JPH05277938A - Mounting type discharge truing and its device - Google Patents

Abstract

PURPOSE:To provide a mouinting type discharge truing method of high precision within abrasive grain diameter capable of high precision on-board truing within abrasive grain diameter even against a whole shape electrically conductive grinding wheel such as a metal bond grinding wheel or an electrically conductive thin blade grinding wheel, eliminating a trouble of removing an electrically conductive grinding wheel from a grinding machine and solving a problem of deflection caused to grinding wheel installation. CONSTITUTION:Positive voltage is received from an electrically conductive grinding wheel 1 installed on a main spindle 2 and from a positive terminal 10 connected to a direct current pulse electric current or a pulse type direct current electric source 9 through a grinding stone side feeding brush 3, while negative voltage is received from an electrode 4 rotated by an electrode rotation device set on a table 7 of a grinding machine and from a negative terminal 11 connected to the electric source 9 through an electrode side feeding brush 12. By simultaneously or reciprocally carrying out discharge processing between the electrically conductive grinding wheel 1 and the electrode 4/grinding processing of the outer periphery of the grinding stone while jetting grinding processing liquid to a gap between both of them from a grinding processing liquid nozzle 16, the outer periphery of the electrically conductive grinding wheel 1 is trued in an R shape, a V shape or in a flat shape.

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 grinding truing method and apparatus for a conductive 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, an on-machine electric discharge truing / dressing method for a metal bond grindstone disclosed in JP-A-63-283861 and an unpublished application filed by the applicant is disclosed. The Japanese Patent Application 2 ─
There is an on-board discharge truing / dressing method of 331829 application. Since these methods use electric discharge machining to perform truing / dressing of the grindstone, the surface roughness of the grindstone and the initial wear of the grindstone were large. Further, in the case of shaping the R shape, since there is a discharge gap, an error occurs in the electrode shape or the grindstone starting locus and the grindstone shape, and shape correction or the like is required. There was a problem that a highly accurate grindstone shape could not be obtained.

A truing method for a thin diamond wheel was announced at the 1991 Autumn Meeting of Japan Society for Precision Engineering (Abstracts of the 1991 Autumn Meeting of Japan Society for Precision Engineering, 437 ・ 438).
page). This one uses a truing board of a metal-bonded diamond grindstone as an electrode, generates an electric discharge between the grindstone and its electrode, transfers the electrode shape to the grindstone, and further contacts the electrode, which is the truing board, with the grindstone. It was a mechanical truing method. However, since this electrode transfers the shape of the electrode to the grindstone, the electrode shape accuracy is required, and the shape accuracy is deteriorated due to electrode consumption.

[0004]

However, as described above, the conventional high-precision on-machine truing within the grain size is required for the general-type conductive grindstone such as the metal bond grindstone or the conductive thin blade grindstone. / No dressing method has been developed. Therefore, for high-precision machining that requires such a grindstone, when the shape of the grindstone has collapsed, it was not reused and was discarded. Therefore, there are problems such as being uneconomical and requiring time for setup because balancing and alignment with the work are performed each time a new grindstone is replaced. Further, when the grindstone is attached to the grinding machine, the radius of the grindstone and the runout in the lateral direction occur, which causes a problem that the sharpness of the grindstone is deteriorated or the shape of the workpiece is changed.

An object of the present invention is to enable on-machine truing with high precision within the grain size of a conductive grindstone such as a metal bond grindstone or a conductive thin grindstone, and to use the conductive grindstone. It is an object of the present invention to provide a highly accurate on-machine electric discharge truing method within an abrasive grain size that solves the problem of runout that occurs when a grindstone is attached without having to remove it from a grinding machine 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 method and apparatus as set forth in the appended claims.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an apparatus according to a first embodiment when the on-machine electric discharge grinding truing method of the present invention is applied to a conductive thin-edged grindstone of a grinding machine for cutting / grooving which is a grinding machine. Reference numeral 1 denotes a conductive thin blade grindstone having a V-shaped outer peripheral surface having a diamond abrasive grain layer formed by metal bonding on the whole grindstone, 2 a spindle for rotating the conductive thin blade grindstone 1 around it, and 3 for a center portion of the spindle 2. An example of a power feeding brush for pressing and feeding electricity to the conductive thin blade grindstone, 4 is an electrode of a metal bond diamond grindstone for simultaneously or alternately performing discharge and grinding with the outer peripheral surface of the conductive thin blade grindstone, and 5 is grinding An insulating material that insulates the electrode 4 from the board body, and 6 is an electrode rotating device for rotating the electrode 4.

