JPH0373268A - Grinding method and grinding grindstone - Google Patents

Abstract

PURPOSE:To perform grinding while using the dressing of a tool by an electrolytic action as well without installing an electrode for dressing, by making a grinding grindstone itself a positive and negative electrode. CONSTITUTION:A work 10 is first interposed between a conductive grindstone 1 and conductive grindstone 3, which are worked and rotated, while feeding a water soluble grinding liquid 5 between work faces 1a and 3a from a grinding liquid feeding nozzle 6. Simultaneously with this, feeding is executed on the conductive grindstone 1 and conductive grindstone 3 via feeder brushes 7 and 8 from a power source device 9 to perform grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for grinding hard and brittle materials such as glass and ceramics, and more particularly to a method for grinding a tool in combination with dressing of a tool by electrolytic action.

[Conventional technology]

Conventionally, a processing method using a flat grinder shown in FIG. 6 has been proposed as a grinding process that is performed in combination with dressing of a tool by electrolytic action. An example of the ingenuity of such grinding processing is the 1989 Society for Precision Engineering Spring Conference Proceedings (page 373).

In FIG. 6, 101 is a conductive grindstone, and this conductive grindstone 101 is rotatably held.

The rotary table 102 is arranged opposite to the conductive grindstone 101 and is rotatable. Conductive grindstone 101
An electrode 103 is installed between the rotary table 102 and the grinding surface 101 a of the conductive grindstone 101 so as to closely face it, and the electrode 103 is connected to the negative electrode of a power supply device 104 .

A power supply brush 105 is in contact with the conductive grindstone 101 so that the positive electrode from the power supply device 104 can be fed to the conductive grindstone Iol.

In addition, the electrode 103 and the processed surface 101a of the conductive grindstone 101
A nozzle 107 for supplying water-soluble grinding fluid 106 is provided.

During processing, the workpiece 108 is placed between the conductive grindstone 101 and the rotary table 102, and the power supply 104 is supplied to the conductive grindstone 101 and the electrode 103 while constantly supplying water-soluble grinding fluid 106 from the grinding fluid supply nozzle 107.
The grinding process is carried out in the same manner as the known grinding process using a surface grinder.

According to the above conventional example, an electrolytic action occurs between the conductive grinding wheel 101 and the electrode 103 which are placed opposite each other via the water-soluble grinding fluid 106, and the binder is dimensionally larger than the machined surface Iota of the conductive grinding wheel 101. Since it is eluted little by little to the extent that it does not appear as a change and acts as a dressing, processing can always be performed without clogging.

[Problem to be solved by the invention]

However, in the conventional example, the electrode 103 is
The conductive grindstone 101 must be installed at a position close to and facing the processing surface 101a so as to always maintain a constant distance therebetween, and must be configured so as to exert its effect on the entire surface of the processing surface 101a. This can be achieved relatively easily with a cup-shaped grindstone whose processing surface area is small, but with a flat grindstone that is not cup-shaped, it is difficult to uniformly install the electrodes 103 all the way to the center.

In recent years, extremely thin workpieces with a wall thickness of 1 mm or less, such as ceramic blades, filters, and wafers, are often processed simultaneously on both sides in order to improve productivity and prevent distortion. In this case, the electrode 103 is connected to the conductive grindstone 101
If the electrode 13 is to be installed in a position close to and facing the machining surface 101a of the workpiece, an electrode that is even thinner than the workpiece must be installed in a cantilevered state. Unable to maintain constant spacing.

In addition, when the conductive grindstone 101 or the workpiece swings,
When the electrode is fixedly installed, there is a portion of the processed surface Iota of the conductive grindstone 101 that is not dressed.

Therefore, in order to exert its effect on the entire surface to be processed 101a, it is necessary to move the electrode in synchronization with these swings, which makes the moving means and control method complicated and difficult.

