RU2426012C2 - Fan impeller - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed impeller of fan or axial-flow blower with vaned disk comprises vane root and vane working side.Two clamp blocks are provided for fitting vanes in place. Note here that both clamp shoes of clamp blocks are arranged on both sides of bearing disk and screwed thereto and feature similar shape to allow their interchangeability. Note that each clamp block has its radially outer edge transforming into skirt oriented outward. Besides, skirts form hub ring on impeller every side to make flow guide.

EFFECT: impeller reliability in operating conditions.

9 cl, 2 dwg

Description

The invention relates to the field of axial fans or axial air blowers. Such fans are used, for example, in road tunnels. Such an axial fan usually consists of a rotor and a housing with an output guide vane. The rotor contains a number of blades, which are located on the hub of the impeller. Each blade consists of the working side of the blade and the legs of the blade.

The blade transfers considerable efforts to the hub, which are first determined by the discharge work of the impeller, but mainly by the centrifugal force of the rotating masses. The blade can consist of various materials and can be manufactured in various ways. In this case, we are talking essentially about cast vanes, which together with a hub of identical clamping blocks, a bearing disk and a hub shaft form an impeller.

Impellers are known which are constructed as follows: the impeller has a circular bearing disk. The blades are clamped on the carrier disk in stamped half-holes. At rest, the blades can be rotated so that certain blade angles can be set.

Impellers of the aforementioned type are produced in large quantities. With strong international competition and correspondingly strong pressure from prices, they are striving for solutions that are economical but reliable at the same time. When operating axial fans, things can go as far as the extreme operating conditions that must be maintained by such fans without a failure of the function. A special extreme case occurs, for example, when a fire occurs in a forced-ventilated tunnel. According to the prescribed safety rules, the fan with all its components must still remain fully operational at extremely high temperatures, for example 400 ° C, for a long period of time.

The basis of the invention is to provide an impeller that can be used for an axial fan or an axial air blower that meets all the requirements for strength and reliability in operation and which is economical to manufacture.

This task according to the invention is solved by an impeller for an axial fan or an axial air blower with a carrier disk, with several blades, which respectively comprise a blade leg and a working side of the blade, for which each pair of clamping blocks is provided for inserting each blade, both clamping blocks of each pair of clamping the pads are located on both sides of the carrier disk and screwed to it, and the clamping pads of each pair of clamping pads are made identical in terms of their shape so that they interchange enyaemy, wherein each clamping jaw moves into its radially outer region to the apron, which is oriented outwards and which together form the apron on each side of the impeller extending along the perimeter of the hub ring as a flux guide.

Accordingly, such an impeller contains the following details:

- carrier disk

- several blades with the leg of the blade and the working side of the blade,

- a pair of clamping pads for inserting the legs of the blades of each blade, and

- both clamping pads of each pair of clamping pads are located on both sides of the carrier disk and screwed to it,

- all clamping pads are identical with respect to their shape, in any case, so much that they are interchangeable.

The carrier disk as well as the blade leg are located like a sandwich between two clamping blocks of one pair of clamping blocks.

The identity of the clamping blocks has the following advantages:

- in comparison with conventional impellers, the individual parts are significantly simplified with respect to their shape. Clamping pads are produced as stamped parts in large quantities, so that production can be streamlined,

- if all the clamping blocks are identical to each other, there is no confusion during installation,

- storage at the warehouse is simplified,

- the same sample of clamping blocks can also be used for different values of the diameter of the impeller.

Thus, for example, it is possible to create a row of impellers according to the invention by using identical clamping blocks in the next row of hub diameters (normalized number row R20) (see table).

Hub Diameter D _N Outside Diameter D _A min D _A max 630 900 1600 710 1000 1700 800 1120 1800 900 1250 1900 1000 1400 2000 1120 1500 2100 1250 1600 2250 1400 1800 2400

For the aforementioned, as an example, a series of hub diameters with related impeller dimensions, the same clamping blocks can be used respectively. At the same time, great chances are obtained for mass rationalization.

The invention is explained in more detail with reference to the drawings. They, in particular, presented the following:

figure 1 - part of the impeller for an axial fan in axial section, however, without a blade,

figure 2 is a top view when viewed in the direction A of figure 1.

1, in particular, the carrier disk 1 can be seen. In this case, it is round. Without rotation, it is connected to the hub 2 of the drive shaft (see central screws 3 and washer 4).

There is one clamping block 5.1 and 5.2 on each side of the carrier disk. Both pads have an absolutely identical shape. They, like a sandwich, enclose a radially outer region of the carrier disk 1. The carrier disk 1, the terminal block 5.1 and the terminal block 5.2 are rigidly connected to each other by means of a through bolt 6, as well as by means of two intermediate parts 7.1 and 7.2 and the terminal block 7.3 for centrifugal transmission forces on the carrier disk.

The best solution is to have all the clamping blocks absolutely identical in shape, however, deviations are possible. Thus, only clamping blocks of one pair of clamping blocks can be made identical to each other.

