JP2010084393A - Air duct of blower and the blower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air duct of a blower which can reduce a burden imposed on a user by the weight of the air duct and can suppress the moment generatd on an operator's hand, and the blower. <P>SOLUTION: In the air duct of the blower, a buoyancy forming portion 54 can impart buoyancy F3 to the air duct 4 by utilizing pumped air pumped to the air duct 4. Thus, the air duct 4 can be made light in weight by the amoun of the buoyancy, and the burden imposed on the user by the weight of the air duct 4 can be reduced. Furtheremore, the moment of a grip by a reaction generated by the ejection of the pumped air can also be suppressed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a blower wind pipe and a blower.

  2. Description of the Related Art Conventionally, a blower body that generates pressurized air and is carried on the user's back and a wind pipe connected to the blower body are used to clean fallen leaves and the like by ejecting the pressurized air that is pumped from the blower body from the wind pipe. A shoulder type blower is known (for example, Patent Document 1). In such a blower, an operation grip is attached to the wind pipe. At the time of work, the user directs the wind tube in a desired direction while supporting the wind tube via the operation grip, thereby ejecting the compressed air in the desired direction to clean the fallen leaves and the like.

JP 2007-71029 A

  However, in such a blower, since the user needs to support the wind pipe during work, when the work is performed for a long time, the grip portion is arranged at a position offset with respect to the axis of the flow of the compressed air. Therefore, a moment is generated in the operator's hand due to the reaction force caused by the discharge of compressed air. In addition, there is a problem that the operator is burdened by the weight of the wind pipe.

  An object of the present invention is to provide a blower wind pipe and a blower capable of reducing the burden on the user due to the weight of the wind pipe and at the same time suppressing the moment generated in the hand of the operator.

  A blower wind tube according to a first aspect of the present invention is a blower wind tube, and includes a buoyancy forming unit that imparts buoyancy to the wind tube by using compressed air fed to the wind tube. It is characterized by that.

  The blower windpipe according to claim 2 of the present invention is the blower windpipe according to claim 1, wherein the outlet end of the windpipe is reduced in diameter toward the downstream side and the open end is on the lower side. And an atypical cylindrical portion that is formed on the downstream side when the outlet end portion is cut by a plane perpendicular to the center line of the wind tube so as to include the lowest point of the opening end, The atypical cylindrical portion is the buoyancy forming portion, and the upward force received by the upper surface of the inner surface by the compressed air is larger than the downward force received by the lower surface of the inner surface by the compressed air, whereby the wind tube It is characterized by giving buoyancy to.

  The blower wind tube according to claim 3 of the present invention is the blower wind tube according to claim 2, wherein an operation grip is provided for a user to hold and support the wind tube, and the open end is The reaction force generated when the compressed air is ejected downward from the opening end is inclined at an angle toward the operation grip.

  The blower windpipe according to claim 4 of the present invention is the blower windpipe according to claim 1, wherein an outlet end of the windpipe is provided with a flare portion that expands toward the downstream side. The flare portion is the buoyancy forming portion, and the upper side is spread outward from the center line of the wind tube than the lower side, and a larger eddy current is generated on the upper side than the lower side when jetted air is ejected. The buoyancy is given to the wind tube.

  The blower windpipe according to claim 5 of the present invention is the blower windpipe according to any one of claims 1 to 4, wherein the windpipe includes a reduced diameter portion that is reduced in diameter as it proceeds downstream. The reduced diameter portion is the buoyancy forming portion, and is inclined so that the downstream end is tilted downward, and the upward force received by the upper surface of the inner surface by the pressurized air is lower at the inner surface of the compressed air. The buoyancy is imparted to the wind pipe by being larger than the downward force received by the air pipe.

  A blower according to a sixth aspect of the present invention includes: a blower body that generates and feeds compressed air; and a wind pipe that is connected to the blower body and ejects the compressed air that is pumped from the blower body. The wind pipe is a blower wind pipe according to any one of claims 1 to 5.

  According to the invention of claim 1, since the buoyancy can be imparted to the wind pipe using the pumped air that is pumped to the wind pipe by the buoyancy forming portion, the wind pipe can be lightened accordingly, The burden on the user due to the weight of the wind pipe can be reduced.

