JPH0740716Y2 - Centrifugal blower impeller - Google Patents

Description

TECHNICAL FIELD The present invention relates to an impeller of a centrifugal blower mainly used for air conditioning and ventilation.

2. Description of the Related Art Conventionally, as shown in FIG. 4, an impeller of a centrifugal blower of this type is folded back at both ends 11a where the curvature ends so as to support the central part of the chord length of the blade plate 11, and a main plate (not shown). ) And the side plate 3 are further folded back at the folding portions 11b and 11c to form a portion to be crimped. The outer peripheral side end of the vane plate 11 has an arcuate shape in order to disperse the stress on the strength because the folded portions 11a and 11b and the curvature of the vane plate 11 overlap with each other and stress is applied when rotating. The notch 11d was provided.

Problems to be Solved by the Invention In such a conventional configuration, although power is transmitted to the air by the vane plate 11, air leakage occurs due to the cutout portion 11d at the outermost peripheral portion, which is the air outlet side, and is substantially reduced. Has the same characteristics as an impeller with a small effective diameter. Also, the notch
11d had a problem that since the radius R of the circular arc was small, variation in molding was likely to occur and it was not sufficient for the purpose of stress distribution.

The present invention solves such a problem, and provides an impeller of a centrifugal blower composed of a blade plate that is easy to process, secures strength, and can exhibit characteristics matching the outer diameter of the impeller. It is intended.

Means for Solving the Problem In order to solve this problem, the present invention provides a plurality of vanes standing on the outer peripheral edge of a disc-shaped main plate, and the ring-shaped side plate is opposed to the main recording main plate. And sandwiching the outer periphery of the main plate and the side plate, the sandwiching portion sandwiches the end portion of the vane plate for tightening and tightening, and the end portion is an L-shaped folded back portion on the outer peripheral side. On the circumferential side, an impeller of a centrifugal blower having a Z-shaped three-fold folded shape is used.

Action With this configuration, the outer peripheral portions at both ends of the vane plate, on which the twisting force, the tensile force, and the compressive force applied to the vane plate during rotation are concentrated, have a single folded shape and have a curvature up to the end portions.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. As shown in the figure, the vane plate 1 having a curvature is fixed at its both ends by a disc-shaped main plate 2 and a ring-shaped side plate 3, and is arranged on the outer edge of the main plate 2 at equal intervals. A boss portion 4 transmitting a rotational force is fixed to the central portion of the main plate 2. As shown in FIG. 2, the blade 1 is a blade 1
The folds are folded back at both ends 1a where the curvature ends, and further folded back to make a portion crimped by the main plate 2 and the side plates 3.
Wrapped at 1b and 1c. Bending is not performed at the outer edge portion 1d where the folded-back portions 1a and 1b are close to each other, and only one bend is made at the folded-back portion 1c for caulking. The blade plate 1 is designed to fix the blade plate 1 by fitting the end portion 1e bent at the folded portion 1c into the groove portion 3a of the side plate 3 and bending the caulked portion 3b of the side plate 3. The main plate 2 side has the same structure.

In the above configuration, when the entire impeller rotates, the air sucked from the inside of the ring-shaped side plate 3 is powered by the blade plate 1 and discharged in the centrifugal direction. At this time, since the vane plate 1 has a curved portion up to both ends, the power that can be given to the air can be transmitted without loss as compared with the conventional case.
FIG. 3 shows an example of characteristics of the impeller of the present invention. It can be seen that the product of the present invention outperforms the conventional product in both static pressure and total pressure efficiency within the usable range.

Further, the vane plate 1 can be molded with almost no residual stress at the outer edge portion 1d, does not change with time, and can be operated at a higher rotation speed than the conventional one, and a high static pressure can be obtained.

Effect of the Invention As is apparent from the above description of the embodiments, according to the present invention, the residual strain at the time of molding is reduced by forming the outer peripheral side of both end portions of the vane plate into a single folded back shape. ,
As a result, the strength against stress concentration during rotation is improved, the effective area of the impeller is increased, and the characteristics are improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a vane plate joint portion of a centrifugal blower according to an embodiment of the present invention, and FIG. 2 is a sectional view of an impeller of the centrifugal blower.
FIG. 3 is a performance comparison diagram between the same impeller and a conventional impeller,
FIG. 1 is a perspective view of a blade plate joint portion of an impeller of a conventional centrifugal blower. 1 ... vane plate, 1a, 1b, 1c ... folded part, 1d ... outer edge part, 1e ... end part, 2 ... main plate, 3 ... side plate, 3a ... groove part.

Claims (1)

[Scope of utility model registration request] 1. A plurality of vanes are erected on the outer peripheral edge of a disc-shaped main plate, and a ring-shaped side plate is sandwiched between the main plate and the vane plate, and the sandwiching portion is provided between the main plate and the side plate. Centrifugal with a folded groove formed on the outer circumference, sandwiching and tightening the end of the blade plate, the end being an L-shaped single turn on the outer peripheral side and a Z-shaped three-fold shape on the inner peripheral side. Blower impeller.