that a main source of noise of the garden tool 100 with a blowing function, such as the garden blower, is primarily attributed to the air channel portion 12. Further analysis has revealed that one reason for the noise generation is the unevenness inside the air channel portion 12. After the airflow impacts the inner wall of the air channel portion 12, the vortex is likely to be generated at depressions, leading to noise. Arranging the sound-absorbing material in the upstream region of the air channel portion 12 may be understood as arranging the sound-absorbing material on at least part of the inner wall of the housing between the air inlet 11 and the fan. On one hand, uneven portions inside an air channel cavity are as smooth as much as possible, minimizing the formation of vortex; and on the other hand, the damping sound-absorbing material can absorb the noise, thereby reducing the noise heard by the user, and improving the operation comfort of the user. As a preferred implementation, the sound-absorbing material is sound-insulating sponge. Of course, further, the sound-absorbing material may be arranged downstream of the fan. Specifically, the outer guide cover is wrapped by the sound-absorbing material in the circumferential direction, and/or the sound-absorbing material is arranged downstream of the outer guide cover.
In some embodiments, the pressure surface 543 and the suction surface 545 are respectively two opposite side surfaces of the fan blade 54. When the fan blade 54 rotates, the pressure surface 543 pushes air to flow towards the side of the air outlet 22, such that the air stably passes through the interval gap so as to form stable airflow flowing.
Meanwhile, the projections of the pressure surface 543 and the suction surface 545 in the plane formed by the X-axis and the Z-axis may be linear profiles or surface profiles. For example, when the pressure surface 543 and the suction surface 545 are first-order or higher-order curved surfaces in the direction of the Y-axis (i.e., the radial direction of the hub 52), the projections of the pressure surface 543 and the suction surface 545 in the plane formed by the X-axis and the Z-axis may at least partially overlap, so as to form the surface profiles. In this case, the maximum distance between the projections of the pressure surface 543 and the suction surface 545 may be understood as a length of a line connecting any point on the projection of the pressure surface 543 and a corresponding point on the projection of the suction surface 545. Of course, when the thickness h of the fan 50 is determined, a sectional method may also be adopted. For example, the fan blade 54 is sequentially sectioned from the root portion 542 to the top edge 544 in a plane parallel to the plane formed by the X-axis and the Z-axis. In this case, the pressure surface 543 and the suction surface 545 are respectively linear profiles on corresponding sections; and a maximum distance between the two linear profiles is taken as the thickness h of the fan 50. Alternatively, during verification, measuring tools such as a vernier caliper may also be clamped onto the pressure surface 543 and the suction surface 545 to perform direct measurement.
In some embodiments, referring to
It should be noted that the ratio of the diameter D2 of the hub 52 to the diameter D1 of the projection profiles of all the fan blades 54 in the plane perpendicular to the fan axis 51 may be any value between 0.4 and 0.6. For example, the ratio of the diameter D2 of the hub 52 to the diameter D1 of the projection profiles of all the fan blades 54 in the plane perpendicular to the fan axis 51 is 0.4, 0.45, 0.5, 0.55, 0.6, and the like.
Specifically, the ratio of the diameter D2 of the hub 52 to the diameter D1 of the projection profiles of all the fan blades 54 in the plane perpendicular to the fan axis 51 is 0.5, such that configuration of the wheel-hub 52 ratio of the fan 50 is more reasonable, and the blowing effect is better.
In some embodiments, the fan blade 54 includes the root portion 542 fixed to the hub 52, the top edge 544 spaced from the hub 52, the front edge 546, and the rear edge 548. The root portion 542 is the radial innermost edge of the fan blade 54 closest to the hub 52 and attached to the hub 52, and the top edge 544 is the radial outermost edge of the fan blade 54 spaced from the hub 52. The front edge 546 is the foremost edge in the direction of the airflow passing through the fan 50, and is also an edge of the fan blade 54 with which the airflow firstly makes contact in the rotating process of the fan 50, and the front edge 546 extends between the root portion 542 and the top edge 544. The rear edge 548 is the rearmost edge in the direction of the airflow passing through the fan 50, and is also an edge of the fan blade 54 with which the airflow lastly makes contact in the rotating process of the fan 50, and the rear edge 548 extends between the root portion 542 and the top edge 544. A first end, at the root portion 542, of the front edge 546 is attached to the hub 52; a second end, at the root portion 542, of the front edge 546 is spaced from the hub 52; a first end, at the root portion 542, of the rear edge 548 is attached to the hub 52; and a second end, at the root portion 542, of the rear edge 548 is spaced from the hub 52.
In some embodiments, referring to
According to the above garden tool 100 with a blowing function, the plurality of fan blades 54 are distributed on the hub 52 around the fan axis 51 at intervals, thereby making the airflow stably pass through two adjacent fan blades 54, and ensuring the blowing efficiency of the garden tool 100. The second midpoint 5441 of the top edge 544 is located on one side of the first vertical axis 5422 facing the air outlet 22 of the blowing tube 20, in other words, the second midpoint 5441 does not cross the first vertical axis 5422 along an air inlet side facing the garden tool 100, and thus, the overall top edge 544 tends to extend towards the air outlet 22 relative to the root portion 542. This design ensures better alignment between the shape design of the fan 50 and the airflow direction, reduces collisions between the airflow and the fan blades 54, and increases the length of a path through which the airflow passes, so as to increase the work done by the airflow on surfaces of the fan blades 54, reduce the noise, and improve the blowing efficiency.