The present invention was developed in view of the above-mentioned problems, and is applicable in cases where it is difficult to properly install electrodes in conventional methods (simultaneous processing on both sides, etc.).
The object of the present invention is also to provide a method in which grinding can be performed while also using dressing of the tool by electrolytic action.

[Means and effects for solving the problem] The present invention has a configuration in which a pair of conductive grindstones are installed facing each other, and power is supplied from a power supply device to each conductive grindstone so that the polarities are opposite to each other. It is.

FIG. 1 is a conceptual diagram of an apparatus used in the grinding method of the present invention.

1 is a conductive grindstone, and the upper surface of this conductive grindstone 1 is the processing surface 1
a, and is held by a rotating shaft 2 fixed to the lower surface.

3 is a conductive grindstone, and the lower surface of this conductive grindstone 3 is the processing surface 3.
a, is held by a rotating shaft 4 fixed to the upper surface, and is installed so that its processed surface 3a faces the processed surface 1a of the conductive grindstone 1.

A grinding fluid supply nozzle 6 for supplying water-soluble grinding fluid 5 between the conductive grindstones 1 and 3 is provided near the outer peripheral surface of the conductive grindstone 3 .

Power supply brushes 7 and 8 are provided in contact with the conductive grindstone 1 and the conductive grindstone 3, and the power supply brush 7
and 8 are connected to the electrode portions 9a and 9b of the power supply unit w19, respectively.

The ta device 9 is provided with a changeover switch for connecting and varying the polarity of the electrode parts 9a and 9b, and when changing the polarity, it is not necessary in the case of alternating current, but in the case of direct current. A control portion (not shown) is provided on each side so that the polarities of the Ti pole portions 9a and 9b are reversed at regular time intervals.

Each of the conductive grindstone 1 and the conductive grindstone 3 is configured to be rotatable, movable, and pressurized by a drive means (not shown).

In the grinding process using the apparatus having the above configuration, first, the workpiece IO is held between the conductive grindstone 1 and the conductive grindstone 3 by a holding means (not shown), and the workpiece IO is ground and then the supply nozzle 6
The conductive grindstone 1 and the conductive grindstone 3 are pressurized and rotated while supplying the water-soluble grinding fluid 5 between the machined surfaces 1a and 3a. At the same time, the power supply brushes 7 and 8 are connected to the power supply device 9.
Power is supplied to the conductive grindstone 1 and the conductive grindstone 3 through the conductive grindstone 1 and the conductive grindstone 3 to perform grinding.

The grinding method of the present invention allows grinding, which has been considered difficult in the past, to be performed without providing electrodes that are closely opposed to the processing surface of a conductive grindstone.

(Example) Hereinafter, examples of the grinding method and grinding wheel of the present invention will be described in detail with reference to the drawings.

(First Embodiment) FIGS. 2(a) and 2(b) are explanatory diagrams showing the first embodiment of the grinding method of the present invention. ) is a view taken along the line AA in FIG. 2(a).

1 is a conductive grindstone, and a ring-shaped processing surface 1a is formed on the outer periphery of the upper surface of the conductive grindstone 1. The ring-shaped processing surface 1a is fixed to a lower spindle 11 rotatably attached to the lower part of a stand (not shown). The conductive whetstone 3 is a conductive whetstone, and a ring-shaped machined surface 3a is formed on the outer periphery of the top surface of the conductive whetstone 3, and is rotatably and vertically movably attached to the top of a pedestal (not shown). is fixed to the upper spindle 12,
The processed surface 3a is installed so as to face the processed surface 1a of the conductive grindstone 1.

The upper part of the conductive grindstone 1 has i! on the processing surface 1a. An outer frame 13a and an inner frame 13b are fixedly provided along the outer circumferential surface and the inner circumferential surface of the processing surface 1a to prevent the placed workpiece 10 from falling off.

A grinding fluid supply nozzle 6 is provided near the outer peripheral surface of the conductive grindstone 3 to supply a water-soluble grinding fluid 5 between the conductive grindstone 1 and the conductive grindstone 3.

