JP3668413B2 - Axial flow fan with multi guide vane - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an axial flow type blower, and more particularly to a portable forced cooling fan.
[0002]
[Prior art]
Conventionally, portable axial fans have been frequently used for ventilation of facilities and rooms or cooling of hot objects. As shown in FIG. 7, these blowers 101 are radial guide vanes provided in the radial direction on the downstream side of the rotary fan 160 in order to suppress the swirling of the outflow airflow and reduce the loss of velocity energy of the outflow airflow. Many have 103.
[0003]
[Problems to be solved by the invention]
However, the conventional radial guide vane alone cannot prevent the outflow airflow from spreading radially in a cone shape from the outlet of the blower. For this reason, when cooling a hot object such as a casting at a predetermined distance from the blower, the flow velocity of the cooling airflow hitting the hot object decreases, and if the cooling object is small, only a part of the wake will contact the cooling object. Therefore, there is a problem that the cooling efficiency is extremely deteriorated. Furthermore, it is necessary to suppress the spread of the outflow airflow even when a gas containing dust or moisture is exhausted by a blower and the exhausted air is applied to a predetermined filter or the like to remove contents such as dust or moisture. It was.
[0004]
Accordingly, an object of the present invention is to provide an axial-flow fan equipped with a multi-guide vane that not only suppresses the swirling of the outflow airflow but also can suppress the radial spread of the outflow airflow in order to solve the above problems. Is.
[0005]
[Means for Solving the Problems]
The blower according to the present invention has a multi-guide vane on the downstream side of the rotary fan of the axial flow blower, and rectifies the outflow airflow by the multi-guide vane. This multi-guide vane includes a radial guide vane provided in the radial direction that suppresses the swirling of the outflow airflow, and a ring guide vane provided in the circumferential direction that suppresses the radial spread of the outflow airflow . The radial guide vane has a plurality of stationary blades, is fixed at a position close to the downstream side of the rotary fan, and is set at an angle that cancels the swirling of the airflow flowing out of the rotary fan. The ring guide vane includes a ring vane formed of a plurality of ring-shaped thin plates formed concentrically and a plurality of struts provided radially to hold the ring vane. In order to further suppress the radial spread of the outflow airflow, the mounting angle is inclined so that the ring radius of the ring vane trailing edge is reduced .
[0006]
A rotary fan of an axial-flow fan has a plurality of rotor blades driven by a built-in motor. The radial guide vane constituting the multi-guide vane is composed of a plurality of stationary blades, and is fixed to at least one of the outer casing and the inner casing of the blower at a position close to the downstream side of the rotary fan, and flows out of the rotary fan. It is set to an angle that cancels the turn. In the case of changing the set rotational speed of the blower, it is effective to use a variable stationary blade that can change the attachment angle of the blade.
[0007]
The ring guide vane constituting the multi-guide vane includes a ring vane formed of a plurality of concentric ring-shaped thin plates and a plurality of struts provided in a radial shape for holding the ring vane. The ring vane has a cross-sectional shape of a thin plate having a front edge and a rear edge having an arc cross section.
[0008]
The ring vane mounting angle is set so that the center line in the longitudinal direction of the cross section of the ring vane is parallel to the rotation axis, ie, the radial direction of the outflow air flow of the blower. In order to further suppress the spread of the ring vane, the angle of the ring vane is tilted so that the ring radius of the ring vane trailing edge decreases. The ring guide vanes are attached to one or both of the outer casing and the inner casing of the blower.
[0009]
Next, the function and operation of this multi-guide vane will be described. The airflow from the rotor blades of the rotating fan is turned into a swirling flow by the rotation of the fan and flows into the stationary blade row of the radial guide vane in the wake. The inflowing airflow is changed in the circumferential flow angle in the stationary blade row, and the swirling of the flow is suppressed to flow out. However, it is difficult to completely cancel the swirling of the airflow flowing out from this radial guide vane, and this outflowing air has a radial velocity component. It spreads in the direction and flows. On the other hand, when the ring guide vane according to the present invention is provided, the airflow that has flowed into the ring guide vane is forcibly rectified into a parallel flow by the ring guide vane and flows out. Therefore, the outflow airflow that has passed through the multi-ring vane of the present invention becomes a flow in which swirling and radial spread are suppressed. As a means for suppressing the spread of the outflow airflow, there is a means for providing a cylindrical duct at the outlet of the blower. However, since it is necessary to secure the length of the duct to some extent, storage, transportation or It becomes inconvenient in handling.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The cross-sectional structure of the blower of the present invention is shown in FIG. 1, and the back structure is shown in FIG. The blower 1 includes an axial-flow rotary fan 60 concentric with the outer casing 50 and a multi-guide vane 2 positioned in the vicinity of the wake of the rotary fan. The multi-guide vane 2 includes a radial guide vane 3 composed of a plurality of blade rows extending radially in the radial direction and a concentric ring guide vane 4 positioned in the downstream.
[0011]