It should be noted that the hub 52 is roughly in a cylinder shape, which has a closed upstream end and an open downstream end. The shape of the hub 52 is designed similarly to any above embodiment, which may be directly referred to the above description, and is not specifically described herein.
It should be further noted that the root portion 542 is the radial innermost edge of the fan blade 54 closest to the hub 52 and attached to the hub 52, and the top edge 544 is the radial outermost edge of the fan blade 54 spaced from the hub 52. The front edge 546 is the foremost edge in the direction of the airflow passing through the fan 50, and is also an edge of the fan blade 54 with which the airflow firstly makes contact in the rotating process of the fan 50, and the front edge 546 extends between the root portion 542 and the top edge 544. The rear edge 548 is the rearmost edge in the direction of the airflow passing through the fan 50, and is also an edge of the fan blade 54 with which the airflow lastly makes contact in the rotating process of the fan 50, and the rear edge 548 extends between the root portion 542 and the top edge 544. A first end, at the root portion 542, of the front edge 546 is attached to the hub 52; a second end, at the root portion 542, of the front edge 546 is spaced from the hub 52; a first end, at the root portion 542, of the rear edge 548 is attached to the hub 52; and a second end, at the root portion 542, of the rear edge 548 is spaced from the hub 52.
Further, referring to
Optionally, the included angle β between the line connecting the first midpoint 5421 and the second midpoint 5441 and the first vertical axis 5422 may be but not limited to 1°, 2°, 3°, 5°, 7°, 8°, 9°, and the like. In some specific embodiments, the included angle β between the line connecting the first midpoint 5421 and the second midpoint 5441 and the first vertical axis 5422 is 2°.
In some embodiments, referring to
It should be noted that the projection of the front edge 546 may have two positions respectively located on the two opposite sides of the chord line L 5462, and may also have two positions both located on one side of the chord line L 5462, and one position located on the other side of the chord line L 5462; or, may have two positions both located on one side of the chord line L 5462, and two positions both located on the other side of the chord line L 5462, in other words, the front edge 546 is designed with a quartic curve.
Further, referring to
It should be noted that the front side projection 5461 of the front edge 546 in the plane formed by the Y-axis and the Z-axis has concave and convex deviation design relative to the chord line L 5462, and concavity and convexity may be different in radian and may also be kept consistent. When concavity and convexity at two positions of the front side projection 5461 are kept consistent in radian, the front side projection 5461 has sinusoidal waveform design.
Specifically, referring to
In some specific embodiments, the ratio of the first chord height 5465 to the length of the chord line L 5462 and the ratio of the second chord height 5466 to the length of the chord line L 5462 are both preferably 0.016.
In an embodiment, referring to
It should be noted that one end of the front side projection 5461 bends towards the rotating direction of the fan 50, which causes partial bending of the pressure surface 543 and the suction surface 545 on the two sides of the fan blade 54. For example, parts, close to an attachment point between the front edge 546 and the top edge 544, of the pressure surface 543 and the suction surface 545 bend in the rotating direction of the fan 50.
It should be further noted that in the plane formed by the Y-axis and the Z-axis, the projection of the front edge 546 (i.e., the front side projection 5461) is located in front of the projection of the rear edge 548 in the rotating direction of the fan 50; and meanwhile, in the plane formed by the X-axis and the Y-axis, the projection of the rear edge 548 is closer to the air outlet 22 relative to the projection of the front edge 546. In this case, the fan blade 54 on the hub 52 roughly obliquely extends in the radial direction relative to the hub 52.
Further, referring to
It should be noted that the bending angle of one end of the front side projection 5461 may be 5°, 7°, 9°, 11°, 13°, 14°, 15°, and the like.
In some embodiments, referring to
It should be noted that the projection of the front edge 546 in the plane formed by the X-axis and the Y-axis may be a straight line or a curve. It should be noted that if the projection of the front edge 546 in the plane formed by the X-axis and the Y-axis is the straight line, it does not mean that the front edge 546 is designed into a straight line structure in the three-dimensional space, because the front edge 546 in the plane formed by the Y-axis and the Z-axis may also be designed into the curve. For example, by observing in the plane formed by the Y-axis and the Z-axis, one end of the front edge 546 bends towards the rotating direction of the fan 50.
When the projection of the front edge 546 in the plane formed by the X-axis and the Y-axis is the curve, the curve may be a curve of the first degree or a curve of higher degree. For example, the projection of the front edge 546 in the plane formed by the X-axis and the Y-axis is firstly convex towards one side of the air inlet 11 of the housing 10 from the end close to the root portion 542 to the end close to the top edge 544, and then is concave towards one side of the air outlet 22. Of course, the projection may continue to be sequentially convex and concave.
