EP 0308846 B1 19911016 - METHOD FOR STARTING VACUUM PUMPS CONNECTED IN SERIES, AND DEVICE FOR CARRYING OUT THE METHOD
Title (en)
METHOD FOR STARTING VACUUM PUMPS CONNECTED IN SERIES, AND DEVICE FOR CARRYING OUT THE METHOD
Publication
Application
Priority
FR 8713267 A 19870925
Abstract (en)
[origin: JPH01106980A] PURPOSE: To start a vacuum pump in an ensured way without using a pressure gage by starting a secondary pump when the suction pressure of a primary pump as reduced by rotation of the primary pump reaches an acceptable value. CONSTITUTION: When pump movement is to be started, a switch I is first turned on to start a primary pump A. A contactor 12 is closed and a motor M1 is rotated. At this start time, a contactor 31 is closed. However, the closure of a contactor 13 is delayed. The time delay of the contactor 13 is designed such that the contactor 13 is closed after the contactor 31 is opened. When the suction pressure of the pump A is reduced to a predetermined threshold value, the absorbed power is reduced, the feed current is also reduced, and the excitation of a current relay 30 is stopped. The contactor 31 is closed and current is fed to a coil 21 of a relay 20. As a contactor 22 is closed, a pump B is started.
IPC 1-7
IPC 8 full level
F04B 37/14 (2006.01); F04B 37/16 (2006.01); F04B 41/06 (2006.01); F04B 49/00 (2006.01); F04B 49/02 (2006.01); F04B 49/06 (2006.01)
CPC (source: EP US)
F04B 37/14 (2013.01 - EP US); F04B 41/06 (2013.01 - EP US); F04B 49/02 (2013.01 - EP US)
Citation (examination)
Catalogue de la société Leybold -Heraeus (173.1.3. HV 254 . Section 3, Nouvelle Edition 04/83
Designated contracting state (EPC)
AT BE CH DE ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
EP 0308846 A1 19890329; EP 0308846 B1 19911016; AT E68565 T1 19911115; DE 3865615 D1 19911121; ES 2026620 T3 19920501; FR 2621141 A1 19890331; FR 2621141 B1 19891201; GR 3003251 T3 19930217; JP H01106980 A 19890424; JP H0238796 B2 19900831; US 4887941 A 19891219
DOCDB simple family (application)
EP 88115311 A 19880919; AT 88115311 T 19880919; DE 3865615 T 19880919; ES 88115311 T 19880919; FR 8713267 A 19870925; GR 910401879 T 19911202; JP 23747188 A 19880921; US 24915488 A 19880926