The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1998
Filed:
Jul. 22, 1997
Applicant:
Inventors:
Birger Hjertman, Hasselby, SE;
Olle Ljungquist, Taby, SE;
Assignee:
Pharmacia & Upjohn Aktiebolag, Stockholm, SE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
A61M / ;
U.S. Cl.
CPC ...
604218 ; 604219 ;
Abstract
A piston (11) to be used in displacing a liquid inside a cylindrical chamber, such as in an injection cartridge of the dual-chamber type, has at least one of its end surfaces (12) shaped convex such that said end surface or surfaces (12) are essentially planar when the piston has been arranged inside the barrel of said cartridge. Preferably both pistons in the cartridge have such a shape, their planar surfaces facing each other.