JPH0760630A - Surface grinding machine - Google Patents

Abstract

PURPOSE:To provide a surface grinding machine to carry out R curved surface forming machine work highly accurately on a medium sliding surface of a magnetic head. CONSTITUTION:A surface grinding machine has an R curved surface forming means of a medium sliding surface of a magnetic head 15, a measuring means to measure dispersion of gap depths for respective tracks in the magnetic head 15 at R curved surface grinding time, that is, a difference in both gap depths in both end tracks and an angle correcting table 10 to carry out angle correction on an inclined angle corresponding to a difference in the gap depths in R grinding work according to a value measured by the measuring means. The R curved surface forming means uses a grinding wheel 8 where a surface coming into contact with the magnetic head 15 being a grinding object is formed in an R curved surface shape, and a preset position of the R shape grinding wheel 8 is situated in the vertical direction to the medium sliding direction of the magnetic head 15. With constitution in this way, a grinding process can be easily automated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing device for performing R grinding on a magnetic head or the like.

[0002]

2. Description of the Related Art Generally, a so-called cylindrical grinder disclosed in JP-A-60-141465 is known in the manufacturing process of a magnetic head. As shown in the schematic diagram of FIG. 5, the machining of the R curved surface of the medium sliding surface of the magnetic head that comes into contact with the magnetic recording medium such as the magnetic tape is performed by the R curved surface by the grindstone rotating in the direction coaxial with the medium sliding direction of the magnetic head. The grinding process for forming the is performed.

By the way, in order to control the grinding amount in the grinder, an automatic sizing device is added in order to remove unstable factors such as dimensional fluctuation due to wear of the grinding wheel and thermal expansion of the work piece due to heat generated during grinding. Some of them and those of CNC (Computer Numerical Control) are seen, and as a dimension control method for grinding or lapping the gap depth of the magnetic head to a predetermined dimension, a visual recognition method using an optical microscope or There is known a method of detecting a change in resistance value of a resistor formed in a gap portion of a magnetic head.

[0004]

In the conventional grinding process using a cylindrical grinding machine, (1) the absolute processing amount is large, (2) chipping, cracks, or a work-affected layer on the work surface due to the grinding process is likely to occur. (3) Heat is easily generated by grinding on the machined surface. (4) Cylindrical grinder is a work loader
Since it is difficult to automate in terms of an unloader and the like, it was necessary to strictly control the grinding processing conditions for the workpiece (magnetic head).

In controlling the grinding amount in the grinder,
In order to improve the surface roughness of the ground surface of the work piece, when an elastic grindstone using a resinoid binder is used as the grinding grindstone, the cutting value of the grindstone and the grinding of the work piece due to the characteristics of the grindstone. The amount does not always match, and it has been difficult to control the amount of grinding with high accuracy even if the above-mentioned automatic sizing device or CNC device is added.

[0006] Above all, the grinder needs to grind the gap depth of the magnetic head to a predetermined size, and therefore must be managed with high accuracy. In addition, since the number of tracks is large and high recording density recording / reproducing is required as compared with a magnetic head applied to a digital type magnetic recording / reproducing apparatus whose technological development is remarkable these days, the gap depth of each track can be accurately adjusted. However, high-precision technology for uniform and uniform formation was required.

The present invention relates to a surface grinder that grinds an R curved surface of a magnetic head with high accuracy.

[0008]

A surface grinding machine for machining a curved surface of a medium sliding surface of a magnetic head, which comprises a curved surface forming means of a medium sliding surface of a magnetic head and a curved surface forming means for grinding the curved surface of the medium. Measuring means for measuring the variation of the gap depth for each track in the magnetic head, that is, the difference between the gap depths at both end tracks, and the gap depth during the R grinding process based on the value measured by the measuring means. Angle correction table for correcting the angle of inclination corresponding to the difference between the R shape and the R curved surface forming means using a whetstone having a curved surface in contact with the magnetic head to be ground. The setting position of the grindstone is characterized in that it is located in a direction perpendicular to the medium sliding direction of the magnetic head.

Further, the measuring means is characterized by measuring with a resistor formed in the gap portion of the magnetic head.

[0010]

By adopting the above construction, the contact surface of the grindstone with the work piece is formed into the R curved surface shape, so that automation can be easily performed in the loader / unloader of the work as compared with the cylindrical grinder. Become. In addition, since the processing uniformity of the magnetic head is controlled on the basis of the resistance value of the resistor provided in the workpiece, that is, the magnetic head, the dimensional accuracy due to the abrasion of the grinding wheel and the heat of the workpiece due to the heat generated during the grinding are controlled. It is possible to perform extremely high-precision surface grinding of a magnetic head without being affected by thermal expansion of a workpiece due to expansion.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

FIG. 5 shows the structure of the magnetic head 15. Figure 5
As shown in FIG. 3, the magnetic head 15 comprises a resistor 16, a resistor conductor wire 17, a track 18, a protective plate 19, and a substrate 20.
The resistor 16 is arranged inside for measuring the amount of grinding, the resistor 16 is scraped by grinding, and the amount of grinding can be grasped by measuring the resistance value. The resistor 16 is connected to a surface grinder by a resistor conductor wire 17 and has a structure that can be processed while correcting the grinding amount and inclination of the magnetic head 15.

