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Publication numberUS3680977 A
Publication typeGrant
Publication dateAug 1, 1972
Filing dateJun 29, 1970
Priority dateJul 1, 1969
Also published asDE2032328A1
Publication numberUS 3680977 A, US 3680977A, US-A-3680977, US3680977 A, US3680977A
InventorsMarsot Charles Louis, Rabouyt Denis
Original AssigneeMarsot Charles Louis, Rabouyt Denis
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Framed impeller
US 3680977 A
An impeller with a rotor carrying a set of fan blades has a circular duct of streamlined profile surrounding the rotor blades, the latter having their tips interconnected by a ring received with small clearance in an annular groove on the inner duct periphery so that this periphery is flush with the inner ring surface. Elastic inserts in the gap between the ring and the duct may be used to minimize or eliminate the intervening clearance.
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Description  (OCR text may contain errors)

United States Patent Rabouyt et al.

1151 3,680,977 [451 Aug 1,1972

[54] FRAMED IMPELLER [72] Inventors: Denis Rabouyt, 6 bis rue Blanche Clamart department des l-Iauts de Seine; Charles Louis Marsot, 152 Champs Elysees department de Seine 75, both of Paris, France 221 Filed: June 29,1970

21 Appl. No.: 50,052

[30] Foreign Application Priority Data July 1, 1969 5 France ..6922183 [52] US. Cl. ..415/172, 277/65, 415/210 [51] Int. Cl. ..F0ld 9/00, F16j 15/38 [58] Field of Search ..415/170, 171,172, 173, 174, 415/210; 277/65, 95

[56] References Cited UNITED STATES PATENTS 1,876,067 9/1932 Lorenzen ..415/172 10/1960 Stalker ..415/172 2,956,733 3,112,610 12/1963 Jerger ..60/221 3,306,223 2/1967 Liebig ..415/173 A 3,531,214 9/1970 Abramson ..415/119 3,519,367 7/1970 Lariviere ..415/185 FOREIGN PATENTS OR APPLICATIONS 314,062 l/l934 Italy ..415/172 Primary Examiner-l-lenry F. Raduazo Attorney-Karl F. Ross [57] ABSTRACT An impeller with a rotor carrying a set of fan blades has a circular duct of streamlined profile surrounding the rotor blades, the latter having their tips interconnected by a ring receivedwith small clearance in an annular groove on the inner duct periphery so that this periphery is flush with the inner ring surface. Elastic inserts in the gap between the ring and the duct may be used to minimize or eliminate the intervening clearance.

3 Claims, 9 Drawing Figures PATENTEDAUB' 1 I972 SHEET 1 OF 3 v Y Denis Rabouyf Charles Louis Marsof I N VEN TORS PATENTEDAUB 1 I972 SHEET 2 BF 3 Denis Rabo Charles L. :INVE

uyf Marsof N TORS'.

Attorney P'A'TENTEDAUQ 1 I972 SHEH 3 UF 3 FIG. 9

FIG. 8

Denis Rabouyf Charles L. Marsof I N VEN TOR S.

Attorney FRAMED IMPELLER Our present invention relates to an impeller, such as a blower or fan, for circulating air or some other ambient fluid.

The intensity of a flow generated by such an impeller can be enhanced by channeling this flow through a short duct or shroud of air-foil cross-section presenting a streamlined profile to the fluid stream, this duct framing the rotor of the impeller whose blades terminate at a short distance from the inner duct periphery. The duct has the dual purpose of concentrating the flow by converging in the direction of fluid passage and of minimizing turbulence in a zone surrounding the rotor blades with resulting increase in operating efficiency. The latter function, of course, calls for a minimum spacing between the blade tips and the stationary duct, yet a certain tolerance must always be maintained to allow for unavoidable eccentricities of the rotor mounting with reference to the duct axis.

