Injection molding mechanism for forming a monolithic tubular pipette

An injection molding mechanism for forming a monolithic tubular pipette with a tapered tip integrally formed therewith comprising:

• a mold with a prolate cavity having a tapered end;
• an elongated core having a tapered end for residing in said cavity to establish a tubular space between the mold and said core for creating the pipette;
• a rod extending from the tip of said core to the mold for establishing a hole in the tip of the pipette;
• an upper pair of movable locking pins and a lower pair of movable locking pins for preventing lateral movement of said core during the injection cycle;
• drive means for selectively extending said pins to engage said core for locking, and for retracting said pins into a recessed position in the wall of said cavity;
• means for injecting a resin into said cavity about said core;
• and
• control means for sequentially operating said drive means to extend said upper and lower pins, operating said means for injecting to inject resin into said cavity, and operating said drive means to retract first said upper pins and second said lower pins as said resin fills the space proximate each respective pair of pins.