Specifically, referring to
In some embodiments, referring to
It should be noted that the tangent line at the end point of the front edge 546 close to the hub 52 may also be understood as a tangent line, at the intersection point of the front edge 546 and the root portion 542 of the fan blade 54, of the projection of the front edge 546 in the plane formed by the X-axis and Y-axis. In addition, the included angle θ may be but not limited to 3°, 6°, 9°, 12°, 15°, 18°, 21°, 24°, 25°, and the like.
Specifically, the included angle θ is preferably 6°, such that the airflow tends to be slow, thereby reducing formation of turbulence and effectively reducing the noise.
In some embodiments, referring to
It should be noted that the front edge 546 of the fan blade 54 includes a curved profile in a meridional plane established by axial and radial axes (i.e., the plane formed by the X-axis and the Y-axis), and the rear edge 548 includes a curved profile in the meridional plane established by the axial and radial axes. In other words, the fan blade 54 is in a twisted state in the three-dimensional space. For example, when the fan blade 54 is observed in the meridional plane defined by the axial and radial axes extending parallel to the fan axis 51, both the front edge 546 and the rear edge 548 of the fan blade 54 have the curved profiles.
It is to be understood that in some other embodiments, the projection of at least part of at least one of the front edge 546 and the rear edge 548 in the plane perpendicular to the fan axis 51 may also have a straight profile, and correspondingly, the projection of at least part of at least one of the front edge 546 and the rear edge 548 in the above meridional plane may also have a straight profile, which is not limited herein.
It should be particularly noted that at least part of at least one of the projections of the front edge 546 and the rear edge 548 in the plane perpendicular to the fan axis 51 has the curved profile, at least one of the front edge 546 and the rear edge 548 deviates, in terms of a rotation angle of the fan 50, from a line extending in the radial direction from a center point of the fan 50, such that the front edge 546 of the fan blade 54 is swept rearwards, and the rear edge 548 is swept frontwards. In the specific embodiment shown in
Further, referring to
It should be noted that the included angle δ may be but not limited to 8°, 10°, 12°, 14°, 16°, 18°, 20°, and the like.
Specifically, the included angle δ is preferably 14°, such that the airflow tends to be slow, which is more conductive to reducing the noise.
It should be further noted that an included angle between a tangent line, at one end point of the rear edge 548 close to the top edge 544, of the projection of the rear edge 548 in the plane formed by the X-axis and the Y-axis and the X-axis is 0° (not including 0°) to 45°.
In some embodiments, referring to
In some embodiments, referring to
In order to further arrange more fan blades 54 on the hub 52, the cross section of the root portion 542 of the fan blade 54 is different from the cross section of the top edge 544 of the fan blade 54 in shape, and the length of the root portion 542 of the fan blade 54 in the extending direction thereof is smaller than the length of the top edge 544 of the fan blade 54 in the extending direction thereof, in other words, the length of the side, connected with the hub 52, of the fan blade 54 in the extending direction thereof is smaller than the length of the side, away from the hub 52, of the fan blade 54 in the extending direction thereof. The smaller diameter of a joint between the hub 52 and the fan blade 54 leads to a small circumference. When the length of the root portion 542 of the fan blade 54 in the extending direction thereof is smaller than the length of the top edge 544 of the fan blade 54 in the extending direction thereof, more fan blades 54 may be arranged in the circumferential direction of the hub 52.
In addition, the installation included angle γ between the installation line 547 and the X-axis is gradually increased from the root portion 542 to the top edge 544, such that the pressure gradient of the front edge 546 and the rear edge 548 of the fan blade 54 may be in smooth transition and changing from the root portion 542 to the top edge 544, thereby reducing the tendency of separation of the airflow from the fan blade 54, reducing the turbulence in the airflow, and minimizing the noise.
It should be noted that a changing transition rate of the installation included angle γ between the installation line 547 and the X-axis from the root portion 542 to the top edge 544 may be kept consistent, or not consistent. For example, the changing transition rate from the installation included angle γ at the root portion 542 to the installation included angle γ at a radial midpoint of the fan blade 54 between the root portion 542 and the top edge 544 is lower than the changing transition rate from the installation included angle γ at the midpoint to the installation included angle γ at the top edge 544, and the like.
Further, referring to
In some embodiments, referring to
It should be noted that when the installation included angle γ at the root portion 542 is 5° to 30° and the included angle γ at the top edge 544 is 30° to 85°, the pressure gradient between the fan blades 54 more tends to be in smooth transition and changing, thereby effectively reducing the turbulence in the airflow, and minimizing the noise.
In some embodiments, referring to
Further, a radius length of the curved surface transition portion 541 ranges from 2 mm to 6 mm. Of course, in some other embodiments, the radius length of the curved surface transition portion 541 may also be limited within 0.5 mm to 5 mm, for example, the radius length of the curved surface transition portion 541 may be 0.5 mm, 2 mm, 3 mm, 4 mm, and 5 mm.
