JP4396952B2 - Impeller for sirocco fan - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an impeller for a sirocco fan that is configured by double-wrapping a blade plate formed by projecting a plurality of blades at equal intervals in a cylindrical shape.
[0002]
[Prior art]
A sirocco fan, which is a type of centrifugal fan, has a cylindrical impeller that is driven to rotate in a casing, and can be operated in a wide flow range, so it is widely used as a home or industrial ventilation fan. Yes.
[0003]
In order to increase the static pressure capacity of such a sirocco fan, it is effective to increase the total area of the blades by increasing the number of blades of the impeller.
[0004]
However, when the blades are formed by cutting and raising the metal plate, the number of blades is naturally limited because the blade pitch is determined from the height of the blades.
[0005]
Therefore, an impeller is configured by winding two blades formed by projecting a plurality of blades at equal pitches by cutting and raising them into a belt-shaped metal plate, and winding them into a cylindrical shape twice. A proposal has been made to increase the static pressure capacity of a sirocco fan by doubling the number of blades (halving the blade pitch) (see JP-A-3-125000).
[0006]
[Problems to be solved by the invention]
However, in the impeller according to the above proposal, when two slats are double-rolled into a cylindrical shape, a difference in thickness between the inner and outer slats occurs, so that either the inner or outer slats. There was a problem that distortion occurred and it was impossible to keep the blade pitch at regular intervals.
[0007]
In addition, since the two blades that are double-wound are not connected, there is a problem that the impeller body has insufficient rigidity and the impeller rotational strength is weak.
[0008]
In addition, since a ring is necessary for fixing both ends of the double-wrapped blade plate in the axial direction, there is a problem that the number of parts increases and the impeller increases in weight and costs.
[0009]
Therefore, the object of the present invention is for a sirocco fan that can double the number of blades without changing the shape and machining dimensions of the blade plate, and can increase the static pressure capability by keeping the blade pitch at equal intervals. To provide an impeller.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the invention described in claim 1 is characterized in that a cylindrical impeller body is obtained by double winding an impeller formed by projecting a plurality of blades at equal intervals by cutting and raising a belt-shaped metal plate. in sirocco fan impeller formed by configuration, a plurality of cut on two widthwise ends of the blades separate the same size and the same shape raised alternately formed projections and grooves in the longitudinal direction, the two equidistant a plurality of vanes of the vane plate with wound doubly cylindrical constitute the impeller body inside the cut-and-raised projection so as to fit on the outside of the groove, the inner circumference of the impeller body of It is characterized by projecting into
[0013]
The invention according to claim 2 is for a sirocco fan in which a cylindrical impeller body is formed by double winding an impeller formed by cutting and raising a plurality of blades at equal intervals by cutting and raising a belt-shaped metal plate . In an impeller, a plurality of cut-and-raised protrusions and grooves are alternately formed in the longitudinal direction at both ends in the width direction of one blade plate, and the inner blade-and-raised protrusion is fitted into an outer groove. In this manner, the impeller body is configured by continuously double-winding, and a plurality of blades are provided at regular intervals on the inner periphery of the impeller body .
[0018]
Therefore, according to the invention of claim 1 Symbol placement, by double-wrap the separate two blades of the same size and the same shape formed by projecting a plurality of blades equally spaced, also, according According to the invention described in Item 2, the number of blades can be doubled without changing the shape and processing dimensions of the blades by continuously doubling one blade, and overlapping The inner and outer slats are positioned securely by cutting and raising and fitting into the grooves of the projections. Since the difference is absorbed and the pitch of the blades is kept at an equal interval, the static pressure capability of the impeller can be increased.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0022]
1 is a partial plan view of the slats, FIG. 2 is a partial side view of the slats (a view in the direction of arrow A in FIG. 1), and FIG. 3 is a front view of the slats in the direction of arrow B in FIG. 4) is a partial perspective view of the inner and outer two blades, FIG. 5 is a partial side sectional view showing a state in which the inner and outer blades are overlapped, and FIG. 6 is a double view of the inner and outer blades. FIG. 7 is a perspective view of an impeller body, FIG. 8 is a longitudinal sectional view of an impeller for a sirocco fan according to the present invention, and FIG. 9 is an enlarged detail view of part C of FIG.
[0023]
1 to 4 is a blade plate (an inner impeller to be described later) 1 in which a plurality of blades 2 are integrally projected on the same side at an equal interval pitch P by cutting and raising a belt-like metal plate by press molding. It is configured. In the blade 1, each blade 2 is formed in an arcuate curved shape, and a long rectangular space S formed by cutting and raising each blade 2 in the axial direction (vertical direction in FIG. 1) between adjacent blades 2. Is formed.
