| 摘要 |
A syringe includes a gasket, a barrel, and a plunger. The plunger includes a helical rib provided at a head portion, and the gasket includes a threaded engagement portion configured to threadedly engaged with the helical rib, a plunger-retaining annular rib, and an accommodation portion for accommodating a part of the plunger at which the helical rib is formed. The annular rib includes a rib absent portion for guiding, to the accommodation portion, the helical rib reaching the annular rib. The gasket further includes an intermediate annular rib provided at a part on a proximal side of the retaining annular rib and a part defined on a side of the distal end of the helical projection, between a distal side annular rib and a proximal side annular rib. |
| 主权项 |
1. A syringe comprising:
a cylindrically-shaped gasket comprising a closed distal end, an open proximal end, and an inner cavity portion extending distally from a proximal side; a barrel comprising a distal opening portion, the barrel configured to slidably accommodate the gasket; and a plunger comprising a head portion configured to be accommodated in the inner cavity portion of the gasket and a helical rib disposed on an outer surface of the head portion, wherein the gasket comprises, on an inner surface of the inner cavity portion, a helical projection forming a threaded engagement portion configured to threadedly engage with the helical rib of the plunger and a plunger retaining annular rib positioned on a distal side near the helical projection, wherein the inner cavity portion further comprises an accommodation portion positioned distally from the plunger retaining annular rib, the accommodation portion configured to accommodate a part of the head portion of the plunger at which the helical rib is formed, and wherein the plunger retaining annular rib comprises a rib absent portion for guiding, to the accommodation portion, the helical rib reaching the plunger retaining annular rib as threaded engagement is advanced between the plunger and the gasket, and wherein the gasket comprises, on an outer peripheral surface, a distal side annular rib having an outer diameter larger than an inner diameter of the barrel, a proximal side annular rib having an outer diameter larger than the inner diameter of the barrel, and an intermediate annular rib disposed between the distal side annular rib and the proximal side annular rib and at a part defined on a side of the plunger retaining annular rib. |
