GELLING JACON LOURENS (NL)
| GB1324356A | 1973-07-25 | |||
| US4637801A | 1987-01-20 | |||
| DE883255C | 1953-07-16 | |||
| FR1381494A | 1964-12-14 | |||
| BE447117A | ||||
| DE941048C | 1956-03-29 |
| 1. | 5 replaced by amended claims 1. 4 (1 page)] '1 ».v 1 A double nozzle, consisting of a main nozzle (1) in which a propeller operates, having blades (4) on a hub (5) , and a flap nozzle (2) , coaxially located and operating in conjunction with the main nozzle, an opening (6) being 5. formed between the two nozzles by the rearward thin part (la) of the main nozzle (1) and the front part (2a) of the flap nozzle (2) , said opening (6) extending rearwardly and inwardly, the rear edge of the main nozzle (1) and the smallest diameter of the flap nozzle (2) lying sub. 10 stantially in one radial plane such that there is a jump in the inside surfaces of the two nozzles. |
| 2. | A double nozzle according to claim 1, characterized in that main nozzle (1) and flap nozzle (2) are connected 15 by extended parts of the nozzle construction. |
| 3. | A double nozzle according to claim 1 or 2, characterized in that the connection consists of radial stiffening plates. |
| 4. | A double nozzle according to one or more of the 30 foregoing claims, characterized in that it is connected to the fixed pitch propeller blade tips. STATEMENTUNDERARTICLE19 In the new main claim GB. A. 1,324,356 is considered as the state of the art. Said patent shows a double nozzle construction in which the inner surfaces of the nozzles lie approximately on a common smooth curve. This is indicated in the lines 26. 30 of page 1 of said patent and is also shown in the accompanying drawin . This condition of "smoothness" is usual in aero. and hydro¬ dynamics. It is precisely by ignoring this conventional wisdom that the present invention achieves an improvement in respect of the known device. In view of this claim 4 of the original filed specification was incorporated in the main claim. In the new main claim also the position of the "jump" is more exactly indicated. This positioning was clearly indicated in Fig. 2 of the application as filed. Concerning US. A. 4,637,801 it can be remarked that Fig. 4 of this patent shows that the diffusor angle is negative, which means an inward flow at the trailing edge of the nozzle. Fig. 4 also shows a negative camber of the foreward nozzle profile. A negative diffusor and negative camber have a favourable effect on propeller cavitation of high speed craft for which the related patent is obviously intended but have a decreasing effect on the efficiency. The construction according to the present invention is having positive camber and a positive diffusor angle. By this the efficiency is improved in particular by the relatively large positive diffusor angle. By the construction according to the above mentioned US patent only the efficiency will be improved at hig propeller loading, i.e. during take. off or in towing condition (see column 1, line 14 and column 2, lines 54. 57) . A main object of the present invention is that also in free running condition an improvement in propulsive a '( efficiency is achieved, in particular by means of its *" positive camber and diffusor angle in combination with an appropriate opening between the two profiles. DE. C. 883,255 shows a construction in which the propeller blade tips lie immediately aft of the slot between the two nozzles. A serious drawback of this is that vortices coming from the slot impinge on the blade tips which results in cavitation erosion on the blades. In case of the present patent application the propeller operates within the main nozzle, i.e. forward of the opening between the two nozzles. FR. A. 1,381 ,494 shows a construction in which the second nozzle is located behind the first nozzle so there is no overlap between the two nozzle profiles. BE. A. 447,117 shows a construction for which the same holds as remarked in case of DE. C. 883 ,255. DE. C. 941,048 shows a construction which differs fundamentally in various aspects from the present invention as appears directly from considering the drawing of said patent. AMENDED CLAIMS [received by the International Bureau on 12 January 1990 (12.01.90). original claims 1. 5 replaced by amended claims 1. 4 (1 page)] 1 A double nozzle, consisting of a main nozzle (1) in which a propeller operates, having blades (4) on a hub (5) , and a flap nozzle (2) , coaxially located and operating in conjunction with the main nozzle, an opening (6) being formed between the two nozzles by the rearward thin part (la) of the main nozzle (1) and the front part (2a) of the flap nozzle (2) , said opening (6) extending rearwardly and inwardly, the rear edge of the main nozzle (1) and the smallest diameter of the flap nozzle (2) lying sub. stantially in one radial plane such that there is a jump in the inside surfaces of the two nozzles. |
| 5. | 2 A double nozzle according to claim 1, characterized in that main nozzle (1) and flap nozzle (2) are connected by extended parts of the nozzle construction. |
| 6. | 3 A double nozzle according to claim 1 or 2, characterized in that the connection consists of radial stiffening plates. |