The conductive whetstone 1 and the conductive whetstone 3 are connected to power supply blanks 7 and 8.
are provided so as to be in contact with each other, and the power supply blanks 7 and 8 are connected to the electrode portions 9a9b of the electric device 9, respectively.

The electric 'a device 9 is not necessary in the case of AC, but in the case of DC, a control section (not shown) is additionally provided.
The polarity of 9b is configured to be reversed at regular time intervals.

In the grinding process using the apparatus having the above configuration, a plurality of workpieces 10 and a plurality of ring-shaped spacers 14 for preventing interference between the plurality of workpieces 10 are alternately placed on the processing surface la of the conductive grindstone l. Then, the conductive grindstone 3 is lowered to a position where its processed surface 3a abuts the workpiece IO.

Next, while supplying the water-soluble grinding fluid 5 from the grinding fluid supply nozzle 6 between the machining surfaces 1a and 3a, the conductive grinding wheels 1 and 3 are controlled at appropriate pressure and speed by a driving means (not shown). Rotate under the difference. At the same time, power is supplied from the power supply device 9 to the conductive grindstone 1 and the conductive grindstone 3 via the power supply brushes 7 and 8, giving them positive and negative polarities, respectively.

When the power supply device 9 is a DC power supply, the polarity is reversed by a control section (not shown) after a certain period of time has elapsed. Furthermore, after a certain period of time has elapsed, the polarity is reversed again. This polarity reversal is performed at regular time intervals until the grinding process is completed.

According to the grinding method according to the present embodiment described above, electrolytic action occurs between the processed surfaces 1a and 3a of the conductive grindstone 1 and the conductive grindstone 3 via the water-soluble grinding fluid 5, so that another electrode A dressing action is performed on the conductive whetstone 1 and the conductive whetstone 3 without installing the conductive whetstone 1 and the conductive whetstone 3. Further, since the conductive grindstone 1 and the conductive grindstone 3 are always located at opposite positions, uniform dressing is performed, and simultaneous processing of both sides of a thin workpiece can be performed satisfactorily.

(Second Embodiment) FIGS. 3(a) and 3(b) show a second embodiment of the grinding method and grinding wheel of the present invention, FIG. 3(a) is a longitudinal sectional front view showing the main part, Figure 1) is a longitudinal sectional side view showing the state in which the workpiece 10 is held.

The grinding method shown in this embodiment is based on the shapes of the conductive grindstones 1 and 3 and the upper and lower spindles 11 in the first embodiment.
．． The difference is that the axial center position of 12 and a roller for contacting and holding the workpiece 10 are additionally provided, and the other configurations are the same. Omitted.

Reference numeral 15 denotes a conductive grindstone. The conductive grindstone 15 has a disk-like shape, has a processed surface 15a on its upper surface, and is fixed to the lower spindle 11.

Reference numeral 16 denotes a conductive whetstone. The conductive whetstone 16 has a disk-like shape, and its lower surface is formed into a processing surface 16a and is fixed to the upper spindle 12.
It is installed so as to face the processed surface 15a of.

The axis of the upper spindle 12 is offset from the axis of the lower spindle 11.

A plurality of rotatable upper rollers 17a and lower rollers 17b that contact and hold a thin plate-like workpiece 10 are arranged above and below.

In the grinding process using the apparatus having the above configuration, the thin plate-shaped work 10 is rotated by a driving means (not shown).
Machining surfaces 15a and 16a of conductive grindstones 15 and 16 rotated by upper and lower rollers 17a and 17b of ui number.
Transport between.

The water-soluble grinding fluid 5 is supplied from the grinding fluid supply nozzle 6 to the machined surface 15a.
and 16a, and also supplies power from the TLa device 9 via the power supply brushes 7 and 8 to the conductive grinding wheel 15.
and 16 machined surfaces 15a and 16a are given positive and negative polarities, respectively.