In some embodiments, a corner radius of a projection of the curved surface transition portion 541 in the plane formed by the X-axis and the Y-axis is 1 mm to 5 mm. For example, the corner radius may be but not limited to 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, and the like. Thus, the vortex formed by the blade tip of the fan blade 54 during rotation can be better reduced, so as to reduce the blade frequency high-pitched noise.
In some embodiments, referring to
In some embodiments, referring to
In some other specific embodiments, the width of the outer portion of the front edge 546 is gradually reduced in a forward stretching direction, and the width of the top edge 544 is gradually reduced in the stretching direction from the rear edge 548 to the front edge 546, such that a sharp end is formed at the junction of the front edge 546 and the top edge 544, which can similarly play the role of cutting the airflow.
In some embodiments, referring to
It should be noted that the fan 50 may be entirely located in the duct 30, or partially located in the duct 30. Of course, during structure design of the fan 50 and the duct 30, the fan 50 and the duct 30 may be spaced, for example, the duct 30 is located at a downstream end of the fan 50 in the airflow flowing direction.
Meanwhile, the duct 30 is arranged in the air channel portion 12 of the housing 10, and the duct 30 is configured for guiding the airflow to move and rectify the airflow generated by the fan 50. Thus, the duct 30 is located at the downstream region of the air channel portion 12. After the airflow at the upstream region of the air channel portion 12 enters the air channel portion 12 from the air inlet 11, the airflow moves towards the fan 50, and after passing through the fan 50, the airflow moves to the downstream region from the upstream region of the air channel portion 12 to be rectified by the duct 30 and is finally blown out from the blowing tube 20.
In some embodiments, referring to
According to the garden tool 100 with a blowing function, in the airflow flowing process, the speed of the airflow at the top 364 of the first stationary vane 36 is greater than the speed of the airflow at the bottom 362 of the first stationary vane 36 due to the action of air pressure. One end of the first front side edge 366 of the first stationary vane 36 at the bottom 362 is set to be located downstream of the other end of the first front side edge 366 at the top 364, which effectively increases the distance between the end of the first front side edge 366 of the first stationary vane 36 at the top 364 and the fan blade 54. Accordingly, on one hand, the flow path of the high-speed airflow is extended, and noise produced when the airflow impacts the first stationary vane 36 is reduced; and on the other hand, the speed difference of the airflow at the top 364 and the bottom 362 of the first stationary vane 36 is in smooth transition, thereby avoiding the generation of vortex, and further reducing the noise.
It should be noted that the outer guide cover 32 is roughly arranged in the direction of the fan axis 51, the inner guide cover 34 is located in a center of the outer guide cover 32, an airflow circulation space is formed between the outer guide cover 32 and the inner guide cover 34, and a cross section, perpendicular to the fan axis 51, of the circulation space is roughly in a ring shape. The first stationary vanes 36 are located in the ring-shaped circulation space and distributed around the inner guide cover 34 at equal intervals, and a gap between every two spaced first stationary vanes 36 allows the airflow to circulate.
As an implementation, the number of the first stationary vanes 36 is 3 to 11, which can play a flow guiding role without hindering airflow passing or increasing noise caused by too many first stationary vanes 36.
In addition, the inner guide cover 34 also roughly extends in the direction of the fan axis 51; the inner guide cover 34 is hollow inside; and a sectional area of the inner guide cover 34 in a direction perpendicular to the fan axis 51 is less than or equal to a maximum sectional area of the hub 52 of the fan 50 in the direction perpendicular to the fan axis 51.
As an optional implementation, the whole motor is arranged in the inner guide cover 34, or at least part of the motor is arranged in the inner guide cover 34. Preferably, the inner guide cover 34 is cylindrical, the first stationary vanes 36 between an outer wall of the inner guide cover 34 and an inner wall of the outer guide cover 32 are evenly arranged in the direction of the fan axis 51, such that the airflow can be guided to move in a direction parallel to the fan axis 51, thereby avoiding the noise produced by the vortex.
Further, the inner guide cover 34 includes an accommodating portion and a guide portion connected with the accommodating portion. The accommodating portion is arranged close to the fan 50 and is configured for accommodating the motor, and the guide portion is arranged close to the blowing tube 20 and is integrally formed with the accommodating portion. An installation hole 346 is formed in a rear end, close to the fan 50, of the accommodating portion. The motor is fixed into the accommodating portion through the installation hole 346. One end (front end), close to the blowing tube 20, of the guide portion is provided with an opening configured for guiding out airflow entering the inner guide cover 34. An air guide hole 340 is further formed in the rear end of the accommodating portion. A cooling channel for cooling the motor is formed between the air guide hole 340 and the opening, and the airflow inflows from the air guide hole 340 and outflows from the opening, so as to cool the motor.
It should be noted that there is only one air guide hole 340, and of course, there may also be a plurality of air guide holes 340. As shown in
In some embodiments, referring to
In some embodiments, referring to
Further, referring to
In some embodiments, referring to
It should be noted that a part of the stationary vane section 31 crossing the X′-axis should be understood as: at least part of the stationary vane section 31 close to the air outlet 22 of the blowing tube 20 is located on one side of the X′-axis or is directly located on the line of the X′-axis, and a part of the stationary vane section 31 close to the fan 50 bends and extends, crosses the X′-axis, and is located on the other side of the X′-axis.
