DSA suspension having PZT with overhanging constraint layer and electrical connection thereto
First Claim
1. A dual stage actuated suspension for a hard disk drive, the suspension comprising:
- a beam supporting a read/write head at a distal end thereof for writing data to, and reading data from, a data disk;
a microactuator assembly for effecting fine positional movements of the read/write head, the microactuator assembly comprising;
a piezoelectric element having a top face and a bottom face, the piezoelectric element'"'"'s bottom face being bonded by adhesive to the suspension, the two faces defining a driven electrode and a ground electrode; and
a layer of stiff material having a Young'"'"'s modulus of at least 50 GPA covering a majority of the top face, and also extending past an edge of the piezoelectric element and defining an overhang of said stiff material beyond the piezoelectric element.
1 Assignment
0 Petitions
Accused Products
Abstract
A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer may extend beyond the edge of the PZT to define an overhang, with the electrical connection being made by bonding to the underside of the overhang thus reducing and controlling the height of the assembly.
26 Citations
18 Claims
-
1. A dual stage actuated suspension for a hard disk drive, the suspension comprising:
-
a beam supporting a read/write head at a distal end thereof for writing data to, and reading data from, a data disk; a microactuator assembly for effecting fine positional movements of the read/write head, the microactuator assembly comprising; a piezoelectric element having a top face and a bottom face, the piezoelectric element'"'"'s bottom face being bonded by adhesive to the suspension, the two faces defining a driven electrode and a ground electrode; and a layer of stiff material having a Young'"'"'s modulus of at least 50 GPA covering a majority of the top face, and also extending past an edge of the piezoelectric element and defining an overhang of said stiff material beyond the piezoelectric element. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A dual stage actuated suspension for a hard disk drive, the suspension comprising:
-
a beam supporting a read/write head at a distal end thereof for writing data to, and reading data from, a data disk; a microactuator assembly for effecting fine positional movements of the read/write head, the microactuator assembly comprising; a piezoelectric element having a top face and a bottom face, the piezoelectric element'"'"'s bottom face being bonded by adhesive to the suspension, the two faces defining a driven electrode and a ground electrode; and a layer of stiff material covering a majority of the top face, and also extending past an edge of the piezoelectric element and defining an overhang of said stiff material beyond the piezoelectric element; and an electrical conductor comprising conductive adhesive attached to an underside of the overhang. - View Dependent Claims (10)
-
-
11. A dual stage actuated suspension for a hard disk drive, the suspension comprising:
-
a beam supporting a read/write head at a distal end thereof for writing data to, and reading data from, a data disk; and a microactuator for effecting fine positional movements of the read/write head, the microactuator comprising; a piezoelectric layer; a layer of metal on the bottom face of the piezoelectric layer defining a bottom electrode thereof, the bottom electrode being bonded by an adhesive to the suspension; a layer of metal on a majority of the top face of the piezoelectric layer defining a top electrode thereof, and extending beyond an edge of the microactuator to define a metal overhang, and further defining a restraining layer such that when the microactuator is activated, the restraining layer alters a bending behavior of the microactuator so as to increase an effective stroke length of the microactuator; a first conductive adhesive between the bottom electrode of the piezoelectric layer and a first electric potential source; and a second conductive adhesive between a bottom face of the metal overhang and a second electric potential source; wherein no conductive adhesive extends above the top electrode. - View Dependent Claims (12, 13, 14)
-
-
15. A dual stage actuated suspension for a hard disk drive, the suspension comprising:
-
a beam supporting a read/write head at a distal end thereof for writing data to, and reading data from, a data disk; a multilayer piezoelectric microactuator for effecting fine positional movements of the read/write head, comprising; a lower piezoelectric layer; a lower metal layer on an underside of the lower piezoelectric layer; an adhesive adhering the lower metal layer to the suspension; a middle metal layer on a top side of the lower piezoelectric layer; and an upper piezoelectric layer on the middle metal layer; the middle metal layer and the upper piezoelectric layer each extending beyond an edge of the lower piezoelectric layer. - View Dependent Claims (16, 17, 18)
-
Specification