Attempts to minimize this tolerance by interconnecting the free ends of the blades with the aid of a concentric ring inside the duct have not solved the problem. Though such a ring reinforces the rotor structure, it does not eliminate existing eccentricities and requires, therefore, a certain radial spacing from the duct in order to prevent contact between the two relatively rotating bodies. Moreover, the presence of such a ring diminishes the effectiveness of the rotor, by reducing the cross-sectional area of the channel swept by the blades, and creates added discontinuities giving rise to further turbulence. I

Thus, our invention aims at providing an improved impeller of the framed-rotor type wherein peripheral turbulence is effectively suppressed with avoidance of the aforestated drawbacks.

A- more particular object is to provide a combination of a flow-guiding duct with a ring-reinforced rotor enabling the utilization of the entire cross-sectional area of the flow channel defined by the duct for the generation of forced circulation or thrust.

These objects are realized, in accordance with our present invention, by providing the inner duct periphery with an annular groove receiving, with small clearance, a ring interconnecting the free ends of the blades, the ring preferably having a substantially flat inner peripheral surface flush with the inner duct periphery so as to form part of a channel wall free from major discontinuities.

In the simplest case, the ring may be a relatively thin ferrule of cylindrical shape somewhat smaller than the relative shallow groove. In a more sophisticated arrangement, designed to throttle the fluid flow through the meandering gap between the ring and the groove wall, this gap may be further reduced or eliminated with the aid of preferably elastic sealing means in actual or potential contact with the rigid ring. The latter may be formed with one or more outwardly directed radial flanges which, in co-operation with an insert or filler interleaved therewith, lengthen the flow path around the rotor periphery and which could also be used to shield a set of swivel heads in the ring facilitating an adjustment of the blade pitch.

The problem of fitting the blade ring in the groove of the duct may be solved in various ways, as by making the duct in several axially or peripherally adjoining sections or by molding the duct directly about the rotor. If the ring is a sufiiciently deformable ferrule, it could also be'snapped into the groove of an integrally constructed duct.

The above and other features of our invention will be described in detail with reference to the accompanying drawing in which:

FIG. 1 is an axial view, partly in section, of an impeller embodying-our invention;

FIG. 2 is a face'view of the impeller shown in FIG. 1;

FIG. 3 is a fragmentary sectional view taken on the line III III of FIG. 2 but drawn to a larger scale;

FIGS. 4 and 5 show, on a still larger scale, modifications of the assembly illustrated in FIG. 3;

FIGS. 6 and 7 are enlarged views generally similar to FIG. 3, showing further modifications; and

FIGS. 8 and 9 are views similar to part of FIG. 5, illustrating yet other variants.

In FIGS. 1-3 we have shown an impeller which may be used as an air screw on an aircraft not further illustrated and which comprises a motor 1 driving a streamlined hub 2 of a rotor having several (here four) propeller blades 3 radiating from that hub. The free ends of these blades are interconnected by a ring 4 in the form of a thin ferrule received within an annular groove 8 on the inner peripheral surface 7 of a duct or shroud 5 of streamlined cross-section. Duct 5 is supported by struts 6 on the stationary engine housing of motor 1.

As best seen in FIG. 3, the inner peripheral surface 4a of ring 4 is flush with the inwardly convex surface 7 of duct 5 so as to define therewith a substantially continuous channel wall. The circular edges 10 of ring 4 are closely spaced from similar edges 9 of a sheet-metal sheath 5a which envelops the body of duct 5 and extends slightly past the sides of groove 8.

The thrust of the propeller shown in FIGS. 1-3 is somewhat diminished by an equalizing flow passing through the narrow gap between edges 9 and. 10 from the high-pressure region behind the rotor blades 3 to the low-pressure region ahead of these blades. This bypass path canbe blocked, as shown in FIG. 4, by the provision of a seal generally designated 11. Seal 11 comprises a pair of strips l2, 13, of rubber or other elastomeric material, mounted on a pair of shoulders 5, 5" which are formed by the projecting edges of sheath 5a inside groove 8 so as to bear upon the outer peripheral surface of ring 4. FIG. 4 also shows a screw 24 serving to fasten this ring to a corresponding blade 3.

In FIG. 5 we have illustrated a modified ring 4 of U- profile formed with two radial flanges l4, 15 received in the groove.8. Sealing strips 16 and 17, similar to those of the preceding embodiment, bear upon the outer surfaces of these flanges at locations spaced radially outwardly from the supporting shoulders 5,5".

