Patent Publication Number: US-2020296904-A1

Title: Blowing suction device

Description:
This application is a Continuation Application of International Application No. PCT/CN2018/120684, filed on Dec. 12, 2018, which claims benefit of and priority to Chinese Patent Application No. 201711316309.1, filed on Dec. 12, 2017, all of which are hereby incorporated by reference in their entirety for all purposes as if fully set forth herein. 
     BACKGROUND 
     Technical Field 
     The present invention relates to, and in particular, a single-tube blowing suction device. 
     Related Art 
     In some existing blowing suction devices, a blowing tube and a suction tube are detached and assembled alternately to implement switching between blowing and suction. In such a solution, a user needs to detach a blowing tube and a suction tube during use, resulting in complex operations, undesirable human-machine interaction, and inconvenient use. 
     SUMMARY 
     In view of the foregoing status in the prior art, one objective of the present invention is to provide a single-tube blowing suction device, so that it is not necessary to detach a blowing tube and a suction tube in switching between blowing and suction, and an operation of switching between blowing and suction is simple. 
     To achieve the foregoing objective, the technical solution adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a grip portion to be held by an operator; 
     an airflow generation apparatus, connected to the body, and including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication with the outside; and 
     a blowing-suction tube, having an opening in communication with the outside for air flowing into or flowing out, wherein 
     the volute is pivotally disposed relative to the grip portion and is rotatable between at least a blowing position in the blowing mode and a suction position in the suction mode, when the volute rotates to the blowing position, an airflow flows into an inner cavity of the volute from the air inlet portion and then flows into the blowing-suction tube from the air outlet portion of the volute, and when the volute rotates to the suction position, an airflow enters into the volute from the opening and then flows out from the air outlet portion. 
     In one of the embodiments, the grip portion extends longitudinally along a first axis, the blowing-suction tube extends longitudinally along a second axis, and when the volute rotates between the blowing mode and the suction mode, an angle formed between the first axis and the second axis remains unchanged. 
     In one of the embodiments, the blowing-suction tube is a single-cavity air tube, and when the blowing suction device is in the blowing mode or the suction mode, an extending direction of the blowing-suction tube remains unchanged. 
     In one of the embodiments, the air inlet portion includes an air inlet opening capable of being in communication with the outside in the blowing mode, and the air outlet portion includes an air outlet opening allowing sucked foreign objects to flow outside; and 
     the fan includes an air inlet side perpendicular to the output shaft of the motor and an air outlet side parallel to the output shaft of the motor, in the blowing mode, the air inlet opening is located right above the air inlet side, and the air outlet opening is located in front of the air outlet side, and in the suction mode, the air inlet opening is located in front of the air inlet side, and the air outlet opening is located right below the air outlet side. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, and when the blowing suction device switches between the blowing mode and the suction mode, the independent integral structure is integrally rotatable relative to the grip portion. 
     In one of the embodiments, the blowing suction device further includes a blowing-suction switching mechanism, and the blowing-suction switching mechanism operably drives the airflow generation apparatus to pivot around a rotational axis A relative to the grip portion. 
     In one of the embodiments, the blowing-suction switching mechanism includes a toggle, and the blowing-suction tube includes a first end near the airflow generation apparatus, 
     when the blowing suction device switches from the suction mode to the blowing mode, the toggle controls the first end of the blowing-suction tube to be disengaged from the air inlet portion, and when the blowing suction device switches from the blowing mode to the suction mode, the toggle controls the first end of the blowing-suction tube to be disengaged from the air outlet portion. 
     In one of the embodiments, the blowing-suction switching mechanism further includes an operation component pivotally mounted on the body, and the operation component operably drives the airflow generation apparatus to rotate to the blowing position or the suction position. 
     In one of the embodiments, the body includes a main unit housing connected to the grip portion, the main unit housing is provided with a body air inlet portion and a blowing-suction tube connecting portion for mounting the blowing-suction tube, and the body air inlet portion is located below the grip portion. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a grip portion and a main unit housing connected to the grip portion, the main unit housing being provided with an opening in communication with the outside; 
     an airflow generation apparatus, connected to the main unit housing, and including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in fluid communication with the opening; and 
     a blowing-suction tube, having a tube opening in communication with the outside for air flowing into or flowing out, wherein 
     the volute is pivotally disposed relative to the main unit housing and is rotatable between at least a blowing position in the blowing mode and a suction position in the suction mode, when the volute rotates to the blowing position, an airflow flows into an inner cavity of the volute from the air inlet portion and flows into the blowing-suction tube from the air outlet portion of the volute, and when the volute rotates to the suction position, an airflow enters the inner cavity of the volute from the tube opening and flows out from the air outlet portion. 
     In one of the embodiments, the grip portion and the main unit housing are integrally disposed. 
     In one of the embodiments, the main unit housing is provided with a front-end opening and a rear-end opening penetrating in an extending direction of the blowing-suction tube, and the airflow generation apparatus at least partially extends backward and is exposed from an outer side of the rear-end opening. 
     In one of the embodiments, the blowing suction device includes a collection apparatus detachably connected to the air outlet portion, and the collection apparatus is at least partially located right below the air outlet portion. 
     To achieve the foregoing objective, the technical solution adopted in the embodiments of the present disclosure is a single-tube blowing suction device, including: a body; an airflow generation apparatus for generating an airflow, connected to the body; a collection apparatus used for collecting debris; and a blowing-suction tube, connected to the body, where the airflow generation apparatus has an air inlet portion and an air outlet portion, the airflow generation apparatus is rotatably mounted on the body, the airflow generation apparatus is enabled to rotate relative to the body to enable the single-tube blowing suction device to switch between a suction mode and a blowing mode, in the suction mode, the air inlet portion of the airflow generation apparatus is in fluid communication with a connection port of the collection apparatus, and in the blowing mode, the air outlet portion of the airflow generation apparatus is in fluid communication with a first end of the blowing-suction tube. 
     In one of the embodiments, a cross-sectional area of an air inlet channel of the air inlet portion in a direction perpendicular to an air inlet direction of the air inlet channel is greater than a cross-sectional area of an air outlet channel of the air outlet portion in a direction perpendicular to an air outlet direction thereof. 
     In one of the embodiments, the blowing-suction tube is a straight tube, and a second end of the blowing-suction tube is formed with a tilted opening tilting in an extending direction of the blowing-suction tube. 
     In one of the embodiments, the body further includes a body air inlet portion, and in the blowing mode, the air inlet portion of the airflow generation apparatus is in fluid communication with the body air inlet portion. 
     In one of the embodiments, in the suction mode, the air inlet portion of the airflow generation apparatus is in direct communication with the first end of the blowing-suction tube, the air outlet portion of the airflow generation apparatus is in direct communication with the connection port of the collection apparatus, and in the blowing mode, the air outlet portion of the airflow generation apparatus is in direct communication with the first end of the blowing-suction tube, and the air inlet portion of the airflow generation apparatus is in direct communication with the body air inlet portion. 
     In one of the embodiments, the airflow generation apparatus includes: a motor; a fan driven by the motor; and a volute surrounding the fan, the volute including the air inlet portion and the air outlet portion of the airflow generation apparatus. 
     In one of the embodiments, the single-tube blowing suction device further includes a rotation driving portion used for driving the volute to rotate, and the rotation driving portion is connected to the volute and is exposed from the body. 
     In one of the embodiments, in the suction mode, and the air inlet portion is sleeved over the first end of the blowing-suction tube from the periphery of the first end of the blowing-suction tube. 
     In one of the embodiments, in the blowing mode, the air outlet portion is clamped at the blowing-suction tube through a clamping groove formed in the air outlet portion. 
     In one of the embodiments, the air outlet portion includes an inner tube, an outer fastening portion, and a clamping groove defined between the inner tube and the outer fastening portion, and in the blowing mode, a circumferential wall of the first end of the blowing-suction tube is clamped in the clamping groove. 
     In one of the embodiments, the single-tube blowing suction device further includes a toggle, the toggle is pivotally mounted on the body at a middle position of the toggle, a first end of the toggle is pivotally connected to the blowing-suction tube, and a second end of the toggle is exposed from the body, and 
     the second end of the toggle is pushed to enable the toggle to rotate relative to the body, and the first end of the toggle drives the blowing-suction tube to move toward or away from the airflow generation apparatus. 
     In one of the embodiments, the single-tube blowing suction device further includes a linkage apparatus for linking the rotation of the airflow generation apparatus and an axial movement of the blowing-suction tube toward or away from the airflow generation apparatus, and the linkage apparatus includes a crank connecting rod mechanism and a Geneva mechanism. 
     In one of the embodiments, the crank connecting rod mechanism converts a continuous rotation into the axial movement of the blowing-suction tube, and the Geneva mechanism converts the continuous rotation into intermittent rotation of the airflow generation of the airflow generation apparatus relative to the body. 
     In one of the embodiments, the linkage apparatus includes a connecting rod, a rotary disk, a convex rod, and a linkage member, a first end of the connecting rod is connected to the blowing-suction tube, a second end of the connecting rod is connected to an eccentric position of the rotary disk, the rotary disk is rotatably mounted on the body and includes an arc-shaped surface, the convex rod is fastened to the rotary disk, the linkage member is fastened to the airflow generation apparatus, and the linkage member includes a first sliding surface and a second sliding surface matching the arc-shaped surface and a slot joined to the convex rod. 
     In one of the embodiments, the single-tube blowing suction device further includes a switching assisting apparatus, the switching assisting apparatus is disposed around a rotational axis of the airflow generation apparatus, the switching assisting apparatus includes an energy accumulation portion, when the single-tube blowing suction device switches between the suction mode and the blowing mode, the energy accumulation portion accumulates energy resisting the weight application of the airflow generation apparatus and surrounding a torque of the rotational axis, and the accumulated energy can help the airflow generation apparatus to rotate along the weight application of the airflow generation apparatus and in a direction opposite a rotational direction of the rotational axis. 
     In one of the embodiments, the energy accumulation portion is a spring. 
     In one of the embodiments, the spring is a torsion spring. 
     In one of the embodiments, the torsion spring is disposed around the rotational axis, the switching assisting apparatus further includes a torsion spring limit portion disposed on the body and an abutting portion disposed at the airflow generation apparatus, when the single-tube blowing suction device switches from the suction mode to the blowing mode, the abutting portion abuts an arm of the torsion spring to accumulate energy in the torsion spring, and when the single-tube blowing suction device switches from the blowing mode to the suction mode, the energy accumulated in the torsion spring assists the airflow generation apparatus in rotation. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion to be held by an operator; 
     an airflow generation apparatus, connected to the body, and including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication with the outside; and 
     a blowing-suction tube, having a tube opening that is in communication with the outside and is used for admitting or discharging air, the blowing-suction tube being provided at a first end near the airflow generation apparatus; and 
     a collection apparatus, used for collecting a foreign object blown out from the air outlet portion, 
     the air inlet portion including an air inlet opening for an external airflow to enter an inner cavity of the volute, the air outlet portion including an air outlet opening capable of being connected to the collection apparatus, where 
     the volute is pivotally disposed relative to the holding portion and is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode, when the volute rotates to the blowing position, the air outlet opening is opposite the first end of the blowing-suction tube, and when the volute rotates to the suction position, the air inlet opening is joined to and in communication with the first end of the blowing-suction tube. 
     In one of the embodiments, the volute rotates counterclockwise or clockwise around a rotational axis A relative to the holding portion by 70 degrees to 110 degrees, to enable the blowing suction device to be in the blowing mode or the suction mode. 
     In one of the embodiments, when the blowing suction device switches from the suction mode to the blowing mode, the volute rotates counterclockwise around the rotational axis A by 90 degrees, and when the blowing suction device switches from the blowing mode to the suction mode, the volute rotates clockwise around the rotational axis A by 90 degrees. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, the blowing suction device further includes a blowing-suction switching mechanism, and the blowing-suction switching mechanism operably drives the airflow generation apparatus to rotate around the rotational axis A between the blowing position in the blowing mode and the suction position in the suction mode. 
     In one of the embodiments, the blowing-suction tube includes a first sub-blowing-suction tube formed with the tube opening and a second sub-blowing-suction tube disposed between the tube opening and the airflow generation apparatus, the second sub-blowing-suction tube operably displaces in an axial direction, and the second sub-blowing-suction tube has a first position near the airflow generation apparatus and a second position away from the airflow generation apparatus, 
     when the second sub-blowing-suction tube is at the first position and the blowing suction device is in the blowing mode, the second sub-blowing-suction tube is opposite the air outlet portion, and when the second sub-blowing-suction tube is at the first position and the blowing suction device is in the suction mode, the second sub-blowing-suction tube is joined to the air inlet portion. 
     In one of the embodiments, both when the blowing suction device is in the blowing mode and when the blowing suction device is in the suction mode, an axial distance between the foremost end of the tube opening and the rotational axis A remains unchanged. 
     In one of the embodiments, the blowing-suction switching mechanism includes a toggle controlling the second sub-blowing-suction tube to move toward the first position or controlling the second sub-blowing-suction tube to move toward the second position, and the toggle is pivotally connected to the body. 
     In one of the embodiments, the blowing-suction switching mechanism further includes an operation component pivotally mounted on the body, and when the second sub-blowing-suction tube is at the second position, the operation component operably drives the airflow generation apparatus to rotate to the blowing position or the suction position. 
     In one of the embodiments, the blowing suction device further includes a switching assisting apparatus connected between the body and the airflow generation apparatus, and the switching assisting apparatus includes a first retaining portion connected to the body, a second retaining portion connected to the airflow generation apparatus, and an elastic portion connected between the first retaining portion and the second retaining portion, 
     when the blowing suction device is in the blowing mode, the elastic portion is in a stretched state, and when the blowing suction device switches from the blowing mode to the suction mode, the elastic portion uses a restoring force thereof and coordinates with the blowing-suction switching mechanism to drive the airflow generation apparatus to rotate. 
     In one of the embodiments, the switching assisting apparatus is an extension spring. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, and when the blowing suction device switches between the blowing position and the suction position, the motor does not rotate relative to the fan, and the motor is in a rotatable state relative to the body. 
     In one of the embodiments, the body includes a main unit housing connected to the holding portion, the main unit housing is provided with a hollowed-out opening in communication with the outside, the air inlet portion of the airflow generation apparatus is in fluid communication with the opening, the main unit housing is provided with a front-end opening and a rear-end opening penetrating in an extending direction of the blowing-suction tube, and the airflow generation apparatus at least partially extends backward and is exposed from an outer side of the rear-end opening. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion to be held by an operator and a main unit housing connected to the holding portion, the main unit housing being provided with an opening in communication with the outside; 
     an airflow generation apparatus, connected to the main unit housing, and including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication with the outside; 
     a blowing-suction tube, having a tube opening in communication with the outside to admit or discharge air, the blowing-suction tube being provided at a first end near the airflow generation apparatus; and 
     a collection apparatus, used for collecting a foreign object blown out from the air outlet portion, 
     the air inlet portion including an air inlet opening in fluid communication with the opening in the blowing mode, and the air outlet portion including an air outlet opening capable of being connected to the collection apparatus in the suction mode, where 
     the volute is pivotally disposed relative to the main unit housing and is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode, when the volute rotates to the blowing position, the air outlet opening is opposite the first end of the blowing-suction tube, and when the volute rotates to the suction position, the air inlet opening is joined to and in communication with the first end of the blowing-suction tube. 
