JPS60560B2 - Blower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air blower, and more specifically, it is suitable for application to a multi-stage air blower having an elastic casing.

Multi-stage blowers are effective when used in large vacuum cleaners or devices that require high pressure. Air blowers are used for large vacuum cleaners and devices that require high pressure.
A multi-stage blower is used, and the casing of this multi-stage blower has recently been made of an elastic thin plate molded product for the purpose of improving precision and productivity.

The above-mentioned elastic casing is tightened and fixed to prevent air leakage from the seam, but a collar is inserted into the tightening screw portion in order to obtain sufficient binding force.

However, this method of employing a collar requires many parts and is difficult to disassemble and reassemble, and it is difficult to bend the elastic casing evenly over the entire circumference, so it is necessary to sufficiently improve the collar accuracy in order to seal the entire circumference. There were certain drawbacks. The present invention focuses on the above-mentioned disadvantages and relates to an invention of a tightening means for an elastic casing that has a simple structure and can easily obtain a sealing effect. Embodiments of the present invention will be described below using the drawings as a blower of a large vacuum cleaner.

In FIG. 1, a blower 1 is built into a vacuum cleaner, and when a motor 2 rotates, a motor pulley 3,
It is operated via a V-belt 4 and a blower pulley 5.

Air, dust, etc. are sucked through the suction port 7 by the suction force of the blower and filtered through the filter 6. Further, the structure of the blower according to the present invention is shown in FIG. In FIG. 2, the rotation of the blower pulley 5 causes the fan 9 to rotate at high speed through the blower shaft 8, thereby compressing and moving air as indicated by the arrow in FIG. In such a multi-stage blower, the casing that forms the outer shell is made of an elastic molded product such as a thin steel plate, and the degree of airtightness of each chamber is determined by the penetration hole drilled in the outer periphery flange 13 of the casing 10. A tightening screw 12 is passed through the hole, and when the tightening screw 12 is tightened, the casing 10 is bent, and the casing 10 is exposed by the tight contact. The flange portion 13 of the casing located at this position cannot obtain sufficient deflection.

Therefore, conventionally, as shown in FIG. 5, a collar 14 is attached to the tightening screw 12 so that the collar 13 can be sufficiently attached. However, in this method, although sufficient adhesion can be obtained at the collar 14, the degree of adhesion decreases as the distance from the collar 14 increases.

Therefore, in order to obtain adhesion over the entire circumference, color 1
4 had to be improved in dimensional accuracy in the length direction, and the price was also high. Further, the number of collars 14 is large (for example, 24 collars are required for a four-stage blower with eight cotton screws), which poses a problem in disassembly and assembly. The present invention provides a sixth method as an alternative to attaching means using a subordinate collar.
A constant piece 11 as shown in the figure is attached near a cotton screw 12.

If this constant piece 11 is used and assembled as shown in FIG. 1, only three constant pieces are required for a four-stage blower, and ease of disassembly and assembly is greatly improved. The diameter of the constant piece 11 should be placed as close as possible to the tightening screw 12, and according to various experiments, the best position for attaching the constant piece 11 is inside the vertical screw 12, as shown in Figure 2. Further, when the constant piece 11 of the present invention is used, as shown in FIG. 3, the adhesive force is applied to the entire circumference of the flange 13 of the casing 10, and the degree of adhesion that can best withstand high pressure can be obtained. .

Since the blower according to the present invention has the above-described operational structure, it is possible to improve ease of disassembly and assembly by reducing the number of parts, and to sufficiently satisfy the required performance at a low cost, which has a great effect on the blower.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an example in which the blower according to the present invention is used in a large vacuum cleaner, Fig. 2 is a front cross-sectional view of the blower according to the present invention, and Fig. 3 is a cross-sectional view taken along the line AA in Fig. 2. Figure 4 showing the main parts of
The figures are a sectional view taken along the line BB in FIG. 3, FIG. 5 is an enlarged sectional view of main parts showing a conventional embodiment, and FIG. 6 is a perspective external view of main parts used in the blower according to the present invention. 1... blower, 9... fan, 10... blower case,
11... Constant piece, 12... Fixing screw. Younger brother's figure 2 figure 3 figure younger brother's figure 4 figure 5 figure 5

Claims (1)

[Scope of Claims] 1. A shaft rotated by a prime mover, a plurality of impellers fixed to the shaft, a molded elastic fan casing unit enclosing each impeller, and each fan casing. A blower comprising a bent part formed on a unit and in airtight contact with an adjacent fan casing, and a tightening means for tightening each fan casing unit on the outer periphery of the bent part, the fan casing unit's outer periphery being A blower characterized in that a tightening screw is passed through a through hole between the parts, and a cylindrical constant piece is interposed near the tightening screw to tighten the fan casing unit. 2. The blower according to claim 1, wherein the cylindrical constant piece has a diameter such that it comes into contact with the tightening screw.