As in the first embodiment, the polarity is reversed at regular intervals until the grinding process is completed.

According to this embodiment, similar to the first embodiment, the dressing action is performed on the conductive grindstone 15 and the conductive grindstone 16 without installing another electrode.

Furthermore, simultaneous processing of both sides of a thin plate-shaped workpiece, which has been difficult in the past, can be easily and precisely performed using the same apparatus as that used for disk-shaped workpieces.

(Third Embodiment) Figures 4(a) and 4(b) show a third embodiment of the grinding method of the present invention and a third embodiment of the grinding wheel. FIG. 4(b) is a longitudinal sectional front view showing the main part of the grinding method using the grinding wheel, and FIG. 4(b) is a longitudinal sectional side view showing the state in which the workpiece IO is held.

The grinding method, the grinding fluid supply nozzle 6, the power supply brush 7.8, the power supply device 9, and the upper and lower rollers 17a, 17b in the grinding wheel shown in this embodiment are the same as those in the first and second embodiments. It is taken from the precepts, so the same number is given and the explanation is omitted.

18 is a grinding wheel, and this grinding wheel 18 is a conductive whetstone 19
The processed surface 19a of the conductive grindstone 20 and the processed surface 20a of the conductive grindstone 20 are fitted and fixed to the shaft body 22 via the wA edge 21 so as to face each other and are integrally constructed.

The grinding wheel 18 is fitted and fixed to a spindle 23 which is rotatably supported by a drive means (not shown).

The grinding wheel 18 having the above structure is fitted and fixed to the spindle 23.

The thin plate-shaped workpiece 10 is conveyed between the daily processing surfaces 19a and 520a of the rotating grinding wheel by a plurality of upper and lower rollers 17a and 17b rotated by a driving means (not shown).

The water-soluble grinding fluid 5 is supplied from the grinding fluid supply nozzle 6 to the grinding wheel 18
The grinding wheel 1
Positive and negative polarities are given to the processed surfaces 19a and 20a of No. 8, respectively.

As in the first embodiment, the polarity is reversed at regular intervals until the grinding process is completed.

According to this embodiment, since the conductive grindstones 19 and 20 are integrated into the grinding wheel 18, attachment to and removal from the spindle 23 is extremely easy and reproducible. Also,
Since the processing surfaces 19a and 20a of the grinding wheel 18 rotate coaxially, both processing surfaces of the workpiece 10 can be ground with the same quality and accuracy.

(Fourth Embodiment) Figures 5 fa) and 5 (b) show a fourth embodiment of the grinding method of the present invention, where Figure 5 (a) is a longitudinal sectional front view and Figure 5 (b) is a side view. be.

The grinding fluid supply nozzle 6 and the power supply device 9 in the grinding method shown in this embodiment have the same configuration as in the first embodiment, and therefore will be designated by the same reference numerals and a description thereof will be omitted.

The conductive grindstones 24, 25 and 26 are coaxially fixed to the conductive shaft 27, the central conductive grindstone 25 is electrically connected to the shaft 27, and the conductive grindstones 24 and 26 on both sides are connected to the shaft 27 by an insulator 28. Fixed for insulation.

Reference numeral 29 denotes an electrode, and this electrode 29 is formed in a U-shape so as to face each of the outer peripheral surfaces 24a, 25a, and 26a and the outer surfaces 24b and 26b of the conductive grindstones 2425 and 26. The electrode 29 is connected to the outer peripheral surface 25a of the conductive grindstone 25.
It is formed of a central portion 29a and side portions 29b facing each other, and the central portion 29a and side portions 29b are insulated by an insulator 30 and formed integrally.

A power supply brush 31 provided in contact with the side portion 29b of the electrode 29 and the shaft 27 is connected to the electrode 9a of the power supply device 9. In addition, the center part 29a of the electrode 29 and the conductive grindstone 2
A power supply brush 32.33 provided so as to be in contact with the outer surface 24b26b of 4.26 is connected to the electrode 9b of the power supply device 9.

