WO1999063231A1

WO1999063231A1 - Safety jacket-lining for a housing embodying a rotating impeller

Info

Publication number: WO1999063231A1
Application number: PCT/FI1999/000474
Authority: WO
Inventors: Jarmo Kalevi ALAMÄKI; Rauno Sinersalmi; Seppo Jyrkinen
Original assignee: Alamaeki Jarmo Kalevi; Rauno Sinersalmi; Seppo Jyrkinen
Priority date: 1998-06-01
Filing date: 1999-06-01
Publication date: 1999-12-09
Also published as: FI3651U1; AU4619199A; FIU980276U0

Abstract

The present invention relates to a safety structure comprising a protective sheath, said structure being intended for installation in connection with the peripheral structure (9) of a housing (1) for a device like a fan blower or the like comprising a rotating rotor (2). The arrangement comprises a layered protective sheath which is integrated in especially said peripheral structure. The present invention also relates to a housing (1) safety structure for a device comprising rotating rotor (2) such as a fan blower or the like. Here a layered protective sheath (11) is connected with the peripheral structure (9) of said housing (1), said sheath being integrated into said peripheral structure.

Description

Safety jacket-lining for a housing embodying a rotating impeller

The present invention relates to a safety arrangement including a protecting sheath, said arrangement being intended for installation into connection with the peripheral structure of the housing of a device comprising a rotating rotor, such as a fan blower or the like . The invention also relates to the peripheral structure of the housing for a device comprising a rotating rotor, such as a fan blower or the like.

Traditionally, either cast or sheet structure housings are used in devices comprising a rotating rotor, such as centrifugal fan blowers and the like. The pressure and/or the medium stream of a fan blower or the like is generated within said housing by means of a rotating blower or compressor wheel or the like rotor. Especially the output needed in industrial processes require rather high circumferential rotor speeds which thus can be in the order of 200 to 300 meters per second or even more .

A rotating rotor is generally manufactured as a cast piece or by welding pieces together, and thus there is always the risk of a breakage. A breakage can be caused e.g. by fatigue of material, manufacturing errors, foreign objects running into the device, fouling of the rotor or other unbalance therein or the like cause. The housing structures in use today cannot usually prevent pieces from a breaking rotor from being flung around and these may penetrate the peripheral structure of the housing. Especially in devices made of sheet structures rotor pieces thrown through the peripheral structure constitute a considerable factor of danger both to the surrounding structures and devices and especially to persons in the vicinity.

In order to solve the problem discussed and to control the danger factors the inventive arrangement has been developed, the characteristics of which are evident from the appended claims. Thus a protective sheath structure and, correspondingly, a device housing according to the present invention is characterized in that the arrangement comprises a protective sheath which is integrated in the peripheral structure .

One embodiment of the present invention will now be disclosed in more detail with reference to the appended drawings, wherein

Figure 1 discloses a conventional prior art fan blower structure seen in the axial direction,

Figure 2 in a side view partially in section discloses a device according to Fig. 1,

Figure 3 in a sectional view discloses a fan blower structure provided with a protective sheath according to the present invention,

Figure 4 discloses, in an enlarged sectional view A, a structure according to Fig. 3, and

Figure 5 discloses a fan blower structure in accordance with the present invention, axially seen from the opposite end.

Referring to Figures 1 and 2, in known fan blower or. the like structures a blower housing is constituted of a usually slightly helical housing structure 1 manufactured by casting or usually by welding a sheet material, in which housing 1 a compressor wheel or the like rotor 2 rotates. At the rotation the blades or the like radially extending structures 3 at said rotor force a flowable medium running in through a central inlet opening 4 towards the helical periphery of said housing 1 and finally out through an outlet opening 6 which most often is arranged tangentially. Thus, in a housing structure implemented as a sheet structure in accordance with the Figures said housing 1 is constituted of front and back sheets 7, 8 of the housing and a peripheral sheet 9 interconnecting said front and back sheets, said peripheral sheet being attached to said front and back sheets 7, 8 in a pressure proof manner, thus constituting a pressure chamber 14.

If for example a rotor blade 3 is broken during the rotation of said rotor 2 or e.g. comes loose from the shaft 10 said blade 3 or a part of it will be thrown at high speed towards said peripheral sheet 9 and will, in the worst case, penetrate it . In this situation parts hurling from said blade 3 and/or said peripheral sheet 9 will constitute a considerable factor of danger for the environment .

According to the present invention said danger can be eliminated by arranging in connection with the peripheral portion 9, in accordance with Fig. 3, a separate protective sheath 11 having a layer structure, said sheath being integrated with said peripheral structure 9. Said protective sheath will take up the kinetic energy of any piece which possibly breaks loose from said rotor 2 and thus it will efficiently prevent said piece from being flung through said peripheral structure 9 into the surroundings .

Favorably, a protective sheath according to the present invention comprises a layered elastic structure having good damping properties. Figure 4 discloses in more detail .a structure in accordance with the present invention, said Figure disclosing a favorable embodiment having a suitably unbroken flexible protecting sheath structure 11 arranged at the outside of the blower housing's 1 pressure proof peripheral sheet 9 and in the immediate vicinity thereof. Said protective sheath 11 comprises a damping structure which favorably comprises one or several cordons manufactured of fibres or the like made of steel, glass, coal or the like and having a relatively high tensile strength, said cordon being embedded in an essentially elastic material such as rubber or the like. In this manner a uniform flexible damping structure is achieved, which to its characteristics is "mat-like" . Thus said damping structure can simply be wrapped to constitute a protective sheath 11 around, e.g., the pressure-proof structure 14 of a fan blower housing 1, in spite of the fact that the shape of said housing most often is slightly helical or at least to it ' s main portions arcuate .