According to the invention of claim 2, the outlet end portion is reduced in diameter as it goes downstream. In addition, since the opening end is inclined downward, when the exit end is cut by a plane perpendicular to the center line of the wind pipe so as to include the lowest point of the opening end, An irregular shaped cylindrical portion is formed on the downstream side. In this modified cylindrical part, the area of the upper part of the inner surface is larger than that of the lower part of the inner surface. Therefore, in the modified cylindrical portion, the upward force received by the upper surface of the inner surface by the pressurized air is greater than the downward force received by the lower surface of the inner surface, so that buoyancy is exerted and buoyancy can be imparted to the wind tube. .
Moreover, since the structure of an exit edge part is simple, formation is easy.
In addition, since the outlet end portion is reduced in diameter as it goes downstream, the wind speed can be increased.

  According to the invention of claim 3, the opening end of the outlet end portion is inclined at an angle at which the reaction force due to the ejection of the pressurized air is directed toward the operation grip. The occurrence of M can be suppressed. Therefore, the burden on the user who holds the operation grip can be reduced.

According to the invention of claim 4, the upper side of the flare portion provided at the outlet end portion of the wind tube extends outward from the center line of the wind tube rather than the lower side. The air flowing in this direction is ejected from the center line of the wind tube toward the outside rather than the air flowing along the lower part of the inner surface of the flare portion. Therefore, an eddy current stronger than the lower side is generated on the upper side of the flow of the pumped air ejected from the flare portion, and a negative pressure stronger than that on the lower side is generated. Therefore, buoyancy can be given to the wind pipe by this negative pressure.
Moreover, since the flare part is provided in the exit edge part, pressurized air can be ejected in a wide range.

  According to the invention of claim 5, since the downstream end of the reduced diameter portion is inclined so as to fall downward, the inner diameter upper portion of the reduced diameter portion is smaller in diameter than the inner lower portion. The length from the part that starts to the downstream end becomes longer. Therefore, in the reduced diameter part, the upward force that the upper part of the inner surface receives by the pumped air is larger than the downward force that the lower part of the inner surface receives by the pumped air, so that buoyancy works and gives the wind tube buoyancy. Can do.

  According to the sixth aspect of the invention, since the same configuration as described above is provided, the same effect can be achieved.

[First Embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings.
FIG. 1 is an overall view showing a shoulder-type blower 1 according to this embodiment.
As shown in FIG. 1, the shoulder-type blower 1 of the present embodiment is formed in an L-shape when viewed from the side, and a frame 2 configured to be able to carry the shoulder, and a blower body 3 supported on the frame 2, And a wind pipe 4 connected to the blower body 3.

  The blower body 3 generates pressurized air and pumps the compressed air to the wind tube 4. The blower body 3 includes an engine 31, a centrifugal fan (not shown) that is driven to rotate by the engine 31, a wind tube 4 connected to the outlet portion 321, and the fan inside, and is generated by the rotation of the fan And a volute case 32 for sending the compressed air to the wind tube 4.

  The wind pipe 4 ejects the compressed air fed from the blower body 3 toward the fallen leaves and the like. The wind pipe 4 includes an elbow 41 connected to the outlet 321 of the volute case 32, a snake pipe 42 connected to the elbow 41, an operation pipe 43 connected to the snake pipe 42, and a connection connected to the operation pipe 43. It has a pipe 44 and a nozzle 45 that is connected to the connection pipe 44 and jets out pressurized air that is pumped from the blower body 3 through the members 41 to 44, and has a weight of about 800 g.

A bellows portion 421 is formed in the bellows tube 42. By this bellows part 421, the wind tube 4 can be rotated in an appropriate direction.
An operation grip 431 is attached to the operation tube 43. The operation grip 431 is provided with a throttle lever 432 for adjusting the output of the engine 31. At the time of work, the user operates the throttle lever 432 to adjust the output of the engine 31, holds the operation grip 431, supports the wind tube 4, and directs the wind tube 4 in a desired direction. Pumped air can be ejected in a desired direction.

FIG. 2 is a perspective view showing the nozzle 45, and FIG. 3 is a cross-sectional view showing the nozzle 45.
In such a blower 1, the outlet end portion 5 of the nozzle 45 that ejects the compressed air is reduced in diameter as it goes downstream as shown in FIGS. 2 and 3, and the opening end 51 is the center line of the nozzle 45. It is inclined toward the lower side with respect to L.

