Abstract: A plate member is made of a metal material lighter than stainless steel in a suspension for a head slider. This leads to a reduction in the weight of the suspension. The natural frequency of the suspension is thus raised. Moreover, the viscoelastic member is interposed between the front surface of the plate member and the back surface of the flexure. This structure allows either the plate member or the flexure to act as a base and the other to act as a constraining member. In other words, the plate member, the flexure and the viscoelastic member in combination act as a so-called vibration damper including constraining layers. The viscoelastic member serves to further suppress vibration of the plate member and the flexure.

Abstract: Disclosed herein is a head actuator for a head provided so as to accessible to a disk-shaped recording medium rotating above a base. The head actuator includes a main actuator driven so as to rotate above the base, and a microactuator driven so as to swing relative to the main actuator. The head is mounted on the microactuator. The main actuator and the microactuator are controlled so that the head is moved in a substantially radial direction of the recording medium and positioned over a desired track of the recording medium. A primary resonant frequency of mechanical characteristics of the main actuator is set to 100 Hz or higher. This setting may be achieved by increasing a preload in a ball bearing of the main actuator, for example, to thereby increase the rigidity of a nonlinear spring of the ball bearing. In the case that a disturbance acts on the main actuator, the above setting allows a reduction in displacement of the microactuator required for positioning of the head over the desired track.

Abstract: An acceleration sensor, for detecting the acceleration of a motion made by a head actuator that includes a carriage which is borne on a base of a disk drive so that it can pivot and a head suspension fixed to the distal part of the carriage, is formed using at least one shearing piezoelectric element having an electrode formed on both sides thereof. One of the electrodes is attached to the distal part of the carriage with a suspension base between them, while the other electrode is attached to the proximal part of the head suspension with a head mounting block between them. The shearing piezoelectric element is realized with one shearing piezoelectric element that is polarized in a direction orthogonal to the longitudinal directions of the carriage. Consequently, a large output is produced with only a small weight added to the carriage of the disk drive.

Abstract: A pair of slits are defined in a slider body of a head slider so as to extend from a trailing end surface to the leading end on the slider body. A movable block is established in the slider body between the slits. The slits ensure the extent of movement for the movable block. Elongated plates enable a relative displacement between the movable block and a stationary block. A head element is mounted on a trailing end surface of the movable block. The thickness of a non-magnetic layer corresponds to the gap length of the head element. The gap length of the head element can easily be controlled based on deposition of the non-magnetic layer. The thickness of the non-magnetic layer can be reduced in a relatively facilitated manner, so that the gap length of the head element can easily be minimized.

Abstract: The operation of the changing mechanism is set to enhance the intensity of the urging force if the acceleration sensor detects an impact. The head slider is urged against the surface of the recording medium with the urging force of a larger intensity. Accordingly, the head slider is allowed to keep contacting the recording medium irrespective of the impact. The head slider is thus prevented from jumping up from the surface of the recording medium. A collision is surely avoided between the head slider and the recording medium. In addition, the head slider is urged against the surface of the recording medium when the recording medium stands still. The head slider is completely prevented from dropping onto the recording medium.

Abstract: A fine positioning mechanism is provided in a disc drive for driving a head that records data onto and reproduces data from a disc. The mechanism includes a base fixed to an arm and a suspension, the base connecting the suspension to the arm, the arm swinging around a rotary shaft, and the suspension supporting the head. A drive part is located above the base, for deforming the base, the drive part including a shear type piezoelectric element that is polarized in a direction orthogonal to a thickness direction of the piezoelectric element, and deforms top and bottom surfaces of the piezoelectric element perpendicular to the thickness direction when voltage is applied to the piezoelectric element in the thickness direction.

Abstract: A piezoelectric element of a piezoelectric actuator is clamped by two electrodes, each of which has a conductive layer on a insulating layer. At least a connection terminal is formed by extending the conductive layer outside the insulating layer.