     In one of the embodiments, the holding portion and the main unit housing are integrally disposed. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     an airflow generation apparatus, including a motor, a fan driven by the motor to generate an airflow, and a volute surrounding the fan, the motor including a motor body and a motor output shaft extending from the motor body, the volute including an air inlet portion and an air outlet portion that are in communication, the air inlet portion including an air inlet opening capable of being in communication with the outside in the blowing mode, and the air outlet portion including an air outlet opening allowing a sucked foreign object to flow outside in the suction mode; and 
     a blowing-suction tube, having a tube opening in communication with the outside to admit or discharge air, where 
     the volute and the blowing-suction tube operably move relative to each other, to enable the blowing suction device to switch between the blowing mode and the suction mode, a rotational axis of the motor output shaft basically coincides with a rotational axis of the fan, in the blowing mode, an extending direction of the motor output shaft is basically consistent with an extending direction of the air inlet portion, and an extending direction of the air outlet portion is perpendicular to the extending direction of the motor output shaft, and in the suction mode, the extending direction of the motor output shaft is basically consistent with an extending direction of the blowing-suction tube, and the extending direction of the air outlet portion is perpendicular to the extending direction of the motor output shaft. 
     In one of the embodiments, the fan includes an air inlet side perpendicular to the motor output shaft and an air outlet side parallel to the motor output shaft, and in the blowing mode, the air inlet opening is located right above the air inlet side. 
     In one of the embodiments, in the blowing mode, the extending direction of the blowing-suction tube is basically consistent with the extending direction of the air outlet portion. 
     In one of the embodiments, in the suction mode, the tube opening is located right in front of the air inlet opening, and the rotational axis of the motor output shaft, the rotational axis of the fan, and a central axis of the blowing-suction tube basically coincide. 
     In one of the embodiments, in the suction mode, the air outlet opening is located right below the air outlet side of the fan. 
     In one of the embodiments, a cross-sectional area of the air inlet opening in a direction perpendicular to an air inlet direction is greater than a cross-sectional area of the air outlet opening in a direction perpendicular to an air outlet direction. 
     In one of the embodiments, the blowing suction device includes a body at least partially covering the airflow generation apparatus, the body includes a holding portion to be held by an operator and a main unit housing connected to the holding portion, the main unit housing is provided with an opening in communication with the outside, in the blowing mode, the opening is in fluid communication with the air inlet portion, and the volute is rotatably mounted in the main unit housing by a rotational axis A. 
     In one of the embodiments, the air outlet portion and the air inlet portion of the volute are disposed at 90 degrees from each other around the rotational axis A. 
     In one of the embodiments, in the blowing mode, the motor body is located below the rotational axis A, and in the suction mode, the motor output shaft and the rotational axis A are approximately located at the same height. 
     In one of the embodiments, the blowing suction device includes a collection apparatus detachably connected to the air outlet portion and used for collecting a foreign object flowing inside from the tube opening of the blowing-suction tube, and the collection apparatus is located below the body. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, and a blowing-suction switching mechanism operably drives the volute to rotate around the rotational axis A relative to the main unit housing, to drive the blowing suction device to be at a blowing position in the blowing mode or a suction position in the suction mode. 
     In one of the embodiments, the blowing-suction switching mechanism includes a toggle, the blowing-suction tube includes a first end near the airflow generation apparatus, and the toggle operably drives the first end of the blowing-suction tube to move between a first position near the airflow generation apparatus and a second position away from the airflow generation apparatus. 
     In one of the embodiments, the blowing-suction switching mechanism further includes an operation component pivotally mounted on the body, and when the blowing-suction tube is at the second position, the operation component operably drives the airflow generation apparatus to rotate to the blowing position or the suction position. 
     In one of the embodiments, the blowing-suction tube is pivotally disposed around a rotational axis A′ relative to the holding portion, and the blowing-suction tube is rotatable between the blowing position and the suction position. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion to be held by an operator; 
     an airflow generation apparatus, connected to the body, and including a motor, a fan driven by the motor to generate an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication with the outside, the air inlet portion includes an air inlet opening capable of being in communication with the outside in the blowing mode, the air outlet portion includes an air outlet opening capable of guiding out a sucked foreign object by the airflow, the fan includes an air inlet side perpendicular to a motor output shaft and an air outlet side parallel to the motor output shaft, and in the blowing mode, an air inlet channel is formed from the air inlet opening to the air inlet side, and an air outlet channel is formed from the air outlet side to a tube opening; and 
     a blowing-suction tube, having the tube opening in communication with the outside to admit or discharge air, and in the suction mode, a dust suction channel being formed from the tube opening to the air inlet side, and a dust discharge channel being formed from the air outlet side to the air outlet opening, where 
     the volute is pivotally disposed relative to the blowing-suction tube, and the volute is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode, to enable the blowing suction device to switch between the blowing mode and the suction mode; 
     when the blowing suction device is in the blowing mode, an extending direction of the air inlet channel is configured to be consistent with an extending direction of the motor output shaft or to be offset clockwise or counterclockwise from an extending direction of the motor output shaft by an angle within a range of 20 degrees; 
     an extending direction of the air outlet channel is configured to be consistent with the extending direction of the motor output shaft or to be offset clockwise or counterclockwise from the extending direction of the motor output shaft by an angle within a range of 20 degrees; 
     when the blowing suction device is in the suction mode, an extending direction of the dust suction channel is configured to be basically consistent with the extending direction of the motor output shaft or to be offset clockwise or counterclockwise from the extending direction of the motor output shaft by an angle within a range of 20 degrees; and 
     an extending direction of the dust discharge channel is configured to be perpendicular to the extending direction of the motor output shaft or to be offset clockwise or counterclockwise from a direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     In one of the embodiments, when the blowing suction device is in the blowing mode, the extending direction of the air inlet channel is capable of being configured to be consistent with the extending direction of the motor output shaft, and the extending direction of the air outlet channel is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft or to be offset counterclockwise or clockwise from the direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     In one of the embodiments, when the blowing suction device is in the blowing mode, the extending direction of the air inlet channel is capable of being configured to be offset clockwise from the extending direction of the motor output shaft by an angle within a range of 20 degrees, and the extending direction of the air outlet channel is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft or to be offset counterclockwise from the direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     In one of the embodiments, when the blowing suction device is in the blowing mode, the extending direction of the air inlet channel is capable of being configured to be offset counterclockwise from the extending direction of the motor output shaft by an angle within a range of 20 degrees, and the extending direction of the air outlet channel is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft or to be offset clockwise or counterclockwise from the direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     In one of the embodiments, when the blowing suction device is in the suction mode, the extending direction of the dust suction channel is configured to be basically consistent with the extending direction of the motor output shaft, and the extending direction of the dust discharge channel is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft or to be offset clockwise or counterclockwise from the direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     In one of the embodiments, when the blowing suction device is in the suction mode, the extending direction of the dust suction channel is configured to be offset clockwise from the extending direction of the motor output shaft by an angle within a range of 20 degrees, and the extending direction of the dust discharge channel is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft or to be offset clockwise from the direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     In one of the embodiments, when the blowing suction device is in the suction mode, the extending direction of the dust suction channel is configured to be offset counterclockwise from the extending direction of the motor output shaft by an angle within a range of 20 degrees, and the extending direction of the dust discharge channel is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft or to be offset clockwise or counterclockwise from the direction perpendicular to the extending direction of the motor output shaft by an angle within a range of 20 degrees. 
     Another objective of the present invention is to provide a single-tube blowing suction device, so that clogging in a suction mode by a foreign object can be effectively reduced. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion to be held by an operator and a main unit housing connected to the holding portion, the main unit housing being provided with an opening in communication with the outside; 
     an airflow generation apparatus, the main unit housing at least partially covering the airflow generation apparatus, the airflow generation apparatus including a motor, a fan driven by the motor and generating an airflow, and a volute surrounding the fan, the motor including a motor body and a motor output shaft extending from the motor body, the volute including an air inlet portion and an air outlet portion that are in communication; and 
     a blowing-suction tube, having a tube opening in communication with the outside to admit or discharge air, where 
     the blowing-suction tube is a single-cavity air tube, the fan is a centrifugal fan, the volute accommodating the centrifugal fan is capable of being pivotally disposed relative to the main unit housing, and the volute is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode; 
     in the blowing mode, an angle formed between an extending direction of the air inlet portion and an extending direction of the blowing-suction tube is a first angle; and in the suction mode, an angle formed between an extending direction of the air outlet portion and the extending direction of the blowing-suction tube is a second angle, and the first angle is equal to the second angle. 
     In one of the embodiments, the centrifugal fan includes an air inlet side perpendicular to the motor output shaft and an air outlet side parallel to the motor output shaft, in the blowing mode, the tube opening is located right in front of the air outlet side, and in the suction mode, the tube opening is located right in front of the air inlet side. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, and the independent integral structure is rotatably mounted on the main unit housing. 
     In one of the embodiments, the blowing suction device includes a collection apparatus detachably connected to the air outlet portion, and the collection apparatus is located right below the body. 
     In one of the embodiments, the air inlet portion includes an air inlet opening in communication with the opening in the blowing mode, the air outlet portion includes an air outlet opening capable of being connected to the collection apparatus in the suction mode, and the air outlet opening and the air inlet opening of the volute are located at 90 degrees from each other around a rotational axis A. 
     In one of the embodiments, in the blowing mode, the motor body is located below the centrifugal fan, and in the suction mode, the motor output shaft and the rotational axis A are approximately located at the same height. 
     In one of the embodiments, a cross-sectional area of the tube opening in a direction perpendicular to an air inlet direction is greater than a cross-sectional area of the air outlet opening in a direction perpendicular to an air outlet direction. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion and a main unit housing connected to the holding portion, the main unit housing being provided with an opening in communication with the outside; 
     an airflow generation apparatus, connected to the main unit housing, the airflow generation apparatus including a motor, a fan driven by the motor and generating an airflow, and a volute surrounding the fan, the motor including a motor body and a motor output shaft extending from the motor body, the volute including an air inlet portion and an air outlet portion that are in communication; and 
     a blowing-suction tube, having a tube opening in communication with the outside to admit or discharge air, where 
     the blowing-suction tube is a single-cavity air tube, the fan is a centrifugal fan, the volute accommodating the centrifugal fan is capable of being pivotally disposed relative to the holding portion, and the volute is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode; 
     in the blowing mode, an angle formed between an extending direction of the air inlet portion and an extending direction of the blowing-suction tube is a first angle; and in the suction mode, an angle formed between an extending direction of the air outlet portion and the extending direction of the blowing-suction tube is a second angle, and the first angle is equal to the second angle. 
     In one of the embodiments, the first angle is 90 degrees. 
     In one of the embodiments, in the suction mode, the motor body, the centrifugal fan, and the blowing-suction tube are sequentially arranged in an axial direction. 
     Another objective of the present invention is to provide a single-tube blowing suction device, so that both the blowing efficiency and suction efficiency can be ensured. 
     To achieve the foregoing objective, the technical solution further adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     an airflow generation apparatus, including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication; 
     a blowing-suction tube, connected to a main unit housing, and having a tube opening in communication with the outside to admit or discharge air, where 
     the air inlet portion includes an air inlet opening in communication with the outside in the blowing mode, and the air outlet portion includes an air outlet opening allowing a sucked foreign object to flow outside; and 
     the fan is a centrifugal fan, the blowing-suction tube is a single-cavity air tube, the blowing-suction tube is provided at a first end near the airflow generation apparatus, the volute and the blowing-suction tube operably move relative to each other, to enable the blowing suction device to switch between the blowing mode and the suction mode, and in the blowing mode, there is a gap between the air outlet opening and the first end to allow an external airflow to enter the blowing-suction tube through the gap. 
     In one of the embodiments, the blowing suction device includes a body disposed around the airflow generation apparatus, the body includes a holding portion and the main unit housing connected to the holding portion, the body is provided with an opening in communication with the outside, and in the blowing mode, the opening is in fluid communication with the air inlet portion. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, the independent integral structure is pivotally disposed relative to the main unit housing and is rotatable between a blowing position in the blowing mode and a suction position in the suction mode, when the airflow generation apparatus rotates to the blowing position, an airflow flows into the volute from the air inlet portion and flows into the blowing-suction tube from the air outlet portion of the airflow generation apparatus, and when the volute rotates to the suction position, an airflow enters an inner cavity of the volute from the tube opening and flows out from the air outlet portion. 
     In one of the embodiments, the first end of the blowing-suction tube and the air outlet portion at least partially overlap in an axial direction. 
     In one of the embodiments, a ratio of a cross-sectional area of the air outlet opening in a direction perpendicular to an air outlet direction to a cross-sectional area of the first end in the direction perpendicular to the air outlet direction is greater than or equal to 1.5 and is less than or equal to 6. 
     In one of the embodiments, the blowing-suction tube has a sectional form and includes a first sub-blowing-suction tube away from the airflow generation apparatus and a second sub-blowing-suction tube near the airflow generation apparatus, and an end, near the airflow generation apparatus, of the second sub-blowing-suction tube forms the first end of the blowing-suction tube. 
     In one of the embodiments, the second sub-blowing-suction tube operably displaces in the axial direction relative to the first sub-blowing-suction tube, the second sub-blowing-suction tube has a first position near the airflow generation apparatus and a second position away from the airflow generation apparatus, and when the second sub-blowing-suction tube is at the second position, the airflow generation apparatus is capable of freely switching between the blowing mode and the suction mode. 
     In one of the embodiments, the blowing suction device further includes a blowing-suction switching mechanism operably driving the airflow generation apparatus to pivot around a rotational axis A relative to the main unit housing. 
     In one of the embodiments, the blowing-suction switching mechanism includes a toggle controlling the second sub-blowing-suction tube to move toward the first position or controlling the second sub-blowing-suction tube to move toward the second position, and the toggle is pivotally connected to the blowing-suction tube. 
     In one of the embodiments, the blowing-suction switching mechanism further includes an operation component pivotally mounted on the body, and when the second sub-blowing-suction tube is at the second position, the operation component operably drives the airflow generation apparatus to be in the blowing position or the suction position. 
     Still another objective of the present invention is to provide a single-tube blowing suction device that is convenient to operate and has improved comfort of human-machine interaction. 
