US 8,237,324 B2 · Bistable electroactive polymers

Abstract

A bistable electroactive polymer transducer is provided for electrically actuated deformation of rigid electroactive polymer members. The polymers have glass transition temperatures (Tg) above ambient conditions and turn into rubbery elastomers above Tg and have high dielectric breakdown strength in the rubbery state. They can be electrically deformed to various rigid shapes with maximum strain greater than 100% and as high as 400%. The actuation is made bistable by cooling below Tg to preserve the deformation. The dielectric actuation mechanism includes a pair of compliant electrodes in contact with a dielectric elastomer which deforms when a voltage bias is applied between the pair of electrodes. In some of the configurations, the dielectric elastomer is also a shape memory polymer. The deformations of such bistable electroactive polymers can be repeated rapidly for numerous cycles.

Claims35

Dependent claims

A bistable transducer, comprising:

a plurality of polymer members;
and
at least two electrodes joined to said polymer members configured to produce an electric field;
wherein said polymer softens with an increase in temperature and deforms in response to a change in an applied electric field between the electrodes;
and
wherein said polymer member retains a deformed shape with a reduction in temperature below a transition temperature.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

12/635,674Filed 10 Dec 2009 · us provisional application

Priority

10 Dec 2008

Published

US 2010/0171393 A18 Jul 2010

Granted

7 Aug 2012

Term ends

Not estimatedThe source records don’t support an estimate.

Classification14 codes

G06F 3/016
Input arrangements or combined input and output arrangements for interaction between user and computer: input arrangements with force or tactile…
F03G 7/0121
Electro-chemical actuators: electroactive polymers
F03G 7/029
Mechanical-power-producing mechanisms, not otherwise provided for or using energy sources not otherwise provided for: characterised by the…
F03G 7/0612
Characterised by the actuating element: using polymers

Bistable electroactive polymers

Life of this patent

Bistable electroactive polymers

Life of this patent

Abstract

Claims35