JPH01122083A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain a high-speed access by moving a transducer to a prescribed position by the detection signal of an optical encoder located in the neighborhood of a driving motor. CONSTITUTION:Since a transducer 6 and a driving coil 11 make an inverted trapezoidal letter shape like an alternate long and short dash line A, a space is large and a large motor for driving can be used. Since an optical encoder 14 of an actuator 9 is very close to a coil 11, when a servo system is constructed, the interval between a driving force and a rotational displacement detecting part to obtain an error signal becomes short, rigidity is improved and therefore, a stable positioning can be attained. By fixing the encoder 14 in the neighborhood of the coil 11, a positioning servo system can be constructed without being influenced by a frequency change. Thus, the high-speed access can be realized.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a storage device, and more particularly, to a storage device, and more particularly, to a storage device, and more particularly, to a storage device, and more particularly, to a storage device that is capable of transmitting data to a disk or other medium on which information is recorded. The present invention relates to a recording/reproducing device having an actuator capable of reciprocally positioning a sensor along a straight line or circumference.

(Prior Art) Recently, in winchiesta type disk drive devices,
There is an increasing demand for small-sized, large-capacity magnetic disk storage devices. As a result of recent developments, it has become possible to increase track density, and attempts have therefore been made to provide actuators that are compact and can be accessed at extremely high speeds.

A conventional technique used for this purpose is shown in FIG. Head slider 1 with transducer attached
11, a pivot portion 113 at the center of rotation of the arm assembly, a suspension 114 that attaches the head slider 111 to the arm assembly 112, and a voice coil motor 115 that drives the arm assembly. Well structured (OB6.817
/'71 A transducer is attached to the head slider. The transducer reads the position signal written on the recording disk and feeds it back to the voice coil motor Vc to form a positioning servo system to position the actuator. This allows for high-density recording and fast access speed, but it is difficult to increase the dynamic rigidity of the actuator's pivot portion, and the servo system tends to become unstable.

Another conventional example is shown in FIG. 8 (U, S, P, 784, 90
5').

This uses a stepping motor 116 to position the actuator with only mechanical precision. Although the configuration is simple and it can be made inexpensive, the positioning accuracy is not as high as that of a stepping motor, so it has the disadvantage that high density cannot be achieved. Also, the access speed cannot be increased.

An improved version uses a DC motor with an encoder instead of the stepping motor. Since the angular position is obtained using an encoder and fed back to the DC motor, it can be accessed faster than a stepping motor. However, since a conversion mechanism is required to transmit the rotation of the motor to the actuator, both speed and accuracy are worse than in the conventional example shown in FIG.

(Problems to be Solved by the Invention) As mentioned above, conventional recording and reproducing devices have problems such as the servo system tends to become unstable, or the positioning speed and positioning accuracy are insufficient. Ta.

The present invention is intended to solve the above-mentioned problems.
It is an object of the present invention to provide a recording/reproducing device which has a simple configuration, is suitable for a small device, is capable of high-speed access, has a stable servo system, has good positioning accuracy, and is suitable for high-density recording.

[Structure of the invention]

(Means for Solving the Problems) The recording and reproducing apparatus of the present invention includes a recording medium for recording information, at least one transducer for recording and reproducing information, and a device for installing the transducer. A recording/reproducing device comprising an arm for positioning the recording medium at a predetermined position, and a drive motor for rotating the arm around a predetermined rotation center, wherein the arm is provided near the drive motor and rotates the arm. The transducer is configured to include an optical encoder that detects the amount of displacement, and a subsequent control section that moves the transducer to a predetermined position based on a detection signal from the optical encoder.

(Function) With this configuration, the rotational displacement detection section of the actuator is located right next to the drive coil, so when the servo system is configured, the rotational displacement detection section receives the driving force and error signal. Since the gap is short and rigidity is increased, a stable positioning servo system can be constructed.

By providing the rotational displacement detection section on the outer periphery of the drive motor, the detection accuracy of the rotational displacement detector can be lowered.

By using an optical encoder in the rotation detection section, noise caused by the drive current, motor magnet, etc. is less likely to be added to the detection signal even in the vicinity of the coil. A slit section is provided on the moving coil frame, and the light emitting section, light receiving section, etc., which are heavy, have low rigidity, and are easily damaged, are provided on the fixed side, so the actuator can be made lightweight and highly rigid. Furthermore, there is no need to run a weak and easily broken displacement detector cable over the actuator.

The direction of movement can be detected by using two slits that are shifted by one and a half pitches.

Since the pivot part does not enter the servo path, it does not need to be rigid and can be made smaller.

Straight lines connecting the transducer, the center of driving force, and the center of rotation intersect within a range of 90 degrees from zero degrees.

Therefore, the drive coil can be made larger than in the case where the three points are arranged substantially in a straight line, and it is suitable for high-speed access.

(Embodiment) FIG. 1 is a schematic configuration diagram of a recording and reproducing apparatus showing an embodiment of the present invention. 1 is a rotating magnetic disk on which information is read and written. 2 is a spindle motor that rotates the magnetic disk. 3 is a frame to which the spindle motor is fixed, and 4 is a lid on the frame. The space between the lid 4 and the frame is sealed, and the air inside the device is constantly purified by the air filter 5.

6 is a transducer, which is a magnetic head equipped with an air bearing. Reference numeral 7 denotes a suspension that constitutes a transducer and supports the magnetic head.

8 is an arm that fixes the suspension eye to the actuator body. Reference numeral 9 denotes an actuator body that rotates around a pivot 10 that is the center of rotation, and supports the drive coil 11 and the arm 8.

The pivot 10 is composed of a rotating shaft 10a and a bearing 10b, and the bearing 10b has two legs, both of which are disposed within the frame 3, and the rotating shaft 10a is supported on a cantilever, forming an extremely thin pivot part. are doing.

Reference numeral 11 denotes a fan-shaped, flat drive coil, which obtains driving force from two sides radially extending from the pivot direction. York 15, 16. The permanent magnet 17 constitutes a magnetic circuit, and together with the drive coil 11 constitutes a drive motor. 1
2 is a coil frame to which the drive coil 11 is fixed. The coil frame 12 is made of glass and has a slit portion 13 printed on its outer periphery.

In this embodiment, pivot 10'f: center transducer'? 6 and the drive coil 11 are not arranged in a straight line as in the conventional case, but are in an inverted V-shape as shown by the dashed line A in FIG. 1(a). Therefore, in view of space limitations, a large drive motor that can provide a large drive force can be used, and high-speed access can be achieved.

Reference numeral 14 denotes a sensor section consisting of two slit sections shifted by a half pitch, a phototransistor forming a light receiving section, and an LED forming a light emitting section, and together with the slit section 13, constitutes a rotational position detecting section. By feeding back the servo signal obtained from the light receiving section to the drive coil 11, the drive coil 11 can be positioned at an arbitrary position, and as a result, the magnetic head 6 can be positioned at an arbitrary position.

The slit section 13 is made up of two facing plates in which a shielding section that blocks passing light and a hole section that allows it to pass are lined up in a ladder shape (slit shape). Displacement is detected by detecting the light beam passing through the plate. As the sight passing through the two plates changes in accordance with the amount of deviation as shown in Figure 3, the displacement can be detected.

In this embodiment, as shown in FIG. 4, a sufficiently long slit portion 13a is provided on the outer periphery of the drive motor, and two slit portions 13 with a pitch shifted by half a cycle are formed on a fixed portion such as a frame.
b is placed. The two fixed slits are of short length. In the optical encoder, a light emitting section 25 and a light receiving section 26 are arranged in a fixed part with two slit parts in between.

The drive motor is positioned at an arbitrary position by feeding back the displacement obtained from the rotational displacement detection section to the drive motor. When the drive motor is positioned, the transducer integrated with the motor is positioned at an arbitrary position, and information can be read and written.

Note that, as shown in FIG. 4, the rotational direction (movement direction) of the actuator can be detected by using two slit portions 13 that are shifted by a half pitch. 25 is a light emitting section such as an LED, and 26 is a light receiving section.

FIG. 2 is a sectional view of the drive motor in the moving direction. A rare earth magnet such as a samarium-cobalt magnet is optimal for the permanent magnet 17, and two magnets 17a and 17 magnetized in opposite directions are used.
It is composed of b.

The magnetic field of the magnetic gap is formed as shown by the arrow, resulting in a magnetic circuit with less leakage magnetic flux. 21a and 21b are pillars that connect the upper and lower yokes, and since a magnetic field does not pass therethrough, a non-magnetic material may be used. This drive motor is particularly suitable for thin devices.

In the drive motor, the drive coil is a fan-shaped short coil with a flat coil, and the magnetic circuit has a permanent magnet and two yokes with the drive coil in between.

The permanent magnet is divided into two parts and magnetized in opposite directions.

The magnetic field goes around the magnet, gap, yoke, gap, magnet, yoke, magnet. Since there is only one gap in the gap direction, it is suitable for thinning.

By using glass or the like printed with a moiré pattern as the coil frame of the flat coil, weight reduction and reliability improvement can be achieved.

The operation of the present invention will be explained. The recording/reproducing device of the present invention has a system in which the rotational displacement detection section of the actuator is located close to the drive coil, and the distance between the rotational displacement detection section that receives the driving force and the error signal when configuring the servo system is short. Due to increased rigidity, a stable positioning servo system can be constructed.

The reason for this will be explained with reference to FIG.

As in the present invention, an optical encoder (rotational displacement detecting section) is installed near the drive coil 11 that generates the driving force, and an optical encoder (rotational displacement detecting section) is installed near the transducer 6 that is actually positioned as in the conventional method. A comparison will be made with a device equipped with a rotational displacement detection section. FIG. 5 shows the state of the response of the transducer 6 (G==
) (t is current, α is acceleration) and phase (θ) are shown on the vertical axis.

FIG. 5(b) shows a system in which a rotational displacement detection section is provided near the transducer 6. In the figure, θ is the rotation direction of the transducer 6 in terms of phase, and is usually -
However, in the case of the one shown in Fig. 5(b), there is a deviation of 180" from the normal rotation direction after a certain frequency.
The positioning accuracy deteriorates because the rotation occurs in the direction of -360@ after the 0@ shift.

However, if an optical encoder is attached near the drive coil 11 as shown in FIG. 5(a), a stable positioning servo system can be constructed that is not affected by frequency changes.

Furthermore, by providing the rotational displacement detection section on the outer circumference of the drive motor, it is possible to use a rotational displacement detector with low detection accuracy.

As described above, in this embodiment, since the rotation detecting section uses an optical encoder, noise caused by the drive current, motor magnet, etc. is less likely to be added to the detection signal even in the vicinity of the coil. A slit section is provided on the moving coil frame, and the light emitting section, light receiving section, etc., which are heavy and tend to have weak rigidity, are provided on the fixed side, so the actuator can be made lightweight and highly rigid. By the way, there is no need to run the weak and easy-to-break displacement detector cable over the actuator.

By using two slits that are shifted by a half pitch, the direction of movement can be detected.

Since the pivot part does not enter the servo path, it does not need to be rigid and can be made smaller.

Furthermore, the center of the transducer 6, the r driving force and the center of rotation (pivot part 10) are not aligned in a straight line as in the conventional case, but are aligned in a V-shape with respect to the recording medium as shown in FIG. Therefore, compared to conventional devices, a larger motor can be used in the same space, and high-speed access can be achieved.

Another embodiment of the present invention is shown in Fig. 86 below.

Here, the same parts as in FIGS. 1 to 3, which only show the actuator part, are given the same reference numerals and detailed explanations will be omitted.

This embodiment differs from the previous embodiment in the configuration of the drive motor that generates the driving force and the configuration of the rotational position detection section (optical encoder).

The drive motor is composed of a rectangular coil 11' of a Giroto coil, a yoke 15'16', and permanent magnets 173' and 17b' (not shown). The configuration of the optical encoder is such that the slit portion 13' is fixed to the fixed side and the sensor portion 14 is fixed to the movable side, and such a configuration may be used.

In this embodiment as well, the optical encoder is provided near the drive coil 11', and the transducer 6, the center of the drive force, and the center of rotation (pivot portion 10) are aligned with respect to the recording medium IK as shown in FIG. They are arranged in a V-shape.

Note that the present invention is not limited to the above-mentioned embodiments, and can be modified in various ways. For example, the type of drive motor,
The arrangement of the transducer 6, the center of driving force and the center of rotation (pivot part), the type of optical encoder, etc. can be changed as appropriate.

Additionally, although the present invention has been described with respect to a Winkiester-type disk drive, the present invention may be used with other types of electromagnetic storage devices, or with one or more optical transducers. It is also possible to apply the user directly to an optical storage device incorporating the user into the actuator.

〔Effect of the invention〕

As described above in detail, the present invention provides a recording/reproducing device that is suitable for device miniaturization, enables high-speed access, has little magnetic noise, and can configure a stable servo system with a high mechanical resonance frequency. Obtainable.

[Brief explanation of the drawing]

FIG. 1 is a plan view and a cross-sectional view showing a schematic configuration of a recording/reproducing apparatus according to the present invention, FIG. 2 is a cross-sectional view of a drive motor according to the present invention, and FIG. 3 is a displacement diagram of an optical encoder according to the present invention. - Output diagram; FIG. 4 is a configuration diagram of the optical encoder according to the present invention; FIG. 5 is a comparison diagram of drive response states of the present invention and a conventional transducer; FIG. 6 is a modification of the present invention. FIGS. 7 and 8 are perspective views showing a conventional recording/reproducing apparatus. 1... Recording medium, 6... Transducer, 7...
・Suspension, 8... Arm, 9... Actuator body, 10... Pivot (rotation center), 11.
... Drive coil, 13... Slit part (optical encoder), 14... Senna part (optical encoder), 17... Permanent magnet. Agent: Patent Attorney: Nori Chika; Attorney: Mitsuyuki Matsuyama (b) Figure 1 Figure 2 Figure 4! (a) (b) Figure 6 Figure 8

Claims (6)

[Claims] (1) A recording medium for recording information, at least one transducer for recording and reproducing information, an arm for mounting the transducer and positioning it at a predetermined position on the recording medium, and rotating this arm about a predetermined rotation center. an optical encoder provided near the drive motor to detect the amount of rotational displacement of the arm; and an optical encoder for moving the transducer to a predetermined position based on a detection signal from the optical encoder. 1. A recording and reproducing device, comprising: a control unit for moving the device. (2) a rotation center of the transducer and the arm;
2. The recording/reproducing apparatus according to claim 1, wherein an imaginary line connecting the centers of the driving forces of the drive motor is formed in a V-shape with respect to the recording medium. (3) A patent characterized in that the optical encoder comprises an emitting section that generates light, a slit section that transmits and blocks the light, and a light receiving section that receives the light that has passed through the slit section. A recording/reproducing apparatus according to claim 1. (4) The slit portion includes a first slit portion in which slits are formed at a predetermined pitch, and a second slit portion in which slits are formed at least at the same pitch as the predetermined pitch; 4. The recording and reproducing apparatus according to claim 3, wherein the amount of rotational displacement of the arm is detected based on the amount of relative displacement of the two slits. (5) The slit portion includes a first slit portion in which slits are formed at a predetermined pitch, and slits having the same pitch and phase as the predetermined pitch, and a first slit portion in which slits are formed at a predetermined pitch. and a second slit section that is shifted in phase by half a pitch, and the rotational displacement amount and rotation direction of the arm are detected based on the relative displacement amount of the first and second slit sections. A recording/reproducing apparatus according to claim 3. (6) The recording/reproducing device according to claim 3, wherein the light emitting section and the light receiving section are attached to a fixed section that does not rotate with the rotation of the arm.