     To achieve the foregoing objective, the technical solution adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion and a main unit housing connected to the holding portion, the main unit housing being provided with an opening in communication with the outside; 
     an airflow generation apparatus, connected to the main unit housing, and including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication; 
     a blowing-suction tube, having a tube opening in communication with the outside to admit or discharge air, where 
     the air inlet portion includes an air inlet opening in fluid communication with the opening in the blowing mode, and the air outlet portion includes an air outlet opening allowing a sucked foreign object to flow outside; and 
     the blowing-suction tube is a single-cavity air tube and is provided with a first end near the volute, the blowing suction device further includes a blowing-suction switching mechanism, the blowing-suction switching mechanism is a linkage apparatus, the linkage apparatus is capable of driving the first end of the blowing-suction tube to be away from the air inlet portion or the air outlet portion of the volute by a preset distance and is capable of linking the volute to rotate relative to the main unit housing to a blowing position in the blowing mode or to a suction position in the suction mode, when the volute rotates from the blowing position to the suction position, the linkage apparatus is capable of linking the first end of the blowing-suction tube to face the air inlet portion, and when the volute switches from the suction mode to the blowing mode, the linkage apparatus is capable of linking the first end of the blowing-suction tube to face the air outlet portion. 
     In one of the embodiments, the linkage apparatus drives the blowing-suction tube to make an axial movement relative to the volute to enable the first end of the blowing-suction tube to be away from the air inlet portion of the volute or the air outlet portion of the volute by the preset distance. 
     In one of the embodiments, when the linkage apparatus links the volute to move relative to the main unit housing to the blowing position, the linkage apparatus is capable of continuing to operate and drive the first end of the blowing-suction tube to displace toward the air outlet portion of the volute by the preset distance. 
     In one of the embodiments, when the linkage apparatus links the volute to move relative to the main unit housing to the suction position, the linkage apparatus is capable of continuing to operate and drive the first end of the blowing-suction tube to displace toward the air inlet portion of the volute by the preset distance, and the first end of the blowing-suction tube is connected to the air inlet portion of the volute in a sealed manner. 
     In one of the embodiments, the airflow generation apparatus is an independent integral structure, and the linkage apparatus is capable of driving the independent integral structure to be rotatable relative to the main unit housing. 
     In one of the embodiments, the linkage apparatus includes a connecting rod, a rotary disk pivotally mounted on the body, and a linkage member fixedly connected to the airflow generation apparatus, the rotary disk is further provided with a convex rod capable of being joined to the linkage member to drive the linkage member to rotate, one end of the connecting rod is pivotally connected to the first end of the blowing-suction tube, and the other end of the connecting rod is pivotally connected to the rotary disk; and 
     the connecting rod and the rotary disk form a crank connecting rod mechanism to convert the rotation of the rotary disk into the axial movement of the blowing-suction tube, and the rotary disk, the convex rod, and the linkage member form a Geneva mechanism, to convert continuous rotation of the rotary disk into intermittent rotation of the airflow generation apparatus relative to the main unit housing through a joint between the connecting rod and the linkage member. 
     In one of the embodiments, the linkage apparatus links the airflow generation apparatus to switch from the blowing mode to the suction mode or from the suction mode to the blowing mode, and a rotational angle of the rotary disk is greater than an angle by which the linkage member links the airflow generation apparatus to rotate. 
     In one of the embodiments, the linkage member includes a first sliding surface and a second sliding surface matching an outer circumferential surface of the rotary disk and an opening groove provided between the first sliding surface and the second sliding surface, when the blowing suction device is in the blowing mode, the outer circumferential surface of the rotary disk faces the first sliding surface, and when the airflow generation apparatus switches to the suction mode, the outer circumferential surface of the rotary disk faces the second sliding surface. 
     In one of the embodiments, the rotary disk rotates and drives the convex rod to switch from being joined to the opening groove to being disengaged from the opening groove, when the first sliding surface of the linkage member slides relative to the outer circumferential surface of the rotary disk, the convex rod is disengaged from the opening groove, the convex rod is joined to the opening groove, and the rotary disk drives the linkage member to rotate circumferentially. 
     In one of the embodiments, when the convex rod is disengaged from the opening groove, the rotary disk is capable of continuing to rotate by the preset distance, and one end of the connecting rod drives the blowing-suction tube to move toward the airflow generation apparatus. 
     In one of the embodiments, the rotary disk includes an anti-rotation plug at least partially protruding from the body, the linkage apparatus further includes an operation component adaptively connected to the anti-rotation plug, and the operation component drives the rotary disk to rotate circumferentially. 
     In one of the embodiments, the operation component includes a hand wheel provided with a concave accommodating cavity and a base accommodated in the accommodating cavity and protruding toward the airflow generation apparatus, the base is provided with an anti-rotation socket matching the anti-rotation plug, the anti-rotation plug is a flat rectangular structure, and the anti-rotation socket is a flat rectangular slot. 
     In one of the embodiments, the linkage apparatus further includes a locking mechanism capable of limiting the airflow generation apparatus at the blowing position or limiting the airflow generation apparatus at the suction position, and the locking mechanism is disposed between the operation component and the main unit housing. 
     In one of the embodiments, the locking mechanism includes a locking member provided with a locking pin, the main unit housing is provided with a slot capable of being locked to the locking pin to lock the blowing suction device in a corresponding working mode, and the operation component operably drives the locking pin to be disengaged from or locked to the slot, to implement switching of the blowing suction device between the blowing mode and the suction mode. 
     In one of the embodiments, the locking mechanism further includes an elastic member disposed between the locking member and the operation component, and the elastic member is capable of applying a restoring force for locking the locking mechanism and the slot. 
     In one of the embodiments, the locking member includes a base portion and a fitting portion disposed on the base portion, the locking pin is located at a free end of the base portion, the operation component is further provided with an action portion capable of fitting the fitting portion, and the action portion is capable of pushing the fitting portion to drive the locking pin to be disengaged from the slot. 
     In one of the embodiments, the operation component includes an exposed pressing portion for pressing, the action portion and the exposed pressing portion are integrally formed, at the same time when an external force is applied to the exposed pressing portion, and the action portion is capable of displacing relative to the main unit housing and pushing the fitting portion, to disengage the slot from the locking pin. 
     In one of the embodiments, a movement direction of the action portion relative to the main unit housing is opposite a movement direction of the fitting portion relative to the main unit housing. 
     In one of the embodiments, an end, facing the action portion, of the fitting portion is formed with an action surface, and the action surface is an inclined slope. 
     In one of the embodiments, as the linkage apparatus drives the volute to rotate, the motor is capable of being in a state of driving the fan to rotate. 
     Yet another objective of the present invention is to provide a single-tube blowing suction device, so that switching between blowing and suction is convenient and a main unit housing has a small volume. 
     To achieve the foregoing objective, the technical solution adopted in the embodiments of the present disclosure is a blowing suction device, having a blowing mode and a suction mode, and including: 
     a body, including a holding portion and a main unit housing connected to the holding portion, the main unit housing being provided with an opening in communication with the outside; 
     an airflow generation apparatus, connected to the main unit housing, and including a motor, a fan driven by an output shaft of the motor and generating an airflow, and a volute surrounding the fan, the volute including an air inlet portion and an air outlet portion in communication, the fan including a hub and several blades arranged in a circumferential direction of the hub; and 
     a blowing-suction tube, connected to the body, and having a tube opening in communication with the outside to admit or discharge air, the blowing-suction tube being provided at a first end near the airflow generation apparatus, where 
     the main unit housing at least partially covers the volute, the volute is pivotally disposed relative to the main unit housing and is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode, the largest distance between a rotational center of the fan and an inner wall of the volute is L 1 , a distance between the rotational center of the fan and an edge of a blade is L 2 , and a ratio of the distance L 1  to the distance L 2  is greater than or equal to 1.2 and is less than or equal to 2. 
     In one of the embodiments, the ratio of the distance L 1  to the distance L 2  is greater than or equal to 1.8 and is less than or equal to 2. 
     In one of the embodiments, in an extending direction of a rotational axis of the fan, the largest distance between two opposite inner walls of the volute is W 1 , the height of the fan is W 2 , and a ratio of the largest distance W 1  to the height W 2  is greater than 1. 
     In one of the embodiments, the volute includes a spiral portion, a throat portion, and a volute tongue formed between a starting end of the spiral portion and the throat portion, and a ratio of the smallest distance between the volute tongue and the edge of the blade close to the volute tongue to the diameter of the fan is 0.08 to 0.12. 
     In one of the embodiments, the ratio of the smallest distance between the volute tongue and the edge of the blade close to the volute tongue to the largest distance L 1  between the rotational center of the fan and the inner wall of the volute is greater than or equal to 0.06. 
     In one of the embodiments, the fan is a centrifugal fan. 
     In one of the embodiments, the air outlet portion includes an air outlet opening allowing a sucked foreign object to flow outside, and in the blowing mode, there is a gap for an external airflow to enter the blowing-suction tube between the air outlet opening and the first end. 
     In one of the embodiments, a ratio of a cross-sectional area of the air outlet opening in a direction perpendicular to an air outlet direction to a cross-sectional area of the first end in the direction perpendicular to the air outlet direction is greater than or equal to 1.5 and is less than or equal to 6. 
     In one of the embodiments, a ratio of a cross-sectional area of the air outlet opening in a direction perpendicular to an air outlet direction to a cross-sectional area of the first end in the direction perpendicular to the air outlet direction is greater than or equal to 3 and is less than or equal to 5. 
     In the single-tube blowing suction device of the present invention, one tube is used for both blowing and suction. It is not necessary to detach and change a blowing tube and a suction tube to switch between blowing and suction. It is only necessary to rotate the airflow generation apparatus relative to the body by a particular angle to implement switching between blowing and suction. The human-machine interaction is desirable, so that the use comfort of a user is improved, and the use efficiency of the user is improved. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  shows a single-tube blowing suction device according to the present invention, the single-tube blowing suction device being in a vacuum mode; 
         FIG. 1B  shows a single-tube blowing suction device according to the present invention, the single-tube blowing suction device being in a blowing mode; 
         FIG. 2A  shows a connection manner between an air inlet portion of a volute and a blowing-suction tube of the single-tube blowing suction device in  FIG. 1 . 
         FIG. 2B  shows a connection manner between an air outlet portion of a volute and a blowing-suction tube of the single-tube blowing suction device in  FIG. 1 . 
         FIG. 3A  and  FIG. 3B  show a single-tube blowing suction device according to the present invention, where a partial structure is omitted to show a linkage apparatus. 
         FIG. 4A  to  FIG. 4F  show an action process of a linkage apparatus according to the present invention. 
         FIG. 5  shows a partial structure of a body of a single-tube blowing suction device according to a second embodiment of the present invention. 
         FIG. 6A  to  FIG. 6C  show a schematic diagram of a switching assisting apparatus according to a third embodiment of the present invention. 
         FIG. 7  is a sectional view of a volute according to a fourth embodiment of the present invention. 
         FIG. 8A  and  FIG. 8B  show a single-tube blowing suction device according to a fifth embodiment of the present invention, where in  FIG. 8A , the single-tube blowing suction device is in a suction mode, and in  FIG. 8B , the single-tube blowing suction device is in a blowing mode. 
         FIG. 9  is a sectional view of a partial structure of a blowing suction device in a blowing mode according to a first embodiment of the present invention. 
         FIG. 10  is a partial sectional view after a linkage apparatus in the first embodiment of the present invention driving an airflow generation apparatus to rotate by 90 degrees. 
         FIG. 11  is a partial exploded view of a blowing suction device with a blowing-suction tube and a power supply apparatus removed according to the present invention. 
         FIG. 12  is a three-dimensional schematic diagram of an operation button and a locking mechanism according to a first embodiment of the present invention. 
         FIG. 13  is a three-dimensional schematic diagram of the operation button and the locking mechanism shown in  FIG. 12  from another perspective. 
         FIG. 14  is a partial exploded view of an operation component and a locking mechanism shown in  FIG. 12 . 
         FIG. 15  is a schematic diagram of the partial exploded view shown in  FIG. 14  from another perspective. 
         FIG. 16  is a partial three-dimensional schematic diagram of the structure shown in  FIG. 12 . 
         FIG. 17  is a rear view of a blowing suction device in a blowing mode according to a third embodiment of the present invention. 
         FIG. 18  is a partial enlarged view of the circled part in  FIG. 17 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Exemplary embodiments of the present invention are described below in detail with reference to the accompanying drawings. It should be understood that these specific descriptions are merely used for teaching a person skilled in the art to implement the present invention, but are not used to exhaust all possible manners of the present invention and are not used for limiting the scope of the present invention. 
     First Embodiment 
     An overall structure of a single-tube blowing suction device according to the first embodiment of the present invention is first described. 
     As shown in  FIG. 1A  and  FIG. 1B , the first embodiment of the present invention provides a single-tube blowing suction device (sometimes referred to as a “blowing suction device” for short)  100  for cleaning fallen leaves and twig pieces in a garden, including a body  1 , a blowing-suction tube  2 , and an airflow generation apparatus  3 . Specifically, the blowing suction device  100  may use a blowing function to gather scattered leaves or may use a suction function to suck leaves into a specified garbage collection apparatus to implement cleaning. Therefore, the blowing suction device  100  has at least following two working modes. When the blowing suction device  100  is in a first working mode, the blowing suction device  1  performs the blowing function, and when the blowing suction device  100  is in a second working mode, the blowing suction device  1  performs the suction function. Therefore, the first working mode may also be referred to as a blowing mode (referring to  FIG. 1B ), and the second working mode may also be referred to as a suction mode (referring to  FIG. 1A ). The blowing suction device  100  may selectively work in the blowing mode or the suction mode according to an actual requirement of a user. 
     The blowing suction device  100  generally extends in a direction shown by an arrow X in  FIG. 1A  and  FIG. 9 . The direction is defined as an axial direction. Further, in the present invention, for ease of understanding, as shown in  FIG. 1A  and  FIG. 9 , in the axial direction, a side, away from the airflow generation apparatus  3 , of the blowing-suction tube  2  is defined as front, the opposite side is defined as rear, the above in the drawings is defined as above, and the below in the drawings is defined as below. Reference may be made to  FIG. 17  for the left side and the right side, and the foregoing definitions are only used for description, and should not be understood as a limitation to the present invention. 
     As shown in  FIG. 1  to  FIG. 4  and  FIG. 9  to  FIG. 11 , the body  1  includes a grip portion (handle)  11  and a main unit housing  10  connected to the holding portion  11 . The grip portion  11  and the main unit housing  10  may be integrally disposed, and certainly may be separately disposed. The main unit housing  10  is provided with a blowing-suction tube connecting portion  12  and a body air inlet portion  13 . In the example shown in the figures, the body air inlet portion  13  is near the grip portion  11 , and the body air inlet portion  13  includes an opening  130  in communication with the outside. A first end  21  of the blowing-suction tube  2  is mounted at the blowing-suction tube connecting portion  12 , and a second end of the blowing-suction tube  2  is opposite the first end  21  in the axial direction and is formed with a tube opening  22  for air flowing into and flowing out. As shown in  FIG. 1A  and  FIG. 1B , the tube opening  22  preferably tilts relative to an extending direction (a central axis) of the blowing-suction tube  2 . That is, a plane in which the tube opening  22  is located is not perpendicular to the extending direction of the blowing-suction tube  2 . In the example shown in the figures, the blowing-suction tube  2  is a straight tube. However, the present invention is not limited thereto. One or more positions of the blowing-suction tube  2  may have a particular radian. 
