Abstract: A method for accelerating or decelerating a moveable body which body is moved by urging a piezoelectric micromotor to the body in a first direction so that a contact region of the piezoelectric motor is pressed to the body and exciting vibrations in the piezoelectric micromotor at the contact region in the first direction and in a second direction along a direction of motion of the body, said vibrations having a first amplitude in the first direction and a second amplitude in the second direction, the method comprising: a) for acceleration, gradually changing a ratio between the second amplitude relative to the first amplitude from substantially zero to a desired non-zero value; or b) for deceleration, gradually changing the ratio between the second amplitude relative to the first amplitude from a non-zero value to substantially zero.

Abstract: A piezoelectric vibrator comprising: a thin rectangular piezoelectric plate formed of a material having a Young's modulus having two short edge surfaces and two long edge surfaces and two large planar face surfaces which plate has transverse resonant vibration modes parallel to its short edges and longitudinal resonant vibration modes parallel to its long edges and is formed with at least one cavity; and at least one electrode on each of the planar surfaces that is electrifiable to excite at least one vibration mode of the plate, wherein the at least one cavity is not filled with a material having a Young's modulus substantially equal to the Young's modulus of the material from which the plate is formed, such that the presence of the at least one cavity shifts a resonant frequency of at least one vibration mode of the plate with respect to the resonant frequency that characterizes the at least one vibration mode in the absence of the at least one cavity.

Abstract: A method for accelerating or decelerating a moveable body which body is moved by urging a piezoelectric micromotor to the body in a first direction so that a contact region of the piezoelectric motor is pressed to the body and exciting vibrations in the piezoelectric micromotor at the contact region in the first direction and in a second direction along a direction of motion of the body, said vibrations having a first amplitude in the first direction and a second amplitude in the second direction, the method comprising: a) for acceleration, gradually changing a ratio between the second amplitude relative to the first amplitude from substantially zero to a desired non-zero value; or b) for deceleration, gradually changing the ratio between the second amplitude relative to the first amplitude from a non-zero value to substantially zero.

Abstract: A piezoelectric micromotor for moving a moveable element comprising: a vibrator in the shape of a rectangular parallelepiped formed from a plurality of thin layers of piezoelectric material having first and second identical relatively large rectangular face surfaces defined by long and short edge surfaces wherein the layers are aligned one on top of the other and have their face surfaces bonded together; electrodes on surfaces of the layers; a contact region located on one or more edge surfaces of the layers, urged against the body; and at least one electrical power supply that electrifies electrodes to excite vibrations in the vibrator and thereby in the contact region that impart motion to the body.

Abstract: A piezoelectric vibrator comprising: a thin rectangular piezoelectric plate formed of a material having a Young's modulus having two short edge surfaces and two long edge surfaces and two large planar face surfaces which plate has transverse resonant vibration modes parallel to its short edges and longitudinal resonant vibration modes parallel to its long edges and is formed with at least one cavity; and at least one electrode on each of the planar surfaces that is electrifiable to excite at least one vibration mode of the plate, wherein the at least one cavity is not filled with a material having a Young's modulus substantially equal to the Young's modulus of the material from which the plate is formed, such that the presence of the at least one cavity shifts a resonant frequency of at least one vibration mode of the plate with respect to the resonant frequency that characterizes the at least one vibration mode in the absence of the at least one cavity.

Abstract: A method is provided for exciting vibrations in a piezoelectric motor having a plurality of electrode sets, each set comprising at least one first electrode and at least one second electrode between which AC voltages are applied to excite vibrations in the piezoelectric motor, the method comprising: coupling an AC power source to the at least one first electrode and at least one second electrode of a first electrode set; electrically connecting the at least one first electrode to the at least one second electrode of a second set of electrodes with a non-zero impedance that is substantially less than an impedance between them resulting from stray capacitive coupling; and energizing the power source to apply an AC voltage difference between the at least one first electrode and at least one second electrode of the first set of electrodes to excite the vibrations.

Abstract: Apparatus for providing linear motion to a generally flat flexible material, comprising: (a) at least one piezoelectric ceramic motor situated on a first side of the flat flexible material and having a contact surface which contacts the flat flexible material and which imparts said linear motion; and (b) a bearing surface situated on a second side of the flat flexible material opposite said contact surface.

Abstract: A latch for locking a drive arm of a disk drive in a parking position comprising: a latch stop having a baffle moveable between an open position and a closed position; and a piezoelectric motor operable to move the baffle between the open and closed positions. When the drive arm is in the parking position it engages the baffle and is prevented from leaving the parking position when the baffle is in the closed position and is not prevented from leaving the parking position when the baffle is in the open position.

Abstract: A multidirectional motor system for transmitting motion to a moveable element in at least two directions that are not collinear comprising a first motor that transmits motion to the moveable element along a direction determined by the orientation of the first motor and a second motor operable to change the orientation of said first motor.

Abstract: An actuator system for activating a latch needle, which latch needle has a shaft, comprising: a flat planar extension of said shaft having first and second parallel planar surfaces; at least one piezoelectric micromotor having a first surface region for transmitting motion to a moveable element, which first surface region is resiliently pressed to said first surface and at least one additional piezoelectric motor having a second surface region for transmitting motion to a moveable element which second surface region is resiliently pressed to said second surface; and wherein vibratory motions of said first and second surface regions apply forces to said flat extension that cause motion in said latch needle.

Abstract: An actuator system for activating a latch needle, which latch needle has a shaft, comprising: a flat planar extension of said shaft having first and second parallel planar surfaces; at least one piezoelectric micromotor having a first surface region for transmitting motion to a moveable element, which first surface region is resiliently pressed to said first surface and at least one additional piezoelectric motor having a second surface region for transmitting motion to a moveable element which second surface region is resiliently pressed to said second surface; and wherein vibratory motions of said first and second surface regions apply forces to said flat extension that cause motion in said latch needle.

Abstract: The present invention provides a method for rapidly switching selector feet (52) between activate and deactivate selection positions by friction coupling them to vibratory piezoelectric motors (58) and a fast selector (50) for a knitting machine comprising selector feet friction coupled to piezoelectric motors.

Abstract: An optical position monitor for determining the position of a latch needle (104) in a knitting machine is provided that comprises: at least one fiducial (102) at a known fixed cation on the body of the latch needle; a fiducial imager that produces at least one optical image (262) of the at least one fiducial on at least one light sensitive surface (260) wherein the at least one optical image changes with changes in position of said at least one fiducial; and a controller that receives at least one signal responsive to the changes in the at least one image and uses the at least one signal to determine the position of the at least one fiducial (102) and thereby of the latch needle (104).

Abstract: An even plurality of piezoelectric motor units operating directly on an element to be vertically translated, such as a car window, is disclosed. Each pair of piezoelectric motor units are located along an horizontal line on opposing sides of the element. The piezoelectric motors are preferably, asynchronously operated. An activation system for providing alternating current (AC) voltage to each of the piezoelectric motor units and converting direct current voltage to a sinusoidal square wave, is also included.