That is, the same polarity is given to the conductive grindstones 24, 26 on both sides and the center part 29a of the electrode 29, and the same polarity is given to the middle conductive grindstone 25 and the side part 29b of the electrode 29. has been done.

Below the conductive grindstones 24, 25, 26, a table 34 on which a workpiece 10 is placed is provided so as to be horizontally movable.

Grinding using the apparatus configured as described above involves fixing the workpiece 10 to the table 34, setting appropriate cutting depths for the conductive grindstone 24, 25, and 26 rotated at high speed, and moving the table 34 horizontally. Move to.

At the same time, the water-soluble grinding fluid 5 is supplied from the grinding fluid supply nozzle 6 to the conductive grinding wheels 24, 25, 26, and the power supply unit 9 supplies electricity to the conductive grinding wheels 24, 25, 26. Power is supplied to i29, giving positive and negative polarities respectively.

As in the first embodiment, the polarity is reversed at regular intervals until the grinding process is completed.

According to this embodiment, it is possible to perform dressing by electrolytic action even between minute grindstones where it is difficult to install electrodes, and therefore it is possible to process a plurality of grooves with minute intervals with high accuracy.

〔Effect of the invention〕

As described above, according to the grinding method and grinding wheel of the present invention,
Since the grinding wheel itself has positive and negative electrodes, it is possible to perform dressing by electrolytic action without installing dressing electrodes, which is difficult to do in the past, such as when machining both sides of a thin workpiece at the same time. Good machining can be achieved even when

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of the grinding method and grinding wheel of the present invention, and FIG.
Figure (a) is a longitudinal cross-sectional view showing the first embodiment, Figure 2 (b) is a view taken along line AA in Figure 2 (al), Figure 3 (a) (bl indicates the second embodiment). , Fig. 3(a) is a longitudinal sectional front view;
Figure (b) is a vertical side view, Figure 4 (al) is the same
An example is shown, and FIG. 4(a) is a longitudinal sectional front view, and FIG. 4(b)
) is a vertical side view, FIGS. 5(a) and 5(b) are the fourth embodiment, FIG. 5(a) is a vertical front view, FIGS. 5-) are side views, and FIG. 6 is the conventional example. FIG. 1, 3.15, 16, 19, 20, 24, 25.26
... Conductive grindstone 2.4 ... Rotating shaft 5 ... Water-soluble grinding fluid 6 ... Grinding fluid supply nozzle 7 8.31, 32.33 ... Power supply brush 9 ... Power supply device 10 ...Workpiece 11...Lower spindle 12...Upper spindle 13a, 13b...Outer frame, inner frame 14...Spencer 17a, 17b...Upper and lower roller 1st...Grinding wheel 21, 28 .30...Insulator 22...Shaft body 23...Spindle 27...Shaft 29...Electrode 34...Table

Claims (5)

[Claims] (1) A grinding method characterized in that a plurality of conductive grindstones are installed so that their processing surfaces face each other, and processing is carried out while simultaneously applying different polarities alternately to each of the plurality of conductive grindstones. (2) The positive and negative polarities applied to the plurality of conductive grindstones,
2. The grinding method according to claim 1, wherein the grinding is performed while reversing at regular time intervals. (3) A grinding wheel characterized in that a plurality of grinding wheel segments each having electrical conductivity are integrally formed through an insulator. (4) The grinding wheel is formed by integrally forming a plurality of conductive grinding wheel segments via an insulator, and processing is performed while alternately applying different polarities to each of the plurality of grinding wheel segments at the same time. Grinding method. (5) The grinding method according to claim 4, characterized in that the processing is performed while reversing the positive and negative polarities applied to the plurality of grindstone segments of the grinding wheel at regular time intervals.