     Referring to  FIG. 1A  and  FIG. 1B ,  FIG. 2A  and  FIG. 2B , and  FIG. 9  to  FIG. 11 , the airflow generation apparatus  3  is at least partially exposed on an outer side of the body  1 . Specifically, the main unit housing  10  is provided with a front-end opening  101  and a rear-end opening  102  penetrating in a longitudinal direction. The airflow generation apparatus  3  at least partially extends backward and is exposed from an outer side of the rear-end opening  102 . The airflow generation apparatus  3  includes a motor  31 , a fan  32  connected to the motor  31 , and a volute  33  surrounding the fan  32 . The motor  31  includes a motor body  311  and a motor output shaft  312  extending from the motor body  311 . A rotational axis of the motor output shaft  312  basically coincides with a rotational axis of the fan  32 . In an embodiment, the volute  33  may be fixedly connected to or integrally formed with a motor cylinder (a motor housing  313  covering the motor  31 ) of the motor  31 , so that the entire airflow generation apparatus  3  is an independent integral structure. Certainly, the volute and the motor housing  313  may be separately disposed. The volute  33  includes an air inlet portion (an air inlet tube)  331  and an air outlet portion (an air outlet tube)  332  in communication with the outside. The air inlet portion  331  includes an air inlet opening  3310  capable of being in fluid communication with the opening  130  in the blowing mode, and the air inlet opening  3310  is disposed facing the grip portion  11 . Preferably, the opening  130  is located right above the air inlet opening  3310 , so that an airflow directly enters the air inlet portion  331  without turning. The air outlet portion  332  includes an air outlet opening  3320  capable of being connected to the collection apparatus in the suction mode. A foreign object sucked into the blowing-suction tube  2  can pass through the fan  32 , and flows into the collection apparatus through the air outlet opening  3320 . It should be noted that “fluid communication” should be understood as that gas can flow between two openings. 
     As shown in  FIG. 9  and  FIG. 10 , the fan  32  may be a double-layer vane structure. A main blade is disposed on one side of a hub of the fan, and an auxiliary blade is disposed on the other side of the hub of the fan. The auxiliary blade is mainly used for cooling the motor, and the main blade is mainly used for implementing the blowing function. Specifically, in this embodiment, as shown in  FIG. 9  and  FIG. 10 , the fan  32  used in the single-tube blowing suction device  100  provided in the present invention is a centrifugal fan. The fan  32  includes a hub  321  and several blades  322  disposed circumferentially around the hub  321 . When the centrifugal fan  32  is driven by the motor  31  to rotate, air filled between the blades of the centrifugal fan  322  is pushed by the blades  322  and is thrown to outer edges of the blades under the effect of a centrifugal force. After the pressure energy and kinetic energy of the air are increased, air flows out from the outer edges of the blades  322 , and a negative pressure is formed in the middle of the blades  322 , so that air is continuously sucked in and discharged to generate an axial suction force and a radial blowing force. Particularly, when the blowing suction device  100  is in the suction mode, and when a housing part around the centrifugal fan  32  is blocked by miscellaneous objects such as leaves, in this case, the centrifugal fan  32  may generate a larger output suction force, making it easy to suck out and discharge blocked leaves. Referring to  FIG. 9  and  FIG. 10 , the centrifugal fan  32  has an air inlet side  323  perpendicular to the motor output shaft  312  and an air outlet side  324  parallel to the motor output shaft  312 . In the blowing mode, an air entering channel Q 1  is formed from the air inlet opening  3310  to the air inlet side  323 , and an air discharging channel Q 2  is formed from the air outlet side  324  to the tube opening  22 . In the suction mode, a dust suction channel Q 3  is formed from the tube opening  22  to the air inlet side  323 , and a dust discharging channel Q 4  is formed from the air outlet side  324  to the air outlet opening  3320 . 
     In the present invention, the volute  33  and the blowing-suction tube  2  operably move relative to each other, to enable the blowing suction device  100  to switch between the blowing mode and the suction mode. In a feasible embodiment, the air entering channel Q 1  and the dust suction channel Q 3  may be designed to be offset clockwise or counterclockwise from the motor output shaft  312  by a particular preset angle. The air discharging channel Q 2  and the dust discharging channel Q 4  may be designed to be offset clockwise or counterclockwise from a direction perpendicular to the motor output shaft  312  by a particular preset angle. Specifically, when the blowing suction device  100  is in the blowing mode, an extending direction of the air entering channel Q 1  is configured to be consistent with an extending direction of the motor output shaft  312  or to be offset clockwise or counterclockwise from the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees, and an extending direction of the air discharging channel Q 2  is configured to be perpendicular to the extending direction of the motor output shaft  312  or to be offset clockwise or counterclockwise from a direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. When the blowing suction device  100  is in the suction mode, an extending direction of the dust suction channel Q 3  is configured to be basically consistent with the extending direction of the motor output shaft  312  or to be offset clockwise or counterclockwise from the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees, and an extending direction of the dust discharging channel Q 4  is configured to be perpendicular to the extending direction of the motor output shaft  312  or to be offset clockwise or counterclockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. 
     Specifically, in some embodiments, when the blowing suction device  100  is in the blowing mode, the extending direction of the air entering channel Q 1  can be configured to be consistent with the extending direction of the motor output shaft  312 . In addition, the extending direction of the air discharging channel Q 2  may be configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset counterclockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees or to be offset clockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. Preferably, the extending direction of the air discharging channel Q 2  is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset counterclockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 10 degrees or to be offset clockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 10 degrees. 
     When the blowing suction device  100  is in the blowing mode, the extending direction of the air entering channel Q 1  can be configured to be offset counterclockwise from the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees, and the extending direction of the air discharging channel Q 2  is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset counterclockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees or to be offset clockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. 
     When the blowing suction device  100  is in the blowing mode, the extending direction of the air entering channel Q 1  can be configured to be offset clockwise from the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees, and the extending direction of the air discharging channel Q 2  is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset clockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. 
     When the blowing suction device  100  is in the suction mode, the extending direction of the dust suction channel Q 3  is configured to be basically consistent with the extending direction of the motor output shaft  312 , and the extending direction of the dust discharging channel Q 4  is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset clockwise or counterclockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. 
     When the blowing suction device  100  is in the suction mode, the extending direction of the dust suction channel Q 3  is configured to be offset clockwise from the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees, and the extending direction of the dust discharging channel Q 4  is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset clockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. 
     When the blowing suction device  100  is in the suction mode, the extending direction of the dust suction channel Q 3  is configured to be offset counterclockwise from the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees, and the extending direction of the dust discharging channel Q 4  is configured to be consistent with the direction perpendicular to the extending direction of the motor output shaft  312  or to be offset counterclockwise or clockwise from the direction perpendicular to the extending direction of the motor output shaft  312  by an angle within a range of 20 degrees. 
     It can be easily understood that in the blowing mode, the extending direction of the air entering channel Q 1  is offset clockwise or counterclockwise from the extending direction of the motor output shaft  312  by an angle within a particular preset range, and the extending direction of the air discharging channel Q 2  is offset clockwise or counterclockwise from the extending direction of the motor output shaft by an angle within a particular range. With such a configuration, in the blowing mode, the blowing efficiency can meet a requirement. 
     In the suction mode, the extending direction of the dust suction channel Q 3  is offset clockwise or counterclockwise from the extending direction of the motor output shaft  312  by an angle within a preset range, and the extending direction of the dust discharging channel Q 4  is offset clockwise or counterclockwise from the extending direction of the motor output shaft by an angle within a particular range. With such a configuration, in the suction mode, the suction efficiency can also meet a requirement. 
     Preferably, in the examples shown in  FIG. 1A  to  FIG. 2B ,  FIG. 9 , and  FIG. 10 , in the blowing mode, the extending direction of the motor output shaft  312  is consistent with an extending direction of the air inlet portion  331 , and an extending direction of the air outlet portion  332  is perpendicular to the extending direction of the motor output shaft  312 . In the suction mode, the extending direction of the motor output shaft  312  is consistent with the extending direction of the blowing-suction tube  2 , and the extending direction of the air outlet portion  332  is perpendicular to the extending direction of the motor output shaft  312 . Specifically, as shown in  FIG. 1A  to  FIG. 2B ,  FIG. 9 , and  FIG. 10 , in the blowing mode, the air inlet opening  3310  is located right above the air inlet side  323  of the fan  32 , and the air outlet opening  3320  is located right in front of the air outlet side  324 . An extending direction of the blowing-suction tube  2  is consistent with the extending direction of the air outlet portion  332 . In the suction mode, the tube opening  22  is located right in front of the air inlet opening  3310 , the air inlet opening  3310  is located right in front of the air inlet side  323 , and the rotational axis of the motor output shaft  312 , the rotational axis of the fan  32 , and the central axis of the blowing-suction tube  2  basically coincide. The air outlet opening  3320  is located right below the air outlet side  324  of the fan  32 . In this way, an airflow directly enters and leaves. In one aspect, in the blowing mode, an airflow loss caused by a bend is reduced, thereby improving a blowing effect. In another aspect, in the suction mode, blocking by a sucked object is reduced, thereby improving the suction efficiency. 
     For operable relative movement of the volute  33  and the blowing-suction tube  2 , in a feasible embodiment, as shown in  FIG. 1A  to  FIG. 4D ,  FIG. 9 , and  FIG. 11 , the volute  33  rotates to switch between blowing and suction. Specifically, the volute  33  is pivotally disposed relative to the grip portion  11  or the main unit housing  10 , and is at least rotatable between a blowing position in the blowing mode and a suction position in the suction mode. When the volute  33  rotates to the blowing position (referring to  FIG. 1B ,  FIG. 2B ,  FIG. 3B , and  FIG. 9 ). An airflow passes through the opening  130  of the main unit housing  10  and enters the volute  33  through the air inlet portion  331 , and flows into the blowing-suction tube  2  from the air outlet portion  332  of the volute  33 . When the volute  33  rotates to the suction position (referring to  FIG. 1A ,  FIG. 2A ,  FIG. 3A , and  FIG. 10 ), an airflow enters the volute  33  from the tube opening  22  and flows out from the air outlet portion  332 . An opening direction of the opening  130  of the air inlet portion  13  is disposed opposite an opening direction of the air outlet portion  332 . 
     In this embodiment, as shown in  FIG. 9  and  FIG. 10 , the grip portion  11  extends longitudinally along a first axis Y, and the blowing-suction tube  2  extends longitudinally along a second axis Z. When the volute  33  rotates to switch between the blowing mode and the suction mode, an angle formed between the first axis Y and the second axis Z remains unchanged. It should be noted that when the first axis Y and the second axis Z are disposed to be parallel to each other, the angle is zero degrees. The blowing-suction tube  2  is a single-cavity air tube. When the blowing suction device  100  is in the blowing mode or the suction mode, the extending direction of the blowing-suction tube  2  remains unchanged. With such a design, in the blowing mode and the suction mode, only the volute  33  rotates, and a mounting direction of the blowing-suction tube  2  does not change. In other words, an angle between the blowing-suction tube  2  and the body  1 /the grip portion  11  does not change. During switching between blowing and suction, it is only necessary to rotate the volute  33 , and postures or directions of the body  1  (the grip portion  11 ) and the blowing-suction tube  2  are kept unchanged. An operator does not need to adjust a holding manner, and the blowing suction device  100  remains in the form of single-handed operation. This simplifies the operation during switching between blowing and suction, so that the design difficulty in the aspect of human-machine interaction of the blowing suction device is reduced, making it convenient for the operator to hold the machine for cleaning. 
     Further, when the volute  33  rotates to the blowing position, the air outlet opening  3320  faces the first end of the blowing-suction tube  2 , and an angle formed between the extending direction of the air inlet portion  331  and the extending direction of the blowing-suction tube  2  is a first angle α (as shown in  FIG. 9 ). Further, when the volute  33  rotates to the suction position, the air inlet opening  3310  is joined to and in communication with the first end of the blowing-suction tube  2 , and the angle formed between the extending direction of the air outlet portion  332  and the extending direction of the blowing-suction tube  2  is a second angle β (as shown in  FIG. 10 ). The “the air outlet opening  3320  faces the first end of the blowing-suction tube  2 ” may be understood as that a fully sealed connection or a non-fully sealed connection may be designed between the air outlet opening  3320  and the blowing-suction tube  2 . The first angle a is equal to the second angle β. The first angle α and the second angle β may be 70 degrees to 110 degrees. Preferably, the first angle α and the second angle β may both be 90 degrees. It is easily understood that the air outlet portion  332  and the air inlet portion  331  are disposed around a rotational axis A at 70 degrees to 110 degrees from each other. Alternatively, the air outlet opening  3320  and the air inlet opening  3310  are disposed around the rotational axis A at 70 degrees to 110 degrees from each other, and preferably at an angle of 90 degrees from each other. 
     Further, it is easily understood that referring to the blowing suction device  100  in the figure, an angle between an extending direction X 1  of the motor output shaft  312  in the blowing mode and an extending direction X 2  of the motor output shaft  312  in the suction mode is 70 degrees to 110 degrees. Preferably, the angle is 90 degrees, and the volute  33  rotates counterclockwise or clockwise around the rotational axis A by 70 degrees to 110 degrees relative to the main unit housing  10 , so that the blowing suction device  100  is in the blowing mode or the suction mode. Preferably, a rotational angle of the volute  33  is 90 degrees. 
     In the embodiments of the present disclosure, the blowing suction device  100  uses the same blowing-suction tube  2  in the blowing mode and the suction mode. Therefore, it is not difficult to understand that in the blowing suction device  100  in the embodiments of the present disclosure, an air opening through which an airflow flows out in the blowing mode and an air opening through which an airflow enters carrying a foreign object (such as leaves or twigs) in the suction mode are the same air opening, that is, the tube opening  22 . To ensure that relatively large foreign objects such as leaves or twigs smoothly pass through the tube opening  22  to enter the blowing-suction tube  2 . A cross-sectional area of the tube opening  22  in a direction perpendicular to an air inlet direction is not less than a cross-sectional area of the air outlet opening  3320  in a direction perpendicular to an air outlet direction. Preferably, the cross-sectional area of the tube opening  22  in the direction perpendicular to the air inlet direction is greater than the cross-sectional area of the air outlet opening  3320  in the direction perpendicular to the air outlet direction. In this way, with the design of the tube opening  22  with a relatively large cross-section, in one aspect, in the suction mode, a relatively large foreign object is less likely to fail to pass through the tube opening  22  to enter the blowing-suction tube  2  or a relatively large foreign object is less likely to block the tube opening  22 . In another aspect, with the design of the air outlet opening  3320  with a relatively small cross-section, a flow speed of an air flow can be increased. 