Reference numeral 7 is a table of the grinder, and 8 is N (not shown).
The movement locus of the conductive thin blade grindstone 1 which is moved by the C device and trues the electric discharge machining and the grinding machining simultaneously or alternately, 9 is a DC pulse for supplying a DC pulse current between the electrode 4 of the metal bond diamond grindstone and the grindstone 1. Power source or pulsed DC power source, 10 is a positive terminal for connecting a positive voltage to the power supply brush 3, 11 is a negative terminal for supplying a negative DC pulse voltage to the electrode 4, 12 is a power supply brush for supplying power to the electrode 4, 13 Is an insulating material for insulating the power feeding brush 12 from the main body of the grinding machine, 16 is a grinding liquid nozzle, and 17 is a conductor.

In operation, the electroconductive thin blade grindstone 1 mounted on the main shaft 2 which is the rotary shaft of the grinder is rotated while being mounted on the main shaft 2 of the grinder for the grinding work, and a DC pulse current or pulse shape is applied. A positive voltage is received from the positive terminal 10 connected to the DC power source 9 via the grindstone-side power supply brush 3 and acts as a positive electrode. On the other hand, the electrode 4 installed on the table 7 of the grinding machine and rotated by the electrode rotating device receives a negative voltage from the negative terminal 11 connected to the power source 9 via the electrode side power supply brush 12, and acts as a negative electrode. Moved by an NC device (not shown),
While moving the outer periphery of the electroconductive thin blade grindstone 1 rotating on the main shaft 2 relative to the electrode 4 while ejecting the grinding fluid or the machining fluid from the grinding fluid nozzle 16 into the gap between them,
Electric discharge between the two and grinding of the outer periphery of the conductive thin blade grindstone 1 with respect to the electrode 4 are simultaneously or alternately performed to true the outer periphery of the conductive thin blade grindstone 1 into a V shape / flat shape. As a result, it is possible to avoid a decrease in the shape accuracy due to the influence of the discharge gap, and it is possible to obtain a highly accurate grindstone shape within the abrasive grain size.

FIG. 2 shows an apparatus in which the second embodiment of the on-machine electric discharge grinding truing method of the present invention is applied to the truing of a tip R-shaped grindstone of a grinding machine for profile grinding which is a grinding machine. The reference numeral 15 is a conductive shaped grindstone having a diamond abrasive grain layer formed by metal bonding on the outer circumference of the grindstone, the outer circumferential surface of the grindstone is V-shaped and the tip is R-shaped, and is rotated by the spindle 2. The electrode is the same as that of FIG. 1 except that the electrode of the metal bond diamond grindstone that performs the discharge and the grinding with the outer peripheral surface of the grindstone 15 simultaneously or alternately and 18 is the movement locus of the conductive shaped grindstone 15. Is omitted.

In operation, the grinding fluid is moved by an NC device (not shown) to move the outer periphery of the conductive thin-edged grindstone 15 rotating on the spindle 2 relative to the electrode 14 along a movement locus 18. Or, the machining fluid is a grinding fluid nozzle 1
A metal to be used for grinding by simultaneously or alternately performing electrical discharge between the two while ejecting from 6 to the gap between the two, and grinding the outer periphery of the conductive thin blade grindstone 1 with respect to the electrode 4. In the same manner, the outer shape of the bond-shaped conductive grindstone or the conductive thin blade grindstone 1 is trued to the R shape by the relative movement between the grindstone and the electrode using the NC function, and the high grain size within the abrasive grain size is similarly obtained. It is now possible to obtain a precise whetstone shape.

Contrary to FIG. 1 or 2, when the conductive grindstone is connected to the negative terminal and the positive terminal is connected to the electrode of the metal bond diamond grindstone, the conductive grindstone is processed by the thermal energy of the discharge and the grinding action. However, at that time, it is possible to truing the grindstone while consuming a small amount of the conductive electrode to which the negative terminal is connected, which makes it possible to obtain a high-precision grindstone shape, and especially for metal machining that is easy to perform electrical discharge machining. It is effective for resin bond grindstones.
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.