According to the favorable embodiment disclosed in Figure 4 said protective sheath structure 11 is attached within an extension 12, 13 made at the front and back walls 7, 8 which define said fan blower housing 1, suitably immediately outside of the peripheral structure 9 which defines the pressure chamber 14 of said housing. Traditionally, said pressure chamber 14 is sealed by an essentially leak-proof welded seam 15 which interconnect said side walls 7, 8 and said peripheral sheet 9 , but according to one embodiment of the present invention the actual sealing can also be effected through said protective sheath 11, in which case the protective sheath is favorably attached to the sheet of said peripheral structure 9, and to an appropriate extent to said extensions 12, 13 of said front and back walls 7, 8, respectively, using a glue or the like agent .

According to Figure 4, said protective sheath 11 is favorably attached to said extensions 12, 13 of said side walls 7, 8 by suitably spot-like or mainly pin like fastening elements 16 suitably being welded to the side walls, to which elements, in the embodiment disclosed, further is attached a metal sheet 17 which supports the protective sheath 11. Simultaneously, such a fastening element arrangement, which is disclosed more generally i Figure 5, will act as a general stiffening arrangement for the sheet structure, which arrangement will resist any deformations due to the internal pressure generated by the fan blower. In another embodiment the covering sheet 17 is attached as such, e.g. by welding, to the fan blower body. By integrating the protective sheath structure in the peripheral structure several advantages are achieved. A first advantage is, of course, that thereby is achieved a security in the vicinity of machinery having rotating means, which security is much better than the situation today. The integration of the protective sheath 11 directly to constitute a part of the apparatus gives a considerably more compact and simpler structure, in relation e.g. to a solution where the aim would be at the same level of security by means of external structures .

Above the present invention has been disclosed mainly by reference to a fan blower embodiment and thus the protective layer 11 will be arranged directly outside the pressure-proof peripheral structure. For the professional in this field it is evident, of course, that a corresponding protection can also be implemented in other devices comprising rotating means, where there is the risk that a rotating means would cause damage or danger if it breaks up. It is also clear that a layered flexible protective structure in some cases also can be integrated into the structure from the inside. It should also be understood that the present invention covers both such solutions wherein a protective layer 11 as described above is integrated in the apparatus at the manufacture thereof, as well as solutions where said protective sheath 11 is fastened e.g. as a post manufacture installation in an already existing device, in order to obtain an integrated structure as described above. Thus, the above specification is not intended to restrict the present invention but it should be considered to include all those alternatives and variations which are included within the scope of the appended claims.

Claims

1. A protective sheath structure intended to be arranged in connection with the peripheral structure (9) of the housing (1) of fan blower or the like device having a rotating rotor (2), c h a r a c t e r i z e d in that the arrangement comprises a layered protective sheath which is integrated especially with said peripheral structure (9) .

2. A structure as defined in claim 1, c h a r a c t e r i z e d in that said protective sheath (11) comprises a suitably uniform flexible structure having good damping properties, wherein said structure favorably can be arranged to said peripheral structure (9) suitably from the outside thereof .

3. A structure as defined in claim l or 3 , c h a r a c t e r i z e d in that said protective sheath (11) comprises one or several cordons made of fibres having a relatively high tensional strength, like steel, glass, coal or the like fibres, or a corresponding plastics material, said cordons being embedded in an essentially elastic material such as rubber or the like .

4. A structure as defined in any one of claims 1 to 3 , c h a r a c t e r i z e d in that said protective sheath (11) is arranged as an element which increases the stiffness of said housing (1) in order to reduce a deformation caused in said housing by the pressure and/or arranged as an element which simultaneously seals the pressure chamber (14) of said housing

(I) .

5. The structure of a housing (1) for a fan blower or the like device comprising a rotating rotor, c h a r a c t e r i z e d in that an integrated layered protective sheath

(II) according to any one of claims 1 to 4 is connected especially to the peripheral structure (9) of said housing (1)

6. A structure as defined in claim 5, c h a r a c t e r i z e d in that said protective sheath (11) is located within extensions (12, 13) arranged at side walls (7, 8) which define said housing (1) , suitably immediately outside said peripheral structure (9) defining said pressure chamber (14) at said housing (1) .

7. A structure as defined in claim 5 or 6, c h a r a c t e r i z e d in that said side walls (7, 8) and/or extensions (12, 13) thereof comprise one ore several separate suitably spot-like fastening elements (16) for said protective sheath (11) and any possible supporting elements (17) for said fastening elements, said fastening element arrangement (16, 17) simultaneously functioning as a general stiffening element for said structure.

8. A structure as defined in any one of claims 5 to 7, c h a r a c t e r i z e d in that said fastening element (s) (16, 17) are located outermost behind said protective sheath (11) as seen from the shaft (10) of said rotating rotor (2) .

9. A structure as defined in any one of claims 5 to 7, c h a r a c t e r i z e d in that said protective sheath (11) is located before the pressure-proof peripheral structure (9) as seen from the shaft (10) of said rotating rotor (2) .

10. A structure as defined in any one of claims 5 to 9, c h a - r a c t e r i z e d in that a layer of glue or the like material is arranged between said protective sheath (11) and said peripheral structure (9) for constituting a sealed connection between said protective sheath (11) and said peripheral structure (9) .