Piezoelectric motors including a stiffener layer

Patent metadata

Field	Value
Publication number	US-10002628-B2
Application number	US-201715657724-A
Country	US
Kind code	B2
Filing date	Jul 24, 2017
Priority date	Dec 16, 2014
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

Various embodiments concern a gimbaled flexure having a dual stage actuation structure. The flexure comprises a gimbal on which a motor is mounted. The motor comprises a first terminal, one or more layers of piezoelectric material, and a metal stiffener disposed directly on the first terminal. The stiffener comprises a layer of metal defining a majority of a top side of the motor. The first terminal can be gold sputtered on the piezoelectric material while the stiffener can be nickel plated on the gold. The stiffener can cause the motor, and the flexure on which it is mounted, to curl upon electrical activation of the motor.

First claim

The following is claimed:

1. A motor, comprising:
one or more piezoelectric material actuator layers defining first and second major broad sides;
a first conductive layer on the first major broad side, the first conductive layer has a thickness and an elastic modulus and is configured to connect with a first terminal pad;
a second conductive layer on the second major broad side, the second conductive layer has a thickness and an elastic modulus and is configured to connect with a second terminal pad; and
a stiffener layer on and in contact with one of the first and second conductive layers, the stiffener layer formed on one of the first and second major broad sides, the stiffener having one or more sides recessed from a corresponding side of the one or more piezoelectric material actuator layers.

2. The motor of claim 1 , wherein the first conductive layer and the second conductive layer is a first metal and the stiffener layer is a second metal.

3. The motor of claim 2 wherein:
the first metal includes copper; and
the second metal includes nickel.

4. The motor of claim 1 , wherein the stiffener layer has a thickness that is at least five times thicker than at least one of the thickness of the first conductive layer and the thickness of the second conductive layer.

5. The motor of claim 1 , wherein the thickness of the first conductive layer and the thickness of the second conductive layer are equal.

6. The motor of claim 1 , wherein the stiffener layer is a plated metal layer.

7. The motor of claim 1 , has an elastic modulus that is higher than the elastic modulus of the first metal, and has a thickness that is greater than the thicknesses of the first and second conductive layers.

8. The motor of claim 1 , wherein the first conductive layer is configured to connect with the first terminal pad through a first connector.

9. The motor of claim 8 , wherein the second conductive layer is configured to connect with the second terminal pad through a second connector.

10. The motor of claim 1 , wherein the first conductor layer includes a first terminal on a first end side of the one or more piezoelectric material actuator layers and the second conductor layer includes a second terminal on a second end side of the one or more piezoelectric material actuator layers, the first end side and the second end side are on opposite ends of the piezoelectric material.

11. The motor of claim 1 , wherein the first terminal pad and the second terminal pad are formed on a flexure.

12. The motor of claim 1 , wherein the first conductor layer includes a first terminal on a first end side of the one or more piezoelectric material and the second conductor layer includes a second terminal on a second end side of the one or more piezoelectric material, the first end side and the second end side are on opposite ends of the piezoelectric material.

13. A suspension structure comprising:
a flexure including:
a first spring arm and a second spring arm,
a tongue having a slider mounting region supported by and located between the first spring arm and the second spring arm, and
a plurality of electrical traces including a first trace and a second trace; and

a motor including:
one or more piezoelectric material actuator layers define a first major broad side and a second major broad side,
a first conductive layer on the first major broad side, the first conductive layer has a thickness and an elastic modulus and is configured to connect with a first terminal pad,
a second conductive layer on the second major broad side, the second conductive layer has a thickness and an elastic modulus and is configured to connect with a second terminal pad, and
a stiffener layer on and in contact with one of the first and second conductive layers, the stiffener layer formed on one of the first and second major broad sides, the stiffener having one or more sides recessed from a corresponding side of the one or more piezoelectric material actuator layers.

14. The suspension structure of claim 13 , wherein:
the one or more piezoelectric material actuator layers define a first end and a second end;
the first end is coupled to the first spring arm; and
the second end is coupled to the second spring arm.

15. The suspension structure of claim 13 and further including:
a first connector mounting the first end of the one or more piezoelectric material actuator layers to the first spring arm and electrically connecting the first conductive layer to the first electrical trace; and
a second connector mounting the second end of the one or more piezoelectric material actuator layers to the second spring arm and electrically connecting the second conductive layer to the second electrical trace.

16. The suspension structure of claim 13 wherein the stiffener layer is a plated metal layer.

17. The suspension structure of claim 16 wherein the stiffener layer has a thickness that is at least five times thicker than the thicknesses of the first and second conductive layers.

18. The suspension structure of claim 13 wherein the stiffener layer has a thickness that is at least five times thicker than the thicknesses of the first and second conductive layers.

19. The motor of claim 13 , wherein the first conductive layer and the second layer is a first metal and the stiffener layer is a second metal.

20. The suspension structure of claim 19 wherein:
the first metal includes copper; and
the second metal includes nickel.

Assignees

• Hutchinson Technology

Inventors

• Bjorstrom Jacob D

Classifications

• G11B5/4853

  Constructional details of the electrical connection between head and arm · CPC title

• G11B5/4826

  Mounting, aligning or attachment of the transducer head relative to the arm assembly, e.g. slider holding members, gimbals, adhesive (G11B5/484 takes precedence; details of head housings or structures G11B5/10, G11B5/127; adjustment relative to the record carrier G11B5/56) · CPC title

• G11B5/483 Primary

  Piezoelectric devices between head and arm, e.g. for fine adjustment · CPC title

• G11B5/4833

  Structure of the arm assembly, e.g. load beams, flexures, parts of the arm adapted for controlling vertical force on the head (G11B5/484 takes precedence) · CPC title

• G11B5/4873

  the arm comprising piezoelectric or other actuators for adjustment of the arm · CPC title