[0024]
And the flange part 1a is formed in the width direction edge of the both sides of the blade | wing 2 of the said blade board 1 along a length direction (left-right direction of FIG. 1), and several cut-and-raising is carried out in each flange part 1a. The protrusions 3 and the rectangular grooves 4 are alternately formed at an equal interval pitch ((P / 2) half of the blade pitch P).
[0025]
Each of the cut-and-raised protrusions 3 is formed at an intermediate position in the arrangement direction of the adjacent blades 2 (the left-right direction in FIG. 1), and the cut-and-raised protrusion 3 is cut and raised on the inner side in the width direction of the cut-and-raised protrusion 3. A notch groove 5 is formed, and the notch groove 5 opens into the space S formed between adjacent blades 2. Each groove 4 is formed in a rectangular shape that is long in the length direction in accordance with the cross-sectional shape of each cut and raised protrusion 3.
[0026]
Thus, as shown in FIG. 4, the inner and outer two blade plates 1 and 1 'having the same dimensions and the same shape as described above are long by a pitch (P / 2) which is half the blade pitch P. Overlapping in the vertical direction. Then, as shown in FIG. 5, the blade 2 ′ of the outer (upper) blade plate 1 ′ enters the space S between the adjacent blades 2 through the notch groove 5 of the inner (lower) blade plate 1. The blades 2 of the inner (lower) blade plate 1 enter the space S between the blades 2 ′ of the outer (upper) blade plate 1 ′ and project from the inner (lower) blade plate 1. The cut-and-raised protrusion 3 is inserted into the groove 4 ′ of the outer (upper) blade plate 1 ′ from below and fitted. By fitting the cut-and-raised protrusion 3 into the groove 4 ', the two inner and outer blades 1 and 1' are overlapped and reliably shifted in the length direction by a half (P / 2) pitch of the blade pitch P. The blades 1, 2 'formed on each of the blade plates 1, 1' are alternately arranged at a pitch of (P / 2) on the two inner and outer blade plates 1, 1 'positioned and superimposed on each other. The total number of blades 2 and 2 'doubles.
[0027]
Next, as shown in FIG. 5, the two inner and outer blades 1, 1 ′ overlapped in a cylindrical shape with the blades 2, 2 ′ inside, and each blade 1, 1 ′ is wound. The end portions of the flange portions 1a and 1a ′ are butted against each other and welded. Here, there is a difference in plate thickness between the radii of the two inner and outer blades 1 and 1 ′ wound in a cylindrical shape, but the two inner and outer blades 1 and 1 ′ are overlapped with each other as described above. Thus, since the outer blade 1 'is stretched in the circumferential direction, the thickness of the two blades 1, 1' is equal to the thickness The difference in the circumferential length due to the difference is absorbed, and the pitch of the blades 2 and 2 'is kept at an equal interval of (P / 2). The end portions of the flange portions 1a and 1a 'of the double-wrapped blades 1 and 1' may be joined by caulking or other means.
[0028]
Thereafter, a portion where the cut and raised protrusion 3 formed on the inner blade 1 protrudes from the groove 4 ′ formed on the outer blade 1 ′ is bent outward as shown in FIG. 1 'is connected at both ends. It should be noted that the cut and raised protrusion 3 may be bent at the overlapping stage (the state shown in FIG. 5) before double-winding the blades 1 and 1 ', and the cut and raised protrusion 3 is bent inward. May be.
[0029]
Thus, both end portions in the axial direction (end edges of the flange portions 1a and 1a ′) of the two inner and outer blades 1 and 1 ′ that are double-wound in a cylindrical shape are formed by curling as shown in detail in FIG. It is bent outwardly, joined and integrated, and end processing is performed, so that a cylindrical impeller body 6 as shown in FIG. 7 is obtained. Then, on the inner peripheral side of the impeller body 6, the blades 2 and 2 ′ are alternately arranged in the circumferential direction at equal intervals ((P / 2) pitch).
[0030]
The disk-shaped back plate 7 as shown in FIG. 8 is fixed to the central portion in the axial direction inside the cylindrical impeller body 6 shown in FIG. The fan impeller 10 is obtained, and the impeller 10 is fixed by a fixing bolt 9 to a rotating shaft (not shown) inserted through a boss 8 fixed to the center of the back plate 7.
[0031]
Thus, in the sirocco fan, the impeller 10 is accommodated in a casing (not shown), and the impeller 10 is sucked from the suction port of the casing by being rotated at a predetermined speed by an electric motor (not shown). Air is sucked in from the opening at both ends of the impeller 10 in the axial direction (left-right direction in FIG. 8) and pressurized, and the pressurized air is discharged in the radial direction and discharged from the discharge port of the casing.
