JP2886203B2 - Electrolytic grinding method and apparatus - Google Patents

Description

Description: TECHNICAL 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 performing grinding using electrolytically dressing a tool.

[Conventional technology]

Conventionally, a grinding method using a surface grinder shown in FIG. 5 has been proposed as a grinding process performed while simultaneously using dressing of a tool by an electrolytic action. As an example of such general knowledge of grinding, there is a collection of academic papers of the 1989 Spring Society of Precision Engineering (p. 373).

In FIG. 5, reference numeral 101 denotes a conductive grinding tool, which is rotatably held. The rotary table 102 is disposed to face the conductive grinding tool 101 and is rotatable. An electrode 113 is provided between the conductive grinding tool 101 and the rotary table
It is installed so as to be close to and facing the 1 processing surface 101a,
The electrode 113 is connected to the negative electrode of the power supply device 111. The power supply brush 112 is in contact with the conductive grinding tool 101,
The positive electrode from 111 can be supplied to the conductive grinding 101. Also, the electrode 113 and the conductive grinding tool 101
A pipe 103 for supplying a water-soluble grinding fluid 104 is provided on the processing surface 101a.

In processing, the work 105 is placed between the conductive grinding tool 101 and the rotary table 102, and while the water-soluble grinding fluid 104 is constantly supplied from the grinding fluid supply pipe 103, the power is supplied to the conductive grinding tool 101 and the electrode 113. While the power is supplied by the device 111, it is performed in the same manner as the known grinding processing in the surface grinder.

According to the above-described conventional example, an electrolytic action is generated between the conductive grinding tool 101 and the electrode 113 which are provided to face each other via the water-soluble grinding fluid 104, and the bonding material (the aforementioned Bonds that bond abrasive grains that make up a grinding tool)
Elutes little by little and performs dressing action,
Processing without clogging can always be performed.

[Problems to be solved by the invention]

However, in the prior art, a slight clearance l (preferably, about 0.1 to 0.2 mm) is maintained between the electrode 113 and the processing surface 101a of the conductive grinding tool 101 which is brought close to and opposed to the electrode. A voltage or current (preferably, a voltage of about several tens of volts, a current of about several A) must be maintained. For this reason, every time the conductive grinding tool 101 is changed, the clearance l must be finely adjusted by manual setup, which makes the setup extremely difficult.

Therefore, the present invention has been developed in view of the drawbacks in the prior art, the conductive grinding tool while measuring the voltage or current so that the desired applied voltage or current
It is an object of the present invention to provide a method and an apparatus for performing a grinding process by causing an electrode to approach and approach a processing surface 101a of a substrate 101 while appropriately controlling the electrode.

[Means and actions for solving the problem]

The present invention provides a rotatable conductive grinding tool for processing a workpiece as an anode, an electrode facing a part of a processing surface of the conductive grinding tool as a cathode, and a processing surface of the conductive grinding tool. In an electrolytic grinding method for processing a workpiece on a processing surface of a conductive grinding tool that is not opposed to the electrode while interposing a weakly conductive coolant between a part and the electrode,
Measure the voltage or current applied to the conductive grinding tool and the electrode, while controlling the electrode position with respect to the processing surface of the conductive grinding tool so that the value is a desired value, while maintaining a constant gap Perform processing.

In addition, a rotatable conductive grinding tool for processing a workpiece and a grinding portion including an electrode opposed to a part of a processing surface of the conductive grinding tool, and the conductive grinding tool as an anode and the electrode as a cathode. A power supply unit to be applied, a driving unit that movably holds the electrode, a voltage or current applied to the conductive grinding tool and the electrode is measured, and the driving unit is controlled by a numerical value to control the driving unit. A control unit configured to make a gap between the conductive grinding tool and a processing surface constant; and a supply unit configured to supply a weakly conductive coolant between a part of the processing surface of the conductive grinding tool and the electrode. Things.

FIG. 1 is a conceptual diagram of an apparatus used for the electrolytic grinding method according to the present invention.

Reference numeral 1 denotes a conductive grinding tool. The conductive grinding tool 1 is a sintered alloy obtained by specially mixing and heat-treating abrasive grains of diamond powder and metal powders of Cu, Sn, Fe, etc., and held rotatably. . The holding plate 10 is disposed to face the conductive grinding tool 1 and holds the work 5 rotatably. In the vicinity of the processing surface 1a of the conductive grinding tool 1, a pipe 3 for supplying a weakly conductive coolant is provided. The conductive tool 1 has a power supply brush 12.
The power supply brush 12 is a DC power supply.
Connected to 11 anodes.