Both clamping blocks 5.1 and 5.2 form, with each other, a receptacle 8 for mounting a leg of a blade not shown here. During installation, the blade leg is inserted into the receiving socket 8 while the through bolt 6 and the clamping screws 10 are not yet tightened. In this case, you can rotate the blade around its own longitudinal axis, than you can set the angle of the blade.

As you can see, each clamping block 5.1, 5.2 in its radially external region is bent outward and forms an apron 5.1.1 and, accordingly, 5.2.1. The apron extends approximately perpendicular to the plane of the carrier disk, so that the aprons of all the clamping parts on each side form a hub ring extending around the periphery to direct the flow.

The front cowl is visible 9. It is mounted on one side of the carrier disk 1, namely, so that it forms a transition flush with the apron 5.1.1.

In Fig.2, you can also see the carrier disk 1, namely its outer perimeter 1.1. It is understood that the term "carrier disk" must be understood as any design that could take on its function. Thus, a spoke wheel would also be possible.

Further, you can see the through bolts 6 with the distance elements 7.1 and 7.2 and the clamping sleeves 7.3.

You can see the clamping pads 5.2, which are located in figure 1 on the right side of the carrier disk 1. The clamping pads have bends 5.2.3 and 5.2.4. In this case, respectively, the bend 5.2.3 of one clamping pad overlaps the bending 5.2.4 of the adjacent clamping pad. In the area of this overlap, the clamping blocks have elongated holes. They serve to receive clamping screws 10, which are located radially outside the outer perimeter 1.1 of the carrier disk 1 and which connect to each other both opposite clamping blocks 5.1 and 5.2 of one pair of clamping blocks. The two clamping screws 10 located further outside the clamping force produce a clamping force to tighten the blade legs. Naturally, when mounting individual blades, the clamping screws 10 must also be tightened in turn.

The overlapping of adjacent clamping blocks takes place not only in the area of the bends 5.2.3 and 5.2.4, but also in the radially extreme region of the aprons 5.2.1.

Clamping blocks 5.1 and 5.2 due to their identical design can be used on impellers of different diameters. In this case, only the bearing disk 1 and, if necessary, also the shaft 2 should be changed in diameter. It is important that the clamping blocks 5.1 and 5.2 always remain identical.

Clamping blocks 5.1 and 5.2 are preferably stamped parts, castings or forgings, as well as vanes.

List of basic designations

1. Carrier disc

1.1 External perimeter of the carrier disk

2. Drive shaft hub

3. Center screws

4. Washers

5.1. Clamping pads

5.2. Clamping pads

5.1.1. Apron

5.2.1. Apron

5.2.3. Bend

5.2.4. Bend

6. Through bolt

7.1. Distance element

7.2. Distance element

8. Receiving socket

9. Front fairing

10. Clamping screws

Claims (9)

1. The impeller for an axial fan or axial air blower with a carrier disk (1), with several blades, which respectively contain the blade leg and the working side of the blade, and a pair of clamping blocks (5.1, 5.2) are provided for inserting each blade, both clamping blocks (5.1, 5.2) of each pair of clamping blocks are located on both sides of the bearing disk (1) and screwed to it, and the clamping blocks (5.1, 5.2) of each pair of clamping blocks are made identical in terms of their shape so that they are interchangeable, and each I clamping block (5.1, 5.2) passes in its radially external area into an apron (5.1.1, 5.2.1), which is oriented outward, and moreover, the aprons (5.1.1; 5.2.1) together form on each side of the impeller passing along the perimeter of the hub ring as a flow guide. 2. The impeller according to claim 1, wherein all the clamping blocks (5.1, 5.2) are made identical. 3. The impeller according to claim 1, characterized in that the legs of the blades have a circular cross section when viewed across the longitudinal axis of the blade, and the receptacle for an individual leg of the blade corresponds in shape to the leg of the blade. 4. The impeller according to claim 1, characterized in that the adjacent clamping blocks (5.1, 5.1; 5.2, 5.2) overlap each other. 5. The impeller according to claim 1, characterized in that the clamping pads (5.1, 5.2) have elongated holes, and the supporting disk has round sockets for passing through bolts (6) through them. 6. The impeller according to claim 5, characterized in that the elongated holes are provided in the area of mutual overlap of the blades (5.1, 5.1; 5.2, 5.2). 7. The impeller according to claim 1, characterized in that the clamping screws (10) are provided outside the perimeter (1.1) of the carrier disk to tighten the blades between the clamping blocks (5.1, 5.2) lying opposite each other and to tighten the clamping blocks from opposite sides. 8. The impeller according to claim 1, characterized in that the clamping blocks (5.1, 5.2) are forgings, castings or stamped parts. 9. The impeller according to any one of claims 1 to 8, characterized in that it can be made with different diameters of the hubs and different external diameters, but with identical clamping blocks (5.1, 5.2) to enable the creation of a constructive row of impellers.

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