In some embodiments, referring to
Through researches and development, when the blade inlet installation angle is too large, the inlet impact loss is increased, the blade inlet flow condition is not good, and vortex noise is increased. However, when the blade inlet angle is reduced, the sound pressure level of inlet noise is gradually reduced, but as further decrease in the inlet installation angle, the inlet separation loss of the inlet angle is increased, and the vortex noise is increased as well. Thus, the noise of the garden tool 100 with a blowing function can be reduced by selecting the proper inlet angle. The inventors found through further researches that by setting the inlet angle Le of the first stationary vane 36 to be at 35° to 65°, the efficient flow condition of the airflow can be ensured, and the vortex noise is reduced, thereby reducing the overall noise influence and improving user experience.
In some embodiments, referring to
It should be noted that the maximum height in the direction of the Z′-axis should be understood as: a curved part has an upper end point farthest from the X′-axis after the stationary vane section 31 crosses the X′-axis and bends; and a part of the stationary vane section 31 does not cross the X′-axis or located on the line of the X′-axis has a lower end point farthest from the upper end point. In this case, the maximum height in the direction of the Z′-axis may be a distance between the upper end point and the lower end point in the direction of the Z′-axis.
Further, referring to
In some embodiments, referring to
In some embodiments, referring to
Further, referring to
It should be noted that the included angles may be but not limited to 60°, 70°, 80°, and the like. In some specific embodiments, the included angle ε is preferably 84°.
It should be further noted that the projection of the first front side edge 366 in the plane formed by the X′-axis and the Y′-axis may be a straight profile or a curve profile. When the projection is the curve profile, it may be a curve of the first degree, a quadratic curve, and the like. For example, a part, close to the inner guide cover 34, of the projection of the first front side edge 366 in the plane formed by the X′-axis and the Y′-axis is convex towards the side of the fan 50; and a part close to the outer guide cover 32 is concave towards the side of the air outlet 22.
In some embodiments, referring to
Further, referring to
Further, an included angle c between a tangent line at a position, close to the top 364, of the projection of the first rear side edge 368 in the plane formed by the X′-axis and the Y′-axis, and the X′-axis is smaller than the included angle b. In other words, the curvature of the first rear side edge 368 close to the top 364 is greater than the curvature of the first rear side edge 368 close to the bottom 362, such that a tip part of the first rear side edge 368 can be extended towards the side of the air outlet 22, thereby ensuring that the speed difference of the airflow at the top 364 and the bottom 362 of the first stationary vane 36 is further reduced, ensuring more uniform airflow flowing, and facilitating noise reduction.
It should be noted that the included angle c may be any value between 30° and 90°, for example, the included angle c is 30°, 35°, 40°, 45°, 50°, 60°, 70°, 80°, and the like.
In some embodiments, referring to
Further, the first angle is not equal to the second angle, such that the tendency of separation of the airflow from the first stationary vane 36 can be reduced, turbulence in the airflow is reduced, and the noise is minimized. It is particularly emphasized that the main function of the first stationary vane 36 is to rectify the airflow, so as to guide the airflow to flow roughly in the direction of the fan axis 51, and thus, the first stationary vane 36 roughly extends in the direction of the fan axis 51. The first angle and the second angle are kept within a range of 0° to 30°, such that the airflow can be well guided, and meanwhile the noise reduction effect is achieved.
In some embodiments, a length of the first stationary vane 36 is L1, a mid-arc line chord length of the fan blade 54 of the fan 50 is L2, and 3≤L1:L2≤9. It should be noted that, referring to
It is to be understood that aerodynamic performance parameters of the fan blade 54, such as a geometric air inlet angle, a geometric air outlet angle, a maximum blade thickness, and a maximum deflection are all based on a mid-arc line of the blade, and thus, an error of the mid-arc line directly affects the accuracy of the calculation of aerodynamic performance of the fan 50. The aerodynamic performance of the fan 50 is directly related to the noise produced in the airflow flowing process. The inventors found through researches that rectification and noise reduction performance of the first stationary vane 36 are correlated to the mid-arc line of the fan 50, and found through further researches that one end of the first front side edge 366 at the bottom 362 is located downstream of the other end of the first front side edge 366 at the top 364, and one end of the first rear side edge 368 at the bottom 362 is located upstream of the other end of the first rear side edge 368 at the top 364, such that the length of the first stationary vane 36 varies between the bottom 362 and the top 364. By comprehensively considering the airflow speed and the air pressure, the length of the first stationary vane 36 is set to be 3 to 9 times the mid-arc line chord length of the fan blade 54. On the premise of ensuring good rectification performance, the generation of vortex in the airflow is significantly reduced, which correspondingly leads to a significant decrease in the decibel level of the noise, and the user experience is improved.