[0032]
In the above, in the sirocco fan impeller 10 according to the present invention, the inner and outer two blade plates 1, 1 'having the same dimensions and the same shape are overlapped while being shifted in the length direction. The total number of blades 2 and 2 ′ can be doubled as compared with the conventional one without changing the shape and processing dimensions, and the two inner and outer blade plates 1 and 1 ′ are cut and raised, and the groove 4 ′ of the protrusion 3 is formed. Since the outer blade 1 'is stretched in the circumferential direction, the difference in the circumferential length due to the difference in the plate thickness of the radii of both the blades 1, 1' Is absorbed, and the pitch of the blades 2 and 2 ′ is maintained at an equal interval ((P / 2) pitch). As a result, the static pressure capability of the impeller 10 is enhanced.
[0033]
Further, in the present invention, the portion protruding from the groove 4 'of the cut and raised projection 3 is bent and the inner and outer blade plates 1 and 1' are connected, so that the impeller 10 is secured with high rigidity and its rotational breaking strength is increased. Therefore, the permissible rotational speed of the impeller 10 can be increased to improve its performance. Furthermore, in the present invention, both ends of the impeller body 6 in the axial direction are subjected to end processing by curl molding, and the end portions of the two inner and outer blades 1 and 1 'which are double-rolled into a cylindrical shape are joined and integrated. Therefore, the conventionally required fixing ring is not required, the number of parts is reduced, and the impeller 10 can be reduced in weight and cost.
[0034]
In the above embodiment, the impeller body 6 is obtained by superposing the two inner and outer blades 1 and 1 ′ having the same dimensions and the same shape in the longitudinal direction and overlapping them in a cylindrical shape. However, as shown in FIG. 10, one long blade plate 1 is shifted by a predetermined pitch ((P / 2) pitch) and continuously wound twice to constitute an impeller body. However, this method has the advantage of facilitating the automation of manufacturing.
[0035]
【The invention's effect】
As apparent from the above description, according to the invention of claim 1 Symbol mounting, double-wrap the two vanes separate the same size and the same shape formed by projecting a plurality of blades equally spaced In addition, according to the second aspect of the present invention, the number of blades is doubled without changing the shape or processing size of the blade plate by continuously double-winding one blade plate. In addition, the overlapped inner and outer blades are securely positioned by cutting and raising the fittings into the grooves, and the circumferential extension of the outer blades makes the difference between the thicknesses of the radii of both blades Since the difference in the circumferential length due to is absorbed and the pitch of the blades is kept at an equal interval, the effect of increasing the static pressure capability of the impeller can be obtained.
[Brief description of the drawings]
FIG. 1 is a partial plan view of a blade.
FIG. 2 is a partial side view of the vane (a view in the direction of arrow A in FIG. 1).
FIG. 3 is a front view of the vane (a view in the direction of arrow B in FIG. 1).
FIG. 4 is a partial perspective view of two inner and outer blades.
FIG. 5 is a partial side sectional view showing a state in which two inner and outer blades are superposed.
FIG. 6 is a perspective view showing a state where two inner and outer blades are double-wound.
FIG. 7 is a perspective view of an impeller body.
FIG. 8 is a longitudinal sectional view of an impeller for a sirocco fan according to the present invention.
9 is an enlarged detail view of a part C in FIG. 8. FIG.
FIG. 10 is an explanatory view showing another manufacturing method of an impeller for a sirocco fan according to the present invention.
[Explanation of symbols]
1, 1 'blade plate 2, 2' blade 3, 3 'cut and raised projection 4, 4' groove 5, 5 'notch groove 6 impeller body 7 back plate 8 boss 9 fixing bolt 10 impeller for sirocco fan

Claims (2)

In a sirocco fan impeller comprising a cylindrical impeller body by double winding an impeller formed by projecting a plurality of blades at equal intervals by cutting and raising a belt-shaped metal plate ,
A plurality of cut-and-raised protrusions and grooves are alternately formed in the length direction at both ends in the width direction of two separate blades of the same size and the same shape , and the two blades are cut and raised on the inside. sirocco fan of so as to fit into the groove and wound doubly cylindrical constitute the impeller body, characterized in that projecting from a plurality of blades at equal intervals on the inner periphery of the impeller body Impeller. In a sirocco fan impeller comprising a cylindrical impeller body by double winding an impeller formed by projecting a plurality of blades at equal intervals by cutting and raising a belt-shaped metal plate ,
A plurality of cut-and-raised protrusions and grooves are alternately formed in the longitudinal direction at both ends in the width direction of one blade, and the one blade is fitted with the outer-cut and raised protrusions in the outer groove. continuously double winding to constitute the impeller body, features and be Resid Rocco fan impeller that projecting a plurality of blades at equal intervals on the inner periphery of the impeller body.

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