The electrode 13 is supported by the electrode support 14 and the electrode support 14
Is fixed to the table 15. Table 15 is a table
The electrode 13 is slidably provided on the table 16, and the electrodes 13 are configured to be movable in three-dimensional directions by servo motors 17, 18, and 19 provided on the table 15 and the table 16, respectively.
The electrode 13 is connected to the cathode of the DC power supply 11. The power supply 11 is connected to a control unit 20, and the control unit 20 is connected to the servo motors 17, 18, and 19.

Using the device having the above-described configuration, the power supply 11 applies the power to the power supply brush 12 and the electrode 13, and the servo motors 17, 18, and 19 determine the position of the electrode 13 while measuring the voltage and current by the control unit 20. The position is adjusted while being controlled by the control unit 20. Then, from the point in time when a desired voltage or a desired current is obtained by adjusting the position of the electrode 13, the processing surface 1 a of the conductive grinding tool 1 is dressed by electrolysis via the weakly conductive coolant 4 to be supplied.

〔Example〕

Hereinafter, embodiments of the apparatus used in the electrolytic grinding method according to the present invention will be described in detail with reference to the drawings.

First Embodiment FIGS. 2a and 2b are schematic structural views showing a first embodiment of an apparatus used for the electrolytic grinding method according to the present invention.

The electrolytic grinding apparatus shown in this embodiment is different from the grinding apparatus shown in FIG. 1 in that a conductive grinding tool 21 and a holding plate 23 are supported by a kansashi 22 instead of the conductive grinding tool 1 and the holding plate 10. Differently, the other components are the same, and the other components are denoted by the same reference numerals and description thereof is omitted.

Reference numeral 21 denotes a conductive grinding tool. The conductive grinding tool 21 is provided with a pellet-shaped processing surface 21a, and is configured to be rotatable. A holding plate 23 disposed opposite to the conductive grinding tool 21 is supported by a wrench 22. The kansashi 22 is configured to press and swing the subordinate rotating holding plate 23 by a mechanism not shown. Hereinafter, the configuration is the same as that of FIG. 1, and the description thereof is omitted.

Using the apparatus having the above-described configuration, the conductive grinding tool 21 is rotated by a driving device (not shown), and the work 5 that is driven and rotated by the wrench 22 is swung while being appropriately pressurized. At the same time, the servo motors 17, 18, and 19 are driven while applying the anode to the conductive tool 21 via the power supply brush 12 and the cathode to the electrode 13 by the power supply 11, and bring the electrode 13 close to the processing surface 21a. The current starts to flow due to this proximity. Next, the current and voltage that have started to flow are measured by the control unit 20, and the servo motors 17, 18, and 19 are driven until the desired current or voltage is obtained, and processing is performed while controlling the position of the electrode 13 by the control unit 20. . At this time, when the current or the voltage exceeds the desired current or the desired voltage, the clearance l between the processing surface 21a and the electrode 13 is increased, and when the current or the voltage does not reach, the clearance l is reduced and the processing is advanced while adjusting as needed. Then, by supplying the weakly electric coolant 4 between the processing surface 21a and the electrode 13, the processing surface 21a is supplied.
a is dressed by electrolysis.

According to the present embodiment, an appropriate electrolytic dressing can be obtained by adjusting the position of the electrode 13 as needed while measuring the current or the voltage.

(Second Embodiment) FIGS. 3a, 3b, and 3c show a second embodiment of the apparatus used in the electrolytic grinding method according to the present invention, and FIG.
FIGS. B and c are views taken along line AA of FIG. 3a.

The conductive grinding tool 1, the pipe 3, the power supply 11, the power supply brush 12, and the control unit 20 in this embodiment have the same configurations as those in FIG.

Reference numeral 24 denotes an electrode, which is constituted by radially provided electrode portions 24a, 24b, 24c, 24d, 25e, and 24f. The electrode 24 is rotatably held by an encoder 25.
The encoder 25 is held by a servomotor 26 and is movable vertically, and the servomotor 26 is fixed to a table 28. A servo motor 27 is connected to the table 28, and the servo motor 27 is provided so as to be movable on the base 29 in the horizontal direction.