According to FIG. 6, the flanged ring 4' co-operates with a tripartite insert, also preferably of elastic material, consisting of three labyrinth sections 18, 18' and 18" axially separated by narrow gaps which receive the ring flanges l4 and I5.

As shown in FIG. 7, an elastic filler 19 of polyurethane foam or other cellular material forms similar annular recesses 19a, 19b to accommodate the flanges l4 and 15. a

FIGS. 8 and 9 illustrate the possibility of using a flanged ring 4' as a journal bearing for the rotor blades 3 whose pitch can be controlled from within the hub 2 (FIG. 1), by conventional means not shown, and which terminate in studs 20 (FIG. 8) or 20' (FIG. 9) received in respective sockets 22, 23. These sockets may be formed by individual bosses, as in FIG. 8, or by a continuous hollow ridge, as in FIG. 9, with interposition of bearing sleeves 25, 25' around the studs. FIG. 9 shows the bearing sleeve 25' as a spherically convex bushing 21 on stud 20'. Antifriction layers (e.g. of Teflon), not shown, may be inserted between these bearing sleeves and the coacting stud surfaces.

We claim:

1. An impeller for the circulation of an ambient fluid, comprising a rotor with a set of blades radiating from an axis; a circular duct of airfoil cross-section fixedly centered on said axis, said duct having an inner periphery provided with an annular groove and lined with a sheet-metal sheath projecting beyond the edges of said groove to form a pair of annular shoulders within said groove; a ring centered on said axis and interconnecting said blades, said ring projecting radially into said groove with small axial clearance from said shoulders; and sealing means in said groove bridgeing said axial clearance, said sealing means including a pair of elastic annular strips mounted in said groove on said shoulders and extending therefrom into contact with said ring.

2. An impeller as defined in claim 1 wherein said ring has a substantially flat inner peripheral surface flush with the inner periphery of said sheath.