In an embodiment, referring to
According to the garden tool 100 with a blowing function, the rotation angle of the airflow produced due to rotation of the fan 50 is reduced under guidance of the first stationary vanes 36. By arranging the second stationary vanes 39, the airflow is further guided to flow in the direction of the fan axis 51, the rotation vortex in the airflow is reduced, and the noise is reduced, thereby further reducing the noise effect, and particularly reducing the vortex frequency in the airflow flowing process, so as to reduce the frequency-doubled high-pitched noise.
It should be noted that the second stationary vanes 39 are located downstream of the first stationary vanes 36, and extend lengthwise in an axial direction of an outer wall of the guide cone 38.
Specifically, referring to
In some embodiments, referring to
It is to be understood that in some other embodiments, the second stationary vanes 39 may also be detachably connected with the guide cone 38, which is not limited herein.
Further, referring to
Further, referring to
In some embodiments, referring to
In some embodiments, referring to
In some embodiments, referring to
According to the garden tool 100 with a blowing function, the third stationary vanes 40 are arranged downstream of the first stationary vanes 36, and after airflow rectified by the first stationary vanes 36 is guided by the third stationary vanes 40, the airflow basically becomes parallel airflow flowing in the direction of the fan axis 51, thereby avoiding the high-pitched noise generated by the rotational impact of the airflow in the air channel portion 12 and the blowing tube 20, and further improving the noise reduction effect.
Although not expected to be limited by the theory, after rectification through the first stationary vanes 36 and the second stationary vanes 39, the decibel level of noise of the garden tool 100 with a blowing function is significantly reduced. In order to achieve the purpose of lower noise, referring to
In some embodiments, referring to
In some embodiments, referring to
In some embodiments, referring to
In some embodiments, referring to
The inventors of this application verify through tests that by adopting the plurality of stationary vanes for flow guiding, the decibel level of the noise can be reduced by 1 to 3 decibels, and the high-pitched noise can be reduced by 2 to 5 decibels, and the air channel efficiency of the air channel portion 12 is improved by 2%.
In some embodiments, referring to
According to the garden tool 100 with a blowing function, the three-dimensional air inlet array grid is designed to have the outward convex arc envelope surface. Outer envelope surfaces and/or inner envelope surfaces of the plurality of grid units 62 are in smooth transition, which can reduce flow losses of the airflow to the maximum degree, meanwhile, intake airflow may tend to be uniform through the plurality of grid units 62 arranged towards the periphery from a center of the air intake shield 60, such that roughly parallel intake airflow is generated, and rotational flow generated at frameworks of the different grid units 62 may offset with each other. Accordingly, on one hand, fluctuation of the airflow in space can be weakened without increasing the number of the grid units 62, and the airflow entering the air intake shield 60 tends to be parallel, thereby reducing the generation of vortex and then reducing the noise. On the other hand, air flowing and efficiency can be improved, and the air inlet efficiency is improved. In addition, as the ejection portions 68 of the flow-breaking ribs 66 protrude relative to the webs 61 in the direction away from the air inlet 11, in other words, at least part of the ejection portions 68 protrude from the webs 61, when the airflow enters the grid units 62, the airflow is stopped by two adjacent ejection portions 68 and then divided towards the periphery; and after flow division, the airflow is then stopped by two adjacent webs 61, such that the airflow can be prevented from being stopped by the two adjacent webs 61 and the two adjacent ejection portions 68 at the same time, thereby effectively increasing the intake air flow and reducing air resistance.
It should be noted that the ejection portion 68 may be of a plane structure. For example, the ejection portion 68 may be a complete plane, or is formed by splicing a plurality of planes with included angles therebetween, or may be an arch-shaped or curved cambered surface, and the like. Of course, the ejection portion 68 may also be of a point or linear structure. For example, the ejection portion 68 is an end point of a circular cone; or may be an included angle line formed by intersecting two side surfaces of the ejection portion 68; or the like.
Referring to
Further, referring to
In addition, in some specific embodiments, the first air guide portion 681 and the second air guide portion 682, wherein the first air guide portion 681 and the second air guide portion 682 extend towards the adjacent spaced webs 61 are respectively of structures located on two opposite sides of the ejection portion 68 in the second direction 661 and obliquely extending towards the webs 61, such that the airflow can be guided according to a preset path, and rotational flow is avoided, thereby reducing the noise.
It should be noted that the height distance D6 may be 2 mm, 3 mm, 5 mm, 8 mm, 11 mm, 14 mm, 17 mm, 20 mm, and the like. In some specific embodiments, the height distance D6 is preferably 3 mm to 8 mm.
In some embodiments, referring to
It should be noted that the auxiliary air inlet regions should be understood as a plurality of spaces surrounding outside the main air inlet region at intervals, which are formed between the three-dimensional air inlet array grid and an inner wall of the frame 64 when the three-dimensional air inlet array grid is connected inside the frame 64, in other words, the spaces are defined by the non-closed “grid units 62” and the inner wall of the frame 64. The main air inlet region is a space formed by combining the plurality of completely closed “grid units 62”.
