The invention is explained below by way of example with reference to the drawing.
FIG. 1 shows a diagrammatic view of an impeller disk with only one blade for a propeller blower according to the (; invention.
FIG. 2 shows a diagrammatic view of the blade shown in FIG. 1, detached from the impeller disk.
FIG. 3 shows the impeller disk with indentations and a blade.
FIG. 4 shows a sectional view according to A-B of FIG. 2.
FIG. 5 shows a diagrammatic view of another propeller blower according to the invention.
According to the FIGS. 1 to 3, the impeller disk 2 is driven rotary around the axis of rotation 3. The direction of rotation is indicated by the arrow 5.
For the sake of a better overview only one blade 1 is shown in the FIGS. 1 to 3. In the practical implementation usually several blades 1, spaced uniformly of not uniformly, also in different sizes, will be attached to the impeller disk.
The blade 1 has substantially the shape of an oyster shell and is integrally connected with the impeller disk 2, or incorporated or glued into it. They can be formed by injected or moulded parts; it is substantial that the blade 1 and the impeller disk 2 have entered into a so-called penetration such that a dedendum line 6 is created, which merges outside of the penetration into the discharge edge of the blade 1. The edge opposed to the dedendum line 6 is the blade entrance edge 22, at which the medium flows in. It can be seen in FIG. 1 by the arrows 30 that the blade entrance edge extends up to the outer area. In the area 20 the blade 1 is oriented radially, while it is axially oriented in the area 21.
FIG. 2 again illustrates the special shape of the blade 1, wherein in FIG. 4 the section A-B from FIG. 2 is shown. The angle 4 shown in FIG. 4 indicates the inflow angle between the vector 5 of the rotary velocity and the edge direction of the blade 1.
In FIG. 3 an indentation 4 in the impeller disk 2 can be recognised before the dedendum line 6, which contributes to the increase of the radial flow. With the proposed propeller blower also water and air crafts can be driven.
A propeller according to the invention is proposed in FIG. 5, which also at its outer edge still sucks in the conveyed medium such as water or air. An especially advantageous arrangement of this new propeller regarding the sucking in of air or other liquids from a space under differential pressure is obtained, when the location of the outer edges or propeller blades 1, where the sucking-in turns into the outflow, is situated according to FIG. 5 exactly inside of a hole in the plane of the outer wall 10 of the space the medium is to be sucked off from. The plane of the outer wall is then, according to FIG. 5, near the outer edge of the propeller blades 1. Arrows 30 indicate the flow direction. It is additionally illustrated in FIG. 5 that L the edges of the propeller blades 1 can be rounded such that the propeller blades do not have any corners, as shown in the bottom part of FIG. 2.
The feature of a conically spread outflow, which can still be somewhat extended by suitable shaping, enables blowing of air through cooling pipes assembled in cooling packs, without the necessity of any limiting plates at the entrance or discharge edge. Thus, sucking off media from a room can be enabled, wherein the propeller is situated on the suction side inside the room and the opening is enclosed by a slotted pipe, in order to reduce the noise generated by Karman vortexes.
Patent Application
20080050239
