JPH0450903Y2 - - Google Patents

Description

[Detailed explanation of the idea]

a. Industrial Application Field The present invention relates to a cyclone dust collector used in various industrial fields. b. Conventional technology and problems to be solved Conventionally, the dust collection efficiency of cyclone dust collectors was approximately 90
~95% was the limit. One reason for this is that uncollected particles in the inflowing gas are entrained in the clean airflow after dust collection and are discharged. FIG. 3 illustrates this state. In the figure, solid arrows indicate dust-containing airflow, and broken arrows indicate clean airflow. The dust-containing airflow enters the cyclone through the inlet duct a, travels straight, rotates along the inner wall of the outer cylinder b of the cyclone, is removed from dust, and is then discharged outside the machine from the inner cylinder c as a clean airflow. At this time, a part of the dust-containing airflow tends to change direction inward after colliding with the inner wall of the outer cylinder b, be accompanied by the clean airflow entering the inner cylinder c, and be discharged from the inner cylinder c. Therefore, as illustrated in Fig. 3, we found that by providing an internal and external flow separation plate d in a specific area of the dust collector, it was possible to eliminate the drawback that a part of the dust-containing airflow was entrained in the clean airflow. We have arrived at this idea. c. Means for Solving the Problems The gist of the present invention is to set an imaginary line that is perpendicular to the inflow direction of the dust-containing airflow flowing into the outer cylinder from the inlet duct and passes through the center of the dust collector as a base line, and to draw air from the base line into the machine. An internal/external flow separation plate is provided downward from the top surface of the machine in an area extending approximately 90° toward the plane, and the vertical dimension of the internal/external flow separation plate is equal to or larger than the vertical dimension of the inlet duct and of the outer cylinder. There is a cyclone dust collector in which the vertical dimension of the cylindrical part is set to less than or equal to the vertical dimension. What is shown in the drawing is an embodiment of the invention, in which a virtual line 3 that is approximately orthogonal to the inflow direction of the dust-containing gas g and that passes through the center 2 of the dust collector 1 is used as a base line, and a line extending from the base line 3 toward the inside of the machine is approximately An internal/external flow separating plate 7 is provided between the outer cylinder 4 and the inner cylinder 5 in a region extending over 90 degrees, extending downward from the upper surface 6 of the machine. In the figure,
8 is the inlet duct of the cyclone dust collector, 9 is the outer cylinder 4
This is the bottom outlet. Now, the dust-containing airflow that has flowed into the outer cylinder 4 from the inlet duct 8 hits the inner wall of the outer cylinder 4, as shown in Fig. 3, and a part of it changes direction inward. The direction of the flow is corrected by the inner and outer flow separation plate 7, and the flow is circulated along the inner wall of the outer cylinder 4, during which gas and solids are separated,
Substantially only clean gas is discharged from the inner cylinder 5 to the outside of the machine, and separated solids are discharged from the outlet 9, thus achieving efficient dust collection. In the present invention, it is preferable that the arrangement of the internal and external flow separation plates 7 be within the following numerical range, as shown in FIGS. 4 and 5. That is, in FIG. 4, when the height of the cylindrical part of the outer cylinder 4 is _h1 , the height of the internal and external flow separation plate 7 is _h2 , and the height of the inlet duct is _h3 , h ₂ = h ₃ +
α×(h ₁ −h ₃ ), [however, 1≧α≧0]. When α<0, there is no separation plate in the part shorter than the height of the inlet duct, so the effect is lost in that part, and the dust collection efficiency cannot be significantly improved as a whole. In addition, when α>1, the improvement in dust collection efficiency is small;
On the contrary, pressure loss increases significantly, which is not preferable. In addition, in FIG. 5, the inner diameter of the outer cylinder 4 is r ₁ , the radius from the center to the inner and outer flow separation plate 7 is r ₂ ,
When the inner diameter of the inner cylinder 5 is r ₃ and the central angle occupied by the internal and external flow separation plate 7 is θ, (1) r ₂ = r ₃ + β × (r ₁ − r ₃ ) [however, 0.5≦β≦1.0] (2) The front end of the separation plate 7 is at the θ=0 position, and the rear end is at the θ=0 position.
The position should be 60°≦θ≦90°. In terms of efficiency, it is most preferable to provide the separation plate 7 at the boundary between the inflowing airflow and the airflow rotating inside the cyclone. The region is 0.5≦β≦1.0, and a suitable location within this region is selected by experiment. Outside this range, the dust collection efficiency decreases accordingly. d Example When θ = 90°, α = 0.7, β = 0.8, cement raw powder was collected from the air stream using the cyclone dust collector shown in Figures 1 and 2, and the following results were obtained. Ta.

[Table] e Effects According to the present invention, as seen in the table above, dust collection efficiency can be increased without causing almost any pressure loss.

[Brief explanation of the drawing]

Figure 1 is an elevational view of the cyclone dust collector according to the present invention, Figure 2 is a sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view taken along line A-A in Figure 1.
The figure shows the flow of dust-containing airflow and clean airflow inside the cyclone, the same figure being the conventional one, and the same figure being the one according to the present invention. FIGS. 4 and 5 are diagrams showing the dimensions of each part of the cyclone dust collector of the present invention, centering on the internal and external flow separators. 1... cyclone dust collector, 3... baseline, 4...
Outer cylinder, 5... Inner cylinder, 7... Inner/outside flow separation plate, h ₁ ...
Height of the cylindrical part of the outer cylinder (vertical dimension), h ₂ ... Height of the inner and outer flow separation plate (vertical dimension), h ₃ ... Height of the inlet duct (vertical dimension).

Claims (1)

[Scope of utility model registration request] An imaginary line that is perpendicular to the inflow direction of the dust-containing airflow flowing into the outer cylinder from the inlet duct and passes through the center of the dust collector is the base line, and approximately 90 degrees from the base line toward the inside of the machine.
An internal and external flow separation plate is provided in a region extending downward from the top surface of the machine, and the vertical dimension of the internal and external flow separation plate is equal to or larger than the vertical dimension of the inlet duct, and the vertical dimension of the internal and external flow separation plate is larger than or equal to the vertical dimension of the cylindrical portion of the outer cylinder. A cyclone dust collector that is set to less than the directional dimension.