Method and apparatus for using ultrasonic energy for moving microminiature elements

A micromotor device for moving a micro-miniature element along a predetermined path comprising:

• a substrate;
• a membrane supported by said substrate having an upper layer with a planar upper surface for supporting the element to be moved and a lower layer of a piezoelectric material with a lower surface;
• ultrasonic generator means attached to one said membrane surface;
• and
• means for supplying electrical power to said ultrasonic generator means to produce ultrasonic energy and thereby cause a flexural wave action in said membrane;
• wherein said micro-miniature element comprises a disk rotatably attached to said device, said ultrasonic generator means being aligned on said membrane along a line spaced radially from the center of said disk, whereby a flexural wave force is produced to act tangentailly on said disk and cause it to rotate.

A micromotor device for moving a micro-miniature element along a predetermined path comprising:

• a substrate;
• a membrane supported by said substrate having an upper layer with a planar upper surface for supporting the element to be moved and a lower layer of a piezoelectric material with a lower surface;
• ultrasonic generator means attached to one said membrane surface;
• and
• means for supplying electrical power to said ultrasonic generator means to produce ultrasonic energy and thereby cause a flexural wave action in said membrane;
• wherein said membrane has a circular conical recess with a thickness that increases radially from the center of said recess, and a pair of said ultrasonic generator means spaced diametrically apart on the inner surface of said recess and on opposite sides of its center so that a flexural wave action extending radially from said center is produced.

A micromotor device for moving a micro-miniature element along a predetermined path comprising:

• a substrate;
• a membrane supported by said substrate having an upper layer with a planar upper surface for supporting the element to be moved and a lower layer of a piezoelectric material with a lower surface;
• ultrasonic generator means attached to one said membrane surface;
• and
• means for supplying electrical power to said ultrasonic generator means to produce ultrasonic energy and thereby cause a flexural wave action in said membrane;
• wherein said membrane has a central opening and said ultrasonic generator means comprise a pair of arcuate shaped planar transducers spaced radially from opposite sides of said membrane opening and adapted to produce a flexural wave action in said membrane that moves radially towards or away from said opening.

A micromotor device for moving a micro-miniature element along a predetermined path comprising:

• a substrate;
• a membrane supported by said substrate having an upper layer with a planar upper surface for supporting the element to be moved and a lower layer of a piezoelectric material with a lower surface;
• ultrasonic generator means attached to one said membrane surface;
• and
• means for supplying electrical power to said ultrasonic generator means to produce ultrasonic energy and thereby cause a flexural wave action in said membrane;
• wherein said ultrasonic generator means are provided in two pairs of spaced apart planar transducers on one side of said membrane, said transducer pairs being aligned along separate straight lines that intersect at right angles, whereby said micro-miniature element is movable in both "x" and "y" directions which are at right angles to each other on the membrane surface.

A micromotor device for controlling the movement of a micro-miniature element along a predetermined path comprising:

• a substrate;
• a membrane supported by said substrate having an upper planar surface and a bottom surface;
• a micro-miniature element having a region of optical transparency forming a second generating transducer means and supported on said upper planar surface;
• a first ultrasonic generating transducer means attached to the upper surface of said membrane;
• means for supplying electrical power to said first transducer means to produce a flexural wave action in said membrane and thus movement of said micro-miniature element;
• a linear position sensor including a fixed receiving transducer on said upper membrane surface, means for illuminating said micro-miniature element and circuit means for generating a position feeedback signal from said second generating transducer means to said fixed receiving transducer;
• and
• means for supplying said feedback signal to said electrical power means to control precisely the position of said micro-miniature element on said upper planar surface.

A method for moving a micro-miniature element along a predetermined path over a surface comprising the steps of:

• providing a substrate structure with a multi-layer membrane section having a smooth surface for supporting the element to be moved;
• generating ultrasonic plate waves in said membrane section;
• and
• controlling the amplitude and direction of such waves to cause movement of said element along said membrane surface in a desired path.

A method for moving a micro-miniature element along a predetermined path over a surface comprising the steps of:

• providing a substrate structure with a multi-layer membrane section having a smooth surface for supporting the element to be moved;
• generating ultrasonic plate waves in said membrane section;
• controlling the amplitude and direction of such waves to cause movement of said element along said membrane surface in a desired path;
• wherein said micro-miniature element has relatively movable components, and including the step of controlling the frequency of said waves on said membrane section so as to cause a dithering of said movable components to reduce friction as they move relative to each other.

A method for moving a micro-miniature element along a predetermined path over a surface comprising the steps of:

• providing a substrate structure with a multi-layer membrane section having a smooth surface for supporting the element to be moved;
• generating ultrasonic plate waves in said membrane section;
• controlling the amplitude and direction of such waves to cause movement of said element along said membrane surface in a desired path;
• including the step of providing a membrane with a circular frusto-conical recess with a pair of ultrasonic generators spaced radially from the center of said recess, and causing the speed of waves produced by said generators to increase with distance from said recess center so as to produce waves whose energy propagates in a circumferential direction.