FIG. 1 is a schematic view for explaining the operation of the surface grinder of the present invention. A whetstone 8 having a curved surface in contact with the magnetic head 15 to be ground is used, and the set position of the R-shaped whetstone 8 is positioned perpendicular to the medium sliding direction of the magnetic head 15 and rotates. The medium sliding surface (R curved surface forming surface) of the magnetic head 15 is brought into contact with the ground surface of 8 for polishing.

FIG. 2 shows a side view (a) and a front view (b) of the surface grinder in the embodiment of the present invention.

In FIG. 2A, reference numeral 1 is a bed, and the column 4 and the grindstone 8 are moved forward and backward by the motor 4. The spindle 6 and the grindstone 8 are moved up and down by the motor 7 to process the magnetic head 15. The grindstone 8 is rotated by the motor 9. Since the grindstone 8 processes the magnetic head 15 into an R shape,
Pre-shaped into an R shape. The table 2 is moved left and right by the motor 5 to process the magnetic head 15.

In FIG. 2B, the θ correction table 10 is driven by the motor 11 to raise or lower the θ correction table pushing mechanism 12 around the fulcrum 14 to perform θ correction of the magnetic head 15. The tension spring 13 stabilizes the operation.

Next, the operation of the surface grinder of the present invention will be described with reference to the flow chart shown in FIG.

Operation 1: The motor 4 operates to move the grindstone 8 in the front-back direction of the magnetic head 15, and the motor 7 operates to move the grindstone 8 in the up-down direction of the magnetic head 15.
Is activated to move the grindstone 8 in the left-right direction of the magnetic head 15 to bring the grindstone 8 into contact with the magnetic head 15.

Operation 2: The motor 7 operates and the grindstone 8 descends by a certain amount, and the grindstone 8 cuts into the magnetic head 15 by a certain amount.

Operation 3: The motor 5 operates to move the magnetic head 15 left and right, and the grindstone 8 processes the magnetic head 15 horizontally.

Operation 4: Resistor 16 in magnetic head 15
Is measured inside the control panel through the resistance conductor 17 to determine whether the values of the left and right resistors 16 are equal (whether the magnetic head 15 can be accurately processed).

Operation 5: If in operation 4, the magnetic head 15
If there is a difference in the values of the left and right resistors 16 inside, the motor 11 operates to operate the θ correction table 10 and the magnetic head 1
The angle θ is corrected so that 5 is processed evenly on the left and right.

Operation 6: The resistance value of the resistor 16 of the magnetic head 15 is measured inside the control panel through the resistor conductor wire 17, and the values of the left and right resistors 16 have reached the prescribed values (the magnetic head 15 regulates). Judgment was made).

If the value is not the specified value, the process returns to operation 2.

The operation is completed as described above.

[0026]

As described above, according to the present invention, by making the contact surface of the grindstone with the work piece into the R curved surface, automation can be easily performed in the loader / unloader of the work as compared with the cylindrical grinder. Like In addition, since the processing uniformity of the magnetic head is controlled on the basis of the resistance value of the resistor provided in the workpiece, that is, the magnetic head, the dimensional accuracy due to the abrasion of the grinding wheel and the heat of the workpiece due to the heat generated during the grinding are controlled. It is possible to perform extremely high-precision surface grinding of a magnetic head without being affected by thermal expansion of a workpiece due to expansion.

[Brief description of drawings]

FIG. 1 shows a schematic view of the operation of a surface grinder of the present invention.

FIG. 2 is a side view (a) of the configuration diagram of the surface grinder of the present invention,
The front view (b) is shown.

FIG. 3 shows an operation flow chart of the surface grinder of the present invention.

FIG. 4 shows a configuration diagram of a magnetic head.

FIG. 5 shows a schematic view of the operation of a conventional cylindrical grinding machine.

[Explanation of symbols]

 1 bed 2 table 3 column 6 spindle 8 R-shaped grindstone 12 θ compensation table pushing mechanism 13 tension spring 14 θ compensation table fulcrum 15 magnetic head 16 resistor 17 resistor conductor wire

Claims (2)

[Claims] 1. A surface grinder for forming a curved surface of a medium sliding surface of a magnetic head, comprising: a curved surface forming means for forming a medium sliding surface of the magnetic head; A variation in the gap depth between tracks, that is, a measuring means for measuring the difference between the two gap depths at both ends of the track, and a gap depth difference during R grinding based on the value measured by the measuring means. And an angle correction table for performing an angle correction of the tilt angle. The R curved surface forming means uses a grindstone having a curved surface in contact with the magnetic head to be ground, and the set position of the R shaped grindstone. Is a surface grinder characterized by being positioned in the direction perpendicular to the medium sliding direction of the magnetic head. 2. The surface grinder according to claim 1, wherein the measuring means measures with a resistor formed in a gap portion of the magnetic head.