| 7. | 4 A double nozzle according to one or more of the foregoing claims, characterized in that it is connected to the fixed pitch propeller blade tips. STATEMENTUNDERARTICLE 19 In the new main claim GB. A. 1,324,356 is considered as the state of the art. Said patent shows a double nozzle construction in which the inner surfaces of the nozzles lie approximately on a common smooth curve. This is indicated in the lines 26. 30 of page 1 of said patent and is also shown in the accompanying drawing. This condition of "smoothness" is usual in aero. and hydro¬ dynamics. It is precisely by ignoring this conventional wisdom that the present invention achieves an improvement in respect of the known device. In view of this claim 4 of the original filed specification was incorporated in the main claim. In the new main claim also the position of the "jump" is more exactly indicated. This positioning was clearly indicated in Fig. 2 of the application as filed. Concerning US. A. 4r637,801 it can be remarked that Fig. 4 of this patent shows that the diffusor angle is negative, which means an inward flow at the trailing edge of the nozzle. Fig. 4 also shows a negative camber of the foreward nozzle profile. A negative diffusor and negative camber have a favourable effect on propeller cavitation of high speed craft for which the related patent is obviously intended but have a decreasing effect on the efficiency. The construction according to the present invention is having positive camber and a positive diffusor angle. By this the efficiency is improved in particular by the relatively large positive diffusor angle. By the construction according to the above mentioned US patent only the efficiency will be improved at high propeller loading, i.e. during take. off or in towing condition (see column 1, line 14 and column 2, lines 54. 57) . A main object of the present invention is that also in free running condition an improvement in propulsive efficiency is achieved, in particular by means of its positive camber and diffusor angle in combination with an appropriate opening between the two profiles. DE. C. 883,255 shows a construction in which the propeller blade tips lie immediately aft of the slot between the two nozzles. A serious drawback of this is that vortices coming from the slot impinge on the blade tips which results in cavitation erosion on the blades. In case of the present patent application the propeller operates within the main nozzle, i.e. forward of the opening between the two nozzles. FR. A. 1,381 ,494 shows a construction in which the second nozzle is located behind the first nozzle so there is no overlap between the two nozzle profiles. BE. A. 447,117 shows a construction for which the same holds as remarked in case of DE. C. 883,255. DE. C. 941,048 shows a construction which differs fundamentally in various aspects from the present invention as appears directly from considering the drawing of said patent. Claims : 1 A double nozzle, consisting of a main nozzle (1) and a flap nozzle (2) , coaxially located and operating in conjunction with the main nozzle (1) , an opening (6) being formed between the two nozzle profiles by the thin part (la) of main nozzle (1) and the front part (2a) of flap nozzle (2) , opening (6) extending rearwardly and inwardly. |
| 8. | 1 A double nozzle according to claim 1, characterised in that main nozzle (1) and flap nozzle (2) are connected by extended parts of the nozzle construction. |
| 9. | 3 A double nozzle according to claim 1 or 2, character¬ ised in that the connection consists of radial stiffening plates . |
| 10. | 4 A double nozzle according to one or more of the foregoing claims, characterised in that the inside of flap nozzle (2) shows an outward jump (larger diameter) with respect to the inside of main nozzle (1). |
| 11. | A double nozzle according to one or more of the foregoing claims, characterised in that it is connected to the fixed pitch propeller blade tips. |
PCT WORLD INTELLECTUAL PROPERTY ORGANIZATION International Bureau
INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
(51) International Patent Classification 4 (11) International Publication Number: WO 89/11 B63H 5/14, 1/16 Al
(43) International Publication Date: 14 December 1989 (14.1
(21) International Application Number: PCT/NL89/00039 (74) Agent: LIPS, H., J., G.; Breitnerlaan 146, NL-2596 Den Haag (NL).
(22) International Filing Date : 1 June 1989 (01.06.89)
(81) Designated States: AT (European patent), AU, BB,
(30) Priority data: (European patent), BF (OAPI patent), BG, BJ (O
8801402 1 June 1988 (01.06.88) NL patent), BR, CF (OAPI patent), CG (OAPI patent), (European patent), CM (OAPI patent), DE, DE (E pean patent), DK, FI, FR (European patent), GA (O
(71) Applicant (for all designated States except US): VAN GUN- patent), GB (European patent), HU, IT (European
STEREN & GELLING MARINE PROPULSION DE¬ tent), JP, KP, KR, LK, LU (European patent), MC, VELOPMENT B.V. [NL/NL]; Kalfjeslaan 12, NL-2623 ML (OAPI patent), MR (OAPI patent), MW, NL (E AH Delft (NL). pean patent), NO, RO, SD, SE (European patent), (OAPI patent), SU, TD (OAPI patent), TG (OAPI
(72) Inventors; and tent), US.
(75) Inventors/Applicants (for US only) : VAN GUNSTEREN, Leonard, Anthonie [NL/NL]; Koningin Astrid Boule¬ vard 39, NL-2202 BG Noordwijk (NL). GELLING, Jac- on, Lourens [NL/NL]; Reimsstraat 49, NL-2711 EV Zoetermeer (NL). Published
With international search report With amended claims and statement
Date of publication of the amended claims and statement:
8 February 1990 (08.02.
(54) Title: DOUBLE NOZZLE
(57) Abstract
Double nozzle consisting of a main nozzle (1) and a flap nozzle (2), coaxially located and operating in conjunction w main nozzle (1), comprising an opening (6) formed between the two nozzle profiles by the thin part (la) of main nozzle (1) a the front part (2a) of flap nozzle (2), said opening (6) extending rearwardly and inwardly. Main nozzle (1) and flap nozzle may be interconnected by extended parts of the nozzle construction, such as radial stiffening plates.
FOR THE PURPOSES OF INFORMATION ONLY
Codes used to identify States party to the PCT on the front pag-ss of pamphlets publishing international
AT Austria εs Spain MG Madagascar
AU Australia FT Finland ML Mali
BB Barbados FR France MR Mauritania.
BE Belgium GA Gabon MW Malawi
BF Burkina Fasso GB United Kingdom NL Netherlands
BG Bulgaria HU Hungary NO Norway
BJ Benin IT Italy RO Romania
BR Brazil JP Japan 9) Sudan
CA Canada KP Democratic People's Republic SE Sweden
CF Central African Republic of Korea SN Senegal
CG Congo KR Republic of Korea sυ Soviet Union
CH Switzerland U Liechtenstein TO ■ Chad
CM Cameroon LI Sri Lanka TG Togo
DE Gennany, Fiederal Republic of LU Luxembourg US United States of America
DK Denmark MC Monaco