FIG. 4 is an enlarged cross-sectional view of the outlet end portion 5 of the wind tube 4 in use.
As shown in FIG. 4, the outlet end portion 5 includes a symmetric cylindrical portion 53 and a modified cylindrical portion 54.
The symmetrical cylindrical portion 53 is formed by cutting a portion from the portion 52 of the outlet end portion 5 where the diameter starts to decrease to the tip thereof by a plane S perpendicular to the center line L so as to include the lowest point Y of the opening end 51. This is a portion that occurs on the upstream side, and has a symmetrical shape with the center line L as the center. Thereby, in the symmetrical cylindrical part 53, the area of the inner surface upper part 531 and the inner surface lower part 532 becomes equal. The inner surface upper portion 531 refers to a portion generated on the upper side when the inner surface of the symmetric cylindrical portion 53 is divided into two by a plane obtained by rotating the horizontal plane so as to be parallel to the center line L, and the inner surface lower portion 532. In this case, it means a portion generated on the lower side. The description of the upper part of the inner surface and the lower part of the inner surface in other members has the same meaning.

  The atypical cylindrical portion 54 is a portion generated on the downstream side when the portion from the portion 52 of the outlet end portion 5 where the diameter starts to be reduced to the tip is cut by the plane S described above, and the upper portion and the lower portion around the center line L. Have an asymmetrical shape. In the modified cylindrical portion 54, the opening end 51 is inclined downward with respect to the center line L, so that the inner surface upper portion 541 has a larger area than the inner surface lower portion 542.

  Since the inner surface upper parts 531 and 541 and the inner surface lower parts 532 and 542 of each of the cylindrical parts 53 and 54 are inclined with respect to the center line L, each of the tubular parts 53 and 54 is subjected to pressure feeding air sent from the blower main body 3. At points, forces F1 and F2 are received in the normal direction n to the tangent plane T of each point. Specifically, the inner surface upper parts 531 and 541 receive an upward force F11 that is the vertical component F11 of the force F1 at each point, and the inner surface lower parts 532 and 542 are the vertical component F21 of the force F21 at each point. A downward force F21 is received.

  In the symmetrical cylindrical portion 53, since the inner surface upper portion 531 and the inner surface lower portion 532 have the same area, the sum F11A of the upward force F11 received by the inner surface upper portion 531 and the sum F21A of the downward force F21 received by the inner surface lower portion 532 are canceled out. The

  However, in the modified cylindrical portion 54, the inner surface upper portion 541 has a larger area than the inner surface lower portion 542, and therefore the total force F11B of the upward force F11 received by the inner surface upper portion 541 is lower than the downward force F21 received by the inner surface lower portion 542. , And the buoyancy F3 acts on the modified cylindrical portion 54. Therefore, in this embodiment, the wind tube 4 can be lightened by the amount of the buoyancy F3, and the burden on the user due to the weight of the wind tube 4 can be reduced. In the present embodiment, the modified cylindrical portion 54 serves as a buoyancy forming portion that applies buoyancy F <b> 3 to the wind tube 4 using the pumped air that is pumped to the wind tube 4.

FIG. 5 is a cross-sectional view showing the outlet end portion 5 of the wind tube 4 in use.
By the way, in the present embodiment, the opening end 51 of the outlet end portion 5 is inclined downward with respect to the center line L of the nozzle 45 as described above. As shown in FIG. 3, the compressed air is ejected slightly downward from the center line L of the nozzle 45. In this embodiment, the opening end 51 is an angle at which the reaction force F4 generated at the action point X1 located at the center of the opening end 51 is directed to the operation grip 431. The opening end 51 is inclined with respect to the center line L of the nozzle 45 at a predetermined angle toward which the reaction force F4 is directed to the gripping point X2, which is the center point of the portion that grips.

  Here, when the opening end 51 is perpendicular to the center line L of the nozzle 45, as shown in FIG. Occurs. In this case, among the reaction force F5, the component force F51 perpendicular to the straight line connecting the action point X1 and the gripping point X2 generates a moment M around the gripping point X2, so that the user gripping the gripping point X2 It will be burdensome.

  On the other hand, in this embodiment, since the reaction force F4 generated at the action point X1 is inclined at an angle toward the gripping point X2, the opening end 51 is inclined at the reaction point F1 toward the gripping point X2. However, it almost occurs. Therefore, since it is possible to suppress the moment M from being generated around the gripping point X2, the burden on the user gripping the gripping point X2 can be reduced.