Abstract: An acceleration sensor, for detecting the acceleration of a motion made by a head actuator that includes a carriage which is borne on a base of a disk drive so that it can pivot and a head suspension fixed to the distal part of the carriage, is formed using at least one shearing piezoelectric element having an electrode formed on both sides thereof. One of the electrodes is attached to the distal part of the carriage with a suspension base between them, while the other electrode is attached to the proximal part of the head suspension with a head mounting block between them. The shearing piezoelectric element is realized with one shearing piezoelectric element that is polarized in a direction orthogonal to the longitudinal directions of the carriage. Consequently, a large output is produced with only a small weight added to the carriage of the disk drive.

Abstract: The small and light piezoelectric actuator of the present invention is capable of highly precisely positioning a magnetic head assemblies, etc. The piezoelectric actuator comprises: a movable member to which a head suspension is fixed; a fixed member fixed to a carriage arm; piezoelectric elements provided between the movable member and the fixed member and capable of adjusting a position of the head suspension by their deformation; and an electrode member electrically connected to one of electrodes of each of the piezoelectric elements. The movable member is adhered on the piezoelectric elements and electrically insulated from the other electrodes of the piezoelectric elements. The electric conductive layer of the electrode member and the other electrode of each of the piezoelectric elements are electrically connected to cables, which are provided to the head suspension so as to actuate the piezoelectric elements.

Abstract: A head suspension supporting a head at the tip end is allowed to swing at the tip end of a carriage in a recording disk drive. A microactuator is interposed between the head suspension and the carriage. A resistor is connected to the microactuator in serial. The microactuator is allowed to function as a capacitance. A combination of the microactuator and the resistor enables establishment of a so-called low pass filter. A high frequency noise involuntarily introduced in the driving voltage for the microactuator can be eliminated or removed from the driving voltage. Elimination of the high frequency noise enables a reliable prevention of the mechanical or physical resonance or vibration in the head suspension. A tracking action of the head related to a target recording track can reliably be stabilized.

Abstract: A head drive device for positioning a read and/or write head for reading and/or writing information to and from a disk coated with a recording medium, the head drive device including a carriage, a main actuator for moving the carriage, a plurality of heads for reading and/or writing information to and from the disk, and a vibration control portion comprising a plurality of micro-actuators positioned between the carriage and the heads, such that when the main actuator and a first micro-actuator are driven to enable precise positioning of a desired head with respect to a surface of the disk a second micro-actuator is driven so as to offset vibrations generated at the carriage by the operation of the desired micro-actuator.

Abstract: The operation of the changing mechanism is set to enhance the intensity of the urging force if the acceleration sensor detects an impact. The head slider is urged against the surface of the recording medium with the urging force of a larger intensity. Accordingly, the head slider is allowed to keep contacting the recording medium irrespective of the impact. The head slider is thus prevented from jumping up from the surface of the recording medium. A collision is surely avoided between the head slider and the recording medium. In addition, the head slider is urged against the surface of the recording medium when the recording medium stands still. The head slider is completely prevented from dropping onto the recording medium.

Abstract: A pair of slits are defined in a slider body of a head slider so as to extend from a trailing end surface to the leading end on the slider body. A movable block is established in the slider body between the slits. The slits ensure the extent of movement for the movable block. Elongated plates enable a relative displacement between the movable block and a stationary block. A head element is mounted on a trailing end surface of the movable block. The thickness of a non-magnetic layer corresponds to the gap length of the head element. The gap length of the head element can easily be controlled based on deposition of the non-magnetic layer. The thickness of the non-magnetic layer can be reduced in a relatively facilitated manner, so that the gap length of the head element can easily be minimized.

Abstract: A head carriage assembly drive system has a head carriage assembly having a head, a head carriage for moving the head in a radial direction of a rotating disk, a first drive unit for generating the power to rotate the head carriage and a second drive unit having a torque constant smaller than the torque constant of the first drive unit. Mainly the first drive unit is operated in a low-frequency band and mainly the second drive unit is operated in a high-frequency band, thereby reducing overall power consumption during tracking.

