Patent ID: 7455659
Filing Date: 2008-11-25
Classification: A61M

Abstract:
1. A liquid injection system, comprising: a liquid injector having a piston actuating mechanism for holding and sliding a piston flange of a normal syringe; a rodless syringe having a slender cylinder having an opening defined in an end thereof and a piston having a piston head free of a piston rod and having a piston flange directly formed on an end of the piston head, said piston being slidably inserted in said cylinder through said opening; and a slender piston adapter for use with said rodless syringe instead of the normal syringe in said liquid injector and interconnecting the piston flange of said rodless syringe and said piston actuating mechanism of said liquid injector; said piston adapter comprising: a slender adapter rod having a first end and a second end, and an adapter flange for being held by said piston actuating mechanism, said adapter flange being disposed on an outer circumferential edge of the first end of the adapter rod; a flange holding mechanism mounted on the second end of said adapter rod for releasably holding the piston flange of said rodless syringe, said flange holding mechanism comprises at least one engaging claw openably and closably supported on said adapter rod for releasably holding the piston flange of said rodless syringe and a closing mechanism for normally biasing said engaging claw in a closing direction; a manual operating member disposed on said adapter rod near the first end thereof for being manually operated; and an interlink mechanism for at least releasing said flange holding mechanism from said piston flange in conjunction with manual operation of said manual operating member; wherein said manual operating member is longitudinally slidably supported on said adapter rod, and said flange holding mechanism comprises a plurality of engaging claws, said interlink mechanism comprising: a slender open interlocking mechanism having an end coupled to said manual operating member and a wedge-shaped member disposed on an opposite end thereof for spreading said engaging claws away from each other when said open interlocking mechanism is slid toward the first end of said adapter rod; and a biasing mechanism for normally biasing said open interlocking mechanism toward the second end of said adapter rod.