Synchronously operable electrical current switching apparatus having

Abstract

A synchronously operable, piezoelectrically actuated electrical current switching apparatus is provided which has increased separation between the switching contacts when they are in the open position, and increased contact closing force when they are in the closed position. The apparatus includes a pair of spaced-apart, opposing multimorph piezoelectric benders and at least one pair of electrical current switching contacts mounted on the opposing surfaces of the pair of benders, with one contact being mounted on each of the surfaces. The benders are disposed so that they bend toward each other in response to a first electrical signal, moving the contacts to a closed position. In response to a second electrical signal, the benders bend away from each other and move the contacts to an open position. In this manner, the distance achievable between the contacts in the open position is greater than the displacement available from either of the benders alone. Preferably, the benders are also disposed so that the distance between the contacts, in the absence of any applied electrical signal, is less than the sum of the displacements available from the two benders. The principles of the invention may be extended to a set of three piezoelectric benders, configured similarly to the manner described above, so that a three-position switch is provided.