Safety device for a syringe is constituted by a body, a needle carrier, a
piston, and a piston plunger. The device includes a sheath and a body. The
syringe body may slide axially inside the sheath between an injection
position and a safe position. A return member urges the syringe body
towards the safe position, and may be triggered automatically when the
piston plunger is pushed into the body. A telescopic head is capable of
taking up a retracted position and an extended position. A combination for
locking the telescopic head in the extended position may be constituted by
a combination of two oppositely-directed axial bearing surfaces bearing
against two oppositely-directed axial bearing surfaces of the sheath, and
two oppositely-directed lateral bearing surfaces which bear against two
oppositely-directed lateral bearing surfaces of the sheath.
