(19)
(11) EP 1 132 618 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
10.07.2002 Bulletin 2002/28

(43) Date of publication A2:
12.09.2001 Bulletin 2001/37

(21) Application number: 01105738.7

(22) Date of filing: 08.03.2001
(51) International Patent Classification (IPC)7F04C 2/16
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 08.03.2000 IT BO000119

(71) Applicant: Morselli, Mario Antonio
41100 Modena (IT)

(72) Inventor:
  • Morselli, Mario Antonio
    41100 Modena (IT)

(74) Representative: Provvisionato, Paolo 
Provvisionato & Co S.r.l., Piazza di Porta Mascarella, 7
40126 Bologna
40126 Bologna (IT)

   


(54) A positive-displacement rotary pump with helical rotors


(57) A positive-displacement rotary pump comprises a pair of meshing rotors or gears (10, 11), that is, a driving rotor or gear and a driven rotor or gear, respectively, enclosed in a casing with a delivery opening and an intake opening for a fluid. The gears (10, 11) comprise a plurality of teeth (16a, 16b) meshing without encapsulation and at the same time defining sets of helical teeth with a face overlap substantially equal to or close to unity. The combination of a profile of the teeth which prevents encapsulation and of the helical arrangement of the teeth reduces ripple and the noise resulting therefrom when the pump is in operation.







Search report