Print substance level measurements
AssigneeHewlett-Packard Development Company, L.P.
InventorsKenneth Williams, Tobias Martin
Life of this patent
Estimating the term…
Abstract
Methods of determining a level of a print substance in a print substance reservoir are disclosed. A reference capacitance of a reference sensor is measured. The reference capacitance is representative of one of a full print substance reservoir and an empty print substance reservoir. A level capacitance of a level sensor is measured. A correlation between the reference sensor and the level sensor is applied to the measured reference capacitance to determine an adjusted reference capacitance. A fill level ratio is determined based on the measured level capacitance and the adjusted reference capacitance.
Claims15
A method of determining a level of a print substance in a print substance reservoir, comprising:
- measuring a reference capacitance of a reference sensor, the reference capacitance representative of one of a full print substance reservoir and an empty print substance reservoir;
- measuring a level capacitance of a level sensor;
- applying a correlation between the reference sensor and the level sensor to the measured reference capacitance to determine an adjusted reference capacitance;
- and
- determining a fill level ratio based on the measured level capacitance and the adjusted reference capacitance.
A printing device, comprising:
- a print substance container having a print substance reservoir and a sensor system having a level sensor and a reference sensor, the level sensor operably coupled to the print substance reservoir;
- and
- a controller operably coupled to the sensor system, the controller to:
- measure a reference capacitance of a reference sensor, the reference capacitance representative of one of a full print substance reservoir and an empty print substance reservoir;
- measure a level capacitance of a level sensor;
- apply a correlation between the reference sensor and the level sensor to the measured reference capacitance to determine an adjusted reference capacitance;
- and
- determine a fill level ratio based on the measured level capacitance and the adjusted reference capacitance.
A non-transitory computer readable medium to store computer executable instructions to control a processor to:
- measure a reference capacitance of a reference sensor, the reference capacitance representative of one of a full print substance reservoir and an empty print substance reservoir;
- measure a level capacitance of a level sensor;
- apply a correlation between the reference sensor and the level sensor to the measured reference capacitance to determine an adjusted reference capacitance;
- and
- determine a fill level ratio based on the measured level capacitance and the adjusted reference capacitance.
Dependencies are inferred from the claim text.