A syringe system and components thereof are disclosed. The system may include a syringe body having a hollow lumen, a proximal open end, and a distal end. The syringe body may be configured to house a fluid therein. The syringe system may further include a plunger positioned in the hollow lumen of the syringe body, forming a seal with an inner wall of the syringe body. The plunger may include a removable piston having a shaft extending from the distal end towards the proximal open end, a stopper removably connected to a distal portion of the shaft, and at least one coupler attached to the distal portion of the shaft. The stopper may be configured to slidably move within the hollow lumen to facilitate movement of the fluid within the syringe body. The coupler may be configured to facilitate removal and attachment of the stopper from the piston.

An injection device includes one or more of a barrel having an open proximal end, an open distal end, and a sidewall therebetween; a plunger; and a conduit or connector. The barrel may be configured to house a volume of therapeutic agent. The plunger may have a proximal end, a distal end, and an elongate body. The conduit or connector may be operably attached to the open distal end of the barrel. The distal end of the barrel can include a variable inner diameter segment configured such that movement of the plunger to the variable inner diameter segment of the distal end of the barrel creates an audible and/or tactile feedback sensation to a user.

A drug injection device is disclosed. A drug injection device, according to the present invention, comprises: an injection unit which is provided with an ampoule accommodation portion for accommodating an ampoule that contains an injectable solution, and injects the injectable solution into a person being operated on; and an injection speed adjustment unit which is connected to the injection unit, applies pressure to the injectable solution, and adjusts the injection speed of the injectable solution, being injected into the body of the person being operated on, by selectively adjusting the speed of the pressure applied to the injectable solution, wherein the injection speed adjustment unit comprises: an injection unit attachment portion to which the ampoule accommodation portion is detachably attached; a pressurizing plunger which is connected to the ampoule accommodated in the ampoule accommodation portion and applies pressure to the injectable solution; and a pressurizing plunger up/down driving module which is provided on the same axis as the pressurizing plunger and drives the pressurizing plunger up or down.

A stopper includes a main body portion defining an open rearward end configured to receive the plunger rod, an engagement portion provided along an inner circumference of the main body portion configured to engage at least a top portion of the plunger rod, a closed front end forming a flexible roof, and a first perimetrical skirt extending around an outer circumference of the main body portion toward the closed front end of the main body portion. When fluid pressure is increased inside the syringe barrel during an injection, the flexible roof expands in a radial direction toward an inner wall of the syringe barrel, the first perimetrical skirt is forced against the inner wall of the syringe barrel, and an engagement between the plunger rod and the engagement portion forces the main body portion to expand in the radial direction toward the inner wall of the syringe barrel.

A stopper includes a main body portion defining an open rearward end configured to receive the plunger rod, an engagement portion provided along an inner circumference of the main body portion configured to engage at least a top portion of the plunger rod, a closed front end forming a flexible roof, and a first perimetrical skirt extending around an outer circumference of the main body portion toward the closed front end of the main body portion. When fluid pressure is increased inside the syringe barrel during an injection, the flexible roof expands in a radial direction toward an inner wall of the syringe barrel, the first perimetrical skirt is forced against the inner wall of the syringe barrel, and an engagement between the plunger rod and the engagement portion forces the main body portion to expand in the radial direction toward the inner wall of the syringe barrel.

An injector comprises a cylindrical barrel, a movable body housed in the barrel, and a plunger coming into separable contact with the movable body. The movable body includes a main body having an outer diameter smaller than an inner diameter of the barrel, a disk-shaped seal body disposed on the main body and including an outer circumferential end brought into close contact with an inner circumferential surface of the barrel, and at least one projecting portion projecting from the main body toward the inner circumferential surface of the barrel. A distance from a central axis of the movable body to a leading end of the at least one projecting portion is smaller than a half of an outer diameter of the seal body.

A stopper configured to slidably move within the hollow lumen of a syringe to facilitate movement of fluid within the syringe. The stopper includes a base and one or more capture members extending rearwardly from the base. The one or more capture members each include a beveled edge configured to interact with a piston of a fluid injection apparatus, wherein the one or more capture members are radially deflected upon rotation of the stopper relative to the piston to facilitate removal of the stopper from the piston. The stopper is configured for slidable movement within a body of a syringe and forms a fluid tight seal with an inner wall of the body of the syringe. Also disclosed is a plunger which includes the stopper.

The present invention provides a drug delivery device (1) comprising: a drug reservoir (20) comprising a reservoir body (21) extending along a reference axis and an elastomeric stopper (30) arranged in the reservoir body (21), the elastomeric stopper (30) comprising a stopper body (31) extending between a front stopper end (32) and a rear stopper end (34) and having a plurality of axially spaced apart circumferential ribs (33) for sealing interaction with an interior wall (22) of the reservoir body (21), and a plunger rod structure (10) for displacing the elastomeric stopper (30) relative to the interior wall (22), the plunger rod structure (10) extending along the reference axis and comprising a distal end face (12, 14) adapted to interface with the rear stopper end (34). The distal end face (12, 14) comprises a first force transferring portion (14) and a second force transferring portion (12), the first force transferring portion (14) axially leading the second force transferring portion (12) and being adapted to interact with a peripheral portion of the rear stopper end (34).

A plunging apparatus for a syringe is applied to connect with a driving assembly of an injection device and a medicine vial. The plunging apparatus has a pushing element connected with a connection element by a unidirectional check element. The rear end of the connection element is connected with a pushing rod. The front end of the pushing rod has an ejection element and a spring. A threaded collar is mounted around the pushing rod, and an injection rod is mounted in the pushing rod. The connection element is inserted into a rear opening of the medicine vial. Engagement hooks on the ejection element can be pressed by medicine vial. The spring forces the ejection element to move forward to push the pushing element to abut the piston. Accordingly, the medicine vial can be used immediately after being combined with the injection device without discharging air manually.

A pre-filled syringe includes a barrel with a medicament and a stopper within the barrel. The stopper has at least two adjacent sealing rings and a trim ring. The syringe has a head space distance between a distal-most surface of the stopper and the surface of the medicament. The head space (a) provides sufficient space to optimize reconstituting a drug suspension by shaking or agitating the drug suspension, and (b) minimizes frothing and/or clogging of the reconstituted drug suspension in the barrel. Also, a kit includes the syringe, a plunger, a syringe cap, and a needle assembly. Further, a method for stoppering the syringe includes determining the head space distance.