     In this implementation, the airflow generation apparatus  3  is an independent integral structure. The independent integral structure is rotatably mounted on the body  1 . That is, when the blowing suction device  100  switches between the blowing mode and the suction mode, the airflow generation apparatus  3  provided with the motor  31  and the fan  32  generally rotates relative to the main unit housing  10 . Therefore, when the blowing suction device  100  switches between the blowing position and the suction position, it may be not necessary to stop the operation of the motor  31  and the fan  32 . A user may directly switch between blowing and suction while the motor  31  and the fan  32  are in a working state. That is, when the blowing suction device  100  switches between the blowing mode and the suction mode, the motor  31  can be still relative to the fan  32 , and the motor  31  rotates relative to the body  1 . Preferably, in the example shown in the figure, the airflow generation apparatus  3  rotates around the body  1  by 90 degrees to switch between blowing and suction. When the air inlet portion  331  of the airflow generation apparatus  3  rotates to be vertically upward (aligned with the body air inlet portion  13 ), the blowing mode is disposed. When the air inlet portion  331  rotates to the right (aligned with the first end  21  of the blowing-suction tube  2 ), the suction mode is disposed. In the blowing mode (for example, referring to  FIG. 1A ), the motor body  311  is located on a rear side of the centrifugal fan  32 , and the output shaft of the motor  31  is parallel to the central axis of the blowing-suction tube  2 . In the suction mode (for example, referring to  FIG. 1B ), the motor body  311  is located below the centrifugal fan  32 , and the output shaft  312  of the motor  31  is perpendicular to the central axis of the blowing-suction tube  2 . The rotational axis A is located below the grip portion  11  and passes through the geometric center of the volute  33 . 
     It should be understood that an angle by which the airflow generation apparatus (the volute  33 ) rotates during switching from the blowing mode to the suction mode or from the suction mode to the blowing mode is determined by using an angle formed between the air inlet portion  331  and the air outlet portion  332  of the volute  33  around the rotational axis A. The angle is not limited to the 90 degrees described above. For example, the angle may be 90 degrees±20 degrees. 
     The inventor finds through experiment that compared with the comparison example in which the volute is not rotatable and the blowing-suction tube is separately disposed, both the blowing efficiency and the suction efficiency of the single-tube blowing suction device in this embodiment are improved by more than 20%. 
     In the single-tube blowing suction device  100  in this embodiment, for example, compared with the solution in which a blowing tube and a suction tube are changed, it is only necessary to rotate the volute  33  to implement switching between blowing and suction. Therefore, this embodiment significantly improves human-machine use comfort. 
     Further, the single-tube blowing suction device  100  may further include a garbage bag  7  connected to the body  1  which is used as an example of the collection apparatus. Specifically, the garbage bag  7  is connected to the air outlet portion  332 , is located below the body  1 , and is used for collecting a foreign object entering from the tube opening  22  of the blowing-suction tube  2 . The garbage bag  7  is at least partially made of an air-permeable material and is used for accommodating debris such as leaves sucked in from the blowing-suction tube  2 . The garbage bag  7  includes a main body  71 , a strap  72 , and a connection port  73  used for connecting to the air outlet portion  332  of the volute  33 . The single-tube blowing suction device  100  may further include a power plug  4  and is powered by an alternating-current power. However, the present invention is not limited thereto. The single-tube blowing suction device  100  may further be powered by a direct-current power, for example, a lithium battery. 
     A manner of implementing switching between blowing and suction of the single-tube blowing suction device  100  according to this implementation is described below. 
     As shown in  FIG. 1A , when the air inlet portion  331  of the volute  33  is connected to the first end  21  of the blowing-suction tube  2  and the air outlet portion  332  of the volute  33  is connected to the connection port  73  of the garbage bag  7 , the single-tube blowing suction device  100  is in the suction mode. The fan  32  rotates in the volute  33 . The rotation of the fan  32  draws an external airflow into the volute  33  through the blowing-suction tube  2 . The external airflow is guided in the volute  33  to blow into the garbage bag  7  from the air outlet portion  332 . Debris sucked by the airflow is collected in the garbage bag  7 . 
     In the suction mode shown in  FIG. 1A , the airflow generation apparatus  3  (the volute  33 ) rotates in the direction indicated by an arrow P 1  relative to the body  1  and the blowing-suction tube  2  by 90 degrees to enable the single-tube blowing suction device  100  to enter the blowing mode. 
     As shown in  FIG. 1B , in the blowing mode, the air inlet portion  331  of the volute  33  is in fluid communication with the body air inlet portion  13  of the body  1 , and the air outlet portion  332  of the volute  33  is in fluid communication with the first end  21  of the blowing-suction tube  2 . The fan  32  rotates in the volute  33 . The rotation of the fan  32  draws an external airflow into the volute  33  through the body air inlet portion  13 . The external airflow is guided in the volute  33  to blow into the blowing-suction tube  2  from the air outlet portion  332  and is blown out from the second end  22  of the blowing-suction tube  2 . 
     In the blowing mode shown in  FIG. 1B , the airflow generation apparatus (the volute  33 ) rotates in the direction indicated by an arrow P 2  relative to the body  1  and the blowing-suction tube  2  by 90 degrees to enable the single-tube blowing suction device  100  to enter the suction mode. As shown in  FIG. 1A  and  FIG. 1B , the arrows P 1  and P 2  have opposite directions. 
     To implement that the airflow generation apparatus  3  rotates relative to the body  1 , the blowing suction device  100  further includes a blowing-suction switching mechanism, and the blowing-suction switching mechanism operably drives the volute  33  to rotate around the rotational axis A between the blowing position in the blowing mode and the suction position in the suction mode. Specifically, when the volute  33  rotates from the blowing position to the suction position, the blowing-suction switching mechanism can drive the first end  21  of the blowing-suction tube  2  to be joined to and in communication with the air inlet portion  331 . When the volute  33  rotates from the suction position to the blowing position, the blowing-suction switching mechanism can drive the first end  21  of the blowing-suction tube  2  to face the air outlet portion  332 . 
     As shown in  FIG. 11  and  FIG. 17 , to enable a user to operate the volute  33  to rotate relative to the body  1  and the blowing-suction tube  2 , the blowing-suction switching mechanism includes an operation component  5  that may connect the rotational axis A of the volute  33  and is used as an example of a rotation driving portion. The operation component  5  drives the volute  33  to rotate relative to the body  1  and the blowing-suction tube  2 . It should be understood that the motor  31  and the volute  33  may be completely or partially accommodated in the housing of the body  1 , provided that the operation component  5  is exposed. It should be noted that the operation component herein may be understood as an operation button in an example. 
     The blowing-suction switching mechanism and action processes of the blowing-suction tube and the volute in a first embodiment are described below. 
     In this embodiment, as shown in  FIG. 1A  and  FIG. 1B , the blowing-suction switching mechanism includes a toggle  9 . When the blowing suction device  100  switches from the suction mode to the blowing mode, the toggle controls the first end  21  of the blowing-suction tube  2  to be disengaged from the air inlet portion  331 , and the operation component drives the volute  33  to rotate relative to the main unit housing  10  to the blowing position. When the blowing suction device  100  switches from the blowing mode to the suction mode, the toggle  9  controls the first end  21  of the blowing-suction tube  2  to be disengaged from the air outlet portion  332 , and the operation component  5  drives the volute  33  to rotate relative to the main unit housing  10  to the suction position. 
     Specifically, as shown in  FIG. 1A  and  FIG. 1B , the central position of the toggle  9  is pivotally mounted on the body  1  by a pivotal shaft  14 . A long hole  91  is formed at the first end of the toggle  9 , and a pivotal shaft  23  extending from a sidewall of the blowing-suction tube  2  is inserted in the long hole  91 . A second end of the toggle  9  is exposed from the body  1 . In this way, the second end of the toggle  9  may be pushed to enable the toggle  9  to rotate around the pivotal shaft  14 , so as to drive the first end  21  of the blowing-suction tube  2  to move between a first position near the airflow generation apparatus  3  and a second position away from the airflow generation apparatus (volute  33 ). 
     For example, during switching from the suction mode in  FIG. 1A  to the blowing mode in  FIG. 1B , first, the second end of the toggle  9  is pulled to enable the first end  21  of the blowing-suction tube  2  to move away from the volute  33  to be detached from the air inlet portion  331  of the volute  33  (that is, the blowing-suction tube  2  is located at the second position). Next, the rotation of the operation component  5  is used to rotate the airflow generation apparatus (volute  33 ), to enable the air outlet portion  332  of the volute  33  to be aligned with the first end  21  of the blowing-suction tube  2 . Finally, the second end of the toggle  9  is pushed to enable the first end  21  of the blowing-suction tube  2  to move toward the volute  33  to face the air outlet portion  332  of the volute  33 . 
     In this embodiment, at least a part of the blowing-suction tube  2  is slidably connected to the blowing-suction tube connecting portion  12  of the body  1 . Specifically, a channel for an airflow to flow through is provided in an inner cavity of the blowing-suction tube  2 . In an example, the blowing-suction tube  2  may be one blowing-suction tube  2  that is formed of a plurality of sections and has a complete blowing function or suction function. Referring to  FIG. 9  and  FIG. 10 , the blowing-suction tube  2  includes a first sub-blowing-suction tube  26  away from the airflow generation apparatus  3  and a second sub-blowing-suction tube  27  near the airflow generation apparatus  3 . The second sub-blowing-suction tube  27  operably displaces in an axial direction. The second sub-blowing-suction tube  27  has the first position near the airflow generation apparatus  3  and the second position away from the airflow generation apparatus  3 . The toggle  9  controls the second sub-blowing-suction tube  27  to move toward the first position or controls the second sub-blowing-suction tube  27  to move toward the second position. It is easily understood that when the blowing suction device  100  switches between the blowing mode and the suction mode, the first sub-blowing-suction tube  26  does not displace relative to the body  1 , and only the second sub-blowing-suction tube  27  is slidably connected to the blowing-suction tube connecting portion of the body  1 . In other words, in this embodiment, when the blowing suction device  100  is in the blowing mode or the suction mode, an axial distance between the foremost end (which may be understood as the foremost end of the tube opening  22 ) of the blowing-suction tube  2  and the rotational axis A remains unchanged. More specifically, in the blowing mode, when the second sub-blowing-suction tube  27  is at the first position, the second sub-blowing-suction tube  27  faces the air outlet portion  332 . In the suction mode, when the second sub-blowing-suction tube  27  is at the first position, the second sub-blowing-suction tube  27  is connected to the air inlet portion  331 . 
     It should be noted that the second sub-blowing-suction tube  27  herein may also be understood as an independent structure rather than a part of the blowing-suction tube  2 . For example, in some embodiments, the blowing-suction tube  2  may be alternatively fixedly connected to the body  1 . The body further includes an adaptation portion (not shown in the figure). The adaptation portion is connected to the blowing-suction tube  2  and is movable relative to the blowing-suction tube  2  between the first position near the airflow generation apparatus (the volute  33 ) and the second position away from the airflow generation apparatus (the volute  33 ). The adaptation portion may be driven by a structure similar to the toggle  9 . An example in which the toggle  9  drives the adaptation portion to move at different positions is used for detailed description below. In the suction mode, the air inlet portion  331  of the volute  33  is sleeved over the adaptation portion to implement sealing. In the blowing mode, the air outlet portion  332  of the volute  33  is clamped to the adaptation portion, to inhibit the shaking of the blowing-suction tube  2 . During switching from the suction mode to the blowing mode, the adaptation portion is moved toward the second position away from the volute  33  to enable the adaptation portion to be detached from the air inlet portion  331  of the volute  33 . Next, the airflow generation apparatus (the volute  33 ) is rotated to enable the air outlet portion  332  of the volute  33  to be aligned with the adaptation portion. Finally, the second end of the toggle  9  is pushed to enable the adaptation portion to move toward the first position near the volute  33  to be joined to the air outlet portion  332  of the volute  33 . During switching from the blowing mode to the suction mode, the adaptation portion is moved toward the second position away from the volute  33  to enable the adaptation portion to be detached from the air outlet portion  332  of the volute  33 . Next, the airflow generation apparatus (the volute  33 ) is rotated to enable the air inlet portion  331  of the volute  33  to be aligned with the adaptation portion. Finally, the second end of the toggle  9  is pushed to enable the adaptation portion to move toward the first position near the volute  33  to be joined to the air inlet portion  331  of the volute  33 . With such an arrangement, in one aspect, it can be similarly implemented that the airflow generation apparatus (the volute  33 ) is rotated to switch between the blowing mode and the suction mode. In the blowing mode, the fastening between the blowing-suction tube  2  and the air outlet portion  332  of the volute  33  is implemented, to avoid the shaking of the blowing-suction tube  2 . In another aspect, in the suction mode, the sealing between the blowing-suction tube  2  and the air inlet portion  331  of the volute  33  can be similarly implemented, so that a miscellaneous object sucked in the suction mode can smoothly enter into a garbage bag through the blowing-suction tube  2  and the volute  33 . 
     Certainly, when the airflow generation apparatus  3  switches between the blowing mode and the suction mode, the second sub-blowing-suction tube  27  or the adaptation portion may be alternatively directly linked to move from the first position to the second position. A specific structure and a movement process of the linkage are described below in detail. 
     The blowing-suction switching mechanism and action processes of the blowing-suction tube  2  and the volute  33  in a second embodiment are described below with reference to  FIG. 3A  to  FIG. 4F  and  FIG. 11  to  FIG. 19 . 
     In a first embodiment, the rotation of the airflow generation apparatus  3  (the volute  33 ) and an axial movement of the blowing-suction tube  2  are independent of each other. In this embodiment, the blowing-suction switching mechanism is a linkage apparatus  7 . The linkage apparatus  7  can drive the first end  21  of the blowing-suction tube  2  to be away from the air inlet portion  331  or the air outlet portion  332  of the volute  33  by a preset distance, and can link the volute  33  to rotate relative to the main unit housing  10  to the blowing position in the blowing mode or to the suction position in the suction mode. When the volute  33  rotates from the blowing position to the suction position, the linkage apparatus  7  can link the first end  21  of the blowing-suction tube  2  to face the air inlet portion  331 . When the volute  33  switches from the suction mode to the blowing mode, the linkage apparatus  7  can link the first end  21  of the blowing-suction tube  2  face the air outlet portion  332 . 
     It should be noted that in “the linkage apparatus  7  can drive the first end  21  of the blowing-suction tube  2  to be away from the air inlet portion  331  or the air outlet portion  332  of the volute  33  by a preset distance”, the preset distance herein may be understood as that the first end  21  of the blowing-suction tube  2  is completely separated from the air inlet portion  331  or the air outlet portion  332  of the volute  33  or may be understood as that an end surface of the first end  21  of the blowing-suction tube  2  is at least partially attached to an end surface of the air inlet portion  331  or the air outlet portion  332  of the volute  33 , provided that the first end  21  of the blowing-suction tube  2  and the air inlet portion  331  or the air outlet portion  332  of the volute  33  do not overlap in a direction perpendicular to the axial direction. 