  The outlet end portion 5 of the present embodiment as described above is reduced in diameter as it goes downstream, and the opening end 51 is merely inclined at a predetermined angle with respect to the center line L of the nozzle 45, so that the configuration is Simple and easy to form. Moreover, since the exit end part 5 is reduced in diameter as it goes downstream, the wind speed of the compressed air can be increased, and cleaning can be facilitated.

[Second Embodiment]
FIG. 6 is a cross-sectional view showing the outlet end 5A of the wind pipe 4A according to the second embodiment of the present invention. Hereinafter, the same functional parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.
The present embodiment is characterized in that a flare portion 7 is provided at the outlet end portion 5A of the wind tube 4A, and this flare portion 7 gives buoyancy F61 to the wind tube 4A. It is assumed that the wind pipe 4A of the present embodiment is also connected to the blower body 3 similar to the first embodiment. The configuration of the wind pipe 4A other than the outlet end 5A is the same as that of the wind pipe 4 of the first embodiment.

As shown in FIG. 6, the outlet end portion 5A of the present embodiment is provided with a diameter-reducing portion 6 that decreases in diameter as it goes downstream, and a downstream stage of the diameter-reducing portion 6, and extends from the diameter-reduced portion 6 toward the downstream side. And a flare portion 7 that expands.
The reduced diameter portion 6 squeezes the pumped air that is pumped from the blower body 3 and increases the flow rate of the pumped air.
The flare portion 7 has an upper side that extends outward from the center line L of the wind pipe 4A more than a lower side.

  When the compressed air is ejected from the outlet end 5A, the air outside the flow is separated from the flow as a vortex, and the vortex is generated around the flow of the compressed air near the outlet end 5A. Arise. At this time, the air A1 flowing along the inner surface upper portion 71 of the flare portion 7 is ejected outward from the center line L, and therefore flows along the inner surface lower portion 72 of the flare portion 7 and ejects in parallel with the center line L. A stronger vortex is generated around the flow of compressed air near the outlet end 5A than the air A2 that is generated.

  The strong eddy current generated near the outlet end portion 5A causes a negative pressure stronger on the upper side near the outlet end portion 5A than the lower side, and the negative pressure causes buoyancy to the outlet end portion 5A. F61 (the upward component force of the force F6 drawn into the negative pressure portion) will act. Therefore, also in this embodiment, the wind tube 4 can be lightened by the buoyancy F61, and the burden on the user due to the weight of the wind tube 4 can be reduced. In the present embodiment, a strong vortex is generated on the upper side in the vicinity of the outlet end portion 5A, and thus a negative pressure is generated, whereby the flare portion 7 that imparts the buoyancy F61 to the outlet end portion 5A becomes the buoyancy forming portion. Further, the flare portion 7 also has a function of increasing the air volume as compared with the case where the outlet end portion 5A is composed of only the reduced diameter portion 6.

[Third Embodiment]
FIG. 7 is a cross-sectional view showing the outlet end portion 5B of the wind pipe 4B according to the third embodiment of the present invention.
The present embodiment is characterized in that the reduced diameter portion 6B provided at the outlet end portion 5B of the wind tube 4B gives the buoyancy F7 to the wind tube 4B.

As shown in FIG. 7, the outlet end portion 5B of the present embodiment is provided with a reduced diameter portion 6B that decreases in diameter as it goes downstream, and a downstream stage of the reduced diameter portion 6B, and extends from the reduced diameter portion 6B toward the downstream side. And a flare portion 7B that expands.
The diameter-reduced portion 6B is inclined such that the downstream end 61, which is the portion with the smallest diameter at the outlet end portion 5B, is tilted downward, and the inner surface upper portion 62 is smaller in diameter than the inner surface lower portion 63. The length from the portion 64 where the diameter of the portion 6B starts to decrease to the downstream end 61 is increased.

  Accordingly, since the upward force F7A received by the pumped air pumped from the blower body 3 at the inner surface upper portion 62 is larger than the downward force F7B received by the pumped air at the inner surface lower portion 63, the reduced diameter portion 6B Buoyancy F7 will work. Therefore, also in this embodiment, the wind tube 4B can be lightened by this buoyancy F7, and the burden on the user due to the weight of the wind tube 4B can be reduced.

