JPH05149298A - Air separator of axial flow air separator - Google Patents

Abstract

PURPOSE:To prevent deterioration in efficiency in a sound operating territory except a stalling point while maintaining stall improving property. CONSTITUTION:A casing 13 is divided into many small segments along its circumferential direction, and vane bodies 17 constituted by thread-mounting first vane elements 15 and second vane elements 16 through pins 22 are provided in space parts formed among them. When a blower is operated far away from a stalling territory, the vane bodies 17 are placed into the condition shown with the full line in the figure so as to nearly conform the inner face of the first elements 15 to the inner face of the casing 13 in the circumferential direction and close the opening part of the casing 13 serving as the inlet of an air separator. Meanwhile when the operating territory approaches the stalling territory, a motor is driven, an outer ring 20 is rotated in the circumferential direction through a pinion 27 and a gear 24, the vane bodies 17 are lifted as shown with the two dotted chain line in the figure, so as to open the opening part of the casing 13 and form an air separator flow passage through a recessed part 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air separator for an axial blower, and more particularly to a structure of a radial vane type air separator that contributes to improving the stall of the axial blower.

[0002]

2. Description of the Related Art FIGS. 6 to 8 are views showing an example of the structure of a conventional radial vane type air separator. In these figures, in the casing 2 that is provided on the outer periphery of the rotor blade 1 of the axial fan, the portion of the casing 2 that faces the tip of the rotor blade 1 is recessed from the vicinity of the front edge of the rotor blade 1 toward the upstream side. The circulation passage 4 is formed by forming the place 3. Further, a large number of vanes 5 for swirling and removing are arranged in parallel in the circumferential direction at a position closest to the tip of the first moving blade 1 inside the circulation flow path 4. This eliminates the drawback that the pressure sharply drops at the stall point, and allows the degree of the stall margin to be estimated. In FIG. 6, reference numeral 6
Is a hub, and 7 is a ring.

[0003]

However, in the conventional air separator described above, since the recess 3 is generally open toward the mainstream part of the blower, a part of the mainstream A is indicated by the arrow B. As shown, there was a problem of constant leakage and circulation. Therefore, there is a tendency that the efficiency of the blower other than near the stall point is reduced. And this reduction in efficiency could reach several percent.

The present invention has been made in order to solve the problems of the prior art as described above, and it is possible to prevent a decrease in efficiency in a sound operating region other than the stall point while maintaining the stall improving property. An object is to provide an air separator for a blower.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention relates to a casing of a casing which is provided on the outer periphery of a rotor blade of an axial blower, the casing blade facing the tip of the rotor blade. In an air separator having a recess formed on the upstream side, a vane body is arranged in each of a plurality of openings formed in the circumferential direction of the casing, and one end of the vane body has a casing whose inner surface is the casing. The vane body is supported so as to substantially coincide with the inner surface of the vane in the circumferential direction, and the other end of the vane body is connected to the outer ring rotatable in the circumferential direction.

[0006]

According to the above means, when the blower is operating away from the stall area, the opening of the casing serving as the air separator inlet is closed by the vane body, and the inner surface of the vane body is made the inner surface of the casing. By making them substantially coincident with each other, the circulating flow in the air separator is eliminated. Therefore, since the power for generating the circulating flow does not become a loss, a highly efficient operation of a normal blower is achieved. On the other hand, when approaching the stall region, the outer ring is rotated in the circumferential direction to pull up the vane body, open the opening of the casing, and form the air separator flow path, whereby the stall improving effect can be exhibited. Become.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sectional view of a main part showing an air separator of an axial blower according to a first embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a perspective view of a vane body according to the present embodiment. It is a figure.

In these figures, a casing 13 is provided on the outer periphery of a rotor blade 12 mounted around the hub 11, and the casing 1 is opposed to the tip of the rotor blade 12.
A concave portion 14 is formed on the upstream side from the moving blade 12 in the portion of No. 3. As shown in detail in FIG. 2, the casing 13 is divided into a large number of small segments in the circumferential direction,
A space is formed between them, and each space has two flat plate-shaped vanes No. 1 as shown in detail in FIG.
A vane body 17 is provided, which is configured such that the element 15 and the second vane element 16 are hinged via a pin 22 and can be bent.

Then, one end of the vane body 17, that is, the free end of the vane first element 15 is at the vane first element 1
The inner surface of 5 is supported via a pin 18 (hanging between the casing 13 and the air separator ring 19) that extends in the axial direction so as to substantially match the inner surface of the casing 13 in the circumferential direction. The other end of the vane body 17, that is, the free end of the second vane element 16 is connected to the outer ring 20 rotatable in the circumferential direction via a pin 21 extending in the axial direction.