[0012]

As described above, according to the present invention, the electrode of the copper material used in the on-machine electric discharge truing / dressing method of the above-mentioned Japanese Patent Application No. 2-331829 is changed to a metal bond diamond grindstone, and electric discharge machining is performed. Since the grinding process is performed simultaneously or alternately to perform the truing, it is possible to avoid the deterioration of the shape accuracy due to the influence of the discharge gap, and it becomes possible to obtain a highly accurate grindstone shape within the grain size. For this reason, it is possible to perform high-precision on-machine electric discharge grinding truing of a conductive shaped grindstone such as a metal bond grindstone or a conductive thin blade grindstone, so it is not necessary to remove the grindstone from the grinding machine. There is no problem of runout that occurs, it enables reuse of a grindstone whose shape has collapsed without much effort, making the use of grinding machines cheaper,
Further, since the electric discharge and the grinding are performed simultaneously or alternately, the external force applied to the grindstone by the grinding is very small, and the on-machine electric discharge truing method and apparatus in which the deformation and the damage of the grindstone are hard to occur are provided.

[Brief description of drawings]

FIG. 1 shows a configuration of an apparatus when the first embodiment of the on-machine discharge truing method of the present invention is applied to a tip V shape or a flat upper grindstone of a grinding machine for cutting / grooving which is a grinding machine. Block diagram of main parts.

FIG. 2 is a block diagram of essential parts showing a configuration of an apparatus when a second embodiment of the on-machine electric discharge grinding truing method of the present invention is applied to the truing of a tip R-shaped grindstone of a profile grinding grinder that is a grinding machine. ..

[Explanation of symbols]

1, 15. ． Conductive whetstone 2. ． Spindle spindle 6. ． Electrode rotating device 4, 14. ． Metal bonded diamond grindstone electrode 7. ． Grinding machine table 9. ． DC pulse power supply or pulsed DC power supply 16. ． Machining fluid nozzle for ejecting grinding fluid or machining fluid

Claims (4)

[Claims] 1. A conductive grindstone mounted on a rotary shaft of a grinding machine is rotated while being mounted, and one voltage is supplied to the conductive grindstone from a DC pulse power supply or a pulsed DC power supply, and the power is supplied from the power supply. The other voltage is supplied to the electrode of the metal bond diamond grindstone installed on the table of the grinding machine, the electrode is rotated, and the DC pulse voltage is applied between the conductive grindstone and the electrode of the metal bond diamond grindstone. Is applied and the water-soluble grinding fluid is applied between the two, the electric discharge machining and the contact grinding using the diamond abrasive grains of the electrodes of the metal bond diamond grindstone are simultaneously or alternately performed, and the metal bonding of the metal bond used for the grinding is performed. The shape or thin-edged grindstone which is the conductive grindstone is formed into an R shape or V by the relative movement of the grindstone and the electrode using the NC function.
An on-machine discharge truing method characterized by truing into a flat shape or a flat shape. 2. A positive voltage is supplied from the DC pulse power supply or a pulsed DC power supply to the conductive grindstone, and a negative voltage is supplied from the power supply to the electrodes of the metal bond diamond grindstone. Item 1
On-board discharge truing method described. 3. A negative voltage is supplied from the DC pulse power supply or a pulsed DC power supply to the conductive grindstone, and a positive voltage is supplied from the power supply to the electrodes of the metal bond diamond grindstone. Item 1
On-board discharge truing method described. 4. A form or thin blade conductive grindstone mounted on a rotary shaft of a grinding machine, an electrode of a metal bond diamond grindstone installed on a table of a grinder, and a rotating electrode of the metal bond diamond grindstone. An electrode rotating device for supplying the voltage, one voltage for the conductive grindstone, and the other voltage for the electrode of the metal bond diamond grindstone, and a DC pulse power supply or a pulsed DC power supply, and the metal bond diamond When a DC pulse voltage is applied between the electrodes of the conductive grindstone and the electrodes of the metal bond diamond grindstone by rotating each of the electrodes of the grindstone and the conductive grindstone, a water-soluble grinding liquid is applied between the electrodes. The grinding fluid supply device is the same as the electric discharge machining and the contact grinding with the diamond abrasive grains of the electrodes of the metal bond diamond grindstone. Electric discharge machining to be performed sometimes or alternately
A contact grinding NC device, which is a metal-bonded conductive grindstone used for grinding, or a thin-edged grindstone, is formed into an R shape or a V shape by relative movement between the grindstone and the electrode using the NC function. An on-machine discharge truing device characterized by flat truing.