The axial-flow rotary fan 60 has a plurality of moving blades 61 formed of cast aluminum or synthetic resin, and is driven by a motor 80 supported on the outer casing 50 by a plurality of radial stays 70. . The rotor blade 61 is provided around the outer diameter portion of the disc-shaped hub 62. The radial guide vane 3 is composed of a plurality of stationary blades 31 made of cast aluminum or synthetic resin, and support shafts provided at the outer and inner end portions of the blade along the radial central axis of the blade. 32 and 33 are rotatably attached to the outer casing 50 and the inner casing 90.
[0012]
The ring guide vane 4 is integrally formed from aluminum sheet metal welding or synthetic resin material, and includes a plurality of concentric ring vanes 41 and a plurality of radial struts 42 that hold the ring vanes. The ring vane 41 is formed of a thin flat plate having a front end portion and a rear end portion having an arc cross section, and is set to be parallel to the central axis of the blower 1. An outer case 43 is provided on the outer peripheral portion of the strut 42 and an inner case 44 is provided on the inner peripheral portion. The outer case 43 is inserted into the inner periphery of the outer casing 50 and the outer periphery of the inner casing 90, respectively. Further, the outer case 43 is fixed to the rear end flange portion of the outer casing 50 by a coupling band 55 having a V-shaped cross section, and is easily attached and detached.
[0013]
Here, FIG. 3 shows a cross section in which the rotating fan 60, the radial guide vane 3 and the ring guide vane 4 are cut along the circumferential surface and horizontally developed. The airflow C1 flowing into the rotor blade 61 of the rotary fan 60 flows out as an airflow W2 (relative speed with respect to the rotor blade) along the trailing edge of the rotor blade, and the swirling airflow C2 to which the rotation speed U of the rotor blade 61 is added. It flows into the stationary blade 31 of the radial guide vane 3 as (absolute speed). The inflowing airflow C2 is changed in the flow direction in the circumferential direction by the stationary blade 31 and flows out as the airflow C3 whose swirling is canceled and flows into the ring vane 41. The airflow C3 is forced to flow into the airflow C4 parallel to the axis by the ring vane 41 and flows out.
[0014]
Therefore, the multi-guide vane 2 of the present invention suppresses swirling and radial spread of the airflow C4 flowing out from the blower 1 as shown in FIG. 4, and can efficiently apply cooling air to the object to be cooled. .
[0015]
Next, a mechanism for changing the mounting angle of the stationary blade 31 is shown in FIGS. A support shaft 32 provided at the outer end portion of the stationary blade 31 passes through a hole 50a formed in the outer casing 50, and a lever vane 34 is attached to the outer end portion thereof substantially parallel to the casing surface. A pin 35 is provided at the other end of the lever vane 34, and this pin is inserted into a slot 36a of a guide ring 36 that is provided so as to be rotatable around the outer surface of the outer casing 50. Therefore, the attachment angle of the stationary blade 31 is changed by rotating the guide ring 36 and rotating the lever vane 34 around the support shaft 32 through the slot 36a and the pin 35 formed in the guide ring.
[0016]
The axial-flow rotary fan 60 may be driven by a motor or an internal combustion engine installed outside the blower 1 via a torque transmission mechanism. When it is necessary to shorten the axial length of the ring guide vane 4, the number of ring vanes 41 is increased to enhance the rectification effect of the airflow passing between the ring vanes. Further, when the airfoil cross-sectional shape is adopted for the ring vane 41, the loss of the outflow airflow can be reduced.
[0017]
【The invention's effect】
By providing the multi-guide vane having the above-described structure, not only the swirling of the outflow airflow of the blower but also the radial spread can be suppressed, so that the efficiency of forced cooling and dust removal by the blower can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional structural view of a blower.
FIG. 2 is a rear structural view of the blower.
FIG. 3 is an enlarged development view in which a multi-guide vane is cut along a circumferential direction.
FIG. 4 is a side view showing a state of airflow flowing out from the blower.
FIG. 5 is an enlarged cross-sectional view showing a mechanism for changing a mounting angle of a radial guide vane.
FIG. 6 is an enlarged top view showing a mechanism for changing a mounting angle of the radial guide vane.
FIG. 7 is a cross-sectional structure diagram of a conventional blower.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,101 Blower 2 Multi guide vane 3, 103 Radial guide vane 31 Stator blade 4 Ring guide vane 50 Outer casing 60, 160 Axial flow type rotary fan 61 Rotor blade 70 Stay 80 Motor 90 Inner casing

Claims (1)

A blower having an axial flow type rotary fan and a multi- guide vane that rectifies the outflow airflow on the downstream side,
The multi- guide vane is located in a radial guide vane provided in the radial direction that suppresses the swirling of the outflow air flow, and a circumferential direction that suppresses the radial spread of the outflow air flow of the radial guide vane. consists of a ring guide vanes provided in the direction,
The radial guide vane has a plurality of stationary blades, is fixed at a position close to the downstream side of the rotary fan, and is set at an angle that cancels the swirling of the airflow flowing out of the rotary fan,
The ring guide vane is composed of a plurality of ring-shaped thin plates formed concentrically and a plurality of struts provided radially to hold the ring vane,
The ring vane, in order to suppress more the radial extent of the outflow stream multi guide vaned axial flow, characterized in that the mounting angle ring radius of the ring vane trailing edge is inclined so as to reduce Blower.

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