Patent · US Expired

Variable ratio dispensing apparatus

US4286732A · kind A · utility

11Cited by
8References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 16, 1979
Grant dateSep 1, 1981
Priority date
Expiry dateApr 16, 1999

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01F35/8822
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Dispensing apparatus with a pain of fluid dispensing cylinders each having a piston driven through a separate differential transmission with two inputs. One of the inputs of both transmissions is driven by a first electric motor. The other inputs are connected to counterrotating output shafts of a gear box driven by a variable speed second electric motor to introduce unlike inputs into the differential transmissions so that the ratio of fluid dispensed by the cylinders is varied by operation of the second motor in different directions and at different speeds. During the return stroke of the pistons the second motor is operated at a rate higher than its rate during the dispensing stroke so that any difference in the length of the dispensing stroke of the pistons is reduced to zero before the pistons home, whereupon the second motor is de-actuated and the first motor alone homes the pistons to prevent the pistons from getting out of phase.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.