JPH05277937A - Mounting type discharge truing/dressing - Google Patents

Abstract

PURPOSE:To favourably provide a grinding wheel shape of high prescision by rotating an electrically conductive thin blade grinding wheel, supplying negative voltage to it, supplying positive voltage to an electrode and while moving the grinding wheel in parallel with the electrode, supplying grinding liquid and others between them. CONSTITUTION:By rotating an electrically conductive thin blade grinding wheel 1 installed on a main spindle 2 which is a rotation axis of a grinding machine, negative voltage is supplied from a negative terminal 11 connected to a direct current pulse electric current or a pulse type direct current power source 6 through a grinding wheel side feeding brush 4. In the meantime, to an electrode 3 set on a table 9 of the grinding machine, positive voltage is supplied from a positive terminal 10 connected to the direct current electric source 6 through an electrode side feeding brush 5. Thereafter, while jetting grinding liquid or processing liquid between the electrically conductive thin blade grinding wheel 1 and the electrode 3 from a processing liquid nozzle 7 while moving the processing liquid nozzle 7 around the outer periphery of the electrically conductive thin blade grinding wheel 1 rotating on the main spindle 2 against the electrode 3, electricity is discharged between the electrically conductive thin blade grinding wheel 1 and the electrode 3. Thereby, the outer pheriphery of the electrically conductive thin blade grinding wheel 1 is trued/dressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-machine electric discharge truing / dressing method for a conductive thin blade grindstone for a grinding machine.

[0002]

2. Description of the Related Art As a conventional on-machine electric discharge truing method for a conductive thin blade grindstone, there is an unpublished Japanese Patent Application No. 2-331829 filed by the applicant as shown in FIG. This one is
An electro-conductive thin-edged grindstone 1 used by attaching an electrode 3 for electric discharge machining on a table 9 of a grinding machine and mounting it on the grinding machine
Without removing from the machine, while rotating on the machine, positive voltage from the DC pulse power supply or pulsed DC power supply to the conductive thin blade grindstone 1, negative voltage to the electrode,
Are supplied to bring the outer peripheral portion of the conductive thin-edged grindstone 1 closer to each other, and while moving parallel to the surface of the electrode 3,
The on-machine discharge truing / dressing method of the conductive thin blade grindstone is to discharge between the electrodes and shape the outer peripheral portion of the conductive thin blade grindstone.

[0003]

Depending on the type of the binder of the conductive thin blade grindstone, such as the metal / resin bond grindstone, there are some that are easily subjected to electric discharge machining. In the above method, no matter how weak the electric discharge condition, In some cases, the surface of the electrically conductive thin blade grindstone subjected to the electric discharge was roughened, or the side surface of the grindstone was sagged by the electrolytic action, so that the shape accuracy could not be obtained. Therefore, conventionally, on-machine electrical discharge truing / dressing has not been performed on a conductive thin blade grindstone that is easily subjected to electrical discharge machining. Therefore, the conductive thin blade grindstone whose shape has been destroyed by the use of the conductive thin blade grindstone is not reused but is thrown away. This is uneconomical, and it requires balancing and alignment with the work each time a new conductive thin grindstone is exchanged, which requires setup time, and when mounting the conductive thin grindstone on a grinding machine, Since wobbling occurs in the radial direction and the side surface, the sharpness of the grindstone deteriorates,
There was a problem that the shape of the work piece changed.

An object of the present invention is to enable on-machine electric discharge truing / dressing even for a conductive thin blade grindstone which is easily subjected to electric discharge machining such as a metal / resin bond grindstone, and to remove the conductive thin blade grindstone from a grinding machine. SUMMARY OF THE INVENTION It is an object of the present invention to provide a on-machine discharge truing / dressing method that solves the problem of run-out that occurs when a grindstone is attached and can reuse a grindstone with a deformed shape.

[0005]

Therefore, the present invention has solved the above-mentioned problems of the prior art by providing an on-machine discharge truing / dressing method as claimed in the claims. That is, in the conventional method for on-machine discharge truing / dressing of a conductive thin blade grindstone, the electrode was used as a negative pole and the conductive thin blade grindstone was used as a positive pole. The problems of the prior art have been solved by providing a method of reversing the polarity of a conductive thin blade grindstone to a negative pole and positively utilizing the consumption of electrodes.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the attached FIG. FIG. 1 is a block diagram of a main part showing a configuration of an apparatus when an on-machine electric discharge truing / dressing method according to an embodiment of the present invention is applied to a grinding machine for cutting / grooving. The apparatus includes, for example, a conductive thin blade grindstone 1 having an outer peripheral surface having two back-to-back tapered surfaces having a diamond abrasive grain layer formed by metal bonding, a spindle 2 that is a rotary shaft for rotating the conductive thin blade grindstone 1, and a conductive material. A disk-shaped electrode 3 containing a conductive material such as graphite or copper to be discharged between the thin blade grindstone 1 and the outer peripheral surface thereof, and a grindstone-side power supply brush 4 which is pressed against the center portion of the spindle 2 to supply power to the thin blade grindstone 1. And, it has an electrode side power supply brush 5 for supplying power to the electrode 3.

