Flow rate control system
US4827280A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 1988 |
| Grant date | May 2, 1989 |
| Priority date | — |
| Expiry date | Aug 9, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D7/0635
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A flow rate control system is disclosed for measurement of ink flow through an ink jet system. The flow rate control system receives an error signal indicative of deviation of flow rate from a set value. The system includes proportional (P), integral (I) and derivative (D) control to generate a control signal based on the magnitude and sign of the error signal. The control signal is used to control the on-time of an ink make-up valve which adds make-up ink to the system as ink is needed to maintain satisfactory operation. In a preferred embodiment, the PID controller has noise reduction capability through the use of clippers and low pass filters. In addition, conditional summation may be employed to minimize "hunting" at low error signal levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.