JPS6035199A - Impeller of blower - Google Patents

Abstract

PURPOSE:To improve blast efficiency through prevention of the exfoliation of an air flow, by a method wherein a number of about semispherical recesses are formed in an entire surface or a part of a surface which makes contact with an air flow generated through the rotation of an impeller. CONSTITUTION:A number of about semispherical recesses 15 are repsetively formed in the face of the blade 11 side of a front shroude 9, the face of the blade 11 side of a rear shroude 10, the surface of the blade 11, and the surface of an input guide 12. This causes the generation of a negative pressure occasioned by a decrease in an amount of the air at the inside of the about semispherical recesses 15 even if an air flow is accelerated to a high speed and is going to be exfoliated from the surface of an impeller. This causes prevention of the exfoliation of an air flow.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an impeller for an air blower with improved air blowing efficiency.

Structure of a conventional example and its problems An example of a conventional blower is shown in FIG. 1 is the impeller, 2
is the casing that covers impeller 1, 3 is impeller 1
This is the motor that drives the.

The impeller 1 includes three members: a front shroud; Consisting of a blade 6 and a rear shroud 6, the blade 6 is connected to the front shroud 4 and the rear shroud 6.
The impeller 1 is formed by being swaged together.

7 is the force 2 of blade 6 This is the bottom part. Further, 8 is an entrance guide.

The members 4, 6° 6 and the inlet guide 8 that form the impeller 1 have smooth surfaces. Now, if we consider the airflow inside the impeller driven by the motor 3, we can see that the airflow is It flows in contact with the inner surface of the front shroud 4, both surfaces of the blade 6, the blade surface of the rear shroud 6, and the surface of the inlet guide 8. When impeller 1 rotates at high speed, the speed of airflow also increases, resulting in slight changes in conditions (changes in flow rate 2 rotation speed, etc.)
This causes peeling from each contact surface inside the impeller. This peeling was one of the factors that significantly reduced the blowing efficiency of the blower.

Purpose of the Invention The present invention provides an impeller for a blower with high air blowing efficiency by improving the surface condition of the parts constituting the impeller in order to eliminate such causes of deterioration in the efficiency of the blower. be.

Structure 3 of the invention:--1 The impeller of the blower of the present invention has a large number of four substantially hemispherical parts on the entire surface or a part of the surface that comes into contact with the airflow generated by the rotation of the impeller, and the dimensions of each part of the impeller are as follows: The condition remains the same as before, but only the condition of the surface in contact with the airflow is changed, and when the airflow generated by the rotation of the impeller tries to separate from the impeller surface, the approximately hemispherical depression provided on the impeller surface becomes negative pressure, and the negative pressure increases. The pressure acts to attract the airflow, which eliminates separation of the airflow and increases the efficiency of air blowing.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. The overall configuration is the same as the conventional example shown in Figure 1,
FIGS. 2 and 3 show enlarged views of essential parts of the impeller of the present invention. In the figure, 9 is a front shroud, 10 is a rear shroud, 11 is a grade, 12 is an entrance guide,
13 is a hole for the motor shaft. The front shroud 9, the blades 11, and the rear shroud 1o are caulked together to form an impeller 16. Reference numeral 14 indicates a caulking portion provided in Grade 11 JP-A-Sho GO-35199 (2). A large number of approximately hemispherical recesses 16 are provided on the surface of the front shroud 9 on the blade 11 side, on the surface of the rear shroud 10 on the blade 11 side, on both sides of the grade 11, and on the surface of the input guide 12.

The present invention has the above-described configuration, and when the impeller 16 is driven by an electric motor, the airflow flows through the substantially hemispherical recess 1 described above.
However, even if the airflow becomes high-speed and attempts to cause separation from the impeller surface (as indicated by the dotted line arrow in Figure 4), the amount of air inside the approximately hemispherical recess 15 at the separation location will decrease. As a result, the inside of the substantially hemispherical four parts 16 becomes negative pressure, which has the effect of pulling back the airflow that is about to cause separation, and as a result, the separation is reduced (as indicated by the solid line arrow in FIG. 4). Eliminating separation allows the airflow inside the impeller to flow smoothly, improving air blowing efficiency.

Although the above-described embodiments of the present invention are examples in which the present invention is applied to a centrifugal fan, it goes without saying that the present invention can be applied to impellers of various types of blowers such as axial fans and multi-blade fans to achieve the same effect.

Effects of the Invention As is clear from the above embodiments, the impeller of the blower of the present invention is provided with a large number of approximately hemispherical recesses on the surface that is in contact with the airflow generated by its rotation, so that the airflow is prevented during high speed rotation of the impeller. Even if an attempt is made to cause separation from the surface inside the impeller, the four substantially hemispherical parts provided on the surface create negative pressure and act to pull back the separated airflow.Thus, if the impeller of the present invention is used, The internal peeling phenomenon is greatly reduced, which has the effect of providing a highly efficient blower.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the main parts of a conventional electric blower, FIG. 2 is a side sectional view showing an embodiment of the impeller according to the present invention, and FIG. 3 is a sectional view of the main parts of the same impeller as seen from the front shroud side. Figure 4 is a diagram showing the relationship between the approximately hemispherical hole provided in the impeller and airflow.
Figure 2, Figure 3, Figure 15? (≦Door-■Meg2ヱ≦”; l, la5 Fig. 4

Claims (1)

[Claims] The entire surface that comes into contact with the airflow generated by rotation is the impeller of a blower, which has a number of four roughly hemispherical parts on a part of it.