Using the apparatus having the above configuration, processing is performed in the same manner as in the first embodiment. At this time, the electrode 24 is rotated by the encoder 25 as shown in FIG. 3B, and machining is performed using the electrode portion 24f corresponding to the diameter of the conductive grinding tool 1. In the case of the conductive grinding tool 30 having a large diameter, the electrode 24 is rotated by the encoder 25 as shown in FIG.
The processing is performed using the electrode portion 24c corresponding to the diameter of.

According to this embodiment, the electrode portions corresponding to the diameters of various kinds of conductive grinding tools can be easily selected, and the same effects as in the first embodiment can be obtained.

(Third Embodiment) Figs. 4a and 4b show a third embodiment of the apparatus used in the electrolytic grinding method according to the present invention, where Fig. 4a is a schematic configuration diagram, and Fig. 4b is that of Fig. 4a. It is a BB line arrow line view.

The conductive grinding tool 1, the pipe 3, the power source 11, the power supply brush 12, the electrode support part 14, and the control part 20 in this embodiment have the same configuration as in FIG. Omitted.

Reference numeral 33 denotes an electrode, and the electrode 33 is provided with electrode portions 33a, 33b, and 33c.

The electrode 33 is supported by the electrode support 14 and the electrode support 14
Is fixed to the table 28.

Servo motor fixed to base 29 on table 28
The servo motor 27 is connected to the base 29 so as to be movable in the horizontal direction. The base 29 is vertically movably held by a servomotor 31, and the servomotor 31 is fixed to the base 32.

Using the apparatus having the above configuration, processing is performed in the same manner as in the first embodiment. At this time, the electrode 33 is moved by the servo motor 27 as shown in FIG. 4B, and the electrode 33 is processed using the electrode portion 33b corresponding to the diameter of the conductive grinding tool 1.

According to this embodiment, the same effects as in the second embodiment can be obtained.

〔The invention's effect〕

Since the electrodes are moved by automatic control and can be set to a desired current or a desired voltage, appropriate electrolytic dressing can be constantly performed, processing conditions can be stabilized, and stable electrolytic grinding can be performed.

[Brief description of the drawings]

FIGS. 1a and 1b are conceptual diagrams of an apparatus used in the electrode grinding method according to the present invention, FIGS. 2a and 2b are schematic diagrams showing the first embodiment, respectively, and FIGS. 3a, 3b and 3c are respectively FIG. 3A is a schematic diagram showing the second embodiment, and FIGS. 3B and 3C are views taken along line AA of FIG. 3A, respectively.
4a and 4b show the third embodiment, respectively.
Fig. A is a schematic configuration diagram, Fig. 4b is a view taken along line BB of Fig. 4a, and Fig. 5 is a schematic configuration diagram showing a conventional example. 1,21 ... conductive grinding tool 1a, 21a ... work surface 3 ... pipe 4 ... weakly conductive coolant 5 ... workpiece 10,23 ... holding plate 11 ... power supply 12 ... power supply brush 13,24, 33 Electrode 14 Electrode support 15, 16, 28 Table 17, 18, 19, 26, 27, 31 Servo motor 20 Control

──────────────────────────────────────────────────続 き Continuing on the front page (72) Keiji Uchiyama, inventor Keiji Uchiyama 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP 50-74293 (JP, A) 50-156523 (JP, U) JP 46-29117 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B24B 13/01 B23H 5/06 B23H 3/04

Claims (2)

(57) [Claims] 1. A rotatable conductive grinding tool for processing a workpiece is used as an anode, an electrode facing a part of a processing surface of the conductive grinding tool is applied as a cathode, and the conductive grinding tool is processed. An electrolytic grinding method for processing a workpiece on a processing surface of a conductive grinding tool that is not opposed to the electrode while interposing a weakly conductive coolant between a part of the surface and the electrode, wherein the conductive grinding tool and the electrode Measuring the voltage or current applied to the electrode, controlling the electrode position with respect to the processing surface of the conductive grinding tool so that the value becomes a desired value, and performing machining while maintaining a constant gap. Grinding method. 2. A grinding part comprising a rotatable conductive grinding tool for processing a workpiece, and an electrode facing a part of a processing surface of the conductive grinding tool, and the electrode having the conductive grinding tool as an anode. A power supply unit that applies the negative electrode as a cathode, a driving unit that movably holds the electrode, a voltage or current applied to the conductive grinding tool and the electrode, and the driving unit is controlled by a numerical value to control the driving unit. A control unit that makes the gap between the electrode and the processing surface of the conductive grinding tool constant, and a supply unit that supplies a weakly conductive coolant between a part of the processing surface of the conductive grinding tool and the electrode. An electrolytic grinding apparatus comprising: