JPS60136076A - Disk device - Google Patents

Abstract

PURPOSE:To obtain a disk device excellent in reliability on position accuracy with a simple and inexpensive manufacturing process by forming a stopper which controls the shift range of a carriage in a body with a chassis of the disk device. CONSTITUTION:A rod-shaped projection part 1a is formed in a body with a chassis 1 on the side face of the chassis 1 set counter to a head carriage 3. The part 1a has a contact with a contact part 3b on the right side face of the carriage 3 to form a stopper which controls the shift range of the carriage toward the right side (outer circumferential direction of a magnetic disk 8) in the figure. In other words, the part 1a serves as a stopper of a conventional structure. In such a constitution, the variance range of a size G can be set within an allowable range R in terms of the accuracy of normal mechanical processing. Thus it is possible to detect an accurate TROO position and also to cope with an overshoot phenomenon.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a disk device, and more particularly to a disk device that records and reproduces information on a disk-shaped recording medium using a head element that is transferred to a carriage.

[Prior art]

A magnetic disk device that records and reproduces information on a disk-shaped magnetic recording medium is known as a typical disk device of this type.

The vicinity of a carriage drive mechanism of a conventional magnetic disk device is constructed as shown in FIG.

In FIG. 1, the reference numeral 8 indicates a magnetic disk which is a magnetic recording medium, and a center hole 8a formed in the center thereof is clamped by a clamping mechanism (not shown) of the magnetic disk device, and is connected to a drive mechanism (not shown) as well. Driven to rotate.

In the figure, the reference numeral 1 indicates the chassis of the magnetic disk device, and a head carriage 3 is slidably provided on two mutually parallel guide bars 2 fixed to the side surface of the chassis 1. ing.

The head carriage 3 is equipped with a magnetic helad 4 that slides into contact with the magnetic disk 8 to record and reproduce information on the back side in the figure of the tip of an arm portion 3a provided on the side facing the chassis.

In addition, a steel belt 6 wound around a pulley 5 which is rotationally driven by a stepping motor (not shown) is stretched on the lower side surface of the Herad carriage 3 in the figure, and the pulley 5 is rotationally driven by the stepping motor. As a result, the helad carriage 3 is driven and moved in the left-right direction in the figure via the steel belt 6 along the guide bar 2.2.

In addition, the reference numeral 7 in the figure is a stopper that restricts the movement range of the head gear lift 230 in the right direction in the figure. Alternatively, as shown by reference numeral 7' in FIG. 2, it may be provided as a stopper that comes into contact with the stepped portion of the pulley 5 to regulate the movement range of the head carriage 3.

Is this stopper in the conventional structure? (7') It is fixed to the pace of the magnetic disk device with screws or the like. A method of configuring this stopper as a G-shaped retaining ring fixed to the guide bar 2 is also adopted.

In the above configuration, when the power of the magnetic disk device is turned on during recording and reproduction, the head carriage 3 is first aligned so that the position of the magnetic head 4 matches the reference position on the magnetic disk 8, and then the head carriage 3 is driven leftward in the figure, the magnetic head 4 is aligned with a selected track position from among a number of concentric tracks formed on the magnetic disk 8, and recording and reproduction are performed.

By the way, in the above configuration, the mounting of the stopper 7 (7') is related to the positional accuracy of the reference position detection when aligning the magnetic head 4 to the reference position when the power is turned on, etc., and the overshoot of the helad carriage 30. Therefore, extremely high standards are required.

The details will be explained below.

Generally, the outermost track on the magnetic disk 8, that is, the position of TR0O is used as the reference position, and the position of the magnetic head 4, that is, the position of the head carriage 3, is generally used.
The TRoO position detection when adjusting the position of the magnetic head to this TR0O is performed by calculating the logical product of the output signal of a TR0O switch (not shown), which emits a signal when the position of the magnetic head reaches the vicinity of TR0O, and a specific phase signal of the stepping motor. Detected from the signal. This means that the track pitch is, for example, 96TP.
1 pitch is approximately 0 in I (Track Per Inch)
．． This is because it is extremely small at 265 m, and it is difficult to accurately detect the position of TR0O using only the output signal of the TR00 switch.

Specifically, for example, the stepping motor is 4-phase,
It is assumed that it is driven by repeated excitation in the order of 0 phase #1 phase #2 phase #3 phase #0 phase...The excitation of each phase corresponds to one track, and the O phase excitation corresponds to TR0O. If it is assumed that the above-mentioned 'rROo switch output signal and the O-phase excitation signal are ANDed, the position of TR0O is detected.

However, since the position of the head carriage 3 4 tracks in the outer circumferential direction from TR0O also corresponds to O-phase excitation, before the power is turned on, the head carriage 3 is at a position of 2 or more tracks in the outer circumferential direction from TR0O, for example, a position of 3 tracks. In this case, when the stepping motor is excited to the O phase by the power-on reset circuit in the magnetic disk device when the power is turned on, the bed carriage 3 moves from TR0O to a position corresponding to four tracks in the outer circumferential direction. Here, TR0
If the O switch outputs a detection signal of TR0O, this position will be erroneously detected as TR0O.

Therefore, the position of the stopper 7 is that the helad carriage 3 is TR0.
It is necessary to set it so that it does not move beyond the position of two tracks in the outer circumferential direction.

On the other hand, in the initial positioning of the head carriage described above, the head carriage 3 is moved from the inner circumferential side to the T
When it moves to R0O, as shown by the symbol S in FIG. 3, it stops at the TR0O position after an open neat motion of about 0.15 degrees in the outer circumferential direction from the TR0O position.

Therefore, in order to prevent the head carriage 3 and the stopper 7 from coming into contact with each other during this overshoot, taking this overshoot into consideration, the dimensions of the regulation range of the stopper 1 with respect to the head carriage 3 are determined by TR as shown in FIG.
The position indicated by the symbol TR-2 for two tracks in the outer circumferential direction from 0O, and 0.1 for the overshoot from TR0O.
5 mm from the outer circumference side position, that is, approximately 0.38 mm, which is obtained by subtracting 0.15 tm for overshoot from 0265 mm x 2 for 2 tracks. In other words, the allowable range R of the variation in the gap size between the contact portion 3b of the head carriage 3 and the contact surface of the stone puff 0 at the position of TR0O is approximately 038, and the stopper 7 must be provided with a smaller positional accuracy than this. .

However, as mentioned earlier, the stopper 7 has a structure that is fixed to the pace, the quick stopper, etc. with screws, etc., so this mounting sometimes requires position adjustment with the above-mentioned accuracy, and this process is difficult. Therefore, the reliability of accuracy is low, so it must be dealt with in the subsequent inspection process.

Also, depending on the software of the magnetic disk drive, there is a method to obtain the TR0O position by directly bringing the head carriage into contact with the stopper without using the above-mentioned TR0O detection signal detection.In this case, the stopper 7 has a structure in which it is fixed with a screw or the like. If so, the stopper may be displaced due to the impact of contact. Misalignment of the stopper causes false detection of TR0O.

The above drawbacks are not limited to magnetic disk drives, but are common to all disk drives having a carriage for transporting a head element.

〔the purpose〕

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a disk device that can be manufactured at low cost through simple steps and has excellent reliability in positional accuracy.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Details of embodiments of the present invention will be described below with reference to the drawings. Here, an example of application of the present invention to the above-mentioned magnetic disk device will be described as an example. In the figure, the same parts as in FIGS. 1 and 2 are denoted by the same reference numerals, and the explanation thereof will be omitted.

FIG. 5 shows the configuration of the main part of the embodiment of the present invention. As shown in the figure, in this embodiment, a rod-shaped protrusion is provided on the side surface of the chassis 1 facing the helad carriage 3. A convex portion 1a is formed by integral molding with the chassis 1, and this convex portion 1a abuts against a contact portion 3b on the right side of the head carriage 3 to move the head carriage 30 toward the right in the figure (the outer periphery of the magnetic disk 8). It is configured as a stopper that regulates the range of movement in the direction). That is, a protrusion 1a is provided in place of the stopper in the conventional structure.

The other parts are the same as the conventional structure.

In addition, what is indicated by the reference numeral 3C in the figure is a reference point provided on the helad carriage 3. Moreover, what is indicated by the reference numeral 4a is a magnetic gap of the magnetic helad 4.

According to the specific embodiment of the above configuration, the tolerances of each dimension are as follows.

The dimension indicated by the symbol a in the figure, that is, the magnetic disk 8
The tolerance of the dimension from the center of clamping to the magnetic gap 4a of the magnetic helad 4 located at the TR0O position is ±0.01
1 mm (hereinafter, the unit of dimension is omitted)1. Also, the tolerance of the dimension from the magnetic gap 4 to the reference point 3C on the head carriage 3 is 0004, and the tolerance from the reference point 3a to the head carriage 30 is 1 mm. Dimension C to the contact surface of contact part 3b
The tolerance of is ±0.08.

Therefore, the root mean square of the tolerance of the dimension A from the center of clamping the magnetic disk 8 to the abutment part 3b of the head carriage 3 is ± (0,011)21-(0,04)2+(0,08
)2=±0090.

Further, the tolerance of the dimension B from the clamp center of the magnetic disk 8 to the contact surface of the convex portion 1a of the chassis 1 is ±0.05.

Therefore, the dimension G of the gap between the abutting surface of the abutting part 3b of the head carriage 3 and the convex part 1a at the position TR0O is within the range of ±0.103, that is, 0.206. It varies within the width range.

The size of this range of 0.206 is smaller than the allowable range R of variations in the gap opening method shown in FIG. 4, which is about 0.138.

Also, in the above calculation, the root mean square was used, but even if the tolerances are added together, the tolerance of dimension A is ±(0,011+0.04+0.08)=±0131, and the tolerance of dimension G is +( 0,131+0.05) = ±0181, that is, the width varies within a range of 0.362, and this range 03
The size of 62 is smaller than the tolerance range R of about 0.38.

That is, according to the configuration of this embodiment, the range of variations in the dimension G due to the accuracy of normal machining is within the tolerance range R, and the above-mentioned TRoO position can be detected accurately, and overshoot can also be dealt with.

Further, according to the structure of this embodiment, since the convex portion 1a is formed by integral molding with the shear 1, there is no need to adjust its mounting position, and even if it comes into contact with the helad carriage 3, the impact No misalignment occurs. Furthermore, the number of parts required for the conventional stopper and its attachment is reduced. In addition, since the reliability of dimensional accuracy is improved, the inspection process is simplified.

In addition, in the above structure, by providing an elastic member on the self-contact surface of the convex portion 1a, it is also possible to absorb the contact noise generated when the head carriage 3 and the convex portion 1a abut. Further, the shape of the convex portion 1a is not limited to that of the embodiment, and the chassis itself may be used as a stopper. Further, the convex portion may be configured as a stopper that comes into contact with another portion such as a stepped portion of the pulley.

Furthermore, the configuration of the above embodiment is applicable not only to magnetic disk devices but also to disk devices using other disk-shaped recording media as long as they have a stopper that restricts the movement range of the carriage that transports the head element. Of course.

〔effect〕

As is clear from the above description, according to the disk device of the present invention, the stopper for regulating the movement range of the carriage for transporting the head element is formed integrally with the chassis.
High positional accuracy can be obtained without requiring a special position adjustment process for the stopper, and the reliability in positioning the head element is improved without positional deviation. In addition, the inspection process is simplified and the number of parts is reduced, so costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing the main structure of a conventional magnetic disk device, and FIG. 2 is a schematic plan view showing the structure of another conventional example.
FIG. 3 is a diagram illustrating the overshoot of the head carriage, FIG. 4 is an explanatory diagram showing the allowable range of the gap opening method between the head carriage and the stopper, and FIG. 5 is a diagram illustrating the magnetic disk according to the embodiment of the present invention. FIG. 2 is a schematic plan view illustrating the main structure of the device and the tolerances of each dimension. 1... Chassis 1a... Convex portion 3... Head carriage 3b... Contact portion 4...
Magnetic Herad 8...Magnetic disk patent applicant Canon Electronics Co., Ltd.

Claims (1)

[Claims] What is claimed is: 1. A disk device for recording and reproducing information on a recording medium disk by a head element transferred to a carriage, characterized in that a stopper for regulating the movement range of the carriage is integrally formed on the chassis of the disk device.