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. 27, 1993
Filed:
Jul. 19, 1991
Alan C Allison, Pacifica, CA (US);
Richard A Jaffe, Palo Alto, CA (US);
Other;
Abstract
A locking device is capable of being retrofitted by insertion into a standard plastic syringe. The syringe is of the type having a cylindrical inner wall made of plastic material, a closed, distal end, and an open, proximal end for movement of a plunger therein. The plunger has a plunger stem made of plastic material with longitudinal ribs in an 'X' shaped cross-section. The locking device has a clip-type body portion formed with a U-shaped channel for clipping onto one longitudinal rib, a first set of barbed points angled toward the plunger stem for engaging the plunger stem when it is depressed toward the distal end after a first retraction movement toward the proximal end of the syringe, and a second set of barbed points angled toward the inner wall of the syringe for engaging the inner wall in order to lock the plunger stem from a second retraction movement, thereby preventing reuse of the syringe. Another spring-type version of the locking device is formed from a single piece of rhombic-shaped sheet metal with an arched spring shape, one pair of barbed points on opposing lateral edges, and another barbed point at a point of the rhombic-shaped metal.