In some embodiments, the plurality of grid units 62 are arranged into a plurality of rows at intervals in the second direction 661. The grid units 62 in each row are arranged in the first direction 612. The two most adjacent grid units in adjacent rows are staggered in the first direction 612. The first direction 612 intersects with the second direction 661. Specifically, the first direction 612 is a transverse direction shown in
In some embodiments, referring to
In some embodiments, the ejection portion 68 has a top surface 652 on the windward side 65. The first air guide portion 681 and the second air guide portion 682 are respectively a first air guide surface 654 and a second air guide surface 656 on the windward side 65. As an implementation, the webs 61 are basically parallel to the axis of the air inlet 11, which is conducive to guiding the airflow. A thickness of the web 61 is 0.25 mm to 2 mm.
Referring to
Further, referring to
In some embodiments, referring to
The inventors of this application verify through tests that by adopting the above air intake shield 60, the decibel level of the noise can be reduced by 1 to 2 decibels, the high-pitched noise can be reduced by 1 decibel, and the air channel efficiency of the air channel portion 12 is improved by 1% to 2%.
In some embodiments, referring to
Of course, in some other embodiments, the included angle f between the second air guide surfaces 656 of the flow-breaking ribs 66 in the same column in the second direction 661 and the shield axis 63 may be kept unchanged from the edge of the three-dimensional air inlet array grid to the shield axis 63.
In some embodiments, referring to
An included angle g between the fourth air guide surface 611 of the web 61 facing away from the shield axis 63 and the shield axis 63 is gradually reduced from the edge of the three-dimensional air inlet array grid to the shield axis 63 in the second direction 661. Of course, in some other embodiments, the included angle g may also be kept unchanged from the edge of the three-dimensional air inlet array grid to the shield axis 63 in the second direction 661.
In some embodiments, referring to
It should be noted that the distance between the adjacent webs 61 may be 5 mm, 7 mm, 9 mm, 11 mm, 13 mm, 15 mm, and the like.
In some embodiments, referring to
Optionally, one side surface of the web 61 facing the intake air may be a curved surface, or may also be formed by splicing a plurality of planes with included angles therebetween.
In some embodiments, referring to
Further, the outer envelope surface of the three-dimensional air inlet array grid protrudes out of one end surface of the frame 64 facing away from the air inlet 11. Thus, the outer envelope surface protrudes out of the frame 64, which is conducive to increasing the structure strength, and limiting the noise radiation.
In addition, in some embodiments, the air intake shield 60 has a shield axis 63. One end surface of the frame 64 facing away from the air inlet 11 inclines relative to the shield axis 63.
In some embodiments, referring to
According to the garden tool 100 with a blowing function, in order to further reduce the noise, the inventors found through researches that air is sucked in through the air intake shield 60 and the air inlet 11 during rotation of the fan 50, airflow passes through the air intake shield 60 and generates roughly parallel intake airflow, but there is still non-parallel airflow, which causes vortex. In order to solve the problems, referring to
In some specific implementations, a distance between the guide vane 90 and the air inlet 11 is 10 mm to 50 mm; the number of the guide vanes 90 is 5 to 20; a distance between every two adjacent guide vanes 90 is 12 mm to 18 mm; and a chord length of each guide vane 90 is 10 mm to 50 mm. As a preferred implementation, the distance between the adjacent guide vanes 90 is 15 mm, which can achieve a good noise reduction effect.
Further, referring to
Further, the fan axis 51 is located on the symmetric reference plane. Projections of parts, located on the bending section 14, of the upper edge of the first half housing and the upper edge of the second half housing towards the symmetric reference plane are overlapped and have a third curved profile, and projections of parts, located on the bending section 14, of the lower edge of the first half housing and the lower edge of the second half housing towards the symmetric reference plane are overlapped and have a fourth curved profile. As shown in
The guide vanes 90 are connected to the inner wall of the housing 10 located on the bending section 14, and located on the airflow flowing path. Specifically, the guide vane 90 includes a first sub-guide vane 9290 and a second sub-guide vane 9490 which are symmetrically arranged relative to the symmetric reference plane. When the first half housing and the second half housing are adaptively connected, the first sub-guide vane 9290 and the second sub-guide vane 9490 are coupled to form the complete guide vane 90. In a specific embodiment, the first sub-guide vane 9290 and the second sub-guide vane 9490 are both provided with an upper flow guide surface and a lower flow guide surface making contact with airflow, and after the first sub-guide vane 9290 and the second sub-guide vane 9490 are coupled, the corresponding flow guide surfaces of the first sub-guide vane 9290 and the second sub-guide vane 9490 form a smooth curved surface. Of course, in order to make airflow flowing through the guide vanes 90 and the inner wall of the bending section 14 more smooth so as to reduce the noise, in some other embodiments, projections of the guide vanes 90 towards the symmetric reference plane have a fifth curved profile, and the fifth curved profile is of an arc shape. Mid-arc lines equally dividing the third curved profile and the fourth curved profile are perpendicular to and equally divide the fifth curved profile.
The inventors of this application verify through tests that by arranging the guide vanes 90 at the upstream region of the fan 50 close to the air inlet 11, the decibel level of the noise can be reduced by 2 to 3 decibels, the high-pitched noise can be reduced by 2 to 4 decibels, and the air channel efficiency of the air channel portion 12 is reduced by 1% or below.
