Abstract: Example embodiments provide a voice coil speaker that may comprise a speaker frame and a diaphragm connected to the speaker frame and configured to be capable of axial movement. A heat conducting coil former may be connected to the diaphragm. A pole piece and a back plate may form an annular gap and conduct magnetic flux from an axially polarized permanent magnet in a complete loop that includes the annular gap. A voice coil may be wound on the heat conducting coil former and residing in the annular gap, the magnetic flux passing through the voice coil in the radial direction, such that the voice coil produces an axial force to cause the diaphragm to produce sound. A thermal bridge may be configured to conduct heat from the heat conducting coil former to the back plate.

Abstract: Example embodiments provide a voice coil apparatus that may comprise corner posts, a voice coil wound directly on to the corner posts, the coil forming straight sides between the corner posts due to winding tension, and a center flux return having straight sides and having a continuous plated layer of electrically conductive material, the center flux return being made of a ferromagnetic material. The voice coil apparatus may further comprise rubber mounts at corners of the center flux return and supporting the corner posts, and configured to provide high lateral compression stiffness and low axial shear stiffness in order to facilitate axial movement of the voice coil. In example embodiments, the voice coil lacks a coil former. The rubber mounts and the corner posts establish a uniform offset. The continuous plated layer serves as a shorted turn.

Abstract: A peristaltic pump with three coaxial cylindrical components; a high-modulus rod contained within a piezoelectric tube, which in turn is contained within a cylindrical pressure casing, which may the casing of a hydraulic cylinder. The casing is filled with ERF. The piezoelectric tube has a plurality of electrode bands attached to its outer surface and is coated on its interior with an electrically conductive material. The electrodes are voltage-activated to cause certain portions of the tube to expand and others to contract, resulting in peristaltic action. The applied voltage also causes the ERF to form a gel state both inside and outside of the piezoelectric tube.