Pulsation control having pulse width modulating driving circuit
US5584262A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 2, 1995 |
| Grant date | Dec 17, 1996 |
| Priority date | — |
| Expiry date | Mar 2, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01J5/14
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A milking machine pulsation control includes a microcontroller which generates a pulse width modulated drive signal to control current to pulsator valves, with a high current for pull-in and a lower current for holding. The pulse width modulated drive signal is based on line voltage and compensated for supply frequency. A zero crossing circuit controls internal switching at zero volts to reduce noise. A watchdog circuit resets the computer in the event of latch-up as a result of circuit transients. An over-current shut-down circuit the switches that operate the valve. Synchronism is provided with other pulsation controls. Operator input switches and visual displays are multiplexed to the microcontroller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.