EP 0988453 A1 20000329 - SCREW SPINDLE VACUUM PUMP AND OPERATING METHOD
Title (en)
SCREW SPINDLE VACUUM PUMP AND OPERATING METHOD
Title (de)
SCHRAUBENSPINDELVAKUUMPUMPE UND VERFAHREN ZUM BETRIEB DERSELBEN
Title (fr)
POMPE A VIDE A VIS ET SON PROCEDE DE FONCTIONNEMENT
Publication
Application
Priority
- DE 19724643 A 19970611
- EP 9803544 W 19980609
Abstract (en)
[origin: US6273696B1] Screw-spindle vacuum pump with at least three closed-off feed chambers located one behind the other along each rotor and method for operating this compressor. The chamber which is last on the delivery side is brought virtually to the compression limit pressure by means of pre-admission, shortly before it opens towards the delivery side, by supplying a pre-admission stream which is at least five times as great as the intake mass stream. A precondition, in this case, is a minimum ratio of external compression to internal compression of five.
IPC 1-7
IPC 8 full level
F04C 18/16 (2006.01); F04C 25/02 (2006.01); F04C 29/00 (2006.01); F04C 29/04 (2006.01)
CPC (source: EP KR US)
F04C 29/04 (2013.01 - EP KR US); F04C 2240/402 (2013.01 - EP US)
Citation (search report)
See references of WO 9857067A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB IE IT LI NL PT SE
DOCDB simple family (publication)
US 6273696 B1 20010814; AT E247780 T1 20030915; CA 2293618 A1 19981217; CA 2293618 C 20070918; DE 19724643 A1 19981217; DE 59809350 D1 20030925; DK 0988453 T3 20031215; EP 0988453 A1 20000329; EP 0988453 B1 20030820; ES 2206958 T3 20040516; JP 2002504205 A 20020205; JP 4002304 B2 20071031; KR 100340166 B1 20020610; KR 20010013629 A 20010226; KR 20010013692 A 20010226; NO 327604 B1 20090831; NO 996129 D0 19991210; NO 996129 L 19991210; PT 988453 E 20040130; WO 9857067 A1 19981217; ZA 984959 B 19990412
DOCDB simple family (application)
US 44570599 A 19991209; AT 98934953 T 19980609; CA 2293618 A 19980609; DE 19724643 A 19970611; DE 59809350 T 19980609; DK 98934953 T 19980609; EP 9803544 W 19980609; EP 98934953 A 19980609; ES 98934953 T 19980609; JP 50163099 A 19980609; KR 19997011639 A 19991210; KR 19997011707 A 19991211; NO 996129 A 19991210; PT 98934953 T 19980609; ZA 984959 A 19980609