3. An impeller as defined in claim 1 wherein said ring is provided with two outwardly directed radial flanges confronting said shoulders, said strips bearing upon said flanges at locations spaced radially outwardly from said sheath.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1876067 *Sep 15, 1927Sep 6, 1932Bendix Aviat CorpBlade structure for turbines
US2956733 *Sep 28, 1954Oct 18, 1960Stalker CorpFluid turning wheels for compressors
US3112610 *Feb 27, 1961Dec 3, 1963Joseph J JergerConstant pressure shrouded propeller
US3306223 *Oct 22, 1964Feb 28, 1967Illinois Milling IncWater pump seal
US3519367 *May 23, 1968Jul 7, 1970Nord Aviat Soc Nationale De CoAuxiliary faired section for a fluid inlet
US3531214 *Dec 9, 1968Sep 29, 1970Franz W AbramsonRadial-driven,multistage jet pump
IT314062A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3932055 *Aug 5, 1974Jan 13, 1976Flatland Lloyd PVacuum turbine for a drill
US3986787 *Oct 15, 1975Oct 19, 1976Mouton Jr William JRiver turbine
US4131156 *Oct 12, 1976Dec 26, 1978Caterpillar Tractor Co.Fan shroud
US4238170 *Jun 26, 1978Dec 9, 1980United Technologies CorporationBlade tip seal for an axial flow rotary machine
US4398508 *Feb 20, 1981Aug 16, 1983Volvo White Truck CorporationEngine cooling fan construction
US4406581 *Dec 30, 1980Sep 27, 1983Hayes-Albion Corp.Shrouded fan assembly
US4441859 *Jan 20, 1982Apr 10, 1984Rolls-Royce LimitedRotor blade for a gas turbine engine
US4457519 *Jun 4, 1982Jul 3, 1984Harrington George HSealing ring
US4491330 *Aug 1, 1983Jan 1, 1985Franklin Electric Co., Inc.Rotary lip seal
US4548548 *May 23, 1984Oct 22, 1985Airflow Research And Manufacturing Corp.Fan and housing
US4580946 *Nov 26, 1984Apr 8, 1986General Electric CompanyFan blade platform seal
US4596054 *Jul 3, 1984Jun 24, 1986Air-Lock, IncorporatedPressure sealing bearing assembly for use in environmental control suits and environmental suits containing such bearing assemblies
US4949022 *Jan 27, 1989Aug 14, 1990Lipman Leonard HSolid state DC fan motor
US5075606 *Aug 14, 1990Dec 24, 1991Lipman Leonard HSolid state DC fan motor
US5183382 *Sep 3, 1991Feb 2, 1993Caterpillar Inc.Low noise rotating fan and shroud assembly
US5577888 *Jun 23, 1995Nov 26, 1996Siemens Electric LimitedHigh efficiency, low-noise, axial fan assembly
US5740766 *Mar 25, 1997Apr 21, 1998Behr America, Inc.Automotive fan and shroud assembly
US5791876 *Mar 25, 1997Aug 11, 1998Behr America, Inc.Floating drive assembly for an automotive cooling fan
US5906179 *Jun 27, 1997May 25, 1999Siemens Canada LimitedHigh efficiency, low solidity, low weight, axial flow fan
US5957661 *Jun 16, 1998Sep 28, 1999Siemens Canada LimitedHigh efficiency to diameter ratio and low weight axial flow fan
US6065937 *Jun 10, 1998May 23, 2000Siemens Canada LimitedHigh efficiency, axial flow fan for use in an automotive cooling system
US6450760 *Nov 20, 2000Sep 17, 2002Komatsu Ltd.Fan device
US6471472Aug 25, 2000Oct 29, 2002Siemens Canada LimitedTurbomachine shroud fibrous tip seal
US6508624 *May 2, 2001Jan 21, 2003Siemens Automotive, Inc.Turbomachine with double-faced rotor-shroud seal structure
US6874990 *Feb 10, 2003Apr 5, 2005Siemens Vdo Automotive Inc.Integral tip seal in a fan-shroud structure
US6899339 *Aug 30, 2001May 31, 2005United Technologies CorporationAbradable seal having improved durability
US7481615 *Mar 27, 2006Jan 27, 2009Halla Climate Control Corp.Fan and shroud assembly
US7549841Sep 1, 2006Jun 23, 2009Florida Turbine Technologies, Inc.Pressure balanced centrifugal tip seal
US7997870Aug 14, 2007Aug 16, 2011B N Balance Energy Solutions, LlcTurbine rotor for electrical power generation
US8870531 *Dec 11, 2009Oct 28, 2014SnecmaTurbomachine rotor having blades of composite material provided with metal labyrinth teeth
US20040156712 *Feb 10, 2003Aug 12, 2004Siemens Vdo Automotive Inc.Integral tip seal in a fan-shroud structure
US20100158675 *Dec 11, 2009Jun 24, 2010SnecmaTurbomachine rotor having blades of composite material provided with metal labyrinth teeth
US20120087791 *Jan 22, 2010Apr 12, 2012Johannes Waarseth-JungeWind turbine device
US20120301277 *Nov 29, 2012Chih-Hsiang ChangFan
DE2648850A1 *Oct 27, 1976May 18, 1977Hitachi LtdAxialluefter
EP1001138A1 *Nov 10, 1998May 17, 2000Asea Brown Boveri AGTurbine blade tip sealing
EP1426559A1 *Dec 3, 2002Jun 9, 2004Techspace Aero S.A.Inner shroud for an axial compressor
EP2184804A1 *Aug 28, 2009May 12, 2010Honeywell InternationalDucted fan unmanned aerial vehicle conformal antenna
EP2570341A1 *Sep 13, 2012Mar 20, 2013Becker Marine Systems GmbH & Co. KGPropeller nozzle
WO2001083950A1 *May 2, 2001Nov 8, 2001Siemens Automotive IncTurbomachine with rotor-shroud seal structure
U.S. Classification415/173.6, 277/419, 416/192, 277/369, 415/210.1, 277/562, 415/174.2, 277/414, 415/174.5, 416/190, 277/402
International ClassificationB63H5/00, F01D11/08, B63H5/15, B64C11/00
Cooperative ClassificationF01D11/08, B64C11/001
European ClassificationB64C11/00B, F01D11/08