Disk device having flexure with protrusion

A disk device comprising:

• a magnetic disk;
• a magnetic head configured to read and write information from and to the magnetic disk;
• a flexure on which the magnetic head is mounted, the flexure including
• a first outer surface,
• a first pad on the first outer surface, and
• a second pad on the first outer surface apart from the first pad in a first direction along the first outer surface;
• a piezoelectric element including
• a second outer surface facing the first outer surface,
• a first electrode on the second outer surface, and
• a second electrode on the second outer surface apart from the first electrode in the first direction;
• a conductive, first bonding material that bonds the first pad and the first electrode;
• a conductive, second bonding material that bonds the second pad and the second electrode;
• and
• a protrusion provided on the flexure, located at least partially between the first bonding material and the second bonding material, and protruding from the first outer surface, wherein
• the flexure includes
• a metal plate,
• a first insulating layer,
• a second insulating layer located between the metal plate and the first insulating layer, and
• a conductive layer located between the first insulating layer and the second insulating layer,
• the conductive layer includes the first pad and the second pad,
• the first insulating layer with a first hole and a second hole has
• a first surface to which the first hole is open to expose the first pad, the first surface being included in the first outer surface, and
• a second surface to which the second hole is open to expose the second pad, the second surface being included in the first outer surface,
• the protrusion has an end surface that faces the second outer surface and is closer to the second outer surface than the first surface and the second surface,
• the metal plate includes
• a third surface facing the first pad and the second pad through the second insulating layer, and
• an inner protrusion located at least partially between the first bonding material and the second bonding material in the first direction and protruding from the third surface toward the piezoelectric element, and
• the protrusion includes a part of the first insulating layer, the part overlapping the inner protrusion in a direction orthogonal to the first outer surface.