On the other hand, the recess 14 is formed on the upstream side of the moving blade 12 by the casing 13 and the air separator channel wall 23, and an air separator ring 19 having the same radius as the casing 13 is provided in the recess 14. The air separator ring 19 is arranged so as to secure a flow path on the downstream side. Further, the outer ring 20 is rotatably provided in the recess 14, and a gear 24 is attached to a part of the outer ring 20 so that the gear 24 is projected outside from the opening 23A of the air separator channel wall 23. It is configured as follows. A motor 25 is arranged outside the air separator channel wall 23, and a pinion 27 that meshes with the gear 24 via a shaft 26 is attached.

Further, as shown in detail in FIG. 3, the vane body 17 is composed of a flat vane first element 15 and a vane second element 15.
The element 16 is hinged by a pin 22, and the other ends of the vane first element 15 and the vane second element 16 are rotatably attached to the pins 18 and 21, respectively.

Next, the operation of this embodiment will be described.
In FIG. 2, in the normal case where the blower is operating away from the stall zone, the vane first element 15 and the vane second element 15 are
The vane body 17 composed of the element 16 and the element 16 is placed in the posture shown by the solid line, and the inner surface of the vane first element 15 substantially coincides with the inner surface of the casing 13 in the circumferential direction to form the same circumferential surface as a whole. As a result, the opening of the casing 13 serving as the air separator inlet is closed. This is the outer ring 2
This is accomplished by setting the 0 position to the appropriate position. As a result, there is no decrease in the performance of the blower when it is sound.

On the other hand, when approaching the stall point, an instruction is externally or automatically given to the motor 25 to rotate the outer ring 20 in the circumferential direction. As a result, the vane body 17 changes its position and shape as shown by the chain double-dashed line in FIG. As a result, the opening of the casing 13 is opened and forms an angle with the circumferential direction. Therefore, a part of the flow on the tip side of the blower is scooped up, the circulating flow passes through the air separator flow path as indicated by arrow C in FIG. 1, is rectified in the axial direction, and returns to the main flow D again. This achieves stall improvement.

Next, FIG. 4 shows a second embodiment of the present invention.
Another example of a vane body is shown. In this embodiment, the vane body is made of one arc-shaped plate 17 '(preferably an elastic plate),
Both ends thereof are connected to the casing 13 and the outer ring 20 via pins 18 and 21, respectively, so that when the vane body 17 'is closed, it forms a complete circumferential wall as shown by the solid line.

FIG. 5 shows a third embodiment of the present invention.
In this embodiment, the structure of the vane body 17 is the first one described above.
Same as the embodiment, except that the casing 13 is used as an opening.
A different point is that slits 28 formed in the axial direction are formed in the slits and the vanes 17 are provided in these slits 28.

A stationary blade (not shown) located immediately upstream of the moving blade 12 has a variable pitch structure, and the change in the variable pitch angle and the opening / closing of the vane body are combined in a certain suitable relationship. Good.

[0017]

As described above, according to the air separator of the axial blower according to the present invention, when the blower is operating at a position separated from the stall region, the inner surface of the vane is the inner surface of the casing. The vane body closes the casing opening that serves as the air separator inlet, making them nearly coincident with each other in the circumferential direction, which makes it possible to eliminate the circulating flow in the air separator and prevent the loss of power that generates the circulating flow. Yes, it is possible to achieve high efficiency operation of conventional blowers. Further, when the blower approaches the stall region, the outer ring is rotated in the circumferential direction to pull up the vane body, and the opening of the casing is opened to form the air separator flow passage, which can exhibit the stall improving effect. it can. Therefore, according to the present invention, it is possible to achieve a high efficiency and a high operating range, and it is possible to realize an extremely easy-to-use axial blower.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing an air separator of an axial flow fan according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a perspective view of a vane body according to the present embodiment.

FIG. 4 is a schematic configuration diagram showing another example of a vane body as a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of essential parts showing an air separator of an axial flow fan according to a third embodiment of the present invention.

FIG. 6 is a partial cross-sectional view showing an example of an air separator of a conventional axial flow fan.

FIG. 7 is an operation explanatory diagram of FIG. 6;

8 is a partially enlarged perspective view of FIG.

[Explanation of symbols]

 Reference Signs List 12 rotor blade 13 casing 14 recess 15 vane first element 16 vane second element 17 vane body 17 'vane body 20 outer ring 23 air separator channel wall 25 motor

Claims (1)

[Claims] 1. An air separator in which a casing is provided on the outer periphery of a moving blade of an axial blower, and a recess is formed upstream from the moving blade of a casing portion facing the tip of the moving blade. A vane body is provided in each of a plurality of openings formed in the circumferential direction, and one end of the vane body is supported so that the inner surface of the vane body is substantially aligned with the inner surface of the casing in the circumferential direction, and the vane body is supported. An air separator for an axial blower, the other end of which is connected to an outer ring rotatable in the circumferential direction.