[Modification of Embodiment]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
In the third embodiment, the reduced diameter portion 6B is provided at the outlet end portion 5B of the wind tube 4B, but the reduced diameter portion 6B may be provided at an appropriate portion of the wind tube 4B.

FIG. 8 is a cross-sectional view showing a modified wind pipe 4C.
The buoyancy forming unit is not limited to those in the above-described embodiments as long as buoyancy can be imparted to the wind tube using the compressed air that is pumped to the wind tube. For example, as shown in FIG. 8, a buoyancy forming member that has an inclined surface 81 that is inclined with respect to the pumped air (center line L) that is pumped to the wind tube 4C and that is provided on the inner upper surface 46 of the wind tube 4C. The buoyancy formation part may be comprised from 8. Even in this case, since the inclined surface 81 receives the upward force F8 by the compressed air, the buoyancy F8 acts on the wind pipe 4C.

In the said embodiment, although the wind pipes 4, 4A, 4B were used for the shoulder type blower, you may be used for the hand-held type or the walk-behind type blower.
In the said embodiment, although the wind pipes 4, 4A, 4B were used for the cleaning blower which ejects only pressurized air, the wind pipes 4, 4A, 4B spray chemicals, such as a herbicide, by pressurized air. It may be used for a blower for spraying medicine.

  The present invention can be used for blower wind tubes and blowers.

1 is an overall view showing a blower according to a first embodiment of the present invention. The perspective view which shows a nozzle. Sectional drawing which shows a nozzle. Sectional drawing which expands and shows the exit end part of the wind pipe at the time of use. Sectional drawing which shows the exit edge part of the wind pipe at the time of use. Sectional drawing which shows the exit end part of the wind pipe which concerns on 2nd Embodiment of this invention. Sectional drawing which shows the exit end part of the wind pipe which concerns on 3rd Embodiment of this invention. Sectional drawing which shows the wind pipe of a modification.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Blower, 3 ... Blower main body, 4, 4A, 4B, 4C ... Wind pipe, 5, 5A ... Outlet end part, 6B ... Reduced diameter part, 7 ... Flare part, 51 ... Open end, 54 ... Atypical cylindrical part , 62, 531... Upper part of the inner surface, 63, 532... Lower part of the inner surface, 431... Operation grip, L.

Claims (6)

A blower wind pipe,
A blower wind tube, comprising: a buoyancy forming unit that imparts buoyancy to the wind tube using compressed air that is pumped to the wind tube. In the blower wind pipe according to claim 1,
The outlet end portion of the wind pipe is reduced in diameter as it proceeds downstream, and the opening end is inclined downward, and the outlet end portion includes the lowest point of the opening end. Provided with an atypical cylindrical part that occurs on the downstream side when cut by a plane perpendicular to the center line,
The atypical cylindrical portion is the buoyancy forming portion, and the upward force received by the upper surface of the inner surface by the compressed air is larger than the downward force received by the lower surface of the inner surface by the compressed air, whereby the wind tube Blower wind tube characterized by giving buoyancy to In the blower wind pipe according to claim 2,
An operation grip is provided for the user to grip and support the wind tube,
The blower wind tube, wherein the opening end is inclined at an angle that a reaction force generated when the compressed air is ejected downward from the opening end toward the operation grip. In the blower wind pipe according to claim 1,
A flare portion that expands toward the downstream side is provided at the outlet end of the wind pipe,
The flare portion is the buoyancy forming portion, and the upper side is spread outward from the center line of the wind tube than the lower side, and a larger eddy current is generated on the upper side than the lower side when jetted air is ejected. A blower wind tube characterized by imparting buoyancy to the wind tube. In the blower wind pipe according to any one of claims 1 to 4,
The wind pipe includes a reduced diameter portion that decreases in diameter as it proceeds downstream.
The reduced diameter portion is the buoyancy forming portion, and is inclined so that the downstream end is tilted downward. The upward force received by the upper portion of the inner surface by the pressurized air is received by the lower portion of the inner surface by the pressurized air. A blower wind tube characterized by giving buoyancy to the wind tube by becoming larger than a downward force. A blower body that generates and feeds compressed air; and a wind pipe that is connected to the blower body and that blows out the compressed air that is pumped from the blower body.
The blower is a blower of the blower according to any one of claims 1 to 5. The blower according to any one of claims 1 to 5.

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