Printing assembly having liftable carriage with constrained rotational movement

摘要

A printer assembly includes a housing having a pair of opposite first and second sidewalls, the first sidewall having a vertical guide slot; a shaft rotatably mounted between the sidewalls; pinions fixedly mounted at either end of the shaft; a print bar carriage slidably received within the housing; and a drive motor for rotating the shaft and lifting the print bar carriage. The print bar carriage includes: a chassis; first and second racks engaged with respective pinions to define a rack-and-pinion lift mechanism; first bearings rotatably mounted at a first side of the chassis, each first bearing being received in the guide slot; and a printhead supported by the chassis. During sliding movement of the print bar carriage, the first bearings travel within the guide slot and bear against opposite guide surfaces to constrain rotational movement of the print bar carriage.

主权项

1. A printer assembly comprising:
a housing comprising a pair of opposite first and second sidewalls extending along a nominal x-axis, the first sidewall having a guide slot extending along a z-axis, the guide slot being defined between opposite first bearing surfaces; a shaft rotatably mounted between the sidewalls, the shaft extending along a y-axis; first and second pinions fixedly mounted at either end of the shaft for rotation therewith; a print bar carriage slidably received within the housing, the print bar carriage comprising:
a chassis;first and second parallel racks fixed to the chassis, each rack being engaged with a respective pinion to define a rack-and-pinion lift mechanism;a set of first bearings rotatably mounted at a first side of the chassis, each first bearing being received in the guide slot; anda printhead supported by the chassis; and a drive motor operatively connected to the shaft for rotating the shaft and thereby lifting the print bar carriage relative to the housing along the z-axis via the rack-and-pinion lift mechanism,wherein, during sliding movement of the print bar carriage, the set of first bearings travels within the guide slot and bear against the first guide surfaces to constrain rotational movement of the print bar carriage.