Patent ID: 9527320
Filing Date: 2016-12-27
CPC Classification: B41J

Claim Text:
1. A print head protection system for use in connection with an inkjet printer having an inkjet print head, the print head being adapted for elevating, and a media sheet having a lead edge and a trail edge, the media sheet moving in a process direction along a process path, the print head protection system comprising: a media transport for conveying the media sheet along the process path, and for holding the media sheet generally flat; at least one acoustic sensor disposed beneath the media transport and upstream of the print head, the acoustic sensor being adapted to acoustically measure a combined thickness of the media transport and the media sheet without contacting the media transport or media sheet; an analyzer operatively connected to the acoustic sensor for analyzing the combined thickness of the media transport and the media sheet so as to detect if the media sheet is in contact with the media transport, the analyzer being adapted to create an error signal when the media sheet is not in contact with the media transport; and a mitigation control operative to mitigate print head damage in response to the signal.