Patent ID: 9671722
Date: 2017-06-06
CPC Classifications: G01L,G01N,G03G

Claim:
1. A measurement apparatus for determining a measure for the solid content of a liquid toner, said liquid toner comprising a carrier liquid with marking particles, and said solid content being the ratio of the mass of the marking particles divided by the mass of the liquid toner, said measurement apparatus comprising: a measurement space for receiving liquid toner, said measurement space comprising at least one hydrostatic pressure sensor configured and arranged for measuring data representative for the hydrostatic pressure caused by the liquid toner at least one predetermined position in the measurement space; and a controller configured for receiving the measured data and for determining a measure for the solid content of the liquid toner based on the received data; further comprising a liquid toner reservoir storing the liquid toner; said liquid toner reservoir having an outlet line for discharging liquid toner into said measurement space and a return line for receiving liquid toner from said measurement space; wherein the outlet line or the return line includes a pump, and wherein the controller is configured for controlling the pump such that normal pump operation is stopped or such that pump power is reduced while measuring data with the at least one hydrostatic pressure sensor.