Deflection compensated ink ejected printing apparatus
AssigneeRicoh Company, Ltd.
InventorMasanori Horike
Life of this patent
Estimating the term…
Abstract
Prior to printing, ink drops are ejected from an ink ejection head or nozzle (28) and an amount of deflection is sweepingly varied until the ink drops hit a target (57), thereby providing a reference which compensates for variations in an amount of charge of the ink drops, a mass of the ink drops, a deflection voltage and an ink drop velocity.
Claims18
An ink ejection apparatus including ink ejection means for ejecting and charging ink and deflecting the ink from an ejection axis in a direction in response to a deflection signal, characterized by comprising:
- target means spaced from the ejection axis in said direction;
- hit sensor means for sensing impingement of the ink on the target means and producing a hit signal in response thereto;
- and
- deflection sweep means for controlling the ink ejection means to sweepingly vary deflection of the ink until the hit sensor means produces the hit signal;
- the ink ejection means comprising nozzle means for ejecting ink in response to ejection pulses, charging means for charging the ink in response to charging pulses, charge sensor means for sensing when the ink has a predetermined charge and producing a phase set signal in response thereto and phase sweep means for sweepingly varying a phase between the ejection pulses and the charging pulses until the charge sensor means produces the phase set signal, the deflection sweep means and the phase sweep means being independent of each other.
An ink ejection apparatus including ink ejection means for ejecting and charging ink and deflecting the ink from an ejection axis in a direction in response to a deflection signal, characterized by comprising:
- target means spaced from the ejection axis in said direction;
- hit sensor means for sensing impingement of the ink on the target means and producing a hit signal in response thereto;
- and
- deflection sweep means for controlling the ink ejection means to sweepingly vary deflection of the ink until the hit sensor means produces the hit signal;
- the target means comprising a main target, the hit sensor means producing the hit signal in response to impingement of the ink on the main target, a first auxiliary target spaced from the main target in said direction and a second auxiliary target spaced from the main target opposite to said direction, the hit sensor means being further constructed to produce a first auxiliary hit signal in response to impingement of the ink on the first auxiliary target and a second auxiliary hit signal in response to impingement of the ink on the second auxiliary target, the deflection sweep means causing the ink ejection means to sweep the ink opposite to said direction in response to the first auxiliary hit signal and to sweep the ink in said direction in response to the second auxiliary hit signal;
- the first and second auxiliary targets comprising plates defining a slit therebetween, the main target being disposed behind the slit such that the ink must pass through the slit to reach the main target.
An ink ejection apparatus including ink ejection means for ejecting and charging ink and deflecting the ink from an ejection axis in a direction in response to a deflection signal, characterized by comprising:
- target means spaced from the ejection axis in said direction;
- hit sensor means for sensing impingement of the ink on the target means and producing a hit signal in response thereto;
- and
- deflection sweep means for controlling the ink ejection means to sweepingly vary deflection of the ink until the hit sensor means produces the hit signal;
- the target means comprising first and second plates defining a slit therebetween and a target disposed behind the slit such that the ink must pass through the slit to reach the target, the sensor means producing the hit signal in response to impingement of the ink on the target.
Dependencies are inferred from the claim text.