Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberDE4091862 T
Publication typeApplication
Application numberDE19904091862
Publication date21 Nov 1991
Filing date15 Nov 1990
Priority date15 Nov 1989
Also published asCA2045537A1, US5018574, WO1991007567A1
Publication number19904091862, 904091862, DE 4091862 T, DE 4091862T, DE-T-4091862, DE19904091862, DE4091862 T, DE4091862T, DE904091862
Export CitationBiBTeX, EndNote, RefMan
External Links: DPMA, Espacenet

DE 4091862 T
Abstract  available in
Description  available in
Claims  available in
Classifications
International ClassificationE21B47/10, E21B17/06, E21B33/127
Cooperative ClassificationE21B17/06, E21B47/10, E21B33/127
European ClassificationE21B47/10, E21B17/06, E21B33/127
Legal Events
DateCodeEventDescription
20 Mar 19978128New person/name/address of the agent
Representative=s name: PATENTANWAELTE MUELLER & HOFFMANN, 81667 MUENCHEN
29 Jan 19988110Request for examination paragraph 44
12 Feb 19988125Change of the main classification
Ipc: E21B 47/10
23 Mar 20008607Notification of search results after publication
11 Jan 20018139Disposal/non-payment of the annual fee