JP3725846B2 - Bellmouth connected to blower wind tunnel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bell mouth connected to an air suction port side of a wind tunnel portion constituting a blower.
[0002]
[Prior art]
FIG. 4 is a cutaway cross-sectional view of the main part showing a state in which the bell mouth 2 is attached to the cylindrical wind tunnel portion 1 constituting the blower. Reference numeral 3 denotes a blade. The bell mouth 2 is attached to the curled edge 1a of the wind tunnel portion 1 and has a trumpet shape that expands toward the outside in order to smoothly suck air by the rotation of the blade 3, and the connecting portion of the bell mouth 2 is It is branched in a bifurcated manner, and the edge 1a of the wind tunnel portion is sandwiched between the outer edge 2a on the outer side and the inner edge 2b on the inner side and attached.
[0003]
[Problems to be solved by the invention]
Since the inner edge 2b of the bell mouth 2 is deeply inserted into the air suction side inner edge of the wind tunnel portion 1, a step is generated between the end surface of the inner edge 2b and the inner peripheral surface of the wind tunnel portion 1 at the connection portion. In the inner edge 2b, the inner diameter of the wind tunnel portion 1 is reduced, the cross-sectional area is reduced, the air volume is lost, and the sucked airflow becomes a spiral flow at the stepped portion, preventing the airflow from flowing smoothly and generating noise. . Then, the bell mouth which concerns on this invention aims at improving a ventilation performance and a quiet performance by devising an ingenuity in a connection part, reducing an air volume loss and a turbulent flow (vortex flow).
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is configured to include the following problem solving means.
[0005]
The invention described in claim 1 includes a motor 8 supported by a support plate 7 in a wind tunnel portion 6 of a portable blower 5 shown in FIGS. 1, 2, and 3, a blade 9, an air suction side, and air. Conventionally, the safety guard 10 is provided on the discharge side, the hand 11 is provided at the upper part of the wind tunnel part 6, and the mount 12 is provided at the lower part.
[0006]
The trumpet-shaped bell mouth 13 that is detachably mounted on the edge 6a of the wind tunnel portion 6 that is the most characteristic of the present invention has a bifurcated shape on the reduced diameter side, and holds the edge 6a curled outward. A recess 13a is formed. The recess 13a is formed by a long outer edge portion 13b and a short inner edge portion 13c.
[0007]
Since the present invention is configured as described above, the air 14 introduced by the bell mouth 13 and sucked into the wind tunnel portion 6 is sucked into the smooth air without generating a spiral flow at the suction port of the wind tunnel portion 6 and is blown. Reduce noise.
[0008]
Further, since the inner edge 13c of the bell mouth does not protrude into the wind tunnel portion 6, the inner diameter of the wind tunnel portion is not reduced and the cross-sectional area is not reduced, so that the loss of air volume can be prevented.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The best mode of the present invention will be described with reference to the drawings.
[0010]
FIG. 3 is a perspective view of the blower 5 according to claim 1. The blower 5 includes a cylindrical wind tunnel portion 6 and a motor 8 and a blade 9 which are held by a support plate 7 which also serves as a stationary blade hanging down from the inner peripheral wall of the wind tunnel portion 6. Safety guards 10 are stretched on the air discharge side, 11 is a lender, and 12 is a stand. These structures are conventionally known. A trumpet-shaped bell mouth 13 is detachably attached to the edge 6a of the wind tunnel curled outwardly outside the safety card 10 on the air suction side. The present invention has the feature in the mounting portion of the bell mouth 13 to be mounted on the blower 5. That is, as shown in the enlarged view of the cutout of the main part shown in FIG. 2, the mounting portion of the bell mouth 13 is configured to cover the end edge 6a of the wind tunnel portion and be elastically sandwiched. The recess 13a for sandwiching the end edge 6a is formed of a bifurcated outer outer edge portion 13b and an inner inner edge portion 13c on the reduced diameter side of the bell mouth 13, and the outer edge portion 13b is formed as an inner edge. When the bell mouth 13 is mounted on the air suction side of the wind tunnel 6 when the inner diameter of the inner edge is substantially the same as the inner diameter of the end of the wind tunnel and the bell mouth 13 is mounted on the air suction side of the wind tunnel 6 It is characterized in that the connecting portion of the bell mouth 13 is formed into a gentle curved surface that does not form a spiral flow. Since the inner edge 13c does not protrude toward the air suction side of the wind tunnel 6 on the inner peripheral surface of the bell mouth 13, the air 14 sucked along the bell mouth 13 does not generate a swirl at the wind tunnel entrance. It is smoothly sucked into the wind tunnel portion 6 without causing a loss of air volume. Further, since the inner edge portion 13c of the bell mouth 13 does not protrude into the wind tunnel portion 6, the inner diameter of the air tunnel portion 6 on the side of the air suction port is not reduced, so that the cross-sectional area does not decrease, and therefore the suction air volume can be blown without loss.
[0011]
【The invention's effect】
Since the bell mouth mounting portion does not protrude into the wind tunnel portion, the air can be blown without causing a smooth and airflow loss, and the air can be blown with a reduced pressure loss, thereby improving the blowing performance and the quiet performance.
[Brief description of the drawings]
FIG. 1 is an upper half cross-sectional view showing a configuration of a bell mouth mounted on an air suction side of a blower according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part of the bell mouth mounting portion.
FIG. 3 is an external perspective view of a blower equipped with a bell mouth.
FIG. 4 is an enlarged cross-sectional view of a main part of a conventional bell mouth mounting part.
[Explanation of symbols]
5, blower 6, wind tunnel part 6a, curled edge 13 of the wind tunnel part, bell mouth 13b, outer edge part 13c, inner edge part

Claims (1)

In the bell mouth that is detachably attached to the curled edge of the wind tunnel constituting the blower, the bell mouth connecting part is formed in a bifurcated shape, the outer edge is longer than the inner edge, and the inner diameter of the inner edge is Connected to the wind tunnel part of the blower, which is formed to be approximately the same diameter as the inner edge of the wind tunnel edge, and when the bell mouth is attached to the air suction side of the wind tunnel part, the sucked airflow does not become a spiral flow at the connection part Bellmouth to do.

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