High-pressure microhydraulic actuator
US7384526B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 2004 |
| Grant date | Jun 10, 2008 |
| Priority date | — |
| Expiry date | Apr 4, 2026 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B19/006
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Electrokinetic (“EK”) pumps convert electric to mechanical work when an electric field exerts a body force on ions in the Debye layer of a fluid in a packed bed, which then viscously drags the fluid. Porous silica and polymer monoliths (2.5-mm O.D., and 6-mm to 10-mm length) having a narrow pore size distribution have been developed that are capable of large pressure gradients (250-500 psi/mm) when large electric fields (1000-1500 V/cm) are applied. Flowrates up to 200 μL/min and delivery pressures up to 1200 psi have been demonstrated. Forces up to 5 lb-force at 0.5 mm/s (12 mW) have been demonstrated with a battery-powered DC-DC converter. Hydraulic power of 17 mW (900 psi@ 180 uL/min) has been demonstrated with wall-powered high voltage supplies. The force and stroke delivered by an actuator utilizing an EK pump are shown to exceed the output of solenoids, stepper motors, and DC motors of similar size, despite the low thermodynamic efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.