In one of embodiments, the garden tool 100 with a blowing function further includes a power supply. The power supply is configured for supplying electric power to the motor, which may be a direct-current power supply, or specifically may be a rechargeable battery pack, and the battery pack may be detachably installed on the housing 10. Specifically, the housing 10 is provided with one or two or more battery pack installation portions for combining the battery pack. The battery pack installation portion may be arranged close to an operating handle, and the number of the battery packs is matched with the number of the battery pack installation portions. It is to be understood that the battery pack installation portion is required to be arranged close to the operating handle to allow a weight unit to be as close to a gripping point for operation as possible, thereby reducing the fatigue of the user during work.
The battery pack in one of embodiments can at least supply power to two different types of direct-current tools, for example, it may be suitable for the garden tool 100 with a blowing function, a grass trimmer, a mower, a chain saw, a pruner, an angle grinder, an electric hammer, an electric drill, and other garden tools 100. Accordingly, the user can only purchase a bare garden tool 100 with a blowing function, and supply power to the garden tool 100 with a blowing function by utilizing a battery pack of other existing garden tools 100 to realize energy sharing among multiple tools, which on one hand, benefits the universality of a battery pack platform, and on the other hand, reduces the purchase cost for the user. In a specific embodiment, the battery pack may be fixed to the battery pack installation portion in a snap-fit manner or a plug-in manner. For example, in some embodiments, the battery pack includes slide rail portions (unnumbered) arranged on two sides of the battery pack, a snap-fit portion arranged on an upper side of the battery pack, and a plurality of electrode connecting sheets (not shown in the figure). The slide rail portions may be adaptively connected with the battery pack installation portion to limit the battery pack in the radial direction, and the snap-fit portion is in snap-fit connection with the housing 10 to limit the battery pack in the axial direction, such that the battery pack is stably connected to the battery pack installation portion.
Various technical features of the foregoing embodiments may be combined at will. For brevity of the description, it is unnecessary to describe all possible combinations of the various technical features of the foregoing embodiments, however, the combinations of these technical features should fall within the scope recorded by this specification as long as there is no contradiction.
The foregoing embodiments only show several implementations of the present disclosure, which are specifically described in detail but cannot be understood as limitations on the patent scope of the present disclosure. It should be noted that a plurality of transformations and improvements can also be made by those of ordinary skill in the art without departing from the conception of the present disclosure, which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be determined by the claims attached hereto.
In the description of the present disclosure, it is to be understood that orientation or position relationships indicated by terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “clockwise”, “anticlockwise”, “axial direction”, “radial direction”, “circumferential direction”, and the like are orientation or position relationships shown based on the drawings, are adopted not to indicate or imply that indicated devices or elements must be in specific orientations or structured and operated in specific orientations but only to conveniently describe the present disclosure and simplify the description, and thus should not be understood as limitations on the present disclosure.
In addition, terms “first” and “second” are used for descriptive purposes only, and cannot be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, features defined with “first” and “second” may explicitly or implicitly include at least one of the feature. In the description of the disclosure, “a plurality of” means at least two, such as two and three, unless otherwise expressly limited.
In the present disclosure, unless otherwise expressly specified and limited, terms “mounted”, “linked”, “connected”, “fixed”, and the like are to be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integrated connection; a mechanical connection, or an electrical connection; a direct connection, an indirect connection through an intermediate medium, an internal communication of two elements, or interaction between two elements, unless otherwise expressly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific situations.
In the present disclosure, unless otherwise expressly specified and limited, a first feature being “above” or “below” a second feature may be a direct contact between the first feature and the second feature, or an indirect contact between the first feature and the second feature through an intermediate medium. In addition, the first feature is “over”, “above”, and “on” the second feature may be that the first feature is directly above or diagonally above the second feature, or merely means that the first feature is higher than the second feature in the horizontal height. The first feature is “under”, “below”, and “underneath” the second feature may be that the first feature is directly below or diagonally below the second feature, or merely means that the first feature is lower than the second feature in the horizontal height.
It should be noted that when an element is “fixed to” or “arranged on” another element, it means that the element may be directly arranged on the another element or there may be an intermediate element. When an element is considered to be “connected to” another element, it means that the element may be directly connected to the another element or there may be an intermediate element at the same time. Terms “perpendicular”, “horizontal”, “upper”, “lower”, “left”, “right”, and similar expressions used in the specification are for illustrative purposes only and do not imply an exclusive implementation.
Number | Date | Country | Kind |
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202110268034.9 | Mar 2021 | CN | national |
This application is a Continuation bypass of application of PCT Application No. PCT/CN/080647, filed on Mar. 14, 2022, which claims priority to Chinese Patent Application No. 202110268034.9, filed on Mar. 12, 2021, all of which are hereby incorporated by reference in their entirety for all purposes as if fully set forth herein.
Number | Date | Country | |
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Parent | PCT/CN2022/080647 | Mar 2022 | US |
Child | 18244743 | US |