Method and apparatus for lubricating stoppers for syringe barrels

#The field of the invention relates to methods and apparatus for assembling syringes and other such medical devices which include a stopper and plunger assembly for drawing or ejecting fluids.

#Syringes are generally comprised of a cylindrical barrel, a cannula secured to one end of the barrel, a stopper within the barrel, and a plunger secured to the stopper for moving it within the barrel. The barrel, plunger and stopper are often molded from various thermoplastic materials. The cannula is usually made from metal such as stainless steel.

#The manufacture of syringes typically involves the use of a machine for assembling the barrel/cannula assembly with the other molded components. Barrel/cannula assemblies, complete with shields for protecting the cannulas, are loaded into the machine while plungers and stoppers are loaded into separate machine feed hoppers. The stoppers flow to a feed bowl or the like from where they are fed to a track and then to a dial. A dial is a disk shaped metal (or non-metal) article having slots for retaining selected items. In the meantime, the plungers move along a track to another dial adjacent to the stopper dial but at a different height within the machine. The plungers and stopper held by the respective dials are moved into engagement with each other and joined. This subassembly is then transferred to another dial from where it is inserted within the syringe barrel.

#FIG. 1 is a partially sectioned side elevation view of an apparatus for lubricating stoppers within a syringe assembly machine;

#FIG. 2 is a bottom plan view of a lubricating wheel as shown in FIG. 1;

#FIG. 3 is a side elevation view thereof; and

#A lubricating apparatus 10 for applying a lubricant such as silicone oil 12 to a stopper 14 is shown in FIG. 1. The apparatus is contained within a machine 16 for assembling syringes from prefabricated components, the machine being diagrammatically illustrated in FIG. 4. The apparatus 10 is positioned after the assembly equipment 18 which joins the stoppers to plungers, but before the assembly equipment 20 which inserts the plunger/stopper subassemblies 22 into syringe barrels.

#As shown in FIG. 1, a plunger/stopper subassembly 22 is transported in the vertical position to the apparatus by a dial 24. The stopper end faces downwardly when positioned within the apparatus 10.

#The apparatus 10 is mounted to a support 26 within the assembly machine 16. It includes a body portion 28, a main shaft 30, a short shaft 32, and a pair of lubricating wheels 34 mounted to the respective shafts. A gearmotor 36 is provided for driving the two shafts at the same rotational velocity when the wheels, such as in this embodiment, are of the same diameter.