     The linkage apparatus  7  links the rotation of the airflow generation apparatus (the volute  33 ) and the axial movement of the blowing-suction tube  2 , thereby simplifying a blowing-suction switching operation. Specifically, the linkage apparatus  7  can drive the first end  21  of the blowing-suction tube  2  to make an axial movement relative to the airflow generation apparatus  3 , and can link the airflow generation apparatus  3  to rotate relative to the body  1  to the blowing position in the blowing mode or to the suction position in the suction mode. In the blowing mode, the linkage apparatus  7  can link the first end  21  of the blowing-suction tube  2  to be in communication connection to the air outlet portion  332 . In the suction mode, the linkage apparatus  7  can link the first end  21  of the blowing-suction tube  2  to be in communication connection to the air inlet portion  331 . As the linkage apparatus  7  drives the airflow generation apparatus  3  to rotate, the motor  31  can be in a state of driving the fan  32  to rotate. 
     In this embodiment, the same reference numerals are marked for the same parts in the first embodiment, and detailed description of these parts is omitted. In addition, for clear description, a partial structure of the single-tube blowing suction device is omitted in  FIG. 3A  and  FIG. 3B . 
     The structure of the linkage apparatus of the volute  33  according to this embodiment is described below with reference to  FIG. 3A  to  FIG. 4F  and  FIG. 11  to  FIG. 19 . 
     The linkage apparatus  7  in this embodiment includes a connecting rod  25 , a rotary disk  16 , and a convex rod  17  and a linkage member  73  that extend from the rotary disk  16 . 
     One end of the connecting rod  25  is connected to the first end  21  of the blowing-suction tube  2  by a pivotal shaft  24 . The pivotal shaft  24  further passes through the body  1 , and in particular, passes through a guide rail (or a guide groove)  15  formed on the blowing-suction tube connecting portion  12 . The guide rail  15  extends in the axial direction of the blowing-suction tube  2  to guide an axial movement of the pivotal shaft  24 . When the pivotal shaft  24  makes an axial movement relative to the guide rail  15 , the blowing-suction tube  2  is driven to make an axial movement relative to the body  1 . The other end of the connecting rod  25  is pivotally connected to a peripheral edge hole  163  at a peripheral edge of the rotary disk  16 . 
     The rotary disk  16  is rotatably mounted on the body  1  by a pivotal shaft B. The rotary disk  16  includes a convex arc-shaped surface (peripheral surface)  161  and a notch  162  that is concave toward a radial inner side from the arc-shaped surface  161 . It should be understood that the notch  162  may extend only in a partial thickness of the rotary disk  16 . The notch  162  may also extend beyond the whole thickness (referring to  FIG. 4A  to  FIG. 4F ) of the rotary disk  16 . 
     The first end of the convex rod  17  is fixed to the rotary disk  16 , and a second end of the convex rod  17  extends outward from a peripheral edge of the rotary disk  16  from the position of the notch  162 . The second end of the convex rod  17  may be connected to a pivotal shaft (or a pivotal shaft and a roller)  171 . 
     The linkage member  73  is fixedly connected to the volute  33  by a pin A 1 . The linkage member  73  includes a concave-arc-shaped first sliding surface  731 , a concave-arc-shaped second sliding surface  732 , and an opening groove  733  located between the two sliding surfaces  731  and  732 . The opening groove  733  may accommodate the pivotal shaft  171  at the second end of the convex rod  17 . An arm portion formed with the opening groove  733  on the linkage member  73  may extend into the notch  162  of the rotary disk  16  without interfering with the rotation of the rotary disk  16 . The first sliding surface  731  and the second sliding surface  732  match the arc-shaped surface  161  of the rotary disk  16 . Referring to  FIG. 4A , when the blowing suction device  100  is in the blowing mode, the arc-shaped surface  161  of the rotary disk  16  faces the first sliding surface  731 . Referring to  FIG. 4D , when the airflow generation apparatus  3  switches to the suction mode, the arc-shaped surface  161  of the rotary disk  16  faces the second sliding surface  732 . 
     Referring to  FIG. 3A  and  FIG. 3B , a bending portion  251  is formed near the second end, connected to the rotary disk  16 , of the connecting rod  25 , so that the pivotal shaft B protruding from the rotary disk  16  does not affect the movement of the connecting rod  25 . After extending from the body  1 , the pivotal shaft B may be connected to the corresponding operation component  5 , so as to drive the rotary disk  16  to rotate. Specifically, the rotary disk  16  is disposed between the airflow generation apparatus  3  and the operation component  5 . The pivotal shaft B is specifically an anti-rotation plug  164  extending toward the operation component  5 . The anti-rotation plug  164  is at least partially disposed as a flat rectangular structure. The anti-rotation plug is inserted with a threaded structure  1641  in a transverse direction. 
     It should be understood that another pin extending from the body  1  may be disposed at an eccentric position that does not interfere with the connecting rod  25  on the rotary disk  16 . In this case, an arc-shaped groove for the another pin to rotate through is formed on the body  1 . In this solution, the pivotal shaft B does not necessarily protrude from the surface, near the connecting rod  25 , of the rotary disk  16 . The connecting rod  25  does not necessarily have the foregoing bending portion  251 . 
     The action process of the linkage apparatus according to this embodiment is described below with reference to  FIG. 3A  to  FIG. 4F  and  FIG. 11  to  FIG. 19 . 
       FIG. 4A  to  FIG. 4F  show a switching process from the blowing mode of the blowing suction device to the suction mode of the blowing suction device. As shown in  FIG. 3B  and  FIG. 4A , in the blowing mode, the first end  21  of the blowing-suction tube  2  is connected to the air outlet portion  332  of the volute  33 . The pivotal shaft  24  mounted on the blowing-suction tube  2  is located at an end, near the volute  33 , of the guide rail  15 . The first sliding surface  731  of the linkage member  73  is in slidable contact with the arc-shaped surface  161  of the rotary disk  16 . The pivotal shaft  171  of the convex rod  17  is separate from the opening groove  733 . 
     The rotary disk  16  is rotated in a clockwise direction from the state. The pivotal shaft  24  (the blowing-suction tube  2 ) makes an axial movement away from the volute  33 . The first sliding surface  731  of the linkage member  73  slides relative to the arc-shaped surface  161  of the rotary disk  16 . The linkage member  73  (the volute  33 ) is still. 
     As shown in  FIG. 4B , after rotation from the state shown in  FIG. 4A  by a particular angle, the pivotal shaft  24  is away from an end, close to the volute  33 , of the guide rail  15  (that is, the pivotal shaft  24  makes a forward axial movement). The blowing-suction tube  2  is detached from the volute  33 . The pivotal shaft  171  of the convex rod  17  starts to be joined to the opening groove  733  of the linkage member  73 . At least before this point, the fitting between the arc-shaped surface  161  of the rotary disk  16  and the first sliding surface  731  of the linkage member  73  is used to position the linkage member  73 . This ensures that the pivotal shaft  171  of the convex rod  17  can be reliably joined to the opening groove  733  of the linkage member  73 . 
     It should be understood that the width of the opening groove  733  may be slightly greater than the diameter of the pivotal shaft  171 , so that the pivotal shaft  171  easily enters into the opening groove  733  and the pivotal shaft  171  is prevented from being stuck in the opening groove  733 . 
     Subsequently, as shown in  FIG. 4C , the rotary disk  16  continues to rotate, the pivotal shaft  24  moves to a limit position at an end, away from the volute  33 , of the guide rail  15 , and the convex rod  17  drives the linkage member  83  to rotate, to enable the volute  33  to rotate. 
     In this embodiment, from the state in  FIG. 4A  to the state in  FIG. 4D , the linkage member  83  (the volute  33 ) rotates by 90 degrees. As shown in  FIG. 4D , the pivotal shaft  171  of the convex rod  17  starts to be detached from the opening groove  733  of the linkage member  73 . The arc-shaped surface  161  of the rotary disk  16  matches the second sliding surface  732  of the linkage member  73 , and the rotary disk  16  inhibits the rotation of the linkage member  73 . In the state shown in  FIG. 4D , the air inlet portion  331  of the volute  33  is aligned with the first end  21  of the blowing-suction tube  2 . 
     As shown in  FIG. 4E , the rotary disk  16  continues to rotate in a clockwise direction, and the pivotal shaft  24  at a first end of the connecting rod  25  drives the blowing-suction tube  2  to approach the volute  33  to enable the first end  21  of the blowing-suction tube  2  to start to be joined to the air inlet portion  331  of the volute  33 . In this case, the linkage member  83  (the volute  33 ) does not rotate. 
     Referring to  FIG. 4F  and  FIG. 3A , the rotary disk  16  rotates in a clockwise direction to a final position, the pivotal shaft  24  moves to a limit position at an end, near the volute  33 , of the guide rail  15 , the blowing-suction tube  2  is joined in a completely sealed manner to the air inlet portion  331  of the volute  33 , and the single-tube blowing suction device  100  is in a suction state. 
     A process in which the blowing suction device  100  switches from the blowing mode to the suction mode is described above. It should be understood that in the order from  FIG. 4F  to  FIG. 4A , it is only necessary to rotate the rotary disk  16  in a counterclockwise direction to switch the blowing suction device  100  from the suction mode to the blowing mode. 
     As described above, the connecting rod  25  and the rotary disk  16  in the linkage apparatus in this embodiment form a crank connecting rod mechanism, so that the rotation of the rotary disk  16  may be converted into the axial movement of the blowing-suction tube  2 . The rotary disk  16 , the convex rod  17 , and the linkage member  73  in the linkage apparatus in this embodiment form a Geneva mechanism, so that the continuous rotation of the rotary disk  16  may be converted into intermittent rotation of the linkage member  73  (the volute  33 ). In this embodiment, the crank connecting rod mechanism and the Geneva mechanism are integrated to provide a linkage apparatus with a simple structure. 
     As described above, the linkage member  73  includes two movement processes. When the linkage member  73  slides relative to the arc-shaped surface  161  of the rotary disk  16 , the position of the linkage member  73  does not change. When the linkage member  73  is joined to the convex rod  17 , the rotation of the linkage member  73  is implemented, and the rotational angle is 90 degrees. Referring to  FIG. 4A  to  FIG. 4F , the rotational angle of the rotary disk  16  is greater than the rotational angle of the linkage member  73  (the volute  33 ), and is less than or equal to 360 degrees. 
     Compared with the first embodiment in which the toggle  9  is pushed to enable the blowing-suction tube  2  to be separate from the volute  33 , the volute  33  is then rotated, and finally the toggle  9  is pushed to enable the blowing-suction tube  2  to be joined to the volute  33 , in this embodiment, it is only necessary to rotate the rotary disk  16  to implement switching between the blowing and suction, so that the human-machine use comfort is further improved. 
     Further, the weight of the motor  31  accounts for a very large part in the weight of the entire airflow generation apparatus  3 . Therefore, there is a risk that when rotating to the suction position, the airflow generation apparatus  3  further accidentally moves to the blowing position along the arrow P 1  because the weight of the motor  31  is relatively heavy. There is also a risk that the airflow generation apparatus  3  rotates because of an accidental touch or another unexpected situation, affecting use of a user. To avoid these risks, in this implementation, the linkage apparatus  7  further includes a locking mechanism  71  capable of limiting the airflow generation apparatus  3  at the blowing position or limiting the airflow generation apparatus at the suction position. 
     As shown in  FIG. 11 , in the transverse direction, the locking mechanism  71  is disposed between the operation component  5  and the main unit housing  10 . 
     As shown in  FIG. 11  to  FIG. 16 , the operation component  5  includes a hand wheel  51  provided with a concave accommodating cavity  50 , a base  52  disposed in the accommodating cavity  50  of the hand wheel  51  and protruding toward the airflow generation apparatus  3 , a press member  53  at least partially accommodated in the hand wheel  51 , and a limit member  54  sleeved over the base  52  and limiting the locking mechanism  71  from disengagement. The base  52  is a pillar structure, and the base  52  and the hand wheel  51  are integrally disposed. The base  52  is provided with an anti-rotation socket  521  extending in the transverse direction. The anti-rotation socket  521  is a flat rectangular slot adapting to the anti-rotation plug  164  with a flat rectangular structure. In this embodiment, the anti-rotation plug  164  on the rotary disk  16  is accommodated in the flat rectangular slot, to prevent relative rotation between the hand wheel  51  and the rotary disk  16  when the hand wheel  81  drives the rotary disk  16  to rotate. Further, an outer surface of the hand wheel  51  is further provided with a through hole  510  in communication with the flat rectangular slot. The through hole  510  is used for a screw  55  to pass through for threaded fastening with the threaded structure  1641  on the anti-rotation plug  164 . 
     Specifically, referring to  FIG. 11  and  FIG. 13  to  FIG. 15 , the locking mechanism  71  includes a locking member  711  and an elastic member  712 . The locking member  711  is at least partially located in the accommodating cavity  50  of the operation component  5  and includes a base portion  713 , a fitting portion  714  disposed on the base portion  713 , and a locking pin  715  located at a free end of the base portion  713 . The main unit housing  10  is provided with a slot  101  that is capable of being locked to and fitting the locking pin  715  of the locking mechanism  71  to lock the blowing suction device  100  in a corresponding working mode. Specifically, the slot  101  includes a first slot  1011  that is capable of being locked to and fitting the locking pin  715  to lock the blowing suction device  100  in the blowing mode and a second slot  1012  that locks the blowing suction device  100  in the suction mode (as shown in  FIG. 11 ). In this embodiment, the first slot  1011  and the second slot  1012  are disposed opposite. 
     As shown in  FIG. 11 ,  FIG. 12 , and  FIG. 14  to  FIG. 16 , in this embodiment, the press member  53  includes a first button  531  and a second button  532  that are pivotally connected to the base  52  and are disposed symmetrically. The first button  531  and the second button  532  are at least partially accommodated in the accommodating cavity  50 . Each of the first button  531  and the second button  532  includes an exposed pressing portion  533  to be pressed by an operator, an action portion  534  extending into the accommodating cavity  50  of the operation component  5 , and a slide portion  535  that is limited by and fits the limit member  54 . The action portion  534  is in contact with the fitting portion  714 , so that when the first button  531  and the second button  532  are pressed, the action portion  534  can displace relative to the main unit housing  10  and at the same time push the fitting portion  714  of the locking mechanism  71 , so that the locking pin  715  moves away from the first slot  1011  or the second slot  1012 , to implement that the operation component  5  can use the rotary disk  16  to drive the airflow generation apparatus  3  to rotate. Specifically, when the blowing suction device  100  needs to switch from the suction mode to the blowing mode, the operation component  5  may move relative to the main unit housing  10  by the preset distance under the effect of an external force, to drive the locking mechanism  71  to compress the elastic member  712  and to be separated from the first slot  1011  of the main unit housing  10 . Next, the operation component  5  drives the airflow generation apparatus  3  to rotate from the blowing position to the suction position. Finally, the operation component  5  is released, and the elastic member  712  drives the locking pin  715  to be locked in the second slot  1012 . The elastic member  712  is held between the locking mechanism  71  and the operation component  5 . More specifically, the elastic member  712  is held between the locking mechanism  71  and the limit member  54 , to provide the locking mechanism  71  with a restoring force for driving locking between the locking pin  715  and the second slot  1012 . Similarly, when the blowing suction device  100  needs to switch from the blowing mode to the suction mode, the operation component  5  may move relative to the main unit housing  10  by the preset distance under the effect of an external force, to drive the locking mechanism  71  to compress the elastic member  712  and to be separated from the second slot  1012  of the main unit housing  10 . Next, the operation component  5  drives the airflow generation apparatus  3  to rotate from the suction position to the blowing position. Finally, the operation component  5  is released, and the elastic member  712  drives the locking pin  715  to be locked in the first slot  1011 . 