Abstract: A head carriage assembly drive system has a head carriage assembly having a head, a head carriage for moving the head in a radial direction of a rotating disk, a first drive unit for generating the power to rotate the head carriage and a second drive unit having a torque constant smaller than the torque constant of the first drive unit. Mainly the first drive unit is operated in a low-frequency band and mainly the second drive unit is operated in a high-frequency band, thereby reducing overall power consumption during tracking.

Abstract: A fine positioning mechanism is provided in a disc drive for driving a head that records data onto and reproduces data from a disc. The mechanism includes a base fixed to an arm and a suspension, the base connecting the suspension to the arm, the arm swinging around a rotary shaft, and the suspension supporting the head. A drive part is located above the base, for deforming the base, the drive part including a shear type piezoelectric element that is polarized in a direction orthogonal to a thickness direction of the piezoelectric element, and deforms top and bottom surfaces of the piezoelectric element perpendicular to the thickness direction when voltage is applied to the piezoelectric element in the thickness direction.

Abstract: An actuator includes a shear-type piezoelectric element of predetermined thickness and an opposed electrode formed on two electrodes in spaced relationship on a base member. The opposed electrode is displaced in accordance with the direction of polarization of the shear-type piezoelectric element upon applying a voltage between the two electrodes. The opposed electrode thus constitutes an operating section of the actuator. The actuator can be incorporated as a part of the head actuator to constitute a head-positioning mechanism capable of displacing the head by a minuscule distance independently of the operation of the head actuator.

Abstract: A mechanism for producing a minute movement of a head of a disk device, which simplifies wiring in a head actuator and reduces the cost of the device by decreasing the distance between adjacent carriage arms for putting a recording medium therebetween. The mechanism for producing a minute movement of the head is placed between the base portion of a head suspension and the leading end portion of each of the carriage arms of a rocking type head actuator. This mechanism consists of an actuator base fixed at the end portion of a carriage arm, a hinge plate attached to the base portion of a head suspension, and shearing type piezoelectric elements interposed between opposite surfaces of an actuator base and the hinge plate. A step portion is provided at an end portion of the actuator base. The piezoelectric elements are placed in a portion corresponding to the thickness of the carriage arm.

Abstract: A head carriage assembly is provided. A secondary magnetic driving device situated on a side of a hub portion is of a movable coil type, and includes a movable coil and a magnetic circuit body. The movable coil has an axial line perpendicular to a surface including a rotational center shaft, and is secured to a side surface of the hub portion. The magnetic circuit body 85 is made up of a U-shaped yoke and a permanent magnet. A yoke side surface penetrates through an opening of the movable coil, with a little room being left in the opening. A long side of the movable coil is engaged with the magnetic gap, also with a little room being left. The yoke side surface serves as the iron core of the movable coil. In a tracking operation, the secondary magnetic driving unit is actuated. A point in the movable coil where force is generated is distant from the rotational center shaft, and the torque constant of the point is large.

Abstract: Disclosed herein is a head actuator for a head provided so as to accessible to a disk-shaped recording medium rotating above a base. The head actuator includes a main actuator driven so as to rotate above the base, and a microactuator driven so as to swing relative to the main actuator. The head is mounted on the microactuator. The main actuator and the microactuator are controlled so that the head is moved in a substantially radial direction of the recording medium and positioned over a desired track of the recording medium. A primary resonant frequency of mechanical characteristics of the main actuator is set to 100 Hz or higher. This setting may be achieved by increasing a preload in a ball bearing of the main actuator, for example, to thereby increase the rigidity of a nonlinear spring of the ball bearing. In the case that a disturbance acts on the main actuator, the above setting allows a reduction in displacement of the microactuator required for positioning of the head over the desired track.