Reference numeral 6 is a DC pulse power source for supplying a DC pulse current or a pulsed DC power source between the electrode 3 and the conductive thin blade grindstone 1. Reference numeral 7 is for jetting a grinding liquid or a working liquid between the grindstone 1 and the electrode 3. For machining fluid, 8 is an insulating material that insulates the electrode 3 from the main body of the grinding machine, 9 is a table of a grinder, 10
Is a positive terminal for supplying a positive DC pulse voltage from the power supply 6 to the electrode side power supply brush 5, 11 is a negative terminal for connecting a negative voltage from the power supply 6 to the grindstone side power supply brush 4, 12
Is a rotating device for rotating the electrode 3, and 13 is a conductor.

In operation, the conductive thin blade grindstone 1 mounted on the main shaft 2 which is the rotating shaft of the grinding machine is rotated while being mounted on the main shaft 2 of the grinding machine for the purpose of grinding work, and a DC pulse current or pulse is applied. A negative voltage is received from the negative terminal 11 connected to the DC power supply 6 in the shape of a circle via the grinding wheel side power supply brush 4. On the other hand, a positive terminal 10 connected to a power source 6 is provided for the electrode 3 installed on the table 9 of the grinding machine.
A positive voltage is received from the electrode-side power supply brush 5 to act as a positive electrode. Main shaft 2 for electrode 3
While the outer periphery of the electrically conductive thin blade grindstone 1 rotating above is moved in parallel, the grinding liquid or the machining liquid is ejected from the machining liquid nozzle 7 into the gap between the two, and when the electric discharge occurs between the two, the conductive thin blade grindstone The outer peripheral portion of No. 1 is melted by several μm by electric discharge, and the conductive coupling portion is removed to be flat. The conductive thin blade grindstone 1 can be trued / dressed by performing parallel movements several times.

In the conventional on-machine electric discharge truing / dressing method shown in FIG. 2, the conductive thin blade grindstone 1 to which the plus terminal 10 is connected is processed by the thermal energy and pressure of electric discharge.
At that time, the electrode 3 to which the negative terminal 11 is connected is also consumed in a minute amount. In the present invention, by utilizing the minute consumption of the conductive thin blade grindstone 1 to which the minus terminal 11 is connected, which corresponds to this electrode consumption, the truing / dressing of the grindstone is performed while the conductive thin blade grindstone 1 is consumed in a minute quantity. is there. This makes it possible to obtain a highly accurate grindstone shape, and is particularly effective for a metal-resin bond grindstone that is easily subjected to electric discharge machining.
Further, since the polarities are opposite, the electrolytic action works on the electrode side, and the sagging of the side surface of the grindstone does not occur. Further, the present invention can be applied not only to the flat type thin blade grindstone but also to the V type thin blade grindstone, cup grindstone, and straight grindstone.

[0010]

As described above, according to the present invention, the minute consumption of the electrically conductive thin blade grindstone to which the negative terminal is connected is utilized to perform the truing / dressing of the whetstone while the minute amount of the electrically conductive thin blade grindstone is consumed. As a result, a highly accurate grindstone shape can be obtained, which is particularly effective for metal-resin bond grindstones that are easy to perform electrical discharge machining, and the polarity is reversed, so the electrolytic action works on the electrode side and sagging on the side surface of the grindstone It stopped happening. In addition to the flat thin blade, it can also be applied to V thin blades, cups, and straight grinding stones, and can be used for on-machine discharge truing / dressing even for thin blades that are susceptible to electrical discharge machining, such as metal / resin bond wheels. Made possible. Therefore, it is not necessary to remove the grindstone from the grinding machine, the problem of run-out that occurs when the grindstone is attached is solved, and the grindstone with a deformed shape can be reused. Further, since the electric discharge truing is performed without applying an external force to the grindstone, the grindstone can be prevented from being deformed or damaged. Furthermore, the width of the V-shaped grinding
It is possible to truing / dressing a 0.3mm metal resin bond thin blade grindstone, and its tip R has a sharp edge of 20 μm or less.

[Brief description of drawings]

FIG. 1 is a block diagram of essential parts showing a configuration of an apparatus when an on-machine discharge truing / dressing method according to an embodiment of the present invention is applied to a grinding machine for cutting / grooving.

FIG. 2 is a principal block diagram showing a configuration of an apparatus when a conventional on-machine electric discharge truing / dressing method is applied to a grinding machine for cutting / grooving.

[Explanation of symbols]

1. ． Conductive thin blade whetstone 2. ． Spindle that is a rotating shaft 3. ． Disc-shaped electrode 6. ． DC pulse power supply that supplies pulsed DC power supply 7. ． Processing liquid nozzle for ejecting grinding liquid or processing liquid 9. ． Grinding machine table

Claims (1)

[Claims] 1. A negative voltage is supplied from a DC pulse power source or a pulsed DC power source to the electroconductive thin blade grindstone by rotating the electroconductive thin blade grindstone mounted on the rotary shaft of a grinding machine with the DC voltage applied. A positive voltage is supplied from the power source to the electrode installed on the table of the grinding machine from a pulse power source or a pulsed DC power source, and the outer periphery of the rotating conductive thin-edged grindstone is parallel to the surface of the electrode. An on-machine electric discharge truing / dressing method characterized by truing / dressing the outer periphery of the electroconductive thin blade grindstone by causing electric discharge while supplying a grinding liquid or a working liquid between the two while moving the electric discharge.