Droplet dispenser
AssigneeTTP Plc
InventorAdrian Woodward
Life of this patent
Estimating the term…
Abstract
A droplet dispenser comprises a chamber (3) with a fluid inlet valve (2) and a fluid outlet valve (4). The chamber (3) is arranged such that the volume of the chamber may be varied in use to cause fluid to be alternately drawn in to the chamber (3) through the inlet valve (2) then subsequently expelled from the chamber through the outlet valve (4) to dispense a droplet. The droplet dispenser is capable of dispensing from an open reservoir and one may change the dispensed drop volume simply and easily. The droplet dispenser can also handle liquids which are normally seen as difficult to dispense, such as cyanoacrylate adhesives.
Claims20
A droplet dispenser comprising a chamber with a fluid inlet valve and a fluid outlet valve, the chamber being arranged such that a chamber volume changes in use to cause fluid to be alternately drawn into the chamber through the fluid inlet valve then subsequently expelled from the chamber through the fluid outlet valve to dispense a droplet, the droplet dispenser further comprising:
- a control actuator arranged to apply a driving force to the droplet dispenser to dispense the droplet, wherein the control actuator comprises a solenoid, a pneumatic actuator, a piezo electric device, an electric motor or a manually actuated spring driven device;
- and
- a control system to vary a magnitude or a duration of the driving force applied by the control actuator to thereby vary a volume of the droplet that is dispensed by the droplet dispenser,
- wherein the volume of the droplet dispensed in a single dispensing is proportional to at least one of the magnitude or the duration of the driving force, and
- wherein the chamber includes walls that comprise elastomeric material such that the volume of the chamber changes by elastic deformation of the elastomeric material.
A droplet dispensing system comprising:
- a control system;
- an actuator electrically controlled by the control system to apply a driving force to a support element;
- a fluid reservoir containing a fluid;
- a chamber functionally connected to the fluid reservoir,
- wherein the chamber is functionally attached to the support element, the chamber comprising:
- elastomeric walls arranged in a tubular structure,
- a fluid inlet valve, and
- a fluid outlet valve,
- wherein, in use, the actuator applies the driving force to the support element to increase a distance between the fluid inlet valve and the fluid outlet valve, thereby increasing a chamber volume and causing the fluid in the fluid reservoir to be drawn into the chamber through the fluid inlet valve while the fluid outlet valve remains closed,
- wherein, after the fluid is drawn into the chamber, the actuator applies the driving force to the support element to decrease the distance between the fluid inlet valve and the fluid outlet valve, thereby decreasing the chamber volume and causing at least some of the fluid within the chamber to be dispensed from the chamber through the fluid outlet valve as an individual droplet while the fluid inlet valve remains closed,
- wherein a volume of the individual droplet is proportional to a magnitude of the driving force applied by the actuator to the chamber, and
- wherein the control system is configured to vary a drive voltage applied to said actuator to vary the magnitude of the driving force to control the volume of the individual droplet.
Dependencies are inferred from the claim text.