Disk drive actuator having a C-shaped bobbin with wings adjacent longitudinal coil legs
View Patent ↗A C-shaped bobbin includes a bobbin base member adjacent and attached to a first lateral leg of an actuator coil. A bobbin recess, adjacent the bobbin base member, separates first and second bobbin wings. The first and second bobbin wings define first and second wing lengths measured parallel to first and second longitudinal legs of the coil, respectively, and also define first and second wing widths measured normal to the first and second longitudinal legs, respectively. The bobbin recess defines a recess depth measured normal to the first lateral leg, and defines a recess width measured parallel to the first lateral leg. Each of the first and second wing lengths is less than the length of the longitudinal legs. The recess depth is at least half a base member width. The recess width is at least twice the first wing width and/or the second wing width.
1. An actuator for a disk drive, the actuator comprising:
an actuator body having an actuator pivot bore and an actuator arm extending away from the actuator pivot bore along an arm longitudinal axis;
a conductive coil attached to the actuator body, the conductive coil including first and second lateral legs joined by first and second longitudinal legs to form a closed coil periphery, the first longitudinal leg defining a longitudinal leg length measured generally parallel to the arm longitudinal axis, the first and second lateral legs each being disposed in an orientation that is generally transverse to the arm longitudinal axis, the first lateral leg being disposed closer to the actuator pivot bore than the second lateral leg; and
a C-shaped bobbin disposed within the closed coil periphery and attached to the conductive coil, the C-shaped bobbin including
a bobbin base member adjacent and attached to the first lateral leg, the bobbin base member defining a base member width measured normal to the first lateral leg;
a first bobbin wing adjacent and attached to the first longitudinal leg, the first bobbin wing defining a first wing length measured parallel to the first longitudinal leg and defining a first wing width measured normal to the first longitudinal leg;
a second bobbin wing adjacent and attached to the second longitudinal leg, the second bobbin wing defining a second wing length measured parallel to the second longitudinal leg and defining a second wing width measured normal to the second longitudinal leg; and
a bobbin recess between and separating the first and second bobbin wings and adjacent the bobbin base member, the bobbin recess defining a bobbin recess depth measured normal to the first lateral leg and a bobbin recess width measured parallel to the first lateral leg;
wherein each of the first and second wing lengths is less than the longitudinal leg length so that the first and second bobbin wings do not contact the second lateral leg, the bobbin recess depth is at least half the base member width, the bobbin recess width is at least twice the first wing width, and the bobbin recess width is at least twice the second wing width.
2. The actuator of claim 1 wherein the first and second wing lengths are equal.
3. The actuator of claim 1 wherein the first and second wing widths are equal.
4. The actuator of claim 1 wherein the first wing length is in the range of ⅓rd to ⅘th the longitudinal leg length.
5. The actuator of claim 1 wherein the first wing width is in the range of ⅛th to ½ the bobbin recess width.
6. The actuator of claim 1 wherein the base member width is in the range of ⅛th to ⅓rd the longitudinal leg length.
7. The actuator of claim 1 wherein the bobbin recess depth is in the range ¼th to ⅔rd the longitudinal leg length.
8. The actuator of claim 1 wherein the C-shaped bobbin comprises a metal material.
9. The actuator of claim 1 wherein the first lateral leg defines a first lateral leg length measured generally transverse to the arm longitudinal axis, and wherein the bobbin recess width is in the range of ⅗th to 6/5th the first lateral leg length.
10. A disk drive comprising:
a disk drive base;
a spindle rotably coupled to the disk drive base, and a disk attached to the spindle; and
an actuator, the actuator including:
an actuator body having an actuator pivot bore and an actuator arm extending away from the actuator pivot bore along an arm longitudinal axis;
a conductive coil attached to the actuator body, the conductive coil including first and second lateral legs joined by first and second longitudinal legs to form a closed coil periphery, the first longitudinal leg defining a longitudinal leg length measured generally parallel to the arm longitudinal axis, the first and second lateral legs each being disposed in an orientation that is generally transverse to the arm longitudinal axis, the first lateral leg being disposed closer to the actuator pivot bore than the second lateral leg; and
a C-shaped bobbin disposed within the closed coil periphery and attached to the conductive coil, the C-shaped bobbin including
a bobbin base member adjacent and attached to the first lateral leg, the bobbin base member defining a base member width measured normal to the first lateral leg;
a first bobbin wing adjacent and attached to the first longitudinal leg, the first bobbin wing defining a first wing length measured parallel to the first longitudinal leg and defining a first wing width measured normal to the first longitudinal leg;
a second bobbin wing adjacent and attached to the second longitudinal leg, the second bobbin wing defining a second wing length measured parallel to the second longitudinal leg and defining a second wing width measured normal to the second longitudinal leg; and
a bobbin recess between and separating the first and second bobbin wings and adjacent the bobbin base member, the bobbin recess defining a bobbin recess depth measured normal to the first lateral leg and a bobbin recess width measured parallel to the first lateral leg;
wherein each of the first and second wing lengths is less than the longitudinal leg length so that the first and second bobbin wings do not contact the second lateral leg, the bobbin recess depth is at least half the base member width, the bobbin recess width is at least twice the first wing width, and the bobbin recess width is at least twice the second wing width.