Global Patent Index - EP 0173778 A1

EP 0173778 A1 19860312 - Improvements relating to pumps.

Title (en)

Improvements relating to pumps.

Title (de)

Pumpen.

Title (fr)

Pompes.

Publication

EP 0173778 A1 19860312 (EN)

Application

EP 84306071 A 19840905

Priority

EP 84306071 A 19840905

Abstract (en)

A pump of the N, N+1 type has inner and outer lobed rotors designed to provide at the position of deepest mesh a clearance greater than a working clearance over the whole of the tip region to the lobe (10) of the inner rotor, a working clearance being defined at opposite circumferential sides of the said tip region at positions (18, 19) where tangents to the profile at a selected radial section (21) form a first included angle of 20 DEG or more, e.g. 54 DEG . The flanks (13, 14) of the lobe (10) define at each radial section an included angle which reduces to 20 DEG or less, but in any event less than said first included angle.

IPC 1-7

F04C 2/10

IPC 8 full level

F04C 2/08 (2006.01)

CPC (source: EP)

F04C 2/084 (2013.01)

Citation (search report)

Designated contracting state (EPC)

DE FR GB IT

DOCDB simple family (publication)

EP 0173778 A1 19860312; EP 0173778 B1 19900307; DE 3481536 D1 19900412

DOCDB simple family (application)

EP 84306071 A 19840905; DE 3481536 T 19840905