Position control for plunge mechanism

A cartridge engaging assembly comprising:

• a plunge mechanism mounted to the cartridge engaging assembly, said plunge mechanism being moveable between a retracted position and an extended position;
• a reference mark provided on said plunge mechanism so that said reference mark moves with said plunge mechanism;
• a detector mounted to the cartridge engaging assembly, said detector comprising a bar code reader, said bar code reader:
• i) sensing a size of said reference mark and producing an output signal related thereto, and ii) reading a bar code provided on a cartridge positioned adjacent the cartridge engaging assembly;
• and
• a control system operatively associated with said detector and responsive to the output signal produced thereby, said control system also being operatively associated with said plunge mechanism, said control system regulating the position of said plunge mechanism based on the output signal.

A cartridge engaging assembly comprising:

• a plunge mechanism mounted to the cartridge engaging assembly, said plunge mechanism being moveable between a retracted position and an extended position;
• a reference mark provided on said plunge mechanism so that said reference mark moves with said plunge mechanism;
• a detector mounted to the cartridge engaging assembly, said detector comprising a bar code reader, said bar code reader:
• i) sensing an image of said reference mark and producing an output signal related thereto when the plunge mechanism is in said extended position, and ii) reading a bar code provided on a cartridge positioned adiacent the cartridge engaging assembly when the plunge mechanism is in said retracted position;
• and
• a control system operatively associated with said detector and responsive to the output signal produced thereby, said control system also being operatively associated with said plunge mechanism, said control system regulating the position of said plunge mechanism based on the output signal.

A cartridge engaging assembly, comprising:

• plunge means mounted to the cartridge engaging assembly, said plunge means moving to an extended position to engage a data cartridge and moving to a retracted position to draw the data cartridge into the cartridge engaging assembly;
• reference means provided on said plunge means, said reference means moving with said plunge means;
• means for detecting a size of said reference means;
• and
• means for regulating a position of said plunge means based on the detected size of said reference means.