     More specifically, a side, facing the action portion  534 , of the fitting portion  714  is formed with a fitting surface  7140 , and the fitting surface  7140  is an inclined slope. When the blowing suction device  100  is in the suction mode, in the process of pressing the first button and the second button, the action portion  534  moves downward along the inclined fitting surface  7140 , and drives the fitting portion  714  to move toward the base  52  to be disengaged from the second slot  1012 . The elastic member  712  is in a compressed state. In this case, if the operation component  5  is rotated to the blowing position, the first button  531  and the second button  532  are released, and the elastic member  712  is in a released state. The released elastic member  712  drives the locking pin  715  and the first slot  1011  to be engaged. 
     It may be understood that in this embodiment, the press member  53  is provided with two buttons. Certainly, in some other embodiments, the press member  53  may be provided with one button. To prevent the buttons from being excessively released when the locking mechanism  71  is locked to the first slot  1011  or the second slot  1012 , in this implementation, the limit member  54  is further provided with two limit teeth  541  in an extending direction of the through hole. The slide portion  535  of the button  5  is limited between the two limit teeth  541 , so as to move between the two limit teeth  541  by the preset distance. In addition, the limit member  54  further includes two hooks  542  disposed opposite. The two hooks  542  fit the base portion  713  of the locking mechanism  71  to prevent the locking mechanism  71  from being disengaged from the hand wheel  51  in the transverse direction. 
     The action process of the garbage bag  7  during switching between blowing and suction is described below. 
     In an example, in the suction mode, the air outlet portion  332  of the volute  33  is connected in a sealed manner to the connection port  73  of the garbage bag  7 . In an optional solution, a garbage bag  3  is movably mounted on the body  1 . During switching from the suction mode to the blowing mode, the garbage bag  3  may first be moved away from the rotational axis A. Next, the airflow generation apparatus (the volute  33 ) rotates to the blowing mode. During switching from the blowing mode to the suction mode, first, the airflow generation apparatus (the volute  33 ) is rotated to the suction mode. Next, the garbage bag  3  moves toward the rotational axis A, so that the connection port  32  of the garbage bag  3  is connected in a sealed manner to the air outlet portion  332  of the volute  33 . Certainly, the present invention is not limited thereto. 
     A connection manner between the air inlet portion  331  and the air outlet portion  332  of the volute  33  and the blowing-suction tube  2  is further described below. 
     In the suction mode, the air inlet portion  331  of the volute  33  is sleeved over the first end  21  of the blowing-suction tube  2  to implement sealing. In the blowing mode, a fastening portion on an outer side of the air outlet portion  332  of the volute  33  is clamped to the first end  21  of the blowing-suction tube  2 , to inhibit the shaking of the blowing-suction tube  2 . 
     Referring to  FIG. 1A  to  FIG. 2B , in this embodiment, a cross-sectional area of an airflow channel of the air inlet portion  331  of the volute  33  in a direction perpendicular to an air inlet direction of the air inlet channel is greater than a cross-sectional area of an airflow channel of the air outlet portion  332  in a direction perpendicular to the air outlet direction thereof. For example, when the air inlet portion  331  and the air outlet portion  332  are both approximately tubular, the inner diameter of the air inlet portion  331  is greater than that of an outlet portion  82 . Because the air inlet opening  3310  (the inner diameter) of the air inlet portion  331  is relatively large, in the suction mode, a relatively large air intake may be implemented, and debris such as leaves can easily enter the volute  33  through the blowing-suction tube  2  and the air inlet portion  331  and is crushed by the fan  32  into pieces to enter the garbage bag  3 . The air outlet opening  3320  (the inner diameter) of the air outlet portion  332  is relatively small, in the blowing mode, a relatively fast air discharge speed can be implemented in the blowing-suction tube  2 , thereby obtaining a relatively large blowing force. 
     Referring to  FIG. 2A , the inner diameter of the air inlet portion  331  matches the outer diameter of the first end  21  of the blowing-suction tube  2 , so that in the suction mode, the air inlet portion  331  is sleeved over the first end  21  of the blowing-suction tube  2 . The present invention is not limited to that the inner diameter of the air inlet portion  331  matches the outer diameter of the first end  21  of the blowing-suction tube  2 . The outer diameter of the air inlet portion  331  may further match the inner diameter of the first end  21  of the blowing-suction tube  2 . 
     Referring to  FIG. 2B , the air outlet portion  332  includes an inner tube  3321  and an external fastening portion  3322  that are disposed generally approximately. The inner tube  3321  and the external fastening portion  3322  are connected to each other at base ends thereof, that is, at a connecting portion  3324 , so that a clamping groove  3323  generally extending in a circumferential direction and an axial direction of the blowing-suction tube  2  is defined between the inner tube  3321  and the external fastening portion  3322 . The outer diameter of the inner tube  3321  is less than the inner diameter of the first end  21  of the blowing-suction tube  2 . In the blowing mode, the inner tube  3321  is accommodated in the first end  21  of the blowing-suction tube  2 . The external fastening portion  3322  may be disposed as a plurality of parts at intervals in the circumferential direction of the blowing-suction tube  2 . The inner circumferential shape of the external fastening portion  3322  matches the external circumferential shape of the first end  21  of the blowing-suction tube  2 , so that in the blowing mode, the external fastening portion  3322  is externally connected to the first end  21  of the blowing-suction tube  2 . The present invention may be, but is not limited to that the connecting portion  3324  defines the position of the first end  21  of the blowing-suction tube  2 . 
     The present invention is not limited to that the inner diameter of the external fastening portion  3322  matches the outer diameter of the first end  21  of the blowing-suction tube  2 . The external fastening portion  3322  may further match the inner diameter of the first end  21  of the blowing-suction tube  2 . In this case, a step may further be formed at the external fastening portion  3322 . The step may be held against the first end  21  of the blowing-suction tube  2 , to implement axial positioning of the blowing-suction tube  2  in the blowing mode. Certainly, an axial positioning manner of the blowing-suction tube  2  is not limited thereto. 
     The connecting portion  3324  preferably does not extend in the entire circumference of the blowing-suction tube  2 . This ensures that an annular space between the first end  21  of the blowing-suction tube  2  and the inner tube  3321  is in fluid communication with the inside of the body  1  and the outside of the volute  33 . 
     Further, a cross-sectional area of the inner tube  3321  in a direction perpendicular to the air outlet direction is less than a cross-sectional area of the first end  21  of the blowing-suction tube  2  in the direction perpendicular to the air outlet direction. In this embodiment, the inner tube  3321  extends into the first end  21  of the blowing-suction tube  2 . A section in communication with external air is provided between the inner tube  3321  and the first end  21 . In the blowing mode, because of Bernoulli&#39;s principle, external air is sucked into the blowing-suction tube  2  through this section under the effect of an airflow of the inner tube  3321 , thereby increasing an air volume of the blowing suction device  100  in the blowing mode. 
     It should be understood that in the blowing mode, the inner tube  3321  does not necessarily extend into the first end  21  of the blowing-suction tube  2 . The inner tube  3321  may further be separate from the first end  21  of the blowing-suction tube  2  by a distance in the extending direction of the blowing-suction tube  2 . Alternatively, the port of the inner tube  3321  and the port of the first end  21  may be flush with each other, that is, generally in the same plane. 
     In the foregoing description, for simplicity, a horizontal placement state of the blowing-suction tube  2  is used to describe the relationship between parts. However, it should be understood that during use, the blowing-suction tube  2  is usually inclined relative to the horizontal direction. 
     Second Embodiment 
     The second implementation of the present invention is described below with reference to  FIG. 5 . 
     In the first embodiment, the body air inlet portion  13  is located below the holding portion  11 . However, the present invention is not limited thereto. 
     For example, in this embodiment, the body air inlet portion  13  includes an air inlet channel  132  located below the grip portion  11 , an opening  130  located at one end of the air inlet channel  132 , and an exit  133  located at the other end of the air inlet channel  132 . The opening  130  is located on a front side of the grip portion  11 . That is, the opening direction of the opening  130  is basically consistent with the extending direction of the blowing-suction tube. In the blowing mode, incoming air generally flows along an arrow  13 A to enter the volute  33  through the body air inlet portion  13 . 
     In this embodiment, the opening  130  of the body air inlet portion  13  faces a front-side opening of the body  1 . Compared with that the opening of the body air inlet portion  13  is located below the grip portion  11 , the opening  130  is less likely blocked by a hand holding the grip portion  11 . In addition, the opening  131  or an airflow at the opening  131  is far away from the ears of a user. Therefore, noise perceived by the user can be reduced. 
     Certainly, the opening  130  of the body air inlet portion  13  may be located at any position other than that facing the grip portion  11 , and there may be a plurality of air inlet openings. 
     Third Embodiment 
     The third embodiment of the present invention is described below with reference to  FIG. 6A  to  FIG. 6C . 
     Referring to  FIG. 1A , in the suction mode, the output shaft of the motor  31  is parallel to the central axis of the blowing-suction tube  2 , and the motor  31  and the rotational axis A are located at approximately at the same height. Referring to  FIG. 1B , in the blowing mode, the output shaft of the motor  31  is perpendicular to the central axis of the blowing-suction tube  2 , and the motor body  311  is located below the rotational axis A. 
     Generally, the weight of the motor  31  accounts for a very large part in the weight of the entire airflow generation apparatus  3 . During switching from the suction mode shown in  FIG. 1A  to the blowing mode shown in  FIG. 1B , the center of gravity of the motor  31  lowers, so that the switching is facilitated. During switching from the blowing mode shown in  FIG. 1B  to the blowing mode shown in  FIG. 1A , the center of gravity of the motor  31  rises, and it takes a relatively large force to enable the airflow generation apparatus  3  to rotate to the blowing mode shown in  FIG. 1A . This embodiment is provided to resolve the problem that it takes a relatively large torque to switch from the blowing mode to the suction mode. 
     Referring to  FIG. 6A  to  FIG. 6C , the airflow generation apparatus  3  includes a rotational axis A 2  corresponding to the rotational axis A. The rotational axis A 2  is fixedly connected to the volute  33 . The airflow generation apparatus  3  further includes a switching assisting apparatus  8 . The switching assisting apparatus includes a torsion spring  84 , a torsion spring limit portion  18 , and an abutting portion  85 . As described below in detail, the switching assisting apparatus resists the torque around the rotational axis A 2  applied by the weight of the motor  31  or the entire airflow generation apparatus  3 . The stored energy may rotate in a direction opposite a rotational direction around the rotational axis A 2  applied by the weight of the airflow generation apparatus  3 . 
     Referring to  FIG. 6A , a convex pillar A 21  for mounting the torsion spring  84  is disposed at a position coaxial with the rotational axis A 2  on an outer wall of the volute  33 . A coil  843  of the torsion spring  84  is mounted around the pillar A 21 . A first arm  841  and a second arm  842  of the torsion spring  84  extend from the coil  843 . The abutting portion  85  formed around the convex pillar A 21  is disposed on the outer wall of the volute  33 . The abutting portion  85  has the form of a generally C-shaped rib and includes a first end  851  and a second end  852 . At least the coil  843  of the torsion spring  84  is disposed between the abutting portion  85  and the convex pillar A 21 . The torsion spring limit portion  18  is disposed around the abutting portion  85  on the housing of the body  1 . The torsion spring limit portion  18  also has an approximately C shape. In the example shown in the figure, an angle by which the torsion spring limit portion  18  extends (covered by the C-shaped structure) is greater than an angle by which the abutting portion  85  extends. The torsion spring limit portion  18  has a first end  181  and a second end  182 . Preferably, the abutting portion  85  and the torsion spring limit portion  18  are coaxially disposed with the rotational axis A 2 . 
       FIG. 6A  shows that the blowing suction device is in the suction mode.  FIG. 6C  shows that the blowing suction device is in the blowing mode.  FIG. 6B  shows an intermediate state between the blowing mode and the suction mode. For example, during switching from the suction mode to the blowing mode, as the volute  33  rotates by 90 degrees, the state shown in  FIG. 6B  may be a state of rotating from the blowing mode or the suction mode by approximately 45 degrees. 
     In the blowing mode shown in  FIG. 6A , the first end  181  and the second end  182  of the torsion spring limit portion  18  respectively limit the positions of the first arm  841  and the second arm  842  of the torsion spring  84 . The torsion spring  84  is in a free state or a slightly compressed (that is, the first arm  841  and the second arm  842  approach each other from the free state of the torsion spring  84 ) state. The first end  851  of the abutting portion  85  abuts the first arm  841  of the torsion spring  84 . The second end  852  of the abutting portion  85  is separate from the second arm  842  of the torsion spring  84 . 
     During switching from the suction mode shown in  FIG. 6A  to the blowing mode shown in  FIG. 6C , the volute  33  (the abutting portion  85 ) needs to rotate in the clockwise direction in  FIG. 6A  by 90 degrees. As shown in  FIG. 6B , when the volute  33  (the abutting portion  85 ) rotates by about 45 degrees, the first end  851  of the abutting portion  85  is already separate from the first arm  841  of the torsion spring  84 , and the second end  852  of the abutting portion  85  starts to abut the second arm  842  of the torsion spring  84 . During further switching from the intermediate state shown in  FIG. 6B  to the blowing mode shown in  FIG. 6C , the volute  33  (the abutting portion  85 ) further rotates in the clockwise direction, the abutting portion  85  compresses the torsion spring  84 , so as to store energy in the torsion spring  84 . In this case, the first end  181  of the torsion spring limit portion  18  and the second end  852  of the abutting portion  85  limit a compressed state of a torsion ring  84 . 
     Because the center of gravity of the motor  31  lowers during switching from the suction mode (referring to  FIG. 1A ) to the blowing mode (referring to  FIG. 1B ), the center of gravity of the motor  31  may be used to compress the torsion ring  84 . In this way, during switching from the suction mode to the blowing mode, the volute  33  is prevented from suddenly rotating fast under the effect of the weight of the motor  31 , so that the switching is smoother. It should be understood that the direction of the torque (or rotation) around the rotational axis A 2  applied by the weight of the motor  31  or the entire airflow generation apparatus is consistent with the direction of rotation that compresses the torsion ring  84  or stores energy in the torsion ring  84 . 
