To provide a hypodermic needle assembly which reduces risk of unintentional exposure of a used needle by automatically engaging a needle shield without requiring a complex mechanism or operation by a user.
This syringe is equipped with two advancing mechanisms, and includes a syringe barrel 308 having a closing end part 311 with a syringe tip end part 314 and a bore; and a plunger 310 having an extension pin 316 and a plunger tip end part 318 through which the extension pin 316 penetrates. Two kinds of force are provided by the advancing mechanisms acting on the plunger. The first force acts on the plunger to move the plunger to a second position wherein the plunger tip end part 318 is in contact with the closing end part of the syringe barrel 308 and the second force acts on the plunger tip end part 310 to move to a third position with respect to the plunger tip end part. The extension pin 316 actuates a pressure trigger part to interact with a needle tip end block means of the needle assembly installed on the syringe.
FREIGANG HELMUT
FUCHS JUERGEN
REUTER JUERGEN
SIEMON KLAUS
WENDE JOERG
HILBERG FRANK
Mitsuo Tanaka
Kawabata Junichi