With the Type 515 plunger rod insertion machine with backstop assembly, syringes are manually fed into an infeed chute, which transfers them to the main transport system. At the heart of the machine is an automated transport starwheel, which moves the product through four different stations, helping assemble up to 60 syringes per minute. Plunger rods are supplied from a vibratory sorting bowl and travel down a feed track to the insertion station. A pneumatically actuated gripper assembly picks up a plunger rod from the end of the vibratory track and leverages a two-axis robotic arm to thread it into a syringe. At the second station, backstops are carefully placed on the flange of each syringe. The third and fourth station check for plunger rod and backstop presence. The key differentiator of the machine is its ability to monitor the rotational torque applied to the syringe. This action, combined with plunger rod position, can control analog to the syringe rotational position during the threading process. The advanced technology used on this machine allows for tight control of all process parameters, ensuring consistent product quality, compensating for component imperfections and preventing excessive plunger movement during the process. The z-axis and rotational servo controls allow precise adjustment of the downward feed rate based on the pitch of the thread on the end of the rod tip and the rotary position of the syringe. The feed rate is always slightly less than the pitch of the rod thread. If there is a rotary thread start misalignment, the syringe will be lifted slightly during the insertion process. When the plunger and the rod are fully assembled, the servomotor spinning the disk detects an increase in torque and stops both the rotational and z-axis motors simultaneously. In the event the torque limiting value is not reached (due to a defective product such as excessive silicone in the syringe, undersize stoppers or defective thread on the end of rod), the process aborts. This potentially defective part is tagged and automatically discharged to the reject station. The z-axis servo motion is fully programmable, allowing for precise control over plunger rod torque, position and insertion speed. This insertion torque and position control makes it possible to tightly synchronize the downward feed rate to the rotational rate (rpm) of the rotating syringe. The machine can handle syringes with a diameter ranging from 16 to 52 mm and heights from 30 to 130 mm, and allows for speeds of up to 60 assemblies per minute.
Bausch Advanced Technologies, Inc., Clinton, CT 06413. www.bausch-group.com or call 860-669-7380
INTERPHEX 2012 Booth No. 3063