     During switching from a blowing state shown in  FIG. 6C  to the suction state shown in  FIG. 6A , the volute  33  (the abutting portion  85 ) rotates in a counterclockwise direction in  FIG. 6C . In this case, a compressed torsion spring  85  releases energy stored in the torsion spring to push the abutting portion  85  (the volute  33 ) to rotate from the blowing state to the suction state. In other words, the potential energy of the torsion spring  85  cancels out a part of the weight of the motor  31 , so as to reduce a force that needs to be applied by a user to raise the motor  31  (the airflow generation apparatus), so that switching from the blowing state to the suction state is smoother. 
     It should be understood that the theme of this embodiment is to use the potential energy stored in the torsion ring  84  to assist in the rotation of the airflow generation apparatus, so that switching between blowing and suction is smoother. With the teachings of the present invention, a person skilled in the art may conceive of other implementations. For example, the convex pillar A 21  may be disposed or formed at the rotational axis A 2  or the housing of the body  8  instead of the volute. For example, the potential energy generated from the stretching or compression of a spiral spring mounted between the housing of the body  1  and the airflow generation apparatus is used to assist in the rotation of the airflow generation apparatus. Therefore, the elastic member used as an energy accumulation portion may be, for example, a torsion spring or a spiral spring. 
     It should be understood that the torsion spring limit portion  18  is not necessarily a C-shaped structure, provided that it has a first limit portion  181  and a second limit portion  182  for limiting the first arm  841  and the second arm  842  of the torsion ring  84 . 
     The first arm  841  of the torsion ring  84  is limited by the first limit portion  181 . Therefore, the abutting portion  85  is not necessarily a C-shaped structure, provided that it can abut a first abutting portion  852  of the second arm  842  of the torsion ring  84  with the rotation of the volute  33 . For example, during switching from the suction mode shown in  FIG. 6A  to the blowing mode shown in  FIG. 6C , the abutting portion  85  abuts the second arm  842  of the torsion ring  84  as soon as the volute  33  rotates. In this case, the first abutting portion ( 852 ) of the abutting portion  85  may be used to limit the second arm  842  of the torsion ring  84  in the suction mode. Therefore, the second limit portion  182  of the torsion spring limit portion  18  may be omitted. 
     In the foregoing embodiment, the torsion spring is mainly used to assist in the rotation of the airflow generation apparatus, so that switching between blowing and suction is smoother. Certainly, a switching assisting apparatus  8  may be alternatively an extension spring  80 . Specifically, as shown in  FIG. 17  and  FIG. 18 , the extension spring  80  includes a first retaining portion  801  connected to the body  1 , a second retaining portion (not shown) connected to the airflow generation apparatus  3 , and an elastic portion  803  connected between the first retaining portion  801  and the second retaining portion  802 . The elastic portion  803  is disposed to be a spiral spring. When the blowing suction device is in the blowing mode, the elastic portion  803  is in a stretched state, and when the blowing suction device  100  switches from the blowing mode to the suction mode, the elastic portion  803  uses a restoring force thereof and coordinates with the blowing-suction switching mechanism to drive the airflow generation apparatus  3  to rotate. 
     Fourth Embodiment 
     The fourth embodiment of the present invention is described below with reference to  FIG. 7 . 
     This embodiment focuses on the related size of the volute  33  to miniaturize the volute  33 . 
       FIG. 7  is a sectional view of the volute  33  taken along the rotational axis A (referring to  FIG. 1A  and  FIG. 1B ) of the volute  33  and the air outlet direction of the air outlet portion  332  (an inner tube  821 ) and also shows the first end  21  of the blowing-suction tube  2 . 
     The volute  33  is one of core parts of a fan, and especially a centrifugal fan. The volute  33  is used for gathering gas from the centrifugal fan, guiding the gas to the air outlet opening  3320 , that is, the air outlet portion  332 , of the volute  33 , and converting a part of dynamic pressure of the gas into static pressure. The volute  33  includes a spiral portion  334 , a throat portion  335 , and a volute tongue  336  formed between a starting end of the spiral portion  334  and the throat portion  335 . The volute tongue  336  is near the air outlet opening  3320  of the volute  33  of the fan. The volute tongue is used for splitting an airflow guided to the air outlet opening  3320  of the volute  33 , to prevent a part of gas from circulating in the volute  33 . The volute tongue  336  cuts a high-speed airflow discharged from the fan  32 , generating much noise. A distance between the volute tongue  336  and an edge  327  of the fan is increased to effectively reduce noise. 
     In this embodiment, the distance that is marked by the numeral  336 A and is from the volute tongue  336  to the edge  327  of a vane (a blade) is greater than or equal to 0.05 times of the diameter of the fan. In one of the embodiments, the distance between the volute tongue  336  and the edge  327  of the fan (the blade) is 0.08 times to 0.12 times of the diameter of the fan. Preferably, the distance  336 A from the volute tongue  336  to the edge  327  of the fan is greater than or equal to 8 mm. More preferably, the distance  336 A from the volute tongue  336  to the edge  327  of the fan is 9 mm to 15 mm. It should be noted that the numeral  336 A herein may be understood as the smallest distance between the volute tongue  336  and the edge  327  of the vane. 
     The radial size of the volute  33  affects the distance between the machine and the legs of a person when a user holds the blowing suction device. By reducing the radial size of the volute  33 , an unfolding angle of arms can be reduced, thereby improving human-machine interaction friendliness and facilitating the rotation of the air generation portion to implement switching between blowing and suction. As shown in  FIG. 7 , in the direction perpendicular to the air outlet direction of the air outlet portion  332 , the largest distance between a rotational center O of the fan  32  of the volute  33  and an inner wall of the volute  33  is L 1 , and the distance between the rotational center O of the fan to the edge of the blade is L 2 . A ratio of the distance L 1  to the distance L 2  is greater than or equal to 1.2 and is less than or equal to 2. Therefore, the ratio may be 1.3, 1.4, 1.5, 1.6, 1.7, 1.8 or 1.9. Preferably, the ratio of the distance L 1  to the distance L 2  is greater than or equal to 1.8 and is less than or equal to 2. In this embodiment, in one aspect, the distance between the edge of the fan  32  and the inner wall of the volute  22  is reduced, to reduce the radial size of the volute  33 . In another aspect, the distance between the volute tongue  86  and the edge of the fan is increased to reduce severe noise caused by the distance between the inner wall of the volute and the edge of the fan. Specifically, the largest distance L 1  between the rotational center of the fan of the volute  33  and the inner wall of the volute  33  is less than or equal to 117 mm. In addition, a ratio of the distance  336 A to the distance L 1  is greater than or equal to 8/117=0.06. The ratio is, for example, 0.07, 0.09 or 0.12. 
     To reduce the radial size of the volute  33  and at the same time ensure the blowing and suction efficiency, in this embodiment, the thickness of the volute  33  is increased to balance the volume of the volute  33 , thereby ensuring that a sufficient volume of air enters the volute  33 . Specifically, as shown in  FIG. 10 , in an extending direction of the rotational axis of the fan  32 , the largest distance between two opposite inner walls of the volute  33  is W 1 , the height of the fan is W 2 , and a ratio of the largest distance W 1  to the height W 2  is greater than 1. Preferably, the range of the ratio is greater than 1 and less than or equal to 1.3. Therefore, the ratio may be 1.1, 1.17, 1.18, 1.19, 1.21, 1.25, 1.26, 1.27, 1.28 or 1.29. 
     In this embodiment, the cross-sectional area of the air outlet opening  3320  of the volute  33  is reduced to increase the air speed. An auxiliary air outlet area (gap)  30  in communication with the outside is formed between the air outlet opening  3320  of the volute and the first end  21  of the blowing-suction tube  2  to increase an air outlet volume in the blowing mode. Specifically, as shown in  FIG. 7  and  FIG. 9 , in the blowing mode, there is a gap between the air outlet opening  3320  and the first end  21  of the blowing-suction tube  2 , so that an external airflow can enter the blowing-suction tube  2  through the gap  30 . In addition, the air outlet opening  3320  and the first end  21  at least partially overlap in the axial direction or a front end surface of the air outlet opening  3320  is flush with a rear end surface of the first end  21 . 
     The cross-sectional area of the air outlet opening  3320  of the volute  33  in the direction perpendicular to the air outlet direction needs to fall in an appropriate range. The cross-sectional area of the blowing-suction tube  2  in the air outlet direction needs to be combined and the blowing and suction efficiency needs to be considered. When the cross-sectional area of the air outlet opening is excessively small, leaves may clog in the suction mode, and when the cross-sectional area is excessively large, a negative pressure generated in the blowing mode is relatively small, and the effect of driving surrounding air to flow into the blowing-suction tube  2  to increase an air volume is not obvious. In this embodiment, the range of a ratio of the cross-sectional area of the first end of the blowing-suction tube  2  to that of the air outlet opening  3320  of the volute is 1.5 to 6. Preferably, the range of the ratio of the cross-sectional area of the first end of the blowing-suction tube  2  to that of the air outlet opening  3320  of the volute is 3 to 5. Specifically, the range of the ratio may be 4, 4.2, 4.5, 4.6 or 4.8. In an example, as shown in  FIG. 7 , the diameter  332 D of the air outlet opening  3320  of the volute  33  is 50 mm to 80 mm, and the diameter  21 D of the first end  21  of the blowing-suction tube  2  is 100 mm to 130 mm. It should be noted that the first end herein may be understood as a circular opening, near the airflow generation apparatus, of the blowing-suction tube  2 . 
     Fifth Embodiment 
     The fifth embodiment of the present invention is described below with reference to  FIG. 8A  and  FIG. 8B . 
     Different from the first embodiment, in this embodiment, the airflow generation apparatus (the volute  33  and the motor  31 ) does not rotate relative to the body  1  (the holding portion  11 ). Instead, alternatively, the blowing-suction tube  2  may rotate relative to the body  1  and the airflow generation apparatus, to implement switching between blowing and suction. 
     Referring to  FIG. 8A  and  FIG. 8B , in this embodiment, in the airflow generation apparatus, more specifically, the motor  31  and the volute  33  are fixedly connected to the body  1 . The volute  33  includes an air inlet portion  331  and an air outlet portion  332 . 
     The blowing suction device further includes a support  89  used for rotatably connecting the blowing-suction tube  2  to the volute  33 . The support  89  includes a blowing-suction tube connecting portion  891  and a volute connecting portion  893 , which may be integrally formed. The first end  21  of the blowing-suction tube  2  is connected to the blowing-suction tube connecting portion  891  and may make an axial movement relative to the blowing-suction tube connecting portion  891  along the central axis of the blowing-suction tube  2 . The volute connecting portion  893  is rotatably connected to the volute  33  at the numeral  894 . That is, the blowing-suction tube  2  can be pivotally disposed around the rotational axis A′ with respect to the grip portion, and the blowing-suction tube  2  is rotatable between the blowing position and the suction position. At the blowing position (as shown in  FIG. 8A ), the rotational axis of the fan  32  is perpendicular to the extending direction of the blowing-suction tube  2 . At the suction position (as shown in  FIG. 8B ), the rotational axis of the fan  32  is basically consistent with the extending direction of the blowing-suction tube  2 . 
     In addition to that the blowing-suction tube  2  rather than the airflow generation apparatus rotates, in this embodiment, connection manners between the blowing-suction tube  2  and the air inlet portion  331  and the air outlet portion  332 , a manner of the axial movement of the blowing-suction tube  2  relative to the support  89 , and a manner of switching between blowing and suction are similar to that in the first and second in this embodiments. 
     The action process during switching between blowing and suction is described below. 
     In this embodiment, the blowing-suction tube  2  is slidably connected to the blowing-suction tube connecting portion  891 . As shown in  FIG. 8A  and  FIG. 8B , a toggle  9 A includes a first portion  9 A 1  and a second portion  9 A 2 . The toggle  9 A is pivotally mounted at the blowing-suction tube connecting portion  891  by a pivotal shaft  14 A at an intersection between the first portion  9 A 1  and the second portion  9 A 2 . An end of the second portion  9 A 2  is formed with a long hole  91 A. A pivotal shaft  23 A extending from the sidewall of the blowing-suction tube  2  is inserted in the axial long hole  892  in the support  89  and the long hole  91 A in the toggle  9 A. In this way, a first part  9 A 1  of the toggle  9 A may be pushed to enable the toggle  9 A to rotate around the pivotal shaft  14 A, so as to drive the first end  21  of the blowing-suction tube  2  to move toward or away from the airflow generation apparatus (volute  33 ). 
     For example, during switching from the suction mode in  FIG. 8A  to the blowing mode in  FIG. 8B , first, the first part  9 A 1  of the toggle  9 A is pulled toward the holding portion  11  to enable the first end  21  of the blowing-suction tube  2  to move away from the volute  33  to be detached from the air inlet portion  331  of the volute  33 . Next, the support  89  and the blowing-suction tube  2  are rotated together relative to the body  1  in the counterclockwise direction in  FIG. 8A  by 90 degrees, to enable the air outlet portion  332  of the volute  33  to be aligned with the first end  21  of the blowing-suction tube  2 . Finally, the first part  9 A 1  of the toggle  9 A is pushed to enable the first end  21  of the blowing-suction tube  2  to move toward the volute  33  to be joined to the air outlet portion  332  of the volute  33 . 
     During switching from the blowing mode shown in  FIG. 8B  to the suction mode shown in  FIG. 8A , the toggle  9 A is pushed and the support  89  and the blowing-suction tube  2  are enabled to rotate in the direction of an arrow P 3 . In the blowing mode shown in  FIG. 8A , the air outlet portion  332  is connected to the garbage bag. In the blowing mode shown in  FIG. 8B , the air inlet portion  331  is exposed. 
     The foregoing embodiments may be appropriately combined with each other. For example, the second embodiment may be combined with the second embodiment. The third embodiment may be combined with the first embodiment. The fourth embodiment may be combined with the first to third embodiments. 
     Certainly, the present invention is not limited to the foregoing embodiments. A person skilled in the art may make various changes and variations to the foregoing embodiments of the present invention with the teachings of the present invention without departing from the scope of the present invention. 
     (1) For example, the collection apparatus is not limited to the garbage bag  7 . A part of the body  1  may be used as the collection apparatus. 
     The garbage bag  3  may be partially or nearly completely exposed from the body  1 . 
     (2) People sometimes collectively refer a motor, a vane (a blade), and a housing including a volute as a fan. In this application, the fan does not include the foregoing motor and volute, includes vanes, and may further include a shaft connected to the fan. 
     (3) In the present invention, the blowing-suction tube  2  is not necessarily a straight tube. 
     In addition, the blowing-suction tube  2  does not necessarily have the same diameter at different positions in the axial direction thereof. 
     (4) In the blowing mode, the body air inlet portion  13  is not necessarily in direct communication with the air inlet portion  331  of the volute  33 , and a gap may be kept therebetween. 
     (5) The guide rail (or the guide groove)  15  may be omitted. The inner circumferential surface of the blowing-suction tube connecting portion  12  may be used for guiding the blowing-suction tube  2 .